在建水电工程安全文化示范企业创建的实践

澜沧江公司在建施工工程较多,由于人的违章行为导致的物的不安全状态,如违章摆放的施工用具或设备、未经许可的擅自作业行为、未采取保护措施的作业行为等也是客观存在的,随着经济的发展,设备的本质安全水平不断提升,作业环境也逐步得到改善。但是,水电施工的安全风险仍无处不在,居高不下,设备的本质安全和作业环境的改善只能解决一部分问题,最终归结点仍在人的不安全行为上。因此,安全文化的推行是水电建设安全管理上台阶的最重要手段,也是实现本质安全的根本方法。     

东北地区火电厂项目水土保持监测

本文结合大唐长春第三热电厂新建工程水土保持监测经验。分析东北地区火电厂项目建设过程中的水土流失危害及影响,提出水土保持监测工作的方式方法、对策及建议。     

Evidence for internal phosphorus loading,hypoxia and effects on phytoplankton in partially polymictic Lake Simcoe,Ontario

Hypoxia and cyanobacterial blooms were extensive in Lake Simcoe during the 1980s and are still a problem to a lesser degree despite extensive nutrient load reduction from the catchment basin. The continuing signs of productivity indicate a potential internal phosphorus (P) source. Internal P load, as a redox-dependent release from bottom sediments, is hard to determine in a large, relatively shallow and partially unstratified lake such as Lake Simcoe. Of the lake's three major basins, only Kempenfelt Bay stratifies long enough to develop hypoxia in the stagnant summer hypolimnion. The following indications of sediment P release are available from historic data: 1) hypolimnetic hypoxia still occurs in Kempenfelt Bay although the hypoxic factor (number of days that an area equal to the bay's surface area is overlain by water of ≤ 2 mg/L dissolved oxygen, DO) has decreased substantially and significantly from 15.8 d/yr (1980–1994) to 4.0 d/yr (1995–2011); 2) hypoxic factors for other lake sections and at different DO levels also indicate widespread hypoxia; 3) concentrations of redox dependent metals, Fe and Mn, increase with depth; and 4) euphotic zone P and chlorophyll concentrations increase and water clarity decreases during fall turnover. Cyanobacterial blooms appear to occur in response to internal load as supported by occasional cyanobacteria counts. These indicators provide evidence that internal loading is likely occurring and affecting the water quality in Lake Simcoe. We expect that further monitoring, specific for internal load, will corroborate these results.     

河床式电站大坝泄洪流场的三维数值模拟

 在1∶100水工模型试验的基础上,应用k-ε流数值模型,采用VOF方法,对低水头大流量河床式电站大坝泄洪流场进行了三维数值模拟。将计算得出的各工况下泄洪闸闸室及下游流场的流态,水面线,闸室内流速、压力分布等水力特性值与试验数据对比,发现计算值与试验值基本吻合。说明所选择的紊流数学模型,建立基本控制方程以及求解数学模型的离散方法是比较可靠的,可以为工程设计提供参考。     

引洮供水一期工程总干渠糙率原型观测(1)——研究方法与水位、流量监测

 大型长距离输水工程的糙率是工程设计中的关键参数,随着工程施工技术的进步,工程建成后的实际糙率小于规范值,但设计中如何减小糙率取值则无选择的依据。为了给引洮供水工程优化设计提供依据,甘肃省引洮水利水电有限责任公司于 2006 年立项进行糙率原型观测研究,原型试验工程选择 1995 年建成的甘肃引大灌区总干渠和东二干渠,原型观测隧洞试验段分别在 30 A 隧洞出口与盘道岭隧洞进口修建机翼形量水槽,采用自动监测系统实时监测流量,隧洞水位各设 6 个观测断面,并采用水位自动监测系统实时监测。两处明渠段糙率原型观测试验水位流量采用人工方式进行。本文为该项研究的第一部分。     

Thermal stability of SiC Schottky diode anode and cathode metalisations after 1000 h at 350 °C

The thermal stability of two commercially available silicon carbide Schottky diode types has been evaluated following a 1000 h non-biased storage test under vacuum at 350 °C. The Ti-based Schottky (Anode) contact shows excellent stability over the duration of the test with less than 5% change in either extracted Schottky barrier height or ideality values. The Al die attach metalisation on the anode also shows no evidence of degradation after the test. However, a considerable change in series resistance was observed for both diode types, with up to a factor of 100 measured for one of the diodes. The primary early failure mode is related to degradation of the NiAg Ohmic (cathode) die attach metalisation. Demixing of the NiAg alloy, leading to Ag agglomeration is proposed to be the underlying degradation mechanism involved resulting in delamination of the die attach metalisation and the corresponding series resistance increase.     

Transparent ceramics for high-energy laser systems

We demonstrate that transparent magnesium aluminate spinel ceramic possesses excellent thermo-optical properties, a record low absorption loss of 6 ppm/cm, and superior ruggedness which position it as a prime candidate for an exit window aperture for high energy laser systems, especially in hostile environments. We also demonstrate lasing with an efficiency of about 45% in transparent Yb³⁺:Y₂O₃ ceramic made by hot pressing high purity submicron co-precipitated powder. This paves the way forward for high power solid state lasers exploiting hosts with higher thermal conductivity than YAG.     

Training and dissemination of cognitive behavior therapy for depression in adults: A preliminary examination of therapist competence and client outcomes.

Objective: In this study, the authors examined the feasibility and effectiveness of training community therapists to deliver cognitive behavior therapy (CBT) for depression. Method: Participants were therapists (n = 12) and clients (n = 116; mean age = 41 years, 63% women) presenting for treatment of depression at a not-for-profit and designated community mental health center for St. Joseph County, Indiana. The training model included a 2-day workshop followed by 1 year of phone consultations. CBT competence ratings from the Cognitive Therapy Scale were obtained prior to training and at 6 and 12 months posttraining. Two different groups of clients, a treatment-as-usual (TAU) group (n = 74) and a CBT group (n = 42), were compared with respect to decrease in symptoms of depression (assessed with the Beck Depression Inventory) and anxiety (assessed with the Beck Anxiety Inventory). Results: Therapists showed significant increases in total scores from pretraining to 6 months posttraining, increases that were maintained at 12 months. The increase in the total score reflected gains on items that specifically measure CBT skills and structure. Although both TAU and CBT resulted in a significant decrease in depressive symptoms, the CBT clients showed significantly greater change than the TAU clients, F(2, 113) = 53.40, p     

The grain refining mechanism of C-Mn steel by CSP

The grain refining mechanism of C-Mn steel sheet on compact strip production(CSP) line was investigated in this study.The grain was about 100μm after F1 pass and decreased all the way of the rolling process(F2-F6) to 15μm.Repeated phase transformation experiment was conducted to the steel for grain refinement.The phase transformation at 860℃and 920℃can refine the grain size to 7.5μm.     

国内外甲醛行业发展情况

介绍了国内外甲醛的供需情况,阐述了甲醛生产技术的进展,分析了我国甲醛行业的特点.