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141.
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通过配置一定浓度的含二氯甲烷的有机废气,考察了UV、H2O2和Fenton等单一及组合氧化工艺氧化降解二氯甲烷的技术可行性.研究表明,UV/H2O2联合法对二氯甲炕的降解效果较好,其最优反应条件为30%H202用量1.5mL,初始pH=3~7,吸收液循环再生流量200mL·min^-1,紫外灯功率8w.此外,考察了UV/H2O2体系氧化降解二氯甲烷的动力学特性,结果表明,在紫外光强度稳定、液相反应物均匀分布、且H2O2用量过量的条件下,该氧化降解过程遵循准一级反应动力学方程. 相似文献
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144.
Sun Ziyang Wang Shunuan Zhang Jingshang Zhuo Yizhong 《Zeitschrift für Physik A Hadrons and Nuclei》1982,305(1):61-68
An exact closed form solution to the time-integrated master equation of the exciton model is applied to the calculation of the angular distribution for both the preequilibrium and equilibrium decays of the neutron-induced reaction. The distribution probability of two-nucleon collision fromΩ toΩ′ based on the Fermi gas model and the influence of the Fermi motion and the Pauli principle on the shape of the angular distribution are studied in detail. We have concluded that the influence of these effects on the shape of the angular distribution is rather significant for reactions in the energy range of several tens of MeV. As an example to compare with the experiments we have calculated the neutron-induced reaction93Nb(n,n′) atE n =15 MeV. It seems that the most significant improvement of the present approach is the rise of the backward direction of the double differential cross section for the higher energy emitted neutrons. 相似文献
145.
本文以技术转让中的价格谈判为背景,建立了一类谈判问题的灰色规划模型,给出了该模型的求解步骤的方法,并通过实例说明了有关模型的应用。 相似文献
146.
Zhang Y Zhang G Clarke PA Huang JT Takahashi E Muirhead D Steenwyk RC Lin Z 《Journal of mass spectrometry : JMS》2011,46(7):705-711
Quantitation of urinary tetranor PGDM or tetranor PGEM (tPGDM and tPGEM) in the past was performed separately using off-line SPE LC-MS/MS methods. The manual SPE procedure is generally time-consuming and cost-ineffective. In addition, simultaneous quantitation of tPGDM and tPGEM is favorable yet very challenging because of the similar chemical structures and identical MRM transitions. This work describes the development and validation of a high-throughput online SPE-LC-MS/MS method, allowing simultaneous and high-throughput measurement of tPGDM and tPGEM in human urine. The reportable range of the assay was 0.2-40 ng/ml for tPGDM and 0.5-100 ng/ml for tPGEM. Intra- and inter-assay precision and accuracy determined using quality control samples were all within acceptable ranges (% CV and % Bias < 15%). Tetranor PGDM was stable under all tested conditions while tPGEM was stable at 4 °C and after three F/T cycles but not stable at room temperature for 24 h (recovery below 80%). The assay was applied to measure urinary tPGDM and tPGEM among healthy volunteers, smokers and COPD patients. Significantly higher urinary levels of both tPGDM and tPGEM were observed in COPD patients than those of non-smoking healthy volunteers. These results demonstrated that the high-throughput online SPE-LC-MS/MS assay provides sensitive, reproducible and accurate measurement of urinary tPGDM and tPGEM as biomarkers for assessing inflammatory diseases such as COPD. 相似文献
147.
采用多重网格法(MG)和对称性理论以及密度泛函理论中著名的Kohn-Sham 方程,开发了一种计算具有一定对称性的原子簇的电子结构的方法,并对H2 分子的基态能进行了实际的计算,并与用其他理论计算得到的结果进行了比较。 相似文献
148.
In the framework of two-center shell model the nearest neighboring level spacing distribution and spectral rigidity of the nucleon in heavy nuclei are calculated when the shape parameters are changed systematically. Two regions of shape parameter in which the chaotic motion of the nucleon occurs are found. It is shown that the chaotic motion appears not only in the heavy nuclei with oblate shapes but also in prolate ones with a considerable neck, which is quite different from the conclusions of Ref. [2]. Bohigas Giannoni Schmit conjecture is corroborated once again by the good quantum-classical correspondence of nucleonic regular (chaotic) motion. In addition, the present work suggests that nuclear dissipation is shape-dependent,strong dissipation is expected for medium or larger separations, and provides nuclear dissipation with a dynamical understanding. 相似文献
149.
Ming Zhang Gaole Dai Caijun Zheng Kai Wang Yizhong Shi Xiaochun Fan Hui Lin Silu Tao Xiaohong Zhang 《中国化学快报》2022,33(2):1110-1115
Thermally activated delayed fluorescent(TADF) materials capable of efficient solution-processed nondoped organic light-emitting diodes(OLEDs) are of important and practical significance for further development of OLEDs. In this work, a new electron-donating segment, 2,7-di(9 H-carbazol-9-yl)-9,9-dimethyl-9,10-dihydroacridine(2 Cz-DMAC), was designed to develop solution-processable non-doped TADF emitters. 2 Cz-DMAC can not only simultaneously increase the solubility of compounds and suppress har... 相似文献