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Synthesis and structure characterization of a novel series of N-alkylphthalimidylaminocarbonylmethoxylcalix[4]arenes

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Chinese Chemical Letters 2007年第12期18卷 1493-1495页

作者： Zhi Qiang Shi Ya Qing Feng Bing zhao wen Xiang wang School of Chemical Engineer and Technology Tianjin University Tianjin 300072 China

A novel series of N-alkylphthalimidylaminocarbonylmethoxylcalix[4]arenes with the reaction between 4-（N-bromoacetyla- mino）-phthalimide derivatives and calix[4]arene has been synthesized and structurally characteriz... 详细信息

关键词： Calixarene 4-(N-Bromoacetylamino)-phthalimide Fluorescent

Bit error probability of distributed Turbo coded relay systems over quasi-static Rayleigh fading channels

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The Journal of China Universities of Posts and Telecommunications 2010年第2期17卷 41-45页

作者： PENG Yue-xing WU Mu-zi zhao Hui wang wen-bo Wireless Signal Processing and Network Laboratory Key Lab of Universal Wireless Communications Ministry of Education School of Information and Communication Engineering Beijing University of Posts and Telecommunications Beijing 100876 China

As is known, distributed Turbo coding （DTC） performs close to the theoretic outage probability bound of a relay channel when correct decoding is assumed at the relay. However, decoding error is inevitable in practical fading channels due to the error-prone feature of radio channels, and the decoding error propagation in DTC scheme will severely degrade the error performance of the relay system. As a result, it is necessary to evaluate the error performance of the DTC scheme in multi-hop relaying wireless systems in practical fading channels. Moreover, the theoretical method of analysis provides an effective tool for obtaining the error performance besides lengthy simulations. In this article, the concept of equivalent signal-to-noise ratio （SNR） of the two-hop relay channel and the method of computing equivalent SNR are developed, and then the upper bound on the bit error probability （BEP） of DTC relay systems is analyzed by use of Turbo code＇s distance spectrum, the concept of uniform interleaver, the limit-before-averaging technique, and the union bound method. Both theoretical analysis and numerical simulation are implemented for relay systems with DTC scheme over quasi-static Rayleigh fading channels. The results show that the upper bound approaches the simulation results in the medium to high SNR region.

关键词： bit error probability distributed Turbo code relay network union bound distance spectrum SNR

Nuclear Effect Study Under K Factor's Nonconstancy

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Communications in Theoretical Physics 2002年第7期38卷 59-64页

作者： HOU zhao-Yu WU wen-wang HE Ming-Zhong ZHANG Ben-Ai Department of Physics Shijiazhuang Normal College Shijiazhuang 050801 China Graduate School the Chinese Academy of Engineering Physics Beijing 100088 China Department of Mathematics and Physics Shijiazhuang Railway College Shijiazhuang 050043 China Department of Electronics Hebei Normal University Shijiazhuang 050016 China Graduate School the Chinese Academy of Engineering Physics Beijing 100088 China

A consistent approach to estimating nuclear effect functions RA RvA (x2) and RSA(x2) based on numerical iteration technique is presented in the quark-parton model when taking into account the nonconstancy of quantum chromodynamics correction factor K. ARv (x2) and RsA(x2) correspond respectively to the valence quark distributions for one bound nucleon within the nucleus and to the sea quark ones. Related numerical analysis is given for nuclei 6 12C,20 40Ca, and 26 56Fe. As the basis, it adopts both experimental data of the high energy proton-nucleus Drell-Yan process and of the high energy lepton-nucleus deep inelastic scattering.

关键词： K-factor, Drell-Yan process, deep inelastic scattering, nuclear parton distribution

A new contact material—Ag/SnO_2-La_2O_3-Bi_2O_3

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Rare Metals 2002年第4期21卷 289-293页

作者： LU Jianguo, wang Jingqin, zhao Jingying, wen Ming, wang Baozhu, and wang XiaohongInstitute of Electrical Apparatus, Hebei University of Technology, Tianjin, 300130, China Institute of Electrical Apparatus Hebei University of Technology 天津 300130 Institute of Electrical Apparatus Hebei University of Technology Tiaojin 300130

A super-fine compound powder, Ag/SnO_2+La_2O_3+ Bi_2O_3, has been obtainedusing the chemical coprecipitation method. And a new contact material, Ag/SnO_2+La_2O_3+Bi_2O_3, wasproduced by the powder metallurgy method. Its properties are as follows: the density is 9.75-9.93g/cm^3, the resistivity is 2.31-2.55 μΩ ·cm, the hardness is 880-985 MPa. Its mi-crostructureshows that the fine oxides have a uniform distribution in the silver matrix. The results ofmake-break capacity and temperature rise testing show that the new material has better ability ofanti-arc erosion and lower temperature rise than that of commonly used Ag/CdO.

关键词： contact material silver rare earth oxide powder metallurgy microstructure additive

Neuroprotective mechanisms of rutin for spinal cord injury through anti-oxidation and anti-inflammation and inhibition of p38 mitogen activated protein kinase pathway

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Neural Regeneration Research 2018年第1期13卷 128-134页

作者： Hong-liang Song Xiang Zhang wen-zhao wang Rong-han Liu Kai zhao Ming-yuan Liu Wei-ming Gong Bin Ning Department of Spinal Surgery Jinan Central Hospital Affiliated to Shandong University Hospital Pharmacy Jinan Central Hospital Affiliated to Shandong University Department of Gynecology and Obstetrics Jinan Maternity and Child Care Hospital

Rutin has anti-inflammatory, antioxidant, anti-viral, anti-tumor and immune regulatory effects. However, the neuroprotective effects of rutin in spinal cord injury are unknown. The p38 mitogen activated protein kinase （p38 MAPK） pathway is the most important member of the MAPK family that controls inflammation. We assumed that the mechanism of rutin in the repair of spinal cord injury is associated with the inhibition of p38 MAPK pathway. Allen’s method was used to establish a rat model of spinal cord injury. The rat model was intraperitoneally injected with rutin （30 mg/kg） for 3 days. After treatment with rutin, Basso, Beattie and Bresnahan locomotor function scores increased. Water content, tumor necrosis factor alpha, interleukin 1 beta, and interleukin 6 levels, p38 MAPK protein expression and caspase-3 and -9 activities in T8–9 spinal cord decreased. Oxidative stress related markers superoxide dismutase and glutathione peroxidase levels increased in peripheral blood. Rutin exerts neuroprotective effect through anti-oxidation, anti-inflammation, anti-apoptosis and inhibition of p38 MAPK pathway.

关键词： nerve regeneration spinal cord injury rutin oxidative stress antioxidant anti-inflammation p38 mitogen activated protein kinase pathway anti-apoptosis caspase-3 caspase-9 neural regeneration

Phosphatases of regenerating liver： a novel target in human solid tumors

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Chinese Medical Journal 2008年第15期121卷 1469-1474页

作者： zhao wen-bo wang Xin Department of Hematology Provincial Hospital Shandong University Jinan Shandong 250021 China

Protein tyrosine phosphorylation is a major posttranslational modification used by cells to regulate signal transduction and essentially participate in every aspect of cellular physiologic and pathogenic processes. The protein tyrosine phosphatase （PTP） super family of enzymes coordinately function with protein tyrosine kinases in signaling pathways that underlie a broad spectrum of fundamental physiological processes. Abnormal regulation of tyrosine phosphorylation or deregulation of phosphorylation is known to result in neoplastic or non-neoplastic diseases. Having evolved into separate families that are structurally and mechanistically distinct, PTPs have been implicated in a variety of diseases and efforts have been made to seek therapeutic clues from them. The phosphatases of regenerating liver （PRL） PRL-1, PRL-2, PRL-3 （also known as PTP4A1, PTP4A2, and PTP4A3, respectively） constitute a subfamily of the protein tyrosine phosphatases that have been suggested to play a key role in oncogenic and metastatic phenotypes.5 Here we review what is known about this novel class of small, prenylated phosphatases and its value in diagnosis and therapy of solid tumors.

关键词： phosphatases of regenerating liver tumor invasion metastasis angiogenesis

Process Control for Structure of Martensite/Austenite Islands of 15.3 mm X100 Pipeline Steel in BX Steel

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Journal of Iron and Steel Research International 2011年第S1期18卷 487-491页

作者： XU Xue-li,zhao Ke,zhao Di,wang wen-fei (Technical Center of BX Steel,Benxi 117000,Liaoning,China) Tech Ctr BX Steel Benxi 117000 Liaoning Peoples R China

This paper mainly studies the influence of deformation amount and cooling rate,which existed in X100 pipeline steel rolled at 2300mm rolling mill in BX STEEL,on morphology,size relations and distribution of M/A islands of steel plate *** results show that structures of M/A islands are homogenized and refined under the conditions of appropriately increasing the deformation amount in non-recrystallization region on basis of rational deformation amount in recrystallization region and cooling rate after deformation,***,according to the actual situation of 2300mm hot rolling mill,this paper gives rational deformation amount and cooling rate used to obtain ideal structure of M/A islands.

关键词： X100 pipeline steel martensite/austenite (M/A) islands deformation amount cooling rate

Raman spectroscopy and quantum chemical calculation on YCl_(3)-KCl molten salt system

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Rare Metals 2023年第11期42卷 3886-3896页

作者： Can Xu Xian-Wei Hu Jiang-Yu Yu Peng-Wei Li Ai-Min Liu Shao-Hua Luo Zhong-Ning Shi zhao-wen wang Key Laboratory Ecological Metallurgy of Multimetallic Mineral‘Ministry of Education’ School of MetallurgyNortheastern UniversityShenyang110819China State Key Laboratory of Rolling and Automation Northeastern UniversityShenyang110819China School of Materials Science and Engineering Northeastern UniversityShenyang110819China Department of Chemistry and Bioscience Aalborg University9220AalborgDenmark

The knowledge on the ionic structure of YCl_(3)-KCl molten system is of guiding significance for the practical production of yttrium metals and yttrium alloys via molten salt electrolysis using this system as *** this paper,the theoretical Raman spectra of the ionic groups which may exist in YCl_(3)-KCl molten system are simulated by quantum chemical calculation using Gaussian09 and Gauss View 5.0 programs based on density functional theory(DFT).Then the ionic structures of 20 mol%-60 mol%YCl_(3)-KCl molten salt systems are studied by comparing the Raman shift values of the bands in the theoretical Raman spectra of different ionic groups with the experimental spectra of this ***_(6)^(3-),Y_(2)Cl_(7)^(-),Y_(2)Cl_(8)^(2-)and Y_(2)Cl_(9)^(3-)are thought to exist in the molten *** the increase of temperature,the relative content of YCl_(6)^(3-)ionic groups increases while those of Y_(2)Cl_(7)^(-),Y_(2)Cl_(8)^(2-)and Y_(2)Cl_(9)^(3-)ionic groups ***,the"lifetime"of all ionic groups decreases within the temperature range of 692-730℃.Meanwhile,the relative contents of Y_(2)Cl_(7)^(-),Y_(2)Cl_(8)^(2-)and Y_(2)Cl_(9)^(3-)increase with the increase of YCl_(3)content,while that of YCl_(6)^(3-)*** wave function analysis of the four ionic groups(YCl_(6)^(3-),Y_(2)Cl_(7)^(-),Y_(2)Cl_(8)^(2-),and Y_(2)Cl_(9)^(3-))is carried out by Multiwfn *** net charge in each group,the direction of electron migration during the formation of each group,the sites where electrophilic and nucleophilic reactions are most likely to occur in each ionic group,and the order of bond breaking during chemical reactions for the four groups are obtained.

关键词： YCl_(3)-KCl molten salt Ionic structure Raman spectroscopy Quantum chemical calculation Wave function analysis

A light-through-side cell and co-used furnace designed for micro-Raman spectra study on volatile melts

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Chinese Chemical Letters 2012年第11期23卷 1291-1294页

作者： Xian Wei Hu Huan Li Bing Liang Gao Jing Jing Liu Zhong Ning Shi Jiang Yu Yu zhao wen wang School of Materials and Metallurgy Northeastern UniversityShenyang 110004China

A new type of sample cell specially designed for micro-Raman spectra study on volatile melts is described. The cell is made of quartz. The lower section of the cell is circular ring-shaped and the one-end-closed hole in the cell is used for locating the heating body. The tube attached to the cell lid for placing the thermal couple is inserted into the sample, which ensures that the temperature measurement accuracy is good. The cell can be sealed for reducing the effect of the composition change caused by the in_homogeneous volatilization. During the Raman spectra scanning, the laser beam is transmitted into the cell through the side but not the top. Meanwhile, a furnace has been designed to match the cell. The heating body is closely coupled with the sample cell, and there is a hole on the side wall of the furnace for the entrance of the microlens. The assembly has performed well in the tested Raman spectrum measurement of molten NaNO3 at 602 ℃.

关键词： Light-through-side cell Raman spectroscopy Volatile melts Comer microlens Cell-around-heating body furnace