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Isolation and Crystal Structure of Trans-2,2',4,4'-tetramethyl-6,6'-dinitro Azobenzene

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Chinese Journal of Structural Chemistry 2004年第9期23卷 1005-1008页

作者： wang xiao-ling YANG Bo-Lun LI Zong-xiao YUAN Chun-Lan YU Kai-Bei Environmental and Chemical Engineering Institute Xian Jiaotong UniversityXi'an 710049China Department of Chemistry and Chemical Engineering Baoji College of Arts and SciencesBaoji 721007China Chengdu Institute of Organic Chemistry The Chinese Academy of SciencesChengdu 610041China

Trans-2,2?,4,4?-tetramethyl-6,6?-dinitro azobenzene (C16H16N4O4, Mr = 328.32) was isolated from benzene extract of the leaves of Aconitum sungpanense Hand. Mazz. as a new compound, and characterized by spectral methods and X-ray diffraction analysis. It crystallizes in monoclinic system, space group P21/c with a = 8.544(1), b = 13.997(2), c = 7.161(1) ? ?= 112.97(1), V = 788.4(2) ?, Z = 4, Dc = 1.383 g/cm3, F(000) = 344 and ?MoKa) = 0.102 mm-1. The final R = 0.0395 and wR = 0.1140 for 1913 independent reflections with Rint = 0.0109 and 1329 observed reflections with I > 2s(I). The molecule is composed of two phenyl rings through trans N=N.

关键词： trans-2,2′,4,4′-tetramethyl-6,6′-dinitro azobenzene aconitum sungpanense Hand.Mazz. spectral methods X-ray diffraction analysis

Decadal Variations of Extreme Tropical Cyclones Influencing China during 1949-2009

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Advances in Climate Change Research 2012年第3期3卷 121-127页

作者： ZHAO Shan-Shan wang xiao-ling National Climate Center China Meteorological AdministrationBeijing 100081China

Decadal variations of extreme tropical cyclones （TCs） influencing China were. investigated based on the tracks, landfall information, precipitation and wind data during 1949-2009. The extreme landfall date events are less in the 1970s and 2000s. The number of extreme events of maximum wind speed and minimum pressure near TC＇s center reached the highest in the 2000s. The extreme rain duration events had the highest frequence in the 1970s, and the extreme strong wind duration events had the maximum frequence in the 1980s. The number of stations whereat the extreme maximum daily precipitation or process precipitation is observed, is the largest in the 1960s, and the number of stations whereat daily maximum wind speed events axe observed, is the largest in the 1980s.

关键词： tropical cyclone extreme events decadal variation maximum landfall intensity landfall date maximum precipitation

A new iridoid glycoside from Paederia scandens

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Chinese Chemical Letters 2010年第4期21卷 437-439页

作者： He, Da Hai Chen, Jin Song wang, xiao ling Ding, Ke Yi Southwest Univ Nationalities Ethn Pharmaceut Inst Chengdu 610041 Peoples R China

A new glycoside named 6β-O-β-D-glucosylpaederosidic acid(1) was isolated from Paederia scandens and its structure was elucidated on the basis of spectroscopic and chemical evidence,together with four known iridoids,paederoside(2),paederosidic acid(3),paederosidic acid methyl ester(4),and deacetyl asperulosidic acid methyl ester(5).Compound 5 was isolated from this plant for the first time.

关键词： Paederia scandens Iridoids Chemical structure 6β-O-β-D-Glucosylpaederosidic acid Deacetyl asperulosidic acid methyl ester

Leaf area index based nitrogen diagnosis in irrigated lowland rice

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Journal of Integrative Agriculture 2018年第1期17卷 111-121页

作者： LIU xiao-jun CAO Qiang YUAN Zhao-feng LIU Xia wang xiao-ling TIAN Yong-chao CAO Wei-xing ZHU Yan National Engineering and Technology Center for Information Agriculture Key Laboratory for Crop System Analysis and Decision Making Ministry of Agriculture/Jiangsu Key Laboratory for Information Agriculture/Jiangsu Collaborative Innovation Center forModern Crop Production/Nanjing Agricultural University Nanjing 210095 P.R. China

Leaf area index （LAI） is used for crop growth monitoring in agronomic research, and is promising to diagnose the nitrogen （N） status of crops. This study was conducted to develop appropriate LAI-based N diagnostic models in irrigated lowland rice. Four field experiments were carried out in Jiangsu Province of East China from 2009 to 2014. Different N application rates and plant densities were used to generate contrasting conditions of N availability or population densities in rice. LAI was determined by LI-3000, and estimated indirectly by LAI-2000 during vegetative growth period. Group and individual plant characters （e.g., tiller number （TN） and plant height （H）） were investigated simultaneously. Two N indicators of plant N accumulation （NA） and N nutrition index （NNI） were measured as well. A calibration equation （LAI=1.7787LAI2o00-0.8816, R2=0.870＂） was developed for LAI-2000. The linear regression analysis showed a significant relationship between NA and actual LAI （R2=0.863^＊＊）. For the NNI, the relative LAI （R2=0.808-） was a relatively unbiased variable in the regression than the LAI （R^2=0.33^＊＊）. The results were used to formulate two LAI-based N diagnostic models for irrigated lowland rice （NA=29.778LAI-5.9397; NNI=0.7705RLAI＋0.2764）. Finally, a simple LAI deterministic model was developed to estimate the actual LAI using the characters of TN and H （LAI=-0.3375（THxHx0.01）2＋3.665（TH×H×0.01）-1.8249, R2=0.875＊＊）. With these models, the N status of rice can be diagnosed conveniently in the field.

关键词： leaf area index rice LAI-2000 nitrogen diagnosis plant characters

Metabolism of Reactive Oxygen Species in the Cytoplasmic Male-Sterile Cotton Anther

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Agricultural Sciences in China 2007年第3期6卷 275-280页

作者： JIANG Pei-dong ZHU Yun-guo wang xiao-ling ZHU Wei ZHANG xiao-quan XIE Hai-yan wang Xue-de Department of Agronomy College of Agriculture ＆ Biotechnology Zhejiang University Hangzhou 310029 P.R.China College of Life Science ＆ Technology Tongji University Shanghai 200092 P.R.China

Reactive oxygen species （ROS） in plant cell, including superoxide （O2^-）, hydrogen peroxide （H2O2）, and malondialdehyde （MDA）, are thought to be important inducible factors of cell apoptosis if excessively accumulated in cells. To elucidate the metabolic mechanism of ROS production and scavenging in anthers of the cytoplasmic male-sterile （CMS） cotton, CMS line, maintainer, and hybrid F1 anthers, were employed for studying the relationship between CMS and metabolism of ROS, by comparing ROS changes in the sterile and fertile anthers at different developmental stages. The results showed that during the abortion preliminary stage （sporogenous cell division stage）, anthers of CMS line had higher contents of O2^-, H2O2, and MDA than those of maintainer or hybrid F1. Simultaneously, the higher activities of superoxide dismutase （SOD）, catalase （CAT）, and peroxidase （POD） in scavenging ROS were measured in the anthers of the CMS line, indicating that an increase of ROS in anthers of abortion preliminary stage had an inducible effect on the antioxidant enzymes. But during the abortion peak of CMS anther （pollen mother cell meiosis stage）, on the one hand, contents of O2^-, H2O2, and MDA were extraordinarily high in CMS anthers, on the other hand, the activities of SOD, CAT, and POD were excessively low, which disrupted the balance between the production and elimination of ROS and led to pollen mother cells apoptosis at this stage. In the following two stages （uninucleate microspore stage and mature pollen stage）, the contents of O2^- and H2O2 in the aborted anthers were approximated to contents in the fertile anthers of the maintainer and hybrid F1. However, MDA contents were continuously raised and enzymic activities of SOD, CAT, and POD were consistently decreased in sterile anthers, which indicated that ROS still had harmful effects on the anthers after the apoptosis of the male cells. Excessive accumulation of O2^-, H2O2, and MDA and significant reduction of ROS scaven

关键词： cotton cytoplasmic male sterility reactive oxygen species

Comparative Study on Differences of America-China Eco-Literature Viewpoints From the Perspective of Academic Compatibility

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Journal of Literature and Art Studies 2012年第8期2卷 769-778页

作者： wang xiao-ling Anhui University Anhui China

Facing the broad ＂eco-literature＂ subjects, this paper, first of all, taking eco-literature viewpoint and the theoretical connotation of eco-criticism viewpoint itself as the starting point, conducts a contrast study from the cultural origin-tracing on the American eco-literature viewpoint under the Western Bible vision and the Chinese natural eco-literature viewpoint of＂Oneness of Men and Nature＂ through the parallel comparison method; then from the visual angle of influential research is to further explore the academic compatibility in academic research： namely, the Western ecological literature consciousness begins to appear under the premise of the Western ecological civilization being destroyed, while the China＇s natural eco-literature of＂Oneness of Man and Nature＂ is based on a kind of unconscious affinity between people and nature in primitive age. Here it is necessary for us to point out that they cannot be mentioned in the same breath, because the modern ecological criticism is not the reduction of an ancient ecological thought, and also will lead to the academic non-compatibility in academic research. So only by correcting the people＇s misunderstanding in cognition, can we reach the unity of the natural ecological viewpoint and man civilized viewpoint so as to keep the harmony between human beings and nature.

关键词： eco-literature viewpoints dualism opposite thinking mode "Oneness of Men and Nature" non-compatibility harmony

Evolving Objects for Software Engineering

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Wuhan University Journal of Natural Sciences 2001年第Z1期6卷 263-267页

作者： wang xiao\|ling, Dong yi\|sheng Department of Computer Science and Engineering Southeast university, Nanjing 210018,China Department of Computer Science and Engineering Southeast university Nanjing 210018 China

This paper is concerned with evolving objects method for software design that can adapt to the changing environments and requirements automatically. We present system architecture with objects library, where there are objects based on domain ontologies. We define some genetic operators for objects, and discuss how to apply these genetic operators on objects to get new objects, which can satisfy new requirements.

关键词： object oriented ontology evolving objects meta object genetic operator mutation operator crossover operator

Principal Chemical Properties of Artificial Soil Composed of Fly Ash and Furfural Residue

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Pedosphere 2006年第5期16卷 668-672页

作者： FENG Yong-Jun LI Fen wang xiao-ling LIU Xi-Min ZHANG Lei-Na College of Resources and Environment Shandong Agricultural University Tai＇an 271018 （China） Institute of Geographical Sciences and Nature Resources Research Beijing 100101 （China）

To solve soil shortage in reclaiming subsided land of coal mines, the principal chemical properties of artificial soil formed by mixing organic furfural residue and inorganic fly ash were examined. The results indicated that the artificial soil was suitable for agriculture use after irrigation and desalination, the available nutrients in the artificial soil could satisfy the growth demand of plants, and the pH tended to the neutrality.

关键词： artificial soil chemical properties fly ash furfural residue

Prediction of Toxicity of Phenols and Anilines to Algae by Quantitative Structure-activity Relationship

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Biomedical and Environmental Sciences 2008年第3期21卷 193-196页

作者： GUANG-HUA LU CHAO wang xiao-ling GUO State Key Laboratory for Hydrology-water Resources and Hydraulic Engineering College of Environmental Science and Engineering Hohai University Nanjing 210098 Jiangsu China

Objective To measure the toxicity of phenol, aniline, and their derivatives to algae and to assess, model, and predict the toxicity using quantitative structure-activity relationship （QSAR） method. Methods Oxygen production was used as the response endpoint for assessing the toxic effects of chemicals on algal photosynthesis. The energy of the lowest unoccupied molecular orbital （ELUMO） and the energy of the highest occupied molecular orbital （EHOMO） were obtained from the ChemOffice 2004 program using the quantum chemical method MOPAC, and the frontier orbital energy gap （△E） was obtained. Results The compounds exhibited a reasonably wide range of algal toxicity. The most toxic compound was α-naphthol, whereas the least toxic one was aniline. A two-descriptor model was derived from the algal toxicity and structural parameters： logl/EC50=0.2681ogKow-1.006△E＋11.769 （n=20, r^2=0.946）. This model was stable and satisfactory for predicting toxicity. Conclusion Phenol, aniline, and their derivatives are polar narcotics. Their toxicity is greater than estimated by hydrophobicity only, and addition of the frontier orbital energy gap AE can significantly improve the prediction of logKow-dependent models.

关键词： Toxicity QSARs Frontier orbital energy gap Prediction