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1.
Russian Journal of General Chemistry - In this paper, two new complexes of selenium caffeine, [Se(Caf)4], and zinc α-tocopherol, [Zn(α-Tpl)2(NO3)2], are synthesized. The structures of...  相似文献   
2.
Image segmentation is a fundamental but essential step in image processing because it dramatically influences posterior image analysis. Multilevel thresholding image segmentation is one of the most popular image segmentation techniques, and many researchers have used meta-heuristic optimization algorithms (MAs) to determine the threshold values. However, MAs have some defects; for example, they are prone to stagnate in local optimal and slow convergence speed. This paper proposes an enhanced slime mould algorithm for global optimization and multilevel thresholding image segmentation, namely ESMA. First, the Levy flight method is used to improve the exploration ability of SMA. Second, quasi opposition-based learning is introduced to enhance the exploitation ability and balance the exploration and exploitation. Then, the superiority of the proposed work ESMA is confirmed concerning the 23 benchmark functions. Afterward, the ESMA is applied in multilevel thresholding image segmentation using minimum cross-entropy as the fitness function. We select eight greyscale images as the benchmark images for testing and compare them with the other classical and state-of-the-art algorithms. Meanwhile, the experimental metrics include the average fitness (mean), standard deviation (Std), peak signal to noise ratio (PSNR), structure similarity index (SSIM), feature similarity index (FSIM), and Wilcoxon rank-sum test, which is utilized to evaluate the quality of segmentation. Experimental results demonstrated that ESMA is superior to other algorithms and can provide higher segmentation accuracy.  相似文献   
3.
The impact of the charge transfer complex on the dielectric relaxation processes in free poly(methyl methacrylate) (PMMA) polymer sheets was investigated. The frequency dependence of dielectric properties was obtained over the frequency range 0.1 Hz–1 MHz at temperatures ranging between 303 K and 373 K for perylene dye and acceptors (picric acid (PA) and chloranilic acid (CLA)) in an in situ PMMA polymer. The TG/dTG technique was used to investigate the thermal degradation of the synthesized polymeric sheets. Additionally, the kinetic parameters have been assessed using the Coats–Redfern relation. The dielectric relaxation spectroscopy of the synthesized polymeric sheets was analyzed in terms of complex dielectric constant, dielectric loss, electrical modulus, electrical conductivity, and Cole–Cole impedance spectroscopy. α- and β-relaxation processes were detected and discussed. The σ(ω) dispersion curves of the synthesized polymeric sheets show two distinct regions with increasing frequency. The impedance data of the synthesized polymeric sheets can be represented by the equivalent circuit (parallel RC).  相似文献   
4.
Russian Journal of General Chemistry - Transition metals such as Cr(III), Mn(II), Fe(III), Co(II), Ni(II), Zn(II), Cd(II), and Hg(II) have been reacted with gibberellic acid (HGA) to give novel...  相似文献   
5.
Considering oxatriazino[a]isoindole as a wealthy structure for developing molecules of impressive therapeutic potentials, some new oxatriazino[3,2‐a]isoindoles analogs were synthesized. Thus, 3‐mercapto‐6H‐[1,2,4,5]oxatriazino[3,2‐a]isoindol‐6‐one ( 5 ), was prepared as one‐pot three‐components product and subjected to a series of manipulations including cycloaddition reactions to annulate a series of pharmacophoric motif conjugates. The structures of the newly synthesized compounds were elucidated based on their correct elemental and spectroscopic data.  相似文献   
6.
The potential benefit of selenium nanoparticles (SeNPs) and vitamin E (Vit.E) that they are potent antioxidants , they were used as antioxidants against acrylamide (ACR) hepatotoxicity, ACR is found in the starchy foods that had been heated for long periods in high degrees above 120°C. So the aim of the current study was to elucidate the antihyperlipidemic and hepatoprotective effects of either SeNPs and/or Vit.E against ACR toxicity, SeNPs were characterized by SEM, EDX, TEM and they proved their spherical nanostructure. Zeta potential value was –22.9 mv with particle size with a diameter range (48.75-67.24 nm) which proved the high stability of the used SeNPs. Seven groups of male mice were used: group I was control,group II ACR,group III was treated with SeNPs, IV group was received Vit.E and groups V,VI received ACR plus SeNPs and ACR plus Vit.E, group VII was given combination of SeNPs and Vit.E plus ACR,So,The effect of SeNPs and/or Vit.E were monitored against ACR hepatotoxicity and hyperlipidemia. ACR administration afforded significant elevation in the hepatic enzymes with severe alterations in the lipid metabolism. These findings clarified the efficacy of SeNPs and Vit.E by declining the high hepatic enzymes activities induced by ACR along with improving the lipid profile, elevation of the antioxidant enzymes (SOD,CAT and GRx), reduction of MDA level, improving histological and ultrastructutral hepatic tissues and restoration of most normal structures that were damaged in ACR group. So, SeNPs and/or Vit.E were proved to enhance the hepatic antioxidant capacities.  相似文献   
7.
Series of Co (II), Cu (II), Zn (II) and Sn (II) complexes derived from thiosemicarbazide ligand (HTSC), was synthesized by environmentally favorable method (electrochemical). All isolated complexes, were deliberately characterized by available analytical and spectral tools. The proposed molar ratio was 1:2 (M:L) as the only isolated one, beside the significant contribution for solvent molecules. The octahedral configuration was proposed for all complexes. Conformational analysis was implemented using advanced program to determine the best structural forms for complexes. Moreover, essential parameters were calculated to export important features for studied complexes. Meanwhile, Hirshfeld crystal surface properties, were interested to illustrate strength of packing interaction forces. Furthermore, distinction of site types inside the molecule and their H-donor or H-acceptor ability. Antimicrobial study was conducted against different microorganisms, to assert on the importance of new complexes in therapeutic field. Furthermore and to strengthen the study, the inhibition simulation was performed with respect to all complexes against selected pathogen proteins. Essential interaction data, were exported for each docking process, to classify inhibition efficiency. Co (II) and Cu (II) complexes were the complexes that played well in therapeutic simulation treatments against Bacillus subtilis (1bn8) and Candida albicans kinase (4c0t) proteins.  相似文献   
8.
In our approach to synthesize bioactive molecules, a series of novel N‐heterocycles were synthesized and evaluated for their in vitro antitumor activity against a panel of three human cancer cell lines, namely, human breast cancer cell line (MCF‐7), human cervical cancer cell line (HeLa), and human prostate cancer PC‐3. The majority of the tested compounds exhibited significant cytotoxic activity toward the tested tumor cell lines. Analogues 33 , 34 , 31 , 38 , 21 , 23 , 22 , and 20 exhibited considerable cytotoxic activities comparable with standard drug 5‐fuorouracil. Compound 33 displayed superior cytotoxicity with IC50 value of 4.12 ± 1.21 μg/mL against HeLa tumor cell line.  相似文献   
9.
Various novel benzimidazole entities linked to pyrazolyl and hydrazonoyl cyanide substrates carrying aryl and heteroaryl groups ( 8a – e to 10a – e ) were synthesized using new route syntheses and were focused on their pharmacological evaluation as one of the most important factors for the determination of the activity of these synthesized compounds. The obtained benzimidazoles' series were fully characterized and exhibited remarkable pharmacological activity upon in vitro screening for their antibacterial activity against strains of selected pathogenic Gram‐positive bacteria (Staphylococcus aureus) and Gram‐negative bacteria (Escherichia coli) comparing with Ampicillin and Kanamycin as standard antibacterial agents and against human liver cancer cell lines (HepG2) as antitumor agents as well.  相似文献   
10.
The utilization of fermented foods with health-promoting properties is becoming more popular around the world. Consequently, kefir, a fermented milk beverage made from kefir grains, was shown in numerous studies to be a probiotic product providing significant health benefits. Herein, we assessed the antibacterial and antifungal potential of kefir against a variety of pathogenic bacteria and fungi. This study also showed the effectiveness of kefir in healing wounds in human gastric epithelial cells (GES-1) by (80.78%) compared with control (55.75%) within 48 h. The quantitative polymerase chain reaction (qPCR) results of kefir-treated HCV- or HBV- infected cells found that 200 µg/mL of kefir can eliminate 92.36% of HCV and 75.71% of HBV relative to the untreated infected cells, whereas 800 µg/mL (the highest concentration) completely eradicated HCV and HBV. Moreover, the estimated IC50 values of kefir, at which HCV and HBV were eradicated by 50%, were 63.84 ± 5.81 µg/mL and 224.02 ± 14.36 µg/mL, correspondingly. Kefir can significantly suppress the elevation of TNF-α and upregulate IL-10 and INF-γ in both treated HCV- and HBV-infected cells. High-performance liquid chromatography (HPLC) and gas chromatography-mass spectrometry (GC-MS) analysis of kefir revealed the presence of numerous active metabolites which mainly contribute to the antimicrobial, antiviral, and immunomodulatory activities. This study demonstrated, for the first time, the anti-HBV efficacy of kefir while also illustrating the immunomodulatory impact in the treated HBV-infected cells. Accordingly, kefir represents a potent antiviral agent against both viral hepatitis C and B, as well as having antimicrobial and wound healing potential.  相似文献   
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