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排序方式: 共有204条查询结果,搜索用时 15 毫秒
1.
Mohammad Hemmat Esfe Mousa Rejvani Rostam Karimpour Ali Akbar Abbasian Arani 《Journal of Thermal Analysis and Calorimetry》2017,128(3):1359-1371
In the present paper, the effects of temperature and volume fraction on thermal conductivity of SWCNT–Al2O3/EG hybrid nanofluid are investigated. Single-walled carbon nanotube with outer diameter of 1–2 nm and aluminum oxide nanoparticles with mean diameter of 20 nm with the ratio of 30 and 70%, respectively, were dispersed in the base fluid. The measurements were conducted on samples with volume fractions of 0.04, 0.08, 0.15, 0.3, 0.5, 0.8, 1.5 and 2.5. In order to investigate the effects of temperature on thermal conductivity of the nanofluid, this characteristic was measured in five different temperatures of 30, 35, 40, 45 and 50 °C. The results indicate that enhancement of nanoparticles’ thickness in low volume fractions and at any temperature causes a considerable increment in thermal conductivity of the nanofluid. In this study, the highest enhancement of thermal conductivity was 41.2% which was achieved at the temperature of 50 °C and volume fraction of 2.5%. Based on the experimental data, an experimental correlation and a neural network are presented and for thermal conductivity of the nanofluid in terms of volume fraction and temperature. Comparing outputs of the experimental correlation and the designed artificial neural network with experimental data, the maximum error values for the experimental correlation and the artificial neural network were, respectively, 2.6 and 1.94% which indicate the excellent accuracy of both methods in prediction of thermal conductivity. 相似文献
2.
Kanchan Bhardwaj Ana Sanches Silva Maria Atanassova Rohit Sharma Eugenie Nepovimova Kamil Musilek Ruchi Sharma Mousa A. Alghuthaymi Daljeet Singh Dhanjal Marcello Nicoletti Bechan Sharma Navneet Kumar Upadhyay Natlia Cruz-Martins Prerna Bhardwaj Kamil Ku
a 《Molecules (Basel, Switzerland)》2021,26(10)
Conifers have long been recognized for their therapeutic potential in different disorders. Alkaloids, terpenes and polyphenols are the most abundant naturally occurring phytochemicals in these plants. Here, we provide an overview of the phytochemistry and related commercial products obtained from conifers. The pharmacological actions of different phytochemicals present in conifers against bacterial and fungal infections, cancer, diabetes and cardiovascular diseases are also reviewed. Data obtained from experimental and clinical studies performed to date clearly underline that such compounds exert promising antioxidant effects, being able to inhibit cell damage, cancer growth, inflammation and the onset of neurodegenerative diseases. Therefore, an attempt has been made with the intent to highlight the importance of conifer-derived extracts for pharmacological purposes, with the support of relevant in vitro and in vivo experimental data. In short, this review comprehends the information published to date related to conifers’ phytochemicals and illustrates their potential role as drugs. 相似文献
3.
El-Shahat M. Mochtar M. Rashad M. M. Mousa M. A. 《Journal of Solid State Electrochemistry》2021,25(3):803-819
Journal of Solid State Electrochemistry - Graphene (G) and ternary nanocomposites of Mn3O4, TiO2, and reduced graphene oxide(rGO) electrodes have been prepared for supercapacitor applications. The... 相似文献
4.
Luminita Georgeta Confederat Cristina Gabriela Tuchilus Maria Dragan Mousa Shaat Oana Maria Dragostin 《Molecules (Basel, Switzerland)》2021,26(12)
Despite the advantages presented by synthetic polymers such as strength and durability, the lack of biodegradability associated with the persistence in the environment for a long time turned the attention of researchers to natural polymers. Being biodegradable, biopolymers proved to be extremely beneficial to the environment. At present, they represent an important class of materials with applications in all economic sectors, but also in medicine. They find applications as absorbers, cosmetics, controlled drug delivery, tissue engineering, etc. Chitosan is one of the natural polymers which raised a strong interest for researchers due to some exceptional properties such as biodegradability, biocompatibility, nontoxicity, non-antigenicity, low-cost and numerous pharmacological properties as antimicrobial, antitumor, antioxidant, antidiabetic, immunoenhancing. In addition to this, the free amino and hydroxyl groups make it susceptible to a series of structural modulations, obtaining some derivatives with different biomedical applications. This review approaches the physico-chemical and pharmacological properties of chitosan and its derivatives, focusing on the antimicrobial potential including mechanism of action, factors that influence the antimicrobial activity and the activity against resistant strains, topics of great interest in the context of the concern raised by the available therapeutic options for infections, especially with resistant strains. 相似文献
5.
Russian Journal of Applied Chemistry - Industrial by product dumped from iron making industry (slag) has been modified by various chemical agents, particularly, paraffin wax, liquid nitrile... 相似文献
6.
Saleh Al-Omari Nawash Alghezawi Mousa Al-Noaimi Akram Aqili Ibrahim F. Al-Hamarneh Mohammad Marashdeh 《Journal of fluorescence》2014,24(3):835-839
The shift of the Q-band of sodium zinc(II)-2,9,16,23-phthalocyanine tetracarboxylate (ZnPc(COONa)4) to about 800 nm is attributed to the influence of the electron-donating property of the carboxylate groups substituted in the β–position. ZnPc(COONa)4 which was found to have a symmetry of D 2h characterized by a splitting of the Q transition. This splitting was interpreted by the formation of dianionic symmetric ZnPc(COONa)4 resulting from the dissociation of the pyrrole protons as well as the possibility of Na+ dissolution of ZnPc(COONa)4 in the aqueous solution of NaOH. 相似文献
7.
In this paper, we propose a metamaterial film bounded by a nonlinear cover and a dielectric substrate as a THz wave sensor. The dispersion characteristics and magnetic field profiles have been derived, computed and analyzed. Confinement of the light waves was found to increase with both nonlinearity and frequency. We believe our results can be used to design novel tunable future sensors. 相似文献
8.
Mousa M.A. Imran 《Physica B: Condensed Matter》2011,406(22):4289-4295
Results of crystallization kinetics, viscosity, specific heat, thermal stability, and glass forming ability of Se85−xSb15Snx (x=10, 11, 12.5, and 13) chalcogenide glasses, using differential scanning calorimeter (DSC), under non-isothermal condition have been reported and discussed. The variation of the peak temperature of crystallization Tp with the heating rate β has been used to investigate the growth kinetics using Kissinger, Takhor, and Augis-Bennet models. The activation energy of crystallization Ec has been found to increase with Sn content and the crystal growth occurs in one dimension. The increasing trend of Ec is interpreted in terms of enhancement of the degree of cross-linking due to the formation of SnSe4/2 structural units of energies higher than that of Se-Se and Se-Sb bond energies. The viscosity η against 1/T curves has also been drawn and indicated that the atoms of ternary Se-Sb-Sn glasses required more energy, with the addition of Sn, to complete the transformation from amorphous to crystalline state. The demand for thermal stability has been ensured through the calculations of the enthalpy released ΔHc during the crystallization process and S-parameter, while the obtained values of the reduced glass transition temperature Trg and Hurby number HR have been used to estimate the glass forming ability (GFA). Results reveal that, both thermal stability and GFA enhanced with increasing Sn content and the studied samples were prepared from strong glass-forming liquids. The obtained values for the specific heat difference ΔCp, between the equilibrium liquid and the glass, have been found to decrease with increasing Sn content and are in support of the results of thermal stability and GFA. 相似文献
9.
Mousa M.A. Imran 《Physica B: Condensed Matter》2011,406(3):482-487
Crystallization and glass transition kinetics of Se70−xGa30Inx (x=5, 10, 15, and 20) semiconducting chalcogenide glasses were studied under non-isothermal condition using a Differential Scanning Calorimeter (DSC). DSC thermograms of the samples were recorded at four different heating rates 5, 10, 15, and 20 K/min. The variation of the glass transition temperature (Tg) with the heating rate (β) was used to calculate the glass transition activation energy (Et) using two different models. Meanwhile, the variation of the peak temperature of crystallization (Tp) with β was utilized to deduce the crystallization activation energy (Ec) using Kissinger, Augis-Bennet, and Takhor models. Results reveal that Et decreases with increasing In content, while both Tg and Ec exhibit the opposite behavior, and the crystal growth occurs in one dimension. The variation of these thermal parameters with the average coordination number <Z> was also discussed, and the results were interpreted in terms of the type of bonding that In makes with Se. Assessment of thermal stability and glass forming ability (GFA) was carried out on the basis of some quantitative criteria and the results indicate that thermal stability is enhanced while the crystallization rate is reduced with the addition of In to Se-Ga glass. 相似文献
10.
Journal of Solid State Electrochemistry - Graphene nanosheets (G) and pure, as well as doped Mg-, Mn-, V-Li4Ti5O12, spinel structure have been synthesized. As-prepared materials were characterized... 相似文献