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91.
The hydrogen bonding of 1:1 complexes formed between formamide and water molecule have been investigated systematically using Hartree–Fock (HF), hybrid density functional theory (B3LYP), and post‐Hartree–Fock (MP2 and CCSD(T)) methods with range of basis sets 6‐31G(d), cc‐pVXZ (X = D, T, Q) and aug‐cc‐pVYZ (Y = D, T). Three stable structures are considered on the potential energy surface of formamide and water system. The optimized geometric parameters and interaction energies for various isomers at different levels are estimated. The IR frequencies, intensities, and frequency shifts are reported. This study shows that B3LYP/aug‐cc‐pVDZ method gives better performance for formamide‐water complexes. © 2009 Wiley Periodicals, Inc. Int J Quantum Chem, 2010. 相似文献
92.
Enantiospecific first total synthesis of the angular triquinane sesquiterpene (6S,7R)-silphiperfolan-6-ol has been accomplished, starting from 2-(3-isopropenyl-2-methylene-1-methylcyclopent-1-yl)acetic acid (readily available from (R)-limonene) employing an efficient, regioselective intramolecular rhodium carbenoid insertion into the CH bond of a tertiary methyl group as the key step. 相似文献
93.
Dr. Ganganagappa Nagaraju 《无机化学与普通化学杂志》2012,638(14):2286-2291
A simple low temperature hydrothermal method was found to yield Na0.28V2O5 nanobelts after two days at 130 °C in acidic medium (H2SO4) without using any surfactant. The obtained products were characterized by X‐ray diffraction (XRD), Fourier transform infrared spectroscopy (FT‐IR), and Raman spectroscopy. Their morphology was investigated by scanning electron microscopy (SEM) and transmission electron microscopy (TEM). Additionally, their electrochemical behavior in a lithium battery was investigated. The XRD pattern shows that the product is composed of monoclinic Na0.28V2O5 nanobelts. From the FTIR spectrum, the band centered at 961 cm–1 is assigned to V=O stretching vibration, which is sensitive to intercalation and suggests that Na+ ions are inserted between the vanadium oxide layers. SEM/TEM analyses reveal that the products consist of a large quantity of nanobelts which have a thickness of 60–150 nm and a length of several tens of micrometers. The electrochemical results show that the nanobelts exhibit an initial discharge specific capacity of 390 mAh · g–1, and its stabilized capacity still remained around 200 mAh · g–1 after the 18th cycle. 相似文献
94.
Stereoselective synthesis of Baylis-Hillman-type adducts via allenolates generated by acyl migration
[reaction: see text] The rearrangement of the carbamoyl group in allenyl carbamate 1 in the presence of n-BuLi in situ generates the allenolate 3, which is subsequently intercepted with aromatic aldehydes furnishing (Z)- or (E)-configured Baylis-Hillman-type adducts 4 or 5. The double bond isomers can be interconverted by a retro aldol-type reaction. 相似文献
95.
Dhananjay Satyendra Singh J. Nagaraju S.B. Krupanidhi 《Applied Physics A: Materials Science & Processing》2007,88(2):421-424
Sol–gel route was employed to grow polycrystalline thin films of Li-doped ZnO thin films (Zn1-xLixO, x=0.15). Polycrystalline films were obtained at a growth temperature of 400–500 °C. Ferroelectricity in Zn0.85Li0.15O was verified by examining the temperature variation of the real and imaginary parts of dielectric constant, and from the
C–V measurements. The phase transition temperature was found to be 330 K. The room-temperature dielectric constant and dissipation
factor were 15.5 and 0.09 respectively, at a frequency of 100 kHz. The films exhibited well-defined hysteresis loop, and the
values of spontaneous polarization (Ps) and coercive field were 0.15 μC/cm2 and 20 kV/cm, respectively, confirming the presence of ferroelectricity.
PACS 77.22Ch; 77.22Ej; 77.80Bh 相似文献
96.
Nagaraju Madala Venkata Rao Ghanta Srilalitha Vinnakota Narender Mendu Arun B. Ingle Krishna Ethiraj Vishal Sharma 《Tetrahedron letters》2018,59(27):2708-2710
A synthetic strategy was developed for the synthesis of the common core structure of Carpatamides A–D. The total synthesis of Carpatamides A and C was completed in 6 steps and of Carpatamides B and D in 7 steps, by employing the Wittig olefination, olefin cross metathesis and acid amine coupling reactions as key steps. 相似文献
97.
We demonstrate radial p-n junction silicon solar cells with micro-pillar array with higher short-circuit current and open-circuit voltage than comparable planar silicon solar cells. Micro-pillar array, fabricated by RIE, acts as an effective anti-reflection coating for visible light with less than 6% reflection. Compared to devices with planar surface, devices with micro-pillar array show a 27% enhancement in short circuit current. The radial p-n junction of the micro-pillars also improves extraction probability of the photogenerated carriers, which further increases the short circuit current. Typically, micro-pillar solar cells suffer from high recombination losses at the Si/metal interface, resulting in poor VOC. Our devices prevent these recombination losses by planarizing the Si/metal interface, leading to an open circuit voltage of 622?mV, the highest ever reported for micro-pillar solar cells. This planarized contact also reduces the series resistance associated with radial junctions, leading to series resistance of ≤0.50?Ω-cm2 and fill factors up to 76.7%. 相似文献
98.
Shreenivasa L. Prashanth S. A. Eranjaneya H. Viswanatha R. Yogesh K. Nagaraju G. Ashoka S. 《Journal of Solid State Electrochemistry》2019,23(4):1201-1209
Journal of Solid State Electrochemistry - The performance of the cathode materials can be enhanced significantly by manipulating the surface properties through a nano-structuring. Porous ZrV2O7 is... 相似文献
99.
Kerru Nagaraju Bhaskaruni Sandeep V. H. S. Gummidi Lalitha Maddila Surya Narayana Singh Parvesh Jonnalagadda Sreekantha B. 《Molecular diversity》2020,24(2):345-354
Molecular Diversity - The Bi2O3 loading on ZrO2 as heterogeneous catalyst was established as an extremely efficient catalyst for the synthesis of a series of novel... 相似文献
100.
Molecular Diversity - Antimicrobial resistance has become a significant threat to global public health, thus precipitating an exigent need for new drugs with improved therapeutic efficacy. In this... 相似文献