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321.
Toshikatsu Koga Tomomi Tanabe Ajit J. Thakkar 《International journal of quantum chemistry》1997,63(2):287-290
Configuration interaction (CI) calculations are carried out for the ground state of lithium using a thoroughly optimized basis set of s-type Slater functions. They establish that the radial limit of the nonrelativistic energy of the ground 2S state of lithium is no higher than −7.448666443Eh. Thus, radial correlation accounts for 35.2% of the total correlation energy. The radial CI wave function predicts a significantly more accurate Fermi contact parameter than the Hartree-Fock wave function. However, the imbalanced treatment of electron correlation in the radial CI wave function leads to an excessively diffuse electron density that is worse than that of the Hartree-Fock wave function. © 1997 John Wiley & Sons, Inc. 相似文献
322.
Geetanjali Mishra Barsha Dash Ajit Dash I.N. Bhattacharya 《Crystal Research and Technology》2016,51(7):433-440
Mesoporous Al2O3 were positively synthesized via treatment of the freshly precipitated amorphous alumina gel using aluminium sulphate as aluminium source, and sodium dodecyl sulphate (SDS) as structure‐directing agent (SDAs). The microstructures, morphologies and textural properties of the as‐prepared materials were characterized by X‐ray diffraction (XRD), transmission electron microscopy (TEM) and thermo gravimetric analysis (TG‐DTA). The calcined product at 600 °C was highly porous in nature having a BET surface area of 42 m2/g. These porous Al2O3 exhibits excellent adsorption performance for Congo red and the corresponding decolourisation efficiencies reached 99% in just 15 min at 27 °C. The subsequent calcined product at 1200 °C is the alpha alumina single crystal hexagonal platelets with rhombohedral crystallization. 相似文献
323.
Rishabh Sharma Manika Khanuja S. S. Islam Uma Singhal Ajit Varma 《Research on Chemical Intermediates》2017,43(10):5345-5364
The photo-antimicrobial and photocatalytic performance of ZnO nanorods as a function of aspect ratio are presented. The antibacterial activity of the synthesized ZnO nanorod samples against Gram-negative and Gram-positive bacteria (Staphylococcus aureus and Escherichia coli, respectively) was determined by shake flask method with respect to time. ZnO nanorods with high aspect ratio showed superior antimicrobial and photocatalytic activity. These results are supported by X-ray diffraction, transmission electron microscopy, scanning electron microscopy, ultraviolet–visible (UV–Vis) spectroscopy, photoluminescence, and Brunauer–Emmett–Teller (BET) studies. Degradation of methylene blue dye as model organic pollutant was used to assess their photocatalytic activity. Pseudo-first-order rate kinetics was used to calculate the photocatalytic reaction rate constant. The mechanisms for both antimicrobial and photocatalytic activity are elucidated. 相似文献
324.
Tapas Das Mohini Bhadwal Sharmila Banerjee H. D. Sarma Ajit Shinto K. K. Kamaleshwaran 《Journal of Radioanalytical and Nuclear Chemistry》2014,299(3):1389-1398
The objective of the present work is to prepare freeze-dried DOTA-TATE and DOTA-NOC kits for the easy and convenient preparation of patient doses of 177Lu-DOTA-TATE and 177Lu-DOTA-NOC, respectively at the hospital radiopharmacy and to compare the radio-peptides with respect to their radiochemical and biological behaviors. Freeze-dried kits of DOTA-TATE and DOTA-NOC, comprising a lyophilized mixture of 200 μg of DOTA-peptide, 80 mg of gentisic acid and 13.9 mg of ammonium acetate were prepared. Therapeutic doses of 177Lu-labeled peptides (up to 200 mCi, 7.4 GBq) were prepared using these kits and 177Lu, produced in-house, with >99 % radiochemical purity and high stability following an easy and convenient protocol. Comparative pharmacokinetic behavior of the radio-peptides was studied by carrying out biodistribution studies in normal Wistar rats which revealed higher retention of activity in several major organs and slower renal clearance for 177Lu-DOTA-NOC compared to that of 177Lu-DOTA-TATE. Preliminary pharmacokinetic studies, carried out in limited number of patients suffering from cancers of neuroendocrine origins, showed lower accumulation of activity in vital organs and faster renal clearance of 177Lu-DOTA-TATE compared to that of 177Lu-DOTA-NOC. 相似文献
325.
Development of a portable shear test fixture for low modulus porous (foam) materials 总被引:2,自引:0,他引:2
The shear properties of brittle and highly porous carbon (graphitic) foam cannot be measured reliably with most standard test
methods, such as single rail, double rail, Iosipescu shear, etc. A new testing device has been developed to accurately measure
the shear stiffness and strength of carbon foam or other porous materials. Specimens of cylindrical cross section are used
to reduce the high stress concentration that normally occurs in the vicinity of the grip section. Since strain gages could
not be installed on the specimen surface (due to porosity), the shear strain is determined from the specimen end rotation.
A high resolution in the rotational measurement is achieved by using a stepper motor with multiple gear reduction. In view
of testing low modulus material, the load cell of the fixture was mounted onto an axial roller to relieve the axial constraint
while twisting the specimens. The accuracy of the measurement and calibration of the test fixture has been demonstrated by
measuring the shear modulus of two plastic (polyvinyl chloride (PVC) and urethane). 相似文献
326.
Mukund G. Kulkarni Saryu I. Davawala Mahadev P. Shinde Attrimuni P. Dhondge Ajit S. Borhade Sanjay W. Chavhan Dnyaneshwar D. Gaikwad 《Tetrahedron letters》2006,47(18):3027-3029
A Wittig olefination-Claisen rearrangement strategy has been applied to achieve one of the shortest and efficient synthesis of (±)-β-cuparenone. 相似文献
327.
Ajit Kumar Indra Sen Ram Sunil Kumar Jagjiwan Ram A. N. Upadhyay Kedar Singh 《Journal of Thermal Analysis and Calorimetry》2018,134(2):923-931
Glassy Se100?x(Ge2Sb2Te5)x (x?=?5, 10, 15 and 20) bulk alloys were prepared by melt-quenched technique and studied by using differential scanning calorimetry at different heating rates under non-isothermal condition. The detailed thermal analysis shows that the glass transition temperature (Tg) depends on heating rates and x content. In particular, it is found that the glass-forming ability, thermal stability (Tc???Tg) and crystallization activation energy (Ec) increase with increased x content in amorphous Se, whereas glass transition activation energy (Eg) and fragility index (F) decrease with increased x contents. Variation in these parameters can be explained on the basis of network-forming ability of Se and bonding arrangement among the constituent atoms of alloys. 相似文献
328.
Chakraborty TK Koley D Ravi R Krishnakumari V Nagaraj R Kunwar AC 《The Journal of organic chemistry》2008,73(22):8731-8744
Sugar amino acid based 24-membered macrocyclic C2-symmetric cationic peptides were designed and synthesized. The cationic group was introduced in the sugar amino acids. The conformation of these cyclic compounds was ascertained through NMR techniques, which proved they were amphipathic in nature. All the compounds were bacteriolytic, showed good activity against the Gr(+ve) and Gr(-ve) bacteria, and exhibited low hemolytic activity. 相似文献
329.
An efficient conversion of artemisinin 1 into three new amino- and hydroxy-functionalized 11-aza prototypes 9, 11, and 12 has been achieved on a multigram scale by reaction with hydrazine, hydroxylamine, and 2-amino ethanol, respectively. Of these, 9 has been further diversified into a wide range of derivatives including imines, amines, amides, and linker based dimers. Prototypes 11 and 12 have been converted into the corresponding ethers in high yields. Some of these compounds have shown a high order of activity against multidrug-resistant malaria in mice by oral route. 相似文献
330.
Efficient chemoenzymatic synthesis of biotinylated human serum albumin-sialoglycoside conjugates containing O-acetylated sialic acids 总被引:1,自引:0,他引:1
Sialyl Tn (STn) and sialyl lactoside derivatives containing O-acetylated sialic acid residues have been chemoenzymatically synthesized using a one-pot three-enzyme system and conjugated to biotinylated human serum albumin (HSA) using an adipic acid para-nitrophenyl ester coupling reagent. This approach provides an efficient and general protocol for preparing carbohydrate-protein conjugates containing base-sensitive groups. 相似文献