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301.
Polyols obtained from seed oils have established themselves as excellent building blocks of polymers, viz. polyurethanes. In this work, a novel attempt has been made to incorporate boron in the backbone of polyol [LPO] derived from linseed oil. Furthermore, LPO was treated with phthalic anhydride [PA] and boric acid [BA] (in different molar ratios) to obtain boron incorporated linseed polyester polyols [BPPEs] through solvent less synthesis process. BPPEs were characterized by spectroscopic techniques (IR, 1H NMR and 13C NMR) to confirm the incorporation of boron and also to elucidate their structures. Physico-chemical characterization and antibacterial behavior of BPPEs was also investigated. It is speculated that these resins may serve as excellent raw materials for adhesives, coatings and as antibacterial agents. 相似文献
302.
合成了一个三羟基咔咯10-(4-羟基苯基)-5,15-双(4-(2-羟乙基)氨基-2,3,5,6-四氟苯基)咔咯(1)及其镓配合物(1-Ga)。光谱滴定实验、粘度测试和分子对接模拟结果表明,1和1-Ga通过外部结合模式与小牛胸腺DNA发生相互作用。琼脂糖凝胶电泳实验结果表明1和1-Ga显示出良好的光核酸酶活性。2种化合物对A549,HepG2,MCF-7肿瘤细胞有显著的光毒性。光辐照后,它们能通过活性氧物种(ROS)介导的线粒体途径诱导HepG2细胞凋亡。此外,1-Ga能使肿瘤细胞周期阻滞在G2/M期。 相似文献
303.
The longitudinal response functions are used to generalize the dispersion properties of electron acoustic waves (EAWs) in the presence of quantum recoil, for isotropic, non‐relativistic, degenerate/non‐degenerate plasmas. In order to study the EAWs, the constituents of non‐degenerate (thermal) plasma are considered to be of two groups of electrons having different number density and temperature, namely the cold electrons and the hot electrons. Similarly in degenerate (Fermi) plasma the two population of electrons are considered to be the thinly populated and the thickly populated electrons. The sparsely populated electrons are termed as cold electrons while the densely populated ones are termed as hot electrons. The ions are stationary which form the neutralizing background. The absorption coefficients for Landau damping with the inclusion of the quantum recoil in both plasmas are calculated and discussed. The results are discussed in the context of laser‐produced plasma. 相似文献
304.
Dr. Muhammad Mansha Asif Ayub Ibad Ali Khan Dr. Shahid Ali Dr. Atif Saeed Alzahrani Dr. Majad Khan Dr. Muhammad Arshad Dr. Abdul Rauf Dr. Safyan Akram Khan 《Chemical record (New York, N.Y.)》2024,24(1):e202300284
In recent years, aqueous organic redox flow batteries (AORFBs) have attracted considerable attention due to advancements in grid-level energy storage capacity research. These batteries offer remarkable benefits, including outstanding capacity retention, excellent cell performance, high energy density, and cost-effectiveness. The organic electrolytes in AORFBs exhibit adjustable redox potentials and tunable solubilities in water. Previously, various types of organic electrolytes, such as quinones, organometallic complexes, viologens, redox-active polymers, and organic salts, were extensively investigated for their electrochemical performance and stability. This study presents an overview of recently published novel organic electrolytes for AORFBs in acidic, alkaline, and neutral environments. Furthermore, it delves into the current status, challenges, and prospects of AORFBs, highlighting different strategies to overcome these challenges, with special emphasis placed on their design, composition, functionalities, and cost. A brief techno-economic analysis of various aqueous RFBs is also outlined, considering their potential scalability and integration with renewable energy systems. 相似文献
305.
The problem is considered of reconstructing a function in three-dimensional space from its integrals over a family of straight lines that are generators of cones, i.e., an inversion problem for the ray transform with incomplete data. This problem is connected with an auxiliary problem of analytic continuation and is strongly ill-posed. A uniqueness theorem and conditional stability estimates for a solution are obtained. 相似文献
306.
Ahmed Waqar Kazi S. N. Chowdhury Z. Z. Johan M. R. B. Akram Naveed Mujtaba M. A. Gul M. Oon C. S. 《Journal of Thermal Analysis and Calorimetry》2021,143(2):879-898
Journal of Thermal Analysis and Calorimetry - The thermophysical properties of freely suspended ZnO and TiO2 nanoparticles in a base fluid (DW) with different mass% concentrations of ZnO@TiO2/DW... 相似文献
307.
Journal of Thermal Analysis and Calorimetry - In the present article, importance of double-diffusivity convection in nanofluids on peristaltic pumping of Carreau fluid in tapered channel with... 相似文献
308.
Mosleh Mahmoud A. El-Hakim Elham H. Ahmed Anwar Z. El-Ghany Mohamed S. Abd El-Didamony Akram M. 《Journal of Radioanalytical and Nuclear Chemistry》2020,323(2):909-919
Journal of Radioanalytical and Nuclear Chemistry - Impregnation of tri-n-octylamine (TOA) into Siplite LX-16 resin, by two commonly used methods namely; wet and dry impregnation method, was studied... 相似文献
309.
Saba Hemmati Tara Zamenian Newsha Delsooz Akram Zangeneh Mohammad Mahdi Zangeneh 《应用有机金属化学》2020,34(2):e5274
Nanoparticles usually have better outcomes than the bulk samples of the same element because they possess a higher specificity level than the larger particles. This is also true for silver nanoparticles, and little amount of these materials has high remedial effects. Silver nanoparticles are used as a therapeutic tool for the treatment of several diseases such as cancer. In this study, silver nanoparticles using chitosan (AgNPs-chitosan composite) are reported for the first time to exert a dietary therapeutic potential compared to Daunorubicin in an animal model of acute myeloid leukemia. The synthesized AgNPs-chitosan composite was characterized using different techniques including ultraviolet–visible spectroscopy, fourier-transform infrared spectroscopy, energy dispersive X-ray spectrometry, scanning electron microscopy, and transmission electron microscopy. FTIR findings suggested antioxidant compounds in the nanoparticles were the sources of reducing power, reducing silver ions to AgNPs. SEM and TEM images exhibited a uniform spherical morphology and average diameters of 30 nm for the nanoparticles. Then, 1,1-diphenyl-2-picrylhydrazyl (DPPH) free radical scavenging test was done to evaluate the antioxidant potentials of Daunorubicin, AgNO3, chitosan, and AgNPs-chitosan composite. DPPH test revealed similar antioxidant potentials for Daunorubicin and AgNPs-chitosan composite. For the analyzing of cytotoxicity effects of Daunorubicin, AgNO3, chitosan, and AgNPs, 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromidefor (MTT) assay was used on HUVEC, 32D-FLT3-ITD, and Murine C1498 cell lines. AgNPs-chitosan composite similar to Daunorubicin had low cell viability dose-dependently against 32D-FLT3-ITD and Murine C1498 cell lines without any cytotoxicity on HUVEC cell line. In vivo design, induction of acute myeloid leukemia was done by 7,12-Dimethylbenz[a]anthracene in 50 mice. Then, the animals were randomly divided into six subgroups, including control, untreated, Daunorubicin, AgNO3, chitosan, and AgNPs-chitosan composite. Similar to Daunorubicin, AgNPs-chitosan composite significantly (P ≤ .01) decreased the weight of the body, the pro-inflammatory cytokines, and the total white blood cells, blast, neutrophil, monocyte, eosinophil, and basophil counts and increased the anti-inflammatory cytokines and the lymphocyte, platelet, and red blood cell parameters as compared to the untreated mice. These results show that the inclusion of chitosan improves the therapeutic properties of AgNPs-chitosan composite, which led to a significant enhancement in the antioxidant, cytotoxicity, and anti-acute myeloid leukemia activities of the nanoparticles. It appears that AgNPs-chitosan composite can be used as a chemotherapeutic drug for the treatment of acute myeloid leukemia in the clinical trial. 相似文献
310.
Ahmad Ahmeda Akram Zangeneh Roozbeh Javad Kalbasi Niloofar Seydi Mohammad Mahdi Zangeneh Sanaz Mansouri Samaneh Goorani Rohallah Moradi 《应用有机金属化学》2020,34(4):e5358
The purpose of this experiment was the green synthesis of silver nanoparticles from aqueous extracts of Ziziphora clinopodioides Lam (AgNPs@Ziziphora) and assessment of their cytotoxicity, antioxidant, antibacterial, antifungal, and cutaneous wound-healing effects. These nanoparticles were characterized using ultraviolet–visible spectroscopy (UV–Vis), X-ray diffraction (XRD), field emission scanning electron microscopy with energy-dispersive X-ray spectroscopy (FESEM-EDX), atomic force microscopy (AFM), and transmission electron microscopy (TEM). UV–Vis, TEM, and FESEM analyses indicated that the size of Ag nanoparticles (AgNPs) depended on Z. clinopodioides and AgNO3 concentrations. In vitro biological experiments indicated that AgNPs@Ziziphora has excellent antioxidant potential against DPPH, antifungal effects against Candida guilliermondii, Candida krusei, Candida glabrata, and Candida albicans, and antibacterial activities against Staphylococcus aureus, Bacillus subtilis, Streptococcus pneumonia, Salmonella typhimurium, Pseudomonas aeruginosa, and Escherichia coli O157:H7. Also, these nanoparticles did not exhibit cytotoxicity property against human umbilical vein endothelial cells (HUVECs). An in vivo biological test revealed that AgNPs@Ziziphora ointment significantly (p ≤ 0.01) increased the levels of wound contracture, blood vessels, hydroxyl proline, hexuronic acid, hexosamine, fibrocytes, fibroblasts, and fibrocyte/fibroblast ratio and significantly (p ≤ 0.01) decreased the wound area, and levels of total cells, neutrophils, and lymphocytes than other groups in rats. The results of UV–Vis, XRD, FESEM-EDX, AFM, and TEM confirmed that the aqueous extract of Z. clinopodioides can be used to produce silver nanoparticles with significant antioxidant, antimicrobial, and cutaneous wound-healing properties without any cytotoxicity. 相似文献