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61.
以含铟的锌渣氧粉为原料,以硫酸为浸出剂,研究了锌渣氧粉在高压釜中浸铟时氧化剂种类和用量、酸初始浓度等工艺条件对铟浸出率的影响。结果表明,加压和氧化对铟的浸出过程都有较好的强化效果。在液固比为8、反应时间为150min、搅拌速度为575r/min、反应温度为90℃、空气压力为0.5MPa(表)和硫酸初浓度为500g/L的浸出条件下,在双氧水用量为0.5mL/(g矿)、高锰酸钾用量为0.025g/(g矿)时,铟浸出率可达到90%以上,比无氧化剂常压浸出提高了13个百分点。  相似文献   
62.
CH_4 storage associated with adsorbed natural gas(ANG) technology is an issue attracting great concern.Following the Advanced Research Project Agency-Energy(ARPA-E) targeted deliverable capacity of 315 cm~3·cm~(-3)(STP), hundreds of thousands of materials have been experimentally or theoretically evaluated,while the best results still show a 35% gap from the target. Moreover, recent theoretical research reveals that the target is beyond the possibility that real materials can be designed. To get rid of the awkward situation, we make attempts on investigating the CH_4 delivery performance under other operation conditions. Methods of raising the discharge temperature(to infinite high) or elevating the storage pressure(to 25 MPa) have been proved to show limited effectiveness. In this work, it is found that the ARPA-E target can be achieved by using a decreasing storage temperature strategy. By taking 280 Co RE(computation-ready, experimental) COFs(covalent organic frameworks) as ANG materials, when reduce the storage temperature to 190.6 K, the highest deliverable capacity can reach 392 cm~3·cm~(-3)(STP), and16.1% Co RE COFs can surpass the target. The target is also achievable when storage at 220 K. Structure performance relationships study shows strong correlation between deliverable capacity and void fraction. Hence, 120 hypothetical COFs are generated to ascertain the optimum void fraction. In addition,the performance of 2 D-COFs can be greatly enhanced by increasing the interlayer spacings, e.g. CH_4 deliverable capacity(storage at 190.6 K) of ATFG-COF can be improved from 239 to 411 cm~3·cm~(-3)(STP) when interlayer spacing is enlarged to 1.65 nm.  相似文献   
63.
以福建省4个果梅主栽品种青竹梅、龙眼梅、杭梅和白粉梅为试材,分析测定果实的主要性状和营养成分,包括单果质量、果实大小、VC、总酚、类黄酮、可溶性糖、有机酸、香气组分以及矿质元素含量.结果表明,4个果梅品种VC、总酚、类黄酮、可溶性糖、有机酸、香气组分以及矿质元素含量存在显著差异.果梅主要可溶性糖为蔗糖,其次为葡萄糖和果...  相似文献   
64.
65.
对建立的Consteel配合竖炉电弧炉预热炉料的炼钢工艺过程静态控制数学模型的运算结果进行了分析讨论。该模型用于Consteel电弧炉的改造设计以及Consteel竖炉实际预热过程静态控制。  相似文献   
66.
The additives-doped α-nickel hydroxides were prepared by supersonic co-precipitation method. The crystal structure and grain size of the prepared samples were characterized by X-ray diffraction (XRD) and Particle size distribution (PSD), respectively. Cyclic voltammetry (CV) tests show that Al-Co-Y doped Ni(OH)2 has better reaction reversibility, higher proton diffusion coefficient than those of Al-Co doped Ni(OH)2. Al-Co-Y doped Ni(OH)2 also has lower charge-transfer resistance as shown by electrochemical impedance spectroscopy (EIS). Charge/discharge tests show that the discharge capacity of Al-Co-Y doped Ni(OH)2 reaches 328 mAh/g at 0.2 C and 306 mAh/g at 0.5 C, while Al-Co doped Ni(OH)2 can only discharge a capacity of 308 mAh/g at 0.2 C and 267 mAh/g at 0.5 C.  相似文献   
67.
以鸡蛋清为材料,探讨了加热处理方式和加热时间对鸡蛋清凝胶硬度、回复性以及持水性的影响.结果表明:蛋清微波加热凝胶形成速度比传统水浴加热快.蛋清在75℃水浴加热20 min开始形成凝胶,凝胶硬度为21.83 g,90℃加热50 min达到最大值779.50 g;微波100 W加热25 s即可形成凝胶,凝胶硬度为46.90 g;20 W加热160 s达到最大值266.23 g.与水浴加热相比,微波加热蛋清凝胶的持水性最低值为84.10%,回复性均在60%以上,回复性得到明显改善.  相似文献   
68.
Alpha nickel hydroxide has better performances than commercial beta nickel hydroxide. However, the main defect is that α-phase is difficult to synthesize and easily transformed to β-phase Ni(OH)_2 upon aging in a strong alkaline solution. In this study, the Al-Co, Al-Yb, Yb-Co and Al-Yb-Co multiple doping was used respectively. By controlling the amount of sodium carbonate, the α-Ni(OH)_2 was prepared by ultrasonic-assisted precipitation. And the influence of sodium carbonate on the crystalline phase and structure stability for alpha nickel hydroxide was studied. The results demonstrate that, with increasing amount, the biphase nickel hydroxide transforms to pure alpha nickel hydroxide gradually, and the structure stability is also improved. When the amount of sodium carbonate is 2 g, the sample still keeps α-Ni(OH)_2 after being aged for 30 days, for Al-Yb-Co-Ni(OH)_2. And when the amount is less than 2 g, the phase transformations exist in the samples with different extents. These results demonstrated that the amount of sodium carbonate is a critical factor to maintain the structural stability of α-Ni(OH)_2.  相似文献   
69.
Ternary heterojunctions g-C3N4/ZnS/CuS with different morphologies were constructed. The g-C3N4/ZnS/CuS (hexagonal-nanosheets) exhibited the largest photocurrent, the best photocatalytic and electrochemical activity, which revealed the influence discipline of different morphologies on photoconductivity, photo/electro-catalytic activity. It indicated that this heterojunction can be used as an excellent photoconductor device, a high-efficiency photo/electro-catalyst.

Graphical Abstract

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70.
田芳  司敏杰  李红霞  沈洁  张艳娟 《玻璃》2018,45(6):29-33
从热膨胀的本质和热膨胀仪的测试曲线出发,分析了热膨胀曲线对玻璃理化性能和结构的表征,简要介绍了热膨胀仪测试玻璃热收缩率的方法。热膨胀仪的应用对玻璃理化性能的表征、玻璃微观结构的研究以及对玻璃的生产调控都有一定的理论和实验指导作用。  相似文献   
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