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Periodic Solutions for p-laplacian Neutral Functional Differential Equation with a Deviating Argument

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Chinese Quarterly Journal of Mathematics 2013年第4期28卷 585-591页

作者： CHEN Wen-bin ga O Fang l u Shi-ping College of Mathematics and Computer Science Anhui Normal University Wuhu 241003 China

In this paper, by using the continuation theorem of coincidence degree theory and some analysis methods, we study a kind of periodic solutions to p-laplacian neutral functional differential equation with a deviating a... 详细信息

关键词： periodic solution deviating argument coincidence degree

l-乳酸和乙醇酸共聚物的直接合成与微结构分析

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高校化学工程学报 2006年第6期20卷 951-956页

作者：兰平吕佳嘉兴学院浙江嘉兴314001

采用直接法熔融缩聚制备l-乳酸(l-lA)和乙醇酸(ga)共聚物。先是以摩尔比为90/10的l-lA和ga为原料生成低聚物,然后l-lA和ga低聚物在双催化剂二水合氯化亚锡和对甲苯磺酸的催化下进一步反应。在反应中,未使用任何有机溶剂。反应最终产物... 详细信息

采用直接法熔融缩聚制备l-乳酸(l-lA)和乙醇酸(ga)共聚物。先是以摩尔比为90/10的l-lA和ga为原料生成低聚物,然后l-lA和ga低聚物在双催化剂二水合氯化亚锡和对甲苯磺酸的催化下进一步反应。在反应中,未使用任何有机溶剂。反应最终产物的性能和结构通过核磁共振(NMR)、差示扫描量热(DSC)等手段进行表征。结果表明,ga显示了比l-lA更高的反应活性,聚合过程中可能通过酯交换减少了ga和lA嵌段长度,而且随着ga含量和反应时间的增加会使共聚物产生更多的消旋,并使结晶度下降。目前反应条件下进行了嵌段共聚而非随机共聚。结果也表明,相对分子质量较高的l-lA和ga共聚物是可以通过直接聚合在适宜的工艺条件下制得。

关键词：乳酸乙醇酸熔融缩聚直接法微结构

Saccharomyces cerevisiae prevents postoperative recurrence of Crohn's disease modeled by ileocecal resection in HlA-B27 transgenic rats

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World Journal of gastroenterology 2023年第5期29卷 851-866页

作者： Caroline Valibouze Silvia Speca Caroline Dubuquoy Florian Mourey lena M'ba lucil Schneider Marie Titecat Benoît Foligné Michaël Genin Christel Neut Philippe Zerbib Pierre Desreumaux Department of Digestive Surgery and Transplantation Lille University HospitalLille 59037France u1286-INFINITE-Institute for Translational Research in Inflammation Univ.LilleInsermCHU LilleLille 59000France Intestinal Biotech Development Lille 59045France Department of Research and Applications Gnosis by LesaffreLesaffre GroupMarcq-en-Baroeul 59700France ulR 2694-METRICS:Évaluation des Technologies de Santéet des Pratiques Médicales University of LilleLille University HospitalLille 59000France Department of Hepato-gastroenterology Lille University HospitalLille 59037France

baCKGROuND Postoperative recurrence(POR)after ileocecal resection(ICR)affects most Crohn's disease patients within 3-5 years after ***-invasive Escherichia coli(AIEC)typified by the lF82 strain are pathobionts that are frequently detected in POR of Crohn's disease and have a potential role in the early stages of the disease *** cerevisiae CNCM I-3856 is a probiotic yeast reported to inhibit AIEC adhesion to intestinal epithelial cells and to favor their elimination from the *** To evaluate the efficacy of CNCM I-3856 in preventing POR induced by lF82 in an HlA-B27 transgenic(TgB27)rat *** Sixty-four rats[strain F344,38 TgB27,26 control non-Tg(nTg)]underwent an ICR at the 12th wk(W12)of life and were sacrificed at the 18th wk(W18)of ***27 rats were challenged daily with oral administration of lF82(109 colony forming units(CFus)/day(d),n=8),PBS(n=5),CNCM I-3856(109 CFus/d,n=7)or a combination of lF82 and CNCM I-3856(n=18).nTg rats receiving lF82(n=5),PBS(n=5),CNCM I-3856(n=7)or CNCM I-3856 and lF82(n=9)under the same conditions were used as *** was analyzed using macroscopic(from 0 to 4)and histologic(from 0 to 6)*** lF82 quantifications were performed weekly for each *** lF82 and inflammatory/regulatory cytokines were quantified in biopsies at W12 and *** are expressed as the median with the interquartile *** nTg animals did not develop POR.A total of 7/8(87%)of the TgB27 rats receiving lF82 alone had POR(macroscopic score≥2),which was significantly prevented by CNCM I-3856 administration[6/18(33%)TgB27 rats,P=0.01].Macroscopic lesions were located 2 cm above the anastomosis in the TgB27 rats receiving lF82 alone and consisted of ulcerations with a score of 3.5(2-4).Seven out of 18 TgB27 rats(39%)receiving CNCM I-3856 and lF82 had no macroscopic *** to untreated TgB27 animals receiving lF82 alone,coadministration of CNCM I-3856 and lF82 significantly red

关键词： Crohn's disease Recurrence Escherichia coli Probiotic Saccharomyces cerevisiae Colorectal surgery

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气候变化对挠力河径流量影响的定量分析

水科学进展 2010年第6期21卷 765-770页

作者：姚允龙吕宪国王蕾于洪贤 Yun-long l(u) Xian-guo Hong-xian 东北林业大学野生动物资源学院黑龙江哈尔滨150040 中国科学院东北地理与农业生态研究所中国科学院湿地生态与环境重点实验室吉林长春130012 u 黑龙江科技学院建筑工程学院黑龙江哈尔滨150027

三江平原位于黑龙江省东北部,是中国沼泽湿地集中分布区且面积最大的区域,挠力河作为该区域的一条典型沼泽性河流,其径流演变过程受到气候变化和人类活动的双重影响.文中利用水量平衡法和降水-径流经验模型,定量分析了变化期气候变化对... 详细信息

三江平原位于黑龙江省东北部,是中国沼泽湿地集中分布区且面积最大的区域,挠力河作为该区域的一条典型沼泽性河流,其径流演变过程受到气候变化和人类活动的双重影响.文中利用水量平衡法和降水-径流经验模型,定量分析了变化期气候变化对径流的影响,并比较了两种方法的优劣性.研究结果表明:50年来挠力河变化期(1968～2005年)内的年径流量的变化大约40%是由气候变化引起.气候变化对径流量影响的主导因素是降水量的变化,降水量变化对宝清站和菜嘴子站径流量减少的贡献率分别为43%和35%.蒸发量变化对两水文站径流量减少的贡献率为10%左右.利用水量平衡法研究气候变化对河流径流量的影响,其研究结果要优于一般的降水-径流经验模型法,但经验模型也不失为一种快速且简便的方法.

关键词：气候变化挠力河河流径流量定量分析 climate change 经验模型水量平衡法降水量变化贡献率沼泽性河流主导因素沼泽湿地演变过程双重影响人类活动区域年径流量结果黑龙江省方法

Zircon and Monazite Ages Constraints on Devonian Magmatism and Granulite-Facies Metamorphism in the Southern Qaidam Block:Implications for Evolution of Proto-and Paleo-Tethys in East Asia

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Journal of Earth Science 2018年第5期29卷 1132-1150页

作者： Jin ba lu Zhang Chuan He Neng-Song Chen Timothy M.Kusky Qinyan Wang Yusheng Wan Xiaoming liu School of Earth Sciences China University of GeosciencesWuhan 430074China College of Earth Science Chengdu University of TechnologyChengdu 610059China Sichuan Institute of Geological Survey Chengdu 610081China Center for Global Tectonics China University of GeosciencesWuhan 430074China Beijing SHRIMP Center Beijing 100037China State Key laboratory of Continental Dynamics Department of GeologyNorthwest UniversityXi'an 710069China

High-temperature magma generation process and granulite-facies metamorphism can provide important information about mantle-crustal interaction and tectonic evolution. The strongly peralu- minous monzonite pluton, the Jinshuikou cordierite granite on the southern margin of the Qaidam Block, can provide important information about the mantle-crustal interaction and constraints on tectonic tran- sition from Proto-Tethys to Paleo-Tethys. This pluton develops enclaves of mafic granulite, amphibolite and quartzofeldspathic rocks, and is cut by massive monzonitic leuco-granite veins. Zircon and monazite u-Pb dating for the cordierite granite, the granulite enclaves and a massive monzonitic leuco-granite vein reveal that the cordierite granitic magma was generated from Mesoproterozoic continental crust with protolith derived from a provenanee that was composed of 〉2.8 ga old recycled crustal materials and re- corded a -1.7 ga magmatic event. The continental crust underwent low-pressure granulite-facies metamorphism at -380 Ma ago, whereas the cordierite granite magmas was generated and emplaced during 380 Ma, followed by intrusion of the massive monzonitic leuco-granite vein at circa 370-330 Ma. These data suggest that after the final closure of Proto-Tethys Ocean spreading along the southern Qaidam Block at -420 Ma, break-off of the subducted slab or delamination of the lower crustal base and upwelling of the asthenospheric mantle beneath the southern Qaidam Block occurred before the Mid-Devonian, and that the initiation of the Paleo-Tethys tectonics might initiate near the end of Early-Carboniferous in the East Kunlun-Qaidam region, East Asia.

关键词： zircon and monazite u-Pb geochronology cordierite peraluminous granite low pressure granulite Proto- and Paleo-Tethys evolution East Kunlun-Qaidam.

基于DSM返工风险评价矩阵的项目优化与仿真

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系统工程理论与实践 2010年第9期30卷 1665-1671页

作者：杨青吕杰峰北京科技大学经济管理学院北京100083

针对项目中活动返工的不确定性,由返工概率矩阵和返工影响强度矩阵共同构成了DSM返工风险评价矩阵,提出了基于返工风险的遗传算法(Rework risk ga,RRga),同时考虑返工风险、反馈个数、反馈距离及活动的时间和费用建立了DSM优化目标函数... 详细信息

针对项目中活动返工的不确定性,由返工概率矩阵和返工影响强度矩阵共同构成了DSM返工风险评价矩阵,提出了基于返工风险的遗传算法(Rework risk ga,RRga),同时考虑返工风险、反馈个数、反馈距离及活动的时间和费用建立了DSM优化目标函数,改进了传统遗传算法的变异算子和变异概率.通过对典型案例进行优化及其结果的仿真,验证了RRga算法可明显降低返工导致的项目费用和时间,并降低其结果的波动性.

关键词：项目管理设计结构矩阵(DSM) 返工风险评价矩阵遗传算法优化

Salt effect on molecular orientation at air/liquid methanol interface

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Chinese Chemical letters 2016年第4期27卷 535-539页

作者： Xia li gang-Hua Deng Rong-Juan Feng Ke lin Zhen Zhang Yu ba Zhou lu Yuan Guo Beijing National laboratory for Molecular Sciences State Key Laboratory of Molecular Reaction Dynamics Institute of Chemistry Chinese Academy of Sciences Hefei National laboratory for Physical Sciences at the Microscale University of Science and Technology of China School of Physics and Optoelectronic Engineering Xidian University

The salt effects on molecular orientation at air/liquid methanol interface were investigated by the polarization-dependent sum frequency generation vibrational spectroscopy（SFG-VS）. We clarified that the average tilting angle of the methyl group to be u = 308 58 at the air/pure methanol surface assuming a d-function orientational distribution. upon the addition of 3 mol/l Na I, the methyl group tilts further away from the surface normal with a new u = 418 38. This orientational change does not explain the enhancement of the SFG-VS intensities when adding Na I, implying the number density of the methanol molecules with a net polar ordering in the surface region also changed with the Na I concentrations. These spectroscopic findings shed new light on the salt effects on the surfaces structures of the polar organic solutions. It was also shown that the accurate determination of the bulk refractive indices and Raman depolarization ratios for different salt concentrations is crucial to quantitatively interpret the SFG-VS data.

关键词： Surface orientation Air/liquid interface Salt effect Sum frequency generation Methanol

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铜、镉污染对小麦种子萌发及幼苗生长的影响

种子 2012年第9期31卷 108-111页

作者：吕笃康巴音山赵玉伊犁师范学院化学与生物科学学院新疆伊宁835000 新疆生产建设兵团第二中学新疆乌鲁木齐830002

以小麦种子为试材,通过水培试验研究了铜、镉污染对小麦种子萌发及幼苗生长的影响。结果表明,在实验所选的胁迫浓度范围内,单一铜污染时,对小麦种子萌发初期有短暂的促进作用,小麦种子发芽率随着Cu2+浓度的升高,呈先升后降。在20 mg/l C... 详细信息

以小麦种子为试材,通过水培试验研究了铜、镉污染对小麦种子萌发及幼苗生长的影响。结果表明,在实验所选的胁迫浓度范围内,单一铜污染时,对小麦种子萌发初期有短暂的促进作用,小麦种子发芽率随着Cu2+浓度的升高,呈先升后降。在20 mg/l Cu2+处理时出现了毒性兴奋效应现象。铜、镉污染对小麦幼苗的苗长和根长的抑制作用较为显著。根据综合效应指标,铜、镉复合污染对小麦种子萌发的影响表现形式为铜、镉的协同作用。

关键词：铜镉小麦种子萌发幼苗生长

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新版GB/T 7704关键问题解析

理化检验（物理分册） 2017年第7期53卷 457-465页

作者：吕克茂巴发海吕东艳邯郸市爱斯特应力技术有限公司邯郸056107 上海材料研究所上海200437 北京科技大学北京100084

分析了我国X射线应力测试技术的发展现状,在深入理解欧盟标准EN 15305-2008的基础上,对新版GB/T 7704中若干关键问题进行了解析,阐述了其必要性、合理性和可行性,以帮助广大X射线应力测试工作者正确理解和执行标准,为获得比较可靠的试... 详细信息

分析了我国X射线应力测试技术的发展现状,在深入理解欧盟标准EN 15305-2008的基础上,对新版GB/T 7704中若干关键问题进行了解析,阐述了其必要性、合理性和可行性,以帮助广大X射线应力测试工作者正确理解和执行标准,为获得比较可靠的试验结果提供必要的理论解惑和技术支持。

关键词： GB/T 7704 残余应力 X射线衍射残余应力测定