检索结果-南通市图书馆

Science China Chemistry 2020年第11期63卷 1652-1658页

作者： Ziyu Gan Guoqing Li Xiaobo Yang Qiuli Yan Guiyun Xu Gaoyang Li Yuan-ye jiang Daoshan Yang Key Laboratory of Optic-electric Sensing and Analytical Chemistry for Life Science Ministry of EducationShandong KeyLaboratory of Biochemical AnalysisCollege of Chemistry and Molecular EngineeringQingdao University of Science and TechnologyQingdao 266042China School of Chemistry and Chemical Engineering Qufu Normal UniversityQufu 273165China Institute of Catalysis for Energy and Environment College of Chemistry&Chemical EngineeringShenyang Normal UniversityShenyang 110034China Qingdao West Coast New Area Poli Junior Middle School Qingdao 266409China

An efficient and eco-friendly protocol for the construction of naphtho[2,1-d]thiazol-2-amines through visible-light photoredox-catalyzed C(sp2)–H/S–H cross-dehydrogenative coupling reactions between 2-isothiocyanatonaphthalenes and amines was *** this reaction,the new C–N and C–S bonds are formed simultaneously in a single *** new method provides a straightforward approach for constructing valuable sulfur-containing compounds.

关键词： visible light cross-dehydrogenative coupling C-S bond synthetic methods metal-free

A New Type of Submerged-Arc Flux-Cored Wire Used for Hardfacing Continuous Casting Rolls

在线全文

学校读者我要写书评

暂无评论

Journal of Iron and Steel Research International 2011年第11期18卷 74-79页

作者： YANG Ke ZHANG Zhi-xi HU Wang-qin BAO ye-feng jiang Yong-feng College of Mechanical and Electrical Engineering Hohai University Changzhou 213022 Jiangsu China

It is expected that the welding hardfacing of continuous casting rolls has better welding performance and higher wear resistance. A new type of submerged-arc hardfacing flux-cored wire has been developed through nitrogen replacing part of carbon and addition of the nitrogen-fixing elements of niobium and titanium. And microstructure, degree of hardness and high-temperature wear resistance of its deposited metal samples were also investigated. It is found that the microstructure is martensite, residual austenite and carbonitride precipitates. As a result, the hardfacing metal with homogeneous distribution of very fine carbonitride particles had high hardness and excellent wear-re- sisting property during high-temperature wear, which could significantly extend the service life of continuous casting rolls.

关键词： submerged-arc flux-cored wire hardfacing high-temperature wear resistance continuous casting roll

Effect of Stem Density on Leaf Nutrient Dynamics and Nutrient Use Efficiency of Dwarf Bamboo

在线全文

学校读者我要写书评

暂无评论

Pedosphere 2009年第4期19卷 496-504页

作者： WU Fu-Zhong YANG Wan-Qin WANG Kai-Yun WU Ning LU ye-jiang Chengdu Institute of Biology Chinese Academy of Sciences Chengdu 610041 (China) Faculty of Forestry Sichuan Agricultural University Ya'an 625014 (China) Graduate University of the Chinese Academy of Sciences Beijing 100049 (China) Shanghai Key Laboratory of Urbanization Processes and Ecological Restoration East China Normal University Shanghai 200062 (China)

The monthly dynamics of nitrogen （N） and phosphorus （P） concentrations and stocks in leaves, resorption efficiency, and resorption proficiency as well as leaf-level use efficiency, nutrient productivity, and mean residence time were studied to understand the effect of stem density of dwarf bamboo （Fargesia denudata Yi） on leaf-level N and P use efficiency in three dwarf bamboo stands with different stem densities under bamboo-fir （Picea puvpurea Mast.） forest over one growing period in the Wanglang National Nature Reserve, Sichuan, China. Dwarf bamboo density had little effect on the dynamics pattern of both N and P concentrations, stocks, resorption efficiency, and resorption proficiency, but strongly affected their absolute values and leaf-level use efficiency. Higher density stands stored more nutrients but had lower concentrations. There was a clear difference in the resorption of limiting nutrient （N） and non-limiting nutrient （P） among the stands. Phosphorus resorption efficiency, N resorption proficiency, and P resorption proficiency increased with increase of stem density, but no significant variation of N resorption efficiency was found among the stands. Moreover, the higher density stands used both N and P more efficiently with higher N productivity and higher P mean residence time, respectively. Higher P productivity was found in the lower density stands, but there was no clear variation in the N mean residence time among stands. These suggested that the higher density stands may have more efficient strategies for utilizing nutrients, especially those which are limiting .

关键词： mean residence time nutrient productivity nutrient resorption

Insulin-like growth factor-1 induces lymphangiogenesis and facilitates lymphatic metastasis in colorectal cancer

在线全文

学校读者我要写书评

暂无评论

World Journal of Gastroenterology 2013年第43期19卷 7788-7794页

作者： Zhen-Jun Li Xiao-jiang Ying Hong-Liang Chen Ping-jiang ye Zhi-Liang Chen Gang Li Hua-Feng jiang jiang Liu Shu-Zhen Zhou Department of Colorectal Surgery Shaoxing People’s Hospital Shaoxing Hospital of Zhejiang University

AIM:To investigate the expression of insulin-like growth factor-1(IGF-1)/insulin-like growth factor-1 receptor(IGF-1R)in colorectal cancer(CRC)tissues and to analyze their correlation with lymphangiogenesis and lymphatic ***:Immunohistochemistry was used to evaluate IGF-1 and IGF-1R expression and lymphatic vessel density(LVD)in 40 CRC *** correlation between IGF-1/IGF-1R and LVD was *** of IGF-1 on migration and invasion of CRC cells were examined using transwell chamber assays.A LoVo cell xenograft model was established to further detect the role of IGF-1 in CRC lymphangiogenesis in vivo. RESULTS:Elevated IGF-1 and IGF-1R expression in CRC tissues was correlated with lymph node metastasis(r=0.715 and 0.569,respectively,P<0.05)and tumor TNM stage(r=0.731 and 0.609,P<0.05).A higher LVD was also found in CRC tissues and was correlated with lymphatic metastasis(r=0.405,P<0.05).A positive correlation was found between LVD and IGF-1R expression(r=0.437,P<0.05).Transwell assays revealed that IGF-1 increased the migration and invasion of CRC *** vivo mouse studies showed that IGF-1 also increased LVD in LoVo cell ***:IGF-1/IGF-1R signaling induces tumorassociated lymphangiogenesis and contributes to lymphatic metastasis of CRC.

关键词： Colorectal cancer Insulin-like growth factor-1 Insulin-like growth factor-1 receptor Lymphangiogenesis Lymphatic metastasis

EZH2 and STAT6 expression profiles are correlated with colorectal cancer stage and prognosis

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

World Journal of Gastroenterology 2010年第19期16卷 2421-2427页

作者： Wang, Cheng-Gang ye, Ying-jiang Yuan, Jing Liu, Fang-Fang Zhang, Hui Wang, Shan Beijing Univ Dept Surg Gastroenterol Surg Oncol Lab Peoples Hosp Beijing 100044 Peoples R China Chinese Peoples Liberat Army Hosp Dept Pathol Beijing 100036 Peoples R China Beijing Univ Peoples Hosp Dept Pathol Beijing 100044 Peoples R China

AIM: To investigate the role of enhancer of zeste homologue 2 (EZH2) and STAT6 immunohistochemistry in the evaluation of clinical stages and prognosis of colorectal cancer (CRC). METHODS: The expression patterns were examined by immunohistochemistry in both tumor and adjacent non-neoplastic tissues of 119 CRC patients who underwent operation during the time period from 2002 to 2004. RESULTS: The positive rates of EZH2 and STAT6 in CRC cases were 69.7% (83 of 119) and 60.5% (72 of 119), respectively, and there was signifi cant differ-ence when compared with tumor adjacent non-neoplastic tissues (P < 0.05). In all CRC cases, patientswith EZH2-positive, or STAT6-positive expression had lower survival rates than those with EZH2-negative or STAT6-negative expression (P = 0.002 and P = 0.005, respectively). Co-expression of EZH2 and STAT6 showed signifi cantly higher levels in CRC cases of high clinical TNM stages (P = 0.001), and the expression of STAT6 was also correlated with lymph node metastasis and distant metastasis (P = 0.001 and P = 0.016, respectively). Multivariate analysis revealed that EZH2 expression was an independent prognostic indicator of CRC (P = 0.039). CONCLUSION: EZH2 and STAT6 expressions have significant values in distinguishing clinical stages of CRC and predicting the prognosis of the patients.

关键词： Colorectal Neoplasms Enhancer of zeste homologue 2 STAT6 Immunohistochemistry

Ligand-promoted reductive coupling between aryl iodides and cyclic sulfonium salts by nickel catalysis

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11期35卷 349-354页

作者： Junxin Li Chao Chen Yuzhen Dong Jian Lv Jun-Mei Peng Yuan-ye jiang Daoshan Yang Key Laboratory of Optic-electric Sensing and Analytical Chemistry for Life Science MOECollege of Chemistry and Molecular EngineeringQingdao University of Science and TechnologyQingdao 266042China Laboratory of Catalytic Conversion and Clean Energy in Universities of Shandong Province School of Chemistry and Chemical EngineeringQufu Normal UniversityQufu 273165China Department of Medicinal Chemistry School of PharmacyHengyang Medical SchoolUniversity of South ChinaHengyang 421001China

Developing applicable methods to forge linkages between sp^(3)and sp^(2)-hydridized carbons is of great significance in drug *** show here a new,Ni-catalyzed reductive cross-coupling reaction that forms Csp^(3)-Csp^(2)bonds from aryl iodides and cyclic sulfonium ***,Csp^(3)-Csp^(2)bonds can be forged selectively at the iodine-bearing carbon of bromo(iodo)arenes which is usually recognized as a huge challenge under the catalytic reductive cross-coupling(CRCC)*** and computational mechanistic studies support LNi~IAr as an active species,while the untraditional anti-Markovnikov selective alkylation of asymmetric sulfonium salts is determined by the oxidative S-substitution of sulfonium salts with LNi~*** protocol further expands the range of alkyl electrophiles under the CRCC conditions and provides a new strategy for the construction of Csp^(3)-Csp^(2)bonds.

关键词： Reductive cross-coupling reaction Csp^(3)-Csp^(2)bonds Nickel catalysis Sulfonium salts Alkylation

Characterizations on Mechanical Properties and In Vitro Bioactivity of Biomedical Ti–Nb–Zr–CPP Composites Fabricated by Spark Plasma Sintering

在线全文

学校读者我要写书评

暂无评论

Acta Metallurgica Sinica(English Letters) 2016年第11期29卷 1073-1080页

作者： Zheng-Yuan He Lei Zhang Wen-Rui Shan Yu-Qin Zhang ye-Hua jiang Rong Zhou Jun Tan School of Materials Science and Engineering Kunming University of Science and Technology Kunming 650093China National-local Joint Engineering Laboratory of Metal Advanced Solidification Forming and Equipment Technology Kunming 650093 China Engineering Technology Research Center of Titanium Products and Application of Yunnan Province Kunming 650093 China IFW Dresden Institute for Complex MaterialsP.O. Box 27 01 16 01171 Dresden Germany

To alleviate the bio-inert of Ti alloys as hard tissue implants, Ti–35Nb–7Zr–xCPP（calcium pyrophosphate,x = 5, 10, 15, 20 wt%） composites were prepared by mechanical alloying（MA） and following spark plasma sintering（SPS）. Mechanical behaviours and in vitro bioactivity of these composites were investigated systematically. Results showed that the composites consisted of β-Ti matrix, α-Ti, and metal–ceramic phases such as CaO, CaTiO3, CaZrO3, and TixPy. With increasing CPP content, the composites had higher strength（over 1500 MPa） and higher elastic modulus, but suffered almost zero plastic deformation together with lower relative density. When the CPP contents were 5 and 10 wt%,the compressive elastic moduli were 44 and 48 GPa, respectively, which were close to those of natural bones. However, the compressive elastic modulus of the composites increased significantly when CPP contents exceed 10 wt%, thus deteriorating the mechanical compatibility of the composites owing to more α-Ti and metal–ceramic phases. Besides, the surface of Ti–35Nb–7Zr–10CPP composite was deposited as a homogeneous apatite layer during soaking in simulated body fluid（SBF）. It indicates a good bioactivity between the implant materials and living bones.

关键词： Composites Spark plasma sintering Microstructure Mechanical behaviours Bioactivity

First Principles Study on the Stability and Mechanical Properties of MB (M=V, Nb and Ta) Compounds

在线全文

学校读者我要写书评

暂无评论

Chinese Physics Letters 2013年第11期30卷 144-148页

作者： QI Chen-Jin FENG Jing ZHOU Rong-Feng jiang ye-Hua ZHOU Rong Faculty of Materials Science and Engineering Kunming University of Science and TechnologyKunming 650093 School of Engineering and Applied Science Harvard UniversityCambridgeMA 02138USA

The first principles calculations based on density functional theory are performed to investigate the stability,chemical bonding,elastic constants,hardness and Debye temperature of MB(M=V,Nb and Ta)*** structures of these borides are optimized,and the lattice parameters are in good agreement with the experimental *** calculated cohesive energy and formation enthalpy indicate that they are of a thermodynamically stable *** mechanical properties,including elastic constants Cij,bulk modulus,Young's modulus,shear modulus and Poisson's ratio,are *** bulk moduli of them ranging from 263.0 to 278.4 GPa are larger than many common Laves phases and TaB with 278.4 GPa being the largest bulk modulus value among *** population analysis is used to analyze the chemical bonds in these *** hardness of the compounds is also evaluated,and the result reveals that TaB is the hardest compound among *** Debye temperature of MB is *** results show that the values of MB compounds range from 419.3 to 794.3 K.

关键词： compounds structure modulus

Rapid formation of Csp^(3)–Csp^(3) bonds through copper-catalyzed decarboxylative Csp^(3)–H functionalization

在线全文

学校读者我要写书评

暂无评论

Chinese Chemical Letters 2023年第1期34卷 326-332页

作者： Wenwen Cui Yu Li Xufeng Li Junxin Li Xiuyan Song Jian Lv Yuan-ye jiang Daoshan Yang Key Laboratory of Optic-Electric Sensing and Analytical Chemistry for Life Science MOECollege of Chemistry and Molecular EngineeringQingdao University of Science and TechnologyQingdao 266042China School of Chemistry and Chemical Engineering Qufu Normal UniversityQufu 273165China Zhejiang Wansheng Co. Ltd.Linhai 317000China Key Laboratory of Bioorganic Phosphorus Chemistry and Chemical Biology(Ministry of Education) Department of ChemistryTsinghua UniversityBeijing 100084China

Transition-metal-catalyzed decarboxylative and C–H functionalization strategy for the construction of Csp^(2)-Csp^(2),Csp^(2)-Csp,and Csp^(2)-Csp^(3) bonds has been extensively ***,research surveys of this synthetic strategy for the Csp^(3)-Csp^(3) bond forming reactions are surprisingly ***,we present an efficient approach for the rapid formation of Csp^(3)–Csp^(3) bond through copper-catalyzed decarboxylative Csp^(3)–H *** present method should provide a useful access to C3-substituted indole scaffolds with possible biological *** experiments and DFT calculations supported a dual-Cu(Ⅱ)-catalytic cycle involving rate-determining decarboxylation in an outer-sphere radical pathway and spin-crossover-promoted C–C bond *** strategy offers a promising synthesis method for the construction of Csp^(3)–Csp^(3) bond in the field of synthetic and pharmaceutical chemistry and extends the number of still limited copper-catalyzed decarboxylative Csp^(3)–Csp^(3) bond forming reaction.

关键词： Copper Cross-coupling Csp^(3)-H functionaliztion Decarboxylation Csp^(3)–Csp^(3)bond formation

On China's Role in Arctic Governance——With the Case Study of China's Reaction during US Arctic Council Chairmanship from 2015 to 2017

在线全文

学校读者我要写书评

暂无评论

学术界 2016年第1期 257-262页

作者： ye jiang Institute for Global Governance Studies Shanghai Institute for International Studies

This article mainly focuses on China’s role in Arctic governance through analysis of China’s stance in Arctic affairs with the explanation why China holds such *** on this it has a case study of China’s reaction during United States Arctic Council chairmanship from 2015 to 2017 to further exam the China’s role. According to the argument of the article there are three parts in China’s stance in Arctic governance that is part of global governance China has already participated in,which include recognizing and respecting the rights of the countries in the region,contending China to have the responsibility to provide public goods in Arctic governance,and considering the scientific research in the Arctic being a priority of China’s participation in Arctic governance. With such stance it is quite easy to understand that addressing climate change is the main area that China will co- operate with United States in Arctic governance in United States Arctic Council Chairmanship from 2015 to2017. Besides the climate change area China will also cooperate with United States in improving economic and living conditions in Arctic communities and in Arctic Ocean safety,security and stewardship fairly actively because all of these are part of Arctic governance.

关键词： Arctic governance global governance Arctic Council United States China