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游離基聚合反應的新成就

高分子学报 1957年第3期 142-152页

作者： J.c.Bevingto ,h.W.Melville ,胡亞東

在這篇文章中要討論以游離基引發的聚合反應研究工作中的新成就。這篇文章是由四個部分組成的,相當於四個方向,在這些研究方向中近五、六年來達到了相當程度的進展。第一部分是關於在一般聚合過程中一些基本反應步驟的詳細歷程;也包括... 详细信息

在這篇文章中要討論以游離基引發的聚合反應研究工作中的新成就。這篇文章是由四個部分組成的,相當於四個方向,在這些研究方向中近五、六年來達到了相當程度的進展。第一部分是關於在一般聚合過程中一些基本反應步驟的詳細歷程;也包括用標記原子的研究工作。第二部分討论在聚合反應後一階段中的研究結果。這些研究工作對於高分子化合物工业生產具有极其重要的意義,同時也具有很大的理論兴趣,因為這些研究工作發現了那些

关键词：研究工作程中

Formation of β' phase in LPSO structures in an Mg88co5Y7 alloy

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Journal of Magnesium and Alloys 2022年第1期10卷 175-182页

作者： Q.Q.Jin X.h.Shao Y.T.Zhou B.Zhang S.J.Zheng X.L.Ma Shenyang National Laboratory for Materials Science Institute of Metal ResearchChinese Academy of Sciences72 Wenhua Road110016 ShenyangChina Materials Science and Engineering Research center Guangxi University of Science and TechnologyLiuzhou 545006China School of Materials Science and Engineering Research Institute for Energy Equipment MaterialsHebei University of TechnologyTianjin 300130China

Formation of β’ phase in long-period stacking ordered(LPSO) structures in an Mg;co;Y;(at.%) alloy after aging at 200 °c for 24 h or electron beam(EB) irradiation has been studied by high-angle annular dark-field scanning transmission electron microscopy(hAADFSTEM). β’ phase was precipitated only in the Mg matrix but not in LPSO structures after aging at 200 °c for 24 h. LPSO structure containing stacking defects transforms into the β’-long phase during EB irradiation, which plays a key role in accelerating solute atoms’ diffusion. New complex β’(LPSO) structures formed in the alloy after EB irradiation, such as β’(12 h) structure with an orthorhombic lattice(Mg;Y, cmcm,a = 2 _(a0)= 0.642 nm, b=4√3_(a0), c = 6 _(c0)= 3.12 nm).

关键词： Magnesium alloys Long-period stacking ordered(LPSO)structure hAADF-STEM β’phase

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Direct observation of the cO_(2) formation and c–h consumption of carbon electrode in an aqueous neutral electrolyte supercapacitor by in-situ FTIR and Raman

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Journal of Energy chemistry 2022年第8期31卷 488-496,I0013页

作者： Murilo M.Amaral Victor Y.Yukuhiro Rafael Vicentini Alfredo c.Peterlevitz Leonardo M.Da Silva pablo Fernandez hudson Zanin Advanced Energy Storage Division State University of Campinas13083-852Av.Albert Einsten 400CampinasSPBrazil chemistry Institute State University of Campinas13083-970Josue de Castro StreetCampinasSPBrazil Department of chemistry Laboratory of Fundamental and Applied ElectrochemistryFederal University of Jequitinhonha and Mucuri’s ValleyRodovia MGT 367km 5835000Alto da Jacuba39100-000DiamantinaMGBrazil center for Innovation on New Energies University of Campinas13083-841 CampinasSão PauloBrazil

Electrical double-layer capacitors(EDLcs)consist of energy storage devices that present high-power and moderate energy *** electrolyte and electrode physicochemical properties are crucial for improving their overall energy storage ***,the stability of the EDLcs’materials is the primary focus of this *** energy storage depends on the specific capacitance,and also on the square of the maximum capacitive cell voltage(UMcV).Thus,electrodes with high specific surface area(SSA)and electrolytes with excellent electrochemical stability are commonly reported in the *** electrolytes are safer and green devices compared to other organic-based *** the other hand,their UMcVis reduced compared to other electrolytes(e.g.,organic-based and ionic liquids).In this sense,spanning the UMcVfor aqueous-based electrolytes is a’hot topic’***,the lack of protocols to establish reliable UMcVvalues has culminated in the publishing of several conflicting ***,we confirm that multiwalled carbon nanotubes(MWcNTs)housed in cells degrade and produce cO_(2) under abusive polarisation *** is probed by employing electrochemical techniques,in-situ FTIR and in-situ Raman *** these considerations,the current study uses spectro-electrochemical techniques to support the correct determination of the electrode and electrolyte stability conditions as a function of the operating electrochemical parameters.

关键词： Electrode and electrolyte stabilities In-situ FTIR cO_(2)formation carbon degradation Supercapacitor Aqueous electrolytes carbon nanotubes

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空间定位的一般原理

系统工程与电子技术 1980年第3期 55-60页

作者： Kochi K.c. ,Dibble h.L. ,王永平

研究采用光学观测方法进行天文定位的理论是有指导意义的。这种理论由于它的几何特性可以使人们对一般的弹道参数估算问题认识得更深刻。

关键词：单位向量空间定位圆锥面夹角瞄准线天体视差六分仪导航设备恒星望远镜系统空间飞行器航天器距离向量方程组联立方程惯性系统光学定位

The Influence of high-energy Ball Milling and Sintering Process on the Microstructure and Mechanical Properties of Al-Ni-Y-co-La Alloy

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The Influence of High-energy Ball Milling and Sintering Proc...

同时采用放疗和替莫唑胺化疗治疗胶质母细胞瘤:利用定量动态对比增强MR成像区分假性进展与真性进展

中国材料大会2012

作者： Y. B. Yuan R. X. Zheng S. J. Ge h. Yang c. L. Ma Key Laboratory of Aerospace Advanced Materials and Performance of Ministry of Education School of Materials Science and EngineeringBeiHang University

ISBN: (纸本)9783037856079

Al86Ni7Y4.5co1La1.5 （at.%） alloy powder was produced by argon gas atomization process. After high-energy ball milling, the powder was consolidated and extruded by using vacuum hot press sintering under different process conditions, sintering temperature, extrusion pressure, sintering time, etc.. The microstructure and morphology of the powder and consolidated bulk alloy were examined by X-ray diffraction （XRD）, scanning electron microscopy （SEM） and transmission electron microscopy （TEM）. The phase transformation of the powder was investigated by differential scanning calorimetry （DSc）. Mechanical properties of the consolidated bulk alloy were examined. The results showed that as the milling time increase, the volume fraction of amorphous materials and the hardness and yield strength of the bulk alloy were obvious improved.

关键词： Al Alloy high Energy Ball Milling Multi-modal Nanocrystalline

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国际医学放射学杂志 2015年第3期 272-273页

作者： T.J.Yun c.K.park T.M.Kim S.h.Lee J.h.Kim c.h.Sohn 俞瀛一 Institute of Radiation Medicine Seoul National Univer sity Medical Research Center28 Yongon-dong Chongno-gu Seoul 110-744 Republic of Korea

目的本研究目的是基于胶质母细胞瘤病人在同时采用放疗和替莫唑胺化疗治疗后出现新发病灶或原病灶强化范围扩大,探讨动态对比增强MR成像在区分假性进展

关键词：动态对比增强假性进展胶质母细胞瘤 MR 替莫唑胺替莫唑铵化疗治疗

Non-Maxwellian electron distributions resulting from direct laser acceleration in near-critical plasmas

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Matter and Radiation at Extremes 2016年第1期1卷 82-87页

作者： T.Toncian c.Wang E.Mccary A.Meadows A.V.Arefiev J.Blakeney K.Serratto D.Kuk c.chester R.Roycroft L.Gao h.Fu X.Q.Yan J.Schreiber I.Pomerantz A.Bernstein h.Quevedo G.Dyer T.Ditmire B.M.hegelich Department of Physics University of TexasAustinTX78712USA State Key Laboratory of Nuclear Physics and Technology Peking UniversityBeijing100871China Fakultat fur Physik Ludwig-Maximilians-UniversityMunichGermany

The irradiation of few-nm-thick targets by a finite-contrast high-intensity short-pulse laser results in a strong pre-expansion of these targets at the arrival time of the main *** targets decompress to near and lower than critical densities with plasmas extending over few micrometers,*** *** interaction of the main pulse with such a highly localized but inhomogeneous target leads to the generation of a short channel and further self-focusing of the laser *** at the Glass hybrid OPcpa Scaled Test-bed(GhOST)laser system at University of Texas,Austin using such targets measured non-Maxwellian,peaked electron distribution with large bunch charge and high electron density in the laser propagation *** results are reproduced in 2D PIc simulations using the EPOch code,identifying direct laser acceleration(DLA)[1]as the responsible *** is the first time that DLA has been observed to produce peaked spectra as opposed to broad,Maxwellian spectra observed in earlier experiments[2].This high-density electrons have potential applications as injector beams for a further wakefield acceleration stage as well as for pump-probe applications.

关键词： Direct laser acceleration Electron acceleration Near critical plasmas PIc simulations

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Rheological Studies of Unpolymerized Light-cured composite Resin Rein forced with Retentive Filler ***,***,***

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Rheological Studies of Unpolymerized Light-cured Composite R...

Vitamin D deficiency: correlation to interleukin-17, interleukin-23 and PⅢNP in hepatitis c virus genotype 4

海南省口腔医学会第二次会员代表大会暨学术会议

作者： P.Xu,h.c.Xu,T.Wang Dental Materials Laboratory,Peking University School of Stomatology,Beijing 100081,P.R.china

The goal of this study was to investigate the rheological properties of unpolymerized light-cured composite resin reinforced with retentive filler (RF) and its rheological difference with that reinforced with normal filler (NF).The light-cured composite resins employed in this study were composite resin reinforced with RF (Experimental composite resin I,EcR-Ⅰ) and composite resin reinforced with NF (Experimental composite resin Ⅱ,EcR-Ⅱ).The rheological properties of EcR-Ⅰor EcR-Ⅱ,such as viscosity,shear rate,shear stress and shear strain,were measured with dynamic stress rheometer at 25 *** viscosity,shear rate,shear stress and shear strain of these composites were compared and *** results indicated EcR-Ⅰexhibits dilatant nature,and EcR-Ⅱnearly Newtonian;the viscosity o fEcR-Ⅰis larger than that of EcR-Ⅱ,and the shape of EcR-Ⅰis more stable than that of EcR-Ⅱin room ***,EcR-Ⅰand EcR-Ⅱneed different manipulation during clinical use.

关键词： Dental materials composite resin Viscosity Rheology Retentive filler

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World Journal of Gastroenterology 2012年第28期18卷 3738-3744页

作者： Mona F Schaalan Waleed A Mohamed hesham h Amin Department of Biochemistry Faculty of Pharmacy Misr International University Cairo 1 Egypt Department of chemistry Cairo University Cairo 11562 Egypt Department of clinical pathology Faculty of Medicine AL Azhar University Cairo 147 Egypt

AIM: To assess vitamin D (Vit D) abnormalities in hepatitis c infected patients and their relationship with interleukin (IL)-17, IL-23 and N-terminal propeptide of type Ⅲ pro-collagen (PⅢNP) as immune response mediators. METhODS: The study was conducted on 50 Egyptian patients (36 male, 14 female) with hepatitis c virus (hcV) infection, who visited the hepatology Outpatient clinic in the Endemic Disease hospital at cairo University. patients were compared with 25 ageand sexmatched healthy individuals. Inclusion criteria were based on a history of liver disease with hcV genotype 4 (hcV-4) infection (as new patients or under followup). Based on ultrasonography, patients were classified into four subgroups; 14 with bright hepatomegaly; 11 with perihepatic fibrosis; 11 with hepatic cirrhosis; and 14 with cirrhosis and hepatocellular carcinoma (hcc).Total Vit D (i.e., 25-Oh-Vit D) and active Vit D [i.e., 1,25-(Oh) 2 -Vit D] assays were carried out using commercial kits. IL-17, IL-23 and PⅢNP levels were assayed using enzyme linked immunosorbent assay kits, while hcV virus was measured by quantitative and qualitative polymerase chain reaction. RESULTS: Levels of Vit D and its active form were significantly lower in advanced liver disease (hepatic cirrhosis and/or carcinoma) patients, compared to those with bright hepatomegaly and perihepatic fibrosis. IL-17, IL-23 and PⅢNP levels were markedly increased in hcV patients and correlated with the progression of hepatic damage. The decrease in Vit D and active Vit D was concomitant with an increase in viral load, as well as levels of IL-17, IL-23 and PⅢNP among all subgroups of hcV-infected patients, compared to normal healthy controls. A significant negative correlation was evident between active Vit D and each of IL-17, IL-23 and PⅢNP (r = -0.679, -0.801 and -0.920 at P ctively). hcV-infected men and women showed no differences with respect to Vit D levels. The viral load was negatively correlated with Vit D an

关键词： Vitamin D Interleukin-17 Interleukin-23 N-terminal propeptide of type Ⅲ pro-collagen hepatitis genotype 4