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弱相互作用二元混合液中的声速计算 总被引:1,自引:0,他引:1
本文在给出超额摩尔绝热压缩系数计算公式的基础上,给出了弱相互作用液体混合物的声速计算公式。对36组弱相互作用二元混合液进行了声速值的计算,结果表明计算值与实验值符合很好,并讨论了二元混合液中声速出现极小值的现象。 相似文献
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用非线性自陷方程的动力学理论计算了水分子、液体水和水蒸汽等的OH和HOH键的非线性振动的量子振动能谱,所得结果与实验值符合得较好,也比简正模式和局域模式的结果较好.
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通过自行研制的光纤传感器对不同黏度液体中材料靶后的力学作用进行研究,获得了液体黏度变化对等离子体烧蚀力、射流冲击力及空泡生存周期的影响. 实验结果表明:液体黏度相同时,靶材所受冲击力幅值随作用激光能量的增加单调上升;液体黏度增加时,靶材所受的冲击力减小,靶材的空化空蚀程度亦减小;受液体黏度增大的影响,空泡膨胀或收缩过程减缓,相应的生存周期也增大. 此外,对空泡溃灭周期公式进行修正, 结果表明修正后的理论估算值与实验值的一致性较好. 相似文献
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在室温条件下, 利用金刚石对顶砧超高压技术, 对氨的半水合物(2NH3·H2O) 进行了原位高压拉曼光谱研究, 采用红宝石荧光压标测压, 实验的最高压力为41.0 GPa。装入金刚石对顶砧样品腔的初始样品为液态的氨的半水合物, 当压力达到3.5 GPa时, 显微镜下观察到整个样品腔内均匀的出现块状晶体, 同时, 测量到的拉曼谱上出现许多新的拉曼峰。因此, 我们判断在此压力下液态的2NH3·H2O发生了液固相变。当压力增加到19.0 GPa左右时, 2NH3·H2O的拉曼频移随压力变化的曲线有拐点, 并且具有软化特性的N-H伸缩振动模式消失。我们分析这是因为在高压下, 通过O-H…N成键的II型氨分子发生了旋转, 所以2NH3·H2O在此压力下发生了一次固固相变。 相似文献
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A Novel Approach for Introducing Bio-Materials Into Cells 总被引:1,自引:0,他引:1
A novel approach was developed to introduce biological materials into cells for gene transfection and gene therapy applications. The method is based on the technique of electrospraying bio-materials into cells. A prototype apparatus was constructed for a feasibility study. The features of the gene transfector include: (1) A dual-capillary assembly to spray suspensions of biological materials. The outer capillary provided sheathing liquid that controlled the charge level on individual particles without altering the properties of suspensions. (2) An air–CO2 gas mixture was used for suppressing possible corona discharge and kept the same gas composition as those in incubators. (3) The designed chamber enabled the spray to operate at reduced pressure for increasing sprayed particle velocity. In the feasibility study, both suspensions of plasmid and plasmid-coated gold particles were used. The plasmid used was the commercially available Enhanced Green Fluorescent Protein gene. COS-1 cells were used as the target and the liquid media was evacuated immediately prior to the spraying process. Electrospraying was conducted at ambient pressure and the duration was no more than 2 min. After the spray transfection, the media was immediately replaced and the cell samples were returned to the incubator for 36 h. Transgene expression was detected by cellular fluorescence. This technology promises to have great potential for gene transfection and therapy studies. 相似文献
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Muhtar Ahart Amol Karandikar Stephen Gramsch Reinhard Boehler Russell J. Hemley 《高压研究》2013,33(3):327-336
The properties of solid and liquid phases of H2O at high pressure and temperature remain an active area of research. In this study, Brillouin spectroscopy has been used to determine the temperature dependence of sound velocities in H2O as a function of pressure up to 26 GPa through the phase field of ice VII and into the liquid to a maximum temperature of 1200 K. The Brillouin shift of the quasi-longitudinal acoustic mode moves to lower frequencies upon melting at each pressure. As a test of the method, measurements of the melting of Ar by Brillouin scattering at several pressures show a similar behavior for the acoustic mode, and measured melting points are consistent with previous results. The results of H2O melting are consistent with previously reported melting curves below 20 GPa. The data at higher pressure indicate that ice melts at a higher temperature than a number of previous studies have indicated. 相似文献
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Starr FW Bellissent-Funel MC Stanley HE 《Physical review. E, Statistical physics, plasmas, fluids, and related interdisciplinary topics》1999,60(1):1084-1087
We use molecular-dynamics simulations to study the effect of temperature and pressure on the local structure of liquid water in parallel with neutron-scattering experiments. We find, in agreement with experimental results, that the simulated liquid structure at high pressure is nearly independent of temperature, and remarkably similar to the known structure of the high-density amorphous ice. Further, at low pressure, the liquid structure appears to approach the experimentally measured structure of low-density amorphous ice as temperature decreases. These results are consistent with the postulated continuity between the liquid and glassy phases of H2O. 相似文献
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The calculation of the equilibrium constants K of the sonolysis reactions of CO2 into CO and O atom, the recombination of O atoms into O2 and the formation of H2O starting with H and O atoms, has been studied by means of statistical thermodynamic. The constants have been calculated at 300 kHz versus the pressure and the temperature according to the extreme conditions expected in a cavitation bubble, e.g. in the range from ambient temperature to 15200 K and from ambient pressure to 300 bar. The decomposition of CO2 appears to be thermodynamically favored at 15200 K and 1 bar with a constant K1=1.52 x 10(6), whereas the formation of O2 is not expected to occur (K2=1.8 x10(-8) maximum value at 15200 K and 300 bar) in comparison to the formation of water (K3=3.4 x 10(47) at 298 K and 300 bar). The most thermodynamic favorable location of each reactions is then proposed, the surrounding shell region for the thermic decomposition of CO2 and the wall of the cavitation bubble for the formation of water. Starting from a work of Henglein on the sonolysis of CO2 in water at 300 kHz, the experimental amount of CO formed (7.2 x 10(20)molecules L(-1)) is compared to the theoretical CO amount (1.4 x 10(27)molecules L(-1)) which can be produced by the sonolysis of the same starting amount CO2. With the help of the literature data, the number of cavitation bubble has been evaluated to 6.2 x 10(15) bubbles L(-1) at 300 kHz, in 15 min. This means that about 1 bubble on 1900000 is efficient for undergoing the sonolysis of CO2. 相似文献
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本文研究测量了Ammoeng 100与其水溶液在不同压力环境下的红外光谱,以期了解该离子液体与水之间的相互作用.结果表明,Ammoeng 100与水之间的相互作用主要来自离子液体的阴离子与水分子,且两者会根据能量稳定性而有选择性的接近;相对于阴离子,Ammoeng 100的烷基链受D_2O的扰动不大.与纯Ammoeng 100相比,在Ammoeng 100/D_2O的红外光谱中显示烷基C-H伸缩振动频率并没有太大变化,而压力小于1.0 GPa时D_2O会造成在Ammoeng 100的S=O对称伸缩振动频率红移.压力大于1.0GPa时,纯Ammoeng 100与Ammoeng 100/D_2O中的S=O对称伸缩振动频率大同小异,表明高压环境下D_2O不会对阴离子的对称伸缩振动频率造成明显影响,同时也显示离子液体在极性区的缔合结构会受到高压的扰动而有显著变化. 相似文献
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Federica Venturini Sebastian Schöder Werner F. Kuhs Veijo Honkimäki Louis Melesi Harald Reichert Helmut Schober Frederic Thomas 《Journal of synchrotron radiation》2011,18(2):251-256
A cell for the investigation of interfaces under pressure is presented. Given the pressure and temperature specifications of the cell, P≤ 100 bar and 253 K ≤T≤ 323 K, respectively, high‐energy X‐rays are required to penetrate the thick Al2O3 windows. The CH4(gas)/H2O(liquid) interface has been chosen to test the performance of the new device. The measured dynamic range of the high‐energy X‐ray reflectivity data exceeds 10?8, thereby demonstrating the validity of the entire experimental set‐up. 相似文献
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A Videographic Study of Dynamic Phase Separation for Immiscible Solutions under Acoustic Levitation Condition 下载免费PDF全文
《中国物理快报》2016,(12)
The transparent aqueous solutions of succinonitrile(SCN) provide an effective model system to simulate the phase separation process of various advanced materials.Here we report a real-time and in-situ study of phase separation dynamics for the SCN-15%H_2O,SCN-48%H_2O and SCN-70%H_2O solutions implemented by high-speed CCD videography together with acoustic levitation technique.It is found that liquid phase separation induces an unsteady state of drop rotation under levitated conditions.The resultant centrifugal force plays the dominant role in the migration of secondary liquid globules.The most desirable homogeneously dispersive structures can only be derived from the earlier stage of phase separation,whereas three kinds of macrosegregation are always the finally stable structure patterns.The migration velocity of minor liquid phase displays the nonlinear feature owing to the variations of globule location and centrifugal force.The surface tensions and volume fractions of immiscible phases also show a conspicuous influence upon the evolution dynamics of separation morphology. 相似文献