检索结果-南通市图书馆

Chemoselective electrochemical seleno-cyclization of dienes to medium-sized benzo[b]azocines

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2期35卷 431-435页

作者： Zhichuan Wang Xin Wang Quanxin Li shaofei Ni Dongyang Zhao shubin Yang ge Qiu Kai sun College of Chemistry and Chemical engineering Yantai UniversityYantai 264005China Department of Chemistry and Key Laboratory for Preparation and Application of Ordered structural Materials of Guangdong Province Shantou UniversityShantou 515063China Aix Marseille Univ. CNRSCentrale MarseilleiSm2MarseilleFrance

The preparation of medium-sized benzo[b]azocines has always been challenging because of inherently unfavorable enthalpy and entropy *** report presents a novel approach for accessing 8-membered seleno-benzo[b]azocines via electrochemically-driven *** method enables room-temperature preparation of various structurally diverse medium-sized seleno-benzo[b]*** facile deselenation of the seleno-cyclization products to generate functionalized dienes is an additional benefit of this indispensable *** insights are presented based on radical inhibition experiments and cyclic voltammetry measurements,which elucidate the radical ***,density functional theory calculations further rationalize the rate-determining step and the unique chemoselectivity observed in this transformation.

关键词： Medium-sized n-heterocycles electrocatalysis Radical Mechanistic insights selenylation

Lightweight,strong and High Heat-Resistant Poly(lactide acid)Foams via Microcellular Injection Molding with self-Assembly Nucleating Agent

在线全文

学校读者我要写书评

暂无评论

Chinese journal of Polymer science 2024年第6期42卷 739-750页

作者： Xiao-Hu Bing Wen-Yu Ma Ming-Hui Wu Peng Gao Xiao Zhou Hai-Bin Luo Long Wang Wen-ge Zheng school of materials science and engineering Shanghai UniversityShanghai200444China Ningbo Key Lab of Polymer Materials Ningbo Institute of Material Technology and EngineeringChinese Academy of SciencesNingbo315201China University of Chinese Academy of sciences Beijing100049China

Poly(lactide acid)(PLA)foams have shown considerable promise as eco-friendly alternatives to nondegradable plastic foams,such as polystyrene(Ps)***,PLA foam typically suffers from low heat-resistance and poor cellular structure stemming from its inherent slow crystallization rate and low melt *** this study,a high-performance PLA foam with well-defined cell morphology,exceptional strength and enhanced heat-resistance was successfully fabricated via a core-back microcellular injection molding(MIM)*** scanning calorimetry(DsC)results revealed that the added hydrazine-based nucleating agent(HNA)significantly increased the crystallization temperature and accelerated the crystallization process of ***,the addition of a 1.5 wt%of HNA led to a significant reduction in PLA’s cell size,from 43.5µm to 2.87µm,and a remarkable increase in cell density,from 1.08×10^(7)cells/cm^(3)to 2.15×10^(10)cells/cm^(3).This enhancement resulted in a final crystallinity of approximately 55.7%for the PLA blend foam,a marked improvement compared to the pure PLA ***,at 1.5 wt%HNA concentration,the tensile strength and tensile toughness of PLA blend foams demonstrated remarkable improvements of 136%and 463%,***,the Vicat softening temperature of PLA blend foam increased significantly to 134.8°C,whereas the pure PLA foam exhibited only about 59.7℃.These findings underscore the potential for the preparation of lightweight injection-molded PLA foam with enhanced toughness and heat-resistance,which offers a viable approach for the production of high-performance PLA foams suitable for large-scale applications.

关键词： Poly(lactide acid) Nucleating agent Microcellular injection molding Heat-resistance Toughness

Highly Aromatic Norditerpenoid Heterodimers and Monomers from Trigonostemon fragilis

在线全文

学校读者我要写书评

暂无评论

engineering 2024年第7期38卷 144-154页

作者： jun-su Zhou Long Cheng Yuan Gao Zhan-Peng ge Bin Zhou jing-Ya Li jin-Xin Zhao jian-Min Yue state Key Laboratory of Drug Research Shanghai Institute of Materia MedicaChinese Academy of SciencesShanghai 201203China shandong Laboratory of Yantai Drug Discovery Bohai Rim Advanced Research Institute for Drug DiscoveryYantai 264117China

Four new norditerpenoid heterodimers with different dimerization patterns-namely,trigofragiloids A-C(denoted as compounds 1-3)and(+)-and(-)-trigofragiloid D(compound 4)-and three new phenanthrenone norditerpenoids-namely,trigofragiloids e-G(compounds 5-7)-were isolated from Trigonostemon *** 1 and 2 feature a novel heterodimeric carbon skeleton formed by the conjugation of a tetra-norditerpenoid and an ennea-norditerpenoid;they have been identified as class 2 atropisomers by means of quantum chemical *** 3 is an unprecedented phenylpropanoid-norditerpenoid adduct with a new dimerization ***(+)-and(-)-4 are the first example of s-shaped 1,4-dioxane-fused norditerpenoid *** by the structure elucidation of compound 4,two co-occurring analogues,actephilol A and epiactephilol A,were structurally revised as a pair of geometrical isomers and were identified as two pairs of enantiomers,(+)-and(-)-8 and(+)-and(-)-9,*** structures were characterized using a combined ***,compound 7 exhibits remarkable adenosine triphosphate-citrate lyase(ACLY)inhibition with a halfmaximal inhibition concentration(IC50)value of(0.46±0.11)lmol·L^(-1),as active as the positive control BMs-303141,and a molecular docking study offers deep insight into the interaction between compound 7 and ACLY.

关键词： Norditerpenoid heterodimer Trigonostemon fragilis euphorbiaceae Trigofragiloid structural revision Adenosine triphosphate-citrate lyase(ACLY) inhibitory activity

Metal-Free electrochemical Trifluoromethylation of Imidazole-Fused Heterocycles with Trifluoromethyl Thianthrenium Triflate

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 journal of Chemistry 2024年第15期42卷 1679-1685页

作者： Chang ge Lipeng Qiao Yuyang Zhang Kai sun jangzhen An Mei Peng Xiaolan Chen Lingbo Qu Bing Yu College of Chemistry Zhengzhou UniversityZhengzhouHenan 450001China National engineering Research Center of Low-Carbon Processing and Utilization of Forest Biomass Nanjing Forestry UniversityNanjingJiangsu210037China school of Pharmacy Hengyang Medical SchoolUniversity of South ChinaHengyangHunan 421001China

A novel and eco-friendly electrochemical activation of trifluoromethyl thianthrenium triflate(TT-CF_(3)^(+)OTf^(-))for trifluoromethylation of imidazole-fused heteroaromatic compounds was *** method involves the direct electrolysis of TT-CF_(3)^(+)OTf^(-)without the requirement of external oxidants or catalysts,aligning with the principles of green chemistry.A wide range of imidazole-fused heteroaromatic compounds including imidazo[1,2-a]pyridines and benzo[d]imidazo[2,1-b]thiazoles have been successfully trifluoromethylated using this technique,exhibiting excellent compatibility with various functional groups and a broad substrate ***,the method's applicability for one-pot sequential reactions enables the reduction of waste and resource consumption by eliminating the need for intermediate purification steps.

关键词： Trifluoromethylation electrochemical Metal-free Imidazole-fused heterocycles Thianthrenium

eHMT2 promotes tumorigenesis in GNAQ/11-mutant uveal melanoma via ARHGAP29-mediated RhoA pathway

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Acta Pharmaceutica sinica B 2024年第3期14卷 1187-1203页

作者： Yongyun Li Tianyu Zhu jie Yang Qianqian Zhang shiqiong Xu shengfang ge Renbing jia jianming Zhang Xianqun Fan Department of Ophthalmology Ninth People’s HospitalShanghai Jiao Tong University School of MedicineShanghai 200001China shanghai Key Laboratory of Orbital Diseases and Ocular Oncology Shanghai 200001China National Research Center for Translational Medicine(shanghai) State Key Laboratory of Medical GenomicsShanghai Institute of HematologyRuijin HospitalShanghai Jiao Tong University School of MedicineShanghai 200025China Institute of Translational Medicine Zhangjiang Institute for Advanced StudyShanghai Jiao Tong UniversityShanghai 200240China

Constitutive activation of GNAQ/11 is the initiative oncogenic event in uveal melanoma(UM).Direct targeting GNAQ/11 has yet to be proven feasible as they are vital for a plethora of cellular *** search of genetic vulnerability for UM,we found that inhibition of euchromatic histone lysine methyltransferase 2(eHMT2)expression or activity significantly reduced the proliferation and migration capacity of cancer ***,elevated expression of eHMT2 had been validated in UM ***,Kaplan-Meier survival analysis indicated high eHMT2 protein level was related to poor recurrence-free survival and a more advanced T *** immunoprecipitation sequencing analysis and the following mechanistic investigation showed that ARHGAP29 was a downstream target of *** transcription was suppressed by eHMT2 in a methyltransferasedependent pattern in GNAQ/11-mutant UM cells,leading to elevated RhoA *** constitutively active RhoA in UM cells lacking eHMT2 restored oncogenic *** blocking eHMT2 and GNAQ/11 signaling in vitro and in vivo showed a synergistic effect on UM growth,suggesting the driver role of these two key *** summary,our study shows evidence for an epigenetic program of eHMT2 regulation that influences UM progression and indicates inhibiting eHMT2 and MeK/eRK simultaneously as a therapeutic strategy in GNAQ/11-mutant UM.

关键词： Uveal melanoma eHMT2 RhoA pathway ARHGAP29 G protein GNAQ GNA11

single-atom Pt on carbon nanotubes for selective electrocatalysis

在线全文

学校读者我要写书评

暂无评论

Carbon energy 2024年第1期6卷 63-71页

作者： samuel s.Hardisty Xiaoqian Lin Anthony R.j.Kucernak David Zitoun Department of Chemistry Bar Ilan Institute of Nanotechnology and Advanced Materials(BINA)Bar Ilan UniversityRamat GanIsrael Department of Chemistry Molecular Science Research HubImperial College LondonLondonUK

Utilizing supported single atoms as catalysts presents an opportunity to reduce the usage of critical raw materials such as platinum,which are essential for electrochemical reactions such as hydrogen oxidation reaction(HOR).Herein,we describe the synthesis of a Pt single electrocatalyst inside single-walled carbon nanotubes(sWCNTs)via a redox *** via electron microscopy,X-ray photoelectron microscopy,and X-ray absorption spectroscopy show the single-atom nature of the *** electrochemical behavior of the sample to hydrogen and oxygen was investigated using the advanced floating electrode technique,which minimizes mass transport limitations and gives a thorough insight into the activity of the *** single-atom samples showed higher HOR activity than state-of-the-art 30%Pt/C while almost no oxygen reduction reaction activity in the proton exchange membrane fuel cell operating *** selective activity toward HOR arose as the main fingerprint of the catalyst confinement in the sWCNTs.

关键词： confinement electrocatalysis hydrogen platinum single atom catalysts

Kriging-boosted CR modeling for prompt infill drilling optimization

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Petroleum 2024年第1期10卷 39-48页

作者： elizaveta s.Gladchenko Anna e.Gubanova Denis M.Orlov Dmitry A.Koroteev skolkovo Institute of science and Technology Russian Federation Digital Petroleum LLC Russian Federation

The capacitance-resistance model(CRM) has been a useful physics-based tool for obtaining production forecasts for decades. However, the model's limitations make it difficult to work with real field cases,where a lot of various events happen. such events often include new well commissioning(NWC). We introduce a workflow that combines CRM concepts and kriging into a single tool to handle these types of events during history matching. Moreover, it can be used for selecting a new well placement during infill drilling. To make the workflow even more versatile, an improved version of CRM was used. It takes into account wells shut-ins and performed workovers by additional adjustment of the model coefficients. By preliminary re-weighing and interpolating these coefficients using kriging, the coefficients for potential wells can be determined. The approach was validated using both synthetic and real datasets, from which the cases of putting new wells into operation were selected. The workflow allows a fast assessment of future well performance with a minimal set of reservoir data. This way, a lot of well placement scenarios can be considered, and the best ones could be chosen for more detailed studies.

关键词： Capacitance-resistance model (CRM) Field development optimization Infill drilling Interwell connectivity Kriging New well commissioning (NWC)

Investigation of the transformation of organic matter of carbonate deposits of the semiluksky-Mendymsky horizon under hydrothermal conditions

在线全文

学校读者我要写书评

暂无评论

Petroleum 2024年第2期10卷 216-223页

作者： s.M.Petrov A.I.Lakhova e.G.Moiseeva A.G.safiulina Institute of Petroleum Chemistry and Nanotechnologies Kazan National Research Technological University Institute of geology and Oil and Gas Technologies Kazan Federal University

The paper presents the results of studies on the transformation of the organic matter of siliceous-clayey carbonate rocks of the semiluksko-Mendymsky horizon of the Romashkino oil field in a hydrothermal fluid for an hour（with a water-to-rock ratio of 33） at 340℃ and 380℃ and pressu res of 17 and 20 *** a result of hydrothermal treatment,at 340℃ and 17 MPa,based on nitrogen porosimetry and electron microscopy data,transformations of rock-forming minerals in the rock are *** lead to an increase in the volume and average diameter of mesopores in it and the formation of micropores,as well,which improve its filtration *** the same time,the amount of kerogen in the composition of the organic matter decreases and the yield of the petroleum hydrocarbon extract increases,in which,according to the sARA analysis,the content of asphaltenes increases and the content of resins,aromatic and saturated hydrocarbons *** the composition of aroatic hydrocarbons,the proportion of a lkyltri methyl benzenes and dibenzothiophenes increases,phenanthrene homologues appear,and in the composition of saturated hydrocarbons,the amount of iso-structure alkanes decreases relative to the content of linear *** the temperature and pressure of the hydrothermal fluid to 380℃ and 20 MPa increases the degree of kerogen conversion from 12.4% to 23.6%.At the same time,changes occurring in the component composition of petroleum hydrocarbon extracts remains similar to the experiments carried out at 340℃ and 17 MPa;the content of naphthalenes decreases,the content of dibenzothiophenes increases and C11-C17,C19-C22alkyltrimethylbenzenes *** to IR spectroscopy,with increasing temperature and pressure of the hydrothermal fluid the intensity of the absorption bands of the aromatic ring,aliphatic fragments,and oxygen-containing groups increases in resins;the structural-group composition of asphaltenes changes little:aromaticity and the content of condensed

关键词： Carbonate deposits Organic matter Hydrothermal fluid Mobile hydrocarbons

Fascination For Planes Young Ghanaian pursues her aviation dream in China

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

ChinAfrica 2024年第5期16卷 54-55页

作者： ge LIjUN 不详

every morning at 7 o’clock,Rachael Amoah,a young woman from Ghana,prepares for a new day of challenges and innovations at a leading aerospace company in shanghai’s Pudong New *** March last year,she completed her studies in the school of Aeronautics and Astronautics at shanghai jiao Tong University(sjTU),and fulfilled her ambition to work in this megalopolis.

关键词： aviation dream pursue