Preparation and electrochemical performance of nanosized Co3O4 via hydrothermal method

The hydrotalcite-type cobalt compounds were prepared through oxidation of Co（OH）2 gel using NH4OH as precipitating agent and H2O2 as oxidant. These hydrotalcite-type cobalt compounds were transformed into Co3O4 through hydrothermal decomposition with nanostructural deformation. The precursor and product were characterized by Fourier-transform infrared（FT-IR） spectrum, X-ray diffractometry（XRD） and transmission electron microscopy（TEM）. The electrochemical performances of as-prepared nanosized Co3O4 as anode materials in lithium-ion batteries were tested by charge-discharge test in the voltage range of 0-3.0 V. The influence of morphology of Co3O4 particle on the capacity and cycling performance was studied. The results show that the shape and size of the final product can be controlled by altering cobalt sources. The irregular cubic Co3O4 with the average particle size of about 10 nm shows the best electrochemical performance. After 10 charge-discharge cycles, the specific charge capacity retains 555 mA.h/g.     

新型纳米晶合金Fe69.5Cu0.5Cr4V5Si13B8退火过程中微结构的M…

采用Ｍｏｓｓｂａｕｅｒ、Ｘ射线衍射和透射电镜等实验方法，较为系统地研究了非晶态ＦｅＣｕＣｒＶＳｉＢ合金及期经过不同温度退火后的晶化特性和微观组织的变化，介绍了实验方法并对研究结果进行了分析探讨。     

Performances of electrically heated microgroove vaporizers

An electrically heated microgroove vaporizer was proposed. The vaporizer mainly comprised an outer tube, an inner tube and an electrical heater cartridge. Microgrooves were fabricated on the external surface of the inner tube by micro-cutting method, which formed the flow passage for fluid between the external surface of the inner tube and the internal surface of the outer tube. Experiments related to the temperature rise response of water and the thermal conversion efficiency of vaporizer were done to estimate the influences of microgroove＇s direction, feed flow rate and input voltage on the performances of the vaporizer. The results indicate that the microgroove＇s direction dominates the vaporizer performance at a lower input voltage. The longitudinal microgroove vaporizer exhibits the best performances for the temperature rise response of water and thermal conversion efficiency of vaporizer. For a moderate input voltage, the microgroove＇s direction and the feed flow rate of water together govern the vaporizer performances. The input voltage becomes the key influencing factor when the vaporizer works at a high input voltage, resulting in the similar performances of longitudinal, oblique and latitudinal microgroove vaporizers.     

苏联钛熔铸生产的现状和特点

苏联海绵钛的产量居世界首位,钛锭和钛铸件的生产能力很大,熔铸技术比较先进,有一套独特的熔铸工艺和设备,引起了各国钛冶金工作者的注意。在过去三十年期间,苏联钛的熔铸生产有以下几个特点。     

第五章 热体积模锻

1.坯料准备和模锻温度规范热体积模锻是在大批量生产条件下,由钛及其合金制取复杂形状零件最普遍的方法之一。在钛及其合金的热模锻时,经常出现压折、皱折、斑疤等类型的废品。这种废品是在单位变形抗力较小、金属内层塑性较大情况下,坯料尖锐角快速冷却的后果。所以,对于钛合金的模锻,推荐采用圆角坯     

梁赞有色冶金工厂采用钛装置

在梁赞有色冶金工厂的主要工序中采用了含硫酸盐和金属氟化物杂质的硫酸腐蚀溶液,气体含硫化物,氟化物和二氧化碳,氟,氯以及硫酸蒸气。由于材料快速腐蚀破坏,所用装置的工作寿命不长。在某些工序中应用钛制装置可以延长其使用寿命,降低生产消耗,强化工艺过程。在湿法冶金,微尘回收和配料干燥车间所进行的、BT1—0、BT5—1钛合金与X18H10T、X17H13M2T钢的对比腐蚀试验(见表)表明:在大多数研究介质中     

海绵钛质量与残钛利用率及钛冶金半成品质量的关系

在熔铸生产中,任何合金铸锭及铸件的质量均与原始炉料的质量直接相关。海绵钛约占成批生产钛合金炉料组份比例的60%以上,海绵钛质量的高低对钛合金     

钢纤维切割机技术数据

外形尺寸 :30 0 0 mm× 85 0 mm× 12 5 0 mm铣刀轴转速 :2 0 0 r/ min～ 6 30 r/ min铣刀直径 :2 0 0± 5 mm钢带送进速率 :2 0 0 mm/ min～ 5 6 0 0 mm/ min钢带厚度 :0 .4 mm～ 0 .8mm* *钢带宽度 :2 4 0 mm～ 30 0 mm钢带卷质量 :达 1.2 5 t钢带卷最大外径 :≤ 5 0 0 mm铣刀传动装置功率 :7.5 k W钢带送进装置功率 :0 .75 k W交流电网电压 :380 V/ 2 2 0 V电流频率 :5 0 Hz生产效率 :118kg/ h*设备利用率 :0 .8～ 0 .9设备重量 :980 kg*设备生产效率是指下列工作参数时的指标 :钢带宽度 30 0 mm,钢带厚度 0 .5 mm,送进速度 0 .5 mm/齿…     

粉未冶金与技术进步

粉末冶金是以最新物理、物理化学和工艺成就为基础的新兴技术领域,正在根本改变传统的冶金和机器制造方法,为传统冶金工艺所不能制取的可调孔隙度金属、熔浸双     

多辊孔型轧机轧制钼棒

变形抗力高、塑性差、高温下剧烈氧化和吸气及其他一些特性使钼及其合金难于进行压力加工,并对设备及工艺条件有特殊要求。旋锻、自由锻、挤压及轧制生产棒材,用粉末冶金烧结条及铸锭作坯料。现在生产钼棒的方法效率低、金属损耗大,并且不可能得到高精度及优质表面的棒材。为消除上述缺点,切利亚宾斯克工学院轧制教研室用多辊孔型轧机轧制了钼及其合金棒材。