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Study Correlation between Physical-Mineralogical Properties of Sandstone Used in Ptolemaic Temples in Upper Egypt and Its Weathering Resistance
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作者 Essam H. Mohamed 《Journal of Minerals and Materials Characterization and Engineering》 CAS 2022年第5期371-384,共14页
This article focuses on study of a relation between physical-mineralogical properties of sandstone used in Ptolemaic temples in Upper Egypt and its resistance of deterioration factors affecting it. In the present stud... This article focuses on study of a relation between physical-mineralogical properties of sandstone used in Ptolemaic temples in Upper Egypt and its resistance of deterioration factors affecting it. In the present study, sandstone samples were collected from four sites;namely the temples of Dendera, Esna, Edfu and Kom Ombo which are located in Upper Egypt. Polarized light microscope (PLM), Scanning Electron Microscope (SEM), X-Ray diffraction (XRD) and energy-dispersive X-ray spectroscopy (EDX) were used to determine mineralogical properties, microstructure, and chemical compositions of the deteriorated sandstone samples, addition to physical properties tests;results of the study confirmed that sandstone samples containing a high percentage of salts, clay minerals and iron oxides have been significantly affected by deterioration factors. The deteriorated sandstone samples were treated by paraloid B72 3% enhanced with Nano silica 5% to improve the physical properties of stone. Results of the study indicated that the samples which were consolidated by Nanoparticles based on acrylic Copolymers (Paraloid B72 and its Nanocomposite with Nano silica) achieved the best results for improvement of its physical-mineralogical properties. This is the ultimate aim of the study for the purpose of conservation and sustainability of building materials of the temples. 展开更多
关键词 SANDSTONE Ptolemaic temples Physical-Mineralogical Properties Weathering Resistance of Sandstone Consolidation Materials
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Multifunctional Nacre‑Like Nanocomposite Papers for Electromagnetic Interference Shielding via Heterocyclic Aramid/MXene Template‑Assisted In‑Situ Polypyrrole Assembly
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作者 Jinhua Xiong Xu Zhao +6 位作者 Zonglin Liu He Chen Qian Yan Huanxin Lian Yunxiang Chen Qingyu Peng Xiaodong He 《Nano-Micro Letters》 SCIE EI CAS 2025年第3期37-54,共18页
Robust, ultra-flexible, and multifunctional MXene-basedelectromagnetic interference (EMI) shielding nanocomposite filmsexhibit enormous potential for applications in artificial intelligence,wireless telecommunication,... Robust, ultra-flexible, and multifunctional MXene-basedelectromagnetic interference (EMI) shielding nanocomposite filmsexhibit enormous potential for applications in artificial intelligence,wireless telecommunication, and portable/wearable electronic equipment.In this work, a nacre-inspired multifunctional heterocyclic aramid(HA)/MXene@polypyrrole (PPy) (HMP) nanocomposite paper withlarge-scale, high strength, super toughness, and excellent tolerance tocomplex conditions is fabricated through the strategy of HA/MXenehydrogel template-assisted in-situ assembly of PPy. Benefiting from the"brick-and-mortar" layered structure and the strong hydrogen-bondinginteractions among MXene, HA, and PPy, the paper exhibits remarkable mechanical performances, including high tensile strength (309.7 MPa),outstanding toughness (57.6 MJ m−3), exceptional foldability, and structural stability against ultrasonication. By using the template effect ofHA/MXene to guide the assembly of conductive polymers, the synthesized paper obtains excellent electronic conductivity. More importantly,the highly continuous conductive path enables the nanocomposite paper to achieve a splendid EMI shielding effectiveness (EMI SE) of 54.1 dBat an ultra-thin thickness (25.4 μm) and a high specific EMI SE of 17,204.7 dB cm2g−1. In addition, the papers also have excellent applicationsin electromagnetic protection, electro-/photothermal de-icing, thermal therapy, and fire safety. These findings broaden the ideas for developinghigh-performance and multifunctional MXene-based films with enormous application potential in EMI shielding and thermal management. 展开更多
关键词 MXene Remarkable mechanical properties Heterocyclic aramid Electromagnetic interference shielding POLYPYRROLE Multifunctionality
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Molecular simulation study of the microstructures and properties of pyridinium ionic liquid[HPy][BF_(4)]mixed with acetonitrile
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作者 XU Jian-Qiang MA Zhao-Peng +2 位作者 CHENG Si LIU Zhi-Cong ZHU Guang-Lai 《原子与分子物理学报》 CAS 北大核心 2025年第4期27-32,共6页
The microstructures and thermodynamic properties of mixed systems comprising pyridinium ionic liquid[HPy][BF_(4)]and acetonitrile at different mole fractions were studied using molecular dynamics simulation in this wo... The microstructures and thermodynamic properties of mixed systems comprising pyridinium ionic liquid[HPy][BF_(4)]and acetonitrile at different mole fractions were studied using molecular dynamics simulation in this work.The following properties were determined:density,self-diffusion coefficient,excess molar volume,and radial distribution function.The results show that with an increase in the mole fraction of[HPy][BF_(4)],the self-diffusion coefficient decreases.Additionally,the excess molar volume initially decreases,reaches a minimum,and then increases.The rules of radial distribution functions(RDFs)of characteristic atoms are different.With increasing the mole fraction of[HPy][BF_(4)],the first peak of the RDFs of HA1-F decreases,while that of CT6-CT6 rises at first and then decreases.This indicates that the solvent molecules affect the polar and non-polar regions of[HPy][BF_(4)]differently. 展开更多
关键词 Pyridinium ionic liquids Thermodynamic properties Molecular dynamics simulation Radial distribution functions
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Research on the Construction of Intellectual Property System and Optimization of Business Environment in China
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作者 Zhang Xue Lyu Guofu 《科技与法律(中英文)》 2025年第1期125-137,共13页
With the rapid development of globalization and information technology,intellectual property has been one of the key drivers of economic growth,and the construction of intellectual property system has become an import... With the rapid development of globalization and information technology,intellectual property has been one of the key drivers of economic growth,and the construction of intellectual property system has become an important criterion for measuring the quality of business environment.This article is intended to explore the current status of intellectual property system construction in China,the challenges,and its relationship with the business environment,to propose the corresponding countermeasures and suggestions.The study finds that the legal system of intellectual property in China is gradually improving,and judicial and administrative protection are continuously strengthened.However,the challenges still remain such as frequent infringements,rights hard to protect and insufficient international cooperation.These issues not only affect the legitimate rights and interests of innovation entities,but also for the market fairness and the level of the business environment.Therefore,this article proposes that strengthening the perfection of the intellectual property legal system,enhancing intellectual property services and support capabilities,strengthening international cooperation and exchanges,and accelerating the cultivation of composite talents.It aims to provide theoretical references for the construction of intellectual property system and the optimization of the business environment,promote the high-quality development of economy and enhance the global competitiveness of the country. 展开更多
关键词 intellectual property business environment system construction economic development
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Preparation and magnetic properties of Fe_2O_3 microtubules prepared by sol-gel template method 被引量:2
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作者 CHANG Chuanbo ZHANG Cunrui +1 位作者 WANG Wenyan LI Qiaoling 《Rare Metals》 SCIE EI CAS CSCD 2010年第5期501-504,共4页
Fe(OH)3 precursor sol was prepared by a sol-gel method. The precursor sol was dipped onto the absorbent cotton, and gel was formed on the absorbent cotton template after the volatilization of moisture. Fe2O3 microtu... Fe(OH)3 precursor sol was prepared by a sol-gel method. The precursor sol was dipped onto the absorbent cotton, and gel was formed on the absorbent cotton template after the volatilization of moisture. Fe2O3 microtubules were synthesized after the process of self-propagation or calcination. The phase, morphology, and particle diameter of the samples were examined by X-ray diffraction (XRD) and scanning electron microscopy (SEM), and the magnetic properties of the samples were measured using a vibrating sample magnetometer (VSM). The external diameters of Fe2O3 microtubules ranged between 8 and 13 μm, and the wall thicknesses ranged between 0.5 and 2 μm. The type of the calcination method plays a significant role in developing the Fe2O3 phase and the variation in the magnetic properties in the sol-gel template complexing method. γ-Fe2O3 was synthesized by a self-propagation method. However, α-Fe203 was synthesized after calcination at 400℃ for 2 h. The coercivity of the samples synthesized by calcination at 400℃ for 2 h after self-propagation was found to increase significantly, thereby presenting hard magnetic properties. 展开更多
关键词 inorganic compounds iron oxides MICROTUBULES sol-gel process magnetic properties
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3D Finite Elements Technique for Collapse Causes of the Pylons in Egyptian Temples: A Study of the Great Pylon of Ramesseum Temple, Luxor, Egypt 被引量:1
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作者 Essam H. Mohamed 《Open Journal of Geology》 2019年第13期1022-1041,共20页
This research presents damage causes of the pylons in the ancient Egyptian temples based on 3D finite elements analysis. The main purpose of the research determines the failure causes of the first pylon of the Ramessi... This research presents damage causes of the pylons in the ancient Egyptian temples based on 3D finite elements analysis. The main purpose of the research determines the failure causes of the first pylon of the Ramessium temple, which is situated in Upper Egypt, at Luxor “Thebes” on the west bank of the Nile River. The first pylon of Ramessium temple subjected to seismic activity effects on long term, combined with several structural damage factors such as the defects resulting from the construction technique, where the builder used the poor quality of stones in foundations of the pylon, the building materials residue was used as filler for the core of the pylon walls, and it lacked vertical joints between the courses. In addition to it founded on alluvial soil that is vulnerable to contaminated water, it is still suffering damage factors and urban trespasses at the moment. All of the former factors helped the pylon to be affected by the earthquakes loads that occurred on it. The structural behavior of the pylon under self-weight and earthquakes loads were carried out by Numerical analysis to find out the loads and stresses which caused collapsing of the pylon. Results of the study indicated that the pylon subjected to a horizontal displacement due to old earthquakes force, led to collapse of the pylon. Finally, the study represents use of modern technique to study the structural behavior of the most important architectural units in ancient Egyptian temples to identify the causes of its collapse. 展开更多
关键词 The GREAT PYLON of Ramessium templE Collapse Causes 3D Finite Elements Numerical Models Horizontal and Vertical Displacement
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Template synthesis and adsorption properties of chitosan salicylal Schiff bases 被引量:3
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作者 曹佐英 魏琦峰 张启修 《Journal of Central South University of Technology》 2004年第2期169-172,共4页
To improve the adsorption properties of chemically modified chitosan, the chelating resin of salicylal chitosan Schiff bases was prepared by the template cross-linking method using Cu(Ⅱ) as template ion and ethylen... To improve the adsorption properties of chemically modified chitosan, the chelating resin of salicylal chitosan Schiff bases was prepared by the template cross-linking method using Cu(Ⅱ) as template ion and ethylene glycol bisglycidyl ether as cross-linking agent in microwave, and was characterized by IR. The adsorption capacity and selectivity coefficient of the chemically modified chitosan for Cu(Ⅱ), Fe(Ⅲ) and Zn(Ⅱ) were investigated, respectively. The results show that the adsorption capacity of the resin 2.73 mmol/g for Cu(Ⅱ) is bigger than that for other two metal ions, 0.22 mmol/g for Fe(Ⅲ), and 0.42 mmol/g for Zn(Ⅱ), and the selectivity coefficients are as follows: KCu(Ⅱ)/Fe(Ⅲ)=12.4, KCu(Ⅱ)/Zn(Ⅱ)=6.5. 展开更多
关键词 microwave irradiation template synthesis chelating resin adsorption property
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Properties and Characteristics of Regolith-Based Materials for Extraterrestrial Construction 被引量:2
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作者 Cheng Zhou Yuyue Gao +4 位作者 Yan Zhou Wei She Yusheng Shi Lieyun Ding Changwen Miao 《Engineering》 SCIE EI CAS CSCD 2024年第6期159-181,共23页
The construction of extraterrestrial bases has become a new goal in the active exploration of deep space.Among the construction techniques,in situ resource-based construction is one of the most promising because of it... The construction of extraterrestrial bases has become a new goal in the active exploration of deep space.Among the construction techniques,in situ resource-based construction is one of the most promising because of its good sustainability and acceptable economic cost,triggering the development of various types of extraterrestrial construction materials.A comprehensive survey and comparison of materials from the perspective of performance was conducted to provide suggestions for material selection and optimization.Thirteen types of typical construction materials are discussed in terms of their reliability and applicability in extreme extraterrestrial environment.Mechanical,thermal and optical,and radiation-shielding properties are considered.The influencing factors and optimization methods for these properties are analyzed.From the perspective of material properties,the existing challenges lie in the comprehensive,long-term,and real characterization of regolith-based construction materials.Correspondingly,the suggested future directions include the application of high-throughput characterization methods,accelerated durability tests,and conducting extraterrestrial experiments. 展开更多
关键词 Extraterrestrial construction Characterization Mechanical property Thermal property Optical property Radiation-shielding
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Physical,mechanical and thermal properties of vacuum sintered HUST-1 lunar regolith simulant 被引量:2
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作者 Wenbin Han Yan Zhou +2 位作者 Lixiong Cai Cheng Zhou Lieyun Ding 《International Journal of Mining Science and Technology》 SCIE EI CAS CSCD 2024年第9期1243-1257,共15页
Establishing a base on the Moon is one of the new goals of human lunar exploration in recent years.Sintered lunar regolith is one of the most potential building materials for lunar bases.The physical,mechanical and th... Establishing a base on the Moon is one of the new goals of human lunar exploration in recent years.Sintered lunar regolith is one of the most potential building materials for lunar bases.The physical,mechanical and thermal properties of sintered lunar regolith are vital performance indices for the structural design of a lunar base and analysis of many critical mechanical and thermal issues.In this study,the HUST-1 lunar regolith simulant(HLRS)was sintered at 1030,1040,1050,1060,1070,and 1080℃.The effect of sintering temperature on the compressive strength was investigated,and the exact value of the optimum vacuum sintering temperature was determined between 1040 and 1060℃.Then,the microstructure and material composition of vacuum sintered HLRS at different temperatures were characterized.It was found that the sintering temperature has no significant effect on the mineral composition in the temperature range of 1030-1080℃.Besides,the heat capacity,thermal conductivity,and coefficient of thermal expansion(CTE)of vacuum sintered HLRS at different temperatures were investigated.Specific heat capacity of sintered samples increases with the increase of test temperature within the temperature range from-75 to 145℃.Besides,the thermal conductivity of the sintered sample is proportional to density.Finally,the two temperatures of 1040 and 1050℃were selected for a more detailed study of mechanical properties.The results showed that compressive strength of sintered sample is much higher than tensile strength.This study reveals the effects of sintering temperature on the physical,mechanical and thermal properties of vacuum sintered HLRS,and these material parameters will provide support for the construction of future lunar bases. 展开更多
关键词 Lunar base Lunar regolith simulant Vacuum sintering Physical properties Mechanical properties Thermal properties
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Study on Further Development of Temples in the Mount Tai from the Perspective of Experience Economy
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作者 CHEN Fangying 《Journal of Landscape Research》 2014年第6期41-42,共2页
From the perspective of experience economy, this paper proposed that traditional temple sightseeing has been unable to meet needs of tourists, temple cultural sites must pay more attention to visitors' experience ... From the perspective of experience economy, this paper proposed that traditional temple sightseeing has been unable to meet needs of tourists, temple cultural sites must pay more attention to visitors' experience in tourism development. On the basis of analyzing characteristics of temple cultures in the Mount Tai and problems in its tourism development, strategies for the development of temple cultures in the Mount Tai were given from the perspective of experience economy. 展开更多
关键词 Experience marketing templE Mount Tai STRATEGY
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Compared Study of Authentic Culture on Three Guangdong Ancestral Temples
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作者 Yifeng Wen 《World Journal of Engineering and Technology》 2017年第3期1-11,共11页
In this article, three Guangdong’s ancestral temples are taken as case studies to explore strategies for cultural heritage conservation. Heritage conservation is very important not only for our missing of past, but i... In this article, three Guangdong’s ancestral temples are taken as case studies to explore strategies for cultural heritage conservation. Heritage conservation is very important not only for our missing of past, but in order that our own cultural identity can be formed today. In China, different stakeholders hold various views on heritage protection and conflicts often take place. Particularly, many folk religion’s cultural heritages face a dangerous scenario and could even be damaged or destroyed for a variety of “reason”. This article tries to re-examine fundamental values and assessment criteria for cultural heritage conservation. The authenticity is a core concept involved with those of issues. Based on the views of culture place, the author puts forward the concept of “emic culture authenticity” as a hinge to explore authentic culture ecology of heritage and its model, to facilitate the cultural heritage conservation and reuse by the strategies of classification and adaptation. 展开更多
关键词 HERITAGE Conservation Ancestral templE FOLK RELIGION CULTURE AUTHENTICITY Adaptive Strategy
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Structures and Properties of PEDOT Nanotubes Prepared by a Template Synthesis Method
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作者 徐建华 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2009年第2期287-291,共5页
PEDOT nanotubes were prepared by a template synthesis method. Based on our template, it was deduced that there are two successive processes in the formation of nanotubes. The first step is soakage of the porous templa... PEDOT nanotubes were prepared by a template synthesis method. Based on our template, it was deduced that there are two successive processes in the formation of nanotubes. The first step is soakage of the porous templates by a polymer solution, and the second step is adsorption of free charged cationic groups and doped PEDOT onto the template surface with negative charges. XRD results showed that well orientated PEDOT chains were formed during the synthesis, moreover the arrange conductivity of molecular chains strongly affect the structures of PEDOT nanotubes. The nanotubes were measured to be about 5.5-17.6 S/cm, which is higher than that of nanotube pellet due to the high contact resistance between the adjacent nanotubes. 展开更多
关键词 PEDOT nanotube template synthesis method STRUCTURE property
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High-throughput calculations combining machine learning to investigate the corrosion properties of binary Mg alloys 被引量:4
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作者 Yaowei Wang Tian Xie +4 位作者 Qingli Tang Mingxu Wang Tao Ying Hong Zhu Xiaoqin Zeng 《Journal of Magnesium and Alloys》 SCIE EI CAS CSCD 2024年第4期1406-1418,共13页
Magnesium(Mg)alloys have shown great prospects as both structural and biomedical materials,while poor corrosion resistance limits their further application.In this work,to avoid the time-consuming and laborious experi... Magnesium(Mg)alloys have shown great prospects as both structural and biomedical materials,while poor corrosion resistance limits their further application.In this work,to avoid the time-consuming and laborious experiment trial,a high-throughput computational strategy based on first-principles calculations is designed for screening corrosion-resistant binary Mg alloy with intermetallics,from both the thermodynamic and kinetic perspectives.The stable binary Mg intermetallics with low equilibrium potential difference with respect to the Mg matrix are firstly identified.Then,the hydrogen adsorption energies on the surfaces of these Mg intermetallics are calculated,and the corrosion exchange current density is further calculated by a hydrogen evolution reaction(HER)kinetic model.Several intermetallics,e.g.Y_(3)Mg,Y_(2)Mg and La_(5)Mg,are identified to be promising intermetallics which might effectively hinder the cathodic HER.Furthermore,machine learning(ML)models are developed to predict Mg intermetallics with proper hydrogen adsorption energy employing work function(W_(f))and weighted first ionization energy(WFIE).The generalization of the ML models is tested on five new binary Mg intermetallics with the average root mean square error(RMSE)of 0.11 eV.This study not only predicts some promising binary Mg intermetallics which may suppress the galvanic corrosion,but also provides a high-throughput screening strategy and ML models for the design of corrosion-resistant alloy,which can be extended to ternary Mg alloys or other alloy systems. 展开更多
关键词 Mg intermetallics Corrosion property HIGH-THROUGHPUT Density functional theory Machine learning
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Preparation and Magnetic Properties of Cu-Ni Core-shell Nanowires in Ion-track Templates
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作者 陈永辉 DUAN Jinglai +4 位作者 YAO Huijun MO Dan WANG Tieshan SUN Youmei 刘杰 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2015年第4期665-669,共5页
Cu-Ni core-shell nanowires, with an inner Cu core diameter of about 60 nm and varying Ni shell thicknesses (10, 30, 50, 60, and 80 nm), were successfully fabricated in porous polycarbonate (PC) ion- track template... Cu-Ni core-shell nanowires, with an inner Cu core diameter of about 60 nm and varying Ni shell thicknesses (10, 30, 50, 60, and 80 nm), were successfully fabricated in porous polycarbonate (PC) ion- track templates by a two-step etching and electrodeposition method. In our experiment, the thickness of Ni shell can be effectively tuned through the etching time of templates. The core-shell structure was confirmed by scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The X-ray diffraction (XRD) pattern elucidates the co-existence of characteristic peaks for both Cu and Ni, indicating no other phases were formed during preparation. Magnetic hysteresis loops measured via vibrating sample magnetometry (VSM) revealed that Cu-Ni core-shell nanowires with thinner Ni shell exhibited obviously diamagnetic character and together with a weak ferromagnetic activity, whereas ferromagnetic behavior was primarily measured for the wires with thicker Ni shell. With increasing Ni shell thickness, the squareness and coercivity value became smaller due to the shape anisotropy and the formation of multi-domain structure. 展开更多
关键词 core-shell nanowires ion track template ETCHING ELECTRODEPOSITION magnetic property
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The Rapid Development of Technology in Making Iron Clamps of Three Ancient Temples in the Archaic and Classical Period
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作者 George Varoufakis 《Journal of Chemistry and Chemical Engineering》 2012年第12期1136-1141,共6页
A few years ago, the present author had the opportunity to study the iron clamps of the archaic and classical temples. This research led to very interesting results concerning the development of technology applied in ... A few years ago, the present author had the opportunity to study the iron clamps of the archaic and classical temples. This research led to very interesting results concerning the development of technology applied in making those clamps and what is more its rapid evolution in a very short period. For instance, the technology in making the clamps of Parthenon and those of the Epikourios Apollo differs completely, although the latter was erected by the same engineer, Iktinos. Actually, it is a revolutionary one as compared with that applied in the erection of Parthenon. The paper starts by examining the making of the archaic Trapeza iron clamps and continue with those of the Parthenon and the Epikourios Apollo. 展开更多
关键词 Iron clamps archaic temples classical temples development in technology macro micro examination.
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A review on the multi-scaled structures and mechanical/thermal properties of tool steels fabricated by laser powder bed fusion additive manufacturing 被引量:1
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作者 Huajing Zong Nan Kang +1 位作者 Zehao Qin Mohamed El Mansori 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2024年第5期1048-1071,共24页
The laser powder bed fusion(LPBF) process can integrally form geometrically complex and high-performance metallic parts that have attracted much interest,especially in the molds industry.The appearance of the LPBF mak... The laser powder bed fusion(LPBF) process can integrally form geometrically complex and high-performance metallic parts that have attracted much interest,especially in the molds industry.The appearance of the LPBF makes it possible to design and produce complex conformal cooling channel systems in molds.Thus,LPBF-processed tool steels have attracted more and more attention.The complex thermal history in the LPBF process makes the microstructural characteristics and properties different from those of conventional manufactured tool steels.This paper provides an overview of LPBF-processed tool steels by describing the physical phenomena,the microstructural characteristics,and the mechanical/thermal properties,including tensile properties,wear resistance,and thermal properties.The microstructural characteristics are presented through a multiscale perspective,ranging from densification,meso-structure,microstructure,substructure in grains,to nanoprecipitates.Finally,a summary of tool steels and their challenges and outlooks are introduced. 展开更多
关键词 additive manufacturing laser powder bed fusion tool steel multi-scaled structure mechanical properties thermal properties
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A Polymeric Iodiplumbate(Ⅱ) Templated by Conjugated Quaternary Ammonium:Synthesis,Band Structure and Optical Properties
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作者 成丽川 李浩宏 +3 位作者 陈之荣 李俊篯 黄长沧 蔡增良 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2007年第11期1315-1321,共7页
A new lead(Ⅱ) iodide coordination polymer [(npq)(PbI3)]n1 (npq = N-propyl- quinolinium) has been synthesized in the presence of npq as structure-directing reagent (SDA). Compound 1 crystallizes in the ortho... A new lead(Ⅱ) iodide coordination polymer [(npq)(PbI3)]n1 (npq = N-propyl- quinolinium) has been synthesized in the presence of npq as structure-directing reagent (SDA). Compound 1 crystallizes in the orthorhombic system, space group Pbca, with a = 19.158(4), b = 7.9909(16), c = 22.929(5) A, V = 3510.2(12) A3, Z = 8, Dc = 2.877 g/cm3, F(000) = 2672, C12H1413NPb, Mr= 760.14, μ(MoKα) = 14.872 mm-1, the final R = 0.0431 and wR = 0.1021 for 3678 observed reflections with Ⅰ 〉 2σ(Ⅰ). Structure determination indicates that the [PbI3]^-n infinite chains in each unit cell shape the sketch of 1, which could be described as the result of face-sharing distorted PbI6 octahedra running along the b axis. Electrostatic interaction between conjugated organic counter-cations and inorganic moieties presents and contributes to the crystal packing. 1 was further characterized with IR and elemental analysis. Based on the crystal structure data, quantum chemical calculation with DFT method was used to reveal the electronic structure and optical property of 1. 展开更多
关键词 coordination polymers lead iodide density of state optical property
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Tetrahedral framework nucleic acids/hyaluronic acidmethacrylic anhydride hybrid hydrogel with antimicrobial and anti-inflammatory properties for infected wound healing 被引量:1
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作者 Cai Qi Qiang Sun +4 位作者 Dexuan Xiao Mei Zhang Shaojingya Gao Bin Guo Yunfeng Lin 《International Journal of Oral Science》 SCIE CAS CSCD 2024年第3期436-447,共12页
Bacterial resistance and excessive inflammation are common issues that hinder wound healing.Antimicrobial peptides(AMPs)offer a promising and versatile antibacterial option compared to traditional antibiotics,with add... Bacterial resistance and excessive inflammation are common issues that hinder wound healing.Antimicrobial peptides(AMPs)offer a promising and versatile antibacterial option compared to traditional antibiotics,with additional anti-inflammatory properties.However,the applications of AMPs are limited by their antimicrobial effects and stability against bacterial degradation.TFNAs are regarded as a promising drug delivery platform that could enhance the antibacterial properties and stability of nanodrugs.Therefore,in this study,a composite hydrogel(HAMA/t-GL13K)was prepared via the photocross-linking method,in which tFNAs carry GL13K.The hydrogel was injectable,biocompatible,and could be instantly photocured.It exhibited broad-spectrum antibacterial and anti-inflammatory properties by inhibiting the expression of inflammatory factors and scavenging ROS.Thereby,the hydrogel inhibited bacterial infection,shortened the wound healing time of skin defects in infected skin full-thickness defect wound models and reduced scarring.The constructed HAMA/tFNA-AMPs hydrogels exhibit the potential for clinical use in treating microbial infections and promoting wound healing. 展开更多
关键词 properties. HYDROGEL ANHYDRIDE
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Effects of deformation temperatures on microstructures,aging behaviors and mechanical properties of Mg-Gd-Er-Zr alloys fabricated by hard-plate rolling 被引量:2
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作者 Ke Liu Dalong Hu +4 位作者 Feng Lou Zijian Yu Shubo Li Xian Du Wenbo Du 《Journal of Magnesium and Alloys》 SCIE EI CAS CSCD 2024年第6期2345-2359,共15页
In this investigation,a high-strength Mg-12Gd-1.0Er-0.5Zr(wt.%)alloy sheet was produced by hot extrusion(HE)and subsequent hard-plate rolling(HPR)at different temperatures.The results indicate that the microstructures... In this investigation,a high-strength Mg-12Gd-1.0Er-0.5Zr(wt.%)alloy sheet was produced by hot extrusion(HE)and subsequent hard-plate rolling(HPR)at different temperatures.The results indicate that the microstructures of these final-rolled sheets are inhomogeneous,mainly including coarse deformed grains and dynamic recrystallized(DRXed)grains,and the volume fraction of these coarse deformed grains increases as the rolling temperature increases.Thus,more DRXed grains can be found in R-385℃sheet,resulting in a smaller average grain size and weaker basal texture,while the biggest grains and the highest strong basal texture are present in R-450℃sheet.Amounts of dynamic precipitation ofβphases which are mainly determined by the rolling temperature are present in these sheets,and its precipitation can consume the content of Gd solutes in the matrix.As a result,the lowest number density ofβphase in R-450℃sheet is beneficial to modify the age hardening response.Thus,the R-450℃sheet displays the best age hardening response because of a severe traditional precipitation ofβ’(more)andβH/βM(less)precipitates,resulting in a sharp improvement in strength,i.e.ultimate tensile strength(UTS)of∼518±17 MPa and yield strength(YS)of∼438±18 MPa.However,the elongation(EL)of this sheet reduces greatly,and its value is∼2.7±0.3%.By contrasting,the EL of the peak-aging R-385℃sheet keeps better,changing from∼4.9±1.2%to∼4.8±1.4%due to a novel dislocation-induced chain-like precipitate which is helpful to keep good balance between strength and ductility. 展开更多
关键词 Mg-Gd-Er-Zr sheets Age hardening response PRECIPITATES Mechanical properties
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Hydrothermal Synthesis,Crystal Structure and Luminescent Properties of an Organically Templated 2-D Uranyl Sulfate
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作者 郭鸿旭 翁文 王庆华 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2008年第12期1455-1458,共4页
An organically templated 2-D uranyl sulfate, {(C2H8N)[(UO2)Cl(SO4)(H2O)] }n 1, has been hydrothermally synthesized. The crystal and molecular structures have been determined by X-ray crystallography method and... An organically templated 2-D uranyl sulfate, {(C2H8N)[(UO2)Cl(SO4)(H2O)] }n 1, has been hydrothermally synthesized. The crystal and molecular structures have been determined by X-ray crystallography method and spectral techniques. 1 belongs to monoclinic, space group P21/c with a = 8.3545(17), b = 10.550(2), c = 12.370(3)A, β = 102.64(3)°, V = 1063.9(4)A3, Mr = 464.64, De= 2.901 g/cm^3, F(000) = 836,μ = 15.710 mm^-1, Z= 4, the final R = 0.0286 and wR = 0.0685 for 10164 observed reflections with Ⅰ 〉 2σ(Ⅰ). 1 presents a two-dimensional layer-like structure constructed from infinite anionic [(UO2)Cl(H2O)(SO4)]^- layers with [C2H8N]^+ cations balancing the charge and a number of intermoleeular hydrogen bonds (C-H…O and O-H…Cl) existing in the solid state. The fluorescence properties of 1 have also been discussed. 展开更多
关键词 hydrothermal synthesis crystal structure fluorescence properties 2-D layer-like uranyl sulfate
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