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321.
Sh. N. Jamal B.Sc. M.Sc. M. Z. Iqbal B.Sc. M.Sc. Ph.D. M. Athar M.Sc. M.Phil. Ph.D. D.Sc. 《International Journal of Environmental Science and Technology》2006,3(2):173-176
Prosopis seeds were grown under controlled environment in solution of aluminum and chromium at different concentration alone as well as combined together. The effect of these metals was studied on seed germination, root length, shoot length, seedling length and dry biomass. Aluminum and chromium alone, and combined together showed no effects on germination and dry biomass. Chromium alone was found toxic to root, shoot and seedling length. However, application of different concentrations of aluminum increased the root, shoot and seedling growth. It may be concluded that aluminum is not as toxic as chromium, and their combined treatment showed the intermediate effect by ameliorating the impact of one another. 相似文献
322.
323.
Lithology and conditions of the formation of Paleozoic rocks in northern areas of the Scythian Plate
The Paleozoic sequence recovered during the prospecting for oil and gas in different areas of the Scythian Plate is composed of terrigenous rocks (sandstones, siltstones, silty pelites, mudstones, shales, and phyllites) of different stages of alteration varying from late catagenesis to initial metamorphism. Their investigation allowed us to refine the sedimentation environment during different Carboniferous and Permian epochs at the southern margin of the East European Craton. 相似文献
324.
本文利用中国自动站与CMORPH(Climate Prediction Center Morphing technique for the production of global precipitation estimates)融合的逐时降水量0.1°网格数据集资料挑选出一次典型的梅雨锋暴雨个例,运用WRF中小尺度模式进行模拟,对模拟得到的高分辨率结果进行Barnes滤波,最后将滤波结果代入动能和位能方程中,目的是定量地分析各个尺度能量的变化以及它们之间的相互作用对暴雨强度的影响。研究发现:模式模拟的降水过程和强度与实况较为吻合,推导的能量方程适用于这次暴雨过程。三种尺度能量之间的相互作用包含了各种跨尺度能量的相互作用。在整个暴雨过程中,跨尺度之间的斜压能量转换包括位能向动能的能量转换和动能向位能的能量转换。同尺度之间的斜压能量转换总是单向的,且量值较大,动能的强度主要靠位能向动能的能量转换来维持。斜压能量转换的多少影响着暴雨的强弱。大尺度斜压能量转换在中高层比较强,中尺度斜压能量转换在低层较强,尤以β中小尺度系统变化最为显著,β中小尺度系统扰动是影响暴雨强度的关键系统。风切变的大小影响各尺度动能之间的能量转换。温度或位温梯度的大小影响各尺度位能之间的能量转换。位能与动能之间的能量转换主要与各尺度垂直速度和温度的垂直分布有关,暖空气上升冷空气下沉是各个尺度位能向动能转换的主要过程。 相似文献
325.
In our preceding paper we found solutions for the equations of the bimetric scalar—tensor theory of gravitation for neutron
stars, in which the scalar field is constant while the metric tensor satisfies the equations of the general theory of relativity.
In the present paper we find analogous solutions for different versions of the equation of state of the matter of a neutron
star.
Translated from Astrofizika, Vol. 41, No. 2, pp. 297–301. April-June, 1998. 相似文献
326.
Spatial,spectral, and polarization properties of radio emission of the 3 February, 1983 proton flare
L. M. Bakunin V. G. Ledenev V. P. Nefedyev N. N. Potapov G. Ya. Smolkov A. M. Uralov G. P. Chernov V. V. Fomichev V. P. Melnikov T. S. Podstrigach O. V. Epifanova A. V. Khokhlov Sh. Enome 《Solar physics》1991,135(1):107-129
A complex analysis in different radio ranges of the evolutionary features of the 3 February, 1983 flare (0543-0619-0812 UT) has shown that the flare is a prolonged ( 15 hr) process of energy release and particle acceleration that gradually extends to still greater zones of the active region (AR) magnetosphere in both area and altitude. Observations from the Siberian Solar Radio Telescope obtained at = 5.2 cm indicate that the flare was preceded by quasi-periodical brightness enhancements with a period of 6–7 min of two sources of size 20 and with a brightness temperature of 107 K.During the flare maximum phase, a type II burst with harmonic structure and the subsequent type FC II continuum with fine structure were both observed in the meter band. It has been found that zebra-structure appearances correlate with the H-flare kernel brightenings at loop tops.The observed characteristics of the type II burst and of the type FC II continuum treated in this paper are interpreted in terms of the complex flare flow structure, involving forward and backward shock waves. 相似文献
327.
N. Batmunkh T. N. Sannikova K. V. Kholshevnikov V. Sh. Shaidulin 《Astronomy Reports》2016,60(3):366-373
A precise estimate of the variation of the position of a celestial body in the case of small variations of the elements of its orbit is obtained using an Euclidean (mean-square) norm for the deviation in the position. A relatively simple expression for the mean-square deviation of the radius vector dr in terms of the deviations of the elements is derived. These are taken to be first-order small quantitites, with second-order quantities neglected. This relation is applied to estimate the norm ||dr|| in two problems. In the first one, small and constant differences between six orbital elements (including the mean anomaly) are considered for two orbits. In the second one, a zero-mass point moves under the gravitation of a central body and a small perturbing acceleration F. The vector F is taken to be constant in a co-moving coordinate system with axes directed along the radius vector, the transversal, and the binormal vector. In this latter problem, dr is the difference between the position vectors in the osculating and mean orbit. The norm ||dr||2 is the weighted sum of the squares of the components of F, neglecting higher-order small quantities. The coefficients of the quadratic form depend only on the semi-major axis and the eccentricity of the mean orbit. The results are applied to the motion of a small asteroid under the action of a low-thrust engine imparting a small force. 相似文献
328.
To identify the faults controlling the intensity of recent tectonic processes in the region and to study their geometry and dynamics, one of the variants of the statistical method was used-trend analysis. The map of recent vertical crustal movements in the Carpatho-Balkan region (1:2.000.000) published in Budapest in 1979 was used as initial data for establishing these faults. 相似文献
329.
The Uzbekistan Loess,genesis and distribution 总被引:1,自引:0,他引:1
The distribution and genesis of Uzbekistan loess rocks, their composition, properties and conditions are naturally changing from mountains to the piedmont plains. For the piedmont plains and intermontane depressions the occurrence of alluvial and deluvial loess types is typical, and in the high mountains eluvial, deluvial, eluvial-deluvial and fluvioglacial ones. This can be explained by the difference of tectonic activity as well as by climatic humidity. The study and analyss of the accumulated data of loess of various genetic type, composition and properties show that the initial material of loess formation comes from the mountainous and alpine areas. The primariy sources of the parent rocks are ancient sediments above the limit of loess occurrence. As a result of intensive developments and irrigation in the territory of the republic, loess areas are decreasing, losing their properties, while they are transforming into the loess-like rocks. It was also determined that their structural and textural properties such as porosity, density, salt composition and filtration coefficient are changing simultaneously. The same changes are also noted in the mineralogical and granulometric composition. 相似文献
330.