The ideal motion characteristics for the vibrating screen was presented according to the principle of screening process with constant bed thickness.A new vibrating screen with variable elliptical trace was proposed.An...The ideal motion characteristics for the vibrating screen was presented according to the principle of screening process with constant bed thickness.A new vibrating screen with variable elliptical trace was proposed.An accurate mechanical model was constructed according to the required structural motion features.Applying multi-degree-of-freedom vibration theory,characteristics of the vibrating screen was analyzed.Kinematics parameters of the vibrating screen which motion traces were linear,circular or elliptical were obtained.The stable solutions of the dynamic equations gave the motions of the vibrating screen by means of computer simulations.Technological parameters,including amplitude,movement velocity and throwing index,of five specific points along the screen surface were gained by theoretical calculation.The results show that the traces of the new designed vibrating screen follow the ideal screening motion.The screening efficiency and processing capacity may thus be effectively improved.展开更多
Dynamic response of the screen mesh is of great significance in the optimum vibrating screen design.In this paper,based on the DEM-FEM co-simulation method,the effect of screening parameters on the dynamic response of...Dynamic response of the screen mesh is of great significance in the optimum vibrating screen design.In this paper,based on the DEM-FEM co-simulation method,the effect of screening parameters on the dynamic response of the screen mesh is explored and the mechanism is revealed on the particle level.Firstly,a virtual experiment on a linear vibrating screen was carried out to analyze the screening pa-rameters'effect with both impact load and sustained stress inflicted on the screen mesh.Then,the time-domain evolution regularity of the screen mesh LVA(Local Vibration Amplitude)under different particle plugging conditions was investigated based on the co-simulation.Finally,the influence of screening parameters on LVA and its distribution was discussed.The results show that the screening parameters can greatly affect the screen mesh LVA and its distribution by changing the movement of the granular material and the particle penetration probability,which provides an important basis for the optimal design of the screen mesh and its supporting structure.展开更多
苹果黄蚜(Aphis citricola van der Goot)和金纹细蛾(Lithocolletis ringoniella Matsumura)是危害较严重的两种果树害虫,且化学防治导致“3R”问题日益突出。为探索安全有效的生物源农药绿色防治技术,通过田间调查和防治试验,在陕西省...苹果黄蚜(Aphis citricola van der Goot)和金纹细蛾(Lithocolletis ringoniella Matsumura)是危害较严重的两种果树害虫,且化学防治导致“3R”问题日益突出。为探索安全有效的生物源农药绿色防治技术,通过田间调查和防治试验,在陕西省白水县和乾县苹果园进行两种害虫动态监测及生物源药剂筛选。结果表明:苹果黄蚜1 a中的大发生时期在5-6月,百梢虫量最高达1552头,建议药剂防治的最佳时期为5月上中旬。金纹细蛾幼虫发生高峰期分别为7月上旬、8月下旬和11月中旬,百叶虫斑数最高达17个。金纹细蛾成虫1 a发生4代,分别为4月下旬、6月中下旬、7月下旬至8月上旬和9月下旬,第3代危害最严重,单个诱捕器诱虫量最高达1344头。4月下旬是金纹细蛾越冬代成虫羽化的盛期,是应用性诱剂诱杀防治的关键时期;而6月中下旬是进行药剂防治的最佳时期。生物源农药22.4%螺虫乙酯悬浮剂对苹果黄蚜的防治效果较好,药后7 d防效仍在80%以上,1.8%阿维菌素微乳剂、0.3%印楝素乳油、6%鱼藤酮乳油也有较好防效。0.3%印楝素乳油对金纹细蛾持效性长,药后15 d防效仍达81.25%,1.8%阿维菌素乳油和2.2%甲维·氟铃脲乳油药后15 d防效也在70%以上。展开更多
HIV- 1 RT is an important target for the treatment of AIDS. There are two major classes of antiviral agents that inhibit HIV- 1 RT have been identified, nucleoside RT inhibitors （NRTIs） and non-nucleoside RT inhibit...HIV- 1 RT is an important target for the treatment of AIDS. There are two major classes of antiviral agents that inhibit HIV- 1 RT have been identified, nucleoside RT inhibitors （NRTIs） and non-nucleoside RT inhibitors （NNRTIs）. In this report, a noval class of non-nucleoside compound with potential RT inhibitory activity were found from the traditional Chinese medicines database （TCMD） using a combination of virtual screening, docking, molecular dynamic simulations, where results were ranked by scoring function of the docking tool. The result indicates that M4753 （a compound derived from TCMD） has not only the lowest bonding energy but also the best match in geometric conformation with the forthcoming NNRTIs. Accordingly M4753 might possibly become a promising lead compound of NNRTIs for AIDS therapy.展开更多
The exciting condition of acoustic plasmons and their dynamic screening effect on the interaction potential between charged particles are discussed.The results of some metals with two outermost bands not fully filled ...The exciting condition of acoustic plasmons and their dynamic screening effect on the interaction potential between charged particles are discussed.The results of some metals with two outermost bands not fully filled are given and the effect on the D-D fusion reaction rate in palladium is evaluated.展开更多
We present our theoretical investigations on the effects of disorder on the electron-phonon interaction in semiconducting GaAs system. Both the temperature (T) and disorder (electron mean free path l) dependences of t...We present our theoretical investigations on the effects of disorder on the electron-phonon interaction in semiconducting GaAs system. Both the temperature (T) and disorder (electron mean free path l) dependences of the electron-phonon scattering rate have been determined. On consideration of the dynamic screening, we find a significant change in the temperature exponent as well as the pre factor from the earlier reported temperature power law dependence result ?T6 obtained under static screening. Also the dynamic screening makes a noticeable change in the character of the dependence of scattering rate on the mean free path from the static screening result.展开更多
The papain-like protease(PLpro)is vital for the replication of coronaviruses(Co Vs),as well as for escaping innate-immune responses of the host.Hence,it has emerged as an attractive antiviral drug-target.In this study...The papain-like protease(PLpro)is vital for the replication of coronaviruses(Co Vs),as well as for escaping innate-immune responses of the host.Hence,it has emerged as an attractive antiviral drug-target.In this study,computational approaches were employed,mainly the structure-based virtual screening coupled with all-atom molecular dynamics(MD)simulations to computationally identify specific inhibitors of severe acute respiratory syndrome coronavirus 2(SARS-Co V-2)PLpro,which can be further developed as potential pan-PLprobased broad-spectrum antiviral drugs.The sequence,structure,and functional conserveness of most deadly human Co Vs PLprowere explored,and it was revealed that functionally important catalytic triad residues are well conserved among SARS-Co V,SARS-Co V-2,and middle east respiratory syndrome coronavirus(MERS-Co V).The subsequent screening of a focused protease inhibitors database composed of^7,000 compounds resulted in the identification of three candidate compounds,ADM13083841,LMG15521745,and SYN15517940.These three compounds established conserved interactions which were further explored through MD simulations,free energy calculations,and residual energy contribution estimated by MM-PB(GB)SA method.All these compounds showed stable conformation and interacted well with the active residues of SARS-Co V-2 PLpro,and showed consistent interaction profile with SARS-Co V PLproand MERS-Co V PLproas well.Conclusively,the reported SARS-Co V-2 PLprospecific compounds could serve as seeds for developing potent pan-PLprobased broad-spectrum antiviral drugs against deadly human coronaviruses.Moreover,the presented information related to binding site residual energy contribution could lead to further optimization of these compounds.展开更多
基金Projects 50574091 and 50774084 supported by the National Natural Science Foundation of China
文摘The ideal motion characteristics for the vibrating screen was presented according to the principle of screening process with constant bed thickness.A new vibrating screen with variable elliptical trace was proposed.An accurate mechanical model was constructed according to the required structural motion features.Applying multi-degree-of-freedom vibration theory,characteristics of the vibrating screen was analyzed.Kinematics parameters of the vibrating screen which motion traces were linear,circular or elliptical were obtained.The stable solutions of the dynamic equations gave the motions of the vibrating screen by means of computer simulations.Technological parameters,including amplitude,movement velocity and throwing index,of five specific points along the screen surface were gained by theoretical calculation.The results show that the traces of the new designed vibrating screen follow the ideal screening motion.The screening efficiency and processing capacity may thus be effectively improved.
基金supported by the Unveils Major Projects of Hubei Province (grant No.2019AEE015).
文摘Dynamic response of the screen mesh is of great significance in the optimum vibrating screen design.In this paper,based on the DEM-FEM co-simulation method,the effect of screening parameters on the dynamic response of the screen mesh is explored and the mechanism is revealed on the particle level.Firstly,a virtual experiment on a linear vibrating screen was carried out to analyze the screening pa-rameters'effect with both impact load and sustained stress inflicted on the screen mesh.Then,the time-domain evolution regularity of the screen mesh LVA(Local Vibration Amplitude)under different particle plugging conditions was investigated based on the co-simulation.Finally,the influence of screening parameters on LVA and its distribution was discussed.The results show that the screening parameters can greatly affect the screen mesh LVA and its distribution by changing the movement of the granular material and the particle penetration probability,which provides an important basis for the optimal design of the screen mesh and its supporting structure.
基金supported by the grants from Chinese National Science Foundation(No.30472166)the Tianjin Commission of Sciences and Technology under the Contract(No.06YFGZSH07000)
文摘HIV- 1 RT is an important target for the treatment of AIDS. There are two major classes of antiviral agents that inhibit HIV- 1 RT have been identified, nucleoside RT inhibitors （NRTIs） and non-nucleoside RT inhibitors （NNRTIs）. In this report, a noval class of non-nucleoside compound with potential RT inhibitory activity were found from the traditional Chinese medicines database （TCMD） using a combination of virtual screening, docking, molecular dynamic simulations, where results were ranked by scoring function of the docking tool. The result indicates that M4753 （a compound derived from TCMD） has not only the lowest bonding energy but also the best match in geometric conformation with the forthcoming NNRTIs. Accordingly M4753 might possibly become a promising lead compound of NNRTIs for AIDS therapy.
基金Project supported by the National Natural Science Foundation of ChinaLFTZ-1298 CAS
文摘The exciting condition of acoustic plasmons and their dynamic screening effect on the interaction potential between charged particles are discussed.The results of some metals with two outermost bands not fully filled are given and the effect on the D-D fusion reaction rate in palladium is evaluated.
文摘We present our theoretical investigations on the effects of disorder on the electron-phonon interaction in semiconducting GaAs system. Both the temperature (T) and disorder (electron mean free path l) dependences of the electron-phonon scattering rate have been determined. On consideration of the dynamic screening, we find a significant change in the temperature exponent as well as the pre factor from the earlier reported temperature power law dependence result ?T6 obtained under static screening. Also the dynamic screening makes a noticeable change in the character of the dependence of scattering rate on the mean free path from the static screening result.
基金the Starting Research Grant for High-level Talents from Guangxi Universitythe Postdoctoral Project from Guangxi University。
文摘The papain-like protease(PLpro)is vital for the replication of coronaviruses(Co Vs),as well as for escaping innate-immune responses of the host.Hence,it has emerged as an attractive antiviral drug-target.In this study,computational approaches were employed,mainly the structure-based virtual screening coupled with all-atom molecular dynamics(MD)simulations to computationally identify specific inhibitors of severe acute respiratory syndrome coronavirus 2(SARS-Co V-2)PLpro,which can be further developed as potential pan-PLprobased broad-spectrum antiviral drugs.The sequence,structure,and functional conserveness of most deadly human Co Vs PLprowere explored,and it was revealed that functionally important catalytic triad residues are well conserved among SARS-Co V,SARS-Co V-2,and middle east respiratory syndrome coronavirus(MERS-Co V).The subsequent screening of a focused protease inhibitors database composed of^7,000 compounds resulted in the identification of three candidate compounds,ADM13083841,LMG15521745,and SYN15517940.These three compounds established conserved interactions which were further explored through MD simulations,free energy calculations,and residual energy contribution estimated by MM-PB(GB)SA method.All these compounds showed stable conformation and interacted well with the active residues of SARS-Co V-2 PLpro,and showed consistent interaction profile with SARS-Co V PLproand MERS-Co V PLproas well.Conclusively,the reported SARS-Co V-2 PLprospecific compounds could serve as seeds for developing potent pan-PLprobased broad-spectrum antiviral drugs against deadly human coronaviruses.Moreover,the presented information related to binding site residual energy contribution could lead to further optimization of these compounds.
