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101.
102.
Compositional design of high modulus glasses for disk substrates   总被引:1,自引:0,他引:1  
Modified equations have been derived on the basis of Makishima–Machenzie (M–M) theory for direct determination of the elastic modulus of glasses from composition. This modified calculation model gives an excellent agreement between the measured and estimated values of elastic modulus for over 50 different glasses. Using this model we developed a glass in the Li2O–MgO–Al2O3–Y2O3–TiO2–SiO2 system with elastic modulus value greater than 130 GPa and bending strength higher than 50 kg f/mm2. This high modulus glass substrate is expected to provide a solution to the vibration problem of rapid rotation magnetic disk and allow higher track density per inch to be achieved for high performance hard-disk drives (HDDs).  相似文献   
103.
Morphologicaldeformationsofthemyceliaorconidiaofmicroorganismssuchascurling,swelling,hyper-divergence,beadformationandinhibitionofgermination,areofteninducedinthepresenceofbioactivesubstances".AnewscreeningbioassaymethodfordetectingthedeformationofmyceliagerminatedfromconidiaofPyriculartaoryzaeP-2bwasfirstdevelopedforthequantitativeapplicationtoscreeningantifungalandantineoplasticagentsbyH.Kobayashi'.Thisbioassayisquick,easytoperform,andhasbeenefficientlyusedinthepreliminaryscreeningofantineo…  相似文献   
104.
Single-crystal SnO2 nanorods were grown on rutile TiO2 with a heteroepitaxial relation of SnO2{001}/TiO2{001} (SnO2-NR#TiO2) by a hydrothermal reaction. Resulting compressive lattice strain in the SnO2-NR near the interface induces a continuous increase in the a-axis length extending over 60 nm to relax towards the [001] direction from the root to the tip. UV-light irradiation of the robust SnO2-NR#TiO2 stably progresses the selective oxidation of ethanol to acetaldehyde with an external quantum yield of 25.6 % at excitation wavelength (λex)=365 nm under ambient temperature and pressure. Spectroscopic analyses and density functional theory simulation results suggested that the extremely high photocatalytic activity stems from the smooth interfacial electron transfer from TiO2 to SnO2-NR through the high-quality junction and subsequent efficient charge separation due to the lattice strain-induced unidirectional potential gradient of the conduction band minimum in the SnO2-NR.  相似文献   
105.
Steroidal allylic alcohols formed Na+ adduct ion peaks [M+Na]+ by the addition of NaCl in FAB mass spectrometry. A comparison of the intensities of the adduct ion peaks of allylic alcohols with those of the corresponding saturated alcohols and olefin suggested that the olefinic double bond and the proximal hydroxyl group had coordinated to Na+. The adduct ion was stable and did not undergo dehydroxylation. We suggest that the Na+ adduction will be useful for the molecular weight determination of allylic alcohols which are susceptible to dehydroxylation under FAB mass spectrometric conditions. Na+ adduct ions of alpha,beta-unsaturated carbonyl compounds were also investigated.  相似文献   
106.
Various analogs of known immunomodulatory derivatives of thalidomide (1) (IMiDs: 3, 5) were synthesized, focusing on cell-differentiation-inducing, cyclooxygenase-inhibitory and anti-angiogenesis activities. Among the prepared compounds, NIDO-33 (14) showed cell differentiation-inducing activity on HL-60 cells and anti-angiogenic activity on human umbilical vein endothelial cells (HUVEC). AIDO-00 (7) also showed anti-angiogenic activity. NIDO-11 (8) showed an enhancing effect on all-trans retinoic acid (ATRA)-induced HL-60 cell differentiation, and AIDO-30 (13) exhibited cyclooxygenase (COX)-inhibitory activity.  相似文献   
107.
Mono- and dihydroxylated metabolites of thalidomide were efficiently prepared and characterized, and their inhibitory activity on tumor necrosis factor (TNF)-alpha production in the human monocytic leukemia cell line THP-1 was evaluated. 5,N-Dihydroxythalidomide was a much more potent TNF-alpha production inhibitor than thalidomide.  相似文献   
108.
A new type of defect-less, layered organo-titanosilicate is synthesized using a simple, template-free, evaporation-induced self-assembly process. The obtained layered material has superhydrophobicity and exhibits promising catalytic activity in the epoxidation of olefins using 30% H(2)O(2) aqueous solution as oxidant at room temperature.  相似文献   
109.
An explicitly correlated complete active space second-order perturbation (CASPT2-F12) method is presented which strongly accelerates the convergence of CASPT2 energies and properties with respect to the basis set size. A Slater-type geminal function is employed as a correlation factor to represent the electron-electron cusp of the wave function. The explicitly correlated terms in the wave function are internally contracted. The required density matrix elements and coupling coefficients are the same as in conventional CASPT2, and the additional computational effort for the F12 correction is small. The CASPT2-F12 method is applied to the singlet-triplet splitting of methylene, the dissociation energy of ozone, and low-lying excited states of pyrrole.  相似文献   
110.
The extended multireference quasi-degenerate perturbation theory, proposed by Granovsky [J. Chem. Phys. 134, 214113 (2011)], is combined with internally contracted multi-state complete active space second-order perturbation theory (XMS-CASPT2). The first-order wavefunction is expanded in terms of the union of internally contracted basis functions generated from all the reference functions, which guarantees invariance of the theory with respect to unitary rotations of the reference functions. The method yields improved potentials in the vicinity of avoided crossings and conical intersections. The theory for computing nuclear energy gradients for MS-CASPT2 and XMS-CASPT2 is also presented and the first implementation of these gradient methods is reported. A number of illustrative applications of the new methods are presented.  相似文献   
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