OBJECTIVE To explore the mechanism of action of Qihuang Zhuyu formula(QHZYF)in improving depression after myocardial infarction(MI),with a focus on revealing its regulatory effect on the inflammatory response of the h...OBJECTIVE To explore the mechanism of action of Qihuang Zhuyu formula(QHZYF)in improving depression after myocardial infarction(MI),with a focus on revealing its regulatory effect on the inflammatory response of the heart and brain.METHODS The active ingredients of QHZYF and the action targets for intervening in depression after MI were analyzed by using ultra-performance liquid chromatography-high-resolution mass spectrometry(UPLC-Q-TOF/MS)combined with network pharmacology and molecular docking.A rat model of depression after MI was established by ligation of the left anterior descending coronary artery combined with chronic restraint stress.Echocardiography was used to evaluate cardiac function,hematoxylin-eosin(HE)and Masson staining were used to evaluate myocardial injury,behavioral tests were used to detect melancholic behaviors,Nissl staining was used to evaluate hippocampal neuron injury.Western blot detection of tumor necrosis factor receptor 2(TNFR2),phosphatidylinositol-3-kinase(PI3K),phosphorylated seronine protein kinase(p-AKT),seronine protein kinase(AKT),tumor necrosis factor receptor 1(TNFR1),phosphorylated nuclear factorκB(p-NF-κB),and nuclear factorκB(NF-κB)in cardiac and hippocampal tissues was conducted.The levels of serum IL-6 and IL-10 were detected by enzyme-linked immunosorbent assay(ELISA),and the expression of TNFR1 and TNFR2 was detected by immunohistochemical technique(IHC).In vitro experiments,co-culture of rat cardiomyocyte line H9C2 cells and rat adrenal pheochromocytoma cell line with high differentiation PC12 cells was conducted,TNFR1 inhibitor(H398)and TNFR2 agonist(C-6His)were administered for intervention,and the expression of TNFR2,PI3K,p-AKT,AKT,TNFR1,NF-κB,p-NF-κB was detected by Western blot.Observe the apoptosis of cells by TUNEL staining,ELISA was used to detect the levels of IL-6 and IL-10 in the cell supernatant.RESULTS Network pharmacological analysis indicates that the TNF signaling pathway was a key target for the treatment of depression after MI with the QHZYF.In vivo experiments have confirmed that the intervention of QHZYF could significantly improve the cardiac function,myocardial tissue and hippocampal neuron structure damage of depressed rats after MI,and improve their depression-like behaviors.At the molecular level,the high-dose group of QHZYF significantly upregulated TNFR2,p-AKT/AKT,and IL-10 in cardiac and hippocampal tissues(P<0.01),and downregulated TNFR1,p-NF-κB/NF-κB and IL-6(P<0.01).In vitro experiments showed that the drug-containing serum of QHZYF significantly upregulated the expression of TNFR2,p-AKT/AKT and IL-10 in H9C2 and PC12 cells(P<0.01),downregulated the expression of TNFR1,p-NF-κB/NF-κB and IL-6(P<0.01),and significantly inhibited cell apoptosis(P<0.01).Furthermore,experiments on the combined application of H398 or C-6His further confirmed that its protective and anti-inflammatory effects were mediated by regulating the TNFR2/PI3K/AKT and TNFR1/NF-κB pathways.CONCLUSION QHZYF improves the homeostasis of heart and brain inflammation by regulating the TNF pathway,and ameliorates myocardial injury and depressive state in depressed rats after MI.展开更多
To investigate the applicability of four commonly used color difference formulas(CIELAB,CIE94,CMC(1:1),and CIEDE2000)in the printing field on 3D objects,as well as the impact of four standard light sources(D65,D50,A,a...To investigate the applicability of four commonly used color difference formulas(CIELAB,CIE94,CMC(1:1),and CIEDE2000)in the printing field on 3D objects,as well as the impact of four standard light sources(D65,D50,A,and TL84)on 3D color difference evaluations,50 glossy spheres with a diameter of 2cm based on the Sailner J4003D color printing device were created.These spheres were centered around the five recommended colors(gray,red,yellow,green,and blue)by CIE.Color difference was calculated according to the four formulas,and 111 pairs of experimental samples meeting the CIELAB gray scale color difference requirements(1.0-14.0)were selected.Ten observers,aged between 22 and 27 with normal color vision,were participated in this study,using the gray scale method from psychophysical experiments to conduct color difference evaluations under the four light sources,with repeated experiments for each observer.The results indicated that the overall effect of the D65 light source on 3D objects color difference was minimal.In contrast,D50 and A light sources had a significant impact within the small color difference range,while the TL84 light source influenced both large and small color difference considerably.Among the four color difference formulas,CIEDE2000 demonstrated the best predictive performance for color difference in 3D objects,followed by CMC(1:1),CIE94,and CIELAB.展开更多
Most of the existing studies on tunnel blast wave are based on spherical or grouped charges, however,conventional weapons are mostly cylindrical rather than spherical. In order to analyze the impact of cylindrical cha...Most of the existing studies on tunnel blast wave are based on spherical or grouped charges, however,conventional weapons are mostly cylindrical rather than spherical. In order to analyze the impact of cylindrical charges on the tunnel blast wave loads and to develop a quantitative calculation method, this study carried out experimental and numerical research. Initially, external explosion experiments were conducted using both 35 kg spherical charges and cylindrical charges with aspect ratio of 4.8 at two different distances from the tunnel entrance. Comparative analysis of the blast wave parameters in the tunnel revealed that the explosive equivalent of the cylindrical charges was significantly higher than that of the spherical charges. To address this, an equivalent coefficient κ based on the spherical charges was proposed for the cylindrical charges. Subsequently, numerical simulations were conducted for the experimental conditions, and the numerical simulation results match the experiments well. Through numerical calculations, the reliability of the equivalent coefficient κ under the experimental conditions was verified, and comparison analysis indicated that the explosion energy of cylindrical charges spreads more radially, resulting in more explosion energy entering the tunnel, which is the fundamental reason for the increase in tunnel blast wave loads. Additionally, analyzing the explosion energy ratio entering the tunnel is an effective method for calculating the equivalent coefficient κ. Finally, through more than one hundred sets of numerical calculation results, the impact of the proportional distance λ and the ratio of charge mass to the tunnel cross-section dimension φ on the equivalence coefficients κ was investigated. An empirical formula for the equivalence coefficient κ was derived through fitting, and the accuracy of the formula was validated through literature experimental results. The research findings of this paper will provide valuable guidance for the calculation of blast wave loads in tunnel.展开更多
Praising or compliment is a communicative behavior shared by people of different languages. However, due to the influence of unique culture and different society, the language of compliment differs greatly. The author...Praising or compliment is a communicative behavior shared by people of different languages. However, due to the influence of unique culture and different society, the language of compliment differs greatly. The author of this essay is trying to analyze the formula of English compliment shared by all the English speaking nations, esp. in the United States.展开更多
Mortality is normal and natural in aquaculture experiments. However, it becomes a problem when measuring feed intake as a component of nutrient utilization parameters such as： feed conversion ratio, feed conversion e...Mortality is normal and natural in aquaculture experiments. However, it becomes a problem when measuring feed intake as a component of nutrient utilization parameters such as： feed conversion ratio, feed conversion efficiency, apparent net protein utilization, protein efficiency ratio and protein productive value. In order to accurately evaluate feed intake with due consideration of mortality encountered, a formulae was developed using empirical data obtained from an experiement that had mortality. The formulae Fwas： total feed consumed by numbers of survived fishes=DL∑i=1n（Fi/Ni）N. Where, D=Numbers of days fishes were fed within each period ibefore it was adjusted（e.g fortnight）, it was constant throught period of experiment; F=Uantity of feed fed per day for a fortnight before the quantity was adjusted, it changed every fortnight; L=Numbers of living fishes at the end of experimental period; N=Numbers of fishes at each weighing period, it might change every fortnight or might be constant if no mortality occurred; while n=Numbers of times fishes were weighed and quantity of feed was adjusted but this did not include the final weighing at the termination of experiment. However, if the fishes were weighed weekly, then D=6.展开更多
The prediction of the fragment velocity distribution of a cylindrical cased charge with end caps is one of the key issues to assess the damage efficiency of the warhead. However, limited work has been conducted to pre...The prediction of the fragment velocity distribution of a cylindrical cased charge with end caps is one of the key issues to assess the damage efficiency of the warhead. However, limited work has been conducted to predict the fragment velocity distributions along the axis of cylindrical cased charges with end caps. This paper presents a study of the velocity distribution of fragments caused by the explosion of a cylindrical cased charge with end caps. The fragment velocity distribution and the end cap velocity were determined by an X-ray radiography method, and the axial fragment distribution was determined by witness plates. It was found that the velocities of fragments, especially near the edge, were increased when the end caps were added, and the position of maximum velocity is closer to the non-detonation end. The fragment velocities were increased, and the fragment projection range was decreased with the increase of the thickness of the end cap. A formula for fragment velocity distributions of a cylindrical cased charge with end caps, which is based on Huang’s formula, was proposed by the theoretical analysis and data fitting and validated experimentally. The results indicate that the proposed formula is accurate in predicting the fragment velocity distribution along the axis of a cylindrical cased charge with end caps detonated at one end.展开更多
Kinematics and dynamics analyses were performed for a spatial 3-revolute joint-revolute joint-clylindric pair(3-RRC) parallel manipulator.This 3-RRC parallel manipulator is composed of a moving platform,a base platfor...Kinematics and dynamics analyses were performed for a spatial 3-revolute joint-revolute joint-clylindric pair(3-RRC) parallel manipulator.This 3-RRC parallel manipulator is composed of a moving platform,a base platform,and three revolute joint-revolute joint-column pair chains which connect the moving platform and the base platform.Firstly,kinematics analysis for 3-RRC parallel manipulator was conducted.Next,on the basis of Lagrange formula,a simply-structured dynamic model of 3-RRC parallel manipulator was derived.Finally,through a calculation example,the variation of motorial parameters of this 3-RRC parallel manipulator,equivalent moment of inertia,driving force/torque and energy consumption was discussed.The research findings have important significance for research and engineering projects such as analyzing dynamic features,mechanism optimization design and control of 3-RRC parallel manipulator.展开更多
Non-cylindrical casings filled with explosives have undergone rapid development in warhead design and explosion control.The fragment spatial distribution of prismatic casings is more complex than that of traditional c...Non-cylindrical casings filled with explosives have undergone rapid development in warhead design and explosion control.The fragment spatial distribution of prismatic casings is more complex than that of traditional cylindrical casings.In this study,numerical and experimental investigations into the fragment spatial distribution of a prismatic casing were conducted.A new numerical method,which adds the Lagrangian marker points to the Eulerian grid,was proposed to track the multi-material interfaces and material dynamic fractures.Physical quantity mappings between the Lagrangian marker points and Eulerian grid were achieved by their topological relationship.Thereafter,the fragment spatial distributions of the prismatic casing with different fragment sizes,fragment shapes,and casing geometries were obtained using the numerical method.Moreover,fragment spatial distribution experiments were conducted on the prismatic casing with different fragment sizes and shapes,and the experimental data were compared with the numerical results.The effects of the fragment and casing geometry on the fragment spatial distributions were determined by analyzing the numerical results and experimental data.Finally,a formula including the casing geometry parameters was fitted to predict the fragment spatial distribution of the prismatic casing under internal explosive loading.展开更多
Existing analytical methods of buried steel pipelines subjected to active strike-slip faults depended on a number of simplifications.To study the failure mechanism more accurately,a refined strain analytical methodolo...Existing analytical methods of buried steel pipelines subjected to active strike-slip faults depended on a number of simplifications.To study the failure mechanism more accurately,a refined strain analytical methodology was proposed,taking the nonlinear characteristics of soil-pipeline interaction and pipe steel into account.Based on the elastic-beam and beam-on-elastic-foundation theories,the position of pipe potential destruction and the strain and deformation distributions along the pipeline were derived.Compared with existing analytical methods and three-dimensional nonlinear finite element analysis,the maximum axial total strains of pipe from the analytical methodology presented are in good agreement with the finite element results at small and intermediate fault movements and become gradually more conservative at large fault displacements.The position of pipe potential failure and the deformation distribution along the pipeline are fairly consistent with the finite element results.展开更多
A method is proposed to deal with the uncertain multiple attribute group decision making problems,where 2-dimension uncertain linguistic variables(2DULVs)are used as the reliable way for the experts to express their f...A method is proposed to deal with the uncertain multiple attribute group decision making problems,where 2-dimension uncertain linguistic variables(2DULVs)are used as the reliable way for the experts to express their fuzzy subjective evaluation information.Firstly,in order to measure the 2DULVs more accurately,a new method is proposed to compare two 2DULVs,called a score function,while a new function is defined to measure the distance between two 2DULVs.Secondly,two optimization models are established to determine the weight of experts and attributes based on the new distance formula and a weighted average operator is used to determine the comprehensive evaluation value of each alternative.Then,a score function is used to determine the ranking of the alternatives.Finally,the effectiveness of the proposed method is proved by an illustrated example.展开更多
OBJECTIVE Depression is one of the prevalent and prominent complex psychiatric diseases and the number of depressed patients has been on the rise globally during the recent decades.Xiaoyaosan,as a famous Chinese herba...OBJECTIVE Depression is one of the prevalent and prominent complex psychiatric diseases and the number of depressed patients has been on the rise globally during the recent decades.Xiaoyaosan,as a famous Chinese herbal formula,has been widely used in depression patients for a long time. However,the therapeutic mechanisms remain uncertain because of difficulty of depression pathophysiology and the lack of bioinformatic approach to understand the molecular connection. METHODS In this thesis,we applied a network pharmacology approach to explain the potential mechanisms between Xiaoyaosan and depression involved in oral bioavailability screening,drug-likeness assessment,caco-2 permeability,blood-brain barrier target recognition and network analysis. RESULTS 66 active compounds in Xiaoyaosan formula with favorable pharmacokinetic profiles are predicted as active compounds for anti-depression treatment. Network analyses show that these 66 compounds target 40depression-associated proteins including especially HTR2A,NR 3C1,MAOB,XDH and CNR2. These proteins are mainly involved in the neuroactive ligand-receptor interaction,serotonergic synapse,cAMP signaling pathways and calcium signaling pathways. CONCLUSION The integrated network pharmacology method is an effective approach to illustrate the anti-depression mechanisms of herbs,and this in silico approach can be applied in drug discovery.展开更多
The double casing warhead with sandwiched charge is a novel fragmentation warhead that can produce two groups of fragments with different velocity,and the previous work has presented a calculation formula to determine...The double casing warhead with sandwiched charge is a novel fragmentation warhead that can produce two groups of fragments with different velocity,and the previous work has presented a calculation formula to determine the maximum fragment velocity.The current work builds on the published formula to further develop a formula for calculating the axial distribution characteristics of the fragment velocity.For this type of warhead,the simulation of the dispersion characteristics of the detonation products at different positions shows that the detonation products at the ends have a much larger axial velocity than those in the middle,and the detonation products have a greater axial dispersion velocity when they are closer to the central axis.The loading process and the fragment velocity vary with the axial position for both casing layers,and the total velocity of the fragments is the vector sum of the radial velocity and the axial velocity.At the same axial position,the acceleration time of the inner casing is greater than that of the outer casing.For the same casing,the fragments generated at the ends have a longer acceleration time than the fragments from the middle.The proposed formula is validated with the X-ray radiography results of the four warheads previously tested experimentally and the 3D smoothedparticle hydrodynamics numerical simulation results of several series of new warheads with different configurations.The formula can accurately and reliably calculate the fragment velocity when the lengthto-diameter ratio of the charge is greater than 1.5 and the thickness of the casing is less than 20%its inner radius.This work thus provides a key reference for the theoretical analysis and the design of warheads with multiple casings.展开更多
文摘OBJECTIVE To explore the mechanism of action of Qihuang Zhuyu formula(QHZYF)in improving depression after myocardial infarction(MI),with a focus on revealing its regulatory effect on the inflammatory response of the heart and brain.METHODS The active ingredients of QHZYF and the action targets for intervening in depression after MI were analyzed by using ultra-performance liquid chromatography-high-resolution mass spectrometry(UPLC-Q-TOF/MS)combined with network pharmacology and molecular docking.A rat model of depression after MI was established by ligation of the left anterior descending coronary artery combined with chronic restraint stress.Echocardiography was used to evaluate cardiac function,hematoxylin-eosin(HE)and Masson staining were used to evaluate myocardial injury,behavioral tests were used to detect melancholic behaviors,Nissl staining was used to evaluate hippocampal neuron injury.Western blot detection of tumor necrosis factor receptor 2(TNFR2),phosphatidylinositol-3-kinase(PI3K),phosphorylated seronine protein kinase(p-AKT),seronine protein kinase(AKT),tumor necrosis factor receptor 1(TNFR1),phosphorylated nuclear factorκB(p-NF-κB),and nuclear factorκB(NF-κB)in cardiac and hippocampal tissues was conducted.The levels of serum IL-6 and IL-10 were detected by enzyme-linked immunosorbent assay(ELISA),and the expression of TNFR1 and TNFR2 was detected by immunohistochemical technique(IHC).In vitro experiments,co-culture of rat cardiomyocyte line H9C2 cells and rat adrenal pheochromocytoma cell line with high differentiation PC12 cells was conducted,TNFR1 inhibitor(H398)and TNFR2 agonist(C-6His)were administered for intervention,and the expression of TNFR2,PI3K,p-AKT,AKT,TNFR1,NF-κB,p-NF-κB was detected by Western blot.Observe the apoptosis of cells by TUNEL staining,ELISA was used to detect the levels of IL-6 and IL-10 in the cell supernatant.RESULTS Network pharmacological analysis indicates that the TNF signaling pathway was a key target for the treatment of depression after MI with the QHZYF.In vivo experiments have confirmed that the intervention of QHZYF could significantly improve the cardiac function,myocardial tissue and hippocampal neuron structure damage of depressed rats after MI,and improve their depression-like behaviors.At the molecular level,the high-dose group of QHZYF significantly upregulated TNFR2,p-AKT/AKT,and IL-10 in cardiac and hippocampal tissues(P<0.01),and downregulated TNFR1,p-NF-κB/NF-κB and IL-6(P<0.01).In vitro experiments showed that the drug-containing serum of QHZYF significantly upregulated the expression of TNFR2,p-AKT/AKT and IL-10 in H9C2 and PC12 cells(P<0.01),downregulated the expression of TNFR1,p-NF-κB/NF-κB and IL-6(P<0.01),and significantly inhibited cell apoptosis(P<0.01).Furthermore,experiments on the combined application of H398 or C-6His further confirmed that its protective and anti-inflammatory effects were mediated by regulating the TNFR2/PI3K/AKT and TNFR1/NF-κB pathways.CONCLUSION QHZYF improves the homeostasis of heart and brain inflammation by regulating the TNF pathway,and ameliorates myocardial injury and depressive state in depressed rats after MI.
文摘To investigate the applicability of four commonly used color difference formulas(CIELAB,CIE94,CMC(1:1),and CIEDE2000)in the printing field on 3D objects,as well as the impact of four standard light sources(D65,D50,A,and TL84)on 3D color difference evaluations,50 glossy spheres with a diameter of 2cm based on the Sailner J4003D color printing device were created.These spheres were centered around the five recommended colors(gray,red,yellow,green,and blue)by CIE.Color difference was calculated according to the four formulas,and 111 pairs of experimental samples meeting the CIELAB gray scale color difference requirements(1.0-14.0)were selected.Ten observers,aged between 22 and 27 with normal color vision,were participated in this study,using the gray scale method from psychophysical experiments to conduct color difference evaluations under the four light sources,with repeated experiments for each observer.The results indicated that the overall effect of the D65 light source on 3D objects color difference was minimal.In contrast,D50 and A light sources had a significant impact within the small color difference range,while the TL84 light source influenced both large and small color difference considerably.Among the four color difference formulas,CIEDE2000 demonstrated the best predictive performance for color difference in 3D objects,followed by CMC(1:1),CIE94,and CIELAB.
文摘Most of the existing studies on tunnel blast wave are based on spherical or grouped charges, however,conventional weapons are mostly cylindrical rather than spherical. In order to analyze the impact of cylindrical charges on the tunnel blast wave loads and to develop a quantitative calculation method, this study carried out experimental and numerical research. Initially, external explosion experiments were conducted using both 35 kg spherical charges and cylindrical charges with aspect ratio of 4.8 at two different distances from the tunnel entrance. Comparative analysis of the blast wave parameters in the tunnel revealed that the explosive equivalent of the cylindrical charges was significantly higher than that of the spherical charges. To address this, an equivalent coefficient κ based on the spherical charges was proposed for the cylindrical charges. Subsequently, numerical simulations were conducted for the experimental conditions, and the numerical simulation results match the experiments well. Through numerical calculations, the reliability of the equivalent coefficient κ under the experimental conditions was verified, and comparison analysis indicated that the explosion energy of cylindrical charges spreads more radially, resulting in more explosion energy entering the tunnel, which is the fundamental reason for the increase in tunnel blast wave loads. Additionally, analyzing the explosion energy ratio entering the tunnel is an effective method for calculating the equivalent coefficient κ. Finally, through more than one hundred sets of numerical calculation results, the impact of the proportional distance λ and the ratio of charge mass to the tunnel cross-section dimension φ on the equivalence coefficients κ was investigated. An empirical formula for the equivalence coefficient κ was derived through fitting, and the accuracy of the formula was validated through literature experimental results. The research findings of this paper will provide valuable guidance for the calculation of blast wave loads in tunnel.
文摘Praising or compliment is a communicative behavior shared by people of different languages. However, due to the influence of unique culture and different society, the language of compliment differs greatly. The author of this essay is trying to analyze the formula of English compliment shared by all the English speaking nations, esp. in the United States.
文摘Mortality is normal and natural in aquaculture experiments. However, it becomes a problem when measuring feed intake as a component of nutrient utilization parameters such as： feed conversion ratio, feed conversion efficiency, apparent net protein utilization, protein efficiency ratio and protein productive value. In order to accurately evaluate feed intake with due consideration of mortality encountered, a formulae was developed using empirical data obtained from an experiement that had mortality. The formulae Fwas： total feed consumed by numbers of survived fishes=DL∑i=1n（Fi/Ni）N. Where, D=Numbers of days fishes were fed within each period ibefore it was adjusted（e.g fortnight）, it was constant throught period of experiment; F=Uantity of feed fed per day for a fortnight before the quantity was adjusted, it changed every fortnight; L=Numbers of living fishes at the end of experimental period; N=Numbers of fishes at each weighing period, it might change every fortnight or might be constant if no mortality occurred; while n=Numbers of times fishes were weighed and quantity of feed was adjusted but this did not include the final weighing at the termination of experiment. However, if the fishes were weighed weekly, then D=6.
基金financial support from the exploratory project of State Key Laboratory of Explosion Science and Technology, China (No. QNKT19-09)。
文摘The prediction of the fragment velocity distribution of a cylindrical cased charge with end caps is one of the key issues to assess the damage efficiency of the warhead. However, limited work has been conducted to predict the fragment velocity distributions along the axis of cylindrical cased charges with end caps. This paper presents a study of the velocity distribution of fragments caused by the explosion of a cylindrical cased charge with end caps. The fragment velocity distribution and the end cap velocity were determined by an X-ray radiography method, and the axial fragment distribution was determined by witness plates. It was found that the velocities of fragments, especially near the edge, were increased when the end caps were added, and the position of maximum velocity is closer to the non-detonation end. The fragment velocities were increased, and the fragment projection range was decreased with the increase of the thickness of the end cap. A formula for fragment velocity distributions of a cylindrical cased charge with end caps, which is based on Huang’s formula, was proposed by the theoretical analysis and data fitting and validated experimentally. The results indicate that the proposed formula is accurate in predicting the fragment velocity distribution along the axis of a cylindrical cased charge with end caps detonated at one end.
基金Project(2014QNB18) supported by the Fundamental Research Funds for the Central Universities of ChinaProject(2014CBO46300) supported by the National Basic Research Program of China
文摘Kinematics and dynamics analyses were performed for a spatial 3-revolute joint-revolute joint-clylindric pair(3-RRC) parallel manipulator.This 3-RRC parallel manipulator is composed of a moving platform,a base platform,and three revolute joint-revolute joint-column pair chains which connect the moving platform and the base platform.Firstly,kinematics analysis for 3-RRC parallel manipulator was conducted.Next,on the basis of Lagrange formula,a simply-structured dynamic model of 3-RRC parallel manipulator was derived.Finally,through a calculation example,the variation of motorial parameters of this 3-RRC parallel manipulator,equivalent moment of inertia,driving force/torque and energy consumption was discussed.The research findings have important significance for research and engineering projects such as analyzing dynamic features,mechanism optimization design and control of 3-RRC parallel manipulator.
基金supported by the National Natural Science Foundation of China(Grant No.11822203and 11702026)。
文摘Non-cylindrical casings filled with explosives have undergone rapid development in warhead design and explosion control.The fragment spatial distribution of prismatic casings is more complex than that of traditional cylindrical casings.In this study,numerical and experimental investigations into the fragment spatial distribution of a prismatic casing were conducted.A new numerical method,which adds the Lagrangian marker points to the Eulerian grid,was proposed to track the multi-material interfaces and material dynamic fractures.Physical quantity mappings between the Lagrangian marker points and Eulerian grid were achieved by their topological relationship.Thereafter,the fragment spatial distributions of the prismatic casing with different fragment sizes,fragment shapes,and casing geometries were obtained using the numerical method.Moreover,fragment spatial distribution experiments were conducted on the prismatic casing with different fragment sizes and shapes,and the experimental data were compared with the numerical results.The effects of the fragment and casing geometry on the fragment spatial distributions were determined by analyzing the numerical results and experimental data.Finally,a formula including the casing geometry parameters was fitted to predict the fragment spatial distribution of the prismatic casing under internal explosive loading.
基金Project(50439010) supported by the National Natural Science Foundation of ChinaProject(DUT10ZD201) supported by the Fundamental Research Funds for the Central Universities in China
文摘Existing analytical methods of buried steel pipelines subjected to active strike-slip faults depended on a number of simplifications.To study the failure mechanism more accurately,a refined strain analytical methodology was proposed,taking the nonlinear characteristics of soil-pipeline interaction and pipe steel into account.Based on the elastic-beam and beam-on-elastic-foundation theories,the position of pipe potential destruction and the strain and deformation distributions along the pipeline were derived.Compared with existing analytical methods and three-dimensional nonlinear finite element analysis,the maximum axial total strains of pipe from the analytical methodology presented are in good agreement with the finite element results at small and intermediate fault movements and become gradually more conservative at large fault displacements.The position of pipe potential failure and the deformation distribution along the pipeline are fairly consistent with the finite element results.
基金This work was supported by the Natural Science Foundation of Liaoning Province(2013020022).
文摘A method is proposed to deal with the uncertain multiple attribute group decision making problems,where 2-dimension uncertain linguistic variables(2DULVs)are used as the reliable way for the experts to express their fuzzy subjective evaluation information.Firstly,in order to measure the 2DULVs more accurately,a new method is proposed to compare two 2DULVs,called a score function,while a new function is defined to measure the distance between two 2DULVs.Secondly,two optimization models are established to determine the weight of experts and attributes based on the new distance formula and a weighted average operator is used to determine the comprehensive evaluation value of each alternative.Then,a score function is used to determine the ranking of the alternatives.Finally,the effectiveness of the proposed method is proved by an illustrated example.
文摘OBJECTIVE Depression is one of the prevalent and prominent complex psychiatric diseases and the number of depressed patients has been on the rise globally during the recent decades.Xiaoyaosan,as a famous Chinese herbal formula,has been widely used in depression patients for a long time. However,the therapeutic mechanisms remain uncertain because of difficulty of depression pathophysiology and the lack of bioinformatic approach to understand the molecular connection. METHODS In this thesis,we applied a network pharmacology approach to explain the potential mechanisms between Xiaoyaosan and depression involved in oral bioavailability screening,drug-likeness assessment,caco-2 permeability,blood-brain barrier target recognition and network analysis. RESULTS 66 active compounds in Xiaoyaosan formula with favorable pharmacokinetic profiles are predicted as active compounds for anti-depression treatment. Network analyses show that these 66 compounds target 40depression-associated proteins including especially HTR2A,NR 3C1,MAOB,XDH and CNR2. These proteins are mainly involved in the neuroactive ligand-receptor interaction,serotonergic synapse,cAMP signaling pathways and calcium signaling pathways. CONCLUSION The integrated network pharmacology method is an effective approach to illustrate the anti-depression mechanisms of herbs,and this in silico approach can be applied in drug discovery.
基金supported by the National Natural Science Foundation of China(Grant No.11872121)。
文摘The double casing warhead with sandwiched charge is a novel fragmentation warhead that can produce two groups of fragments with different velocity,and the previous work has presented a calculation formula to determine the maximum fragment velocity.The current work builds on the published formula to further develop a formula for calculating the axial distribution characteristics of the fragment velocity.For this type of warhead,the simulation of the dispersion characteristics of the detonation products at different positions shows that the detonation products at the ends have a much larger axial velocity than those in the middle,and the detonation products have a greater axial dispersion velocity when they are closer to the central axis.The loading process and the fragment velocity vary with the axial position for both casing layers,and the total velocity of the fragments is the vector sum of the radial velocity and the axial velocity.At the same axial position,the acceleration time of the inner casing is greater than that of the outer casing.For the same casing,the fragments generated at the ends have a longer acceleration time than the fragments from the middle.The proposed formula is validated with the X-ray radiography results of the four warheads previously tested experimentally and the 3D smoothedparticle hydrodynamics numerical simulation results of several series of new warheads with different configurations.The formula can accurately and reliably calculate the fragment velocity when the lengthto-diameter ratio of the charge is greater than 1.5 and the thickness of the casing is less than 20%its inner radius.This work thus provides a key reference for the theoretical analysis and the design of warheads with multiple casings.
