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961.
Hamed Ahari Mostafa Fakhrabadipour Saeed Paidari Gulden Goksen Baojun Xu 《Molecules (Basel, Switzerland)》2022,27(22)
There is a worldwide concern about food loss due to reduced shelf life among food science researchers. Hence, it seems that any techniques contributing to improved food packaging are most welcome in the food sector. It has been demonstrated that the administration of nanotechnology-based techniques such as metal-based nanoparticles can fade away the unresolved obstacles in shortened shelf life and environmental concerns. Along with substantial signs of progress in nanoscience, there is a great interest in the usage of green synthesis-based methods for gold nanoparticles as the most advantageous metals, when compared to conventional chemistry-based methods. Interestingly, those aforementioned methods have significant potential to simplify targeted administration of gold nanoparticles due to a large surface-volume ratio, and diminished biohazards, aimed at increasing stability, and induction of anti-microbial or antioxidant properties. However, it is necessary to consider the hazards of gold nanoparticles including migration for food packaging purposes. 相似文献
962.
Umer Shahzad Hadi M. Marwani Mohsin Saeed Abdullah M. Asiri Md. Reazuddin Repon Raed H. Althomali Mohammed M. Rahman 《Chemical record (New York, N.Y.)》2024,24(1):e202300285
In recent years, a new class of highly crystalline advanced permeable materials covalent-organic frameworks (COFs) have garnered a great deal of attention thanks to their remarkable properties, such as their large surface area, highly ordered pores and channels, and controllable crystalline structures. The lower physical stability and electrical conductivity, however, prevent them from being widely used in applications like photocatalytic activities and innovative energy storage and conversion devices. For this reason, many studies have focused on finding ways to improve upon these interesting materials while also minimizing their drawbacks. This review article begins with a brief introduction to the history and major milestones of COFs development before moving on to a comprehensive exploration of the various synthesis methods and recent successes and signposts of their potential applications in carbon dioxide (CO2) sequestration, supercapacitors (SCs), lithium-ion batteries (LIBs), and hydrogen production (H2-energy). In conclusion, the difficulties and potential of future developing with highly efficient COFs ideas for photocatalytic as well as electrochemical energy storage applications are highlighted. 相似文献
963.
Aamer Saeed 《中国化学快报》2009,20(9):1073-1076
N-(4-Methyl-3-tolylthiazol-2(3H)-ylidene) substituted benzamides(2a-o) were synthesized in good to excellent yields by the base-catalyzed direct cyclization of corresponding 1-tolyl-3-aryl thioureas(1a-o) with 2-bromoacetone through microwave irradiation in a solvent-free medium.Compared to traditional thermal heating,microwave irradiation provides a much more cleaner,efficient and faster method for synthesis of the title compounds. 相似文献
964.
Golabchifar AA Rouini MR Shafaghi B Rezaee S Foroumadi A Khoshayand MR 《Talanta》2011,85(5):2320-2329
A simple, rapid and specific HPLC method has been developed and validated for the simultaneous determination of imatinib, a tyrosine kinase inhibitor, and its major metabolite, CGP74588, in human plasma. The optimization of the HPLC procedure involved several variables, of which the influences of each was studied. After a series of preliminary-screening experiments, the composition of the mobile phase and the pH of the added buffer solution were set as the investigated variables, while the resolution between imatinib and CGP74588 peaks, the retention time and the imatinib peak width were chosen as the dependent variables. Applying D-optimal design, the optimal chromatographic conditions for the separation were defined. The method proved to show good agreement between the experimental data and predictive values throughout the studied parameter range.The optimum assay conditions were achieved with a Chromolith™ Performance RP-8e 100 mm × 4.6 mm column and a mixture of methanol/acetonitrile/triethylamine/diammonium hydrogen phosphate (pH 6.25, 0.048 mol L−1) (20:20:0.1:59.9, v/v/v/v) as the mobile phase at a flow rate of 2 mL min−1 and detection wavelength of 261 nm. The run time was less than 5 min, which is much shorter than the previously optimized methods. The optimized method was validated according to FDA guidelines to confirm specificity, linearity, accuracy and precision. 相似文献
965.
Javid Hussain Nargis Jamila Farman Ullah Khan Krishna Prasad Devkota M. Raza Shah Saeed Anwar 《Magnetic resonance in chemistry : MRC》2009,47(7):625-627
One new tricyclic clerodane type diterpene aldehyde nepetanal (1) and one new benzene derivative nepetanoate (2) have been isolated from a plant Nepeta juncea together with two known compounds oleanolic acid (3) and ursolic acid (4). The structures of the isolated compounds were elucidated by means of modern spectroscopic techniques and comparison with literature data. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
966.
M. Saeed Arayne Najma Sultana M. Kamran Zaman 《Accreditation and quality assurance》2008,13(8):431-432
The concept of good manufacturing practice (GMP) is not new; its roots are very old. The incidents that gave birth to the
concept of GMP are summarized in this article. The journey from the FDA toward GMP is highlighted in chronological order.
These regulations are mandatory for pharmaceutical industries in order to manufacture quality products. 相似文献
967.
Saeed Salehi 《Mathematical Logic Quarterly》2003,49(3):316-322
It is shown that all the provably total functions of Basic Arithmetic BA, a theory introduced by Ruitenburg based on Predicate Basic Calculus, are primitive recursive. Along the proof a new kind of primitive recursive realizability to which BA is sound, is introduced. This realizability is similar to Kleene's recursive realizability, except that recursive functions are restricted to primitive recursives. 相似文献
968.
Masood Parvez Saeed Arayne Najma Sultana Ahsan Zamir Siddiqi 《Acta Crystallographica. Section C, Structural Chemistry》2004,60(4):o281-o283
The structure of the title compound, 1‐ethyl‐6‐fluoro‐1,4‐dihydro‐4‐oxo‐7‐(piperazin‐4‐ium‐1‐yl)‐1,8‐naphthyridine‐3‐carboxylate trihydrate, C15H17FN4O3·3H2O, has a zwitterion of enoxacin and three water molecules in the asymmetric unit. The zwitterions form sheets lying parallel to each other and are hydrogen bonded in a head‐to‐tail manner. The crystal structure is stabilized by the involvement of O and H atoms from all the water molecules in strong hydrogen bonds. The naphthyridine ring system is essentially planar, with the carboxylate group lying out of this plane at an angle of 26.13 (6)° and the ethyl group oriented at approximately right angles to this plane. The piperazinium ring adopts a chair conformation. 相似文献
969.
Glass fibers were characterized for physical and chemical changes before and after subjecting to aging under different environmental conditions. The conditions selected were: low temperature, outdoor atmosphere, indoor atmosphere, chemical environment, 95% humidity & water soaking treatment. The results show that glass fiber is a good candidate to resist sunlight, corrosive atmosphere, low temperature and shady atmosphere. The influence of prolonged time exposure to water caused a detrimental effect on the properties of the glass fiber. Hence, prolonged exposure to water should be avoided for the integrity of the glass fiber under study. 相似文献
970.
Two novel supramolecular complexes of types [Ru(L)(H2L)Cl·OH2] and [Ru(HLn)Cl3] (where H2L is a potential tetradentate ligand derived from hydrazine hydrate and diethyl malonate, and HLn is a potential bidentate ligand derived from coupling of allyl azo‐β‐diketone) have been synthesized and characterized by elemental analysis, conductance and magnetic measurements, followed by 1H NMR, to determine the effect of substituents on the intramolecular hydrogen bond. The electronic properties and models of the bonding of ligands and complexes were investigated by UV–Vis and IR spectroscopies. The first type of complex contains terminal hydrazinic nitrogen atoms with an unshared electron pair and may take part in nucleophilic condensations. Therefore, the reactions of allyl‐β‐diketone complexes with malonic dihydrazide have also been studied, as these cause ring closure and formation of supramolecular macrocyclic ligand complexes. The wavelengths of the principal electronic absorption peaks have been accounted for quantitatively in terms of crystal field theory, and various parameters have been evaluated. On the basis of the electronic spectra, an octahedral geometry has been established for the polymer complexes C. The macrocyclic polymer complexes D are pentacoordinate, and a trigonal‐bipyramidal environment (D3h) is suggested for the ruthenium(III) ion. The effect of the Hammett constant on the ligand field parameters is also discussed. Copyright © 2004 John Wiley & Sons, Ltd. 相似文献