Effects of injection angle orientation on concave and convex surfaces film cooling

The present study employs a transient liquid crystal thermography to measure film cooling performance over constant curvature of concave and convex surfaces. This work investigates detailed distributions of both film cooling effectiveness and heat transfer coefficient on concave and convex surfaces with one row of injection holes inclined stream-wise at 35° at four blowing ratios (0.5, 1.0, 1.5 and 2.0) on four test pieces with different hole configurations. All test models have a row of discrete holes with a stream-wise injection angle (γ of 35° and a pitch-to-diameter ratio (P/d) of 3. The current work examines four different injection configurations, one with simple and three with 8° forward-expanded holes. Three compound angles of 0, 45 and 90° with air (ρ_c/ρ_m = 0.98) as coolants are tested under the mainstream Reynolds number (Re_d) of 2300 on concave surface, and 1700 on convex surface. Measured results of the concave surface show that both the span-wise averaged heat transfer coefficient and film cooling effectiveness increase with blowing ratios for all tested models. Higher heat transfer levels induced by large flow disturbance of compound-angle injection also lead to poorer overall film cooling performance, especially at high blowing ratio and large span-wise injection angle. Present results show that the best surface protection on the concave surface over the widest range of M can be provided by the forward-expanded holes with β = 0° (Model-B), followed by the forward-expanded holes with β = 45° (Model-C). Convex surface results show that the compound-angle injection indicates increases in both film cooling effectiveness and heat transfer at moderate and high blowing ratios. The forward-expanded hole with simple-angle injection provides the best film performance because of high film cooling effectiveness and low heat transfer coefficient at blowing ratio of 0.5.     

X射线衍射仪功能扩展的研究

通过软件实现了用 Ｐ Ｃ 机调用日本 Ｒｉｇａｋｕ 公司生产的 Ｄ／ ｍａｘ 一类 Ｘ 射线衍射仪测量数据，利用 Ｐ Ｃ 机的复杂计算功能，使原有仪器也可以进行新的结构分析工作，扩展了仪器的功能。     

电阻环法模拟测量电子束流的大小和位置

本文介绍了通过测量束流在输运管壁上形成的感应电流，来确定直线感应加速器束流大小、位置的一种方法。实验证明，这种测量方法不会影响电子束在管道中的传输，且测量精度高，装置简单，并可装在真空系统的外面，便于维修。     

Hydroformylation of methyl-3-pentenoate over a phosphite ligand modified Rh/SiO2 catalyst

A phosphite ligand modified Rh/SiO2 catalyst has been developed for hydroformylation of internal olefins to linear aldehydes, which showed high activity and regioselectivity and could be separated easily by filtration after reaction in an autoclave. Effects of reaction temperature and syngas pressure on the performances of the catalyst in the reaction were also investigated.     

波动方程反演问题的一种新的逼近方法

本文给出了一种求解波动方程反演问题的“多目标函数法”.这种方法简单、有效,并具有明确的物理意义.对于三维问题的程序化它有很强的优越性.     

Tetrahydrofolate coenzyme models: I. Synthesis of 1-methyl-2-phenyl-3-aryl imidazolinium iodide and benzylidyne (phenyl-substituted one carbon unit) transfer reactions

Four 1, 2, 3-trisubstituted imidazolinium iodides which were used as 5,10 -+CPh-THF model (7—10) at formic acid oxidation level were synthesized. The benzylidyne group (phenyl-substituted one carbon unit) transfer reactions from these compounds to Grignard reagent were investigated, and the reactions of these compounds with KBH₄ and NaOH were also studied.     

激光诱导固体表面化学过程的若干研究

本文采用氩激光倍频及准分子激光,对金属膜层的沉积、化合物膜层沉积、光诱导化学光刻以及激光化学诱导掺杂等固体表面化学过程作了实验研究,并对其中一些过程的机理作了探讨.     

UV irradiation induced formation of single-crystal gold nanonetworks with controllable pore distribution

Single-crystal gold nanonetworks and nanoplates with novel porous structures were synthesized through a continuous UV irradiation method. The structures of the porous nanonetworks and the nanoplates were found to be citric acid concentration dependent. Transmission electron microscopy (TEM) showed that the two-dimensional (2-D) nanonetworks prepared at the lower citric acid concentration (0.5 mM) had irregular pores and bigger area. Increasing the citric acid concentration resulted in formation of gold nanoplates with hexagonal, triangular or truncated triangular pores. When the acid concentration came to 2 mM, the nanoplates with single and double pores were observable. The selected area electron diffraction (SAED) patterns showed that both the nanonetworks and porous nanoplates were single-crystal. The presence of 1/3{4 2 2} reflections indicated that the surface of the gold nanonetwork and nanoplates is atomically flat.