In situ X-ray diffraction investigation of compression behavior in Gd40Y16Al24Co20 bulk metallic glass under high pressure with synchrotron radiation

The compression behavior of the heavy RE-based BMC Gd40Y16Al24Co20 under high pressure has been investigated by in situ high pressure angle dispersive X-ray diffraction measurements using synchrotron radiation in the pressure range of 0-33.42 GPa at room temperature. By fitting the static equation of state at room temperature, we find the value of bulk modulus B is 61.27±4 GPa which is in good agreement with the experimental study by pulse-echo techniques of 58 GPa. The results show that the amorphous structure in the heavy RE-based BMG Gd40Y16Al24Co20 keeps quite stable up to 33.42 GPa although its compressibility is as large as about 33%. The coexistence of normal local structure similar to that of other BMGs and covalent bond structure similar to those of oxide glasses may be the reason for the anomalous property under high pressure of the Gd4oY16Al24Co2o BMG.     

Phase Transition and EOS of Cinnabar （α-HgS） at High Pressure and High Temperature

Phase relations and equation of state （EOS） of natural cinnabar （α-HgS） are investigated by high-pressure and high-temperature synchrotron x-ray powder diffraction. The unambiguous cinnabar-rocksalt structure phase boundaries are determined to be PI （GPa）=15.54- 0.014T（℃） and Pupper（GPa）= 23.84- 0.014T（℃） at 300-623K. With K1 fixed at 4, we obtain K0 = 37（4） GPa, （aK/aT）p= -0.025（2） GPaK-1, and α0 = 3.79（20） × 10-5 K-1 for the cinnabar phase of α-HgS. The （aK/aT）p and α0 of cinnabar phase are obtained for the first time. A nearly isotropic compression of cinnabar phase is observed by linear regressions.     

动态Dilaton-Maxwell黑洞的广义Stefan-Boltzmann定律

利用动态Dilaton-Maxwell黑洞视界面附近的熵密度,导出黑洞的瞬时辐射流量,得到了任一时刻黑洞沿某一方向的瞬时辐射流量总是正比于在该方向上黑洞事件视界温度的四次方的结论. 导出的广义Stefan-Boltzmann系数不再是一个恒量,而是一个与黑洞视界面附近的时空度规、黑洞视界的变化率及黑洞的吸收与辐射系数有关的动比例系数.揭示了黑洞周围的引力场与其热辐射之间存在着必然的内在联系. 关键词： 熵密度 薄膜模型 瞬时辐射流量 广义Stefan-Boltzmann系数     

NiO的高压结构和等温状态方程研究

 运用金刚石对顶砧（Diamond Anvil Cell,DAC）技术,以液氩作为传压介质,在最高压力为67 GPa的压力范围内对NiO进行了原位的同步辐射X射线衍射研究。在整个实验过程中,并未发现第一类结构相变,也没有发现T.Sasaki等预测的在60 GPa左右轴比c/a随压力的变化率而突然增大的现象,且此压力范围内NiO的结构畸变程度随压力的变化趋势相比以前的研究结果要平缓一些。用三阶的Brich-Murnaghan方程对实验数据进行拟合,得到的体弹模量及其对压力的一阶导数分别为B₀=195(4) GPa和B₀′=5.3(2)。     

Photoacoustic and Fluorescence Spectroscopy of Metallomesogens Containing Lanthanide Ions

制备了稀土液晶配合物Ln(bta)3L2 (Ln3+：La3+,Eu3+,Ho3+;L：N-octadecyl-2-hydroxy-4-tetradec-yloxybenzaldimine;bta：benzoyltrifluoroacetonate), 所得配合物在室温下呈近晶相(SmA phase)．首次利用光声光谱对金属液晶配合物的光谱性质、弛豫过程和相变进行研究．在配体吸收处,光声强度依Eu(bta)3L2相似文献   

高压下Sr2FeMoxNb1-xO6 (x=0, 0.3)的电学性质和结构稳定性

 采用金刚石压砧高压装置，研究了双钙态矿结构化合物Sr₂FeNbO₆及其掺杂物Sr₂FeMo_0.3Nb_0.7O₆在室温下，20 GPa内电阻和电容随压力的变化，并发现Sr₂FeNbO₆在7.5 GPa左右压力下发生了相变，而Sr₂FeMo_0.3Nb_0.7O₆的相变发生在2.8 GPa左右。并结合这两个样品的高压下的同步辐射能散X射线衍射实验，进一步证明了这两种相变是电子结构相变引起的。     

大功率全钒液流储能电池的研究

电力的供应紧张已成为制约我国国民经济稳定、可持续发展的瓶颈。电力系统对大规模储能技术提出了现实需求。同时，基于可再生能源发电的分布式供能技术将成为我国能源领域的发展重点。可再生能源（如风能、太阳能等）发电具有不稳定和不连续的间歇性特点，需要开发和建设配套的储能电池来保证发电和供电的连续和平稳。因此，高效率、大功率、大容量的电能存储技术是实现我国能源可持续发展的关键技术之一。     

IgA肾病免疫吸附剂的研究(Ⅰ)

本文采用碳酰二咪唑（N，N'-Carbonyldiimidazole,CDI)为活化剂^[1]，活化琼脂糖载体，并以人免疫球蛋白G（IgG)，为配基制成的免疫吸附剂首次探讨了对高IgA肾病病人血清进行体外清除IgA的实验，吸附率为30－35％，具有一定的清除效果。     

Development of pressure-modulated EXAFS method

Many modulation techniques have been widely applied to improve the quality of conventional spectra. Here a pressure-modulated EXAFS method is proposed to detect the small changes of local structure induced by the modulation of high pressure. In the experiment a dynamic diamond anvil cell was used to put a periodic load on the sample and lock-in amplifier to measure the modulated EXAFS signals. We have applied this technique to ZnSe and revealed a sensitivity to atomic displacement of 0.1 pm that is about ten times better than that of traditional EXAFS.     

Phase Relations and Pressure-Volume-Temperature Equation of State of Galena

The phase relations and pressure volume dependences of galena （PbS） under high pressure and high temperature are investigated by means of in situ observation using resistance heating in a diamond anvil cell and synchrotron radiation. The phase transition from NaCl type to TII type takes place at approximately 2.4 GPa. A fit to the high temperature third-order Bireh-Murnaghan equation of state yields an isothermal bulk modulus Ko = 37（3） GPa, and its pressure derivative K＇0 = 3.6（3）, the temperature derivative of the bulk modulus （ K/ T）p = -0.022（9） GPaK^-1, and the thermal expansion coeffeient α0 = 2.2（5） × 10^-5 K^-1 for TII-type galena. The linear compressibilities j3 along a, b and c directions of TII type is elastically anisotropic （βa = 3.4 × 10^-3 GPa^-1, βb = 1.4× 10^-4 GPa^-1 and βc = 1.6 × 10^-3 GPa^-1）. We obtain the temperature derivative of the bulk modulus （ K/ T）p and thermal expansion coefficient α0 for TlI-type galena for the first time.