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41.
采用低温微波法(60、120、180 W)和电加热法对载甲苯松木活性炭进行再生。比较了这两种再生方法下活性炭的再生效率、升温速率、能耗,并分析了再生前后活性炭的物理化学性能。结果表明:经过5次吸附—微波辐射再生之后,活性炭吸附量基本保持原有吸附量的45%。随着微波功率从60 W 升高到120 W,再生时间从60 min降低到22 min,再生效率从1.7%/min增加到4.5%/min。而传统电加热再生法再生时间为180 min, 是微波法的3~6倍; 功率为60 W的微波加热法的升温速率为178 ℃/min,而电加热法升温速率只有9 ℃/min; 从能耗角度看,微波再生法的能耗为29.7 kJ/g,而电加热法的能耗则为74.3 kJ/g; 并且经检测微波法再生后活性炭的孔隙结构和官能团未发生改变。 相似文献
42.
Abdel‐Zaher Abdel‐Aziz Elassar 《Heteroatom Chemistry》2004,15(4):293-299
1,4‐Phenylenediamine was condensed with acetylacetone to give 4,4′‐[1,4‐phenylenedi‐(nitrilo)]‐dipenten‐2‐ol 1 . Compound 1 reacted with different organic reagent to give bisazine derivatives. © 2004 Wiley Periodicals, Inc. Heteroatom Chem 15:293–299, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/hc.20017 相似文献
43.
We prove global existence and scattering for small localized solutions of the Cauchy problem for the Zakharov system in 3 space dimensions. The wave component is shown to decay pointwise at the optimal rate of t ?1, whereas the Schrödinger component decays almost at a rate of t ?7/6. 相似文献
44.
The synthesis and characterization of new transition metal complexes of Mn(II), Co(II), Ni(II), Cu(II) and Zn(II) with 3‐(2‐hydroxynaph‐1‐ylazo)‐1,2,4‐triazole ( HL1 ) and 3‐(2‐hydroxy‐3‐carboxynaph‐1‐ylazo)‐1,2,4‐triazole ( HL2 ) have been carried out. Their structures were confirmed by elemental analyses, thermal analyses, spectral and magnetic data. The IR and 1H NMR spectra indicated that HL1 and HL2 coordinated to the metal ions as bidentate monobasic ligands via the hydroxyl O and azo N atoms. The UV‐Vis, ESR spectra and magnetic moment data revealed the formation of octahedral complexes [Mn L1 (AcO)(H2O)3] ( 1 ), [Co L1 (AcO)(H2O)3]·H2O ( 2 ), [Mn L2 (AcO)(H2O)3] ( 6 ) and [Co L2 (AcO)(H2O)3] ( 7 ), [Ni L1 (AcO)(H2O)] ( 3 ), [Zn L1 (AcO)(H2O)]·H2O ( 5 ), [Ni L2 (AcO)(H2O)] ( 8 ), [Zn L2 (AcO)(H2O)]·10H2O ( 10 ) have tetrahedral geometry, whereas [Cu L1 (AcO)(H2O)2] ( 4 ) and [Cu L2 (AcO)(H2O)2]·5H2O ( 9 ) have square pyramidal geometry.. The mass spectra of the complexes under EI‐con‐ ditions showed the highest peaks corresponding to their molecular weights, based on the atomic weights of 55Mn, 59Co, 58Ni, 63Cu and 64Zn isotopes; besides, other peaks containing other isotopes distribution of the metal. Kinetic and thermodynamic parameters of the thermal decomposition stages were computed from the thermal data using Coats‐Redfern method. HL2 and complexes 6 – 10 were found to have moderate antimicrobial activities against Staphylococcus aureus (gram positive), Escherichia coli (gram negative) and Salmonella sp bacteria, and antifungal activity against Fusarium oxysporum, Aspergillus niger and Candida albicans. Also, in most cases, metallation increased the activity compared with the free ligand. 相似文献
45.
A series of potentially bidentate benzimidazolyl ligands of the type (Bim)CH2D (where Bim = benzimidazolyl and D = NMe2L1, NEt2L2, NPri2L3, OMe L4 and SMe L5) has been reacted with Ti(NMe2)4 to give five- and six-coordinate Ti(IV) complexes of the type [(Bim)CH2D]Ti(NMe2)3 and [(Bim)CH2D]2Ti(NMe2)2, respectively. The X-ray structures of [(Bim)CH2OMe]Ti(NMe2)3, [(Bim)CH2NMe2]2Ti(NMe2)2 and [(Bim)CH2OMe)]2Ti(NMe2)2 are reported along with an evaluation of their behavior in ethylene polymerization. 相似文献
46.
New highly constrained chiral C1-1,1′-bisisoquinoline ligands have been synthesized. X-ray crystallographic analysis of these ligands showed peculiar structural differences between the parent 1′,2′,3′,4′-tetrahydro-1,1′-bisisoquinoline and its alkyl, acyl and sulfonyl derivatives. The consequences of their geometrical conformations on enantioinduction were examined by employing the enantioselective addition of diethylzinc to aldehydes. Such conformations greatly affected the catalytic efficiency of these ligands. 相似文献
47.
Harynuk J Vlaeminck B Zaher P Marriott PJ 《Analytical and bioanalytical chemistry》2006,386(3):602-613
Comprehensive multidimensional gas chromatography (GC×GC) is a powerful separation technique. One of the features of this
technique is that it offers separations with more apparent structure than that offered by conventional one-dimensional GC
(1-D GC). While some previous studies have alluded to this structure, and used structured retention patterns for some simple
classifications, the topic of structured retention in GC×GC has not been studied in any great detail. Using the separation
of fatty acid methyl esters (FAME) on both nonpolar/polar and polar/nonpolar column sets, the interaction between the separation
dimensions and the sample dimensions is explored here. The GC×GC separation of a series of compounds is presented as a projection
of the sample from sample space, a p-dimensional space with dimensions defined by the dimensionality of the sample, into separation space: for GC×GC, a two-dimensional plane passing through the sample space in an orientation defined by the separation conditions.
Using this conceptual model and some a priori knowledge of the sample, it is shown how the image of the sample in the separation
space can be used to construct an image of the sample in alternate dimensions, such as second dimension retention factor (2k) vs. chain length in the case of FAME. These projections into alternate dimensions should facilitate the interpretation
of the complex patterns found within the GC×GC chromatogram for the identification and classification of compounds. 相似文献
48.
49.
The action of phenylmagnesium bromide on 6-p-chlorostyryl-3-thioxo-1,2,4-triazin-5-one ( 1 ) was studied whereby a mixture of seven products was obtained. These were separated and characterised, and a reasonable mechanism for their formation is presented and discussed. 相似文献
50.
We consider the cubic nonlinear Schrödinger equation with harmonic trapping on ?D (1 ≤ D ≤ 5). In the case when all directions but one are trapped (aka “cigar‐shaped trap”), we prove modified scattering and construct modified wave operators for small initial and final data, respectively. The asymptotic behavior turns out to be a rather vigorous departure from linear scattering and is dictated by the resonant system of the NLS equation with full trapping on ?D?1. In the physical dimension D = 3, this system turns out to be exactly the (CR) equation derived by Faou, Germain, and the first author as the large box limit of the resonant NLS equation in the homogeneous (zero potential) setting. The special dynamics of the latter equation, combined with the above modified scattering results, allow us to justify and extend some physical approximations in the theory of Bose‐Einstein condensates in cigar‐shaped traps.© 2016 Wiley Periodicals, Inc. 相似文献