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361.
G. Madhurambal N. Prabha S. P. Lakshmi S. C. Mojumdar 《Journal of Thermal Analysis and Calorimetry》2013,112(2):1067-1075
Various crystals are seen in human urine. Oxalate, Phosphate, Uric acid, and Urate crystals are generally seen in urinary calculi. Calcium stones are most common, comprising 75 % of all urinary calculi. They may be pure calcium oxalate or calcium phosphate or a mixture of both. Many stones are not homogeneous. Low calcium intake increases the intestinal absorption of calcium, thus decreasing the amount of calcium available in the intestinal tract to form insoluble complexes with Oxalate. Consequently, a higher amount of oxalate is available for intestinal absorption and as a result, urinary oxalate excretion increases. Mineral water consumption did not reduce urinary oxalate excretion. High urinary excretion and concentration of magnesium decrease both the nucleation and growth rates of calcium oxalate crystals in urine, because of the higher solubility of magnesium oxalate compared with calcium oxalate. Analytical results show calcium oxalate to be one of the major inorganic components of renal stones and found to be present in almost all kidney and bladder stones. About 39.5 % of the total composition of the calculi is found to contain purely calcium oxalate and also hydroxyl apatite. The ten samples are a mixture of calcium oxalate and phosphate stones. Four samples are calcium oxalate as major composition and the remaining are calcium phosphate as major composition. These kidney stones are taken photographically and size of the stone are measured using optical microscopy. These qualitative analyses are also confirmed by UV, FTIR, DSC, and XRD analysis. 相似文献
362.
Rubel Chakravarty Meera Venkatesh Ashutosh Dash 《Journal of Radioanalytical and Nuclear Chemistry》2011,290(1):45-51
A novel electrochemical process to avail clinical grade 99mTc from (n,γ)99Mo has been demonstrated. The electrochemical parameters were optimized to maximize the 99mTc yield with minimal 99Mo contamination. 99Mo/99mTc generators containing up to 29.6 GBq (800 mCi) 99Mo were developed and their performance were extensively evaluated for 10 days without changing the operating conditions.
Very high radioactive concentration of 99mTcO4
− of acceptable quality, commensurate with hospital radiopharmacy requirements could be availed from the system with >90% yield.
The compatibility of the product for the formulation of 99mTc labeled radiopharmaceuticals such as 99mTc-DMSA and 99mTc-EC was found to be satisfactory in terms of high labeling yields. The proposed route represents an important step for enhancing
the scope of accessing clinical grade 99mTc from low specific activity (n, γ)99Mo. 相似文献
363.
K. V. Vimalnath A. Rajeswari Viju Chirayil P. L. Sharad K. C. Jagadeesan P. V. Joshi Meera Venkatesh 《Journal of Radioanalytical and Nuclear Chemistry》2011,290(1):221-225
64Cu (t1/2 12.7 h) is a versatile radionuclide owing to its unique decay scheme and exhibits three types of decay electron capture (41%),
β− (40%), β+ (19%) that is useful in nuclear medicine applications. Different batches of natural copper oxide (CuO) and 99.9% enriched
63CuO targets were irradiated in research reactors at a neutron flux of 6.6 × 1012 n cm−2 s−1 for duration of 3 days. Irradiated samples dissolved in hydrochloric acid solution were measured in HPGe-MCA system, the
activity of 64Cu, co-produced radionuclide impurities and radionuclide purity was determined. Average specific activity of 254 GBq 64Cu per g Cu and ~348 GBq 64Cu per g Cu was recorded at the end of irradiation from natural and enriched CuO targets, respectively. 相似文献
364.
Nitin Kumar Dr. Rapelly Venkatesh Prof. Sundaram Singh Prof. Jeyakumar Kandasamy 《European journal of organic chemistry》2023,26(37):e202300679
An efficient and eco-friendly method has been developed for the preparation of functionalized 3-(S)-arylthioindoles in good to excellent yields from indoles and aryl thiols in water. The coupling reaction was prompted by K2S2O8 in the presence of glucose at room temperature. Broad substrate scope, functional group tolerance, room temperature reactions and metal-free conditions are the salient features of the developed methodology. 相似文献
365.
Xinlin Li Sreehari Surendran Rajasree Dr. Venkatesh Gude Karan Maindan Prof. Dr. Pravas Deria 《Angewandte Chemie (International ed. in English)》2023,62(22):e202219046
Traditional MOF e-CRR, constructed from catalytic linkers, manifest a kinetic bottleneck during their multi-electron activation. Decoupling catalysis and charge transport can address such issues. Here, we build two MOF/e-CRR systems, CoPc@NU-1000 and TPP(Co)@NU-1000, by installing cobalt metalated phthalocyanine and tetraphenylporphyrin electrocatalysts within the redox active NU-1000 MOF. For CoPc@NU-1000, the e-CRR responsive CoI/0 potential is close to that of NU-1000 reduction compared to the TPP(Co)@NU-1000. Efficient charge delivery, defined by a higher diffusion (Dhop=4.1×10−12 cm2 s−1) and low charge-transport resistance ( =59.5 Ω) in CoPC@NU-1000 led FECO=80 %. In contrast, TPP(Co)@NU-1000 fared a poor FECO=24 % (Dhop=1.4×10−12 cm2 s−1 and =91.4 Ω). For such a decoupling strategy, careful choice of the host framework is critical in pairing up with the underlying electrochemical properties of the catalysts to facilitate the charge delivery for its activation. 相似文献
366.
Hazarika Jenasree Talukdar Anusuya Rajaraman Prasanna Venkatesh 《Journal of Solid State Electrochemistry》2023,27(4):895-909
Journal of Solid State Electrochemistry - The anodic dissolution of Cobalt in H2O2 solution is investigated in the presence and absence of a complexing agent, oxalic acid, using various techniques... 相似文献