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Chemical Quenching of Positronium in CuO/Al2O3 Catalysts

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Chinese Physics Letters 2011年第1期28卷 193-196页

作者： ZHANG Hong-Jun LIU Zhe-Wen CHEN zhi-quan wang Shao-Jie Hubei Nuclear Solid Physics Key Laboratory Department of Physics Wuhan University Wuhan 430072

CuO/Al2O3 catalysts were prepared by mixing CuO and environment of the catalysts are characterized by positron v-AI203 nanopowders. Microstrueture and chemical annihilation spectroscopy. The positron annihilation lifetime measurements reveal two long lifetime components 73 and τ4, which correspond to ortho-positronium （o- Ps） annihilating in mierovoids and large pores, respectively. With increasing CuO content from 0 to 40 wt%, both 3-4 and its intensity I4 show significant decrease, which indicates quenching effect of o-Ps. The para-positronium （p-Ps） intensities derived from multi-Gaussian fitting of the coincidence Doppler broadening spectra also decreases gradually with increasing CuO content. This excludes the possibility of spin-conversion of positronium. Therefore, the chemicM quenching by CuO is probably responsible for the decrease of o-Ps lifetime. Variation in the o-Ps annihilation rate A4 （1/T4） as a function of CuO content can be well fitted by a straight line, and the slope of the fitting line is （1.83 ± 0.05） × 10^7 s-1.

关键词： Catalysts Chemicals Measurement

Nucleation Analysis of Variant Transformed from Austenite with Σ_(3) Boundary in High-Strength Low-Alloy Steel

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Acta Metallurgica Sinica(English Letters) 2021年第4期34卷 523-533页

作者： Bin-Bin Wu zhi-quan wang Cheng-Jia Shang Yi-Shuang Yu Devesh Misra Collaborative Innovation Center of Steel Technology University of Science and Technology BeijingBeijing100083China State Key Laboratory of Metal Material for Marine Equipment and Application Anshan114000China Laboratory for Excellence in Advanced Steel Research Department of MetallurgicalMaterials and Biomedical EngineeringUniversity of Texas at El Paso500 WUniversity AvenueEl PasoTX79968USA

We elucidate here the effects of annealing twins on phase transformation products based on electron back-scatter diffraction analysis and corresponding microstructure visualization and quantification *** and bainite were obtained by rapid continuous cooling and isothermal processing at different temperatures,respectively,which were designed to study variants formed in austenite with Σ_(3) *** isothermal transformation near martensite start(M_(s))temperature was most conducive in obtaining the highest content of twin-related V_(1)/V_(2) variant *** on the classical nucleation theory of martensite and bainite,respectively,the role of austenite Σ_(3) boundary in martensite and bainite transformation is illustrated.

关键词： Steel AusteniteΣ_(3)boundary Variant Phase transformation Martensite Bainite

Tailoring Variant Pairing to Enhance Impact Toughness in High-Strength Low-Alloy Steels via Trace Carbon Addition

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Acta Metallurgica Sinica(English Letters) 2021年第6期34卷 755-764页

作者： Yi-Shuang Yu zhi-quan wang Bin-Bin Wu Jing-Xiao Zhao Xue-Lin wang Hui Guo Cheng-Jia Shang Collaborative Innovation Center of Steel Technology University of Science and Technology BeijingBeijing 100083China Key Laboratory for Advanced Materials of Ministry of Education School of Materials Science and EngineeringTsinghua UniversityBeijing 100084China State Key Laboratory of Metal Material for Marine Equipment and Application Anshan 114021China

Alloying can make conventional metals reach ultra-high strength,but this usually comes at dramatic loss of *** this work,a desirable strength–toughness combination in high-strength low-alloy steel achieved via trace carbon *** significance of carbon in tailoring variant pairing and tuning impact toughness was elucidated from the perspective of crystallography and *** the carbon content increases,the packets and blocks are refined,and the-40 impact toughness *** enhancement of impact toughness results from the higher density of block boundaries,and the fracture mode shifts from brittle fracture to ductile–brittle combined fractures,then to ductile fracture due to the increased *** the carbon content would lower the martensite start temperature(M_S)temperature and driving force for martensitic transformation,and increase the strength of austenite matrix,which in turn contributes to producing more V1/V2 variant pairs to accommodate the transformation strain.

关键词： High-strength low-alloy steel Carbon Impact toughness Variant pairing Phase transformation

Facilitating effects of berberine on rat pancreatic islets through modulating hepatic nuclear factor 4 alpha expression and glucokinase activity

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World Journal of Gastroenterology 2008年第39期14卷 6004-6011页

作者： zhi-quan wang Fu-Er Lu San-Hua Leng Xin-Sheng Fang Guang Chen Zeng-Si wang Li-Ping Dong Zhong-Qing Yan Institute of Integrated Traditional Chinese and Weestern Medicine Tongji Hospital Tongji Medical College Huazhong University of Science and Technology Wuhan 430030 Hubei Province China

AIM： To observe the effect of berberine on insulin secretion in rat pancreatic islets and to explore its possible molecular mechanism. METHODS： Pdmary rat islets were isolated from male Sprague-Dawley rats by collagenase digestion and treated with different concentrations （1, 3, 10 and 30 μmol/L） of berberine or 1 μmol/L Glibenclamide （GB） for 24 h. Glucose-stimulated insulin secretion （GSIS） assay was conducted and insulin was determined by radioimmunoassay. 3-（4,5-Dimethylthiazol-2-yl）- 2,5-diphenyltetrazolium bromide （MTT） assay was performed to evaluate cytotoxicity. The mRNA level of hepatic nuclear factor 4 alpha （HAIF4α） was determined by reverse transcription polymerase chain reaction （RT-PCR）. Indirect immunofluorescence staining and Western blot analysis were employed to detect protein expression of HNF4α in the islets. Glucokinase （GK） activity was measured by spectrophotometric method. RESULTS： Berberine enhanced GSIS rather than basal insulin secretion dose-dependently in rat islets and showed no significant cytotoxicity on islet cells at the concentration of 10 μmol/L. Both mRNA and protein expressions of HNF4α were up-regulated by berberine in a dose-dependent manner, and GK activity was also increased accordingly. However, GB demonstrated no regulatory effects on HNF4α expression or GK activity. CONCLUSION： Berberine can enhance GSIS in rat islets, and probably exerts the insulinotropic effect via a pathway involving HNF4α and GK, which is distinct from sulphonylureas （SUs）.

关键词： Berberine Sulphonylureas Hepatocyte nuclear factor 4 alpha Glucokinase Pancreatic islet

The role of DJ-1 in the pathogenesis of Parkinson’s disease

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Neuroscience Bulletin 2006年第4期22卷 232-234页

作者： zhi-quan wang Hai-Yan ZHOU Sheng-Di CHEN Institute of Health Science Shanghai Institutes for Biological Sciences of Chinese Academy of Sciences and Shanghai Jiaotong University School of Medicine Shanghai 200025 China Department of Neurology and Institute of Neurology Ruijin Hospital Shanghai Jiaotong University School of Medicine Shanghai 200025 China

Parkinson’s disease (PD) is a slowly progressive neurodegenerative disorder characterized clinically by bradykinesia, rigidity, tremor, gait dysfunction, and postural instability. Several genes have been identified for monogenic disorders that variably resemble Parkinson’s disease. Here, we focus on PARK7, a gene relates to an autosomal recessive form of early-onset Parkinsonism and encodes a protein named DJ-1. Though the exact role of DJ-1 needs to be elucidated, it is generally thought to be functioned as a molecular chaperone and an oxidative sensor (or antioxidative factor). We will review the protective role of DJ-1 to prevent dopaminergic neurons in the substantia nigra pars compacta (SNpc) from degeneration and how its dysfunction would lead to neurodegeneration.

关键词： Parkinson's disease D J- 1 molecular chaperone antioxidative factor

A Novel BIST Approach for Testing Input/Output Buffers in SoCs

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Journal of Electronic Science and Technology of China 2009年第4期7卷 322-325页

作者： Lei Chen zhi-Ping Wen zhi-quan Zhang Min wang Beijing Microelectronics Technology Institution Beijing 100076 China

A novel built-in self-test （BIST） approach to test the configurable input/output buffers in Xilinx Virtex series SoCs （system on a chip） using hard macro has been proposed in this paper. The proposed approach can completely detect single and multiple stuck-at gate-level faults as well as associated routing resources in I/O buffers. The proposed BIST architecture has been implemented and verified on Xilinx Virtex series FPGAs （field programmable gate configurations are required array）. Only total of 10 to completely test the I/O buffers of Virtex devices.

关键词： Built-in self-test FPGA I/O buffers SoCs testing.

Use of endoscopic naso-pancreatic drainage in the treatment of severe acute pancreatitis

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World Journal of Gastroenterology 2003年第4期9卷 868-870页

作者： Zhu-Fu quan zhi-Ming wang Wei-Qin Li Jie-Shou Li Research Institute of General Surgery,Jinling Hospital,Medical College of Nanjing University,Nanjing 210002,Jiangsu Province,China Institute of General Surgery Jinling Hospital Medical College of Nanjing University Nanjing 210002 Jiangsu Province China. quanzf@***

AIM: To review the experience on the use of endoscopic nasopancreatic drainage (ENPD) in the treatment of severe acute pancreatitis (SAP).METHODS: Since March 1998, under the regular management of SAP with non-operative method, ENPD has been randomly used in 14 patients. The average age of the patients was 41.3±15.9 (years), with 8 males and 6 *** time from onset to admission was 32.9±22.8 (hours). 8cases were found to have gallbladder stone. The daily output of pancreatic fluid was measured. The body temperature,heart rate, WBC count, blood glucose, blood calcium, PaO2,blood and urine levels of amylase were detected on the fifth day and compared with their respective data on the first *** results and hospitalization times were ***: The time of drainage was 7.3±4.0 days. The daily drainage outputs of the first five days were 236.4±176.6,287.1±164.7, 284.6±216.4, 435.0±357.8 and 377.8±223.8 ml,respectively. The decreases in body temperature, heart rate,WBC counts, blood and urine levels of amylase and the increase in PaO2 were significant on the fifth day when compared with those on the first day. Infection of pancreatic necrosis was found in one patient and controlled by antiinfectives. 6 out of 8 patients with gallbladder stone were operated during hospital stay. All patients were cured and diischarged and the average hospital stay was 28.1±11.6 ***: ENPD is an effective method for the drainage of pancreatic fluid and might have an important role in the treatment of SAP. Further observation, comparison and summary by this method are worthy to be considered.

关键词：重症急性胰腺炎外科治疗内镜手术鼻-胰腺引流术急腹症

Prediction and optimization of flue pressure in sintering process based on SHAP

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International Journal of Minerals,Metallurgy and Materials 2025年第2期32卷 346-359页

作者： Mingyu wang Jue Tang Mansheng Chu quan Shi Zhen Zhang School of Metallurgy Northeastern UniversityShenyang 110819China Liaoning Low-Carbon Steelmaking Technology Engineering Research Center Northeastern UniversityShenyang 110819China Engineering Research Center of Frontier Technologies for Low-Carbon Steelmaking(Ministry of Education) Shenyang 110819China

Sinter is the core raw material for blast *** pressure,which is an important state parameter,affects sinter *** this paper,flue pressure prediction and optimization were studied based on the shapley additive explanation(SHAP)to predict the flue pressure and take targeted adjustment ***,the sintering process data were collected and processed.A flue pressure prediction model was then constructed after comparing different feature selection methods and model algorithms using SHAP+extremely random-ized trees(ET).The prediction accuracy of the model within the error range of±0.25 kPa was 92.63%.SHAP analysis was employed to improve the interpretability of the prediction *** effects of various sintering operation parameters on flue pressure,the relation-ship between the numerical range of key operation parameters and flue pressure,the effect of operation parameter combinations on flue pressure,and the prediction process of the flue pressure prediction model on a single sample were analyzed.A flue pressure optimization module was also constructed and analyzed when the prediction satisfied the judgment *** operating parameter combination was then *** flue pressure was increased by 5.87%during the verification process,achieving a good optimization effect.

关键词： sintering process flue pressure shapley additive explanation prediction optimization

Acute aortic occlusion as an unusual embolic complication of cardiac myxoma

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Chinese Medical Journal 2006年第4期119卷 342-344页

作者： ZHANG Jian DUAN zhi-quan wang Chuan-jiang SONG Qing-bin LUO Ying-wei XIN Shi-jie Department of Vascular Surgery First Affiliated Hospital of China Medical University Shenyang 110001 China

Acute aortic occlusion is an infrequent but dangerous vascular emergency with a mortality rate of 50%, resulting from aortic saddle embolus, thrombosis of an atherosclerotic abdominal aorta, or sudden thrombosis of a... 详细信息

关键词： myxoma embolization