石英晶体板非线性高频振动的拓展伽辽金法分析

针对考虑几何和材料非线性的石英晶体板厚度剪切振动和弯曲振动的方程组,利用扩展伽辽金法对该方程组进行转化和求解,分别获得了强烈耦合的厚度剪切振动模态和弯曲振动模态的频率响应关系,绘制了不同振幅比和不同驱动电压影响下的频率响应曲线图。数值计算结果表明可以选取石英晶片的最佳长厚比尺寸来避免两种模态的强烈耦合。驱动电压的变化将引起石英晶体谐振器厚度剪切振动频率的明显改变,必须将振动频率的漂移值控制在常用压电声波器件的允许值之内。扩展伽辽金法对石英晶体板非线性振动方程组的求解为非线性有限元分析和偏场效应分析奠定了基础。     

COMPENSATING ROLE OF SELF-EQUILIBRATED STRESS FIELDS IN CONSTRUCTING NON-SINGULAR SOLUTIONS USING A NON-EUCLIDEAN CONTINUUM MODEL FOR AN INCOMPRESSIBLE SPHERE

Journal of Applied Mechanics and Technical Physics - A self-equilibrated stress field for an incompressible sphere is constructed based on a non-Euclidean continuum model. The...     

CdS/Si nanofilm heterojunctions based on amorphous silicon films:Fabrication,structures,and electrical properties

Shortening the distance between the depletion region and the electrodes to reduce the trapped probability of carriers is a useful approach for improving the performance of heterojunction.The CdS/Si nanofilm heterojunctions are fabricated by using the radio frequency magnetron sputtering method to deposit the amorphous silicon nanofilms and Cd S nanofilms on the ITO glass in turn.The relation of current density to applied voltage(I-V)shows the obvious rectification effect.From the analysis of the double logarithm I-V curve it follows that below~2.73 V the electron behaviors obey the Ohmic mechanism and above~2.73 V the electron behaviors conform to the space charge limited current(SCLC)mechanism.In the SCLC region part of the traps between the Fermi level and conduction band are occupied,and with the increase of voltage most of the traps are occupied.It is believed that Cd S/Si nanofilm heterojunction is a potential candidate in the field of nano electronic and optoelectronic devices by optimizing its fabricating procedure.     

LWE from non-commutative group rings

Designs, Codes and Cryptography - The Learning-With-Errors (LWE) problem (and its variants including Ring-LWE and Module-LWE), whose security are based on hard ideal lattice problems, has proven to...     

Stability of Multiplier Ideal Sheaves

Chinese Annals of Mathematics, Series B - In the present article, the authors find and establish stability of multiplier ideal sheaves, which is more general than strong openness.     

季铵盐改性蒙脱石的制备与表征

采用十六烷基三甲基氯化铵(CTAC)对钠基蒙脱石(MMT)进行季铵化改性,制备有机蒙脱石(CMMT),对改性后的蒙脱石进行X射线衍射(XRD)、电位分析法(PA)、红外光谱(FT-IR)和热分析(TGA)等分析表征,并用改性后的蒙脱石吸附五氟尿嘧啶(5-FU)后测定并比较其载药量.结果表明,改性剂已成功插入到蒙脱石的层间;相比于钠基蒙脱石,有机蒙脱石的层间距和热稳定性均有所增大;当制备季铵盐有机改性蒙脱石时,反应温度为80℃,且CTAC的用量是MMT的2.5倍阳离子交换容量时,形成的有机蒙脱石的阳离子化程度和对5-FU的载药量最高.此外,考察并比较了有机蒙脱石和钠基蒙脱石的体外细胞毒性,结果显示有机蒙脱石具有更好的生物相容性和更低的细胞毒性.     

Development of Lysosome-Targeted Fluorescent Probes for Cys by Regulating the Boron-dipyrromethene (BODIPY) Molecular Structure

Our previous discovery suggested that substituents on the 1,7 positions delicately modulate the sensing ability of the meso-arylmercapto boron-dipyrromethene (BODIPY) to biothiols. In this work, the impact of delicate modulations on the sensing ability is investigated. Therefore, 1,7-dimethyl, 3,5-diaryl substituted BODIPY is designed and developed and its conformationally restricted species with a meso-arylmercapto moiety ( DM-BDP-SAr and DM-BDP-R-SAr ) as selective fluorescent probes for Cys. Moreover, the lysosome-target probes ( Lyso-S and Lyso-D ) based on DM-BDP-SAr carrying one or two morpholinoethoxy moieties were developed. They were able to detect Cys selectively in vitro with low detection limits. Both Lyso-S and Lyso-D localized nicely in lysosomes in living HeLa cells and exhibited red fluorescence for Cys. Moreover, a novel fluorescence quenching mechanism was proposed from the calculations by density functional theory (DFT). The probes may go through intersystem crossing (from singlet excited state to triplet excited state) to result in fluorescence quenching.     

Anti-Staphylococcus aureus evaluation of gallic acid by isothermal microcalorimetry and principle component analysis

Journal of Thermal Analysis and Calorimetry - The emergence of antibiotic-resistant Staphylococcus aureus requires new antibacterial drugs. In this study, using a thermal activity monitor air...     

Preparation and Characterization of a π-Conjugated Donor–Acceptor System Containing the Strongly Electron-Accepting Tetraphenylborolyl Unit

A novel thiophene-bridged donor–acceptor system was synthesized with a carbazole as donor and a borole as acceptor unit. The borole group was successfully installed via the tin–boron exchange reaction of 1,1-dimethyl-2,3,4,5-tetraphenylstannole with 9-(5-(dibromoboryl)thiophen-2-yl)carbazole. The effect of the borole on the optoelectronic properties of the donor–acceptor system was explored by spectroscopic (UV/Vis and fluorescence spectroscopy), electrochemical (cyclic voltammetry) and theoretical (TD-DFT) methods as well as by modifying its structure. The corresponding donor–acceptor compound bearing the widely employed dimesitylboryl acceptor group was also synthesized for comparison.