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991.
Calcineurin (CaN) is a eukaryotic serine/threonine protein phosphatase activated by both Ca2+ and calmodulin (CaM), including intrinsically disordered region (IDR). The region undergoes folding into an α‐helix form in the presence Ca2+‐loaded CaM. To sample the ordered structure of the IDR by conventional all atom model (AAM) molecular dynamics (MD) simulation, the IDR and Ca2+‐loaded CaM must be simultaneously treated. However, it is time‐consuming task because the coupled folding and binding should include repeated binding and dissociation. Then, in this study, we propose novel multi‐scale divide‐and‐conquer MD (MSDC‐MD), which combines AAM‐MD and coarse‐grained model MD (CGM‐MD). To speed up the conformation sampling, MSDC‐MD simulation first treats the IDR by CGM to sample conformations from wide conformation space; then, multiple AAM‐MD in a limited area is initiated using the resultant CGM conformation, which is reconstructed by homology modeling method. To investigate performance, we sampled the ordered conformation of the IDR using MSDC‐MD; the root‐mean‐square distance (RMSD) with respect to the experimental structure was 2.23 Å. 相似文献
992.
高压密封消解技术在电厂盐垢分析中的应用 总被引:1,自引:0,他引:1
利用高压密封消解技术来消解蒸汽汽轮机叶片上的盐垢,确定了理想的消解体系及消解条件,能比较方便,快捷地完全消解盐垢,并对消解后的元素分析测定作了相应的研究,结果令人满意,本法的SiO2和Fe^3 的标准加入回收率分别为95%-101%和97%-108%。 相似文献
993.
994.
995.
Experimental study on scale inhibition performance of a green scale inhibitor polyaspartic acid 总被引:2,自引:0,他引:2
ZhenHua Quan YongChang Chen XiuRong Wang Cheng Shi YunJie Liu ChongFang Ma 《中国科学B辑(英文版)》2008,51(7):695-699
Static and dynamic experiments were carried out to validate scale inhibition performance of a green scale inhibitor-polyaspartic acid (PASP). From the static experiment, it was shown that below 60℃, polyaspartic acid is very effective in scale inhibition, with the scale inhibition ratio exceeding 90% with only 3 mg/L PASP for the 600 mg/L hardness solution. For a higher hardness solution of 800 mg/L, the scale inhibition ratio can also reach 90% with 6 and 12 mg/L PASP at 30 and 60℃respectively. The SEM photographs of CaCO3 crystals indicate that the crystal structure transforms from a compact stick-shape to a loose shape so that the scale can be washed away easily instead of being deposited on the heat transfer surface. The dynamic experimental results show that almost no scales formed on the heat trans- fer surface and the fouling thermal resistance decreases extraordinarily if PASP is added in the solution. 相似文献
996.
微锥阵列对碳纳米管薄膜强流脉冲发射的影响 总被引:1,自引:0,他引:1
采用酞菁铁高温热解方法,以化学镀铜层为缓冲层,在具有微锥结构阵列的硅基底上制备了CNTs薄膜,并采用二极结构,在20 GW脉冲功率源系统中对其强流脉冲发射特性进行了测试.结果表明:在相同的峰值电场下,CNT薄膜的发射电流峰值随基底微结构单元尺寸的减小而增大,且当脉冲电场的峰值增加时,CNT薄膜的发射电流的峰值增长速度随基底微结构单元尺寸的减小而增大.结合利用有限元分析软件ANSYS模拟计算的微锥阵列结构上表面的电场分布,研究了不同单元尺寸的微锥阵列对碳纳米管薄膜强流脉冲发射能力的影响. 相似文献
997.
Jiahao Yan Dayu Zhu Yanjun Bao Qin Chen Baojun Li Wenshan Cai 《Laser \u0026amp; Photonics Reviews》2024,18(4):2300592
To achieve optoelectronic devices with high resolution and efficiency, there is a pressing need for optical structural units that possess an ultrasmall footprint yet exhibit strong controllability in both the frequency and spatial domains. For dielectric nanoparticles, the overlap of electric and magnetic dipole moments can scatter light completely forward or backward, which is called Kerker theory. This effect can expand to any multipoles and any directions, re-named as generalized Kerker effect, and realize controllable light manipulation at full space and full spectrum using well-designed dielectric structures. However, the complex situations of multipole couplings make it difficult to achieve structural design. Here, generative artificial intelligence (AI) is utilized to facilitate multi-objective-oriented structural design, wherein the study leverages the concept of “combined spectra” that consider both spectra and direction ratios as labels. The proposed generative adversarial network (GAN) is named as DDGAN (double-discriminator GAN) that discriminates both images and spectral labels. Using trained networks, the simultaneous design for scattering color and directivities, RGB color routers, as well as narrowband light routers is achieved. Notably, all generated structures possess a footprint <600 × 600 nm indicating their potential applications in optoelectronic devices with ultrahigh resolution. 相似文献
998.
Effects of Reynolds number and angle of attack on the vortex shedding of a finite swept-back wing are experimentally studied. The cross-sectional profile of the wing is NACA 0012, and the sweep-back angle is 15° The time series signals detected by hot-wire in the wake region shows four distinct behaviors: laminar, subcritical, transitional, and supercritical. The derived Strouhal number curves are significantly different in these four behaviors. In addition, the statistical properties of turbulence, that is, the power spectrum density function, probability density function, correlation coefficient, Lagrangian integral time scales, and length scales are also presented in this paper. 相似文献
999.
The morphological stability of a growing faceted crystal is discussed. We argue that the interplay between nonuniformity in supersaturation on a growing facet and anisotropy of surface kinetics derived from the lateral motion of steps leads to a faceted instability. Qualitatively speaking, as long as the nonuniformity in supersaturation on the facet is not too large, it can be compensated for by a variation of step density along the facet, and the faceted crystal can grow in a stable manner. The problem can be modeled as a Hamilton-Jacobi equation for height of the crystal surface. The notion of a maximal stable region of a growing facet is introduced for microscopic time scale approximation of the original Hamilton-Jacobi equation. It is shown that the maximal stable region keeps its shape, determined by profile of the surface supersaturation, with constant growth rate by studying large time behavior of solution of macroscopic time scale approximation. A quantitative criterion for the facet stability is given. 相似文献
1000.
M. Salmhofer 《Annalen der Physik》2007,16(3):171-206
A class of continuous renormalization group flows with a dynamical adjustment of the propagator is introduced and studied theoretically for fermionic and bosonic quantum field theories. The adjustment allows to include self–energy effects nontrivially in the denominator of the propagator and to adapt the scale decomposition to a moving singularity, and hence to define flows of Fermi surfaces in a natural way. These flows require no counterterms, but the counterterms used in earlier treatments can be constructed using them. The influence of propagator adjustment on the strong–coupling behaviour of flows is examined for a simple example, and some conclusions about the strong coupling behaviour of renormalization group flows are drawn. 相似文献