Accelerate the alkaline hydrogen evolution reaction of the heterostructural Ni2P@Ni(OH)2/NF by dispersing a trifle of Ru on the surface

Electrocatalytic water splitting for hydrogen production plays a vital role in the development of new energy field, but there is still a lack of low-content precious metal or cost-effective non-noble metal catalysts for the hydrogen evolution reaction (HER). Therefore, how to develop the catalysts with a smaller amount of precious metal to achieve higher performance is still a major challenge. Herein, we have fabricated Ru–Ni₂P@Ni(OH)₂/NF-2 heterostructure by phosphating Ni(OH)₂/NF and then anchoring Ru on the surface through wet chemical strategy. Benefiting from its optimal ΔG_H1 and synergistic effect, this Ru–Ni₂P@Ni(OH)₂/NF-2 catalyst shows superior electrocatalytic HER kinetics in alkaline electrolyte. A small overpotential of 31 mV is needed for this electrocatalyst to obtain the current densities of 10 mA cm^?2 with remarkable durability over 24 h. This work provides a new strategy for the preparation of effective HER electrocatalyst with a low precious metal content.     

基于寒地特征的沈北蒲河生态城市规划思考

寒地城市因特殊的气候特征而给城镇居民生产、生活带来许多不便,极大地制约着区域协调可持续发展。针对寒地城市规划实践长期缺乏基础理论指导的现状,本文试图从地域功能综合体的视角引入生态城市理念——生态城市是一个基于"经济—社会—自然环境"的复合生态系统,一个"功能合理、结构明确、形态俱佳的有机协调统一体";并据此从复合生态系统视角分析寒地城市规划的内容组分,从有机协调统一体视角组织寒地城市规划功能结构和空间布局,以期为我国寒地城市规划实践提供一个系统的理论指导框架。最后以沈北蒲河新城为例,进行实证分析。     

安川变频器在扶梯中的应用浅析

随着经济的发展,人们对生活品质要求的逐渐提高,各种大型购物中心、地铁线路的开通、机场、客运场所的设施不断完善,自动扶梯的需求越来越大。而变频器作为具有节能、调速等性能优势的现代化产品,在扶梯行业被广泛应用。     

小型枝桠削片机飞刀结构改进设计

针对小型枝桠削片机匕刀结构存在的问题，对飞刀结构进行改进。并从原理上对改进设计进行了分析。     

静电拣梗机振动筛的设计与分析

静电拣梗机振动筛,是CTC红碎茶生产的关键设备之一.为了确定振动筛筛框的应力分布规律,保证筛框具有足够的强度, 建立了筛框的计算有限元模型.通过ANSYS软件对筛框进行了模态分析,并计算出筛框前4阶固有频率和振动模态.分析结果表明,振动筛筛框整体固有频率较高,远离正常工作频率,振动筛筛框的刚性比较好.     

水解法石墨烯掺杂TiO_2的制备及表征

以氧化石墨烯和工业钛液为原料,直接水解制备二氧化钛氧化石墨烯复合材料。用扫描电镜和原子力显微镜对复合材料结构和形貌进行研究,材料基团结构用红外光谱进行分析,光吸收特性用紫外可见分光光度计进行分析。结果发现:随着氧化石墨烯用量的增加,复合材料的带隙逐渐减小,有利于可见光的吸收。在一定添加范围内,氧化石墨烯对复合材料的光催化效果有促进作用。     

Snowvision: Segmenting,Identifying, and Discovering Stamped Curve Patterns from Fragments of Pottery

In southeastern North America, Indigenous potters and woodworkers carved complex, primarily abstract, designs into wooden pottery paddles, which were subsequently used to thin the walls of hand-built, clay vessels. Original paddle designs carry rich historical and cultural information, but pottery paddles from ancient times have not survived. Archaeologists have studied design fragments stamped on sherds to reconstruct complete or nearly complete designs, which is extremely laborious and time-consuming. In Snowvision, we aim to develop computer vision methods to assist archaeologists to accomplish this goal more efficiently and effectively. For this purpose, we identify and study three computer vision tasks: (1) extracting curve structures stamped on pottery sherds; (2) matching sherds to known designs; (3) clustering sherds with unknown designs. Due to the noisy, highly fragmented, composite-curve patterns, each task poses unique challenges to existing methods. To solve them, we propose (1) a weakly-supervised CNN-based curve structure segmentation method that takes only curve skeleton labels to predict full curve masks; (2) a patch-based curve pattern matching method to address the problem of partial matching in terms of noisy binary images; (3) a curve pattern clustering method consisting of pairwise curve matching, graph partitioning and sherd stitching. We evaluate the proposed methods on a set of collected sherds and extensive experimental results show the effectiveness of the proposed algorithms.

     

金霉素在鸡体内的药代动力学研究

本文用单剂量静脉注射的方法,研究了饲用金霉素在鸡体内的血药浓度变化,结果表明:金霉素在鸡体内的代谢迅速,其半衰期为1.1h,远小于其它四环素类抗生素,因而不适合全身性用药,而适于局部及消化道给药。     

“乌叶”与“兰竹”荔枝转色期果肉的差异蛋白分析

为探索转色期荔枝(Litchi chinensis Sonn.)品质形成过程中蛋白质的变化,应用蛋白质组学技术分析"乌叶"和"兰竹"荔枝品种转色期的差异蛋白质,共发现37个2倍以上的差异表达蛋白,32个差异蛋白被成功鉴定。这些蛋白参与了糖类和能量代谢(21.9%)、抗性胁迫(9.4%)、蛋白质代谢(15.6%)、细胞结构形成(12.5%)、次级代谢(12.5%)、发育调控(12.5%)和未知功能途径(15.6%)等代谢活动。与"兰竹"荔枝相比,"乌叶"荔枝中与糖酵解途径和能量代谢相关蛋白均下调表达,说明在转色期,"乌叶"荔枝中糖类物质降解速率较慢,有利于糖分的积累,形成高糖的品质。同时,"乌叶"荔枝中与细胞结构形成和抗性相关蛋白的上调表达,这有利于"乌叶"荔枝形成果肉质地密集、耐贮藏的良好品质。     

ATRP法制备磁性高分子微球及表征

通过化学共沉淀法制备了Fe3O4纳米磁性粒子作为内核,在其表面枝节一层引发剂,引发苯乙烯和丙烯酸的原子转移自由基聚合(ATRP)反应。通过SEM,TEM,IR,化学滴定法,表征,制备得到了粒径分布在40～50纳米,磁饱和强度为47.105emu/g,表面羧基含量在0.742mmol/g的磁性高分子复合微球。