Copper foam-derived electrodes as efficient electrocatalysts for conventional and hybrid water electrolysis

Electrochemical water splitting has been demonstrated as a promising technology for the renewable generation of green hydrogen from water.Despite the extensive progress in materials science,one particular challenge for further development towards industrial application lies in the rational design and exploitation of efficient and cost-effective materials,especially oxygen evolution reaction(OER)electrocatalysts at the anode.In addition,attempts to replace the OER with other more oxidizable anode reactions are being evaluated as a groundbreaking strategy for generating hydrogen at lower potentials and reducing overall energy costs while producing valuable chemicals simultaneously.Compared with Fe/Co/Ni-based compounds,Cu-based materials have not received extensive research attention for electrode designs despite their high conductivity and abundant earth reserves.In this review,combining with the advantages of a three-dimensional network structure of metal foams,we summarize recent progress on Cu foam(CF)-derived materials as efficient electrocatalysts towards pure water electrolysis and hybrid water electrolysis.The advantages of CF and design strategies to enhance the electrocatalytic activity and operational durability are presented first.Catalyst design and fabrication strategies are then highlighted and the structure-activity relationship is also discussed.Finally,we propose challenges and perspectives on self-supported electrodes beyond CF-derived materials.

Hybrid water electrolysis:Replacing oxygen evolution reaction for energy-efficient hydrogen production and beyond

Renewable energy-driven hydrogen generation from water electrolysis has been widely recognized as a promising approach to utilize sustainable energy resources,reduce our dependence on legacy fossil fuels and alleviate net carbon dioxide emissions.However,conventional water electrolyzers suffer from the high overpotentials,mainly due to the sluggish kinetics of anodic oxygen evolution reaction(OER).This reaction also generates reactive oxygen species that could degrade the proton exchange membrane and oxygen that may mix with the cathodic hydrogen to form explosive gaseous mixtures.To address these issues,an innovative hybrid water electrolysis strategy which involves a certain alternative oxidation reaction to replace OER has been developed,and has led to a burgeoning area that sparks much research interest in finding available alternative reactions and their corresponding electrocatalysts.Herein,we summarize the alternative reactions into three groups:(1)the reagentsacrificing type that can generate H2 with an ultra-low potential while the substrates are oxidized to valueless products;(2)the pollutant-degrading type at which environmental pollutants are used as substrates;(3)the valueadded type that produces valuable products at the anode.Catalyst and electrolyzer designs for hybrid electrolysis are also briefly discussed,with an emphasis on the catalyst reconstruction phenomenon.Finally,the present challenges and perspectives are put forward.

Recent advances in hybrid water electrolysis for energy-saving hydrogen production

Electricity-driven water splitting to convert water into hydrogen(H_(2)has been widely regarded as an efficient approach for H_(2)production.Nevertheless,the energy conversion efficiency of it is greatly limited due to the disadvantage of the sluggish kinetic of oxidation evolution reaction(OER).To effectively address the issue,a novel concept of hybrid water electrolysis has been developed for energy–saving H_(2)production.This strategy aims to replace the sluggish kinetics of OER by utilizing thermodynamically favorable organics oxidation reaction to replace OER.Herein,recent advances in such water splitting system for boosting H_(2)evolution under low cell voltage are systematically summarized.Some notable progress of different organics oxidation reactions coupled with hydrogen evolution reaction(HER)are discussed in detail.To facilitate the development of hybrid water electrolysis,the major challenges and perspectives are also proposed.

Trans-umbilical endoscopic cholecystectomy with a water-jet hybrid-knife:A pilot animal study

AIM:To investigate the feasibility and safety of Natural orifice trans-umbilical endoscopic cholecystectomy with a water-jet hybrid-knife in a non-survival porcine model.METHODS:Pure natural orifice transluminal endoscopic surgery(NOTES) cholecystectomy was performed on three non-survival pigs,by transumbilical approach,using a water-jet hybrid-knife. Under general anesthesia,the following steps detailed the procedure:(1) incision of the umbilicus followed by the passage of a double-channel flexible endsocope through an overtube into the peritoneal cavity;(2) establishment of pneumoperitoneum;(3) abdominal exploration;(4)endoscopic cholecystectomy:dissection of the gallbladder performed using water jet equipment,ligation of the cystic artery and duct conducted using nylon loops;and(5) necropsy with macroscopic evaluation.RESULTS:Transumbilical endoscopic cholecystectomy was successfully completed in the first and third pig,with minor bleedings. The dissection times were 137and 42 min,respectively. The total operation times were 167 and 69 min,respectively. And the lengths of resected specimen were 6.5 and 6.1 cm,respectively.Instillation of the fluid into the gallbladder bed produced edematous,distended tissue making separation safe and easy. Reliable ligation using double nylon loops insured the safety of cutting between the loops.There were no intraoperative complications or hemodynamic instability. Uncontrolled introperative bleeding occurred in the second case,leading to the operation failure.CONCLUSION:Pure NOTES trans-umbilical cholecystectomy with a water-jet hybrid-knife appears to be feasible and safe. Further investigation of this technique with long-term follow-up in animals is needed to confirm the preliminary observation.

The Effect of Water Absorption on Mechanical Properties of Wood Flour/Wheat Husk Polypropylene Hybrid Composites

The main objectives of this research were to study the effect of water absorption on mechanical properties of hybrid fiber reinforcement for polypropylene composites. The poor resistance towards water absorption is one of the draw- backs of natural fibers. Hybrid filler-polypropylene composites are subjected to water immersion tests in order to study the effects of water absorption on the mechanical properties. Composites specimens containing 30 phr and 40 phr fiber weight were prepared by melt blending process. Water absorption tests were conducted by immersion specimens in distilled water at room temperature for different time durations (24, 48, 72, 96, 120, 144, 168, 192 hours). The tensile, flexural and impact properties were investigated before and after water absorption. The percentage of moisture uptake increased as the increasing order of the filler loading due to the high cellulose content. The phase morphology of wood flour/wheat husk polypropylene hybrid composites were investigated by SEM, the dynamic mechanical properties of the composite are analyzed by DMA & wheat, wood filler interaction are analyzed by FT-IR.

HYBRID FINITE ANALYTIC SOLUTIONS OF SHALLOW WATER CIRCULATION

The hybrid finite analytic(HFA) method is a kind of numerical scheme in rectangular element. In order to simulate the shallow circulation in irregular bathymetry by HFA scheme, the model in sigma coordinate system was obtained. The model has been tested against three cases: 1) Wind induced circulation; 2) Density driven circulation and 3) Seiche oscillation. The results obtained in the present study compare well with those obtained from the corresponding analytical solutions under idealized for the above three cases. The hybrid finite analytic method and the circulation model in sigma coordinate system can be used calculate the flow and water quality in estuaries and coastal waters.

Hybrid Model Testing Technique for Deep-Sea Platforms Based on Equivalent Water Depth Truncation

In this paper, an inner turret moored FPSO which works in the water of 320 m depth, is selected to study the socalled ＂passively-truncated ＋ numerical-simulation＂ type of hybrid model testing technique while the tnmcated water depth is 160 m and the model scale ）, = 80. During the investigation, the optimization design of the equivalent-depth truncated system is performed by using the similarity of the static characteristics between the truncated system and the full depth one as the objective function. According to the truncated system, the corresponding physical test model is made. By adopting the coupling time domain simulation method, the tnmcated system model test is numerically reconstructed to carefully verify the computer simulation software and to adjust the corresponding hydrodynamic parameters. Based on the above work, the numerical extrapolation to the full depth system is performed by using the verified computer software and the adjusted hydrodyrmmic parameters. The full depth system model test is then performed in the basin and the results are compared with those from the numerical extrapolation. At last, the implementation procedure and the key technique of the hybrid model testing of the deep-sea platforms are summarized and printed. Through the above investigations, some beneficial conclusions are presented.

绿色优质节水抗旱稻新组合‘旱优640'的选育及制繁种技术

‘旱优640‘是以沪旱5A为母本、旱恢1640为父本,由上海市农业生物基因中心选育而成的绿色、优质、节水、适应性广的抗旱新品种。2021年通过上海市审定(沪审稻2021009)。本文详细介绍了‘旱优640’的选育过程、特征特性、繁种与制种技术,为‘旱优640’的大面积推广应用提供参考。

超滤-纳滤双膜工艺深度净化天然雨水试验

随着人口数量增长与城市工业化进程的不断加快,对水资源的需求日益剧增。为了缓解水资源压力同时减轻城市排水系统的负担,开展了超滤-纳滤双膜工艺深度净化天然雨水的试验,探究了双膜工艺对天然雨水的水质净化效果。结果表明,超滤-纳滤双膜工艺可以有效降低雨水中污染物含量,对UV_(254)、总溶解性固体、总有机碳和电导率的平均去除率分别为87.5%、66.7%、32.0%和61.4%。双膜技术实现了对雨水中固体颗粒和溶解性有机物的高效去除,同时对荧光类有机物也显示出优异的截留效果。相比于常规的水处理工艺(混凝-沉淀-过滤工艺),双膜技术因具有出水水质优异、无二次污染、处理效率高等优势,在雨水的高效分离和资源化利用领域展现出较大的应用潜力。

玻璃纤维增强聚丙烯/尼龙混杂板材的制备与性能研究

玻璃纤维增强热塑性复合材料具有重复成型、高韧性、高耐久性、可设计、环境友好及可回收利用等优势。为解决由聚丙烯树脂粘度高与尼龙树脂吸水率高引起的复合材料成型工艺与耐久性问题,本项目采用模压工艺研发并制备了玻璃纤维增强聚丙烯/尼龙混杂复合材料板材,研究了混杂模式对于板材力学性能与热性能的影响规律与机理,比较分析了水分子在混杂复合材料内的扩散行为。研究发现,单层层间交替混杂模式板材具有最高的力学性能,拉伸、弯曲和剪切强度最大提升率为132.8%、127.4%和110.4%,归因于混杂板材中两种预浸带在层间粘结-挤压作用下协同受力,材料性能充分发挥;相比之下,五层预浸带层间交替混杂模式板材存在明显薄弱界面层,削弱了板材整体协同受力作用。此外,混杂板材由于聚丙烯树脂憎水性以及逐层交替混杂模式,延缓或阻止了水分子在尼龙树脂内部的吸收和扩散行为,导致混杂板材吸水率大幅下降,这对于提升尼龙树脂基复合材料的耐久性具有重要意义。

基于氢氧同位素的平原湖荡地表水与地下水转化研究

地表水与地下水间的相互转化以及量化地下水补给量是湖泊水循环研究的重要内容。本文采集了元荡湖区域湖水、地下水样品,测试了其氢氧稳定同位素组成和水化学组成,运用Piper三线图分析其水化学类型、通过钻孔实测的地下水埋深绘制元荡湖区域旱季(2022年12月)和雨季(2023年6月)的地下水水位等值线图,结合电导率(EC)和溶解性总固体(TDS)定性分析地表水-地下水之间的转化关系,利用同位素水量平衡方程、线性端元混合模型定量评价了湖水、地下水、河水和降水之间的转化量。结果表明,研究区湖水和地下水的水化学类型均为HCO_(3)^(-)·SO_(4)^(2-)·Ca^(2+)·Na^(+)·Mg^(2+),旱季和雨季湖水均受到地下水的补给,拟合得到的湖水旱季、雨季氢氧稳定同位素线性回归方程表明雨季斜率较小,蒸发更为强烈。湖水主要由河水、地下水和降水补给,其三者在旱季的补给比例分别为59%、26%和15%,在雨季的补给比例分别为23%、39%和38%。本文成果为元荡湖区域以及太湖流域的综合治理提供了科学依据。

永磁同步电机机壳串并联混合流道液冷分析

针对机壳串联流道水冷永磁同步电机散热冷却水压力损失过大的问题,提出一款新型机壳串并联混合流道,对某型号42 kW车用永磁同步电机冷却散热进行了计算,比较了机壳串并联混合流道与串联流道冷却电机最高温度与冷却水压力损失,分析了机壳串并联混合流道环形流道数量、槽深及冷却水流量对电机冷却散热影响。结果表明:电机以额定工况运行时,在相同对流换热面积及冷却液流量条件下,机壳串并联混合流道冷却水进出口压降比串联流道减小26 693 Pa,降低67%,而机壳串并联混合流道比串联流道冷却电机最高温度升高0.6℃,增大0.68%;机壳串并联混合流道环形流道数量增多或冷却水流量增大均能加快机壳串并联混合流道冷却永磁同步电机散热,但冷却水压力损失会有所增大;流道槽深增加可显著降低冷却水压力损失,但对电机最高温度变化影响较小。

水分对混合动力汽车发动机油摩擦磨损性能的影响

混合动力汽车的动力包括电机和发动机。电机的使用降低了发动机的使用频率,从而使发动机温度降低,导致混入发动机油中的水分不易蒸发出去。为考察水分对混合动力汽车发动机油摩擦磨损性能的影响,使用SRV5试验机评价了不同含水量混合动力汽车汽油机油的摩擦磨损性能,使用激光共聚焦显微镜检测了试验盘磨斑的宽度和磨损体积,使用扫描电子显微镜观察了试验盘磨斑表面的形貌。结果表明:少量水分对油品的摩擦磨损性能无不利影响;油对轴承钢的润湿性明显优于水,会优先于水吸附在轴承钢表面,在含有大量水时仍具有一定的抗磨损性能。

短期微流水处理对池塘养殖杂交鲌“先锋1号”肌肉品质的影响

以池塘养殖杂交鲌“先锋1号”为对象,采用短期微流水处理,研究处理时间(0、4、8和12d)对杂交鲌“先锋1号”色度、肌纤维直径、肌肉质构特性、常规营养成分、氨基酸和脂肪酸含量的影响,以评价短时间微流水处理对杂交鲌“先锋1号”品质的提升作用。结果显示,微流水条件下,8 d和12 d皮的黄度值(b^(*))显著升高,各实验组肌肉的红度值(a^(*))显著降低(P<0.05,下同)。处理8 d时,肌纤维密度、肌肉硬度、咀嚼性和弹性显著提升,分别较对照组提升了70.96%、92.04%、198.99%和35.71%。随着处理时间的延长,粗蛋白和粗脂肪含量显著降低,灰分在处理过程中无显著差异(P>0.05,下同);杂交鲌“先锋1号”在处理4d时的鲜味氨基酸总量(DAA)显著高于8d和12d;氨基酸总量(TAA)和必需氨基酸总量(EAA)变化不显著,各组必需氨基酸指数(EAAI)分别为77.33%、74.91%、76.56%和76.75%。第8天时,肌肉中顺-15-二十四碳一烯酸(C24:1)、花生三烯酸(C20:3n6)和花生四烯酸(C20:4n6)含量分别为6.85、41.05和53.84 mg/100 g显著高于其他各组,而α-亚麻酸含量,单不饱和脂肪酸总量和n-6多不饱和脂肪酸(n-6PUFAs)总量分别为48.05、1336.43和524.43 mg/100 g显著高于4 d和12 d。研究表明,短期微流水处理8 d时,在保证肌肉营养品质的同时,可有效改善其体色和肌肉颜色,增加肌肉口感,为池塘养殖淡水产品品质提升提供新的思路。

抗菌剂在水处理膜中的应用进展

随着城市工业化进程的加快,环境日益恶化,微生物、细菌滋长等水污染问题严重影响人类的生活及生命安全。在水处理过程中,抗菌膜可以将水中的污染物、细菌与水进行分离。由于污水中存在大量的细菌,可能会附着在膜上并快速繁殖,导致二次污染。基于此,综述了近年来抗菌剂在水处理膜中的应用进展,从无机抗菌剂、有机抗菌剂和天然抗菌剂等方面探讨了水处理膜的抗菌机理,并展望了水处理抗菌膜技术的发展趋势。

渔光互补光伏电站水域环境下桩基础选型与施工技术研究

首先阐释了渔光互补光伏电站的内涵、作用,其次从地质条件、地形地貌、桩基类型、桩基设计、环境影响评价5个方面归纳了桩基础选型的参考因素,并以阳新县A项目为例,介绍了A项目的桩基础选型,从施工准备、施工流程、施工质量控制等出发,最后探讨了A项目施工技术,并整理了A项目施工中的安全风险、环境风险控制措施。

PP&PE杂化材料用水性抗静电涂料的研制

以自制烯烃改性磺酸盐型水性聚氨酯为主体树脂,引入高Tg值水性氯化聚丙烯树脂作为改性树脂,通过添加复合导电颜填料和单壁碳纳米管,制备了PP&PE杂化材料用功能型水性抗静电涂料。该产品以水分为散介质,施工工艺简单,常温即可固化,是节能环保型产品;固化后形成的涂层在PP&PE杂化材料上附着力突出,机械强度高,具有持久、稳定的低电阻(≤105Ω)特性,可有效增加基材表面硬度和抗划伤能力,增强其耐候性,能够及时有效地消除材料表面的静电积累,防止静电火灾和静电爆炸的发生,保障生产经营安全。

无机-有机杂化硅环氧乳液制备及其在防腐涂料中的应用研究

采用自乳化法,将丙烯酸单体通过自由基接枝改性环氧的同时,引入无机-有机杂化硅,得到无机-有机杂化硅环氧乳液。研究了反应温度、乳化剂含量对于乳液性能的影响,结果显示反应温度在83℃,乳化剂质量分数为2.9%,无机-有机杂化硅质量分数为2%时,合成的无机-有机杂化硅环氧乳液具有良好的综合性能。此外,制得的防腐底漆、中间漆的各项技术指标超过标准要求,能满足各种应用需求。

基于混合滤波器的水炮打击目标轨迹预测方法

在智能水炮打击处于运动状态的目标船舶时,射流在空中运动所耗时间会导致打击脱靶问题。针对这种情况,提出一种基于混合滤波器的水炮打击目标轨迹预测方法。该方法首先采集目标跟踪设备的轨迹数据,然后使用轨迹数据训练混合滤波器模型,最后使用模型实时预测目标轨迹。实验结果表明,在搭建的智能水炮实验环境中,持续预测目标未来0~2s的轨迹,均方误差在0.3025~1.4832之间,预测效果良好,在实际应用中,该方法有效地解决了智能水炮打击运动目标时的脱靶问题。