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131.
Designs, Codes and Cryptography - A code is said to have locality r if any coordinate value in a codeword of that code can be recovered by at most r other coordinates. In this paper, we have... 相似文献
132.
Inside Back Cover: Cationic Metallo‐Polyelectrolytes for Robust Alkaline Anion‐Exchange Membranes (Angew. Chem. Int. Ed. 9/2018)
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133.
134.
135.
M. U. Rajput S. Ahmad M. Ahmad W. Ahmad 《Journal of Radioanalytical and Nuclear Chemistry》2005,266(2):343-348
Summary This study provides useful information about the level and chemical composition of particulate matter and about the possible
sources of the aerosol pollutant in Islamabad, the capital of Pakistan. Atmospheric aerosol samples were collected during
winter (January and February) 1995, from two locations of Islamabad, namely of Sector F-7 and Sector I-9. Twenty-four elements
were detected by using thermal neutron activation analysis (NAA) and atomic absorption spectrometry (AAS). The concentration
of total suspended particulates (TSP) in the area around the industrial sector (I-9) was found to be more than twice higher
(297 μg/m3) than in the Sector F-7 (133 μg/m3). The enrichment factor analysis revealed Zn, As, Br, Sb, I and Pb, originated mainly from anthropogenic sources. The elemental
ratio analysis indicated that both Sectors I-9 and F-7 are under the influence of coal burning processes whereas transportation
is responsible for the toxic pollutants Pb and Br. The present results were discussed and compared with those of the literature.
The results may also serve as base line level as this work employed samples collected in 1995 and many of the air environmental
change factors occurred after the sampling year. 相似文献
136.
Tianyu Zhu Dr. Shichao Xu Md. Anisur Rahman Dr. Emir Dogdibegovic Dr. Peng Yang Parasmani Pageni Mohammad Pabel Kabir Prof. Xiao‐dong Zhou Prof. Chuanbing Tang 《Angewandte Chemie (International ed. in English)》2018,57(9):2388-2392
Chemically inert, mechanically tough, cationic metallo‐polyelectrolytes were conceptualized and designed as durable anion‐exchange membranes (AEMs). Ring‐opening metathesis polymerization (ROMP) of cobaltocenium‐containing cyclooctene with triazole as the only linker group, followed by backbone hydrogenation, led to a new class of AEMs with a polyethylene‐like framework and alkaline‐stable cobaltocenium cation for ion transport. These AEMs exhibited excellent thermal, chemical and mechanical stability, as well as high ion conductivity. 相似文献
137.
Sarita Das Debi Prasad Das Priyanka Rajput Joydeep Ghosh Bhagyadhar Bhoi Barada Kanta Mishra 《Plasma Chemistry and Plasma Processing》2016,36(4):1125-1139
Out of many applications of hydrogen plasma, reduction of metal oxides is an important one. The reduction can be carried out using carbon or hydrogen. While carrying out the reduction of hematite (Fe2O3) in hydrogen plasma, an attempt was made to characterize the hydrogen plasma by optical emission spectroscopy. The spectroscopic results provide some new and useful information. In addition to the hydrogen emission lines, two prominent lines at 589 and 589.6 nm were observed. These two lines are confirmed to be sodium D1 and D2 (Na D lines) by comparing with a low pressure sodium vapour lamp (LPSVL). The source of the trace amount of sodium is also confirmed to be from the metal oxide sample as an impurity. These lines are found to be very sensitive to various process parameters such as gas flow rate, microwave power, and reduction chamber pressure. The temporal variation of these two Na D lines also shows a characteristic trend during metal oxide reduction in hydrogen plasma. The weight loss and the X-ray diffraction analyses of reduced Fe2O3 sample for different time duration provides the evidence of correlation with Na D lines’ intensity trend. This trend can be used to monitor the state and completion of hydrogen plasma based reduction reaction. In processes where Na is not associated with metal oxide, trace amount of Na in its molecular form such as NaOH can be introduced for monitoring the plasma process parameters as well as the plasma based reduction process. 相似文献
138.
Effect of gamma irradiation on X‐ray absorption and photoelectron spectroscopy of Nd‐doped phosphate glass
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V. N. Rai Parasmani Rajput S. N. Jha D. Bhattacharyya B. N. Raja Shekhar U. P. Deshpande T. Shripathi 《Journal of synchrotron radiation》2016,23(6):1424-1432
X‐ray absorption near‐edge structure (XANES) and X‐ray photoelectron spectroscopy (XPS) of Nd‐doped phosphate glasses have been studied before and after gamma irradiation. The intensity and the location of the white line peak of the L3‐edge XANES of Nd are found to be dependent on the ratio O/Nd in the glass matrix. Gamma irradiation changes the elemental concentration of atoms in the glass matrix, which affects the peak intensity of the white line due to changes in the covalence of the chemical bonds with Nd atoms in the glass (structural changes). Sharpening of the Nd 3d5/2 peak profile in XPS spectra indicates a deficiency of oxygen in the glasses after gamma irradiation, which is supported by energy‐dispersive X‐ray spectroscopy measurements. The ratio of non‐bridging oxygen to total oxygen in the glass after gamma radiation has been found to be correlated to the concentration of defects in the glass samples, which are responsible for its radiation resistance as well as for its coloration. 相似文献
139.
Ashwani Kumar C. Nayak P. Rajput R. K. Mishra D. Bhattacharyya C. P. Kaushik B. S. Tomar 《Hyperfine Interactions》2016,237(1):143
Gamma radiation induced changes in local structure around the probe atom (Hafnium) were investigated in sodium barium borosilicate (NBS) glass, used for immobilization of high level liquid waste generated from the reprocessing plant at Trombay, Mumbai. The (NBS) glass was doped with 181Hf as a probe for time differential perturbed angular correlation (TDPAC) spectroscopy studies, while for studies using extended X-ray absorption fine structure (EXAFS) spectroscopy, the same was doped with 0.5 and 2 % (mole %) hafnium oxide. The irradiated as well as un-irradiated glass samples were studied by TDPAC and EXAFS techniques to obtain information about the changes (if any) around the probe atom due to gamma irradiation. TDPAC spectra of unirradiated and irradiated glasses were similar and reminescent of amorphous materials, indicating negligible effect of gamma radiation on the microstructure around Hafnium probe atom, though the quaqdrupole interaction frequency (ω Q) and asymmetry parameter (η) did show a marginal decrease in the irradiated glass compared to that in the unirradiated glass. EXAFS measurements showed a slight decrease in the Hf-O bond distance upon gamma irradiation of Hf doped NBS glass indicating densification of the glass matrix, while the cordination number around hafnium remains unchanged. 相似文献
140.
Pratibha Nikhil Kumar Atul Kapoor Jaspreet Kaur Rajput Dinesh Singh Varnika 《Electroanalysis》2023,35(4):e202200283
Herein, an effective template assisted calcination procedure has been adopted to synthesize the Sulphur-doped graphitic carbon nitride (SXGCN). Furthermore, the SXGCN/GCE was then utilized for the electrochemical determination of 2,4-Dinitrophenol (2,4-DNP). It has been inferred that among the variously prepared SXGCN (x=0 %, 20 %, 40 %, 60 %, 80 %, and 100 %), S80GCN afforded the excellent electrochemical response for detection of 2,4-DNP. The synthesized SXGCN/GCE (x=80 %) demonstrates with a low detection limit of 0.9083 μM with linear range of 1–90 μM. Furthermore, the practical application of this sensor was successfully proved by detecting spiked 2,4-dinitrophenol in a real gym supplements sample. 相似文献