提钒尾液回收硫酸钠、硫酸铵的研究

以某企业现场提钒尾液蒸发浓缩结晶物为原料,采用中温焙烧技术回收其中的硫酸钠、硫酸铵。中温焙烧主要采用闪蒸干燥一回转窑焙烧,使混合结晶物中的硫酸铵分解以获得纯度较高的硫酸钠。结果表明,闪蒸干燥后原料中水分可由20％降至1％;回转窑焙烧温度为400℃、焙烧时间为0．5h时,焙烧产物中硫酸铵含量可降至1％以下。回收所得硫酸钠可作为硫化钠生产原料;所得副产物氨气、二氧化硫和三氧化硫（少量）可制成硫酸铵返回钒氧化物沉淀工序使用。     

真空条件下电解TiO_2制备海绵钛电解电压的研究

研究了真空条件下直接电解TiO_2制备海绵钛过程中的电解电压。从理论上系统研究了真空状态对TiO_2和CaCl_2理论分解电压的影响,实验研究了TiO_2实际分解电压以及电解电压与产物纯度的关系。研究结果显示,在1200 K、10 Pa时,TiO_2和CaCl_2理论分解电压分别为2.51 V和3.86 V,TiO_2实际分解电压为2.53V,超电压为0.2V,考虑到加快电解速率和提高电解产物纯度,真空条件下电解电压的最佳范围在2.9～3.5 V之间,在此条件下进行电解,电解产物海绵钛的纯度达99.5%以上。     

硫酸锰固相分解制备高纯Mn3O4

用TG-DSC结合XRD分析研究了硫酸锰的热分解过程。实验考察了温度、时间和冷却方式等因素对硫酸锰分解产物总锰含量的影响。实验结果表明,通过控制固相分解的工艺条件,可制备高纯Mn3O4。在较佳条件下制备的Mn3O4产物为γ-Mn3O4,总锰含量71.8%,含硫0.005%,硫酸锰分解接近完全。     

硫酸钠、碳酸钠杂质对铝酸钠溶液晶种分解过程的影响

试验研究了工业铝酸钠溶液中硫酸钠、碳酸钠的存在对铝酸钠晶种分解率、分解产品粒度和产品强度的影响。试验结果表明,硫酸钠和碳酸钠的存在对晶种分解有抑制作用,二者浓度增大会使产品粒度增大;二者浓度不同则产品强度不同。     

电场对铝酸钠溶液晶种分解过程的影响

研究了电场对铝酸钠溶液晶种分解过程的影响,考察了不同温度和苛性碱质量浓度条件下电场对铝酸钠溶液非晶种分解过程和晶种分解过程的影响,并用扫描电镜、X-射线衍射仪分析了分解产物的形貌和物相组成。试验结果表明:铝酸钠溶液的分解率在电场作用下显著提高;电场能促成大量初生晶核的形成,以及一些大颗粒氢氧化铝的附聚,缩短了成核诱导期;电场不会改变铝酸钠溶液分解产物的物相。     

氟碳铈精矿的煅烧分解

本文研究了温度和粒度对氟碳铈精矿煅烧分解速率的影响，确立了保证氟碳铈精矿煅烧分解完全的温度和时间条件，对不同分解温度下的煅烧产物进行了鉴定和分析。     

从硫酸稀土溶液中回收稀土金属的工艺研究

研究了硫酸钠复盐法回收硫酸稀土溶液中稀土元素镧和铈的工艺,考察了反应时间、反应温度、硫酸钠用量和溶液pH值对稀土回收率的影响。通过单因素条件实验和正交实验获得优化工艺条件如下:反应时间120s、反应温度65℃、无水硫酸钠与稀土元素的质量比5.2∶1、硫酸稀土溶液pH值2.0;在此条件下稀土元素的总回收率可达95%以上。用X射线衍射仪对制备的稀土硫酸钠复盐进行表征,确定了所得复盐为镧系硫酸钠复盐,且纯度较高。     

偶氮二甲酰胺热分解机理及氧化锌对其分解的影响

采用TG-MlS联用仪表征了不同温度下偶氮二甲酰胺热分解的气体种类,红外光谱表征了偶氮二甲酰胺在不同温度下的分解残留物,探讨了偶氮二甲酰胺的热分解机理以及氧化锌对其分解的影响.研究表明,偶氮二甲酰胺热分解过程分为3个阶段:第一阶段的气相产物为N2、CO、HNCO,固体残留物为联二脲等;第二阶段的气相产物为NH3、HNCO;第三阶段的气相产物为NH3、CO2,固体残留物为尿唑等.ZnO的加入使得偶氮二甲酰胺热分解的第一阶段反应提前,第二阶段反应和第三阶段反应滞后.     

氟碳铈矿分解脱氟过程研究

采用X射线衍射(XRD)和热重-差示扫描量热分析(TG-DSC)等手段对氟碳铈矿焙烧分解和脱氟过程进行了研究.从600～1000℃对氟碳铈矿分别在空气气氛和饱和水蒸气气氛条件下进行了焙烧实验,对焙烧产物进行了XRD分析,并测定了每个焙烧条件下氟的脱除率,用扫描电镜(SEM)对600℃和1000℃焙烧产物进行形貌对比.通...     

氧化沉淀法从稀溶液中分离锌钴

以过硫酸钠为氧化剂,采用氧化沉淀法从除铁后液中分离锌钴,探讨了各因素对氧化沉淀的影响。结果表明,在过硫酸钠用量为钴理论耗量4倍、温度80℃、pH 4.8⁵.0、氧化时间3h的最佳条件下,钴完全氧化沉淀,酸洗后渣中钴含量达15.6%,钴富集了近9倍。沉钴后液用碳酸钠中和沉淀可得到含锌51.78%的碱式碳酸锌。     

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。     

焦炭热性能指标意义浅析

通过对焦炭在高炉内的历程及其变化规律的剖析,阐述焦炭热性能指标的意义,形象地把焦炭在高炉内的损耗分为三部分(M1,M2,M3)。指出M2对焦比及焦炭价格有一定的指导作用。     

Results of treatment of cancer of the cardia

Cancer of the cardia is traditionally discussed with cardiac cancer of the lower portion of the esophagus and upper gastric cancer invading the esophagus, and the specific characteristics of cancer of the cardia have never been clearly defined. We reviewed the outcome of 172 patients with adenocarcinoma of the cardia who had undergone radical surgery between 1949 and 1994 in the Division of Gastrointestinal Surgery of the Cancer Institute Hospital. The centers of the tumors were located within 2 cm above and below the boundary between the esophagus and the stomach, and their longitudinal diameter was less than 8 cm. We divided the patients into an early period (1949-1979; n = 79) and a late period (1980-1994; n = 93), and focused on the historical transition. There were no differences in patient gender or histology between the two periods. However, the late period was associated with fewer cases of esophageal invasion and shorter longitudinal diameter, as the age of the population advanced. The number of advanced cancers such as the localized and infiltrative type had decreased, and early cancer and early clinical stage had become more common, but despite the fact that the number of early cancers had increased, extended dissection, such as thoracic and paraaortic lymph node dissection, was performed more frequently. By clinical stage, the long-term outcome markedly improved in Stage I patient in the late period, and tended to improve in Stage II and III patients. This appears to have been attributable to the prevention of micrometastasis by extended dissection, although the number of early cancers is another major potential cause. There were no differences in the outcome of Stage IV patients between the two periods, and further advances in multimodality therapy must be awaited. The range of resection is basically proximal gastrectomy, and if there are adequate indications, the prognosis is favorable. In view of the status of lymphatic flow and lymph node metastasis, and long-term results, lateroaortic lymph node dissection is important. Since the number of early cancer patients has been increasing, if intraabdominal recurrence is prevented, intrathoracic lymph node dissection will contribute greatly to the outcome of such patients.     

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。     

Effect of antibiotics of chemotaxis of human leukocytes

The effect of 20 different antibiotics on chemotaxis by human neutrophils was studied. Human leukocytes incubated with chloramphenicol, rifampin, sodium fusidate, and tetracyclines in vitro showed markedly depressed migration. The mechanisms by which these antibiotics affect leukotaxis are discussed.