Effect of Potassium on Sol-Gel Cerium and Lanthanum Oxide
... Therefore, the catalysts used in the catalytic combustion of soot must be capable of presenting catalyst activity at low temperatures [10]. An important number of catalytic formulations have been developed in this field, including oxides [11]-[14], perovskites [9] [15]-[17], spinels [18] and metals ...
... Therefore, the catalysts used in the catalytic combustion of soot must be capable of presenting catalyst activity at low temperatures [10]. An important number of catalytic formulations have been developed in this field, including oxides [11]-[14], perovskites [9] [15]-[17], spinels [18] and metals ...
A mole
... Where does the number for the unit come from (and why is it often called Avogadro’s number)? ...
... Where does the number for the unit come from (and why is it often called Avogadro’s number)? ...
CO2 Binding and Induced Structural Collapse of a Surface
... of C and H atoms in the aromatic ring of the benzoate units, while all the (x,y,z) coordinates of the CO2 molecule, O atoms in the carboxyl groups of the benzoate units, and Fe atoms are relaxed. As a consequence of these constraints, we cannot describe the influence of the structural changes at one ...
... of C and H atoms in the aromatic ring of the benzoate units, while all the (x,y,z) coordinates of the CO2 molecule, O atoms in the carboxyl groups of the benzoate units, and Fe atoms are relaxed. As a consequence of these constraints, we cannot describe the influence of the structural changes at one ...
File
... 1) What is the formula (molar) mass of Mg(NO3)2? 2) What is the percent oxygen in #1? 3) If the empirical formula is NO2 and the molar mass is 138 g/mol, what is the molecular formula? 4) What volume is 65g of N2 gas at STP? ...
... 1) What is the formula (molar) mass of Mg(NO3)2? 2) What is the percent oxygen in #1? 3) If the empirical formula is NO2 and the molar mass is 138 g/mol, what is the molecular formula? 4) What volume is 65g of N2 gas at STP? ...
Pore Scale Modeling of Rock Properties and Comparison to Laboratory Measurements
... Understanding the interaction between rock matrix, pore space, and pore fluids at microscopic scale is crucial to better interpretation of macroscopic geophysical measurements. With the development of modern imaging techniques, such as advanced X-ray CT and laser confocal microscopy, direct image of ...
... Understanding the interaction between rock matrix, pore space, and pore fluids at microscopic scale is crucial to better interpretation of macroscopic geophysical measurements. With the development of modern imaging techniques, such as advanced X-ray CT and laser confocal microscopy, direct image of ...
Aalborg University 2010
... They are very limited reports where molecular imprinting of inorganic materials are utilized and even less where covalently imprinting have been applied. This report will focus on investigations of covalently imprinted silica networks produced by employing the sol-gel process. Furthermore the effect ...
... They are very limited reports where molecular imprinting of inorganic materials are utilized and even less where covalently imprinting have been applied. This report will focus on investigations of covalently imprinted silica networks produced by employing the sol-gel process. Furthermore the effect ...
TiO2奈米光觸媒濾網應用於空調系統分解甲醛氣體之研究
... performed (Ao, 2004). The photocatalyst titanium dioxide (TiO2) has many advantages related to its high level of photocatalytic activity, high photocatalytic efficiency, low operation temperature, high specific surface area, good chemical stability, and thermal stability, TiO2 used for reaction are ...
... performed (Ao, 2004). The photocatalyst titanium dioxide (TiO2) has many advantages related to its high level of photocatalytic activity, high photocatalytic efficiency, low operation temperature, high specific surface area, good chemical stability, and thermal stability, TiO2 used for reaction are ...
technical report 91 -32
... only phenomenological; they concentrate on adsorption on one particular rock system and discuss it only in terms of the amount that is sorbed without trying to understand the reasons for different adsorption behavior on different rocks. Where a large number of studies is available, the ones with mor ...
... only phenomenological; they concentrate on adsorption on one particular rock system and discuss it only in terms of the amount that is sorbed without trying to understand the reasons for different adsorption behavior on different rocks. Where a large number of studies is available, the ones with mor ...
Heterogeneous nucleation in multi-component vapor on a partially
... the range of surfaces forces and, therefore, the droplet shape can differ from the macroscopic case. The effect of possible precursor film is incorporated into the solid-vapor surface tension. We assume that the range of the intersurface forces diminishes with the size of seed particle so that we ca ...
... the range of surfaces forces and, therefore, the droplet shape can differ from the macroscopic case. The effect of possible precursor film is incorporated into the solid-vapor surface tension. We assume that the range of the intersurface forces diminishes with the size of seed particle so that we ca ...
H2 Adsorption on 3d Transition Metal Clusters
... chemisorption on scandium clusters have been performed. In contrast to this, vanadium clusters have received considerable research interest. The adsorption of H2 and D2 has been studied using flow tube and ion trap techniques.4,13,19-23 The Vn+-D bond energies have been measured by studying the kine ...
... chemisorption on scandium clusters have been performed. In contrast to this, vanadium clusters have received considerable research interest. The adsorption of H2 and D2 has been studied using flow tube and ion trap techniques.4,13,19-23 The Vn+-D bond energies have been measured by studying the kine ...
Catalytic conversion of C(2)-C(3) alcohols on detonation nanodiamond and its modifications
... microscopy, these aggregates consisted of primary particles with approximately spherical form ~5 nm in size (Fig. 1b). It should be noted that the size distribution was rather narrow: all of the primary particles had almost the same size of ~5 nm. It should be noted that large aggregates (>20 µm) ar ...
... microscopy, these aggregates consisted of primary particles with approximately spherical form ~5 nm in size (Fig. 1b). It should be noted that the size distribution was rather narrow: all of the primary particles had almost the same size of ~5 nm. It should be noted that large aggregates (>20 µm) ar ...
Growth Mechanism and Electronic Structure of Zn3P2 on the Ga
... tetragonal Zn3P2 lattice. This indicated that the Zn3P2 film must have had a crystalline phase directly beneath the irregularly shaped overlayer observed in the STM images. Figure 1f displays an STM image of a thick (a few nanometers) Zn3P2 layer. Again the irregular surface features persisted indepe ...
... tetragonal Zn3P2 lattice. This indicated that the Zn3P2 film must have had a crystalline phase directly beneath the irregularly shaped overlayer observed in the STM images. Figure 1f displays an STM image of a thick (a few nanometers) Zn3P2 layer. Again the irregular surface features persisted indepe ...
Adsorption
Adsorption is the adhesion of atoms, ions, or molecules from a gas, liquid, or dissolved solid to a surface. This process creates a film of the adsorbate on the surface of the adsorbent. This process differs from absorption, in which a fluid (the absorbate) permeates or is dissolved by a liquid or solid (the absorbent). Adsorption is a surface-based process while absorption involves the whole volume of the material. The term sorption encompasses both processes, while desorption is the reverse of it. Adsorption is a surface phenomenon.Similar to surface tension, adsorption is a consequence of surface energy. In a bulk material, all the bonding requirements (be they ionic, covalent, or metallic) of the constituent atoms of the material are filled by other atoms in the material. However, atoms on the surface of the adsorbent are not wholly surrounded by other adsorbent atoms and therefore can attract adsorbates. The exact nature of the bonding depends on the details of the species involved, but the adsorption process is generally classified as physisorption (characteristic of weak van der Waals forces) or chemisorption (characteristic of covalent bonding). It may also occur due to electrostatic attraction.Adsorption is present in many natural, physical, biological, and chemical systems, and is widely used in industrial applications such as activated charcoal, capturing and using waste heat to provide cold water for air conditioning and other process requirements (adsorption chillers), synthetic resins, increase storage capacity of carbide-derived carbons, and water purification. Adsorption, ion exchange, and chromatography are sorption processes in which certain adsorbates are selectively transferred from the fluid phase to the surface of insoluble, rigid particles suspended in a vessel or packed in a column. Pharmaceutical industry applications, which use adsorption as a means to prolong neurological exposure to specific drugs or parts thereof, are lesser known.However, it should be remarked that the distinction between adsorption and absorption vanishes as we go from perfectly crystalline macroscopic materials to porous/structured materials, aggregates and composites made out of increasingly smaller grains, viz., micron-sized particles to nanoparticles, sub-nano particles and finally molecules (or atoms). In such nano-composites, the internal surface area of particulate matter is very large. Then the adsorption on internal surfaces simply becomes absorption when viewed from the bulk. Then the distinction between adsorption and absorption vanishes. On the other hand, the distinction is clearest between bulk solids without internal structure, but having only surfaces where only adsorption can occur on the outer surfaces, and nanocomposites or aggregates with internal structure where absorption by the host material is simply adsorption on internal surfaces of the host material. As an example, we may consider a crystalline piece of silicon dioxide (quartz) which can adsorb water molecules on its surface. However, if the quartz is ground into very fine sand, the pile of sand (an aggregate) has a very large internal surface area. A very large amount of water can be adsorbed by the ""internal"" surfaces of the grains in the pile of sand, and this absorption is simply ""internal adsorption. If water is made to flow thorugh such a pile of sand, ions and toxins in the water may be preferentially adsorbed by the surfaces of the grains of sand, providing a simple, well-known water purification application.The word ""adsorption"" was coined in 1881 by German physicist Heinrich Kayser (1853-1940).