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排序方式: 共有511条查询结果,搜索用时 156 毫秒
1.
Abhishek Nigam Sheetal Saini Ambak Kumar Rai S.J. Pawar 《Ceramics International》2021,47(14):19515-19525
In this study, MgO nanoparticles were successfully fabricated and incubated inside ZnO NPs to form MgO/ZnO nanocomposite for biomedical applications. The x-ray diffraction analysis of MgO, ZnO, and MgO/ZnO has shown the single-phase x-ray diffraction patterns through X'pert High score. The crystallite sizes were calculated as 18 nm, 42 nm, and 53 nm, respectively. The average particle size of MgO, ZnO, and MgO/ZnO nanopowders depicted from secondary electron images of field emission electron microscopy were 56 nm, 400 nm, and 450 nm, respectively. The presence of MgO NPs inside ZnO NPs was confirmed by transmission electron microscopy. The elemental dispersive spectroscopy of MgO, given the peaks of oxygen and magnesium, also showed only zinc and oxygen peaks in ZnO, which confirms no other impurities in MgO and ZnO powders. The elemental analysis of MgO/ZnO nanocomposite showed the peaks of Zinc and Oxygen, along with a tiny peak of Mg. The photoluminescence and UV–vis spectroscopy revealed the absorbance fluorescence limit of the nanomaterials. Fourier transform infrared spectroscopy confirmed the several groups present in the nanocomposite. The biocompatibility of MgO, ZnO, and MgO/ZnO was observed with human peripheral blood mononuclear cells. The cytotoxicity studies were also performed against human cancer (liver and breast) cell lines. The MgO, ZnO, and MgO/ZnO exhibited the antimicrobial properties against Escherichia coli and Staphylococcus aureus. 相似文献
2.
Wireless Personal Communications - Now-a-days the most common pretentious disease is the lung cancer, which has become more prevalent in the world that primarily infects the pulmonary nodules of... 相似文献
3.
Fire Technology - The tendency of self-ignition of coal is the root cause of underground coal fires (UCFs). A parametric study is carried out on a lab-scale experimental setup developed based on... 相似文献
4.
Polymer Bulletin - The present paper is focused on the synthesis and optimization of a green PVA-co-poly(MAA) adsorbent by free radical polymerization using N,N′-methylene-bis-acrylamide and... 相似文献
5.
This article presents a design methodology for linearizing GaN HEMT amplifiers based on splitting a large FET into multiple parallel FETs with same total gate periphery and by biasing them individually. By varying the biases, the magnitude and the phase of the IMD3 components at the output of FET changes. A detailed simulation methodology using commercial microwave CAD software is presented. Simulation results show that by biasing one device in Class AB and other(s) in deep Class AB mode, IMD3 components of parallel FETs can be made out of phase to each other leading to cancellation and improvement in linearity. Three prototype circuits were simulated using (a) a single 5 mm FET (1 × 5 mm), (b) two parallel 2.5 mm FETs (2 × 2.5 mm), and (c) four parallel 1.25 mm FETs (4 × 1.25 mm), for a total gate periphery of 5 mm, over the frequency range of 0.8 to 1.0 GHz. IMD3 improvement up to 20 dBc was achieved with the 4 × 1.25 mm circuit when the FET biases were optimized. Measurement results show improvement in linearity up to 20 dBc for 4 × 1.25 mm circuit. The proposed method improves linearity without a substantial penalty on the power consumption and is straightforward to implement. 相似文献
6.
Ram Gopal Ankit Goyal Ajay Saini Meena Nagar Nikita Sharma Deepak Kumar Gupta Veena Dhayal 《Ceramics International》2018,44(16):19099-19105
Synthesis of mono-crystalline Ga2O3 Nanorods was done by sol-gel transformation of gallium(III) isopropoxide (Ga(OPri)3). XRD studies were done to determine the planes and crystal structure of synthesized nanorods that showed the synthesis of β-Ga2O3(a). TEM studies of synthesized Ga2O3 confirmed the synthesis of monocrystalline β-Ga2O3 nanorods. To study the effect of precursor chemistry and to determine role of precursor structures on the crystal structure, phase and morphology of the Ga2O3, a new modified precursor complex was synthesized. The reaction of Ga(OPri)3 with N-phenylsalicylaldimine, [C6H4(OH)CH=N(C6H5)] in 1:1?M ratio yielded [{(H5C6)N?=?CH-C6H4O}Ga(OPri)2]. The newly synthesized complex was characterized by elemental analyses, molecular weight measurement, FT-IR and NMR (1H and 13C) spectral studies. Spectral studies of the modified complex suggest the presence of bi-dentate mode of attachment of Schiff's base in the solution state. Sol-gel transformations of [{(H5C6)N?=?CH-C6H4O}Ga(OPri)2] in organic medium, yielded γ-Ga2O3(b), as found by XRD studies. TEM image of the sample (a) revealed the formation of nano-rods of oxide with average diameter of ~100?nm whereas the TEM image of sample (b) showed presence of nano-sized particles of oxide with average particle size of 10?nm. Morphological and compositional studies of synthesized samples (a) and (b) were carried out using SEM and EDX. The method provides a possibility of large scale synthesis of dissimilar shaped and pure Ga2O3 nanoparticles. 相似文献
7.
8.
Roy Partha Pratim Kumar Pradeep Patidar Shweta Saini Rajkumar 《Multimedia Tools and Applications》2021,80(8):11671-11689
Multimedia Tools and Applications - Leap motion sensor provides a new way of interaction with computers or mobile devices. With this sensor, users can write in air by moving palm or finger, thus,... 相似文献
9.
Singh Dalip Saini Ajay Dhayal Veena Agarwal Dinesh Chandra 《Protection of Metals and Physical Chemistry of Surfaces》2019,55(4):682-688
Protection of Metals and Physical Chemistry of Surfaces - Dense alumina coatings were fabricated over aluminum alloy via dip coating method using oxime-modified aluminum(III) isopropoxide as a... 相似文献
10.
Surrounding vegetation, animal, human and microbiological decomposition are the strong source of humic acid (HA) falling into the surface water bodies through rain runoff in the monsoon. HA contains various functional groups, such as carboxylic, phenolic, hydroxyl, and quinine, which are the major foulant. Contact of HA may have an adversarial health issue to human beings namely goiter, black foot, and cancer disease. The maximum permissible limit of HA in drinking water should be less than 2 ppm as per the Environmental Protection Agency (EPA). The membrane technology has prevailed a prominent place worldwide in chemical, water and wastewater treatment technologies. The proposed work is focused on the blending of organic-water soluble polymer polyethylene glycol 6000 as a pore-forming agent and inorganic salt lithium bromide (LiBr) as membrane morphology modifier with polyvinylidene fluoride host polymer in the N,N-Dimethylacetamide solvent. All fabricated membranes were characterized for functional groups and morphology. The total number of pores per unit surface area of membrane for membranes M-LiBr-0, M-LiBr-1, M-LiBr-2, and M-LiBr-3 are 2 × 1013, 2.3 × 1014, 2.7 × 1014 and 2.82 × 1014, respectively. The static water contact angle was decreased from 68.2° to 50.6° with an increase in the content of LiBr from 0 to 3 wt%. The order of pure water flux and hydraulic permeability of the membrane was M-LiBr-0 < M-LiBr-1 < M-LiBr-2 < M-LiBr-3. The HA rejection of the membrane was also increased from 90.13% to 96.24% with LiBr content due to a decrease in pore size of the membrane with the addition of LiBr content. 相似文献