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An efficient method for calculating the Lagrange multipliers and the analytical gradients of one state included in a state average MCSCF wave function is presented. It is demonstrated that the state average energy of an ‘equal-weight’ scheme is invariant to rotations within the state average subspace and that the corresponding rotations should be eliminated from the Lagrangian equations. Finally, a diagnostic is presented, which gauges the energy difference between a state defined by a state average calculation and the corresponding fully variational multi-configurational SCF state. 相似文献
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ChemInform Abstract: X-Ray Structural Studies of the Polymorphic Elpasolites K2LiAlF6 and Rb2LiGaF6.
ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option. 相似文献
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Comparative study on structural and optical properties of CdS films fabricated by three different low-cost techniques 总被引:1,自引:0,他引:1
Highly crystalline and transparent cadmium sulphide films were fabricated at relatively low temperature by employing an inexpensive, simplified spray technique using perfume atomizer (generally used for cosmetics). The structural, surface morphological and optical properties of the films were studied and compared with that prepared by conventional spray pyrolysis using air as carrier gas and chemical bath deposition. The films deposited by the simplified spray have preferred orientation along (1 0 1) plane. The lattice parameters were calculated as a = 4.138 Å and c = 6.718 Å which are well agreed with that obtained from the other two techniques and also with the standard data. The optical transmittance in the visible range and the optical band gap were found as 85% and 2.43 eV, respectively. The structural and optical properties of the films fabricated by the simplified spray are found to be desirable for opto-electronic applications. 相似文献
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Sides CR Liyanage R Lay JO Philominathan ST Matsushita O Sakon J 《Journal of the American Society for Mass Spectrometry》2012,23(3):505-519
Pairing limited proteolysis and matrix-assisted laser desorption/ionization-time of flight mass spectrometry (MALDI-TOF MS)
to probe clostridial collagenase collagen binding domain (CBD) reveals the solution dynamics and stability of the protein,
as these factors are crucial to CBD effectiveness as a drug-delivery vehicle. MS analysis of proteolytic digests indicates
initial cleavage sites, thereby specifying the less stable and highly accessible regions of CBD. Modulation of protein structure
and stability upon metal binding is shown through MS analysis of calcium-bound and cobalt-bound CBD proteolytic digests. Previously
determined X-ray crystal structures illustrate that calcium binding induces secondary structure transformation in the highly
mobile N-terminal arm and increases protein stability. MS-based detection of exposed residues confirms protein flexibility,
accentuates N-terminal dynamics, and demonstrates increased global protein stability exported by calcium binding. Additionally,
apo- and calcium-bound CBD proteolysis sites correlate well with crystallographic B-factors, accessibility, and enzyme specificity.
MS-observed cleavage sites with no clear correlations are explained either by crystal contacts of the X-ray crystal structures
or by observed differences between Molecules A and B in the X-ray crystal structures. The study newly reveals the absence
of the βA strand and thus the very dynamic N-terminal linker, as corroborated by the solution X-ray scattering results. Cobalt
binding has a regional effect on the solution phase stability of CBD, as limited proteolysis data implies the capture of an
intermediate-CBD solution structure when cobalt is bound. 相似文献
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The thin-film spinel-forming solid state reaction between Al2O3 and MgO has been studied under initially non-coherent conditions. MgO films in (001) orientation on
-cut sapphire single crystals were heated at 1100°C for 30 min or 1h. The film/substrate reaction proceeds via cation counterdiffusion as was revealed by a marker experiment. The MgAl2O4 films formed were predominantly (001) oriented, with an additional systematic tilt of about 5° of the spinel lattice around the [010] axis. The structure of the Al2O3
/MgAl2O4(001) and MgAl2O4(001)/MgO(001) reaction fronts has been investigated on cross section samples by high-resolution electron microscopy. It appeared that after starting from an incoherent interface, the Al2O3
/MgAl2O4(001) front assumes an almost fully coherent structure during the reaction. As a result the lattice misfit is reduced to 1%, and interfacial ledges are formed. The latter most probably play an active role in the necessary c.p.h. f.c.c. reconstruction of the oxygen sublattice. The MgAl2O4(001)/MgO(001) reaction front consists of coherent regions divided by misfit dislocations. During the reaction the former run ahead whereas the latter lag behind. As a result the morphology of the reaction front is bowed. The results confirm earlier observations of Carter and Schmalzried of the semicoherent Al2O3(00.1)/CoAl2O4(111) interface, thus strongly supporting the conclusion of a fundamental new phase transformation mechanism specific to oxide systems.Presented at the workshop on High-Voltage and High-Resolution Electron Microscopy, February 21–24, 1994, Stuttgart, Germany. 相似文献
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RIVLIN T. J.; RUSCHEWEYH ST.; SHAFFER D.; WIRTHS K. J. 《IMA Journal of Numerical Analysis》1983,3(3):327-332
Given (1, 0), n N, we discuss the optimal recoveryof (), for analytic and bounded in < 1, from the knowledge of the values of at n points z1,.zm[0,l),where these points are chosen to produce the least possibleintrinsic error. The optimal algorithms are explicitly determined. 相似文献
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A FORTRAN computer program for automatic neutron activation analysis is presented. The program locates and identifies peaks
in a gamma-ray spectrum, calculates peak areas and the concentrations of the elements of interest in the sample. This program
was specifically designed for the SLOWPOKE reactor, it uses a semi-absolute method and does not need standards or flux monitors.
The program was written so as to minimize the computation time, and a typical 4096-channel spectrum is processed in five seconds
by an IBM 360/75 computer. 相似文献
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Nanocrystalline and transparent conducting SnO2‐ ZnO films were fabricated by employing an inexpensive, simplified spray technique using a perfume atomizer at relatively low substrate temperature (360±5 °C) compared with conventional spray method. The structural studies reveal that the SnO2‐ZnO films are polycrystalline in nature with preferential orientation along the (101) plane. The dislocation density is very low (1.48×1015lines/m2), indicating the good crystallinity of the films. The crystallite size of the films was found to be in the range of 26–34 nm. The optical transmittance in the visible range and the optical band gap are 85% and 3.6 eV respectively. The sheet resistance increases from 8.74 kΩ/□ to 32.4 kΩ/□ as the zinc concentration increases from 0 to 40 at.%. The films were found to have desirable figure of merit (1.63×10–2 (Ω/□)–1), low temperature coefficient of resistance (–1.191/K) and good thermal stability. This simplified spray technique may be considered as a promising alternative to conventional spray for the massive production of economic SnO2 ‐ ZnO films for solar cells, sensors and opto‐electronic applications. (© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献