[Objective] This study aimed to investigate the effects of gel-based controlled release fertilizers (CRFs) on agronomic characteristics and physiological indices of corn. [Method] Pot experiment was carried out to i...[Objective] This study aimed to investigate the effects of gel-based controlled release fertilizers (CRFs) on agronomic characteristics and physiological indices of corn. [Method] Pot experiment was carried out to investigate the agronomic characteristics and physiological indices of corn fertilized with controlled release fertilizers compared with conventional fertilizer (CF). [Result] Plant height, stem girth, leaf area and root volume of corn were significantly increased under the CRF treatments; photosynthetic rate and soluble protein content were also improved. Dry matter accumulations under the two CRF treatments were increased by 21.3% and 17.0% compared with CF application at one time (CF1), and 19.6% and 15.4% with CF application at two times (CF2), respectively. Accumulation amounts of N, P and K in whole plant under the two CRF treatments were increased by 44.0% -24.7% , 40.0%-25.9% and 20.1% -13.9% ; and the nutrient use efficiencies of N, P and K were improved by 22.9% -13.4% , 11.2% -9.6% and 17.5% -12.1% , respectively. [Conclusion] The results implied that the CRFs could significantly improve nutrient use efficiency and plant yield.展开更多
Aim In vitro dissolution test and pharmacokinetics in beagle dogs wereconducted to assess the formulation of tretinoin in self-emulsifying systems. Methods Theconcentrations of tretinoin were determined by HPLC. A cro...Aim In vitro dissolution test and pharmacokinetics in beagle dogs wereconducted to assess the formulation of tretinoin in self-emulsifying systems. Methods Theconcentrations of tretinoin were determined by HPLC. A crossover study was performed in four fastingbeagle dogs with the formulation of self-emulsifying systems and commercial capsules. Results Theresults showed that the dissolution rate in 15 min of tretinoin in self-emulsifying systems washigher than 80% while that of the commercial capsules was lower than 5% . The area under the plasmaconcentration-time curve (AUC) of the self-emulsifying formulation was significantly higher andC_(max) was approximately two times greater than those of commercial capsule, respectively, Inaddition, the time taken to reach peak was shorter (2 h to 1.25 h) for self-emulsifying formulationof tretinoin. Conclusion The self-emulsifying drug delivery systems.can significantly increasetretinoin in vitro dissolution and in vivo absorption.展开更多
In the fight against cancer, controlled drug delivery systems have emerged to enhance the therapeutic efficacy and safety of anti-cancer drugs. Among these systems, mesoporous silica nanoparticles (MSNs) with a func...In the fight against cancer, controlled drug delivery systems have emerged to enhance the therapeutic efficacy and safety of anti-cancer drugs. Among these systems, mesoporous silica nanoparticles (MSNs) with a functional surface possess obvious advantages and were thus rapidly developed for cancer treatment. Many stimuli-responsive materials, such as nanopartides, polymers, and inorganic materials, have been applied as caps and gatekeepers to control drug release from MSNs. This review presents an overview of the recent progress in the production of pH-responsive MSNs based on the pH gradient between normal tissues and the tumor microenvironment. Four main categories of gatekeepers can respond to acidic conditions. These categories will be described in detail.展开更多
The auto-gelling and drug release properties of the thermosensitive chitosan-β-glycerophosphate formulation were investigated. According to rheological study, gelation lag time of chitosan/β-glycerophosphate (GP) ...The auto-gelling and drug release properties of the thermosensitive chitosan-β-glycerophosphate formulation were investigated. According to rheological study, gelation lag time of chitosan/β-glycerophosphate (GP) solutions varied from 2 to 60min with different deacetylation degree of chitosan, pH, gelation temperature, and the particles in the sol. The gelation properties were also found to influence the release profilles of a hydrophilic drug, 5-fluorouracil (5-FU). Morphological examination by scanning electron microphotography demonstrated that large "pores" occurred during the gel-forming process, which created hydrophilic environment and led to the rapid initial release of the drug (85% in f'LrSt 8h). Poly-3-hydroxybutyrate (PHB), a biodegradable material, was applied here as scaffold to capture 5-FU into microparticles with high encapsulation efficiency by solvent-nonsolvent method. Combination of these microparticles into the chitosan-β-GP formulation could drop the rapid initial release from 85% down to 29% in the optimized PHB content (75%, by mass). The release could sustain for about 10 months. Tiffs study provided an understanding of the potential of injectable implant using thermosensitive chitosan-β-GP formulation containing PHB based particles for the water soluble drugs that need the property of long-term delivery.展开更多
In order to acquire the flow pattern and investigate the settling behavior of the red mud in the separation thickener,computational fluid dynamics(CFD),custom subroutines and agglomerates settling theory were employed...In order to acquire the flow pattern and investigate the settling behavior of the red mud in the separation thickener,computational fluid dynamics(CFD),custom subroutines and agglomerates settling theory were employed to simulate the three-dimensional flow field in an industrial scale thickener with the introduction of a self-dilute feed system.The simulation results show good agreement with the measurement onsite and the flow patterns of the thickener are presented and discussed on both velocity and concentration field.Optimization experiments on feed well and self-dilute system were also carried out,and indicate that the optimal thickener system can dilute the solid concentration in feed well from 110 g/L to 86 g/L which would help the agglomerates' formation and improve the red mud settling speed.Furthermore,the additional power of recirculation pump can be saved and flocculants dosage was reduced from 105g/t to 85g/t in the operation.展开更多
Halloysite nanotube-composited thermo-responsive hydrogel system has been successfully developed for controlled drug release by copolymerization of N-isopropylacrylamide (NIPAM) with silane-modified halloysite nanot...Halloysite nanotube-composited thermo-responsive hydrogel system has been successfully developed for controlled drug release by copolymerization of N-isopropylacrylamide (NIPAM) with silane-modified halloysite nanotubes (HNT) through thermally initiated free-radical polymerization. With methylene blue as a model drug, thermo-responsive drug release results demonstrate that the drug release from the nanotubes in the composited hy-drogel can^be well controlled by manipulating the environmental temperature. When the hydrogel network is swol- len at temperature below the lower critical solution temperature (LCST), drug releases steadily from lumens of the embedded nanotubes, whereas the drug release stops when hydrogel shrinks at temperature above the LCST. The release of model drug from the HNT-composited hydrogel matches well with its thermo-responsive volume phasetransition, and shows characteristics of well controlled release. The design strategy and release results of the pro- posed novel HNT-composited thermo-responsive hydrogel system provide valuable guidance for designing respon- s_i_ve nanocomposites for controlled-release of active agents.展开更多
According to the mining method for Dongguashan Copper Mine and Tongkeng Mine in China, and with the help of the cavity monitoring system(CMS) and mining software Surpac, the 3D cavity models were established exactly...According to the mining method for Dongguashan Copper Mine and Tongkeng Mine in China, and with the help of the cavity monitoring system(CMS) and mining software Surpac, the 3D cavity models were established exactly. A series of correlative techniques for calculating stope over-excavation and under-excavation, stope dilution and ore loss rates, and the blasting design of the pillar with complicated irregular boundaries were developed. These techniques were applied in Dongguashan Copper Mine and Tongkeng Mine successfully. Using these techniques, the dilution rates of stopes 52-2^#, 52-6^#, 52-8^#and 52-10^# of Dongguashan Copper Mine are calculated to be 2.12%, 8.46%, 12-67% and 10.68%, respectively, and the ore loss rates of stopes 52-6^# and 5-8^# are 4.41% and 3.70%, severally. Furthermore, according to the design accomplished by the technique for a pillar of Tongkeng Mine with irregular boundary, the volume, total length of boreholes and the dynamite quantity of the pillar are computed to be 1.2 ×10^4 m^3, 2.98 km and 10.97 t, correspondingly.展开更多
In order to carry out numerical simulation using geologic structural data obtained from Landmark(seismic interpretation system), underground geological structures are abstracted into mechanical models which can reflec...In order to carry out numerical simulation using geologic structural data obtained from Landmark(seismic interpretation system), underground geological structures are abstracted into mechanical models which can reflect actual situations and facilitate their computation and analyses.Given the importance of model building, further processing methods about traditional seismic interpretation results from Landmark should be studied and the processed result can then be directly used in numerical simulation computations.Through this data conversion procedure, Landmark and FLAC(the international general stress software) are seamlessly connected.Thus, the format conversion between the two systems and the pre-and post-processing in simulation computation is realized.A practical application indicates that this method has many advantages such as simple operation, high accuracy of the element subdivision and high speed, which may definitely satisfy the actual needs of floor grid cutting.展开更多
In the present paper, the author makes some comments on the holistic action of acupuncture from the regulative effect on the nerve-endocrine-immune network, and the close relationship between the nerve-endocrine-immun...In the present paper, the author makes some comments on the holistic action of acupuncture from the regulative effect on the nerve-endocrine-immune network, and the close relationship between the nerve-endocrine-immune network and the meridian-collateral system of TCM. The wholism concept of TCM refers to the organism being an integrated entirety, and the regulatory effect of acupuncture on functional activities of the organism relies on the integral connection of the acupoint-meridian-collateral-zangfu-organ system. When stimulated with acupuncture, the human body will brings its potential force into full play in preventing and treating diseases.展开更多
Objective:This study aimed to lay the foundation for the research on Panax notoginseng saponins(PNS)in pH-sensitive in situ gel and the development and improvement of related preparations.Methods:We used Carbopol■940...Objective:This study aimed to lay the foundation for the research on Panax notoginseng saponins(PNS)in pH-sensitive in situ gel and the development and improvement of related preparations.Methods:We used Carbopol■940,a commonly used pH-sensitive polymer,and the thickener hydroxypropyl methylcellulose(HPMC E4M)as an ophthalmic gel matrix to prepare an ophthalmic in situ gel of PNS.In addition,formula optimization was performed by assessing gelling capability with the results of in vitro release studies.In vitro(corneal permeation,rheological,and stability)and in vivo(ocular irritation and preliminary pharmacokinetics in the vitreous)studies were also performed.Results:The results demonstrated that the in situ gelling systems containing PNS showed a sustained release of the drug,making it an ideal ocular delivery system for improving posterior ocular bioavailability.Conclusions:This study lays the foundation for the research of PNS contained in an in situ pH-triggered gel as well as the development and improvement of related preparations.It concurrently traditional Chinese medicine with a contemporary in situ gelling approach to provide new directions for the treatment of posterior ocular diseases such as diabetic retinopathy.展开更多
A light and temperature dual responsive copolymer,poly(7-(4-vinylbenzy-loxyl)-4-methylcoumarin-co-N vinyl caprolactam-co-tri(ethylene glycol)methyl ether methacrylate)(PVNM),was grafted on the surface of dopamine base...A light and temperature dual responsive copolymer,poly(7-(4-vinylbenzy-loxyl)-4-methylcoumarin-co-N vinyl caprolactam-co-tri(ethylene glycol)methyl ether methacrylate)(PVNM),was grafted on the surface of dopamine based mesoporous silica nanoparticles(MSNs).The resulting polymer brush,MSNs-g-PVNM,was characterized by FT-IR,TEM,TGA and XPS.The dual responsive behaviors of MSNs-g-PVNM were systematically studied.With imidacloprid as the model guest pesticide,the loading percentage and loading efficiency of the polymer brush were determined as 9.2%and 40.6%,respectively.The release efficiency of imidacloprid in MSNs-g-PVNM was the lowest value of 5.4%at 20℃ and 365 nm,and it reached the highest value of 52.4%at 50℃ and 254 nm.The loss percentage of imidacloprid on the leaves contained imidacloprid-loaded MSNs-g-PVNM(8.4%)was much less than that contained only imidacloprid(25.2%)after three rinses.It was confirmed that the release process of imidacloprid was well regulated through changing external conditions such as light and temperature.展开更多
3D seismic prospecting in mining areas of Xieqiao Colliery is a successfulmodel for an advancement from the resource prospecting to mining prospecting stagein coal fields. Its results have proved that faults with a th...3D seismic prospecting in mining areas of Xieqiao Colliery is a successfulmodel for an advancement from the resource prospecting to mining prospecting stagein coal fields. Its results have proved that faults with a throw of 5-10 m can be detected in an area with good seismogeologic conditions by using 3D seismic technique.Detection of underground tunnels for the first time utilizing 3D seismic data indicates that subsided columns, gotten and mine goaf can be detected using 3D seismic technique, so it has a broad applied prospect.展开更多
Objective:The cross-linked production,which was prepared by HA and cross-linking agent STMP,EDC,GP through cross-linking reaction,might be used in drug delivery system(DDS).To ensure the security of clinical applicati...Objective:The cross-linked production,which was prepared by HA and cross-linking agent STMP,EDC,GP through cross-linking reaction,might be used in drug delivery system(DDS).To ensure the security of clinical application,the excellent properties such as none cell toxicity,nonirritant,none general toxicity,none immunological rejection are necessary.Methods:In accordance with the request of GB/T 16886.1 on security evaluation of medical biomaterials,cell toxicity test,hemolysis test,intracutaneous stimulation test,acute toxicity test,and hypersensitive test were required.Results:Cell toxicity of HA-STMP,HA-EDC,HA-GP were all less than 1.All hypersensitive tests were eligible.But HA-EDC,HA-GP produced different degrees of slight thrill,slight toxicity,hemolysis rate,which were larger than the standard value.Conclusion:HA-STMP possesses favourable biocompatibility,which is a kind of ideal biomaterials and drug carriers.展开更多
Chile is a very important country that forms part of the Andean metallogenic belts. The Atacama and Domeyko fault systems in northern Chile control the tectonic- magmatic activities that migrate eastward and the types...Chile is a very important country that forms part of the Andean metallogenic belts. The Atacama and Domeyko fault systems in northern Chile control the tectonic- magmatic activities that migrate eastward and the types of mineral resources. In this paper, we processed and interpreted aeromagnetic data from northern Chile using reduction to pole, upward field continuation, the second derivative calculation in the vertical direction, inclination angle calculation, and analytical signal amplitude analysis. We revealed the locations and planar distribution characteristics of the regional deep faults along the NNE and NS directions. Furthermore, we observed that the major reasons for the formation of the tectonic-magmatic rocks belts were the nearly parallel deep faults distributed from west to east and multiple magmatic activities along these faults. We ascertained the locations of volcanic mechanisms and the relationships between them using these regional deep faults. We deduced the spatial distributions of the basic-intermediate, basic, and acidic igneous rocks, intrusive rocks, and sedimentary sequences. We showed the linear positive magnetic anomalies and magnetic anomaly gradient zones by slowly varying the background, negative magnetic anomaly field, which indicated the presence of strong magmatic activities in these regional deep faults; it also revealed the favorable areas of copper and polymetallic mineralization. This study provides some basic information for further research on the geology, structural characteristics, and mineral resource prospecting in northern Chile.展开更多
In some worldwide hard coal basins recovery of methane from virgin coal beds is difficult. In general,mentioned difficulties are related to geo-mechanical, petrographical and physical-chemical properties of coals in q...In some worldwide hard coal basins recovery of methane from virgin coal beds is difficult. In general,mentioned difficulties are related to geo-mechanical, petrographical and physical-chemical properties of coals in question, occurring for example in the Bowen Basin(Australia) or the Upper Silesian Coal Basin(Poland). Among numerous properties and parameters, the following are very essential: susceptibility of coal beds to deformation connected with coal stress state change and contemporary shrinkage of the coal matrix during methane desorption. Those adverse geo-mechanical and physical-chemical effects are accompanied by essential change of the porous coal structure, which under these disadvantageous conditions is very complex. This study aims to show difficulties, which occur in phase of recognition of the methane-reach coal deposit. Volume absorbed methane(not surface adsorbed) in sub-micropores having minimal size comparable with gas molecule diameter must possess energy allowing separation of the nodes and methane release to micropores.展开更多
The critical properties of the bond-diluted mixed spin-1/2 and spin-1 transverse Ising system with singleion anisotropy are investigated by means of the effective field theory with correlations. Particular emphasis is...The critical properties of the bond-diluted mixed spin-1/2 and spin-1 transverse Ising system with singleion anisotropy are investigated by means of the effective field theory with correlations. Particular emphasis is given to the square lattice for which phase diagrams are obtained. If transverse field varies in the certain ranges we find that the tricritical point is obtained for the value of the bond concentration in a restricted region. We also observe that the reentrant phase transition may occur in the present system if single-ion anisotropy parameter is not large and if transverse field is small. On the other hand, for certain values of the system parameters, new induced magnetic ordering can be obtained. We find a number of interesting phenomena that are not predicted by previous literatures. The influence of the transverse field on the behaviours of the reentrant phase transition and induced magnetic ordering is discussed. A detailed description of the phase transition is presented.展开更多
A new method of system failure analysis was proposed. First, considering the relationships between the failure subsystems,the decision making trial and evaluation laboratory(DEMATEL) method was used to calculate the d...A new method of system failure analysis was proposed. First, considering the relationships between the failure subsystems,the decision making trial and evaluation laboratory(DEMATEL) method was used to calculate the degree of correlation between the failure subsystems, analyze the combined effect of related failures, and obtain the degree of correlation by using the directed graph and matrix operations. Then, the interpretative structural modeling(ISM) method was combined to intuitively show the logical relationship of many failure subsystems and their influences on each other by using multilevel hierarchical structure model and obtaining the critical subsystems. Finally, failure mode effects and criticality analysis(FMECA) was used to perform a qualitative hazard analysis of critical subsystems, determine the critical failure mode, and clarify the direction of reliability improvement.Through an example, the result demonstrates that the proposed method can be efficiently applied to system failure analysis problems.展开更多
We calculate the binding energies of Ni, Cu, Xe, Cs, Pt, Au, Np, Pu isotope chains using two interaction parameter sets NL-3 and NL-Z, and compared the relative errors of the even-even nuclei with those of odd-even nu...We calculate the binding energies of Ni, Cu, Xe, Cs, Pt, Au, Np, Pu isotope chains using two interaction parameter sets NL-3 and NL-Z, and compared the relative errors of the even-even nuclei with those of odd-even nuclei and odd-odd nuclei. We find that the errors of binding energy of odd-even and odd-odd nuclei are not bigger than the one of even-even nuclei. The result shows that comparing with even-even nuclei, there is no systematic error and approximation in the calculations of the binding energy of odd-even and odd-odd nuclei with relativistic mean-field theory. In addition, the result is explained theoretically.展开更多
Alarm flood is one of the main problems in the alarm systems of industrial process. Alarm root-cause analysis and alarm prioritization are good for alarm flood reduction. This paper proposes a systematic rationalizati...Alarm flood is one of the main problems in the alarm systems of industrial process. Alarm root-cause analysis and alarm prioritization are good for alarm flood reduction. This paper proposes a systematic rationalization method for multivariate correlated alarms to realize the root cause analysis and alarm prioritization. An information fusion based interpretive structural model is constructed according to the data-driven partial correlation coefficient calculation and process knowledge modification. This hierarchical multi-layer model is helpful in abnormality propagation path identification and root-cause analysis. Revised Likert scale method is adopted to determine the alarm priority and reduce the blindness of alarm handling. As a case study, the Tennessee Eastman process is utilized to show the effectiveness and validity of proposed approach. Alarm system performance comparison shows that our rationalization methodology can reduce the alarm flood to some extent and improve the performance.展开更多
Heat balance of urban ecosystem is a key point for the study of urban climate and micro-climate pattern and its change mechanism. Urban heat island effect is becoming increasingly serious,which is mainly caused by the...Heat balance of urban ecosystem is a key point for the study of urban climate and micro-climate pattern and its change mechanism. Urban heat island effect is becoming increasingly serious,which is mainly caused by the change of the earth's surface cover and the anthropogenic heat release. In this study,the simulation experiment for the anthropogenic heat release was designed according to the heat balance principle. A set of buildings of miniature city were used to constitute the residential area,U grooves were applied to simulate the single building,and the fluorescent lamps in the U groove were regarded as the heat sources of the anthropogenic heat release. The simulation experiment was launched with long-short wave sun photometer,sonic anemothermometer and heat flow gauge in the experiment site. Then the net solar radiation,sensible heat flux and heat flux into the ground were determined. The quantities of the anthropogenic heat release were calculated based on the heat balance principle,and were compared with the theoretical power consumption of the fluorescent lamps. The root mean square error( RMSE) of the simulation for the anthropogenic heat release reaches0. 078 W·m- 2,a comparatively high precision,which showes that the anthropogenic heat release can be accurately determined through the simulation experiments. This study provided a scientific method for the purpose of monitoring the anthropogenic heat release.展开更多
基金Supported by the Effect and Mechanism of Gel-based Controlled Release Fertilizers on Controlling the Nutrient Loss in Soil Erosion (10501-291)Research and Demonstration of New Special Fertilizer for Seawater Fishes and Shellfish (2012-931)+1 种基金Key Techniques and Demonstration of Tobacco Controlled Release Fertilizer Industrialization (2012-045)Research and Application of Gel-based Controlled Release Fertilizers (2002N002)~~
文摘[Objective] This study aimed to investigate the effects of gel-based controlled release fertilizers (CRFs) on agronomic characteristics and physiological indices of corn. [Method] Pot experiment was carried out to investigate the agronomic characteristics and physiological indices of corn fertilized with controlled release fertilizers compared with conventional fertilizer (CF). [Result] Plant height, stem girth, leaf area and root volume of corn were significantly increased under the CRF treatments; photosynthetic rate and soluble protein content were also improved. Dry matter accumulations under the two CRF treatments were increased by 21.3% and 17.0% compared with CF application at one time (CF1), and 19.6% and 15.4% with CF application at two times (CF2), respectively. Accumulation amounts of N, P and K in whole plant under the two CRF treatments were increased by 44.0% -24.7% , 40.0%-25.9% and 20.1% -13.9% ; and the nutrient use efficiencies of N, P and K were improved by 22.9% -13.4% , 11.2% -9.6% and 17.5% -12.1% , respectively. [Conclusion] The results implied that the CRFs could significantly improve nutrient use efficiency and plant yield.
文摘Aim In vitro dissolution test and pharmacokinetics in beagle dogs wereconducted to assess the formulation of tretinoin in self-emulsifying systems. Methods Theconcentrations of tretinoin were determined by HPLC. A crossover study was performed in four fastingbeagle dogs with the formulation of self-emulsifying systems and commercial capsules. Results Theresults showed that the dissolution rate in 15 min of tretinoin in self-emulsifying systems washigher than 80% while that of the commercial capsules was lower than 5% . The area under the plasmaconcentration-time curve (AUC) of the self-emulsifying formulation was significantly higher andC_(max) was approximately two times greater than those of commercial capsule, respectively, Inaddition, the time taken to reach peak was shorter (2 h to 1.25 h) for self-emulsifying formulationof tretinoin. Conclusion The self-emulsifying drug delivery systems.can significantly increasetretinoin in vitro dissolution and in vivo absorption.
基金supported by the Chinese Natural Science Foundation Project (Grant No. 30970784 and 81171455)a National Distinguished Young Scholars Grant (Grant No. 31225009) from the National Natural Science Foundation of China+5 种基金the National Key Basic Research Program of China (Grant No. 2009CB930200)the Chinese Academy of Sciences (CAS) ‘Hundred Talents Program’ (Grant No. 07165111ZX)the CAS Knowledge Innovation Program, and the State HighTech Development Plan (Grant No. 2012AA020804)the ‘Strategic Priority Research Program’ of the Chinese Academy of Sciences (Grant No. XDA09030301)NIH/NIMHD 8 G12 MD007597USAMRMC W81XWH-10-1-0767 grants
文摘In the fight against cancer, controlled drug delivery systems have emerged to enhance the therapeutic efficacy and safety of anti-cancer drugs. Among these systems, mesoporous silica nanoparticles (MSNs) with a functional surface possess obvious advantages and were thus rapidly developed for cancer treatment. Many stimuli-responsive materials, such as nanopartides, polymers, and inorganic materials, have been applied as caps and gatekeepers to control drug release from MSNs. This review presents an overview of the recent progress in the production of pH-responsive MSNs based on the pH gradient between normal tissues and the tumor microenvironment. Four main categories of gatekeepers can respond to acidic conditions. These categories will be described in detail.
基金Supported by the National Natural Science Foundation of China (No.20376038) and the Research Foundation of the Ministry ofEducation of China (No.2002003056).
文摘The auto-gelling and drug release properties of the thermosensitive chitosan-β-glycerophosphate formulation were investigated. According to rheological study, gelation lag time of chitosan/β-glycerophosphate (GP) solutions varied from 2 to 60min with different deacetylation degree of chitosan, pH, gelation temperature, and the particles in the sol. The gelation properties were also found to influence the release profilles of a hydrophilic drug, 5-fluorouracil (5-FU). Morphological examination by scanning electron microphotography demonstrated that large "pores" occurred during the gel-forming process, which created hydrophilic environment and led to the rapid initial release of the drug (85% in f'LrSt 8h). Poly-3-hydroxybutyrate (PHB), a biodegradable material, was applied here as scaffold to capture 5-FU into microparticles with high encapsulation efficiency by solvent-nonsolvent method. Combination of these microparticles into the chitosan-β-GP formulation could drop the rapid initial release from 85% down to 29% in the optimized PHB content (75%, by mass). The release could sustain for about 10 months. Tiffs study provided an understanding of the potential of injectable implant using thermosensitive chitosan-β-GP formulation containing PHB based particles for the water soluble drugs that need the property of long-term delivery.
基金Project(50876116)supported by the National Natural Science Foundation of China
文摘In order to acquire the flow pattern and investigate the settling behavior of the red mud in the separation thickener,computational fluid dynamics(CFD),custom subroutines and agglomerates settling theory were employed to simulate the three-dimensional flow field in an industrial scale thickener with the introduction of a self-dilute feed system.The simulation results show good agreement with the measurement onsite and the flow patterns of the thickener are presented and discussed on both velocity and concentration field.Optimization experiments on feed well and self-dilute system were also carried out,and indicate that the optimal thickener system can dilute the solid concentration in feed well from 110 g/L to 86 g/L which would help the agglomerates' formation and improve the red mud settling speed.Furthermore,the additional power of recirculation pump can be saved and flocculants dosage was reduced from 105g/t to 85g/t in the operation.
基金Supported by the National ]qatural Science Foundation of China (20906064), the National Basic Research Program of China (2009CB623407), the Program for Changjiang Scholars and Innovative Research Team in University (IRTl163), and the Foundation for the Author of National Excellent Doctoral Dissertation of China (201163).
文摘Halloysite nanotube-composited thermo-responsive hydrogel system has been successfully developed for controlled drug release by copolymerization of N-isopropylacrylamide (NIPAM) with silane-modified halloysite nanotubes (HNT) through thermally initiated free-radical polymerization. With methylene blue as a model drug, thermo-responsive drug release results demonstrate that the drug release from the nanotubes in the composited hy-drogel can^be well controlled by manipulating the environmental temperature. When the hydrogel network is swol- len at temperature below the lower critical solution temperature (LCST), drug releases steadily from lumens of the embedded nanotubes, whereas the drug release stops when hydrogel shrinks at temperature above the LCST. The release of model drug from the HNT-composited hydrogel matches well with its thermo-responsive volume phasetransition, and shows characteristics of well controlled release. The design strategy and release results of the pro- posed novel HNT-composited thermo-responsive hydrogel system provide valuable guidance for designing respon- s_i_ve nanocomposites for controlled-release of active agents.
基金Projects(2007BAK22B04, 2006BAB02B05) supported by the National 11th Five-Year Science and Technology Supporting Plan of ChinaProject(50490274) supported by the National Natural Science Foundation of China
文摘According to the mining method for Dongguashan Copper Mine and Tongkeng Mine in China, and with the help of the cavity monitoring system(CMS) and mining software Surpac, the 3D cavity models were established exactly. A series of correlative techniques for calculating stope over-excavation and under-excavation, stope dilution and ore loss rates, and the blasting design of the pillar with complicated irregular boundaries were developed. These techniques were applied in Dongguashan Copper Mine and Tongkeng Mine successfully. Using these techniques, the dilution rates of stopes 52-2^#, 52-6^#, 52-8^#and 52-10^# of Dongguashan Copper Mine are calculated to be 2.12%, 8.46%, 12-67% and 10.68%, respectively, and the ore loss rates of stopes 52-6^# and 5-8^# are 4.41% and 3.70%, severally. Furthermore, according to the design accomplished by the technique for a pillar of Tongkeng Mine with irregular boundary, the volume, total length of boreholes and the dynamite quantity of the pillar are computed to be 1.2 ×10^4 m^3, 2.98 km and 10.97 t, correspondingly.
基金Projects 50221402, 50490271 and 50025413 supported by the National Natural Science Foundation of Chinathe National Basic Research Program of China (2009CB219603, 2009 CB724601, 2006CB202209 and 2005CB221500)+1 种基金the Key Project of the Ministry of Education (306002)the Program for Changjiang Scholars and Innovative Research Teams in Universities of MOE (IRT0408)
文摘In order to carry out numerical simulation using geologic structural data obtained from Landmark(seismic interpretation system), underground geological structures are abstracted into mechanical models which can reflect actual situations and facilitate their computation and analyses.Given the importance of model building, further processing methods about traditional seismic interpretation results from Landmark should be studied and the processed result can then be directly used in numerical simulation computations.Through this data conversion procedure, Landmark and FLAC(the international general stress software) are seamlessly connected.Thus, the format conversion between the two systems and the pre-and post-processing in simulation computation is realized.A practical application indicates that this method has many advantages such as simple operation, high accuracy of the element subdivision and high speed, which may definitely satisfy the actual needs of floor grid cutting.
文摘In the present paper, the author makes some comments on the holistic action of acupuncture from the regulative effect on the nerve-endocrine-immune network, and the close relationship between the nerve-endocrine-immune network and the meridian-collateral system of TCM. The wholism concept of TCM refers to the organism being an integrated entirety, and the regulatory effect of acupuncture on functional activities of the organism relies on the integral connection of the acupoint-meridian-collateral-zangfu-organ system. When stimulated with acupuncture, the human body will brings its potential force into full play in preventing and treating diseases.
文摘Objective:This study aimed to lay the foundation for the research on Panax notoginseng saponins(PNS)in pH-sensitive in situ gel and the development and improvement of related preparations.Methods:We used Carbopol■940,a commonly used pH-sensitive polymer,and the thickener hydroxypropyl methylcellulose(HPMC E4M)as an ophthalmic gel matrix to prepare an ophthalmic in situ gel of PNS.In addition,formula optimization was performed by assessing gelling capability with the results of in vitro release studies.In vitro(corneal permeation,rheological,and stability)and in vivo(ocular irritation and preliminary pharmacokinetics in the vitreous)studies were also performed.Results:The results demonstrated that the in situ gelling systems containing PNS showed a sustained release of the drug,making it an ideal ocular delivery system for improving posterior ocular bioavailability.Conclusions:This study lays the foundation for the research of PNS contained in an in situ pH-triggered gel as well as the development and improvement of related preparations.It concurrently traditional Chinese medicine with a contemporary in situ gelling approach to provide new directions for the treatment of posterior ocular diseases such as diabetic retinopathy.
基金Project(21376271)supported by the National Natural Science Foundation of ChinaProject(2016TP1007)supported by the Hunan Provincial Science and Technology Plan Project,ChinaProjects(201810533078,S2020105330395)supported by the Undergraduates Innovative Training Foundation of Central South University,China。
文摘A light and temperature dual responsive copolymer,poly(7-(4-vinylbenzy-loxyl)-4-methylcoumarin-co-N vinyl caprolactam-co-tri(ethylene glycol)methyl ether methacrylate)(PVNM),was grafted on the surface of dopamine based mesoporous silica nanoparticles(MSNs).The resulting polymer brush,MSNs-g-PVNM,was characterized by FT-IR,TEM,TGA and XPS.The dual responsive behaviors of MSNs-g-PVNM were systematically studied.With imidacloprid as the model guest pesticide,the loading percentage and loading efficiency of the polymer brush were determined as 9.2%and 40.6%,respectively.The release efficiency of imidacloprid in MSNs-g-PVNM was the lowest value of 5.4%at 20℃ and 365 nm,and it reached the highest value of 52.4%at 50℃ and 254 nm.The loss percentage of imidacloprid on the leaves contained imidacloprid-loaded MSNs-g-PVNM(8.4%)was much less than that contained only imidacloprid(25.2%)after three rinses.It was confirmed that the release process of imidacloprid was well regulated through changing external conditions such as light and temperature.
文摘3D seismic prospecting in mining areas of Xieqiao Colliery is a successfulmodel for an advancement from the resource prospecting to mining prospecting stagein coal fields. Its results have proved that faults with a throw of 5-10 m can be detected in an area with good seismogeologic conditions by using 3D seismic technique.Detection of underground tunnels for the first time utilizing 3D seismic data indicates that subsided columns, gotten and mine goaf can be detected using 3D seismic technique, so it has a broad applied prospect.
文摘Objective:The cross-linked production,which was prepared by HA and cross-linking agent STMP,EDC,GP through cross-linking reaction,might be used in drug delivery system(DDS).To ensure the security of clinical application,the excellent properties such as none cell toxicity,nonirritant,none general toxicity,none immunological rejection are necessary.Methods:In accordance with the request of GB/T 16886.1 on security evaluation of medical biomaterials,cell toxicity test,hemolysis test,intracutaneous stimulation test,acute toxicity test,and hypersensitive test were required.Results:Cell toxicity of HA-STMP,HA-EDC,HA-GP were all less than 1.All hypersensitive tests were eligible.But HA-EDC,HA-GP produced different degrees of slight thrill,slight toxicity,hemolysis rate,which were larger than the standard value.Conclusion:HA-STMP possesses favourable biocompatibility,which is a kind of ideal biomaterials and drug carriers.
基金supported by the National Science Foundation of China(No.41404070)China Geological Survey(No.DD20160102-02)
文摘Chile is a very important country that forms part of the Andean metallogenic belts. The Atacama and Domeyko fault systems in northern Chile control the tectonic- magmatic activities that migrate eastward and the types of mineral resources. In this paper, we processed and interpreted aeromagnetic data from northern Chile using reduction to pole, upward field continuation, the second derivative calculation in the vertical direction, inclination angle calculation, and analytical signal amplitude analysis. We revealed the locations and planar distribution characteristics of the regional deep faults along the NNE and NS directions. Furthermore, we observed that the major reasons for the formation of the tectonic-magmatic rocks belts were the nearly parallel deep faults distributed from west to east and multiple magmatic activities along these faults. We ascertained the locations of volcanic mechanisms and the relationships between them using these regional deep faults. We deduced the spatial distributions of the basic-intermediate, basic, and acidic igneous rocks, intrusive rocks, and sedimentary sequences. We showed the linear positive magnetic anomalies and magnetic anomaly gradient zones by slowly varying the background, negative magnetic anomaly field, which indicated the presence of strong magmatic activities in these regional deep faults; it also revealed the favorable areas of copper and polymetallic mineralization. This study provides some basic information for further research on the geology, structural characteristics, and mineral resource prospecting in northern Chile.
基金sponsored by statutory research University of Science and Technology AGH,Cracow,Poland(No.11 100 281)
文摘In some worldwide hard coal basins recovery of methane from virgin coal beds is difficult. In general,mentioned difficulties are related to geo-mechanical, petrographical and physical-chemical properties of coals in question, occurring for example in the Bowen Basin(Australia) or the Upper Silesian Coal Basin(Poland). Among numerous properties and parameters, the following are very essential: susceptibility of coal beds to deformation connected with coal stress state change and contemporary shrinkage of the coal matrix during methane desorption. Those adverse geo-mechanical and physical-chemical effects are accompanied by essential change of the porous coal structure, which under these disadvantageous conditions is very complex. This study aims to show difficulties, which occur in phase of recognition of the methane-reach coal deposit. Volume absorbed methane(not surface adsorbed) in sub-micropores having minimal size comparable with gas molecule diameter must possess energy allowing separation of the nodes and methane release to micropores.
文摘The critical properties of the bond-diluted mixed spin-1/2 and spin-1 transverse Ising system with singleion anisotropy are investigated by means of the effective field theory with correlations. Particular emphasis is given to the square lattice for which phase diagrams are obtained. If transverse field varies in the certain ranges we find that the tricritical point is obtained for the value of the bond concentration in a restricted region. We also observe that the reentrant phase transition may occur in the present system if single-ion anisotropy parameter is not large and if transverse field is small. On the other hand, for certain values of the system parameters, new induced magnetic ordering can be obtained. We find a number of interesting phenomena that are not predicted by previous literatures. The influence of the transverse field on the behaviours of the reentrant phase transition and induced magnetic ordering is discussed. A detailed description of the phase transition is presented.
基金Project(51275205)supported by the National Natural Science Foundation of China
文摘A new method of system failure analysis was proposed. First, considering the relationships between the failure subsystems,the decision making trial and evaluation laboratory(DEMATEL) method was used to calculate the degree of correlation between the failure subsystems, analyze the combined effect of related failures, and obtain the degree of correlation by using the directed graph and matrix operations. Then, the interpretative structural modeling(ISM) method was combined to intuitively show the logical relationship of many failure subsystems and their influences on each other by using multilevel hierarchical structure model and obtaining the critical subsystems. Finally, failure mode effects and criticality analysis(FMECA) was used to perform a qualitative hazard analysis of critical subsystems, determine the critical failure mode, and clarify the direction of reliability improvement.Through an example, the result demonstrates that the proposed method can be efficiently applied to system failure analysis problems.
基金The project supported by National Natural Science Foundation of China under Grant No. 10475026 (2004)
文摘We calculate the binding energies of Ni, Cu, Xe, Cs, Pt, Au, Np, Pu isotope chains using two interaction parameter sets NL-3 and NL-Z, and compared the relative errors of the even-even nuclei with those of odd-even nuclei and odd-odd nuclei. We find that the errors of binding energy of odd-even and odd-odd nuclei are not bigger than the one of even-even nuclei. The result shows that comparing with even-even nuclei, there is no systematic error and approximation in the calculations of the binding energy of odd-even and odd-odd nuclei with relativistic mean-field theory. In addition, the result is explained theoretically.
基金Supported by the National Natural Science Foundation of China(61473026,61104131)the Fundamental Research Funds for the Central Universities(JD1413)
文摘Alarm flood is one of the main problems in the alarm systems of industrial process. Alarm root-cause analysis and alarm prioritization are good for alarm flood reduction. This paper proposes a systematic rationalization method for multivariate correlated alarms to realize the root cause analysis and alarm prioritization. An information fusion based interpretive structural model is constructed according to the data-driven partial correlation coefficient calculation and process knowledge modification. This hierarchical multi-layer model is helpful in abnormality propagation path identification and root-cause analysis. Revised Likert scale method is adopted to determine the alarm priority and reduce the blindness of alarm handling. As a case study, the Tennessee Eastman process is utilized to show the effectiveness and validity of proposed approach. Alarm system performance comparison shows that our rationalization methodology can reduce the alarm flood to some extent and improve the performance.
基金supported by the National Natural Science Foundation of China ( No. 40971187 and 41472243 )the Funded By Open Research Fund Program of Key Laboratory of Digital Mapping and Land Information Application Engineering,National Administration of Surveying,Mapping and Geoinformation ( No. GCWD201402 )
文摘Heat balance of urban ecosystem is a key point for the study of urban climate and micro-climate pattern and its change mechanism. Urban heat island effect is becoming increasingly serious,which is mainly caused by the change of the earth's surface cover and the anthropogenic heat release. In this study,the simulation experiment for the anthropogenic heat release was designed according to the heat balance principle. A set of buildings of miniature city were used to constitute the residential area,U grooves were applied to simulate the single building,and the fluorescent lamps in the U groove were regarded as the heat sources of the anthropogenic heat release. The simulation experiment was launched with long-short wave sun photometer,sonic anemothermometer and heat flow gauge in the experiment site. Then the net solar radiation,sensible heat flux and heat flux into the ground were determined. The quantities of the anthropogenic heat release were calculated based on the heat balance principle,and were compared with the theoretical power consumption of the fluorescent lamps. The root mean square error( RMSE) of the simulation for the anthropogenic heat release reaches0. 078 W·m- 2,a comparatively high precision,which showes that the anthropogenic heat release can be accurately determined through the simulation experiments. This study provided a scientific method for the purpose of monitoring the anthropogenic heat release.