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91.
以国外某高磷鲕状赤铁矿为研究对象进行脱磷研究,该高磷矿铁品位为55.81%,磷含量为0.72%,铁矿物主要为磁铁矿和赤铁矿,48.61%的磷存在于磷酸盐中,47.22%的磷分布于铁矿物中。研究了脱磷剂用量、秸秆炭用量、还原温度以及还原时间对粉末还原铁指标的影响。结果表明:无脱磷剂碳酸钙时,无法获得合格的指标;在碳酸钙用量为25%,秸秆炭用量为12.5%,还原温度1 200 ℃,还原时间为75 min,还原产品两段磨矿两段磁选的条件下,可获得铁品位、铁回收率以及磷含量分别为94.27%、87.34%以及0.077%的粉末还原铁,该产品可作为电炉炼钢的优质原料。不加添加剂时,部分含磷矿物被还原成单质磷进入到金属铁中,故粉末还原铁磷含量较高,当碳酸钙用量为25%时,含磷矿物的还原受到抑制而保留在脉石相中,可实现降磷目的,而还原时间过长时,磷仍在脉石相中,铁颗粒将部分含磷矿物包裹,磨矿难以分离,导致磷含量升高。 相似文献
92.
Hydrogels for absorbing metal ions in wastewater have attracted more attentions in the environmental field especially for recent years. The removal efficiency of hydrogel adsorbents for eliminating metal ions is highly related with the effective contact between adsorbents and adsorbates. However, poor water absorption capacity of the hydrogel adsorbents would restrict on the expose of adsorption sites to the targeted subjects, causing undesirable removal ratio (RR) especially for metal ions at trace level. Thereby, the reported hydrogel adsorbents mainly focus on the removal of high content but not the trace level of metal ions so far. In this work, poly(acrylamide) (PAM)/poly(acrylic acid) (PAA)/Ca(OH)2 composite hydrogel is applied to adsorb trace metal ions. Swelling ratio of such PAM/PAA/Ca(OH)2 gel reaches 2,530 g/g, resulting in effective exposure of active sites and further expected RR for trace metal ions. The RRs of such adsorbent for Cu2+ (initial concentration C0 = 0.064 mg/L), Al3+ (C0 = 0.27 mg/L), Co2+ (C0 = 0.59 mg/L), Cr6+ (C0 = 0.52 mg/L), Mn2+ (C0 = 0.55 mg/L), Ni2+ (C0 = 0.59 mg/L), Zn2+ (C0 = 0.65 mg/L), Ag+ (C0 = 1.08 mg/L), and La3+ (C0 = 1.39 mg/L) are 56.6, 80.8, 41.3, 29.3, 34.6, 44.6, 55.9, 45.8, and 35.5%, respectively. This work broadens the application of hydrogel adsorbent for eliminating trace metal ions from polluted water. 相似文献
93.
Spherical LiNi1/3Co1/3Mn1/3O2 cathode particles were resynthesized by a carbonate co-precipitation method using spent lithium-ion batteries (LIBs) as a raw material. The physical characteristics of the Ni1/3Co1/3Mn1/3CO3 precursor, the (Ni1/3Co1/3Mn1/3)3O4 intermediate, and the regenerated LiNi1/3Co1/3Mn1/3O2 cathode material were investigated by laser particle-size analysis, scanning electron microscopy–energy-dispersive spectroscopy (SEM-EDS), thermogravimetry–differential scanning calorimetry (TG-DSC), X-ray diffraction (XRD), inductively coupled plasma–atomic emission spectroscopy (ICP-AES), and X-ray photoelectron spectroscopy (XPS). The electrochemical performance of the regenerated LiNi1/3Co1/3Mn1/3O2 was studied by continuous charge–discharge cycling and cyclic voltammetry. The results indicate that the regenerated Ni1/3Co1/3Mn1/3CO3 precursor comprises uniform spherical particles with a narrow particle-size distribution. The regenerated LiNi1/3Co1/3Mn1/3O2 comprises spherical particles similar to those of the Ni1/3Co1/3Mn1/3CO3 precursor, but with a narrower particle-size distribution. Moreover, it has a well-ordered layered structure and a low degree of cation mixing. The regenerated LiNi1/3Co1/3Mn1/3O2 shows an initial discharge capacity of 163.5 mA h g?1 at 0.1 C, between 2.7 and 4.3 V; the discharge capacity at 1 C is 135.1 mA h g?1, and the capacity retention ratio is 94.1% after 50 cycles. Even at the high rate of 5 C, LiNi1/3Co1/3Mn1/3O2 delivers the high capacity of 112.6 mA h g?1. These results demonstrate that the electrochemical performance of the regenerated LiNi1/3Co1/3Mn1/3O2 is comparable to that of a cathode synthesized from fresh materials by carbonate co-precipitation. 相似文献
94.
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96.
孙研 《电信工程技术与标准化》2006,19(6):1-1
通信电源是保障整个通信网络正常运行的关键基础设施,安全和节能是通信电源专业永恒的主题,根据年度工作计划安排,中国移动通信集团公司网络部在2006年初开展了通信电源专辑论文征集活动,该活动共收到26个省上报的155篇论文,经集团公司、北京、广东、浙江、江苏、江西省公司和京移通信设计院编辑部组成的评审委员会专家们的认真评选,共评选出一等奖7篇,二等奖8篇,三等奖12篇. 相似文献
97.
Fenton氧化法去除酱油生产废水中焦糖色素的研究 总被引:1,自引:0,他引:1
着重考察了Fenton试剂对水中焦糖色素降解的影响因素.从试验中得出,这些影响因素包括pH、催化剂的投加方式、催化剂与氧化剂的化学计量数以及反应时间等.Fenton反应中,pH4的条件下处理效果最好,反应进行40min时去除率达到90%. 相似文献
98.
P. L. Sun E. K. Cerreta G. T. Gray III J. F. Bingert 《Metallurgical and Materials Transactions A》2006,37(10):2983-2994
Commercial purity aluminum AA1050 was subjected to equal channel angular extrusion (ECAE) that resulted in an ultrafine-grained
(UFG) microstructure with an as-received grain size of 0.35 μm. This UFG material was then annealed to obtain microstructures
with grain sizes ranging from 0.47 to 20 μm. Specimens were compressed at quasi-static, intermediate, and dynamic strain rates
at temperatures of 77 and 298 K. The mechanical properties were found to vary significantly with grain size, strain rate,
and temperature. Yield stress was found to increase with decreasing grain size, decreasing temperature, and increasing strain
rate. The work hardening rate was seen to increase with increasing grain size, decreasing temperature, and increasing strain
rate. The influence of strain rate and temperature is most significant in the smallest grain size specimens. The rate of work
hardening is also influenced by strain rate, temperature, and grain size with negative rates of work hardening observed at
298 K and quasi-static strain rates in the smallest grain sizes and increasing rates of work hardening with increasing loading
rate and grain size. Work hardening behavior is correlated with the substructural evolution of these specimens. 相似文献
99.
100.