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31.
Md. Arzoo Ansari U. K. Sinha Archana Deodhar G. N. Mendhekar Mukund Kumar S. D. Patbhaje Ashutosh Dash 《Journal of Radioanalytical and Nuclear Chemistry》2017,313(3):617-623
Isotopic investigations were carried out on hot springs, groundwater and surface water to evaluate the mixing processes within the geothermal system. Physico-chemical parameter (EC, pH, Temp.) and tritium content of groundwater, hot springs and surface water were measured. The temperature of the hot springs were varied from 60 to 98.8 °C and EC from 674 to 728 μS/cm. The tritium content of groundwater varies from 1.5 to 5 TU whereas, geothermal water have slightly less tritium and their values ranges from 1.4 to 4.4 TU. Low tritium, higher EC and high temperature of a few hot springs indicate insignificant mixing whereas high tritium, lower EC and low temperature indicates significant mixing of thermal and non-thermal water. The degree of mixing for geothermal springs is estimated. It is found that the groundwater components present in the diluted thermal waters are about 25–80%. It is also observed that mixing process is prominent along the fault and in the area where groundwater exploitation is more. Extensive pumping of groundwater causes an increase in the rate of mixing of thermal and non-thermal water. The tritium content of groundwater, surface water and hot springs are indicating, it is of modern recharge. 相似文献
32.
Mishra A. Jahan CS A. Kesarwani S. Raval H. Kumar S. Meena J. 《The European Physical Journal A - Hadrons and Nuclei》2019,55(6):1-8
The European Physical Journal A - In this paper, we investigated the spectroscopy of heavy tetraquarks through a relativistic diquark-antidiquark model. To this aim, the two-bosonic Klein-Gordon... 相似文献
33.
GYÖRGY TARCZAY ATTILA G. CSÁSZÁR WIM KLOPPER HARRY M. QUINEY 《Molecular physics》2013,111(21):1769-1794
Relativistic energy corrections which arise from the use of the Dirac-Coulomb Hamiltonian, and the Gaunt and Breit interaction operators, plus Lamb-shift effects have been determined for the global minima of the ground electronic states of C2H6, NH3, H2O, [H,C,N], HNCO, HCOOH, SiC2, SiH? 3, and H2S, and for barrier characteristics for these molecular systems (inversion barrier of NH3 and SiH? 3, barrier to linearity of H2O, H2S, and HNCO, rotational barrier of C2H6, difference between conformations of HCOOH (Z/E) and SiC2 (linear/T-shaped), and isomerization barrier of HCN/HNC). The relativistic calculations performed at the Hartree-Fock and the highly correlated CCSD(T) levels employed a wide variety of basis sets. Comparison of the perturbational and the four-component fully variational results indicate that the Coulomb-Pauli Hamiltonian and the lowest order Hamiltonian of direct perturbation theory (DPT(2)) are highly successful for treating the relativistic energy effects in light molecular systems both at a single point on the potential energy hypersurface and along the surface. Electron correlation contributions to the relativistic corrections are relatively small for the systems studied, and are comparable with the 2-electron Darwin correction. Corrections beyond the Dirac-Coulomb treatment are usually rather small, but may become important for high accuracy ab initio calculations. 相似文献
34.
We present evidence for a nonsingular origin of the Universe with intial conditions determined by quantum physics and relativistic
gravity. In particular, we establish that the present temperature of the microwave background and the present density of the
Universe agree well with our predictions from these intial conditions, after evolution to the present age using the Einstein-Friedmann
equation. Remarkably, the quantum origin for the Universe naturally allows its evolution at exactly the critical density.
We also discuss the consequences of these results to some fundamental aspects of quantum physics in the early Universe. 相似文献
35.
36.
- 1.A critical examination of the existing data on X-ray satellite spectra has led to a fuller information regarding the occurrence of pairs of satellite lines in theK, L andM regions, showing more or less constant value ofΔ√ν/R, similar to the screening doublets in the X-ray energy levels of singly ionised atoms. 相似文献
37.
Willard M Freeman Melinda E Lull Kruti M Patel Robert M Brucklacher Drake Morgan David CS Roberts Kent E Vrana 《BMC neuroscience》2010,11(1):29
Background
Many studies of cocaine-responsive gene expression have focused on changes occurring during cocaine exposure, but few studies have examined the persistence of these changes with cocaine abstinence. Persistent changes in gene expression, as well as alterations induced during abstinence may underlie long-lasting drug craving and relapse liability. 相似文献38.
An emission spectrographic method using carrier distillation for the determination of the refractory impurities Ta, Hf, Nb, Th, and W in uranium is described. Different carriers, such as Ga2O3, AgCl, AgCl + LiF, and AgCl + NaF in various proportions, were investigated: a 1% NaF + 9% AgCl mixture as carrier at 10% of total charge arced was found to be the most suitable. Spectra were excited in a d.c. arc at 12 A and were photographed with 35-sec exposures. Palladium was used as an internal standard. The lowest limits of determination lie in the range 1–10 ppm for a 100-mg charge. The precision of the method is about 16% or better. 相似文献
39.
An emission spectrographic method for the estimation of rare-earth impurities in plutonium oxide and the mixed oxide (U,Pu)O(2) (30% PuO(2)-70% UO(2)) has been developed. Rare-earth impurities are separated from the matrix by solvent extraction with tri-n-octylamine in xylene and are estimated after concentration. Thulium is used as internal standard and LiF-AgCl as carrier. The spectra are excited in a d.c. arc. The detection limits lie in the range 0.004-0.1 mug and the coefficient of variation ranges from 5 to 23%. 相似文献
40.
W. Meisel CS. Vértes M. Lakatos-Varsányi 《Journal of Radioanalytical and Nuclear Chemistry》1995,190(2):289-298
Integral electron Mössbauer spectroscopy (ICEMS) and additionally some electrochemical methods were used to characterize the passivation process of iron (low carbon steel) in sulfate, sulfate+sulfite (a possible model solution of acid rain) solutions and in phospate buffer. The phase compositions and thicknesses of the passive layers formed due to the electrochemical polarizations were analyzed in dependence on the duration of the anodic passivations and on the pH of the used electrolytes. The passive layer, as determined from the Mössbauer spectra, consists mainly of -FeOOH, however in sulfite containing sulfate aqueous solution at pH 3.5 Fe3C and despite ex-situ circumstances FeSO4·H2O was detected after the shortest polarization time. The film thickness, which was found to grow nearly linearly with polarization time in pure sulfate solution and in phospate buffer, reached a maximum of 60–160 nm (depending on pH) in sulfate+sulfite solution after a passivation time of about 4 hours. It has been proved, that HSO3
–-ion, which is contained by acid rain, initiate pit formation under acid conditions and so enforces the corrosion of iron. The experimental results furthermore suggest, that not the whole oxidic layer is responsible for the passivity but only a very thin intermediate layer formed between an inner oxide layer of a cubic structure and the rhombic oxide (-FeOOH) cover. 相似文献