羟肟酸类捕收剂的合成、性质及在稀土矿物浮选中的作用机理

介绍了羟肟酸的合成方法和性质、羟肟酸作为捕收剂浮选稀土矿物的性能及羟肟酸类捕收剂在浮选中的作用机理,研究表明羟肟酸具有良好的选择性能和捕收性能,是稀土矿物的有效捕收剂。     

羟肟酸类捕收剂在稀土选矿中的应用与研究进展

羟肟酸是一类选择性能很好的螯合捕收剂，广泛应用于氟碳铈矿和铌钽矿等稀土矿的浮选，在稀土矿的浮选中具有不可替代的作用。本文分别对烷基羟肟酸、烷基水杨醛肟、水杨羟肟酸、2-羟基-3-萘甲羟肟酸、1-羟基-2-萘甲羟肟酸、N-羟基邻苯二甲酰亚胺六种羟肟酸类捕收剂的结构、合成以及对稀土矿的捕收性能等进行了综述。     

羟肟酸类捕收剂性质及浮选钨矿物特性

通过对羟肟酸类捕收剂性质和羟肟酸类捕收剂与钨矿物作用特性的描述,表明羟肟酸浮选钨矿物最佳pH在pKa附近,此时药剂吸附量最大,ζ电位更负,羟肟酸与矿物表面金属或金属离子羟基化合物发生螯合反应。同时吸附试验结果表明羟肟酸在钨矿物表面的吸附主要为化学吸附,同时存在不均匀、物理吸附,最终形成多层吸附。     

羟肟酸类捕收剂在浮选中的应用现状及发展前景

羟肟酸是一类选择性能很好的螯合捕收剂，可广泛应用于赤铁矿、钛铁矿、硅孔雀石、锡石、萤石、黄绿石、氟碳铈矿和铌钽矿等多种矿物的浮选。本文从羟肟酸的结构、螯合性能、捕收性能、作用机理等方面对羟肟酸类捕收剂近几年的应用和发展情况进行了总结，并指出了今后的发展方向。     

羟肟酸类捕收剂的合成及其发展前景

作为一种新型的螯合捕收剂,羟肟酸已经在多种氧化矿与稀土矿物的浮选中体现了良好的选择捕收性能,并且得到了广泛的应用。本文从羟肟酸的性质及螯合性能、与矿物的作用机理等方面对羟肟酸类捕收剂进行了介绍。此外,对于羟肟酸的合成方法和发展前景也进行了总结。     

十烷基羟肟酸催化合成研究

介绍了十烷基羟肟酸的催化合成方法,以十烷基脂肪酸、甲醇、盐酸羟胺、氢氧化钠为原料,以TQ为催化剂,通过酯化、肟化、酸化三步反应制备十烷基羟肟酸。对肟化反应的配料比、反应温度、反应时间、催化剂种类、催化剂用量等因素进行了研究,产品含氮量达到5.2%。     

对叔丁基苯甲羟肟酸催化合成研究

介绍了对叔丁基苯甲羟肟酸的催化合成方法,以对叔丁基苯甲酸、甲醇、盐酸羟胺、氢氧化钠为原料,以laeo-4为催化剂,通过酯化、肟化、酸化三步反应制备对叔丁基苯甲羟肟酸。对肟化反应的配料比、反应温度、反应时间、催化剂种类、催化剂用量等因素进行了研究,产品含氮量达到5.3%。     

水杨氧肟酸和β—羟基—α—萘氧肟酸对黑钨矿捕收性能的研究

本文研究了水杨氧肟酸和β-羟基-α-萘氧肟酸对黑钨矿的捕收性能。单矿物实验表明,β-羟基-α-萘氧肟酸对黑钨矿有较强的捕收作用,在整个pH范围内不浮石英,但对方解石有较强的捕收作用,三聚磷酸钠对方解石有较好的抑制作用;水杨氧肟酸对黑钨矿也有较好的捕收作用,对石英不浮,对方解石有部分捕收作用,但在pH7.8以上时,黑钨矿的回收率迅速下降。用500mm/Lβ-羟基-α-萘氧肟酸浮选分离含WO_3 14.2％的黑钨-石英人工混合矿细泥,在pH 8.5时可获得含WO_3 56％、回收率96％的精矿。以烤胶0.50mg/L、水杨氧肟酸250mg/L浮选含WO_3 35.5％的黑钨-方解石人工混合矿细泥,在pH_9时,精矿品位为57％WO_3,回收率为68％。     

羟肟酸类捕收剂在稀土矿物浮选中的应用及发展

综述了稀土有效捕收剂羟肟酸的浮选性能及其在稀土矿物浮选中的作用机理,介绍了我国几大稀土矿应用羟肟酸选别稀土矿物的情况,讨论了羟肟酸类捕收剂在稀土矿物浮选中的发展和方向。     

N-烃基酰氨基己基羟肟酸对菱锰矿的浮选性能与吸附机理

以N-苯甲酰氨基己基羟肟酸(NO-6)、N-辛酰氨基己基羟肟酸(NO-8)和N-癸酰氨基己基羟肟酸(NO-10)三种新型的羟肟酸为捕收剂,考察了矿浆p H值、捕收剂用量对菱锰矿浮选回收率的影响。结果表明:NO-8和NO-10捕收剂的浮选性能优于NO-6捕收剂,当矿浆p H值为6~7时,NO-8和NO-10浮选菱锰矿回收率可达到90%以上;矿浆p H值更高时,浮选回收率降低;当捕收剂用量相同时,NO-10对菱锰矿的浮选回收率高于NO-8。采用红外光谱分析、Zeta电位测定和XRD分析研究了NO-8和NO-10捕收剂与菱锰矿的作用机理,结果表明,NO-8和NO-10在菱锰矿表面发生了化学吸附。     

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.     

Craniometaphyseal and craniodiaphyseal dysplasia, head and neck manifestations and management

Mechanical allodynia (MA) following hand injury is a well-documented clinical problem. The purpose of this pilot study was to examine the relationship between hand MA and the upper limb tension test (ULTT). The ULTT mechanically stresses the neural structures from the C5/6/7 neural foramina to the median nerve distally. This study examined 29 subjects with unilateral hand MA before and after a 2-week neural self-mobilization programme. There was a significant difference between the subjects' affected and unaffected sides when tested using the ULTT, both in reproduction of symptoms and in reduced range of motion of the ULTT. Following the self-mobilization program, there was an improvement in the range of the ULTT, and subjects reported a reduction in their symptoms. Complete recovery was not obtained in all cases. The results of this study suggest that the ULTT is a useful tool both in assessment and treatment of subjects with hand MA.     

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。