Preparation,electronic structure and optical properties of CoxLaMg1−xAl11O19 microcrystals

Journal of Materials Science: Materials in Electronics - Co-doped LaMgAl11O19 microcrystals were synthesized by a facile sol–gel method. The as-synthesized microcrystals were near hexagonal...     

微波干燥软锰矿机理研究

采用微波加热法对软锰矿进行了深度干燥,考察了微波功率、物料质量、物料原始含水率、物料粒径等对其干燥效果的影响。结果表明物料在微波干燥180 s时达到最大脱水速率,且采用微波干燥在800 s时间内可将物料脱水至3.83%;原料质量一定时,随着微波功率的增大,有利于提高物料的脱水速率;微波功率一定时,在一定范围内增大物料质量和含水率,脱水速率就越快,干燥效果越好;物料粒径并非越小越好,反而大一些粒径的物料有助于物料加速脱水过程。     

光解水制氢催化剂的研究进展

面对人类对能源的需求持续增长以及化石能源的日益枯竭和其带来的环境污染问题,开发太阳能对于解决能源问题具有非常重要的意义。利用太阳能分解水制氢是一种将太阳能转换为氢能的有效方式。根据近年来国内外太阳能分解水制氢催化剂的研究现状,分别对半导体光催化剂和金属配合物光催化剂进行综述,并且从可持续发展和实际应用的角度出发,针对各自的优缺点,提出今后应该开发具有高效且成本低廉的非贵金属配合物光催化剂,或尝试与半导体光催化剂结合应用,提高制氢效率。     

Selection of Reliable Reference Genes for Gene Expression Studies of a Promising Oilseed Crop,Plukenetia volubilis,by Real-Time Quantitative PCR

Real-time quantitative PCR (RT-qPCR) is a reliable and widely used method for gene expression analysis. The accuracy of the determination of a target gene expression level by RT-qPCR demands the use of appropriate reference genes to normalize the mRNA levels among different samples. However, suitable reference genes for RT-qPCR have not been identified in Sacha inchi (Plukenetia volubilis), a promising oilseed crop known for its polyunsaturated fatty acid (PUFA)-rich seeds. In this study, using RT-qPCR, twelve candidate reference genes were examined in seedlings and adult plants, during flower and seed development and for the entire growth cycle of Sacha inchi. Four statistical algorithms (delta cycle threshold (ΔC_t), BestKeeper, geNorm, and NormFinder) were used to assess the expression stabilities of the candidate genes. The results showed that ubiquitin-conjugating enzyme (UCE), actin (ACT) and phospholipase A22 (PLA) were the most stable genes in Sacha inchi seedlings. For roots, stems, leaves, flowers, and seeds from adult plants, 30S ribosomal protein S13 (RPS13), cyclophilin (CYC) and elongation factor-1alpha (EF1α) were recommended as reference genes for RT-qPCR. During the development of reproductive organs, PLA, ACT and UCE were the optimal reference genes for flower development, whereas UCE, RPS13 and RNA polymerase II subunit (RPII) were optimal for seed development. Considering the entire growth cycle of Sacha inchi, UCE, ACT and EF1α were sufficient for the purpose of normalization. Our results provide useful guidelines for the selection of reliable reference genes for the normalization of RT-qPCR data for seedlings and adult plants, for reproductive organs, and for the entire growth cycle of Sacha inchi.     

智能手机蓝牙抄表设计方案

目前,在我国的电力、燃气、热力、自来水行业,大部分仍然采用无线远程集抄和手持抄表机的人工抄表模式。随着智能手机的普及,手机的功能和质量已经远远强于一般的数据采集手持设备。使用手机抄表软件可以轻松实现日常数据采集抄录工作。并可以使用手机的网络实现数据的及时上传下载。本文提供一种用于热量表的智能手机蓝牙抄表的抄收方法,该方法实现使用一部普通的android智能手机实现对热量表的抄读和设置。由于采取通用的智能手机平台,不依赖硬件设备,不需要定制产品,只需要额外加一个蓝牙转串口模块、采用相同的手机操作系统程序代码就可以通用,智能手机平台在编程工具方面都具有很好的扩展性,本方法在功能上扩展性强;智能手机平台在通信通道上有较强的延伸性,能够依照本方法搭建很好的解决方案,进行数据通信等。     

城市防灾避险功能的空间差异性评价——以深圳市经济特区为例

防灾避险功能评价是城市灾害管理及城市规划的重要内容之一,在系统梳理相关研究进展的基础上,采用了一种基于GIS空间直观表征的城市防灾避险功能评价方法,并针对深圳市经济特区内4类基础设施的防灾避险功能进行了综合评价。结果表明:研究区防灾避险功能由北向南逐渐降低,防灾避险功能辐射总面积为38322.09hm2,占研究区总面积的98%;但仍有2%的区域处于服务盲区,主要分布在南山区和福田区,少量分布在盐田区。     

Template‐free synthesis of novel hollow carbon nanospheres with dual active sites as catalyst for fuel cell cathode to improve oxygen reduction reaction performances

A new template‐free controlled method is reported herein to prepare the novel hollow carbon nanospheres with dual active sites of FeN₄ and FeC₃ by in situ growth reaction on graphene nanosheets, labeled as HCN‐FNFCG. As‐prepared HCN‐FNFCG nanomaterials possess hierarchically porous FeN₄/FeC₃ shells with structures of microporous, mesoporous, and macroporous properties. Moreover, the hierarchically porous HCN‐FNFCG nanomaterials with dual active sites of FeN₄ and FeC₃ have not been reported before. The HCN‐FNFCG nanomaterials, as oxygen reduction reaction (ORR) catalysts, are first studied systematically toward cathodic ORR of fuel cell. The measurements have illustrated that HCN‐FNFCG‐650 has the best ORR performances among these HCN‐FNFCG nanomaterials studied. The onset potential of HCN‐FNFCG‐650 has reached 1.095 V in alkaline electrolyte, and its maximum current density is 6.48 mA cm^?2. Additionally, the HCN‐FNFCG‐650 has also displayed small electrochemical impedance, its Tafel‐slope value is 44.25 mV dec^?1, much lower than that of the 20% Pt/C (69.57 mV dec^?1). And its value of current density is still maintained 92.83% of the initial value after 9000‐second continuous tests. High tolerance against methanol crossover is also exhibited for HCN‐FNFCG‐650. This novel method of template‐free synthesis can provide a promising strategy for preparing hollow nanospheres with hierarchically porous shells. And it can be used to design ORR electrocatalysts, electrode materials, or other applications.