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991.
Transition-metal oxides are considered to be a promising anode material for lithium-ion batteries(LIBs)due to their high capacities,low cost,and ease of synthesis.Herein,a hybrid nanosheet composed of uniform MoO_2 nanoparticles(NPs) homogeneously immobilized on the reduced graphene oxide nanosheets(MoO_2 NP@rGO) is first synthesized by a self-templating and subsequent calcination treatment.The unique two-dimensional hybridnanosheets provides several merits.rGO can be used as a favorable support for the loading of electrochemically active MoO_2 NPs.Meanwhile,MoO_2 NPs can effectively prevent the stacking of the rGO.The effective combination of MoO_2 NPs and rGO nanosheets furnish additional electrochemically interfacial active sites for extra lithium ion sto rage.Noticeably,the as-fabricated hybrid nanosheets deliver a reversible capacity of 641 mAh/g after 350 cycles at a current density of 1000 mA/g with a good rate capability.The greatly enhanced lithium storage properties of MoO_2 NP@rGO indicate the importance of elaborate construction of novel hybrid hierarchical structures. 相似文献
992.
Morphology and crystal phase evolution of GeO2 in liquid phase deposition (LPD) process is investigated. Rod-like solid phases precipitate out of solution ahead of truncated cube-like phases. SEM, XRD and TEM analyses reveal that the two sorts of solid phases are tetragonal GeO2 and hexagonal GeO2, respectively. The tetragonal GeO2 phases start to experience a re-dissolving process as soon as the hexagonal phases come into being. The prior precipitation of the rod-like phase arises from a relatively low solute saturation of tetragonal GeO2. Fast growth of a tetragonal GeO2 phase along [111] direction leads to development of a rod-like shape. The re-dissolving phenomenon does not agree with the classic growth kinetics of crystals but is strongly favored by our calculations based on thermodynamics. The GeO2 solutes are released in a fluctuant way by germanate ions, which promotes the occurrence of the re-dissolution phenomenon. The current researches open a door for room-temperature LPD growth of not only the hexagonal GeO2 particles and film but also the one-dimensional tetragonal GeO2 product. 相似文献
993.
994.
Kaiqi Pan Shuhua Peng Yingying Chu Kang Liang Chun H. Wang Shuying Wu Jiangtao Xu 《Journal of polymer science. Part A, Polymer chemistry》2020,58(21):3069-3081
Hydrogel-based strain sensors have been attracting immense attention for wearable electronic devices owing to their intrinsic soft characteristics and flexibility. However, developing hydrogel sensors with hightensile strength, stretchability, and strain sensitivity remains a great challenge. Herein, we report a technique to synthesize highly sensitive hydrogel-based strain sensors by integrating carbon nanofibers (CNFs) with a double-network (DN) polymer hydrogel matrix comprising of a physically cross-linked agar network and a covalently cross-linked polyacrylamide (PAAm) network. The resultant nanocomposite sensors display superior piezoresistive sensitivity with a hightrue gauge factor (GFT = 1.78) at an ultrahigh strain of 1,000%, a fast response time and linear correlation of ln(R/R0) and ln(L/L0) up to 1,000% strain. Most significantly, these sensors possess highmechanical strength (~0.6 MPa) and superb durability (>1,000 cycles at strain of 100%), stemming from the effective energy dissipation mechanism of the first agar network acting as sacrificial bonds and the CNFs serving as dynamic nanofillers. The combination of highstrain sensitivity and ultrahigh stretchability of hydrogel sensors makes it possible to sense both small mechanical deformations induced by human motions and large strain up to 1,000%. 相似文献
995.
We report a simple and effective method to produce copper-doped carbon aerogel (Cu-CA) using sodium alginate as a carbon precursor through ion crosslinking and high-temperature carbonization. Results indicate that Cu-alginate has a 3D scaffold structure with pores. The effect of using different metal salt mass ratios of Cu-CA on the catalytic thermal decomposition of AP is also investigated. The thermal decomposition temperature of AP decreases by 94.24 °C, and the activation energy of the decomposition reaction is reduced by 45.7 kJ/mol. These results demonstrate that the composite exhibits superior catalytic performance compared with a single-component transition metal salt. 相似文献
996.
Shili Qin Hongshou Cui Hongtao Chu Lidi Gao Xue Li Yimin Tang Xingyu You Qing Dong 《Electrophoresis》2022,43(16-17):1710-1723
We developed a novel, convenient and low-cost one-pot strategy for preparing a zeolitic imidazolate framework-8 (ZIF-8)–silica hybrid monolithic column by adding ZIF-8 directly to a polymer solution of the silica matrix. The simulated stationary phase and monolithic column prepared under optimal conditions were characterized using X-ray diffraction, scanning electron microscopy, Fourier-transform infrared spectroscopy, thermogravimetric analysis nitrogen physisorption and zeta potential. The results obtained confirmed the successful introduction of ZIF-8 into the silica monolithic column, and the prepared monolithic column exhibited good permeability and physicochemical stability. A capillary electrochromatography method was developed based on a ZIF-8–silica hybrid monolithic column through which 15 mixed amino acids, 4 neutral compounds, 4 nipagin esters and 2 chlorinated fungicides were separated in 14, 5, 7 and 6 min, respectively, under optimal conditions. The relative standard deviations retention times and column efficiencies in run-to-run, day-to-day and column-to-column varied in the ranges of 1.90%–2.21%, 2.13%–2.51% and 3.08%–6.65%, respectively, which demonstrated that ZIF-8–silica hybrid monolithic column exhibited satisfactory reproducibility and stability. The incorporation of ZIF-8 into a silica monolithic column is a promising method for preparing novel monolithic columns composed of a metal–organic framework. 相似文献
997.
A direct analytical method based on dual ambient plasma ion source tandem mass spectrometry was used for the simultaneous determination of four sterols in the environment. This technology has very high sensitivity and the method detects the four sterols in methanol–water (1:3) solutions with limits of detection (LOD) and limits of quantification (LOQ) ranging from 1.2 ng/L to 6.9 ng/L and 7.6 ng/L to 10.0 ng/L, respectively. The method was also used to test water quality at three locations within the city and successfully detected all four sterols at very low concentrations. The dual plasma source tandem mass spectrometry technique is extremely simple, rapid, sensitive and highly efficient compared to other traditional methods, providing a useful screening tool for sterols in water. 相似文献
998.
Yu T. C. Nie G. J. Zhong Z. Chu F. Y. Cao X. J. 《Mechanics of Composite Materials》2021,57(1):115-124
Mechanics of Composite Materials - The analytical solution of the bending problem for a clamped rectangular plate with a variable in-plane stiffness is found by using the method of superposition.... 相似文献
999.
Tianyu Long Shiwei Pan Dr. Shengqing Zhu Prof. Dr. Lingling Chu 《Chemistry (Weinheim an der Bergstrasse, Germany)》2022,28(15):e202104080
We report a visible-light-induced three-component sulfonyl-heteroarylation of vinyl ethers with sulfinates and five-membered heteroaryl chlorides. This protocol proceeds via electron-donor-acceptor (EDA) complexes between sulfinates and heteroaryl chlorides, giving β-sulfonyl alkyl five-membered heteroarenes with high efficiency and excellent regioselectivity under mild and catalyst-free conditions. Utilization of CF3SO2Na or CF2HSO2Na as coupling partners further achieves three-component fluoromethyl-arylation of vinyl ethers, furnishing a series of valuable CF3/CF2H-incorporated alkyl heterocycles under mild conditions. 相似文献
1000.
Capacitors are critical components in many advanced electronic and electrical systems,such as pulse power systems,due to their fast charging-discharging speed and high power density[1-4].The ever-increasing demand for compact energy storage devices requires the dielectrics,which are the energy storage materials in capacitors,to have a higher energy density and low dielectric loss[2,3].Furthermore,a stable high-temperature performance is another important parameter to be considered for some applications in which high-temperature conditions are present,such as hybrid vehicles[4-7]. 相似文献