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51.
镀铜铁屑-H_2O_2催化氧化降解含酚废水 总被引:2,自引:0,他引:2
采用镀铜铁屑代替传统Fenton体系中的FeSO4作为催化剂,通过改变H2O2与镀铜铁屑的投加量、溶液的pH值、反应温度、反应时间等条件,研究了该体系对处理苯酚废水的影响。结果表明,常温下处理实际含酚印染废水,在pH值为4~6,30%H2O2 12mL/L,镀铜铁屑5g/L,反应时间为45min时,COD去除率可达96%,其CODCr从5827mg/L降至419mg/L,色度从2000降至30,符合国家三级排放标准。 相似文献
52.
Summary Inverse gas chromatography is shown to be suitable for the study of the oxidation of vegetable oils. With air as carrier gas
characteristic plots of retention index versus time are obtained for hydroxylic test solutes that are consistent with the
oxidation behaviour of vegetable oils. Shifts of retention are found to be accompanied by changes of column efficiency due
to the oxidative crosslinking of polyunsaturated vegetable oils. The technique also leads to useful information concerning
the oxidation of antioxidant inhibited systems.
Presented at the 15th International Symposium on Chromatography, Nürnberg, October 1984 相似文献
53.
Summary To match the need of high efficiency capillary column (plate number N2, Plate height H2 and carrier gas linear velocity U2), a new high efficiency packed column (N1, H1 and U1) at high carrier gas velocity with small capacity factor has been developed in the light of theoretical discussion of factors
effecting the column efficiency utilization ratio. 相似文献
54.
TiO2光催化反应及其在环境保护中的应用 总被引:8,自引:0,他引:8
本文简要介绍了TiO2光催化剂的作用机理,讨论了影响TiO2光催化效率的因素及解决途径,综述了光催化在环境保护中的最新应用。 相似文献
55.
56.
Synthesis and fluorescent properties of some new unsymmetricbis-benzothiazolyl furans and thiophenes
L. Racane V. Tralić-Kulenović G. Karminski-Zamola L. Fišer-Jakić 《Monatshefte für Chemie / Chemical Monthly》1995,126(12):1375-1381
Summary Some newmono- andbis-benzothiazolyl compounds with furan or thiophene nuclei were synthesized by multistep reactions from the corresponding furan and thiophene aldehydes. The data obtained from emission spectra show a large influence of the benzothiazole rings on the relative quantum efficiency of the compounds under investigation.
Synthese und Fluoreszenzeigenschaften von neuen unsymmetrischenbis-Benzothiazolylfuranen und thiophenen
Zusammenfassung Einige neuebis-Benzothiazolylverbindungen mit einem Furan- bzw. Thiophenenring wurden in einer mehrstufigen Reaktion dargestellt. Die Fluoreszenzdaten der untersuchten Verbindungen zeigen einen großen Einfluß der Benzothiazolringe auf die relative Fluoreszenzquantenausbeute.相似文献
57.
Relative mass transport efficiencies of near infrared (λ = 795 nm) femtosecond laser generated brass aerosols in helium were measured by ICP-MS applying different ablation cells with short and long washout times. It was found that the transport efficiencies are independent of the cell used within the mutual experimental uncertainties. This finding was confirmed by additional measurements providing the absolute particle mass transport efficiencies of femtosecond laser ablation in He. Here, the transport efficiencies were determined by weighing the samples before and after ablation with a micro-balance, collecting the particles by low-pressure impaction, and evaluating the impacted masses quantitatively by total reflection X-ray fluorescence. Within the experimental uncertainties (± 9–19%) the same absolute transport efficiency (about 77%) was found for all cells applied. This efficiency value can be regarded as a lower limit of the absolute mass transport efficiency since mass losses in the impactor are difficult to quantify. 相似文献
58.
Four para-dialkylaminophenyl (PDAAP1-PDAAP4) bearing carboxyl groups were studied for application to the dye-sensitized solar cells (DSC). It was found the short spacer CH2 between carboxyl and dialkylaminophenyl chromophore in PDAAP3 and PDAAP4 led to highly efficient monochromatic incident photon-to-current conversion efficiencies (IPCE), however the long alkyl group C4H9 attached on aniline moieties in PDAAP2 and PDAAP4 favored improvement of open-circuit photovoltage. Thus, the solar cell sensitized by PDAAP4, having both short carboxyl groups CH2COOH and long alkyl groups C4H9, exhibited the IPCE maximum of 73% at 670 nm and overall energy conversion efficiency η of 3.06%, representing the highest IPCE and η values so far in dialkylaminophenyl-based organic dye-sensitized semiconductor solar cells. Taking advantage of the highly efficient sensitizing ability of PDAAP4 in far-red region, the data of IPCE above 630 nm of the solar cells were improved greatly by cosensitization with both N3 and PDAAP4. The influences of the TiO2 film thickness and the concentration of 4-tert-butylpyridine (TBP) in electrolyte were also investigated. 相似文献
59.
南药巴戟天中十二种无机元素与药效关系的进一步研究 总被引:4,自引:0,他引:4
在初步研究的基础上,进一步研究了不同产地巴戟天的无机元素含量差异,通过对比各元素含量、相关系数及TE图谱,说明地道药材与非地道药材的巴戟天,其特征元素的含量存在非常明显的差异,要使大面积扩种的药材提高药效,建议根据当地土壤含Mn、Fe、Cr、Co、Ni的含量,以旋微量元素肥料的方法来补充这些元素在土壤中的不足。但在微量元素肥料配方中,应注意巴戟天吸收土壤中的元素时的协同作用和拮抗作用。 相似文献
60.
Summary A program is described which calculates the number of effective plates and the coating efficiency over the entire range of a test chromatogram. The peak widths at half height are derived by assuming a Gaussian peak shape. The interpolated peak width at k=4 is used for computing a standardized number of effective plates. Plate height, column permeability, overall performance and a novel parameter called sampling efficiency are calculated from 5 other figures — i. e. carrier gas code, pressure drop, column length, column temperature and particle size.Dedicated to Dr. Leslie S. Ettre for his 60th birthday. 相似文献