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741.
Bearbeitet von F. Keschmann 《Baurechtliche Bl?tter: bbl》2007,10(2):68-69
Wenn die Nachprüfungsbeh?rde in die Sache eingegangen ist, hat sie (lediglich) zu prüfen, ob die Rechtswidrigkeit auf den
Ausgang des Vergabeverfahrens einen wesentlichen Einfluss hatte oder hat. 相似文献
742.
743.
This study investigated the effect of dosage of Ag on the characteristics of TiO2, quantum yield, and temporal decomposition behavior of o‐cresol in an annular reactor under ultraviolet (UV) and visible light irradiation. In order to extend light absorption and minimize the rapid recombination during photoreaction, the Ag deposited on TiO2 photocatalysts was prepared by a photodeposition process. The results of diffuse reflectance spectra (DRS) indicated that Ag deposited on TiO2 promoted the optical absorption in the visible region and made it possible for it to be excited by visible light. The degradation rate of o‐cresol with 0.50 wt % Ag/TiO2 under visible light irradiation was 2.0 times that with pure TiO2. 相似文献
744.
本文研究番红花红O(safranin eo)-肝素钠(heparin)体系的共振瑞利散射(RRS)光谱及紫外光谱,考察了体系的光谱特征,适宜的反应条件和主要影响因素。结果发现:在近中性(PH=6.0)的B-R缓冲溶液中,肝素钠与甲基红染料形成离子缔合物后,且在一定范围内,RRS强度与肝素钠浓度成正比。检出线为6.5 ng ml?1.并且研究了共存物质的影响,表明此方法选择性好,用于肝素钠注射液效价的测定,结果满意。 相似文献
745.
746.
Yoshimi Sato Nilo Bazzoli Elizete Rizzo Maria Beatriz Boschi Mario O. T. Miranda 《河流研究与利用》2005,21(8):939-950
The curimatã‐pacu Prochilodus argenteus is an important characiform from the São Francisco River basin that performs long‐distance migrations for spawning upstream during the rainy season, when the temperature and photoperiod are elevated. Despite the interruption of the migratory routes by the Três Marias Dam and accentuated decline in fishing, the curimatã‐pacu still sustains the fisheries at the Três Marias region in recent decades. The objective of this study was to evaluate the reproductive activity of P. argenteus in two sections of the São Francisco River, downstream from the Três Marias Dam, during the rainy season. In the first 34 km of the river, immediately below the dam, most of the females were in gonadal resting. At 34–54 km downstream from the dam, following the confluence with a medium‐sized tributary, the Abaeté River, there was a high frequency of males and females in reproductive activity. Follicular atresia was more frequent in the upper section of the river while postovulatory follicles occurred predominantly in the lower section. Fulton's condition factor and gonadosomatic index indicated that the females were in a better physiological and reproductive condition below the confluence with the Abaeté River. In contrast to the females, the males were less affected by damming, and testicular maturation was largely achieved in two river sections. Thus, although the section of the São Francisco River immediately below the Três Marias Dam was found to be unfavourable for the reproduction of the migratory fishes due principally to the hypolimnetic water from the reservoir, reproductive success of P. argenteus was achieved below the Abaeté River. In this section, the species encountered appropriate conditions for maturation and spawning, i.e. warm temperatures above 24°C, high water flow and dissolved oxygen, and low water transparency. These results indicate the importance of a non‐regulated tributary to minimize the ecological impact of a dam on the downstream native fish communities. Copyright © 2005 John Wiley & Sons, Ltd. 相似文献
747.
Hydrogen formation by the photodecomposition of water has been successfully achieved in a water in oil emulsion (w/o emulsion)
system containing Pt/TiO2. The hydrogen formation rate was affected by the amount of water added to the emulsion. It was concluded that water in the
w/o emulsion containing Pt/TiO2 was more active than free water for the photodecomposition to form hydrogen.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
748.
测氡法在应用于油气勘探时,取样装置及测试条件均须改进。改进后的装置主要增加了一个密封胶环,这不仅起到了封闭作用,而且还对保护管起到了定位作用;测试条件的改进主要是延长取样时间1分钟,将原孔深35cm增加到155cm。改进后的装置在文31油藏的测试中,记数率平均达80脉冲/min以上,平面图上环状异常形态清楚,且测出了负异常。 相似文献
749.
提出一种新型的光控光开关,利用倍频Nd:YAG脉冲激光作为控制光束泵浦C60溶液,形成瞬态透镜效应,使同时反方向通过样品的633nm宽光束的氦氖激光实现光开关。这种光开关响应快,开关对比度大,可完全避免控制光束的干扰。 相似文献
750.
提出了一个描述K3C60的amiltonian量,利用Green函数方法求出了计算其电导率的公式,并进行了数值计算,与实验结果比较相符。 相似文献