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Evans WJ Yoo CS Lee GW Cynn H Lipp MJ Visbeck K 《The Review of scientific instruments》2007,78(7):073904
We have developed a unique device, a dynamic diamond anvil cell (dDAC), which repetitively applies a time-dependent load/pressure profile to a sample. This capability allows studies of the kinetics of phase transitions and metastable phases at compression (strain) rates of up to 500 GPa/s (approximately 0.16 s(-1) for a metal). Our approach adapts electromechanical piezoelectric actuators to a conventional diamond anvil cell design, which enables precise specification and control of a time-dependent applied load/pressure. Existing DAC instrumentation and experimental techniques are easily adapted to the dDAC to measure the properties of a sample under the varying load/pressure conditions. This capability addresses the sparsely studied regime of dynamic phenomena between static research (diamond anvil cells and large volume presses) and dynamic shock-driven experiments (gas guns, explosive, and laser shock). We present an overview of a variety of experimental measurements that can be made with this device. 相似文献
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Obituaries
Grigorii Valentinovich Samsonov 相似文献16.
In cancer cells, cell-surface sialylation is altered, including a change in oligo/polysialic acid (oligo/polySia) structures. Since they are unique and rarely expressed in normal cells, oligo/polySia structures may serve as promising novel biomarkers and targets for therapies. For the diagnosis and treatment of the disease, a precise understanding of the oligo/polySia structures in cancer cells is necessary. In this study, flow cytometric analysis and gene expression datasets were obtained from sixteen different cancer cell lines. These datasets demonstrated the ability to predict glycan structures and their sialylation status. Our results also revealed that sialylation patterns are unique to each cancer cell line. Thus, we can suggest promising combinations of antibody and cancer cell for glycan prediction. However, the precise prediction of minor glycans need to be further explored. 相似文献
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根据等效焓降法在热力系统计算时的特点,推导了循环函数法在回热系统中的局部定量计算方法,导出了回热系统局部定量计算的几个重要结论.最后,通过实例计算对所得结论进行了验证.验证结果表明,该方法在回热系统局部定量计算过程中具有简洁、准确、概念清晰等特点,适合推广. 相似文献
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Ken Naitoh 《Artificial Life and Robotics》2013,18(3-4):133-143
In the present report, we examine whether or not there are similar and different characteristics between biological molecular particles and non-living ones such as quark and leptons. While the Newton, Schrodinger, and Boltzmann equations and elementary particle theories describe only a narrow range of scales, the present statistic-fluid dynamic theory having only one arbitrary constant synthetically reveals masses as well as frequencies of various particles of quarks, leptons, W–Z bosons, Higgs boson, plank mass, hadrons, atoms, biological molecules, liquid droplets, living cells, biological organs, and stars. This is possible because each flexible particle is commonly generated by a mode in which a larger particle breaks up into two smaller ones through a gourd shape (gourdron) with two lumps rather than strings. These masses and frequencies dominated by the super-magic numbers, including the asymmetrically golden and symmetrically yamato ratios, can be derived by a quasi-stability principle weaker than neutral stability. The primordial mechanism underlying various types of symmetry breaking and the natural four forces including gravity is also revealed by this theory. 相似文献
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Wataru Tamura Arata Yasuda Ken Suto Masasuke Hosokawa Osamu Itoh Jun-Ichi Nishizawa 《Journal of Electronic Materials》2003,32(10):1079-1084
Effects of Bi doping in PbTe liquid-phase epitaxial layers grown by the temperature difference method under controlled vapor
pressure (TDM-CVP) are investigated. For Bi concentrations in the solution, xBi, lower than 0.2 at.%, an excess deep-donor level (activation energy Ed≈0.03–0.04 eV) appears, and Hall mobility is low. In contrast, for xBi>0.2 at.%, Hall mobility becomes very high, while carrier concentration is in the range of 1017 cm−3. Inductive coupled plasma (ICP) emission analysis shows that, for xBi=1 at.%, Bi concentration in the epitaxial layer is as high as NBi=2.3–2.7 × 1019 cm−3. These results indicate that Bi behaves not only as a donor but also as an acceptor, and the nearest neighbor or very near
donor-acceptor (D-A) pairs are formed, so that strong self-compensation of Bi takes place. Carrier concentration for highly
Bi-doped layers shows a minimum at a Te vapor pressure of 2.2 × 10−5 torr for growth temperature 470°C, which is coincident with that of the undoped PbTe. 相似文献