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Scanning Tunneling Spectroscopy of Metal Phthalocyanines on a Au(111) Surface with a Ni Tip

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Chinese Physics Letters 2011年第7期28卷 242-245页

作者： JIA Zhi-Chun HU zhen-Peng ZHAO Ai-Di li zhen-yu li Bin Hefei National Laboratory for Physical Sciences at Microscale University of Science and Technology of ChinaHefei 230026

Scanning tunneling spectroscopy of metal phthalocyanines(MPc)adsorbed on a Au(111)surface with a Ni(111)scanning tunneling microscopy tip is simulated on the basis of first-principles calculations and a modified Bardeen *** d orbital symmetry matching between the molecule and the Ni tip brings obvious negative differential resistance(NDR)phenomena,of which,bias voltage and resonant orbitals can be tuned sensitively by the central ion of the *** dependences of the NDR peak on the tip−molecule distance at two bias polarities and rectifying phenomena are also interpreted in terms of specific structures of 3d orbitals of the adsorbed MPc and Ni tip.

关键词： approximation Au(111) tunneling

Nuclear magnetic resonance based metabolomic differentiation of different Astragali Radix

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Chinese Journal of Natural Medicines 2017年第5期15卷 363-374页

作者： li Ai-Ping li zhen-yu QU Ting-li QIN Xue-Mei DU Guan-Hua Modern Research Center for Traditional Chinese Medicine Shanxi University Shanxi 030006 China College of Chemistry and Chemical Engineering Shanxi University Shanxi 030006 China School of Pharmaceutical Science Shanxi Medical University Shanxi 030006 China Institute of Materia Medica Chinese Academy of Medical Sciences Beijing 100050 China

Astragali Radix(AR) is one of the most popular herbal medicines in traditional Chinese medicine(TCM). Wild AR is believed to be of high quality, and substitution with cultivated AR is frequently encountered in the market. In the present study, two types of ARs(wild and cultivated) from Astragalus membranaceus(Fisch.) Bge. and A. membranaceus var. mongholicus(Bge.) Hsiao, growing in different regions of China, were analyzed by NMR profiling coupled with multivariate analysis. Results showed that both could be differentiated successfully and cultivation patterns or growing years might have greater impact on the metabolite compositions than the variety; the metabolites responsible for the separation were identified. In addition, three extraction methods were compared and the method(M1) was used for further analysis. In M1, the extraction solvent composed of water, methanol, and chloroform in the ratio of 1 : 1 : 2 was used to obtain the aqueous methanol(upper layer) and chloroform(lower layer) fractions, respectively, showing the best separation. The differential metabolites among different methods were also revealed. Moreover, the sucrose/glucose ratio could be used as a simple index to differentiate wild and cultivated AR. Meanwhile, the changes of correlation pattern among the differential metabolites of the two varieties were found. The work demonstrated that NMR-based non-targeted profiling approach, combined with multivariate statistical analysis, can be used as a powerful tool for differentiating AR of different cultivation types or growing years.

关键词： Nuclear Magnetic Resonance Chemical profiling Astragali Radix Cultivation patterns Variety Regions

Metabolomics coupled with similarity analysis advances the elucidation of the cold/hot properties of traditional Chinese medicines

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Chinese Journal of Natural Medicines 2017年第8期15卷 631-640页

作者： JIA Yan ZHANG zheng-zheng WEI yu-Hai Qin Xue-Mei li zhen-yu Modern Research Center for Traditional Chinese Medicine of Shanxi University Taiyuan 030006China College of Chemistry and Chemical Engineering of Shanxi University Taiyuan 030006China Qinghai Entry-Exit Inspection and Quarantine Bureau Xining 810000China

It recently becomes an important and urgent mission for modern scientific research to identify and explain the theory of traditional Chinese medicine(TCM), which has been utilized in China for more than four millennia. Since few works have been contributed to understanding the TCM theory, the mechanism of actions of drugs with cold/hot properties remains unclear. In the present study, six kinds of typical herbs with cold or hot properties were orally administered into mice, and serum and liver samples were analyzed using an untargeted nuclear magnetic resonance(NMR) based metabolomics approach coupled with similarity analysis. This approach was performed to identify and quantify changes in metabolic pathways to elucidate drug actions on the treated mice. Our results showed that those drugs with same property exerted similar effects on the metabolic alterations in mouse serum and liver samples, while drugs with different property showed different effects. The effects of herbal medicines with cold/hot properties were exerted by regulating the pathways linked to glycometabolism, lipid metabolism, amino acids metabolism and other metabolic pathways. The results elucidated the differences and similarities of drugs with cold/hot properties, providing useful information on the explanation of medicinal properties of these TCMs.

关键词： Cold/hot property Metabolomics Traditional Chinese medicine NMR Similarity analysis

Biochemical Mechanism of Chlorantraniliprole Resistance in the Diamondback Moth, Plutella xylostella linnaeus

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Journal of Integrative Agriculture 2014年第11期13卷 2452-2459页

作者： HU zhen-di FENG Xia liN Qing-sheng CHEN Huan-yu li zhen-yu YIN Fei liANG Pei GAO Xi-wu Institute of Plant Protection Guangdong Academy of Agricultural Sciences Guangdong Provincial Key Laboratory of High Technology for Plant Protection Department of Entomology China Agricultural University

The insecticide chlorantraniliprole exhibits good efifcacy and plays an important role in controlling the diamondback moth, Plutella xylostella linnaeus. However, resistance to chlorantraniliprole has been observed recently in some ifeld populations. At present study, diamondback moths with resistance to chlorantraniliprole （resistant ratio （RR） was 82.18） for biochemical assays were selected. The assays were performed to determine potential resistance mechanisms. The results showed that the selected resistant moths （GDLZ-R） and susceptible moth could be synergized by known metabolic inhibitors such as piperonyl butoxide （PBO）, triphenyl phosphate （TPP） and diethyl-maleate （DEM） at different levels （1.68-5.50-fold and 2.20-2.89-fold, respectively）, and DEM showed the maximum synergism in both strains. In enzymes assays, a high level of glutathione-S-transferase （GST） was observed in the resistant moth, in contrast, moths that are susceptible to the insecticide had only 1/3 the GST activity of the resistant moths. The analysis of short-term exposure of chlorantraniliprole on biochemical response in the resistant strain also showed that GST activity was signiifcantly elevated after exposure to a sub-lethal concentration of chlorantraniliprole （about 1/3 LC50, 12 mg L-1） 12 and 24 h, respectively. The results show that there is a strong correlation between the enzyme activity and resistance, and GST is likely the main detoxiifcation mechanism responsible for resistance to chlorantraniliprole in P. xylostella L., cytochrome P450 monooxygenase （P450） and carboxy-lesterase （CarE） are involved in to some extent.

关键词： Plutella xylostella chlorantraniliprole resistance biochemical mechanism

cDNA cloning and characterization of t he carboxylesterase pxCCE016b from the diamondback moth, Plutella xylostella L.

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Journal of Integrative Agriculture 2016年第5期15卷 1059-1068页

作者： HU zhen-di FENG Xia liN Qing-sheng CHEN Huan-yu li zhen-yu YIN Fei liANG Pei GAO Xi-wu Department of Entomology China Agricultural University Beijing 100193 P.R.China Institute of Plant Protection Guangdong Provincial Key Laboratory of High Technology for Plant Protection Guangdong Academy of Agricultural Sciences Guangzhou 510640 P.R. China

Carboxylesterase is a multifunctional superfamily and can be found in almost all living organisms. As the metabolic enzymes, carboxylesterases are involved in insecticides resistance in insects for long time. In our previous studies, the enhanced c arboxylesterase activities were found in the chlorantraniliprole resistance strain of diamondback moth（DBM）. However, t he related enzyme gene of chlorantraniliprole resistance has not been clear in this strain. Here, a full-length c DNA of carboxylesterase pxCCE016 b was cloned and exogenously expressed in Escherichia coli at the first time, which contained a 1 693 bp open reading frame（ORF） and encoded a protein of 542 amino acids. Sequence analysis showed that this c DNA has a predicted mass of 61.56 k Da and a theoretical isoelectric point value of 5.78. The sequence of deduced amino acid possessed the classical structural features： a type-B carboxylesterase signature 2（EDCLYLNVYTK）, a type-B carboxylesterase serine active site（FGGDPENITIFGESAG） and the catalytic triad（S er186, Glu316, and His444）. The real-time quantitative PCR（q PCR） analysis showed that t he expression level of the p x CCE016 b was significantly higher in the chlorantraniliprole resistant strain than in the susceptible strain. Furthermore, pxCCE016 b was highly expressed in the midgut and epidermis of the DBM larvae. When the 3rd-instar larvae of resistant DBM were exposed to abamectin, alpha-cypermethrin, chlorantraniliprole, spinosad, c hlorfenapyr and indoxacarb insecticides, the up-regulated expression of pxCCE016 b was observed only in the group treated by chlorantraniliprole. In addition, recombinant vector p ET-pxCCE016 b was constructed with the most coding region（1 293 bp） and large number of soluble recombinant proteins（less than 48 k Da） were expressed successfully with prokaryotic cell. Western blot analysis showed that it was coded by pxCCE016 b. All the above findings provide important information for further f unctional study, althou

关键词： Plutella xylostella carboxylesterase chlorantraniliprole insecticide resistance pxCCE016b

Combustion characteristics of tannery sludge and volatilization of heavy metals in combustion

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2010年第7期11卷 530-537页

作者： Xu-guang JIANG Chun-yu li zhen-wei FEI Yong CHI Jian-hua YAN State Key Laboratory of Clean Energy Utilization Zhejiang University Hangzhou 310027 China

Incineration is considered one of the most readily available techniques for sewage sludge disposal, including tannery sludge, which often contains significant amounts of volatile heavy metals. The combustion characteristics and kinetic analysis of tannery sludge were investigated using thermogravimetric analysis (TGA) at a heating rate of 30 °C/min in 50–950 °C. In addition to confirming that tannery sludge has a high content of volatile material and ash, it was further discovered that almost all the zinc (Zn) in tannery sludge is volatilized at 900 °C. The degree of volatilization for heavy metals at 900 °C followed the order of Zn>Cd>Cu>Mn>Pb>Cr. Moreover, the volatilization of these heavy metals increased with temperature. It is thus concluded that, to avoid heavy metal volatization during incineration disposal, 800 °C is a reasonable incineration temperature.

关键词： Tannery sludge Combustion Heavy metal volatilization Thermogravimetric analysis (TGA) Combustion kinetics

Fabrication and characterization of anodic oxide films on a Ti-10V-2Fe-3Al titanium alloy

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International Journal of Minerals,Metallurgy and Materials 2009年第1期16卷 96-100页

作者： Jian-hua liu Jun-lan Yi Song-mei li Mei yu Yong-zhen Xu School of Materials Science and Engineering Beihang University Beijing 100191 China

Anodic oxide films of the titanium alloy Ti-10V-2Fe-3Al in ammonium tartrate electrolyte without hydrofluoric acid or fluoride were fabricated. The morphology, components, and microstructure of the films were characterized by scanning electron microscopy （SEM）, X-ray photoelectron spectroscopy （XPS）, X-ray diffraction （XRD）, and Raman spectroscopy. The results showed that the films were thick, uniform, and nontransparent. Such films exhibited sedimentary morphology, with a thickness of about 3 μm, and the pore diameters of the deposits ranged from several hundred nanometers to 1.5 μm. The films were mainly titanium dioxide. Some coke-like deposits, which may contain or be changed by OH, NH, C-C, C-O, and C=O groups, were doped in the films. The films were mainly amorphous with a small amount of anatase and rutile phase.

关键词： titanium alloys anodic oxide films titanium dioxide pulse current method

Decoration of Electrospun Nanofibers with Magnetic Nanoparticles via Electrospinning and Sol-gel Process

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Chemical Research in Chinese Universities 2010年第5期26卷 847-850页

作者： YANG Fan zhenG Wei HUANG Hui-min li zhen-yu ZHANG Hong-nan WANG Wei WANG Ce Alan G. MacDiarmid Institute Jilin University Changchun 130012 P. R. China

Polyacrylonitrile（PAN）/Fe3O4 composite nanofibers were successfully obtained through electrospinning and sol-gel technology. The resulting magnetic Fe3O4 nanoparticles were homogeneously distributed on the surface of PAN nanofibers and the diameters of polyacrylonitrile nanofibers and nanoparticles were easily controlled, respectively. The distribution of Fe3O4 nanoparticles inside the nanofibrous composite was investigated by field emission scanning electron microscopy and transmission electron microscopy. X-ray diffraction reveals the presence of Fe3O4 nanoparticles in the composite nanofiber. The resulting sample shows a super paramagnetic behavior.

关键词： Electrospinning Magnetic Fe3O4 Nanoparticle Sol-gel

Clinical Observation on Three-character-scripture School Pediatric Tuina for Infants with Night Crying:A Report of 60 Cases

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Journal of Acupuncture and Tuina Science 2013年第1期11卷 22-25页

作者： Bi Jian-qing li yu-zhen Dai Ni-ni Ni Wen-ting Qingdao Haici Medical Group

Objective: To observe the clinical efficacy of Three-character-scripture School pediatric tuina for infants with night crying. Methods: Sixty cases with night crying were treated with Three-character- scripture School pediatric tuina, followed by observing the efficacy. Results: Forty-nine cases were recovered, 7 cases improved, and 4 cases failed. The total effective rate was 93.3%. Conclusion: Three-character-scripture School pediatric tuina is effective for night crying of infants. It should be spread and applied due to its manipulation with less acupoints, simple operation and no pain for infants.

关键词： Tuina, Massage Night Crying Infant