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501.
We consider the zero-temperature single-spin-flip dynamics of the random-field Ising model on a Bethe lattice in the presence of an external field h. We derive the exact self-consistent equations to determine the distribution Prob(s) of avalanche sizes s as the external field increases from – to . We solve these equations explicitly for a rectangular distribution of the random fields for a linear chain and the Bethe lattice of coordination number z=3, and show that in these cases, Prob(s) decreases exponentially with s for large s for all h on the hysteresis loop. We find that for z4 and for small disorder, the magnetization shows a first-order discontinuity for several continuous and unimodal distributions of the random fields. The avalanche distribution Prob(s) varies as s
–3/2 for large s near the discontinuity. 相似文献
502.
Janjic JM Srinivas M Kadayakkara DK Ahrens ET 《Journal of the American Chemical Society》2008,130(9):2832-2841
We report the design, synthesis, and biological testing of highly stable, nontoxic perfluoropolyether (PFPE) nanoemulsions for dual 19F MRI-fluorescence detection. A linear PFPE polymer was covalently conjugated to common fluorescent dyes (FITC, Alexa647 and BODIPy-TR), mixed with pluronic F68 and linear polyethyleneimine (PEI), and emulsified by microfluidization. Prepared nanoemulsions (<200 nm) were readily taken up by both phagocytic and non-phagocytic cells in vitro after a short (approximately 3 h) co-incubation. Following cell administration in vivo, 19F MRI selectively visualizes cell migration. Exemplary in vivo MRI images are presented of T cells labeled with a dual-mode nanoemulsion in a BALB/c mouse. Fluorescence detection enables fluorescent microscopy and FACS analysis of labeled cells, as demonstrated in several immune cell types including Jurkat cells, primary T cells and dendritic cells. The intracellular fluorescence signal is directly proportional to the 19F NMR signal and can be used to calibrate cell loading in vitro. 相似文献
503.
Uday C. Mashelkar Deepak M. Rane Rajesh S. Kenny 《Journal of heterocyclic chemistry》2008,45(3):865-872
504.
Alka Patle Ramsingh Kurrey Manas Kanti Deb Tarun Kumar Patle Deepak Sinha Kamlesh Shrivas 《印度化学会志》2022,99(9):100545
Heavy metals are a group of metals and metalloids that have relatively high density and are toxic even at ppb levels. The excess intake of heavy metals in human bodies though the environment may cause various humans health problems. Analytical approaches of some selected toxic heavy metals in the environment and their socio-environmental impacts are discussed in this review. In this present investigation, we have also discussed the design and development of nanomaterials for the detection of metal ions along with kinetic approaches. The isolation or pre-concentration and determination of heavy metals from complex matrices become challenging for analytical chemists and researchers. The fundamentals on sample preparation and analysis of some selected heavy metals employing different analytical tools for qualitative and quantitative determination of these pollutants in real samples are also discussed. In addition, this compiled work enhanced our knowledge in learning about pathway mechanisms and the degree of their risk assessment. 相似文献
505.
Kalimuthu K Suresh Babu R Venkataraman D Bilal M Gurunathan S 《Colloids and surfaces. B, Biointerfaces》2008,66(1):150-153
The use of microorganisms for the synthesis of nanoparticles is in the limelight of modern nanotechnology. Using the bacterium Bacillus licheniformis, the biosynthesis of silver nanoparticles was investigated. These silver nanoparticles were characterized by means of UV-vis spectroscopy, scanning electron microscopy (SEM), electron diffraction spectroscopy (EDX) and X-ray diffraction (XRD). The nanoparticles exhibited maximum absorbance at 440 nm in UV-vis spectroscopy. The XRD spectrum of silver nanoparticles exhibited 2theta values corresponding to the silver nanocrystal. SEM micrographs revealed the formation of well-dispersed silver nanoparticles of 50 nm, and the presence of silver was confirmed by EDX analysis. 相似文献
506.
Shivaji S. Pawar Deepak V. Dekhane Murlidhar S. Shingare Shivaji N. Thore 《中国化学快报》2008,19(9):1055-1058
Glyoxylic acid (5 mol%) performs as a novel highly water-soluble catalyst for the synthesis of 2-aryl-l-arylmethyl-lH- benzimidazoles from a wide range of substituted o-phenylenediamines and various substituted aldehydes in good to excellent isolated yields (85-95%) using water as solvent at ambient temperature. The remarkable advantages offered by this method are easily and inexpensive available catalyst, simple procedure, mild conditions, much faster (20--40 rain) reactions and excellent yields of products. 相似文献
507.
Ibrahim Ahmed Shaikh Uday M. Muddapur Zabin K. Bagewadi Sneha Chiniwal Mohammed M. Ghoneim Mater H. Mahnashi Fahad Alsaikhan Deepak Yaraguppi Francois N. Niyonzima Sunil S. More Basheerahmed Abdulaziz Mannasaheb Amer Al Ali Abdulaziz Asiri Aejaz Abdullatif Khan S. M. Shakeel Iqubal 《Molecules (Basel, Switzerland)》2022,27(9)
The applications of bioactive compounds from medicinal plants as therapeutic drugs are largely increasing. The present study selected the bioactive compounds from Acacia concinna (A. concinna) and Citrus limon (C. limon) to assess their phytochemicals, proteins, and biological activity. The plant material was collected, and extraction performed as per the standard procedure. Qualitative analysis was undertaken, and identification of functional organic groups was performed by FTIR and HPLC. Antibacterial, anticancer, antioxidant, antihyperglycemic, antihyperlipidemic, and inhibition kinetics studies for enzymes were performed to assess the different biological activities. Flavonoids and phenols were present in a significant amount in both the selected plants. A. concinna showed significant antimicrobial activity against Z. mobilis, E. coli, and S. aureus, with minimum inhibition zones (MIZ) of 24, 22, and 20 mm, respectively. C. limon strongly inhibited all the tested pathogenic bacteria with maximum and minimum MIZ of 32 and 17 mm. A. concinna silver nanoparticles also exhibited potent antimicrobial activity. Both extracts showed substantial antioxidant, antihyperlipidemic, antidiabetic, anticancer (MCF-7), and anti-urease (antiulcer) properties. To conclude, these plants can be used to treat hyperlipidemia, diabetes, cancer, and gastrointestinal ulcers. They can also serve as antimicrobial and antioxidant agents. Thus, the studied plants must be exploited cost-effectively to generate therapeutic drugs for various diseases. 相似文献
508.
Arpitha Badarinath Mahajanakatti Telugu Seetharam Deepak Raghu Ram Achar Sushma Pradeep Shashanka K Prasad Rajeswari Narayanappa Deepthi Bhaskar Sushravya Shetty Govindappa Melappa Lavanya Chandramouli Sanjukta Mazumdar Ekaterina Silina Victor Stupin Chandrashekar Srinivasa Chandan Shivamallu Shiva Prasad Kollur 《Molecules (Basel, Switzerland)》2022,27(8)
Cancer is one of the leading causes of death worldwide, accountable for a total of 10 million deaths in the year 2020, according to GLOBOCAN 2020. The advancements in the field of cancer research indicate the need for direction towards the development of new drug candidates that are instrumental in a tumour-specific action. The pool of natural compounds proves to be a promising avenue for the discovery of groundbreaking cancer therapeutics. Elaeocarpus ganitrus (Rudraksha) is known to possess antioxidant properties and after a thorough review of literature, it was speculated to possess significant biomedical potential. Green synthesis of nanoparticles is an environmentally friendly approach intended to eliminate toxic waste and reduce energy consumption. This approach was reported for the synthesis of silver nanoparticles from two different solvent extracts: aqueous and methanolic. These were characterized by biophysical and spectroscopic techniques, namely, UV-Visible Spectroscopy, FTIR, XRD, EDX, DLS, SEM, and GC-MS. The results showed that the nanoconjugates were spherical in geometry. Further, the assessment of antibacterial, antifungal, and antiproliferative activities was conducted which yielded results that were qualitatively positive at the nanoscale. The nanoconjugates were also evaluated for their anticancer properties using a standard MTT Assay. The interactions between the phytochemicals (ligands) and selected cancer receptors were also visualized in silico using the PyRx tool for molecular docking. 相似文献
509.
Om Prakash Rajesh Kumar Deepak Sharma Rajesh Naithani Ravi Kumar 《Heteroatom Chemistry》2006,17(7):653-655
Oxidation of bis‐2,4‐pyrimidinylhydrazones of various araldehydes with two equivalents of iodobenzene diacetate in dichloromethane provides an efficient and easy method for the synthesis of eight new 3,9‐diaryl‐bis‐1,2,4‐triazolo[4,3‐a][4,3‐c]pyrimidines. © 2006 Wiley Periodicals, Inc. Heteroatom Chem 17:653–655, 2006; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/hc.20250 相似文献
510.
Subhrajyoti Bhandary Gulshan Rani S. R. N. Kiran Mangalampalli G. B. Dharma Rao Upadrasta Ramamurty Deepak Chopra 《化学:亚洲杂志》2019,14(5):607-611
The nanomechanical responses of two crystalline phases of a dihydropyrimidine analogue ( 1 ) were similar irrespective of the presence (or absence) of the guest solvent. In contrast, the mechanical responses of two differently solvated forms of the second related ( 2 ) crystals were significantly different. These contrasting behaviors are rationalized in terms of intermolecular interactions and energy distributions. 相似文献