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Sensing characterization of Sn/In/Ti nanocomplex oxides for CO, CH_4 and NO_2

Science china(Technological Sciences) 2007年第1期50卷 18-26页

作者： BAI ShouLi1, TONG ZhangFa2, LI DianQing1, HUANG XiaoWei3, LUO RuiXian1 & CHEN AiFan1 1 State Key Laboratory of Chemical Resource engineering, beijing university of Chemical Technology, beijing 100029, china 2 School of Chemistry and Chemical engineering, Guangxi university, Nanning 530004, china 3 college of biochemical engineering, beijing union university, beijing 100023, china State Key Laboratory of Chemical Resource engineering Beijing University of Chemical Technology Beijing China School of Chemistry and Chemical engineering Guangxi University Nanning China college of biochemical engineering Beijing Union University Beijing China

The nanocomplex oxides of Sn-In and Sn-In-Ti were prepared by controlled co-precipitation method as sensing materials of semiconductor gas sensors for detection of CO, CH4 and NO2. Through manipulating the Sn/In cation ratio, metal salt total concentration, precipitation pH value and aging time, the nanocrystalline powders were successfully derived with chemical homogeneity and superior thermal stability, compared with the single component oxides. The particle size and morphology, surface area, and thermal and phase stabilities were characterized using TEM, TG-DTA, BET and XRD. The sensing tests showed that the Sn-In com-posites exhibit high sensitivity and selectivity for CO and NO2. The introduction of TiO2 enhanced CH4 sensitivity and selectivity, particularly, additives of Pd and Al2O3 as a dopant and surface modification greatly enhanced the sensing properties. The sensitivity depended on the composition of composites, calcination temperature and operating temperature. The optimal values were (25%In2O3- 75%SnO2)-20%TiO2 for ternary composite, 600 and 300℃, respectively. Temperature-programmed de-sorption (TPD) studies were employed to explain the gas adsorption behavior dis-played by the surface of nanocomposites and X-ray photoelectron spectroscopic (XPS) analysis was used to confirm the electronic interactions existing between oxide components. The sensing mechanism of the nanocomposites was attributed to chemical and electronic synergistic effects.

关键词： SnO2-In2O3-TiO2 nanocomposites CO NO2 CH4 gas sensing

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A heuristic path-estimating algorithm for large-scale real-time traffic information calculating

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Science china(Technological Sciences) 2008年第S1期51卷 165-174页

作者： L WeiFeng1,ZHU TongYu1,WU DongDong2,DAI Hong3 & HUANG Jian1 1 State Key Laboratory for Software Development Environment,Beihang university,beijing 100083,china 2 beijing Transportation Information Center,beijing 100055,china 3 college of Arts & Science,beijing union university,beijing 100083,china State Key Laboratory for Software Development Environment Beihang University Beijing China beijing Transportation Information Center Beijing China college of Arts & Science Beijing Union University Beijing China

As the original Global Position System (GPS) data in Floating Car Data have the accuracy problem,this paper proposes a heuristic path-estimating algorithm for large-scale real-time traffic information calculating. It uses the heuristic search method,imports the restriction with geometric operation,and makes comparison between the vectors composed of the vehicular GPS points and the special road network model to search the set of vehicular traveling route candidates. Finally,it chooses the most optimal one according to weight. Experimental results indicate that the algorithm has considerable efficiency in accuracy (over 92.7%) and com-putational speed (max 8000 GPS records per second) when handling the GPS tracking data whose sampling rate is larger than 1 min even under complex road network conditions.

关键词： path-estimating floating car data (FCD) road network vector GPS

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Cu(Ⅱ) Potentiation of Alzheimer Aβ1-40 Cytotoxicity and Transition on its Secondary Structure

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Acta Biochimica et Biophysica Sinica 2006年第11期38卷 765-772页

作者： Xue-Ling DAI~1 Ya-Xuan SUN~2 Zhao-Feng JIANG~2* 1 college of Life Science,Capital Normal university,beijing 100037,china 2 college of Applied Sciences and Humanities,beijing union university,beijing 100083,china college of Life Science Capital Normal UniversityBeijing 100037 China college of Applied Sciences and Humanities Beijing Union UniversityBeijing 100083 China

Mounting evidence has shown that dyshomeostasis of the redox-active biometals such as Cuand Fe can lead to oxidative stress,which plays a key role in the neuropathology of Alzheimer's disease（AD）.Here we demonstrate that with the formation of Cu（Ⅱ）·Aβ1-40 complexes,copper markedly potentiatesthe neurotoxicity exhibited by β-amyloid peptide （Aβ）.A greater amount of hydrogen peroxide was releasedwhen Cu（Ⅱ）·Aβ1-40 complexes was added to the xanthine oxidase/xanthine system detected by potassiumiodide *** bound to Aβ1-40 was observed by electron paramagnetic resonance（EPR） *** dichroism （CD） studies indicated that copper chelation could cause a structuraltransition of Aβ.The addition of copper to Aβ introduced an increase on β-sheet as well as α-helix,whichmay be responsible for the aggregation of Aβ.We hypothesized that Aβ aggregation induced by copper maybe responsible for local injury in *** interaction between Cu2+and Aβ also provides a possible mechanismfor the enrichment of metal ions in amyloid plaques in the AD brain.

关键词： Alzheimer’s disease Cu(Ⅱ)·Aβ1-40 complex neuron injury Aβ secondary structure

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2023 Guideline for the management of hypertension in the elderly population in china

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Journal of Geriatric Cardiology 2024年第6期21卷 589-630页

作者： Hypertension Branch of Chinese Geriatrics Society,beijing Hypertension Association,National Clinical Research Center of the Geriatric Diseases Qi HUA Li FAN Zeng-Wu WANG Jing LI 不详 Xuanwu Hospital Capital Medical UniversityBeijingChina Chinese PLA General Hospital BeijingChina Fuwai Hospital Chinese Academy of Medical Sciences and Peking Union Medical CollegeBeijingChina

Preamble Hypertension is one of the most common chronic diseases and the primary risk factor for stroke,myocardial infarction and even cardiovascular *** than half of the elderly population has high blood *** people are a unique group,and strategies for the prevention,diagnosis,evaluation,and treatment of hypertension in elderly individuals differ significantly from those in the general population.

关键词： hypertension prevention diagnosis

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Protective Effects of Vitamin E against Oxidative Damage Induced by Aβ(1-40)Cu(Ⅱ)Complexes

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Acta Biochimica et Biophysica Sinica 2007年第2期39卷 123-130页

作者： Xueling DAI~1 Yaxuan SUN~2 and Zhaofeng JIANG~2 ~1college of Life Science,Capital Normal university,Bejing 100037,china ~2college of Applied Sciences Humanities of beijing union university,beijing 100083,china college of Life Science Capital Normal UniversityBeijing 100037 China college of Applied Sciences and Humanities of beijing union universitybeijing 100083 China

β-amyloid peptide （Aβ） is considered to be responsible for the formation of senile plaques,which is the hallmark of Alzheimer's disease （AD）.Oxidative stress,manifested by protein oxidation andlipid peroxidation,among other alterations,is a characteristic of AD brain.A growing body of evidence hasbeen presented in support of Aβ1-40forming an oligomeric complex that binds copper at a CuZn superoxidedismutase-like binding site. Aβ1-40Cu（Ⅱ） complexes generate neurotoxic hydrogen peroxide （H2O2） from O2via Cue+ reduction,though the precise reaction mechanism is *** toxicity of Aβ1-40or the Aβ1-40Cu（Ⅱ）complexes to cultured primary cortical neurons was partially attenuated when （+）-α-tocopherol （vitamin E）as free radical antioxidant was added at a concentration of 100 μ*** data derived from lactate dehydro-genase （LDH） release and the formation of H2O2confirmed the results from the MTT *** findingsindicate that copper binding to Aβ1-40can give rise to greater production of H2O2, which leads to a break-down in the integrity of the plasma membrane and subsequent neuronal *** treated with vitaminE exhibited much slighter damage,suggesting that vitamin E plays a key role in protecting neuronal cellsfrom dysfunction or death.

关键词： Aβ1-40Cu(II)complex vitamin E neuronal oxidative damage H2O2 generation lactate dehydrogenase(LDH)release

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CONTROLLED RELEASE FROM PDMAEMA GELS PREPARED BY GAMMA RADIATION

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Chinese Journal of Polymer Science 2002年第5期20卷 409-412页

作者： Ning Liu Min Yi Shuang-ji Chen Hong-fei Ha college of Chemistry and Molecular engineering Peking university beijing 100871, china Department of Biochemistry college of Applied Arts and Science, beijing union university beijing 100083. china college of Chemistry and Molecular engineering Peking University 北京 100871 Department of Biochemistry College of Applied Arts and Science Beijing Union University 北京 100083

Poly(N,N-dimethylaminoethyl methacrylate) (polyDMAEMA) hydrogels prepared by gamma-irradiation showed obvious temperature-sensitivity in a temperature range of 38-40degreesC and pH-sensitivity at pH=2.5. They also showed electric response behavior although it was not typical. The hydrogels were used in controlled release at different pH, temperature, and electric voltage. The release rates of methylene blue (MB) from the gels at 52degreesC and pH=1.24 were faster than those at 20degreesC and pH=10.56, respectively. In addition, the release rate at a field voltage of 5.0 was also faster than that without electric field.

关键词： poly(N,N-dimethylaminoethyl methacrylate) environmental sensitivity hydrogel controlled release

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Biogas recovery from microwave heated sludge by anaerobic digestion

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Science china(Technological Sciences) 2010年第1期53卷 144-149页

作者： QIAO Wei1,WANG Wei2,ZHU CuiPing3 & ZHANG ZhongZhi1 1 college of Chemical Science and engineering,china university of Petroleum,beijing 102249,china 2 Department of Environmental Science and engineering,Tsinghua university,beijing 10084,china 3 J & K china Cleaning Energy Technology Co.Ltd.,beijing 100085,china college of Chemical Science and engineering China University of Petroleum Beijing China Department of Environmental Science and engineering Tsinghua University Beijing China J & K china Cleaning Energy Technology Co. Ltd. Beijing China

Biogas generated from sewage sludge,livestock waste,and food waste by anaerobic digestion is a valuable renewable energy ***,conventional anaerobic digestion is not an efficient process.A long hydraulic retention time and low biogas recovery rate hinder the applications of those *** effective pretreatment method to destroy sludge microbial cells has been one of the major concerns regarding improvement of the biogas *** article focuses on the effects of microwave heating on sludge anaerobic *** suspended solid(VSS) and chemical organic demand solubilization of heated sludge were *** heating was found to be a rapid and efficient process for releasing organic substrates from *** increase of organic dissolution ratio was not obvious when holding time was over 5 min with microwave *** effect of the VSS solubilization was primarily dependent on heating *** highest value of VSS dissolving ratio,36.4%,was obtained at 170°C for 30 *** COD dissolving ratio was about 25% at 170°*** organic carbon of treated sludge liquor was 1.98 and 2.73 g/L at 150°C and 170°C for 5 min,respectively.A biochemical methane potential(BMP) test of excess sludge and a mixture of primary and excess sludge demonstrated an increase in biogas *** total biogas from microwave treated mixture sludge increased by 12.9% to 20.2% over control after 30 days of *** production was 11.1% to 25.9% higher for excess sludge than for untreated *** VS removal ratios of mixture sludge and excess sludge were 12% and 11% higher,respectively,compared to the untreated sludge.

关键词： biogas recovery microwave heating sludge anaerobic digestion

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Nanocomposites Preparation and Its Application to Sensor

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稀有金属材料与工程 2006年第S3期 29-32页

作者： Dianqing Li~1 Zhangfa Tong~2 Xiaowei Huang~3 Shouli Bai~1 Ruixian Luo~1 (1.State Key Laboratory of Chemical Resource engineering,beijing university of Chemical Technology,beijing 100029,china) (2.college of Chemistry and Chemical engineering,Guangxi university,Nanning 530004,china) (3.Colloge of Biochemistry engineering,beijing union university,beijing 100023,china)

The nanocomposites of ZnO-SnO2and In2O3-SnO2were prepared by wet chemical co-precipitation method as a novel semiconductor gas sensing materials for the detection of environmentally toxic *** preparation parameters were critical towards the grain size and crystallinity of the obtained *** results showed that these nanocomposites exhibited high sensitivity and selectivity for the detection of CO and NOx,and the sensitivity depended on the composition of the composite,calcination temperature and operating *** gas sensing properties of the sensors were further improved through incorporation of dopants and surface *** gas sensing mechanism was also discussed by X-ray photoelectron spectroscopic （XPS） and temperature-programmed desorption （TPD） studies.

关键词： ZnO-SnO2 In2O3-SnO2 nanocomposites gas sensor sensing properties

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Effects of long-term,low-dose sex hormone replacement therapy on hippocampus and cognition of postmenopausal women of different apoE genotypes

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Acta Pharmacologica Sinica 2007年第8期28卷 1129-1135页

作者： Yun YUE~1 Ling HU~2 Qin-jie TIAN~2 Jing-mei JIANG~ 1 Yi-long DONG~1 Zheng-yu JIN~2 Yu-hang CHENG~3 Xia HONG~2 Qin-sheng GE~2 Ping-ping ZUO~(1,4) ~1School of Basic Medicine,Peking union Medical college and Institute of Basic Medical Seience,Chinese Academy of Medical Sciences,beijing 100005,china ~2Peking union Medical college Hospital,beijing 100730,china ~3beijing Anding Hospital,beijing 100088,china School of Basic Medicine Peking Union Medical College and Institute of Basic Medical Science Chinese Academy of Medical Sciences Beijing China Peking union Medical college Hospital Beijing China beijing Anding Hospital Beijing China

Aim:To study the effects of long-term,low-dose sex hormone replacement therapy(HRT)on the volume and biochemical changes of the hippocampus in postmeno-pausal women carrying apolipoprotein E(apoE)gene ε3 or ε***:Eighty-three postmenopausal women who had used a low dose of HRT for over 4 yearswere selected as the HRT group,and 99 postmenopausal women with matchedage and education were enrolled as the control *** alleles were analyzedby *** resonance imaging was performed to determine the volume ofthe brain *** magnetic resonance spectroscopy was used todetect the biochemical changes in the anterior cingulate cortex and hippocampusin apoE ε4 and ε3 *** common cognitive tests were used to make anoverall evaluation of cognitive ***:Analysis with the apoE ε4carriers showed that the volume of the hippocampus of the control group weresignificantly lower than those of the HRT *** biochemical analysis showedthat there was an increase of N-acetylaspartate(NAA)/total creatine(tCr)and adecrease of myoinositol(mI)/tCr in the hippocampus of apoE ε4 carriers in theHRT group,compared with the control *** the apoE ε3 carriers,the leastsquares means(LSMEAN)of the HRT group was higher than that of the ***:This study showed that long-term,low dose HRT might bebeneficial for reducing the risk of AD development in vulnerable ***,HRT could increase the LSMEAN of apoE ε3 carriers.

关键词： hormone replacement therapy apoE Alzheimer’s disease magnetic resonance imaging

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Cubic Convergence and Applications of a Variant of Newton-Method for Systems of Nonlinear Equations

Cubic Convergence and Applications of a Variant of Newton-Me...

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2011 International Conference on Mechanical, Industrial, and Manufacturing engineering (MIME 2011)

作者： Liu Zhongli college of biochemical engineering beijing union university,beijing 100023,china Zheng Quan college of Science North china university of Technology,beijing china

Numerical solutions for nonlinear equations and systems of nonlinear equations have always appealed greatly to *** method is a universally acknowledged classical *** paper probes into the third-order semilocal convergence of a variant of Newton method or Traub formula for the systems of nonlinear equations and presents the numerical examples for proving the correctness of the analysis of such convergence and confirming the efficiency and feasibility of the iterative *** is,we extend the iterative formula from one dimension to n dimensions and get its convergence ball.

关键词： systems of nonlinear equations Traub formula semilocal convergence convergence ball

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