Ten complementary measures to assist with environmental watering programs in the Murray–Darling river system,Australia

Restoration programmes for degraded aquatic ecosystems frequently focus on flow restoration or reinstatement, including recovery targets for volumes of water to be used for environmental benefit. Australia's Murray–Darling Basin is an example of a major system undergoing substantial water reform to balance the needs of competing users, including the environment, within the constraints of an arid climate. This reform revolves around accounting for finite volumes of water that have been shared amongst water users. We argue that while recovering water will provide good outcomes, as a sole intervention, it is not enough to deliver the desired environmental benefits of the reform given the significantly altered state of the catchment. Here, we present 10 measures that could be used to complement planned water recovery actions. These “complementary measures” integrate recovery actions, which when strategically combined with water delivery would significantly enhance water reform efforts to generate environmental outcomes in a highly modified system.     

分体滑动导叶可调涡轮激波与载荷波动机制

针对某柴油机用可调涡轮在低速工况下的低效强激波特征，提出并设计了一种分体滑动导叶，并在10%、40%和100% 3个典型开度下进行了定常/非定常数值计算。结果表明：分体滑动导叶在小开度下可实现对间隙泄漏流动的有效抑制，大幅度提高涡轮效率；在10%开度下，分体滑动导叶提高了涡轮10%的峰值效率，同时涡轮效率在40%和全开工况下也有不同程度的提高。此外，通过合理设计转静间距，分体滑动导叶尾缘激波被大幅度削弱。导叶间隙泄漏流和尾缘激波的抑制可有效弱化转子定子干涉强度，降低下游转子叶片表面载荷波动幅值，提高转子叶片的可靠性。     

基本公共服务均等化背景下吉林市社区养老问题研究

近年来，以推进基本公共服务均等化为依托而促进养老等社会服务的发展已成为各省市的重点工作之一，立足于吉林市市情，通过调查研究、定量分析等方式探索本地社区养老存在的问题以及对策。     

碳酸钠浓度对废电池铅膏脱硫影响机制与动力学

以铅膏为研究对象，采用碳酸钠为脱硫剂，系统研究了碳酸钠浓度对铅膏脱硫率及铅收得率的影响，并借助化学分析、扫描电镜分析仪（SEM-EDS）、X射线衍射分析仪（XRD）揭示了铅膏脱硫反应机理，计算了动力学参数。结果表明，铅膏脱硫率随碳酸钠浓度的增加而增大，而铅收得率变化规律相反。铅膏主要由硫酸铅及铅的氧化物组成。在碳酸钠浓度小于0.150 mol/L时，脱硫产物中主要以PbCO₃和Pb₃（CO₃）₂（OH）₂形式存在；随着浓度的增加，PbCO₃不断向Pb₃（CO₃）₂（OH）₂转化，并最终转化为NaPb₂（CO₃）₂（OH）₂，导致铅收得率降低。铅膏脱硫过程活化能随浓度的增大而减小，受化学反应控制。浓度低于0.208 mol/L时，活化能降低幅度较大，由7.275 kJ/mol降至5.312 kJ/mol，之后活化能随浓度的增加变化程度较小。     

复合添加剂对钒电池正极电解液性能的影响

为了提高钒电池电解液的性能，选取了3种复合添加剂，研究了复合添加剂对钒电池正极电解液稳定性和电化学性能的影响。利用电化学方法制备了2 mol/L的全钒液流电池正极5价钒离子电解液，采用临界胶束浓度法得到复合添加剂的配比为：1% KHSO₄+3 mmol/L SDBS（十二烷基苯磺酸钠）、1% KHSO₄+2 mmol/L D-山梨醇、1% KHSO₄+2 mmol/L CTAB（十六烷基三甲基溴化铵），并考察添加剂加入电解液后的稳定性与电化学性能。通过XRD分析手段，对电解液沉淀物的成分进行了表征。研究表明：添加剂的加入，并不会引起钒离子价态的变化，1% KHSO₄+2 mmol/L CTAB加入后，电解液峰电位差减小12 mV，峰电流增加9.8 mA，说明CTAB与KHSO₄在合适配比下，能够有效提高正极电解液的稳定性及可逆性，添加剂的引入并未引起电解液沉淀物的物相组成变化，电解液性能显著提高。     

Prediction of curved oil–water interface in horizontal pipes using modified model with dynamic contact angle

In this study, interface shapes of horizontal oil–water two-phase flow are predicted by using Young-Laplace equation model and minimum energy model. Meanwhile, the interface shapes of horizontal oil–water twophase flow in a 20 mm inner diameter pipe are measured by a novel conductance parallel-wire array probe(CPAP). It is found that, for flow conditions with low water holdup, there is a large deviation between the model-predicted interface shape and the experimentally measured one. Since the variation of pipe wetting characteristics in the process of fluid flow can lead to the changes of the contact angle between the fluid and the pipe wall, the models mentioned above are modified by considering dynamic contact angle. The results indicate that the interface shapes predicted by the modified models present a good consistence with the ones measured by CPAP.     

Surface wettability and flow properties of non-metallic pipes in laminar flow

In this paper, three liquids flowing in five pipes with the same inner diameter of 14 mm were studied to determine the relationship between the surface wettability and flow properties in laminar flow(Re b 2000). This was motivated by oilfield observations of increased pressure drops in non-metallic pipes compared to those in metal pipes,which was contrary to expectations. A new expression for the frictional coefficient that considers the Reynolds number and contact angle θ in laminar flow for non-metallic pipes was proposed based on the experimental results of single-phase flow using dimension and regression analyses. The solutions of the anomalous phenomenon were proposed from the perspectives of the pipe diameter, contact-angle difference, and the compatibility between flexible composite pipe and JLHW105 oil according to the new formula. The surprising finding was that the surface wettability could control the frictional resistance by the critical contact angle(39.9°) obtained at the same Reynolds number. If 0° b θ≤ 39.9°, the frictional coefficient increased as the contact angle increased. In contrast, if 39.9° b θ b 180°,the frictional coefficient decreased with increasing contact angle. The influences of the pipe diameter and contactangle difference on the pressure drop difference of JLHW105 oil showed an inversely proportional relation. A series of materials and liquids were tested. The selection of pipe material for transporting a given fluid can be based on the contact angle, surface tension, and critical limit of the contact angle obtained. The research results are expected to provide some guidelines for the selection of the appropriate pipe material for a given set of fluids.     

大庆油田聚合物驱配注工艺技术

大庆油田采用聚合物驱油弥补水驱后期产量下降和提高采收率，并同步开展了聚合物配注工艺的研究与聚合物驱油试验。应用聚合物分散装置、熟化搅拌器和聚合物熟化储存合一配制工艺，实现聚合物干粉的大容量分散和快速搅拌溶解；通过大排量输送泵、母液过滤器、低黏度损失流量调节器、母液静态混合器等核心工艺设备，研发一管多站母液外输工艺、一泵多井注入等简化配注工艺，实现了聚合物母液低黏度损失与长距离多环节输送、注入，优化形成"集中配制、分散注入"的总体工艺流程。简化的聚合物驱地面工艺技术既保证了聚合物溶液低黏度损失高精度配注，又降低了地面工程投资和运行成本，技术上支撑了聚合物驱油技术的大规模工业化应用，并根据聚合物配注工艺技术的发展趋势，提出了相关建议。     

Short‐term effects in a reduced flow stretch: The case of the Antas River in South Brazil

The building of adduction channels (penstocks) that conduct water from reservoirs to turbines, which are located kilometres from the dam, is becoming common, optimizing the electricity generation in small dams. This design creates a river stretch with reduced discharge between the dam and the powerhouse. This study evaluates the short‐term impacts of the below‐dam decrease in river flow on fish assemblages. Samples were collected in the reduced flow stretch of the Castro Alves Hydropower Plant (Antas River, Rio Grande do Sul, Brazil) before the reservoir started operating (January 2008; mean discharge of 103.7 m³/s) and immediately after operation began (March 2008; mean discharge of 12.4 m³/s). Sampling was conducted in distinct habitats of the reduced flow stretch (slow waters—gillnets, sand beaches—seining nets, structured littoral—electrofishing, and fast waters—cast nets) with a strongly standardized effort. The attributes of the fish assemblages were not negatively affected by the flow reduction in any habitat sampled. However, distinct changes in the spatial structure were observed considering the different types of habitat predominantly used by the species, which represents an entire reorganization of the fish assemblages in the short term. It is fundamental that these short‐term aspects be considered in the licensing of hydropower plants in addition to the long‐term changes.     

基于光流法的固体内部声传播方向测量

目前采用光弹设备测量超声传播方向多为人眼主观观测,其误差较大,难以实现精确的定量测量。将Farneback光流法应用于光弹图像的处理,并根据帧与帧之间的光流图来计算光弹图像中的超声传播方向,可以捕捉图像中的动态声场。在实验中对不同传播方向的超声进行了测量,其绝对偏差度数最大值为2.85°,测量结果较为准确。因此,Farneback光流法可用于光弹图像中声波传播方向的判断,且具有快速、准确和直观等特点。