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1.
The third-order optical nonlinearity in carbon nanotubes (CNT) exposed to an intensive external electromagnetic field has been investigated. The analysis is based on the quantum kinetic equations for the density matrix of π-electrons in CNT. In the regime of weak driving field, the kinetic equations have been solved by the perturbation method and the third-order nonlinear polarizability of different achiral CNTs has been calculated. The theory elaborated has been used for the evaluation of nonlinear susceptibility of CNT-based composites. Comparison with available experimental data has been presented. In the case of high intensive driving field a nonperturbative numerical simulation of the process has been carried out in the time domain. The axial current density in CNT has been calculated. Excitation of π-plasmons in CNTs has been analyzed.  相似文献   

2.
综述了镁在有机合成中的应用研究,从镁在元素周期表的位置和电子构型详细讲述了镁作为催化剂和格氏试剂对有机合成的影响。催化剂从催化活性物质,催化剂载体,助催化剂的角度进行论述,格氏试剂主要论述了典型的反应类型,最后对镁在有机合成中的应用进行了展望。  相似文献   

3.
油田含油污水过滤器滤料原位清洗再生   总被引:2,自引:0,他引:2  
通过分析发现滤料污染物主要成分为原油、硫化物等。针对污染物成分研制了有效的滤料再生剂,很好地解决了致密的混合污染物层难以清除的问题。研制了加药装置,确定了滤料原位再生工艺,现场应用取得了良好的效果。  相似文献   

4.
Amorphous poly(ethylene terephthalate) (PET)/nanotalc nanohybrids have been prepared through solution casting route. The fine dispersion of nanotalc clay in the polymer matrix has been examined through transmission electron microscopy (TEM). The intercalation and interaction of nanoclay have further been confirmed using X-ray diffraction, ultraviolet, and Fourier transform infrared techniques. The thermal stability has been tested via thermogravimetric analysis and nanohybrids have been found thermally stable. The glass-transition temperature has been further confirmed through DTA and differential scanning calorimetry analysis which has been increased in the presence of nanotalc arising from greater interaction. The nanohybrids have been tested for their mechanical performances and have been found to have improved mechanical responses for nanotalc-filled nanohybrids. The modulus has been increased whereas toughness has been compromised meagerly. The modulus values have been theoretically predicted using various micromechanical models. The microhardness of the nanohybrids has been examined through Vicker hardness test. The theoretical prediction of the hardness values has been done using different micromechanical models. The structural development upon uniaxial stretching of the samples has been studied using small-angle X-ray scattering and wide-angle ray diffraction. The stretched samples have found to have short-range ordering as well as increased blob size and better coherency in the presence of nanotalc. The aspect ratio has been increased upon stretching. The inclusion of nanotalc has induced high barrier for gas permeation as compared to pure PET. The oxygen transmission rate has been found to decrease up to 64% for 8 wt % of filler concentration. The prediction of the permeability data has been done using different models considering different aspect ratios. The permeability values have been predicted very closely and nanohybrids have been found suitable for practical applications such as packaging. © 2020 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 137, 48607.  相似文献   

5.
The statistical theory of phase transition in fullerides of alkali metals to the superconducting state has been elaborated. The calculation of the free energy of crystals has been performed on the basis of molecular-kinetics and the equilibrium equations have been examined. The critical temperature of superconductivity has been estimated, and its concentration dependence has been ascertained. The calculation results have been compared with experimental data. The numerical estimation for energetic parameters of pairing of Cooper pairs electrons has been performed.  相似文献   

6.
胜利油田临盘采油厂目前开发动用临盘、商河、临南三个油田,区域构造位于渤海湾盆地济阳坳陷惠民凹陷中央隆起带。“九五”末期由于油田相继进入特高含水期,剩余油分布复杂、断块破碎、油水井套损严重、注采完善程度低,造成油田产量连续三年下降。针对严峻的开发形势,进入“十五”以后,通过深化油藏构造、储层、剩余油潜力的研究,强化注采井网的完善。提高了水驱控制程度,增强油田稳产基础,提高采收率。全厂连续三年原油年产量连续稳定在163×104t,取得较好的开发效果和经济效益。  相似文献   

7.
露天矿连续工艺系统设备可靠性分析   总被引:2,自引:0,他引:2  
针对黑岱沟露天煤矿第一套连续工艺系统长期达不到设计生产能力的问题,对系统中的设备进行了可靠性数据的收集与分析,计算了各台设备的可靠性指标,找出了系统的薄弱环节,并提出了提高设备可靠性的措施.  相似文献   

8.
The separation and recovery of radiostrontium from simulated alkaline reprocessing waste solution has been studied using Amberlite IRC‐718, a chelating resin containing iminodiacetic acid groups. The breakthrough behavior of strontium has been determined by conducting an extended column run. The column loading performance has been correlated with batch equilibration results. Efficient elution of loaded strontium has been achieved using dilute nitric acid. Satisfactory column performance has been demonstrated in repeated loading‐elution‐regeneration cycles. Finally, the characteristics of used resin have been determined to ascertain its efficacy for further use.  相似文献   

9.
接枝改性淀粉作为LLDPE/淀粉共混体系增容剂的研究   总被引:4,自引:0,他引:4  
采用接枝改性淀粉作为LLDPE/淀粉共混体系增容剂,对其单体作用和与接枝改性PE配合作用的增容效果进行了研究,发现配合作用增容效果比较明显,体系拉伸强度可达9.77MPa,伸长率为128%,并在此基础上进一步考察了偶联淀粉与LLDPE共混的效果。  相似文献   

10.
梁旭 《河北化工》2010,33(7):9-10,13
简述了甲苯液相氧化制苯甲醛的工艺过程,详细介绍了苯甲醛在生产过程中存在的产品质量问题、影响因素,并提出了解决方案及优化过程,从而使苯甲醛产品纯度从99%提高到99.5%,优级品率达到95%以上。  相似文献   

11.
The liquid phase backmixing has been reduced significantly by introducing horizontal perforated sieve plates into a 6.2 cm diameter and 77 cm height and in a 20 cm diameter and 90 cm height bubble columns. For the visbreaking operation of the petroleum residue, where the bubble column is used as soaker such a sectionalization has been suggested. The effect of the introduction of different gas quantities at various axial locations has also been studied to check the effect of increasing gas quantity formed in the visbreaking operation. The nonideality in the liquid phase backmixing has been studied by measuring liquid phase RTD and analysed by using one parameter dispersion model. A new parameter FP (flow parameter) has been defined and a correlation to predict liquid phase dispersion coefficient has been developed which covers the entire range of variables used in the present work.  相似文献   

12.
空气管道出口处负压现象的发现,打破了传统的空气管道终端压力分布理论,改变了人们长期形成的风机出口管道终端不会出现负压的观念.在阐明风机全压基本概念及其用途的基础上,着重从条件和原因方面,分析管道出口处出现负压的机理,并得出几点重要的结论.  相似文献   

13.
《国际聚合物材料杂志》2012,61(14):1130-1146
The present paper investigates the interaction of silica filler in uncompatibilized and compatibilized styrene butadiene rubber/nitrile rubber (SBR/NBR) blends of varying compositions. The use of a dynamic mechanical analyzer as a tool for confirming the compatibility by the addition of dichlorocarbene modified styrene butadiene rubber (DCSBR) in these blends has been described. The addition of silica in uncompatibilized as well as compatibilized blends has been found to be increasing the rheometric-processing characteristics such as maximum viscosity and rate of cure. The magnitude of these values has been found to be higher for compatibilized blends and for 50/50 composition. The optimum cure time has been found to be decreasing with silica loading regardless of the presence of the compatibilizer. The magnitude of optimum cure time has been found to be higher for uncompatibilized system and for the composition with higher SBR content. Enhancement in mechanical properties with the addition of silica has been observed for compatibilized blends, more intensely than uncompatibilized samples. A good correlation between mechanical properties and solvent sorption behavior has also been observed.  相似文献   

14.
基于ANSYS的复合材料旋翼桨叶动力分析   总被引:3,自引:0,他引:3  
首次应用APDL语言建立复合材料旋翼桨叶三维有限元模型。计入空气动力和离心力,应用ANSYS软件对旋翼桨叶的动力特性和静强度进行分析,给出桨叶共振图。依据本文动力分析后设计的复合材料旋翼桨叶已成功应用于某型号的无人直升机。  相似文献   

15.
针对壳聚糖生产中存在的问题,对原生产工艺进行改进,使之减少了化工原料的用量,缩短了生产周期,降低了生产成本。同时,从环境保护入手,对生产中产生的废液综合治理,回收废液中的蛋白质作为优质饲料添加剂,不仅解决了壳聚糖生产的环境保护难题,而且变废为宝,提高了经济效益。  相似文献   

16.
ABSTRACT: In the article photoacoustic effect in nano-composite structure "porous silicon - liquid" has been investigated. Process of photoacoustic signal formation in such structures experimentally has been examined. Liquids with different viscosity (ethanol, acetone) as fillers have been used. Mathematical model of photoacoustic signal formation corresponded with experiment has been proposed. The role of thermal induced pressures of liquid in the pores on the photoacoustic signal formation based on this model has been analyzed.  相似文献   

17.
高浓度超稠油乳化废水预处理工艺与实践   总被引:2,自引:1,他引:1  
超稠油在加工过程中产生大量高浓度乳化废水,常规炼油污水处理场难以处理并导致外排水严重超标.以某稠油加工企业高浓度超稠油乳化废水为研究对象,对其物理化学性质,沉降、破乳、絮凝条件进行了系统研究,并在大量试验的基础上开发出预处理工艺.相应装置建成后运行平稳高效,废水得到高效的处理与污油资源回收.  相似文献   

18.
A simplified and unified model has been proposed to study the cavitation phenomena in hydraulic devices, with emphasis on the venturi tube and high-speed homogenizer. A turbulence model analogous to the acoustic cavitation has been developed and the dynamics of the cavities as a cluster has been considered. The prediction of the cavitation inception number has been made for various operating conditions and has been compared with the experimental observations. The effect of operating parameters, such as inlet pressure and fully recovered downstream pressure, has been studied numerically and compared with the data in the literature for the case of the venturi. The predicted cavitation intensities were compared indirectly with the experimental results. It has been found that optimum operating conditions do exist at which the observable cavitational effect is maximum. In the case of the high-speed homogenizer, the predicted effects as a function of rotational speed have been compared with the results of the aqueous KI decomposition reaction and have been found to match well. The study concludes with the recommendations and methods for possibly optimizing hydrodynamic cavitation phenomena for maximum effect.  相似文献   

19.
郑志刚 《山东化工》2014,(3):137-139
立式热虹吸再沸器由于其具有较大的传热系数、较小的占地面积以及安装便捷等优点,在化工行业中得到广泛的应用,本文利用HTRI软件对醋酸仲丁酯装置中醋酸精馏塔再沸器进行设计优化,计算合适的再沸器结构参数,找出合适的静压头,以及最优的进口管径。  相似文献   

20.
The mathematical model of the separation of granular materials on multiple-deck sieve classifiers has been constructed using the theory of Poisson processes and the model has been identified. The problem of the optimal implementation of the process in multicriterial setting has been formulated and solved; the engineering simulation of the classifier has been performed using this solution.  相似文献   

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