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781.
Vivek Kumar P. Thakur A. K. Bhati R. P. Singh R. K. Bhowmik 《Hyperfine Interactions》2007,175(1-3):121-129
The spectroscopic quadrupole moments of the K π = 8? isomers in 170Hf and 172Hf, Q s ?=?4.91(17) b and 5.40(19) b, respectively and Q s ?=?4.92(17) b for K π ?=?23/2? in 171Hf have been measured using the time differential perturbed angular distribution technique. The nuclear reaction 160Gd(16O, xnγ) was used to excite the respective isomeric states and for the recoil implantation of Hf nuclei into the Hf foil. The quadrupole deformation for the 8? isomer and the ground state has the same value. The deformation corresponding to 23/2? isomeric state is observed to be reduced with respect to the ground state due to the i 13/2 neutron alignment. The results are in good agreement with the multi-quasiparticle calculations. 相似文献
782.
Redox enzymes catalyze major reactions in microorganisms to supply energy for life. Their use in electrochemical biodevices requires their integration on electrodes, while maintaining their activity and optimizing their stability. In return, such applicative development puts forward the knowledge on involved catalytic mechanisms, providing a direct electrode connection of the enzyme is fulfilled. Enzymes being large molecules with active site embedded in an insulating moiety, direct bioelectrocatalysis supposes strategies for specific orientation of the enzyme to be developed. In this review, we summarize recent advances during the past 3 years in the chemical modification of electrodes favoring direct electrocatalysis. We present the different methodologies used according to the electrode materials, including metals, carbon-based electrodes, or porous structures and discuss the gained insights into bioelectrocatalysis. We especially focus on enzyme engineering, which appears as an emerging strategy for enzyme anchoring. Remaining challenges will be discussed with regard to these later findings. 相似文献
783.
Balasubramanian Mariammal Adaikalam Shylaja Sundaravel Vivek Kumar Stephen Raja Rubina Raju Ranjith Kumar 《Journal of heterocyclic chemistry》2020,57(11):3882-3889
3-Amino-5-(thiazol-2-yl)-[1,1′-biaryl]-2,4-dicarbonitriles have been synthesized employing a facile one-pot pseudo four-component domino strategy. All these thiazole-tethered biaryls exhibited blue fluorescence under UV lamp. Based on the high relative quantum yield, three compounds namely, 4a , 4d , and 4i , were chosen to explore the metal interference studies. Against several metal ions, these three thiazole-tethered biphenyl probes were found to be effective fluorescent chemosensors for the selective and sensitive detection of Fe3+ ions with a lower detection limit of 0.18, 0.12, and 0.16 μM, respectively. 相似文献
784.
Manoj Gaur Mayurika Goel L. Sridhar Tara Devi S. Ashok S. Prabhakar P. Dureja P. Raghunathan S. V. Eswaran 《Monatshefte für Chemie / Chemical Monthly》2012,44(15):283-288
Abstract
Click chemistry was used to synthesize a series of biaryl-based bis(1,2,3-triazoles). Their antifungal activity was evaluated against three soil-borne plant pathogenic fungi, viz. Rhizoctonia bataticola, Sclerotium rolfsii, and Fusarium oxysporum, using the food poison technique at concentrations of 62.5–500 μg/cm3. 相似文献785.
We demonstrate the realization of fundamental logic operations, as well as a memory element, with engineered delayed synthetic gene networks. Further, we investigate the effect of time delay in different kinds of processes, on the operational range of this biological logic gate. We show that this delay can either enhance or diminish logic behavior, depending on its functional form. Lastly, we show that the desired response to inputs can be induced, even in the absence of noise, by time delay alone. 相似文献
786.
787.
Shweta Mehrotra Shailendra Goel Soom Nath Raina Vijay Rani Rajpal 《Applied biochemistry and biotechnology》2014,173(7):1790-1801
The analysis of plant genome structure and evolution requires comprehensive characterization of repetitive sequences that make up the majority of plant nuclear DNA. In the present study, we analyzed the nature of pCtKpnI-I and pCtKpnI-II tandem repeated sequences, reported earlier in Carthamus tinctorius. Interestingly, homolog of pCtKpnI-I repeat sequence was also found to be present in widely divergent families of angiosperms. pCtKpnI-I showed high sequence similarity but low copy number among various taxa of different families of angiosperms analyzed. In comparison, pCtKpnI-II was specific to the genus Carthamus and was not present in any other taxa analyzed. The molecular structure of pCtKpnI-I was analyzed in various unrelated taxa of angiosperms to decipher the evolutionary conserved nature of the sequence and its possible functional role. 相似文献
788.
Grafting of nylon 6 fiber was carried out using ethyl methacrylate (EMA) as the monomer in various water-alcohol systems (i.e., water-methanol, water-ethanol and water-n-propanol; water-alcohol ratio 1:1) at 70°C using a carbon arc lamp as the source of photochemical initiation. Percent graft add-on (% GAO) increases continuously and linearly with an increase in monomer concentration irrespective of the media used. The % GAO, however, decreases with an increase in the alkyl chain length of the alcohol used in the following order: water-methanol > water-ethanol > water-n-propanol. With an increase in the time period of grafting, % GAO and total polymer yield (% TPY) increase continuously in all three media whereas the grafting efficiency (GE) first increases and then falls after reaching a maximum level. Although a similar trend is maintained in the three systems, there is a decrease in overall % TPY and % GAO from the water-methanol system to the water-n-propanol system through the water-ethanol system. 相似文献
789.
790.
Twelve lichen species growing on different ecological habitats in East Antarctica were analyzed for Cr, Cu, Fe, Pb and Zn. All the species had consistently higher amounts of Fe and Cu, as their substrata were iron and copper mineralized rocks. the foliose and fruticose lichens had a greater concentration of heavy metals than the crustose ones. Significantly, lead was not detected in any sample indicating that the area is still free from pollution. 相似文献