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One-pot synthesis of network supported catalyst using supramolecular gel as template

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Chinese Chemical Letters 2010年第8期21卷 991-994页

作者： Yong liang li Ming Tang Yu Xia Kai chen Bo Tian li xin Jin Laboratory of Advanced Materials Department of Chemical EngineeringTsinghua UniversityBeijing 100084China

A simple and general strategy is described for preparing network supported catalyst through a one-pot synthetic procedure using supramolecular gel as *** procedure directly attaches ligand to support during fabricating the *** this strategy,supported CuBr/di-（2-picolyl） amine catalyst with U-shaped fibrillar network was prepared and used in atom transfer radical polymerization of methyl *** and SEM characterization of the catalyst revealed homogeneous distribution of ligand,sufficient reactive sites,adequate mechanical strength and *** polymerization results demonstrated high activity and reusability of such *** strategy might be extended to other supported catalysts used in column reactors.

关键词： One-pot synthesis Network supported catalyst Supramolecular gel Atom transfer radical polymerization

Biosensor Based on TTF@SiO_2 Nanoparticles as Electron Transfer Mediator for the Determination of Glucose

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Chemical Research in Chinese Universities 2006年第4期22卷 474-478页

作者： li Xiao-hua XIAN Yue-zhong MIN Hong li chen-xin XIE Zong-hong ZHANG Fen-fen JIN li-tong Department of Chemistry East China Normal University Shanghai 200062 P. R. China

Tetrathiafulvalene（TTF） was doped in an SiO2 network and the resulting nanocompesite was used as a mediator for the selective detection of glucose. The uniform TTF-doped silica（TIT@SiO2 ） nanoparticles were prepared by the water-in-oil（W/O） microemulsion method, and were characterized by transmission electron microscopy（TEM）. The core-shell structure TTF@ SiO2 could prevent TIT from leaching out into an aqueous solution. Combined with chitosan （CHIT）, which serves as a scaffold for glucose oxidase and nanocomposite immobilization, the GCE/TTF@ SiO2- CHIT-GOx biosensor was developed. Under optimal conditions, the biosensors exhibit a linear range of 1.0 × 10^-5 5 × 10^-3 mol/L with a detection limit down to 5.0 μmol/L（S/N = 3 ）. The excellent selectivity, sensitivity, and stability of the glucose biosensor show its potential for practical applications.

关键词： TTF@ SiO2 nanoparticle Chitosan Glucose Biosensor

Preparation and Ethanol Sensing Properties of ZnO Nanofibers

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Chemical Research in Chinese Universities 2011年第5期27卷 720-723页

作者： FENG Cai-hui RUAN Sheng-ping ZHU ling-hui li Chao li Wei chen Wei-you chen li-hua ZHANG xin-dong State Key Laboratory on Integrated Optoelectronics College of Electronic Science and Engineering Jilin University Changehun 130012 P. R. China

ZnO nanofibers with an average diameter of about 90 nm were prepared by an electrospinning method combined with a calcination process. The as-electrospun nanofibers before and after calcination were characterized by means of differential thermal analysis（DTA）, thermal gravimetric analysis（TGA）, X-ray diffraction（XRD） and scanning electron microscopy（SEM）. The fibers after calcination at 600 °C belong to the hexagonal wurtzite structure. The sensor based on ZnO nanofibers exhibited excellent ethanol sensing properties at 206 °C such as good linear dependence in the low concentration（1―100 μL/L）, high response, and good selectivity. Fast response（less than 2 s） and recovery（about 16 s） were also observed in our investigations.

关键词： Electrospinning method ZnO Nanofiber Ethanol Gas sensor

Curcumin,a Potential Inhibitor of Up-regulation of TNF-alpha and IL-6 Induced by Palmitate in 3T3-L1 Adipocytes through NF-kappaB and JNK Pathway

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Biomedical and Environmental Sciences 2009年第1期22卷 32-39页

作者： SHAO-liNG WANG YING li YING WEN YAN-FENG chen li-xin NA SONG-TAO li CHANG-HAO SUN Department of Nutrition and Food Hygiene Harbin Medical University No. 157 Baojian Road Harbin 150081 Heilongjiang China

Objective To investigate the attenuating effect of curcumin, an anti-inflammatory compound derived from dietary spice turmeric （Curcuma longa） on the pro-inflammatory insulin-resistant state in 3T3-L1 adipocytes. Methods Glucose uptake rate was determined with the [3H] 2-deoxyglucose uptake method. Expressions of tumor necrosis factor-α （TNF-α） and interleukin-6 （IL-6） were measured by quantitative RT-PCR analysis and EliSA. Nuclear transcription factor kappaB p65 （NF-r,B p65） and mitogen-activated protein kinase （MAPKs） were detected by Western blot assay. Results The basal glucose uptake was not altered, and curcumin increased the insulin-stimulated glucose uptake in 3T3-L1 cells. Curcumin suppressed the transcription and secretion of TNF-α and IL-6 induced by palmitate in a concentration-dependent manner. Palmitate induced nuclear translocation of NF-kB. The activities of Jun NH2-terminal kinase ONK）, extracellular signal-regulated kinasel/2 （ERKI/2） and p38MAPK decreased in the presence of curcumin. Moreover, pretreatment with SP600125 （inhibitor of JNK） instead of PD98059 or SB203580 （inhibitor of ERKI/2 or p38MAPK, respectively） decreased the up-regulation of TNF-α induced by palmitate. Conelusion Curcumin reverses palmitate-induced insulin resistance state in 3T3-L1 adipocytes through the NF-kB and JNK pathway.

关键词： Curcumin Insulin resistance Inflammation Adipocyte Free fatty acids

Differences of carbon and nitrogen stoichiometry between different habitats in two natural Korean pine forests in Northeast China's mountainous areas

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Journal of Mountain Science 2022年第5期19卷 1324-1335页

作者： WANG Ya-fei DUAN Wen-biao QU Mei-xue chen li-xin LAN Hang-yu YANG Xi-feng MENG Si-jing chen Jia School of Forestry Northeast Forestry UniversityHarbin 150040China

There is a strong link between vegetation and environmental ***,to elucidate how the stoichiometric characteristics of plants respond to different habitats,we studied organic carbon(C)and total nitrogen(N)stoichiometry characteristics of plants in four different habitats of two different natural Korean pine *** of the habitats(gaps,mounds,and pits)were formed via tree uprooting,whereas an undisturbed site(closed canopies)was used as a *** followings were our main findings:(1)the organic carbon content of more than half of the 12 picked plants showed significant differences in different *** of the plants in pit-mound complexes exhibited lower organic carbon contents than plants in gaps and closed canopies;(2)there was no significant differences in the total nitrogen content in 13 of the 25 groups of plant samples;(3)interestingly,the C/N of the sample groups with significant differences in total nitrogen also showed significant differences;(4)there was no significant variations in the stoichiometric characteristics of plants that grew in gaps;however,the variations among plants that grew in pits and mounds were significant;(5)through redundancy analysis(RDA),we find that the main factors effecting the C and N stoichiometric characters of the plants were plants own regulation and the change of photosynthetically active radiation(PAR).In conclusion,the C and N stoichiometric characteristics of plants did not respond to gap formations,but they did strongly respond to pit-mound complex *** active radiation was the most important effective factor to plants in the four habitats.

关键词： Uprooting Site type Carbon Nitrogen Stoichiometric characteristics

Diagnostic values of combination of free running asthma screening test and total serum allergen IgE level in children with asthma

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Chinese Medical Journal 2014年第5期127卷 873-877页

作者： chen xin li Yong Zeng Meiying Department of Senior Officials Health Care China-Japan Friendship Hospital Beijing 100029 China

Background A free running asthma screening test is usually used for screening exercise-induced *** total serum allergen IgE level can reveal the patient＇s atopy *** study is to evaluate the diagnostic values of the combination of the two tests in asthmatic children and compare this new diagnostic method with the Intemational Study of Asthma and Allergies in Childhood （ISSAC） questionnaires and the bronchial provocation test,which are popular diagnostic tool for pediatric *** A total of 773 school children were recruited in this *** children＇s asthma was diagnosed by means of a combination of the free running asthma screening test and total serum allergen IgE *** new diagnostic method value was assessed using receiver operating characteristic （ROC） curves and compared with other diagnostic tools such as ISSAC questionnaires and the bronchial provocation *** The AUC of this new diagnostic method was higher than *** the cut-off value of total serum allergen IgE level was ≥47 KU/L,the sensitivity and the specificity were 71.4％ and 85.1％,respectively,which were better than those of either the ISSAC questionnaires or bronchial provocation *** The combination of the free running asthma screening test and total serum allergen IgE level may be an effective diagnostic tool for children＇s asthma.

关键词： children asthma free running asthma screening test total serum allergen IgE level combination diagnostic value

Effects of Exogenous Cinnamic Acids on the Growth and Physiological Characteristics of Cucumber Seedlings

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Agricultural Sciences in China 2005年第10期4卷 747-751页

作者： chen li-xin WU Feng-zhi MA Feng-ming Northeast Agricultural University Harbin 150030 P.R.China Heilongjiang Academy of Agricultural Sciences Horticultual Sub-Academy Harbin 150069 P.R.China

In order to study the effects of exogenous cinnamic acids on plant growth, contents of photosynthetic pigment, root activities and ATPase activities of root membrane at cucumber seedling stage, the seedlings of Shandong Mici cucumber were tested. The results showed that seedlings growth, contents of photosynthetic pigment, root activities and ATPase activities of root membrane were inhibited by cinnamic acids. The growth and root activities of seedlings were significantly （P〈0.05） lower in the soil amended with 100 mg kg^-1 cinnamic acids compared to the control. The contents of chlorophyll a, chlorophyll a＋b and carotenoid of seedlings significantly （P〈0.05） decreased in the soil amended with 200 mg kg^-1 cinnamic acids, whereas ATPase activities exhibited a higher sensitivity and greatly decreased in the soil amended with 50 mg kg^-1 cinnamic acids. These results suggested that cinnamic acids could induce a stress condition, and the stress intensities increased with enhanced cinnamic acid concentration.

关键词： Cucumber Cinnamic acids Photosynthetic pigment Root activities ATPase

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KCT型补偿导线合金丝研究

功能材料 2011年第B6期42卷 577-580页

作者：谌立新李峰陈洁重庆仪表材料研究所重庆400700 国家仪表功能材料工程技术研究中心重庆400700

KCB补偿导线在航空发动机上作为K型热电偶排气温度传感器的连接线而大量采用，但是KCB的使用温度仅为0～100℃（其精度可为4-1．5和±3．0℃），而当发动机周围的环境温度高于150℃时补偿导线引入的误差较大，尤其温度达到300℃以上，... 详细信息

KCB补偿导线在航空发动机上作为K型热电偶排气温度传感器的连接线而大量采用，但是KCB的使用温度仅为0～100℃（其精度可为4-1．5和±3．0℃），而当发动机周围的环境温度高于150℃时补偿导线引入的误差较大，尤其温度达到300℃以上，其误差可达到18℃。研究了一种新型K型热电偶补偿导线KCT，通过对KPCT—KNCT补偿导线合金丝的生产工艺路线研究；掌握了合金配方和熔炼、拉丝、热处理等各个环节的技术关键；保证了合金丝的稳定批量生产，满足了用户需求。

关键词： K型热电偶补偿导线合金丝热电动势

Analysis of Pulse Tolerance to Pump Depletion Induced Noise in DWDM Systems Using Distributed Fiber Raman Amplifiers

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Chinese Journal of Lasers 2002年第3期11卷 60-63页

作者： YAN Minhui chen Jianping li Jianlang JINAG Wenning chen Junfeng li xin (The State Key Laboratory on Fiber Optic Local Area Communication Networks and Advanced Optical Communication Systems, Shanghai Jiao Tong University, Shanghai 200030, China) 上海交通大学 The State Key Laboratory on Fiber-Optic LocalArea Communication Networks and Advanced Optical Communication Systems 上海 200030

In distributed optical fiber Raman amplifiers, instantaneous pump power depletion is related to patterns of input DWDM signals and results in extra optical noise and crosstalk. This noise has different effects on non return to zero (NRZ) and return to zero (RZ) pulse forms. These phenomena are compared with present simulation results.

关键词： Raman scattering optical amplifiers dense wavelength division multiplexing crosstalk Optical noise