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Real-time Detection of Airborne Influenza A Viruses Using Silicon Nanowire Field Effect Transistor

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Real-time Detection of Airborne Influenza A Viruses Using Si...

利用场发射显微镜研究O_2对单壁碳纳米管场发射的影响

第七届亚洲气溶胶会议

作者： Fangxia Shen1 Miaomiao Tan1 Zhenxing Wang2 Maosheng Yao1 * Zhenqiang Xu1 Yan Wu1 Jindong Wang2 Xuefeng Guo2 * and Tong Zhu1 1 State Key Joint Laboratory for Environmental Simulation and Pollution Control college of Environmental Sciences and engineering Peking University Beijing 100871 china 2 college of chemistry and molecular engineering Peking University Beijing 100871 china

Numerous threats from biological aerosol exposures, such as H1N1 influenza, SARS, bird flu, and bio-terrorism necessitate the development of a real-time bioaerosol sensing system, which however is a long standing challenge in the field. Here, we reported real-time detection of airborne influenza H3N2 viruses by integrating electrically addressable silicon nanowire （SiNW） sensor devices with microfluidics and a bioaerosol-to-hydrosol air sampling system. Influenza A viruses were aerosolized into exposure chamber, and collected by an automated electrostatic sampler （AES） at a sampling flow rate of 5 L/min and transported onto the SiNW sensor device via microfludic channel via a peristaltic pump at a flow rate of 0.4 L/min in a real-time manner. The electrical conductance of the SiNW device was monitored using a pre-amplifier and a lock-in amplifier. Results show that when airborne influenza H3N2 virus samples were collected and delivered to antibody-modified SiNW devices, discrete nanowire conductance changes were observed within seconds. However, the conductance levels remained relatively unchanged when indoor air or clean air samples were delivered. Quantitative polymerase chain reaction （qPCR） tests indicated that higher virus concentrations in the air samples corresponded to higher conductance levels in the SiNW devices. The sensing system here has been demonstrated to have the capability to monitor the airborne presence of influenza A viruses in a real-time manner, typically from 1 to 2 minutes. This response time scale exceeds many of those available bioaerosol sensing systems. The work here opens a new arena for real-time monitoring of biological aerosols by integrating the technologies in different disciplines, holding great promise in the combat of fighting both infectious diseases and bio-terrorism.

关键词： Influenza A H3N2 virus bioaerosol Silicon Nanowire aerosol-to-hydrosol qPCR real-time detection

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物理学报 2003年第5期52卷 1282-1286页

作者：张兆祥张耿民侯士敏张浩顾镇南刘惟敏赵兴钰薛增泉北京大学电子学系北京100871 北京大学化学与分子工程学院北京100871

利用场发射显微镜和四极质谱计研究了充入高纯O2 的四极质谱和O2 对单壁碳纳米管场发射的影响 .单壁碳纳米管经过约 10 0 0℃的热处理得到清洁态场发射像后 ,充入O2 ,分别测量了O2 吸附和脱附后场发射的I V特性 .实验观测到在单壁碳纳... 详细信息

利用场发射显微镜和四极质谱计研究了充入高纯O2 的四极质谱和O2 对单壁碳纳米管场发射的影响 .单壁碳纳米管经过约 10 0 0℃的热处理得到清洁态场发射像后 ,充入O2 ,分别测量了O2 吸附和脱附后场发射的I V特性 .实验观测到在单壁碳纳米管上O2 的吸附使场发射电流减小 ,说明逸出功增加 .在 10 - 4 Pa的O2 压强下对单壁碳纳米管进行约 10 0 0℃的热处理 ,可以产生氧化刻蚀作用 ,观测到场发射像的变化 ,并测量了氧化刻蚀产生的I

关键词：场发射显微镜 O2 单壁碳纳米管氧气场发射特性四极质谱

Inhibitory effect of picroside Ⅱ on hepatocyte apoptosis

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Acta Pharmacologica Sinica 2005年第6期26卷 729-736页

作者： Hua GAO, Ya-wei ZHOU~2 college of chemistry and molecular engineering, Peking University, Beijing 100871, china college of chemistry and molecular engineering Peking University Beijing China

Aim: To investigate the influence of picroside on hepatocyte apoptosis and its mechanism. Methods: Morphological changes and quantification of apoptotic cells were determined under transmission electron microscopy and flow cytometry respectively. DNA fragmentation was visualized by agarose gel electrophoresis. Semi-quantitative reverse transcription-PCR (RT-PCR) was used to analyze the expression of bcl-2 and bax genes. The content of manganese-superoxide dismutase (SOD) in liver mitochondria was detected by the Marland method. The content of malonic aldehyde (MDA) and the protein level in liver tissue were determined by thiobarbituric acid colorimetry and Lowry method. Results: Picroside decreased the levels of alanine aminotransferase and aspartate aminotransferase in the serum resulting from acute-liver injured mice induced with D-GalN and LPS; it also reduced the content of MDA, and thus, enhanced the activity of SOD. Picroside 0 mg/kg was found to protect hepatocytes against apoptosis in a dose-dependent manner; it up-regulated the expression of bcl-2 genes, thus increased the bcl-2/bax ratio. Conclusion: Picroside 鈪an protect hepatocytes against injury and prevent hepatocytes from apoptosis. It might by upregulating the bcl-2 gene expression and antioxidation.

关键词： picroside Ⅱ hepatocytes apoptosis oxidative stress bcl-2 genes bax genes

Synthesis and Crystal Structure of 4,6Di-tert-butyl-2-hydroxy-3-(N-1-phenylethyliminomethyl) phenyl bis(triphenylphosphine)palladium bromide

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Chinese Journal of Structural chemistry 1999年第4期18卷 54-59页

作者： XU JiaXi\ ZHANG ZeYing\= (college of chemistry and molecular engineering, Peking University, Beijing 100871, china) Coll. of Chem. and Molec. Eng. Peking University Beijing 100871 China

１ＩＮＴＲＯＤＵＣＴＩＯＮＰａｌａｄｉｕｍｃｏｍｐｌｅｘｅｓｓｕｃｈａｓｔｅｔｒａｋｉｓ（ｔｒｉｐｈｅｎｙｌｐｈｏｓｐｈｉｎｅ）ｐａｌａｄｉｕｍａｒｅａｋｉｎｄｏｆｉｍｐｏｒｔａｎｔｃａｔａｌｙｓｔｓｉｎｔｈｅｒｅａ... 详细信息

１ＩＮＴＲＯＤＵＣＴＩＯＮＰａｌａｄｉｕｍｃｏｍｐｌｅｘｅｓｓｕｃｈａｓｔｅｔｒａｋｉｓ（ｔｒｉｐｈｅｎｙｌｐｈｏｓｐｈｉｎｅ）ｐａｌａｄｉｕｍａｒｅａｋｉｎｄｏｆｉｍｐｏｒｔａｎｔｃａｔａｌｙｓｔｓｉｎｔｈｅｒｅａｃｔｉｏｎｏｆｃａｒｂｏｎｃａｒ...

关键词： palladium complex synthesis molecular structure crystal structure

STABILITY OF POLY(N,N'-METHYLENEBISACRYLAMIDE-co-4-VINYLPYRIDINE)MICROGEL DISPERSION AND ADJUSTMENT OF THE HYDROPHOBICITY IN THE MICROGELS

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Chinese Journal of Polymer Science 2005年第6期23卷 635-642页

作者： Qing-de Chen Xing-hai Shen and Hong-cheng Gao Department of Applied chemistry,college of chemistry and molecular engineering,Peking University,Beijing 100871,china Department of Applied chemistry College of Chemistry and Molecular Engineering Peking University Beijing 100871 China

In the UV-Vis spectra of pure light-scattering systems, there is an exponential relationship between absorbance and wavelength （A = Kλ^-n）. Here, the exponent n is named as flocculation-coagulation parameter. In the present paper, the effects of different additives on the stability of poly（N,N＇-methylenebisacrylamide-co-4-vinylpyridine）（poly（Bis-co-4-VP）） microgel dispersion were studied in detail via this parameter. The results showed that the stability of the dispersion mainly comes from the ionization of pyridine groups, making the microgel positively charged on its surface. This was confirmed by the measurement of Zeta potential and the result of conductometric titration. The result of fluorescence analysis indicated that the hydrophobicity in the microgels is enhanced with the increase in total 4-VP unit content.

关键词： Microgel dispersion(s) 4-Vinylpyridine Flocculation-coagulation parameter Zeta potential

A thin-layer spectroelectrochemical study of 3,3',5,5'-tetramethylbenzidine at SnO_2:F film optically transparent electrode

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Science china chemistry 2004年第4期47卷 267-275页

作者： JIAO Kui1, YANG Tao2 & NIU Shuyan1,2 1. college of chemistry and molecular engineering, Qingdao University of Science and Technology, Qingdao 266042, china 2. college of chemistry and Chemical engineering, Ocean University of china, Qingdao 266003, china Correspondence should be addressed to Jiao Kui college of chemistry and molecular engineering Qingdao University of Science and Technology Qingdao China college of chemistry and Chemical engineering Ocean University of China Qingdao China

The electrooxidation of 3,3′,5,5′-tetramethylbenzidine (TMB) is dependent on the pH value of Britton-Robinson (B-R) buffer solution. In this work, the electrooxidation behavior of TMB was investigated with a SnO2:F film optically transparent thin-layer spectroelectrochemical cell. TMB underwent one two-electron electrooxidation process in the pH range from 2.0 to < 4.0, and two successive one-electron electrooxidation processes in the pH range from 4.0 to < 7.0 in the B-R buffer solution. At pH 6.5, the electrooxidative product of TMB generated a subsequent chemical reaction to yield an azo compound. Several spectroelectrochemical techniques, such as thin-layer cyclic voltammetry, thin-layer cyclic voltabsorptometry, thin-layer potential-controlled electrolysis absorptometry, thin-layer single-potential-step chronoabsorptometry, thin-layer dou-ble-potential-step chronoabsorptometry, thin-layer single-potential-step open-circuit relaxation chronoabsorptometry, were applied to this investigation. The formal potential E0’ and the electron transfer number corresponding to the electrooxidation of TMB in B-R buffer solution, and the reaction rate constant of the subsequent chemical reaction were determined.

关键词： 3,3′,5,5′-tetramethylbenzidine tin oxide film optically transparent electrode thin-layer spectroelectro-chemistry electrooxidation

EFFECTS OF L-PHENYLALANINE ON THE RADIATION SYNTHESIS OF POLY(N,N'-METHYLENEBISACRYLAMIDE-co-4-VINYLPYRIDINE)(MICRO)GELS

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Chinese Journal of Polymer Science 2005年第6期23卷 643-650页

The effects of L-phenylalanine （L-Phe） on the synthesis ofpoly（N,N＇-methylenebisacrylamide-co-4-vinylpyridine）（poly（Bis-co-4-VP））（micro）gels by γ-ray irradiation were studied. The addition of L-Phe could not only decrease the gelation dose （Dg） of the synthesis obviously, but also transform the morphology of copolymer from microgel to gel. In addition, the swelling ability of the （micro）gels was also affected in the presence of L-Phe. The decrease of Dg was ascribed to the effect of pH, while the transformation of the morphology was ascribed to the effect of L-Phe on the stability of the poly（Bis-co-4-VP） microgel. Such an effect was confirmed further as compared with the effects of L-alanine, L-glutamic acid, L-arginine, sulfuric acid and aqueous ammonia.

关键词： L-Phenylalanine γ-Ray irradiation Gelation dose Morphology transformation (Micro)gel

PROPERTIES OF POLYURETHANE ELASTOMERS BASED ON POLY (OXYETHYLENE-co-OXYTETRAMETHYLENE) DIOL

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Chinese Journal of Polymer Science 2001年第4期19卷 371-376页

作者： Chen-yu Su Guang-li Zhang Hong-zhi Zhang Department of Polymer Science and engineering college of chemistry and molecular engineering Peking University Beijing 100871, china 北京大学北京

Polyurethane elastomers derived from 4,4 ' -methylene bis(phenyl isocyanate), butylene glycol and the low oxyethylene moiety content copolyether of tetrahydrofuran and ethylene oxide, obtained by copolymerization using heteropolyacid-ethylene oxide initiator system, were prepared. The polyurethanes exhibited an increased water absorption and much better low temperature resilience, which remained high even at a temperature of -3 degreesC, while that of polyurethane based upon poly(tetramethylene ether) glycol of the 'same molecular weight, i.e. being 2000, and molecular weight distribution, i.e, in the range of 1.4-1.5, starts to decrease dramatically at 5 degreesC.

关键词： polyurethane poly(oxyethylene-co-oxytetramethylene) diol low temperature resilience heteropolyacid-ethylene oxide initiator system

Reinvestigation on the Reaction of Salicylic Chloride with Salicylic Amide and X-ray Crystal Structure of a New Macrocyclic Polyester

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Chinese Journal of Structural chemistry 2003年第5期22卷 512-516页

作者： DU Da-Ming② CHEN Xiao HUA Wen-Ting JIN Xiang-Lin (Key Laboratory of Bioorganic chemistry and molecular engineering of Ministry of Education, college of chemistry and molecular engineering, Peking University, Beijing 100871, china) college of chemistry and molecular engineering Peking University Key Laboratory of Bioorganic Chemistry and Molecular Engineering Ministry of Education 北京 100871

The reaction of salicylic chloride and salicylic amide at 170 ℃ gave benzoxazine and a new macrocyclic polyester 3, whose crystal structure has been determined by single-crystal X-ray diffraction analysis. Compound 3: C28H16O8, Mr = 480.41, monoclinic, space group P21/n, a = 15.353(3), b = 14.196(3), c = 21.147(4) ? b = 103.32(3), V = 4485(2) ?, Z = 8, F(000) = 1984, Dc = 1.423 g/cm3 and m = 0.106 mm-1. The final R = 0.0535 and wR = 0.1275 for 7903 observed reflections (I ≥ 2(I)). In the asymmetric unit of the compound there exist two independent molecules which are connected by weak aromatic CH…O hydrogen bonding between C(47)?H(47) and atom O(7) of the carbonyl group.

关键词： salicylic chloride salicylic amide polyester macrocycle crystal structure