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Masoumeh Ghasempour Alireza Iranbakhsh Mostafa Ebadi Zahra Oraghi Ardebili 《等离子体物理论文集》2020,60(4):e201900159
The plasma-primed seeds of Catharanthus roseus were cultured in a hormone-free culture medium under sterile conditions. Plasma of 30 or 60 s improved root length (mean = 41.4%) and biomass (mean = 47%), whereas plasma of 90 s delayed plant growth. The plasma treatments enhanced concentrations of photosynthetic pigments and soluble phenols. Plasma of 90 s increased the proline level. With a similar trend, plasma priming induced activities of phenylalanine ammonia-lyase, catalase (about twofold) and peroxidase (31%) enzymes. Plasma also upregulated the expressions of deacetylvindoline O-acetyltransferase gene by an average of 7.8 times. Similarly, the plasma-treated seedlings contained higher concentrations of alkaloids (mean = 72%). Here, molecular evidence is provided on the plasma-associated modifications in secondary metabolism. 相似文献
13.
Structural Chemistry - Ab initio calculations have been performed to study the complexes between the noble gas elements (Ae = Ne, Ar, Kr) with a series of benzene isoelectronic heterocyclic... 相似文献
14.
Hossein Filian Alireza Kohzadian Masoud Mohammadi Arash Ghorbani-Choghamarani Amirali Karami 《应用有机金属化学》2020,34(6):e5579
In this research, a rapid, green and efficient protocol for synthesis of bis (pyrazolyl)methane derivatives in the presence of Pd(0)-guanidine@MCM-41 catalysts under solvent-free conditions by the following two methods has been reported: (i) via the one-pot pseudo five-component reaction among phenylhydrazine (2 equivalents), ethyl acetoacetate (2 equivalents) and aromatic aldehydes (1 equivalent); and (ii) the one-pot pseudo three-component reaction between 3-methyl-1-phenyl-1H-pyrazol-5(4H)-one (2 equivalents) and aromatic aldehydes (1 equivalent). Some advantages of this protocol include: green conditions, extremely short times, high efficiency, proper one-pot operation, generality of method, easy work-up and recyclability, and reusability of the catalyst up to five times without significant loss in catalytic activity. 相似文献
15.
More than 70% of the world's nickel reserves are found in laterite ores. In this research, a laterite ore sample, containing Ni, Co, and Fe, was employed to study the recovery of nickel and cobalt. Thus, the effect of calcination, acid concentration, percent solids, and stirring rate on nickel and cobalt recoveries from an iron-rich laterite sample was investigated. Optimization with response surface methodology and kinetic studies were performed. The calcination of the sample prior to leaching at 500°C for 2 h provided condition for better nickel and cobalt dissolutions. At optimal conditions, the concentration of sulfuric acid, solid-to-liquid ratio, stirring speed, temperature, and time test were equal to 5 M, 0.1, 370 rpm, 90°C, and 2 h, respectively. The highest recoveries of nickel and cobalt were 65.9% and 63.1%, respectively. Solids content had a negative effect on Ni and Co recovery, whereas acid concentration was positively affected. Addition of 10% (w/v) NaCl in the presence of 5 M acid concentration, 60°C, 370 rpm, and leaching time of 2 h increased the nickel and cobalt recoveries, 15.3% and 21.4%, respectively. The high dependence of process on temperature indicates chemical control; the activation energies Ea = 59.54 and Ea = 45.74 kJ/mol, respectively, for nickel and cobalt, were also consistent with this conclusion. 相似文献
16.
Najjar Morvarid Hosseini Hasan Ali Masoudi Abdolhossein Hashemzadeh Alireza Darroudi Majid 《Research on Chemical Intermediates》2020,46(4):2155-2168
Research on Chemical Intermediates - In this research, tin oxide nanoparticles (SnO2-nanoparticles) are synthesized using sol–gel method in polymeric bed and considering the principals of... 相似文献
17.
Prof. Allan J. Canty Prof. Alireza Ariafard Prof. Gerard van Koten 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(67):15629-15635
Density Functional Theory studies of square-planar PtII pincer structures, (4-Z-NCN)PtCl ([4-Z-NCN]−=[4-Z-2,6-(Me2NCH2)2C6H2-N,C,N]−, Z=H, NO2, CF3, CO2H, CHO, Cl, Br, I, F, SMe, SiMe3, tBu, OH, NH2, NMe2), enable characterisation of mesomerism for the pincer-Pt interaction. Relationships between Hammett σp substituent parameters of Z and DFT data obtained from NBO6 and AOMix computation are used to probe the interaction of the 5dyz orbital of platinum with π-orbitals of the arene ring. Analogous computation for 2,6-(Me2CH2)2C6H3Z (Z=H, CF3, CHO, Cl, Br, I, F, SMe, SiMe3, tBu, OH, NH2) and (4-H-NCN)PtZ allows an estimation of the relative substituent effects of “(CH2NMe2)2PtZ” on π-delocalisation in the pincer system. 相似文献
18.
Alireza Bandegi Kyungtae Kim Reza Foudazi 《Journal of polymer science. Part A, Polymer chemistry》2021,59(20):2334-2344
In this work, we investigate the effect of morphology and segmental dynamics on ion transport in polymerized lyotropic liquid crystals (polyLLCs) containing 1-butyl-3-methylimidazolium tetrafluoroborate as ionic liquid (IL). We demonstrate that two important factors, which affect ion conduction in polyLLCs, are grain size and chain density at the interface. The polyLLC with large grain size (70 nm) shows significant reduction in ion conductivity (one order of magnitude) compared to its homopolymer/IL mixture. However, the polyLLC with small grain size (20 nm) has little difference in ion conductivity compared to its homopolymer/IL mixture. It is observed that decreasing the chain density enhances the interaction of IL with polymer chains and consequently slows the relaxation of polymer chains. In addition, comparing the dynamics of polymer chains in mixtures of homopolymer/IL and templated LLC mesophases shows that the confinement in LLC structure prolongs the relaxation of polymer chains. 相似文献
19.
Zheng Yuanzhou Yang Haoran Mazaheri Hossein Aghaei Alireza Mokhtari Namjoo Afrand Masoud 《Journal of Thermal Analysis and Calorimetry》2021,143(2):1425-1438
Journal of Thermal Analysis and Calorimetry - The purpose of this study is to numerically investigate flow field and turbulent heat transfer of hybrid nanofluid, water–DWCNT–TiO2 in a... 相似文献
20.
Roushan Alireza Hassanjani Omrani Abdollah 《Journal of Thermal Analysis and Calorimetry》2021,144(1):107-118
Journal of Thermal Analysis and Calorimetry - This paper reports the successful synthesis of NaX nanocrystals using an organic, additive-free hydrothermal approach. Then, solution casting was used... 相似文献