等离子喷涂铁基非晶/晶体复合涂层的工艺–结构–性能关系

本研究试图通过优化等离子喷涂参数来开发一种Fe基非晶/晶体涂层,该涂层主要成分来自一种贫乏的铁基合金（Fe_92.6C_3.5P_1.4Si₂Mn_0.5）。这种合金是钢铁厂高炉产出的生铁剩余废料。为了经济有效地重新利用这种残留物,这种合金在合成时对成分进行了最少的修改。同时,本研究还探讨了涂层的结构、机械、腐蚀和磨损性能对喷涂参数（等离子功率、主气体流速、送粉速度和间隔距离）的依赖性。X射线衍射表明,在最优的喷涂参数下沉积的涂层存在无定形/晶体相。在较低等离子功率和最高气体流速下沉积的涂层表现出更好的密度、硬度和耐磨性。所有涂层都表现出良好的耐腐蚀性（腐蚀环境:3.5wt% NaCl 溶液）。机械、磨损和摩擦学研究表明,单一的工艺参数优化无法提供良好的涂层性能;相反,所有工艺参数在优化涂层性能都具有独一无二的作用,它们主要通过控制飞行中的颗粒温度和速度分布,以及熔滴撞击基材之前的冷却模式来控制涂层性能。     

Influence of oestradiol on tissue respiration of the Indian garden lizard,Calotes versicolor

Summary Ovariectomy reduced the respiratory rates of liver and skeletal muscle homogenates of the Indian garden lizard,Calotes versicolor. Administration of oestradiol dipropionate elevated the rate of tissue respiration of ovariectomized animals. This finding lends support to the view that oestradiol, like testosterone, is able to stimulate the oxidative metabolism of this animal.Part of a thesis qualified for the award of Ph.D. degree of Banaras Hindu University, Varanasi, India. The author expresses his deep sense of gratitude to Professor J. P. Thapliyal of the Department of Zoology, Banaras Hindu University for valuable guidance and constant inspiration. Financial assistance was provided by a Council of Scientific and Industrial Research (New Delhi) Junior Research Fellowship.     

Hepatic silver binding protein (Ag BP) from sparrow (Passer domesticus)

A silver binding protein (Ag BP) has been identified in the liver of sparrows administered a tracer dose of 110mAg. The protein as purified by gel-filtration shows a major absorption maximum at 260 nm and a minor one at 225 nm. It has a mol.wt of 9500 daltons and is stable when exposed to high temperature (64 degrees C for 15 min) as well as to acidic pH (2.2).     

A wide depth distribution of seismic tremors along the northern Cascadia margin

The Cascadia subduction zone is thought to be capable of generating major earthquakes with moment magnitude as large as M(w) = 9 at an interval of several hundred years. The seismogenic portion of the plate interface is mostly offshore and is currently locked, as inferred from geodetic data. However, episodic surface displacements-in the direction opposite to the long-term deformation motions caused by relative plate convergence across a locked interface-are observed about every 14 months with an unusual tremor-like seismic signature. Here we show that these tremors are distributed over a depth range exceeding 40 km within a limited horizontal band. Many occurred within or close to the strong seismic reflectors above the plate interface where local earthquakes are absent, suggesting that the seismogenic process for tremors is fluid-related. The observed depth range implies that tremors could be associated with the variation of stress field induced by a transient slip along the deeper portion of the Cascadia interface or, alternatively, that episodic slip is more diffuse than originally suggested.     

Toxicity of Temik (aldicarb) for a fresh water teleost,Barbus conchonius Hamilton

Summary The toxic effects of Temik (aldicarb) on a fresh water Himalyan lake teleost,Barbus conchonius were investigated in hard and soft water. The 48-, 72- and 96-h TL_m-values in mg/l were 8.99, 2.39 and 2.42 respectively in the hard-water test and 3.30, 0.62 and 0.46 in the soft-water test. The toxicity of Temik toB. conchonius increases many fold in soft water.One of us (S. C. P.) is grateful to U. G. C., for the award of a senior research fellowship.