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排序方式: 共有130条查询结果,搜索用时 453 毫秒
11.
Zahoor Ahmad Shazia Anjum Milan Skalicky Ejaz Ahmad Waraich Rana Muhammad Sabir Tariq Muhammad Ashar Ayub Akbar Hossain Mohamed M. Hassan Marian Brestic Mohammad Sohidul Islam Muhammad Habib-Ur-Rahman Allah Wasaya Muhammad Aamir Iqbal Ayman EL Sabagh 《Molecules (Basel, Switzerland)》2021,26(6)
Drought poses a serious threat to oilseed crops by lowering yield and crop failures under prolonged spells. A multi-year field investigation was conducted to enhance the drought tolerance in four genotypes of Camelina and canola by selenium (Se) application. The principal aim of the research was to optimize the crop yield by eliciting the physio-biochemical attributes by alleviating the adverse effects of drought stress. Both crops were cultivated under control (normal irrigation) and drought stress (skipping irrigation at stages i.e., vegetative and reproductive) conditions. Four different treatments of Se viz., seed priming with Se (75 μM), foliar application of Se (7.06 μM), foliar application of Se + Seed priming with Se (7.06 μM and 75 μM, respectively) and control (without Se), were implemented at the vegetative and reproductive stages of both crops. Sodium selenite (Na2SeO3), an inorganic compound was used as Se sources for both seed priming and foliar application. Data regarding physiochemical, antioxidants, and yield components were recorded as response variables at crop maturity. Results indicated that WP, OP, TP, proline, TSS, TFAA, TPr, TS, total chlorophyll contents, osmoprotectant (GB, anthocyanin, TPC, and flavonoids), antioxidants (APX, SOD, POD, and CAT), and yield components (number of branches per plant, thousand seed weight, seed, and biological yields were significantly improved by foliar Se + priming Se in both crops under drought stress. Moreover, this treatment was also helpful in boosting yield attributes under irrigated (non-stress) conditions. Camelina genotypes responded better to Se application as seed priming and foliar spray than canola for both years. It has concluded that Se application (either foliar or priming) can potentially alleviate adverse effects of drought stress in camelina and canola by eliciting various physio-biochemicals attributes under drought stress. Furthermore, Se application was also helpful for crop health under irrigated condition. 相似文献
12.
Riju Khandaker M. Kamruzzaman M. Afrose R. Rahman M. Khan M. K. R. Liton M. N. H. Helal M. A. Anam T. K. Rahman M. M. 《Crystallography Reports》2020,65(6):968-979
Crystallography Reports - Transition metals doped FeS2 thin films are promising materials for optoelectronics, energy saving and storage applications. This is a first time report on the... 相似文献
13.
López-Martín J Anam EM Boira H Sanz MJ Blázquez MA 《Chemical & pharmaceutical bulletin》2002,50(12):1613-1615
Dennettine, a new 2,6-dimethoxychromone and three known phenanthrene alkaloids (uvariopsine, stephenanthrine and argentinine) in addition to the phenolic and known compound vanillin were isolated from the roots of Dennettia tripetala. Their structures were determined by physical and spectroscopical one dimensional (1D) and 2D-NMR analysis, including heteronuclear multiple bond correlation and nuclear Overhauser enhancement spectroscopy. 相似文献
14.
A very rapid method for the separation of molybdenum(VI) from neutron irradiated uranium and its fission products is described. The procedure is based on the selective extraction of molybdenum(VI) by a 0.1M solution of 2-hexylpyridine in benzene from 4M HCl+0.04M KSCN. Decontamination factors were estimated to be >104 for the radionuclides of niobium, zirconium, ruthenium, lanthanum, cerium, promethium, yttrium, strontium and barium. 相似文献
15.
Nuzhat Jabeen Ejaz ur Rehman Shafaat Ahmed 《Journal of Radioanalytical and Nuclear Chemistry》2003,258(2):427-430
The isotopic composition of lithium in seawater has been determined by thermal ionization mass spectrometry (TIMS) based on the use of lithium hydroxide as the ion source. Isotopic measurements in a reference material supplied by IAEA (L-SVEC Li2CO3) were made to check the reproducibility of the method and 6Li indicates mobilization of light isotope of lithium form the sediment. 相似文献
16.
Muhammad Ejaz Bhanukiran Sunkara Lakhinder Kamboj Jibao He Vijay T. John Noshir S. Pesika Scott M. Grayson 《Journal of polymer science. Part A, Polymer chemistry》2013,51(15):3314-3322
An efficient and novel one‐pot process is developed to immobilize the atom transfer radical polymerization (ATRP) initiators onto the surface of fully pyrolyzed carbon hard spheres (CHSs) via a radical trapping process from the in situ thermal decomposition of bis(bromomethylbenzoyl)peroxide. The CHSs do not require any additional preparative treatment prior to the initiator immobilization. Styrene and methyl methacrylate are polymerized onto initiator‐immobilized CHSs by surface‐initiated atomic transfer radical polymerization (SI‐ATRP). Samples are characterized using Fourier transform infrared, thermogravimetric analysis, scanning electron microscopy, and transmission electron microscopy. These methods of characterization confirmed that all the CHSs are coated with a uniform layer of grafted polymer. This efficient, one‐pot immobilization of ATRP‐initiators represents an exceptionally simple route for the rapid preparation of various polymer‐coated carbon‐based nanomaterials using SI‐ATRP. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2013, 51, 3314–3322 相似文献
17.
Sana Moeez Ejaz Ahmad Siddiqui Shadab Khan Absar Ahmad 《Journal of Cluster Science》2017,28(4):1981-1993
In recent years, nanomaterials have made their way into hundreds of biomedical, life-sciences and technological applications. One such nanomaterial of extreme importance is nanoalumina (Al2O3 nanoparticles). This nanomaterial is an epitome of diversity with applications exhibited in the fields of catalysis, cosmetics, theranostics, energy generation, biosensors, drug-delivery, tumor-regression, etc. However, problems persist in terms of biocompatibility, cost-effectiveness, reproducibility and mass-production of nanoalumina by the presently existent physical, chemical and biological methodologies. Herein, we for the first time are presenting a top-down biofabrication method by which size reduction of commercial bulk alumina/aluminum oxide (5 µm) into nanoalumina (5–25 nm) is carried out by a thermophilic fungus Humicola sp. within 96 h of reaction at just 50 °C. The so-formed nanoalumina is highly stable, water dispersible, fluorescent and natural protein capped; characterization engaged standard techniques. These nanoparticles exhibit anti-bacterial properties against Gram-positive Bacillus subtilis strain and may serve as broad spectrum bactericidal agents. We believe that our novel top-down approach may be extensively used in the facile, inexpensive, eco-friendly and reliable fabrication of abundant quantities of nanomaterials of different chemical compositions, sizes and shapes with better control and predictability over the properties as derived from their substrates. The mechanistic aspect of said protocol is underway. 相似文献
18.
The extraction of technetium (VII) by 4-(5-nonyl)pyridine has been investigated from different aqueous solutions. Separation from uranium and some fission products has been achieved in nitrate media. From the results of partition experiments, attempts have been made to deduce the nature of the extracted species. 相似文献
19.
D. Mohammad T. Mahmood M. A. Qureshi M. Ejaz 《Journal of Radioanalytical and Nuclear Chemistry》1978,42(1):45-58
In an attempt to gain an understanding of factors affecting the extraction of iron(III) by 4-(5-nonyl)pyridine, the equilibria
between hydrogen chloride and benzene solutions of 4-(5-nonyl)pyridine have been studied. From acid distribution data and
visible absorption spectra of the organic phases, it was concluded that FeCl
4
−
ion, with a tetrahedral sp3 configuration is the principal iron containing species. The pyridine extraction of macro and trace amounts of the metal has
indicated the formation of 1∶1 and 2∶1 complexes respectively. The 2∶1 complexes are assumed to result from association of
a 1∶1 complex with a molecule of the pyridine hydrochloride. The salting-out effect increases in the order, LiCl<NaCl<MgCl2<AlCl3 and these differences in the effect have been attributed to the different degree of hydration of cations of the salts present
and to the ionic radii. The effect of various anions including the reducing agents have been described. Separation factors
of several metal ions relative to ferric iron, in 6M HCl, are also reported. 相似文献
20.