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91.
92.
Wenwen Zhao Kuibao Zhang Weiwei Li Baozhu Luo Haibin Zhang Kai Xu 《Ceramics International》2019,45(9):11717-11722
In this study, transparent LaErZr2O7 ceramic with high excess La and Er contents (nominally La1.28Er1.28Zr2O7.84) was successfully prepared by vacuum sintering at 1850?°C for 6?h using nanosized powder. The XRD, SEM, EDX and TEM results reveal that the single pyrochlore phase in the powder sample transforms to the coexistence of La-rich pyrochlore phase and Er-rich defect fluorite phase after high temperature sintering. The high excess amounts of La and Er favor the formation of pyrochlore structure. Despite the coexistence of two phases, the sample with 1?mm thickness shows excellent in-line transmittance in the visible to mid-infrared region (as high as 81% at 1100?nm). The upconversion and infrared emission under 980?nm exciting were measured and discussed as well. 相似文献
93.
V.A. Dekhtyarenko T.V. Pryadko D.G. Savvakin V.I. Bondarchuk G.S. Mogylnyy 《International Journal of Hydrogen Energy》2021,46(11):8040-8047
The influence of phase composition and microstructure of Ti42.75Zr27Mn20.25V10 alloy on its hydrogenation kinetic and phase composition of hydrogenated product was studied. It is established that the process of dissociation of hydrogen molecules begins on the surface of Laves phase crystallites. The dissolution of atomic hydrogen in the material volume leads to the formation of cracks in the intermetallic crystallites, which further appear as additional centers of dissociation of hydrogen molecules and noticeably accelerate the diffusion of hydrogen into the bulk material. It was shown that the Laves phase acts as a donor of atomic hydrogen for the BCC solid solution during hydrogenation of two-phase structure, initiating intensive hydrogenation of the BCC phase at room temperature. 相似文献
94.
Jiajia Lu Guangfu Qian Lin Luo Huibing He Shibin Yin 《International Journal of Hydrogen Energy》2021,46(1):676-682
The tungsten trioxide attracts less attention due to the low electron transfer kinetics that hinders the interaction of electrons and ions during the hydrogen evolution reaction (HER). But the oxygen vacancy strategy can inspire its electrocatalytic activity for HER because it has a positive effect on improving the charge transfer and compensating for the weak hydrogen adsorption of the tungsten trioxide. By synthesizing a series of substoichiometric tungsten oxides, we reveal the linear relationship between the catalytic activity and the content of oxygen vacancies, which indicates that the oxygen vacancy strategy is an achievable route to enhance the HER for metal oxides. 相似文献
95.
Mohamed R. Rizk Muhammad G. Abd El-Moghny 《International Journal of Hydrogen Energy》2021,46(1):645-655
We report on glycerol electro-oxidation in alkaline medium at macroporous Ni electrodes decorated with Cu particles. Macroporous Ni film is electrodeposited, using hydrogen bubbles as dynamic templates, atop of a Cu substrate. This film shows good electrocatalytic activity towards glycerol oxidation reaction (GOR). The Ni film is further decorated with Cu via spontaneous deposition from CuSO4 solution. This is done to enhance the catalytic activity of the film towards GOR. The morphology of the Cu-decorated Ni film is controlled using various additives such as KCl and (NH4)2SO4 which are added to the Cu deposition bath. The as-prepared Cu-decorated Ni films are characterized by electrochemical measurements, scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDS), X-ray diffraction (XRD), and X-ray photoelectron spectroscopy (XPS). It is found that these additives have tremendous effects on the morphology and the electrocatalytic activity of the decorating Cu particles.The decorated Ni foam showed superior electrocatalytic activity towards the GOR, as confirmed by the negative shift in the onset oxidation potential (ca. 100 mV) together with an increase in oxidation current that is up to 1.5-fold during the cyclic voltammetry (CV) measurements, compared to the undecorated Ni foam. 相似文献
96.
Zifei Yan Yubin Wang Chencan Du Jian Deng Guangsheng Luo 《American Institute of Chemical Engineers》2022,68(11):e17791
Ring-opening of epoxides with carboxylic acids has been widely used to prepare many high value intermediates in the polymer and pharmaceutical industries. Most of conventional processes proceeded in batch stirred reactors. As such they always suffer from low productivity and selectivity. Here we developed an advanced technology to perform the ring-opening reaction of epichlorohydrin with neodecanoic acid (NDA) for continuous production of 3-chloro-2-hydroxypropyl neodecanoate in a more efficient and safer way. A microreaction system where a microreactor connected to a stirred reactor was established. When the conversion of NDA rapidly reaching around 90% in a microreactor at 110°C, the reaction solution was transferred to a stirred reactor at 90°C. This two-stage operating mode can reduce the reaction time and improve the selectivity through free switching of temperature in the consecutive two reactors, thus substantially reducing the consumption of energy and materials. 相似文献
97.
Dobrydnev S. V. Alexandrova O. A. Rezvov Yu. G. 《Theoretical Foundations of Chemical Engineering》2022,56(3):362-366
Theoretical Foundations of Chemical Engineering - The reaction of nickel(II) hydroxide and a mixed ammonia–carbonate solution to form nickel(II) aqua–ammonia complexes is studied in the... 相似文献
98.
Fibre Chemistry - The paper presents an analysis of moisture absorption during the oscillated hydrothermal treatment of fibrous and dispersed materials, which is performed on the basis of kinetic... 相似文献
99.
Atomic Energy - An economic and mathematical model has been developed to determine the competitiveness of REMIX-A and -C uranium-plutonium fuel obtained by reprocessing spent fuel from thermal... 相似文献
100.
Carina A. Lämmle Adam Varady Thorsten G. Müller Dr. Caterina Sturtzel Michael Riepl Bettina Mathes Jenny Eichhorst Dr. Anje Sporbert Dr. Martin Lehmann Prof. Dr. Hans-Georg Kräusslich Dr. Martin Distel Dr. Johannes Broichhagen 《Chembiochem : a European journal of chemical biology》2021,22(3):548-556
Selective targeting of DNA by means of fluorescent labeling has become a mainstay in the life sciences. While genetic engineering serves as a powerful technique and allows the visualization of nucleic acid by using DNA-targeting fluorescent fusion proteins in a cell-type- and subcellular-specific manner, it relies on the introduction of foreign genes. On the other hand, DNA-binding small fluorescent molecules can be used without genetic engineering, but they are not spatially restricted. Herein, we report a photocaged version of the DNA dye Hoechst33342 (pcHoechst), which can be uncaged by using UV to blue light for the selective staining of chromosomal DNA in subnuclear regions of live cells. Expanding its application to a vertebrate model organism, we demonstrate uncaging in epithelial cells and short-term cell tracking in vivo in zebrafish. We envision pcHoechst as a valuable tool for targeting and interrogating DNA with precise spatiotemporal resolution in living cells and wild-type organisms. 相似文献