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91.
92.
K. Kasi Amarnath Reddy Smriti Moi Ashwini Dolle Basavaprabhu Hosamani Kiran Krishnamurthy Sunita Prakash Srinivasarao Raghothama Konkallu Hanumae Gowd 《Helvetica chimica acta》2020,103(7):e2000062
Dimedone is the most widely used chemical probe for detection of cysteine sulfenic acid in peptides and proteins. The reaction of dimedone with cysteine sulfenic acid results in the formation of unique cysteine dimedone motif containing thioether bridge. Based on the structure of cysteine dimedone residue in polypeptide, a new building block of Fmoc-Cys(Dmd)-OH was developed for solid phase synthesis of peptide cysteine dimedone. Mass spectrometric sequencing of synthetic peptides have confirmed successful incorporation of cysteine dimedone in peptide chain using HBTU/HOBt as a coupling agent. The new method permits synthesis of peptides containing both cysteine thiol and cysteine dimedone in the same sequence which was difficult to achieve by conventional methods. The synthetic peptide of glutathione cysteine dimedone was used as a standard in probing the air-mediated oxidation of thiol to disulfide form of glutathione. The co-elution of standard peptide and reaction mixture of oxidation of glutathione in presence of dimedone using RP-HPLC have confirmed the formation of glutathione cysteine sulfenic as an intermediate in the air-mediated oxidation of glutathione. The synthetic peptides of cysteine dimedone may find application in the field of redox proteomics and generation of antibodies against modified cysteine residue. 相似文献
93.
Ram Singh Prakash Biswas Prateek K. Jha 《International journal of quantum chemistry》2020,120(14):e26239
Extensive density functional theory calculations are performed to analyze the structure and activity of Cu and Cu Zn/Cu ZnO clusters containing up to 10 Cu/Zn atoms. The minimum-energy structures of Cu Zn and Cu ZnO clusters are found by doping minimum-energy pure Cu clusters with Zn atom(s) and ZnO molecule(s), respectively, followed by energy minimization of the resultant clusters. Odd-even alteration in properties that determine cluster stability/activity is observed with cluster size, which may be attributed to the presence/absence of unpaired electrons. The difference in behavior between Zn/ZnO doping can be interpreted in terms of charge transfer between atoms. Charge transfers from Zn to Cu in the Cu Zn clusters and from Cu and Zn atoms to O atom in Cu-ZnO clusters, which implies that the Cu atom acts as an electron acceptor in the Cu Zn clusters but not in the Cu ZnO clusters. Finally, the adsorption energies of glycerol and hydrogen on Cu Zn/Cu ZnO clusters are computed in the context of the use of Cu Zn/Cu ZnO catalysts in glycerol hydrogenolysis. Glycerol adsorption is generally found to be more energetically favorable than hydrogen adsorption. Dual-site glycerol adsorption is also observed in some of the planar clusters. Fundamental insights obtained in this study can be useful in the design of Cu Zn/Cu ZnO catalysts. 相似文献
94.
Hideyuki Tatsuno Kasper S. Kjr Kristjan Kunnus Tobias C. B. Harlang Cornelia Timm Meiyuan Guo Pavel Chbera Lisa A. Fredin Robert W. Hartsock Marco E. Reinhard Sergey Koroidov Lin Li Amy A. Cordones Olga Gordivska Om Prakash Yizhu Liu Mads G. Laursen Elisa Biasin Frederik B. Hansen Peter Vester Morten Christensen Kristoffer Haldrup Zoltn Nmeth Dorottya Srosin Szemes va Bajnczi Gyrgy Vank Tim B. Van Driel Roberto Alonso‐Mori James M. Glownia Silke Nelson Marcin Sikorski Henrik T. Lemke Dimosthenis Sokaras Sophie E. Canton Asmus O. Dohn Klaus B. Mller Martin M. Nielsen Kelly J. Gaffney Kenneth Wrnmark Villy Sundstrm Petter Persson Jens Uhlig 《Angewandte Chemie (International ed. in English)》2020,59(1):364-372
Iron N‐heterocyclic carbene (NHC) complexes have received a great deal of attention recently because of their growing potential as light sensitizers or photocatalysts. We present a sub‐ps X‐ray spectroscopy study of an FeIINHC complex that identifies and quantifies the states involved in the deactivation cascade after light absorption. Excited molecules relax back to the ground state along two pathways: After population of a hot 3MLCT state, from the initially excited 1MLCT state, 30 % of the molecules undergo ultrafast (150 fs) relaxation to the 3MC state, in competition with vibrational relaxation and cooling to the relaxed 3MLCT state. The relaxed 3MLCT state then decays much more slowly (7.6 ps) to the 3MC state. The 3MC state is rapidly (2.2 ps) deactivated to the ground state. The 5MC state is not involved in the deactivation pathway. The ultrafast partial deactivation of the 3MLCT state constitutes a loss channel from the point of view of photochemical efficiency and highlights the necessity to screen transition‐metal complexes for similar ultrafast decays to optimize photochemical performance. 相似文献
95.
Gopal Lamichhane Prakash Raj Pandeya Ramakanta Lamichhane Su-jin Rhee Hari Prasad Devkota Hyun-Ju Jung 《Molecules (Basel, Switzerland)》2022,27(3)
Background: Ponciri Fructus, a crude drug consisting of the dried immature fruits of Poncirus trifoliata (L.) Raf., is a popular folk medicine used for the treatment of allergy and gastrointestinal disorders in Korea and China. In this study, the anti-adipogenic activity of extracts and isolated compounds were evaluated using 3T3-L1 preadipocytes. Methods: Dried immature fruits were extracted and fractionated into n-hexane, ethyl acetate (EtOAc), n-butanol and water-soluble fractions. The ethanol extract and fractions were tested for anti-adipogenic activity in the 3T3-L1 cell line. The active fractions (n-hexane and EtOAc fractions) were further subjected to chromatographic techniques to isolate and identify active compounds. Furthermore, the isolated compounds were evaluated for their anti-adipogenic activity. Results: Altogether, seven compounds, including two flavonoids, one phytosteroid and four coumarin derivatives, were isolated. Ethanol extract, n-hexane fraction, EtOAc fraction and three isolated compounds (phellopterin, oxypeucedanin and poncirin) showed significant anti-adipogenic activity as observed by reduced lipid deposition in differentiated 3T3-L1 cells. Further, oxypeucedanin downregulated the key adipogenic markers, such as peroxisome proliferator-activated receptors proteins γ (PPAR-γ), sterol response element binding proteins-1 (SREBP-1), CCAAT/enhancer binding proteins-α (C/EBP-α), adipocyte-specific lipid binding proteins (FABP-4), adipocyte fatty acid binding proteins (aP2), lipoprotein lipase (LPL) and leptin. Conclusion: This study indicated that the ethanol extract, hexane fraction and ethyl acetate fraction of P. trifoliata fruits possess strong anti-adipogenic activity, containing the active compounds such as phellopterin, oxypeucedanin and poncirin. Further research is recommended to explore their efficacy and safety in animal and clinical models. 相似文献
96.
Tripathi Jai Prakash Jana Debaldev Vyshnavi Devi N. S. N. V. K. Tiwari Vandana Abbas Syed 《Nonlinear dynamics》2020,102(1):511-535
Nonlinear Dynamics - In this present study, we systematically explore the periodicity (almost periodic nature) of a dynamical system in time-varying environment, which portrays a special case of... 相似文献
97.
We investigate a double cavity optomechanical system generating single and double Fano resonance (multi-Fano). By altering a single parameter, the tunnelling rate g of the middle mirror, we are able to switch between single and double Fano line shapes. The first spectral line shape is stronger in the case of multi-Fano than in the case of single Fano. Also the behaviour of the steady state value of the displacement of the middle mirror, with respect to g, heavily influences the behaviour of double Fano lines in our scheme. This tunability along with using a single pump and signal/probe laser has an added advantage in situations where only low power consumption is available. 相似文献
98.
99.
Daniel L. Obrzut Prakash M. Adekkanattu Jyothi Thundimadathil Jing Liu Delphine R. Dubois James A. Guin 《Reaction Kinetics and Catalysis Letters》2003,80(1):113-121
SAPO-34 silicoaluminophosphate molecular sieve produces large amounts of methane at elevated temperatures in the methanol
to olefins (MTO) process. This significantly reduces the lower olefins selectivity a key factor in determining the commercial
viability of this catalyst. Impregnation of the SAPO-34 molecular sieve with metal ions such as K, Cs, Pt, Ag and Ce was found
to reduce the amount of methane significantly at higher temperatures thereby increasing the lower olefins selectivity. This
observed effect is less apparent at lower temperatures where the amount of methane formed is generally low.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
100.
S. Ramasamy D. J. Smith P. Thangadurai K. Ravichandran T. Prakash K. PAdmaprasad V. Sabarinathan 《Pramana》2005,65(5):881-891
The ultra high vacuum chamber was developed in the Department of Nuclear Physics, University of Madras with the funding from
DST, India. This UHV chamber is used to prepare nanocrystalline materials by inert gas condensation technique (IGCT). Nanocrystalline
materials such as PbF2, Mn2+-doped PbF2, Sn-doped In2O3 (ITO), ZnO, Al2O3, Ag2O, CdO, CuO, ZnSe:ZnO etc., were prepared by this technique and characterized. Results of some of these materials will be
presented in this paper. In solid-state207Pb NMR on PbF2 a separate signal due to the presence of grain boundary has been observed. The structural phase transition pressure during
the phase transformation from the cubic phase to orthorhombic phase under high pressure shows an increase with the decrease
in grain size. Presence of electronic centres in nanocrystalline PbF2 is observed from Raman studies and the same has been confirmed by photoluminescence studies. Al2O3 was prepared and56Fe ions were implanted. After implantation segregation of56Fe ions was examined by SEM. The oxidation properties of ITO were studied by HRTEM. As against the expectation of oxide coating
on individual nanograins of In-Sn alloy, ITO nanograins grew into faceted nanograins on heat treatment in air and O2 atmosphere. The growth of ITO under O2 atmosphere showed pentagon symmetry. The PMN was initially prepared by solid-state reaction. Further, this PMN relaxor material
will be used to convert into nanocrystalline PMN by IGCT with sputtering and will be studied 相似文献