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Facile Syntheses of New Pyrazolo[1,5-a]pyrimidines Derivatives via Reactions of Enaminones with Aminopyrazole

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Chemical Research in Chinese Universities 2005年第6期21卷 663-667页

作者： LI Ming wang shu-wen wen Li-rong KE Zi-qin College of Chemistry and Molecular Engineering Qingdao University of Science and Technology Qingdao 266042 P. R. China Department of Chemistry Xinjiang Normal University Urumuqi 830054 P. R. China

Ethyl 7-aryl-2-benzyhhiopyrazolo [ 1,5-a ] pyrimidine-3-carboxylates （3a-3f） were conveniently synthesized through the reactions of enaminones with 5-amino-3-benzyhhio4-ethoxycarbonyl-1 H-pyrazole in good yields and high regioselectivity. The structures of the new compounds were fully characterized by spectroscopic measurmehts, elemental analysis and X-ray diffraction analysis. A plausible reaction mechanism for the formation of the title compounds was also presented.

关键词： Pyrazolo [ 1,5-a ] pyrimidine Enaminone Synthesis Mechanism Crystal structure

Five Coniferyl Alcohol Derivatives from Ligularia Duciformis

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Chemical Research in Chinese Universities 1997年第4期13卷 102-105页

作者： GAO Kun JIA Zhong-jian wang wen-shu Institute of Organic Chemistry State Laboratory of Applied Organic ChemistryLanzhou UniversityLanzhou730000

ＦｉｖｅＣｏｎｉｆｅｒｙｌＡｌｃｏｈｏｌＤｅｒｉｖａｔｉｖｅｓｆｒｏｍＬｉｇｕｌａｒｉａＤｕｃｉｆｏｒｍｉｓ＊ＧＡＯＫｕｎ，ＪＩＡＺｈｏｎｇ－ｊｉａｎ＊＊ａｎｄＷＡＮＧＷｅｎ－ｓｈｕ（ＩｎｓｔｉｔｕｔｅｏｆＯｒｇａｎ... 详细信息

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关键词： Ligularia Coniferyl Derivatives Duciformis Alcohol

EFFECTS OF CONSOLIDATION TIME AND PARTICLE SIZE ON SCOUR RATES OF COHESIVE SEDIMENT

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Journal of Hydrodynamics 2007年第2期19卷 160-164页

作者： TAN Guang-ming wang Jun shu Cai-wen LAI Yong-hui State Key Laboratory of Water Resources and Hydropower Engineering Science Wuhan University Wuhan 430072 China

By means of flumes, experiments have been done in order to determine the effects of consolidation time and particle size on scour rates of cohesive sediment. Experimental results shown dry unit weight increased and scour rates decreased during the course of consolidation, the resistance to scour was related to consolidation time, but it presented different consolidation properties that depended on particle size. For the finer particle, the consolidation process was longer, the range of dry unit weight altered was greater, the consolidated sediments moved in chunks. On the other hand, based on analysis of the relationship of dry unit weight change with consolidation time, the simplified analytical expressions of dry unit weight and scour rates were derived, the results were checked with experimental data in the same flow situation and good agreements were achieved. Since the effects of different particle size were considered during the process of consolidation, the variations of consolidation properties were well reflected in these formulas.

关键词： cohesive sediment scour rates,consolidation time dry unit weight

FINITE　TRAVELING　WAVES　FOR　A　REACTION-DIFFUSION　SYSTEM　WITH　N(≥3)COMPONENTS

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Applied Mathematics:A Journal of Chinese Universities 1997年第2期 3-14页

作者： wang shu, wen SHIHLIANG AND YE QIXIAO

ＦＩＮＩＴＥＴＲＡＶＥＬＩＮＧＷＡＶＥＳＦＯＲＡＲＥＡＣＴＩＯＮ┐ＤＩＦＦＵＳＩＯＮＳＹＳＴＥＭＷＩＴＨＮ（３）ＣＯＭＰＯＮＥＮＴＳＷＡＮＧＳＨＵ，ＷＥＮＳＨＩＨＬＩＡＮＧＡＮＤＹＥＱＩＸＩＡＯＡｂｓｔｒａｃｔ．...

ＦＩＮＩＴＥＴＲＡＶＥＬＩＮＧＷＡＶＥＳＦＯＲＡＲＥＡＣＴＩＯＮ┐ＤＩＦＦＵＳＩＯＮＳＹＳＴＥＭＷＩＴＨＮ（３）ＣＯＭＰＯＮＥＮＴＳＷＡＮＧＳＨＵ，ＷＥＮＳＨＩＨＬＩＡＮＧＡＮＤＹＥＱＩＸＩＡＯＡｂｓｔｒａｃｔ．Ｉｎｔｈｉｓｐａｐｅｒ，ｔｈｅｅｘ...

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Effects of priming treatments on germination and biochemical characteristics of Pinus bungeana seeds

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Forestry Studies in China 2012年第3期14卷 200-204页

作者： GUO Su-juan wang Yong-chao wang wen-shu Key Laboratory for Silviculture and Conservation of the Ministry of Education Beijing Forestry UniversityBeijing 100083P.R.China

This experiment was conducted to evaluate the effect of seed priming on the germination and physiology of Pinus bungeana seeds. Seeds were treated by hydropriming with distilled water, halopriming with potassium nitrate （KNO3） at -0.3, -0.6, -1.2 MPa respectively （untreated dry seeds were taken as control）. Properties of seed germination and physiology were determined and the effect of hydro- and halopriming on germination and physiology ofP. bungeana seeds were investigated. The results showed that, compared with control, each priming treatment had increased the germination percentage （GP） and germination index （GI）, shortened the mean germination time （MGT） and the time required for 50% of the seeds to germinate （Gs0）. Primed P. bungeana seeds significantly decreased the relative conductivity and the amount of malondialdehyde （MDA）. Of all the treatments applied to seeds of P. bungeana, halopriming at -0.3 MPa KNO3 produced the highest GP （65.0%） and the shortest MGT （l 8.8 d） and Gs0 （18.2 d）.

关键词： Pinus bungeana priming germination MDA

Over-Expression of Bn MAPK1 in Brassica napus Enhances Tolerance to Drought Stress

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Journal of Integrative Agriculture 2014年第11期13卷 2407-2415页

作者： wenG Chang-mei LU Jun-xing WAN Hua-fang wang shu-wen wang Zhen LU Kun LIANG Ying College of Agronomy and Biotechnology Southwest University Chongqing Rapeseed Engineering & Technology Research Center Engineering Research Center of South Upland Agriculture Ministry of Education

Mitogen-activated protein kinases （MAPKs） are a family of Ser/Thr protein kinases widely conserved in all eukaryotes and involved in responses to biotic and abiotic stresses. In this study, two over-expressing BnMAPK1 oilseed rape lines, ov3 and ov11, were used to study the drought-resistant mechanism of BnMAPK1 under natural drought and simulation drought through spraying 10%PEG 8000 in seedlings. Zhongyou 821 （WT） was used as control. Compared with wild type, transgenic seedlings had higher leaf water content, higher root activity, slightly higher peroxidase （POD） and superoxide dismutase （SOD） activity, higher proline content and lower malondialdehyde （MDA） content. The expression of drought-resistant related genes, including P5CSB, PLC, LEA4 and SCE1, have been up-regulated in some degree and the expressed time of transgenic lines were earlier than that of wild type. These results suggested that over-expression of BnMAPK1 can enhance the resistance to drought in oilseed rape （Brassica napus）.

关键词： MAPK Brassica napus transgenic drought-stress qRT-PCR

食品中氯芬新残留检测技术及风险评估研究进展

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中国兽药杂志 2024年第1期58卷 75-86页

作者：王继耀李兆新邢丽红孙晓杰王淑文李淑勤农业农村部水产品质量安全检测与评价重点实验室中国水产科学研究院黄海水产研究所山东青岛266071 青岛科技大学海洋科学与生物工程学院山东青岛266042

氯芬新在农业种植过程中的广泛使用,可能造成食品中氯芬新农药残留的问题。我国制定的氯芬新残留的限量标准主要集中在水果蔬菜等植物源性食品中,对于动物源性食品则尚未制定。目前氯芬新残留检测的前处理技术主要是采用基于固相吸附的... 详细信息

氯芬新在农业种植过程中的广泛使用,可能造成食品中氯芬新农药残留的问题。我国制定的氯芬新残留的限量标准主要集中在水果蔬菜等植物源性食品中,对于动物源性食品则尚未制定。目前氯芬新残留检测的前处理技术主要是采用基于固相吸附的萃取方法,氯芬新残留的检测技术则以液相色谱法和液相色谱-串联质谱法为主。有关氯芬新残留在食品中的风险评估还比较少,主要集中在蔬菜水果等植物源性食品中,评估结果均表明其残留不会对人体造成危害。本文针对氯芬新残留检测的前处理方法、检测方法以及风险评估作相关综述,并对其检测方法提出展望,以期为后续食品中氯芬新残留的研究提供技术支持和文献参考。

关键词：氯芬新检测技术最大残留限量风险评估

Removal of Fulvic Acids from Aqueous Solutions via Surfactant Modified Zeolite

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Chemical Research in Chinese Universities 2006年第5期22卷 566-570页

作者： wang shu-guang GONG wen-xin LIU Xian-wei GAO Bao-yu YUE Qin-yan ZHANG Dong-hua School of Environmental Science and Engineering Shandong University Jinan 250100 P. R. China

A surfactant modified zeolite（ SMZ）, i. e. , a zeolite modified by using hexadecyl trimethyl ammonium bromide （HDTMA） was used to remove fulvic acids（FA） from aqueous solution. The effects of the relevant parameters, such as the loading level of HDTMA, the contact time, the initial FA concentration, the pH, and the types of the metal carious and organics were examined. The results show that SMZ with an HDTMA loading-level of 120% of the external cation exchange capacity（ECEC） of zeolite exhibits the best performance. Although the removal of fulvic acids by SMZ occurs rapidly within the first 30 min of the contact time, a contact time of at least 4 h is required to attain the adsorption equilibrium. The removal capacity of FA by SMZ decreases with the increase of the initial FA concentration. The pH has an effect on the FA removal efficiency because it can influence the characteristics of the FA molecules. The removal of FA is considerably enhanced by Ca^2＋ or Mg^2＋ ions and is adversely affected by phenol or pentachlorophenol（PCP）. Under the optimum conditions, 98% of FA could be removed by SMZ. Furthermore, the desorption of FA and the regeneration of SMZ were studied. The results show that a 30% ethanol solution is sufficient for the regeneration of SMZ.

关键词： Surfactant modified zeolite(SMZ) Fulvic acids(FA) removal Adsorption Desorption

A Comparative Study on the Post-Buckling Behavior of Reinforced Thermoplastic Pipes(RTPs)Under External Pressure Considering Progressive Failure

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China Ocean Engineering 2024年第2期38卷 233-246页

作者： DING Xin-dong wang shu-qing LIU wen-cheng YE Xiao-han College of Engineering Ocean University of ChinaQingdao 266100China Shandong Provincial Key Laboratory of Ocean Engineering Ocean University of ChinaQingdao 266100China Department of Marine Technology Norwegian University of Science and Technology(NTNU)Trondheim NO-7491Norway

The collapse pressure is a key parameter when RTPs are applied in harsh deep-water *** investigate the collapse of RTPs,numerical simulations and hydrostatic pressure tests are *** the numerical simulations,the eigenvalue analysis and Riks analysis are combined,in which the Hashin failure criterion and fracture energy stiffness degradation model are used to simulate the progressive failure of composites,and the“infinite”boundary conditions are applied to eliminate the boundary *** for the hydrostatic pressure tests,RTP specimens were placed in a hydrostatic chamber after filled with *** has been observed that the cross-section of the middle part collapses when it reaches the maximum *** collapse pressure obtained from the numerical simulations agrees well with that in the ***,the applicability of NASA SP-8007 formula on the collapse pressure prediction was also *** has a relatively greater difference because of the ignorance of the progressive failure of *** the parametric study,it is found that RTPs have much higher first-ply-failure pressure when the winding angles are between 50°and 70°.Besides,the effect of debonding and initial ovality,and the contribution of the liner and coating are also discussed.

关键词： reinforced thermoplastic pipes post-buckling behavior progressive failure of composites debonding initial ovality