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991.
Alumina‐Supported CoFe Alloy Catalysts Derived from Layered‐Double‐Hydroxide Nanosheets for Efficient Photothermal CO2 Hydrogenation to Hydrocarbons 下载免费PDF全文
Guangbo Chen Rui Gao Yufei Zhao Zhenhua Li Geoffrey I. N. Waterhouse Run Shi Jiaqing Zhao Mengtao Zhang Lu Shang Guiyang Sheng Xiangping Zhang Xiaodong Wen Li‐Zhu Wu Chen‐Ho Tung Tierui Zhang 《Advanced materials (Deerfield Beach, Fla.)》2018,30(3)
A series of novel CoFe‐based catalysts are successfully fabricated by hydrogen reduction of CoFeAl layered‐double‐hydroxide (LDH) nanosheets at 300–700 °C. The chemical composition and morphology of the reaction products (denoted herein as CoFe‐x) are highly dependent on the reduction temperature (x). CO2 hydrogenation experiments are conducted on the CoFe‐x catalysts under UV–vis excitation. With increasing LDH‐nanosheet reduction temperature, the CoFe‐x catalysts show a progressive selectivity shift from CO to CH4, and eventually to high‐value hydrocarbons (C2+). CoFe‐650 shows remarkable selectivity toward hydrocarbons (60% CH4, 35% C2+). X‐ray absorption fine structure, high‐resolution transmission electron microscopy, Mössbauer spectroscopy, and density functional theory calculations demonstrate that alumina‐supported CoFe‐alloy nanoparticles are responsible for the high selectivity of CoFe‐650 for C2+ hydrocarbons, also allowing exploitation of photothermal effects. This study demonstrates a vibrant new catalyst platform for harnessing clean, abundant solar‐energy to produce valuable chemicals and fuels from CO2. 相似文献
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Fluorescent Imaging‐Guided Chemotherapy‐and‐Photodynamic Dual Therapy with Nanoscale Porphyrin Metal–Organic Framework 下载免费PDF全文
Wei Liu Yong‐Mei Wang Yu‐Hao Li Shi‐Jiao Cai Xue‐Bo Yin Xi‐Wen He Yu‐Kui Zhang 《Small (Weinheim an der Bergstrasse, Germany)》2017,13(17)
Imaging‐guided therapy systems (IGTSs) are revolutionary techniques used in cancer treatment due to their safety and efficiency. IGTSs should have tunable compositions for bioimaging, a suitable size and shape for biotransfer, sufficient channels and/or pores for drug loading, and intrinsic biocompatibility. Here, a biocompatible nanoscale zirconium‐porphyrin metal–organic framework (NPMOF)‐based IGTS that is prepared using a microemulsion strategy and carefully tuned reaction conditions is reported. A high content of porphyrin (59.8%) allows the achievement of efficient fluorescent imaging and photodynamic therapy (PDT). The 1D channel of the Kagome topology of NPMOFs provides a 109% doxorubicin loading and pH‐response smart release for chemotherapy. The fluorescence guiding of the chemotherapy‐and‐PDT dual system is confirmed by the concentration of NPMOFs at cancer sites after irradiation with a laser and doxorubicin release, while low toxicity is observed in normal tissues. NPMOFs are established as a promising platform for the early diagnosis of cancer and initial therapy. 相似文献
995.
多层数据库应用系统与传统数据库应用系统相比,具有提高代码的可重用性、提高系统安全性、便于模块管理等优越性,是开发信息系统的理想模式。这里结合具体的软件开发工具 C Builder,以开发多层数据库应用系统为对象,阐明了多层数据库应用系统的三层结构原理及数据库通讯机制,并给出了一个具体应用实例,验证了运用COM/DCOM 组件开发多层数据库应用系统的理论方法的正确性。 相似文献
996.
The microstructure of nano-SiC enhancing friction stir spot welding (FSSW) joint with dwell time of 3?s was characterised by an onion ring structure which consisted of alternate SiC-free zones and SiC-rich zones where SiC particles refined the grains. However, onion ring structure disappeared and SiC particles dispersed homogeneously when dwell time was 5?s. The microhardness of stir zone (SZ) and tensile shear load of SiC enhancing FSSW joint were higher than those of conventional FSSW joints. After heat treatment at 200°C for an hour, grains of the SZ grew substantially and coursed reduction in mechanical properties of joints, while grain size of SZ and tensile shear load of SiC enhancing joint was invariant but the microhardness of SZ increased. 相似文献
997.
在克服著名电子发票服务IBS协议缺陷的基础上,提出了一个新的电子发票服务协议。同时,采用新的基于扩展Kailar逻辑的分析方法对新协议进行了公平性形式化分析与修改,最终得到一个可以工作在不可靠信道上的公平电子发票服务协议。 相似文献
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Jungang He Jie Chen Yan Yu Ling Zhang Guangzu Zhang Shenglin Jiang Wen Liu Haisheng Song Jiang Tang 《Journal of Materials Science: Materials in Electronics》2014,25(3):1499-1504
In the present report, cadmium sulfide (CdS) colloidal quantum dots (CQDs) with average diameter of 6 nm were synthesized by using oleylamine as ligand and solvent. The insulating oleylamine ligands form barriers around the CdS CQDs to decrease carrier mobility. In order to remove the ligands and improve the photoelectrical properties of the closed-packed film, ethanedithiol, mercaptopropionic acid and cetyltrimethylammonium bromide (CTAB) were applied for solid state ligand exchange. CTAB treated film had the fastest 3 dB bandwidth of 144.7 Hz and yielded the highest detectivity of 1.37 × 108 Jones. The excellent properties of ligand passivation have important application in nanocrystals based electronic and optoelectronic devices. 相似文献