Zeolite X was synthesized from fly ash under optimized conditions, which supported with Mn, Ce, and Mn-Ce respectively. Fly ash-derived zeolite catalysts exhibited similar catalytic performance as compared the commercial catalyst. XRD, N2 adsorption, SEM, XPS, H2-TPR were used to investigate relationship among structure, physicochemical properties, activities of catalysts. Finally, mechanism NH...

The oxidation of CO has attracted great interest in recent years because of its important role in enhancing the catalyst durability in fuel cells and in solving the growing environmental problems caused by CO emission. The usually used noble metal nanocatalysts are costly and require high reaction temperature for efficient operation. We report here a density functional theory (DFT) study of low...

The studies of Gorter (1), Hughes and Rideal (2), Neurath (3), and Langmuir (4) have shown that proteins are capable of forming surface films of a thickness and area independent of the diameter of the molecule. Depending on the pH and salt concentration of the solution upon which the protein is spread, the surface area may be more than 5 times greater than that to be expected from a monolayer o...

A critical step toward the rational design of new catalysts that achieve selective and efficient reduction of CO2 to specific hydrocarbons and oxygenates is to determine the detailed reaction mechanism including kinetics and product selectivity as a function of pH and applied potential for known systems. To accomplish this, we apply ab initio molecular metadynamics simulations (AIMμD) for the w...

It was shown in preceding papers (2, 3) that when 3,4-benzpyrene dissolved in benzene was irradiated with monochromatic radiation of wave length 2,537 A. in the presence of oxygen, at least two water-soluble substances were included in the products and that these could be recognized, and some of their properties deduced, by spectrophotometric methods. The first, substance A, was characterized a...

hysteresis has been widely recognized in the soil water relationship. in this paper, a detailed review of hysteresis was performed in relation to its models. so far, different models have been suggested to describe hysteresis in the water retention curve (wrc) that could be categorized into two main groups: conceptual and empirical models. the models in the first group are based on the domain t...

Single atom catalysts (SACs) are highly desirable for the effort to maximize the efficiency of metal atom use. However, the synthesis of SACs is a major challenge that largely depends on finding an appropriate supporting substrate to achieve a well-defined and highly dispersed single atom. This work demonstrates that, based on the density functional theory (DFT) calculation, graphyne is a good ...

Aerosols and clouds play central roles in atmospheric chemistry and physics, climate, air pollution, and public health. The mechanistic understanding and predictability of aerosol and cloud properties, interactions, transformations, and effects are, however, still very limited. This is due not only to the limited availability of measurement data, but also to the limited applicability and compat...