检索结果-南通市图书馆

Boundary Reducible Handle Additions on Simple 3-Manifolds

在线全文

学校读者我要写书评

暂无评论

Acta Mathematica Sinica,English Series 2009年第2期25卷 235-244页

作者： Yan Nan li Rui feng qiu Ming Xing ZHANG Department of Applied Mathematics Dalian University of Technology Dalian 116023 P. R. China

Let M be a simple manifold, and F be a component of δM of genus two. For a slope γ on F, we denote by M（γ） the manifold obtained by attaching a 2-handle to M along a regular neighborhood of γon F. In this paper,... 详细信息

关键词： δ-reducible Scharlemann cycle simple manifold

体外产气法研究丁酸梭菌对瘤胃发酵特性的影响

在线全文

学校读者我要写书评

暂无评论

饲料研究 2024年第9期47卷 7-11页

作者：卢俊言王明亚吴春会李素霞徐宏建曹玉凤李秋凤河北农业大学动物科技学院河北保定071000 承德市畜牧工作站河北承德067000

试验旨在采用体外产气法研究全混合饲粮(TMR)中补充不同水平的丁酸梭菌对产气量、发酵参数与养分消化率的影响,确定丁酸梭菌在肉牛饲粮中的适宜添加量。试验选用选择装有永久性瘘管的荷斯坦阉牛作为瘤胃液供体,以TMR为培养底物。对照组(... 详细信息

试验旨在采用体外产气法研究全混合饲粮(TMR)中补充不同水平的丁酸梭菌对产气量、发酵参数与养分消化率的影响,确定丁酸梭菌在肉牛饲粮中的适宜添加量。试验选用选择装有永久性瘘管的荷斯坦阉牛作为瘤胃液供体,以TMR为培养底物。对照组(CON组)只含有培养底物,丁酸梭菌试验组在培养底物的基础上添加浓度为2×10^(8)(CB1组)、4×10^(8)(CB2组)、6×10^(8)(CB3组)、8×10^(8)(CB4组)、10×10^(8)CFU/kg(CB5组)的丁酸梭菌,每个水平设6个重复。结果显示:发酵时间为2 h和4 h时,CB1组体外产气量显著低于其他组(P0.05)。CB3组、CB4组和CB5组的乙酸、丙酸、总酸含量显著高于CON组(P<0.05)。CB1组、CB2组和CB3组异丁酸含量显著高于CON组(P<0.05)。各试验组干物质消化率(DMD)、中性洗涤纤维降解率(NDFD)均显著高于CON组(P<0.05)。CB2组酸性洗涤纤维降解率(ADFD)显著高于CON组(P<0.05)。研究表明,添加丁酸梭菌可以提高产气量、NH3-N、乙酸、丙酸、总挥发酸含量以及DMD,丁酸梭菌的适宜添加量为6×10^(8)CFU/kg。

关键词：荷斯坦阉牛丁酸梭菌产气量消化率

The reversible addition-fragmentation chain transfer(RAFT) miniemulsion polymerization of vinyl acetate mediated by xanthate

同方期刊数据库博看期刊评论

在线全文

学校读者我要写书评

暂无评论

Chinese Chemical Letters 2009年第6期20卷 733-737页

作者： Bo Jiang Qing Hua Zhang Xiao li Zhan feng qiu Chen Department of Chemical and Biochemical Engineering Zhejiang University Hangzhou 310027 People's Republic of China

The reversible addition-fragmentation chain transfer （RAFT） miniemulsion polymerization of vinyl acetate （VAc） mediated by methyl （methoxycarbonothioyl） sulfanyl acetate （MMSA） was carried out. The results showed that polymerizations initiated by AIBN and KPS proceeded in a controlled way. The RAFT miniemulsion polymerization of VAc initiated by KPS showed the shorter inhibition period, higher propagation rate coefficient and final conversion than those in experiment initiated by AIBN. When the monomer conversion reached 25%, the polydispersity index （PDI） of polymer became broad, which was related to chain transfer reaction in RAFT miniemulsion of VAc.

关键词： Xinyl acetate Xanthate Reversible addition-fragmentation chain transfer Miniemulsion

Monomer reactivity ratios for fluoroacrylate and butyl methacrylate in miniemulsion copolymerizations initiated by potassium persulphate

在线全文

学校读者我要写书评

暂无评论

Chinese Chemical Letters 2009年第4期20卷 478-482页

作者： Qing Hua Zhang Zhen Huan Luo Xiao li Zhan feng qiu Chen College of Materials Science and Chemical Engineering Zhejiang University Hangzhou 310027 China

Miniemulsion copolymerization of butyl mathacrylate （BMA） with fluoroacrylate （HFMA, TFMA） was carried out at 70 ℃ by employing potassium persulphate （KPS） as initiator. Copolymer compositions at low conversion levels were determined by ^1H NMR spectra techniques. The reactivity ratios were evaluated by employing Kellen-Tudos （K-T） methods, which yields the apparent reactivity ratios, rBMA = 0.74, rHFMA = 0.87 and rBMA = 0.73, rTFMA = 0.75, respectively, and Q- and e-values of HFMA and TFMA were calculated by the Alfrey-Price method. The results show that HFMA and TFMA are more active than BMA, and the cross-propagation rate constant is greater than the self-propagation one in these two copolymerizations.

关键词： Fluoroacrylate Reactivity ratios Miniemulsion Copolymerization

Small intestinal hemolymphangioma with bleeding:A case report

在线全文

学校读者我要写书评

暂无评论

World Journal of Gastroenterology 2012年第17期18卷 2145-2146页

作者： Yan-Fei Fang li-feng qiu Ying Du Zhi-Nong Jiang Min Gao Department of Gastroenterology Sir Run Run Shaw Hospital College of Medicine Zhejiang University Hangzhou 310016 Zhejiang Province China Department of Emergency The First MunicipalHospital of Hangzhou Hangzhou 310006 Zhejiang ProvinceChina Department of Pathology Sir Run Run ShawHospital College of Medicine Zhejiang University Hangzhou310016 Zhejiang Province China

Small intestinal hemolymphangioma is a very rare benign *** was only one report of a hemolymphangioma of the pancreas invading to the duodenum until March *** we describe the first case of small intestinal hemolymphangioma with bleeding in a 57-year-old *** presented with persistent gastrointestinal bleeding and endoscopy revealed a small intestinal *** resection of the small intestine was thus performed and the final pathological diagnosis was *** also highlight the difficultly in making an accurate preoperative diagnosis in spite of modern imaging *** arrive at a definitive diagnosis and exclude malignancy,partial resection of the small intestine was considered to be the required treatment.

关键词： Hemolymphangioma Small intestine Gastrointestinal bleeding Benign tumor

Self assembled electron blocking and lithiophilic interface towards dendrite-free solid-state lithium battery

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chinese Chemical Letters 2024年第4期35卷 220-225页

作者： Caixia li Yi qiu Yufeng Zhao Wuliang feng Institute for Sustainable Energy&College of Sciences Shanghai UniversityShanghai 200444China Key Laboratory of Advanced Energy Materials Chemistry(Ministry of Education) Nankai UniversityTianjin 300071China

The poor interfacial contact is one of the biggest challenges that solid-state lithium batteries suffer *** the solid-state electrolyte surface energy by transforming the interface from lithiophobic to lithiophilic is effective to promote the interfacial contact, but electronic conductive interphases usually increase the risk of electron attack, thus leading to uncontrollable li dendrite growth. Herein, we propose a self-assembled thermodynamic stable li I interphase to simultaneously improve the interfacial contact between the garnet electrolyte li_7La_(3)Zr_(2)O_(12)(LLZO) and li anode, and prohibit the electron attack. The direct contact between LLZO and li and the high temperature li melting process was ascribed to Zr4+reduction, which facilitated li dendrite formation and propagation. With the modification of the high lithiophilic I_(2) thin film, the area specific interfacial resistance of LLZO/li was reduced from 1525 Ω/cm^(2) to 57 Ω/cm^(2). More importantly, LLZO was protected from being reduced due to the outstanding electronic insulativity of the li I interphase, which leaded to a high critical current density of 1.2/7.0 m A/cm^(2) in the time/capacity-constant modes, respectively.

关键词： li_7La_(3)Zr_(2)O_(12) liI interphase Interfacial contact li dendrite Thermodynamic stable

植物精油对西门塔尔公牛血清抗氧化性能和直肠微生物的影响

在线全文

学校读者我要写书评

暂无评论

饲料研究 2024年第11期47卷 1-6页

作者：王晓林吴春会肖阳李伟刘春海张秀江王明亚李秋凤河北农业大学动物科技学院河北保定071000 定兴县动物疫病预防控制中心河北保定071000 黑龙江省农业科学院畜牧兽医分院黑龙江齐齐哈尔161005 辽宁菲迪饲料科技有限责任公司辽宁兴城125100 保定市农业局河北保定071000

试验旨在研究植物精油(PEO)对西门塔尔公牛血清抗氧化性能和直肠微生物的影响。选择56头体重(564.39±7.09)kg、体况良好的西门塔尔公牛,随机分成4组,每组14个重复,每个重复1头牛。对照组(CK)饲喂基础饲粮,处理组在基础饲粮中分别添加0.... 详细信息

试验旨在研究植物精油(PEO)对西门塔尔公牛血清抗氧化性能和直肠微生物的影响。选择56头体重(564.39±7.09)kg、体况良好的西门塔尔公牛,随机分成4组,每组14个重复,每个重复1头牛。对照组(CK)饲喂基础饲粮,处理组在基础饲粮中分别添加0.5(PEO1)、1.0(PEO2)、1.5(PEO3)g/(头·d)的PEO。预试期7 d,正式试验期60 d。结果表明:试验第30 d,PEO2组血清总抗氧化能力(T-AOC)显著高于CK组(P0.05)。在直肠微生物门水平上,PEO对各菌门的相对丰度无显著影响(P>0.05)。在直肠微生物科水平上,PEO1组韦荣氏菌科(Veillonellaceae)相对丰度显著低于CK组(P<0.05)。PEO2组克里斯滕森菌科(Christensenellaceae)相对丰度显著高于CK组、PEO1组和PEO3组(P<0.05)。在直肠微生物属水平上,PEO3组普雷沃氏菌属(Prevotella)相对丰度显著高于CK组和PEO2组(P<0.05)。PEO2组丁酸弧菌(Butyrivibrio)相对丰度显著高于CK组、PEO1组和PEO3组(P<0.05)。研究表明,饲粮中添加PEO可以提高西门塔尔公牛血清抗氧化性能,改善肠道微生物菌群结构,以1.0 g/(头·d)为适宜添加量。

关键词：植物精油西门塔尔公牛抗氧化性能直肠微生物

维普期刊数据库博看期刊

不同来源纤维素降解菌的筛选、鉴定及产酶能力的比较

在线全文

学校读者我要写书评

暂无评论

草地学报 2024年第4期32卷 1252-1258页

作者：陈欢史子浩吴春会李秋凤于晓梦徐领贾海阔刘震灵王明亚河北农业大学动物科技学院河北保定071000 农业农村部奶牛健康养殖重点实验室(部省共建) 河北保定071000

为了选育纤维素高效降解菌,提高纤维素降解效率。本研究从肉牛瘤胃液、肉牛粪便,蝗虫肠道末筛选纤维素降解能力较强的株系,对其进行生物学鉴定和酶活性比较。结果表明,从肉牛瘤胃液中筛选出纤维素降解株系L7,L8-1和L9,分别鉴定为高地芽... 详细信息

为了选育纤维素高效降解菌,提高纤维素降解效率。本研究从肉牛瘤胃液、肉牛粪便,蝗虫肠道末筛选纤维素降解能力较强的株系,对其进行生物学鉴定和酶活性比较。结果表明,从肉牛瘤胃液中筛选出纤维素降解株系L7,L8-1和L9,分别鉴定为高地芽孢杆菌(Bacillus altitudinis)、暹罗芽孢杆菌(***)和枯草芽孢杆菌(***);从蝗虫肠道末中筛选得到株系H2-1和H3-1,分别鉴定为枯草芽孢杆菌(***)和解蛋白芽孢杆菌(***);从肉牛粪便中筛选得到株系F8-2被鉴定为高地芽孢杆菌(***)。其中降解能力最强的株系为L7,其全酶(FPA)、外切葡聚糖酶(C_(1)),内切葡聚糖酶(CMC)和β-葡萄糖苷酶(β-Gase)活性分别为4.28,1.89,5.57,2.30 U·mL^(-1)。菌落D/d平均值与FPA,CMC,C_(1),β-Gase的酶活性呈显著正相关(P<0.05)。本研究筛选得到株系L7具有较强的纤维素降解能力,为提高饲料转化率提供了更多可能。

关键词：纤维素降解菌酶活性芽孢杆菌

维普期刊数据库博看期刊

An approximate analytical model for unconventional reservoir considering variable matrix blocks and simultaneous matrix depletion

在线全文

学校读者我要写书评

暂无评论

Petroleum Science 2024年第1期21卷 352-365页

作者： Kai-Xuan qiu Jia li Dong feng Shi-Ming Wei Gang Lei Jiangmen Laboratory of Carbon Science and Technology Jiangmen529100GuangdongChina The Hong Kong University of Science and Technology(Guangzhou) Guangzhou511400GuangdongChina China University of Geosciences(Beijing) Beijing100083China China University of Petroleum(Beijing) Beijing102249China China University of Geosciences(Wuhan) Wuhan430074HubeiChina Shenzhen Research Institute China University of GeosciencesShenzhen518063GuangdongChina

In regard to unconventional oil reservoirs,the transient dual-porosity and triple-porosity models have been adopted to describe the fluid flow in the complex fracture *** has been proven to cause inaccurate production evaluations because of the absence of matrix-macrofracture *** addition,most of the existing models are solved analytically based on Laplace transform and numerical ***,an approximate analytical solution is derived directly in real-time space considering variable matrix blocks and simultaneous matrix *** simplify the derivation,the simultaneous matrix depletion is divided into two parts:one part feeding the macrofractures and the other part feeding the ***,a series of partial differential equations(PDEs)describing the transient flow and boundary conditions are constructed and solved analytically by ***,a relationship between oil rate and production time in real-time space is *** new model is verified against classical analytical *** the microfracture system and matrix-macrofracture communication is neglected,the result of the new model agrees with those obtained with the dual-porosity and triple-porosity model,***,the new model also has an excellent agreement with the numerical *** model is then applied to two actual tight oil wells completed in western Canada sedimentary *** identifying the flow regime,the solution suitably matches the field production data,and the model parameters are *** these output parameters,we can accurately forecast the production and even estimate the petrophysical properties.

关键词： Analytical solution Unconventional reservoir Variable matrix Simultaneous flow