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911.
《Ceramics International》2021,47(23):33047-33056
In this paper, two kinds of composites constructed by UO3 nanoflakes (which is UO3·yNH3·xH2O, precisely) and different graphene oxide (GO) nanosheets (homemade GO, GO-h, and commercial GO, GO-c) were prepared via solution chemical reaction. The two kinds of GO share similar morphology and possess the same species of functional groups. Nevertheless, GO-h possesses higher oxidization degree and thus could adsorb more uranyl ions, and the corresponding composite shows a much more regular shape: UO3 nanoflakes and GO nanosheets cross each other, which would help overcome the disadvantage of graphene aggregation. As a result, homemade reduced graphene oxide (RGO-h) sheets inside the final UO2 pellets (named as UO2/GO-h) could construct a well-bulit thermally conductive network to enhance its thermal conductivity. However, similar RGO-c network cannot be observed in the UO2/GO-c pellest originated from GO-c. Therefore, only the thermal conductivity of UO2/GO-h pellet acquires a dramatic increase, 37.30% relative to UO2 pellet at 1200 °C, showing that UO2/GO-h possesses great potential for the development of novel UO2-based ATF fuels. 相似文献
912.
913.
Mikhail G. Akimov Alina M. Gamisonia Polina V. Dudina Natalia M. Gretskaya Anastasia A. Gaydaryova Andrey S. Kuznetsov Galina N. Zinchenko Vladimir V. Bezuglov 《International journal of molecular sciences》2021,22(2)
GPR55 is a GPCR of the non-CB1/CB2 cannabinoid receptor family, which is activated by lysophosphatidylinositol (LPI) and stimulates the proliferation of cancer cells. Anandamide, a bioactive lipid endocannabinoid, acts as a biased agonist of GPR55 and induces cancer cell death, but is unstable and psychoactive. We hypothesized that other endocannabinoids and structurally similar compounds, which are more hydrolytically stable, could also induce cancer cell death via GPR55 activation. We chemically synthesized and tested a set of fatty acid amides and esters for cell death induction via GPR55 activation. The most active compounds appeared to be N-acyl dopamines, especially N-docosahexaenoyl dopamine (DHA-DA). Using a panel of cancer cell lines and a set of receptor and intracellular signal transduction machinery inhibitors together with cell viability, Ca2+, NO, ROS (reactive oxygen species) and gene expression measurement, we showed for the first time that for these compounds, the mechanism of cell death induction differed from that published for anandamide and included neuronal nitric oxide synthase (nNOS) overstimulation with concomitant oxidative stress induction. The combination of DHA-DA with LPI, which normally stimulates cancer proliferation and is increased in cancer setting, had an increased cytotoxicity for the cancer cells indicating a therapeutic potential. 相似文献
914.
In this work, a deep learning accelerated homogenization framework is developed for prediction of elastic modulus of porous materials directly from their inner microstructures. The finite element method (FEM) and the homogenization theory are used to obtain the macroscopic properties of materials based on their microstructures. Based on a large dataset consisting of various microstructures and corresponding elastic properties via FEM, a deep convolutional neural network (CNN) is trained to capture the nonlinear functional relationship between the microstructure features and their macroscopic elastic properties. The deep learning model is finally well validated against extra new samples with excellent predictive performances. This demonstrates that the CNN deep learning model can be trusted as a surrogate model for the FEM based homogenization method, with the computation time being reduced by several orders of magnitude. The proposed deep learning framework is highly extendable for prediction of various macroscopic properties from microstructures. 相似文献
915.
Hongwei Shang Yaqin Li Yanghuan Zhang Dongliang Zhao Yan Qi Xiaoyi Xu 《International Journal of Hydrogen Energy》2021,46(34):17840-17852
In order to improve the hydrogen storage performances of TiFe-based alloys, a new type of TiFe0.8-mNi0.2Com (m = 0, 0.03, 0.05 and 0.1) alloys were prepared through vacuum medium-frequency induction melting. XPS results showed that the composition of surface oxide film contains TiO2, FeO and NiO for the cobalt-free alloy, and it also includes CoO and Co3O4 besides the above oxides for the cobalt-containing alloys. The activation temperature is 523, 403, 383 and 373 K for the TiFe0.8-mNi0.2Com (m = 0, 0.03, 0.05 and 0.1) alloys, respectively. The changes of the composition and microstructure of the surface oxide film are the root causes of the reduction of the activation temperature. XRD and SEM analyses showed that all the alloys are composed of the majority phase of TiFe phase and non-hydrogenated phase of Ti2Fe phase. Adding appropriate amount of cobalt is beneficial to inhibiting the generation of Ti2Fe phase and increasing the cell volume of TiFe phase. The hydrogenation capacity is proportional to the content of TiFe phase, which is 1.11, 1.48, 1.54 and 1.29 wt% for the TiFe0.8-mNi0.2Com (m = 0, 0.03, 0.05 and 0.1) alloys at 313 K, respectively. The hydrogenation plateau performance also is improved correspondingly. 相似文献
916.
Anupam Glorious Lobo Abdul Mujeeb Mahammad Nawaz Adeeb Aman A. P. Abdul Basith 《Polymer-Plastics Technology and Engineering》2016,55(16):1713-1719
Elucidation of the structure of naturally existing or synthesized substances is an important criterion in the study of materials to predict the application of the substance. In this study, polylactide was doped with nano-aluminium oxide and nano-cupric oxide with 1 and 3 mg of concentration variants. The interaction between the polymer matrix and the nanoparticles has been studied using Fourier transform infrared. Successful doping of the polymer has been observed. Attention has been drawn to check the intermolecular bonding in films having varying thicknesses, films prepared at higher sonication temperatures, and chemical homogeneity of the doped polymer films. 相似文献
917.
《International Journal of Hydrogen Energy》2019,44(59):31082-31093
Oxygen evolution reaction (OER) electrocatalysts play the critical role in efficiency and durability for different hydrogen production systems. We have successfully synthesized the earth abundant WO3 coupled with IrO2 as mixed oxide composite by a facile two-step chemical method. 50% reduction in noble metal contents (IW-50) followed by two times enhancement in activity, four-folds increase in bulk mass specific activity along with the stability of mixed oxide composite as compared to state –of –the art IrO2 catalyst are affirmed. Superior performance of mixed oxide composites are perceived due to four times increase in electrochemical surface area, reduction of Tafel slope, four-fold increase of turn over frequency, electronic distortion in Ir-4f spectrum of IW-50 along with the bridging of lattice oxygen atoms between iridium and tungsten metals. We believe that it would open up the new avenues for effective utilization of noble metal with high valence tungsten metal in corrosive environment. 相似文献
918.
作为平板结构钙钛矿太阳能电池的电荷传输层,金属氧化物薄膜对器件性能有重要影响. 系统性概述平板结构钙钛矿太阳能电池对金属氧化物薄膜形貌、电学、光学、化学及热等物理特性要求,并对目前在高效钙钛矿太阳电池制备中最有前景的金属氧化物电子传输层及空穴传输层材料特性及代表性工作进行总结. 针对大多数金属氧化物迁移率低、表面缺陷多及能级匹配差的问题,分析元素掺杂、表面改性、复合薄膜设计等手段解决的相关进展. 总结目前金属氧化物薄膜沉积技术现状及优缺点,探讨今后薄膜沉积技术发展、改进方向. 对低温沉积金属氧化物薄膜在柔性器件方面的应用进行展望. 相似文献
919.
An investigation of the electrical transport properties of graphene-oxide thin films 总被引:3,自引:0,他引:3
Gunasekaran Venugopal Karthikeyan KrishnamoorthyRajneesh Mohan Sang-Jae Kim 《Materials Chemistry and Physics》2012,132(1):29-33
The electrical transport properties of graphene-oxide (GO) thin films were investigated. The GO was synthesized by a modified Hummers method and was characterized by X-ray diffraction and UV-visible spectroscopy. The thin film of GO was made on a Si/SiO2 substrate by drop-casting. The surface morphology of the GO film was analyzed by using scanning electron microscopy and atomic force microscopy techniques. Temperature dependent resistance and current-voltage measurements were studied using four-terminal method at various temperatures (120, 150, 175, 200, 250 and 300 K) and their charge transport followed the 3D variable range hopping mechanism which was well supported by Raman spectra analysis. The presence of various functional groups in GO were identified by using high resolution X-ray photo electron (XPS) and Fourier transform infra red (FT-IR) spectroscopic techniques. Graphene-oxide thin film field effect transistor devices show p-type semiconducting behavior with a hole mobility of 0.25 cm2 V−1 s−1 and 0.59 cm2 V−1 s−1 when measured in air and vacuum respectively. 相似文献
920.
In this experimental study, the effects of 2D reduced graphene oxide (rGO) sheets on the properties of Portland cement paste in comparison to popularly reviewed nanomaterials like aluminium oxide nanopowder (n-Al2O3) and colloidal silicon dioxide nanoparticles (n-SiO2) were investigated. The addition of 0.02% rGO sheets by weight of cement increased the 7 and 28 days flexural strength up to 70% and 23% respectively when compared to control paste. Moreover, its incorporation substantially decreased the sizes of pores/voids in the paste, even compared to the other nanomaterials, as characterized by Mercury Intrusion Porosimetry (MIP) and 3D X-ray Computed Tomography (CT) aided with image analysis technique. The assessment of Portlandite content by Thermo-gravimetric Analysis did not indicate major differences between the pastes, with the exception of the paste incorporating nano-silica. Microstructural analysis by Fourier Transform Infrared Spectroscopy, X-ray diffraction and Scanning Electron Microscopy did not reveal any major differences between the control paste and the pastes incorporating nanomaterials. The overall results suggest that the performance of rGO was better in comparison to other two nanomaterials, despite the significantly lower amounts that were used in the paste. 相似文献