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41.

In today’s era, a fascinating discipline is immensely influencing a wide miscellany in different fields of science and technology known as quantum cryptography. The amalgamation of different unconventional themes of information security and fast computing have appended inventiveness and creativity into the performance of quantum systems which exhibits astonishing outcomes surprisingly for the most complicated nonlinear models. The exploitation of chaos theory at quantum scale is a dynamical new approach towards the system of information security. Regarding this a novel image encryption approach based on modern standards of chaos, fast computing and quantum encryption has been proposed in this article. In the designed scheme, Walsh transformation is exploited to get standard image compression as to reduce data being processed resulting in fast computing. Quantum spinning and rotation operators leading new protocols, compressed data is encrypted using quantum spinning and rotation operators. For adding more confusion capability in contemplated algorithm discrete fractional chaotic Lorenz system is also accomplished. The proposed system has been validated through statistical analysis, the assessments accordingly by statistical analysis tests clearly emphasis that proposed scheme of encryption is comparatively equitable for the digital images security.

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42.
The article studies the application of the extended Fan sub-equation method to \((1+1)\)-dimensional nonlinear dispersive modified Benjamin-Bona-Mahony equation with fractional evolution. This equation describes the hydromagnetic waves in cold plasma, acoustic waves in inharmonic crystals and acoustic gravity waves in compressible fluids. The structure of the extended Fan sub-equation method on the basis of time-fractional derivative is presented. The main idea of the method is to take full advantage of the general elliptic equation involving five parameters. The fractional derivatives are taken as in the sense of Jumarie’s modified Riemann–Liouville derivative. The method is reliable and gives more general exact solutions than the existing methods.  相似文献   
43.
Irshad  M.  Ali  Q.  Iram  F.  Ahmad  S. A.  Saleem  M.  Saadia  M.  Batool  M.  Kanwal  A.  Tabassum  S. 《Russian Journal of General Chemistry》2019,89(8):1734-1734
Russian Journal of General Chemistry - The fourth author of the article should read S. A. Ahmadaa.  相似文献   
44.
    
2‐Aminothiazole is a valuable synthon in organic synthesis and an important structural unit of pharmaceutically active drugs. It is accessible via several synthetic routes. In the current account, compound 4 {4‐(4‐bromophenyl) thiazol‐2‐amine} was synthesized by employing a recently reported procedure of Gabriel synthesis using Lawesson reagent. The title compound was characterized through spectro‐elemental analytical data, and its crystal structure was determined by single‐crystal X‐ray diffraction. The torsion angles, bond lengths, and bond strengths between the planes of the thiazole and phenyl rings were optimized by theoretical calculations by applying the B3LYP/6‐311++G(d,p) level for the purpose of investigating the conformational effects on the stabilization of the crystal packing. HOMO‐LUMO analysis, vibrational analysis, and thermodynamic parameters were also investigated. A detailed analysis of the intermolecular interactions of thiazole moiety bearing the amino and bromophenyl ring has been performed based on the Hirshfeld surfaces and their associated two‐dimensional fingerprint plots. The relative contributions of the main intermolecular contacts as well as the enrichment ratios derived from the Hirshfeld surface analysis establish the 2‐aminothiazole synthon to be a molecule of great interest. DNA binding studies pointed towards anticancer potency of the synthesized compound via reversible binding.  相似文献   
45.
The syntheses, characterization, and crystal structures of the reaction products of Cu2+ with imidazole (Himz) and different aromatic carboxylates, viz.: [Cu(Himz)2(cinn)2(H2O)] (1), [Cu(Himz)2(paba)2] (2) and [Cu(Himz)2(clba)2] (3) (cinn = C9H7O2, paba = C7H6NO2, clba = C7H4ClO2) are described and studied by spectroscopic (UV–visible, FTIR) measurements. Single-crystal X-ray diffraction analyses indicate that each complex is monomeric. The metal ion in 1 adopts square-pyramidal coordination geometry arising from two imidazole nitrogens, two cinnamate oxygens, and an apical aqua. The metal ions of 2 and 3, however, assume a square planar configuration, which is realized by coordination of two nitrogens of two imidazoles and two oxygens; in both complexes, the imidazole moieties are trans to each other. TGA results indicate that upon heating, these complexes lose their carboxylate anions first, followed by removal of the imidazole molecules.  相似文献   
46.
    
Efficiently generating C1 building blocks from environmentally friendly carbon sources, such as through photocatalytic CO2 reduction, is essential for fostering a sustainable circular economy. The pursuit of mild catalytic activation methods has yielded powerful catalysts that can be synergistically employed alongside various reaction media to enhance overall performance. Herein, we elucidate the influence of diverse imidazolium-based ionic liquids as additives for visible-light-driven CO2 reduction with ruthenium(II)- and rhenium(I)-bipyridine complexes. Our investigation reveals that incorporating ionic liquids into traditional solvents at concentrations below 10 % can markedly boost CO production while suppressing H2 generation. The best results were obtained for the highly basic ionic liquid [C2mim][OAc], resulting in a substantial rise in CO formation from 0.3 μmol/h to 5.4 μmol/h and an increase in turnover number from 3 to 59. This study underscores the cooperative influence of imidazolium-based ionic liquids on CO2 photoreduction while circumventing their use as primary solvents, thus offering a promising avenue for sustainable chemical synthesis.  相似文献   
47.
    
This study examines entropy generation in the peristaltic flow of Johnson–Segalman fluid through a curved channel, considering the effects of Hall and ion slip due to an externally applied magnetic field and activation energy. The fluid dynamics are modeled using a highly nonlinear mathematical framework, which is non-dimensionalized and simplified with a lubrication approach. Numerical solutions are obtained using the shooting technique to analyze fluid flow properties. The results, presented graphically, provide a comprehensive understanding of the interactions between the non-Newtonian characteristics of the Johnson–Segalman fluid, entropy generation, and activation energy effects. The study finds that increasing the Hall parameter enhances entropy generation. Higher activation energy increases the rate of chemical reactions and by-products, raising system randomness. Additionally, reducing the channel curvature or increasing the curvature parameter elevates the system's entropy. These insights are valuable for biomedical and industrial applications.  相似文献   
48.
    
Fagonia indica is a rich source of pharmacologically active compounds. The variation in the metabolites of interest is one of the major issues in wild plants due to different environmental factors. The addition of chemical elicitors is one of the effective strategies to trigger the biosynthetic pathways for the release of a higher quantity of bioactive compounds. Therefore, this study was designed to investigate the effects of chemical elicitors, aluminum chloride (AlCl3) and cadmium chloride (CdCl2), on the biosynthesis of secondary metabolites, biomass, and the antioxidant system in callus cultures of F. indica. Among various treatments applied, AlCl3 (0.1 mM concentration) improved the highest in biomass accumulation (fresh weight (FW): 404.72 g/L) as compared to the control (FW: 269.85 g/L). The exposure of cultures to AlCl3 (0.01 mM) enhanced the accumulation of secondary metabolites, and the total phenolic contents (TPCs: 7.74 mg/g DW) and total flavonoid contents (TFCs: 1.07 mg/g DW) were higher than those of cultures exposed to CdCl2 (0.01 mM) with content levels (TPC: 5.60 and TFC: 0.97 mg/g) as compared to the control (TPC: 4.16 and TFC: 0.42 mg/g DW). Likewise, AlCl3 and CdCl2 also promoted the free radical scavenging activity (FRSA; 89.4% and 90%, respectively) at a concentration of 0.01 mM, as compared to the control (65.48%). For instance, the quantification of metabolites via high-performance liquid chromatography (HPLC) revealed an optimum production of myricetin (1.20 mg/g), apigenin (0.83 mg/g), isorhamnetin (0.70 mg/g), and kaempferol (0.64 mg/g). Cultures grown in the presence of AlCl3 triggered higher quantities of secondary metabolites than those grown in the presence of CdCl2 (0.79, 0.74, 0.57, and 0.67 mg/g). Moreover, AlCl3 at 0.1 mM enhanced the biosynthesis of superoxide dismutase (SOD: 0.08 nM/min/mg-FW) and peroxidase enzymes (POD: 2.37 nM/min/mg-FW), while CdCl2 resulted in an SOD activity up to 0.06 nM/min/mg-FW and POD: 2.72 nM/min/mg-FW. From these results, it is clear that AlCl3 is a better elicitor in terms of a higher and uniform productivity of biomass, secondary cell products, and antioxidant enzymes compared to CdCl2 and the control. It is possible to scale the current strategy to a bioreactor for a higher productivity of metabolites of interest for various pharmaceutical industries.  相似文献   
49.
Microbial hydroxylation of pregnenolone derivatives   总被引:1,自引:0,他引:1  
Pregnenolone and pregnenolone acetate were incubated with the fungi Cunninghamella elegans, Rhizopus stolonifer and Gibberella fujikuroi. Incubation of with C. elegans yielded metabolites, 3beta,7beta,11alpha-trihydroxypreg-5-en-20-one, 3beta,6alpha,11alpha,12beta,15beta-pentahydroxypreg-4-en-20-one and 3beta,6beta,11alpha-trihydroxypreg-4-en-20-one, while incubation with G. fujikuroi yielded two known metabolites, 3beta,7beta-dihydroxypregn-5-en-20-one and 6beta,15beta-dihydroxypreg-4-ene-3,20-dione. Metabolites and were found to be new. Fermentation of by C. elegans yielded four known oxidative metabolites, androsta-1,4-diene-3,17-dione, 6beta,15beta-dihydroxyandrost-4-ene-3,17-dione and 11alpha,15beta-dihydroxypreg-4-ene-3,20-dione. Fermentation of with R. stolonifer yielded two known metabolites, 11alpha-hydroxypreg-4-ene-3,20-dione and. Compounds were screened for their cholinesterase inhibitory activity in a mechanism-based assay.  相似文献   
50.
    
A simple, efficient and eco‐friendly procedure has been developed using Cu(II) immobilized on guanidinated epibromohydrin‐functionalized γ‐Fe2O3@TiO2 (γ‐Fe2O3@TiO2‐EG‐Cu(II)) for the synthesis of 2,4,5‐trisubstituted and 1,2,4,5‐tetrasubstituted imidazoles, via the condensation reactions of various aldehydes with benzil and ammonium acetate or ammonium acetate and amines, under solvent‐free conditions. High‐resolution transmission electron microscopy analysis of this catalyst clearly affirmed the formation of a γ‐Fe2O3 core and a TiO2 shell, with mean sizes of about 10–20 and 5–10 nm, respectively. These data were in very good agreement with X‐ray crystallographic measurements (13 and 7 nm). Moreover, magnetization measurements revealed that both γ‐Fe2O3@TiO2 and γ‐Fe2O3@TiO2‐EG‐Cu(II) had superparamagnetic behaviour with saturation magnetization of 23.79 and 22.12 emu g?1, respectively. γ‐Fe2O3@TiO2‐EG‐Cu(II) was found to be a green and highly efficient nanocatalyst, which could be easily handled, recovered and reused several times without significant loss of its activity. The scope of the presented methodology is quite broad; a variety of aldehydes as well as amines have been shown to be viable substrates. A mechanism for the cyclocondensation reaction has also been proposed.  相似文献   
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