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991.
992.
In Japan, large amounts of fertilizer nitrogen are applied to tea plantations. We collected samples of tea plantation soil each season for a year. Samples were analyzed for their contents of various inorganic chemicals and total N. Nitrogen was present mainly in the top 0 to 30?cm of soil. However, at times the concentration of nitrate N in the soil water was more than 35?mg?L?1, even in the deepest layers. The contents of various metal elements in the soil were examined. Ba, Fe, Sr and Zn contents were high in the top 0 to 30?cm of soil. But Al and Mn contents were not always high in the top 0 to 30?cm of soil. From the correlation analysis among contents of various inorganic chemicals, it was suggested that increased leaching of Al, Mn, and Zn from tea plantation soil occurred with increased nitrate N concentration.  相似文献   
993.
994.
Journal of Solid State Electrochemistry - Xanthan gum (XG)-based hydrogels containing sodium hydroxide (NaOH) salt were synthesized with the use of distilled water (DW) at room temperature and...  相似文献   
995.
Abstract

An analytical model is proposed to analyze the vibration and buckling problem of partially cracked thin orthotropic microplate in the presence of thermal environment. The differential governing equation for the cracked plate is derived using the classical plate theory in conjunction with the strain gradient theory of elasticity. The crack is modeled using appropriate crack compliance coefficients based on the simplified line spring model. The influence of thermal environment is incorporated in governing equation in form thermal moments and in-plane compressive forces. The governing equation for cracked plate has been solved analytically to get fundamental frequency and central deflection of plate. To demonstrate the accuracy of the present model, few comparison studies are carried out with the published literature. The stability and dynamic characteristics of the cracked plate are studied considering various parameters such as crack length, plate thickness, change in temperature, and internal length scale of microstructure. It has been concluded that the frequency and deflection are affected by crack length, temperature, and internal length scale of microstructure. Furthermore, to study the buckling behavior of cracked plate, the classical relations for critical buckling load and critical buckling temperature is also proposed considering the effect of crack length, temperature, and internal length scale of microstructure.  相似文献   
996.
QSPR analysis of flash points.   总被引:5,自引:0,他引:5  
  相似文献   
997.
IntroductionThemeasurementofshearstressinarterialflowhasbeenbestowedbynaturebecauseofthepossiblerelationbetweentheshearstressatthewallandexistenceofatherosclerosis.Theflowphenomenainlargeandmediumsizedarteriesinfluencethedevelopmentofatherosclerosicd…  相似文献   
998.
In most high energy radiation fields, such as those encountered around accelerators or cosmic rays in the atmosphere, neutrons produce the largest percentage of the hadron dose. In these radiation fields, the neutron spectrum is typically formed by low energy neutrons (evaporation spectrum) and high energy neutrons (knock-on spectrum).

Neutron spectrometry and dosimetry are better understood for low energy neutrons (i.e. neutrons with energy below 20 MeV) than for those of higher energies. This paper reports the study of different detectors based on the registration of fission fragments of different heavy elements (namely bismuth, gold and tantalum), which have their principal response to high energy neutrons.  相似文献   

999.
Sudhir R Jain 《Pramana》2001,57(2-3):571-584
Nuclei have complex energy-level sequence with statistical properties in agreement with canonical random matrix theory. This agreement appears when the one-particle one-hole states are mixed completely with two-particle two-hole states. In the transition, there is a new universality which we present here, bringing about a relation between dynamics and statistics. We summarize also the role of chaos in thermalization and dissipation in isolated systems like nuclei. The methods used to bring forth this understanding emerge from random matrix theory, semiclassical physics, and the theory of dynamical systems.  相似文献   
1000.
A new bridgehead nitrogen hetero‐ cycle viz. 11‐carboethoxy‐9‐oxo‐pyrimido[3′2′:3,4]‐1,2,4‐triazino[5,6‐b]indole 3 has been synthesized from 3‐azido‐5H‐1,2,4‐triazino[5,6‐b]indole 2 by its reaction with diethyl fumerate. The intermediate 2 was obtained by treating 3‐hydrazino‐5H‐1,2,4‐triazino[5,6‐b]indole with NaNO2 in presence of polyphosphoric acid. A plausible mechanism for the formation of 3 has been formulated and discussed. © 2006 Wiley Periodicals, Inc. Heteroatom Chem 17:272–276, 2006; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/hc.20199  相似文献   
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