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191.
Guangying Lv 《Applicable analysis》2017,96(16):2737-2757
In this paper, we study the existence and uniqueness of strong solutions for stochastic partial functional differential equations with locally monotone coefficients, locally Lipschitz non-linearity, and time delay. Our results extend previous results obtained by Liu–Röckner, Caraballo et al. and Taniguchi et al. Examples are given to illustrate the wide applicability of our results. 相似文献
192.
本文引入了两类具有六个同构块的苯系异构物,每类包含八个本质不同的异物构物,我们能够依据于它们所含克勒结构数目对这八个异构物勒结构数目对这八个异构物进行全序比较。 相似文献
193.
本文通过将高阶非线性自治微分方程转化为Lurie型控制系统的方法,借助于Popov的频率判据,得到了它们全局渐近稳定的判别准则,推广了文[1]的结果. 相似文献
194.
王传芳 《浙江大学学报(理学版)》1986,13(3):258-267
1.引言 众所周知,人们对主型方程,即无重实特征的线性偏微分方程,已有了很好的了解,而对远较主型方程复杂得多的具重特征方程却认识得较少,目前大体上还只停留在个别例子的水平上。грушпн,в.в.首先举例指出重特征方程在解的光滑性问题中有所谓离散现象,即方程中的参量取一些离散的例外值时,解突然失去了光滑性。接着Treves,F.在类似的例子中发现了这种离散现象也出现在Cauchy问题解的唯一性问题中,王光寅等对Treves例子的离散现象作了进一步的深刻揭示。Menikoff,A.曾讨论了以下Treves例子为特例的更广泛一类的重特征方程 相似文献
195.
本文对羟乙芦丁在玻碳电极上的阳极微分脉冲安行为进行了研究,发现在Na2HPO4溶液中(pH=8.95)于+0.64V(vs.Ag/AgCl)左右产生一个良好的阳极氧化伏安峰,浓度在5~60mg/L之间与峰电流呈线性关系,不需分离直接测定了片剂中的羟乙芦丁含量。电极反应为扩散速率控制的不可逆可程。 相似文献
196.
M.D. Gil García F. Cañada Cañada M.J. Culzoni L. Vera-Candioti G.G. Siano H.C. Goicoechea M. Martínez Galera 《Journal of chromatography. A》2009,1216(29):5489-5496
An analytical method for the simultaneous determination of seven non-steroidal anti-inflammatory drugs (naproxen, ketoprofen, diclofenac, piroxicam, indomethacin, sulindac and diflunisal) and the anticonvulsant carbamazepine in river and wastewater is reported. The method involves pre-concentration and clean-up by solid-phase microextraction using polydimethylsiloxane/divinylbenzene fibers, followed by liquid chromatography with diode array detection analysis. Owing to the fact that river water samples did not contain interferences and no sensitivity changes due to sample matrix were observed, external calibration was implemented. Standardization was also applied in order to carry out the prediction step by preparing only two diluted standards that were subjected to the pre-concentration step and a set of standards prepared in solvent. For the analysis of wastewater samples, in contrast, it was necessary to implement standard addition calibration in combination with the multivariate curve resolution-alternating least squares (MCR-ALS) algorithm, which allowed us to overcome matrix effect and exploit the second order advantage. Recoveries ranging from 72% to 125% for all pharmaceuticals proved the accuracy of the proposed method in river water samples. On the other hand, wastewater sample recoveries ranged from 83% to 140% for all pharmaceuticals, showing an acceptable performance – considering this sample contains no modeled interferences. 相似文献
197.
The ground state ab initio CCSD(T) potential curves using various basis sets (aug-cc-pVXZ-PP (X = D, T, Q, 5)) is obtained for the dimers of helium with IIb group metals. The effect of the position of the (mid) bond-functions on the interaction energy is discussed. A Symmetry Adapted Perturbation Theory decomposition of the interaction energy is provided and the trends in the dimer stabilizing and destabilizing contributions are depicted. The spline fitted potential curves are applied together with rigorous statistical formulae in order to obtain the transport coefficients (viscosity coefficients, diffusion coefficients) and the second virial coefficient both for pure constituents and mixtures. The obtained theoretical results are compared with available experimental data. Molecular dynamics is used to obtain reliable values of the diffusion coefficients for all the systems under study. 相似文献
198.
199.
Ziauddin Ahmed Carsten Müller Jaya J. Johnston Kevin Nguyen Christopher P. J. Schubert Karina Abitaev 《Liquid crystals》2019,46(6):896-904
We investigate the origins of ‘de Vries-like’ liquid crystalline behaviour by introducing an ethynyl spacer in the core of the tricarbosilane-terminated 5-phenylpyrimidine mesogens QL16-6 and QL17-6. The rationale for this structural change is based on the assumption that an ethynyl spacer would create more free volume in the core sub-layer and therefore decrease the orientational order parameter S2 in the SmA phase. The tricarbosilane-terminated mesogens WL41-5 and WL42-6 with a 5-(phenylethynyl)pyrimidine core in either a normal or inverted orientation were synthesised, and their mesomorphic and ‘de Vries-like’ properties characterised using polarised optical microscopy, differential scanning calorimetry, birefringence measurements, small–angle (SAXS) and 2D X-ray scattering. Reduction factors R derived from SAXS and optical tilt angle measurements suggest that neither WL41-5 (R = 0.49) nor WL42-6 (R = 0.80) exhibit ‘de Vries-like’ properties. The S2(T) profiles show an increase in orientational order with decreasing temperature and a sharp discontinuity at the SmA-SmC transition, which is consistent with ‘de Vries-like’ behaviour. However, the Leff(T) profiles suggest an increase in interdigitation that reduces the positive effect of increasing S2 in compensating for the molecular tilt. 相似文献
200.
Jieni Li Henan Li Lai Liu Huizhen Yao Bingbing Tian Chenliang Su Haizhe Zhong Ye Wang Lifu Zhang Yumeng Shi 《化学:亚洲杂志》2019,14(16):2861-2868
Organometallic halide perovskites have attracted great research interest as light‐active materials for use in optoelectronics. Here, we report a high‐performance photoconductor based on a methylammonium lead iodide (MAPbI3) film that was prepared from a methylamine‐treated MAPbI3/PbI2 perovskite film. An ultrahigh responsivity of 3.6 A W?1 and detectivity of 5.4×1012 Jones were obtained for the film under 0.5 mW cm?2 white‐light illumination. In addition, under 420 nm light irradiation, the film exhibited its highest responsivity and detectivity of 30 A W?1 and 2.4×1014 Jones, respectively. The excellent photo‐response performance results from the improved electronic quality and suppressed nonradiative recombination channels of the treated perovskite thin film. 相似文献