A comprehensive mathematical model of annulus-electromagnetic direct chill (A-EMDC) casting of A357 aluminum alloy was established with corresponding experimental verification. The model was based on a combination o...A comprehensive mathematical model of annulus-electromagnetic direct chill (A-EMDC) casting of A357 aluminum alloy was established with corresponding experimental verification. The model was based on a combination of the commercial finite element package ANSYS and the commercial finite volume package FLUENT. The effects of structural parameters on fluid flow, temperature field and solidification during A-EMDC process were investigated numerically. The results show that structural parameters such as annulus gap width, annulus gap position, and centre pipe length influence the flow and temperature fields. The smaller the annulus gap width is, the more uniform the temperature is, and the smaller the temperature gradient is. With increasing the centre pipe length, the circular flow would decrease due to the dislocation of centre pipe. Specially, when the annulus gap is located at periphery of the billet, the temperature gradient of the longitudinal direction in the solidification region falls evidently.展开更多
Four different methods,namely mineralogical analysis,three-stage BCR sequential extraction procedure,dynamic leaching test and Hakanson Potential Ecological Risk Index Method were used to access the environmental acti...Four different methods,namely mineralogical analysis,three-stage BCR sequential extraction procedure,dynamic leaching test and Hakanson Potential Ecological Risk Index Method were used to access the environmental activity and potential ecological risks of heavy metals in zinc leaching residue.The results demonstrate that the environmental activity of heavy metals declines in the following order:CdZnCuAsPb.Potential ecological risk indices for single heavy metal are CdZnCuAsPb.Cd has serious potential ecological risk to the ecological environment and contributes most to the potential toxicity response indices for various heavy metals in the residue.展开更多
This paper introduces a novel digital transceiver for the cordless telephone zero (CT0) standard,which uses a digital modulation and demodulation technique to handle the signal instead of the traditional analog meth...This paper introduces a novel digital transceiver for the cordless telephone zero (CT0) standard,which uses a digital modulation and demodulation technique to handle the signal instead of the traditional analog meth-od. In the transmitter,a fractional-N phase locked loop (PLL) is utilized to realize the continuous phase frequency shift key (CPFSK) modulation,and a 2 Ts raised cosine (2RC) shaping technique is used to reduce the occupied bandwidth. In the receiver,a novel digital method is proposed to demodulate the 2RC CPFSK signal. This chip is fabricated using an SMIC 0.35μm mixed signal CMOS process with a die size of 2mm × 2mm. With an external low noise amplifier (LNA),the sensitivity of the chip is better than -103dBm.展开更多
To investigate pharmacokinetics ofbaicalin after an oral administration of different Shuang-Huang-Lian (SHL) formulations to rats. Different SIlL formulations were orally administered to rats. The concentrations of ...To investigate pharmacokinetics ofbaicalin after an oral administration of different Shuang-Huang-Lian (SHL) formulations to rats. Different SIlL formulations were orally administered to rats. The concentrations of baicalin in rat plasma were determined by HPLC, the non-compartmental pharmacokinetic parameters and population pharmacokinetic parameters of baicalin were estimated by WinNonlin and NONMEM. The plasma concentration profiles of baicalin demonstrated double-peak phenomenon except for group microemulsion prescription 2. Population pharmacokinetic model developed includes four covariates, which were the effect of formulation (FORM) on CL/F and V/F, the effect of body weight (BW) on Ka, and the effect of gender (GEND) on V/F. Numbers 1 to 6 denote SHL formulation decoction, oral liquid, colloidal solution, microemulsion prescription 1, microemulsion prescription 2 and granule, respectively. The equations for the parameters are as following: CL/F = (0.432 + 0.529). e^ηCl L/h if formulation was 2 or 6, otherwise CL/F = 0.432. e^ηCl L/h ; V/F = (11.3- 4.03 - 3.87. GEND). e^ηv L if formulation was 5, otherwise V/F = (11.3 - 3.87. GEND). e^ηv L ; Ka = 0.475. [1 - 0.0223. (BW - 195.1)]. e^ηKah^-1. SHL formulations have significant effects on the nharmacokinefic narameters.展开更多
AIM: To investigate clinical significance of Pin1 and β-catenin expression in colorectal cancers and to demonstrate the relationship of their expression. METHODS: The role of Pin1 and β-catenin protein in colorect...AIM: To investigate clinical significance of Pin1 and β-catenin expression in colorectal cancers and to demonstrate the relationship of their expression. METHODS: The role of Pin1 and β-catenin protein in colorectal tumorigenesis and their clinicopathologic significance were analyzed by immunohistochemistry, and correlation between Pin1 and β-catenin protein expressions was also studied in 124 patients with colorectal cancer who were surgically treated. RESULTS: Normal colonic epithelium either failed to express or showed focal and weak expression of Pin1 and β-catenin. Overexpression of Pin1 and β-catenin protein was found in 23 (18.54%) and 50 (40.3%) of 124 colorectal cancers, respectively. Overexpression of both proteins was not related to the lymph node metastasis, tumor stage and survival period after excision. Survival analysis results indicated that tumor stage was a valuable predictor of survival. Interestingly, a significant correlation was found between Pin1 and β-catenin protein expression. CONCLUSION: Overexpression of Pin1 and β-catenin may be closely related with the development and/or progression of colorectal carcinoma and further supports that Pin1 overexpression might contribute to the upregulation of β-catenin.展开更多
Microstructure instabilities of the fully lamellar Ti-45Al-8.5Nb-(W,B,Y) alloy were investigated by SEM and TEM after long-term thermal cycling(500 and 1000 thermal cycles) at 900 °C. Two major categories of ...Microstructure instabilities of the fully lamellar Ti-45Al-8.5Nb-(W,B,Y) alloy were investigated by SEM and TEM after long-term thermal cycling(500 and 1000 thermal cycles) at 900 °C. Two major categories of microstructure instability were produced in the alloy after the thermal cycling: 1) The discontinuous coarsening implies that grain boundary migrations are inclined to occur in the Al-segregation region after the long-term thermal cycling, especially after 1000 thermal cycles. Al-segregation can be reduced during the process of long-term thermal cycling as a result of element diffusion; 2) The α2 lamellae become thinner and are broken after 1000 thermal cycles caused by the dissolution of α2 lamellae through phase transformation of α2→γ. The γ grains nucleate within the α2 lamellae or(α2+γ) lamellae in a random direction.展开更多
Three types of natural connection between atoll islets are described. Causeway, as an artificial way of connecting islets, makes a connection to be completed in a few months. In this case shore adjustment becomes more...Three types of natural connection between atoll islets are described. Causeway, as an artificial way of connecting islets, makes a connection to be completed in a few months. In this case shore adjustment becomes more vigorous than that in natural conditions, resulting in lagoon shore erosion. A causeway without short bridges or culverts should be built close to the lagoon shore to reduce lagoon shore erosion. A causeway-crossing channel assemblage is the worst type among all of the connection engineering constructions because the crossing channel traps sediment and further transports it out of the channel, resulting in long period coastal erosion. Reforming Nippon Causeway in Tarawa Atoll, Kiribati by simple means will stop sand loss, reduce shore erosion and greatly upgrade its stability.展开更多
Engineering construction has major influence on the permafrost environment.This paper analyzes the interaction between engineering construction and permafrost environment along the Chaidaer-Muli Railway(simply,CMR) ba...Engineering construction has major influence on the permafrost environment.This paper analyzes the interaction between engineering construction and permafrost environment along the Chaidaer-Muli Railway(simply,CMR) based on the press-state-response(PSR) framework.The permafrost environmental system is divided into three subsystems,consisting of permafrost thermal stability,proneness to the freeze-thawing erosion and permafrost ecological fragility.Each subsystem considers its most important influencing factors.Catastrophe Progression Method(CPM) is applied to calculate the current environment condition along the railway.The result indicates that:(1) as far as the thermal stability is concerned,most sections along the CMR are mainly concentrated in rank Ⅲ(fair situation),and a few in Ⅱ(good situation) and Ⅳ(bad situation),respectively;(2) for the proneness tothe freeze-thawing erosion,the entire railway route falls largely in rank Ⅱ(good situation);(3) along the CMR,the ecological fragility of the permafrost environment is in rank Ⅱ(good situation),or slightly fragile;(4) overall,the permafrost environments along the CMR are in rank Ⅲ(fair situation) or Ⅱcondition(good situation).In general,the permafrost environment along the CMR is fair.It is mainly because a series of active measures of protecting permafrost were taken for stabilizing the CMR foundation soils.On the one hand,we should try our best to minimize the influences that engineering activities have exerted on ecology and environment,on the other hand,the positive measures have made improvements to prevent the permafrost environment from deterioration.展开更多
Two popular traditional join algorithms and their parallel versions are introduced. When designing join algorithms in serial computing environment, decomposing inner relation is considered as the right direction to sa...Two popular traditional join algorithms and their parallel versions are introduced. When designing join algorithms in serial computing environment, decomposing inner relation is considered as the right direction to save disk I/Os. However, two different decomposition algorithms are compared, such as inner vs. outer decomposition first algorithms for tuple-based and block-based nested loop joins, showing that the proposed approach is 20% better than general approach. Also lemmas are proved, when we have to use the outer decomposition first parallel join algorithms.展开更多
The present paper is talking about the recent situation of the archeological buildings which exist through modern urban environments. Urban expansion has a large effect on the archeological buildings continuity since ...The present paper is talking about the recent situation of the archeological buildings which exist through modern urban environments. Urban expansion has a large effect on the archeological buildings continuity since such type of development impresses several serious challenges which conservation plans as well as preservation polices must deal with. A number of that main challenges are mega-constructions (tunnels, damps, roads, etc.), pollution, socio-cultural impacts and traffic. Within Um Qias, the archeological buildings face similar challenges consistent with the urban environment where it is presented and that challenges are reviewed in the local community behavior.展开更多
Influences of gap size and cyclic-thermal-shock treatment on the mechanical properties of transient liquid phase(TLP) bonded IN-738 LC superalloy were investigated. For this purpose, TLP bonding of IN-738 LC superal...Influences of gap size and cyclic-thermal-shock treatment on the mechanical properties of transient liquid phase(TLP) bonded IN-738 LC superalloy were investigated. For this purpose, TLP bonding of IN-738 LC superalloy was carried out in a vacuum furnace using powdered AMS 4777 as the filler metal. The results showed that isothermal solidified zone(ISZ) consisted of Ni solid-solution and the distribution of alloying elements was homogeneous. High hardness of HV 409 and high shear strength of 506 MPa were observed in 40 μm gap sample. Alloying elements formed γ′ precipitates and the solid-solution in the ISZ. Hardness and shear strength of bonds were reduced with increasing the gap size(in range of 40-120 μm). The fractured surfaces of complete isothermal solidified bonds showed dimpled rupture, but athermal solidified bonds showed cleavage fracture surface. 10, 20, 30 and 40 thermal-shock cycles were applied to 80 μm gap samples, respectively. The shear strength of the bond was measured to be 268 MPa after the 40 th thermal-shock cycle. The sample with gap size of 80 μm was failed due to crack nucleation on faying surface at 45 th thermal-shock cycle. The amount of the produced brittleness due to quenching the samples in water bath was attributed to the number of thermal-shock cycles.展开更多
The joint grid system, which consists of the developed collar grid, the virtual grid and other grids, was used in the embedding technique to solve the problem of finding interpolating cells of the internal and externa...The joint grid system, which consists of the developed collar grid, the virtual grid and other grids, was used in the embedding technique to solve the problem of finding interpolating cells of the internal and external boundary points near the joint regions. With different boundary plane generated along different fixed surface, the collar grid obtained using hyperbolic partial equations can ensure to generate high quality grids and to provide real interpolating cells for the boundary points in the blanking regions. The virtual grid was used to convert solid wall boundary conditions into an interface condition, however, no fluid flow computations were conducted within the virtual grid. The computational result of body strake wing shows that the current developed embedding technique with joint grid system can effectively treat the geometry and can more accurately predict the flow over complexconfiguration with intersecting surfaces.展开更多
Using the theories of population carrying capacity and ecological elasticity in other fields for reference, the connotation of regional human settlement system was defined from the viewpoint of the complex relationshi...Using the theories of population carrying capacity and ecological elasticity in other fields for reference, the connotation of regional human settlement system was defined from the viewpoint of the complex relationship among the factors such as regional population, resources, environment and economic and social development in the context of China′s rapid urbanization. Then the concept and characterization methods of the regional human settlement carrying capacity were proposed by means of population scale. Furthermore, a model of carrying capacity-pressure-state-response(CPSR) on regional human settlement system was established by referencing pressure-state-response(PSR) model, and the Catastrophe Theory was introduced to determine the corresponding standards of multi-criteria programming and evaluation. Taking Dalian City, Liaoning Province, China as an example, an empirical analysis on evaluation of human settlement system from 2000 to 2012 was carried out. The results showed that the carrying capacity of human settlement system in Dalian was fluctuating between 9.6 × 106 to 10 × 106 persons with a quantitative stage of the dynamic regulation. During the research period the load index of human settlement system in Dalian dropped from 0.96 to 0.84 with a lower pressure of human settlement system than the national average level. And the emergency response grades of human settlement system in Dalian were kept in grade Ⅱ(orange warning) or grade Ⅲ(yellow warning). Human settlement system of Dalian was in slight security state as a whole, but the load had a tendency of increase in recent years. The related departments should pay close attention to regional human settlement system and take active measures to improve human settlement by both intensity control and total quantity control. By comparison, analysis and discussion, it was considered that the results were basically accordded with the current situations of human settlement in Dalian, and the evaluation results were more reliable, visualized and easily applied in practice. Therefore, the above-mentioned concepts, characterization and evaluation methods of the regional human settlement system and carrying capacity could provide a new thought and method for quantitative evaluation of human settlement.展开更多
The continuous affinity- recycle extraction (CARE) process is extended ic a system with ultrafiltration membranes. The mathematical model of the process is established by taking into account membrane rejections to th...The continuous affinity- recycle extraction (CARE) process is extended ic a system with ultrafiltration membranes. The mathematical model of the process is established by taking into account membrane rejections to the components in a crude mixture. The process performance, defined as concentration factor (CF ), purification factor (PF ) and recovery yield (REC), is analyzed by computer simulations. The results show that CF and REC increase, but PF decreases with the membrane rejection. It is likely that optimum operating conditions exist to give the best process performance because the increases in eluant and affinity-recycle flow rate improve REC but decrease PF.展开更多
基金Project (2009AA03Z534) supported by the Hi-tech Research and Development Program of China Project (2006CB605203) supported by National Basic Research Program of China
文摘A comprehensive mathematical model of annulus-electromagnetic direct chill (A-EMDC) casting of A357 aluminum alloy was established with corresponding experimental verification. The model was based on a combination of the commercial finite element package ANSYS and the commercial finite volume package FLUENT. The effects of structural parameters on fluid flow, temperature field and solidification during A-EMDC process were investigated numerically. The results show that structural parameters such as annulus gap width, annulus gap position, and centre pipe length influence the flow and temperature fields. The smaller the annulus gap width is, the more uniform the temperature is, and the smaller the temperature gradient is. With increasing the centre pipe length, the circular flow would decrease due to the dislocation of centre pipe. Specially, when the annulus gap is located at periphery of the billet, the temperature gradient of the longitudinal direction in the solidification region falls evidently.
基金Project(50925417) supported by the National Natural Science Funds for Distinguished Young Scholar of ChinaProject(2010AA065203) supported by the High Technology Research and Development Program of China+2 种基金Project(2010-609) Supported by the Scientific Research Foundation for the Returned Overseas Chinese Scholars,Ministry of Education,ChinaProject(ncet-10-0840) supported by Program for New Century Excellent Talents in UniversityProject(2012FJ1080) supported by Key Projects of Science and Technology of Hunan Province,China
文摘Four different methods,namely mineralogical analysis,three-stage BCR sequential extraction procedure,dynamic leaching test and Hakanson Potential Ecological Risk Index Method were used to access the environmental activity and potential ecological risks of heavy metals in zinc leaching residue.The results demonstrate that the environmental activity of heavy metals declines in the following order:CdZnCuAsPb.Potential ecological risk indices for single heavy metal are CdZnCuAsPb.Cd has serious potential ecological risk to the ecological environment and contributes most to the potential toxicity response indices for various heavy metals in the residue.
文摘This paper introduces a novel digital transceiver for the cordless telephone zero (CT0) standard,which uses a digital modulation and demodulation technique to handle the signal instead of the traditional analog meth-od. In the transmitter,a fractional-N phase locked loop (PLL) is utilized to realize the continuous phase frequency shift key (CPFSK) modulation,and a 2 Ts raised cosine (2RC) shaping technique is used to reduce the occupied bandwidth. In the receiver,a novel digital method is proposed to demodulate the 2RC CPFSK signal. This chip is fabricated using an SMIC 0.35μm mixed signal CMOS process with a die size of 2mm × 2mm. With an external low noise amplifier (LNA),the sensitivity of the chip is better than -103dBm.
基金National Natural Science Foundation of China (Grant No. 30472195)
文摘To investigate pharmacokinetics ofbaicalin after an oral administration of different Shuang-Huang-Lian (SHL) formulations to rats. Different SIlL formulations were orally administered to rats. The concentrations of baicalin in rat plasma were determined by HPLC, the non-compartmental pharmacokinetic parameters and population pharmacokinetic parameters of baicalin were estimated by WinNonlin and NONMEM. The plasma concentration profiles of baicalin demonstrated double-peak phenomenon except for group microemulsion prescription 2. Population pharmacokinetic model developed includes four covariates, which were the effect of formulation (FORM) on CL/F and V/F, the effect of body weight (BW) on Ka, and the effect of gender (GEND) on V/F. Numbers 1 to 6 denote SHL formulation decoction, oral liquid, colloidal solution, microemulsion prescription 1, microemulsion prescription 2 and granule, respectively. The equations for the parameters are as following: CL/F = (0.432 + 0.529). e^ηCl L/h if formulation was 2 or 6, otherwise CL/F = 0.432. e^ηCl L/h ; V/F = (11.3- 4.03 - 3.87. GEND). e^ηv L if formulation was 5, otherwise V/F = (11.3 - 3.87. GEND). e^ηv L ; Ka = 0.475. [1 - 0.0223. (BW - 195.1)]. e^ηKah^-1. SHL formulations have significant effects on the nharmacokinefic narameters.
基金Supported by the Korea Science and Engineering Foundation (KOSEF) through the Cell Death Disease Research Center at The Catholic University of Korea, No. R13-2002-005-01004-0
文摘AIM: To investigate clinical significance of Pin1 and β-catenin expression in colorectal cancers and to demonstrate the relationship of their expression. METHODS: The role of Pin1 and β-catenin protein in colorectal tumorigenesis and their clinicopathologic significance were analyzed by immunohistochemistry, and correlation between Pin1 and β-catenin protein expressions was also studied in 124 patients with colorectal cancer who were surgically treated. RESULTS: Normal colonic epithelium either failed to express or showed focal and weak expression of Pin1 and β-catenin. Overexpression of Pin1 and β-catenin protein was found in 23 (18.54%) and 50 (40.3%) of 124 colorectal cancers, respectively. Overexpression of both proteins was not related to the lymph node metastasis, tumor stage and survival period after excision. Survival analysis results indicated that tumor stage was a valuable predictor of survival. Interestingly, a significant correlation was found between Pin1 and β-catenin protein expression. CONCLUSION: Overexpression of Pin1 and β-catenin may be closely related with the development and/or progression of colorectal carcinoma and further supports that Pin1 overexpression might contribute to the upregulation of β-catenin.
基金Project(2011CB605500)supported by National Basic Research Program of ChinaProject(51171015)supported by National Natural Science Foundation of China+2 种基金Project(2012M520166)supported by China Postdoctoral Science FoundationProject(2012Z-06)supported by State Key Laboratory for Advanced Metals and Materials,University of Science and Technology Beijing,ChinaProject(FRF-TP-12-164A)supported by Fundamental Research Funds for the Central Universities of China
文摘Microstructure instabilities of the fully lamellar Ti-45Al-8.5Nb-(W,B,Y) alloy were investigated by SEM and TEM after long-term thermal cycling(500 and 1000 thermal cycles) at 900 °C. Two major categories of microstructure instability were produced in the alloy after the thermal cycling: 1) The discontinuous coarsening implies that grain boundary migrations are inclined to occur in the Al-segregation region after the long-term thermal cycling, especially after 1000 thermal cycles. Al-segregation can be reduced during the process of long-term thermal cycling as a result of element diffusion; 2) The α2 lamellae become thinner and are broken after 1000 thermal cycles caused by the dissolution of α2 lamellae through phase transformation of α2→γ. The γ grains nucleate within the α2 lamellae or(α2+γ) lamellae in a random direction.
基金funded by the Ministry of Foreign Economic Co-operation and Trade,China.
文摘Three types of natural connection between atoll islets are described. Causeway, as an artificial way of connecting islets, makes a connection to be completed in a few months. In this case shore adjustment becomes more vigorous than that in natural conditions, resulting in lagoon shore erosion. A causeway without short bridges or culverts should be built close to the lagoon shore to reduce lagoon shore erosion. A causeway-crossing channel assemblage is the worst type among all of the connection engineering constructions because the crossing channel traps sediment and further transports it out of the channel, resulting in long period coastal erosion. Reforming Nippon Causeway in Tarawa Atoll, Kiribati by simple means will stop sand loss, reduce shore erosion and greatly upgrade its stability.
基金supported by the Major State Basic Research Development Program of China (No.2013CBA01803)the National Natural Science Foundation of China (No.41271084 and 41501079)+1 种基金the Project Funded by China Postdoctoral Science Foundation (No.2015M582724 and 2016T90962)the Chinese Academy of Sciences (CAS) Key Research Program (No.KZZD-EW-13)
文摘Engineering construction has major influence on the permafrost environment.This paper analyzes the interaction between engineering construction and permafrost environment along the Chaidaer-Muli Railway(simply,CMR) based on the press-state-response(PSR) framework.The permafrost environmental system is divided into three subsystems,consisting of permafrost thermal stability,proneness to the freeze-thawing erosion and permafrost ecological fragility.Each subsystem considers its most important influencing factors.Catastrophe Progression Method(CPM) is applied to calculate the current environment condition along the railway.The result indicates that:(1) as far as the thermal stability is concerned,most sections along the CMR are mainly concentrated in rank Ⅲ(fair situation),and a few in Ⅱ(good situation) and Ⅳ(bad situation),respectively;(2) for the proneness tothe freeze-thawing erosion,the entire railway route falls largely in rank Ⅱ(good situation);(3) along the CMR,the ecological fragility of the permafrost environment is in rank Ⅱ(good situation),or slightly fragile;(4) overall,the permafrost environments along the CMR are in rank Ⅲ(fair situation) or Ⅱcondition(good situation).In general,the permafrost environment along the CMR is fair.It is mainly because a series of active measures of protecting permafrost were taken for stabilizing the CMR foundation soils.On the one hand,we should try our best to minimize the influences that engineering activities have exerted on ecology and environment,on the other hand,the positive measures have made improvements to prevent the permafrost environment from deterioration.
基金supported by the National Research Foundation (NRF) of Korea through contract N-14-NMIR06
文摘Two popular traditional join algorithms and their parallel versions are introduced. When designing join algorithms in serial computing environment, decomposing inner relation is considered as the right direction to save disk I/Os. However, two different decomposition algorithms are compared, such as inner vs. outer decomposition first algorithms for tuple-based and block-based nested loop joins, showing that the proposed approach is 20% better than general approach. Also lemmas are proved, when we have to use the outer decomposition first parallel join algorithms.
文摘The present paper is talking about the recent situation of the archeological buildings which exist through modern urban environments. Urban expansion has a large effect on the archeological buildings continuity since such type of development impresses several serious challenges which conservation plans as well as preservation polices must deal with. A number of that main challenges are mega-constructions (tunnels, damps, roads, etc.), pollution, socio-cultural impacts and traffic. Within Um Qias, the archeological buildings face similar challenges consistent with the urban environment where it is presented and that challenges are reviewed in the local community behavior.
文摘Influences of gap size and cyclic-thermal-shock treatment on the mechanical properties of transient liquid phase(TLP) bonded IN-738 LC superalloy were investigated. For this purpose, TLP bonding of IN-738 LC superalloy was carried out in a vacuum furnace using powdered AMS 4777 as the filler metal. The results showed that isothermal solidified zone(ISZ) consisted of Ni solid-solution and the distribution of alloying elements was homogeneous. High hardness of HV 409 and high shear strength of 506 MPa were observed in 40 μm gap sample. Alloying elements formed γ′ precipitates and the solid-solution in the ISZ. Hardness and shear strength of bonds were reduced with increasing the gap size(in range of 40-120 μm). The fractured surfaces of complete isothermal solidified bonds showed dimpled rupture, but athermal solidified bonds showed cleavage fracture surface. 10, 20, 30 and 40 thermal-shock cycles were applied to 80 μm gap samples, respectively. The shear strength of the bond was measured to be 268 MPa after the 40 th thermal-shock cycle. The sample with gap size of 80 μm was failed due to crack nucleation on faying surface at 45 th thermal-shock cycle. The amount of the produced brittleness due to quenching the samples in water bath was attributed to the number of thermal-shock cycles.
文摘The joint grid system, which consists of the developed collar grid, the virtual grid and other grids, was used in the embedding technique to solve the problem of finding interpolating cells of the internal and external boundary points near the joint regions. With different boundary plane generated along different fixed surface, the collar grid obtained using hyperbolic partial equations can ensure to generate high quality grids and to provide real interpolating cells for the boundary points in the blanking regions. The virtual grid was used to convert solid wall boundary conditions into an interface condition, however, no fluid flow computations were conducted within the virtual grid. The computational result of body strake wing shows that the current developed embedding technique with joint grid system can effectively treat the geometry and can more accurately predict the flow over complexconfiguration with intersecting surfaces.
基金Under the auspices of Project of Humanities and Social Sciences,Ministry of Education of China(No.14YJAZH112)Social Sciences Planning Project of Liaoning Province(No.L13BJL019)+1 种基金Economic and Social Development Project of Liaoning Province(No.2014lslktzixxjx-06)Specialized Research Fund for Doctoral Program of Higher Education,Ministry of Education of China(No.20122136110003)
文摘Using the theories of population carrying capacity and ecological elasticity in other fields for reference, the connotation of regional human settlement system was defined from the viewpoint of the complex relationship among the factors such as regional population, resources, environment and economic and social development in the context of China′s rapid urbanization. Then the concept and characterization methods of the regional human settlement carrying capacity were proposed by means of population scale. Furthermore, a model of carrying capacity-pressure-state-response(CPSR) on regional human settlement system was established by referencing pressure-state-response(PSR) model, and the Catastrophe Theory was introduced to determine the corresponding standards of multi-criteria programming and evaluation. Taking Dalian City, Liaoning Province, China as an example, an empirical analysis on evaluation of human settlement system from 2000 to 2012 was carried out. The results showed that the carrying capacity of human settlement system in Dalian was fluctuating between 9.6 × 106 to 10 × 106 persons with a quantitative stage of the dynamic regulation. During the research period the load index of human settlement system in Dalian dropped from 0.96 to 0.84 with a lower pressure of human settlement system than the national average level. And the emergency response grades of human settlement system in Dalian were kept in grade Ⅱ(orange warning) or grade Ⅲ(yellow warning). Human settlement system of Dalian was in slight security state as a whole, but the load had a tendency of increase in recent years. The related departments should pay close attention to regional human settlement system and take active measures to improve human settlement by both intensity control and total quantity control. By comparison, analysis and discussion, it was considered that the results were basically accordded with the current situations of human settlement in Dalian, and the evaluation results were more reliable, visualized and easily applied in practice. Therefore, the above-mentioned concepts, characterization and evaluation methods of the regional human settlement system and carrying capacity could provide a new thought and method for quantitative evaluation of human settlement.
文摘The continuous affinity- recycle extraction (CARE) process is extended ic a system with ultrafiltration membranes. The mathematical model of the process is established by taking into account membrane rejections to the components in a crude mixture. The process performance, defined as concentration factor (CF ), purification factor (PF ) and recovery yield (REC), is analyzed by computer simulations. The results show that CF and REC increase, but PF decreases with the membrane rejection. It is likely that optimum operating conditions exist to give the best process performance because the increases in eluant and affinity-recycle flow rate improve REC but decrease PF.