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81.
82.
The single crystals of the superconducting Li0.2(1)ZrNCl have been derived from the single crystals of β-ZrNCl by intercalation of lithium using an n-butyllithium solution in hexane. The crystal structure has been refined on the basis of the single-crystal X-ray data: the space group R-3m, a=3.591(1) Å, c=27.839(6) Å, Z=6, R1=0.0749 for 196 reflections and 12 variables. β-ZrNCl is isotypic with SmSI, while the structure of Li0.2(1)ZrNCl can be described as the Li intercalated YOF type, a stacking variant of the SmSI type. The tightly bound slabs with a Cl-Zr-N-N-Zr-Cl sequence of close-packed layers are stacked rhombohedrally along the c-axis, with the van der Waals gaps between the chlorine layers hosting Li ions. This is the first single-crystal study on the Li intercalated phase. The structural changes from the pristine single crystals were precisely determined. 相似文献
83.
Martin Hoefling Francesco Iori Dr. Stefano Corni Dr. Kay‐Eberhard Gottschalk Dr. 《Chemphyschem》2010,11(8):1763-1767
The interactions of amino acids with inorganic surfaces are of interest for biologists and biotechnologists alike. However, the structural determinants of peptide–surface interactions have remained elusive, but are important for a structural understanding of the interactions of biomolecules with gold surfaces. Molecular dynamics simulations are a tool to analyze structures of amino acids on surfaces. However, such an approach is challenging due to lacking parameterization for many surfaces and the polarizability of metal surfaces. Herein, we report DFT calculations of amino acid fragments in vacuo and molecular dynamics simulations of the interaction of all amino acids with a gold(111) surface in explicit solvent, using the recently introduced polarizable gold force field GolP. We describe preferred orientations of the amino acids on the metal surface. We find that all amino acids preferably interact with the gold surface at least partially with their backbone, underlining an unfolding propensity of gold surfaces. 相似文献
84.
Mizoshita N Yamanaka K Shimada T Tani T Inagaki S 《Chemical communications (Cambridge, England)》2010,46(48):9235-9237
Polycondensation of 9-mesityl-10-methylacridinium-bridged organosilane in the presence of a nonionic surfactant yielded a mesostructured organosilica solid with a functional framework that exhibited long-lived photoinduced charge separation. 相似文献
85.
The coupled equations which describe the temporal evolution of the Bose–Einstein condensed system are derived in the framework of nonequilibrium Thermo Field Dynamics. The key element is that they are not the naive assemblages of assumed equations, but are the self-consistent ones derived by appropriate renormalization conditions. While the order parameter is time-dependent, an explicit quasiparticle picture is constructed by a time-dependent expansion. Our formulation is valid even for the system with a unstable condensate, and describes the condensate decay caused by the Landau instability as well as by the dynamical one. 相似文献
86.
87.
Taku Saiki Kazuo Imasaki Chiyoe Yamanaka Masahiro Nakatsuka 《Optics Communications》2006,268(1):155-159
We observed the lasing of highly sensitized Nd/Cr:YAG ceramic disks that use artificial solar radiation pumping. The disk material can be used for high power multi-stage amplifiers pumped by lamplight or sunlight because of its scalability and ability to handle high power densities. A maximum output power of 86 mW was experimentally obtained, and this value correlated well with the calculated results. A small signal gain of 1.9 was obtained, and the estimated stored energy was 0.6 J/cm3, which is three or four times higher than that from a Nd:YAG medium. 相似文献
88.
This paper presents the results of an investigation on the effects of measurement volume size on the mean velocity profile and the Reynolds stress for fully developed turbulent pipe flows. The study employs the ultrasonic velocity profile method, which is based on the ultrasonic Doppler method. The ultrasonic Doppler method offers many advantages over conventional methods for flow rate measurement in the nuclear power plant piping system. This method is capable of measuring the instantaneous velocity profile along the measuring line and is applicable for opaque liquids and opaque pipe wall materials. Furthermore, the method has the characteristic of being non-intrusive. Although it is applicable to various flow conditions, it requires a relatively large measurement volume. The measurement volume of the present method has a disk-shape determined by the effective diameter of the piezoelectric element and the number of the wave cycles of the ultrasonic pulse. Considering this disk-shaped measurement volume and expressing the time-averaged velocity in a truncated Taylor series expansion around the value at the center of the measuring control volume, the value of the velocity can be obtained. The results are then compared with the data obtained from DNS and LDA measurements. The result shows that the effect of the measurement volume size appears in the buffer region and viscous sublayer. 相似文献
89.
Back Cover: CH Activation Generates Period‐Shortening Molecules That Target Cryptochrome in the Mammalian Circadian Clock (Angew. Chem. Int. Ed. 24/2015) 下载免费PDF全文
Tsuyoshi Oshima Dr. Iori Yamanaka Dr. Anupriya Kumar Dr. Junichiro Yamaguchi Dr. Taeko Nishiwaki‐Ohkawa Kei Muto Rika Kawamura Dr. Tsuyoshi Hirota Prof. Dr. Kazuhiro Yagita Prof. Dr. Stephan Irle Prof. Dr. Steve A. Kay Prof. Dr. Takashi Yoshimura Prof. Dr. Kenichiro Itami 《Angewandte Chemie (International ed. in English)》2015,54(24):7200-7200
90.
Frontispiece: Entropy‐Driven 1,2‐Type Friedel–Crafts Reaction of Phenols with N‐tert‐Butoxycarbonyl Aldimines 下载免费PDF全文