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941.
Ren Xiaoming Duan Chunying Zhu Huizhen Meng Qingjin Hu Chuanjiang Lu Changsheng Liu Yongjiang 《Transition Metal Chemistry》2001,26(3):295-299
Interesting complexes containing a mnt2– bridge, based on the reaction of [M(mnt)2]2– [M = Ni or Cu] with [Cu(LH)]+, have been prepared and characterized by e.s.m.s., i.r and u.v–vis. spectroscopic techniques and by electrochemistry. The complexes show weak antiferromagnetic interactions between magnetic centers. The X-ray analysis of the molecular structure of [Cu(LH)]2[Ni(mnt)2] has been completed. It structurally features the CN group of mnt2– which can act as a bridging ligand between two transition metals. 相似文献
942.
943.
The problem of a Griffith crack in an unbounded orthotropic functionally graded material subjected to antipole shear impact was studied. The shear moduli in two directions of the functionally graded material were assumed to vary proportionately as definite gradient. By using integral transforms and dual integral equations, the local dynamic stress field was obtained. The results of dynamic stress intensity factor show that increasing shear moduli’s gradient of FGM or increasing the shear modulus in direction perpendicular to crack surface can restrain the magnitude of dynamic stress intensity factor. 相似文献
944.
4th-order spline wavelets on a bounded interval 总被引:1,自引:0,他引:1
IntroductionWaveletanalysishasexperiencedanenormousdevelopmentinrecentyears.Oneoftheimportantfieldsisthenumericalanalysisofdifferentialequations.Theadvantageofadoptingwaveletshasbeenreported[1~ 4].Classicalapproachestowaveletconstructiondealwithmultireso… 相似文献
945.
946.
947.
D. Y. Pan D. R. Yuan H. Q. Sun S. Y. Guo X. Q. Wang X. L. Duan C. N. Luan Z. F. Li 《Crystal Research and Technology》2006,41(3):236-238
A study of growth of barium hydrogen phosphate (BaHPO4) crystal from solution is reported. The raw materials of barium hydrogen phosphate were successfully synthesized through chemical reaction in water. The solubility in HCl and H3PO4 solution were studied. It increased when acid concentration and temperature become higher, and the fitted curve of solubility is nearly a line. The acid concentration affects crystalline morphology of BaHPO4 crystal. The crystallization is well when the acid solution ranges from 0.5 to 0.8M. © 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim 相似文献
948.
In this paper, the Fisher equation is analysed. One of its travelling wave solution
is obtained by comparing it with KdV--Burgers (KdVB) equation. Its amplitude, width
and speed are investigated. The instability for the higher order disturbances to the
solution of the Fisher equation is also studied. 相似文献
949.
Xinyi Li Zengxin Qi Duan Ni Shaoyong Lu Liang Chen Xiangyu Chen 《Molecules (Basel, Switzerland)》2021,26(18)
Mutations in leucine-rich repeat kinase 2 (LRRK2) are recognized as the most frequent cause of Parkinson’s disease (PD). As a multidomain ROCO protein, LRRK2 is characterized by the presence of both a Ras-of-complex (ROC) GTPase domain and a kinase domain connected through the C-terminal of an ROC domain (COR). The bienzymatic ROC–COR–kinase catalytic triad indicated the potential role of GTPase domain in regulating kinase activity. However, as a functional GTPase, the detailed intrinsic regulation of the ROC activation cycle remains poorly understood. Here, combining extensive molecular dynamics simulations and Markov state models, we disclosed the dynamic structural rearrangement of ROC’s homodimer during nucleotide turnover. Our study revealed the coupling between dimerization extent and nucleotide-binding state, indicating a nucleotide-dependent dimerization-based activation scheme adopted by ROC GTPase. Furthermore, inspired by the well-known R1441C/G/H PD-relevant mutations within the ROC domain, we illuminated the potential allosteric molecular mechanism for its pathogenetic effects through enabling faster interconversion between inactive and active states, thus trapping ROC in a prolonged activated state, while the implicated allostery could provide further guidance for identification of regulatory allosteric pockets on the ROC complex. Our investigations illuminated the thermodynamics and kinetics of ROC homodimer during nucleotide-dependent activation for the first time and provided guidance for further exploiting ROC as therapeutic targets for controlling LRRK2 functionality in PD treatment. 相似文献
950.
Density and impurity profile behaviours in HL-2A tokamak with different gas fuelling methods 下载免费PDF全文
The electron density profile peaking and the impurity accumulation
in the HL-2A tokamak plasma are observed when three kinds of
fuelling methods are separately used at different fuelling particle
locations. The density profile becomes more peaked when the
line-averaged electron density approaches the Greenwald density limit
nG and, consequently, impurity accumulation is often
observed. A linear increase regime in the density range ne<
0.6nG and a saturation regime in ne > 0.6nG
are obtained. There is no significant difference in achieved density
peaking factor fne between the supersonic molecular beam
injection (SMBI) and gas puffing into the plasma main chamber.
However, the achieved fne is relatively low, in particular,
in the case of density below 0.7nG, when the working
gas is puffed into the divertor chamber. A discharge with a
density as high as 1.2nG, i.e. ne = 1.2nG,
can be achieved by SMBI just after siliconization as a wall
conditioning. The metallic impurities, such as iron and chromium,
also increase remarkably when the impurity accumulation happens. The
mechanism behind the density peaking and impurity accumulation is
studied by investigating both the density peaking factor versus the
effective collisionality and the radiation peaking versus density
peaking. 相似文献