城市边缘区水环境质量演变及其城市化响应——以广东省广州市花都区为例

研究了广州市花都区近15年来水环境质量变化的过程和阶段特征,探讨了城市化对于地表水环境质量的影响机制.结果表明,1994～2007年,研究区地表水环境质量呈现明显下降趋势,2007年所监测断面除白坭外均为劣V类水质,对研究区乃至广州市用水安全造成严重威胁.全河段污染物以有机污染物为主,主要来源于电镀、漂染等高污染行业、生活废水和第三产业废水的排放.研究区污染处理设施建设严重滞后,造成污染物直排入江河,加剧了水环境质量的恶化.因此,建议通过调整工业结构、提升污水处理能力和控制农业污染等措施来改善地表水环境质量.     

沿海平原河网地区纳污能力分析——以海门市为例

水体纳污能力是科学合理地制定水污染控制规划的基础.沿海河网地区水系复杂,水体具有水深较浅、流速缓慢、顺逆不定和水体自净能力不强等问题.以沿海平原河网地区的海门市水环境为研究对象,根据其水系特点和实际需要建立-维河网水量水质模型,在此基础上计算了该市主要河道的纳污能力,为当地的水环境管理提供科学依据.     

杭州市下沙高教园区景观水体水质特征及分析

在高教园区内选取了19个有代表性的景观水体采样点,76个采样断面,在2007～2009年不同水文季节对各景观水体进行水质监测分析.结果表明,各景观水体水质在不同水文季节呈现一定的动态变化.综合分析了高教园区内景观水体的水环境特征,剖析了景观水体总磷、色度、pH3个主要污染因子,为下沙高教园区景观水体水质的管理维护提供了基本资料.     

基于多种库岸再造预测方法的分析及应用

水库库区蓄水后,势必造成库岸再造,对库岸边坡稳定性影响很大;而库区公路工程为线性工程,受库岸再造影响段落较长,受影响的情况也多种多样。本文以溪古水电站库区复建公路工程K245+380～K246+100段为实例,分别采用Е·Г·卡丘金法及Г·С·佐洛塔寥夫法对该段库岸再造影响进行预测分析,并通过比较得出该地区计算法比图解法的预测结果偏于保守的重要结论。     

南方某河流水环境问题分析及防治对策建议

对南方某河流水环境质量现状进行了阐述,结合该河流2014年至2020年国控断面的逐月水质监测数据(包括化学需氧量、氨氮、总氮、总磷、水温)和季节性Kendall趋势检验方法,研究了该流域的水质变化趋势.通过分析水体存在的问题,提出了相应的水资源管理保护和水污染防治措施,旨在为中小型流域水环境污染综合治理提供对策建议.     

金华江小流域氨氮污染状况分析及控制对策探讨

通过对金华江小流域水质状况、污染成因、上游小支流氨氮污染沿程分布以及不同支流汇入交接断面污染现状分析和跟踪分析调查,以及对金华江近十年上下游氨氮污染变化趋势进行研究,据此提出具体氨氮污染控制对策以及可实施的流域管理技术与方法.     

良山铁矿尾矿坝的生产管理

良山铁矿南桥尾矿库于1977年投入使用,设计有效库容450万m~3,尾矿最终堆坝标高为125m,库区汇水面积0.53×10~6m~2,排洪系统最大泄洪能力为1.75m~3/s,初期坝为均质土坝,尾矿堆积坝为上游法堆坝,平均外坡为1:3,内沉积滩平均坡度为0.01,至1988年底堆积坝堆存标高达117m,堆存尾矿455万t,约占总库容的67％。承     

高拉速板坯结晶器流场影响因素的模拟研究

采用1∶1物理模拟和数值模拟相互验证,分析了拉速、水口插入深度和断面宽度对结晶器流场的影响。结果表明,当断面为230 mm×1 490 mm,插入深度为150 mm时,拉速从1.3 m/min增加到1.7 m/min,最大表面流速从0.21 m/s增加到0.32 m/s,液面波动平均增幅为21.1%;当断面为230 mm×1 490 mm,拉速为1.7 m/min时,水口插入深度从190 mm降低到150 mm,最大表面流速从0.26 m/s增加到0.32 m/s,液面波动平均增幅为30.6%;结晶器断面宽度从940 mm增加到1 490 mm,由于通钢量增大,液面流速和液面波动都增大;各因素改变时,角部流速的增幅远小于其他部位流速增幅,角部在流场中属于死区;通过物理模拟研究可得,影响液面流速最大的因素是拉速,影响液面波动最大的因素是断面宽度。     

虹吸管在酸性水库取水工程中的应用

传统的取水方式通常需要消耗电能,或对地形地质条件要求较高,产生大量开挖及边坡支护工作,或管道穿越防渗层造成防渗层失效.虹吸管利用上游水面和管内的压差,可将水流从上游库高处跨过高地引向低处,避免管道穿坝破坏防渗层,是较好的取水方式.某酸性水库拦挡坝坝面及库区均采用HDPE土工膜防渗,为避免破坏防渗系统并节约能源,设计采用...     

循环水系统采用高氨氮、高COD、高TDS补水的研究与应用

<正>地下水以其稳定的供水条件、良好的水质,成为农业、工业以及生活用水的重要水源,随着社会经济的发展,地下水资源的污染也逐渐加剧。根据《2017中国生态环境状况公报》,全国5100个水质监测点中,较差级和极差级的地下水占2/3,取用受污染地下水会对生产的稳定运行造成较大隐患。一、系统运行状况某钢铁有限公司双曲线循环水系统保有水量27800m³,4～9月循环水总量平均为33000m³/h、10月～次年3月循环水总量平均为26800m³/h,为23000m³/h制氧站、鼓风机站、15MW发电、     

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。