Refractory compounds of basic composition for the monolithin lining of steel-teeming ladles

Conclusions Questions of the method of production of basic ramming compounds at Panteleimonovka Refractory Plant and their use in the monolithic lining of the walls of 160-ton steel-teeming ladles of the No. 2 Converter Shop of Kirvoi Rog Steel Combine are considered.An analysis of the wear of the lining during service showed that it occurs as the result of spalling of the sintered zone and salamandering of the lining. The use of a movable thermally insulated lid made it possible to hold the temperature of the ladle lining within limits of 730–1120°C between heats and to obtain a basic rammed lining life of 21–39 heats as opposed to an average life for the shop of 14.8 heats.A reserve for increasing the ladle basic lining life is optimization of the thermal conditions of its service, including high-temperature heating of the lining before pouring of the metal, the use of thermally insulated lids with the minimum consumption of time for placing of them, an increase in the life of the well refractory to the life of the walls and bottom, and elimination of cooling of the lining between heats.A Discussion: Problems of the Production and Use of Refractories for the Lining of Steel-Teeming Ladles. [For the start of the discussion see No. 8 (1988) and for the continuation Nos. 9–12 (1988) and Nos. 1–3, 5, and 7 (1989).]Deceased.I. I. Glaka, N. F. Drobot, N. V. Kurmaz, B. P. Zinchenko, S. A. Poznyak, I. M. Ryaboshapkin, V. V. Slushko, A. A. Chulkov, Yu. Bormatov, S. I. Vanchyuk, V. I. Dobrovol'skii, B. G. Zhuravel', N. I. Kiyan, L. I. Nekrasov, N. M. Sokolov, P. V. Khomenko, G. A. Nikitenko, S. Dorgobuzov, P. I. Valiev, N. N. Gorbatko, V. I. Kovalenko, and M. I. Lyakhov of Krivoi Rog Steel participated in the preparation and tests of the basic monolithic linings.Translated from Ogneupory, No. 8, pp. 1–4, August, 1989.     

Gel permeation chromatography measurements on PVC resins and plasticisers

The value of gel permeation chromatography (g.p.c.) measurements of PVC resins is discussed in relation to quality control of commercial suspension types. Some examples of simple solvent fractionation and precipitation with methanol are given. In addition, chromatograms of selected plasticisers are shown for analytical identification together with an indication of an approximate determination of the mol. wt. of plasticisers ranging from 400–10,000. Finally a short discussion of the influence of the parameters of operation, i.e. flow rate, volume of injection and concentration of the solution in tetrahydrofuran, is given. It is concluded that g.p.c. determinations of weight-average mol. wt. are in fair agreement with light-scattering measurements.     

Effect of the density of the electronic states at the valence orbital of the bridge redox molecule on the dependence of the tunnel current on the overvoltage in the case of fully adiabatic electron transition

Effect of the density of the electronic states at the valence orbital of the bridge redox molecule on the dependence of the tunnel current on the overvoltage and on the width at half maximum of the current-overvoltage curve is studied. A number of the approximate expressions for the density of states, the tunnel current and the width are obtained in the fully adiabatic limit for different particular cases. It is shown that at small values of the coupling of the electronic levels of the electrodes with the valence orbital of the redox molecule and the small values of the bias voltage two regions of the reorganization Gibbs energy exist with different dependence of the width on the reorganization Gibbs energy. The results of calculations of the density of states, the tunnel current and the width are presented and used for the interpretation of the experimental data [N.G. Tao, Phys. Rev. Lett. 76 (1996) 4066, I. Visoly-Fisher, K. Daie, Y. Terazono, C. Herrero, F. Fungo, L. Otero, E. Durantini, J.J. Silber, L. Sereno, D. Gust, T.A. Moore, A.L. Moore, S.M. Lindsay, PNAS 103 (2006) 8686].     

The compositions of some unhydrolyzed naturally occurring waxes,calculated using functional group analysis and fractionation by molecular distillation,with a note on the saponification of carnauba wax and the composition of the resulting fractions

Summary Methods for the determination of acid, ester, hydroxyl, and ketone (or aldehyde) groups and of mean molecular weights of small samples of natural waxes are reported. Complete analyses can be made on 0.5 g. of sample. A simplified procedure for quantitative separation of acid and unsaponifiable fractions of a wax is also reported. Molecular distillations of beeswax, caranda wax, crude and refined candelilla wax, and ouricury wax, have fractionated these complex mixtures into simpler ones. Hydrocarbons and free unsubstituted alcohols and acids, if present, distil readily at 150°C. A pot still suitable for convenient molecular distillation of up to 100-g. charges of waxes or other high melting materials is described. A method for the calculation of composition of unhydrolyzed waxes based upon function group analysis of molecular distillation fractions is described. Results of application of this method to the waxes distilled are reported and show the ubiquitousness of hydroxy acids. All of the above waxes and carnauba wax contain major proportions of esters of the hydroxy acids, and none contains as much as one-half simple esters of unsubstituted acids and alcohols. A portion of a dissertation submitted by Thomas Wagner Findley to the Graduate School of the Ohio State University in partial fulfilment of the requirements for the Ph.D. degree. S. C. Johnson and Son Inc. Fellow in Physiological Chemistry, 1946-50.     

Reflection of a shock wave from a rigid wall in a mixture of a liquid metal and solid particles

The problem of reflection of shock waves and expansion waves from a rigid wall in a mixture of liquid iron and small molybdenum crystals is considered. The study is performed within the framework of equilibrium and nonequilibrium approximations of mechanics of heterogeneous media with different pressures of the components. The mathematical model is verified by fitting the dependence of the equilibrium-frozen velocity of sound on the initial pressure in the mixture with available experimental data. In the equilibrium approach, the dependence of the type of the reflected wave on the type of the incident wave is determined. Direct numerical calculations within the framework of the nonequilibrium model of mechanics of heterogeneous media confirmed the validity of the reflection chart obtained. The possibility of significant compacting of molybdenum particles in reflected waves is revealed. Translated fromFizika Goreniya i Vzryva, Vol. 36, No. 4, pp. 97–107, July–August, 2000. This work was performed within the framework of the Integration Project No. 97-24 of the Siberian Division of the Russian Academy of Sciences.     

Chemical nature of pre-asphaltenes from flash pyrolysis tars and supercritical gas extracts

Pre-asphaltenes from flash pyrolysis tars of three Australian coals and a supercritical gas extract of one of these coals were studied by ¹³C and ¹H n.m.r. of the silylated pre-asphaltenes. Further information was obtained by hydrogenolysis of one of the pre-asphaltenes followed by g.c. analysis. ¹³C n.m.r. studies of the silylated derivatives and g.c. analysis of the hydrogenated pre-asphaltene showed the presence of long alkyl chains. The aromaticity of the pre-asphaltenes from the flash pyrolysis tars increased as the rank of the coal increased. The pre-asphaltene from the supercritical gas extract was less aromatic than that from the flash pyrolysis tar of the same coal. Average structural data for each of the pre-asphaltenes are reported.     

恒pH滴定法测定二苯胺中苯胺的含量

在质量浓度为95％的乙醇溶液中。以适当浓度的HCI溶液为滴定剂,分别对系列苯胺标准溶液滴定至选定的pH值,绘制HCI溶液消耗体积与苯胺含量的标准曲线,由该曲线求出未知样中苯胺的含量。结果表明,该方法测量的准确性高,相对误差≤1．2％,相对平均偏差为0.2％,二苯胺的存在对苯胺的测定不产生影响。与现用方法相比,该法不需要进行苯胺与二苯胺的分离,也无需对滴定剂进行标定;该法可用于工业上二苯胺中苯胺含量的测定。     

在Mo-Bi-Ce/SiO_2催化剂上丁烯-2氧化脱氢的内扩散影响

用玻璃流动外循环无梯度反应器研究了Mo—Bi—Ce/SiO_2催化剂上丁烯-2氧化脱氢的内扩散影响.确定了催化剂的有效因子,多孔催化剂的有效因子随反应温度的升高而减小.在内扩散区域的反应活化能为丁烯-2扩散活化能、动力学区域反应活化能的算术平均值.在内扩散区域的丁烯氧化脱氢生成丁二烯的选择性用经验式描述.     

Fractal structure and features of energy-release (combustion) processes in heterogeneous condensed systems

In this work, the theory of fractals has been used to describe the structure of heterogeneous condensed systems (HCS). Features of energy-release processes with variation of the initial structure parameters have been investigated. The microstructure of HCS and the dynamics of its change have been studied as functions of the proportion and properties of their components. It is shown that particles of the components form fractal structures, which are characterized by fractional dimensions. The obtained images of the microstructure reflect the presence of the geometric phase transition “fractal cluster-percolation cluster.” Regularities of reaction-front propagation are determined. It is found that the concentration limits of energy release and combustion are associated with the evolution of fractal structures and the formation (disruption) of a continuous reaction surface. The electrical conductivity of the starting compositions is measured as an indicator of the formation of fractal structures of one or another configuration. Electrical and thermal-physics properties of the samples and energy-release (combustion) parameters are analyzed. The systems exhibit similar behavior in different processes. Near the critical point, the dependence of the parameters studied on concentration has an exponential character. The exponent is close to that determined in percolation theory. A computational algorithm for the contact surface of the components is developed and implemented. The computation results allow one to distinguish the “base block” that influences the combustion rate and to determine the critical concentrations of the components. The study of HCS in the context of the new direction in the geometry of disordered systems—the theory of fractals—is promising for generalization of available experimental data and for predicting the parameters of energy release in HCS with variation in the structural parameters. Institute of Chemical Physics, Russian Academy of Sciences, Moscow 117977. Translated from Fizika Goreniya i Vzryva, Vol. 33, No. 5, pp. 3–19, September–October, 1997.     

13C n.m.r. study of the structure of poly(aspartic acid)

From hydrolysis of the product of thermal polycondensation of aspartic acid, poly(succinimide), under various conditions, a series of samples of thermal poly(aspartic acid) was obtained. These polymers differed by molecular mass and, from n.m.r. spectral evidence, by the contents of α and β peptide bonds, depending mostly on the pH of hydrolsysis. The contents of α and β bonds found were further confirmed by analysis of the n.m.r. spectra of the complex of poly(aspartic acid) with Co(II). Also, spectra of poly(aspartic acid) obtained by debenzylation of poly(β-benzyl-l-aspartate) described in our previous work were analyzed in greater detail. A comparison of racemic and optically pure polymers has shown that the n.m.r. spectra are only slightly affected by stereoregularity, and that stereoregularity is not the cause of the splitting of the various carbon bonds. Analysis of the complicated structure of the spectra, mainly of the carbonyl group, leads us to the conclusion that the distribution of the α and β bonds is random in all the polymers studied.     

Etude de l'oxydation des carbones en oxyde graphitique

The oxidation of several types of carbons leading to the formation of lamellar oxides was studied. The progression of formation of graphitic oxides was followed by use of X-ray diffraction, i.r. spectroscopy, electron microscopy and by a study of carbon dioxide evolution. Kinetic studies of the formation of carbon dioxide indicate the existence of two reaction stages during the oxidation. The fraction of carbon transformable into graphitic oxides is independent of the reaction temperature and carbon characteristic. The oxidation rate of graphitic oxide into carbon dioxide depends on the structural organization of the initial carbon.     

The study of aluminum soap-hydrocarbon systems: Effect of additives and metathesis

Summary Many additives have pronounced and manifold effects on the behavior of aluminum soaps-hydrocarbon systems. Some additives accelerate the formation of jellies, other retard it. Some thicken the jellies, others liquefy them. The mechanism of the action of additives is probably manifold, too. One of the many possible mechanisms is that of metathesis between the fatty acid radical of the soap and acidic additives. The actual occurrence of such metathesis is demonstrated by both qualitative observations of a variety of systems and by the preparation in benzene of aluminum dibenzoate from the dilaurate. Presented before the Division of Colloid Chemistry at the 113th meeting of the American Chemical Society, April 19, 1948, in Chicago, Illinois. Study conducted under Contract OEM-1057 between Stanford University and the Office of Emergency Management, recommended by Division 11.3 of the National Research Council, and supervised by Prof. J. W. McBain.     

Homogenizing role of hydrogen in the synthesis of multicomponent Carbohydrides and Nitridohydrides of transition metals in the combustion mode

This work presents the results of study of combustion with carbon of transition metals of IV, V and VI groups of the periodic system in atmospheres of argon, hydrogen, nitrogen and nitrogen-hydrogen mixture. The significance of hydrogen in the formation of single-phase products in the self-propagating high-temperature synthesis (SHS) mode was underlined. The combustion of carbon containing systems in argon resulted in the synthesis of two-phase carbides with FCC lattice. In contrary, the combustion of the same systems in hydrogen atmosphere leaded to the synthesis of single-phase carbo-hydrides. The products of combustion of transition metals in nitrogen atmosphere were the multiphase nitrogen-containing compounds. Their following re-ignition in hydrogen leaded to the synthesis of single-phase nitrido-hydrides. It was demonstrated that in all the studied systems, the combustion in hydrogen atmosphere leaded to the homogenized final synthesis products. The results of these processes were the formation of single-phase carbo- and nitrido-hydrides based on the metals of IV, V and VI groups. The presence of hydrogen in the crystal lattice of synthesized refractory carbides and nitrides facilitated easy dispersion of the compound to submicron sizes. After removal of hydrogen, the single phase structure was not violated. The described results may be of commercial value in the industry of refractory materials.     

HpaA蛋白在幽门螺杆菌感染诊断中的应用

目的建立检测血清HpaA抗体的ELISA间接法,探讨以重组蛋白作为抗原在诊断H.pylori感染中的价值。方法将从临床分离菌株中获得的HpaA基因在大肠杆菌中表达,用Ni2+-NTA柱纯化表达的HpaA作为抗原,建立检测血清HpaA抗体的ELISA间接法,与诊断标准比较评价其应用的可行性。结果经超声破碎后,用SDS-PAGE分析显示,HpaA蛋白主要存在于上清中,纯化抗原检测临床标本中HpaA抗体的敏感性和特异性分别为100.0%和90.1%。结论以重组蛋白为抗原初步建立检测血清HpaA抗体的ELISA间接法敏感性、特异性高,为制备商品化的试剂盒奠定了基础。     

串联攻坚战斗部前级爆轰场对后级影响分析

为了研究串联战斗部前级爆轰场作用下,后级随进子弹炸药安全性及其速度降的大小,建立了一维冲击波传播理论分析模型,由图解法得到了后级装药的初始压力。通过与炸药引爆阈值压力比较,判断了后级装药的安全性。根据动量守恒,得到了后级子弹的速度降表达式。进行了串联装药的数值计算,得到一定隔板厚度情况下后级装药受到的冲击压力和后级子弹速度降,计算得到的后级子弹变形情况与试验结果相吻合。     

The bulk-dyeing of cellulose acetate with disperse aldehyde dyes

Conclusions 1. The possibility of obtaining dyed cellulose acetate by the addition to an acetonic solution of cellulose acetate of acetone-soluble aldehyde dyes which form strong chemical bonds with it has been studied.2. The optimum conditions for bulk-dyeing with aldehyde dyes have been worked out.3. It has been shown that the reaction of an aldehyde dye with cellulose diacetate leads to partial saponification of the acetyl groups. The hypothesis has been put forward of the subsequent acetylation of the hydroxy groups liberated by the aldehyde dyes.Institute of Chemistry, Academy of Sciences of the Tadzhik SSR. Novosibirsk Institute of Organic Chemistry, Siberian Division of the Academy of Sciences of the USSR. Translated from Khimicheskie Volokna, No. 3, pp. 39–41, May–June, 1969.     

DSMC prediction of granular temperatures of clusters and dispersed particles in a riser

Flow behavior of gas and particles in a CFB riser is simulated by a Euler-Lagrangian approach. Collisional interaction of particles is modeled by a direct simulation Monte Carlo (DSMC) method. The coefficient of restitution depends on the relative velocity between two particles by taking into account both the viscoelastic and plastic deformations of particles. The Newtonian equations of motion are solved for each simulated particle in the system. The interaction between gas phase and simulated particles is determined by means of Newtonian third law. A criterion proposed by Soong et al. [C.H. Soong, K. Tuzla, J.C. Chen, Experimental determination of clusters size and velocity in circulating fluidized beds, in: J.F. Large, C. Laguerie Eds., Fluidization VIII Engineering Foundation, New York, 1995, pp. 219-227.] is used to obtain information of clusters. A model for the determination of the number of particles inside a cluster is proposed from kinetic theory of granular flow. The flow behavior of clusters and dispersed particles in the riser is numerically predicted. Distributions of granular temperature of clusters and dispersed particles are computed from velocity distributions. The upward moving clusters give a high granular temperature in comparison to the downward moving clusters. The granular temperature of the dispersed particles is an order of magnitude larger than that of the clusters. The computed collision frequencies of dispersed particles and clusters from DSMC are lower than those from kinetic theory of granular flow.     

流行性腮腺炎病毒疫苗株WM84六代次基因序列分析

目的分析6个代次流行性腮腺炎病毒疫苗株WM84融合蛋白(F)、血凝素神经氨酸酶蛋白(HN)和疏水蛋白(SH)的基因序列,并与Jery-Lynn(JL)株和ME株进行比较。方法WM84株病毒在原代鸡胚成纤维细胞(CEF)上连续传代至12代,观察各代病毒的培养特性,测定2、7、9、10、11、12代主要结构蛋白基因及高变区SH基因序列,与GenBank中参考毒株JL2、JL5和ME株进行比对,分析其核苷酸序列及相应氨基酸序列的差异,并构建系统进化树。结果WM84株病毒在CEF上连续传代至12代,其培养特性及病毒滴度基本稳定。与WM84株2代相比,其各代在主要蛋白基因区域有散在的核苷酸变化。7～12代病毒HN、F和SH基因与2代相比,核苷酸同源性分别为97.0%～100%、97.0%～100%及94.0%～100%;氨基酸同源性分别为98.3%～100%、97.2%～100%及94.1%～100%。2～7代病毒,HN、F和SH基因氨基酸与JL2株同源性为98.8%～99.5%,与JL5株同源性为94.1%～98.3%,传至11、12代,与JL5株同源性达99.8%～100%。结论WM84株2～7代病毒蛋白基因与JL2株十分相似,但在后续传代过程中出现了JL2株向JL5株转化的倾向。WM84株病毒在传代过程中HN及F基因结构基本稳定。     

Stabilisierung von Polypropylen durch Mischungen substituierter Phenole und Di-n-alkylsulfide

This paper is dealing with the synergistic effect of some phenolic antioxidants, e.g. 4,4′-butylidene-bis(3-methyl-6-tert.-butylphenol), 2,2′methylidene-bis(4-methyl-6-tert.-butylphenol) and 4,4′-thio-bis(3-methyl-6-tert.-butylphenol) with di-n-alkylsulfides of various chain lengths and of sulphoxides and sulphones of the latter on the induction period of oxidation of polypropylene. The influence of the type of the phenolic antioxidants in the mixtures of stabilizers, the influence of the length of the alkyl chain of the sulphide component and the influence of the temperature was studied. Because an interaction between the mentioned substances and the formed peroxides during the inhibition of polypropylene in the presence of sulphides and their derivates was considered, the effect of sulphides, sulphoxides and sulphones on the decomposition of tert.-butyl hydroperoxides was studied.     

Realization of the properties of carbon fibres in composite materials. Part 2. Carbon fibre composites with a metal matrix (review)

The features of fabrication of metal composites complicates realization of the strength of CF in comparison to carbon-filled plastics. Disordering of the fibres and matrix is possible due to excessive interaction of the components. Three types of structure of metallic carbon materials (MCM) corresponding to insufficient, optimum, and excessive interaction of the components of CM are described. The principles of a quantitative theory of interaction of components in fabrication of MCM are examined and can be used to estimate the optimum parameters of this process.Avtor Scientific and Industrial Co., Mytishchi. Translated from Khimicheskie Volokna, No. 3, pp. 37–42, May–June, 1995.