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121.
The use of biomass and waste for decentralised combined heat and power production (CHP) requires highly efficient gasification processes. In the Technische Universität München (TUM), an innovative gasification technology has been developed. This allothermal gasifier is producing a hydrogen- rich, high-calorific gas, that can be further used in a microturbine or a fuel cell producing energy. For the operation of such a system, the online analysis of the composition of the product gas is of high importance, since the efficient working of the machines is linked with the gas quality. For this purpose an optical measurement system based on laser spectroscopy has been applied. This system can measure not only the basic components of the product gas (H2, CH4, CO, CO2, H2O), but it also gives information concerning the content of high hydrocarbons, the so-called tars, in the product gas. 相似文献
122.
We present the second part of the investigation of the high sensitivity absorption spectrum of nitrous oxide by CW-Cavity Ring Down Spectroscopy near 1.5 μm. In a first paper [A.W. Liu, S. Kassi, P. Malara, D. Romanini, V.I. Perevalov, S.A. Tashkun, S.M. Hu, A. Campargue, J. Mol. Spectrosc. 244 (2007) 33-47] devoted to the 6000-6833 cm−1 region, more than 6000 line positions of five isotopologues (14N216O, 15N14N16O, 14N15N16O, 14N217O, and 14N218O), were rovibrationally assigned to a total of 68 bands. The achieved noise equivalent absorption (αmin ∼ 2 × 10−10 cm−1) allowed for the detection of lines with intensity weaker than 2 × 10−29 cm/molecule. In this contribution, the investigated region was extended down to 5905 cm−1 and additional recordings allowed accessing small spectral sections uncovered in our preceding recordings. A deeper analysis based on the predictions of the effective Hamiltonian model has allowed assigning a total of 3149 transitions and lowering the percentage of lines left unassigned from 51% to 28%. It led to the analysis of 35, 6, 7, and 6 bands for the 14N216O, 15N14N16O, 14N15N16O, and 14N218O isotopologues, respectively. Forty-two of these 54 bands are newly observed, while the rotational analysis of the twelve others is significantly extended and improved. Most of the bands were found unperturbed and their line positions could be reproduced within the experimental uncertainty (about 1 × 10−3 cm−1). The corresponding spectroscopic parameters are reported. Local rovibrational perturbations induced by either intrapolyad or interpolyad couplings were found to affect five hot bands of 14N216O. Their detailed analysis is presented. 相似文献
123.
Rebecca A.H. Butler Paul Helminger Ewa Bialkowska-Jaworska 《Journal of Molecular Spectroscopy》2007,244(2):113-116
The pure rotational spectrum of chlorine nitrate in its v6 = 1 excited vibrational state has been studied. A total of 2901 lines, with Ka extending to 33 in the 35Cl isotopologue and 30 in the 37Cl isotopologue, respectively, have been recorded and assigned. This analysis, along with our recently reported study of the ν5/ν6ν9 dyad and the improved energy levels of ν9 reported in this paper, should make possible accurate simulation of the corresponding ν6 band and its complex hot band structure near 435 cm−1. 相似文献
124.
Single crystal dixanthinium tetrachlorozincate has been grown from dilute chloridric acid. Polarized Raman spectrum of the single crystalline sample, FT-Raman and FT-IR spectra of the polycrystalline samples have been examined and the bands assigned to the appropriate modes predicted by a factor group analysis for the space group Pmn21. The crystal structure has been confirmed by powder XRD measurements. 相似文献
125.
In this paper, the interactions of meso-Tetrakis (4-sulfonatophenyl) porphyrin (TPPS 4 ) and six cyclodextrins have been studied, respectively, by fluorescence spectroscopy, polarography and thin-layer chromatography. The inclusion constants of different methods are determined and the comparison of inclusion capacity of various cyclodextrins indicates that for the ionic cyclodextrins the charge interaction plays an important role in the inclusion procedure. The thermodynamic parameters of interaction imply that the inclusion process shows the enthalpy-entropy compensation effect. Cyclodextrin, being regarded as an artificial analogue of proteinoid of heme, provides a protective sheath for porphyrin. However, the TPPS 4 , encapsulated within this saccharid-coated barrier, its solubility is enhanced prominently, which exhibits that this interaction may modify the biological properties of TPPS 4 that owned the similar properties as hematoporphyrin. 相似文献
126.
化探样品中金含量测定的探讨 总被引:1,自引:0,他引:1
讨论了化探样品中金测定过程中的分解方法、金的富集、酸度及流速、泡塑清洗及控制等条件,严格控制各个分析环节,通过对标准样品进行分析,相对标准偏差为0.75%—3.64%,回收率为95.0%—105.0%,方法适合批量样品生产,能达到化探样品中金含量的分析要求。 相似文献
127.
The UV-Visible absorption Spectra for the complexes cis and trans BrMn(CO)2dppm(P(OPh)3) dppm = Ph2PCH2PPh2 in several solvents are reported and an assignment of their bands is proposed. The cis isomer present one characteristics band in the visible region while that the trans isomer exhibits two well defined absorption bands. This spectral behavior is in agreement with early thermodynamic considerations. 相似文献
128.
Ph. Pruzan J. C. Chervin M. M. Thiéry J. P. Itié J. M. Besson J. P. Forgerit 《高压研究》2013,33(1-6):215-217
Abstract After a pressure cycle to 30 GPa, benzene transforms to a white solid which can be recovered at ambient. Results obtained from infrared spectroscopy and other physico-chemical methods show that the recovered solid is a highly cross-linked polymer. The molecular structure of benzene is very likely completely altered by the transformation. 相似文献
129.
Despite their simplicity, diatomic molecules of first row elements can exhibit very complex phase diagrams. Determination of the phase diagrams can be further complicated by the existence of hysteretic molecular phases that can be observed over large regions of coexistence. Here we present evidence for a previously unreported molecular phase of nitrogen existing at room temperature at least over the range of 33-74 GPa. Our measurements show that sample history may have a significant impact on the thermodynamic states accessed by the molecular nitrogen solid and, by extension, also on the established phase diagram. 相似文献
130.
Complexes of uranium in its IV oxidation state, using cysteine, glycine, serine and aspartic acid as ligands, have been synthesized. Semi-microanalysis of the complexes indicate 1:1 metal to ligand ratio for all the synthesized complexes. Infrared spectra of solid complexes have been employed to establish the groups, coordinated to the metal ion. Effective magnetic moment of the complexes were also estimated. 相似文献