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51.
Pandey A. Khan F. A. Kelkar A. Purohit P. Kumar Pradeep Sathe D. B. Bhatt R. B. Behere P. G. 《Journal of Radioanalytical and Nuclear Chemistry》2020,323(2):731-740
Journal of Radioanalytical and Nuclear Chemistry - 149Tb, 152Tb, 155Tb and 161Tb can cover all the modalities of diagnostic and therapeutic purposes of nuclear medicine. The production cross... 相似文献
52.
Leonard I. Wassenaar Liang-Feng Han Thomas Schiefer Gustav Kainz Luis Araguas-Araguas Pradeep K. Aggarwal 《Isotopes in environmental and health studies》2018,54(3):274-287
Tritium (3H) is an essential tracer of the Earth's water cycle; yet widespread adoption of tritium in hydrologic studies remains a challenge because of analytical barriers to quantification and detection of 3H by electrolytic pre-concentration. Here, we propose a simple tritium electrolytic enrichment system based on the use of solid polymer electrolyte membranes (PEMs) that can be used to enrich 3H in 250–3000?mL environmental water samples to a 10-mL final volume. The IAEA PEM-3H system reported here can produce high enrichment factors (>70-fold) and, importantly, removes some of the deterrents to conventional 3H enrichments methods, including the use of toxic electrolysis and neutralization chemicals, spike standards, a complex electrolysis apparatus that requires extensive cooling and temperature controls, and improves precision by eliminating the need for tracking recovery gravimetrics. Preliminary results with varying operating conditions show 3H enrichments to 70-fold and higher are feasible, spanning a wide range of tritium activities from 5 to 150 TU with a precision of ~4.5?%. Further work is needed to quantify inter-sample memory and to establish lower 3H detection limits. The IAEA PEM-3H system is open source, with 3-D CAD and design files made freely available for adoption and improvement by others. 相似文献
53.
Pradeep Kumar 《Phase Transitions》2015,88(6):605-620
A comparative study of two different particle sizes of ferroelectric barium titanate (BaTiO3) nanoparticles as a dopant on the molecular structure, spontaneous polarization and dielectric behavior of a pure ferroelectric liquid crystal 6F6T have been studied. It has been found that there is a remarkable decrease in isotropic temperature of both doped samples as compared to the pure 6F6T sample. The spontaneous polarization also decreases for both the doped samples and the reduction is more pronounced in case of the dopant with large particle size. The dielectric spectroscopy confirms the presence of soft mode as well as Goldstone mode and also shows the decrease in the value of dielectric permittivity ?' as a function of frequency for both doped samples. The improvised properties of liquid crystal host doped with BaTiO3 nanoparticles mainly depend upon the synthesis method of nanoparticles and also upon the particle size of dopant. 相似文献
54.
We discuss the notion of spin squeezing considering two mutually exclusive classes of spin-s states, namely, oriented and non-oriented states. Our analysis shows that the oriented states are not squeezed while non-oriented
states exhibit squeezing. We also present a new scheme for construction of spin-s states using 2s spinors oriented along different axes. Taking the case of s=1, we show that the ‘non-oriented’ nature and hence squeezing arise from the intrinsic quantum correlations that exist among
the spinors in the coupled state. 相似文献
55.
Ramachandran K. Tripathi V.K. 《IEEE transactions on plasma science. IEEE Nuclear and Plasma Sciences Society》1998,26(2):141-144
Near the critical layer, a large-amplitude laser beam creates a transverse plasma channel due to the ponderomotive force. The axis of the channel is normal to the ambient density gradient. Inside the channel, the laser beam decays into counter-propagating ion acoustic and Langmuir waves. A nonlocal theory of the process is developed for a parabolic density profile. The growth rate of the instability is significantly reduced due to the nonlocal effects 相似文献
56.
C. Pradeep S. Mathew B. Nithyaja P. Radhakrishnan V. P. N. Nampoori 《Applied Physics A: Materials Science & Processing》2014,115(1):291-295
In this paper we study the nonlinear optical properties of PicoGreen dye. The investigations involve the single-beam Z-scan technique and measurements were carried out at different incident intensities. Both open and closed aperture Z-scan techniques were performed at 532 nm and it was found that the dye exhibited a reverse saturable absorption with significant nonlinear absorption coefficient and intensity-dependent negative nonlinear refraction coefficient, indicating self-defocusing phenomena. The third-order nonlinear susceptibility and optical limiting threshold were also measured. 相似文献
57.
The diacetylenic adducts, Fe2(CO)6{-EC(H) = C(C CMe)E} (E = E, E E; E, E = S, Se, Te) (1–8) have been obtained from the room temperature stirring of Fe2(CO)6(-EE) with HC CC CMe in methanol solvent containing sodium acetate. Compounds 1–8 have been characterized by IR and multinuclear NMR (1H, 13C, 77Se, and l25Te) spectroscopy. Trends in the chemical shifts of 77Se and 125Te NMR spectra of Fe2(CO)6{-EC(H) = C(C CMe)E} with a variation of EE are discussed. 相似文献
58.
Liaoliao Wang Meixiang Cen Dr. Sherif A. El-Khodary Dr. K. Ramachandran Jinning Huang Dr. Yingxue Cui Prof. Dr. Dickon H. L. Ng Prof. Dr. Chuan Wang Prof. Dr. Jiabiao Lian 《Chemistry (Weinheim an der Bergstrasse, Germany)》2022,28(68):e202202358
Surface oxygen functionalities (particularly C−O configuration) in carbon materials have negative influence on their electrical conductivity and Na+ storage performance. Herein, we propose a concept from surface chemistry to regulate the oxygen configuration in hierarchically porous carbon nanosheets (HPCNS). It is demonstrated that the C−O/C=O ratio in HPCNS reduces from 1.49 to 0.43 and its graphitization degree increases by increasing the carbonization temperature under a reduction atmosphere. Remarkably, such high graphitization degree and low C−O content of the HPCNS-800 are favorable for promoting its electron/ion transfer kinetics, thus endowing it with high-rate (323.6 mAh g−1 at 0.05 A g−1 and 138.5 mAh g−1 at 20.0 A g−1) and durable (96 % capacity retention over 5700 cycles at 10.0 A g−1) Na+ storage performance. This work permits the optimization of heteroatom configurations in carbon for superior Na+ storage. 相似文献
59.
Chockalingam Karunakaran Kaliyaperumal Anandhy Velusamy Ramachandran 《Monatshefte für Chemie / Chemical Monthly》2000,34(2):1025-1029
Upon aging, perborate in glacial acetic acid generates peracetic acid and thus oxidizes S-phenylmercaptoacetic acid rapidly. Perborate dissolved in ethylene glycol, however, does not show the aging effect, and the corresponding oxidation proceeds smoothly. The oxidation is of second order and not acid catalyzed. Boric acid and borate do not influence the oxidation. In the smooth oxidation, is the reactive species. The oxidation of some para-substituted S-phenylmercaptoacetic acids conforms to the Exner relationship, indicating operation of a common mechanism. Also, the oxidation obeys the Hammett equation with a negative reaction constant. However, the oxidation of p-nitro-S-phenylmercaptoacetic acid follows a different kinetic pathway. 相似文献
60.
Dr. Pradeep Chopra Dr. Tejabhiram Yadavalli Francesco Palmieri Dr. Seino A. K. Jongkees Dr. Luca Unione Prof. Dr. Deepak Shukla Prof. Dr. Geert-Jan Boons 《Angewandte Chemie (International ed. in English)》2023,62(41):e202309838
Herpes simplex virus (HSV-1) employs heparan sulfate (HS) as receptor for cell attachment and entry. During late-stage infection, the virus induces the upregulation of human heparanase (Hpse) to remove cell surface HS allowing viral spread. We hypothesized that inhibition of Hpse will prevent viral release thereby representing a new therapeutic strategy for HSV-1. A range of HS-oligosaccharides was prepared to examine the importance of chain length and 2-O-sulfation of iduronic moieties for Hpse inhibition. It was found that hexa- and octasaccharides potently inhibited the enzyme and that 2-O-sulfation of iduronic acid is tolerated. Computational studies provided a rationale for the observed structure–activity relationship. Treatment of human corneal epithelial cells (HCEs) infected with HSV-1 with the hexa- and octasaccharide blocked viral induced shedding of HS which significantly reduced spread of virions. The compounds also inhibited migration and proliferation of immortalized HCEs thereby providing additional therapeutic properties. 相似文献