木薯渣—硫酸法浸出低品位软锰矿试验研究

研究了用木薯渣─硫酸法浸出低品位软锰矿,即以木薯渣作还原剂,在硫酸溶液中浸出低品位软锰矿。通过正交试验,考察了硫酸初始质量浓度、温度、固液质量体积比和反应时间对锰浸出效果的影响。结果表明,对锰浸出率影响较大的依次为温度、硫酸初始质量浓度、反应时间和固液质量体积比。单因素试验结果表明:锰浸出率随温度升高、硫酸初始质量浓度增大、反应时间延长和木薯渣添加量增加而提高;在温度90℃、硫酸初始质量浓度200g/L、反应时间4h、固液质量体积比1∶15、木薯渣与软锰矿质量比1∶6.79条件下,锰浸出率达97.32%。     

电炉渣在NH4Cl溶液浸出过程的自阻模型

针对电炉渣在NH4Cl溶液中的浸出过程,重点研究了电炉渣粒径、浸出温度、浸出时间和NH4Cl浓度对Ca2＋浸出率的影响规律,并建立了带有自阻系数的反应过程动力学模型.结果表明,电炉渣中钙离子的转化率随着浸出温度和氯化铵浓度的增大而增大,浸出反应过程的自阻系数为1.0307-1.0617,反应过程的活化能约为15.046 kJ/mol,表明该实验条件下电炉渣在氯化铵溶液中的浸出反应过程控速机制为扩散控速.     

转炉钢渣钙基活性组分乙酸浸出研究

以转炉钢渣为浸出对象,乙酸作为浸出剂,在热力学研究的基础上考察了不同粒度下浸出温度、时间、乙酸浓度和固液比对转炉钢渣中钙离子浸出率的影响规律。研究结果表明,在273.15~373.15 K的温度区间内,钢渣中Ca O、Ca_2SiO_4物相的钙离子浸出反应的吉布斯自由能ΔG0,而CaTiO_3物相的钙离子浸出反应的吉布斯自由能ΔG0。转炉钢渣中钙基活性组元的浸出迅速,粒度越细、固液比越小,钙基活性组元的浸出率越高;乙酸浓度越高,钙的浸出率越大。在乙酸浓度为1 mol/L、固液比为1∶20、浸出时间为60 min、浸出温度为70℃条件下,钙的浸出率高达87.52%。XRD和SEM分析表明,转炉钢渣中活性氧化钙全部浸出,转炉钢渣表面形成不规则孔隙,而钛酸钙(CaTiO_3)则留在渣相中。     

含铅锌渣中铅的富集

提出低酸—高酸两段逆流浸出含铅锌渣新工艺,低酸浸出考察液固比、时间和温度对锌浸出率的影响,高酸浸出考察初始硫酸浓度、时间和温度对锌浸出率及铅品位的影响。结果表明,在低酸浸出,液固比6∶1、时间5h、温度60℃;高酸浸出,初始硫酸浓度170g/L、时间6h、温度95℃的最优条件下,锌浸出率99.29%,铅入渣率98.58%,高浸渣中铅品位62.25%。     

用氢氧化钠从银渣中浸出硒碲试验研究

银渣主要含银、硒及少量铁、铜、铋、锑、碲、铅等,硒以亚硒酸银形式存在。研究了用氢氧化钠从银渣中选择性浸出硒、碲,考察了浸出时间、反应温度、液固体积质量比、氢氧化钠浓度对硒、碲浸出率的影响。试验结果表明:氢氧化钠浓度和液固体积质量比对硒、碲浸出率影响较大,硒和部分碲被浸出,其他元素如银、铜、铁等及部分碲留在渣中,浸出过程具有选择性;在反应温度95℃、液固体积质量比4∶1、氢氧化钠初始质量浓度200g/L、搅拌速度250r/min条件下浸出4h,硒、碲浸出率分别为97.22%和36.75%。此外,也研究了用硝酸浸出碱浸渣中的银。浸出渣衍射分析结果表明,渣中残留的硒主要以亚硒酸钠形式存在,需要用氢氧化钠再次浸出。     

SO2-H2SO4体系中锌浸渣还原浸出锌和铟

以锌浸出渣为对象,研究了在硫酸—二氧化硫体系还原浸出锌浸渣过程中反应温度、转速、液固比、初始硫酸浓度、SO2分压对锌和铟浸出行为及浸出率的影响。结果表明:采用SO2对锌浸渣进行还原浸出能够大幅提高锌和铟的浸出率,在SO2-H2SO4体系下锌浸渣还原过程中的锌和铟的浸出行为及动力学特性符合二级反应方程,浸出过程受到化学反应控制,表观活化能分别为21.72和39.16kJ/mol,提高温度能够显著提高锌和铟的浸出速率,提高液固比和初始硫酸浓度对锌和铟浸出速率影响较小,在一定范围内提高二氧化硫分压对锌和铟浸出速率影响较为显著。在反应温度105℃、转速500r/min、液固比8、初始硫酸浓度120g/L、SO2分压200kPa的条件下反应150min,锌浸出率达到96%以上、铟浸出率达到95%以上。     

锌冶炼铅银渣湿法浸出工艺研究

在分析湿法炼锌铅银渣的主要成分与化学物相的基础上,考察了温度、浸出时间、氯酸钠浓度、酸度等对铅银渣中铅银含量及浸出率的影响,确定了氯化浸出最优工艺条件为:氯化钠浓度300g/L、氯化钙浓度50g/L、初始盐酸0.4mol/L、浸出温度85℃、浸出时间2.5h、液固比8,在该条件下铅银渣中铅、银的浸出率分别可达94.43%和91.48%,渣中铅含量为0.9%,银含量84.4g/t。     

在酸性氯化物水溶液中同时浸出海洋锰结核与镍锍

用盐酸氯化物溶液同时浸出太平洋底锰结核和镍锍。在1.5～2.0molHCl溶液中95℃下浸出80分钟,可得到约100%的Mn,80%的Co,高于90%的Ni和Cu浸出率。实验考查了温度,酸度和初始铜离子浓度对浸出过程的影响。用电子显微镜检验了浸出渣,发现硫主要以元素硫产出。     

钢渣中钙镁离子的选择性浸出行为

钢渣富含大量的碱性氧化物,是CO₂矿化的潜在廉价原料。以乙酸作为浸出剂,探究了钢渣颗粒粒度、浸出温度、时间、固液比和乙酸浓度对钢渣中主要元素钙、镁、铁、硅溶出行为的影响。试验结果表明钢渣颗粒粒径的降低、乙酸浓度的提高均能有效促进钙、镁离子的浸出,同时也发现延长浸出时间反而会带来铁、硅离子浸出率的降低。在乙酸浓度为1 mol/L、浸出温度为80 ℃、浸出时间为90 min、固液比为1∶20的条件下,能够实现钢渣中钙、镁离子的选择性高效浸出,其最高浸出率达到了92%和52%,而铁离子、硅离子为29.5%和15.9%。浸出渣的物相分析表明经乙酸浸出后滤渣中主要的物相为RO相与磁铁相,这意味着乙酸酸浸不仅能够高效浸出钙、镁,其浸出液能够作为CO₂间接矿化的原料,而且浸出后得到的滤渣中富含含铁相,可以作为优质的炼铁原料。     

碳锰渣分段加酸浸出制取硫酸锰试验研究

通过碳锰渣浸出硫酸锰试验,分析碳锰渣化学成分,研究初始酸浓度、补酸浓度、矿酸比、温度、时间、碳锰渣碱度及添加剂对浸出率的影响,在综合条件下全锰浸出率在93%以上。     

转炉炉壳热应力分析

根据实际转炉建立实体模型。以有限元为手段,考虑了炉衬和炉壳材料的物性参数随温度变化的特点和炉衬与炉壳之间膨胀间隙,计算了转炉炉壳在温度载荷和炉衬膨胀压力同时作用下的热应力。所得结果可为转炉炉壳设计提供依据。     

Concept of freedom of infection of animal flocks

Totally negative results of epidemiological investigation of random samples do not prove the absence of the infection as the pathogen may be restricted to only a few animals in the herd for a long time. The statement "absence of infection" is critical for such situations. The question is raised, whether the statement "absence of infection" should be generally avoided. Classification of herds and flocks according to the prevalence of the pathogen would be more valid for the implementation of control measures.     

显微维氏硬度测量不确定度评定

对显微维氏硬度测量不确定度进行评定，建立了不确定度计算的数学模型，确定了影响实验结果的各项因素，计算出了各因素的标准不确定度，得出结果的扩展不确定度，并给出最终测量结果的表达式。     

The effect of amount of possession of the trait of hostility on accuracy of perception of hostility in others.

Some theories of personality hold that an individual's perception of others is influenced by his own personality characteristics; more specifically, that a trait of low social value will be projected more into others, and that insight into the possession of these characteristics reduces this distortion. These 2 hypotheses were tested by having a group of college students rate each other (including themselves) on degree of friendliness or hostility. Agreement with group rating about self yielded the insight score. In general, the hypotheses were supported; the "friendly" Ss were most accurate in their perception of others, and insight was positively associated with accurate perception. From Psyc Abstracts 36:04:4HL16M. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Comparison of rates of infection of two methods of emergency ventricular drainage

The rates of infection of two methods of external ventricular drainage in use at Atkinson Morley's Hospital--namely, (a) percutaneous drainage with Rickham reservoirs and (b) tunnelled ventriculostomies--were compared in this retrospective review. Percutaneous drainage of CSF with Rickham reservoirs was associated with a 27% rate of infection as identified by positive microbiological cultures; tunnelled ventriculostomy catheters had a 10% infection rate. The difference in the infection rate between the two methods was statistically significant (P < 0.015). Other variables examined, including the age and sex of the patients and the reasons for ventricular drainage, were not associated with an increased rate of infection. Most infections from either method were caused by a coagulase negative staphylococcus. The average duration of ventricular drainage before identification of positive cultures was 5.7 days for Rickham reservoirs and 6.0 days for ventriculostomies.     

浅析《野草》的版画特征

鲁迅先生一生热爱美术作品,对版画中木刻兴趣尤甚.<野草>作为其"写心之作",亦呈现出一些与木刻版画一致的审美特征:一是具有木刻版画的色彩特征,多对比、多冷色,有阴郁的美感;二是具有木刻版画的力度特征,环境描写、人物刻画处处刀锋毕现,遒劲有力,有一种"力之美".     

四辊破碎机车刀架的改造

针对四辊破碎机车刀架车削中存在的几个问题,详细介绍了电动车刀架的结构和工作原理,建立主要设计参数的数学表达式,并进行适当的分析。改造后,这种电动车刀架运行平稳、可靠、方便、省力,取得了预期的效果。     

2008年中国电解金属锰发展态势浅析

对中国电解金属锰发展的市场态势、价格行情以及原材料供应情况作了初步分析,提出我国电解金属锰行业挑战与机遇并存,只要抓住机遇、迎接挑战、夯实基础、科技创新,电解金属锰行业前景将会更加光明。     

Replication of dimensions of locus of control.

Employed 120 male and 113 female undergraduates in a replication of H. L. Mirels's (see record 1970-10386-001) study which found 2 factors in analyzing responses to 23 items on Rotter's Internal-External Control Scale. The same polar dimensions of "luck" as the arbiter of life events as opposed to personal control were found as well as a 2nd dimension of degree of control over political and social institutions. (PsycINFO Database Record (c) 2010 APA, all rights reserved)