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Ligand-dependent aggregation-enhanced photoacoustic of atomically precise metal nanocluster

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Aggregate 2024年第1期5卷 196-203页

作者： Changlin Zhou Meng Wang Qiaofeng Yao Yu Zhou Chuantao Hou Jianfei Xia Zonghua Wang Jishi Chen Jianping Xie College of Chemistry and Chemical Engineering Shandong Sino-Japanese Center for Collaborative Research of Carbon NanomaterialsInstrumental Analysis Center of Qingdao UniversityQingdao UniversityQingdaoP.R.China Tianjin Key Laboratory of Molecular Optoelectr.nic Sciences Department of ChemistrySchool of ScienceTianjin UniversityTianjinP.R.China Qingdao Boting Hydrogen Age Ocean Technol R&D ctr. Qingdao Boting Technol Co.Ltd.Shandong Hydrogen Times Marine Technology Co.Ltd.QingdaoP.R.China Department of Chemical and Biomolecular Engineering National University of SingaporeSingapore Joint School of National University of Singapore and Tianjin University International Campus of Tianjin UniversityBinhai New CityFuzhouP.R.China

Atomically precise metal nanoclusters(MNCs),as a potential type of photoacoustic(PA)contrast agent,are limited in application due to their low PA conversion efficiency(PACE).Here,with hydrophilic Au25SR18(SR=thiolate)as model NCs,we present a result that weakly polar solvent induces aggregation,which effectively enhances PA intensity and *** PA intensity and PACE are highly dependent on the degree of aggregation,while the aggregation-enhanced PA intensity(AEPA)positively correlates to the protected *** an AEPA phenomenon indicates that aggregation actually accelerates the intramolecular motion of Au NCs,and enlarges the proportion of excited state energy dissipated through vibrational *** result conflicts with the restriction of intramolecular motion mechanism of aggregation-induced *** experiments show that the increased energy of AEPA originates from the aggregation inhibiting the intermolecular energy transfer from excited Au NCs to their surrounding medium molecules,including solvent molecule and dissolved oxygen,rather than restricting radiative *** study develops a new strategy for enhancing the PA intensity of Au NCs,and contributes to a deeper understanding of the origin of the PA signal and the excited state energy dissipation processes for MNCs.

关键词： aggregation-enhanced photoacoustic gold nanocluster intermolecular excited state energy transfer intramolecular motion ligand effect

Preparation and Characterization of TiO_2/TiN/TiO_2 Multi-layer Solar Control Coatings Deposited by D.C. Reactive Magnetron Sputtering at Different Substrate Temperature

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Journal of Wuhan University of Technology(Materials Science) 2001年第2期16卷 9-12页

作者：赵青南 ctr. for Materials Res. and analysis Wuhan University of Technology Wuhan 430070 China

Transparent TiO2/TiN/TiO2 multi-layer solar control coatings were prepared on normal soda-lime-silica float glass substrate by using d.c. reactive magnetron sputtering at substrate temperature ranging from room temperature to 620℃ . The dependence of optical properties of the coatings and the coating composition, on the substrate temperature was studied. The results of the optical properties show that as the substrate temperature increases, a visible transmittance as high as 65% can be obtained. When the substrate temperature is higher than 370℃ , the infrared reflectance decreases. The results of X-ray photoelectr.n spectr.scopy (XPS) show that when the substrate temperature is higher than 520℃ in oxygen atmosphere, the formation of thin surface over-layers (TiNxOy,) on top of the TiN films can be observed. When the substrate temperature is at 62℃ , the oxynitride become TiO2, which results in the optical degradation of TiN layer in infrared reflectance.

关键词： solar control coatings sputtering substrate temperature optical properties XPS TiNx0y

MULTI-PEAK MATCH INTENSITY RATIO METHOD OF QUANTI-TATIVE X-RAY DIFFRACTION PHASE analysis

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Acta Metallurgica Sinica(English Letters) 2003年第6期16卷 489-494页

作者： G. Chu, Y.F. Cong and H.J. YouResearch Center of analysis and Test, Liaoning University of Petroleum & Chemical Technology, Fushun 113001, China Res. ctr. of analysis and Test Liaoning Univ. of Petrochem. Tehnol. Fushun 113001 China

A new method for quantitative phase analysis is proposed by using X-ray diffraction multi-peak match intensity ratio. This method can obtain the multi-peak match intensity ratio among each phase in the mixture sample by using all diffraction peak data in the mixture sample X-ray diffraction spectr.m and combining the relative intensity distribution data of each phase standard peak in JCPDS card to carry on the least square method regression analysis. It is benefit to improve the precision of quantitative phase analysis that the given single line ratio which is usually adopted is taken the place of the multi-peak match intensity ratio and is used in X-ray diffraction quantitative phase analysis of the mixture sample. By analyzing four-group mixture sample, adopting multi-peak match intensity ratio and X-ray diffraction quantitative phase analysis principle of combining the adiabatic and matrix flushing method, it is tested that the experimental results are identical with theory.

关键词： X-ray diffraction multi-peak match intensity ratio quantitative phase analysis

STUDY OF AIRFLOW HOMOGENEITY STANDARD IN REGENERATIVE CHAMBER OF TANK FURNACE

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Journal of Wuhan University of Technology(Materials Science) 1997年第3期12卷 56-62页

作者：王玉成 Wuhan University of Technology China ctr. for Materials Res. and analysis Wuhan Univ. of Tech. Wuhan 430070 China

The authers compared six used criterions of influencing homogeneity of moving airflow in virtue of errors such as variance Q, average square deviation T, homogeneous indices H, inhomogeneous degree W, range R and nonuniform index S. The auther think that the effects of the errors will be magnified when all these old stnadards were calculated, especially for higher airflow homogeneity, thus the reliability of these norms would De reduced. The authers put forward two new standards to lower influence of error.

关键词： regenerative chamber airflow homogeneity standard tank furnace

Effects of Cure Pressure Induced Voids on the Mechanical Strength of Carbon/Epoxy Laminates

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Journal of Materials Science & Technology 2005年第1期21卷 87-91页

作者： Ling LIU, Boming ZHANG, Zhanjun WU and Dianfu WANGCenter for Composite Materials, Harbin Institute of Technology, Harbin 150001, ChinaProf., ctr. for Composite Mat. Harbin Inst. of Technol. Harbin 150001 China

This work aims at designing a set of curing pressure routes to produce laminates with various void contents. The effects of various consolidation pressures resulting in different void contents on mechanical strength of carbon/epoxy laminates have been examined. Characterization of the voids, in terms of void volume fraction, void distribution, size, and shape, was performed by standard test, ultrasonic inspection and metallographic analysis. The interlaminar shear strength was meas.red by the short-beam method. An empirical model was used to predict the strength vs porosity. The predicted strengths conform well with the experimental data and voids were found to be uniformly distributed throughout the laminate.

关键词： Carbon/epoxy laminates Autoclave curing Void Mechanical strength

Expert Network for Die Casing Defect analysis

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Journal of Materials Science & Technology 2003年第4期19卷 320-323页

作者： Jiadi WANG, Yongfeng JIANG, Chen LU and Wenjiang DINGNational Engineering Research Center for Light Alloy Net Shaping, Shanghai Jiao Tong University, Shanghai, 200030, China ctr. for Light Alloy Net Shaping Shanghai Jiaotong Univ. Shanghai 200030 China

Due to the competition and high cost associated with die casting defects, it is urgent to adopt a rapid and effective method for defect analysis. In this research, a novel expert network approach was proposed to avoid some disadvantages of rule-based expert system. The main objective of the system is to assist die casting engineer in identifying defect, determining the probable causes of defect and proposing remedies to eliminate the defect. 14 common die casting defects could be identified quickly by expert system on the basis of their characteristics. BP neural network in combination with expert system was applied to map the complex relationship between causes and defects, and further explained the cause determination process. Cause determination gives due consideration to practical process conditions. Finally, corrective meas.res were recommended to eliminate the defect and implemented in the sequence of difficulty.

关键词： Neural network Expert system Die casting Defect analysis Back propagation

Is There any Hexazirconium Cluster in the Compounds [HP(t-Bu)_2Ph_3]_3[Zr_6Cl_(18)H_5] and Zr_6Cl_(14)(PPr_3)_4H_4?

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Chinese Chemical Letters 1997年第9期8卷 829-830页

作者： Wen LI ChunHua HU Pei Ju ZHENG(Research Center of analysis and meas.rement, Fudan University, Shanghai 200433) Res. ctr. of Anal. and meas.rement Fudan University Shanghai 200433 China

The [Zr6(μ2-Cl)12Cl6H4]3- ion with C4v Symmetry in the title compounds has been calculated by DV-Xα program. The calculated results show that ther is almost no available covalence bonding between zirconium atoms and significant Zr 4d AO compositions in the MOs. but there are much stronger Zr-Cl(bridging) bonding. All analysis results suggest that these compounds would be the cluster with Zr6Cl12 cage linked by Zr-Cl bridging bonding plus six Cl teminal ligands rather than the hexazirconium cluster in view of the chemical bonding.

关键词： and Zr6Cl PPr3 Is There any Hexazirconium Cluster in the Compounds t-Bu H5 Zr6Cl HP

Eco－tourism　industry　development──An　alternative　to　sustainable　use　of　landscape　resources

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Journal of Environmental Sciences 1996年第3期8卷 298-307页

作者： Lu Yonglong(Research Center for Eco-Environmental Sciences, ChineseAcademy of Sciences, Beijing 100085, China) Res. ctr. for Eco-Environ. Sciences Chinese Academy of Sciences Beijing 100085 China

Traditional tourism is a source of not only income and recreation but also environmental pollution and landscape resource destruction. How to leave the same or even better landscape resources to future generations is the key to sustainable development of tourism industry. Ecotourism industry could be an approach to sustainable use of landscape *** connotation of eco-tourism industry and its differences from the traditional tourism in resource use were given in this paper. The ecological planning for Kangyuan recreation area is taken as an example to demonstrate how to make an eco-tourism industry development plan from a system’s point of *** terms of the characteristics of the landscape resources, advantageous geographic location and principles for eco-tourism industry development,a suitable structure of the eco-tourism industry was presented. Based on ecological suitability analysis of the landscape resource use-analysis of capacity and constraint of landscape resources, spatial distribution of the industry sectors was *** the development process, both opportunities and risks exist, cost-benefit analysis is thus made, and cost-effective strategies and policies are provided for the eco-tourism industry development.

关键词： eco-tourism resource use sustainability

Environmental awareness and the contemporary society of China——an analysis and an understanding

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Journal of Environmental Sciences 1999年第4期11卷 504-509页

作者： XU Song\|ling (Center for Environment and Development, Chinese Academy of Social Sciences, Beijing 100732,China) ctr. for Environment and Development Chinese Academy of Social Sciences Beijing 100732 China

This paper presents an understanding of the relationship between the environmental awareness(EA) and contemporary society of China. The EA of three of the major groups of Chinas society, namely intellectuals, government officials, and urban societies are characterized one by one. A number of factors of affecting the EA were investigated in details, the keys among which are the personal level of knowledge and morality, the social and economic development level, environmental codes, environment\|related professional and public regulations, different professional performances. Some policy proposals are finally provided for enhancing the EA of Chinas society.

关键词： environmental awareness contemporary society of China sustainable development