非调质低焊接冷裂纹敏感性钢WDB620的试制

按照焊接无裂纹钢（CF钢）的技术要求，试制了620MPa级非调质低焊接冷裂纹敏感性钢。该钢以晶粒细化，沉淀强化和贝氏体组织强化为主要手段并以微量Ti处理改善焊接热影响区韧性，具有良好的综合机械性能和焊接性能。     

铜沉淀在低合金高强度钢中的特性

1　简介低合金高强度 ( HSL A)钢 ,如海洋结构用钢HSL A- 1 0 0 ,要求强度、韧性与焊接性等综合性能。为达到这些性能 ,需在低碳钢中添加几种合金元素 ,加铜就是为了通过时效硬化来提高强度。几种参考文献中均讨论过时效期间铜沉淀的特性及强化机理。在时效初始阶段形成粘着性微细体心立方沉淀物。随着时效时间的延长 ,体心立方相转化成非粘着性面心立方铜沉淀物。当粘着性沉淀达到一个临界值 (～ 2 .4mm)时 ,出现了峰值强度。铜沉淀的量、大小和形态可影响含铜钢时效后的性能。目前 ,已试图研究等温时效期间和连续冷却过程中铜沉淀的特…     

M-A组元对低碳低合金高强度钢焊接热影响区韧性的影响

随着焊接结构的大型化以及高强度级别钢的应用日益增多,焊接结构的脆断问题越来越引起人们的高度重视。焊接热影响区脆化是低碳低合金高强钢焊接时最重要的问题之一。一般认为,存在M-A组元对焊接热影响区韧性极为不利,但是对M-A组元影响和控制热影响区韧性的机制还不十分清楚。本文目的就是探讨和研究这一问题。     

回火Q690高强钢生产工艺研究

高强度结构钢Q550D/Q690C主要应用在工程机械、煤矿机械、造船和钢结构等领域,要求具有良好的韧性、加工性能和焊接性能、耐磨、耐腐蚀等特质。文章介绍了采用微合金成分设计和TMCP控轧工艺,通过晶粒细化、沉淀强化、位错强化和组织强化等手段,辅以回火处理,得到符合用户要求的低碳贝氏体钢Q550D和Q690C的研究。对其组织和性能进行分析表明,通过选取合理的冷却工艺来保证板形、获得了预期的组织,通过回火析出强化,获得良好的强韧性指标。     

17-4PH钢的合金化及强化机制浅析

本文从17 -4PH沉淀硬化不锈钢的化学成分设计、热加工和热处理、金相组织及其性能进行了分析,阐述了17 - 4PH钢的强化机制及其影响因素.结果表明,17 - 4PH钢的强化机制特点是通过钢中各元素有效合金化,通过热处理手段使其产生热力学和动力学反应达到强化作用,使钢获得较高的强度和韧性.     

超高强度马氏体时效钢的发展

马氏体时效钢是以无碳(或超低碳)铁镍马氏体为基体的经时效生产金属间化合物沉淀硬化的超高强度钢。该钢在高强度时效处理前具有良好的成形性，时效处理几乎不变形，时效处理后有高强韧性。文中论述了典型Ni-Co-Mo-Ti-Al马氏体时效钢和Ni-Mo-Ti(-Cr-Al)无钴马氏体时效钢的化学成分和力学性能，阐述了马氏体时效钢在400～500℃时效时马氏体基体内产生大量强化效果极高、韧性损失极小的金属间化合物沉淀相的时效结构和强化机制，以及Ni、Co、Mo、Cr、Mn、Ti等元素在马氏体时效钢中的合金化作用。概述了马氏体时效钢的生产工艺，应用和发展趋向。     

高强度低合金耐磨钢NM400的强韧化机制

采用控轧控冷工艺生产的高强度低合金耐磨钢NM400,具有高强度、高硬度和较高的韧性,其屈服强度为1 170MPa,抗拉强度为1 369MPa,平均硬度为403HB,伸长率为23%,-20℃冲击功为47J。光学显微镜观察发现,NM400的组织为回火马氏体,淬透性良好;透射电镜下观察发现,钢中存在大量纳米尺寸级析出物,能谱分析表明,析出物为Ti,Nb的碳氮化物。分析结果表明,耐磨钢NM400的强化机制主要为位错强化、细晶强化和析出强化;细晶强化是韧性提高的主要原因。     

压力钢管甩低焊接裂纹敏感性高强度WDB620钢板

WDB620是舞钢生产的压力钢管用低焊接裂纹敏感性高强度钢板，采用国际低合金高强度钢的先进设计思想和研究成果，运用微合金化原理和控制轧制工艺开发的超低碳贝氏体钢。WDB620钢具有理想的强度、塑韧性指标及优良的焊接性能，达到或超过了同类进口产品的水平，广泛应用于水电站压     

压力钢管用低焊接裂纹敏感性高强度WDB620钢板

WDB620是舞钢生产的压力钢管用低焊接裂纹敏感性高强度钢板，采用国际低合金高强度钢的先进设计思想和研究成果，运用微合金化原理和控制轧制工艺开发的超低碳贝氏体钢。WDB620钢具有理想的强度、塑韧性指标及优良的焊接性能，达到或超过了同类进口产品的水平，广泛应用于水电站压     

压力钢管用低焊接裂纹敏感性高强度WDB620钢板

WDB620是舞钢生产的压力钢管用低焊接裂纹敏感性高强度钢板，采用国际低合金高强度钢的先进设计思想和研究成果，运用微合金化原理和控制轧制工艺开发的超低碳贝氏体钢。WDB620钢具有理想的强度、塑韧性指标及优良的焊接性能，达到或超过了同类进口产品的水平，广泛应用于水电站压力钢管、大型工程机械设备。     

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。