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1.
We present the thermoelectric and superconducting properties of the bulk misfit-layered (SnSe)1.17(TaSe2) compound with the critical temperature (Tc ~ 3.8 K). From XRD and electrical resistivity, the anisotropic properties of the misfit-layered compound by the preferred orientation were observed. The zero-temperature-limit upper critical field Hc2(0) and coherence length ξ are obtained by Hc2(0) = 8.94 T and ξ = 6.1 nm. The electron-phonon coupling constant (λe-p = 0.735) and the specific heat jump (ΔCe/γTc ~ 1.4) imply that the (SnSe)1.17(TaSe2) compound is a weak coupled conventional s-wave superconductor. Density functional theory (DFT) calculation results show that some electronic charge transfers from the SnSe layers into the TaSe2 layers. In addition, the thermoelectric properties of the bulk misfit-layered (SnSe)1.17(TaSe2) compound show significant anisotropic properties. 相似文献
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Volatile organic compounds(VOCs) have become one of the most serious threats to human health and eco-environment due to their volatility, toxicity and diffusivity, etc. Catalytic completely oxidation had been regarded as a highly efficient strategy for the VOCs abatement. Metal or metal oxides supported on zeolite have been considered as superior catalysts for the treatment of VOCs. Among them, Beta zeolites have attracted many attentions due to their unique structure and consequently catalytic properties in the oxidation of VOCs. The progresses and developments made in the understanding and design of Beta zeolites-based catalysts in the completely oxidation of VOCs in the past two decades have been systematically summarized in this review. 相似文献
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《Arabian Journal of Chemistry》2022,15(9):104086
In this paper, we studied commercially available precipitated rice husk silica (RHS) with conventional precipitated silica, which has nearly the same surface area, and replaced part of the carbon black with RHS and conventional silica in a basic tread formulation. All formulations were mixed with the same amount of filler during the study. Silica was used at 15, 30 and 50 phr loading, and part of the carbon black was replaced by silica. Compound curing characteristics, physical properties, rebound resilience, heat generation, abrasion loss, dynamic properties and morphology were analyzed. The results indicated that RHS demonstrated compound properties comparable to those of conventional silica. As part of the carbon black was replaced with conventional silica, a slower cure rate, higher rebound resilience, lower heat generation, lower abrasion loss, and lower tan delta were observed with no significant change in physical properties, but some changes in physical properties were observed using one way ANOVA analysis. We found the same trend when replacing part of the carbon black with RHS, such as a slower cure rate, higher rebound resilience, lower heat generation, lower abrasion loss, and lower tan delta with no significant change in physical properties, but some changes in physical properties were observed using one way ANOVA. This sustainable material could be used to replace conventional silica in tire compounding, as well as to replace a portion of carbon black with RHS for improved heat build-up, rolling resistance, and abrasion loss. 相似文献
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通过“燃煤污染与防治”“金属矿物的开发利用”等2个典型的元素化合物教学案例,探讨如何将元素化合物的学习置于一定挑战性的问题情境中,形成问题解决基本思路,从化学视角分析解决实际问题,促进学生化学学科核心素养的发展。 相似文献
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复合材料广泛应用于航空航天等领域,追求轻量化设计已经成为研究重点。对复合材料层合板质量优化设计,可以减少层合板的纤维用量,减小层合板的质量,降低成本。首先研究复合材料层合板在承受轴向载荷时,产生的形变量、应力示意图,分析容易发生失效部位;以层合板铺层厚度为设计变量,最大应变、铺层比例等为约束条件,最小化层合板质量为优化目标,对碳纤维复合材料层合板铺层厚度等设计变量进行优化,利用强度理论对优化结果进行校核,结合力学试验对比分析优化前后层合板力学性能。结果表明:碳纤维复合材料层合板经过优化后,总质量减轻约16.7%,优化后的层合板满足复合材料强度理论,实验结果与软件仿真具有一致性,说明优化方法是合理可靠的。 相似文献
8.
The photoactivity of CdS nanorods was greatly improved by amino functionalized accordion-like MXene and spherical ZnSnO3. MXene possesses good electron transfer capability and ZnSnO3 presents matched energy band with CdS, which deeply accelerate the electron transfer and prevent the recombination of photogenerated electron-hole pair, leading to a strong photoelectrochemical (PEC) response. Taking the merit of the improved photoactivity of CdS nanorods, a novel PEC biosensor was constructed for DNA hydromethylation detection based on immune recognition of target molecule, where 5-hydroxymethyl-2′-deoxycytidine triphosphate (5hmdCTP) was employed as detect target, CdS/MXene was used as photoactive material, and ZnSnO3 was adopted as signal amplification unit. Under enzymatic covalent reaction of –CH2OH of 5hmdCTP with –NH2 of MXene, 5hmdCTP was specifically recognized and captured. Then, taking advantages of the covalent reaction between phosphate group of 5hmdCTP and ZnSnO3, the signal amplification unit was captured. Under the optimum conditions, this PEC biosensor presents wide linear range of 0.008–100 nM and low detection limit of 4.21 pM (3σ). The applicability of the developed method was evaluated by investigating the effect of Cd2+ and perfluorohexane compound pollutant on 5-hydroxymethylcytosine content in the genomic DNA of the roots and leaves of wheat seedlings. 相似文献
9.
Although great progress has been made in the advancement of nanozymes, most of the studies focus on mimicking peroxidase, oxidase, and catalase, while relatively few studies are used to mimic laccase. However, the use of nanomaterials to mimic laccase activity will have great potential in environmental and industrial catalysis. Herein, Cu/CuO-graphene foam with laccase-like activity was designed for the identification of phenolic compounds and the detection of epinephrine. In a typical experiment, the formation mechanism of Cu/CuO-graphene foam was investigated during the pyrolysis process by thermogravimetric-mass spectrometry. As a laccase mimic, Cu/CuO-graphene foam exhibited excellent catalytic activity with a Michaelis-Menten constant and a maximum initial velocity of 0.17 mmol/L and 0.012 mmol∙L-1∙s-1, respectively. Based on this principle, Cu/CuO-graphene foam nanozyme could differentially catalyze phenolic compounds and 4-aminoantipyrine for simultaneous identification of phenolic compounds. Furthermore, a colorimetric sensing platform was fabricated for the quantitative determination of epinephrine, showing linear responses to epinephrine in the range of 3 mg/mL to 20 mg/mL with the detection limit of 0.2 mg/mL. The proposed Cu/CuO-graphene foam nanozyme could be applied for the identification of phenolic compounds and the detection of epinephrine, showing great potential applications for environmental monitoring, biomedical sensing, and food detection fields. 相似文献
10.
Monica Averna Alessandro A. Casazza Antonino Martines Marco Pedrazzi Alice Franchi Roberta De Tullio 《Natural product research》2019,33(10):1449-1455
We are reporting in the present study that molecules extracted from olive pomace prevent cell death induced by Ca2+-overloading in different cell types. Exposure of cells to these molecules counteracts the Ca2+-induced cell damages by reducing the activation of the Ca2+-dependent protease calpain, acting possibly through the modification of the permeability to Ca2+ of the plasma membrane. The purification step by RP-HPLC suggests that effective compound(s), differing from the main biophenols known to be present in the olive pomace extract, could be responsible for this effect. Our observations suggest that bioactive molecules present in the olive pomace could be potential candidates for therapeutic applications in pathologies characterised by alterations of intracellular Ca2+ homeostasis. 相似文献