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991.
The catalytic characteristics of horse liver alcohol dehydrogenase (HLADH) in the systems involving ionic liquids (ILs) (BMIm·Cl, BMIm·Br, BMIm·PF6, BMIm·BF4 BMIm·OTf and EMIm·Cl) were examined. HLADH displayed higher oxidation activity towards ethanol in the systems containing BMIm·Cl, BMIm·Br, EMIm·Cl or BMIm·PF6 with proper content than that in the IL-free buffer. An excessive amount of these ILs in the reaction systems resulted in an obvious decline in enzymatic activity. BMIm·BF4 and BMIm·OTf of any content investigated could considerably inhibit the enzyme. The anions of ILs showed significant effect on the activity, kinetic parameters and activation energy of HLADH-mediated ethanol oxidation. Additionally, BMIm·Cl, BMIm·Br, EMIm·Cl and BMIm·PF6 boosted markedly the thermostability of HLADH, while the enzyme was less thermostable in BMIm·BF4 or BMIm·OTf-containing systems. The associated conformational changes in HLADH caused by ILs were examined by UV technique. 相似文献
992.
ZHENG Chun-Long 《理论物理通讯》2003,40(7)
In this work, we reveal a novel phenomenon that the localized coherent structures of some (2 1 )-dimensionalphysical models possess chaotic and fractal behaviors. To clarify these interesting phenomena, we take the (2 1)-dimensional modified dispersive water-wave system as a concrete example. Starting from a variable separation approach,a general variable separation solution of this system is derived. Besides the stable localized coherent soliton excitationslike dromions, lumps, rings, peakons, and oscillating soliton excitations, some new excitations with chaotic and fractalbehaviors are derived by introducing some types of lower dimensional chaotic and fractal patterns. 相似文献
993.
Double barrier resonant tunneling diode using annealing induced diffusion modified quantum well is proposed as a viable alternative
to that using parabolic quantum well which requires complex techniques to fabricate it. The transmission coefficients are
calculated using the hybrid incremental airy function plane wave approach. The room temperature current-voltage characteristics
have been calculated using transmission coefficients. The current-voltage characteristics are found to be similar in both
diodes. 相似文献
994.
Jiayin Qin Xingshi Zheng Xiao Huang Hui Dai Xizhang Luo Yikun Lin 《International Journal of Infrared and Millimeter Waves》1997,18(6):1285-1297
Based on the quantum mechanics theory of density matrix and the principle of multiple-beam interference, the tuning characteristics
of optically pumped NH3 FIR lasers were studied. A series of metallic mesh Fabry-Perot cavity lasers with sample tubes of 10cm, 20cm and 100cm in
length were constructed and operated successfully, and the FIR laser spectra of the NH3 cavity lasers pumped by a TEA-CO2 laser were measured.
Supported by the Natural Sciences Foundation of Guangdong Province, PRC 相似文献
995.
本文讨论具非光滑特征的二阶椭圆偏微分算子Cauchy问题的唯一性.借用测不准原理的思想,通过将方程的解的精细微局部分解,把唯一性证明中最关键的Carleman估计在微局部的层次展开,从而可以在相差一个低阶项的意义下“凝固”某些奇异点的系数,克服因非光滑特征带来的困难,在较以往文章更一般的条件下证明了二阶椭圆微分算子Cauchy 问题的唯一性. 相似文献
996.
此文考虑了一类Moran分形,在其生成过程中每一阶的压缩比及压缩比的个数可以是不相同的,证明了支撑在此类Moran分形上的Moran测度的L^q-谱的存在性. 相似文献
997.
Incommensurate quantum systems with two competing periodicities exhibit metallic (with Bloch-type extended wave functions),
insulating (with exponentially localized wave functions) as well ascritical (with fractal wave functions) phases. An exact renormalization method, which takes into account the inherent incommensurability,
is used to obtain the phase diagram of various quantum models for the two-dimensional electron gas and for quantum spin chains
in a magnetic field. In this approach, the scaling properties of the fractal eigenstates are characterized by a fixed point
or a strange invariant set of the renormalization flow. One of our novel results is the existence of self-similar fluctuations
in the localized states once the exponentially decaying envelope is factorized out. In almost all cases under investigation
here, the universality classes can be broadly classified as those of the nearest-neighbor square or triangular lattices. 相似文献
998.
阐述了利用细菌视紫红质薄膜(BR薄膜)优良的非线性光学特性作为光寻址的空间光调制器的实验研究.BR有两个重要的光敏中间态(B态和M态),其吸收带(B态吸收峰为570nm,M态吸收峰为412nm)重叠区域较少,利用其正向(B→M)和逆向(M→B)光反应之间转化关系和B态与M态的差异吸收实现了相干光学图像到非相干光学图像的转换实验.采用经基因改性的细菌视紫红质薄膜(BRD96N)材料,使用670nm相干光作为写入光,530nm非相干光作为读出光,得到了分辨率约为200 lines/mm,对比度约为2.1∶1的
关键词:
光寻址空间光调制器
细菌视紫红质薄膜(BR薄膜)
非线性光学特性
相干光与非相干光图像相互转换 相似文献
999.
1000.
V. V. Zharinov 《Theoretical and Mathematical Physics》2008,157(3):1694-1706
In the framework of the algebraic geometric approach to differential-difference equations, we study symmetries and conservation
laws of evolutionary systems on multidimensional lattices. We describe conservation laws in terms of their characteristics.
__________
Translated from Teoreticheskaya i Matematicheskaya Fizika, Vol. 157, No. 3, pp. 391–405, December, 2008. 相似文献