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Friction Wear Property of Brake Materials by Copper-based Powder Metallurgy With Various Brake Speeds

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材料热处理学报 2004年第5期25卷 126-129页

作者： LIUJian-xiu GAOHong-xia WEIxiu-lan ZhengzhouUniversityofLightIndustry. MechanicalEngineeringInstituteZhengzhouChina

The experiment is conducted on MM-1000 friction test machine, which tests friction wear property of copper-based brake materials by powder metallurgy at different brake speeds. It shows that the coefficient of friction and wear volume are greatly influenced by brake speed. When the brake speed is 4000 r/min, which is a bit higher, the material still has a higher coefficient of friction with 0.47. When the brake speed is over 4000r/min, the coefficient of friction decreased rapidly. When the brake speed is 3000r/min, the material’s wear is in its minimum. That is to say no matter how higher or lower the brake speed is the wear volume is bigger relatively. With the brake speed of the lower one it mainly refers to fatigue wear; while of higher one it mainly refers to abradant and oxidation wear.

关键词：粉末冶金刹车铜材料磨损

Experimental Study of Isopropanol Dehydrogenation over Amorphous Alloy Raney Nickel Catalysts

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Journal of Thermal Science 2013年第6期22卷 613-618页

作者： XIN Fang XU Min LI Xun-Feng HUAI xiu-lan Institute of Engineering Thermophysics Chinese Academy of Sciences University of Chinese Academy of Sciences

The dehydrogenation reaction of isopropanol occurring at low temperature is of great industrial importance. It is a key procedure in isopropanol/acetone/hydrogen chemical heat pump system. An experimental investigation was performed to study the behavior of the liquid phase dehydrogenation of isopropanol over amorphous alloy Raney nickel catalysts. Un-promoted and promoted catalysts were used and their performances were compared under various catalyst amounts, acetone content in the reactant and reaction temperature ranging from 348 K to 355 *** is found that there exists an optimum catalyst concentration which is about 0.34 g in 300 ml isopropanol. The temperature has evident effect on the reaction. The presence of activities of Fe-promoted catalyst decrease slightly compared to the un-promoted catalyst when the temperature are 348 K and 351 K. Besides, the reaction rate decreases almost linearly with the increase of acetone volume fraction in the reactant.

关键词： Chemical heat pump Liquid-phase dehydrogenation Isopropanol

Tissue factor with age-related macular degeneration

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International Journal of Ophthalmology(English edition) 2012年第5期5卷 609-613页

作者： Guan-Feng Wang xiu-lan Zou Department of Ophthalmology Guangzhou General Hospital of Guangzhou Military Command Guangzhou 510010 Guangdong Province China Jinan University Guangzhou 510630 Guangdong Province China

Wet age-related macular degeneration which incidence increases year by year is a blinding eye disease, but current clinical methods of treatment on this disease are limited and the outcome is not ideal. Recent studies have found abnormally high expression of tissue factors which are targets for the treatment of wet age-related macular degeneration to achieve a certain effect in the choroidal neovascularization. Related literatures are reviewed as following.

关键词： wet age-related macular degeneration choroidal neovascularzation tissue factor photodynamic therapy immunotherapy

A new cytotoxic bufadienolide from Chinese medicine Chansu

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Chinese Chemical Letters 2008年第12期19卷 1445-1446页

作者： xiu lan Xin Rong lan Jian Huang Xiao Jie Wang Jing Ming Jia School of Traditional Chinese Medicines Shenyang Pharmaceutical University Shengyang 110016 China Beijing Vocational College of Electronic Science and Technology Beijing 100029 China

A new cytotoxic bufadienolide was isolated from the traditional Chinese medicine-Chansu. The structure of new compound was elucidated on the basis of spectral methods including 2D NMR. And it showed strong in vitro cy... 详细信息

关键词： Bufadienolide Steroid Cytotoxicity Chansu

Downregulation of survivin by RNAi inhibits growth of human gastric carcinoma cells

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World Journal of Gastroenterology 2007年第8期13卷 1170-1174页

作者： Guo-Ying Miao Qi-Ming Lu xiu-lan Zhang Department of Digestion The People's Hospital of Gansu Province Lanzhou 730000 Gansu Province China

AIM: To investigate the inhibitory effect of a specific small survivin interfering RNA (siRNA) on cell proliferation and the expression of survivin in human gastric carcinoma cell line SGC-7901. METHODS: To knockdown survivin expression, a small interfering RNA targeting against survivin was synthesized and transfected into SGC-7901 cells with lipofectamineTM2000. The downregulation of survivin expression at both mRNA and protein levels were detected by reverse transcription-polymerase chain reaction (RT-PCR) and Western blot analysis. Cell proliferation inhibition rates were determined by methyl thiazolyl tetrazolium (MTT) assay. The effect of survivin siRNA on cell cycle distribution and cell apoptosis was determined by flow cytometry (FCM). RESULTS: RNA interference could efficiently suppress the survivin expression in SGC-7901 cells. At 48 h after transfection, the expression inhibition rate was 44.52% at mRNA level detected by RT-PCR and 40.17% at protein level by Western blot analysis. Downregulation of survivin resulted in significant inhibition of tumor cell growth in vitro. The cell proliferation inhibition rates at 24, 48 and 72 h after survivin siRNA and non-siliencing siRNA transfection, were 34.06%, 47.61% and 40.36%, respectively. The apoptosis rate was 3.56% and the number of cells was increased in G0/G1 phase from 38.2% to 88.6%, and decreased in S and G2/M phase at 48 h after transfection. CONCLUSION: Downregulation of survivin results in significant inhibition of tumor growth in vitro. The inhibition of survivin expression can induce apoptosis of SGC-7901 cells. The use of survivin siRNA deserves further investigation as a novel approach to cancer therapy.

关键词： Gastric carcinoma Survivin RNA interference Apoptosis Gene expression

NQO1 C609T polymorphism correlated to colon cancer risk in farmers from western region of Inner Mongolia

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Chinese Journal of Cancer Research 2012年第4期24卷 317-322页

作者： xiu-lan Su Mei-Rong Yan Ling Yang Qimuge-Suyila Clinical Medical Research Center of the Affiliated Hospital Inner Mongolia Medical College

Objective： To investigate the relationship between NAD（P）H：quinone oxidoreductase 1 （NQOI） C609T polymorphism and colon cancer risk in farmers from western region of Inner Mongolia. Methods： Polymerase chain reaction-restriction fragment length polymorphism （PCR-RFLP） was performed to analyze NQO1 C609T polymorphism from 160 healthy controls and 76 colon cancer patients. Results： Among the colon cancer patients, the incidence of NQOI T allele （53.29%） was significantly higher than it in control group （33.75%, P〈0.001）. The individuals with NQO1 T allele had higher risk [2.239 （95% CI： 1.510-3.321） times] to develop colon cancer than individuals with NQO1 C allele. The incidence of NQO1 （TFI-）（34.21%） in colon cancer patients was higher than that in control group （15.62%, P〈0.001）. Odds ratios （OR） analysis suggested that NQO1 （T/F） and NQOI （T/C） genotype carriers had 3.813 （95% CI： 1.836-7.920） times and 2.080 （1.026-4.219） times risk compared with wild-type NQO1 （C/C） gene carriers in developing colon cancer. Individuals with NQO1 （T/I＇） genotype had 2.541 （95% CI： 0.990-6.552） times, 3.713 （95% CI： 1.542-8.935） times, and 3.471 （95% CI： 1.356-8.886） times risk than individuals with NQOI （T/C） or NQOI （C/C） genotype in well- differentiated, moderately-differentiated, and poorly-differentiated colon cancer patients, respectively. Conclusions： NQO1 gene C609T could be one of risk factors of colon cancer in farmers from western region of Inner Mongolia,

关键词： Colon cancer NAD(P)H:quinone oxidoreductase 1 gene polymorphism Inner Mongolia

Uniquely Strongly Clean Group Rings

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Communications in Mathematical Research 2012年第1期28卷 17-25页

作者： WANG xiu-lan Department of Mathematics Harbin Institute of Technology Harbin 150001

A ring R is called clean if every element is the sum of an idempotent and a unit, and R is called uniquely strongly clean （USC for short） if every element is uniquely the sum of an idempotent and a unit that commute. In this article, some conditions on a ring R and a group G such that RG is clean are given. It is also shown that if G is a locally finite group, then the group ring RG is USC if and only if R is USC, and G is a 2-group. The left uniquely exchange group ring, as a middle ring of the uniquely clean ring and the USC ring, does not possess this property, and so does the uniquely exchange group ring.

关键词： clean ring group ring p-group USC ring

Sand-bed defect recognition for 3D sand printing based on deep residual network

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China Foundry 2021年第4期18卷 344-350页

作者： lan-xiu Wang Xuan-pu Dong Shu-ren Guo State Key Laboratory of Materials Processing and Die&Mould Technology School of Materials Science and EngineeringHuazhong University of Science and TechnologyWuhan 430074China

The 3D sand printing(3DSP),by binder jetting technology for rapid casting,has a pivotal role in promoting the development of the traditional casting industry as a result of producing high-quality and economical sand *** work presents an approach for monitoring and analyzing powder sand-bed images to serve as a real-time control system in a 3DSP machine.A deep residual network(ResNet)is used to classify the defects occurring during the powder spreading stage of the ***,a pre-trained network was applied as the initial parameter;then it was fine-tuned on the labelled defective sample dataset to accomplish the task,which defines the sand-bed defects induced in the 3DSP ***,the recognition and positioning of sand-bed defects were readily achieved by dividing the sand-bed images into *** show that the fine-tuned network has a 98.7%classification accuracy on the validation dataset of sand-bed defects and 95.4%recognition accuracy for the sand-bed images.

关键词： 3D sand printing sand-bed defects deep residual network sand-bed images

TRPC6:an underlying target for human glaucoma

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International Journal of Ophthalmology(English edition) 2012年第4期5卷 523-526页

作者： Qian Fan Wen-Bin Huang and xiu-lan Zhang Zhongshan Ophthalmic Center State Key Laboratory of Ophthalmology Sun Yat-sen University Guangzhou 510060 Guangdong Province China

Glaucoma is one of the leading causes of visual impairment and blindness worldwide. Of known risk factors for glaucoma, an increased in intraocular pressure is most highly correlated with glaucomatous damage. Irrespective of the cause, apoptosis of the retinal ganglion cells is the eventual outcome. It is widely accepted that glaucoma is a neurodegenerative disease that is strongly correlated with central nervous system disorders, such as Alzheimer's disease. These two disorders also share some similarities in pathogenic mechanisms. Recent studies suggest that the transient receptor potential canonical 6 channel could work together with brain-derived neurotrophic factor to promote neuron survival in brain and retina. In this study, we propose that transient receptor potential canonical 6 may contribute to the pathogenesis of human glaucoma and become a potential therapeutic target.

关键词： glaucoma transient receptor potential canonical 6 channel neuroprotection