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101.
102.
M. Sandoli A. Boiano L. Campajola A. De Rosa A. D'Onofrio G. Inglima M. La Commara A. Ordine D. Pierroutsakou V. Roca M. Romano M. Romoli M. Trotta F. Rizzo F. Amorini S. Tudisco 《The European Physical Journal A - Hadrons and Nuclei》1999,6(3):275-288
We report on the results obtained from the study of the 32S +74Ge deep inelastic reaction at incident energy E= 320 MeV. High-energy γ-rays were detected in an array of 6 seven-pack BaF2 clusters. Coincidence with complex fragments detected in 12 three-stage telescopes ensured the selection of peripheral reaction
events. In order to investigate the pre-equilibrium dipole strength excitation two independent analyses were performed. In
the first analysis the energy spectra of the γ-rays were evaluated in the statistical model framework while in the second
one the γ-ray fragment angular correlation with respect to the nuclear spin vector of the composite system was studied. Both
methods indicate the excitation of dipole strength in the highly deformed dinucleus and provide dipole resonance parameter
sets that are in good agreement with each other.
Received: 24 March 1999 / Revised version: 17 May 1999 相似文献
103.
104.
伴随有水蒸气凝结的烟气对流换热的实验研究 总被引:13,自引:0,他引:13
本文通过实验研究了冷凝式燃气热水器中烟气伴随有水蒸气凝结的受迫对流换热过程。着重介绍实验系统、测试方法和对塔板式换热器和肋片板式换热器的实验研究结果。实验表明,有水蒸气凝结时的烟气对流换热系数远大于无凝结时的换热系数,可提高数倍。在冷凝式换热器中,塔板式换热器的换热系数大于肋片板式换热器。 相似文献
105.
艾明 《中国无机分析化学》2013,3(1):74-76
研究了采用氢化物发生-原子吸收光谱法测定食品中痕量汞的方法,通过采用氢化物发生器,选择合适浓度的载流和硼氢化钾,获得了较为满意的分析结果。在测定汞含量5~20μg/kg的食品标准样品时,测试结果相对标准偏差RSD为2.2%~3.7%,回收率为84.9%~97.5%,检出限为0.2μg/L,完全满足食品行业汞元素痕量检测要求,操作简便、快速。 相似文献
106.
分子电子学已成为21世纪研究的热点. 通过将具有特定功能的分子连接在纳米尺度金属电极之间从而构筑包括分子导线、开关、整流器在内的各种分子尺度电子器件, 这引起了科学家们广泛的研究兴趣. 在分子电子学研究中, 构筑金属/分子/金属(MMM)分子结是研究分子器件中电子传输性质的关键. 尽管已经取得了很大的进展, 目前在纳米尺度下构筑稳定可靠的MMM分子结并测试单个分子的电学性质仍然面临很多挑战. 本文着重对单分子电学性质的测试技术和相关理论研究的最新进展以及存在的挑战做了概述. 相似文献
107.
CHEN Xing YIN Lipu ZHOU Hongyu LIU Junyou LI Xiaohui AI Xianbin HUANG Kai 《高等学校化学研究》2018,34(6):1020-1027
Wastewater produced from the soil washing process contains heavy metals, which limits its reuse for washing. So it is necessary to develop an efficient and economical way to recycle it, and this study presented a biosorption method to realize this goal. A typical soil sample contaminated by lead was taken from the real field near a lead smelting factory, used for the toxic metals extraction with dilute citric acid. A leach liquor was obtained with lead ions at the level of 12.35 mg/L, Cd 1.2 mg/L, Cu 1.5 mg/L, Zn 2.6 mg/L, as well as the coexisting anions, such as sulphate, silicate, chloride at the concentration of several hundred miligram per liter. The garlic peel was modified by a simple chemical saponification process and used as the biosorbent for toxic metal removal. Firstly, the adsorption behavior of lead ions on the saponified garlic peel was systematically investigated using the synthetic solutions, and then the adsorption mechanisms were explored by detailed experiments combining with the thermodynamic calculation reuslts of the aqueous system of Pb(Ⅱ)-citrate-H2O. It was found that in artificial solution containing 0.01 mol/L citrate, the maximum adsorption capacity of 261.0 mg/g was reached at pH near 3.0, and also at this very pH value the Pb2+ and Pb(H2Cit)+ were the dominant lead species, which are favorable for adsorption due to its easier approaching to the -COO- ligands in the saponified garlic peel partilces via charge attraction, and the appearance of Pb(HCit)0 and Pb(Cit)- at pH above 3.0 inhibits the adsorption. Secondly, the real leach liquor was used for adsorption tests, and twice adsorption under the optimal conditons would decrease the residual concentrations of Pb, Cd, Cu and Zn to zero. After elution by using 0.1 mol/L nitric acid, the adsorbed metals can be recovered and garlic peel can be reused for at least 10 cycles effectively. This study presents a prospective biosorption method for economical and efficient removal of the lead ions from soil washing wastewater with citric acid as the leaching reagent. 相似文献
108.
The transport of Brownian particles in the infinite channel within an external force along the axis of the channel has been studied. In this paper, we study the transport of Brownian particle in the infinite channel within an external force along the axis of the channel and an external force in the transversal direction. In this more sophisticated situation, some property is similar to the simple situation, but some interesting property also appears. 相似文献
109.
Evolutionary game dynamics is one of the most fruitful frameworks for studying evolution in different disciplines, from Biology to Economics. Within this context, the approach of choice for many researchers is the so-called replicator equation, that describes mathematically the idea that those individuals performing better have more offspring and thus their frequency in the population grows. While very many interesting results have been obtained with this equation in the three decades elapsed since it was first proposed, it is important to realize the limits of its applicability. One particularly relevant issue in this respect is that of non-mean-field effects, that may arise from temporal fluctuations or from spatial correlations, both neglected in the replicator equation. This review discusses these temporal and spatial effects focusing on the non-trivial modifications they induce when compared to the outcome of replicator dynamics. Alongside this question, the hypothesis of linearity and its relation to the choice of the rule for strategy update is also analyzed. The discussion is presented in terms of the emergence of cooperation, as one of the current key problems in Biology and in other disciplines. 相似文献
110.