Bud dormancy is a complex physiological process of perennial woody plants living in temperate regions,and it can be affected by various phytohormones.Cytokinin oxidase/dehydrogenases(CKXs)are a group of enzymes essent...Bud dormancy is a complex physiological process of perennial woody plants living in temperate regions,and it can be affected by various phytohormones.Cytokinin oxidase/dehydrogenases(CKXs)are a group of enzymes essential for maintaining cytokinin homeostasis,yet a comprehensive analysis of these enzymes in peach remains lacking.Here,a total of 51 CKX members from different species,including six from peach,eleven from apple,nine from poplar,seven from Arabidopsis,eight from strawberry,and ten from rice,were identified using the Simple HMM Search tool of TBtools and a BLASTP program and classified into four groups using phylogenetic analysis.Conserved motif and gene structure analysis of these 51 CKX members showed that 10 conserved motifs were identified,and each CKX gene contained at least two introns.Cis-element analysis of PpCKXs showed that all PpCKX genes have light-responsive elements and at least one hormone-responsive element.The changed relative expression levels of six PpCKX genes in peach buds from endodormancy to bud-break were observed by qRT-PCR.Among them,the expression trend of PpCKX6 was almost opposite that of PpEBB1,a positive bud-break regulator in woody plants,around the bud-break stage.Y1H,EMSA,and dual-luciferase assays indicated that PpEBB1negatively regulated PpCKX6 through direct binding to a GCC box-like element located in the promoter region of PpCKX6.In addition,a transient assay showed that overexpression of PpCKX6 delayed the bud-break of peach.These results indicate that the PpCKX genes play an essential role in the dormancy-regrowth process,and Pp CKX6may act downstream of PpEBB1 directly to regulate the bud-break process,which further improves the hormoneregulatory network of dormancy-regrowth of woody plants,and provides new insights for molecular breeding and genetic engineering of peach.展开更多
Despite standard treatment for non-small cell lung cancer(NSCLC)being surgical resection,cancer recurrence and complications,such as induction of malignant pleural effusion(MPE)and significant postoperative pain,usual...Despite standard treatment for non-small cell lung cancer(NSCLC)being surgical resection,cancer recurrence and complications,such as induction of malignant pleural effusion(MPE)and significant postoperative pain,usually result in treatment failure.In this study,an alginate-based hybrid hydrogel(SOG)is developed that can be injected into the resection surface of the lungs during surgery.Briefly,endoplasmic reticulum-modified liposomes(MSLs)pre-loaded with the signal transducer and activator of transcription 3(STAT3)small interfering RNA and lidocaine hydrochloride are encapsulated in SOG.Once applied,MSLs strongly downregulated STAT3 expression in the tumor microenvironment,resulting in the apoptosis of lung cancer cells and polarization of tumor-associated macrophages towards the M1-like phenotype.Meanwhile,the release of lidocaine hydrochloride(LID)was beneficial for pain relief and natural killer cell activation.Our data demonstrated MSL@LID@SOG not only efficiently inhibited tumor growth but also potently improved the quality of life,including reduced MPE volume and pain relief in orthotopic NSCLC mouse models,even with a single administration.MSL@LID@SOG shows potential for comprehensive clinical management upon tumor resection in NSCLC,and may alter the treatment paradigms for other cancers.展开更多
With rapid progress,organic solar cells(OSCs)are getting closer to the target of real application.However,the stability issue is still one of the biggest challenges that have to be resolved.Especially,the thermal stab...With rapid progress,organic solar cells(OSCs)are getting closer to the target of real application.However,the stability issue is still one of the biggest challenges that have to be resolved.Especially,the thermal stability of OSCs is far from meeting the requirements of the application.Here,based on the layer-by-layer(LBL)process and by utilizing the dissolubility nature of solvent and materials,binary inverted OSCs(ITO/AZO/PM6/BTP-eC9/MoO3/Ag)with comb shape active morphology are fabricated.High efficiency of 17.13%and simultaneous superior thermal stability(with 93%of initial efficiency retained in~9:00 h under 85℃in N_(2))are demonstrated,showing superior stability to reference cells.The enhancements are attributed to the formed optimal comb shape of the active layer,which could provide a larger D/A interface,thus more charge carriers,render the active blend a more stable morphology,and protect the electrode by impeding ion's migration and corrosion.To the best of our knowledge,this is the best thermal stability of binary OSCs reported in the literature,especially when considering the high efficiency of over 17%.展开更多
Due to the high structural flexibility and controllable thermal expansion,cubic double ReO_(3)-type negative thermal expansion(NTE)fluorides provide a solution for solving the prominent phenomenon of thermal expansion...Due to the high structural flexibility and controllable thermal expansion,cubic double ReO_(3)-type negative thermal expansion(NTE)fluorides provide a solution for solving the prominent phenomenon of thermal expansion mismatch between materials.However,the expensive raw materials and complex synthesis steps limit its practical application.In this work,we have designed a more advantageous method for the synthesis of NTE material CaZrF_(6),and it is expected to be generalized to the synthesis of other double ReO_(3)-fluorides.Intriguingly,a new orthorhombic phase CaZrF_(6) has been synthesized via this method in a lower temperature.Unlike the strong isotropic NTE of the cubic phase CaZrF_(6),the orthorhombic phase shows the strong anisotropic positive thermal expansion(PTE).The combined analysis of temperature-dependent X-ray diffraction(XRD),Raman spectra,and first-principles calculations shows that the low frequency phonon vibration mode with negative Grüneisen parameter in cubic CaZrF_(6) are strongly correlated with the transverse thermal vibration of F atoms and dominates the NTE of the material.展开更多
For the problem that when wheat is sucked up by the air suction method,the seeds are aligned in a small area,making it difficult for the contact seed cleaning mechanism to clean the seeds.The mechanism of seed cleanin...For the problem that when wheat is sucked up by the air suction method,the seeds are aligned in a small area,making it difficult for the contact seed cleaning mechanism to clean the seeds.The mechanism of seed cleaning airflow on wheat seed was studied,the flow velocity distribution relationship of the jet section was defined,the mathematical model of the jet velocity of circular and plane sections was established,and the key factors that could have a significant influence on seed cleaning effect were explored.A non-contact positive pressure air flow seed cleaning method was proposed.After theoretical calculations,it is concluded that the core section lengths of the circular section jet and the inline jet are 24.8 mm and 28.8 mm,respectively.The clearing distance is set to 20 mm.Through the single-factor test,the best air tube nozzle shape was clarified as a vertical inline nozzle.The angle of seed cleaning,the air velocity of seed cleaning,and the negative supply pressure were selected as influencing factors,and the seed leakage index,seed reabsorption index,and seed qualification index as the evaluation indicators to conduct a 3-factor 5-horizontal rotation test.A mathematical regression model of influencing factors and evaluation indexes was established to analyze the influence of these factors and indexes.The optimal operation parameters were obtained as the seed cleaning Angle of 19°,the seed cleaning air velocity of 58 m/s,and the negative pressure of 8.5 kPa.Under the optimal parameters,the seed leakage suction index is 8.23%,the seed reabsorption index is 0.33%,and the seed qualification index is 91.44%,which meets the design requirements.展开更多
An adequate and uniform press wheel pressure is crucial for the homogeneous development of a crop,as it affects actual seeding depth and germination rate.The problems of uneven compaction of seed furrow and consistenc...An adequate and uniform press wheel pressure is crucial for the homogeneous development of a crop,as it affects actual seeding depth and germination rate.The problems of uneven compaction of seed furrow and consistency of seeding depth can be caused by the pressure fluctuation of the coil-spring pressure control device(CPCD)when the no-till planter is working on the unplowed ground.In this study,a pneumatic pressure control device(PPCD)was designed for the no-till planter,the key structural parameters of air spring for press wheel pressure(PWP)stability were determined by theoretical analysis and parameter calculation.Using the gas-structure coupling finite element simulation method(FESM),the piston radius,piston angle,and cord angle of the air spring are selected as the test factors,and the vertical stiffness was used as the test index to carry out the quadratic rotation orthogonal combination test to establish the regression model of test index and factor.The bench test of the PPCD was carried out under the optimal parameter combination,piston radius of 27.2 mm,piston angle of 11.7°,and cord angle of 30.0°.The vertical stiffness verification test showed that the simulation test was consistent with the bench test result,the vertical stiffness simulation error was 7.1%,and the internal air pressure simulation error was 3.0%;The control response test showed that the average response time of the air spring inflating and deflating was 0.80 s,the maximum overshoot was 4.33%during inflation,and no pressure overshoot during deflation;Under the condition of-40-40 mm surface relief height,the PPCD could effectively reduce the pressure fluctuation compared with the CPCD,and the average reduction of the pressure fluctuation was about 25.1%.展开更多
Protonic ceramic electrolysis cell(PCEC)is a promising technology for production of pure dry hydrogen due to the low operating temperature and high efficiency.One of the obstacles for commercialization of PCEC technol...Protonic ceramic electrolysis cell(PCEC)is a promising technology for production of pure dry hydrogen due to the low operating temperature and high efficiency.One of the obstacles for commercialization of PCEC technology is the poor performance and insufficient long-term durability of the oxygen electrode.In this study,we address the above challenge by designing a LaCoO_(3)(LC)catalyst infiltrated porous BaZr_(0.8)Y_(0.2)O_(3)−δ(BZY20)backbone electrode(LC-BZY20).The performance and durability of the LC-BZY20 electrode are investigated on symmetrical cells using electrochemical impedance spectroscopy(EIS).The total electrode polarization resistance(RP)values of the electrode are 0.56,1.24,2.18,and 2.90Ωcm2 in 3vol%humidified synthetic air at 600,550,500,and 450℃,respectively,indicating good electrochemical performance of the LC-BZY20 electrode.Furthermore,the LC-BZY20 electrode displays good stability,without significant performance degradation when tested at 600℃ in 10vol%humidified air for 900h.We further study the influence of oxygen partial pressure(PO_(2))and steam partial pressure(P_(H_(2)O))on the response of the EIS data,and propose a set of chemical and electrochemical processes involved in the steam splitting reaction in the LC-BZY20 electrode.展开更多
Response gene to complement 32 (RGC-32) is a cell cycle regulator involved in the proliferation, differentiation and migration of cells and has also been implicated in angiogenesis. Here we show that RGC-32 expressi...Response gene to complement 32 (RGC-32) is a cell cycle regulator involved in the proliferation, differentiation and migration of cells and has also been implicated in angiogenesis. Here we show that RGC-32 expression in macrophages is induced by IL-4 and reduced by LPS, indicating a link between RGC-32 expression and M2 polarization. We demonstrated that the increased expression of RGC-32 is characteristic of alternatively activated macrophages, in which this protein suppresses the production of pro-inflammatory cytokine IL-6 and promotes the production of the anti-inflammatory mediator TGF-β. Consistent with in vitro data, tumor-associated macrophages (TAMs) express high levels of RGC-32, and this expression is induced by tumor-derived ascitic fluid in an M-CSF- and/or IL-4-dependent manner. Collectively, these results establish RGC-32 as a marker for M2 macrophage polarization and indicate that this protein is a potential target for cancer immunotherapy, targeting tumor-associated macrophages.展开更多
In view of the difficulties in weeding and plant protection in the middle and late period of maize planting,this paper proposed a self-propelled thermal fogger chassis.According to the theoretical calculation and agro...In view of the difficulties in weeding and plant protection in the middle and late period of maize planting,this paper proposed a self-propelled thermal fogger chassis.According to the theoretical calculation and agronomic requirements for maize planting,the structure and working principles of the self-propelled thermal fogger chassis were introduced.On this basis,the multi-body dynamics model of chassis structure was established,and the chassis traction,steering and obstacle surmounting performances were also analyzed.Then the rationality and the feasibility of the design were verified through the furrow running test and test equipped with thermal fogger.Test results showed that,the traction performance improves with the decrease of soil deformation index and increase of cohesion,and when track pre-tensioning force was about 1000 N,the machine had a good traction performance;with the decrease of the soil deformation index and the increase of cohesive force,the stability of the single side brake turn of the chassis becomes better;on the contrary,with the increase of the tightness of the crawler,the steering radius turns smaller and the steering stability becomes worse.Under heavy clay,with the pre-tensioning of 1000 N,the machine has better steering stability and smaller turning radius.The obstacle-surmounting simulation result shows that on sandy soil road,the maximum climbing angle for the chassis is 42°,the height of vertical obstacle crossing is 170 mm and the trench width is 440 mm.The study provides a reference for the design of plant protection machinery in the middle and late stages of maize planting.展开更多
Successful human pregnancy requires the maternal immune system to recognize and tolerate the semi-allogeneic fetus. Myeloid-derived suppressor cells (MDSCs), which are capable of inhibiting T-cell responses, are hig...Successful human pregnancy requires the maternal immune system to recognize and tolerate the semi-allogeneic fetus. Myeloid-derived suppressor cells (MDSCs), which are capable of inhibiting T-cell responses, are highly increased in the early stages of pregnancy. Although recent reports indicate a role for MDSCs in fetal-maternal tolerance, little is known about the expansion of MDSCs during pregnancy. In the present study, we demonstrated that the trophoblast cell line HTR8/SVneo could instruct peripheral CD14+ myelomonocytic cells toward a novel subpopulation of MDSCs, denoted as CD 14 + H LA-DR-/=~w cells, with suppressive activity and increased expression of I DO 1, ARG- 1, a nd COX2. After interaction with HTR8/SVneo cells, CD14+ myelomonocytic cells secrete high levels of CCL2, promoting the expression of signal transducer and activator of transcription 3. We utilized a neutralizing monoclonal antibody to reveal the prominent role of CCL2 in the induction of CD14+HLA-DR-/low MDSCs. In combination, the results of the present study support a novel role for the cross-talk between the trophoblast cell line HTR8/SVneo and maternal CD14+ myelomonocytic cells in initiating MDSCs induction, prompting a tolerogenic immune response to ensure a successful pregnancy.展开更多
In order to promote the winter wheat yield and guarantee seeding quality in double-cropping system,no-tillage or reduced tillage planting modes with different row spacing have been implemented to result in different l...In order to promote the winter wheat yield and guarantee seeding quality in double-cropping system,no-tillage or reduced tillage planting modes with different row spacing have been implemented to result in different levels of yield.A three-year(2012-2015)field experiment was conducted on the experimental farm at Zhuozhou of Hebei Province in North China Plain to compare winter wheat yield from the two planting modes:wide-narrow row space planting mode(WN)and uniform row space planting mode(UR)Both planting modes were performed under reduced tillage conditions with straw mulching.The results showed that in North China Plain WN had positive impacts on crop yield,yield components,leaf area index(LAI)and intercepted photosynthetically active radiation(IPAR)index.Comparing with the UR,IPAR and LAI index for WN were enhanced by 4.8%and 5.2%,respectively.The average yield for WN was 7.2%,significantly greater than that of UR under the same quantity and density.In addition,for WN mode,machinery could pass through with less blocking under large amount of straw mulching,which largely improved tillage efficiency and potentially popularized the conservation tillage technology in North China plain.It is therefore recommended that wide-narrow row space planting mode(WN)combined with reduced tillage and straw mulching be more suitable for conservation tillage in double-cropping pattern areas in North China Plain.展开更多
The commonly used subsoiling cum rotary tiller machine(SRT)in Northern China is a combination of subsoiler and horizontal rotary tiller,however backfilling of the subsoiling slot,excessive vibration and plant residue ...The commonly used subsoiling cum rotary tiller machine(SRT)in Northern China is a combination of subsoiler and horizontal rotary tiller,however backfilling of the subsoiling slot,excessive vibration and plant residue wrapping on rotary components has been rarely considered.Therefore,the rotary components and assembly were redesigned to address these issues and to an SRT fitted with IT225 short curve rotary blades behind the V-shape subsoiling slots and IIT245 long curve rotary blades between the tines.Long and short blades were fitted on a rotor in a double helix,with optimal spiral angles of 65° and 90°,and phase angle of 147°and 180°,respectively.Compared with the commonly used SRT(CSRT),the additional anti-wrapping cutting blades in the circumferential and axial direction of ASRT could remove hanging residue on the blade holders,wrapping on the rotor and formation of an isolation layer.Moreover,the cutting edge curve of anti-wrapping cutting blades was an exponential curve.Field tests demonstrated that the redesigned SRT with anti-vibrating and anti-wrapping rotary components(ASRT)had was a significant advancement over the CSRT.Moreover,the working depth of rotary tillage was more stable,while other observations confirmed that backfilling of the subsoiling slot was also improved.展开更多
In order to solve the serious problems of soil adhesion and blockage as well as high operating resistance for wheat seeders under the condition of sticky heavy loam clay in rice-wheat rotation area,a new concept of no...In order to solve the serious problems of soil adhesion and blockage as well as high operating resistance for wheat seeders under the condition of sticky heavy loam clay in rice-wheat rotation area,a new concept of non-contact pneumatic seeding technology that could rip wheat seed into the soil by high pressure accelerating airflow was proposed in this paper.A preliminary bench experiment was conducted and high-speed photography technology was used to study the parameters of wheat pneumatic seeding under five levels(30%,35%,40%,45%and 50%)of soil moisture content for loam clay.Experimental results showed that:wheat seeds could be ripped into soil without damage and acquired varying degrees of germination by way of pneumatic seeding;shooting depth shown a deepening tendency with the increase in shooting velocity,and the value of seeding depth and seeding velocity are closely related to the soil moisture level,which wheat seeds can achieve higher shooting depth with relative lower shooting velocity when the soil moisture content increases continuously;none of wheat seeds could be ripped into the soil with about 2.93 m/s shooting velocity that accelerated in the form of free fall,while the shooting velocity that wheat seeds needed in order to be completely ripped into soil with 3 mm shooting depth were 40-50 m/s(30%soil moisture content),30-40 m/s(35%soil moisture content),20-30 m/s(40%soil moisture content),10-20 m/s(45%soil moisture content)and 2.93-10 m/s(20%soil moisture content),respectively.The experimental results can provide basic data and technical support for the development of non-contact wheat seeding equipment in rice-wheat rotation area.展开更多
During the last few years,the expression patterns and roles of response gene to complement 32(RGC-32)in various cells and diseases have been hot topics.1 RGC-32 can act as a cell cycle regulator and is involved not on...During the last few years,the expression patterns and roles of response gene to complement 32(RGC-32)in various cells and diseases have been hot topics.1 RGC-32 can act as a cell cycle regulator and is involved not only in cell proliferation2 but also in cell differentiation.RGC-32 was found to be essential for TGF-β-induced vascular smooth muscle cell differentiation from neural crest cells.3 The RGC-32 expression levels were significantly higher in unstimulated peripheral CD14+cells from hyper-immunoglobulin E syndrome patients compared with those from healthy controls.4 Moreover,RGC-32 was identified to be co-localized with CD68+cells in multiple sclerosis plaques.5 The above studies and importance of monocytes/macrophages in immune regulation drove us to explore the expression and function of RGC-32 in monocytes/macrophages.展开更多
No-till planting method is widely used for maize-wheat two-crops-a-year area in the North China Plain.However,cruel soil conditions,especially the large number of maize stalks which are hard to cutoff covering,often c...No-till planting method is widely used for maize-wheat two-crops-a-year area in the North China Plain.However,cruel soil conditions,especially the large number of maize stalks which are hard to cutoff covering,often cause an unsatisfying planting quality.Based on the authors’previous investigation,ultrahigh-pressure(UHP)waterjet is capable to solve this problem and obtain qualified seedbeds.Thus,a UHP waterjet assisted furrow opener for no-till seeder was designed.Field tests showed that double-disc furrow openers worked well with UHP waterjet,since the sharpened disc blades could help to cut soil and residue,meanwhile,minimize soil disturbance.Response surface method(RSM)was used to investigate the relationship among forward speed,waterjet pressure,jet impingement angle and anti-blocking performance(stalks cutoff ratio and depth of soil cutting),and a Box-Behnken three-factor design was used to identify the optional operation parameters.A total of 17 combinations were conducted,and the results showed all three operation parameters significantly affected anti-blocking performance.Stalks cutoff ratio and depth of soil cutting increased with the increase of waterjet pressure,jet impingement angle,and decreased with the increase of forward speed.The optimization analysis indicated that when waterjet pressure was 267-280 MPa,jet impingement angle was 80.2°to 90.0°and forward speed was 4.00-4.42 km/h,the overall performance of UHP waterjet assisted double-disc furrow opener for no-till seeder was maximized.Stalks cutoff ratio could be above 95%and no blockage occurred.This study may provide a new approach and reference for the anti-blocking technology of no-tillage seeding.展开更多
Large amounts of crop stalks left in the field as a result of conservation agriculture cause blockage during no-till planting.To solve this issue,pure waterjet was used to cut off the maize stalks so that the rear fur...Large amounts of crop stalks left in the field as a result of conservation agriculture cause blockage during no-till planting.To solve this issue,pure waterjet was used to cut off the maize stalks so that the rear furrow opener could pass through without blockage.In this investigation,an experimental study on depth of cut,which was the main performance indicator of pure waterjet on cutting maize stalks,was presented.A full factorial design with 200 tests was implemented with respect to three operation parameters,that is traverse speed,waterjet pressure,and standoff distance were considered as variables.An analysis of variance(ANOVA)was carried out in order to determine the statistical significance of individual operation parameters.Using multilinear stepwise regression analysis,a model to predict the cut of depth from the predicted pure waterjet operation to cut maize stalks was then developed.All three operation parameters significantly influenced the cutting performance.Moreover,the results indicated that depth of cut increased with the increase of waterjet pressure,the decrease of traverse speed,and decrease in standoff distance.Waterjet pressure provided major contribution to depth of cut,followed by traverse speed,then standoff distance,which was demonstrated by both ANOVA and regression analysis.The experimental results showed that when the standoff distance was closer than 10 mm and waterjet pressure was 280 MPa,all maize stalks specimen could be cutoff thoroughly.With the consideration of field operating conditions,waterjet pressure of 280 MPa or higher and 10 mm to 15 mm standoff distance were recommended for maize stalks cutting.This analysis provided a realistic approach for the optimization of the ultra-high pressure pure waterjet parameters in maize stalks cutting,which could be used to relieve the occurrence of straw blockage in no-till planting.展开更多
In order to solve the serious problems of seeds are covered by residual film and overhead by straw during no-till seeding,a seed furrow cleaning device for no-till maize seeding was developed,which adopted a collabora...In order to solve the serious problems of seeds are covered by residual film and overhead by straw during no-till seeding,a seed furrow cleaning device for no-till maize seeding was developed,which adopted a collaborative cleaning method of rotating spring teeth and curved sliding shovel.The movement process and motion trajectory of throwing residual film and straw were constructed.The maximum distance of throwing to one side in horizontal and maximum height in vertical were obtained.The motion trajectory of adjacent spring teeth was analyzed by Matlab,the motion trajectories of adjacent spring teeth at different speeds of 120 r/min,150 r/min and 180 r/min were achieved,the theoretical analysis results showed that the area of omitted area decreased with the increase of rotation speed.Based on theoretical and simulation analysis of critical parameters,the forward speed of machine,rotation speed of spring teeth,and dip angle between spring teeth and rotary disc were selected as the influencing factor.Straw cleaning rate(SCR)and residual film cleaning rate(RFCR)were selected as the response values for three factors and three levels of orthogonal experiment design.The optimal combination of the selected parameters was obtained,and the field test verification was also conducted.The results showed that the rotation speed of spring teeth,forward speed and dip angle of spring teeth significantly affect SCR and RFCR were in decreasing order.The field test results indicated that when forward speed was 6 km/h,rotation speed of spring teeth was 180 r/min and dip angle of spring teeth was 40°,SCR and RFCR were 88.27%and 84.31%,respectively.This study provides a reference for the development of no-till seeder in Xinjiang and the northwestern regions of China.展开更多
Plot drill has a significant impact on field breeding by replacing manual seeding.However,the seeding performance of plot drill needs to be further improved as the mechanical transmission method cannot work under the ...Plot drill has a significant impact on field breeding by replacing manual seeding.However,the seeding performance of plot drill needs to be further improved as the mechanical transmission method cannot work under the optimal combination of operating parameters.In this study,a cone compartment tray of sowing device was evaluated under the laboratory conditions,using a self-designed seeding control system to adjust the operating parameters.Among them,a plot seeding control system was involved that could set operating parameters through an Android terminal,which effectively reduced the difficulty of parameters adjustment.The method of central composite experiment design was employed to conduct experiments and explore the effects of experiment factors such as lifting height of storage tube(LHST),rotation speed of cone compartment tray(RSCCT),and rotation speed seed distributor(RSSD)on the seeding uniformity coefficient of variation among rows(SUCVR)and the rate of damaged seeds(RDS).For SUCVR of wheat,the results showed that the importance order of main factors from high to low was RSSD,RSCCT and LHST.And for SUCVR of buckwheat,RSCCT had the largest influence,followed by RSSD,and LHST had the smallest influence.For RDS of wheat and buckwheat,only RSSD had a very significant effect among the main factors.The experiments data of wheat indicated that when operated at 27.2 mm for LHST,4.5 r/min for RSCCT and 1169 r/min for RSSD,the sowing performance of wheat was optimal,with SUCVR and RDS values of 5.02%and 0.117%,respectively.The buckwheat seeding performance was found to be optimal when the LHST,RSCCT and RSSD were 26.5 mm,3.9 r/min and 711 r/min,and SUCVR and RDS were 4.74%and 0.113%.The seeding control system realized the electromechanical control of the seeding equipment,was convenient for parameter setting and stepless adjustment,and could be operated under an optimized combination of operating parameters.The research results could provide a reference for the performance improvement and application of plot drill.展开更多
The optimization-based design of solvent mixtures used for phenolic wastewater treatment was investigated in this work.A nonlinear programming(NLP)model was formulated based on the concepts of computer-aid molecule de...The optimization-based design of solvent mixtures used for phenolic wastewater treatment was investigated in this work.A nonlinear programming(NLP)model was formulated based on the concepts of computer-aid molecule design(Computer-Aided Molecular Design,CAMD)to select solvent mixtures with the best extraction performance considering the constraints of extraction process and the environmental impact.Due to the complexity of the NLP model,multi-start method was adopted to solve this problem in order to get near global optimal solution.The results of the calculations suggested that the optimal mixture consisted of 70.1%n-octanol and 29.9%2-octanone(molar fraction).The 119 sets of experimental results showed that the extraction ability of the optimal solvent mixture identified by CAMD technique was among the top 6 sets compared to the experiment results.The results suggested that the developed NLP model could be able to screen the optimal solvent mixture in phenolic wastewater treatment.展开更多
基金supported by the National Natural Science Foundation of China(32302509)the Weifang University Doctoral Research Launch Fund,China(2022BS18)the National Natural Science Foundation of China(32072518)。
文摘Bud dormancy is a complex physiological process of perennial woody plants living in temperate regions,and it can be affected by various phytohormones.Cytokinin oxidase/dehydrogenases(CKXs)are a group of enzymes essential for maintaining cytokinin homeostasis,yet a comprehensive analysis of these enzymes in peach remains lacking.Here,a total of 51 CKX members from different species,including six from peach,eleven from apple,nine from poplar,seven from Arabidopsis,eight from strawberry,and ten from rice,were identified using the Simple HMM Search tool of TBtools and a BLASTP program and classified into four groups using phylogenetic analysis.Conserved motif and gene structure analysis of these 51 CKX members showed that 10 conserved motifs were identified,and each CKX gene contained at least two introns.Cis-element analysis of PpCKXs showed that all PpCKX genes have light-responsive elements and at least one hormone-responsive element.The changed relative expression levels of six PpCKX genes in peach buds from endodormancy to bud-break were observed by qRT-PCR.Among them,the expression trend of PpCKX6 was almost opposite that of PpEBB1,a positive bud-break regulator in woody plants,around the bud-break stage.Y1H,EMSA,and dual-luciferase assays indicated that PpEBB1negatively regulated PpCKX6 through direct binding to a GCC box-like element located in the promoter region of PpCKX6.In addition,a transient assay showed that overexpression of PpCKX6 delayed the bud-break of peach.These results indicate that the PpCKX genes play an essential role in the dormancy-regrowth process,and Pp CKX6may act downstream of PpEBB1 directly to regulate the bud-break process,which further improves the hormoneregulatory network of dormancy-regrowth of woody plants,and provides new insights for molecular breeding and genetic engineering of peach.
基金supported by the National Natural Science Foundation of China[grant numbers 21873057,22373059]the Natural Science Foundation of Shandong Province[grant numbers ZR2023MB082]。
文摘Despite standard treatment for non-small cell lung cancer(NSCLC)being surgical resection,cancer recurrence and complications,such as induction of malignant pleural effusion(MPE)and significant postoperative pain,usually result in treatment failure.In this study,an alginate-based hybrid hydrogel(SOG)is developed that can be injected into the resection surface of the lungs during surgery.Briefly,endoplasmic reticulum-modified liposomes(MSLs)pre-loaded with the signal transducer and activator of transcription 3(STAT3)small interfering RNA and lidocaine hydrochloride are encapsulated in SOG.Once applied,MSLs strongly downregulated STAT3 expression in the tumor microenvironment,resulting in the apoptosis of lung cancer cells and polarization of tumor-associated macrophages towards the M1-like phenotype.Meanwhile,the release of lidocaine hydrochloride(LID)was beneficial for pain relief and natural killer cell activation.Our data demonstrated MSL@LID@SOG not only efficiently inhibited tumor growth but also potently improved the quality of life,including reduced MPE volume and pain relief in orthotopic NSCLC mouse models,even with a single administration.MSL@LID@SOG shows potential for comprehensive clinical management upon tumor resection in NSCLC,and may alter the treatment paradigms for other cancers.
基金support by Ningbo S&T Innovation 2025 Major Special Program,Ningbo,China,and Zhejiang Provincial Engineering Research Center of Energy Optoelectronic Materials and Devices,Ningbo Institute of Materials Technology&Engineering,Chinese Academy of Sciencessupport by State Key Lab of Luminescent Materials and Devices,South China University of Technology(Skllmd-2022-03).
文摘With rapid progress,organic solar cells(OSCs)are getting closer to the target of real application.However,the stability issue is still one of the biggest challenges that have to be resolved.Especially,the thermal stability of OSCs is far from meeting the requirements of the application.Here,based on the layer-by-layer(LBL)process and by utilizing the dissolubility nature of solvent and materials,binary inverted OSCs(ITO/AZO/PM6/BTP-eC9/MoO3/Ag)with comb shape active morphology are fabricated.High efficiency of 17.13%and simultaneous superior thermal stability(with 93%of initial efficiency retained in~9:00 h under 85℃in N_(2))are demonstrated,showing superior stability to reference cells.The enhancements are attributed to the formed optimal comb shape of the active layer,which could provide a larger D/A interface,thus more charge carriers,render the active blend a more stable morphology,and protect the electrode by impeding ion's migration and corrosion.To the best of our knowledge,this is the best thermal stability of binary OSCs reported in the literature,especially when considering the high efficiency of over 17%.
基金supported by the National Natural Science Foundation of China(Nos.22071221,12374032,and U22A20107)the Natural Science Foundation of Henan Province(No.222301420040)+5 种基金China Postdoctoral Science Foundation(No.2023M743152)the State Key Laboratory of Refractories and Metallurgy(Wuhan University of Science and Technology)(No.G202306)“Grassland Talents”of Inner Mongolia Autonomous Region,Young Talents of Science and Technology in Universities of Inner Mongolia Autonomous Region(No.NJYT23030)“Steed plan High level Talents”of Inner Mongolia University,Carbon neutralization research project(No.STZX202218)Inner Mongolia Autonomous Region Natural Science Foundation(No.2023MS02002)the National Key R&D Program of China(No.2022YFA1205201).
文摘Due to the high structural flexibility and controllable thermal expansion,cubic double ReO_(3)-type negative thermal expansion(NTE)fluorides provide a solution for solving the prominent phenomenon of thermal expansion mismatch between materials.However,the expensive raw materials and complex synthesis steps limit its practical application.In this work,we have designed a more advantageous method for the synthesis of NTE material CaZrF_(6),and it is expected to be generalized to the synthesis of other double ReO_(3)-fluorides.Intriguingly,a new orthorhombic phase CaZrF_(6) has been synthesized via this method in a lower temperature.Unlike the strong isotropic NTE of the cubic phase CaZrF_(6),the orthorhombic phase shows the strong anisotropic positive thermal expansion(PTE).The combined analysis of temperature-dependent X-ray diffraction(XRD),Raman spectra,and first-principles calculations shows that the low frequency phonon vibration mode with negative Grüneisen parameter in cubic CaZrF_(6) are strongly correlated with the transverse thermal vibration of F atoms and dominates the NTE of the material.
基金the National Natural Science Foundation of China(Grant No.52175260)the China Agriculture Research System(Grant No.CARS-03)+3 种基金the Key Research and development plan of Hainan Province(Grant No.ZDYF2022XDNY184)Project of Scientific Research in Colleges and Universities of Hainan Province(Grant No.Hnky2022-93)Research Start-up Fund Project of Hainan University(Grant No.KYQD(ZR)-22036)the authors wish to thank them for their generous financial assistance.
文摘For the problem that when wheat is sucked up by the air suction method,the seeds are aligned in a small area,making it difficult for the contact seed cleaning mechanism to clean the seeds.The mechanism of seed cleaning airflow on wheat seed was studied,the flow velocity distribution relationship of the jet section was defined,the mathematical model of the jet velocity of circular and plane sections was established,and the key factors that could have a significant influence on seed cleaning effect were explored.A non-contact positive pressure air flow seed cleaning method was proposed.After theoretical calculations,it is concluded that the core section lengths of the circular section jet and the inline jet are 24.8 mm and 28.8 mm,respectively.The clearing distance is set to 20 mm.Through the single-factor test,the best air tube nozzle shape was clarified as a vertical inline nozzle.The angle of seed cleaning,the air velocity of seed cleaning,and the negative supply pressure were selected as influencing factors,and the seed leakage index,seed reabsorption index,and seed qualification index as the evaluation indicators to conduct a 3-factor 5-horizontal rotation test.A mathematical regression model of influencing factors and evaluation indexes was established to analyze the influence of these factors and indexes.The optimal operation parameters were obtained as the seed cleaning Angle of 19°,the seed cleaning air velocity of 58 m/s,and the negative pressure of 8.5 kPa.Under the optimal parameters,the seed leakage suction index is 8.23%,the seed reabsorption index is 0.33%,and the seed qualification index is 91.44%,which meets the design requirements.
基金This work was supported by the National Natural Science Foundation of China(Grant No.52175260)Gratitude should be expressed to all the members of the Conservation Tillage Research Centre.
文摘An adequate and uniform press wheel pressure is crucial for the homogeneous development of a crop,as it affects actual seeding depth and germination rate.The problems of uneven compaction of seed furrow and consistency of seeding depth can be caused by the pressure fluctuation of the coil-spring pressure control device(CPCD)when the no-till planter is working on the unplowed ground.In this study,a pneumatic pressure control device(PPCD)was designed for the no-till planter,the key structural parameters of air spring for press wheel pressure(PWP)stability were determined by theoretical analysis and parameter calculation.Using the gas-structure coupling finite element simulation method(FESM),the piston radius,piston angle,and cord angle of the air spring are selected as the test factors,and the vertical stiffness was used as the test index to carry out the quadratic rotation orthogonal combination test to establish the regression model of test index and factor.The bench test of the PPCD was carried out under the optimal parameter combination,piston radius of 27.2 mm,piston angle of 11.7°,and cord angle of 30.0°.The vertical stiffness verification test showed that the simulation test was consistent with the bench test result,the vertical stiffness simulation error was 7.1%,and the internal air pressure simulation error was 3.0%;The control response test showed that the average response time of the air spring inflating and deflating was 0.80 s,the maximum overshoot was 4.33%during inflation,and no pressure overshoot during deflation;Under the condition of-40-40 mm surface relief height,the PPCD could effectively reduce the pressure fluctuation compared with the CPCD,and the average reduction of the pressure fluctuation was about 25.1%.
基金support from the China Scholarship Council(CSC201807040049)from DTU Energy.The authors would like to thank H.Henriksen for his help with cell testing.
文摘Protonic ceramic electrolysis cell(PCEC)is a promising technology for production of pure dry hydrogen due to the low operating temperature and high efficiency.One of the obstacles for commercialization of PCEC technology is the poor performance and insufficient long-term durability of the oxygen electrode.In this study,we address the above challenge by designing a LaCoO_(3)(LC)catalyst infiltrated porous BaZr_(0.8)Y_(0.2)O_(3)−δ(BZY20)backbone electrode(LC-BZY20).The performance and durability of the LC-BZY20 electrode are investigated on symmetrical cells using electrochemical impedance spectroscopy(EIS).The total electrode polarization resistance(RP)values of the electrode are 0.56,1.24,2.18,and 2.90Ωcm2 in 3vol%humidified synthetic air at 600,550,500,and 450℃,respectively,indicating good electrochemical performance of the LC-BZY20 electrode.Furthermore,the LC-BZY20 electrode displays good stability,without significant performance degradation when tested at 600℃ in 10vol%humidified air for 900h.We further study the influence of oxygen partial pressure(PO_(2))and steam partial pressure(P_(H_(2)O))on the response of the EIS data,and propose a set of chemical and electrochemical processes involved in the steam splitting reaction in the LC-BZY20 electrode.
基金This work was supported by the National Nature Science Foundation of China (Nos. 31270971, 81072406 and 31100650), the China PostdoctoralScience Foundation (Nos. 2013M541922) and the Independent Innovation Foundation of Shandong University (No. 2012TS143). We would like to thank Professor Jian Li (Beth Israel Deaconess Medical Center, Harvard Medical School) for providing the RGC-32 overexpression vector and the RGC-32 antibody.
文摘Response gene to complement 32 (RGC-32) is a cell cycle regulator involved in the proliferation, differentiation and migration of cells and has also been implicated in angiogenesis. Here we show that RGC-32 expression in macrophages is induced by IL-4 and reduced by LPS, indicating a link between RGC-32 expression and M2 polarization. We demonstrated that the increased expression of RGC-32 is characteristic of alternatively activated macrophages, in which this protein suppresses the production of pro-inflammatory cytokine IL-6 and promotes the production of the anti-inflammatory mediator TGF-β. Consistent with in vitro data, tumor-associated macrophages (TAMs) express high levels of RGC-32, and this expression is induced by tumor-derived ascitic fluid in an M-CSF- and/or IL-4-dependent manner. Collectively, these results establish RGC-32 as a marker for M2 macrophage polarization and indicate that this protein is a potential target for cancer immunotherapy, targeting tumor-associated macrophages.
基金This research was financially supported by the Special Fund of Ministry of Agriculture of China for Public Welfare Projects(No.201503136)Natural Science Fund Project in Anhui Province(No.1708085ME135)Natural Science Major Project in Anhui Province(No.KJ2018ZD016).
文摘In view of the difficulties in weeding and plant protection in the middle and late period of maize planting,this paper proposed a self-propelled thermal fogger chassis.According to the theoretical calculation and agronomic requirements for maize planting,the structure and working principles of the self-propelled thermal fogger chassis were introduced.On this basis,the multi-body dynamics model of chassis structure was established,and the chassis traction,steering and obstacle surmounting performances were also analyzed.Then the rationality and the feasibility of the design were verified through the furrow running test and test equipped with thermal fogger.Test results showed that,the traction performance improves with the decrease of soil deformation index and increase of cohesion,and when track pre-tensioning force was about 1000 N,the machine had a good traction performance;with the decrease of the soil deformation index and the increase of cohesive force,the stability of the single side brake turn of the chassis becomes better;on the contrary,with the increase of the tightness of the crawler,the steering radius turns smaller and the steering stability becomes worse.Under heavy clay,with the pre-tensioning of 1000 N,the machine has better steering stability and smaller turning radius.The obstacle-surmounting simulation result shows that on sandy soil road,the maximum climbing angle for the chassis is 42°,the height of vertical obstacle crossing is 170 mm and the trench width is 440 mm.The study provides a reference for the design of plant protection machinery in the middle and late stages of maize planting.
文摘Successful human pregnancy requires the maternal immune system to recognize and tolerate the semi-allogeneic fetus. Myeloid-derived suppressor cells (MDSCs), which are capable of inhibiting T-cell responses, are highly increased in the early stages of pregnancy. Although recent reports indicate a role for MDSCs in fetal-maternal tolerance, little is known about the expansion of MDSCs during pregnancy. In the present study, we demonstrated that the trophoblast cell line HTR8/SVneo could instruct peripheral CD14+ myelomonocytic cells toward a novel subpopulation of MDSCs, denoted as CD 14 + H LA-DR-/=~w cells, with suppressive activity and increased expression of I DO 1, ARG- 1, a nd COX2. After interaction with HTR8/SVneo cells, CD14+ myelomonocytic cells secrete high levels of CCL2, promoting the expression of signal transducer and activator of transcription 3. We utilized a neutralizing monoclonal antibody to reveal the prominent role of CCL2 in the induction of CD14+HLA-DR-/low MDSCs. In combination, the results of the present study support a novel role for the cross-talk between the trophoblast cell line HTR8/SVneo and maternal CD14+ myelomonocytic cells in initiating MDSCs induction, prompting a tolerogenic immune response to ensure a successful pregnancy.
基金This study was financially supported by the Special Fund for Agro-scientific Research in the Public Interest from the Ministry of Agriculture,China(Grant No.201503136)Modern Agricultural Industry Technology System(Grant No.CARS-03)the Program for Changjiang Scholars and Innovative Research Team in University of China(Grant No.IRT13039).
文摘In order to promote the winter wheat yield and guarantee seeding quality in double-cropping system,no-tillage or reduced tillage planting modes with different row spacing have been implemented to result in different levels of yield.A three-year(2012-2015)field experiment was conducted on the experimental farm at Zhuozhou of Hebei Province in North China Plain to compare winter wheat yield from the two planting modes:wide-narrow row space planting mode(WN)and uniform row space planting mode(UR)Both planting modes were performed under reduced tillage conditions with straw mulching.The results showed that in North China Plain WN had positive impacts on crop yield,yield components,leaf area index(LAI)and intercepted photosynthetically active radiation(IPAR)index.Comparing with the UR,IPAR and LAI index for WN were enhanced by 4.8%and 5.2%,respectively.The average yield for WN was 7.2%,significantly greater than that of UR under the same quantity and density.In addition,for WN mode,machinery could pass through with less blocking under large amount of straw mulching,which largely improved tillage efficiency and potentially popularized the conservation tillage technology in North China plain.It is therefore recommended that wide-narrow row space planting mode(WN)combined with reduced tillage and straw mulching be more suitable for conservation tillage in double-cropping pattern areas in North China Plain.
基金The authors gratefully acknowledge that this research was financially supported by the Modern Agricultural Industry Technology System(Grant No.CARS-03)Special Fund for Agro-scientific Research in the Public Interest from the Ministry of Agriculture,China(Grant No.201503136)Innovative Research Team in University of China(Grant No.IRT13039).
文摘The commonly used subsoiling cum rotary tiller machine(SRT)in Northern China is a combination of subsoiler and horizontal rotary tiller,however backfilling of the subsoiling slot,excessive vibration and plant residue wrapping on rotary components has been rarely considered.Therefore,the rotary components and assembly were redesigned to address these issues and to an SRT fitted with IT225 short curve rotary blades behind the V-shape subsoiling slots and IIT245 long curve rotary blades between the tines.Long and short blades were fitted on a rotor in a double helix,with optimal spiral angles of 65° and 90°,and phase angle of 147°and 180°,respectively.Compared with the commonly used SRT(CSRT),the additional anti-wrapping cutting blades in the circumferential and axial direction of ASRT could remove hanging residue on the blade holders,wrapping on the rotor and formation of an isolation layer.Moreover,the cutting edge curve of anti-wrapping cutting blades was an exponential curve.Field tests demonstrated that the redesigned SRT with anti-vibrating and anti-wrapping rotary components(ASRT)had was a significant advancement over the CSRT.Moreover,the working depth of rotary tillage was more stable,while other observations confirmed that backfilling of the subsoiling slot was also improved.
基金This paper was funded by the Program for China Agriculture Research System(CARS-03)and Changjiang Scholars,Innovative Research Team in University of China(Grant No.IRT13039).Gratitude should be expressed to all the members of Conservation Tillage Research Centre.
文摘In order to solve the serious problems of soil adhesion and blockage as well as high operating resistance for wheat seeders under the condition of sticky heavy loam clay in rice-wheat rotation area,a new concept of non-contact pneumatic seeding technology that could rip wheat seed into the soil by high pressure accelerating airflow was proposed in this paper.A preliminary bench experiment was conducted and high-speed photography technology was used to study the parameters of wheat pneumatic seeding under five levels(30%,35%,40%,45%and 50%)of soil moisture content for loam clay.Experimental results showed that:wheat seeds could be ripped into soil without damage and acquired varying degrees of germination by way of pneumatic seeding;shooting depth shown a deepening tendency with the increase in shooting velocity,and the value of seeding depth and seeding velocity are closely related to the soil moisture level,which wheat seeds can achieve higher shooting depth with relative lower shooting velocity when the soil moisture content increases continuously;none of wheat seeds could be ripped into the soil with about 2.93 m/s shooting velocity that accelerated in the form of free fall,while the shooting velocity that wheat seeds needed in order to be completely ripped into soil with 3 mm shooting depth were 40-50 m/s(30%soil moisture content),30-40 m/s(35%soil moisture content),20-30 m/s(40%soil moisture content),10-20 m/s(45%soil moisture content)and 2.93-10 m/s(20%soil moisture content),respectively.The experimental results can provide basic data and technical support for the development of non-contact wheat seeding equipment in rice-wheat rotation area.
基金supported by the National Nature Science Foundation of China(No.31470885)the Natural Science Foundation of Shandong Province(No.ZR2016HM02).
文摘During the last few years,the expression patterns and roles of response gene to complement 32(RGC-32)in various cells and diseases have been hot topics.1 RGC-32 can act as a cell cycle regulator and is involved not only in cell proliferation2 but also in cell differentiation.RGC-32 was found to be essential for TGF-β-induced vascular smooth muscle cell differentiation from neural crest cells.3 The RGC-32 expression levels were significantly higher in unstimulated peripheral CD14+cells from hyper-immunoglobulin E syndrome patients compared with those from healthy controls.4 Moreover,RGC-32 was identified to be co-localized with CD68+cells in multiple sclerosis plaques.5 The above studies and importance of monocytes/macrophages in immune regulation drove us to explore the expression and function of RGC-32 in monocytes/macrophages.
基金This study was financially supported by the Special Fund for Agro-scientific Research in the Public Interest from the Ministry of Agriculture,China(Grant No.201503136).
文摘No-till planting method is widely used for maize-wheat two-crops-a-year area in the North China Plain.However,cruel soil conditions,especially the large number of maize stalks which are hard to cutoff covering,often cause an unsatisfying planting quality.Based on the authors’previous investigation,ultrahigh-pressure(UHP)waterjet is capable to solve this problem and obtain qualified seedbeds.Thus,a UHP waterjet assisted furrow opener for no-till seeder was designed.Field tests showed that double-disc furrow openers worked well with UHP waterjet,since the sharpened disc blades could help to cut soil and residue,meanwhile,minimize soil disturbance.Response surface method(RSM)was used to investigate the relationship among forward speed,waterjet pressure,jet impingement angle and anti-blocking performance(stalks cutoff ratio and depth of soil cutting),and a Box-Behnken three-factor design was used to identify the optional operation parameters.A total of 17 combinations were conducted,and the results showed all three operation parameters significantly affected anti-blocking performance.Stalks cutoff ratio and depth of soil cutting increased with the increase of waterjet pressure,jet impingement angle,and decreased with the increase of forward speed.The optimization analysis indicated that when waterjet pressure was 267-280 MPa,jet impingement angle was 80.2°to 90.0°and forward speed was 4.00-4.42 km/h,the overall performance of UHP waterjet assisted double-disc furrow opener for no-till seeder was maximized.Stalks cutoff ratio could be above 95%and no blockage occurred.This study may provide a new approach and reference for the anti-blocking technology of no-tillage seeding.
基金supported by the Special Fund for Agro-scientific Research in the Public Interest from the Ministry of Agriculture,China(Grant No.201503136).
文摘Large amounts of crop stalks left in the field as a result of conservation agriculture cause blockage during no-till planting.To solve this issue,pure waterjet was used to cut off the maize stalks so that the rear furrow opener could pass through without blockage.In this investigation,an experimental study on depth of cut,which was the main performance indicator of pure waterjet on cutting maize stalks,was presented.A full factorial design with 200 tests was implemented with respect to three operation parameters,that is traverse speed,waterjet pressure,and standoff distance were considered as variables.An analysis of variance(ANOVA)was carried out in order to determine the statistical significance of individual operation parameters.Using multilinear stepwise regression analysis,a model to predict the cut of depth from the predicted pure waterjet operation to cut maize stalks was then developed.All three operation parameters significantly influenced the cutting performance.Moreover,the results indicated that depth of cut increased with the increase of waterjet pressure,the decrease of traverse speed,and decrease in standoff distance.Waterjet pressure provided major contribution to depth of cut,followed by traverse speed,then standoff distance,which was demonstrated by both ANOVA and regression analysis.The experimental results showed that when the standoff distance was closer than 10 mm and waterjet pressure was 280 MPa,all maize stalks specimen could be cutoff thoroughly.With the consideration of field operating conditions,waterjet pressure of 280 MPa or higher and 10 mm to 15 mm standoff distance were recommended for maize stalks cutting.This analysis provided a realistic approach for the optimization of the ultra-high pressure pure waterjet parameters in maize stalks cutting,which could be used to relieve the occurrence of straw blockage in no-till planting.
基金This work was supported by the National Natural Science Foundation of China(Grant No.52165039)Xinjiang Agricultural Machinery R&D,Manufacturing,Promotion,and Application Integration Project(Grant No.YTHSD2022-14)+1 种基金China Agriculture Research System of MOF and MARA(Grant No.CARS-03)Xinjiang Key Laboratory of Intelligent Agricultural Equipment.Gratitude should be expressed to all the members of Conservation Tillage Research Centre.
文摘In order to solve the serious problems of seeds are covered by residual film and overhead by straw during no-till seeding,a seed furrow cleaning device for no-till maize seeding was developed,which adopted a collaborative cleaning method of rotating spring teeth and curved sliding shovel.The movement process and motion trajectory of throwing residual film and straw were constructed.The maximum distance of throwing to one side in horizontal and maximum height in vertical were obtained.The motion trajectory of adjacent spring teeth was analyzed by Matlab,the motion trajectories of adjacent spring teeth at different speeds of 120 r/min,150 r/min and 180 r/min were achieved,the theoretical analysis results showed that the area of omitted area decreased with the increase of rotation speed.Based on theoretical and simulation analysis of critical parameters,the forward speed of machine,rotation speed of spring teeth,and dip angle between spring teeth and rotary disc were selected as the influencing factor.Straw cleaning rate(SCR)and residual film cleaning rate(RFCR)were selected as the response values for three factors and three levels of orthogonal experiment design.The optimal combination of the selected parameters was obtained,and the field test verification was also conducted.The results showed that the rotation speed of spring teeth,forward speed and dip angle of spring teeth significantly affect SCR and RFCR were in decreasing order.The field test results indicated that when forward speed was 6 km/h,rotation speed of spring teeth was 180 r/min and dip angle of spring teeth was 40°,SCR and RFCR were 88.27%and 84.31%,respectively.This study provides a reference for the development of no-till seeder in Xinjiang and the northwestern regions of China.
基金This study was supported by the Program for China Agriculture Research System(Grant No.CARS-03)Chinese Universities Scientific Fund(Grant No.2020TC116)+1 种基金Research Innovation Fund for Graduate Students of China Agricultural University(CAU)(Grant No.2020XYZC06A)The authors thank all the members working at the Conservation Tillage Research Centre and for proving their inputs to this paper.
文摘Plot drill has a significant impact on field breeding by replacing manual seeding.However,the seeding performance of plot drill needs to be further improved as the mechanical transmission method cannot work under the optimal combination of operating parameters.In this study,a cone compartment tray of sowing device was evaluated under the laboratory conditions,using a self-designed seeding control system to adjust the operating parameters.Among them,a plot seeding control system was involved that could set operating parameters through an Android terminal,which effectively reduced the difficulty of parameters adjustment.The method of central composite experiment design was employed to conduct experiments and explore the effects of experiment factors such as lifting height of storage tube(LHST),rotation speed of cone compartment tray(RSCCT),and rotation speed seed distributor(RSSD)on the seeding uniformity coefficient of variation among rows(SUCVR)and the rate of damaged seeds(RDS).For SUCVR of wheat,the results showed that the importance order of main factors from high to low was RSSD,RSCCT and LHST.And for SUCVR of buckwheat,RSCCT had the largest influence,followed by RSSD,and LHST had the smallest influence.For RDS of wheat and buckwheat,only RSSD had a very significant effect among the main factors.The experiments data of wheat indicated that when operated at 27.2 mm for LHST,4.5 r/min for RSCCT and 1169 r/min for RSSD,the sowing performance of wheat was optimal,with SUCVR and RDS values of 5.02%and 0.117%,respectively.The buckwheat seeding performance was found to be optimal when the LHST,RSCCT and RSSD were 26.5 mm,3.9 r/min and 711 r/min,and SUCVR and RDS were 4.74%and 0.113%.The seeding control system realized the electromechanical control of the seeding equipment,was convenient for parameter setting and stepless adjustment,and could be operated under an optimized combination of operating parameters.The research results could provide a reference for the performance improvement and application of plot drill.
基金the National Natural Science Foundation(Grant 51178446).
文摘The optimization-based design of solvent mixtures used for phenolic wastewater treatment was investigated in this work.A nonlinear programming(NLP)model was formulated based on the concepts of computer-aid molecule design(Computer-Aided Molecular Design,CAMD)to select solvent mixtures with the best extraction performance considering the constraints of extraction process and the environmental impact.Due to the complexity of the NLP model,multi-start method was adopted to solve this problem in order to get near global optimal solution.The results of the calculations suggested that the optimal mixture consisted of 70.1%n-octanol and 29.9%2-octanone(molar fraction).The 119 sets of experimental results showed that the extraction ability of the optimal solvent mixture identified by CAMD technique was among the top 6 sets compared to the experiment results.The results suggested that the developed NLP model could be able to screen the optimal solvent mixture in phenolic wastewater treatment.