Fe_3Al的抗高温氧化和耐热腐蚀性能

在７００℃与８５０℃的高温下，Ｆｅ＿３Ａｌ金属间化合物表面形成了Ａｌ＿２Ｏ＿３保护膜，使其抗氧化性能远优于不妨钢，２％Ｃｒ（原子百分比）加入Ｆｅ＿３Ａｌ会导致氧化过程初期氧化速率的增高，在熔融的硫酸盐和高压锅炉的烟气中，Ｆｅ＿３Ａｌ的耐热腐蚀性能优于高温合金ＧＨ１３２．     

基于KPI的企业绩效考核指标体系初探--以某物业管理公司建立绩效考核指标体系为例

在许多企业中，进行绩效管理常遇到一个实际性的问题就是很难确定客观的、量化的并与企业战略相对应的绩效指标体系。针对以上问题，以某物业管理公司为例，提出基于企业的战略目标、业务重点的关键绩效指标体系，将企业的战略目标转化为可量化的、可实施的内部目标。     

A Novel and Efficient Catalytic System for Aerobic Oxidative Coupling of 2-Naphthol Derivatives

The paper reported a novel and efficient aerobic oxidative coupling reaction of 2-naphthol derivatives catalyzed by CuCu (Ⅰ or Ⅱ)N-alkylimidazole complexes in excellent yields. The crystal structure of CuCu(Ⅱ)N-methylimidazole complex to be determined by X-Ray.     

Triterpenoid Constituents of Huperzia miyoshiana

Thirteen triterpenoids, including three new ones, miyoshianois A (1), B (2) and C (3), were isolated from Huperzia miyoshiana. The structures of these new compounds were established as 3-O-dihydroferuloyltohogenol (1), 16-oxo-3β,21β-dihydrox-y-serrat-14-en-24-ferulate (2) and 16-oxo-3a, 21β-dihydroxy-serrat-14-en-24-ferulate (3), respectively, on the basis of their spectroscopic analysis.     

Defect Structures in 4H-SiC Irradiated with Highly-energetic ^20Ne^4＋ and ^120Xe^26＋ Ions

The study of damage evolution in silicon carbide bombarded with energetic helium ions is important for the use of this material in future fusion reactors. Heavier inert gas atoms like Ne and Xe have similar behavior of diffusion and clustering with helium, and the comparison of damage accumulation behavior between energetic helium and heavier inert gas ions can reveal important aspects of underlying mechanisms. As an extension of our     

Time-Resolved Femtosecond Degenerate Four-Wave Mixing in LiNbO3：Fe,Mg Crystal

Forward degenerate four-wave mixing （DFWM） processes are investigated with a femtosecond pulsed laser in lithium niobate crystal doubly-doped with magnesium and iron （LiNbO3：Fe, Mg）. The pulse energy dependence reveals a pure third-order nonlinear response, and the third-order nonlinear susceptibility x^（3） in the material is evaluated to be 4.96 × 10^-13 esu. The time-resolved DFWM process shows a response time of x^（3） shorter than 100fs, which is due to the nonresonant electronic nonlinearities. Our results indicate that LiNbO3 crystals have potentials for ultrafast real-time optical processing systems, which require a large and fast x^（3） optical nonlinearity.     

反铁磁铜氧化合物中的磁致形状记忆

La2-xSrxCuO4(以下称LSCO)是最早发现的高温超导体之一.当x≈0.15时,它具有最高的超导转变温度,Tc=33K.对于x<0.02的轻度掺杂,材料的低温相是反铁磁绝缘体.在室温以上时,层状化合物LSCO晶格具有四方对称性;当冷却样品通过特征温度To,将发生从四方到正交的结构相变.此时,晶体发展出一种被称为孪晶的畴结构,被畴壁分开的相邻区域具有不同的晶轴取向.正交结构的晶格常数a=05339nm,b=0.5422nm,两者相差约1%.为了探求高温超导机理,LSCO曾被广泛深入地研究.由于在超导LSCO中根本不存在41meV反铁磁自…