Crystals of a new organometallic nonlinear optical （NLO） compound, di-ta-chloro-bis[chlorotri（thiourea）bismuth（Ⅲ）]- pentachloro（thiourea）bismuth-ate（Ⅲ） （DCBPB）, have been successfully grown from formic a...Crystals of a new organometallic nonlinear optical （NLO） compound, di-ta-chloro-bis[chlorotri（thiourea）bismuth（Ⅲ）]- pentachloro（thiourea）bismuth-ate（Ⅲ） （DCBPB）, have been successfully grown from formic acid aqueous solutions of thio-urea and bismuth chloride by a slow evaporation technique. The crystal structure and atomic composition of DCBPB have been confirmed by single crystal X-ray diffraction （SCXRD）, Fourier transform infrared spectra, and elemental analysis. The SCXRD results proved that DCBPB crystallizes in triclinic space group P1 with unit cell dimensions of a = 7.0606（2） A, b = 8.8106（4） A, c = 16.3247（8） A, a = 99.242（4）°, fl = 95.309（3）°, ）/= 105.856（3）°, and Z= 2. DCBPB crystal exhibits excel-lent transmittance from 500 to 2500 nm and green fluorescence with maximum emission at 508 nm. The thermogravimetric-differential scanning calorimetry （TG-DSC） analysis indicates that a solid-phase reaction took place at 170.1 ℃, whereas the decomposition temperature of the crystal material was 189℃. The NLO property obtained by the Kurtz powder test showed that the second harmonic generation efficiency of DCBPB crystal is two-seventh of KDP crystal.展开更多
In this context, traditional building crafts craftsman in artistic conception is under the control, use the appropriate tools or equipment, according to the ages, follow the way from raw material acquisition, manufact...In this context, traditional building crafts craftsman in artistic conception is under the control, use the appropriate tools or equipment, according to the ages, follow the way from raw material acquisition, manufacture components to install molding, to complete a post-renovation process technology ; endangered intangible cultural heritage in urgent need of rescue and system protection. In this paper, the current status of our architectural heritage protection process, analyzes the signi？ cance of the protection framework and ideas, discuss their research methods to analyze the feasibility of building process aimed at promoting heritage protection process, to resolve the current architectural Heritage Protection the “lost technology” and “craftsman team fault,” the urgent problem for protection policies provide reference formulation. On the building process is about building sophisticated cognitive system theory and principles and methods of generation, including the principle of building technology, building technology system structure, and evolution of construction technology paradigm, Chinese modern architecture and sophisticated analysis of the problem 4 to improve its strategy part of a chain, the development of theory and practice in the field of architecture will have far-reaching significance. There is a neglect of traditional building technology issues in the protection of architectural heritage, traditional construction technology plays an important role in the building heritage protection system. Our architectural heritage protection from the perspective of the role of traditional Chinese architecture technology and explore effective ways to protect and respect their heritage.展开更多
The aim of this research was to find out whether the effect of chemical corrosion changes mechanical characteristics of surface layers of wooden construction elements. Degradation of the surface layers of wood was cau...The aim of this research was to find out whether the effect of chemical corrosion changes mechanical characteristics of surface layers of wooden construction elements. Degradation of the surface layers of wood was caused by chemical reactions of the basic substances of wood mass with compounds contained in antifire coatings. Fire retardants containing corrosive substances were often and repeatedly used in the Czech Republic on many wooden building constructions. This process of chemical corrosion is in practise called as ＂surface defibering of wood＂. This contribution presents standard and special experimental methods used for measuring the selected mechanical characteristics （compression strength, tension strength, bending strength, hardness and impact resistance） in the damaged surface layer of wooden construction elements. The material for experimental measuring was a construction element removed from a historical roof （ca 150 years old）. Mechanical characteristics of the surface layer of the defibered element were compared with the values measured in the deeper subsurface layer of non-damaged wood. The results of the experiments proved loss of cohesive strength and decrease of mechanical characteristics of wood only in a thin surface layer.展开更多
基金the support by the National Key Research and Development Program of China(No.2016YFC0400408)
文摘Crystals of a new organometallic nonlinear optical （NLO） compound, di-ta-chloro-bis[chlorotri（thiourea）bismuth（Ⅲ）]- pentachloro（thiourea）bismuth-ate（Ⅲ） （DCBPB）, have been successfully grown from formic acid aqueous solutions of thio-urea and bismuth chloride by a slow evaporation technique. The crystal structure and atomic composition of DCBPB have been confirmed by single crystal X-ray diffraction （SCXRD）, Fourier transform infrared spectra, and elemental analysis. The SCXRD results proved that DCBPB crystallizes in triclinic space group P1 with unit cell dimensions of a = 7.0606（2） A, b = 8.8106（4） A, c = 16.3247（8） A, a = 99.242（4）°, fl = 95.309（3）°, ）/= 105.856（3）°, and Z= 2. DCBPB crystal exhibits excel-lent transmittance from 500 to 2500 nm and green fluorescence with maximum emission at 508 nm. The thermogravimetric-differential scanning calorimetry （TG-DSC） analysis indicates that a solid-phase reaction took place at 170.1 ℃, whereas the decomposition temperature of the crystal material was 189℃. The NLO property obtained by the Kurtz powder test showed that the second harmonic generation efficiency of DCBPB crystal is two-seventh of KDP crystal.
文摘In this context, traditional building crafts craftsman in artistic conception is under the control, use the appropriate tools or equipment, according to the ages, follow the way from raw material acquisition, manufacture components to install molding, to complete a post-renovation process technology ; endangered intangible cultural heritage in urgent need of rescue and system protection. In this paper, the current status of our architectural heritage protection process, analyzes the signi？ cance of the protection framework and ideas, discuss their research methods to analyze the feasibility of building process aimed at promoting heritage protection process, to resolve the current architectural Heritage Protection the “lost technology” and “craftsman team fault,” the urgent problem for protection policies provide reference formulation. On the building process is about building sophisticated cognitive system theory and principles and methods of generation, including the principle of building technology, building technology system structure, and evolution of construction technology paradigm, Chinese modern architecture and sophisticated analysis of the problem 4 to improve its strategy part of a chain, the development of theory and practice in the field of architecture will have far-reaching significance. There is a neglect of traditional building technology issues in the protection of architectural heritage, traditional construction technology plays an important role in the building heritage protection system. Our architectural heritage protection from the perspective of the role of traditional Chinese architecture technology and explore effective ways to protect and respect their heritage.
文摘The aim of this research was to find out whether the effect of chemical corrosion changes mechanical characteristics of surface layers of wooden construction elements. Degradation of the surface layers of wood was caused by chemical reactions of the basic substances of wood mass with compounds contained in antifire coatings. Fire retardants containing corrosive substances were often and repeatedly used in the Czech Republic on many wooden building constructions. This process of chemical corrosion is in practise called as ＂surface defibering of wood＂. This contribution presents standard and special experimental methods used for measuring the selected mechanical characteristics （compression strength, tension strength, bending strength, hardness and impact resistance） in the damaged surface layer of wooden construction elements. The material for experimental measuring was a construction element removed from a historical roof （ca 150 years old）. Mechanical characteristics of the surface layer of the defibered element were compared with the values measured in the deeper subsurface layer of non-damaged wood. The results of the experiments proved loss of cohesive strength and decrease of mechanical characteristics of wood only in a thin surface layer.
