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排序方式: 共有10000条查询结果,搜索用时 15 毫秒
1.
Sun  Kaian  Zhao  Lei  Zeng  Lingyou  Liu  Shoujie  Zhu  Houyu  Li  Yanpeng  Chen  Zheng  Zhuang  Zewen  Li  Zhaoling  Liu  Zhi  Cao  Dongwei  Zhao  Jinchong  Liu  Yunqi  Pan  Yuan  Chen  Chen 《Nano Research》2020,13(11):3068-3074

Large scale synthesis of high-efficiency bifunctional electrocatalyst based on cost-effective and earth-abundant transition metal for overall water splitting in the alkaline environment is indispensable for renewable energy conversion. In this regard, meticulous design of active sites and probing their catalytic mechanism on both cathode and anode with different reaction environment at molecular-scale are vitally necessary. Herein, a coordination environment inheriting strategy is presented for designing low-coordination Ni2+ octahedra (L-Ni-8) atomic interface at a high concentration (4.6 at.%). Advanced spectroscopic techniques and theoretical calculations reveal that the self-matching electron delocalization and localization state at L-Ni-8 atomic interface enable an ideal reaction environment at both cathode and anode. To improve the efficiency of using the self-modification reaction environment at L-Ni-8, all of the structural features, including high atom economy, mass transfer, and electron transfer, are integrated together from atomic-scale to macro-scale. At high current density of 500 mA/cm2, the samples synthesized at gram-scale can deliver low hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) overpotentials of 262 and 348 mV, respectively.

  相似文献   
2.
To design a clinically translatable nanomedicine for photodynamic theranostics, the ingredients should be carefully considered. A high content of nanocarriers may cause extra toxicity in metabolism, and multiple theranostic agents would complicate the preparation process. These issues would be of less concern if the nanocarrier itself has most of the theranostic functions. In this work, a poly(ethylene glycol)‐boron dipyrromethene amphiphile (PEG‐F54‐BODIPY) with 54 fluorine‐19 (19F) is synthesized and employed to emulsify perfluorohexane (PFH) into a theranostic nanoemulsion (PFH@PEG‐F54‐BODIPY). The as‐prepared PFH@PEG‐F54‐BODIPY can perform architecture‐dependent fluorescence/photoacoustic/19F magnetic resonance multimodal imaging, providing more information about the in vivo structure evolution of nanomedicine. Importantly, this nanoemulsion significantly enhances the therapeutic effect of BODIPY through both the high oxygen dissolving capability and less self‐quenching of BODIPY molecules. More interestingly, PFH@PEG‐F54‐BODIPY shows high level of tumor accumulation and long tumor retention time, allowing a repeated light irradiation after a single‐dose intravenous injection. The “all‐in‐one” photodynamic theranostic nanoemulsion has simple composition, remarkable theranostic efficacy, and novel treatment pattern, and thus presents an intriguing avenue to developing clinically translatable theranostic agents.  相似文献   
3.
ABSTRACT

Here, a novel cryogenic rolling plus intercritical annealing process was applied to a transformation-induced plasticity (TRIP) steel with a low chemical composition of carbon and manganese. Compared with traditional cold rolling, obvious grain refinement was observed, due to a high amount of dislocations retained. In addition, austenite volume fraction was increased, because of a unique nucleation mechanism. Subjected to cryogenic rolling, strength and ductility were increased, due to the enhanced austenite stability, which provided continuous and active TRIP effect. Consequently, tensile strength was increased to 1030?MPa, and elongation was increased to 38.2%. Thus, a great mechanical combination was obtained in a steel with a relatively low chemical composition with carbon and manganese, only by cryogenic rolling process.  相似文献   
4.
Xi  Jufang  Zhang  Liyun  Zheng  Wenting  Zeng  Qingle  He  Yi  He  Ze  Chen  Jingyu 《Journal of Materials Science》2021,56(32):18061-18077

Highly efficient adsorbents, which can effectively remove both metal ions and dyes from wastewater with robust stability, are strongly required for the remediation of current polluted aqueous system, but still a challenge to be realized. Herein, a new adsorbent has been designed to solve this problem by anchoring diethylene triamine pentaacetic acid (DTPA) grafted polyethyleneimine (PEI) onto carboxylated GO (GOC-g-PD). Given the amino and carboxyl active groups from PEI and GOC/DTPA, our GOC-g-PD displays good adsorption capacity against not only inorganic metal ions (Cu2+ and Pb2+) but also organic dye (methylene blue: MB). The maximum adsorption capacity of GOC-g-PD for Cu2+, Pb2+ and MB reached 309.60 mg·g?1, 316.17 mg·g?1 and 262.10 mg·g?1, respectively. Furthermore, our GOC-g-PD also exhibits good cycling stability and chemical stability against wide pH values. These outstanding properties revealed our GOC-g-PD held great potential in purifying the sewage discharged from industries.

Graphical abstract
  相似文献   
5.
王雅刚  白林  苏运河 《玻璃》2006,33(2):28-30
分析总结了几种常见配合料加水系统及其特点,并结合生产实际提出了不同系统的利弊和使用要点.  相似文献   
6.
介绍了槽波技术的原理及在东北地区几个矿的应用情况。  相似文献   
7.
魏学琳 《山西煤炭》2003,23(1):23-24,33
对22305工作面煤层厚度、结构、煤层顶底板地质构造、陷落柱、水文地质等进行了单项和综合评价,为更好地发挥综采优势提供了条件。  相似文献   
8.
在煤灰成分分析检测项目中有一些通常采用光电比色法进行检验.为了提高数据处理的准确度,采用一元线性回归方程对数据进行数理统计的方法,建立简单的数学模型,可快速、准确地获得计算结果.  相似文献   
9.
王琳 《煤矿安全》2011,42(2):42-44
根据矿井水文地质特征和突水原因,对突水通道和突水水源进行分析,采用引流式和压入式结合、井上下结合注浆堵水方法以及"夹层"注浆堵水技术,实现了快速封堵构造破碎带高压大流量突水。  相似文献   
10.
三峡机场灯光带滑坡,属典型的人工加载“后推式”碎石土滑坡类型。该滑坡治理前,稳定系数仅1.07,处于极限平衡状态,不仅严重阻碍机场灯光带导航系统的建设,且危及相距仅200m的汉宜高等级公路。该滑坡通过工程治理,达到了预期目的,收到了良好的社会和经济效益。  相似文献   
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