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21.
介绍了一种简便易行的降低疏松固体物质冲击波温度的方法,其要点是用液体石蜡充填样品的空隙。以用粉末锐钛矿压装成型的样品为例,对比了不充填和充填液态石蜡时冲击波作用的结果。在同样的冲击加载条件下(均为钢飞片,撞击速度为3.16 km/s),估算两种样品中达到的压力分别为36.3 GPa和46.8 GPa,平均温度分别约为4.7×103 ℃和2.0×103 ℃,即:充填液态石蜡的样品中压力增加了约10 GPa,但平均温度降低了近3×103 ℃。对冲击后回收样品的分析结果表明,不充填石蜡样品的主要产物为金红石,即冲击波产生的高温起了主要作用。而充填液态石蜡时,主要生成β-TiO2高压相,即高压起了主要作用。 相似文献
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24.
Gorga MP Neely ST Kopun J Tan H 《The Journal of the Acoustical Society of America》2011,129(2):801-806
Distortion-product otoacoustic emissions (DPOAEs) were used to describe suppression growth in normal-hearing humans. Data were collected at eight f(2) frequencies ranging from 0.5 to 8 kHz for L(2) levels ranging from 10 to 60 dB sensation level. For each f(2) and L(2) combination, suppression was measured for nine or eleven suppressor frequencies (f(3)) whose levels varied from -20 to 85 dB sound pressure level (SPL). Suppression grew nearly linearly when f(3) ≈ f(2), grew more rapidly for f(3)?< f(2), and grew more slowly for f(3)?> f(2). These results are consistent with physiological and mechanical data from lower animals, as well as previous DPOAE data from humans, although no previous DPOAE study has described suppression growth for as wide a range of frequencies and levels. These trends were evident for all f(2) and L(2) combinations; however, some exceptions were noted. Specifically, suppression growth rate was less steep as a function of f(3) for f(2) frequencies ≤ 1 kHz. Thus, despite the qualitative similarities across frequency, there were quantitative differences related to f(2), suggesting that there may be subtle differences in suppression for frequencies above 1 kHz compared to frequencies below 1 kHz. 相似文献
25.
Using kinetic Monte Carlo method, we have simulated a pulsed energetic growth process in pulsed laser deposition. During the growth of film, substrate temperature mainly influences upon film morphology by directly enhancing the adatom mobility through the temperature-dependent thermal vibration. By contrast, the effect of incidence kinetic energy on film growth is complex resulting from the collisions between the incident particles and the adatoms. The results show that improving incident kinetic energy cannot significantly accelerate the migration rate of adatom but change surface microstructure and promote single adatom formation resulting in more island aggregation density. Moreover, since pulse-influx characterizes pulsed laser deposition, the intensity per pulse contributes to the evolvement of nucleation density and the results illustrate that a general scaling law different from ordinary power law still exists in energetic growth of pulsed laser deposition. 相似文献
26.
XiGuang Cao Xun Chen YunHua Chen XiangYi Cui DeQing Fang ChangBo Fu Karl L. Giboni HaoWei Gong GuoDong Guo Ming He Jie Hu XingTao Huang XiangDong Ji YongLin Ju ShaoLi Li Qing Lin HuaXuan Liu JiangLai Liu Xiang Liu Wolfgang Lorenzon YuGang Ma YaJun Mao KaiXuan Ni Kirill Pushkin XiangXiang Ren Michael Schubnell ManBing Shen YuJie Shi Scott Stephenson AnDi Tan Greg Tarlé HongWei Wang JiMing Wang Meng Wang XuMing Wang Zhou Wang YueHuan Wei ShiYong Wu MengJiao Xiao Xiang Xiao PengWei Xie Tao Ye YingHui You XiongHui Zen Hua Zhang Tao Zhang HaiYing Zhao Li Zhao XiaoPeng Zhou ZhongHua Zhu 《中国科学:物理学 力学 天文学(英文版)》2014,57(8):1476-1494
27.
We present a protocol for multi-party superdense coding
by using multi-atom in cavity quantum electrodynamics (QED).
It is shown that, with a highly detuned
cavity mode and a strong driving field, the protocol is insensitive
to both cavity decay and thermal field. It is even certain to
identify GHZ states via detecting the atomic states. Therefore we can
realize the quantum dense coding in a simple way in the multiparty
system. 相似文献
28.
Interfacial and electrical properties of HfAlO/GaSb metal-oxide-semiconductor capacitors with sulfur passivation 下载免费PDF全文
Interfacial and electrical properties of HfAlO/GaSb metal-oxide-semiconductor capacitors(MOSCAPs) with sulfur passivation were investigated and the chemical mechanisms of the sulfur passivation process were carefully studied. It was shown that the sulfur passivation treatment could reduce the interface trap density Ditof the HfAlO/GaSb interface by 35% and reduce the equivalent oxide thickness(EOT) from 8 nm to 4 nm. The improved properties are due to the removal of the native oxide layer, as was proven by x-ray photoelectron spectroscopy measurements and high-resolution cross-sectional transmission electron microscopy(HRXTEM) results. It was also found that GaSb-based MOSCAPs with HfAlO gate dielectrics have interfacial properties superior to those using HfO2 or Al2O3 dielectric layers. 相似文献
29.
We report, for the first time, an efficient intra-cavity second-harmonic generation (SHG) at 1084 nm in a nonlinear optical crystal, BiB3O6(BIBO) at the direction of (θ, ?) = (170.1°, 90°), performed with a LD end-pumped cw Nd:YVO4 laser. With 590 mW diode pump power, a continuous-wave (cw) SHG output power of 19 mW at 542 nm yellow-green color has been obtained using a 1.5 mm-thick BIBO crystal. The optical conversion efficiency was 3.22%. It was found that the output wavelength could be 532 nm, 537 nm or 542 nm according to regulating the angle of BIBO. 相似文献
30.
Stefaan J. Soenen Bella B. Manshian Abuelmagd M. Abdelmonem José‐María Montenegro Sisareuth Tan Lieve Balcaen Frank Vanhaecke Alain R. Brisson Wolfgang J. Parak Stefaan C. De Smedt Kevin Braeckmans 《Particle & Particle Systems Characterization》2014,31(7):794-800
Poly(ethylene glycol) (PEG) is frequently used to coat various medical nanoparticles (NPs). As PEG is known to minimize NP interactions with biological specimens, the question remains whether PEGylated NPs are intrinsically less toxic or whether this is caused by reduced NP uptake. In the present work, the effect of gold NP PEGylation on uptake by three cell types is compared and evaluated the effect on cell viability, oxidative stress, cell morphology, and functionality using a multiparametric methodology. The data reveal that PEGylation affects cellular NP uptake in a cell‐type‐dependent manner and influences toxicity by different mechanisms. At similar intracellular NP numbers, PEGylated NPs are found to yield higher levels of cell death, mostly by induction of oxidative stress. These findings reveal that PEGylation significantly reduces NP uptake, but that at similar functional (= cell‐associated) NP levels, non‐PEGylated NPs are better tolerated by the cells. 相似文献