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排序方式: 共有1005条查询结果,搜索用时 109 毫秒
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Dipta Mukherjee Arjun Dey A. Carmel Mary Esther Debajyoti Palai N. Sridhara Parthasarathi Bera Manjima Bhattacharya A. Rajendra Anand Kumar Sharma Anoop Kumar Mukhopadhyay 《Ceramics International》2018,44(8):8913-8921
Smooth, uniform and crystalline vanadium oxide thin films were deposited on quartz by spin coating technique with four different rpm i.e., 1000, 2000, 3000 and 4000 and subsequently post annealed at 350, 450 and 550?°C in vacuum. Transmission electron microscopy (TEM), Field emission scanning electron microscopy (FESEM) and X-ray diffraction (XRD) techniques were utilized for microstructural characterizations and phase analysis, respectively, for vanadium oxide powder and deposited film. Nanorods were observed to be grown after vacuum annealing. X-ray photoelectron spectroscopy (XPS) technique was utilized to study the elemental oxidation state of deposited vanadium oxide films. Thermo-optical and electrical properties such as solar transmittance (τs), reflectance (ρs), absorptance (αs), infrared (IR) emittance (εir) and sheet resistance (Rs) of different thin films were evaluated. Based on the optical characteristics the optimized condition of the film processing was identified to be spin coated at 3000?rpm. Subsequently, the nanoindentation technique was utilized to measure hardness and Young's modulus of the optimized film. The measured nanomechanical properties were found to be superior to those reported for sputtered vanadium oxide films. Finally, temperature dependent phase transition characteristics of optimized vanadium oxide films were studied by differential scanning calorimetry (DSC) technique. Reversible and repeatable phase transition was found to occur in the range of 44–48?°C which was significantly lower than the phase transition temperature (i.e., 68?°C) of bulk VO2. 相似文献
3.
Superalloy 690 substrates containing mainly Cr and Ni aluminides on the uppermost surface, formed by atmospheric plasma spraying and heat treatment, were oxidized at 1273 K in air for 2 h. Quantitative X-ray photoelectron spectroscopy (XPS) analyses indicated that the outermost surface layer formed on aluminides is composed of ~ 21.0 at.% Al+3 (as Al2O3), 17.0 at.% Al0 (elemental aluminium), 1.4 at.% Cr+3 (as Cr2O3) and 60.5 at.% O (in Al2O3 and Cr2O3 and also includes oxygen contaminant). Surface sputtering for 5 min exhibited splitting of Cr2p3/2 peak into a doublet comprising Cr+3 (0.9 at.%) and Cr0 (0.4 at.%) with the presence of 1.15 at.% Ni0 in the surface layer that mainly contained ~ 37.3 at.% Al+3, 7.3 at.% Al0 and 52.9 at.% O. Surface sputtering for 15 min indicated surface composition similar to surface sputtered for 5 min but with a marked reduction in ratio of Al+3/Al0 (32.2 at.% Al+3/11.90 at.% Al0) in the surface layer. 相似文献
4.
Food Science and Biotechnology - A series of methyl salicylate (MeSA)/β-cyclodextrin (β-CD) inclusion complexes (ICs) were prepared at different MeSA concentrations by the... 相似文献
5.
Sukkum Ngullie Chang Debasish Kumar Dey Seong Taek Oh Won Ho Kong Kiu Hyung Cho Ebtesam M. Al-Olayan Buyng Su Hwang Sun Chul Kang Jae Gyu Park 《International journal of molecular sciences》2020,21(23)
Phorbol 12-myristate 13-acetate (PMA) is a potent tumor promoter and highly inflammatory in nature. Here, we investigated the toxic effects of PMA on different model system. PMA (10 μg) caused chromosomal aberrations on the Allium cepa root tip and induced mitotic dysfunction. Similarly, PMA caused embryonic and larval deformities and a plummeted survivability rate on zebrafish embryo in a dose-dependent manner. Persistently, PMA treatment on immortalized human keratinocyte human keratinocyte (HaCaT) cells caused massive inflammatory rush at 4 h and a drop in cell survivability at 24 h. Concomitantly, we replicated a cutaneous inflammation similar to human psoriasis induced by PMA. Herein, we used tangeretin (TAN), as an antagonist to counteract the inflammatory response. Results from an in vivo experiment indicated that TAN (10 and 30 mg/kg) significantly inhibited PMA stimulated epidermal hyperplasia and intra-epidermal neutrophilic abscesses. In addition, its treatment effectively neutralized PMA induced elevated reactive oxygen species (ROS) generation on in vitro and in vivo systems, promoting antioxidant response. The association of hypoxia-inducible factor 1-alpha (HIF-1α)-nuclear factor kappa-light-chain-enhancer of activated b cells (NF-κB) crosstalk triggered by PMA enhanced PKCα-ERK1/2-NF-κB pathway; its activation was also significantly counteracted after TAN treatment. Conclusively, we demonstrated TAN inhibited the nuclear translocation of HIF-1α and NF-κB p65. Collectively, TAN treatment ameliorated PMA incited malignant inflammatory response by remodeling the cutaneous microenvironment. 相似文献
6.
Sayantan Sil Arka Dey Soumi Halder Joydeep Datta Partha Pratim Ray 《Journal of Materials Engineering and Performance》2018,27(6):2649-2654
Here we have approached the plausible use of CuFeS2 nanocomposite as an acceptor in organic–inorganic hybrid solar cell. To produce CuFeS2 nanocomposite, hydrothermal strategy was employed. The room-temperature XRD pattern approves the synthesized material as CuFeS2 with no phase impurity (JCPDS Card no: 37-0471). The elemental composition of the material was analyzed from the TEM-EDX data. The obtained selected area electron diffraction (SAED) planes harmonized with the XRD pattern of the synthesized product. Optical band gap (4.14 eV) of the composite from UV–Vis analysis depicts that the synthesized material is belonging to wide band gap semiconductor family. The HOMO (? 6.97 eV) and LUMO (? 2.93 eV) positions from electrochemical study reveal that there is a possibility of electron transfer from MEH-PPV to CuFeS2. The optical absorption and photoluminescence spectra of MEH-PPV:CuFeS2 (donor:acceptor) composite were recorded sequentially by varying weight ratios. The monotonic blue shifting of the absorption peak position indicated the interaction between donor and acceptor materials. The possibility of electron transfer from donor (MEH-PPV) to acceptor (CuFeS2) was approved with photoluminescence analysis. Subsequently, we have fabricated a hybrid solar cell by incorporating CuFeS2 nanocomposite with MEH-PPV in open atmosphere and obtained 0.3% power conversion efficiency. 相似文献
7.
Liu Xian-Xian Fong Simon James Dey Nilanjan Crespo Rubén González Herrera-Viedma Enrique 《Applied Intelligence》2021,51(7):4162-4198
Applied Intelligence - Measuring the spread of disease during a pandemic is critically important for accurately and promptly applying various lockdown strategies, so to prevent the collapse of the... 相似文献
8.
Present study outlines a hybrid approach using Finite Element Method (FEM)–Response Surface Method (RSM)–Genetic Algorithm (GA) to predict the crack parameters, namely crack position and crack depth ratio with the help of only the measured natural frequencies of cracked thin walled beams. Numerical experimental trials of cracked beams have been conducted based on design of experiment (DOE) approach using an improved Finite element model. The improvement has been achieved by consideration of warping stiffness in cracked angle section beam. Thereafter, regression analysis has been conducted to construct Response Surface Function (RSF). Optimum crack parameters were then calculated using GA by minimizing an objective function which has been formed as the root mean square (RMS) of the residuals between RSFs and measured frequencies. Results of the study indicate that, the proposed approach performs with excellent accuracy and it does not require the response of an uncracked beam as benchmark information. 相似文献
9.
Meticulous analysis and consequences of microstructure changes on melt rheology and dynamic viscoelasticity of thermoplastic vulcanizates upon reprocessing 下载免费PDF全文
Pranab Dey Kinsuk Naskar Golok B. Nando Biswaranjan Dash Sujith Nair G. Unnikrishnan 《应用聚合物科学杂志》2014,131(23)
Thermoplastic vulcanizates (TPVs), which are a special class of elastomer alloy, prepared by dynamic vulcanization possess unique morphology of finely dispersed micron‐size cross‐linked elastomeric particles in a continuous thermoplastic matrix. The present study investigates the microstructure formation of elastomeric phase and its associated morphological changes during reprocessing of TPVs based on poly[styrene‐b‐(ethylene‐co‐butylene)‐b‐styrene] triblock co‐polymer (S‐EB‐S) and solution polymerized styrene butadiene elastomer (S‐SBR) by scanning electron microscopy and atomic force microscopy. Semi‐efficient and efficient sulfur‐based curing systems have been adopted to cure the elastomeric phase and a comparative study has been made to demonstrate and explain the effect of reprocessing on the melt rheology and dynamic viscoelasticity of the TPVs. The present work also provides a better insight and guidance to control the microstructure of the cross‐linked elastomeric phase to prepare selectively co‐continuous or dispersed phase morphology. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 41182. 相似文献
10.
Yuanyuan Zhang Li Wang Soumyadeep Dey Mawadda Alnaeeli Sukanya Suresh Heather Rogers Ruifeng Teng Constance Tom Noguchi 《International journal of molecular sciences》2014,15(6):10296-10333
Erythropoietin (EPO) regulation of red blood cell production and its induction at reduced oxygen tension provides for the important erythropoietic response to ischemic stress. The cloning and production of recombinant human EPO has led to its clinical use in patients with anemia for two and half decades and has facilitated studies of EPO action. Reports of animal and cell models of ischemic stress in vitro and injury suggest potential EPO benefit beyond red blood cell production including vascular endothelial response to increase nitric oxide production, which facilitates oxygen delivery to brain, heart and other non-hematopoietic tissues. This review discusses these and other reports of EPO action beyond red blood cell production, including EPO response affecting metabolism and obesity in animal models. Observations of EPO activity in cell and animal model systems, including mice with tissue specific deletion of EPO receptor (EpoR), suggest the potential for EPO response in metabolism and disease. 相似文献