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金融多措并举支持经济高质量发展

中国金融 2024年第19期 9-15页

作者：本刊编辑部不详

2024年9月24日,国务院新闻办公室举行新闻发布会,中国人民银行行长潘功胜、国家金融监督管理总局局长李云泽、中国证券监督管理委员会主席吴清出席发布会并介绍金融支持经济高质量发展有关情况。“新政频出”成为此次发布会的亮点,这让... 详细信息

2024年9月24日,国务院新闻办公室举行新闻发布会,中国人民银行行长潘功胜、国家金融监督管理总局局长李云泽、中国证券监督管理委员会主席吴清出席发布会并介绍金融支持经济高质量发展有关情况。“新政频出”成为此次发布会的亮点,这让公众感受到了金融支持经济高质量发展的力度,支持实体经济发展的深度和提升老百姓生活幸福感、满足感的温度。

关键词：金融监督管理金融支持经济实体经济发展中国证券监督管理委员会高质量发展多措并举生活幸福感新闻发布会

Superconductivity of small metal grains

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Science china(Physics,Mechanics & Astronomy) 2005年第4期48卷 431-441页

作者： ZHENG Renrong1 CHEN Zhiqian2 & ZHU Shunquan1,3.1. department of Physics, Shanghai Normal university, Shanghai 20023., china 2. department of Physics, Southwest Normal university, Chongqing 400715, china 3. department of Computer and Electric Technology, Shanghai Business School, Shanghai 201400, china 1. department of Physics Shanghai Normal University 200234 Shanghai China 2. department of Physics Southwest Normal University 400715 Chongqing China 3. department of Computer and Electric Technology Shanghai Business School 201400 Shanghai China

The formulas of the energy gap and superconducting critical temperature appropriate for systems with both odd and even number of electrons are derived; the bases of the derivations are BCS theory and energy level statistics. Numerical results qualitatively agree with the experimental phenomena. i.e., the superconductivity of small metallic grains will first enhance then decrease to zero when the grain are getting smaller and smaller. The calculations indicate that the above phenomena happen in the metallic grains belonging to Gaussian Orthogonal Ensemble (GOE) and Gaussian Unitary ensemble (GUE) with zero spin; The superconductivity of small metallic grains in Gaussian Symplectic Ensemble (GSE) will monotonically decrease to zero with the decreasing of the grain size. The analyses suggest that the superconductivity enhancements come from pairing and the balance of the strengths between spin-orbital coupling and external magnetic field. In order to take the latter into account, it is necessary to include the level statistics given by Random Matrix Theory (RMT) in describing small metallic grains.

关键词： size effect, superconductivity enhancements, small metallic grains.

Morphology and electrical conductivity of PACS

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Journal of Environmental Sciences 2000年第3期12卷 319-324页

作者： GAO Bao\|yu\+1, LIU Zong\|gang\+2, YUE Qin\|yan\+3. ZHAO Hua\|zhang\+3.(1. department of Environmental Engineering, Shandong university, Jinan 250100, china 2. Environmental Monitoring Station of Huaiyin, Jinan 250022, china 3. department of Environ 山东大学山东济南 2 50 1 0 0 山东济南市槐荫区环境监测山东济南 2 50 0 2 2

Polyaluminium chlorides with sulfate ion(PACS) were prepared by using AlCl 3.6H 2O, Al(SO 4) 3.18H 2O and Na 2CO 3.as raw materials. The effects of basicity ( r ), Al 3. /SO 4 2- molar ratio and aging time on the morphology of PACS were observed by transmission electrical microscope. The influence of aging time on charge neutralization and coagulation effect of PACS was studied. The effects of basicity ( r ), Al 3. /SO 4 2- molar ratio and aging time on the electrical conductivity of PACS solution were also investigated. The experimental results show that the degree of polymerization of polyaluminium chloride(PAC) increases when SO 4 2- ion is added. The higher the basicity( r ) and the longer the aging time, the larger the size of polymer PACS. The ability of PACS neutralizing the charge on Kaolinite decreases with the increase of aging time. The electrical conductivity of PACS solution(the concentration of Al 3. ion is 0.18 mol/L) with different aging time is the function of the basicity and Al 3. /SO 4 2- molar ratios and has its maximum at r =0.5 and Al 3. /SO 4 2- =12.

关键词： coagulant PACS morphology transmission electron microscope electrical conductivity coagulation

THE (ｕ＋κ)-ORBIT OF ESSENTIALLY NORMAL OPERATORS AND COMPACT PERTURBATIONS OF STRONGLY IRREDUCIBLE OPERATORS

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Chinese Annals of Mathematics,Series B 2000年第2期21卷 237-248页

作者： JIYOUQING JIANGCHUNLAN WANGZONGYAO departmentofMathematics JilinUniversityChangchun130023China. departmentofMathematics JilinUniversityChangchun130023China. departmentofMathematics EastChinaUniversityofScienceandTechnologyShanghai200237＂China.

Let н be a complex, separable, infinite dimensional Hilbert space, T　ε（Ｈ）. （ｕ＋Ｋ）（T） denotes the （ｕ＋ｋ）-orbit of T, i.e., （ｕ＋ｋ）（T） = {R-1TR: R is invertible and of the form unitary plus compact}. Let be an analytic and simply connected Cauchy domain in C and n ε N. A（, n） denotes the class of operators, each of which satisfies （i） T is essentially normal; （ii） σ（T） =,　ρF（T）　∩ σ（T） = ; （iii） ind （λ-T） = -n, nul （λ-T） = 0 （λ∈Ω ）. It is proved that given T1, T2 ε A（, n） and ε > 0, there exists a compact operator K with K <ε such that T1 +Kε （ｕ＋ｋ）（T2）. This result generalizes a result of P. S. Guinand and L. Marcoux [6,15]. Furthermore, the authors give a character of the norm closure of （ｕ＋Ｋ）（T）, and prove that for each T ε A（, n）, there exists a compact （SI） perturbation of T whose norm can be arbitrarily small.

关键词： Essentially normal (u+k)-orbit Compact perturbation Spectrum Strongly irreducible operator

ELECTROCHEMICAL SYNTHESIS AND PROPERTIES OF POLY(AZURE B)

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Chinese Journal of Polymer Science 2001年第4期19卷 359-370页

作者： Dan Shan Shao-lin Mu department of chemistry School of Sciences, Yangzhou university Yangzhou 225002, {3. Yangzhou Univ Sch Sci Dept Chem Yangzhou 225002 Peoples R China

A blue poly(azure B) film has been synthesized using repeated potential cycling between -0.25 and 1.10 V (versus SCE). The electrolytic solution consisted of 2.5 mmol dm(-3. azure B, 0.5 mol dm(-3. NaCl and 0.2 mol dm(-3. NaH2PO4 at the pH range of 2.0 to 11.0. The in situ visible spectrum during electrolysis of azure B shows that the intensity at 740 nm peak increases with increasing numbers of potential cycles, which is attributable to the formation of poly(azure B). The wavelength of its corresponding absorption peak is 98 nm longer than that of azure B. The polymerization rate is strongly affected by pH values. The anodic peak potential and cathodic peak potential of the poly(azure B) in a solution of pH 3.0 are not affected by increasing the scan rate from 25 to 600 mV s(-1). Poly(azure B) has good electrochemical reversibility and fast charge transfer characteristic in the pH range of 2.0 and 11.0. The conductivity of poly(azure B) is 1.5 x 10(-4) S cm(-1) According to the differences between FTIR spectra of poly(azure B) and azure B, an electrochemical polymerization mechanism of azure B is proposed in this paper.

关键词： azure B electrochemical polymerization electrochemical properties conductivity in situ UV-visible spectra FTIR spectra

Preparation and Conductivity of Triheteropoly Tungstozincoaluminic Acid

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Rare Metals 2001年第4期20卷 221-223页

作者： Qingyin Wu department of chemistry, Zhejiang university, Hangzhou 3.0027, {3. Zhejiang Univ Dept Chem Hangzhou 310027 Peoples R China

The ternary undecatungstozincoaluminic heteropoly acid H-7[Al(H2O)ZnW11O3.](.)12H(2)O was prepared by the ion exchanging-cooling method. The optimal proportion of solutions of the component elements and the pH of the synthesis reaction were given. The product was characterized by chemical analysis, potentiometric titration, IR, UV, XRD and TG-DTA. AC impedance measurement results show that its proton conductivity is 1.3.x10(-4) S/cm at 18 degreesC.

关键词： heteropoly acid tungstozincoaluminic acid protonic conductivity

Petrogenesis of Songshugou dunite body in the Qinling orogenic belt, Central china: Constraints from geochemistry and melt inclusions

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Science china Earth Sciences 2005年第8期48卷 1146-1157页

作者： SU Li1,2, SONG Shuguang3.& ZHOU Dingwu1 1. Key Laboratory of Continental Dynamics of the Ministry of Education, department of Geology, Northwestern university, Xi’an 710069, china 2. The Geological Lab Center, china university of Geosciences (Beijing), Beijing 100083. china 3. Key Laboratory of Orogenic Belts of the Ministry of Education, department of Geology, Peking university, Beijing 100871, china 1. Key Laboratory of Continental Dynamics of the Ministry of Education Department of Geology Northwestern University 710069 Xi’an China 2. The Geological Lab Center China University of Geosciences 100083 (Beijing)Beijing China 3. Key Laboratory of Orogenic Belts of the Ministry of Education Department of Geology Peking University 100871 Beijing China

The Songshugou dunite body, which occupies an area of about 20 km2, is the largest ultramafic massif in the eastern Qinling orogenic belt, Central china. The major compo-nent of this body is dunitic rocks including mylonitic dunite and coarse-grained dunite; they oc-cupy about 95 vol% of the total body. Petrography, mineral composition, major and trace ele-ments and primitive melt inclusions have been investigated in this paper; all revealed that this dunite body is the product of melt-rock interaction by porous percolation flow. In comparison with dunite sills or veins in harzburgite from the basal part of Oman ophiolite, this dunite body is characterized by lower contents of Al2O3. CaO and HREE but higher content of highly incom-patible elements and Zr and Hf. The LREE enriched patterns and primitive mantle normalized spidergrams of trace elements are also different from the Oman dunite. Combining with melt in-clusions observed in olivines, we conclude that this dunite body is the product of large- scale porous percolation flow of high-MgO melts within depleted mantle peridotites. The high-MgO magma, in essence, was most probably produced at the hot head of an upwelling mantle plume. The occurrence of the Songshugou dunite body is closely associated with the activity of mantle super-plume in Neo-Proterozoic era in the Yangtze Craton.

关键词： Songshugou dunite body, geochemistry, melt inclusion, mantle plume, Qinling orogenic belt.

Synthesis and Crystal Structure of Rctt-1-(2-benzoxazolyl)-2-(4-chlorophenyl)-4-phenyl-3.(4-pyridinyl)cyclobutane

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Chinese Journal of Structural chemistry 2003年第1期22卷 65-69页

作者： ZHUANG Jun-Peng ZHANG Wen-Qin② (department of chemistry, Tianjin university, Tianjin 3.0072, {3.) Tianjin Univ Dept Chem Tianjin 300072 Peoples R China

The title compound (C28H21ClN2O, Mr = 43..92) was synthesized by the cross- photodimerization of (E)-2-(2-phenylethenyl)benzoxazole and (E)-4-[2-(4-chlorophenyl)ethenyl]- pyridine in sulfuric acid solution. Its molecular structure has been unequivocally determined by X-ray crystallography. The title compound belongs to triclinic system, space group P?with cell parameters: a = 9.648(3., b = 10.458(4), c = 12.106(4) , a = 89.089(7), b = 75.644(6), g = 68.441(7)? V = 1096.7(7) 3. Z = 2, Dc = 1.3.3.g/cm3. F(000) = 456 and m(MoKa) = 0.198 mm-1. The final R and wR are 0.0627 and 0.1285, respectively for 173. observed reflections with I > 2s(I). S = 0.921 and (/s)max = 0.001. The cyclobutane ring has a puckered conformation with four different aryl groups substituted on each carbon atom. The dihedral angles of the cyclobutane ring are 20.2 and 20.6? The bond distances of the cyclobutane ring are 1.541, 1.555, 1.560 and 1.563.? respectively, which are slightly longer than that of the normal CC single bond. The title compound is the only cross-dimer and its two heteroaryl groups are situated at the trans-1,3.position of the cyclobutane ring, revealing that the cross-photodimerization proceeds in a head-to-tail pattern with high stereo-selectivity.

关键词： cyclobutane photodimerization crystal structure

Measurement of the linear electro-optic coefficient of a minute cBN sample

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Science china(Technological Sciences) 2005年第2期48卷 233-340页

作者： DOU Qingping1, , MA Haitao1, JIA Gang1, CHEN Zhanguo1 2 & ZHANG Tiechen3.1. College of Electronic Science and Engineering, State Key Laboratory on Integrated Optoelectronics, jilin university, Changchun 13.023. china 2. Mudanjiang Normal Institute, Mudanjiang 157012, china 3. State Key Laboratory of Superhard Materials, jilin university, Changchun 13.012, china 1. College of Electronic Science and Engineering State Key Laboratory on Integrated Optoelectronics Jilin University 130023 Changchun China 2. Mudanjiang Normal Institute 157012 Mudanjiang China 3. State Key Laboratory of Superhard Materials Jilin University 130012 Changchun China

Cubic boron nitride (cBN) is a kind of artificial (synthetic) crystal. Transverse electro-optic modulation in a minute cBN sample was carried out. Basing on the practical form of the crystal, we established the theoretical and experimental method according to the sample. For the first time, the linear electro-optic effect was observed in cBN, and half-wave voltage of the cBN sample was measured successfully. Furthermore, its linear electro-optic coefficient was calculated at 1.17×10?14 m/V.

关键词： cBN crystal, linear electro-optic effect, half-wave voltage, linear electro-optic coefficient.