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1.
乙二醇/水与丙三醇/水体系的焓浓图与(火用)浓图   总被引:1,自引:0,他引:1  
本文基于乙二醇/水与丙三醇/水两组二元体系在不同温度下的实验数据,对超额焓数据应用局部作用模型拟合,并分析拟合效果与拟合参数变化情况,发现Wilson模型拟合效果较好.通过Wilson方程的活度系数表达形式,推算了两组体系的气液平衡,并进而计算了两组体系的焓浓图与(火用)浓图.  相似文献   

2.
利用磷酸三丁酯形成的反胶束在常温常压下制备出一种超浓盐酸,其酸水摩尔比(nHCl/nH2O)在0.50~1.50之间,高于常温常压下饱和浓盐酸的酸水摩尔比(0.28)。红外光谱的研究结果表明超浓盐酸中部分氯化氢未发生电离,而是以分子形式存在。同时HCl参与了体系内氢键网络的形成。超浓盐酸体系提供了一个特殊的物理化学环境,使得溶于其中的铜离子呈红棕色。采用FTIR及UV-Vis对含铜离子的超浓酸体系进行了表征。结果表明,超浓酸中,铜离子的d—d跃迁和电荷迁移跃迁谱带都发生了明显的变化。铜离子的加入对超浓盐酸体系中未电离的HCl分子的氢键体系产生明显影响。  相似文献   

3.
α-Fe粉体浓悬浮体系的制备及磁流变效应   总被引:2,自引:0,他引:2       下载免费PDF全文
报道使用价格低廉的还原铁粉制备磁性粒子浓悬浮体系 ,对体系磁流变效应进行研究 ,并研究了磁性颗粒尺寸和氧化物对悬浮体系力学性质及沉降稳定性的影响 .  相似文献   

4.
报道一种新的磁性粒子浓悬浮体系沉降稳定性的表征方法。对均匀分散的磁性粒子浓悬浮体系,采用定时光度测量法对其沉降稳定性进行表征,可以得到一定时间内粒子沉降的定量数据。此方法可用于低体积分散磁流变液沉降稳定性的表征。同时,对比分析表明,在磁性粒子浓悬浮体系中加入纳米级TiO2粒子,能使制备的磁流变液稳定性显著增强。  相似文献   

5.
不少作者对常用工质绘制过(火用)焓图。本文利用Oguchi等人提出的状态方程,算出并绘制了R 22(火用)焓图(SI制),并给出两种不同环境温度时使用本图的(火用)修正曲线。 一、R22(火用)焓图的编制 R 22(火用)焓图以稳定流动系统工质比焓(火用)e为纵坐标,以比焓h为横坐标。焓(火用)e的定义式为  相似文献   

6.
钟诚  陈智全  杨伟国  夏辉 《物理学报》2013,62(21):214207-214207
本文利用相位调制光纤低相干动态光散射装置, 研究了不同物质量浓度下电解质 (NaCl及 BaCl2) 对浓悬浮液中聚苯乙烯胶体颗粒扩散特性的影响. 实验结果表明, 当电解质浓度低于0.01 mol/L 时, 恒温条件下浓悬浮液中聚苯乙烯胶体颗粒扩散系数随电解质离子浓度以及离子化合价的增大而增大, 实验测量得到的扩散系数与Stern模型所得到的扩散系数符合较好. 关键词: 测量 电解质 浓悬浮液 低相干动态光散射  相似文献   

7.
中心遮拦干涉图的处理   总被引:4,自引:1,他引:3  
张圣华  张晓辉 《光学学报》1998,18(10):404-1407
介绍了一种用于中心遮拦的大口径干涉仪的干水条纹处理软件,该软件通过对干涉数据进行采集,处理而得出被检波面的波差分布和像差,由于对干涉图数据拟合过程中所使用的泽尼特(Zernike)多项式进行了修正,因此得到的结果的准确度也有了较大的提高。  相似文献   

8.
首次建立了光声门图数学模型。以相乘同态信号模型和对声带振动的研究结果为基础,提出、研究并实现了光声门图信号数字处理。仪器使用结果表明,光声门图技术对喉科学、艺术嗓音、语言学、语音声学及语言信号数字处理等领域具有广泛和重要的应用价值。  相似文献   

9.
本文针对高浓度散射介质,用低相干光纤动态光散射技术测量浓悬浮液中多分散颗粒系的粒径及其粒径分布。利用迭代CONTIN算法对实验数据进行反演运算,得到多分散颗粒系的粒径分布结果。结果表明,浓悬浮液中多分散颗粒系的峰值粒径测量值与给定的两种标准粒径值相吻合,其误差在4%之内,粒径分布曲线中各散射颗粒所反映的散射体光强分布与根据Mie散射计算得到的理论值相吻合。实验结果证明低相干光纤动态光散射实验系统能准确测量浓悬浮液中多分散颗粒粒径及粒径分布。  相似文献   

10.
本文通过静态法高压汽液相平衡装置测定了温度293.15~353.15 K,压力0.1~2.1 MPa条件下R152a-DMF体系的汽液相平衡数据。采用逸度系数法中的PR、SRK状态方程,活度系数法中的NRTL、Wilson模型分别对该体系的汽液相平衡实验数据进行了关联计算,结果表明,Wilson模型能更好地描述该体系在实验温度、压力下的汽液相平衡数据。  相似文献   

11.
本文介绍了一种实现Logistic映射分岔图局部放大的计算机模拟方法,对Logistic映射分岔图上任意局部范围可实现10。以上的放大,便于观察Logistic映射分岔图混沌区内的精细结构,该方法实现的计算机模拟过程响应速度快,可实时产生Logistic模型分岔图局部放大的计算机模拟图像,适合于课堂教学计算机模拟实时演示.  相似文献   

12.
We calculate the ground state phase diagrams of a mixed Ising model on a square lattice where spins S (± 3/2, ± 1/2) in one sublattice are in alternating sites with spins Q (± 5/2, ± 3/2, ± 1/2), located on the other sublattice. The Hamiltonian of the model includes first neighbor interactions between the S and Q spins, next-nearest-neighbor interactions between the S spins, and between the Q spins, and crystal field. The topologies of the phase diagrams depend on the values of the parameters in the Hamiltonian. The diagrams show some key features: coexistence between regions, points where two, three, four, five and six states can coexist. Besides being very useful as a way to check the low temperature limit of the finite-temperature phase diagram, often obtained by mean-field theories, the richness of the ground state diagrams for certain combinations of parameters can be used as a guide to explore interesting regions of the finite-temperature phase diagram of the model.  相似文献   

13.
应用卡诺循环的Bucher图形象地表示出三热源循环,并由图中的相似三角形直接导出三热源循环的能量守恒方程、熵守恒方程和性能系数.  相似文献   

14.
The isotropic liquid (I) ⊥ nematic (N) ⊥ smectic A(A) phase diagrams of homologous series of liquid crystals obtained experimentally may be divided into at least 4 types (Fig. la-d) according to the characteristic behavior of TNI.  相似文献   

15.
界面有序单分子层膜结构的红外和拉曼光谱表征   总被引:2,自引:0,他引:2  
本文综述了近十几年来红外和拉曼光谱方法用于表征空气/水界面单分子层(Langmiur膜)、油/水界面和空气/固界面单分子层(LB膜)分子结构的最新进展。  相似文献   

16.
We calculate the dynamic phase transition (DPT) temperatures and present the dynamic phase diagrams in the kinetic mixed spin-1/2 and spin-5/2 Ising model under the presence of a time-dependent oscillating external magnetic field. We employ the Glauber transition rates to construct the set of mean-field dynamic equations. The time variation of the average magnetizations and the thermal behavior of the dynamic magnetizations are investigated, extensively. The nature (continuous or discontinuous) of the transitions is characterized by studying the thermal behaviors of the dynamic magnetizations. The DPT points are obtained and the phase diagrams are presented in two different planes. Phase diagrams contain four fundamental phases and three coexistence or mixed phases, which strongly depend on interaction parameters. The phase diagrams are discussed and a comparison is made with the results of the other mixed spin Ising systems.  相似文献   

17.
The critical behaviors of the trilayer Bethe lattice in the form of spin-(1/2,3/2,1/2) with the exterior two layers consisting of spin-1/2 and the interior one having only spin-3/2 Ising spins are studied in terms of the recursion relations with either ferromagnetic or antiferromagnetic bilinear exchange interactions between the nearest-neighbor spins. The ground-state phase diagrams are calculated and it is found that the model presents six different ground state phase configurations. The thermal variations of the order-parameter and free energy are investigated, therefore, topologically different phase diagrams of the model are obtained. It is found that the model exhibits second- and first-order phase transitions, tricritical and bicritical points for the values of the coordination numbers q=3, 4 and 6 and, the reentrant behavior for q=4 and 6, respectively.  相似文献   

18.
J. Alejandre 《Molecular physics》2013,111(23-24):3029-3033
The surface properties and phase diagrams are examined for a number of modified water models. In the ‘bent’ family of models where the bond angle is decreased and the network structure is lost the surface tension is lower than in SPC/E water and the critical temperature is lower. In the ‘hybrid’ family of models which are hybrids between SPC/E water and a Lennard–Jones liquid the surface tension and the critical temperature are higher that in SPC/E water. These properties correlate well with the varying ability of the liquids to dissolve hard spheres. The surface potential, on the other hand, is slightly smaller in magnitude in the hybrid models than in SPC/E water because there is slightly less alignment of the dipoles in the surface layer. The degree of molecular alignment in the surface and the consequent surface potential drop is much lower in magnitude in the bent models than in SPC/E water.  相似文献   

19.
A bilayer spin-1/2 Ising model consisting of two superposed Bethe lattices with antiferromagnetic/ferromagnetic interactions is studied by the use of exact recursion relations in a pairwise approach in the presence of an external staggered magnetic field. Besides the ground state phase diagrams calculated in different possible planes of the model parameters space, the thermal variations of the order-parameters and the free energy are investigated to obtain the temperature-dependent phase diagrams of the model for different values of the coordination numbers q. Our calculations reveal that depending on the strength of the model parameters, the model exhibits a variety of interesting phase transitions and therefore phase diagrams.  相似文献   

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