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1.
《广州化学》2011,36(3):76-76
[1]稿件内容须符合本刊的报道宗旨,论点鲜明,数据可靠,文字简练。[2]题目论文题目应准确、简明地表达文章的主题内容,字数不超过20字。不应有非规范的缩略词、符号、代号。文内标题序号用阿拉伯数字,以"1、1.1、1.1.1"三级标题表示。标题一般不超过15个字,不加标点符号。[3]署名作者署名一般不超过5人。首页脚注第...  相似文献   

2.
氧化还原反应在生活中应用的趣味性探究课。再现亚硝酸盐对机体的毒害,探讨其解毒原理,用厨房中的常见物质有效快速鉴别亚硝酸钠与氯化钠。贴近生活,材料易得,现象明显,操作简便。适于课堂探究与激趣。  相似文献   

3.
《应用化学》创刊于1983年,是经国家科委批准向国内、国外公开发行的学术性期刊。由中国科学院主管,中国化学会和中国科学院长春应用化学研究所主办,科学出版社出版。为中国科技核心期刊。《应用化学》设有综合评述、研究论文、研究简报、研究快报栏目。出版周期短,报道新成果快。  相似文献   

4.
2012年将迎来中国化学会80华诞。1932年,化学界的前辈们怀着拳拳爱国之心,抱着科学救国之志,自愿组成了这个学术团体。他们以民族大业为己任,对发展我国的化学化工和化学教育,做出了卓绝的贡献。在其后不到两年,本刊就作为中国化学会主办的学术刊物正式问世。忆往昔,岁月峥嵘,看今朝,前景辉煌。  相似文献   

5.
考察了焦煤中少量氧化铅添加剂对炼焦过程高温焦炉煤气硫化氢浓度以及对焦炭质量的影响。实验表明,煤中添加少量的氧化铅,可以达到焦炉粗煤气脱硫的目的,并且对焦炭的质量影响很小。针对实验所用的煤种,相当于焦煤质量的0.6%的氧化铅添加量在炼焦前期具有最佳的抑制硫释放的效果。炼焦后期,半焦中的硫化铅分解或铅转变为气态铅。气态铅和硫化氢在离开炼焦室时,由于煤气降低温度,又生成硫化铅。从而实现均相脱硫。焦炭中超过一半的铅可以挥发出去。在炼焦收缩阶段,半焦中过多的铅的存在不利于硫化铅的分解。  相似文献   

6.
补钙食物:畜类、虾类、谷类、黑色食品。补镁食物:蜂产品、昆虫类、叶菜类、水果类、鱼类。补锌食物:鱼类、贝类、豆类、蜂产品、昆虫类、禽类。补铁食物:禽类、黑色食品、叶菜类、菌类、昆虫类、动物血。补铜食物:虾类、贝类、瓜茄类、坚果类。  相似文献   

7.
L-核糖的合成研究进展   总被引:12,自引:1,他引:12  
L-核糖是合成L-核糖核苷抗病毒剂的重要中间体。综述了L-核糖的合成方法及 最新进展。重点讨论了L-核糖的化学合成方法,也介绍了L-核糖的微生物合成法。  相似文献   

8.
1.文摘应包含正文的要点。一般来说,文摘应包含研究对象(目的),研究方法(所用的设备、材料),结果与结论。2.文摘要尽量简短,尽可能删掉课题研究的背景信息。3.文摘中出现的数据应该是最重要、最关键的数据。4.不需要自己标榜自己的研究成果。  相似文献   

9.
1.文摘应包含正文的要点。一般来说,文摘应包含研究对象(目的),研究方法(所用的设备、材料),结果与结论。2.文摘要尽量简短,尽可能删掉课题研究的背景信息。3.文摘中出现的数据应该是最重要、最关键的数据。4.不需要自己标榜自己的研究成果。  相似文献   

10.
《化学进展》2012,(1):5-7
田禾精细化工专家。华东理工大学教授。1962年7月出生于新疆乌鲁木齐,籍贯江苏常熟。1982年7月毕业于南京理工大学化学化工学院,1986年7月和1989年1月在华东理工大学先后获硕士学位和工学博士学位。现任国际学术刊物Dyes and Pigments主编。  相似文献   

11.
The Langevin paramagnetic theory can’t describe the relation between magnetization of ferrofluids and applied magnetic field. The structuralization of ferrofluids, which is considered the main influence factor of the magnetization, is regarded. The part of magnetization works is deposited when the structure is forming. This action influences the magnetization of ferrofluids directly or indirectly. On the base of the “compressing” model, the Langevin function that usually describes the magnetization of ferrofluid is modified, and a well-fitted curve is obtained. An equation of the relation between the equivalent volume fraction after being “compressed” and the intensity of magnetic field is discovered, which approximately describes the process of magnetization. The relation between the approximate initial susceptibility and the volume fraction can be obtained from modified formula.  相似文献   

12.
We have theoretically resolved phonon excitations in quasi-two-dimensional organic crystals of polyacenic semiconductor material which may be obtained by the pyrolytic treatment of phenol-formaldehyde resin. A model for studying the dynamical properties using three polyacene chains is proposed with the aim to present the vibrational properties of this structure. It employs the formalism of solid states in two dimensions which admit phonons. A simulation process of the two-dimensional lattice structure shows that elastic waves may explain the existence of vibrational modes in the frequency range 100-400 cm-1. The presence of acoustic and optical like phonons is discussed in terms of the elastic force constants. A hyperfine resonance structure is obtained. It allows the analysis of the dynamical evolution in thin films of polyacene. It is found that the behavior of the phonon density of states exhibits resonance between modes in the structure.  相似文献   

13.
利用元胞动力学方法在二维情况下对浓度、取向序参量的含时Ginzberg-Landau方程进行数值求解,研究了液晶聚合物/柔性链聚合物共混体系的相分离动力学,考察了浓度、取向有序过程的耦合对相分离形态的影响.结果表明,此耦合作用对相分离的时间进程以及相分离图样的空间排布都有影响.液晶聚合物的取向有序相当于增加了两组分间的不相容性而促进两相分离;两个序参量在热力学方面的耦合使液晶聚合物趋向于沿着界面方向取向,而动力学方面的耦合使液晶聚合物分子沿着其取向方向扩散,相分离图样的空间排布由这两种效应共同决定通过极化率张量的定义用数值方法模拟得到了相分离体系的小角光散射图样,结果表明,散射强度分布具有方位角依赖性,它是由浓度、取向序参量的空间变化共同决定的.  相似文献   

14.
The applicability of the method of Giese to the measurement of the influence of monomer reactivity is examined. The reaction of alkyl mercuric salts with sodium borohydride permits the production of alkyl (cyclohexyl and butyl) radicals. Since hydrogen radicals are present in high concentration, the addition of alkenes to the reaction mixture leads to radicals from the alkenes. Further addition of alkene (polymerization) can be nearly completely excluded in this way. The composition of the reaction products is determined by gas chromatography. The addition rate of the alkenes relative to styrene allows correlation with the e value of the Q-e scheme of Alfrey and Price. The method answers the question of how far addition of the monomer complex occurs in one step or as separate addition of both monomers during copolymerization in the presence of charge-transfer (CT) complexes of the monomers. The investigations are performed by using the styrene/acrylonitrile/ZnCl2system, and it is demonstrated that the reactivity of the complexed  相似文献   

15.
Release of KCl from a batch of PMMA microcapsules containing an aqueous 3 mM KCl solution was studied with the following two methods: 1) dielectric measurements of suspensions of the microcapsules in distilled water. The electrical conductivity of capsule interior was estimated with this method. 2) Measurements of the conductivity of suspending medium of the microcapsule suspensions. These two kinds of experiments provided us with information about the amount of KCl remaining in the capsules and that diffused outside. Results of these experiments showed that the microcapsules varied in their release rate of KCl. A distribution function of the release rates was derived from the results of the dielectric measurements. That distribution function was successful in explaining the results of the measurements of the conductivity of suspending medium. Furrther examination revealed that the release rate increased with the increase in the thickness of capsule wall.  相似文献   

16.
Phase and structural relationships of the sulfur, selenium, and tellurium compounds of the 4d and 5d transition elements of groups IV to VII of the periodic system are discussed. Homologous elements behave very similarly with respect to the chalcogens, and this is particularly the case for niobium and tantalum, and for molybdenum and tungsten. However, zirconium, niobium, and molybdenum have a greater tendency towards formation of chalcogen-poor phases than their homologues hafnium, tantalum, and tungsten. Subchalcogenides are known only for zirconium and niobium. The number of phases and the tendency towards formation of solid solutions are considerably smaller among the tellurides than among the sulfides and selenides. The crystal structures of the telluride phases also differ from those of the sulfide and selenide phases of analogous composition. In addition, a review of the phase and structural relationships of the arsenic and antimony compounds of the 4d and 5d transition elements of groups V to VII is given.  相似文献   

17.
The equilibrium distribution of a trace impurity and the self-diffusion coefficients of molecules of the base component and the trace impurity in narrow cylindrical pores were calculated using the lattice-gas model. Two types of lattice structures with six and eight closest neighbors were considered. The sizes of the base component and impurity molecules were taken to be identical. Lateral interactions were taken into account in the quasi-chemical approximation. The equilibrium distributions of the trace impurity across a pore section in the gas and liquid phases of the base component and at the interface for the case of capillary condensation were considered. The probability of existence of isolated dimeric clusters was estimated and the self-diffusion coefficients of the base component and trace impurity for a single-phase distribution of the base component were calculated. The effects of the energy of interaction of impurities with the pore walls and the concentration of the base component on the diffusion mobility of the impurities were analyzed. The concentration dependences of the partition coefficient for the trace impurity between the pore center and the pore wall and the concentration dependences of the self-diffusion coefficients for the trace impurity molecules become nonmonotonic with an increase in the base component concentration. These effects are due to the displacement of the impurity from the near-surface area to the bulk of a pore following an increase in the pore coverage by the base component and to higher mobility of the impurity in the free bulk of the pore. Further filling of the pore bulk reduces the mobility of all molecules. The energetics of intermolecular interactions also plays a certain role. Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 4, pp. 605–615, April, 2000.  相似文献   

18.
基于偶极近似,运用电极化方法,定量研究了电流变液中悬浮颗粒在外电场作用下其体积和形状的变化,并计算了其体积和形状的相对变化率.研究结果表明:悬浮颗粒的体积和形状的相对变化率均与电场强度的平方成正比,并与ER本身的性质有关.一般情况下,颗粒的体积和形状的相对变化率分别为8.4%和12.5%,对总体积变化率的贡献为1.68%.这种变化对于ER系统的电涨和电热都作出了贡献,仅当将颗粒当作刚性球时,其自由能才与电场强度的平方成正比.  相似文献   

19.
The isothermal crystallizations of three kinds of commercial isotactic polypropylene have been studied by DSC and rheometric experiments, in a range of temperatures where the rate of crystallization is moderate. As the crystallization proceeds, volume contraction induces tensile force upon the parallel plates. The tensile force relaxed quickly in liquid states,but after a critical amount of the relative crystallinity, it starts to accumulate in the static test, that is, with the motionless parallel plates. A new method to determine the liquid-solid transition by the static tensile force is proposed and compared with two dynamic methods of detecting liquid-solid transition, that is, the power-law modulus theory and the yield modulus model. The tensile force method predicted considerably earlier transition than the dynamic methods, and the corresponding DSC data indicate relative crystallinity of larger than 0.2 at the transition times. The limitation of dynamic methods and other possible errors have been analyzed. While the dynamic methods are suitable for slow crystallization, the tensile force method is more appropriate for the crystallization of moderate rates. Moreover, it has the advantage of almost not disturbing the crystallizing materials before the transition.  相似文献   

20.
The effect of temperature on the solubility of ionic surfactants was interpreted in terms of standard enthalpy and entropy of dissolution at reference temperature by considering the change in the heat capacity. The significant value of the latter quantity causes the curvature of the function logarithm of equilibrium constant (or solubility) vs. the reciprocal thermodynamic temperature. The solubility data for several sodium n-alkylsulfonates, published by Saito, Moroi, and Matuura, were interpreted by nonlinear regression analysis. It was found that both the enthalpy and entropy of dissolution decrease with the chain length. The heat capacity increases in the course of the dissolution process.  相似文献   

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