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641.
稻草改性的红外光谱分析 总被引:4,自引:0,他引:4
利用红外光谱对稻草改性的生成物进行分析,可以确定纤维素是否发生改变及生成何种物质. 相似文献
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为了提高室内环境空气质量,本论文开展了光催化剂制备的研究。本论文采用溶胶-凝胶法制备B/Y3+共掺杂TiO2复合光催化材料,以甲醛为降解物质,在紫外和可见光下分别研究了复合催化剂的光催化活性,对不同掺杂对光催化活性的影响、光催化剂的稳定性进行了分析。B/Y3+共掺杂TiO2复合光催化材料大大提高了催化剂的活性,对甲醛降解有较高的效率。 相似文献
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For direct gas to liquid (GTL),a novel process producing energy sources for methane dehydroaromatization is needed.Supporting MoO3 on H-MFI zeolite shows the high catalytic capacity and a selective activity for dehydroaromatization of methane to benzene at 973 K in a fixed bed reactor.On the other hand,deactivation by coke on the active sites in all the catalysts is formed during the reaction.H2 co-feed suppressed the deactivation,which is probably due to the decrease in coking amount.Mo K-edge X-ray absorption fine structure (XAFS) results showed the formation of dispersed Mo2C species with low crystallinity after dehydroaromatization.Mo L-edge XANES (X-ray absorption near-edge structure) indicated the formation of active Mo species including Mo2C and Mo-oxycarbide (MoOxCy),where the red-ox state should be independent in the absence/presence of H2.It is concluded that Mo-oxycarbide species act as highly active species,and their stability affected the durable activity in the presence of H2. 相似文献
649.
Electrochemical incineration of dimethyl phthalate by anodic oxidation with
boron-doped diamond electrode 总被引:1,自引:0,他引:1
The anodic oxidation of aqueous solutions containing dimethyl phthalate (DMP) up to 125 mg/L with sodium sulfate (Na2SO4) as
supporting electrolyte within the pH range 2.0–10.0 was studied using a one-compartment batch reactor employing a boron-doped
diamond (BDD) as anode. Electrolyses were carried out at constant current density (1.5–4.5 mA/cm2). Complete mineralization was
always achieved owing to the great concentration of hydroxyl radical (.OH) generated at the BDD surface. The e ects of pH, apparent
current density and initial DMP concentration on the degradation rate of DMP, the specific charge required for its total mineralization
and mineralization current e ciency were investigated systematically. The mineralization rate of DMP was found to be pH-independent
and to increase with increasing applied current density. Results indicated that this electrochemical process was subjected, at least
partially, to the mass transfer of organics onto the BDD surface. Kinetic analysis of the temporal change of DMP concentration during
electrolysis determined by High Performance Liquid Chromatography (HPLC) revealed that DMP decay under all tested conditions
followed a pseudo first-order reaction. Aromatic intermediates and generated carboxylic acids were identified by Gas Chromatography-
Mass Spectrometry (GC-MS) and a general pathway for the electrochemical incineration of DMP on BDD was proposed. 相似文献
650.
活化处理活性炭纤维的表面特性及其汞吸附性能 总被引:6,自引:0,他引:6
选用了3种比表面积不同的粘胶基活性炭纤维(ACF-1、ACF-2和ACF-3),并对样品ACF-1进行了浓硝酸和氨水活化处理,获得样品ACF-N和ACF-NH3,最后对这5种ACF样品进行表面特性表征和单质汞的吸附实验.氮分子吸附(77.4K)实验结果表明,ACF-N和ACF-NH3的微孔容积与ACF-1相比有所减小,各样品的微孔(d2nm)分布有一定差异.ACF含有许多不规则的表面微结构,其X射线光电子能谱(XPS)分析表明,ACF-N的含氧官能团(CO、COOH)和ACF-NH3的含氮官能团含量与ACF-1相比均有明显增加.X射线衍射(XRD)分析结果表明,ACF-2和ACF-3的石墨化程度和晶体化程度较ACF-1有所提高.汞吸附实验表明,由于受到ACF表面微结构的影响,微孔容积与吸附能力之间并非简单的依附关系,增加含氧、含氮基团含量在一定程度上能提高ACF的汞吸附容量. 相似文献