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1.
在常温常压下,由乙二胺(EDA)和乙二醇及其衍生物(EGs)组成的混合体系可捕集SO2并转化为一种SO2储集材料(SO2SM)。EDA+EGs体系呈现了强的捕集性能(0.364~0.662 gSO2·gabsorbent-1)。FTIR,XPS和XRD结果确证了SO2SM为一种烷基亚硫酸盐。以EG-SO2SM为原料制备具有多种形貌的BaSO3或BaSO4,在此过程中,EG-SO2SM不仅提供了原材料,而且可以释放EDA和EG用作表面活性剂,调控晶体的结晶化过程。  相似文献   

2.
在常温常压下,由乙二胺(EDA)和乙二醇及其衍生物(EGs)组成的混合体系可捕集SO2并转化为一种SO2储集材料(SO2SM)。EDA+EGs体系呈现了强的捕集性能(0.364~0.662 gSO2·gabsorbent-1)。FTIR,XPS和XRD结果确证了SO2SM为一种烷基亚硫酸盐。以EG-SO2SM为原料制备具有多种形貌的BaSO3或BaSO4,在此过程中,EG-SO2SM不仅提供了原材料,而且可以释放EDA和EG用作表面活性剂,调控晶体的结晶化过程。  相似文献   

3.
The potential energy surfaces for the nine low-lying electronic states of SO2 have been constructed by using the multi-reference second order perturbation theory (MRPT2) with the basis set cc-pVTZ. The optimized geometries and the adiabatic excitation energies of these states are in good agreement with experiments and previous calculations. The crossings and avoided crossings displayed in the potential energy surfaces are expounded.  相似文献   

4.
采用红外(IR)、拉曼(Raman)、X-射线衍射(XRD)、程序升温还原(TPR)等方法考察了经硫酸根改性后的金红石(SR)与锐钛矿(SA)的混合比例变化时的负载型催化剂,MoO3 / TiO2(SR+SA),的一些物理化学性质(如活性组分MoO3的分散行为、表面酸碱性、氧化还原性)的变化规律。结果表明:对于MoO3 / TiO2(SR+SA)样品,低含量MoO3表面分散时倾向于优先与混合载体中的改性金红石(SR)发生作用;TiO2载体表面SO42-的存在,使得载体表面产生了新的酸性位,导致样品中表面分散的钼物种主要以聚合八面体状态存在。  相似文献   

5.
自从1991年日本科学家Iijim a发现碳纳米管以来,在纳米管制备和理论方面的研究引起了广泛的关注[1]。管状、线状、棒状、带状、针状等一维纳米结构已成为世界各国研究人员关注的焦点[2 ̄6]。究其原因在于其特殊的物理性质,对于纳米领域的基础研究有新的启发作用,这些一维纳米结  相似文献   

6.
Raman and FTIR spectra of guanidinium zinc sulphate [C(NH2)3]2Zn(SO4)2 are recorded and the spectral bands assignment is carried out in terms of the fundamental modes of vibration of the guanidinium cations and sulphate anions. The analysis of the spectrum reveals distorted SO42− tetrahedra with distinct S–O bonds. The distortion of the sulphate tetrahedra is attributed to Zn–O–S–O–Zn bridging in the structure as well as hydrogen bonding. The CN3 group is planar which is expressed in the twofold symmetry along the C–N (1) vector. Spectral studies also reveal the presence of hydrogen bonds in the sample. The vibrational frequencies of [C(NH2)3]2 and HC(NH2)3 are computed using Gaussian 03 with HF/6-31G* as basis set.  相似文献   

7.
用酸中和法制备了活性γ-Al2O3, 并在其表面负载SO3得到固体酸催化剂SO3/γ-Al2O3, 用XRD, TG-DTA, FT-IR,NMR, NH3-TPD等对其进行了结构和酸性研究. 结果表明: 在SO3/γ-Al2O3的制备过程中形成少量的Al2(SO4)3, 同时SO3与γ-Al2O3表面上的羟基反应, 形成强的Brönsted酸位, 根据1H/27Al 双共振(TRAPDOR)MAS NMR与FT-IR实验结果提出了Brönsted酸结构模型. SO3/γ-Al2O3表面存在两种不同强度的酸中心, 其酸强度大于分子筛HZSM-5, 但弱于传统的固体超强酸 /γ-Al2O3.  相似文献   

8.
Spectra of coincidence of SO2 IR absorption with CO2-laser emission at pressure of 50,100 and 450 Torr were recorded by the use of a photoacoustic detection method in the whole range of CO2-laser emission. The spectra show that SO2 absorbs many CO2-laser lines in the range 1084–1071 cm−1 with the strongest absorption at 1082.29cm−1, laser line R(26). The intensities of all absorptions rise with increasing pressure, but some absorptions change their relative intensity with respect to one another. In addition, the fine structure of line spectra, characteristic of lower pressure samples, disappear as pressure is increased.  相似文献   

9.
不使用有机模板剂,采用超声化学法一步水解制得吸附硫酸根的介孔偏钛酸,500℃焙烧得到介孔SO2-4/TiO2固体超强酸.用XRD、TFEM、FTIR、低温氮吸附-脱附等手段对催化剂结构进行了表征.结果表明,硫酸根在焙烧过程中与前驱体介孔偏钛酸孔壁上自由羟基的键合起到了孔结构导向及支撑作用,500℃焙烧后样品具有161 m2·g-1的比表面积及4.1 nm的平均孔径,酸强度H0介于-14.52与-16.02之间,硫含量为2.8%,晶型全部为锐钛矿相,介孔SO2-4/TiO2具有较大比表面、强酸特性和稳定性.催化合成富马酸二甲酯的最佳条件为:n(甲醇):n(富马酸)=6:1,催化剂用量为1.0%(反应物总质量),带水剂苯用量为10 mL,反应时间为3 h,催化剂重复使用7次,酯化率大于90%.  相似文献   

10.
A Raman study of K3H(SO4)2 as a function of temperature reveals that this compound undergoes a phase transition at Tc = 483 K prior to the decomposition at 508 K.  相似文献   

11.
纳米复合固体超强酸SO42-/CoFe2O4的制备和表征   总被引:26,自引:0,他引:26  
采用纳米化学制备技术合成了新型的纳米复合固体超强酸催化剂SO4^2-/CoFe2O4。用XRD、TEM、XPS、红外光谱和比表面测定等技术研究了该催化剂的结构形态,结果表明:所研制的SO4^2-/CoFe2O42催化剂为晶态纳米粒子(〈50nm),比表面积很大(157m^2.g^-1),SO4^2-与氧化物的金属离子呈无机齿螯合状配位化合物的结合形式。以乙酸乙酯合成为模型反应考究了该催化剂的催化活  相似文献   

12.
Traditionally the monitoring of atmospheric pollutants is aimed at managing accidents and short-term actions for the protection of human health on local and regional scales. These monitoring networks required continuous measurements with high time resolution, involving costly equipment, operation and maintenance. More recent simulations with mathematical models and scenario-building on regional, continental and global scales, as well as studies of environmental personal exposure are demanding three main types of monitoring design, where need for special resolution surpasses the one of temporal resolution: remote places, where no electric power nor trained human resources are available; validation of dispersion simulation by mathematical modeling on regional to larger scales; indoor measurements where people are acting under noise restriction such as residences, school and hospitals. To meet these demands environmental passive samplers for atmospheric gaseous pollutants have been developed and applied for different situations and environments of Brazil. Passive samplers were developed based on molecular diffusion of gas through a static layer of air with fixed filters impregnated with a specific solution for SO2, NO2, O3 and H2S and used in the following situations: in remote forest area, urban areas with different characteristics - near the sea, with clean ocean air masses coming in and in areas under direct industrial influence. The passive samplers showed good performance when exposed to different types of areas and during different periods: accuracy of measurements, based on standard deviation, were within the recommended limit by the European Union of ± 25% for this type of device and precision below the maximum of 20% cited in the literature, with variation of 2.0 to 16% in the case of these work. The passive devices were able of measuring concentrations very low as those found in the Amazon region (0.58 ± 0.05 µg m− 3 SO2 and 1.10 ± 0.07 µg m− 3 NO2) and higher concentrations in industrial areas (20.0 ± 1.3 µg m− 3 SO2 e 21.0 ± 1.3 µg m− 3 NO2).  相似文献   

13.
Using the U(4) algebraic model, in this work we report a study of the vibrational spectra of SO2, H2018 and D2O16. The inclusion of intermode couplings in algebraic models has been stated to give a deep insight into detailed spectroscopy for these bent XY2 molecules. Improved set of algebraic parameters has been reported to provide improved RMS deviations for these molecules.  相似文献   

14.
Three photocatalytic oxidation (PCO) systems: C7H16-O2, SO2-O2 and C7H16-SO2-O2 were carried out with the aid of UV-illuminated TiO2 nanoparticles at room temperature in a batch reactor. In C7H16-O2-TiO2 system, no catalyst deactivation was observed, while for SO2-O2-TiO2 and C7H16-SO2-O2-TiO2 systems, the photocatalytic activity of used TiO2 powder showed decreasing and eventually no activity after used consecutively. The reaction products such as sulfur trioxide or sulfuric acid adsorbed onto the surface of TiO2 catalyst were poisoning species. Photocatalytic activity of the deactivated TiO2 powder could be regenerated by sonicating treatment with water and methanol for the two systems, respectively.  相似文献   

15.
16.
TPD, XPS IR methods were used to study how the composition of mixed Pt and Pd contacts over Al2O3 affects the nature of SO2 complexes formed in the presence of O2. Two types of sulfates of different structure and binding strength are formed in SO2 oxidation by oxygen over Pt and Pd contacts. Introducing elements such as Co and Cr into the composition, one can significantly reduce the formation of weakly binding sulfate-1 as well as sulfate-2 too.  相似文献   

17.
Oxidation of cis-1-transoid-1,2-cis-2-3,4,7,8-tetra-tert-butyl-9,10-dithiatricyclo[4.2.1.12,5]deca-3,7-diene 9,10-dioxide (2) by dimethyldioxirane gave the corresponding tetraoxide 4 quantitatively, which in turn provided 1,4,5,8-tetra-tert-butyl-1,3,5,7-cyclooctatetraene (6a) quantitatively by twofold thermal SO2 extrusion. The molecular structure of 6a is described on the basis of DFT calculations (B3LYP/6-31G(d) level) and X-ray crystallographic analysis.  相似文献   

18.
According to the basic research performed using a small size reactor at TRCRE of JAERI, the electron beam irradiation process was proved to be very effective for NOx, SO2 and HC removals from flue-gas of municipal waste incinerators. Based on this result, a pilot-plant was constructed for the demonstration of NOx, SO2 and HC removal performance using electron accelerator of maximum energy 0.95 MeV and maximum power 15kW.The pilot-plant was constructed at Matsudo City waste Disposal Center. The flue-gas of 1,000 Nm3/hr is guided from the waste incinerator flue-gas line of 30,000Nm3/hr to the pilot-plant to be processed by spraying Ca(OH)2 slurry or powder and irradiation with high-energy electron beam of the accelerator. NOx, SO2 and HC are removed simultaneously from the flue-gas by the enhanced reaction with Ca (OH)2 under irradiation.A brief explanation of the pilot-plant and preliminary results of the experiments are introduced in this paper.  相似文献   

19.
以硫酸盐为原料,添加NaOH和NaHCO3以制备出碱式碳酸盐前驱体,合成出新型的纳米固体超强酸催化剂SO42-/ZnFe2O4,经XRD、BET、IR等检测,粒径为35nm,比表面积很大(137m2-1),粒度均匀。首次以该固体酸为催化剂,癸二酸和无水乙醇为原料合成癸二酸二乙酯,考察了影响反应的因素。结果表明,醇酸摩尔比为4.0∶1,催化剂用量为1.0g(癸二酸0.1mol),带水剂苯15mL,反应时间2.5h是最佳反应条件,酯化率可达91%,并推断出该催化剂的酸强度-16.02< Ho< -14.52.  相似文献   

20.
以Al2O3为基质,添加ZrO2和La2O3,制成La2O3-ZrO2-Al2O3复合载体,然后采用SO42-进行改性,再负载上Cu2+,制备了铜基SO42-改性的复合载体催化剂(Cu/SO42-/La2O3-ZrO2-Al2O3)。考察了它在富氧条件下对丙烯选择还原NO的催化性能,并借助XRD、SEM、TG、Py-IR、NH3-TPD、FTIR和TPR等方法研究了Cu/SO42-/La2O3-ZrO2-Al2O3的结构和性能的关系。结果表明,ZrO2的加入主要有利于提高催化剂的低温活性;La2O3的加入则主要有利于提高催化剂的热稳定性和还原性能;SO42-能够与Zr形成螯合双配位结构,大幅度促使催化剂表面酸量增加并且酸性增强;因此,有效地提高了Cu/SO42-/La2O3-ZrO2-Al2O3在富氧条件下对丙烯选择还原NO的催化活性和水热稳定性。在无水条件下,Cu/SO42-/La2O3-ZrO2-Al2O3能使NO的最大转化率高达84.3%,即使在275 ℃ 10%水蒸气存在的情况下,仍能使NO的转化率高达81.2%。  相似文献   

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