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Synthesis and characterization of a strong-fluorescent Eu-containing hydrotalcite-like compound

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science china Chemistry 2010年第6期53卷 1273-1280页

作者： CHEN Hong & zhang WenGong Institute of Polymer science,college of Chemistry and Materials science,Fujian Normal university,Fuzhou 350007,china Institute of Polymer science College of Chemistry and Materials Science Fujian Normal University Fuzhou China

A novel strong-fluorescent Eu-containing hydrotalcite-like compound (Eu-HTlc) was synthesized using the coprecipitation method,in which aluminum(III) was partially substituted by Europium (III) in the hydrotalcite-like layers,and thenoyltrifluoroacetone,1,10-phenanthroline were dispersed into the anions in the interlayer *** sample was characterized by XRD,XPS,FT-IR,ICP,TG-DSC,TEM and fluorescence spectra,and its composition and structure were *** results indicated that the sample exhibited a characteristic red light (614 nm).The fluorescent lifetime and fluorescence quantum yield of Eu-HTlc were measured to be respectively 893 -s and 66.44%,higher than those of Eu(III)-thenoyltrifluoroacetone1,10-phenanthroline complex [Eu(TTA)3phen].The result of TG-DSC measurement showed the enhanced thermal stability of Eu-HTlc compared with that of MgAl-LDHs and Eu(TTA)*** excellent photoluminescent property and thermal stability,low contents of rare earth ions and ligands,the Eu-HTlc may become one of the novel fluorescent materials with potential applications.

关键词： hydrotalcite-like compound Europium fluorescence intercalation supramolecule

EXPERIMENTAL STUDY AND NUMERICAL SIMULATION OF FLUORIDE IN SAND

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Journal of Hydrodynamics 2006年第6期18卷 748-751页

作者： zhang Hong-mei SU Bao-yu School of Resources and Safety Engineering China University of Mining and Technology Beijing 100083China college Of Water Conservancy and Hydropower Engineering Hohai University Nanjing 210098China

The transport and transformation of fluoride in sand were studied by using soil tank test under the condition of saturated water in this article. Based on the analysis of the laboratory experiments, the rules of fluorine transportation and transformation were simulated in sand by solving the advection-diffusion equation. Through comparison between computed results and observed data , it is shown that the established model and determined parameters could be used to simulate the fluoride transport in sand.

关键词： sand fluoride dynamic test numerical simulation

Expression of the Tribolium castaneum (Coleoptera: Tenebrionidae) hsp83 gene and its relation to oogenesis during ovarian maturation

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Journal of Genetics and Genomics 2010年第8期37卷 513-522页

作者： Jingjing Xu 1, Juan Shu 1, Qin zhang Key Laboratory of Animal Genetics and Breeding of the Ministry of Agriculture, college of Animal science and Technology, china agricultural university, Beijing 100193, china Key Laboratory of Animal Genetics and Breeding of the Ministry of Agriculture College of Animal Science and Technology China Agricultural University Beijing 100193 China

Heat shock proteins （HSP） can protect organisms and cells from thermal damage. In this study, we cloned the full length cDNA encoding the HSP83 protein （the homologue of HSP90） of Tribolium castaneum（red flour beetle）. The isolated cDNA contains the full coding sequence, a partial 5＇ untranslated region of 55 bp and the complete 3＇ untranslated region. We found the hsp83 gene is located on chromosome 5 of the T. castaneum genome. The predicted HSP83 protein sequence has a high similarity （on average 86.77%） with that of other insect species. The expression of the hsp83 gene in the whole body and in the ovary could be induced with heat stress （40℃ for 1 h） in newly hatched （within 3 h post emergence） and mature （10 days post emergence） beetles. Under normal conditions, the hsp83 expression in the ovary is about 3-fold higher than in the whole body at both stages. No significant difference in hsp83 expression was observed between the two ovarian developmental stages regardless if the beetles were treated with heat shock or not. The expression of the HSP83 protein in the whole body could also be induced with heat stress in newly hatched and mature beetles. However, in the ovary, HSP83 was only expressed in the follicle cells of mature beetles and not in newly hatched beetles, regardless if the beetles were treated with heat shock or not. Furthermore, the females were not able to produce mature oocytes after knock-down of the hsp83 expression by injecting dsRNA. These results suggest that the HSP83 protein is involved in protection against heat stress and could be involved in oogenesis during ovarian maturation of T. castaneum.

关键词： hsp83 cDNA cloning Tribolium castaneum expression heat shock

Two-and Three-Dimensional Chloride Ingress into Fly Ash Concrete

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Journal of Wuhan university of Technology(Materials science) 2011年第5期26卷 978-982页

作者：张云升 Jiangsu Key Laboratory for Construction Materials Southeast University college of Materials science and Engineering Southeast University

2D,3D chloride ion concentration at the edge and corner zones were systematically investigated for fly ash concretes made with different cement replacement percentage by fly ash （0%,10%,20%,40%,60%）,water to binder ratios （0.3,0.35,0.4）,and curing ages （28 d,90 d）.An interaction effect caused by 2D and 3D diffusion could obviously be observed through the comparison with 1D testing *** order to quantify the interaction effect,2D and 3D diffusion interaction coefficients was proposed in this ***,the changes of 2D and 3D interaction coefficients with the change in the free chloride ion concentration were *** above research provide an insight into chloride ion attack on the edge and corner reinforcing bars of concrete structures in the field of civil engineering.

关键词： fly ash concrete chlorides two and three dimension ingress

NEW ROBUST UNSUPERVISED SUPPORT VECTOR MACHINES

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Journal of Systems science & Complexity 2011年第3期24卷 466-476页

作者： Kun ZHAO Mingyu zhang ~ Naiyang DENG Logistics School Beijing Wuzi University Beijing 101149 China. School of Economic and Management Beijing Jiaotong University Beijing 100044 China. college of science China Agricultural University Bcijing 100083 China.

This paper proposes robust version to unsupervised classification algorithm based on modified robust version of primal problem of standard SVMs, which directly relaxes it with label variables to a semi-definite progra... 详细信息

关键词： Robust semi-definite programming support vector machines unsupervised learning

Involvement of NADPH oxidase NtrbohD in the rapid production of H2O2 induced by ABA in cultured tobacco cell line BY-2

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Progress in Natural science:Materials International 2008年第3期18卷 267-271页

作者： Fushun Hao a,b, Jinguang zhang a, Zhonglian Yu a, Jia Chen a, a State Key Laboratory of Plant Physiology and Biochemistry, college of Biological science, china agricultural university, Beijing 100094, china b Henan Key Laboratory of Plant Stress Biology, college of Life science, Henan university, Kaifeng 475004, china State Key Laboratory of Plant Physiology and Biochemistry College of Biological Science China Agricultural University Beijing 100094 China Henan Key Laboratory of Plant Stress Biology College of Life Science Henan University Kaifeng 475004 China

The mechanisms for the production of hydrogen peroxide (H2O2) induced by abscisic acid (ABA) were investigated in suspension culture cells of tobacco BY-2 cells. The results showed that the immediate generation of H2O2, which was mainly derived from super- oxide dismutase-catalyzed dismutation of superoxide radical, was significantly induced by ABA. Furthermore, treatment of the cultured tobacco cells with ABA resulted in a time-dependent quick increase in plasma membrane (PM) NADPH oxidase activity, which coin- cided on time and magnitude with the elevation in ABA-induced accumulation of H2O2. Moreover, these enhanced effects were pro- nouncedly inhibited by two NADPH oxidase inhibitors, diphenylene iodonium and imidazole, suggesting that PM NADPH oxidase is involved in the rapid accumulation of H2O2 in cultured tobacco cells. In addition, analysis of the expression level of NtrbohD, a PM NADPH oxidase gene in tobacco, by RT-PCR and protein gel blot revealed that the gene at both mRNA and protein levels was upregulated by ABA, indicating that NtrbohD participates in the ABA-stimulated rapid production of H2O2 in tobacco culture cells. Taken together, these findings suggest that ABA induces the rapid accumulation of reactive oxygen species via NADPH oxidase in sus-pension culture cells of tobacco, and that NADPH oxidase and H2O2 appear to be important components in ABA signal transduction pathway in plants.

关键词： ABA Cultured tobacco cells H2O2 NADPH oxidase NtrbohD

A high-resolution late Pleistocene record of pollen vegetation and climate change from Jingning, NW china

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science china Earth sciences 2006年第2期49卷 154-162页

作者： LI Chunhai12, TANG Lingyu1, FENG Zhaodong3,4, zhang Hucai2, WANG Weiguo3 & AN Chenbang3 1. nanjing Institute of Geology and Palaeontology, Chinese Academy of sciences, nanjing 210008, china 2. Nanjng Institute of Geography and Limnology, Chinese Academy of sciences, nanjing 210008, china 3. Environment and Resources college, Lanzhou university, Lanzhou 730000, china 4. Beijing Normal university, Beijing 100875, china nanjing Institute of Geology and Palaeontology Chinese Academy of Sciences Nanjing China Nanjng Institute of Geography and Limnology Chinese Academy of Sciences Nanjing China Environment and Resources college Lanzhou University Lanzhou China Beijing Normal university Beijing China

With the support of 18 AMS-14C data, a high-resolution pollen record from the Suancigou section at Jingning, Gansu Province was established. Our results showed that the vegetation ex-perienced a series of changes characterized by the alternative growth and decline of forest and steppe components during the period from 44.2 to 11 ka B.P. in the Jingning area. Over the period of 44―29 ka B.P. (MIS3), coniferous forests were flourishing, indicating a humid climate with the tem-perature being lower than that of the present. Since 23 ka B.P., the vegetation was dominated by steppe-desert steppe under a cold and dry condition, and entered the Last Glacial Maximum domi-nated by desert steppe. Several periods of the marked decrease in the arborous pollen content in Suancigou well corresponded to the North Atlantic Heinrich events, especially to Heinrich event 3, further supporting that the Heinrich events were well reflected by the pollen record in the Loess Pla-teau as well.

关键词： Western Loess Plateau, pollen record, climatic change, late Pleistocene.

Chemical composition and microstructure of uroliths and urinary sediment crystals associated with the feeding of high-level cottonseed meal diet to water buffalo calves

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Chemical composition and microstructure of uroliths and urin...

Soil Fertility Indices of Citrus Orchard Land Along Topographic Gradients in the Three Gorges Area of china

中国畜牧兽医学会兽医病理学分会第十四次学术研讨会、中国病理生理学会动物病理生理专业委员会第十三次学术研讨会

作者： Xiaolong Wang, Kehe Huang, Jingbao Gao, Xiangzhen Shen, Chengyi Lin and Gengdi zhang (college of Veterinary Medicine, nanjing agricultural university, nanjing 210095, PR china Center for Materials Analysis of nanjing university, nanjing 210008, PR china Department of Earth science, nanjing university, nanjing 210008, PR china )

The chemical composition and microstructure of seven uroliths and four urinary sediment samples associated with the feeding of high-level cottonseed meal diet to buffalo calves were examined by chemical qualitative analyses, scanning electron microscopy ( ), X-ray diffraction, and X-ray energy dispersive spectrometry ( ). Struvite was a major component of kidney stones and of some bladder stones. The kidney stone sample appeared cracked under low power under, aggregated into tiny balls under high power, and as a bladelike structure under even higher power. The bladder stone samples appeared finely granular or granular with various forms of prismatic crystals. The urinary sediments were prismatic crystals, with granules. The newly found prismatic crystals, which were rich in potassium and similar to struvite in crystal structure, were identified as potassium magnesium phosphate (KMgP04·6H2O) in some bladder stones and urinary sediments. However, crystals which contained Mg and P only, which had been used for struvite identification, were not found by examination in urinary sediments from fresh urine samples of buffalo calves fed the high-level cottonseed meal diet.

关键词： Chemical composition and microstructure of uroliths and urinary sediment crystals associated with the feeding of high-level cottonseed meal diet to water buffalo calves

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Pedosphere 2011年第6期21卷 782-792页

作者： WU Dian-Ming YU Yuan-Chun XIA Li-Zhong YIN Shi-Xue YANG Lin-zhang college of Forest Resources and Environment Nanjing Forestry University Nanjing 210037 （China） State Key Laboratory of Soil and Sustainable Agriculture Institute of Soil Science Chinese Academy of Sciences Nanjing 210008 （China） college of Environmental science and Engineering Yangzhou University Yangzhou 22500g （China）

In the Three Gorges Area of china, soil erosion and the resultant non-point source pollution and ecological degradation have endangered agricultural ecosystems and fresh water reservoirs. Although efforts have been undertaken to reduce soil and water losses from slope land used for citrus production, information on the effects of management practices on soil fertility indices is either limited or nonexistent. This study was conducted to compare the effects of 10 years of various management practices, citrus intercropped with white clover (WC), citrus mulched with straw (SM), citrus intercropped with contour hedgerows (CH), citrus orchard land with impermeable membrane (IM), and citrus intercropped with wheat (Triticum aestivum) and peanut (Arachris hypogaea) (WP), as treatments on soil fertility indices with that of the conventional citrus management (CM). Results showed that the soil organic carbon, total and available nitrogen, available potassium, and water-stable aggregate (> 0.25 mm) contents at the 0–5 cm depth were higher for the WC and SM treatments than the CM treatment. There was also spatial variation in soil fertility along slopes of the WC and SM treatments. The soil total and available nitrogen, phosphorus, and potassium, and water-stable aggregate (> 0.25 mm) contents at both the 0–5 and 5–20 cm depths were higher for the CH and IM treatments than the CM treatment. The average soil available nitrogen and available potassium contents were higher for the WP treatment than the CM treatment, but the WP treatment had little effect on the soil organic carbon, total nitrogen, and water-stable aggregate (> 0.25 mm) contents. These suggested that white clover intercropping and straw mulching were the most effective approaches to improve soil fertility in citrus orchard land of the Three Gorges area.

关键词： intercropping slope land soil nutrients soil water-stable aggregates straw mulching