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Basic functions and unramified local L-factors for split groups

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Science China Mathematics 2017年第5期60卷 777-812页

作者： li wen-wei Academy of Mathematics and Systems Science Chinese Academy of Sciences Beijing 100190 China School of Mathematical Sciences University of Chinese Academy of Sciences Beijing 100049 China

According to a program of Braverman, Kazhdan and NgS, for a large class of split unramified reductive groups G and representations p of the dual group G, the unramified local L-factor L（s, π, ρ） can be expressed as the trace of π（fρ,s） for a function fρ,s with non-compact support whenever Re（s） ≥ 0. Such a function should have useful interpretations in terms of geometry or eombinatories, and it can be plugged into the trace formula to study certain sums of automorphic L-functions. It also fits into the conjectural framework of Schwartz spaces for reductive monoids due to Sakellaridis, who coined the term basic functions; this is supposed to lead to a generalized Tamagawa-Godement-Jaequet theory for （G, ρ）. In this paper, we derive some basic properties for the basic functions fρ,s and interpret them via invariant theory. In particular, their coefficients are interpreted as certain generalized Kostka-Foulkes polynomials defined by Panyushev. These coefficients can be encoded into a rational generating function.

关键词： L-function Satake isomorphism generalized Kostka-Foulkes polynomial

Effects of ultrasonic vibration on plastic deformation of AZ31 during the tensile process

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International Journal of Minerals,Metallurgy and Materials 2011年第1期18卷 70-76页

作者： Tong wen li wei Xia Chen Chun-lei Pei College of Material Science and Engineering Chongqing University Chongqing 400044 China

An investigation on the plastic behavior of AZ31 magnesium alloy under ultrasonic vibration（with a frequency of 15 kHz and a maximum output of 2 kW） during the process of tension at room temperature was conducted to reveal the volume effect of the vibrated plastic deformation of *** characteristics of mechanical properties and microstructures of AZ31 under routine and vibrated tensile processes with different amplitudes were *** is found that ultrasonic vibration has a remarkable influence on the plastic behavior of AZ31 which can be summarized into two opposite aspects：the softening effect which reduces the flow resistance and improves the plasticity,and the hardening effect which decreases the *** a lower amplitude or vibration energy is applied to the tensile sample,the softening effect dominates,leading to a decrease of AZ31 deformation resistance with an increase of *** the application of a high-vibrating amplitude,the hardening effect dominates,resulting in the decline of plasticity and brittle fracture of the samples.

关键词： ultrasonic effects tensile testing magnesium alloys plastic deformation

Surface Modification With Zinc and Zn-Ni Alloy Compositionally Modulated Multilayer Coatings

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Journal of Iron and Steel Research International 2006年第4期13卷 61-67页

作者： FEI Jing-yin liANG Guo-zheng XIN wen-li WANG wei-kang Department of Applied Chemistry Northwestern Polytechnical University Xi＇an 710072 Shaanxi China

Zinc and Zn-Ni alloy compositionally modulated multilayer （CMM） coatings were electrodeposited on to a steel substrate by the successive deposition of zinc and Zn-Ni alloy sublayers from dual baths. The coated samples were evaluated in terms of the surface appearance, surface and cross-sectional morphologies, as well as corrosion resistance. The microstructural characteristics that were examined using the field emission gun scanning electron microscopy （FEGSEM） confirmed the layered structure, grain refinement of the zinc and Zn-Ni alloy CMM coatings, and revealed the existence of microcracks caused by the internal stress in the thick Zn-Ni alloy sublayers. The corrosion resistance that was evaluated by means of the salt spray test shows that the zinc and Zn-Ni alloy CMM coatings were more corrosion-resistant than the monolithic coatings of zinc or Zn-Ni alloy of the same thickness. The possible reasons for the better protective performance of Zn-Ni/Zn CMM coatings were given on the basis of the analysis on the micrographic features of zinc and Zn-Ni alloy CMM eoatings after the corrosion test. A probable corrosion mechanism of zinc and Zn-Ni alloy CMM coatings was also proposed.

关键词： electrodeposition compositionally modulated multilayer coating Zn-Ni alloy corrosion resistance

Control strategy for multi-pump emulsion power station in coal mine face

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Journal of Coal Science & Engineering(China) 2011年第4期17卷 443-446页

作者： li wen-ying wei Jin-hong Research Institute of Mechano-electronic Engineering Taiyuan University of Technology Taiyuan 030024 China

Shearer and hydraulic support are matching equipments. To increase the operating speed of the shearer, the following speed of hydraulic support must be increased. This means increasing the volume of flow from emulsion power station. Analyzing the operating characteristics of hydraulic supports, the number of simultaneously operating supports is obtained by means of pressure parameter and time history at a certain time, which is a theory base for development of control system to multi-pump emulsion power station.

关键词： emulsion pump mining face hydraulic support control algorithm

Studies on the Crystal Structure and Photoluminescence of a Mercury(Ⅱ)Complex Based on a Novel Pyridine ligand

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Chinese Journal of Structural Chemistry 2010年第7期29卷 1029-1032页

作者： WU Jie-Ying ZHOU wen li wei-Jie ZHOU Hong-Ping TIAN Yu-Peng Department of Chemistry Key Laboratory of Functional Inorganic Materials Chemistry of Anhui Province Anhui University Hefei 230039 China

A novel mercury（H） complex HgL2Br2 was prepared from HgBr2 and the organic ligand 2-（N-methyl-N-（4-（（E）-2-（pyridine-4-yl）vinyl）phenyl）amino）ethanol （L）. The ligand was synthesized and then characterized by FT-IR spectroscopy, tH NMR, mass spectrum and elemental analysis, while the single-crystal diffraction data of the complex were collected on a Siemens Smart CCD diffractometer. The complex crystallizes in triclinic space group PI with a = 5.367（5）, b = 12.466（5）, c = 23.945（5） A, α = 90.812（5）, β = 96.318（4）, γ = 96.093（5）°, Z = 2, Dc = 1.817 ***3,μ = 7.395 mm^-1, S = 0.825, and the final R= 0.0396. The Hg（Ⅱ） ion in the distorted tetrahedral mercury（Ⅱ） complex C32H36HgBr2N4O2 is coordinated by two N atoms from the two ligands together with two bromide ions. Solid-state emission of the ligand and its complex has been investigated at room temperature.

关键词： mercury(Ⅱ) complex single-photon fluorescence crystal structure

Quantitative parameter character of choroidal melanoma in contrast-enhanced ultrasound

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Chinese Medical Journal 2012年第24期125卷 4440-4444页

作者： YANG wen-li wei wen-bin li Dong-jun a Department of Ophthalmology Beijing Tongren Eye Center Beijing Tongren Hospital Capital Medical University Beijing Ophthalmology & Visual Sciences Key Laboratory Beijing 100730 China

Background Choroidal melanoma is the most common intraocular malignant tumor in adults. It threatens not only the visual function but also the patient＇s life. Therefore, it is important to find a non-traumatic, quantitative and repetitive diagnostic method. This study investigated the value of quantitative analysis of contrast-enhanced ultrasound （CEUS） in the diagnosis of choroidal melanoma. Methods CEUS were performed in 51 cases of choroidal melanoma, which were diagnosed either pathologically or clinically and in 14 cases of choroidal hemangioma. The characteristics of the time-intensity curve of the contrast agent were analyzed. For the quantitative analysis, the following parameters of the contrast agent in the lesion were included： rising time （RT）, time to peak （TTP）, maximum intensity （MI） and the mean transit time （MTT）. Results Choroidal melanoma had the following characteristics on CEUS： Choroidal lesions were completely filled with contrast agent. The typical filling pattern was centripetal, with the peripheral of the choroidal lesion filled with the contrast agent first and then the center of the lesion. In some cases, areas with contrast agent filling defect were obseved in the lesions. The contrast agent filled the lesion slower than the normal eye and orbital tissue but faded faster in the lesion. Quantitative analysis showed that in choroidal melanoma, MI of contrast agent （191.31%±146.90%） was significantly more than that of the normal tissue （100.00%±0.00%）（P 〈0.05） and MTT （（63.56±26.04） seconds） was significanly less than that of the normal tissue （（149.87±182.68）seconds）（P 〈0.05）. TTP （22.80±9.85） was less than that of the normal tissue （（29.57±24.76） seconds） and RT （（18.52±7.09） seconds） was less than that of the normal tissue （（26.45±21.83） seconds）. Both the differences of TTP and RT were not statistically significant though. Logistic regression showed that to predict choroidal melanoma and choroidal hemangioma with MI and MTT, the sensi

关键词： choroidal disease malignant melanoma contrast ultrasound diagnosis

Killing effect of Chinese hamster V79 cells exposed to accelerated carbon ions and RBE determination

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Nuclear Science and Techniques 2002年第4期13卷 259-263页

作者： li Qiang, ZHOU Guang-Ming, WANG Ju-Fang, li wen-Jian, wei Zeng-Quan(Institute of Modern Physics, the Chinese Academy of Sciences, Lanzhou 730000) Institute of Modern Physics the Chinese Academy of Sciences Lanzhou 730000

Survival curves of Chinese hamster V79 cells exposed to accclerated carbon ions with linear energy transfers of 125.5, 200 and 700 keV/μm were measured, respectively. Inactivation cross sections corresponding to the irradiation above were deduced from the V79 cell survival curves. They are 7.86±0.17, 10.44±1.11 and 32.32±3.58 μm2 in turn. With the surviving response of V79 cells to 60Co γ-rays as a reference value, relative biological effectiveness at 10%, 20%, 50% and 80% survival levels were given for the accelerated carbon ions. The results showed that carbon ions with LET of 125.5 keV/μm had a higher value of RBE at all the four survival levels than the carbon ions with other LETs. It was prompted that the maximum value of RBE for the V79 cell surviving as the biological endpoint emerged at the LET below 200 keV/μm for carbon ions.

关键词：放射生物学碳离子 V79细胞

Crystalline-fluid melt inclusions in aquamarines in pegmatites of different origins

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Chinese Science Bulletin 1999年第S2期44卷 154-156页

作者： li Zhaolin, li wen and ZHAI wei Department of Earth Science, Zhongshan University, Guangzhou 510275, China Department of Earth Science Zhongshan University Guangzhou 510275 China

THE crystalline-fluid melt inclusions in aquamarines in pegmatites from Mufushan (Hunan Prov.) andAilaoshan (Yunnan Prov.) have been studied. The research shows that there are obvious differences inthe chemical composition of the inclusions in the aquamarines, which is of great importance for studyingthe forming mechanism and origin of pegmatites. 1 General geology of pegmatites Mufushan is situated in the middle sector of the Jiangnan Ancient Land. The granitic pegmatitesmainly outcrop in granite mass of late Yanshanian (105-145 Ma) which was intruded in middle sector ofthe middle Proterozoic strata. Part of the pegmatites occur in the contact zone of the granite and the metamorphic rocks. The pegmatite veins may be divided into four types, all of them were originated from mag-

关键词： crystalline-fluid melt inclusions aquamarine pegmatites origin.

Study of the pulsed working characteristics of the penning ion source for neutron tubes

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Nuclear Science and Techniques 2000年第3期11卷 150-154页

作者： LU Hong-Bo, YUE Cheng-Bo, li wen-Sheng, ZHAI wei-Dong, JIANG Zhong-Jing, wei Bao-Jie (Department of Physis, the Northeast Normal University, Changchun 130024) 西北师范大学甘肃长春 130024

The pulsed working characteristics of the neutron tube ion source were studied experimentally. The principle and method of selecting the gas pressure and anode voltage were determined.

关键词：加速器离子源中子管脉冲宽度阳极电压实验研究