BACKGROUND Inflammatory bowel disease(IBD)is a common chronic intestinal inflammatory disease.High oxidative stress is a treatment target for IBD.Cerium oxide(CeO2)nanomaterials as nanozymes with antioxidant activity ...BACKGROUND Inflammatory bowel disease(IBD)is a common chronic intestinal inflammatory disease.High oxidative stress is a treatment target for IBD.Cerium oxide(CeO2)nanomaterials as nanozymes with antioxidant activity are potential drugs for the treatment of colitis.AIM To synthesize hollow cerium(H-CeO2)nanoparticles by one-step method and to validate the therapeutic efficacy of H-CeO2 in IBD.METHODS H-CeO2 was synthesized by one-step method and examined its characterization and nanoenzymatic activity.Subsequently,we constructed dextran sulfate so-dium(DSS)-induced colitis in mice to observe the effects of H-CeO2 on colonic inflammation.The effects of H-CeO2 on colon inflammation and reactive oxygen species(ROS)levels in IBD mice were detected by hematoxylin and eosin staining and dichlorofluorescein diacetate staining,respectively.Finally,the biological sa-fety of H-CeO2 on mice was evaluated by hematoxylin and eosin staining,blood routine,and blood biochemistry.RESULTS H-CeO2 nanoparticles prepared by the one-step method were uniform,monodi-sperse and hollow.H-CeO2 had a good ability to scavenge ROS,∙OH and∙OOH.H-CeO2 reduced DSS-induced decreases in body weight and colon length,colonic epithelial damage,inflammatory infiltration,and ROS accumulation.H-CeO2 administration reduced the disease activity index of DSS-induced animals from about 8 to 5.H-CeO2 had no significant effect on body weight,total platelet count,hemoglobin,white blood cell,and red blood cell counts in healthy mice.No significant damage to major organs was observed in healthy mice following H-CeO2 administration.CONCLUSION The one-step synthesis of H-CeO2 nanomaterials had good antioxidant activity,biosafety,and inhibited deve-lopment of DSS-induced IBD in mice by scavenging ROS.展开更多
High shear wet granulation(HSWG) is one of the most poorly understood processes with known difficulties in optimization and scale up. The purpose of the current study is to develop a DEM model which can be applied und...High shear wet granulation(HSWG) is one of the most poorly understood processes with known difficulties in optimization and scale up. The purpose of the current study is to develop a DEM model which can be applied under dynamic process conditions with high predictive capacity to improve process insight. The DEM model is used to predict agglomeration as a function of impeller speed and liquid addition rate in a high shear wet granulator. The DEM model tracks dynamic formation and breakage of liquid bridges between particles as liquid binder in the system is added, and corrects for the change in material properties as a function of the binder content.展开更多
Gradiently denitrated gun propellant(GDGP)prepared by a“gradient denitration”strategy is obviously superior in progressive burning performance to the traditional deterred gun propellant.Currently,the preparation of ...Gradiently denitrated gun propellant(GDGP)prepared by a“gradient denitration”strategy is obviously superior in progressive burning performance to the traditional deterred gun propellant.Currently,the preparation of GDGP employed a tedious two-step method involving organic solvents,which hinders the large-scale preparation of GDGP.In this paper,GDGP was successfully prepared via a novelty and environmentally friendly one-step method.The obtained samples were characterized by FT-IR,Raman,SEM and XPS.The results showed that the content of nitrate groups gradiently increased from the surface to the core in the surface layer of GDGP and the surface layer of GDGP exhibited a higher compaction than that of raw gun propellant,with a well-preserved nitrocellulose structure.The denitration process enabled the propellant surface with regressive energy density and good progressive burning performance,as confirmed by oxygen bomb and closed bomb test.At the same time,the effects of different solvents on the component loss of propellant were compared.The result showed that water caused the least component loss.Finally,the stability of GDGP was confirmed by methyl-violet test.This work not only provided environmentally friendly,simple and economic preparation of GDGP,but also confirmed the stability of GDGP prepared by this method.展开更多
In this paper, a new computational method for improving the accuracy of numerically computed solutions is introduced. The computational method is based on the one-step method and conserved quantities of holonomic syst...In this paper, a new computational method for improving the accuracy of numerically computed solutions is introduced. The computational method is based on the one-step method and conserved quantities of holonomic systems are considered as kinematical constraints in this method.展开更多
The microwave absorbents of Fe and C nanoparticles as magnetic loss and dielectric loss material respectively were composited with the polyvinyl alcohol(PVA)as binder by spray granulation method,The electromagnetic pa...The microwave absorbents of Fe and C nanoparticles as magnetic loss and dielectric loss material respectively were composited with the polyvinyl alcohol(PVA)as binder by spray granulation method,The electromagnetic parameters of Fe and C composite particles were analyzed by vector network.The complex permittivity and magnetic permeability of Fe and C composite particles matched well with increasing C nanoparticle content,and then the microwave loss property was improved.A minimum reflection loss(RL)of-42.7 dB at 3.68 GHz for a composite with 4.6 mm in thickness can be obtained when the content ratio of the C nanoparticles,the modified Fe nanoparticles and the PVA is 21:49:30(Sample 3).展开更多
In order to control the accumulation of SiC ceramic particles on the wall of the rotating chamber in the frame of a dry granulation process,the effect of the wall reverse speed on the mixing process is investigated.In...In order to control the accumulation of SiC ceramic particles on the wall of the rotating chamber in the frame of a dry granulation process,the effect of the wall reverse speed on the mixing process is investigated.In particular,an Euler-Euler two-phase flow model is used to analyze the dynamics of both SiC particles and air.The numerical results show that by setting a certain reverse rotating speed of the rotating chamber,the accumulation of SiC particles on the wall can be improved,i.e.,their direction of motion in proximity to the wall can be changed and particles can be forced to re-join the granulation process.Experimental tests conducted to verify the reliability of the numerical findings,demonstrate that when the reverse rotating speed of the rotating chamber is 4 r/min,the sphericity of SiC particles in the rotating chamber is the highest and the fluidity is the best possible one.展开更多
In order to reveal the intrinsic fluid-dynamic mechanisms of a pressure-swirl nozzle used for Si3N4 dry granulation,and effectively predict its external spray characteristics,the dynamics of air-atomized liquid two-ph...In order to reveal the intrinsic fluid-dynamic mechanisms of a pressure-swirl nozzle used for Si3N4 dry granulation,and effectively predict its external spray characteristics,the dynamics of air-atomized liquid two-phase flow is analyzed using a VOF(Volume of Fraction)method together with the modified realizable k-εturbulence model.The influence of nozzle orifice shape on velocity distribution,pressure distribution is studied.The results show that the pressure difference in a convergent conical nozzle is the largest with a hollow air core being formed in the nozzle.The corresponding velocity of atomized liquid at nozzle orifice is the largest.Using a self-designed atomization experiment platform,the velocity and pressure of atomized liquid and the spray cone angle are measured for three nozzles with different orifice shapes.The micro-morphology of Si3N4 particles is also determined.These data confirm the correctness of numerical simulation.Considering atomization performance of the nozzle,the contraction conical nozzle is more suitable for the atomization of Si3N4 in practical production based on the dry granulation approach.展开更多
A novel method isolated microorganisms in soil granule was built. The key steps included： repeated elutriation of soil by sterilized water, inoculation on the plates with the elutriated sediments, incubation of the p...A novel method isolated microorganisms in soil granule was built. The key steps included： repeated elutriation of soil by sterilized water, inoculation on the plates with the elutriated sediments, incubation of the plates and isolation of the actinomycetes by using selected culture medium. We formulated that most microflora included the dominant actinomycetes in the soil were carried away with the sterilized water in the elutriation procedure, some rare actinomycetes and few other microflora included bacteria were remained in the elutriated sediments, the other microflora were excluded to grew into colonies on the plates by using selective culture medium for actinomycetes in the elutriated sediments. Results showed the supposition. Non-streptomycete actinomycetes were isolated both from black soil samples from Chinese northeast area and compost samples from Chinese central area. Soil fungi in granule were isolated by using the selective conditions to favor fungi. The results showed that the method was effective展开更多
A computational method of constraint stabilization and correction is introduced. The method is based on the Baumgart＇s one-step method. Constraint conditions are addressed to stabilize and correct the solution. Two e...A computational method of constraint stabilization and correction is introduced. The method is based on the Baumgart＇s one-step method. Constraint conditions are addressed to stabilize and correct the solution. Two examples are given to illustrate the results of the method.展开更多
This paper deals with a comparative research between two processes of granulation, namely mini-pelletized sintering （MPS） and hybrid pelletized sintering （HPS）, focusing on aspects such as the balling effect, prod...This paper deals with a comparative research between two processes of granulation, namely mini-pelletized sintering （MPS） and hybrid pelletized sintering （HPS）, focusing on aspects such as the balling effect, production, quality, and mineralography and metallurgical performance of sinter. The results indicate that both methods can result in a satisfying capability in balling effect and metallurgical performance of sinter, qualified to meet the plant production requirements, but when the granulation time and granulating moisture are set to around 6 minutes and 7.0% respectively, MPS is better than HPS.展开更多
Metal clusters RCCo_3(CO)_9(R-H,C1,Br,CH_3,Ph) were prepared in 18.8-57.3% yields from the reaction of cobalt(Ⅱ)salt and RCX_a under mild PTC conditions(latm CO,25℃).The cobalt salt was reduced to Co(CO)_4 in the pr...Metal clusters RCCo_3(CO)_9(R-H,C1,Br,CH_3,Ph) were prepared in 18.8-57.3% yields from the reaction of cobalt(Ⅱ)salt and RCX_a under mild PTC conditions(latm CO,25℃).The cobalt salt was reduced to Co(CO)_4 in the presence of Na_3S_2O_4.展开更多
The Co content dependence of crystal structure and specific magnetization of Fe1-xCox-SiO2granular solid prepared by the sol-gel method have been studied. It is found that the crystal structure, Iattice parameter and ...The Co content dependence of crystal structure and specific magnetization of Fe1-xCox-SiO2granular solid prepared by the sol-gel method have been studied. It is found that the crystal structure, Iattice parameter and specific magnetization of the FeCo alloy particles depend on the Co content.展开更多
Cd S/Mo S2,an extremely efficient photocatalyst,has been extensively used in hydrogen photoproduction and pollutant degradation.Cd S/Mo S2can be synthesized by a facile one-step hydrothermal process.However,the effect...Cd S/Mo S2,an extremely efficient photocatalyst,has been extensively used in hydrogen photoproduction and pollutant degradation.Cd S/Mo S2can be synthesized by a facile one-step hydrothermal process.However,the effect of the sulfur source on the synthesis of Cd S/Mo S2via one-step hydrothermal methods has seldom been investigated.We report herein a series of one-step hydrothermal preparations of Cd S/Mo S2using three different sulfur sources：thioacetamide,L-cysteine,and thiourea.The results revealed that the sulfur source strongly affected the crystallization,morphology,elemental composition and ultraviolet（UV）–visible-light-absorption ability of the Cd S/Mo S2.Among the investigated sulfur sources,thioacetamide provided the highest visible-light absorption ability for Cd S/Mo S2,with the smallest average particle size and largest surface area,resulting in the highest efficiency in Methylene Blue（MB）degradation.The photocatalytic activity of Cd S/Mo S2synthesized from the three sulfur sources can be arranged in the following order：thioacetamideL-cysteinethiourea.The reaction rate constants（k）for thioacetamide,L-cysteine,and thiourea were estimated to be 0.0197,0.0140,and 0.0084 min^（-1）,respectively.However,thioacetamide may be limited in practical application in terms of its price and toxicity,while L-cysteine is relatively economical,less toxic and exhibited good photocatalytic degradation performance toward MB.展开更多
According to the amino acid sequence and codon preference of E. coli, the human interleukin-18（IL-18） gene was optimized to avoid the rare codons. The total length of the synthesized gene is 571 bp; 18 oligonucleoti...According to the amino acid sequence and codon preference of E. coli, the human interleukin-18（IL-18） gene was optimized to avoid the rare codons. The total length of the synthesized gene is 571 bp; 18 oligonucleotides, DNA fragments were designed and synthesized by the phosphoramidite four-step chemical method. The whole DNA sequence was synthesized by a one-step total gene synthesis method, and then inserted in pUC18 vector. Five positive clones identified by blue-white colony screening were sent to Shanghai Sangon Biological Engineering Technology and Service Co., Ltd. for sequencing. The sequencing result shows that one clone contained the complete correct gene in all the five positive clones.展开更多
In order to reveal the force transmission features of the granules in the solid granule medium forming(SGMF) technology,the frictional characteristics of the non-metallic granule medium(NGM) under high pressure were i...In order to reveal the force transmission features of the granules in the solid granule medium forming(SGMF) technology,the frictional characteristics of the non-metallic granule medium(NGM) under high pressure were investigated by tests and simulations.And the relevant changing curves of the internal friction coefficient of the granular system under different normal pressures were obtained by self-designed shear test.By the granule volume compression test,the accurate discrete element simulation parameters were obtained,based on this,the discrete element method(DEM) was adopted to reveal the evolution law of the NGM granules movement in the sample shear process from the microscopic view.Based on the DEM,the influence of granule diameter,surface friction coefficient,normal pressure and shear velocity on the internal friction coefficient of the granular system were studied.And the parameters were conducted to be dimensionless by introducing the inertia coefficient.Finally,the expression showing power-law relationship of inertia coefficient,surface friction coefficient and internal friction coefficient is obtained.展开更多
Recently, the incidence of<span> </span><i><span>Candida</span></i><span> infections has substantially increased. Conventional identification methods for </span><...Recently, the incidence of<span> </span><i><span>Candida</span></i><span> infections has substantially increased. Conventional identification methods for </span><i><span>Candida</span></i><span> species are technically difficult to conduct and cannot accurately distinguish each species. The purpose of the present study was to design primers to identify and detect simultaneously</span><span> </span><span>eight medically important </span><i><span>Candida</span></i><span> species using one-step multiplex PCR. PCR primers were designed based on partial sequences of intergenic spacer (IGS) and internal transcribed spacer (ITS) genes of eight medically important </span><i><span>Candida</span></i><span> species. These primers were able to distinguish each </span><i><span>Candida</span></i><span> species and did not display cross-reactivity with representative </span><i><span>Candida </span></i><span>species other than the eight</span><i><span> Candida</span></i><span> species. Moreover, our developed one-step multiplex PCR method is accurate, specific, cost-effective, time-saving, and worked without requiring DNA extraction.</span>展开更多
The bulk metal forming processes were simulated by using a one-step finite element(FE)approach based on deformation theory of plasticity,which enables rapid prediction of final workpiece configurations and stress/stra...The bulk metal forming processes were simulated by using a one-step finite element(FE)approach based on deformation theory of plasticity,which enables rapid prediction of final workpiece configurations and stress/strain distributions.This approach was implemented to minimize the approximated plastic potential energy derived from the total plastic work and the equivalent external work in static equilibrium,for incompressibly rigid-plastic materials,by FE calculation based on the extremum work principle.The one-step forward simulations of compression and rolling processes were presented as examples,and the results were compared with those obtained by classical incremental FE simulation to verify the feasibility and validity of the proposed method.展开更多
Objective To facilitate the quality evaluation suitable for the unique characteristics of Chinese materia medica(CMM)by developing and implementing a novel approach known as the matching frequency statistical moment(M...Objective To facilitate the quality evaluation suitable for the unique characteristics of Chinese materia medica(CMM)by developing and implementing a novel approach known as the matching frequency statistical moment(MFSM)method.Methods This study established the MFSM method.To demonstrate its effectiveness,we applied this novel approach to analyze Danxi Granules(丹膝颗粒,DXG)and its constituent herbal materials.To begin with,the ultra-performance liquid chromatography(UPLC)was applied to obtain the chromatographic fingerprints of DXG and its constituent herbal materi-als.Next,the MFSM was leveraged to compress and integrate them into a new fingerprint with fewer analytical units.Then,we characterized the properties and variability of both the original and integrated fingerprints by calculating total quantum statistical moment(TQSM)parameters,information entropy and information amount,along with their relative standard deviation(RSD).Finally,we compared the TQSM parameters,information entropy and infor-mation amount,and their RSD between the traditional and novel fingerprints to validate the new analytical method.Results The chromatographic peaks of DXG and its 12 raw herbal materials were divided and integrated into peak families by the MFSM method.Before integration,the ranges of the peak number,three TQSM parameters,information entropy and information amount for each peak or peak family of UPLC fingerprints of DXG and its 12 raw herbal materials were 95.07−209.73,9390−183064μv·s,5.928−21.33 min,22.62−106.69 min^(2),4.230−6.539,and 50530−974186μv·s,respectively.After integration,the ranges of these parameters were 10.00−88.00,9390−183064μv·s,5.951−22.02 min,22.27−104.73 min^(2),2.223−5.277,and 38159−807200μv·s,respectively.Correspondingly,the RSD of all the aforementioned pa-rameters before integration were 2.12%−9.15%,6.04%−49.78%,1.15%−23.10%,3.97%−25.79%,1.49%−19.86%,and 6.64%−51.20%,respectively.However,after integration,they changed to 0.00%,6.04%−49.87%,1.73%−23.02%,3.84%−26.85%,1.17%−16.54%,and 6.40%−48.59%,respectively.The results demonstrated that in the newly integrated fingerprint,the analytical units of constituent herbal materials,information entropy and information amount were significantly reduced(P<0.05),while the TQSM parameters remained unchanged(P>0.05).Additionally,the RSD of the TQSM parameters,information entropy,and information amount didn’t show significant difference before and after integration(P>0.05),but the RSD of the number and area of the integrated analytical units significantly decreased(P<0.05).Conclusion The MFSM method could reduce the analytical units of constituent herbal mate-rials while maintain the properties and variability from their original fingerprint.Thus,it could serve as a feasible and reliable tool to reduce difficulties in analyzing multi-compo-nents within CMMs and facilitating the evaluation of their quality.展开更多
For the traditional one-step formulations of using shell elements, the computations of the curvature variation and bending stiffness matrix were simplified by omitting the rotational DOFs （degrees of freedom） on the...For the traditional one-step formulations of using shell elements, the computations of the curvature variation and bending stiffness matrix were simplified by omitting the rotational DOFs （degrees of freedom） on the basis of initial flat blank and fully known final configuration. They were highly efficient but not suitable either for the forming processes with non-flat initial configurations or for one-step forward and multistep analyses. Thus, a one-step formulation based on the rotation-free BST （Basic Shell Triangle） element was presented. In this formulation, the penalty method was adopted to deal with contacts in the forming processes.展开更多
文摘BACKGROUND Inflammatory bowel disease(IBD)is a common chronic intestinal inflammatory disease.High oxidative stress is a treatment target for IBD.Cerium oxide(CeO2)nanomaterials as nanozymes with antioxidant activity are potential drugs for the treatment of colitis.AIM To synthesize hollow cerium(H-CeO2)nanoparticles by one-step method and to validate the therapeutic efficacy of H-CeO2 in IBD.METHODS H-CeO2 was synthesized by one-step method and examined its characterization and nanoenzymatic activity.Subsequently,we constructed dextran sulfate so-dium(DSS)-induced colitis in mice to observe the effects of H-CeO2 on colonic inflammation.The effects of H-CeO2 on colon inflammation and reactive oxygen species(ROS)levels in IBD mice were detected by hematoxylin and eosin staining and dichlorofluorescein diacetate staining,respectively.Finally,the biological sa-fety of H-CeO2 on mice was evaluated by hematoxylin and eosin staining,blood routine,and blood biochemistry.RESULTS H-CeO2 nanoparticles prepared by the one-step method were uniform,monodi-sperse and hollow.H-CeO2 had a good ability to scavenge ROS,∙OH and∙OOH.H-CeO2 reduced DSS-induced decreases in body weight and colon length,colonic epithelial damage,inflammatory infiltration,and ROS accumulation.H-CeO2 administration reduced the disease activity index of DSS-induced animals from about 8 to 5.H-CeO2 had no significant effect on body weight,total platelet count,hemoglobin,white blood cell,and red blood cell counts in healthy mice.No significant damage to major organs was observed in healthy mice following H-CeO2 administration.CONCLUSION The one-step synthesis of H-CeO2 nanomaterials had good antioxidant activity,biosafety,and inhibited deve-lopment of DSS-induced IBD in mice by scavenging ROS.
基金financial support by PhR MA Foundation Starter Research Grant in Pharmaceutics
文摘High shear wet granulation(HSWG) is one of the most poorly understood processes with known difficulties in optimization and scale up. The purpose of the current study is to develop a DEM model which can be applied under dynamic process conditions with high predictive capacity to improve process insight. The DEM model is used to predict agglomeration as a function of impeller speed and liquid addition rate in a high shear wet granulator. The DEM model tracks dynamic formation and breakage of liquid bridges between particles as liquid binder in the system is added, and corrects for the change in material properties as a function of the binder content.
文摘Gradiently denitrated gun propellant(GDGP)prepared by a“gradient denitration”strategy is obviously superior in progressive burning performance to the traditional deterred gun propellant.Currently,the preparation of GDGP employed a tedious two-step method involving organic solvents,which hinders the large-scale preparation of GDGP.In this paper,GDGP was successfully prepared via a novelty and environmentally friendly one-step method.The obtained samples were characterized by FT-IR,Raman,SEM and XPS.The results showed that the content of nitrate groups gradiently increased from the surface to the core in the surface layer of GDGP and the surface layer of GDGP exhibited a higher compaction than that of raw gun propellant,with a well-preserved nitrocellulose structure.The denitration process enabled the propellant surface with regressive energy density and good progressive burning performance,as confirmed by oxygen bomb and closed bomb test.At the same time,the effects of different solvents on the component loss of propellant were compared.The result showed that water caused the least component loss.Finally,the stability of GDGP was confirmed by methyl-violet test.This work not only provided environmentally friendly,simple and economic preparation of GDGP,but also confirmed the stability of GDGP prepared by this method.
基金Project supported by the National Natural Science Foundation of China （Grant Nos 10572021 and 10372053）, and the Fundamental Research Foundation of Beijing Institute of Technology （BIT-UBF-200507A4206）.
文摘In this paper, a new computational method for improving the accuracy of numerically computed solutions is introduced. The computational method is based on the one-step method and conserved quantities of holonomic systems are considered as kinematical constraints in this method.
基金the support from the National Natural Science Foundation of China(No.51171033)the Fundamental Research Funds for the Central Universities(DUT15LAB05,DUT16LAB03)
文摘The microwave absorbents of Fe and C nanoparticles as magnetic loss and dielectric loss material respectively were composited with the polyvinyl alcohol(PVA)as binder by spray granulation method,The electromagnetic parameters of Fe and C composite particles were analyzed by vector network.The complex permittivity and magnetic permeability of Fe and C composite particles matched well with increasing C nanoparticle content,and then the microwave loss property was improved.A minimum reflection loss(RL)of-42.7 dB at 3.68 GHz for a composite with 4.6 mm in thickness can be obtained when the content ratio of the C nanoparticles,the modified Fe nanoparticles and the PVA is 21:49:30(Sample 3).
基金the National Natural Science Foundation of China(Grant No.51964022).
文摘In order to control the accumulation of SiC ceramic particles on the wall of the rotating chamber in the frame of a dry granulation process,the effect of the wall reverse speed on the mixing process is investigated.In particular,an Euler-Euler two-phase flow model is used to analyze the dynamics of both SiC particles and air.The numerical results show that by setting a certain reverse rotating speed of the rotating chamber,the accumulation of SiC particles on the wall can be improved,i.e.,their direction of motion in proximity to the wall can be changed and particles can be forced to re-join the granulation process.Experimental tests conducted to verify the reliability of the numerical findings,demonstrate that when the reverse rotating speed of the rotating chamber is 4 r/min,the sphericity of SiC particles in the rotating chamber is the highest and the fluidity is the best possible one.
基金the National Natural Science Foundation of China(Grant:51964022).
文摘In order to reveal the intrinsic fluid-dynamic mechanisms of a pressure-swirl nozzle used for Si3N4 dry granulation,and effectively predict its external spray characteristics,the dynamics of air-atomized liquid two-phase flow is analyzed using a VOF(Volume of Fraction)method together with the modified realizable k-εturbulence model.The influence of nozzle orifice shape on velocity distribution,pressure distribution is studied.The results show that the pressure difference in a convergent conical nozzle is the largest with a hollow air core being formed in the nozzle.The corresponding velocity of atomized liquid at nozzle orifice is the largest.Using a self-designed atomization experiment platform,the velocity and pressure of atomized liquid and the spray cone angle are measured for three nozzles with different orifice shapes.The micro-morphology of Si3N4 particles is also determined.These data confirm the correctness of numerical simulation.Considering atomization performance of the nozzle,the contraction conical nozzle is more suitable for the atomization of Si3N4 in practical production based on the dry granulation approach.
基金Supported by the Youth Foundation of College of Resources and Environment of Northeast Agricultural University
文摘A novel method isolated microorganisms in soil granule was built. The key steps included： repeated elutriation of soil by sterilized water, inoculation on the plates with the elutriated sediments, incubation of the plates and isolation of the actinomycetes by using selected culture medium. We formulated that most microflora included the dominant actinomycetes in the soil were carried away with the sterilized water in the elutriation procedure, some rare actinomycetes and few other microflora included bacteria were remained in the elutriated sediments, the other microflora were excluded to grew into colonies on the plates by using selective culture medium for actinomycetes in the elutriated sediments. Results showed the supposition. Non-streptomycete actinomycetes were isolated both from black soil samples from Chinese northeast area and compost samples from Chinese central area. Soil fungi in granule were isolated by using the selective conditions to favor fungi. The results showed that the method was effective
基金the National Natural Science Foundation of China (10572021 ,10372053)Basic Research Foundation of Beijing Institute of Tech-nology (BIT-UBF-200507A4206)
文摘A computational method of constraint stabilization and correction is introduced. The method is based on the Baumgart＇s one-step method. Constraint conditions are addressed to stabilize and correct the solution. Two examples are given to illustrate the results of the method.
文摘This paper deals with a comparative research between two processes of granulation, namely mini-pelletized sintering （MPS） and hybrid pelletized sintering （HPS）, focusing on aspects such as the balling effect, production, quality, and mineralography and metallurgical performance of sinter. The results indicate that both methods can result in a satisfying capability in balling effect and metallurgical performance of sinter, qualified to meet the plant production requirements, but when the granulation time and granulating moisture are set to around 6 minutes and 7.0% respectively, MPS is better than HPS.
文摘Metal clusters RCCo_3(CO)_9(R-H,C1,Br,CH_3,Ph) were prepared in 18.8-57.3% yields from the reaction of cobalt(Ⅱ)salt and RCX_a under mild PTC conditions(latm CO,25℃).The cobalt salt was reduced to Co(CO)_4 in the presence of Na_3S_2O_4.
文摘The Co content dependence of crystal structure and specific magnetization of Fe1-xCox-SiO2granular solid prepared by the sol-gel method have been studied. It is found that the crystal structure, Iattice parameter and specific magnetization of the FeCo alloy particles depend on the Co content.
基金supported by the National Natural Science Foundation of China (No. 51478431)a Science and TechnologyPlanning Project from the Science and Technology Department in Zhejiang Province (No. 2014C33028)funding as a Xinmiao Talent Project of Zhejiang Province (No. 2016R408074)
文摘Cd S/Mo S2,an extremely efficient photocatalyst,has been extensively used in hydrogen photoproduction and pollutant degradation.Cd S/Mo S2can be synthesized by a facile one-step hydrothermal process.However,the effect of the sulfur source on the synthesis of Cd S/Mo S2via one-step hydrothermal methods has seldom been investigated.We report herein a series of one-step hydrothermal preparations of Cd S/Mo S2using three different sulfur sources：thioacetamide,L-cysteine,and thiourea.The results revealed that the sulfur source strongly affected the crystallization,morphology,elemental composition and ultraviolet（UV）–visible-light-absorption ability of the Cd S/Mo S2.Among the investigated sulfur sources,thioacetamide provided the highest visible-light absorption ability for Cd S/Mo S2,with the smallest average particle size and largest surface area,resulting in the highest efficiency in Methylene Blue（MB）degradation.The photocatalytic activity of Cd S/Mo S2synthesized from the three sulfur sources can be arranged in the following order：thioacetamideL-cysteinethiourea.The reaction rate constants（k）for thioacetamide,L-cysteine,and thiourea were estimated to be 0.0197,0.0140,and 0.0084 min^（-1）,respectively.However,thioacetamide may be limited in practical application in terms of its price and toxicity,while L-cysteine is relatively economical,less toxic and exhibited good photocatalytic degradation performance toward MB.
文摘According to the amino acid sequence and codon preference of E. coli, the human interleukin-18（IL-18） gene was optimized to avoid the rare codons. The total length of the synthesized gene is 571 bp; 18 oligonucleotides, DNA fragments were designed and synthesized by the phosphoramidite four-step chemical method. The whole DNA sequence was synthesized by a one-step total gene synthesis method, and then inserted in pUC18 vector. Five positive clones identified by blue-white colony screening were sent to Shanghai Sangon Biological Engineering Technology and Service Co., Ltd. for sequencing. The sequencing result shows that one clone contained the complete correct gene in all the five positive clones.
基金Projects(51305385,51305386)supported by the National Natural Science Foundation of ChinaProject(QN20131080)supported by the Science Research Youth Foundation of Hebei Provincial Colleges and Universities,China
文摘In order to reveal the force transmission features of the granules in the solid granule medium forming(SGMF) technology,the frictional characteristics of the non-metallic granule medium(NGM) under high pressure were investigated by tests and simulations.And the relevant changing curves of the internal friction coefficient of the granular system under different normal pressures were obtained by self-designed shear test.By the granule volume compression test,the accurate discrete element simulation parameters were obtained,based on this,the discrete element method(DEM) was adopted to reveal the evolution law of the NGM granules movement in the sample shear process from the microscopic view.Based on the DEM,the influence of granule diameter,surface friction coefficient,normal pressure and shear velocity on the internal friction coefficient of the granular system were studied.And the parameters were conducted to be dimensionless by introducing the inertia coefficient.Finally,the expression showing power-law relationship of inertia coefficient,surface friction coefficient and internal friction coefficient is obtained.
文摘Recently, the incidence of<span> </span><i><span>Candida</span></i><span> infections has substantially increased. Conventional identification methods for </span><i><span>Candida</span></i><span> species are technically difficult to conduct and cannot accurately distinguish each species. The purpose of the present study was to design primers to identify and detect simultaneously</span><span> </span><span>eight medically important </span><i><span>Candida</span></i><span> species using one-step multiplex PCR. PCR primers were designed based on partial sequences of intergenic spacer (IGS) and internal transcribed spacer (ITS) genes of eight medically important </span><i><span>Candida</span></i><span> species. These primers were able to distinguish each </span><i><span>Candida</span></i><span> species and did not display cross-reactivity with representative </span><i><span>Candida </span></i><span>species other than the eight</span><i><span> Candida</span></i><span> species. Moreover, our developed one-step multiplex PCR method is accurate, specific, cost-effective, time-saving, and worked without requiring DNA extraction.</span>
基金Project(50575143)supported by the National Natural Science Foundation of ChinaProject(20040248005)supported by the Specialized Research Fund for the Doctoral Program of Higher Education of China
文摘The bulk metal forming processes were simulated by using a one-step finite element(FE)approach based on deformation theory of plasticity,which enables rapid prediction of final workpiece configurations and stress/strain distributions.This approach was implemented to minimize the approximated plastic potential energy derived from the total plastic work and the equivalent external work in static equilibrium,for incompressibly rigid-plastic materials,by FE calculation based on the extremum work principle.The one-step forward simulations of compression and rolling processes were presented as examples,and the results were compared with those obtained by classical incremental FE simulation to verify the feasibility and validity of the proposed method.
基金Natural Science Foundation of Hunan province(2022JJ30453 and 2024JJ6362)the Key Research and Development Program of Hunan Province(2022SK2014).
文摘Objective To facilitate the quality evaluation suitable for the unique characteristics of Chinese materia medica(CMM)by developing and implementing a novel approach known as the matching frequency statistical moment(MFSM)method.Methods This study established the MFSM method.To demonstrate its effectiveness,we applied this novel approach to analyze Danxi Granules(丹膝颗粒,DXG)and its constituent herbal materials.To begin with,the ultra-performance liquid chromatography(UPLC)was applied to obtain the chromatographic fingerprints of DXG and its constituent herbal materi-als.Next,the MFSM was leveraged to compress and integrate them into a new fingerprint with fewer analytical units.Then,we characterized the properties and variability of both the original and integrated fingerprints by calculating total quantum statistical moment(TQSM)parameters,information entropy and information amount,along with their relative standard deviation(RSD).Finally,we compared the TQSM parameters,information entropy and infor-mation amount,and their RSD between the traditional and novel fingerprints to validate the new analytical method.Results The chromatographic peaks of DXG and its 12 raw herbal materials were divided and integrated into peak families by the MFSM method.Before integration,the ranges of the peak number,three TQSM parameters,information entropy and information amount for each peak or peak family of UPLC fingerprints of DXG and its 12 raw herbal materials were 95.07−209.73,9390−183064μv·s,5.928−21.33 min,22.62−106.69 min^(2),4.230−6.539,and 50530−974186μv·s,respectively.After integration,the ranges of these parameters were 10.00−88.00,9390−183064μv·s,5.951−22.02 min,22.27−104.73 min^(2),2.223−5.277,and 38159−807200μv·s,respectively.Correspondingly,the RSD of all the aforementioned pa-rameters before integration were 2.12%−9.15%,6.04%−49.78%,1.15%−23.10%,3.97%−25.79%,1.49%−19.86%,and 6.64%−51.20%,respectively.However,after integration,they changed to 0.00%,6.04%−49.87%,1.73%−23.02%,3.84%−26.85%,1.17%−16.54%,and 6.40%−48.59%,respectively.The results demonstrated that in the newly integrated fingerprint,the analytical units of constituent herbal materials,information entropy and information amount were significantly reduced(P<0.05),while the TQSM parameters remained unchanged(P>0.05).Additionally,the RSD of the TQSM parameters,information entropy,and information amount didn’t show significant difference before and after integration(P>0.05),but the RSD of the number and area of the integrated analytical units significantly decreased(P<0.05).Conclusion The MFSM method could reduce the analytical units of constituent herbal mate-rials while maintain the properties and variability from their original fingerprint.Thus,it could serve as a feasible and reliable tool to reduce difficulties in analyzing multi-compo-nents within CMMs and facilitating the evaluation of their quality.
基金Item Sponsored by National Natural Science Foundation of China (50575134 ,50835002,50975174)
文摘For the traditional one-step formulations of using shell elements, the computations of the curvature variation and bending stiffness matrix were simplified by omitting the rotational DOFs （degrees of freedom） on the basis of initial flat blank and fully known final configuration. They were highly efficient but not suitable either for the forming processes with non-flat initial configurations or for one-step forward and multistep analyses. Thus, a one-step formulation based on the rotation-free BST （Basic Shell Triangle） element was presented. In this formulation, the penalty method was adopted to deal with contacts in the forming processes.
