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91.
Purification and Characterization of Cyclic AMP-Binding Protein from Ganoderma lucidum 总被引:1,自引:0,他引:1
WANGQi KIMJung-Sik CHUNGKi-Chul 《高等学校化学研究》2004,20(5):588-593
Cyclic AMP-binding protein was purified 30 fold from the mycelia of Ganoderma lucidum by the methods of ammonium sulfate precipitation, DEAE-cellulose, phospho-cellulose ion exchange chromatography and Sephacryl S-100 gel filtration. The molecular mass of the purified protein is 34.5 kDa and 17 kDa by Sephacryl S-100 gel filtration and SDS-ployacrylamide gel electrophoresis, respectively. From these results it is suggested that the protein has a homometric dimmer structure. The pI of the purified protein is pH 8.2 by native isoelectric focusing gel. The half-life of the protein activity in 10% glycerol at 4 ℃ is 7 d in crude extract, but its half-life is only 3 d under purifying conditions. The optimal conditions of the protein activity are at 1 ℃ and pH 7.5. Its activity is increased 6 times by 1 mmol/L Zn^2 and is slightly inhibited by cGMP,Cu^2 and Mn^2 . 相似文献
92.
Non-Invasive Measurements of Thickness of Superconductor Films by Using Two-Resonant-Mode Rutile Resonator 下载免费PDF全文
JUNG Ho Sang YANG Woo Il LEE Jae Hun SOHN Jae Min CHOO Kee Nam KIM Bong Goo LEE Sang Young 《中国物理快报》2010,27(8):203-206
The film thickness should be known for extrazting the intrinsic surface resistance from the effective surface resistance as measured by using the dielectric resonator method. Thicknesses of 70 nm to 360 nm are measured for YBa2 Cu3 O7-δ films in a non-invasive way by using the two-resonant-mode dielectric resonator (TDR) method. A futile resonator with the respective resonant frequencies of 15.25-15.61 GHz and 15.10-15.37 GHz for the TE021 and the TE012 modes is used for this purpose. Differences between the values as measured by using the TDR technique and those measured by using a step profilometer appear to be less than 3%, which is smaller than the previous value of 5% as measured by using a 8. 6 GHz single-resonance mode futile resonator [Lee et al. J. Korean Phys. Soc. 54(2009)1619]. Merits of using the TDR method are discussed. 相似文献
93.
Controllable Ultra Low- k by Via-Typed Air Gap with the Better Design Margin for Logic Devices below 45nm Node 下载免费PDF全文
By changing the air gap to a via-typed air gap, the height of the air gap is reduced up to about 50% compared to the height of the trench-typed air gap. The controllable (1 ≤h 〈 2.9) ultra low-k is also easily fabricated by adjusting the space of the via-typed air gap. The via-typed air gap makes the design margin better due to its lower height in the dense and narrow lines. 相似文献
94.
The authors mainly concern the set U f of c ?? ? such that the power deformation $ z(\frac{{f(z)}} {z})^c $ is univalent in the unit disk |z| < 1 for a given analytic univalent function f(z) = z + a 2 z 2 + ?? in the unit disk. It is shown that U f is a compact, polynomially convex subset of the complex plane ? unless f is the identity function. In particular, the interior of U f is simply connected. This fact enables us to apply various versions of the ??-lemma for the holomorphic family $ z(\frac{{f(z)}} {z})^c $ of injections parametrized over the interior of U f . The necessary or sufficient conditions for U f to contain 0 or 1 as an interior point are also given. 相似文献
95.
Production cross-sections of the therapeutic 105Rh radionuclide from proton-induced reactions on natural palladium target were measured using stacked-foil activation technique combined with high resolution ??-ray spectrometry at the MC50 cyclotron of the Korea Institute of Radiological and Medical Sciences. Note that cyclotron production of the 105Rh radionuclide from natural palladium target was measured here for the first time. Results are compared with the theoretical values obtained using the model codes TALYS and ALICE-IPPE. Thick target integral yields for the investigated 105Rh radionuclide were deduced from the threshold energy to 40?MeV. Measured data of the 105Rh radionuclide are important because of its potential applications in nuclear medicine and/or therapeutic purposes. Optimal production circumstances for the therapeutic 105Rh radionuclide using a cyclotron are discussed elaborately. 相似文献
96.
MINHYONG KIM 《Compositio Mathematica》1997,105(1):43-54
We extend a result of Vojta on height inequalities for algebraic points oncurves over function fields to include the case of positivecharacteristic. The main tool used is the Kodaira--Spencer map anddestabilizing flags for vector bundles on curves. 相似文献
97.
Y.-H. KIMS.-M. KIM 《Journal of sound and vibration》2002,254(2):231-244
There have been many attempts to understand the coupling phenomena between a solid structure and the surrounding fluid. However, the studies were restricted to interaction only between a structure and a finite cavity or a structure and acoustic field of infinite size. The system that we have studied has a structure that faces both a cavity of finite size and an external field of semi-infinite size. We also allow a hole, which can directly interact with the cavity as well as the external field. This configuration, therefore, provides two different interactions, or communication means. One is the finite structure and the other is the hole of finite size. This paper studies as to how these two components interact with the other two systems: the finite cavity covered by the structure and the hole, and the semi-infinite fluid. For simplicity, a two-dimensional and partially opened cavity coupled with a membrane and an exterior field was selected. The solution has to be found by solving a boundary value problem, but this case has to do with the boundaries that have two different conditions: one is the membrane and the other is the hole. The solution has been found in terms of the modal functions that satisfy the boundary conditions of finite cavity, membrane and hole. Non-dimensional coupling coefficients are obtained from the solution. The results exhibit that the coupling effect gives additional peaks and troughs in the averaged pressure of the cavity. These peaks and troughs are symmetrically arranged with respect to Helmholtz frequency of the cavity. The strong coupling occurs at the trough frequencies where the membrane interacts actively with the cavity and the exterior field. 相似文献
98.
The modified switching conditions of directional coupler optical switches, in the presence of parasitic couplings in bending sections, are discussed by means of the coupled mode theory. As expected, a parallel section's length needs to be adjusted by less than the coupling length lc (=pi/2kappa0), depending on the amount of parasitic coupling. For weak parasitic coupling, however, the switching voltage does not need to be altered but maintains the same value as without parasitic coupling. 相似文献
99.
Xianghua Guo Daining Fang Ai Kah Soh Hyun Chul KIM Jung Ju Lee 《Acta Mechanica Sinica》2006,22(1):34-39
This paper presents an efficient meshless method for analyzing cracked piezoelectric structures subjected to mechanical and
electrical loading. In this method, an element free Galerkin (EFG) formulation, an enriched basic function and some special
shape functions that contain discontinuous derivatives are employed. Based on the moving least squares (MLS) interpolation
approach, the EFG method is one of the promising methods for dealing with problems involving progressive crack growth. Since
the method is meshless and no element connectivity data are needed, the burdensome remeshing procedure required in the conventional
finite element method (FEM) is avoided. The numerical results show that the proposed method can yield an accurate near-tip
stress field in an infinite piezoelectric plate containing an interior hole. In another example studying a ceramic multilayer
actuator, the proposed model was found to be accurate in the simulation of stress and electric field concentrations arround
the abrupt end of an internal electrode.
The project supported by the National Natural Science Foundation of China (10025209, 10132010, and 90208002), and the Research
Grants Council of the Hong Kong Special Administrative Region, China (HKU 7203/03E). The English text was polished by Yunming
Chen. 相似文献
100.
Mizuno和Sato定义了有向图的Zeta函数(见Linear Algebra Appl.,2001,336:181-190),它可用来计算有向图中具有给定长度的所有圈的个数.给出了任意有向图的覆盖的Zeta函数的计算公式.作为推论,覆叠重数为2,3和4的任意有向图覆盖(正则或非正则)的Zeta函数被计算出来,同时也计算了Cayley有向图的Zeta函数. 相似文献