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Defence Technology（防务技术） 2023年第6期24卷 203-213页

作者： Ke-xin Wang li-xiao shen Bin Yuan Yan li Shun-guan Zhu lin Zhang Zhen-xin Yi Chen-guang Zhu School of Chemistry and Chemical Engineering Nanjing University of Science and TechnologyNanjing210941China

Energetic metal-organic complexes have been involved in nanothermites as novel ***,the existing preparation methods often lead to mixing inhomogeneity and small contact area of ingredients,the reactivity and functionality of the novel energetic nanocomposites are still *** this work,spray crystallization(SC)method was used to prepare novel energetic nanocomposites,the high-energy metal-organic complex[Ni(CHZ)_(3)](ClO_(4))_(2)(CHZ=1,3-diaminourea)was composited with nanoaluminum(n-Al).Results showed that n-Al/[Ni(CH_(2))_(3)](ClO_(4))_(2)energetic nanocomposites prepared by SC method increased heat release to 2977.6 J/g and peak pressure to 3.91 MPa with higher pressurization rate(1324.06 MPa/s),decreased sensitivity thresholds(>100 mJ)to electrostatic discharge(ESD)and enhanced detonation ability compared with[Ni(CHZ)_(3)](ClO_(4))_(2)alone and physically mixed(PM)n-Al/[Ni(CHZ)_(3)](ClO_(4))_(2).These results proved that it is significant to introduce energetic metal-organic complexes with inherent high energy in new-concept n-Al/energetic metal-organic complexes nanocomposites through SC method for a better performance of its application.

关键词： Energetic metal-organic complexes Nano aluminum Energetic nanocomposites Spray crystallization Thermite reaction

Recent advances in Pt catalysts and membrane electrode assemblies fabrication for proton exchange membrane fuel cells

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Rare Metals 2024年第9期43卷 4198-4221页

作者： Miao Ma li-xiao shen Jing liu Bin Xu Yun-Long Zhang Lei Zhao Zhen-Bo Wang School of Chemistry and Chemical Engineering Harbin Institute of TechnologyHarbin 150001China College of Environmental and Chemical Engineering Yanshan UniversityQinhuangdao 066004China Unipower Hydrogen Technology(Jiangsu)Corporation Changzhou 213176China

Proton exchange membrane fuel cells(PEMFCs)have been identified as a highly promising means of achieving sustainable energy conversion.A crucial factor in enhancing the performance of PEMFCs for further potential energy applications is the advancement in the field of catalyst engineering that has led to remarkable performance enhancement in facilitating the oxygen reduction reaction(ORR).Subsequently,it is important to acknowledge that the techniques used in preparation of membrane electrode assemblies(MEAs),the vital constituents of PEMFCs,also possess direct and critical influence on exhibiting the full catalytic activity of meticulously crafted ***,a succinct summary of the most recent advancements in Pt catalysts for ORR was offered and their underly catalytic mechanism were ***,both laboratory-scale and industrial-scale MEA fabrication techniques of Pt catalysts were ***,a detailed analysis of the connections between materials,process,and performance in MEA fabrication was presented in order to facilitate the development of optimal catalyst layers.

关键词： Pt catalysts Oxygen reduction reaction Membrane electrode assemblies MEA fabrication techniques

Patterns of floristic inventory and plant collections in Myanmar

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Plant Diversity 2023年第6期45卷 302-308页

作者： Thant Sin Aung Alice CHughes Phyo Kay Khine Bo liu xiao-li shen Ke-Ping Ma State Key Laboratory of Vegetation and Environmental Change Institute of BotanyChinese Academy of SciencesBeijing 100093China University of Chinese Academy of Sciences Beijing 100049China University of Hong Kong Department of Ecology and Biodiversity The University of Hong Kong School of Biological SciencesChina Center for Integrative Conservation Xishuangbanna Tropical Botanical GardenChinese Academy of SciencesMenglunYunnan 666303China Minzu University of China Beijing 100081China

Myanmar is one of the most biodiverse countries in the Asia-Pacific region due to a wide range of climatic and environmental *** diversity in Myanmar is largely unknown,resulting in a lack of comprehensive conservation *** developed a database of higher plants in Myanmar derived from herbarium specimens and literature sources,and analyzed patterns of diversity inventories and collection inconsistencies,aiming to provide a baseline floristic data of Myanmar and act as a guide for future research *** collected 1,329,354 records of 16,218 *** show that the collection densities at the township level was variable,with 5% of townships having no floristic *** ecoregion had an average collection density of greater than 1 specimen/km2and the lowest collection density was found in the Kayah-Karen Montane Rainforests,which covered 8% of Myanmar’s total *** highest sampling densities were found in Mandalay Region,Chin State,and Yangon *** floristic collections over the past three centuries,knowledge of the distribution of the vast majority of plant taxa remained limited,particularly for gymnosperms,pteridophytes,and *** botanical surveys and further analyses are needed to better describe Myanmar’s floristic *** important strategy to promote knowledge of the biodiversity patterns in Myanmar is to improve the collection and digitalization of specimens and to strengthen cooperation among countries.

关键词： Biodiversity Ecoregion Higher plants Hotspots Myanmar Specimens

Bilateral iridocorneal endothelial syndrome-Chandler’s syndrome:a case report and literature review

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International Journal of Ophthalmology(English edition) 2024年第4期17卷 773-776页

作者： xiao-Hua Pan Yu-Fei Tao Ming-Min Yang xiao-li shen Jiao Si Ming li Ning Fan shenzhen Eye Hospital Jinan UniversityShenzhen 518040Guangdong ProvinceChina

Dear Editor,I ridocorneal endothelial syndrome(ICE)is a rare ocular disease first proposed by Eagle et al[1]in *** is mainly characterized by corneal endothelial abnormalities,accompanied by iris atrophy,iris pigmented nodules and peripheral anterior *** syndrome is typically unilateral,and classified into three clinical variants based on the changes of the cornea and iris,including progressive iris atrophy,Chandler’s syndrome,and Cogan-Reese syndrome.

关键词： corneal atrophy clinical

Precipitates and Hydrogen Permeation Behavior in Vanadium-Bearing Microalloyed Low Carbon Steel

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Journal of Iron and Steel Research International 2011年第S1期18卷 290-295页

作者： XU Chun,li xiao-jie,shen Da-guang (Material Engineering Department,Shanghai Institute of Technology,Shanghai 200233,China) Shanghai Inst Technol Dept Mat Engn Shanghai 200233 Peoples R China

The precipitates and hydrogen permeation behavior were studied in the low carbon steel for *** the preparation of samples,Ti containing and Ti free in vanadium-bearing microalloyed low carbon steel heating at 750℃ for 3 h,were adopted after *** was found that the a large number of fine VC,TiC,TiN and Ti 4 C 2 S 2 precipitates were in samples of Vanadium-bearing microalloyed low carbon steel with Ti *** fine VC,Fe 3 C and MnS precipitates were in steels without Ti *** the numbers of precipitates in the former is more bigger than the *** activation energies for hydrogen diffusion in both samples are 26.5 and 23.7 kJ/mol,*** at 25℃,the effective diffusion coefficients in the samples for Ti containing and Ti free in Vanadium-bearing microalloyed low carbon steel were measured as 2.71×10-6 and 4.22×10-6 cm 2 /s,*** fishscaling defect occurred in the former and heavy fishscaling defect in the later.

关键词： precipitate hydrogen permeability enameling vanadium-bearing microalloyed low carbon steel

Single-period Two-product Inventory Model with Reorder and Substitution

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Chinese Quarterly Journal of Mathematics 2006年第1期21卷 148-158页

作者： li xiao-shen GAO Ke-quan Department of Applied Mathematics Dalian University of Technology Dalian 116024 China Department of Mathematics Physics Henan University of Science Technology Luoyang 471000China

In market, excess demands for many products can be met by reorder even during one period, and retailers usually adopt substitution strategy for more benefit. Under the retailer＇s substitution strategy and permission of reorder, we develop the profits maximization model for the two-substitutable-product inventory problem with stochastic demands and proportional costs and revenues. We show that the objective function is concave and submodular, and therefore the optimal policy exists. We present the optimal conditions for order quantity and provide some properties of the optimal order quantities. Comparing our model with Netessine and Rudi＇s, we prove that reorder and adoption of the substitution strategy can raise the general profits and adjust down the general stock level.

关键词： inventory optimal order quantity substitution reorder

Generation of functionally mature neurons from a telomerase-immortalized human glial progenitor cell line

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Neural Regeneration Research 2009年第2期4卷 106-110页

作者： Yun Bai xiaoyan Zhang Aili Lu Juniun xiao li shen Department of Cell Biology School of Basic Medical Sciences Peking University Health Science Center Beijing 100191 China

BACKGROUND： It has long been thought that neurons and glial cells are produced from distinct progenitor pools, but recent studies suggest that the glial progenitor cell in the subventricular zone can generate neurons in the adult rodent brain. OBJECTIVE： To investigate the ability of a telomerase-immortalized human glial progenitor cell line to differentiate into functionally mature neurons. DESIGN, TIME AND SETTING： The cellular and molecular biology experiment was performed at the Cell Biology Laboratory in the School of Basic Medical Sciences, Peking University Health Science Center, between July 2007 and May 2008. MATERIALS： A telomerase reverse transcriptase immortalized human glial progenitor cell line, was established in our laboratory. Dibutyryl cyclic AMP was purchased from Sigma （USA）. Specific antibodies against glial fibrillary acidic protein, ~ -tubulin-Ⅲand A2B5 were purchased from Chemicon, USA. Polyclonal antibodies against nestin and MAP2ab were obtained from Neomarker, USA. METHODS： The telomerase immortalized human glial progenitor cell line was passaged and maintained in growth medium consisting of DMEM/F12 （1：1） with N2 supplement （1%, v/v）, L-Glutamine （2 mmol/L）, epidermal growth factor （20 ng/mL）, basic fibroblast growth factor （20 ng/mL） and 3% fetal bovine serum. Neuronal differentiation was induced by the addition of 1 mmol/L dibutyryl cyclic AMP and 10% fetal bovine serum. MAIN OUTCOME MEASURES： Neuronal differentiation was evaluated by RT-PCR, quantitative PCR, immunofluorescence staining, Western blot analysis and electrophysiology. RESULTS： After dibutyryl cyclic AMP induction in the telomerase immortalized human glial progenitor cells, the expression of neuronal-specific marker mRNAs and proteins increased significantly. Concurrently, an apparent fast inward Na^＋ current was evoked in the cells after induction. CONCLUSION： This study suggests that some human glial progenitor ceils are indeed capable of generating functionall

关键词： telomerase immortalization human glial progenitor cells neuronal differentiation

Obtaining and Cytological Identification of a Set of Primary Trisomics in Cabbage

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Agricultural Sciences in China 2006年第9期5卷 655-660页

作者： ZHANG Cheng-he ZHU Hai-yan li xiao-feng shen Shu-xing CHEN Xue-ping MAN Hong XUAN Shu-xin College of Horticulture Agricultural University of Hebei Baoding 071001 P.R.China

Selection of primary trisomics of the cabbage （Brassica oleracea *** L） forms an important basis for gene chromosome mapping and for other genetic studies. The cabbage self-fertilization line - 9601 was used as material, using the root-tip cell chromosome number and pollen mother cell chromosome number identification and karyotype analysis to select the primary trisomics from the progenies of 3x x 2x in the cabbage. Many aneuploid plants with one or two extra chromosomes were obtained and a set of primary trisomics （Tri-1, Tri-2, Tri-3, Tri-4, Tri-5, Tri-6, Tri-7, Tri-8, and Tri-9, in which the Tri-1 and Tri-4 were from 2n＋2 plants and others from 2n＋ 1 plants） was acquired from these plants. Each trisomic exhibited some unique features, such as plant height, plant type, leaf type, size of flower bud, and inflorescence. The triploid crossing by the diploid is a convenient and effective way to select trisomics in the cabbage.

关键词： cabbage (Brassica oleracea var.capitata L) trisomics karyotype analysis

Effect of antiallergic herbal agents on chloride channel-3 and immune microenvironment in nasal mucosal epithelia of allergic rhinitis rabbits

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Chinese Medical Journal 2010年第8期123卷 1034-1038页

作者： WANG li-feng XU li-juan GUO Feng-hua WANG li-na shen xiao-hong Medical College of Nankai University Tianjin 300071 China

Background Allergic rhinitis （AR） is a Th2 dominant cytokine response. Chloride channel-3 （CIC-3） plays an important role in nasal mucosal edema and inflammatory pathologic changes in AR. Antiallergic herbal agents （AHA） are antiallergic herbal products. In the previous study, we have demonstrated that AHA clearly inhibited allergic medium and relieved allergic reaction of AR. The aim of this study was to evaluate the function of CIC-3 and discuss the possible therapeutic effects of AHA on immune microenvironment in AR. Methods AHA were produced and used to treat AR. An animal model of an AR rabbit was established by ovalbumin （OVA）. The rhinitis rabbits were randomly divided into three groups： AHA treated group （AHATG）, model group （MG） and healthy control group （HCG）. The expressions of CIC-3 protein were examined by immunohistochemical method. The mucosal epithelial cells of all the rabbit groups were primarily cultured with tissue culture method in vitro with or without rhlL-4 or rhlL-2. Furthermore, the expressions of CIC-3 mRNA were detected by real-time PCR. The levels of monocyte chemotactic factor-1 （MCP-1） and vascular cell adhesion molecule-1 （VCAM-1） protein in culture supernatants were measured by EliSA. Results The expressions of CIC-3 mRNA increased more in mucosal epithelial cells of MG than those in AHATG and HCG （P 〈0.01）. The levels of CIC-3 mRNA, MCP-1 and VCAM-1 protein in culture supernatants of MG were significantly higher than those in the other two groups （P 〈0.01）. Those were significantly increased in MG untreated 12 hours later than those in other two groups （P 〈0.01）. The expressions of CIC-3 mRNA, MCP-1 and VCAM-1 protein in culture supernatants of MG and HCG treated with rhlL-4 were significantly higher than those in the AHATG treated with rhlL-4 （P 〈0.01）. The levels of CIC-3 mRNA, MCP-1 and VCAM-1 protein in culture supernatants of all groups treated with rhlL-2 showed no significant changes （P 〉0.05）. Conclusions AHA can inhibit the

关键词： chloride channel-3 antiallergic herbal agents allergic rhinitis immune microenvironment

Protection of MES23.5 dopaminergic cells by obestatin is mediated by proliferative rather than anti-apoptotic action

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Neuroscience Bulletin 2014年第1期30卷 118-124页

作者： xiao-li shen Feng-Ju Jia Ning Song Jun-Xia Xie Hong Jiang Department of Physiology Shandong Provincial Key Laboratory of Pathogenesis and Prevention of Neurological Disorders and State Key Disciplines: Physiology Medical College of Qingdao University

Obestatin is an endogenous peptide sharing a precursor with ghrelin. This study aims to investigate whether and how obestatin protects MES23.5 dopaminergic cells against 1-methyl-4- phenylpyridinium （MPP^＋）-induced neurotoxicity. MES23.5 cells were pretreated with obestatin （10^-13- 10^-6 mol/L） for 20 min prior to incubation with 200 μmol/L MPP^＋ for 12 or 24 h, or treated with obestatin alone （10^-13 to 10^-6 mol/L） for 0, 6, 12, and 24 h. The methyl thiazolyl tetrazolium （MTT） assay was used to measure cell viability. Flow cytometry was used to measure the caspase-3 activity and the mitochondrial transmembrane potential. Proliferating cell nuclear antigen （PCNA） protein levels were determined by Western blotting. Obestatin （10^-13 to 10^-7 mol/L） pretreatment blocked or even reversed the MPP^＋ induced reduction of viability in MES23.5 cells, but had no effect on MPP^＋-induced mitochondrial transmembrane potential collapse and caspase-3 activation. When applied alone, obestatin increased viability. Elevated PCNA levels occurred with 10^-7, 10^-9, 10^-11 and 10^-13 mol/L obestatin treatment for 12 h. The results suggest that the protective effects of obestatin against MPP^＋ in MES23.5 cells are due to its proliferation-promoting rather than anti-apoptotic effects.

关键词： obestatin MPP^+ proliferation apoptosis dopaminergic cells