抑制混合型稀土精矿焙烧过程中氟逸出的研究

利用气相色谱技术研究含混合稀土精矿焙烧过程中氟逸出的问题,分别对混合稀土精矿和加入一定量CaO-NaCl-CaCl2助剂的混合稀土精矿在400～750℃下焙烧30～120min的各个条件进行实验,测出不同条件下焙烧气体中的氟总量、逸出率、分解率以及焙烧产物的物相组成。结果表明:70%的环境湿度下,焙烧混合稀土精矿过程中氟的逸出率随焙烧温度和时间的增加而增大,其中焙烧温度的影响较大,750℃下焙烧2h时可达29.952%;添加CaO-NaCl-CaCl2助剂不仅降低了混合稀土精矿的分解温度,使混合稀土精矿在700℃下焙烧2h的分解率在90%以上,更重要的是抑制了焙烧过程中氟的逸出,使氟的逸出率由19.296%下降为0.315%,相对抑制作用为98.37%。     

钢中稀土夹杂物与金属相中稀土测定

钢中的稀土在通常的加入量下,绝大部分部以稀土夹杂物的形态存在,即使在金属相中含有稀土,也是非常微量的.因此要判断金属相中是否有稀土或要测定金属相中的稀土,都必须选择一种具有灵敏度高、选择性好、操作简便的分析方法.我们引用DBC-偶氮胂显色剂,不经分离即可直接测定,而且灵敏度大大提高.一、主要试剂和仪器DBC-偶氮胂溶液:0.05%水溶液;稀土标准溶液;1μg/ml(按La+Ce+Pr+Nd+Sm=30+50+10+8+27)配制;     

09CuPTiRE钢板坯连铸时结晶器喂稀土丝的应用

试验了铸速 0 .70～ 0 .90m min结晶器喂直径 2 .5mm稀土丝的 0 9CuPTiRE钢板坯连铸工艺。稀土在 1 2 5 0mm× 2 0 0mm板坯上分布均匀 ,最大值为 0 .0 39% ,最小值为 0 .0 2 6 % ,稀土回收率≥ 80 % ,显著改善0 9CuPTiRE钢板的横向冲击性能     

热加工工艺对医用TC4合金棒材显微组织的影响

研究了热加工工艺对医用TC4合金大规格棒材显微组织的影响。研究结果表明:采用单一的拔长变形方式或单一的镦拔变形方式,不能全面解决医用TC4合金大规格棒材生产过程中经常出现的显微组织不均匀和成品率低下等问题;采用温度梯度镦拔组合变形工艺(Tβ+(30～70)℃镦拔,变形量50%→Tβ-(10～30)℃镦拔,变形量50%→Tβ-(30～70)℃镦拔,变形量50%),可以有效改善精锻用原始棒坯的组织,从而获得具有均匀细小等轴组织的医用TC4合金70 mm棒材。     

离子型稀土浸出液复合钠盐高效富集稀土

为实现无铵富集稀土,以复合钠盐为沉淀剂,对铝盐体系离子型稀土矿浸出液中稀土进行富集。考察了pH对稀土浸出液除铝效果的影响,研究了不同沉淀剂、沉淀剂配比及用量、终点pH、反应温度、反应时间、陈化时间对稀土沉淀率的影响。结果表明,在初始稀土浓度0.014 64 mol/L、铝浓度0.54 g/L、初始pH=3.89、反应温度25 ℃、反应时间60 min的条件下,除铝终点pH=4.93时,残余铝浓度为13.02 mg/L,稀土损失为1.2%;当复合沉淀剂用量为0.7倍理论量的70%NaHCO3+30%Na2CO3、沉淀终点pH=6.72、反应时间60 min、反应温度25 ℃、陈化时间40 min时,稀土沉淀率高达99.68%,灼烧后氧化稀土总量为96.48%,铝含量为0.52%。     

稀土铝合金在硫酸、草酸溶液中的阳极氧化

本文对添加稀土的铝合金在硫酸和草酸溶液中进行了阳极氧化,比较系统地作了电解液浓度、湿度、电流密度、氧化时间诸因素对氧化膜厚度影响,试验结果表明:稀土铝合金膜层致密,稀土含量为0.29%时为宜;并研究了影响膜厚度的诸因素,找到了较好的工艺条件。     

纳滤浓缩稀土母液沉淀上清液的实验研究

以赣州某稀土公司浸矿所得稀土母液经NH₄HCO₃除杂沉淀后的上清液为处理对象,主要研究纳滤技术对原液中稀土离子的浓缩效率,以及对NH₃-N分离回收情况,以期能够为工业化分离应用提供借鉴.实验表明,当原液中稀土离子浓度为142.9 mg/L,氨氮浓度为346.1 mg/L时,在操作压力为0.8 MPa,进水pH值为6.49,运行温度为25 ℃的条件下,浓缩液侧稀土离子截留率达到95 %以上,Ca2+、Mg2+、Mn2+、Zn2+等杂质离子截留率能够达到75 %~90 %,透过液侧氨氮浓度为原浓度的60 %左右,有一定的浓缩效果;6.0 L的稀土母液沉淀上清液浓缩至0.6 L时,RE3+浓度升高至1 242.0 mg/L,浓缩了近8.69倍.      

浓NaOH溶液分解稀土矿物的研究

本文通过对NaOH与稀土矿物(氟碳铈矿和独居石)反应的化学原理分析,较系统地研究了浓NaOH溶液在加热条件下分解稀土矿物的基本行为——反应物料的升温速度和稀土矿物的分解速度都随NaOH浓度的提高而加快,从而确定了浓NaOH溶液分解稀土矿物的最佳条件:NaOH用量为稀土精矿量的80%,NaOH浓度为70%,分解温度～160℃,分解时间30分钟。与用50%NaOH溶液分解稀土矿物的数据相比较,NaOH用量可降低25%,分解时间由4～6小时缩短为30分钟。     

稀土离子均相电催化氧化处理含酚模拟废水

以不同稀土离子为催化剂,研究了含酚模拟废水的电催化氧化降解.以COD和苯酚的去除情况作为考察指标,确定最佳催化剂及其最佳处理条件;考察了稀土离子与过渡金属离子的投配比对废水处理效果的影响,并对4种稀土催化剂的电化学性能进行了测试.结果表明:所选稀土离子La3+、Ce4+、Pr3+、Nd3+对苯酚的氧化均有良好的电催化性能,其中Pr3+的均相电催化效果最好.在pH =3、电流密度为66.7mA · cm-2条件下,Pr3+投加 量为0.11mmol·L-1能达到最好的降解效果.在此条件下电解废水60min时,COD和苯酚去除率分别达到62.1％和76.3％,比未加催化剂分别提高35.1％和36.6％.Pr3+和Mn2+的协同作用可提高废水的处理效果,当Mn2+与Pr3+的投配比为1∶1时电催化处理效果最好.     

从废石油裂解催化剂中回收稀土试验研究

研究了从粒度小于20μm、污染较重、不适宜复活的废催化剂中回收稀土。试验结果表明:控制浸出温度60℃、盐酸浓度3.33mol/L、浸出时间3h,废催化剂中91.3%~94.5%的镧、铈被浸出;用50%P507+50%磺化煤油,在温度25℃、萃取相比V_o∶Va=2∶1、萃取时间30min条件下从稀土浸出液中萃取镧铈,镧铈萃取率为94.5%;对负载有机相,采用1.8mol/L盐酸反萃取,控制相比V_o∶V_a=1∶3,稀土镧铈的反萃取率为98.1%;对反萃取液用草酸进行沉淀,沉淀物灼烧,获得工业级氧化镧铈产品。     

Voices of fear and anxiety and sadness and depression: The effects of speech rate and loudness on fear and anxiety and sadness and depression.

Two studies investigated the role of expressive vocal behavior (specifically, speech rate and loudness) in fear and anxiety and in sadness and depression. In the 1st study, participants spoke about personally experienced fear and anxiety-arousing and neutral events using 3 different voice styles: fast and loud, normal, and slow and soft. In the 2nd study, participants spoke about personally experienced sad or depressing and neutral events using the same 3 voice styles. In both studies, the participants' highest levels of subjective affective and cardiovascular (CV) arousal occurred when they spoke about the emotional events in a mood-congruent voice style: fast and loud in the case of fear and anxiety, and slow and soft in the case of sadness or depression. Mood-incongruent voice styles canceled the heightened levels of CV arousal normally associated with these negative emotions. The voice-style manipulation had no significant effect on the participants' levels of CV arousal during the neutral discussions. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Synthesis and analysis of mixed chlorinated-fluorinated dibenzo-p-dioxins and dibenzofurans and assessment of formation and occurrence of the fluorinated and chlorinated-fluorinated dibenzo-p-dioxins and dibenzofurans

Despite the use of multimodal therapy, higher-grade glioma is still uniformly fatal in the adult population. There is a considerable difference between the length of survival in each given patient, even within the same tumor type and malignancy grade group, suggesting that there are factors that might differentially influence outcome. To identify such factors, 107 patients with anaplastic or malignant glioma were retrospectively investigated. Clinical parameters and paraclinical data on the p53, mdm2, and EGFR genes at the DNA or protein level were evaluated by univariate analysis and Cox proportional hazards regression modeling. Kaplan-Meier survival estimation demonstrated that immunohistochemical positivity for mdm2 protein in patients with anaplastic astrocytoma or with glioblastoma multiforme was associated with a shorter survival time (p = 0.02). P53 gene mutations and immunopositivity for the epidermal growth factor receptor (EGFR) protein were not significantly related to poor prognosis. The Cox proportional hazards model revealed immunohistochemical positivity for p53, mdm2, or for both of them, the presence of postoperative irradiation, and the extent of surgical resection of tumor to be variables significantly associated with prolonged survival. EGFR overexpression, age over 60 years, and Karnofsky performance score below 40 points did not significantly shorten survival time. In conclusion, the present study identified immunohistochemically detected mdm2-protein overexpression as a statistically significant negative prognostic parameter in patients bearing anaplastic or malignant glioma. Association analysis of variables revealed a possible correlation between mdm2 and p53, which is also consistent with the biological interaction mode of both proteins in vivo.     

Sexuality and aging--usual and successful

BACKGROUND: As aging research increasingly reflects an effort to dissociate true time-driven changes from those that can be improved, sexuality in later life remains largely unexplored. Several problems are evident. There is a lack of normative data, a lack of a conceptual framework relating to the biology, psychology, and sociology of sex, and an attitudinal resistance that obscures the entire topic. METHODS: We conducted a three-part instructional series on major topics involved with sexuality and aging. We surveyed our group of attendees (n 158, average age 68 for males, 65 for females) before and after the series. RESULTS: A remarkably robust sex life was evidenced by both the men and the women, even until advanced old age. Yet, a substantially decreased involvement was reported from 10 years earlier. Despite current activities, people of both sexes wished they were participating even more than they currently were. Impotency was identified as the major negative feature for the men; relationship problems were for the women. A questionnaire 6 months after the series reported improved sexual attitudes, but no change in sexual activities from the earlier survey. CONCLUSION: Sexuality is a major quality-of-life issue which persists into old age. Our study showed that the usual sexual practices reported by our group were not considered by them to be ideal. The intervention of this instructional series provided improved sexual attitudes but not performance. Additional studies are encouraged.     

Spondylolysis and spondylolisthesis and sports

Spondylolysis and spondylolisthesis occur predominantly in the lower lumbar spine. Besides congenital defects such as predisposition of spondylolysis the correlation between competitive sports activities and an increased incidence of spondylolysis is proved. In early stages, complete healing can be achieved by conservative treatment (abstinence from sports activities for 3 months, orthesis). Persistence of pain, neurologic symptoms and progression of vertebral slipping are indications for operative treatment (reconstruction of the isthmus, dorso-ventral spondylodesis). The exercise tolerance depends on the extent of instability, progression of vertebral slipping and clinical symptoms. The limits of exercise tolerance vary among the individual athletes and require the decision of the physician. Backstroke swimming, abdominal and back muscle strengthening exercises, and types of sport involving smooth movements are advisable. Sports education in school is possible without restriction in patients with stable spondylolysis and in those with spondylolisthesis without unfavourable concomitant factors.     

Larks and owls and health, wealth, and wisdom

OBJECTIVE: To test the validity of Benjamin Franklin's maxim "early to bed and early to rise makes a man healthy, wealthy, and wise." DESIGN: Cross sectional analysis of sleeping patterns in a nationally representative group of elderly people, and longitudinal investigation of mortality. SETTING: Eight areas in Britain (five in England, two in Scotland, and one in Wales). SUBJECTS: 1229 men and women aged 65 and over who in 1973-4 had taken part in a survey funded by the Department of Health and Social Security and for whom data on sleeping patterns, health, socioeconomic circumstances, and cognitive function had been recorded. MAIN OUTCOME MEASURES: Self reported income, access to a car, standard of accommodation, performance on a test of cognitive function, state of health and mortality during 23 years of follow up. RESULTS: 356 people (29%) were defined as larks (to bed before 11 pm and up before 8 am) and 318 (26%) were defined as owls (to bed at or after 11 pm and up at or after 8 am). There was no indication that larks were richer than those with other sleeping patterns. On the contrary, owls had the largest mean income and were more likely to have access to a car. There was also no evidence that larks were superior to those with other sleeping patterns with regard to their cognitive performance or their state of health. Both larks and owls had a slightly reduced risk of death compared with the rest of the study sample, but this was accounted for by the fact that they spent less time in bed at night. In the study sample as a whole, longer periods of time in bed were associated with increased mortality. After adjustment for age, sex, the presence of illness, and other risk factors, people who spent 12 or more hours in bed had a relative risk of death of 1.7 (1.2 to 2.5) compared with those who were in bed for 9 hours. The lowest risk occurred in people who spent 8 hours in bed (adjusted relative risk 0.8; 0.7 to 1.0). CONCLUSION: These findings do not support Franklin's claim. A "late to bed and late to rise" lifestyle does not seem to lead to socioeconomic, cognitive, or health disadvantage, but a longer time spent in bed may be associated with increased mortality.     

深云立交桥梁检测及加固改造

根据深云立交桥梁的检测结果，对该桥目前的整体状况、工作状态，及其使用情况做出综合评价，对桥的病害原因进行了分析，并提出合理的加固方案。     

关于摩尔浓度及其与硬度转换关系问题的讨论

众所周知，国际单位制物质的量采用摩尔(mol)表示，近几年出版的给排水专业书籍，为了与国际单位制接轨，逐渐将摩尔的使用频率不断提高，被给排水技术人员广泛应用的新版给排水设计手册，将表示物质浓度的单位“当量／升”或“毫克当量／升”．改为mol／l或mmol／l，虽然编者对其基本单元定义作了说明，但在实际运用上仍会出现误解，     

《儿子与情人》的语码转换与男女二元对立

劳伦斯小说《儿子与情人》一个鲜明的语言特色就是标准英语和当地方言频繁的语码转换。莫瑞尔用方言来对抗妻子,而妻子坚持用标准英语,偶尔也用方言来讽刺、挖苦丈夫。语码转换反映了劳伦斯男女二元对立的哲学思想。     

抗腐蚀高强耐磨涂料研发与应用

介绍了抗腐蚀高强度耐磨涂料的研制和开发，以及用作柳钢球团回转烘干机刮板保护涂层的应用效果。