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141.
Praveen K. Bayannavar Saba Kauser J. Shaikh S. Madan Kumar Mahadev N. Kumbar Aravind R. Nesaragi 《合成通讯》2019,49(16):2005-2016
A simple and convenient approach for the synthesis of pyrazolyl-tetrahydroindazolones via L-proline catalyzed three component domino reaction of arylhydrazine, dimedone and pyrazole aldehyde in polyethyleneglycol-400 (PEG-400) under microwave irradiation is described. This novel and green protocol proceeds smoothly in good to excellent yields and provides several advantages such as shorter reaction time, metal-free reaction conditions, simple work-up procedures. Also, recycling of the catalyst and solvent was observed without the loss of activity for three (03) runs. 相似文献
142.
Muhammad Hanif Muhammad Rafiq Muhammad Saleem Muhammad Mustaqeem Saba Jamil Muhammad Ramzan Saeed Ashraf Janjua 《中国化学会会志》2019,66(5):500-505
The development of a fluorescent sensor for the trace detection of the metallic contamination in the ecosystem and biological media have been a demand to reduce the health risk and environmental protection. Herein, we report the synthesis of 2‐formyl‐5‐picolinyl‐substituted rhodamine B derivative through Schiff base formation for the trace detection of the copper ions in the aqueous organic media as well as inside the live cells via bioimaging experiments. The ligand was successfully employed to detect the minute copper level ratiometrically through the chromogenic and fluorogenic response. The detection limit of the sensor was found to be 0.54 × 10?9 mol/L using 3 σ/slope relations. The reversible behavior of the ligand copper complex was determined using sulfide ions that regenerate the entire native properties of the ligands by snatching copper from the complex. The bioimaging experimental results represent the efficient membrane permeability of ligands with the minimum level of toxicity in the measured range found by the MTT assay. The appearance of bright red fluorescence from the BHK‐21 (hamster kidney fibroblast) cells upon treatment of the ligand incubated cells with the copper ions represents the utility of the proposed sensor for the copper detection probe in the intracellular media. 相似文献
143.
You-Rim Cha Saba Sajjad Kyung Ho Han Tae-Sung Yoon Heung-Seon Shin Sunghyun Kang 《Electrophoresis》2021,42(14-15):1516-1520
Efficient antibody incubation is a vital step for successful western blot. During the incubation, a thin antibody-depleted layer is created around the blotting membrane, which limits antibody binding. Although the conventional batch shaking method is ineffective against it, this layer can be easily disrupted by cyclic draining and replenishing (CDR) of the antibody solution during membrane incubation. Previously, we introduced a closed and rotating cylindrical chamber as a tool to implement CDR for western blots (rCDR). A new open bucket-style chamber was devised for easier operation and the possibility of process automation. Instead of rotation as in rCDR, rocking it back and forth achieved the CDR antibody incubation (R-CDR). The chamber was then equipped with a spreader-rod to facilitate the uniform movement of the antibody solution across the membrane surface. Hence, it was named spreader CDR (S-CDR). Compared to the batch incubation method, both the S-CDR and R-CDR devices produced significantly enhanced signals and developed faster results. There were several additional benefits of using the spreader-rod, which included uniform antibody binding across the membrane, reduced usage of antibodies, and the ability to recover results even from mishandled, creased membranes. The S-CDR device ensures better blots and can be easily implemented in existing western blot protocols. 相似文献
144.
Aziz Taha Javaid Saba Aziz Asim Sadiq M. A. 《Journal of Thermal Analysis and Calorimetry》2021,143(2):985-1002
Journal of Thermal Analysis and Calorimetry - The fully developed boundary layer flow and heat transfer model of an unsteady, incompressible, electrically conducting, optically thick and... 相似文献
145.
Muhammad Danish Rabia Ayub Butt Saba Akbar Muhammad Ashfaq Graham Smith 《Journal of chemical crystallography》2016,46(10-12):421-428
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148.
Polycaprolactone (PCL) is a bioresorbable and biocompatible polymer that has been widely used in long-term implants and controlled drug release applications. However, when it comes to tissue engineering, PCL suffers from some shortcomings such as slow degradation rate, poor mechanical properties, and low cell adhesion. The incorporation of calcium phosphate-based ceramics and bioactive glasses into PCL has yielded a class of hybrid biomaterials with remarkably improved mechanical properties, controllable degradation rates, and enhanced bioactivity that are suitable for bone tissue engineering. This review presents a comprehensive study on recent advances in the fabrication and properties of PCL-based composite scaffolds containing calcium phosphate-based ceramics and bioglasses in terms of porosity, degradation rate, mechanical properties, in vitro and in vivo biocompatibility and bioactivity for bone regeneration applications. The fabrication routes range from traditional methods such as solvent casting and particulate leaching to novel approaches including solid free-form techniques. 相似文献
149.
Selective electroless metal deposition using microcontact printing of phosphine-phosphonic acid inks
Carmichael TB Vella SJ Afzali A 《Langmuir : the ACS journal of surfaces and colloids》2004,20(13):5593-5598
We report a low-cost approach to selectively deposit films of nickel and copper on glass substrates. Our approach uses microcontact printing of organic inks containing phosphonic acid groups to bind the ink to a glass substrate and phosphine groups to bind a colloidal catalyst that initiates electroless metallization. We demonstrate this procedure by fabricating patterned nickel and copper films with areas as large as 15 cm2 and minimum feature sizes of approximately 2 microm. We present studies on the use of two ink types, an oligomer and a bifunctional molecule, and demonstrate that pattern quality and adhesion of the metallized films depends on the molecular weight of the ink and the ratio of phosphine and phosphonic acid groups. 相似文献
150.
Antonio Selva Francesco Ferrario Antonio Saba 《Journal of mass spectrometry : JMS》1987,22(4):189-196
The gaseous ionic products of 1-diazo-3-phenoxypropan-2-one upon electron impact show that cyclization reactions, which have counterparts in condensed-phase chemistry, occur in competition with a mass spectral Wolff type rearrangement. 相似文献