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971.
972.
973.
Vinay S. Sharma B. B. Jain H. N. Chauhan R. B. Patel 《Molecular Crystals and Liquid Crystals》2016,630(1):79-86
Two ester homologous series of carboxy (-COO-) and ethylene-carboxy (-CH=CH-COO-) mesogens, viz. α-4-[4’-n-alkoxybenzoyloxy] phenyl β-4’’-methoxy benzoyl ethylenes (1) and α-4-[4’-n-alkoxy cinnamoyloxy phenyl β-4’’-methoxy benzoyl ethylenes (2)] are discussed. Series (1) and (2) differ at their central linking group. Mesophase are observed at four and five number members in both homologue series. Enantiotropic nematogenic property is observed in both series (1) and (2), while some smectic property is exhibited in series (2). Thermal stability of nematic-isotropic in series (1) is relatively low as compared to (2), smectogenic property is totally absent in series (2). In phase diagram, solid-nematic, solid-isotropic, and nematic-isotropic curve follow zigzag path rising and falling. Transition temperatures are observed through hot stage polarizing microscope. Analytical data supports the structure of molecules. Threaded, Schlieren-type textures of homologues are observed through microscope. 相似文献
974.
Dr. Piyush K. Jain Vyas Ramanan Dr. Arnout G. Schepers Nisha S. Dalvie Apekshya Panda Dr. Heather E. Fleming Prof. Sangeeta N. Bhatia 《Angewandte Chemie (International ed. in English)》2016,55(40):12440-12444
The ability to remotely trigger CRISPR/Cas9 activity would enable new strategies to study cellular events with greater precision and complexity. In this work, we have developed a method to photocage the activity of the guide RNA called “CRISPR‐plus” (CRISPR‐precise light‐mediated unveiling of sgRNAs). The photoactivation capability of our CRISPR‐plus method is compatible with the simultaneous targeting of multiple DNA sequences and supports numerous modifications that can enable guide RNA labeling for use in imaging and mechanistic investigations. 相似文献
975.
A novel sensitive electrochemical sensor has been developed by modification of glassy carbon electrode (GCE) with graphene (GRP), chitosan (CHIT), and bismuth oxide (Bi2O3) nanoparticles. The morphological characteristics of nanocomposite (GRP-CHIT-Bi2O3 or GCB) were studied by scanning electron microscope and atomic force microscopy. The electrochemical behavior of epinephrine at nanocomposite modified GCE (GCB/GCE) was investigated in pH 7.4 phosphate buffer solution using cyclic voltammetry and square wave voltammetry. GCB/GCE showed an enhancement in the current response as compared to bare GCE. Electrochemical impedance spectra showed a reduction of charge transfer resistance and higher electrocatalytic behavior of the sensor. The electrooxidation process of epinephrine at the modified sensor was found to be diffusion controlled. GCB/GCE showed a linear response to epinephrine in the range 100 to 500 nM. The limit of detection and limit of quantification were found to be 3.56 and 11.85 nM, respectively, which is lower than many other sensors reported for epinephrine in literature. The modified sensor showed high sensitivity (1.3 nA/nM) and selectivity for epinephrine. The method was employed for quantification of epinephrine in pharmaceutical formulation and human blood serum samples. 相似文献
976.
Dr. Younghoon Kim Dr. Zhenyu Yang Dr. Ankit Jain Dr. Oleksandr Voznyy Dr. Gi‐Hwan Kim Dr. Min Liu Li Na Quan Dr. F. Pelayo García de Arquer Dr. Riccardo Comin James Z. Fan Prof. Dr. Edward H. Sargent 《Angewandte Chemie (International ed. in English)》2016,55(33):9586-9590
Bismuth‐based hybrid perovskites are candidates for lead‐free and air‐stable photovoltaics, but poor surface morphologies and a high band‐gap energy have previously limited these hybrid perovskites. A new materials processing strategy to produce enhanced bismuth‐based thin‐film photovoltaic absorbers by incorporation of monovalent silver cations into iodobismuthates is presented. Solution‐processed AgBi2I7 thin films are prepared by spin‐coating silver and bismuth precursors dissolved in n‐butylamine and annealing under an N2 atmosphere. X‐ray diffraction analysis reveals the pure cubic structure (Fd3m) with lattice parameters of a=b=c=12.223 Å. The resultant AgBi2I7 thin films exhibit dense and pinhole‐free surface morphologies with grains ranging in size from 200–800 nm and a low band gap of 1.87 eV suitable for photovoltaic applications. Initial studies produce solar power conversion efficiencies of 1.22 % and excellent stability over at least 10 days under ambient conditions. 相似文献
977.
Nikhil Bajpayee Thangavel Vijayakanth Sigal Rencus-Lazar Sneha Dasgupta Aamod V. Desai Rahul Jain Ehud Gazit Rajkumar Misra 《Angewandte Chemie (International ed. in English)》2023,62(6):e202214583
Flexible and biocompatible metal peptide frameworks ( MPFs) derived from short and ultra-short peptides have been explored for the storage of greenhouse gases, molecular recognition, and chiral transformations. In addition to short flexible peptides, peptides with specifically folded conformations have recently been utilized to fabricate a variety of metal helix frameworks ( MHFs ). The secondary structures of the peptides govern the structure-assembly relationship and thereby control the formation of three-dimensional (3D)- MHFs . Particularly, the hierarchical structural organization of peptide-based MHFs has not yet been discussed in detail. Here, we describe the recent progress of metal-driven folded peptide assembly to construct 3D porous structures for use in future energy storage, chiral recognition, and biomedical applications, which could be envisioned as an alternative to the conventional metal-organic frameworks (MOFs). 相似文献
978.
Rajrani Narvariya Dr. Suman Das Susmita Mandal Dr. Archana Jain Prof. Tarun K. Panda 《欧洲无机化学杂志》2023,26(25):e202300247
We report catalytic hydroboration of esters as well as nitriles under solvent-free and mild conditions using single titanium(IV) metal complex, [{κ2-C6H4C(O)N(iPr)C(N-iPr)=N}{κ3-(iPr)N=C(O)−C6H4−NC(NMe2)N(iPr)}TiNMe2] 1 as a sustainable, economical, and efficient pre-catalyst. The molecular structure of the TiIV complex in the solid state reveals the unique coordination of TiIV metal with N, N, and O atoms of one quinazolinone unit via in-situ rearrangement, while another quinazolinone moiety coordinates in bidentate fashion via both N atoms only. The TiIV complex demonstrates excellent activity as a pre-catalyst towards the hydroboration of a wide array of esters and nitriles with pinacolborane (HBpin) to afford alkoxyboranes and diboryl amines in high yield (up to 99 %) with greater tolerance to a variety of electron-withdrawing and electron-donating functional groups. A most plausible mechanism of hydroboration of esters is also proposed based on kinetics and NMR studies, which suggests the formation of titanium-hydride species as an active catalyst. 相似文献
979.
Amita Puranik Rupanjan Goswami Purushottam Sutar Devika Tupe Pratap Rasam Prajakta Dandekar Ratnesh Jain 《Journal of separation science》2023,46(3):2200521
The therapeutic and immunological properties of biopharmaceuticals are governed by the glycoforms contained in them. Thus, bioinformatics tools capable of performing comprehensive characterization of glycans are significantly important to the biopharma industry. The primary structural elucidation of glycans using mass spectrometry is tricky and tedious in terms of spectral interpretation. In this study, the biosimilars of a therapeutic monoclonal antibody and an Fc-fusion protein with moderate and heavy glycosylation, respectively, were employed as representative biopharmaceuticals for released glycan analysis using liquid chromatography–tandem mass spectrometry instead of conventional mass spectrometry-based analysis. SimGlycan® is a software with proven ability to process tandem MS data for released glycans could identify eight additional glycoforms in Fc-fusion protein biosimilar, which were not detected during mass spectrometry analysis of released glycans or glyco-peptide mapping of the same molecule. Thus, liquid chromatography–tandem mass spectrometry analysis of released glycans not only complements conventional liquid chromatography–mass spectrometry-based glycan profiling but can also identify additional glycan structures that may otherwise be omitted during conventional liquid chromatography–tandem mass spectrometry based analysis of mAbs. The mass spectrometry data processing tools, such as PMI Byos™, SimGlycan®, etc., can display pivotal analytical capabilities in automated liquid chromatography–mass spectrometry and liquid chromatography–tandem mass spectrometry-based glycan analysis workflows, especially for high-throughput structural characterization of glycoforms in biopharmaceuticals. 相似文献
980.
Jain A Mohapatra M Godbole SV Tomar BS 《Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy》2008,71(3):1007-1010
Complexation of Eu(III) with alpha-hydroxy isobutyric acid (HIBA), a model compound of humic acid, has been studied by time resolved fluorescence spectroscopy. The ratio of fluorescence intensity of the two peaks at 616 and 592 nm (I(616/592)) was found to increase with increasing ligand to metal ratio. The I(616/592) data was used to deduce the stability constant of Eu-HIBA complexes of the type ML(i) (i=1-3). The formation of multiple ligand complexes was also corroborated by lifetime data which was found to increase with increasing [HIBA]/[Eu] ratio thus indicating replacement of coordinated water molecules by HIBA. 相似文献