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Research on a New Process of Preparation for Nano-SiO_2 with High Activity and Mesopores

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Journal of Materials Science & Technology 2004年第3期20卷 353-356页

作者： Ruijing ZHANG Ke YANG Tianyng XIONG institute of Metal Resarch,chinese academy of{3.,Shenyang 110016, China Inst. of Metal Res. Chinese Acad. of Sci. Shenyang 110016 China

Nano-SiO_2 with high activity and mesopores was prepared through sol-gel synthesis followed by low-temperatureheat treatment and ball milling firstly in our experiments. TEM was performed to measure particle sizes. Nitrogenadsorption experiments were carried out to estimate specific surface area, porous distribution and porous ratio by BETand BJH methods. The content of Si-OH in SiO_2 surface was calculated by analysis of the results of hydrogen-oxygencontent mensuration (HOCM). As a result, appropriate heat treatment system and ball milling time are important topreparation for nano-SiO_2 with high activity and mesopores, which are 5.5. nm particles, 5.6 nm average aperture,85.～93. porous ratio, and 5.%～5.% Si-OH content in surface. Nano-SiO_2 with that structure has high surfaceenergy and activity. This process, which has simple facilities and operation rules, is a new way of preparation fornano-SiO_2 with high activity and mesopores.

关键词： Heat treatment Ball milling Mesopores Nano-SiO_2

SOLVING INTEGRAL EQUATIONS WITH LOGARITHMICKERNEL BY USING PERIODIC QUASI-WAVELETSOLVING INTEGRAL EQUATIONS WITH LOGARITHMICKERNEL BY USING PERIODIC QUASI-WAVELET

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Journal of Computational Mathematics 2000年第5期18卷 487-512页

作者： Han-lin Chen,Si-long Peng (institute of Mathematics, chinese academy of sciences, Beijing 100080, China) 中科院数学所北京 100080

In solving integral equations with logarithmic kernel which arises from the boundary integral equation reformulation of some boundary value problems for the two dimensional Helmholtz equation, we combine the Galerkin method with Beylkin's ([2]) approach, series of dense and nonsymmetric matrices may appear if we use traditional method. By appealing the so-called periodic quasi-wavelet (PQW in abbr.) ([5.), some of theme matrices become diagonal, therefore we can the a algorithm with only O(K(m)2) arithmetic operations where m is the highest level. The Galerkin approximation has a polynomial rate of convergence.

关键词： Periodic Quasi-Wavelet Integral equation Multiscale.

Oxygen Permeation Behaviors and Hardening Effect of Titanium Alloys at High Temperature

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Journal of Materials Science & Technology 2004年第6期20卷 719-723页

作者： Hongyan MA, Maocai WANG and Weitao WUState Key Laboratory for Corrosion and Protection, institute of Metai Research, chinese academy of sciences, Shenyang 110016, ChinaGraduate School of the chinese academy of sciences, Beijing 10003., China Lab. for Corrosion and Protection Inst. of Metal Res. Chinese Acad. of Sci. Shenyang 110016 China Graduate Sch. Chinese Acad. of Sci. Beijing 100039 China

In order to improve the surface hardness and wear resistance of Ti and Ti alloy components, an oxygen permeation treatment (OPT) was developed. The oxygen permeation behaviors of three Ti alloys, TA2, TB5.and TC11, treated in air with O-P medium at high temperature have been studied. The results show that the 0-P treatment can significantly improve the surface hardness of Ti alloys. The oxidation mass-gain of β-Ti alloy (TB5. is much higher than α-Ti alloy (TA2) under the same condition, while α+β Ti alloy (TC11) is the lowest. All the Ti alloys treated at this condition produce two surface layers: the outer layer consists mainly of TiO2, as well as trace of other oxides, and the inner layer consists of a Ti-O interstitial solid solution formed by the diffusion of oxygen in α crystal lattice. Thick scales of β Ti alloy (TB5. are easily formed depending mainly on the poor solid solution content of oxygen, while deep solution layer can be formed since partial β phase has been transformed into α phase. The scales of α-β Ti alloy (TC11) are very thin and compact. Aluminum-rich zone, as well as deficient zone, is found in oxide layers. A crystallographic characterization of oxygen solution layer has been performed and evaluated by crystallographic lattice constant.

关键词： Microstructure Oxygen permeation Titanium Solid solution

Optical Recording Performance of Azo Nickel Chelate Thin Film

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chinese Journal of Lasers 1999年第5期8卷 444-448页

作者： YIN Jinlong WANG Shuangqing GAN Fuxi(Shanghai institute of Optics and Fine Mechanics, The chinese academy of sciences,Shanghai 201800, Chinainstitute of Photographic Chemistry, The chinese academy of sciences,Beijing 100101, China) 中科院上海光学精密机械所上海 201800 中科院感光化学所北京 100101 中科院上海光学精密机械所上海

The absorption, transmission and reflection spectra of spin-coated films of Ni(azo)2(azo nickel chelate) were measured. Because of the intermolecular aggregation, the absorption peak of Ni(azo)2 thin film has a red-shift of about 4o nm with respect to that of it in methanol solution. The fabricated optica disk showed a reflectivity of 48% and its carrier-noise ratio (CNR) was greater than 45.dB when recording with 7. 5.mW laser power at the wavelength of 780nm.

关键词： azo dye optical recording absorption spectra

Secondary Metabolites of Aspergillus niger CIBAS No. 17

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Secondary Metabolites of Aspergillus niger CIBAS No. 17

Measurement of ^(15.)Sm-EDTMP bone uptake bywhole-body scintigraphy and its application toindividualized treatment dosimetry of bone metastasis

中国化学会第四届有机化学学术会议

作者： Guo-You Li, Bo-Gang Li, Tao Yang, Guang-Ye Liu, Guo-Lin Zhang chengdu institute of biology,{3., chengdu 610041

＜正＞One new compound, 3.pentadecanyl-phenol （1）, together with three known compounds, 4,4-dimethyl-5.α -ergosta-8, 24（28）-dien-3.β-ol （2）, （20S,22E,24R）-ergosta-5.7,22-trien-3.β -ol （3., 5.a ,8 a -epidioxy（20S,22E,24R）-ergosta-6,22-dien-3.β -ol （4）（Figure 1）, were isolated from the methanol extract of mycelium of Aspergillus niger CIBAS No. 17. Their structures were elucidated based on spectroscopic analysis.

关键词： Aspergillus niger Mycelium Fermentation Metabolites Ergosterol

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Nuclear Science and Techniques 2000年第4期11卷 257-262页

作者： LI Lin, DENG Hou-Fu, LIANG Zheng-Lu, LI Yun-Chun, KUANG An-Ren, TAN Tian-Zhi (The First Affiliated Hospital, West China University of Medical sciences, chengdu 610041) LUO Shun-Zhong (Southwest institute of Nuclear Physics and Chemistry,{3. 610003. 华西医科大学四川成都 610041 中国工程物理研究院西南核物理与化学所四川成都 610003

To calculate a safe and effective 15.Sm-EDTMP therapy dose, a whole-body scintigraphy technique for prospective individual dosimetry was developed and the results were compared with 5. urine collection method in 20 patients with bone metastases. Anterior and posterior whole-body images were obtained 10 min and 5.h after intravenous injection of 740 MBq 15.Sm-EDTMP and the bone uptake value was determined. There is a close correlation between the bone uptake value obtained from the whole-body scintigraphy and 5.h urine collection method (r=0.93.. The radiation absorption dose to red marrow was limited to 1.4 Gy and the administered activity calculated from bone uptake value by whole-body scintigraphy was 1.40-2.27GBq (mean 1.90 GBq). If the activity was calculated according to the standard body weight of 3. ***-1, the administered activity would be 1.75.2.41 GBq (mean 2.18), the radiation absorption dose to red marrow would be 1.3.-2.27 Gy (mean 1.63.Gy), but at these doses significant myelotoxicity would be anticipated, thus emphasizing the need for individual prospective dosimetry.

关键词： ^15.Sm-EDTMP 放射剂量钐15. 全身闪烁扫描法放射性核素标记骨移位诊断

A RIFTING STORY OF SOUTH CHINA, WITH PARTICULAR REFERENCE TO RODINIA BREAKUP

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地学前缘 2000年第S1期7卷 313-315页

作者： Wang Jian 1, Pan Guitang\+1, Li Zhengxiang\+2, Li Xianhua\+3.[WT5.5.BX](1.chengdu {3. of Geology and Mineral Resources, chinese {3. of Geological sciences, chengdu 610082, China 2.Tectonic Special Research Center, Department of Geolog

An integrated sedimentological, sequence stratigraphic, tectonic\|stratigraphic, isotope chronostratigraphic and isotope (element) geochemical analysis indicates that the Neoproterozoic basins in South China are characteristic of rift basins, and their formation and evolution are closely related to the breakup of the supercontinent Rodinia. (1) Neoproterozoic basins in South China can be divided into three major provinces: the southeastern Yangtze province, the Kangdian province along the western margin of the Yangtze block, and the Cathaysia province. They can be further subdivided into five subprovinces and eleven microprovinces on the basis of tectonic settings, sedimentary facies and palaeogeography,and outcrop sequence stratigraphy.(2) Four genetic facies associations and two environmental facies associations can be recognized in the Neoproterozoic basins. The former include① continental volcanic eruptive genetic facies association; ② submarine volcanic eruptive genetic facies association; ③ tillite genetic facies association; and ④ eustatic event deposits genetic facies association. The latter comprise: ① continental environmental facies association, and ② marine environmental facies association.

关键词： rodinia supercontinent Neoproterozoic rifting South China SHR IMP

Mineralization episode of porphyry copper deposits in the Jinshajiang-Red River mineralization belt: Re-Os dating

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Science China Earth sciences 2005年第2期48卷 192-198页

作者： WANG Denghong, QU Wenjun, LI Zhiwei, YIN Hanlong4 & CHEN Yuchuan institute of Mineral Resources, chinese academy of Geological{3., Beijing 10003., China National Center of Rock and Mineral Analysis, chinese academy of Geological{3., Beijing 10003., China Resource Assessment Center of Yunnan, Kunming 65.011, China institute of Geology and Geophysics, chinese academy of sciences, Beijing 100101, China chinese academy of Geological{3., Beijing 10003., China 1. institute of Mineral Resources Chinese Academy of Geological Sciences 100037 Beijing China 2. National Center of Rock and Mineral Analysis Chinese Academy of Geological Sciences 100037 Beijing China 3. Resource Assessment Center of Yunnan 650011 Kunming China 4. institute of Geology and Geophysics Chinese Academy of Sciences 100101 Beijing China 5. chinese academy of Geological {3. 100037 Beijing China

Re-Os isotopic dating for the molybdenites from the porphyry copper deposits of the Jinshajiang-Red River mineralization belt in Yunnan Province yields isochron ages of 3..9±1.1 Ma for the Machangqing deposit and 3..4±0.5.Ma for the Tongchang deposit. This result shows that both the Machangqing and the Tongchang porphyry Cu-Mo deposits from two different ore-fields formed simultaneously. This new data and the published Re-Os model ages of molybdenite (3.0}4 Ma, 3.0}9 Ma, 3..2 Ma) of the Yulong porphyry copper deposit in Tibet, which is located in the same Jinshajiang-Red River mineralization belt as the Machangqing deposit and the Tongchang deposit, suggest that these three Cenozoic porphyry copper deposits in the Jinshajiang-Red River mineralization belt were contemporary for their mineralization episode. That is to say, even their present locality is far away and nearly iso-distantly distributed, these three porphyry Cu(Mo) deposits belong to the same mineralization episode at the end of Eocene.

关键词： Re-Os isotopic dating, porphyry Cu deposits, Cenozoic, mineralization episode.

Identification of a NF-кB site in the negative regulatory element (ε-NRAII) of human ε-globin gene and its binding protein NF-кB p5. in the nuclei of K5.2 cells

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Cell Research 2002年第1期12卷 79-82页

作者： CHUN Hui HOU, JIAN HUANG, Ruo LAN QIAN Group of Globin Gene Expression and Regulation, State Key Labortory of Molecular biology, institute of Biochemistry and Cell biology, Shanghai institutes for Biological sciences,{5., Shanghai Group of Globin Gene Expression and Regulation Institute of Biochemistry and Cell Biology Shanghai Institutes for Biological Sciences Chinese Academy of Sciences State Key Labortory of Molecular Biology 上海 200031 Group of Globin Gene Expression and Regulation Institute of Biochemistry and Cell Biology Shanghai Institutes for Biological Sciences Chinese Academy of Sciences State Key Labortory of Molecular Biology 上海 200031

The developmental control of the human e-globin gene expression is mediated by transcription regulatory elements in the 5. flanking DNA of this gene. Sequence analysis has revealed a DNA motif (GGGGAATTTGCT) similar to NF-кB consensus sequence resides in the negative regulatory element (-3.28bp～ -2902bp, termed ε-NRAII) 5. to the cap site of this gene. NRF DNA fragment (-3.10bp～ -2986bp) containing the NF-кB motif similar sequence was synthesized and used in electrophoresis mobility shift assay (EMSA) and competitive analysis. Data showed that a protein factor from nuclear extracts of K5.2 cells specifically interacted with NRF DNA fragment. The synthetic NF DNA fragment (containing NF-кB consensus sequence) could competed for the protein binding, but MNF DNA fragment (mutated NF-кB motif) could not, suggesting that the binding protein is a member of NF-кB/Rel family. Western blot assay demonstrated that the molecular weight of NF-кB protein in the nuclei of K5.2 cells is 5.ku. We suggested that NF-кB p5. may play an important role in the regulation of human c-globin gene expression.

关键词： Human ε-globin gene negative regulatory element NE-кB p5..