太阳能吸附式空气取水器的技术方案及其理论和实验研究

报道了一种太阳能吸附式空气取水器的技术方案，对其进行了原理分析和实验验证。     

Flux pattern and fouling of membranes during ultrafiltration of some dairy products

The flux pattern of milk (whole milk, skimmed milk and buttermilk) showed a distinct contrast to whey (sweet whey and acid casein whey) systems during ultrafiltration (UF) at constant composition. For milk systems, the initial flux was lower than for whey systems, but the flux stabilised within a few minutes of operation. However, for both acid and sweet whey, the flux continued to fall with time for nearly 1 h. The fouling coefficient (FC) for buttermilk was 0.6 after 5 min, rising to 0.68 after 60 min. During this time flux did not decline, suggesting that concentration polarisation (CP), rather than fouling, was controlling the flux rate. In contrast, the FC for whey was 0.5 after 5 min with a progressive rise over the next 55 min, but the flux also fell throughout this period suggesting that flux was controlled by fouling rather than CP. The higher concentration of protein in milk systems appeared to be responsible for CP, rather than fouling, being the controlling mechanism.     

Time-dependent competitive adsorption of milk proteins and surfactants in oil-in-water emulsions

Competitive adsorption of pure milk proteins and non-ionic surfactants has been studied in model oil-in-water emulsions (4 g kg^?1 β-lactoglobulin or β-casein, 200 g kg^?1 n-hexadecane) as a function of the age of the adsorbed protein layer at the oil-water interface. With β-lactoglobulin-stabilised emulsions containing oil-soluble surfactant C₁₂ E₂ (diethylene glycol n-dodecyl ether), there is found to be a steadily increasing amount of protein associated with the emulsion droplets over a few hours following emulsification. Addition of water-soluble surfactant Tween 20 (polyoxyethylene (20) sorbitan monolaurate) to a β-lactoglobulin-stabilised emulsion (with or without C₁₂E₂) leads to less protein displacement if the emulsion is aged prior to addition of Tween 20. Moderate additions of C₁₂E₂ or Tween 20 produce no time dependence in the competitive adsorption in β-casein-stabilised emulsions, although some time dependence is observed when C₁₂E₂ and a high concentration of Tween 20 are present together. Crystallisation of the oil phase in β-casein-stabilised emulsions at pH 7 leads to a lowering of the measured protein surface concentration, especially in the presence of C₁₂E₂ and a reduction in the surfactant to protein molar ratio required for complete protein displacement by water-soluble surfactant (Tween 20 or octaethylene glycol n-dodecyl ether). Under more acidic conditions of pH 5 or pH 3, the surface coverage and ease of displacement of β-lactoglobulin at the surface of liquid emulsion droplets is substantially different from that under neutral pH conditions.     

漂白麦草浆细杂组份对阳离子淀粉吸附的影响

本文研究了漂白麦草浆中细杂组份(通过100目,其中大部分是杂细胞,如薄壁细胞,表皮细胞)对阳离子淀粉吸附的影响。 实验表明,漂白麦草浆中细杂组份的比表面积明显大于纤维组份(保留在100目以上)的比表面积。阳离子淀粉优先吸附在比表面积大的细杂组份上。纤维组份的吸附能力受化学环境的影响较细杂组份更为敏感。     

4—氨基—三氮唑树脂对钼（Ⅵ）的吸附性能及其机理研究

在Ph=5.0的Hac-NaAc体系中,4-氨基-三氮唑树脂(4-ATR)对Mo(Ⅵ)有较好的吸附性．静态饱和吸附容量As=189.5mg/g·R,用1～3moll-1Ha可以将吸附的Mo定量洗脱．298K测得吸附热力学参数△H=-27.3kJ·mol     

分子筛用于丙炔/丙烯的高效分离

为解决传统的丙炔/丙烯分离能耗高,制约丙烯生产效率的问题,探讨了几种孔径尺寸接近的5A分子筛、4A分子筛和Silicalite 1分子筛对丙炔/丙烯的分离性能,通过吸附分离的方式,实现了高效的丙炔/丙烯分离。详细考察了5A分子筛、4A分子筛和Silicalite 1分子筛〖JP2〗在273 K和298 K下对丙炔/丙烯的单组分吸附性能,并进行了选择性计算。对5A分子筛、4A分子筛和Silicalite 1分子筛进行了模拟固定床的丙炔/丙烯(V〖DK〗(C3H4)∶V(C3H6)〖JP〗=1∶99)混合气穿透实验。结果表明,5A分子筛具有最优的分离效果。实现了基于分子筛对丙炔/丙烯的高效分离,为分子筛在低碳烃的分离应用提供了新的方向。     

氮取代对环状烃在H-FAU分子筛中吸附性能的影响

催化裂化原料中的含氮杂环化合物吸附能力强、扩散阻力大,是造成分子筛催化剂中毒失活的重要因素。选取吡啶和哌啶两种含氮杂环化合物及与其结构相似的苯和环己烷两种环状烃为模型化合物,采用蒙特卡罗（GCMC）和密度泛函（DFT）方法考察了4种化合物在H-FAU分子筛孔道和酸性位上的吸附行为。结果表明：4种分子主要分布在超笼孔道中,其中两种氮化物的分布更加集中;吸附强度由高到低的顺序为：哌啶＞吡啶＞苯＞环己烷,并且氮化物与分子筛活性位之间是化学吸附,苯和环己烷的吸附是物理吸附。电荷密度分布结果揭示了两种氮化物分子与H质子之间发生不同程度的电荷转移。模拟结果可为分子筛催化剂氮中毒机理的研究提供理论指导。     

On the practicability of a new bio sorbent: Lasani sawdust and coconut coir for cleanup of oil spilled on water

In this article, two bio-sorbents have been selected: lasani sawdust (LS) (a new bio-based material) and coconut coir (CC) for the removal of used motor oil from the aqueous phase. The physical nature of the materials was characterized using Fourier Transform Infrared Spectroscopy and Constitutional Analysis of lignin and cellulose. The adsorption process was evaluated using various kinetic and adsorption models. The evaluated sorption capacities for coconut coir and lasani sawdust were 12.82?g g^?1 and 0.36?g g^?1, respectively. Maximum sorption of oil from the aqueous solution conveniently took place in 20?minutes. To ascribe statistically which model describes the adsorption phenomenon best, Root Mean Square Error (RMSE) and Average Relative Error (ARE) were used. The kinetics of the adsorption was best described by Pseudo-second order. Similarly, Langmuir isotherm model had the least value for the two error functions and a higher q_max value for coir than for lasani. It was concluded that the increased absorptive ability of coir over lasani was due to the difference in the composition of lignin and cellulose of the two materials.     

Adsorption kinetics and enhanced oil recovery by silica nanoparticles in sandstone

This study addresses adsorption kinetics of silica nanoparticles on sandstone mineral surfaces and Enhanced oil recovery (EOR) by nanoparticles. It was shown that nanoparticle adsorption on quartz which is the major constituent of sandstone reservoirs was best described as second order process. Both rate and equilibrium adsorption increases with salinity. However, salinity reduces Intraparticle diffusion while enhancing film diffusion. Spontaneous imbibition with nanoparticles dispersed in low salinity water showed higher incremental recovery which may be due to increased structural disjoining pressure. This was supported by surface forces analysis based on particle size and zeta potential measurements of the nanofluids.     

Catalysis by nanoscale gold (Au/MOx): B. Reaction mechanisms of low temperature CO oxidation reactions

Here, in Part B of this Series, we take a critical look at the reaction mechanisms of low temperature CO oxidation reactions over nanoscale gold, including adsorption, surface reaction, and desorption of key substrates, viz., CO and O₂. Based on a concerted analysis of reactivity data of Au nanoparticles, physicochemical surface characterization, and theoretical first principles calculations, we conclusively prove that out of the 2 most commonly invoked reaction mechanisms, gold-only vs. gold-assisted, the latter is the only mechanism operative for supported gold particles in the quantum size range of 2–5?nm. The Au-MO_x support perimeter interface is a structural motif that is very rich in small metallic particles, and extremely low-coordinated Au sites (with N ～4–5), and some in presence of atomic bonding with Zn atoms. There is both charge and species transfer at this perimeter interface, which also provides highly active sites for adsorption of CO and O₂.