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991.
Recently, the researches of quantum group signature (QGS) have attracted a lot of attentions and some typical protocols have been designed for e-payment system, e-government, e-business, etc. In this paper, we analyze the security of the quantum group signature with the example of two novel protocols. It can be seen that both of them cannot be implemented securely since the arbitrator cannot solve the disputes fairly. In order to show that, some possible attack strategies, which can be used by the malicious participants, are proposed. Moreover, the further discussions of QGS are presented finally, including some insecurity factors and improved ideas.  相似文献   
992.
In this paper, we present a model describing the nonlinear dynamic visco-hyperelastic behaviors of dielectric elastomers (DE), with the purpose to explain the material’s dynamic energy dissipation mechanism, and provide convenience for actual design of DE devices. On the basic mechanical properties of the material, a visco-hyperelastic constitutive relationship, derived from Kelvin–Voigt rheological model and expressed as complex modulus, is created at first. Then, from the approximate relationship between harmonic motion frequency and the stretch rate (as well as the amplitude of stretch ratio) of the film, a new model-fitting approach is put forward to obtain the three intrinsic parameters, based on the uniaxial tensile tests for VHB 4910 DE film at different stretch rates (from 0.029 to 0.71 s?1). Applying the proposed parameters, the hysteresis and energy dissipation behaviors of the DE film are subsequently predicted, showing good agreement with the experimental results. Finally, the influences of the kinematic variable pair on energy dissipation properties are quantitatively investigated.  相似文献   
993.
Bian  Xintian  Zuo  Fen  Cheng  Ju 《Optical Review》2018,25(2):190-196
Optical Review - Traditional phase measurement profilometry adopts divergent illumination to obtain the height distribution of a measured object accurately. However, the mapping relation between...  相似文献   
994.
Unstable electrode/solid-state electrolyte interfaces and internal lithium dendrite penetration hamper the applications of solid-state lithium-metal batteries (SSLMBs), and the underlying mechanisms are not well understood. Herein, in situ optical microscopy provides insights into the lithium plating/stripping processes in a gel polymer electrolyte and reveals its dynamic evolution. Spherical lithium deposits evolve into moss-like and branch-shaped lithium dendrites with increasing current densities. Remarkably, the on-site-formed solid electrolyte interphase (SEI) shell on the lithium dendrite is distinctly captured after lithium stripping. Inducing an on-site-formed SEI shell with an enhanced modulus to wrap the lithium precipitation densely and uniformly can regulate dendrite-free behaviors. An in-depth understanding of lithium dendrite evolution and its functional SEI shell will aid in the optimization of SSLMBs.  相似文献   
995.
Fulvestrant (‘Faslodex’), an estrogen receptor antagonist, is available for the treatment of advanced breast cancer. The oil-based vehicle of Faslodex can lead to various adverse effects. A novel fulvestrant microcrystal (aqueous suspension) was developed in this study to eliminate these adverse effects. A sensitive and robust liquid chromatography tandem mass spectrometry method was developed and validated for the determination of fulvestrant in rat plasma using supported-liquid extraction. The separation of fulvestrant was achieved on an Agilent SB-C18 column (2.1 × 50 mm, 3.5 μm) with isocratic elution using fulvestrant-d3 as internal standard. Mass spectrometric detection was conducted in negative multiple reaction monitoring mode. Ion transitions were at m/z 605.5 → 427.5 for fulvestrant and m/z 608.5 → 430.5 for fulvestrant-d3. The excellent linearity was demonstrated over the range 0.05–100.0 ng/ml (r2 = 0.99). The lower limit of quantitation was 0.05 ng/ml, which was superior to that reported in literature The method validation was evaluated by selectivity, accuracy, precision, recovery and matrix effect in agreement with the US Food and Drug Administration guidance. The method was successfully applied to a pharmacokinetic study of a novel fulvestrant microcrystal in rats after intramuscular administration. It revealed that the rate of absorption increases and the extent of absorption is constant with a decrease in microcrystal diameter.  相似文献   
996.
Hu  Yiran  Zuo  Donghao  Zhang  Yaning  Xu  Fei  Li  Bingxi  Liang  Shuang 《Journal of Thermal Analysis and Calorimetry》2020,141(5):1529-1541
Journal of Thermal Analysis and Calorimetry - A stochastic growth method for generating the porous soil structure is proposed, and an enthalpy-based lattice Boltzmann phase transition model is...  相似文献   
997.
In this article, the authors introduce two operators-geometrical maximal operator Mo and the closely related limiting operator M0^*, then they give sufficient conditions under which the equality M0=MM0^* holds, and characterize the equivalent relations between the weak or strong type weighted inequality and the property of W∞-weight or W∞^*-weight for the geometrical maximal operator in the case of two-weight condition. What should be mentioned is that the new operator-the geometrical minimal operator is equal to the limitation of the minimal operator sequence, and the results for the minimal operator proved in [12] makes the proof elegant and evident.  相似文献   
998.
Three new phenolic glucosides named orcinosides A, B, and C ( 1, 2 , and 3 , resp.) were isolated in low yields (4.0×10−6, 11.5×10−6, 4.5×10−6%, resp.) from the rhizomes of Curculigo orchioides. Their structures were elucidated by comprehensive spectroscopic analyses including FAB‐MS, HR‐ESI‐MS, IR, and 1D‐ and 2D‐NMR (HSQC, HMBC) data. Compounds 1 – 3 contained two orcinol‐glucoside moieties linked through a CH2 group.  相似文献   
999.
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