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81.
Journal of Thermal Analysis and Calorimetry - The increasing growth of helium consumption in industries and the limited resources of this element are the challenges that industries will face in the... 相似文献
82.
Ghorbani Bahram Mehrpooya Mehdi Aasadnia Majid 《Journal of Thermal Analysis and Calorimetry》2021,146(3):1255-1281
Journal of Thermal Analysis and Calorimetry - This work presents numerical simulation of two-dimensional thermogravitational energy transport in a chamber filled with copper–water ( $${\hbox... 相似文献
83.
Mustafa A. Jihad Farah T. M. Noori Majid S. Jabir Salim Albukhaty Faizah A. AlMalki Amal A. Alyamani 《Molecules (Basel, Switzerland)》2021,26(11)
Flaky graphene oxide (GO) nanoparticles (NPs) were synthesized using Hummer’s method and then capped with polyethylene glycol (PEG) by an esterification reaction, then loaded with Nigella sativa (N. sativa) seed extract. Aiming to investigate their potential use as a smart drug delivery system against Staphylococcus aureus and Escherichia coli, the spectral and structural characteristics of GO-PEG NPs were comprehensively analyzed by XRD, AFM, TEM, FTIR, and UV- Vis. XRD patterns revealed that GO-PEG had different crystalline structures and defects, as well as a higher interlayer spacing. AFM results showed GONPs with the main grain size of 24.41 nm, while GONPs–PEG revealed graphene oxide aggregation with the main grain size of 287.04 nm after loading N. sativa seed extract, which was verified by TEM examination. A strong OH bond appeared in FTIR spectra. Furthermore, UV- Vis absorbance peaks at (275, 284, 324, and 327) nm seemed to be correlated with GONPs, GO–PEG, N. sativa seed extract, and GO –PEG- N. sativa extract. The drug delivery system was observed to destroy the bacteria by permeating the bacterial nucleic acid and cytoplasmic membrane, resulting in the loss of cell wall integrity, nucleic acid damage, and increased cell-wall permeability. 相似文献
84.
Keypour Hassan Liyaghati-Delshad Mozhdeh Rezaeivala Maji Khavasi Hamid Reza 《无机化学学报》2014,30(7):1733-1740
在Mn髤模板作用下,2,6-diacetylpyridine(DAP)及合适链状胺化合物通过[1+1]环缩合反应,合成了3个大环席夫碱配合物,并进行了红外、元素分析、质谱及电导率等表征及研究。测得了配合物[MnL1(CH3CN)](ClO4)2的晶体结构,中心离子呈现出稍微扭曲的五角锥配位构型。研究了配合物对S.aureus(ATCC 6633),B.cereus(ATCC 7064),C.xerosis(ATCC 373)(gram-positive bacterial strains),E.coli(PTCC 10009),K.pneuomoniae(MTCC 109),and P.vulgaris(lio)(gram-negative bacterial strains)的抗菌活性。结果显示[MnL3](ClO4)2抗菌活性明显优于[MnL1(CH3CN)](ClO4)2and[MnL2](ClO4)2。在25℃条件下0.1 mol·L-1 KCl溶液中,通过电位计量法测定了化合物的质子化常数。 相似文献
85.
An facile and efficient protocol for the synthesis of 13‐aryl‐indeno[1,2‐b]naphtha[1,2‐e]pyran‐ 12(13H)‐ ones has been developed that proceeds via the one‐pot three‐component sequential reaction of an aromatic aldehyde with β‐naphthol and 2H‐indene‐1,3‐dione under solvent‐free conditions in the presence of a poly(4‐vinylpyridinium)hydrogen sulfate(P(4‐VPH)HSO4) catalyst. The catalyst can be reused several times, making this procedure facile, practical, and sustainable. The simple experimental procedure, solvent‐free reaction conditions, use of an inexpensive catalyst, short react time, and excellent yields are some of the major advantages of this methodology. 相似文献
86.
Hamed Rashidi Ali Ahmadpour Fatemeh F. Bamoharram Seyed Mojtaba Zebarjad Majid M. Heravi Faranak Tayari 《Chemical Papers》2014,68(4):516-524
ZnO nanostructures were synthesised in a hydrothermal reaction of zinc acetate in the presence of molybdophosphoric acid (H3[PMo12O40]) as well as its vanadium-substituted acid (H4[PMo11VO40]) at various times, temperatures, and concentrations. The ZnO nanostructures were characterised by X-ray diffraction, transmission electron microscopy, and Fourier transform infrared spectroscopy. The results demonstrated that the synthesised products are crystalline with a zincite hexagonal phase. Various ZnO nanostructures, such as nanoparticles, microrods, and nanosheets, were produced by changing the experimental conditions. The photocatalytic degradation of methyl orange was also investigated using the ZnO nanoparticles thus prepared. These particles exhibited high performance in the photocatalytic degradation of MO and almost 100 % decolourisation occurred within only 20 min. 相似文献
87.
Majid Ghashang Krishnamoorthy Aswin Syed Sheik Mansoor 《Research on Chemical Intermediates》2014,40(3):1135-1145
A facile and environmentally benign synthesis of some 2-amino-6-(2-oxo-2H-chromen-3-yl)-4-arylnicotinonitrile derivatives from the reaction of 3-acetylcoumarin, aromatic aldehydes, and malononitrile under solvent-free condition in the presence of silica-supported perchloric acid (HClO4–SiO2) is described. The ability to reuse the catalyst, the high yields, and ease of purification are the important features of this process. 相似文献
88.
Vahid Beigi-Somar Seyed Saied Homami Majid Ghazanfarpour-Darjani Amirhossein Monzavi 《Journal of heterocyclic chemistry》2020,57(1):140-150
In situ generated copper acetylides react with isocyanates and oxiranes to form a decent range of morpholine derivatives. The reactions proceeded with acceptable yields and excellent regioselectivity. The presence of oxygen and moisture completely inhibited the reaction. The scope of the reaction is wide and the reactions involve consecutive C–C, C–N, and C–O bond formations. 相似文献
89.
A novel biochar-based graphitic carbon nitride was prepared through calcination of Zinnia grandiflora petals and urea. To provide acidic and ionic-liquid functionalities on the prepared carbon, the resultant biochar-based graphitic carbon nitride was vinyl functionalized and polymerized with 2-acrylamido-2-methyl-1-propanesulfonic acid, acrylic acid and the as-prepared 1-vinyl-3-butylimidazolium chloride. The final catalytic system that benefits from both acidic (–COOH and –SO3H) and ionic-liquid functionalities was applied as a versatile, metal-free catalyst for promoting some model acid catalyzed reactions such as Knoevenagel condensation and Biginelli reaction in aqueous media under a very mild reaction condition. The results confirmed high activity of the catalyst. Broad substrate scope and recyclability and stability of the catalyst were other merits of the developed protocols. Comparative experiments also indicated that both acidic and ionic-liquid functionalities on the catalyst participated in the catalysis. 相似文献
90.
Hosseinikhah Seyed Mahdi Beigzadeh Borhan Siavashi Majid Halabian Mahdi 《Journal of Thermal Analysis and Calorimetry》2020,141(5):1543-1558
Journal of Thermal Analysis and Calorimetry - High interstitial fluid pressure in the tumor is among the most important barriers to drug delivery. The use of the static magnetic field is one of the... 相似文献