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91.
本文报导了聚4-氨基联苯的电化学合成,测定了它的ESR、IR及紫外可见光谱。聚合物在THF、DMF和DMSO中能全部溶解。界面移动法测得聚4-氨基联苯的DMF饱和溶液中正离子的迁移率为1.48×10~(-8)m~2·S~(-1)·V~(-1)。  相似文献   
92.
The ability to quantitatively map the distribution of elements on the micrometer scale and smaller with high sensitivity and isotopic discrimination is unique to ion microscopy. The information contained in ion images can be crucial to the study of the solid state, where chemical heterogeneity is often directly related to observed behavior. The tools of digital image processing allow the extraction of quantitative information from the image data. These techniques coupled with improved instrumentation for the detection of ion images drastically increase the problem solving capabilities of the ion microscope. The use of such methods and instrumentation in the ion microscopic analyses of cell cultures and tissues of biological and biomedical relevance will be discussed.  相似文献   
93.
A molecular dynamics method has been used to simulate the argon ion-assisted deposition of Cu/Co/Cu multilayers and to explore ion beam assistance strategies that can be used during or after the growth of each layer to control interfacial structures. A low-argon ion energy of 5–10 eV was found to minimize a combination of interfacial roughness and interlayer mixing (alloying) during the ion-assisted deposition of multilayers. However, complete flattening with simultaneous ion assistance could not be achieved without some mixing between the layers when a constant ion energy approach was used. It was found that multilayers with lower interfacial roughness and intermixing could be grown either by modulating the ion energy during the growth of each metal layer or by utilizing ion assistance only after the completion of each layers deposition. In these latter approaches, relatively high-energy ions could be used since the interface is buried and less susceptible to intermixing. The interlayer mixing dependence upon the thickness of the over layer has been determined as a function of ion energy.  相似文献   
94.
The reaction of bis(hydroxymethyl)phenylphosphine with isobutyl diphenylborate in the presence of triethylamine leads to the formation of triethylammonium 2,2,5-triphenyl-1,3,2,5-dioxaborataphosphorinane (1). The reaction of compound 1 with electrophilic reagents (O, S, Se, CH2O, RHal) leads to quaternization of the phosphorus atom, giving the corresponding phosphine oxides, sulfides, and selenides and P,B-containing betaines. In the reactions of compound 1 with amines aminomethylphosphines of the diazaphosphorinane and diazadiphosphacyclooctane series are formed. Ammonium 1,3,2,5-dioxaborataphosphorinanes dissociate in solutions and enter into ion exchange with phosphonium iodides, leading to phosphonium 1,3,2,5-dioxaborataphosphorinanes. The latter, in the case of the aminomethylphosphonium cation, undergo intramolecular rearrangement with the formation of P,B-containing betaines and aminomethylphosphines.Deceased.A. E. Arbuzov Institute of Organic and Physical Chemistry, Kazan' Scientific Center, Russian Academy of Sciences, 420083 Kazan'. Translated fromIzvestiya Akademii Nauk, Seriya Khimicheskaya, No. 6, pp. 1398–1405, June, 1992.  相似文献   
95.
彭德全  白新德  潘峰  孙辉 《物理学报》2005,54(12):5914-5919
用金属蒸汽真空弧源,以40kV加速电压对纯锆样品分别进行了1016—1017/cm2的钇、镧离子注入,注入温度约为130℃.然后对注入样品进行表面分析.x射线光电子能谱分析表明,注入的钇以Y2O3形式存在,镧以La2O3形式存在.俄歇电子能谱表明,纯锆基体表面的氧化膜厚度随着离子注入剂量的增加而增加,当离子注入剂量达到1017/cm2时,氧化膜的厚度达到了最大值.卢瑟福背散射显示镧层的厚度约为30nm,同时直接观察到当离子注入剂量为(La+Y)1017/cm2时,纯锆样品表面发生了严重的溅射. 关键词: 纯锆 钇和镧离子共注入 卢瑟福背散射 x射线光电子能谱  相似文献   
96.
The rate of anodic oxidation of the hypophosphite ion on alloys Ni-P, Ni-B, and Ni-Mo-P is studied as a function of their composition and structure. The organic compounds that are customarily used to stabilize electrolytes of electroless nickel plating are shown to come useful when controlling composition of the Ni-P coatings at the expense of their different influence on the rates of partial processes of deposition of the alloy components. The formation of catalytic activity of such coatings is affected mostly by a structural factor. With alloys Ni-P, Ni-B, and Ni-Mo-P, whose composition was varied by altering the concentration of the source of the alloying component, dependence of catalytic activity of the surface on the composition is defined mainly by an electronic factor.__________Translated from Elektrokhimiya, Vol. 41, No. 8, 2005, pp. 972–980.Original Russian Text Copyright © 2005 by Sotskaya, Dolgikh, Ryabinina.  相似文献   
97.
l.IntroductionowingtotheirpromisingproPertiesandPOtentialapplications,transitionmetalni-trideshavedrawngreatattentionandthepreparationandinvestigationofthesecom-poundshavebeenasubjectbothofscientificandoftechnologicalinterest.Transitionmetalnitridescombineadvantagesofexce1lenthardness,highmeltingPOint,goodchemi-calstabilityandhigheIectricalconductivity[11,henceoverlaySofthesecompoundshavefoundwideappIicationsinvariousfie1ds.Molybdenumnitrides,inparticular,havealsoemergedasverypromisingcandi…  相似文献   
98.
对Ce3+ ∶Eu3+ ∶Cr3+ ∶Sm3+ ∶YAG处延层中的荧光敏化现象进行了报道和分析 ,在较高浓度的Ce3+ 离子掺杂时 ,外延层在蓝色、绿色波段出现了新的荧光谱线 ,可解释为在Ce3+ 离子敏化作用下 ,Eu3+ 离子产生了由高位激发态能级5Di(i=1,2 ,3)直接到基态能级7Fj(j =0 ,1,2 ,3)的辐射跃迁过程 ,并且这种Ce3+ ∶Eu3+ ∶Cr3+ ∶Sm3+ ∶YAG外延层还是一种新颖的白色单晶荧光材料。  相似文献   
99.
《Pramana》2003,61(5):865-876
Particle production in Au+Au collisions has been measured in the PHOBOS experiment at RHIC for a range of collision energies for a large span of pseudorapidities, |η| < 5.4. Three empirical observations have emerged from this data set which require theoretical examination. First, there is clear evidence of limiting fragmentation. Namely, particle production in central Au + Au collisions, when expressed as dN/dη′ ( η′ ≡ – ybeam), becomes energy independent at high energy for a broad region of η′ around η′ = 0. This energy-independent region grows with energy, allowing only a limited region (if any) of longitudinal boost-invariance. Second, there is a striking similarity between particle production in e+eand Au + Au collisions (scaled by the number of participating nucleon pairs). Both the total number of produced particles and the longitudinal distribution of produced particles are approximately the same in e+eand in scaled Au + Au. This observation This presentation is based in large part on the PHOBOS summary talk by M Baker at the16th Int. Conf. on Ultrarelativistic Nucleus- Nucleus Collisions, Quark Matter 2002, Nantes, France was not predicted and has not been explained. Finally, particle production has been found to scale approximately with the number of participating nucleon pairs for (N part ) > 65. This scaling occurs both for the total multiplicity and for highp T particles (3 <p T < 4.5 GeV/c). This presentation is based in large part on the PHOBOS summary talk by M Baker at the16th Int. Conf. on Ultrarelativistic Nucleus-Nucleus Collisions, Quark Matter 2002, Nantes, France  相似文献   
100.
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