深圳抽水蓄能电站引水系统灌浆质量控制与分析

抽水蓄能电站引水系统灌浆质量控制,决定了水道系统渗水量的大小,关系到电站长期运行的经济指标及水道安全。详细介绍了深圳抽水蓄能电站灌浆参数的设计和灌浆中采取的管理措施与技术措施,分析了灌浆检测成果。电站投入运行以来,引水系统结构稳定,无渗漏。通过总结深圳抽水蓄能电站灌浆过程,对水道引水系统灌浆质量控制提出了几点建议,可供类似工程借鉴。     

城市排水管网风险评估研究

总结了常见的城市排水管网风险评估的方法及软件,对污水管网的气体爆炸风险、雨水管网的内涝风险、综合风险这三类风险评估的文献进行了归纳整理,并对未来的研究重点及趋势做出了预测。     

Additive manufacturing of bipolar plates for hydrogen production in proton exchange membrane water electrolysis cells

Water electrolysis is a process that can produce hydrogen in a clean way when renewable energy sources are used. This allows managing large renewable surpluses and transferring this energy to other sectors, such as industry or transport. Among the electrolytic technologies to produce hydrogen, proton exchange membrane (PEM) electrolysis is a promising alternative. One of the main components of PEM electrolysis cells are the bipolar plates, which are machined with a series of flow distribution channels, largely responsible for their performance and durability. In this work, AISI 316L stainless steel bipolar plates have been built by additive manufacturing (AM), using laser powder bed fusion (PBF-L) technology. These bipolar plates were subjected to ex-situ corrosion tests and assembled in an electrolysis cell to evaluate the polarization curve. Furthermore, the obtained results were compared with bipolar plates manufactured by conventional machining processes (MEC). The obtained experimental results are very similar for both manufacturing methods. This demonstrates the viability of the PBF-L technology to produce metal bipolar plates for PEM electrolyzers and opens the possibilities to design new and more complex flow distribution channels and to test these designs in initial phases before scaling them to larger surfaces.     

A highly active composite electrocatalyst Ni–Fe–P–Nb2O5/NF for overall water splitting

This work demonstrates a facile Nb₂O₅-decorated electrocatalyst to prepare cost-effective Ni–Fe–P–Nb₂O₅/NF and compared HER & OER performance in alkaline media. The prepared electrocatalyst presented an outstanding electrocatalytic performance towards hydrogen evolution reaction, which required a quite low overpotential of 39.05 mV at the current density of ?10 mA cm^?2 in 1 M KOH electrolyte. Moreover, the Ni–Fe–P–Nb₂O₅/NF catalyst also has excellent oxygen evolution efficiency, which needs only 322 mV to reach the current density of 50 mA cm^?2. Furthermore, its electrocatalytic performance towards overall water splitting worked as both cathode and anode achieved a quite low potential of 1.56 V (10 mA cm^?2).     

Promoted electrocatalytic hydrogen evolution performance by constructing Ni12P5–Ni2P heterointerfaces

Transition metal phosphides (TMPs) have been considered as cheap alternatives of precious metal platinum for electrochemical hydrogen evolution reaction (HER). In the past decades, many reports have indicated that the engineering of heterointerfaces between different components could efficiently enhance the activity of HER catalysts. Here, we report a facile method to construct Ni₁₂P₅–Ni₂P heterostructure by using a low temperature phosphorization strategy. The obtained Ni₁₂P₅–Ni₂P heterostructure shows high activity toward HER with an overpotential value of 166 mV at 10 mA cm^?2 and a Tafel slope of 60 mV dec^?1 in 0.5 M H₂SO₄. Compared with pure Ni₂P and Ni₁₂P₅, the Ni₁₂P₅–Ni₂P heterostructure has more active sites and faster HER kinetics due to the presence of the interfaces between Ni₁₂P₅ and Ni₂P. Furthermore, we used the obtained Ni₁₂P₅–Ni₂P as cathodic catalyst and IrO₂/Ti as anodic material to set up a proton exchange membrane (PEM) electrolyzer which shows good stability after 120 h continuous constant current electrolysis at 200 mA cm^?2. This work demonstrates the positive effect of heterostructure for HER catalysts and provides a feasible strategy for constructing earth-abundant electrocatalysts.     

水产品及养殖水中丁香酚类化合物风险研究

目的 检测水产品及养殖水中丁香酚类化合物。方法 应用食品补充检验方法BJS 201908《水产品及水中丁香酚类化合物的测定》，以海水鱼、淡水鱼、海水虾、淡水虾及养殖水作为基质，测定6种丁香酚类化合物的含量。结果 通过对实际样品测定后发现，在水产品中检出了丁香酚类化合物，主要为丁香酚，检出率为28.9%，其中海水鱼相对突出。结论 本研究为丁香酚作为渔用麻醉剂提供了方法论，为丁香酚类化合物在水产运输的合理使用提供理论依据。     

Invited review: Freedom from thirst—Do dairy cows and calves have sufficient access to drinking water?

The importance of drinking water for production and animal welfare is widely recognized, but surveys and animal welfare assessment schemes suggest that many dairy calves and dairy cows do not have sufficient access. Limit milk-fed calves drink more water than calves fed milk ad libitum, but ad libitum milk-fed calves also require access to drinking water, as milk does not meet the animal's requirement for water. At hot ambient temperatures and when calves are sick, access to water is especially important and should be provided at all times. Many young calves do not have access to water throughout 24 h, and whether healthy young calves require free access to water at all times, or from which age, is not clear and requires further study. Dairy cow free water intake (FWI) is largely determined by milk yield, and high-yielding dairy cows may drink up 100 L of water per day. Dry matter, crude protein, and salt content of feed, as well as ambient temperature, have considerable effects on dairy cow water intake. Deprivation of water affects meal patterning for the cow, as well as increased subsequent rate of drinking and compensatory water intake. Although dairy cow ad libitum water intake may exceed the water provision necessary to maintain production, offering water for ad libitum intake may be necessary to safe guard animal welfare. Cattle are suction drinkers that prefer to drink from large open water surfaces, and Holstein dairy cows can drink at a rate of up to 24 L/min. Research on the effect of design and placement of water troughs for indoor-housed dairy cows on their drinking behavior and water intake is limited. Access to a water source at pasture increases the time cows spend there, and access to shade reduces water requirements during periods of warm weather. In both indoor and pastured cattle, there is a lack of knowledge about the effect of stocking of water troughs on competition, drinking behavior, and intake in dairy cows. Studies on the effect of available water trough length and placement, and of the number of cows being able to drink from the same trough of a given dimension, are needed to evaluate current recommendations.     

现代市政道路给排水管道工程的设计与施工探讨

市政道路给排水管道工程设计与施工是一个综合性的过程,要考虑各个方面的影响因素,其工程质量关系着城市运行的稳定性,具有非同寻常的作用。在市政道路给排水工程施工中,需要涉及到多个工艺环节,要合理调控各个环节的连接关系,保证工程的有序施工,严格管控工程质量。     

Heterogeneous Bimetallic Mo-NiPx/NiSy as a Highly Efficient Electrocatalyst for Robust Overall Water Splitting

Highly efficient electrocatalysts composed of earth-abundant elements are desired for water-splitting to produce clean and renewable chemical fuel. Herein, a heteroatomic-doped multi-phase Mo-doped nickel phosphide/nickel sulfide (Mo-NiP_x/NiS_y) nanowire electrocatalyst is designed by a successive phosphorization and sulfuration method for boosting overall water splitting (both oxygen and hydrogen evolution reactions (HER)) in alkaline solution. As expected, the Mo-NiP_x/NiS_y electrode possesses low overpotentials both at low and high current densities in HER, while the Mo-NiP_x/NiS_y heterostructure exhibits high active performance with ultra-low overpotentials of 137, 182, and 250 mV at the current density of 10, 100, and 400 mA cm⁻² in 1 m KOH solution, respectively, in oxygen evolution reaction. In particular, the as-prepared Mo-NiP_x/NiS_y electrodes exhibit remarkable full water splitting performance at both low and high current densities of 10, 100, and 400 mA cm⁻² with 1.42, 1.70, and 2.36 V, respectively, which is comparable to commercial electrolysis.     

Skeletal Muscle Health and Cognitive Function: A Narrative Review

Sarcopenia is the loss of skeletal muscle mass and function with advancing age. It involves both complex genetic and modifiable risk factors, such as lack of exercise, malnutrition and reduced neurological drive. Cognitive decline refers to diminished or impaired mental and/or intellectual functioning. Contracting skeletal muscle is a major source of neurotrophic factors, including brain-derived neurotrophic factor, which regulate synapses in the brain. Furthermore, skeletal muscle activity has important immune and redox effects that modify brain function and reduce muscle catabolism. The identification of common risk factors and underlying mechanisms for sarcopenia and cognition may allow the development of targeted interventions that slow or reverse sarcopenia and also certain forms of cognitive decline. However, the links between cognition and skeletal muscle have not been elucidated fully. This review provides a critical appraisal of the literature on the relationship between skeletal muscle health and cognition. The literature suggests that sarcopenia and cognitive decline share pathophysiological pathways. Ageing plays a role in both skeletal muscle deterioration and cognitive decline. Furthermore, lifestyle risk factors, such as physical inactivity, poor diet and smoking, are common to both disorders, so their potential role in the muscle–brain relationship warrants investigation.