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On the vein-stiffening membrane structure of a dragonfly hind wing

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2009年第1期10卷 72-81页

作者： zhong-xue LI Wei SHEN Gen-shu TONG Jia-meng TIAN Loc VU-QUOC Institute of Structural Engineering Zhejiang University Hangzhou 310058 China Department of Mechanical and Aerospace Engineering University of Florida Gainesville FL 32611 USA

Aiming at exploring the excellent structural performance of the vein-stiffening membrane structure of dragonfly hind wings,we analyzed two planar computational models and three 3D computational models with cambered corrugation based on the finite element *** is shown that the vein size in different zones is proportional to the magnitude of the vein internal force when the wing structure is subjected to uniform out-of-plane transverse *** membrane contributes little to the flexural stiffness of the planar wing models,while exerting an immense impact upon the stiffness of the 3D wing models with cambered *** a lumped mass of 10% of the wing is fixed on the leading edge close to the wing tip,the wing fundamental fre-quency decreases by 10.7%～13.2%;if a lumped mass is connected to the wing via multiple springs,the wing fundamental fre-quency decreases by 16.0%～18.0%.Such decrease in fundamental frequency explains the special function of the wing pterostigma in alleviating the wing quivering *** particular features of dragonfly wings can be mimicked in the design of new-style reticulately stiffening thin-walled roof systems and flapping wings in novel intelligent aerial vehicles.

关键词： Dragonfly wing Venation pattern Wing membrane Pterostigma Bionics Quivering effect

A new protoberberine alkaloid from Corydalis yanhusuo ***

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Chinese Chemical Letters 2009年第8期20卷 955-957页

作者： Tian Tian Hu xue Zhang Shi zhong Ma Xin Sheng Yao School of Traditional Chinese Materia Medica Shenyang Pharmaceutical University Shenyang 110016 China

A new protoberberine alkaloid, named 5,6-dihydro- 10-hydroxy-2,3,9-trimethoxy- 13-methyldibenzo[α,g]quinoliziniurn （1） was isolated from the 60% ethanol extract of the tubers of Corydalis yanhusuo W. T. Wang, together with a new natural product, 13methylpalmatrubine （2）. Their structures were established by spectroscopic methods. 2009 Xin Sheng Yao. Published by Elsevier B.V. on behalf of Chinese Chemical Society. All fights reserved.

关键词： Corydalis yanhusuo W. T. Wang Protoberberine alkaloid 13-Methylpalmatrubine

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World Journal of Gastrointestinal Oncology 2023年第12期15卷 2185-2196页

作者： Jin-Bao Guo Ming Du Bin Wang Li zhong zhong-xue Fu Jin-Lai Wei Department of Thoracic Surgery The First Affiliated Hospital of Chongqing Medical UniversityChongqing 400016China Department of Obstetrics and Gynaecology The First Affiliated Hospital of Chongqing Medical UniversityChongqing 400016China Department of Gastrointestinal Surgery The First Affiliated Hospital of Chongqing Medical UniversityChongqing 400016China

BACKGROUND It is unclear that paired-related homeobox 1(PRRX1)induces epithelialmesenchymal transition(EMT)in oesophageal cancer and the specific function of PRRX1 in oesophageal cancer *** To assess the signicance of PRRX1 expression and investigate the mechanism of EMT in oesophageal cancer *** Detect the expression of PRRX1 by immunohistochemistry in oesophageal tumour tissues and adjacent normal oesophageal tissues;the PRRX1 short hairpin RNA(shRNA)or blank vector lentiviral gene delivery system was transfected into cells;cell proliferation assay,soft agar colony formation assays,cell invasion and migration assays and animal studies were used to observe cells biological characteristics In vitro and in vivo;XAV939 and LiCl were used to alter the activity of Wnt/β-catenin *** staining and western blot analysis were used to detect protein expression of EMT markers and Wnt/β-catenin *** PRRX1 is expressed at high levels in oesophageal cancer specimens and is closely related to tumour metastasis in patients with oesophageal *** of PRRX1 expression might exert obvious effects on cell proliferation,especially the migration and invasion of oesophageal cancer ***,silencing PRRX1 expression using a shRNA produced the opposite *** addition,when PRRX1 was overexpressed,inhibition of the Wnt/β-catenin pathway with XAV939 negated the effect of PRRX1 on EMT,whereas when PRRX1 was downregulated,activation of the Wnt/β-catenin pathway with LiCl impaired the effect on *** PRRX1 is upregulated in oesophageal cancer is closely correlated with cancer ***,PRRX1 induces EMT in oesophageal cancer metastasis through activation of Wnt/β-catenin signalling.

关键词： Paired-related homeobox 1 Oesophageal squamous cancer Epithelial-mesenchymal transition Cancer metastasis

Theoretical Studies on Substituent Effect of the Reaction of Amide and Formaldehyde

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Chemical Research in Chinese Universities 2010年第6期26卷 1007-1010页

作者： LAI Wel-peng LIAN Peng QIU Shao-jun GE zhong-xue WANG Bo-zhou xue Yong-qiang Xi ＇an Modern Chemistry Research Institute Xi ＇an 710065 P. R. China Applied Chemistry Department Taiyuan University of Technology Taiyuan 030024 P. R. China

The thermodynamic properties of the reaction of amide and formaldehyde were calculated via B3LYP method when substituents chosen included CH3,CH2CH3,CH2CH2CH3,CH2CH2CH2CH3,CH（CH3）2,CH2CH（CH3）2,CH（CH3）CH2CH3 and C（CH3）*** on the optimization of the structures for reactants and products,the thermodynamic functions of all the species for an actual state were *** thermodynamic data and the equilibrium constants were investigated within a temperature range of 300―343.15 *** calculated results show that the reaction is exothermic and *** trends of all thermodynamic properties are consistent with the *** preferential order of the substituent effect is CH2CH（CH3）2CH（CH3）CH2CH3CH2CH2CH2CH3 CH2CH2CH3CH2CH3≈CH（CH3）2C（CH3）3≈CH3.

关键词： 1 3 5-Trinitro-1 3 5-triazacyclohexane(RDX) Substituent effect Thermodynamics

Antioxidative Capacity of Irbesartan

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Chemical Research in Chinese Universities 2011年第1期27卷 75-79页

作者： WANG Mei-xue ZHAO xue-zhong GAI Chun-yu LIU Hong-min XU Yan-ping LI Jing The First Hospital 2. School of Public Health Jilin University Changchun 130021 P. R. China The Second Hospital Jilin University Changchun 130041 P. R. China

The author investigated the antioxidant effect of irbesartan[2-butyl-3-（{4-[2-（2H-l,2,3,4-tetrazol-5-yl）. phenyl]phenyl}methyl）-1,3-diazaspiro[4.4]non-1-en-4-one], an angiotensin receptor blocker（ARB）, on the oxidation of erythrocytes induced by 2,2-[azobis（2-amidinopropane） hydrochloride]（AAPH） and H2O2 The value of half concentration（IC50） of irbesartan to scavenge radicals was measured by reacting it with 2,2-[azinobis（3-ethylbenzothia- zoline-6-sulfonate） radical eation]（ABTS＋）. Activities of the catalase（CAT）, superoxide dismutase（SOD）, glutathione peroxidase（GSH-Px） and the content of malondialdehyde（MDA） in liver tissue and blood serum of normal-rats were measured by means of speetrophotometry to study the antioxidation function of irbesartan. Results of experiments show that irbesartan can scavenge ABTS＋ and superoxide radicals effectively as well as inhibit AAPH-, H2O2-induced hemolysis of erythrocytes. Irbesartan can also increase the activities of GSH-Px, SOD, CAT and decrease the content of MDA of normal rats. So irbesartan is a good antioxidant.

关键词： Irbesartan Antioxidant Oxidative stress Radical

Achieving efficient utilization of limonitic nickel laterite and CO_(2) emission reduction through multi-force field sintering process

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Journal of Iron and Steel Research International 2022年第11期29卷 1734-1747页

作者： Yu-xiao xue De-qing Zhu Zheng-qi Guo Jian Pan Yi-ge Wang Qing-zhou Huang Liao-ting Pan xue-zhong Huang School of Minerals Processing and Bioengineering Central South UniversityChangsha 410083HunanChina Guangxi Beibu Gulf New Materials Co. Ltd.Beihai 536000GuangxiChina

Strengthening limonitic nickel laterite sintering and reducing CO_(2) emission were performed by the application of multiforce fields including external thermodynamic and pressure *** pot tests of limonitic nickel laterite were carried out,and the relevant industrial production was *** chemistry and mineralogy of product sinter and the thermodynamic and kinetic conditions during sintering were analyzed to reveal the relevant *** results indicate that sintering performance of limonitic nickel laterite in the new sintering process with multi-force fields is significantly improved with tumble index and productivity increased by 24.11%and 18.56%,respectively,and solid fuel rate reduced by 23.21%,compared with those in traditional sintering *** this case,greenhouse and pollutant gas emissions are greatly reduced,and metallurgical performances of product sinter are *** industrial production has been successfully conducted,indicating a bright application *** analysis shows that the great improvement of thermodynamic and kinetic conditions during sintering and the densification of loose sinter can be achieved via the application of multi-force *** microstructure is transformed from large thin-wall pores to small thin-wall pores or medium thick-wall pores with the dramatic reduction of sinter porosity and more formation of silico-ferrite of calcium and alumina(SFCA).Meanwhile,the homogenization of mineral compositions is achieved,and much denser interlocking texture between hercynite and SFCA is *** application of multi-force fields contributes to the substantial improvement of sintering performance of limonitic nickel laterite and CO_(2) emission reduction.

关键词： Limonitic nickel laterite Multi-force field Sintering performance CO_(2)emission reduction Efficient utilization

Studies on the Conformation of Poly (1-naphthol) Assembled by Horseradish Peroxidase in Aqueous Micelle

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Chemical Research in Chinese Universities 1998年第2期14卷 59-62页

作者： CHEN Song-ming ZHANG xue-zhong CHAI Xiang-dong LI Tie-jin Department of Chemistry the State Key Lab of Enzyme EngineeringJilin UniversityChangchun130023

FTIR, UV-visible , fluorescence spectra and calculation of CPK model indicated that poly(1-naphthol) synthesized and assembled by horseradish peroxidase(HRP) in aqueous micelle was constructed with orderly helical conformation, which was the lowest energy conformation of the polymer under this condition and resulted in an advanced c-conjugated system.

关键词： Conformation Poly(1naphthol) Horseradish peroxidase Aqueous micelle

Lipid Peroxidation and Ultrastructural Modifications in Brain after Perinatal Exposure to Lead and/or Cadmium in Rat Pups

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Biomedical and Environmental Sciences 2009年第5期22卷 423-429页

作者： Yu-MEI ZHANG xue-zhong LIU HAO LU LI MEI ZONG-PING LIU College of Veterinary Medicine Yangzhou University Yangzhou 225009 Jiangsu China College of Veterinary Medicine Northwest Sci-Tech University of Agriculture and Forestry Yangling 712100 Shaanxi China

Objective To assess lipid peroxidation and ultrastructural modifications in rat brains following perinatal exposure to lead （Pb） and/or cadmium （Cd）. Methods Female rats were divided into four groups： control group, Pb （300 mg/L） group, Cd group （10 mg/L） and Pb＋Cd （300 mg/L, 10 mg/L） group. The compounds were delivered in the drinking water throughout pregnancy and lactation. Results The levels of compounds in blood and brain of the Pb＋Cd group were similar to those of other groups, but the effects of Pb＋Cd on pups＇ body and brain weights were higher than on other compounds. Electron microscopy revealed that Pb and Cd had effects on mitochondrial swelling, disruption and cristae loss, Nissl body dissolution, degenerated organelles and vacuoles, cytomembrane disappearance, and nuclear chromoplasm concentration. The activity of glutathione peroxidase （GSH-Px）, superoxide dismutase （SOD）, catalase （CAT）, acetylcholinesterase （ACHE） was decreased, whereas the activity of maleic dialdehyde （MDA） was increased. Conclusion Perinatal exposure to low doses of Pb and Cd can produce alterations in lipid peroxidation and ultrastructural modifications in rat brains, and exposure to both metals can result in greater damages.

关键词： Lead Cadmium Lipid peroxidation Ultrastructure Brain Rat

Research on Computer Simulation System of Stretch Reducing Mill for Tube

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Journal of Iron and Steel Research International 2003年第1期10卷 24-27页

作者： xue zhong-ming QU Wen-qing ZHANG Yan-hua LI Shu-chun Beijing University of Aeronautics and Astronautics Beijing Institute of Mechanical Industry

The prototype,basic parameters,composition and structure of computer simulation system of stretch reducing mill for tubes were *** software has an obvious style of object-oriented programming,and the modules were integrated in the simulation *** system can optimize pass design,and it can automatically classify pass series according to the product syllabus,formulate the rolling table and simulate the rolling parameters in stretch reducing *** simulation results were compared with the detailed technical data(used as experimental data) provided by Baotou Iron and Steel Company,and the comparison gave a clear proof of the precision of the models.

关键词： tube stretch reducing mill pass design force parameter simulation