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Open Journal of Polymer Chemistry 2022年第3期12卷 93-100页

作者： Ravindra v. gadhave Department of Polymer and Surface Engineering Institute of Chemical Technology Mumbai India

Conventionally available Polyvinyl acetate (PvAc) wood glues are polyvinyl alcohol (PvA) stabilized, with drawbacks like poor strength at high humidity, poor strength at high temperature and workability at low-temperature. PvAc is non-resistant to high humidity, and if such adhesive bonds are exploited in a highly humid environment, its strength substantially decreases. Sufficiently water-resistant adhesive bonds are achieved by modifying PvAc dispersion with special chemicals like acrylic acid (AA) and N-methylol acrylamide (NMA) as a co-monomer, Silanes, and ethylene modified PvA. The Lewis acids like aluminium chloride and aluminium nitrate are used as cross-linkers. So PvAc adhesives are classified as reactive and non-reactive glue. Application of non-reactive D1 (as per EN 204-205) and reactive D2 and D3 (as per EN 204-205) adhesives for bonding laminate on plywood is a regular practice in the Indian market. In summer time, Crack formation was seen in laminate bonded with reactive D2 and D3 adhesives in regions where the room temperature was above 45°C. However, if the same laminate substrates were bonded with non-reactive D1, no cracks were seen. To analyse the above phenomenon, we have done Dynamic mechanical analysis of non-reactive D1, reactive D2 and D3 adhesive.

关键词： Polyvinyl Acetate Wood Adhesive Cracking Dynamic Mechanical Analysis

Al-driven peculiarities of local coordination and magnetic properties in single-phase Al_(x)-CrFeCoNi high-entropy alloys

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Nano Research 2022年第6期15卷 4845-4858页

作者： Alevtina Smekhova Alexei Kuzmin Konrad Siemensmeyer Chen Luo Kai Chen Florin Radu Eugen Weschke Uwe Reinholz Ana guilherme Buzanich Kirill v.Yusenko Helmholtz-Zentrum Berlin für Materialien und Energie(HZB) D-12489Germany Institute of Solid State Physics University of LatviaLV-1063Latvia Bundesanstalt für Materialforschung und-prüfung(BAM) D-12489Germany

Modern design of superior multi-functional alloys composed of several principal components requires in-depth studies of their local structure for developing desired macroscopic ***,peculiarities of atomic arrangements on the local scale and electronic states of constituent elements in the single-phase face-centered cubic(fcc)-and body-centered cubic(bcc)-structured high-entropy Alx-CrFeCoNi alloys(x=0.3 and 3,respectively)are explored by element-specific X-ray absorption spectroscopy in hard and soft X-ray energy *** based on the reverse Monte Carlo approach allow to perform a simultaneous fit of extended X-ray absorption fine structure spectra recorded at K absorption edges of each 3d constituent and to reconstruct the local environment within the first coordination shells of absorbers with high *** revealed unimodal and bimodal distributions of all five elements are in agreement with structure-dependent magnetic properties of studied alloys probed by magnetometry.A degree of surface atoms oxidation uncovered by soft X-rays suggests different kinetics of oxide formation for each type of constituents and has to be taken into account.X-ray magnetic circular dichroism technique employed at L2,3 absorption edges of transition metals demonstrates reduced magnetic moments of 3d metal constituents in the sub-surface region of in situ cleaned fcc-structured Al0.3-CrFeCoNi compared to their bulk *** to nanostructured versions of multicomponent alloys,such studies would bring new insights related to effects of high entropy mixing on low dimensions.

关键词： high-entropy alloys reverse Monte Carlo magnetism element-specific spectroscopy extended X-ray absorption fine structure(EXAFS) X-ray magnetic circular dichroism(XMCD)

Mucinous cystadenoma of the appendix associated with adenocarcinoma of the sigmoid colon and hepatocellular carcinoma of the liver:Report of a case

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World Journal of gastroenterology 2006年第12期12卷 1975-1977页

作者： Srdjan P Djuranovic Milan M Spuran Nada v Kovacevic Milenko B Uqliesic Dragutin M Kecmanovic Marian T Micev Institute for Digestive Diseases Clinical Center of SerbiaK.Todorovica St No 611000 BelgradeSerbia and Montenegro

Mucinous cystadenoma of the appendix is a rare condition and represents one of the three entities with the common name mucocele of the appendix. It is characterized by a cystic dilatation of the lumen with stasis of mucus inside it. Histopathologically mucocele is divided into three groups： focal or diffuse mucosal hyperplasia, mucinous cystadenoma and mucinous cystadenocarcinoma. This condition is often associated with other neoplasia, especially adenocarcinoma of the colon and ovaries. We here describe a 57 year old male patient who presented with abdominal discomfort, constipation, fresh blood in stool and frequent urination. He had a big cystadenoma of the appendix associated with adenocarcinoma of the colon and hepatocellular carcinoma of the liver. The patient underwent right haemicolectomy, sigmoid colon resection and segmental resection of the liven Now 3 years later he has no evidence of disease relapse. According to this, we stress the need of accurate preoperative diagnosis and intraoperative exploration of the whole abdomen in these patients.

关键词： Hucocele Appendiceal cystadenoma Colon carcinoma Hepatocellular carcinoma

CaAl_(2)Si_(2)O_(8) polymorphs:Sensitive geothermometers and geospeedometers

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geoscience Frontiers 2023年第1期14卷 33-45页

作者： Liudmila A.gorelova Oleg S.vereshchagin vladimir N.Bocharov Sergey v.Krivovichev Andrey A.Zolotarev Mikhail A.Rassomakhin Institute of Earth Sciences Saint Petersburg State UniversitySt.PetersburgRussia Centrefor geo-Environmental Research and Modelling(geomodel).Saint Petersburg State University St.PetersburgRussia Kola Science Centre ApatityMurmansk RegionRussia South Urals Federal Research Center of Mineralogy and geoecology of UB RAS MiassRussia

Plagioclase is the major rock-forming mineral constituting the Earth's crust,whereas anorthite(CaAl_(2)Si_(2)O_(8))is a common minerals in lunar highlands crust,meteorites,possibly in some comets and on *** anorthite,two high-temperature polymorphs of CaAl_(2)Si_(2)O_(8)are known:dmisteinbergite and svyatoslavite,which are found in burnt coal dumps,meteorites and *** we present the results of detailed studies(quenching experiments,elemental analysis,Raman spectroscopy and in situ high temperature single crystal X-ray diffraction(up to 1000℃))on naturally co-occurring CaAl_(2)Si_(2)O_(8)polymorphs(anorthite,dmisteinbergite and svyatoslavite)from a burnt coal dump in Kopeisk,*** polymorphs were found in all natural samples and obtained upon heating of dmisteinbergite(unquenchableβ-dmisteinbergite and quenchable y-dmisteinbergite).It was shown that Ca coordination differs significantly in CaAl_(2)Si_(2)O_(8)polymorphs,resulting in a different capacity to host Ba and possibly other large ion lithophile *** our data on natural samples with the previously published data on natural and synthetic compounds,we propose a new scheme of CaAl_(2)Si_(2)O_(8)polymorphs *** results indicate that CaAl_(2)Si_(2)O_(8)polymorphs could be used for temperature estimations for both Earth and planetary sciences.

关键词： Feldspar Polymorphism Anorthite Dmisteinbergite Svyatoslavite CaAl_(2)Si_(2)O_(8)

苏联v.A.奥勃鲁契夫对中国西北地区地质调查的贡献

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河北地质大学学报 1992年第5期 546-549页

作者： v.v.Tikhomirov 刘亚民苏联莫斯科科学院通讯院士、国际地质科学史委员会副主席

v.A.奥勃鲁契夫是19世纪俄国的著名地质和地貌学家。他曾几次(1880,1892—1894,1905—1906)来到中国东北、西北地区考察,著述甚多。对中国的地质和地貌学研究,特别是论述了中国黄土分布与成因方面做出了贡献。本文主要记述了他在1892—1... 详细信息

v.A.奥勃鲁契夫是19世纪俄国的著名地质和地貌学家。他曾几次(1880,1892—1894,1905—1906)来到中国东北、西北地区考察,著述甚多。对中国的地质和地貌学研究,特别是论述了中国黄土分布与成因方面做出了贡献。本文主要记述了他在1892—1894年来中国西北部地区考察的情况,并把要阐述他这次考察的学术成果。

关键词：准噶尔绰罗斯部地质调查 v.A 鄂尔多斯山系海平面湖相陆相中华人民共和国山脉南山第三纪李希霍芬地貌学地形学褶皱系苏联苏维埃社会主义共和国联盟

Highly graphitized carbon nanosheets with embedded Ni nanocrystals as anode for Li-ion batteries

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Nano Research 2020年第1期13卷 86-94页

作者： Francisco Javier Soler-Piña Celia Hernández-Rentero Alvaro Caballero Julián Morales Enrique Rodríguez-Castellón Jesús Canales-vázquez Dpto.Química Inorgánica e Ingeniería Química Instituto de Química Fina y NanoquímicaUniversidad de Córdoba14071CórdobaSpain Dpto.Química Inorgánica Cristalografía y MineralogíaFacultad de CienciasUniversidad de Málaga29071MálagaSpain Instituto de Energías Renovables Universidad de Castilla-La ManchaPaseo de La Investigación 102071AlbaceteSpain

A C/Ni composite was prepared via thermal decomposition of a nickel oleate complex at 700℃,yielding disperse Ni nanocrystals with an average size of 20 nm,encapsulated by carbon nanosheets as deduced from transmission electron microscopy(TEM)images and confirmed from X-ray photoelectron spectroscopy(XPS).Furthermore,the X-ray diffraction pattern revealed a good ordering of the carbon layers,forced by the Ni encapsulation to adopt a bending *** the close interaction between the graphitized framework and the metallic nanoparticles we have studied the properties of the composite as an anode for Li-ion *** with other nanostructured synthetic carbons,this carbon composite has a low voltage hysteresis and a modest irreversible capacity value,properties that play a significant role in its behaviour as electrodes in full cell *** moderate rate values,0.25 C,the electrode delivers an average capacity value around 723 mAh·g^−1 on cycling,among the highest values so far reported for this carbon *** higher rate values,1 C,the average capacity values delivered by the cell on cycling decrease,around 205 mAh·g^−1,but it maintains good capacity retention,a coulombic efficiency close to 100%after the first cycles and recovery of the capacity values when the rate is restored from 3 to 0.1 C.

关键词： carbon nanosheets nickel nanoparticles anode lithium batteries

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羊针麻剖腹产一例

中兽医学杂志 1985年第4期 49-50页

作者： g.v.Lakshmipathi 葛颐昌

使用某些相当于牛的 BL—30(百环俞)gov—20(百会)、天平,犬的 ST—36(足三里)的针刺麻醉穴位,在电针麻醉下成功地施行羊剖腹产术一例,以讨论针麻的镇痛效应,并提出充分研究绵羊针麻实用的可能性。

关键词：剖腹产术穴位绵羊电针剖宫产术针麻针刺麻醉感觉障碍痛觉缺失

The challenge of hepatic vein reconstruction in surgical oncology

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Hepatobiliary Surgery and Nutrition 2022年第3期11卷 473-476页

作者： víctor Lopez-Lopez David Ferreras Dilmurodjon Eshmuminov Roberto Brusadin Ricardo Robles-Campos Department of general Visceral and Transplantation SurgeryClinic and University Hospital Virgen de La ArrixacaIMIB-ARRIXACAEl PalmarMurciaSpain Department of Surgery and Transplantation Swiss Hepato-Pancreato-Biliary(HPB)CenterUniversity Hospital ZurichZurichSwitzerland

In the liver surgical oncology,a complete resection of the primary or metastatic liver tumors remains the main *** the tumor invades the hepatic vein or the inferior vena cava(IvC)a curative resection becomes ***,recent advances in intraoperative hemodynamic management together with the refinement of the surgical technique acquired by complex liver surgery and transplantation have allowed to perform hepatic vein or vena cava resection for curation with low morbidity and mortality.

关键词： surgical hepatic mortality

Morphology,structure and magnetic behavior of orthorhombic and hexagonal HoFeO_(3)synthesized via solution combustion approach

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Journal of Rare Earths 2022年第2期40卷 296-301,I0004页

作者： K.D.Martinson I.S.Kondrashkova M.I.Chebanenko A.S.Kiselev T.Yu Kiseleva v.I.Popkov Ioffe Institute 26 PoliteknicheskayaSL Petersburg194021Russia Saint Petersburg State Institute of Technology 26 MoskovskySt.Petersburg190013Russia Faculty of Physics M.V.Lomonosov State UniversityLeninskie CoryMoscow119991Russia

Nanostructured HoFeO_(3)powders were obtained by solution combustion method at various glycinenitrate ratios(g/N=0.2,0.4,...,1.4).According to X-ray powder diffractometry data,the presence of two modifications of HoFeO_(3)in the synthesized samples was established:orthorhombic(Pbnm)and hexagonal(P63/mmc).The crystallite size of the obtained compositions varies from 62±6 to 29±3 nm,depending on the g/N *** magnetic structure studies,it is found that HoFeO_(3)obtained with a stoichiometric amount of glycine in the reaction solution is in the magnetically ordered state and is represented by a sextet with quadrupole splitting(QS)=0 mm/s,isomeric shift(IS)=0.36 mm/s and effective field strength(Heff)=497 *** to the results of vibrational magnetometry,it is found that the orthoferrites obtained have a ferromagnetic structure,the main parameters of which(Ms,Mr and Hc)systematically change with a change in the redox ratio of the reaction mixture and,as a consequence,their phase composition,and reach maximum values at a g/N ratio=*** the samples obtained with a significant excess and lack of glycine(g/N=0.2 and 1.4),despite their amorphous nature,hysteresis loops characteristic of the ferromagnetic state of the substance is *** is hopeful to obtain a pure hexagonal modification of HoFeO_(3)via heat treatment on amorphous products of glycine-nitrate combustion.

关键词： Crystal structure Rare earth compounds Perovskites Nanomaterials Magnetic materials

Electrodynamics in Curvilinear Coordinates and the Equation of a geodesic Line

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Journal of Modern Physics 2022年第11期13卷 1382-1402页

作者： Anatoly v. Parfyonov Ulyanovsk State Technical University Ulyanovsk Russia

The creation of the theory of relativity, which discovered the equivalence of mass and energy, showed that the concept of a point charge, used in the formulation of Coulomb’s law, one of the basic laws of classical electrodynamics, contradicts the famous formula establishing the equivalence of mass and energy. But the discovery of quarks makes it possible to present classical electrodynamics in a form free from the indicated contradiction. In the article, having considered the electromagnetic field in a curvilinear coordinate system, a theory has been created that expands our understanding of the electromagnetic field, the nature of quarks, the nature of strong interaction, and the connection between strong interaction and electromagnetic interaction. This theory is based on the principle of equivalence of an electromagnetic field to a free material particle formulated in the article and the law of formation of elementary particles from an electromagnetic field that follows from it.

关键词： Electrodynamics Electromagnetic Field Curvilinear Coordinates Quarks Strong Interaction Equation of a geodesic Line