This article aims to explore effective ways to enhance the affinity of ideological and political course teachers in universities.By analyzing the connotation of affinity,the factors that affect the affinity of ideolog...This article aims to explore effective ways to enhance the affinity of ideological and political course teachers in universities.By analyzing the connotation of affinity,the factors that affect the affinity of ideological and political course teachers are analyzed,and corresponding improvement strategies are proposed.Research suggests that strengthening the construction of teacher ethics and conduct,improving teaching skills,enhancing emotional engagement,and enhancing practical training are key paths to enhance the affinity of ideological and political course teachers.The implementation of these paths will help improve the teaching quality and effectiveness of ideological and political courses,and promote the comprehensive development of students.展开更多
Virtual machine(VM)consolidation is an effective way to improve resource utilization and reduce energy consumption in cloud data centers.Most existing studies have considered VM consolidation as a bin-packing problem,...Virtual machine(VM)consolidation is an effective way to improve resource utilization and reduce energy consumption in cloud data centers.Most existing studies have considered VM consolidation as a bin-packing problem,but the current schemes commonly ignore the long-term relationship between VMs and hosts.In addition,there is a lack of long-term consideration for resource optimization in the VM consolidation,which results in unnecessary VM migration and increased energy consumption.To address these limitations,a VM consolidation method based on multi-step prediction and affinity-aware technique for energy-efficient cloud data centers(MPaAF-VMC)is proposed.The proposed method uses an improved linear regression prediction algorithm to predict the next-moment resource utilization of hosts and VMs,and obtains the stage demand of resources in the future period through multi-step prediction,which is realized by iterative prediction.Then,based on the multi-step prediction,an affinity model between the VM and host is designed using the first-order correlation coefficient and Euclidean distance.During the VM consolidation,the affinity value is used to select the migration VM and placement host.The proposed method is compared with the existing consolidation algorithms on the PlanetLab and Google cluster real workload data using the CloudSim simulation platform.Experimental results show that the proposed method can achieve significant improvement in reducing energy consumption,VM migration costs,and service level agreement(SLA)violations.展开更多
Affinity propagation(AP)is a widely used exemplar-based clustering approach with superior efficiency and clustering quality.Nevertheless,a common issue with AP clustering is the presence of excessive exemplars,which l...Affinity propagation(AP)is a widely used exemplar-based clustering approach with superior efficiency and clustering quality.Nevertheless,a common issue with AP clustering is the presence of excessive exemplars,which limits its ability to perform effective aggregation.This research aims to enable AP to automatically aggregate to produce fewer and more compact clusters,without changing the similarity matrix or customizing preference parameters,as done in existing enhanced approaches.An automatic aggregation enhanced affinity propagation(AAEAP)clustering algorithm is proposed,which combines a dependable partitioning clustering approach with AP to achieve this purpose.The partitioning clustering approach generates an additional set of findings with an equivalent number of clusters whenever the clustering stabilizes and the exemplars emerge.Based on these findings,mutually exclusive exemplar detection was conducted on the current AP exemplars,and a pair of unsuitable exemplars for coexistence is recommended.The recommendation is then mapped as a novel constraint,designated mutual exclusion and aggregation.To address this limitation,a modified AP clustering model is derived and the clustering is restarted,which can result in exemplar number reduction,exemplar selection adjustment,and other data point redistribution.The clustering is ultimately completed and a smaller number of clusters are obtained by repeatedly performing automatic detection and clustering until no mutually exclusive exemplars are detected.Some standard classification data sets are adopted for experiments on AAEAP and other clustering algorithms for comparison,and many internal and external clustering evaluation indexes are used to measure the clustering performance.The findings demonstrate that the AAEAP clustering algorithm demonstrates a substantial automatic aggregation impact while maintaining good clustering quality.展开更多
Drug target relationship(DTR)prediction is a rapidly evolving area of research in com-putational drug discovery.Despite recent advances in computational solutions that have overcome the challenges of in vitro and in v...Drug target relationship(DTR)prediction is a rapidly evolving area of research in com-putational drug discovery.Despite recent advances in computational solutions that have overcome the challenges of in vitro and in vivo experiments,most computational methods still focus on binary classification.They ignore the importance of binding affinity,which correctly distinguishes between on-targets and off-targets.In this study,we propose a deep learning model based on the microstruc-ture of compounds and proteins to predict drug-target binding affinity(DTA),which utilizes topo-logical structure information of drug molecules and sequence semantic information of proteins.In this model,graph attention network(GAT)is used to capture the deep features of the compound molecular graph,and bidirectional long short-term memory(BiLSTM)network is used to extract the protein sequence features,and the pharmacological context of DTA is obtained by combining the two.The results show that the proposed model has achieved superior performance in both cor-rectly predicting the value of interaction strength and correctly discriminating the ranking of bind-ing strength compared to the state-of-the-art baselines.A case study experiment on COVID-19 con-firms that the proposed DTA model can be used as an effective pre-screening tool in drug discovery.展开更多
The formulae for parameters of a negative electron affinity semiconductor(NEAS)with large mean escape depth of secondary electrons A(NEASLD)are deduced.The methods for obtaining parameters such asλ,B,E_(pom)and the m...The formulae for parameters of a negative electron affinity semiconductor(NEAS)with large mean escape depth of secondary electrons A(NEASLD)are deduced.The methods for obtaining parameters such asλ,B,E_(pom)and the maximumδandδat 100.0 keV≥E_(po)≥1.0 keV of a NEASLD with the deduced formulae are presented(B is the probability that an internal secondary electron escapes into the vacuum upon reaching the emission surface of the emitter,δis the secondary electron yield,E_(po)is the incident energy of primary electrons and E_(pom)is the E_(po)corresponding to the maximumδ).The parameters obtained here are analyzed,and it can be concluded that several parameters of NEASLDs obtained by the methods presented here agree with those obtained by other authors.The relation between the secondary electron emission and photoemission from a NEAS with large mean escape depth of excited electrons is investigated,and it is concluded that the presented method of obtaining A is more accurate than that of obtaining the corresponding parameter for a NEAS with largeλ_(ph)(λ_(ph)being the mean escape depth of photoelectrons),and that the presented method of calculating B at E_(po)>10.0 keV is more widely applicable for obtaining the corresponding parameters for a NEAS with largeλ_(ph).展开更多
During faults in a distribution network,the output power of a distributed generation(DG)may be uncertain.Moreover,the output currents of distributed power sources are also affected by the output power,resulting in unc...During faults in a distribution network,the output power of a distributed generation(DG)may be uncertain.Moreover,the output currents of distributed power sources are also affected by the output power,resulting in uncertainties in the calculation of the short-circuit current at the time of a fault.Additionally,the impacts of such uncertainties around short-circuit currents will increase with the increase of distributed power sources.Thus,it is very important to develop a method for calculating the short-circuit current while considering the uncertainties in a distribution network.In this study,an affine arithmetic algorithm for calculating short-circuit current intervals in distribution networks with distributed power sources while considering power fluctuations is presented.The proposed algorithm includes two stages.In the first stage,normal operations are considered to establish a conservative interval affine optimization model of injection currents in distributed power sources.Constrained by the fluctuation range of distributed generation power at the moment of fault occurrence,the model can then be used to solve for the fluctuation range of injected current amplitudes in distributed power sources.The second stage is implemented after a malfunction occurs.In this stage,an affine optimization model is first established.This model is developed to characterizes the short-circuit current interval of a transmission line,and is constrained by the fluctuation range of the injected current amplitude of DG during normal operations.Finally,the range of the short-circuit current amplitudes of distribution network lines after a short-circuit fault occurs is predicted.The algorithm proposed in this article obtains an interval range containing accurate results through interval operation.Compared with traditional point value calculation methods,interval calculation methods can provide more reliable analysis and calculation results.The range of short-circuit current amplitude obtained by this algorithm is slightly larger than those obtained using the Monte Carlo algorithm and the Latin hypercube sampling algorithm.Therefore,the proposed algorithm has good suitability and does not require iterative calculations,resulting in a significant improvement in computational speed compared to the Monte Carlo algorithm and the Latin hypercube sampling algorithm.Furthermore,the proposed algorithm can provide more reliable analysis and calculation results,improving the safety and stability of power systems.展开更多
This paper explores the existence of heteroclinic cycles and corresponding chaotic dynamics in a class of 3-dimensional two-zone piecewise affine systems. Moreover, the heteroclinic cycles connect two saddle foci and ...This paper explores the existence of heteroclinic cycles and corresponding chaotic dynamics in a class of 3-dimensional two-zone piecewise affine systems. Moreover, the heteroclinic cycles connect two saddle foci and intersect the switching manifold at two points and the switching manifold is composed of two perpendicular planes.展开更多
A fossil with Gnetum affinity was found in the Jianshangou Member （Barremian Age） of the Yixian Formation （Lower Cretaceous Epoch） of the Jehol Group in western Liaoning, northeastern China. The single fossil spec...A fossil with Gnetum affinity was found in the Jianshangou Member （Barremian Age） of the Yixian Formation （Lower Cretaceous Epoch） of the Jehol Group in western Liaoning, northeastern China. The single fossil specimen is represented by both elongate-cylindrical male spike strobiles which borne within a nodal bract of cauliflorous branch. The spike strobiles have apparent nodes, invisible internodes, and numerous verticillate involucral collars. The microsporangiate units within involucral collars are not seen. The male spike strobiles with verticillate involucral collars occur exclusively in Gnetum; hence, the fossil strobiles are attributed to a new taxon, Khitania columnispicata gen. ＆ sp. nov., being closely related to Gnetum. The general isotopic dating suggests an age of Barremian, ca. 125-122 million years （Myr） ago for the Jianshangou Member. The palaeoecological and palaeoclimatic inference based on the compositions of flora and fauna, and lithological characters of the fossil locality suggests that the fossil plants grew in a subtropical mesophytic forest and under a warmer climate. The remains of male spike strobiles are the first record of gnetalean macrofossil. It documents the evolution of the distinct gnetoid morphology and indicates a wider range of distribution of Gnetaceae in the Early Cretaceous than present day.展开更多
A new series of bone affinity compounds were synthesized by linking chrysophanol with 5-fluorouracil derivatives. Their bone affinity was established by hydroxyapative （HA） affinity experiment in vitro, and their cy...A new series of bone affinity compounds were synthesized by linking chrysophanol with 5-fluorouracil derivatives. Their bone affinity was established by hydroxyapative （HA） affinity experiment in vitro, and their cytostatic effects were shown by the MTT assay.展开更多
Adiabatic and vertical ionization potentials （IPs） mad valence electron affmities （EAs） of alaninamide in gas phase have been detennined using density functional theory （BLYP, B3LYP, B3P86） methods with 6-311＋...Adiabatic and vertical ionization potentials （IPs） mad valence electron affmities （EAs） of alaninamide in gas phase have been detennined using density functional theory （BLYP, B3LYP, B3P86） methods with 6-311＋＋G（d, p） basis set, respectively. IPs and EAs of alaninamide in solutions have been calculated at the B3LYP/6-311＋＋G（d, p） level. Five possible conformers of alaninamide and their charged states have been optimized employing density functional theory B3LYP method with 6-311＋＋（d, p） basis set, respectively.展开更多
Chitosan-coated nylon membranes which possess a large number of reactive groups of-CH2OH and -NH2 were prepared by coupling chitosan onto the nylon membrane. Then polylysine as ligand was also immobilized onto the com...Chitosan-coated nylon membranes which possess a large number of reactive groups of-CH2OH and -NH2 were prepared by coupling chitosan onto the nylon membrane. Then polylysine as ligand was also immobilized onto the composite membranes by 1, 1＇-carbonyl-diimidazole activation to prepare affinity membranes for bilirubin adsorption. The results showed that these membranes exhibited high binding affinity capacities for bilirubin and the adsorption isotherm fitted the Freundlich model well.展开更多
Petrologic geochemistry and isotopic chronology of the eclogites sug ge st that most of the eclogites in northern Dabie Mountains produced from the Tria ssic Yangtze subducted continental crust (lower crust and formed...Petrologic geochemistry and isotopic chronology of the eclogites sug ge st that most of the eclogites in northern Dabie Mountains produced from the Tria ssic Yangtze subducted continental crust (lower crust and formed during the deep subduction) and the metamorphosed mafic untramafic belt with eclogite, marble and meta peridotite blocks around the Mozitan Xiaotian fault zone may represen t the meta tectonic melange produced during the active subduction of an ancient oceanic slab and subsequent collision between the Yangtze and North China conti nental plates. The cooling history of the eclogites from ～900 ℃ to 300 ℃ can b e subdivided into three stages: one isothermal stage and two rapid cooling stage s. The initial stage between (230±6) and 210 Ma was a near isothermal or tempe rature rise process corresponding to the retrograded metamorphism of granulite facies with a rapid uplift of 4 mm/a, then two fast cooling stages occurred with cooling rate of ～10 ℃/Ma during 210 Ma to (172±3) Ma and ～4 ℃/Ma durin g (172±3) Ma to 130 Ma. After the peak metamorphism of eclogite facies, their in itial isothermal stage with slower uplift rate and cooling rate and high T overprinting of granulite facies metamorphism is the major difference between t he eclogites in northern Dabie Mountains from those in southern Dabie Mountains. This may be one of the most important reasons to preserve few evidences of earl ier ultrahigh pressure metamorphism.展开更多
Abstract: The Kazakhstanian plate was near the Tarim, Sino-Korean and South China-Southeast Asian plates in the Middle-Late Cambrian and Late Ordovician, and approached the Siberian plate in the other periods of the E...Abstract: The Kazakhstanian plate was near the Tarim, Sino-Korean and South China-Southeast Asian plates in the Middle-Late Cambrian and Late Ordovician, and approached the Siberian plate in the other periods of the Early Palaeozoic. The Ili and Toksun-Yamansu terranes had been split from the Tarim plate before the Middle Devonian and then went close to Angaraland in the late Early Permian. The Beishan area on the northeastern margin of the Tarim plate came close to Angaraland first in the early Early Permian. The suturing age between the Tarim and Kazakhstanian-Siberian plates is generally the same as that between the Turkey-Central Iran-Gangdise and South China-Southeast Asian plates. The suturing event took place in the early Early Permian, while the corresponding tectogeny occurred between the Early and Late Permian.展开更多
An affinity adsorbent, benzamidine Sepharose 4B, was used to separate and purify thrombin like enzymes. The p aminobenzamidine as a specific ligand was coupled to the matrix-Sepharose 4B. The recombinant thrombin like...An affinity adsorbent, benzamidine Sepharose 4B, was used to separate and purify thrombin like enzymes. The p aminobenzamidine as a specific ligand was coupled to the matrix-Sepharose 4B. The recombinant thrombin like enzyme-defibrase was used as a model in order to evaluate the efficiency of this biospecific affinity adsorbent. The homogeneity of the enzyme preparation was comfirmed as one band on sodium dodecyl sulfate polyacrylamide gel electrophoresis.展开更多
文摘This article aims to explore effective ways to enhance the affinity of ideological and political course teachers in universities.By analyzing the connotation of affinity,the factors that affect the affinity of ideological and political course teachers are analyzed,and corresponding improvement strategies are proposed.Research suggests that strengthening the construction of teacher ethics and conduct,improving teaching skills,enhancing emotional engagement,and enhancing practical training are key paths to enhance the affinity of ideological and political course teachers.The implementation of these paths will help improve the teaching quality and effectiveness of ideological and political courses,and promote the comprehensive development of students.
基金supported by the National Natural Science Foundation of China(62172089,61972087,62172090).
文摘Virtual machine(VM)consolidation is an effective way to improve resource utilization and reduce energy consumption in cloud data centers.Most existing studies have considered VM consolidation as a bin-packing problem,but the current schemes commonly ignore the long-term relationship between VMs and hosts.In addition,there is a lack of long-term consideration for resource optimization in the VM consolidation,which results in unnecessary VM migration and increased energy consumption.To address these limitations,a VM consolidation method based on multi-step prediction and affinity-aware technique for energy-efficient cloud data centers(MPaAF-VMC)is proposed.The proposed method uses an improved linear regression prediction algorithm to predict the next-moment resource utilization of hosts and VMs,and obtains the stage demand of resources in the future period through multi-step prediction,which is realized by iterative prediction.Then,based on the multi-step prediction,an affinity model between the VM and host is designed using the first-order correlation coefficient and Euclidean distance.During the VM consolidation,the affinity value is used to select the migration VM and placement host.The proposed method is compared with the existing consolidation algorithms on the PlanetLab and Google cluster real workload data using the CloudSim simulation platform.Experimental results show that the proposed method can achieve significant improvement in reducing energy consumption,VM migration costs,and service level agreement(SLA)violations.
基金supported by Research Team Development Funds of L.Xue and Z.H.Ouyang,Electronic Countermeasure Institute,National University of Defense Technology。
文摘Affinity propagation(AP)is a widely used exemplar-based clustering approach with superior efficiency and clustering quality.Nevertheless,a common issue with AP clustering is the presence of excessive exemplars,which limits its ability to perform effective aggregation.This research aims to enable AP to automatically aggregate to produce fewer and more compact clusters,without changing the similarity matrix or customizing preference parameters,as done in existing enhanced approaches.An automatic aggregation enhanced affinity propagation(AAEAP)clustering algorithm is proposed,which combines a dependable partitioning clustering approach with AP to achieve this purpose.The partitioning clustering approach generates an additional set of findings with an equivalent number of clusters whenever the clustering stabilizes and the exemplars emerge.Based on these findings,mutually exclusive exemplar detection was conducted on the current AP exemplars,and a pair of unsuitable exemplars for coexistence is recommended.The recommendation is then mapped as a novel constraint,designated mutual exclusion and aggregation.To address this limitation,a modified AP clustering model is derived and the clustering is restarted,which can result in exemplar number reduction,exemplar selection adjustment,and other data point redistribution.The clustering is ultimately completed and a smaller number of clusters are obtained by repeatedly performing automatic detection and clustering until no mutually exclusive exemplars are detected.Some standard classification data sets are adopted for experiments on AAEAP and other clustering algorithms for comparison,and many internal and external clustering evaluation indexes are used to measure the clustering performance.The findings demonstrate that the AAEAP clustering algorithm demonstrates a substantial automatic aggregation impact while maintaining good clustering quality.
文摘Drug target relationship(DTR)prediction is a rapidly evolving area of research in com-putational drug discovery.Despite recent advances in computational solutions that have overcome the challenges of in vitro and in vivo experiments,most computational methods still focus on binary classification.They ignore the importance of binding affinity,which correctly distinguishes between on-targets and off-targets.In this study,we propose a deep learning model based on the microstruc-ture of compounds and proteins to predict drug-target binding affinity(DTA),which utilizes topo-logical structure information of drug molecules and sequence semantic information of proteins.In this model,graph attention network(GAT)is used to capture the deep features of the compound molecular graph,and bidirectional long short-term memory(BiLSTM)network is used to extract the protein sequence features,and the pharmacological context of DTA is obtained by combining the two.The results show that the proposed model has achieved superior performance in both cor-rectly predicting the value of interaction strength and correctly discriminating the ranking of bind-ing strength compared to the state-of-the-art baselines.A case study experiment on COVID-19 con-firms that the proposed DTA model can be used as an effective pre-screening tool in drug discovery.
基金Project supported by the National Natural Science Foundation of China(Grant No.11873013)。
文摘The formulae for parameters of a negative electron affinity semiconductor(NEAS)with large mean escape depth of secondary electrons A(NEASLD)are deduced.The methods for obtaining parameters such asλ,B,E_(pom)and the maximumδandδat 100.0 keV≥E_(po)≥1.0 keV of a NEASLD with the deduced formulae are presented(B is the probability that an internal secondary electron escapes into the vacuum upon reaching the emission surface of the emitter,δis the secondary electron yield,E_(po)is the incident energy of primary electrons and E_(pom)is the E_(po)corresponding to the maximumδ).The parameters obtained here are analyzed,and it can be concluded that several parameters of NEASLDs obtained by the methods presented here agree with those obtained by other authors.The relation between the secondary electron emission and photoemission from a NEAS with large mean escape depth of excited electrons is investigated,and it is concluded that the presented method of obtaining A is more accurate than that of obtaining the corresponding parameter for a NEAS with largeλ_(ph)(λ_(ph)being the mean escape depth of photoelectrons),and that the presented method of calculating B at E_(po)>10.0 keV is more widely applicable for obtaining the corresponding parameters for a NEAS with largeλ_(ph).
基金This article was supported by the general project“Research on Wind and Photovoltaic Fault Characteristics and Practical Short Circuit Calculation Model”(521820200097)of Jiangxi Electric Power Company.
文摘During faults in a distribution network,the output power of a distributed generation(DG)may be uncertain.Moreover,the output currents of distributed power sources are also affected by the output power,resulting in uncertainties in the calculation of the short-circuit current at the time of a fault.Additionally,the impacts of such uncertainties around short-circuit currents will increase with the increase of distributed power sources.Thus,it is very important to develop a method for calculating the short-circuit current while considering the uncertainties in a distribution network.In this study,an affine arithmetic algorithm for calculating short-circuit current intervals in distribution networks with distributed power sources while considering power fluctuations is presented.The proposed algorithm includes two stages.In the first stage,normal operations are considered to establish a conservative interval affine optimization model of injection currents in distributed power sources.Constrained by the fluctuation range of distributed generation power at the moment of fault occurrence,the model can then be used to solve for the fluctuation range of injected current amplitudes in distributed power sources.The second stage is implemented after a malfunction occurs.In this stage,an affine optimization model is first established.This model is developed to characterizes the short-circuit current interval of a transmission line,and is constrained by the fluctuation range of the injected current amplitude of DG during normal operations.Finally,the range of the short-circuit current amplitudes of distribution network lines after a short-circuit fault occurs is predicted.The algorithm proposed in this article obtains an interval range containing accurate results through interval operation.Compared with traditional point value calculation methods,interval calculation methods can provide more reliable analysis and calculation results.The range of short-circuit current amplitude obtained by this algorithm is slightly larger than those obtained using the Monte Carlo algorithm and the Latin hypercube sampling algorithm.Therefore,the proposed algorithm has good suitability and does not require iterative calculations,resulting in a significant improvement in computational speed compared to the Monte Carlo algorithm and the Latin hypercube sampling algorithm.Furthermore,the proposed algorithm can provide more reliable analysis and calculation results,improving the safety and stability of power systems.
文摘This paper explores the existence of heteroclinic cycles and corresponding chaotic dynamics in a class of 3-dimensional two-zone piecewise affine systems. Moreover, the heteroclinic cycles connect two saddle foci and intersect the switching manifold at two points and the switching manifold is composed of two perpendicular planes.
基金supported by the pilot project of Knowledge Innovation Program of the Chinese Academy of Sciences (KZCX2-114)National Natural Science Foundation of China (40632010)
文摘A fossil with Gnetum affinity was found in the Jianshangou Member （Barremian Age） of the Yixian Formation （Lower Cretaceous Epoch） of the Jehol Group in western Liaoning, northeastern China. The single fossil specimen is represented by both elongate-cylindrical male spike strobiles which borne within a nodal bract of cauliflorous branch. The spike strobiles have apparent nodes, invisible internodes, and numerous verticillate involucral collars. The microsporangiate units within involucral collars are not seen. The male spike strobiles with verticillate involucral collars occur exclusively in Gnetum; hence, the fossil strobiles are attributed to a new taxon, Khitania columnispicata gen. ＆ sp. nov., being closely related to Gnetum. The general isotopic dating suggests an age of Barremian, ca. 125-122 million years （Myr） ago for the Jianshangou Member. The palaeoecological and palaeoclimatic inference based on the compositions of flora and fauna, and lithological characters of the fossil locality suggests that the fossil plants grew in a subtropical mesophytic forest and under a warmer climate. The remains of male spike strobiles are the first record of gnetalean macrofossil. It documents the evolution of the distinct gnetoid morphology and indicates a wider range of distribution of Gnetaceae in the Early Cretaceous than present day.
基金the National Natural Science Foundation of China （No.30371682）.
文摘A new series of bone affinity compounds were synthesized by linking chrysophanol with 5-fluorouracil derivatives. Their bone affinity was established by hydroxyapative （HA） affinity experiment in vitro, and their cytostatic effects were shown by the MTT assay.
基金the Natural Science Foundation of Shandong Province (Z2004F01)the State Key Laboratory Foundation of Crystal Materialthe National Natural Science Foundation of China (29673025)
文摘Adiabatic and vertical ionization potentials （IPs） mad valence electron affmities （EAs） of alaninamide in gas phase have been detennined using density functional theory （BLYP, B3LYP, B3P86） methods with 6-311＋＋G（d, p） basis set, respectively. IPs and EAs of alaninamide in solutions have been calculated at the B3LYP/6-311＋＋G（d, p） level. Five possible conformers of alaninamide and their charged states have been optimized employing density functional theory B3LYP method with 6-311＋＋（d, p） basis set, respectively.
基金We are extremely grateful to the National Natural Science Foundation of China for supporting this research(No.29776036).
文摘Chitosan-coated nylon membranes which possess a large number of reactive groups of-CH2OH and -NH2 were prepared by coupling chitosan onto the nylon membrane. Then polylysine as ligand was also immobilized onto the composite membranes by 1, 1＇-carbonyl-diimidazole activation to prepare affinity membranes for bilirubin adsorption. The results showed that these membranes exhibited high binding affinity capacities for bilirubin and the adsorption isotherm fitted the Freundlich model well.
文摘Petrologic geochemistry and isotopic chronology of the eclogites sug ge st that most of the eclogites in northern Dabie Mountains produced from the Tria ssic Yangtze subducted continental crust (lower crust and formed during the deep subduction) and the metamorphosed mafic untramafic belt with eclogite, marble and meta peridotite blocks around the Mozitan Xiaotian fault zone may represen t the meta tectonic melange produced during the active subduction of an ancient oceanic slab and subsequent collision between the Yangtze and North China conti nental plates. The cooling history of the eclogites from ～900 ℃ to 300 ℃ can b e subdivided into three stages: one isothermal stage and two rapid cooling stage s. The initial stage between (230±6) and 210 Ma was a near isothermal or tempe rature rise process corresponding to the retrograded metamorphism of granulite facies with a rapid uplift of 4 mm/a, then two fast cooling stages occurred with cooling rate of ～10 ℃/Ma during 210 Ma to (172±3) Ma and ～4 ℃/Ma durin g (172±3) Ma to 130 Ma. After the peak metamorphism of eclogite facies, their in itial isothermal stage with slower uplift rate and cooling rate and high T overprinting of granulite facies metamorphism is the major difference between t he eclogites in northern Dabie Mountains from those in southern Dabie Mountains. This may be one of the most important reasons to preserve few evidences of earl ier ultrahigh pressure metamorphism.
文摘Abstract: The Kazakhstanian plate was near the Tarim, Sino-Korean and South China-Southeast Asian plates in the Middle-Late Cambrian and Late Ordovician, and approached the Siberian plate in the other periods of the Early Palaeozoic. The Ili and Toksun-Yamansu terranes had been split from the Tarim plate before the Middle Devonian and then went close to Angaraland in the late Early Permian. The Beishan area on the northeastern margin of the Tarim plate came close to Angaraland first in the early Early Permian. The suturing age between the Tarim and Kazakhstanian-Siberian plates is generally the same as that between the Turkey-Central Iran-Gangdise and South China-Southeast Asian plates. The suturing event took place in the early Early Permian, while the corresponding tectogeny occurred between the Early and Late Permian.
文摘An affinity adsorbent, benzamidine Sepharose 4B, was used to separate and purify thrombin like enzymes. The p aminobenzamidine as a specific ligand was coupled to the matrix-Sepharose 4B. The recombinant thrombin like enzyme-defibrase was used as a model in order to evaluate the efficiency of this biospecific affinity adsorbent. The homogeneity of the enzyme preparation was comfirmed as one band on sodium dodecyl sulfate polyacrylamide gel electrophoresis.
