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151.
Areeba Khayal Virendra Kumar Yadav Shivraj Gangadhar Wanale Krishna Kumar Yadav Abhishek Meena Mohd Shkir Zubair Ahmad Byong-Hun Jeon 《Particle & Particle Systems Characterization》2023,40(8):2300029
Nanotechnology applications are rapidly expanding in various fields because of its unique qualities, such as a large surface area. Also, the synthetic changes can be utilized to alter nanomaterial to fit into specialized necessities. From the last decade there is a tremendous increase in the utilization of nanotechnology and nanomaterials in the petroleum industry. The current review's main objective is to summarize numerous nanoparticle applications in the field of petroleum, bio-fuel formation, and clean-up treatments of oil spill-related issues with their existing challenges that may help improve further research. 相似文献
152.
Vikramdeep Monga Chhuttan Lal Meena Navneet Kaur Satyendra Kumar Chandrashekhar Pawar Shyam Sunder Sharma Rahul Jain 《Journal of heterocyclic chemistry》2008,45(6):1603-1608
153.
Jhajan Lal Gurudayal Prajapati Rachana Meena Ruchir Kant Dr. Ravi Sankar Ampapathi Dr. Damodara N. Reddy 《化学:亚洲杂志》2023,18(1):e202201023
We report herein the first systematic crystal structural investigation of azaproline incorporated in homo- and heterochiral diprolyl peptides. The X-ray crystallography data of peptides 1 – 5 illustrates that stereodynamic nitrogen in azaproline adopted the stereochemistry of neighbouring proline residue without depending on its position in the peptide sequence. Natural bond orbital analysis of crystal structures indicates OazPro−C′Pro of peptides 4 and 5 participating in n→π* interaction with stabilization energy about 1.21–1.33 kcal/mol. Density functional theory calculations suggested that the endo-proline ring puckering favoured over exo-conformation by 6.72–7.64 kcal/mol. NBO and DFT data reveals that the n→π* interactions and proline ring puckering stabilize azaproline chirality with the neighbouring proline stereochemistry. The CD, solvent titration, variable-temperature and 2D NMR experimental results further supported the crystal structures conformation. 相似文献
154.
Fundamental studies on the feasibility of deep eutectic solvents for the selective partition of glaucarubinone present in the roots of Simarouba glauca
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Faisal Kholiya Nidhi Bhatt Meena R. Rathod Ramavatar Meena Kamalesh Prasad 《Journal of separation science》2015,38(18):3170-3175
Several deep eutectic solvents prepared by the complexation of choline chloride as the hydrogen bond acceptor and hydrogen bond donors such as urea, thiourea, ethylene glycol, and glycerol were employed to partition glaucarubinone, an antimalarial compound present in roots of the plant, Simarouba glauca. Among all the solvents, the deep eutectic solvent consisting of the mixture of choline chloride and urea the most suitable to partition the antimalarial compound from the extract selectively. Analytical tools such as high‐performance liquid chromatography and electrospray ionization mass spectrometry were used for characterizations, and glaucarubinone extracted from the roots of the plant by conventional solvent extraction method was used as a reference for comparison. The hydrogen and noncovalent bonds formed between glaucarubinone and the deep eutectic solvents could be responsible for the selective partition of the drug molecule. 相似文献
155.
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157.
Bashir Ahmad Dar Nalini Pandey Snehil Singh R.K. Bamezai Meena Sharma Ram A. Vishwakarma Baldev Singh 《Tetrahedron letters》2014
Clay-supported heteropolyacid catalyst has been prepared and investigated as a novel heterogeneous, reusable and efficient catalyst for the one-pot synthesis of β-phosphonomalononitriles under ultrasound irradiation at room temperature. Compared with traditional methods, the present method is solvent-free, works under milder and cleaner conditions, furnishes products with higher purity and yields, needs shorter reaction time, easier work-up procedure, and generates less waste. No column purification is required and the products can be purified by simple crystallization. The catalyst can be easily recovered and reused several times without significant loss of its catalytic activity. The catalyst was characterized by scanning electron microscopy, X-ray powder diffraction, and thermal gravimetric, surface area, and elemental analyses. 相似文献
158.
Intergrowth perovskite type complex oxides of composition La1.2Sr1.8MnCrO7 and La1.5Sr1.5MnCrO7 have been synthesized by ceramic method. Rietveld profile analysis shows that the phases crystallize with tetragonal unit cell in the space group I4/mmm. Both the phases behave as insulators in the high temperature region and the linearity of log ρ versus T ?1/4 plot in the temperature range 150–300 K shows that the electronic conduction occurs by a 3D variable range hopping mechanism. The phases show insulator-metal transition at low temperature which could be due to the mixed valence state of Mn3+/Mn4+ by double exchange mechanism. The ferromagnetic interactions observed for the samples arises from double exchange interaction between Mn 3+ and Mn4+ and Cr3+ and Mn3+ ions. 相似文献
159.
Sumit Kumar Ramovatar Meena R. Paulraj 《Applied biochemistry and biotechnology》2016,180(7):1257-1275
Titanium-dioxide nanoparticles (TNP) are used in various consumable goods. Evidence has demonstrated the cytotoxicity of TNPs, but exact mechanism is yet to be elucidated. The present study has been aimed at finding out the mechanism of TNP-induced toxicity in biological system. Different doses of anatase-TNPs administrated intravenously to Wistar rats for once a week for 1 month and properties of TH cells, macrophages, cytokines secretion, oxidative damage, apoptotic pathway, and hematological and pathological changes were investigated as downstream events of TNP-mediated cytotoxicity. Result suggests that TNPs induce TH1 and TH2 response as measured by immunophenotyping (interferon gamma (IFN-γ) and interleukin (IL)-4) of TH cells, causing induction of M1 (nitric oxide (NO), nitric oxide synthase (iNOS), NF-kappaB (NF-κB), cyclooxygenase-2 (COX-2), IL-1, IL-6, and TNF-α) and M2 (Arg-1, Ym1) macrophages response. At lower dose, TH1 or M1 response counteracted by TH2 or M2 response, resulting in insignificant oxidative damage. However, with increasing dose of TNPs, the M1 response was increased over M2 response resulting in significant tissue damage. The M1-induced inflammatory response was found to cause DNA and chromosomal damage resulting apoptosis induction via upregulation of Bax/Bcl-2 ratio and subsequent loss of mitochondrial membrane potential and cyto c release in splenocytes. The TNP-led inflammatory response also causes damage at different tissue levels. 相似文献
160.
Mathematical modeling of the molar concentrations profile of ethanol, acetaldehyde and ethyl acetate inside the catalyst particle is presented. This kinetic mechanism is based on the system of non-linear reaction diffusion equations. Modified Adomian decomposition method is employed to derive the general analytical expressions of molar concentrations of ethanol, acetaldehyde and ethyl acetate for all possible values of the parameters Φi, γi and αi (i = 1, 2, 3). Analytical results are compared with the numerical results, a satisfactory agreement is noted. Valid and invalid region of the solution for all concentrations are provided. These analytical results are useful to understand the behavior of the system. 相似文献