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991.
Lifshitz Transitions Induced by Temperature and Surface Doping in Type‐II Weyl Semimetal Candidate Td‐WTe2
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992.
Xiaohuan MO 《Frontiers of Mathematics in China》2011,6(2):309-323
The purpose of this article is to derive an integral inequality of Ricci curvature with respect to Reeb field in a Finsler
space and give a new geometric characterization of Finsler metrics with constant flag curvature 1. 相似文献
993.
A class of boundary value problems for a third-order differential equation with a turning point is considered. Using the method of multiple scales and others, the uniformly valid asymptotic expansion of solution for the boundary value problem is constructed. 相似文献
994.
采用活性炭纤维作为电-Fenton反应的充氧阴极来降解水中活性艳红染料X3B,运用扫描电镜、紫外可见光谱、总有机碳分析等手段系统考察了电极形貌、底物吸附、铁离子初始价态、曝气等影响因素.实验结果表明,X3B在活性炭纤维表面的吸附符合Langmuir等温吸附模型,而X3B的电-Fenton降解反应则符合准一级反应动力学;通入空气能显著提高X3B的降解反应速率和矿化率,铁离子价态对此则无明显影响;X3B能被有效矿化,210min内矿化率为75.9%,表观电流效率达57.2%. 相似文献
995.
研究一个激光脉冲放大器增益通量的模型. 利用广义变分迭代方法, 首先决定Lagrange乘子,然后构造迭代关系式. 最后得到了相应模型近似解.
关键词:
非线性
变分迭代
激光脉冲放大器 相似文献
996.
997.
998.
Water located outside the NMR detection coil experiences a reduced RF field intensity. This "faraway water" is known to be very difficult to suppress and often gives rise to a large residual solvent signal. Pre-SAT180 (Pre-Saturation with Adiabatic Toggling of 180 degree pulse inversion) is proposed to cancel the residual water contribution efficiently. Compared with several popular methods such as 1D NOESY with pre-saturation or 270 degrees excitation, Pre-SAT180 has a number of advantages, including: full retention of signal intensity and selectivity, good phase properties, easy setup, and high tolerance to pulse missettings. 相似文献
999.
Rok Petkovšek Aleš Babnik Janez Diaci Janez Možina 《Applied Physics A: Materials Science & Processing》2008,93(1):141-145
We present a new method for monitoring of the laser micro-drilling process. The method is based on detection of acoustic waves
in air above the processed sample using a laser beam deflection probe (LBDP). We present an augmentation of the experimental
set-up by means of a digital micrographic system which enables the acquisition of images of the plasma plume and of the hole
cross-section during a drilling sequence. Comparing the acquired images with the detected LBDP signals, we examine the drilling
process from a new perspective. 相似文献
1000.
The aim of this study was to determine nHA/PMMA composites (H/P) in an optimal ratio with improved cytocompatibility as well as valid physical properties for provisional dental implant restoration. 20 wt.%, 30 wt.%, 40 wt.% and 50 wt.% H/P were developed and characterized using XPS, bending strength test and SEM. Human gingival fibroblasts cultured in extracts or directly on sample discs were investigated by fluorescent staining and MTT assay. Chemical integration in nHA/PMMA interface was indicated by XPS. Typical fusiform cells with adhesion spots were detected on H/P discs. MTT results also indicated higher cell viability in 30 wt.% and 40 wt.% H/P discs (P < 0.05). We conclude that nHA addition to PMMA enhances cytocompatibility and the optimal nHA/PMMA ratio for provisional fixed crowns (PFC) is 0.4:1. 相似文献