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Efficient Total Chemical Synthesis of 13C=18O Isotopomers of Human Insulin for Isotope‐Edited FTIR 下载免费PDF全文
Dr. Balamurugan Dhayalan Dr. Ann Fitzpatrick Dr. Kalyaneswar Mandal Dr. Jonathan Whittaker Prof. Dr. Michael A. Weiss Prof. Dr. Andrei Tokmakoff Prof. Dr. Stephen B. H. Kent 《Chembiochem : a European journal of chemical biology》2016,17(5):415-420
Isotope‐edited two‐dimensional Fourier transform infrared spectroscopy (2 D FTIR) can potentially provide a unique probe of protein structure and dynamics. However, general methods for the site‐specific incorporation of stable 13C=18O labels into the polypeptide backbone of the protein molecule have not yet been established. Here we describe, as a prototype for the incorporation of specific arrays of isotope labels, the total chemical synthesis—via a key ester insulin intermediate—of 97 % enriched [(1‐13C=18O)PheB24] human insulin: stable‐isotope labeled at a single backbone amide carbonyl. The amino acid sequence as well as the positions of the disulfide bonds and the correctly folded structure were unambiguously confirmed by the X‐ray crystal structure of the synthetic protein molecule. In vitro assays of the isotope labeled [(1‐13C=18O)PheB24] human insulin showed that it had full insulin receptor binding activity. Linear and 2 D IR spectra revealed a distinct red‐shifted amide I carbonyl band peak at 1595 cm?1 resulting from the (1‐13C=18O)PheB24 backbone label. This work illustrates the utility of chemical synthesis to enable the application of advanced physical methods for the elucidation of the molecular basis of protein function. 相似文献
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S. Swathi R. Yuvakkumar G. Ravi E. Sunil Babu Dhayalan Velauthapillai Sulaiman Ali Alharbi 《Ceramics International》2021,47(5):6521-6527
Photoelectrochemical (PEC) water splitting is beneficial and has received attractive attention due to a greater potential to generate hydrogen and oxygen from water by using plentiful solar light to solve the problem of energy crisis. Various active semiconductor materials are used in PEC water splitting applications. Nevertheless, in past decades, most of the researchers suggested that titanium oxide (TiO2) is the best photoanode for this type of applications. Now, Zinc oxide (ZnO) is considered a perfect substitution to TiO2 due to its comparable energy band structure and superior photogenerated electron transfer rate. In this study, bare and phosphorous-doped ZnO nanorods were successfully developed on fluorine-doped tin oxide-coated glass (FTO) substrate by chemical vapor deposition. X-ray diffraction (XRD) pattern authenticated hexagonal structure formation with strong diffraction peak of (101), which showed that ZnO nanorods were perfectly developed along c axis. The optical and morphological properties were analyzed by UV–Vis and scanning electron microscopy images. The energy-dispersive X-ray spectra demonstrated that doping agent phosphorous was present in ZnO nanorods. The PEC properties of the developed ZnO nanorods were further investigated and obtained results suggested that a small amount of phosphorous-doped ZnO nanorods enhances their PEC performance. 相似文献
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This paper reports simulations of the generation of Lamb wave modes in thin plates using a meander coil (meander line) EMAT, which works under the principle of Lorentz force mechanism in non-magnetic materials. The numerical simulations have been compared with measurements. The numerical work presented in this paper is divided into two parts. First, a 2D electromagnetic model is developed for calculating the Lorentz force density, which is the driving force for elastic wave generation within the plate. Second, the calculated force at each point in the metal is used as the driving force for generating elastic wave modes in the plate. These calculated Lamb wave modes are compared with those generated experimentally in a thin plate. Additionally, the measured wave modes are analyzed with the help of dispersion curves and a time–frequency analysis. Our numerical work is also extended to analyze the interaction of Lamb wave modes with defects. The simulations compare favorably with the measurements presented here. 相似文献
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M. Raja N. Muthukumarasamy Dhayalan Velauthapillai R. Balasundraprabhu S. Agilan T. S. Senthil 《Journal of Materials Science: Materials in Electronics》2014,25(11):5035-5040
Aluminium doped and copper doped ZnO nanostructured thin films have been prepared using simple solgel dip coating method. The X-ray diffraction pattern results revealed that the prepared Al and Cu doped ZnO sample exhibits hexagonal structure. The average crystallite size of pure ZnO, Al doped ZnO and Cu doped ZnO samples were found to be 29, 26 and 15 nm, respectively. The optical band gap of ZnO, Al doped ZnO and Cu doped ZnO thin films was found to be 3.27, 3.29, and 3.20 eV respectively. Solar cells have been fabricated using CdS quantum dots sensitized ZnO nanostructured thin films and the efficiency of the fabricated Al doped and Cu doped ZnO solar cells were 1.37 and 1.29 % respectively. 相似文献
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B. Jansi Rani R. Yuvakkumar G. Ravi Mehboobali Pannipara Abdullah G. Al-Sehemi Dhayalan Velauthapillai 《International Journal of Hydrogen Energy》2021,46(36):18719-18728
Solvothermal Bi2MoO6 hierarchical microflowers synthesis has been successfully attempted. Methanol, ethanol and isopropanol have been mediated to synthesize three kinds of Bi2MoO6 hierarchical microflowers. Highly oriented (311) plane growth of orthorhombic Bi2MoO6 hierarchical microflowers have been confirmed. Interstitial vacancies and its role on electrochemical activity have been extensively discussed. Electrode fabrication was constructively done by using Ni foam substrate. Half cell arrangement of each electrode in alkaline medium has been designed to measure the electrochemical activity towards water oxidation. High current density of 356 mA/cm2 was afforded by Bi2MoO6 hierarchical microflowers mediated by ethanol solvent during synthesis. Low Tafel slope value of 43 mV/dec has been reported to obtain 10 mA/cm2 current density. Higher conductivity long with very good electron transportation has been achieved and is also adapted for 12 h long time stability test and achieved 86% of retention in its performance. Hence, optimally prepared Bi2MoO6 hierarchical microflowers could be an efficient electrode for clean energy fabrication. 相似文献
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M. Thambidurai N. Muthukumarasamy Dhayalan Velauthapillai S. Agilan R. Balasundaraprabhu 《Journal of Electronic Materials》2012,41(4):665-672
In the present work, a systematic study has been carried out to understand the influence of cobalt (Co) doping on various
properties of CdS nanoparticles. CdS and Co-doped CdS quantum dots have been prepared at room temperature using a chemical
precipitation method without using catalysts, capping agents, or surfactants. X-ray diffraction reveals that both undoped
and Co-doped CdS nanoparticles exhibit hexagonal structure without any impurity phase, and the lattice constants of CdS nanoparticles
are observed to decrease slightly with increasing cobalt concentration. High-resolution transmission electron microscopy (HRTEM)
shows that the particle size of CdS and 5.02% Co-doped CdS nanoparticles is in the range of 2 nm to 4 nm. The Raman spectra
of Co-doped CdS nanoparticles exhibit a red-shift compared with that of bulk CdS, which may be attributed to optical phonon
confinement. The optical absorption spectra of Co-doped CdS nanoparticles also exhibit a red-shift with respect to that of
CdS nanoparticles. The electrical conductivity of CdS and Co-doped CdS nanoparticles is found to increase with increasing
temperature and cobalt concentration. 相似文献
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N. Gokilamani N. Muthukumarasamy M. Thambidurai A. Ranjitha Dhayalan Velauthapillai T. S. Senthil R. Balasundaraprabhu 《Journal of Materials Science: Materials in Electronics》2013,24(9):3394-3402
Nanocrystalline TiO2 dye-sensitized solar cells have been fabricated using TiO2 photoelectrode sensitized using the extracts of red rose and table rose as natural sensitizers and their characteristics have been studied. The extracts having anthocyanin pigment (pelargonidin, peonidin and cyanidin), which have hydroxyl and carboxylic groups in the molecule can attach effectively to the surface of TiO2 film. The solar cell constructed using the red rose sensitized TiO2 photo-electrode exhibited a short-circuit photocurrent of 4.57 mA/cm2 and a power conversion efficiency of 0.81 % and that of table rose sensitized TiO2 photo-electrode exhibited a short-circuit photocurrent of 4.23 mA/cm2 and a power conversion efficiency of 0.67 %. Natural dye sensitized TiO2 photo electrodes present the prospect to be used as an environment-friendly, low-cost alternative system. 相似文献
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Subina Raveendran Mohd. Imran K. Khan Arunkumar Dhayalan S. Kannan 《Journal of the American Ceramic Society》2020,103(3):1549-1562
NiFe2O4/ZrO2 composite with varied compositional ratios was formed through solution-based sol-gel synthetic route. The ability to retain NiFe2O4/ZrO2 composite structures was dependent on the concomitant effect of temperature gradient and precursor concentration. The crystallization of t-ZrO2 alongside the incidence of NiFe2O4 and NiO was evident at 900°C. However, the gradual elimination of NiO and simultaneous enhancement in NiFe2O4 content is inevitable at 1300°C. Morphological analysis of the composite revealed discrete distribution of ZrO2 and NiFe2O4 grains and also portrays the dense and pore-free microstructures. Despite the presence of varied amount of NiFe2O4 in the composites, the resultant mechanical properties displayed relatively better values and exhibited good similarities with the hard tissue. As expected, a gradual increment in the ferrimagnetic properties as a function of enhanced NiFe2O4 content was induced. Further, in vitro analysis delivered good biocompatibility features of the investigated NiFe2O4/ZrO2 composite. 相似文献
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J J Stamnes V Dhayalan 《Journal of the Optical Society of America. A, Optics, image science, and vision》2001,18(7):1662-1669
We study the transmission of a two-dimensional (2-D) TM Gaussian beam through a plane interface between an isotropic medium (e.g., air) and a uniaxially anisotropic crystal. The optic axis of the crystal is taken to be in the plane of incidence but is arbitrarily oriented relative to the interface normal. We show that, in the paraxial approximation, a nontruncated transmitted 2-D TM Gaussian beam inside a uniaxial crystal can be expressed in a form similar to that of a scalar Gaussian beam that propagates in a homogeneous medium. We also show that the transmitted beam corresponding to an incident 2-D TM Gaussian beam with its main propagation direction along the interface normal is tilted inside the crystal by the same angle as is the transmitted axial ray that corresponds to a normally incident ray. 相似文献