The rheological properties of nanocellulose aqueous suspensions play a critical role in the development of nanocellulose-based bulk materials.High-crystalline,high-aspect ratio,and slender nanofibrillated cellulose(NF...The rheological properties of nanocellulose aqueous suspensions play a critical role in the development of nanocellulose-based bulk materials.High-crystalline,high-aspect ratio,and slender nanofibrillated cellulose(NFC)were extracted from four biomass resources.The cellulose nanofibrils and nanofibril bundles formed inter-connected networks in the NFC aqueous suspensions.The storage moduli of the suspensions with different concentrations were higher than their corresponding loss moduli.As the concentration increased,the storage and loss modulus of NFC dispersion increased.When the shear rate increased to a certain value,there were differences in the changing trend of the rheological behavior of NFC aqueous suspensions derived from different biomass resources and the suspensions with different solid concentrations.NFC dispersion’s storage and loss modulus increased when the temperature rose to nearly 80℃.We hope this study can deepen the understanding of the rheological properties of NFC colloids derived from different biomass resources.展开更多
One-time application of mixed fertilizer formed by the compounding of two controlled-release nitrogen fertilizers(CRUs)with targeted N supply during the periods from transplantation(TS)to panicle initiation(PI)and fro...One-time application of mixed fertilizer formed by the compounding of two controlled-release nitrogen fertilizers(CRUs)with targeted N supply during the periods from transplantation(TS)to panicle initiation(PI)and from PI to heading(HS)is expected to synchronize the double-peak N demand of rice.However,its effects on the yield and N use efficiency(NUE)of labor-intensive double-cropping rice were unknown.Two targeted CRU(CRU_(A)and CRU_(B))were compounded in five ratios(CRU_(A):CRU_(B)=10:0,7:3,5:5,3:7,and 0:10)to form five mixed fertilizers(BBFs):BBF1-5.A field experiment was performed to investigate the characteristics of N supply in early and late seasons under different BBFs and their effects on N uptake,yield,and ammonia volatilization(AV)loss from paddy fields of double-cropping rice.Conventional high-yield fertilization(CK,three split applications of urea)and zero-N treatments were established as controls.The N supply dropped significantly with the increased compound ratio of CRU_(B)during the period from TS to PI,but increased during the period from PI to HS.With the exception of the period from TS to PI in the late rice season,the N uptake of early and late rice maintained close synchronicity with the N supply of BBFs during the double-peak periods.Excessive N supply(BBF1 and BBF2)in the late rice season during the period from TS to PI increased N loss by AV.The effect of BBF on grain yield increase varied widely between seasons,irrespective of year.Among the BBFs,the BBF2 treatment of early rice not only stabilized the spikelets per panicle but also ensured a high number of effective panicles by promoting N uptake during the period from TS to PI and a high grain-filling percentage by appropriately reducing the N supply at the later PI stage,resulting in the highest rice yield.While stabilizing the effective panicle number,the BBF4 treatment of late rice increased the number of spikelets per panicle by promoting N uptake during the period from PI to HS,resulting in the highest rice yield.The two-year average yield and apparent N recovery efficiency of the BBF2 treatment during the early rice season were 9.6 t ha 1 and 45.3%,while those of late rice in BBF4 were 9.6 t ha 1 and 43.0%,respectively.The yield and NUE indexes of BBF2 in early rice and BBF4 in late rice showed no significant difference from those of CK.The AVs of BBF2 during the early rice season and of BBF4 during the late rice season were 50.0%and 76.8%lower,respectively,than those of CK.BBF2 and BBF4 could effectively replace conventional urea split fertilization in early and late rice seasons,ensuring rice yield and NUE and reducing AV loss in paddy fields.展开更多
Silica aerogel with different hydrophilicities were prepared from tetramethoxysilane,Methymethoxysilane,tetramethoxysilane-propyltrimethoxysilane,or tetramethoxysilane-phenyltrimethoxysilane mixtures via supercritical...Silica aerogel with different hydrophilicities were prepared from tetramethoxysilane,Methymethoxysilane,tetramethoxysilane-propyltrimethoxysilane,or tetramethoxysilane-phenyltrimethoxysilane mixtures via supercritical drying process(labelled as TMOS-AG Me-TMOS-AG,Pr-TMOS-AG,or Ph-TMOS-AG,respectively).Three fragrances,including geraniol,ethyl vanillin,and menthol,were loaded to TMOS-AG.The thermal analysis confirmed all loading fragrances are stable until over 200℃.And among all fragrances,geraniol presented the maximum loading contents(L_(m)).Concentration dependences indicated the geraniol was mono layer absorbed.Py-GC/MS of geraniol in TMOS-AG under both N_(2)and mimic air atmosphere(90%N_(2)and 10%O_(2))confirmed that loaded geraniol could be thermally controlled-released beginning at 200℃.As N_(2)absorption confirmed,even absorption/desorption equilibrium constant(k)was determined mainly by hydrophilicity of silica aerogels,and the maximum loading contents(L_(m))were influenced more by the pore size.Due to mono layered absorption,bigger pores usually give less specific areas and less absorbing sites for geraniol,and then present lower L_(m).展开更多
A mixture of controlled-release urea and normal urea(CRUNU)is an efficient nitrogen(N)fertilizer type,but little is known about its effects on stem lodging resistance,grain yield,and yield stability of wheat.In this s...A mixture of controlled-release urea and normal urea(CRUNU)is an efficient nitrogen(N)fertilizer type,but little is known about its effects on stem lodging resistance,grain yield,and yield stability of wheat.In this study,a 4-year field experiment(from 2017 to 2021)was conducted to analyze the effects of N fertilizer types(CRUNU and normal urea(NU))and application rates(low level(L),135 kg ha^(–1);medium level(M),180 kg ha^(–1);high level(H),225 kg ha^(–1))on population lodging resistance,basal internode strength,lignin content and synthetase activity,stem lodging resistance,grain yield,and yield stability of wheat.Our results showed that the two N fertilizer types had the highest lodging rate under high N application rates,and the M-CRUNU treatment showed the lowest lodging rate.Compared with NU,CRUNU improved the wheat population lodging resistance under the three N application rates,mainly related to improving wheat population characteristics and breaking the strength of the second basal internode.Correlation analysis showed that the breaking strength of the second basal internode was related to the physical characteristics,chemical components,and micro-structure of the internode.Compared with NU,CRUNU significantly increased wheat grain yield by 4.47,14.62,and 3.12%under low,medium,and high N application rates,respectively.In addition,CRUNU showed no significant difference in grain yield under medium and high N application rates,but it presented the highest yield stability under the medium N application rate.In summary,CRUNU,combined with the medium N application rate,is an efficient agronomic management strategy for wheat production.展开更多
Controlled-release urea(CRU)is widely reported to supply crop nitrogen(N)demand with one basal application,thus effectively replacing split applications of urea without diminishing grain yield and N use efficiency(NUE...Controlled-release urea(CRU)is widely reported to supply crop nitrogen(N)demand with one basal application,thus effectively replacing split applications of urea without diminishing grain yield and N use efficiency(NUE).However,its use for replacement for high-yield split applications of urea(CK)for rice is untested.In addition,the degree to which greenhouse gas(GHG)emissions in rice systems are affected when CRU is substituted for CK remains unclear.During 2017 and 2018,we sampled plant growth and gas emissions in a rice paddy field treated with three CRU types(sulfur-coated urea[SCU],polymer-coated urea[PCU],and bulk blended CRU[BBU])applied via two methods(surface broadcasting on the soil and subsurface banding at 5 cm depth),with CK as a control.The three CRUs led to different soil NH_(4)^(+)-N dynamics,and the N supply pattern under BBU was more beneficial for rice seedling establishment than under SCU and PCU,resulting in grain yield and NUE comparable to those under CK.CRU type showed no significant effect on either CH_(4) emissions or N_(2)O emissions,and broadcast CRUs exhibited significantly higher total GHG emissions than CK.However,banded CRUs significantly reduced the total GHG emissions in comparison with broadcast CRUs,by 9.2%averaged across the two years.Reduced CH_(4) emissions,particularly during the period prior to the middle drainage,contributed largely to the GHG difference.With comparably high grain yield and low total GHG emissions,banded BBU showed a low yield-scaled GHG(GHG emissions divided by grain yield)comparable to that under CK in both years.Overall,our study suggested that N management synchronized with rice demand and contributing to a high NUE tended to minimize yield-scaled GHG.Broadcast CRU can hardly substitute for CK in terms of either grain yield or GHG emissions,but banded BBU is a promising N management strategy for sustaining rice production while minimizing environmental impacts.展开更多
X-ray photon correlation spectroscopy(XPCS)has emerged as a powerful tool for probing the nanoscale dynamics of soft condensed matter and strongly correlated materials owing to its high spatial resolution and penetrat...X-ray photon correlation spectroscopy(XPCS)has emerged as a powerful tool for probing the nanoscale dynamics of soft condensed matter and strongly correlated materials owing to its high spatial resolution and penetration capabilities.This technique requires high brilliance and beam coherence,which are not directly available at modern synchrotron beamlines in China.To facilitate future XPCS experiments,we modified the optical setup of the newly commissioned BL10U1 USAXS beamline at the Shanghai Synchrotron Radiation Facility(SSRF).Subsequently,we performed XPCS measurements on silica suspensions in glycerol,which were opaque owing to their high concentrations.Images were collected using a high frame rate area detector.A comprehensive analysis was performed,yielding correlation functions and several key dynamic parameters.All the results were consistent with the theory of Brownian motion and demonstrated the feasibility of XPCS at SSRF.Finally,by carefully optimizing the setup and analyzing the algorithms,we achieved a time resolution of 2 ms,which enabled the characterization of millisecond dynamics in opaque systems.展开更多
This paper addresses the impact of vertical vibration negative effects,unbalanced radial forces generated by the static eccentricity of the hub motor,and road excitation on the suspension performance of Hub Motor Driv...This paper addresses the impact of vertical vibration negative effects,unbalanced radial forces generated by the static eccentricity of the hub motor,and road excitation on the suspension performance of Hub Motor Driven Vehicle(HMDV).A dynamic inertial suspension based on Active Disturbance Rejection Control(ADRC)is proposed,combining the vertical dynamic characteristics of dynamic inertial suspension with the features of ADRC,which distinguishes between internal and external disturbances and arranges the transition process.Firstly,a simulation model of the static eccentricity of the hub motor is established to simulate the unbalanced radial electromagnetic force generated under static eccentricity.A quarter-vehicle model of an HMDV with a controllable dynamic inertial suspension is then constructed.Subsequently,the passive suspension model is studied under different grades of road excitation,and the impact mechanism of suspension performance at speeds of 0–20 m/s is analyzed.Next,the three main components within the ADRC controller are designed for the second-order controlled system,and optimization algorithms are used to optimize its internal parameters.Finally,the performance of the traditional passive suspension,the PID-based controllable dynamic inertial suspension,and the ADRC-based controllable dynamic inertial suspension are analyzed under different road inputs.Simulation results show that,under sinusoidal road input,the ADRC-based controllable dynamic inertial suspension exhibits a 52.3%reduction in the low-frequency resonance peak in the vehicle body acceleration gain diagram compared to the traditional passive suspension,with significant performance optimization in the high-frequency range.Under random road input,the ADRC-based controllable dynamic inertial suspension achieves a 29.53%reduction in the root mean square value of vehicle body acceleration and a 14.87%reduction in dynamic tire load.This indicates that the designed controllable dynamic inertial suspension possesses excellent vibration isolation performance.展开更多
Active suspension systems(ASSs)have been proposed and developed for a few decades,and have now once again become a thriving topic in both academia and industry,due to the high demand for driving comfort and safety and...Active suspension systems(ASSs)have been proposed and developed for a few decades,and have now once again become a thriving topic in both academia and industry,due to the high demand for driving comfort and safety and the compatibility of ASSs with vehicle electrification and autonomy.Existing review papers on ASSs mainly cover dynamics modeling and robust control;however,the gap between academic research outcomes and industrial application requirements has not yet been bridged,hindering most ASS research knowledge from being transferred to vehicle companies.This paper comprehensively reviews advances in ASSs for road vehicles,with a focus on hardware structures and control strategies.In particular,state-of-the-art ASSs that have been recently adopted in production cars are discussed in detail,including the representative solutions of Mercedes active body control(ABC)and Audi predictive active suspension;novel concepts that could become alternative candidates are also introduced,including series active variable geometry suspension,and the active wheel-alignment system.ASSs with compact structure,small mass increment,low power consumption,high-frequency response,acceptable economic costs,and high reliability are more likely to be adopted by car manufacturers.In terms of control strategies,the development of future ASSs aims not only to stabilize the chassis attitude and attenuate the chassis vibration,but also to enable ASSs to cooperate with other modules(e.g.,steering and braking)and sensors(e.g.,cameras)within a car,and even with high-level decision-making(e.g.,reference driving speed)in the overall transportation system-strategies that will be compatible with the rapidly developing electric and autonomous vehicles.展开更多
Tissue culture techniques were used to produce large amounts of bioactive compounds with medicinal potential, overcoming space and time constraints for cancer prevention. Rice callus suspension cultures(RCSC) and seed...Tissue culture techniques were used to produce large amounts of bioactive compounds with medicinal potential, overcoming space and time constraints for cancer prevention. Rice callus suspension cultures(RCSC) and seed extracts prepared from aromatic rice varieties were used to evaluate the cytotoxic impact on human colon and lung cancer cell lines, as well as a normal control cell line, using Taxol as a positive control. RCSC and seed extracts from two Indian aromatic rice varieties were applied at different concentrations to treat the cancer cell lines and normal lung fibroblasts over varying time intervals. Apoptosis was assessed in 1:5 dilutions of the A549 and HT-29 cell lines treated with RCSC for 72 h, using propidium iodide staining and flow cytometry. RCSC showed a more potent cytotoxic effect than seed extracts with minimal effect on the normal cell line, in contrast to Taxol. Confocal microscopy and flow cytometry further confirmed the apoptotic effect of RCSC. Gas chromatography-mass spectrometry-based metabolic profiling identified metabolites involved in cytotoxicity and highlighted altered pathways. RCSC is proposed as an alternative source for the development of novel anticancer drugs with reduced side effects.展开更多
AIM:To investigate the symmetry of upper eyelid in patients with unilateral mild and moderate blepharoptosis who underwent unilateral minimally invasive combined fascia sheath(CFS)suspension.METHODS:A retrospective st...AIM:To investigate the symmetry of upper eyelid in patients with unilateral mild and moderate blepharoptosis who underwent unilateral minimally invasive combined fascia sheath(CFS)suspension.METHODS:A retrospective study of patients who underwent unilateral minimally invasive CFS suspension surgery between January 2018 and December 2021.Inclusion criteria included unilateral mild and moderate ptosis,good levator muscle function(>9 mm)and follow-up of at least 6mo.Pre-and post-operative symmetry was graded subjectively for marginal reflex distance 1(MRD1),tarsal platform show(TPS)and eyebrow fat span(BFS).A t-test was used to evaluate MRD1,TPS and BFS asymmetry by calculating delta values.The Bézier curve tool of the Image J software was used to extract the upper eyelid contours,where the symmetry was measured by the percentage of overlapping curvatures(POC).RESULTS:Totally 105 patients(105 eyelids)were included(mild group,n=84;moderate group,n=21).Postoperatively,all patients increased MRD1 and decreased TPS in the ptotic eye while maintaining unchanged BFS.The asymmetric delta value for MRD1 was measured to be 1.48±0.86 preoperatively,and it decreased to 0.58±0.67 postoperatively in all cases(P=0.0004).In patients with mild ptosis,the asymmetry value of TPS fell significantly from 1.15±0.62 to 0.68±0.38(P=0.0187).The symmetry of the upper eyelid contour increased in all subgroups of patients,with a POC of 59.39%±13.45%preoperatively and POC of 78.29%±13.80%postoperatively.CONCLUSION:Minimally invasive CFS suspension is proved to be an effective means of improving the symmetry of unilateral ptosis in terms of MRD1(all subgroups),POC(all subgroups)and TPS(only mild group),whereas BFS is unaffected.展开更多
This paper presents an integrated control scheme for enhancing the ride comfort and handling performance of a four-wheel-independent-drive electric vehicle through the coordination of active suspension system(ASS)and ...This paper presents an integrated control scheme for enhancing the ride comfort and handling performance of a four-wheel-independent-drive electric vehicle through the coordination of active suspension system(ASS)and anti-lock braking system(ABS).First,a longitudinal-vertical coupled vehicle dynamics model is established by integrating a road input model.Then the coupling mechanisms between longitudinal and vertical vehicle dynamics are analyzed.An ASS-ABS integrated control system is proposed,utilizing an H∞controller for ASS to optimize load transfer effect and a neural network sliding mode control for ABS implementation.Finally,the effectiveness of the proposed control scheme is evaluated through comprehensive tests conducted on a hardware-in-loop(HIL)test platform.The HIL test results demonstrate that the proposed control scheme can significantly improve the braking performance and ride comfort compared to conventional ABS control methods.展开更多
This paper addresses the sampled-data multi-objective active suspension control problem for an in-wheel motor driven electric vehicle subject to stochastic sampling periods and asynchronous premise variables.The focus...This paper addresses the sampled-data multi-objective active suspension control problem for an in-wheel motor driven electric vehicle subject to stochastic sampling periods and asynchronous premise variables.The focus is placed on the scenario that the dynamical state of the half-vehicle active suspension system is transmitted over an in-vehicle controller area network that only permits the transmission of sampled data packets.For this purpose,a stochastic sampling mechanism is developed such that the sampling periods can randomly switch among different values with certain mathematical probabilities.Then,an asynchronous fuzzy sampled-data controller,featuring distinct premise variables from the active suspension system,is constructed to eliminate the stringent requirement that the sampled-data controller has to share the same grades of membership.Furthermore,novel criteria for both stability analysis and controller design are derived in order to guarantee that the resultant closed-loop active suspension system is stochastically stable with simultaneous𝐻2 and𝐻∞performance requirements.Finally,the effectiveness of the proposed stochastic sampled-data multi-objective control method is verified via several numerical cases studies in both time domain and frequency domain under various road disturbance profiles.展开更多
Steel truss suspension bridges are prone to developing defects after prolonged use.These defects may include corrosion of the main cable or the steel truss.To ensure the normal and safe functioning of the suspension b...Steel truss suspension bridges are prone to developing defects after prolonged use.These defects may include corrosion of the main cable or the steel truss.To ensure the normal and safe functioning of the suspension bridge,it is necessary to inspect for defects promptly,understand the cause of the defect,and locate it through the use of inspection technology.By promptly addressing defects,the suspension bridge’s safety can be ensured.The author has analyzed the common defects and causes of steel truss suspension bridges and proposed specific inspection technologies.This research is intended to aid in the timely discovery of steel truss suspension bridge defects.展开更多
Objective:To evaluate the clinical advantages of laparoscopic transverse abdominal wall suspension in treating pelvic organ prolapse.Methods:Sixty patients diagnosed with moderate to severe pelvic organ prolapse and u...Objective:To evaluate the clinical advantages of laparoscopic transverse abdominal wall suspension in treating pelvic organ prolapse.Methods:Sixty patients diagnosed with moderate to severe pelvic organ prolapse and underwent surgical treatment in our hospital between January 2022 and December 2023 were selected.According to different surgical methods,they were divided into an observation group(given laparoscopic transverse abdominal wall suspension)and a control group(given transvaginal mesh implantation),with 30 subjects/group.The data on perioperative-related indicators,quality of life scores,postoperative recurrence,and complications of the two groups of patients were collected.Results:The postoperative hospitalization days and intraoperative bleeding volume of the observation group were significantly lower than those of the control group,but had longer operation time than that of the control group(P<0.05).The differences between the two groups were statistically significant 6 months after surgery,and the Pelvic Floor Disease Quality of Life Impact Questionnaire(PFIQ-7)score of the observation group was significantly higher than the control group(P<0.05).Both groups of patients completed 12 months of follow-up without any postoperative recurrence.The number of complications in the observation group was slightly lower than that of the control group(P>0.05).Conclusion:Laparoscopic transverse abdominal wall suspension was more effective in treating pelvic organ prolapse and is an ideal surgical procedure.展开更多
A magneto-rheological(MR) semi-active suspension system with the controllable damping forces has received more attention in reducing the vibration of a vehicle. However, many control strategies only discussed one or...A magneto-rheological(MR) semi-active suspension system with the controllable damping forces has received more attention in reducing the vibration of a vehicle. However, many control strategies only discussed one or two vibration states of the vehicle based on a quarter-car model or a half vehicle model via MR suspensions. They cannot provide a satisfying whole-vehicle performance on a road test. Hence, a full car vibration model via an MR suspension system is proposed. To reduce the heave, pitch and roll motion of the vehicle body and the vertical vibration of four wheels, a fuzzy hybrid controller for vibration attitude of full car via MR suspensions is proposed. First, a skyhook-fuzzy control scheme is designed to reduce the heave, roll and pitch motion of the vehicle body. Second, a revised ground hook control strategy is adopted to decrease the vertical vibration of the wheels. Finally, a hybrid control scheme based on a fuzzy reasoning method is proposed to tune the hybrid damping parameter, which is suitable for coordination the attitude of the vehicle body and the wheels. A test and control system for the vibration attitude of full car is set up. It is implemented on a car equipped with four MR suspensions. The results on random highway and rough road indicate that the fuzzy hybrid controller can decrease the vibration accelerations of the vehicle body and the wheels to 65%-80% and 80%-90%, respectively. It reduces the automotive vibrations of heave, roll and pitch more effectively than a passive suspension and an MR suspension with a traditional hybrid control scheme so that it achieves better ride comfort and road holding concurrently. This paper proposes a new fuzzy hybrid control(FHC) method for reducing vibration attitude of full car via MR suspensions and develops a road test to evaluate the FHC.展开更多
Fertilizers contribute greatly to high yields but also result in environmental non-point contamination, including the emission of greenhouse gas(N 2O) and eutrophication of water bodies. How to solve this problem has...Fertilizers contribute greatly to high yields but also result in environmental non-point contamination, including the emission of greenhouse gas(N 2O) and eutrophication of water bodies. How to solve this problem has become a serious challenge, especially for China as its high ecological pressure. Controlled-release fertilizer(CRF) has been developed to minimize the contamination while keeping high yield and has become a green fertilizer for agriculture. Several CRFs made with special coating technology were used for testing the fertilizer effects in yield and environment through pot experiment and field trial. The result indicated that the CRFs had higher N use efficiency, thus reducing N loss through leaching and volatilization while keeping higher yields. Comparing with imported standard CRFs, the test on CRFs showed similar fertilizer effect but with much lower cost. CRFs application is becoming a new approach for minimizing non-point contamination in agriculture.展开更多
Some disperse dyes were microencapsulated by means of in- situ polymerization. These microencapsulated disperse dyes was extracted respectively by ethanol under certain conditions. The controlled-release properties of...Some disperse dyes were microencapsulated by means of in- situ polymerization. These microencapsulated disperse dyes was extracted respectively by ethanol under certain conditions. The controlled-release properties of disperse dyes through the shell of microcapsules were measured by spectrophotometer. According to the results, it was drawn that the type of disperse dyes, the auxiliaries contained in disperse dyes, the quantity of system controlling medium used and the core/shell ratio of microcapsules play important roles in controlling the release properties of microcapsules. The different controlled- release properties of microcapsules, which were prepared under given conditions, however, would in turn influence the performance of microcapsules in multiple-transfer printing.展开更多
This paper was to explore the mechanism of single basal application of controlled-release fertilizers for increasing yield of rice (Oryza sativa L.). Pot trials and cylinder trials were carried out from 2002 to 2005...This paper was to explore the mechanism of single basal application of controlled-release fertilizers for increasing yield of rice (Oryza sativa L.). Pot trials and cylinder trials were carried out from 2002 to 2005 to study the influences of single basal application of 3 controlled-release fertilizers on the changes of soil available N, root development, senescence and lodging resistance at late growth stages. Results showed that at 30 days after fertilization, single basal application of controlled-release fertilizers coated with vegetal-substance (CRF1) and polymer materials (CRF3) increased soil available N to 12.0 and 147.9%, respectively, in comparison to split fertilization of rice-specific fertilizer (RSF1). Treatments of the two CRFs obviously benefited the development of root system, resulting in greater rice root weights with extensive distribution and higher root activity. In addition, the two CRF treatments, in comparison to RSF1, enhanced chlorophyll consents of the flag leaves to 9.5 and 15.5%, and soluble protein up to 89.7 and 108.0% respectively. Application of the two CRFs also made the base of rice stems strong and large, declined the proportion of shoot and root, increased root depth index. Though relatively low K rate, single basal application of the CRF3 coated with NH4MgPO4 could also promote the development of root system, enhance root activity and some physiological functions of flag leaves. Based on these results, it was concluded that major mechanisms for increasing rice yield by single basal application of the CRFs should be attributed to grater soil available N supply, superior development of root systems, better nutrient absorption capacity, slower senescence and enhancement of lodging resistance at late stages.展开更多
The equations for fiber suspensions in an evolving mixing layer were solved by the spectral method, and the trajectory and orientation of fibers were calculated based on the slender body theory. The calculated spatial...The equations for fiber suspensions in an evolving mixing layer were solved by the spectral method, and the trajectory and orientation of fibers were calculated based on the slender body theory. The calculated spatial and orientation distributions of fibers are consistent with the experimental ones that were performed in this paper. The relationship between the microstructure of fibers and additional stress was examined. The results show that the spatial and orientation distributions of fibers are heterogeneous because of the influence of coherent vortices in the flow, which leads to the heterogeneity of the additional stress. The degree of heterogeneity increases with the increasing of St number and fiber aspect ratio. The fibers in the flow make the momentum loss thickness of the mixing layer thicker and accelerate the vorticity dispersion.展开更多
Coated controlled-release fertilizers (CRFs) have been widely applied in agriculture due to their increased efficiency. However, the widespread and a lot of coated CRFs application may leave undesired coating residu...Coated controlled-release fertilizers (CRFs) have been widely applied in agriculture due to their increased efficiency. However, the widespread and a lot of coated CRFs application may leave undesired coating residues in the soil due to their slow degradation. Limited information is available on the effects of substantial residual coatings on the soil bacterial community. By adding 0, 5, 10, 20, and 50 times quantities of residual coating from conventional application amount of resin and water-soluble coated CRFs, we studied the responses of soil properties and bacterial community composition to these two residual coatings in black soil. The results showed that the resin and water-soluble coatings did not essentially alter the properties of black soil or cause dramatic changes to bacterial diversity within the test concentration range. The residual resin and water-soluble coatings also did not distinctly alter the relative abundance of the top ten bacteria at phylum level. Heatmap results suggested that the treatments were basically clustered into two groups by concentration rather than types of coating material. Pearson correlation analysis showed that the Simpson's diversity index of the bacterial community was significantly correlated with microbial biomass carbon (MBC, r=0.394, P〈0.05), and the richness index abundance-based coverage estimator (ACE) of the bacterial community was significantly correlated with microbial biomass nitrogen (MBN, t=0.407, P〈0.05). Overall, results of this study suggested that substantial residual resin and water-soluble coatings with 0-50 times quantities of residual coating from conventional application amount of coated CRFs did not generate obviously negative impacts on the bacterial community in black soil.展开更多
基金supported in part by the Fundamental Research Funds for the Central Universities(2572019BB03 and 2572021CG01)the Startup Fund and the Catalyst Fund from Rowan University and the Research Grant(PC 20-22)from the New Jersey Health Foundation from USAthe Grant(DMR-2116353)from the National Science Foundation.
文摘The rheological properties of nanocellulose aqueous suspensions play a critical role in the development of nanocellulose-based bulk materials.High-crystalline,high-aspect ratio,and slender nanofibrillated cellulose(NFC)were extracted from four biomass resources.The cellulose nanofibrils and nanofibril bundles formed inter-connected networks in the NFC aqueous suspensions.The storage moduli of the suspensions with different concentrations were higher than their corresponding loss moduli.As the concentration increased,the storage and loss modulus of NFC dispersion increased.When the shear rate increased to a certain value,there were differences in the changing trend of the rheological behavior of NFC aqueous suspensions derived from different biomass resources and the suspensions with different solid concentrations.NFC dispersion’s storage and loss modulus increased when the temperature rose to nearly 80℃.We hope this study can deepen the understanding of the rheological properties of NFC colloids derived from different biomass resources.
基金provided by the National Key Research and Development Program of China(2018YFD0300904)Anhui Natural Science Foundation(2008085QC119)Key Fund Project of Anhui Department of Education(KJ2019A0176).
文摘One-time application of mixed fertilizer formed by the compounding of two controlled-release nitrogen fertilizers(CRUs)with targeted N supply during the periods from transplantation(TS)to panicle initiation(PI)and from PI to heading(HS)is expected to synchronize the double-peak N demand of rice.However,its effects on the yield and N use efficiency(NUE)of labor-intensive double-cropping rice were unknown.Two targeted CRU(CRU_(A)and CRU_(B))were compounded in five ratios(CRU_(A):CRU_(B)=10:0,7:3,5:5,3:7,and 0:10)to form five mixed fertilizers(BBFs):BBF1-5.A field experiment was performed to investigate the characteristics of N supply in early and late seasons under different BBFs and their effects on N uptake,yield,and ammonia volatilization(AV)loss from paddy fields of double-cropping rice.Conventional high-yield fertilization(CK,three split applications of urea)and zero-N treatments were established as controls.The N supply dropped significantly with the increased compound ratio of CRU_(B)during the period from TS to PI,but increased during the period from PI to HS.With the exception of the period from TS to PI in the late rice season,the N uptake of early and late rice maintained close synchronicity with the N supply of BBFs during the double-peak periods.Excessive N supply(BBF1 and BBF2)in the late rice season during the period from TS to PI increased N loss by AV.The effect of BBF on grain yield increase varied widely between seasons,irrespective of year.Among the BBFs,the BBF2 treatment of early rice not only stabilized the spikelets per panicle but also ensured a high number of effective panicles by promoting N uptake during the period from TS to PI and a high grain-filling percentage by appropriately reducing the N supply at the later PI stage,resulting in the highest rice yield.While stabilizing the effective panicle number,the BBF4 treatment of late rice increased the number of spikelets per panicle by promoting N uptake during the period from PI to HS,resulting in the highest rice yield.The two-year average yield and apparent N recovery efficiency of the BBF2 treatment during the early rice season were 9.6 t ha 1 and 45.3%,while those of late rice in BBF4 were 9.6 t ha 1 and 43.0%,respectively.The yield and NUE indexes of BBF2 in early rice and BBF4 in late rice showed no significant difference from those of CK.The AVs of BBF2 during the early rice season and of BBF4 during the late rice season were 50.0%and 76.8%lower,respectively,than those of CK.BBF2 and BBF4 could effectively replace conventional urea split fertilization in early and late rice seasons,ensuring rice yield and NUE and reducing AV loss in paddy fields.
文摘Silica aerogel with different hydrophilicities were prepared from tetramethoxysilane,Methymethoxysilane,tetramethoxysilane-propyltrimethoxysilane,or tetramethoxysilane-phenyltrimethoxysilane mixtures via supercritical drying process(labelled as TMOS-AG Me-TMOS-AG,Pr-TMOS-AG,or Ph-TMOS-AG,respectively).Three fragrances,including geraniol,ethyl vanillin,and menthol,were loaded to TMOS-AG.The thermal analysis confirmed all loading fragrances are stable until over 200℃.And among all fragrances,geraniol presented the maximum loading contents(L_(m)).Concentration dependences indicated the geraniol was mono layer absorbed.Py-GC/MS of geraniol in TMOS-AG under both N_(2)and mimic air atmosphere(90%N_(2)and 10%O_(2))confirmed that loaded geraniol could be thermally controlled-released beginning at 200℃.As N_(2)absorption confirmed,even absorption/desorption equilibrium constant(k)was determined mainly by hydrophilicity of silica aerogels,and the maximum loading contents(L_(m))were influenced more by the pore size.Due to mono layered absorption,bigger pores usually give less specific areas and less absorbing sites for geraniol,and then present lower L_(m).
基金the Key R&D Plan of Shaanxi Province Project,China(2023-YBNY-041)the Doctoral Graduates and Postdoctoral Researchers from Shanxi Province Come to Work to Reward Scientific Research Projects,China(SXBYKY2022119)the Key Laboratory Project of Shanxi Province,China(202001-4)。
文摘A mixture of controlled-release urea and normal urea(CRUNU)is an efficient nitrogen(N)fertilizer type,but little is known about its effects on stem lodging resistance,grain yield,and yield stability of wheat.In this study,a 4-year field experiment(from 2017 to 2021)was conducted to analyze the effects of N fertilizer types(CRUNU and normal urea(NU))and application rates(low level(L),135 kg ha^(–1);medium level(M),180 kg ha^(–1);high level(H),225 kg ha^(–1))on population lodging resistance,basal internode strength,lignin content and synthetase activity,stem lodging resistance,grain yield,and yield stability of wheat.Our results showed that the two N fertilizer types had the highest lodging rate under high N application rates,and the M-CRUNU treatment showed the lowest lodging rate.Compared with NU,CRUNU improved the wheat population lodging resistance under the three N application rates,mainly related to improving wheat population characteristics and breaking the strength of the second basal internode.Correlation analysis showed that the breaking strength of the second basal internode was related to the physical characteristics,chemical components,and micro-structure of the internode.Compared with NU,CRUNU significantly increased wheat grain yield by 4.47,14.62,and 3.12%under low,medium,and high N application rates,respectively.In addition,CRUNU showed no significant difference in grain yield under medium and high N application rates,but it presented the highest yield stability under the medium N application rate.In summary,CRUNU,combined with the medium N application rate,is an efficient agronomic management strategy for wheat production.
基金supported by the Natural Science Foundation of Jiangsu Province(BK20200539)Postdoctoral Research Foundation of China(2019M661863)Jiangsu Provincial Key Research and Development Program(BE2019377,BE2019343)。
文摘Controlled-release urea(CRU)is widely reported to supply crop nitrogen(N)demand with one basal application,thus effectively replacing split applications of urea without diminishing grain yield and N use efficiency(NUE).However,its use for replacement for high-yield split applications of urea(CK)for rice is untested.In addition,the degree to which greenhouse gas(GHG)emissions in rice systems are affected when CRU is substituted for CK remains unclear.During 2017 and 2018,we sampled plant growth and gas emissions in a rice paddy field treated with three CRU types(sulfur-coated urea[SCU],polymer-coated urea[PCU],and bulk blended CRU[BBU])applied via two methods(surface broadcasting on the soil and subsurface banding at 5 cm depth),with CK as a control.The three CRUs led to different soil NH_(4)^(+)-N dynamics,and the N supply pattern under BBU was more beneficial for rice seedling establishment than under SCU and PCU,resulting in grain yield and NUE comparable to those under CK.CRU type showed no significant effect on either CH_(4) emissions or N_(2)O emissions,and broadcast CRUs exhibited significantly higher total GHG emissions than CK.However,banded CRUs significantly reduced the total GHG emissions in comparison with broadcast CRUs,by 9.2%averaged across the two years.Reduced CH_(4) emissions,particularly during the period prior to the middle drainage,contributed largely to the GHG difference.With comparably high grain yield and low total GHG emissions,banded BBU showed a low yield-scaled GHG(GHG emissions divided by grain yield)comparable to that under CK in both years.Overall,our study suggested that N management synchronized with rice demand and contributing to a high NUE tended to minimize yield-scaled GHG.Broadcast CRU can hardly substitute for CK in terms of either grain yield or GHG emissions,but banded BBU is a promising N management strategy for sustaining rice production while minimizing environmental impacts.
基金This work was supported by National Natural Science Foundation of China(No.12075304)Natural Science Foundation of Shanghai(No.22ZR1442100)National Key Research and Development Program of China(No.2022YFB3503904).
文摘X-ray photon correlation spectroscopy(XPCS)has emerged as a powerful tool for probing the nanoscale dynamics of soft condensed matter and strongly correlated materials owing to its high spatial resolution and penetration capabilities.This technique requires high brilliance and beam coherence,which are not directly available at modern synchrotron beamlines in China.To facilitate future XPCS experiments,we modified the optical setup of the newly commissioned BL10U1 USAXS beamline at the Shanghai Synchrotron Radiation Facility(SSRF).Subsequently,we performed XPCS measurements on silica suspensions in glycerol,which were opaque owing to their high concentrations.Images were collected using a high frame rate area detector.A comprehensive analysis was performed,yielding correlation functions and several key dynamic parameters.All the results were consistent with the theory of Brownian motion and demonstrated the feasibility of XPCS at SSRF.Finally,by carefully optimizing the setup and analyzing the algorithms,we achieved a time resolution of 2 ms,which enabled the characterization of millisecond dynamics in opaque systems.
基金the National Natural Science Foundation of China(Grant Numbers 52072157,52002156,52202471)Natural Science Foundation of Jiangsu Province(Grant Number BK20200911)+2 种基金Chongqing Key Laboratory of Urban Rail Transit System Integration and Control Open Fund(Grant Number CKLURVIOM_KFKT_2023001)Jiangsu Funding Program for Excellent Postdoctoral Talent(Grant Number 2022ZB659)State Key Laboratory of Advanced Design and Manufacturing Technology for Vehicle,Hunan University(Grant Number 82315004).
文摘This paper addresses the impact of vertical vibration negative effects,unbalanced radial forces generated by the static eccentricity of the hub motor,and road excitation on the suspension performance of Hub Motor Driven Vehicle(HMDV).A dynamic inertial suspension based on Active Disturbance Rejection Control(ADRC)is proposed,combining the vertical dynamic characteristics of dynamic inertial suspension with the features of ADRC,which distinguishes between internal and external disturbances and arranges the transition process.Firstly,a simulation model of the static eccentricity of the hub motor is established to simulate the unbalanced radial electromagnetic force generated under static eccentricity.A quarter-vehicle model of an HMDV with a controllable dynamic inertial suspension is then constructed.Subsequently,the passive suspension model is studied under different grades of road excitation,and the impact mechanism of suspension performance at speeds of 0–20 m/s is analyzed.Next,the three main components within the ADRC controller are designed for the second-order controlled system,and optimization algorithms are used to optimize its internal parameters.Finally,the performance of the traditional passive suspension,the PID-based controllable dynamic inertial suspension,and the ADRC-based controllable dynamic inertial suspension are analyzed under different road inputs.Simulation results show that,under sinusoidal road input,the ADRC-based controllable dynamic inertial suspension exhibits a 52.3%reduction in the low-frequency resonance peak in the vehicle body acceleration gain diagram compared to the traditional passive suspension,with significant performance optimization in the high-frequency range.Under random road input,the ADRC-based controllable dynamic inertial suspension achieves a 29.53%reduction in the root mean square value of vehicle body acceleration and a 14.87%reduction in dynamic tire load.This indicates that the designed controllable dynamic inertial suspension possesses excellent vibration isolation performance.
基金supported by the Imperial College Research Fellowship(ICRF 2022-2026)。
文摘Active suspension systems(ASSs)have been proposed and developed for a few decades,and have now once again become a thriving topic in both academia and industry,due to the high demand for driving comfort and safety and the compatibility of ASSs with vehicle electrification and autonomy.Existing review papers on ASSs mainly cover dynamics modeling and robust control;however,the gap between academic research outcomes and industrial application requirements has not yet been bridged,hindering most ASS research knowledge from being transferred to vehicle companies.This paper comprehensively reviews advances in ASSs for road vehicles,with a focus on hardware structures and control strategies.In particular,state-of-the-art ASSs that have been recently adopted in production cars are discussed in detail,including the representative solutions of Mercedes active body control(ABC)and Audi predictive active suspension;novel concepts that could become alternative candidates are also introduced,including series active variable geometry suspension,and the active wheel-alignment system.ASSs with compact structure,small mass increment,low power consumption,high-frequency response,acceptable economic costs,and high reliability are more likely to be adopted by car manufacturers.In terms of control strategies,the development of future ASSs aims not only to stabilize the chassis attitude and attenuate the chassis vibration,but also to enable ASSs to cooperate with other modules(e.g.,steering and braking)and sensors(e.g.,cameras)within a car,and even with high-level decision-making(e.g.,reference driving speed)in the overall transportation system-strategies that will be compatible with the rapidly developing electric and autonomous vehicles.
基金partly funded by the Department of Science and Technology Fund for Improvement of S&T Infrastructure (Grant No. SR/FST/LS-I/2018/125)。
文摘Tissue culture techniques were used to produce large amounts of bioactive compounds with medicinal potential, overcoming space and time constraints for cancer prevention. Rice callus suspension cultures(RCSC) and seed extracts prepared from aromatic rice varieties were used to evaluate the cytotoxic impact on human colon and lung cancer cell lines, as well as a normal control cell line, using Taxol as a positive control. RCSC and seed extracts from two Indian aromatic rice varieties were applied at different concentrations to treat the cancer cell lines and normal lung fibroblasts over varying time intervals. Apoptosis was assessed in 1:5 dilutions of the A549 and HT-29 cell lines treated with RCSC for 72 h, using propidium iodide staining and flow cytometry. RCSC showed a more potent cytotoxic effect than seed extracts with minimal effect on the normal cell line, in contrast to Taxol. Confocal microscopy and flow cytometry further confirmed the apoptotic effect of RCSC. Gas chromatography-mass spectrometry-based metabolic profiling identified metabolites involved in cytotoxicity and highlighted altered pathways. RCSC is proposed as an alternative source for the development of novel anticancer drugs with reduced side effects.
基金Supported by Tianjin Key Medical Discipline Construction Project(No.TJYXZDXK-016A).
文摘AIM:To investigate the symmetry of upper eyelid in patients with unilateral mild and moderate blepharoptosis who underwent unilateral minimally invasive combined fascia sheath(CFS)suspension.METHODS:A retrospective study of patients who underwent unilateral minimally invasive CFS suspension surgery between January 2018 and December 2021.Inclusion criteria included unilateral mild and moderate ptosis,good levator muscle function(>9 mm)and follow-up of at least 6mo.Pre-and post-operative symmetry was graded subjectively for marginal reflex distance 1(MRD1),tarsal platform show(TPS)and eyebrow fat span(BFS).A t-test was used to evaluate MRD1,TPS and BFS asymmetry by calculating delta values.The Bézier curve tool of the Image J software was used to extract the upper eyelid contours,where the symmetry was measured by the percentage of overlapping curvatures(POC).RESULTS:Totally 105 patients(105 eyelids)were included(mild group,n=84;moderate group,n=21).Postoperatively,all patients increased MRD1 and decreased TPS in the ptotic eye while maintaining unchanged BFS.The asymmetric delta value for MRD1 was measured to be 1.48±0.86 preoperatively,and it decreased to 0.58±0.67 postoperatively in all cases(P=0.0004).In patients with mild ptosis,the asymmetry value of TPS fell significantly from 1.15±0.62 to 0.68±0.38(P=0.0187).The symmetry of the upper eyelid contour increased in all subgroups of patients,with a POC of 59.39%±13.45%preoperatively and POC of 78.29%±13.80%postoperatively.CONCLUSION:Minimally invasive CFS suspension is proved to be an effective means of improving the symmetry of unilateral ptosis in terms of MRD1(all subgroups),POC(all subgroups)and TPS(only mild group),whereas BFS is unaffected.
基金Supported by National Natural Science Foundation of China(Grant No.52272387)State Key Laboratory of Mechanical Behavior and System Safety of Traffic Engineering Structures,Shijiazhuang Tiedao University of China(Grant No.KF2020-29)Beijing Municipal Science and Technology Commission through Beijing Nova Program of China(Grant No.20230484475).
文摘This paper presents an integrated control scheme for enhancing the ride comfort and handling performance of a four-wheel-independent-drive electric vehicle through the coordination of active suspension system(ASS)and anti-lock braking system(ABS).First,a longitudinal-vertical coupled vehicle dynamics model is established by integrating a road input model.Then the coupling mechanisms between longitudinal and vertical vehicle dynamics are analyzed.An ASS-ABS integrated control system is proposed,utilizing an H∞controller for ASS to optimize load transfer effect and a neural network sliding mode control for ABS implementation.Finally,the effectiveness of the proposed control scheme is evaluated through comprehensive tests conducted on a hardware-in-loop(HIL)test platform.The HIL test results demonstrate that the proposed control scheme can significantly improve the braking performance and ride comfort compared to conventional ABS control methods.
文摘This paper addresses the sampled-data multi-objective active suspension control problem for an in-wheel motor driven electric vehicle subject to stochastic sampling periods and asynchronous premise variables.The focus is placed on the scenario that the dynamical state of the half-vehicle active suspension system is transmitted over an in-vehicle controller area network that only permits the transmission of sampled data packets.For this purpose,a stochastic sampling mechanism is developed such that the sampling periods can randomly switch among different values with certain mathematical probabilities.Then,an asynchronous fuzzy sampled-data controller,featuring distinct premise variables from the active suspension system,is constructed to eliminate the stringent requirement that the sampled-data controller has to share the same grades of membership.Furthermore,novel criteria for both stability analysis and controller design are derived in order to guarantee that the resultant closed-loop active suspension system is stochastically stable with simultaneous𝐻2 and𝐻∞performance requirements.Finally,the effectiveness of the proposed stochastic sampled-data multi-objective control method is verified via several numerical cases studies in both time domain and frequency domain under various road disturbance profiles.
文摘Steel truss suspension bridges are prone to developing defects after prolonged use.These defects may include corrosion of the main cable or the steel truss.To ensure the normal and safe functioning of the suspension bridge,it is necessary to inspect for defects promptly,understand the cause of the defect,and locate it through the use of inspection technology.By promptly addressing defects,the suspension bridge’s safety can be ensured.The author has analyzed the common defects and causes of steel truss suspension bridges and proposed specific inspection technologies.This research is intended to aid in the timely discovery of steel truss suspension bridge defects.
基金Shandong Province Traditional Chinese Medicine Science and Technology Project“Effects of Buccal Acupuncture on PGF2α,5-HT,and Uterine Hemodynamics in Patients with Primary Dysmenorrhea”(M-2022240)“Effects of the Combination of Oxycodone and Difference Anesthetic Drugs on Postoperative Cognitive Function and Inflammation-Related Serological Indicators in Elderly ERCP Patients”(ezmr2023-037)。
文摘Objective:To evaluate the clinical advantages of laparoscopic transverse abdominal wall suspension in treating pelvic organ prolapse.Methods:Sixty patients diagnosed with moderate to severe pelvic organ prolapse and underwent surgical treatment in our hospital between January 2022 and December 2023 were selected.According to different surgical methods,they were divided into an observation group(given laparoscopic transverse abdominal wall suspension)and a control group(given transvaginal mesh implantation),with 30 subjects/group.The data on perioperative-related indicators,quality of life scores,postoperative recurrence,and complications of the two groups of patients were collected.Results:The postoperative hospitalization days and intraoperative bleeding volume of the observation group were significantly lower than those of the control group,but had longer operation time than that of the control group(P<0.05).The differences between the two groups were statistically significant 6 months after surgery,and the Pelvic Floor Disease Quality of Life Impact Questionnaire(PFIQ-7)score of the observation group was significantly higher than the control group(P<0.05).Both groups of patients completed 12 months of follow-up without any postoperative recurrence.The number of complications in the observation group was slightly lower than that of the control group(P>0.05).Conclusion:Laparoscopic transverse abdominal wall suspension was more effective in treating pelvic organ prolapse and is an ideal surgical procedure.
基金supported by National Natural Science Foundation of China (Grant No. 60674097, Grant No. 60804018)Visiting Scholar Foundation of Key Laboratory of Optoelectronic Technology and Systems of Ministry of Education in Chongqing University of China, and Chongqing Municipal Natural Science Foundation of China (Grant No. 2008BB2407, Grant No. 2009AC3079, Grant No. 2009BB3416)
文摘A magneto-rheological(MR) semi-active suspension system with the controllable damping forces has received more attention in reducing the vibration of a vehicle. However, many control strategies only discussed one or two vibration states of the vehicle based on a quarter-car model or a half vehicle model via MR suspensions. They cannot provide a satisfying whole-vehicle performance on a road test. Hence, a full car vibration model via an MR suspension system is proposed. To reduce the heave, pitch and roll motion of the vehicle body and the vertical vibration of four wheels, a fuzzy hybrid controller for vibration attitude of full car via MR suspensions is proposed. First, a skyhook-fuzzy control scheme is designed to reduce the heave, roll and pitch motion of the vehicle body. Second, a revised ground hook control strategy is adopted to decrease the vertical vibration of the wheels. Finally, a hybrid control scheme based on a fuzzy reasoning method is proposed to tune the hybrid damping parameter, which is suitable for coordination the attitude of the vehicle body and the wheels. A test and control system for the vibration attitude of full car is set up. It is implemented on a car equipped with four MR suspensions. The results on random highway and rough road indicate that the fuzzy hybrid controller can decrease the vibration accelerations of the vehicle body and the wheels to 65%-80% and 80%-90%, respectively. It reduces the automotive vibrations of heave, roll and pitch more effectively than a passive suspension and an MR suspension with a traditional hybrid control scheme so that it achieves better ride comfort and road holding concurrently. This paper proposes a new fuzzy hybrid control(FHC) method for reducing vibration attitude of full car via MR suspensions and develops a road test to evaluate the FHC.
文摘Fertilizers contribute greatly to high yields but also result in environmental non-point contamination, including the emission of greenhouse gas(N 2O) and eutrophication of water bodies. How to solve this problem has become a serious challenge, especially for China as its high ecological pressure. Controlled-release fertilizer(CRF) has been developed to minimize the contamination while keeping high yield and has become a green fertilizer for agriculture. Several CRFs made with special coating technology were used for testing the fertilizer effects in yield and environment through pot experiment and field trial. The result indicated that the CRFs had higher N use efficiency, thus reducing N loss through leaching and volatilization while keeping higher yields. Comparing with imported standard CRFs, the test on CRFs showed similar fertilizer effect but with much lower cost. CRFs application is becoming a new approach for minimizing non-point contamination in agriculture.
文摘Some disperse dyes were microencapsulated by means of in- situ polymerization. These microencapsulated disperse dyes was extracted respectively by ethanol under certain conditions. The controlled-release properties of disperse dyes through the shell of microcapsules were measured by spectrophotometer. According to the results, it was drawn that the type of disperse dyes, the auxiliaries contained in disperse dyes, the quantity of system controlling medium used and the core/shell ratio of microcapsules play important roles in controlling the release properties of microcapsules. The different controlled- release properties of microcapsules, which were prepared under given conditions, however, would in turn influence the performance of microcapsules in multiple-transfer printing.
文摘This paper was to explore the mechanism of single basal application of controlled-release fertilizers for increasing yield of rice (Oryza sativa L.). Pot trials and cylinder trials were carried out from 2002 to 2005 to study the influences of single basal application of 3 controlled-release fertilizers on the changes of soil available N, root development, senescence and lodging resistance at late growth stages. Results showed that at 30 days after fertilization, single basal application of controlled-release fertilizers coated with vegetal-substance (CRF1) and polymer materials (CRF3) increased soil available N to 12.0 and 147.9%, respectively, in comparison to split fertilization of rice-specific fertilizer (RSF1). Treatments of the two CRFs obviously benefited the development of root system, resulting in greater rice root weights with extensive distribution and higher root activity. In addition, the two CRF treatments, in comparison to RSF1, enhanced chlorophyll consents of the flag leaves to 9.5 and 15.5%, and soluble protein up to 89.7 and 108.0% respectively. Application of the two CRFs also made the base of rice stems strong and large, declined the proportion of shoot and root, increased root depth index. Though relatively low K rate, single basal application of the CRF3 coated with NH4MgPO4 could also promote the development of root system, enhance root activity and some physiological functions of flag leaves. Based on these results, it was concluded that major mechanisms for increasing rice yield by single basal application of the CRFs should be attributed to grater soil available N supply, superior development of root systems, better nutrient absorption capacity, slower senescence and enhancement of lodging resistance at late stages.
基金The project supported by the Doctoral Program of Higher Education in China(20030335001)
文摘The equations for fiber suspensions in an evolving mixing layer were solved by the spectral method, and the trajectory and orientation of fibers were calculated based on the slender body theory. The calculated spatial and orientation distributions of fibers are consistent with the experimental ones that were performed in this paper. The relationship between the microstructure of fibers and additional stress was examined. The results show that the spatial and orientation distributions of fibers are heterogeneous because of the influence of coherent vortices in the flow, which leads to the heterogeneity of the additional stress. The degree of heterogeneity increases with the increasing of St number and fiber aspect ratio. The fibers in the flow make the momentum loss thickness of the mixing layer thicker and accelerate the vorticity dispersion.
基金supported by the International Scientific and Technological Cooperation Projects of China (2015DFA20790)the National Natural Science Foundation of China (21577172,41501322)the National Basic Research Program (973 program) of China (2013CB127406)
文摘Coated controlled-release fertilizers (CRFs) have been widely applied in agriculture due to their increased efficiency. However, the widespread and a lot of coated CRFs application may leave undesired coating residues in the soil due to their slow degradation. Limited information is available on the effects of substantial residual coatings on the soil bacterial community. By adding 0, 5, 10, 20, and 50 times quantities of residual coating from conventional application amount of resin and water-soluble coated CRFs, we studied the responses of soil properties and bacterial community composition to these two residual coatings in black soil. The results showed that the resin and water-soluble coatings did not essentially alter the properties of black soil or cause dramatic changes to bacterial diversity within the test concentration range. The residual resin and water-soluble coatings also did not distinctly alter the relative abundance of the top ten bacteria at phylum level. Heatmap results suggested that the treatments were basically clustered into two groups by concentration rather than types of coating material. Pearson correlation analysis showed that the Simpson's diversity index of the bacterial community was significantly correlated with microbial biomass carbon (MBC, r=0.394, P〈0.05), and the richness index abundance-based coverage estimator (ACE) of the bacterial community was significantly correlated with microbial biomass nitrogen (MBN, t=0.407, P〈0.05). Overall, results of this study suggested that substantial residual resin and water-soluble coatings with 0-50 times quantities of residual coating from conventional application amount of coated CRFs did not generate obviously negative impacts on the bacterial community in black soil.