检索结果-南通市图书馆

Trapping the Short-Chain Odd Carbon Number Olefins Using Nickel(Ⅱ)-Catalyzed Tandem Ethylene Oligomerization and Friedel-Crafts Alkylation of Toluene

引用

Chinese Journal of Chemistry 2023年第21期41卷 2855-2865页

作者： sergey v.zubkevich vladislav A.Tuskaev Svetlana Ch.Gagieva Alexander A.Pavlov victor N.Khrustalev Fei Wang Li Pan Yuesheng Li Daniele Saracheno Anton A.vikhrov Dmitry N.Zarubin Boris M.Bulychev Department of Chemistry Lomonosov Moscow State UniversityLeninskie Gory 1Moscow119991 Russian Federation Materials Research and Technology Department Luxembourg Institute of Science and Technology5Avenue des Hauts-FourneauxL-4362 Esch-sur-AlzetteLuxembourg A N Nesmeyanov Institute of Organoelement Compounds Russian Academy of SciencesVavilova st.28Moscow119991 Russian Federation BMSTU Center of National Technological Initiative“Digital Material Science:New Material and Substances” Bauman MoscowState Technical University2nd Baumanskaya st.5MoscowRussian Federation Peoples’Friendship University of Russia(RUDN University) Miklukho-Maklay St.6Moscow117198 Russian Federation Zelinsky Institute of Organic Chemistry Russian Academy of SciencesLeninsky Prospekt 47Moscow119991 Russian Federation Institute of Advanced Polymer Materials School of Materials Science and EngineeringTianjin UniversityTianjin300350 China

Nickel(Ⅱ)complexes with pyrazole-based ligands are widely employed in catalysis of ethylene oligomerization and subsequent Friedel-Crafts alkylation of *** have prepared ten new nickel(Ⅱ)dibromide complexes with various substituted bis(azolyl)*** have been characterized using^(1)H NMR,IR,high resolution mass spectrometry and elemental *** structures of three complexes have been unambiguously established using X-ray *** was found that these complexes in the presence of Et2AlCl or Et_(3)Al_(2)Cl_(3)are active both in ethylene oligomerization and Friedel-Crafts alkylation processes(activity up to 3720 kgoligomer·mol[Ni]^(−1)·h^(−1)).The use of Et_(3)Al_(2)Cl_(3)results in a higher share of alkylated products(up to 60%).Moreover,catalytic systems activated with Et_(3)Al_(2)Cl_(3)produced small amounts of odd carbon number olefins(up to 0.8%).The Friedel-Crafts alkylation was used as a trap for previously undetected short-chain odd carbon number olefins(C_(3)and C_(5)).

关键词： Ethylene oligomerization Friedel-Crafts alkylation Nickel(Ⅱ)complexes N-ligands Odd carbon number olefins

来源：

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

Binuclear and Hexanuclear Ti(Ⅳ) Complexes Supported by [OOOO]^(4–)-type Ligand for Preparing Disentangled UHMWPE

引用

Chinese Journal of Polymer Science 2019年第5期37卷 471-477页

作者： vladislav A.Tuskaev Svetlana Ch.Gagieva Dmitry A.Kurmaev viktor G.vasil'ev Nikolay A.Kolosov sergey v.zubkevich Elena S.Mikhaylik Evgenii K.Golubev Galina G.Nikiforova Pavel A.Zhizhko Olga A.Serenko Boris M.Bulychev Department of Chemistry M.V.Lomonosov Moscow State University A.N.Nesmeyanov Institute of Organoelement Compounds Russian Academy of Sciences Enikolopov Institute of Synthetic Polymer Materials Russian Academy of Sciences

Binuclear and hexanuclear titanium complexes stabilized by tetradentate [OOOO]^(4–)-type ligand were active in ethylene polymerization in the presence of Et2 AlCl/Bu2 Mg binary co-catalyst, giving high molecular weight polyethylene. The binuclear complex showed significantly higher catalytic activity and thermal stability in comparison to mononuclear analogue. Ultra high molecular weight polyethylene(UHMWPE) samples were processed by a solid-state uniaxial deformation into high-strength(up to 2.5 GPa) and highmodulus(over 100 GPa) oriented film tapes, which indirectly indicates a low degree of entanglements between the macromolecular chains.

关键词： Binuclear catalysts Titanium Ethylene Ziegler-Natta polymerization UHMWPE

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Photoluminescence,structural and antibacterial properties of co-dopedβ-Ca_(3)(PO_(4))_(2)-type phosphates Ca_(8)CuRE(PO_(4))_(7)(RE=Eu-Er)

引用

Journal of Rare Earths 2024年第9期42卷 1658-1668,I0002页

作者： Ivan v.Nikiforov Ekaterina v.Iliin Bogdan I.Lazoryak sergey M.Aksenov Pavel v.Slukin Dina v.Deyneko Department of Chemistry Lomonosov Moscow State University119991MoscowRussia Laboratory of Arctic Mineralogy and Material Sciences Kola Science CentreRussian Academy of Sciences184209ApatityRussia Geological Institute Kola Science CentreRussian Academy of Sciences184209ApatityRussia State Scientific Center of Applied Microbiology and Biotechnology of Rospotrebnadzor 24 Block A142279ObolenskRussia

Novel Ca_(8)CuRE(PO_(4))_(7)where RE^(3+)=Eu^(3+),Tb^(3+),Dy^(3+),Ho^(3+)and Er^(3+)were synthesized by a solid-state method in *** structures of the samples were characterized by powder X-ray diffraction using Rietveld refinement to determine the occupation of crystal *** samples are found to have a centrosymmetric structure with space group R3c,as shown by dielectric *** synthesized Ca_(8)CuRE(PO_(4))_(7)samples have multifunctional *** Cu^(2+)ions provide antibacterial properties,while the rare earth elements ions exhibit luminescence properties,and theβ-Ca_3(PO_(4))_(2)-type host is *** photoluminescence properties of RE^(3+)ions were studied and compared with other simmilar Ca_(8)MRE(PO_(4))_(7)phosphates,where M is a divalent *** photoluminescence intensity quenching in terms of energy transfer from RE^(3+)to Cu^(2+)is *** bioactive properties were studied in relation to antibacterial activity against *** and *** syntesized Ca_(8)CuRE(PO_(4))_(7)samples demonstrate very high and stable inhibition of bacteria *** correlation between crystal structure and properties is *** combining multiple approaches to the directio nal design of such materials,several important properties within a single chemical compound to achieve biovisualization and bioactive properties simultaneously can be combined.

关键词： β-Ca_(3)(PO_(4))_(2) Whitlockite-type structure Bioactive phosphates TCP Photoluminescence Rare earths

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Selection of shaped charges parameters for producing aluminum particles with velocities in the range of 2.5-16 km/s

引用

Defence Technology（防务技术） 2024年第8期38卷 126-135页

作者： vladimir I.Kolpakov sergey v.Fedorov Ekaterina P.vinogradova Irina A.Bolotina Bauman Moscow State Technical University Moscow 105005Russia

Testing rocket and space technology objects in ground conditions for resistance to the impact of meteoroids and fragments of space debris can be carried out using shaped charges. To substantiate the design parameters of shaped charges that ensure the formation of aluminum particles in a wide velocity range(from 2.5 to 16 km/s), numerical modeling of the formation process was carried out within the framework of a two-dimensional axisymmetric problem of continuum mechanics using three different computing codes to increase the reliability of the results. The calculations consider shaped charges with a diameter of 20-100 mm with aluminum liners of various shapes. It is shown that the formation of particles with velocities close to the lower limit of the considered range is ensured by gently sloping segmental liners of degressive thickness. To form higher-velocity particles with velocities over 5 km/s, it is proposed to use combined liners, the jet-forming part of which has the shape of a hemisphere of constant thickness or the shape of a semi-ellipsoid or semi-superellipsoid of rotation of degressive thickness.

关键词： Space debris Meteoric impact Explosion Shaped charge High-velocity aluminum element Segmental liner Combined liner Numerical simulation

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Early selective enteral feeding in treatment of acute pancreatitis: A case report

引用

World Journal of Clinical Cases 2024年第3期12卷 637-642页

作者： Aleksei A Kashintsev sergey v Anisimov Anastasya Nadeeva vitali Proutski sergey v Anisimov Anastasya NadeevaVitali ProutskiPANDICA LTDLondon WC1N 3ESUnited Kingdom

BACKGROUND Early initiation of enteral feeding is recognized to play a crucial role in improving the outcomes of treatment of acute ***,the method of adminis-tration of enteral nutrition remains *** present the experience of treating a patient with moderate-severe acute pancreatitis,at high risk of progressing to a severe or fatal condition,using a novel method of selective feeding with duodenal *** SUMMARY A 27-year-old female patient presented to the emergency unit of the hospital with a typical manifestation of acute *** a conventional treatment,the patient’s condition deteriorated by day 2 of *** an endoscopic approach,a novel catheter PandiCathffwas placed to the duodenum of the patient,isolating its segment between the duodenal bulb and the ligament of *** the isolated area created,a negative pressure was applied,followed by introduction of early selective enteral *** patient’s condition subsequently improved in a rapid manner,and no complications often associated with moderate-to-severe acute pancreatitis *** Within 48 h of starting treatment with the novel method,it can prevent the development of multiple organ failure and,when combined with minimally invasive drainage methods,help prevent infection.

关键词： Acute pancreatitis Enteral feeding Infectious complications Systemic inflammatory response syndrome MODS

来源：

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

Ballistic performance of titanium-based layered composites made using blended elemental powder metallurgy and hot isostatic pressing

引用

DEFENCE TECHNOLOGY 2024年第9期39卷 1-14页

作者： Markovsky, Pavlo Janiszewski, Jacek Savvakin, Dmytro Stasyuk, Oleksandr Fikus, Bartosz Samarov, victor Ellison, vianey Prikhodko, sergey, v NAS Ukraine GV Kurdyumov Inst Met Phys 36Academician Vernadsky Blvd UA-03142 Kyiv Ukraine Jaroslaw Dabrowski Mil Univ Technol 2Gen Sylwester Kaliski Str PL-00908 Warsaw 46 Poland Synertech Inc 11711 Monarch St Garden Grove Los Angeles CA 92841 USA Univ Calif Los Angeles Dept Mat Sci & Engn Los Angeles CA 90095 USA

Metal matrix composites tiles based on Ti-6Al-4v (Ti64) alloy, reinforced with 10, 20, and 40 (vol%) of either TiC or TiB particles were made using press-and-sinter blended elemental powder metallurgy (BEPM) and then bonded together into 3-layer laminated plates using hot isostatic pressing (HIP). The laminates were ballistically tested and demonstrated superior performance. The microstructure and properties of the laminates were analyzed to determine the effect of the BEPM and HIP processing on the ballistic properties of the layered plates. The effect of porosity in sintered composites on further diffusion bonding of the plates during HIP is analyzed to understand the bonding features at the interfaces between different adjacent layers in the laminate. Exceptional ballistic performance of fabricated structures was explained by a significant reduction in the residual porosity of the BEPM products by their additional processing using HIP, which provides an unprecedented increase in the hardness of the layered composites. It is argued that the combination of the used two technologies, BEPM and HIP is principally complimentary for the materials in question with the abilities to solve the essential problems of each used individually.

关键词： Metal matrix composites Powder metallurgy Titanium hydride powder Master alloy Titanium carbide Titanium boride Hot isostatic pressing Ballistic tests TI-6AL-4v ALLOY TIB COMPOSITES ARMOR STEELS BEHAvIOR MICROSTRUCTURE PROJECTILES AEROSPACE

来源：

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

Interaction of edge dislocations with voids in tungsten

引用

Tungsten 2024年第3期6卷 633-646页

作者： Arseny Kazakov Rita I.Babicheva Aleksandr Zinovev Dmitry Terentyev Kun Zhou Elena A.Korznikova sergey v.Dmitriev Research Laboratory for Metals and Alloys under Extreme Impacts Ufa University of Science and Technology Institute for Metals Superplasticity Problems of RAS School of Mechanical and Aerospace Engineering Nanyang Technological University Institute for Nuclear Energy Technology Belgian Nuclear Research Center Technological Machines and Equipment Department Ufa State Petroleum Technological University Institute of Mechanical Science Problems of RAS Institute of Molecule and Crystal Physics UFRC of Russian Academy of Sciences

Tungsten is widely used as a material capable of withstanding extreme operating conditions and is one of the candidates for use in fusion and Generation Ⅳ fission *** modelling implemented to solve various material science problems is an indispensable approach for improving material *** work analyzes the interaction of an edge dislocation with a void in single-crystal tungsten with the help of molecular dynamics *** different approaches for studying the dynamics of dislocations in tungsten that differ in boundary conditions are *** interactions of the dislocation and void at different temperatures are investigated,and based on the obtained stress-strain curves,the dislocation obstacle strength for voids having various diameters is *** is shown that when applied to a crystal with small voids,the model with the fixed boundary conditions returns incorrect ***,the influence of the cell size for the model with periodic boundary conditions is analyzed,and the case of a non-central interaction of a dislocation with a void is *** obtained results improve our understanding of the mechanical response of irradiated materials.

关键词： Tungsten Molecular dynamics method Dislocations voids Boundary conditions

来源：

同方期刊数据库评论

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Porous Shish-Kebab Structure Prepared from Oriented UHMWPE Films by Processing in Supercritical CO_(2)

引用

Chinese Journal of Polymer Science 2024年第1期42卷 97-104,I0009页

作者： sergey A.Lermontov Aleksey v.Maksimkin Nataliya A.Sipyagina Tarek Dayyoub Alena N.Malkova Evgeniy A.Kolesnikov Elena A.Straumal Inna O.Gozhikova Saidkhodzha G.Nematulloev Dmitry v.Telyshev Institute of Physiologically Active Compounds of the Russian Academy of Sciences Chernogolovka 142432Russia Institute for Bionic Technologies and Engineering I.M.Sechenov First Moscow State Medical University(Sechenov University)Moscow 19991Russia National University of Science and Technology"MISIS"Moscow 119049 Russia Institute of Biomedical Systems National Research University of Electronic TechnologyZelenogradMoscow 124498Russia

For the first time, a highly crystalline porous shish-kebab structure with a high degree of crystallinity was obtained by using a combination of two methods for the formation of porous polymeric materials. A treatment procedure using supercritical carbon dioxide(sc CO_(2))was carried out for oriented ultrahigh molecular weight polyethylene(UHMWPE) films, which provided special conditions for the crystallization of dissolved UHMWPE macromolecules on the surface of oriented UHMWPE crystals. The prepared porous materials were investigated by scanning electron microscopy(SEM) and differential scanning calorimetry(DSC). The particularity of the obtained porous shish-kebab is the absence of the amorphous phase between lamellar crystals(kebabs). The obtained pores had an oval shape, and they were oriented in the orientation direction of the UHMWPE macromolecules. The pore size ranged from 0.05 μm to 4 μm. Controlling the conditions for the crystallization of the UHMWPE macromolecules using supercritical CO_(2) gives the possibility to control the size of both lamellar disks and pores formed.

关键词： UHMWPE Supercritical CO_(2) Porous shish-kebab structure

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

The effect of long-term application of nitrogen-rich fertilizers on soil resistome:A study of conventional and organic cropping systems

引用

Soil Ecology Letters 2024年第3期6卷 135-150页

作者： Alexey S.vasilchenko Evgenii O.Burlakov Darya v.Poshvina Denis S.Gruzdev sergey v.Kravchenko Aleksandr v.Iashnikov Ning Ling Anastasia v.vasilchenko Laboratory of Antimicrobial Resistance Institute of Environmental and Agricultural Biology(X-BIO)Tyumen State UniversityTyumenRussia Research Institute of Mathematics Physics and Computer ScienceDerzhavin Tambov State UniversityTambovRussia International Integrated Research Laboratory for Climate Change Land Use and BiodiversityInstitute of Environmental and Agricultural Biology(X-BIO)Tyumen State UniversityTyumenRussia SciBear OU Tartu Mnt 67/1-13bKesklinna Linnaosa10115 TallinnEstonia Center for Grassland Microbiome State Key Laboratory of Grassland Agro-EcosystemsCollege of Pastoral Agriculture Science and TechnologyLanzhou UniversityLanzhou 730000China

Metagenomic studies of various soil environments have previously revealed the widespread distribution of antibiotic resistance genes(ARGs)around the *** this study,we applied shotgun metagenomics to investigate differences in microbial communities and resistomes in Chernozem soils that have been under long-term organic and conventional cropping *** organic cropping system was seeded with Triticum spelta without any *** conventional cropping system was seeded with Tríticum durum Desf and used mineral fertilizer(NPK),that resulted in an increased amount of total and available carbon and nitrogen in *** all samples,we identified a total of 21 ARG classes,among which the dominant were vancomycin,tetracycline and *** of soil microbial communities revealed differences between the studied fields in the relative abundances of 14 and 53 genera in topsoil and subsoil,*** analysis showed significant correlations(positive and negative)among 18 genera and 6 ARGs,as well as between these ARGs and some chemical properties of *** analysis of metagenome-assembled genomes revealed that Nitrospirota,Thermoproteota,Actinobacteriota and Binatota phyla of archaea and bacteria serve as hosts for glycopeptide and fluoroquinolone/tetracycline ***,the data obtained enrich knowledge about the consequences of human agricultural activities in terms of soil microbiome modification and highlight the role of nitrogen cycling taxa,including uncultivated genera,in the formation of soil resistome.

关键词： soil microbiome inorganic fertilizer nitrogen cycle uncultured bacteria chemolithotrophs Binatia

来源：

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

Investigation of WZ Sge-type Dwarf Nova ASASSN-19oc:Optical Spectroscopy and Multicolor Light Curve Analysis

引用

Research in Astronomy and Astrophysics 2024年第8期24卷 20-31页

作者： viktoriia Krushevska sergey Shugarov Paolo Ochner Yuliana Kuznyetsova Mykola Petrov Peter Kroll Astronomical Institute of the Slovak Academy of Sciences Tatranska Lomnica05960 VysokéTatrySlovakia Main Astronomical Observatory of NAS of Ukraine 27 Akademika Zabolotnoho St.03143 KyivUkraine INAF—Osservatorio Astronomico di Padova Vicolo dell’Osservatorio 5I-35122 PadovaItaly Department of Physics and Astronomy University of PadovaVia F.Marzolo 8I-35131 PadovaItaly Max Planck Computing and Data Facility(MPCDF) Gießenbachstrasse 2D-85748 GarchingGermany Sonneberg Observatory Sternwartestr.32D-96515 SonnebergGermany

In this study,we present an investigation of the newly discovered dwarf nova ASASSN-19oc during its superoutburst on 2019 June *** carried out detailed UBvRcIc-photometric observations and also obtained a spectrum on day 7 of the outburst,which shows the presence of hydrogen absorption lines commonly found in dwarf nova *** of photometric data reveals the occurrence of early superhumps in the initial days of observations,followed by ordinary and late *** have accurately calculated the period of the ordinary superhumps as Pord=0.05681(10)days and determined the periods at different stages,as well as the rate of change of the superhump period(P_(dot)=(5)P/P=8.1×10^(-5)).Additionally,we have derived the mass ratio of the components(q=0.09),and estimated the color temperature during the outburst as~11,000 K,the distance to the system(d=560 pc)and absolute magnitude of the system in outburst(Mv=5.3).We have shown that outbursts of this star are very rare:based on brightness measurements on 600 archival photographic plates,we found only one outburst that occurred in *** fact,as well as the properties listed above,convincingly shows that the variable ASASSN-19oc is a dwarf nova of WZ Sge type.

关键词： (stars)binaries(including multiple) close-(stars)novae-cataclysmic variables-stars dwarf novae

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：