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541.
In this report, the thickness‐dependent carbon monooxide (CO)‐sensing characteristics of sputtered zinc oxide (ZnO) films are investigated, followed by their morphological and electrical characterizations. ZnO films, ≈21 nm, show repeatable and high change in their resistances on exposure to CO and the observed maximum response is ≈52.2%, whereas ≈219 nm films fail to show reproducibility in sensing performance. Response and recovery time of ≈21 nm films are ≈28 and 250 s, which are faster than the time observed in case of ≈219 nm films. An ≈21 nm film is able to resolve 100 parts‐per‐billions (ppb) CO concentration in air. Later, on‐chip integration of ≈21 nm film is successfully implemented on specifically designed Micro‐Electro‐Mechanical‐System (MEMS) platform, inbuilt with microheater and utilizes power of ≈23.7 Milliwatts (mW) (375 °C). The packaged sensor chip is further tested and qualified for indoor and outdoor detection of CO gas in the atmosphere. 相似文献
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543.
Tian‐Jun Yue Gulzar A. Bhat Wen‐Jian Zhang Wei‐Min Ren Xiao‐Bing Lu Donald J. Darensbourg 《Angewandte Chemie (International ed. in English)》2020,59(32):13633-13637
Topological polymers possess many advantages over linear polymers. However, when it comes to the poly(monothiocarbonate)s, no topological polymers have been reported. Described herein is a facile and efficient approach for synthesizing well‐defined branched poly(monothiocarbonate)s in a “grafting through” manner by copolymerizing carbonyl sulfide (COS) with epichlorohydrin (ECH), where the side‐chain forms in situ. The lengths of the side‐chains are tunable based on reaction temperatures. More importantly, enhancement in thermal properties of the branched copolymer was observed, as the Tg value increased by 22 °C, compared to the linear analogues. When chiral ECH was utilized, semicrystalline branched poly(monothiocarbonate)s were accessible with a Tm value of 112 °C, which is 40 °C higher than that of the corresponding linear poly(monothiocarbonate)s. The strategy presented herein for synthesizing branched polymers provides efficient and concise access to topological polymers. 相似文献
544.
Zahid Rafiq Bhat Manvendra Kumar Nisha Sharma Umesh Prasad Yadav Tashvinder Singh Gaurav Joshi Brahmam Pujala Mohd Raja Joydeep Chatterjee Kulbhushan Tikoo Sandeep Singh Raj Kumar 《Molecules (Basel, Switzerland)》2022,27(17)
Tyrosine kinase inhibitors are validated therapeutic agents against EGFR-mutated non-small cell lung cancer (NSCLC). However, the associated critical side effects of these agents are inevitable, demanding more specific and efficient targeting agents. Recently, we have developed and reported a non-covalent imidazo[1,2-a]quinoxaline-based EGFR inhibitor (6b), which showed promising inhibitory activity against the gefitinib-resistant H1975(L858R/T790M) lung cancer cell line. In the present study, we further explored the 6b compound in vivo by employing the A549-induced xenograft model in nude mice. The results indicate that the administration of the 6b compound significantly abolished the growth of the tumor in the A549 xenograft nude mice. Whereas the control mice bearing tumors displayed a declining trend in the survival curve, treatment with the 6b compound improved the survival profile of mice. Moreover, the histological examination showed the cancer cell cytotoxicity of the 6b compound was characterized by cytoplasmic destruction observed in the stained section of the tumor tissues of treated mice. The immunoblotting and qPCR results further signified that 6b inhibited EGFR in tissue samples and consequently altered the downstream pathways mediated by EGFR, leading to a reduction in cancer growth. Therefore, the in vivo findings were in corroboration with the in vitro results, suggesting that 6b possessed potential anticancer activity against EGFR-dependent lung cancer. 6b also exhibited good stability in human and mouse liver microsomes. 相似文献
545.
Vineetha K K;Archana P R;Bhamini Krishna Rao;Mamatha Ballal;Babi Dutta;Vani Lakshmi R;Rajeshwari G. Bhat; 《Rapid communications in mass spectrometry : RCM》2024,38(24):e9923
The exploration of the gut microbiome and related metabolites holds an exciting future in health science. The challenges associated with fecal sample testing are proper sample collection, sterile transportation, optimal transport conditions, and processing as all these factors could potentially change the microbiome composition, further exacerbated by the patient's customary discomfort regarding feces samples. The study aimed to compare the usage of rectal swabs and stool samples for short-chain fatty acid estimation using gas chromatography–mass spectrometry (GC–MS) and indole estimation using spectrophotometry. 相似文献
546.
Lakshmi V.R. Babu Syamala Trimbak B. Mete Ramakrishna G. Bhat 《Tetrahedron letters》2018,59(34):3288-3291
FeCl3·6H2O/triethylsilane composite catalyst system is successfully developed for the selective conjugate reduction of carbon-carbon double bond of Michael acceptor-alkylidene-β-keto esters and alkylidene-1,3-diketones under mild reaction conditions to afford the corresponding saturated β-keto esters and 1,3-diketones. The process involves the iron-catalyzed hydrosilylation, followed by in situ hydrolysis of silyl enol ether. The optimal reaction conditions include 20?mol% of FeCl3·6H2O and triethylsilane in dichloromethane at room temperature. A broad range of substrates undergoes the reduction in 1, 4-selective manner to afford the corresponding saturated compounds in excellent yields. 相似文献
547.
Acetonitrile and acrylonitrile were plasma polymerized on Polypropylene (PP) surface. Surface modifications were characterized by surface energy measurements and ATR-FTIR spectroscopy. Surface energy measurement showed incorporation of hydrophilic groups along with deposition of cross-linked network of plasma-polymerized product. ATR-FTIR analysis of modified films showed incorporation of conjugated imine and amine groups. Using change in the relative intensities of C—H stretch bands of polypropylene surface, site of attachment of hydrophilic group and most predominant surface chemical reaction could be inferred. Chemical nature of plasma polymerized product was studied using FTIR by KBr disc method. Adhesion test was performed on modified surface by peel test method. Surface energy and peel strength measurements were performed for the samples aged for 2 months in order to check the durability of surface modification. 相似文献
548.
Puri SC Handa G Bhat BA Gupta VK Amna T Verma N Anand R Dhar KL Qazi GN 《Journal of chromatographic science》2005,43(7):348-350
The present work describes the isolation of camptothecin and 9-methoxycamptothecin from the aerial parts of Nothapodytes foetida by semipreparative high-performance liquid chromatography because the separation of compounds by conventional procedures is tedious and cumbersome. The purity of the isolates is determined by physicochemical data and liquid chromatography-mass spectrometry. 相似文献
549.
550.
Abachi S Abbott B Abolins M Acharya BS Adam I Adams DL Adams M Ahn S Aihara H Alitti J Álvarez G Alves GA Amidi E Amos N Anderson EW Aronson SH Astur R Avery RE Baden A Balamurali V Balderston J Baldin B Bantly J Bartlett JF Bazizi K Bendich J Beri SB Bertram I Bezzubov VA Bhat PC Bhatnagar V Bhattacharjee M Bischoff A Biswas N Blazey G Blessing S Bloom P Boehnlein A Bojko NI Borcherding F Borders J Boswell C Brandt A Brock R Bross A Buchholz D Burtovoi VS Butler JM Casey D Castilla-Valdez H 《Physical review letters》1995,75(20):3618-3623