3D digital design for cranes’ structures based on hybrid software architecture of Client/Server and Browser/Server is introduced in this paper. Based on Pro/ENGINEER platform,3D parametric model family is built to al...3D digital design for cranes’ structures based on hybrid software architecture of Client/Server and Browser/Server is introduced in this paper. Based on Pro/ENGINEER platform,3D parametric model family is built to allow generation of feasible configurations of cranes’ structures in Client/Server framework. Taking use of Visual C++,the second exploiting software kit provided by Pro/ENGINEER and ANSYS GUI/APDL modeling patterns,an integration method of 3D CAD and CAE is achieved,which includes regeneration of 3D parametric model,synchronous updating and analysis of FEA model. As in Browser/Server framework,the 3D CAD models of parts,components and the whole structure could also be displayed in the customer’s browser in VRML format.展开更多
The frequent occurrence of seismic events in Italy poses a strategic problem that involves either the culture of preservation of historical heritage or the civil protection action aimed to reduce the risk to people an...The frequent occurrence of seismic events in Italy poses a strategic problem that involves either the culture of preservation of historical heritage or the civil protection action aimed to reduce the risk to people and goods(buildings,bridges,dams,slopes,etc.).Most of the Italian architectural heritage is vulnerable to earthquakes,identifying the vulnerability as the inherent predisposition of the masonry building to suffer damage and collapse during an earthquake.In fact,the structural concept prevailing in these ancient masonry buildings is aimed at ensuring prevalent resistance to vertical gravity loads.Rarely do these ancient masonry structures offer relevant resistance to actions other than vertical ones and then they are intrinsically vulnerable to stresses induced by the earthquakes.One of the main technical activities carried out by the Civil Protection after an earthquake is to assess the damage in the buildings and to evaluate their own usability.Regarding historical buildings,ad-hoc synthetic forms,drafted in agreement between the Italian Civil Protection Department and the Ministry of Cultural Heritage and Activities and Tourism and based on visual inspection,are adopted by qualified technicians.In this paper,such activities are described and discussed along with the Italian Civil Protection System.However,given the complexity of the main technical activities to be performed after an earthquake there is a need for more accurate methods based on Structural Health Monitoring.展开更多
This project deals with architecture and engineering involved in the process of architectural design.Based on native irregular components,it aims at developing an innovative approach in the conception and rationalizat...This project deals with architecture and engineering involved in the process of architectural design.Based on native irregular components,it aims at developing an innovative approach in the conception and rationalization of non-standard structures.Contemporary architecture and its non-classical structures require the design of customized pieces.This process which is highly energy and resources consumptive does not always take into account the inherent material properties.This project develops a way of optimizing,in architectural structures,the use of native wood pieces that are not industrially transformed(e.g.boughs)or of reused pieces of carpentry.As a consequence,the ecological footprint of the structures would be reduced.展开更多
With the purpose of enhancing effective collaboration between architects and structural engineers in the building design field,an integration tool was developed for supporting information exchange from architectural m...With the purpose of enhancing effective collaboration between architects and structural engineers in the building design field,an integration tool was developed for supporting information exchange from architectural model to structural model.The PKPM(Bopomofo acronym,a Chinese building design software) structural model and an industry foundation classes(IFC) data model were adopted and analyzed to design the framework of the integration tool.The technique of mixed program languages(C++ and FORTRAN) was applied to developing the tool software,and the connectivity relationships and intersection nodes between the structural elements were optimized and simplified.A case study was implemented to illustrate the method to use the integration tool for information exchange from IFC-format architectural model to PKPM structural model.The results show that the tool can extract the information of architectural model and form a corresponding structural model.The presented method can help to enhance the modeling efficiency at the structural design phase.展开更多
Oxygen evolution reaction(OER)as the foremost stumbling block to generate cost-effective clean fuels has received extensive attention in recent years.But,it still maintains the challenge to manipulate the geometric an...Oxygen evolution reaction(OER)as the foremost stumbling block to generate cost-effective clean fuels has received extensive attention in recent years.But,it still maintains the challenge to manipulate the geometric and electronic structure during single reaction process under the same conditions.Herein,we report a simple self-template strategy to generate honeycomb-like Ni_(2)P/N,P-C hybrids with preferred electronic architecture.Experiments coupled with theoretical results revealed that the synthesized catalyst has two characteristics:firstly,the unique honeycomb-like morphology not only enables the fully utilization of catalytic active sites but also optimizes the mass/electron transportation pathway,which favor the diffusion of electrolyte to accessible active sites.Secondly,N,P-C substrate,on the one hand,largely contributes the electronic distribution near Fermi level(E_(F))thus boosting its electrical conductivity.On the other hand,the support effect result in the upshift of d-band center and electropositivity of Ni sites,which attenuates the energy barrier for the adsorption of OH~àand the formation of*OOH.In consequence,the optimized Ni_(2)P/N,P-C catalysts feature high electrocatalytic activity towards OER(a low overpotential of 252 m V to achieve10 m A cm^(-2))and 10 h long-term stability,the outstanding performance is comparable to most of transition metal catalysts.This work gives a innovative tactics for contriving original OER electrocatalysts,inspirng deeper understanding of fabricating catalysts by combining theoretical simulation and experiment design.展开更多
Architectural works,in the material form of buildings,are often perceived as cultural symbols and as works of art.However,today's architects have excessively seeked the artistic expression of building skins,and ig...Architectural works,in the material form of buildings,are often perceived as cultural symbols and as works of art.However,today's architects have excessively seeked the artistic expression of building skins,and ignored the architectural aesthetics represented by the structural system as a building skeleton and the elaboration of aesthetics of the architecture itself.Authors of this paper showed the compatibility of architectural presentation and structural design by interpreting the interaction between them,and proposed that a building is a building structure,and the building structure is the building.展开更多
Iranian traditional architecture can be identified in many of its old famous buildings in the country. The principles and specifications in these buildings show the intelligence of implemented techniques that make the...Iranian traditional architecture can be identified in many of its old famous buildings in the country. The principles and specifications in these buildings show the intelligence of implemented techniques that make them remain sustainable and energy efficient. Thus, it is important to explore the traditional structures and architectural technologies in order to understand the reasons for this sustainability toward the new methods in modern architecture. Many of historical buildings in Iran have remained standing after many years and they show the deep wisdom of their architects. The purpose of this article is studying the various aspects of traditional structure and integration between this well-oriented structure and architecture towards energy efficient sustainable buildings. For reaching this goal, we refer to Tekye-Amir-Chakhmagh in Yazd as our case study, which is one of the most important and noticeable examples of Iranian traditional architecture. By introducing Amir-Chakhmagh Complex, we analyzed the specifications and fundamental elements that played an important role in stability and sustainability of Tekye-Amir-Chakhmagh and thereafter, we assessed the technologies that were used intelligently and intricately in this historical building. In this research, information is collected with field study and library resources. Finally, qualities and characteristics of the structure are studied by drawings and structural analysis and as conclusion, the suggestions and guidelines are presented.展开更多
Structural design is an important component of architectural engineering.BIM is integrated into structural design to form a complete,linked,and information-based data platform.Therefore,in line with the features of BI...Structural design is an important component of architectural engineering.BIM is integrated into structural design to form a complete,linked,and information-based data platform.Therefore,in line with the features of BIM,such as interaction and coordination,information integration,as well as data simulation,this study analyzes the advantages of BIM in architectural structural design,proposes several optimization measures using BIM for architectural structural design,and promotes the rationality of architectural structural design.展开更多
Reactions of NaAcebiim (NaAcebiim = 1-acetic acid-2, 2'-biimidazote monoso- dium salt) and cadmium or zinc nitrate produce two supramolecular architectures, namely, 1D [Cd(Acebiim)(NO3)(H20)]n (1) and 0D [Z...Reactions of NaAcebiim (NaAcebiim = 1-acetic acid-2, 2'-biimidazote monoso- dium salt) and cadmium or zinc nitrate produce two supramolecular architectures, namely, 1D [Cd(Acebiim)(NO3)(H20)]n (1) and 0D [Zn(Acebiim)2(H20)2]'2H20 (2) in acidic aqueous solutions. Single-crystal X-ray diffraction analysis reveals that complex 1 crystallizes in the triclinic system, space group Pi, and 2 is of monoclinic system, space group P2 1/n. In 1, two nitrate groups link two Cd(Ⅱ) ions forming [Cd2(NO3)2(H20)2] as secondary building units that are interconnected by the Acebiim ligand into an infinite ladder. In2, the hydrogen-bonded synthon R22(16) between the N-H moieties and carboxylic acid link [Zn(Acebiim)2(H20)2], generating a 1D-extended ribbon. Moreover, hydrogen bonds and π-π interactions further stabilize the 3D supramolecular architecture.展开更多
This paper, for the first time, deals with a more systematic study of the structures in the Bohai petroliferous area that covers nearly one third of the Bohai Bay basin. The study mainly involves the effects of preexi...This paper, for the first time, deals with a more systematic study of the structures in the Bohai petroliferous area that covers nearly one third of the Bohai Bay basin. The study mainly involves the effects of preexisting basement faults on the basin formation, the characteristics of basin geometry and kinetics, the modelling of the tectonic-thermal history, the polycyclicity and heterogeneity in the structural evolution and the natural seismic tomographic images of the crust and upper mantle. The authors analyze the features of the dynamic evolution of the basin in the paper and point out that the basin in the Bohai petroliferous area is an extensional pull-apart basin.展开更多
An unusual two-dimensional supramolecular complex, namely, [Cd2(Cl)4(L)2](1), has been synthesized by 2-(1 H-imidazo[4,5-f][1,10]phenanthrolin-2-yl)phenol(L) and CdCl2·2.5H2O under hydrothermal conditio...An unusual two-dimensional supramolecular complex, namely, [Cd2(Cl)4(L)2](1), has been synthesized by 2-(1 H-imidazo[4,5-f][1,10]phenanthrolin-2-yl)phenol(L) and CdCl2·2.5H2O under hydrothermal conditions. The compound was characterized by elemental analysis, TG and single-crystal X-ray diffraction. It crystallizes in triclinic, space group P1 with a = 10.151(2), b = 14.119(3), c = 14.744(3) ?, α = 115.744(4), β = 108.063(4), γ = 93.371(4)o, V = 1762.7(7) A°^3, Z = 2, C(38)H(24)Cd2Cl4N8O2, Mr = 991.25, Dc = 1.868 g/cm^3, F(000) = 976, μ(Mo Ka) = 1.560 mm^-1, R = 0.0639 and w R = 0.1307. In 1, two Cd(II) atoms are bridged by two chroline atoms to give a dimer. Neighboring dimers are linked by N–H···Cl hydrogen bonds to afford supramolecular chains, which are further joined together by π-π interactions to result in a supramolecular layer. In addition, luminescent property and thermal behavior of compound 1 have been studied.展开更多
A novel Cd(Ⅱ) coordination polymer, [CdCI(Hpc)H2O]n (1, H2pc = 1H-pyrazole-3- carboxylic acid), was synthesized by the reaction of CdCl2·2.5H2O with H2pc, and structurally characterized by IR spectrum, UV-...A novel Cd(Ⅱ) coordination polymer, [CdCI(Hpc)H2O]n (1, H2pc = 1H-pyrazole-3- carboxylic acid), was synthesized by the reaction of CdCl2·2.5H2O with H2pc, and structurally characterized by IR spectrum, UV-Vis spectrum, elemental analysis, single-crystal X-ray diffraction, as well as thermal analysis. Compound 1 crystallizes in monoclinic, P21/n space group with α = 7.0304(3), b = 10.3047(3), c = 10.6446(4) A, β= 107.174(4)°, F = 736.78(5) A^3, Z = 4, C4HsCdClN2O3, Mr = 276.95, Dc = 2.497 g/cm%3, F(000) = 528.0,μ= 3.281 mm^-1, R = 0.0169 and wR = 0.0387. The central metals adopt distorted octahedral geometry. Carboxyl groups of the ligand connect Cd(Ⅱ) into a one-dimensional chain, which further constructs a two-dimensional network by halogen bridging. Such two-dimensional structures are finally connected into a three-dimensional supramolecular architecture due to the hydrogen bonds and intermolecular π…π interactions. In addition, complex 1 has high thermal stability.展开更多
Background:Species-specific genotypic features,local neighbourhood interactions and resource supply strongly influence the tree stature and growth rate.In mixed-species forests,diversity-mediated biomass allocation ha...Background:Species-specific genotypic features,local neighbourhood interactions and resource supply strongly influence the tree stature and growth rate.In mixed-species forests,diversity-mediated biomass allocation has been suggested to be a fundamental mechanism underlying the positive biodiversity-productivity relationships.Empirical evidence,however,is rare about the impact of local neighbourhood diversity on tree characteristics analysed at a very high level of detail.To address this issue we analysed these effects on the individual-tree crown architecture and tree productivity in a mature mixed forest in northern Germany.Methods:Our analysis considers multiple target tree species across a local neighbourhood species richness gradient ranging from 1 to 4.We applied terrestrial laser scanning to quantify a large number of individual mature trees(N=920)at very high accuracy.We evaluated two different neighbour inclusion approaches by analysing both a fixed radius selection procedure and a selection based on overlapping crowns.Results and conclusions:We show that local neighbourhood species diversity significantly increases crown dimension and wood volume of target trees.Moreover,we found a size-dependency of diversity effects on tree productivity(basal area and wood volume increment)with positive effects for large-sized trees(diameter at breast height(DBH)>40 cm)and negative effects for small-sized(DBH<40 cm)trees.In our analysis,the neighbour inclusion approach has a significant impact on the outcome.For scientific studies and the validation of growth models we recommend a neighbour selection by overlapping crowns,because this seems to be the relevant scale at which local neighbourhood interactions occur.Because local neighbourhood diversity promotes individual-tree productivity in mature European mixed-species forests,we conclude that a small-scale species mixture should be considered in management plans.展开更多
An essential step for the realization of free-form surface structures is to create an efficient structural gird that satisfies not only the architectural aesthetics,but also the structural performance.Employing the ma...An essential step for the realization of free-form surface structures is to create an efficient structural gird that satisfies not only the architectural aesthetics,but also the structural performance.Employing the main stress trajectories as the representation of force flows on a free-form surface,an automatic grid generation approach is proposed for the architectural design.The algorithm automatically plots the main stress trajectories on a 3D free-form surface,and adopts a modified advancing front meshing technique to generate the structural grid.Based on the proposed algorithm,an automatic grid generator named "St-Surmesh" is developed for the practical architectural design of free-form surface structure.The surface geometry of one of the Sun Valleys in Expo Axis for the Expo Shanghai 2010 is selected as a numerical example for validating the proposed approach.Comparative studies are performed to demonstrate how different structural grids affect the design of a free-form surface structure.展开更多
Under the requirement of everything over IP, network service shows the following characteristics:(1) network service increases its richness;(2) broadband streaming media becomes the mainstream. To achieve unified mult...Under the requirement of everything over IP, network service shows the following characteristics:(1) network service increases its richness;(2) broadband streaming media becomes the mainstream. To achieve unified multi-service bearing in the IP network, the largescale access convergence network architecture is proposed. This flat access convergence structure with ultra-small hops, which shortens the service transmission path, reduces the complexity of the edge of the network, and achieves IP strong waist model with the integration of computation, storage and transmission. The key technologies are also introduced in this paper, including endto-end performance guarantee for real time interactive services, fog storing mechanism, and built-in safety transmission with integration of aggregation and control.展开更多
A study has been made about the structural attribute of the NNW-trendingShizikou linear image belt in the head area of the reservoir of the Yangtze River Gorges and theevaluation of its crustal stability. On the basis...A study has been made about the structural attribute of the NNW-trendingShizikou linear image belt in the head area of the reservoir of the Yangtze River Gorges and theevaluation of its crustal stability. On the basis of regional geological surveys and by making astructural analysis and a multidisciplinary study, it has been ascertained that the segment withthe best displayed image characteristics is marked by a gravity gliding structure with a multilay-er gliding fold type architecture. This paper also analyzes the medium conditions, slope struc-ture and dynamic setting for the formation of the structure system.展开更多
基金Supported by Shanghai Leading Academic Discipline Project ,Project Number :T0601
文摘3D digital design for cranes’ structures based on hybrid software architecture of Client/Server and Browser/Server is introduced in this paper. Based on Pro/ENGINEER platform,3D parametric model family is built to allow generation of feasible configurations of cranes’ structures in Client/Server framework. Taking use of Visual C++,the second exploiting software kit provided by Pro/ENGINEER and ANSYS GUI/APDL modeling patterns,an integration method of 3D CAD and CAE is achieved,which includes regeneration of 3D parametric model,synchronous updating and analysis of FEA model. As in Browser/Server framework,the 3D CAD models of parts,components and the whole structure could also be displayed in the customer’s browser in VRML format.
文摘The frequent occurrence of seismic events in Italy poses a strategic problem that involves either the culture of preservation of historical heritage or the civil protection action aimed to reduce the risk to people and goods(buildings,bridges,dams,slopes,etc.).Most of the Italian architectural heritage is vulnerable to earthquakes,identifying the vulnerability as the inherent predisposition of the masonry building to suffer damage and collapse during an earthquake.In fact,the structural concept prevailing in these ancient masonry buildings is aimed at ensuring prevalent resistance to vertical gravity loads.Rarely do these ancient masonry structures offer relevant resistance to actions other than vertical ones and then they are intrinsically vulnerable to stresses induced by the earthquakes.One of the main technical activities carried out by the Civil Protection after an earthquake is to assess the damage in the buildings and to evaluate their own usability.Regarding historical buildings,ad-hoc synthetic forms,drafted in agreement between the Italian Civil Protection Department and the Ministry of Cultural Heritage and Activities and Tourism and based on visual inspection,are adopted by qualified technicians.In this paper,such activities are described and discussed along with the Italian Civil Protection System.However,given the complexity of the main technical activities to be performed after an earthquake there is a need for more accurate methods based on Structural Health Monitoring.
文摘This project deals with architecture and engineering involved in the process of architectural design.Based on native irregular components,it aims at developing an innovative approach in the conception and rationalization of non-standard structures.Contemporary architecture and its non-classical structures require the design of customized pieces.This process which is highly energy and resources consumptive does not always take into account the inherent material properties.This project develops a way of optimizing,in architectural structures,the use of native wood pieces that are not industrially transformed(e.g.boughs)or of reused pieces of carpentry.As a consequence,the ecological footprint of the structures would be reduced.
基金Project(2006BAJ01B01-01) supported by the National Key Technologies R&D Program of China during the 11th Five-Year Plan Period
文摘With the purpose of enhancing effective collaboration between architects and structural engineers in the building design field,an integration tool was developed for supporting information exchange from architectural model to structural model.The PKPM(Bopomofo acronym,a Chinese building design software) structural model and an industry foundation classes(IFC) data model were adopted and analyzed to design the framework of the integration tool.The technique of mixed program languages(C++ and FORTRAN) was applied to developing the tool software,and the connectivity relationships and intersection nodes between the structural elements were optimized and simplified.A case study was implemented to illustrate the method to use the integration tool for information exchange from IFC-format architectural model to PKPM structural model.The results show that the tool can extract the information of architectural model and form a corresponding structural model.The presented method can help to enhance the modeling efficiency at the structural design phase.
基金supported by the Major Science and Technology Program for Water Pollution Control and Treatment(2017ZX07402001)the Ministry of Science and Technology of China for their financial support and the associated project is the Key Program for International S&T Cooperation Projects(No.2018YFE0124600)。
文摘Oxygen evolution reaction(OER)as the foremost stumbling block to generate cost-effective clean fuels has received extensive attention in recent years.But,it still maintains the challenge to manipulate the geometric and electronic structure during single reaction process under the same conditions.Herein,we report a simple self-template strategy to generate honeycomb-like Ni_(2)P/N,P-C hybrids with preferred electronic architecture.Experiments coupled with theoretical results revealed that the synthesized catalyst has two characteristics:firstly,the unique honeycomb-like morphology not only enables the fully utilization of catalytic active sites but also optimizes the mass/electron transportation pathway,which favor the diffusion of electrolyte to accessible active sites.Secondly,N,P-C substrate,on the one hand,largely contributes the electronic distribution near Fermi level(E_(F))thus boosting its electrical conductivity.On the other hand,the support effect result in the upshift of d-band center and electropositivity of Ni sites,which attenuates the energy barrier for the adsorption of OH~àand the formation of*OOH.In consequence,the optimized Ni_(2)P/N,P-C catalysts feature high electrocatalytic activity towards OER(a low overpotential of 252 m V to achieve10 m A cm^(-2))and 10 h long-term stability,the outstanding performance is comparable to most of transition metal catalysts.This work gives a innovative tactics for contriving original OER electrocatalysts,inspirng deeper understanding of fabricating catalysts by combining theoretical simulation and experiment design.
文摘Architectural works,in the material form of buildings,are often perceived as cultural symbols and as works of art.However,today's architects have excessively seeked the artistic expression of building skins,and ignored the architectural aesthetics represented by the structural system as a building skeleton and the elaboration of aesthetics of the architecture itself.Authors of this paper showed the compatibility of architectural presentation and structural design by interpreting the interaction between them,and proposed that a building is a building structure,and the building structure is the building.
文摘Iranian traditional architecture can be identified in many of its old famous buildings in the country. The principles and specifications in these buildings show the intelligence of implemented techniques that make them remain sustainable and energy efficient. Thus, it is important to explore the traditional structures and architectural technologies in order to understand the reasons for this sustainability toward the new methods in modern architecture. Many of historical buildings in Iran have remained standing after many years and they show the deep wisdom of their architects. The purpose of this article is studying the various aspects of traditional structure and integration between this well-oriented structure and architecture towards energy efficient sustainable buildings. For reaching this goal, we refer to Tekye-Amir-Chakhmagh in Yazd as our case study, which is one of the most important and noticeable examples of Iranian traditional architecture. By introducing Amir-Chakhmagh Complex, we analyzed the specifications and fundamental elements that played an important role in stability and sustainability of Tekye-Amir-Chakhmagh and thereafter, we assessed the technologies that were used intelligently and intricately in this historical building. In this research, information is collected with field study and library resources. Finally, qualities and characteristics of the structure are studied by drawings and structural analysis and as conclusion, the suggestions and guidelines are presented.
文摘Structural design is an important component of architectural engineering.BIM is integrated into structural design to form a complete,linked,and information-based data platform.Therefore,in line with the features of BIM,such as interaction and coordination,information integration,as well as data simulation,this study analyzes the advantages of BIM in architectural structural design,proposes several optimization measures using BIM for architectural structural design,and promotes the rationality of architectural structural design.
基金supported by the National Natural Science Foundation of China(No.#21003125,21073190)the Natural Science Foundation of Fujian Province(2010 J01057)
文摘Reactions of NaAcebiim (NaAcebiim = 1-acetic acid-2, 2'-biimidazote monoso- dium salt) and cadmium or zinc nitrate produce two supramolecular architectures, namely, 1D [Cd(Acebiim)(NO3)(H20)]n (1) and 0D [Zn(Acebiim)2(H20)2]'2H20 (2) in acidic aqueous solutions. Single-crystal X-ray diffraction analysis reveals that complex 1 crystallizes in the triclinic system, space group Pi, and 2 is of monoclinic system, space group P2 1/n. In 1, two nitrate groups link two Cd(Ⅱ) ions forming [Cd2(NO3)2(H20)2] as secondary building units that are interconnected by the Acebiim ligand into an infinite ladder. In2, the hydrogen-bonded synthon R22(16) between the N-H moieties and carboxylic acid link [Zn(Acebiim)2(H20)2], generating a 1D-extended ribbon. Moreover, hydrogen bonds and π-π interactions further stabilize the 3D supramolecular architecture.
文摘This paper, for the first time, deals with a more systematic study of the structures in the Bohai petroliferous area that covers nearly one third of the Bohai Bay basin. The study mainly involves the effects of preexisting basement faults on the basin formation, the characteristics of basin geometry and kinetics, the modelling of the tectonic-thermal history, the polycyclicity and heterogeneity in the structural evolution and the natural seismic tomographic images of the crust and upper mantle. The authors analyze the features of the dynamic evolution of the basin in the paper and point out that the basin in the Bohai petroliferous area is an extensional pull-apart basin.
基金Supported by the National Natural Science Foundation of China(No.21607051)
文摘An unusual two-dimensional supramolecular complex, namely, [Cd2(Cl)4(L)2](1), has been synthesized by 2-(1 H-imidazo[4,5-f][1,10]phenanthrolin-2-yl)phenol(L) and CdCl2·2.5H2O under hydrothermal conditions. The compound was characterized by elemental analysis, TG and single-crystal X-ray diffraction. It crystallizes in triclinic, space group P1 with a = 10.151(2), b = 14.119(3), c = 14.744(3) ?, α = 115.744(4), β = 108.063(4), γ = 93.371(4)o, V = 1762.7(7) A°^3, Z = 2, C(38)H(24)Cd2Cl4N8O2, Mr = 991.25, Dc = 1.868 g/cm^3, F(000) = 976, μ(Mo Ka) = 1.560 mm^-1, R = 0.0639 and w R = 0.1307. In 1, two Cd(II) atoms are bridged by two chroline atoms to give a dimer. Neighboring dimers are linked by N–H···Cl hydrogen bonds to afford supramolecular chains, which are further joined together by π-π interactions to result in a supramolecular layer. In addition, luminescent property and thermal behavior of compound 1 have been studied.
基金supported by the National Natural Science Foundation of China(No.20801012)New Energy Technology Co.Ltd.of Ai Naji of Jiangsu Province(No.8507040091)
文摘A novel Cd(Ⅱ) coordination polymer, [CdCI(Hpc)H2O]n (1, H2pc = 1H-pyrazole-3- carboxylic acid), was synthesized by the reaction of CdCl2·2.5H2O with H2pc, and structurally characterized by IR spectrum, UV-Vis spectrum, elemental analysis, single-crystal X-ray diffraction, as well as thermal analysis. Compound 1 crystallizes in monoclinic, P21/n space group with α = 7.0304(3), b = 10.3047(3), c = 10.6446(4) A, β= 107.174(4)°, F = 736.78(5) A^3, Z = 4, C4HsCdClN2O3, Mr = 276.95, Dc = 2.497 g/cm%3, F(000) = 528.0,μ= 3.281 mm^-1, R = 0.0169 and wR = 0.0387. The central metals adopt distorted octahedral geometry. Carboxyl groups of the ligand connect Cd(Ⅱ) into a one-dimensional chain, which further constructs a two-dimensional network by halogen bridging. Such two-dimensional structures are finally connected into a three-dimensional supramolecular architecture due to the hydrogen bonds and intermolecular π…π interactions. In addition, complex 1 has high thermal stability.
基金LG was funded by the German Research Foundation(DFG 320926971)through the project“Analysis of diversity effects on above-groundproductivity in forests:advancing the mechanistic understanding of spatiotemporal dynamics in canopy space filling using mobile laser scanning”。
文摘Background:Species-specific genotypic features,local neighbourhood interactions and resource supply strongly influence the tree stature and growth rate.In mixed-species forests,diversity-mediated biomass allocation has been suggested to be a fundamental mechanism underlying the positive biodiversity-productivity relationships.Empirical evidence,however,is rare about the impact of local neighbourhood diversity on tree characteristics analysed at a very high level of detail.To address this issue we analysed these effects on the individual-tree crown architecture and tree productivity in a mature mixed forest in northern Germany.Methods:Our analysis considers multiple target tree species across a local neighbourhood species richness gradient ranging from 1 to 4.We applied terrestrial laser scanning to quantify a large number of individual mature trees(N=920)at very high accuracy.We evaluated two different neighbour inclusion approaches by analysing both a fixed radius selection procedure and a selection based on overlapping crowns.Results and conclusions:We show that local neighbourhood species diversity significantly increases crown dimension and wood volume of target trees.Moreover,we found a size-dependency of diversity effects on tree productivity(basal area and wood volume increment)with positive effects for large-sized trees(diameter at breast height(DBH)>40 cm)and negative effects for small-sized(DBH<40 cm)trees.In our analysis,the neighbour inclusion approach has a significant impact on the outcome.For scientific studies and the validation of growth models we recommend a neighbour selection by overlapping crowns,because this seems to be the relevant scale at which local neighbourhood interactions occur.Because local neighbourhood diversity promotes individual-tree productivity in mature European mixed-species forests,we conclude that a small-scale species mixture should be considered in management plans.
基金Project(51378457)supported by the National Natural Science Foundation of China
文摘An essential step for the realization of free-form surface structures is to create an efficient structural gird that satisfies not only the architectural aesthetics,but also the structural performance.Employing the main stress trajectories as the representation of force flows on a free-form surface,an automatic grid generation approach is proposed for the architectural design.The algorithm automatically plots the main stress trajectories on a 3D free-form surface,and adopts a modified advancing front meshing technique to generate the structural grid.Based on the proposed algorithm,an automatic grid generator named "St-Surmesh" is developed for the practical architectural design of free-form surface structure.The surface geometry of one of the Sun Valleys in Expo Axis for the Expo Shanghai 2010 is selected as a numerical example for validating the proposed approach.Comparative studies are performed to demonstrate how different structural grids affect the design of a free-form surface structure.
基金supported by The National Key Technology R&D Program (Grant No. 2011BAH19B00)The National Basic Research Program of China (973) (Grant No. 2012CB315900)The National High Technology Research and Development Program of China (863) (Grant No. 2015AA016102)
文摘Under the requirement of everything over IP, network service shows the following characteristics:(1) network service increases its richness;(2) broadband streaming media becomes the mainstream. To achieve unified multi-service bearing in the IP network, the largescale access convergence network architecture is proposed. This flat access convergence structure with ultra-small hops, which shortens the service transmission path, reduces the complexity of the edge of the network, and achieves IP strong waist model with the integration of computation, storage and transmission. The key technologies are also introduced in this paper, including endto-end performance guarantee for real time interactive services, fog storing mechanism, and built-in safety transmission with integration of aggregation and control.
基金This study was a contribution to Water conservancy Project 16-2-1 of the Seventh Five-Year Plan(1985-1989),entruated by the Surveying Bureau of rhe Committee of Water Resources of the Changjiang(Yangetze)River.
文摘A study has been made about the structural attribute of the NNW-trendingShizikou linear image belt in the head area of the reservoir of the Yangtze River Gorges and theevaluation of its crustal stability. On the basis of regional geological surveys and by making astructural analysis and a multidisciplinary study, it has been ascertained that the segment withthe best displayed image characteristics is marked by a gravity gliding structure with a multilay-er gliding fold type architecture. This paper also analyzes the medium conditions, slope struc-ture and dynamic setting for the formation of the structure system.