Mesoporous carbons with ordered channel structure (COU-1) have been successfully fabricated via a direct carbonization of an organic-organic nanocomposite.The discovery of nanostructured carbon materials such as fullerenes 1 and carbon nanotubes 2 has led to a considerable interest in the development of various carbonaceous materials. In particular, porous carbonaceous materials have been attracting much attention because of their high surface areas, large pore volumes, chemical inertness and high mechanical stability. Porous carbons show promise in the fields of hydrogen-storage, catalysis and electrochemistry. Many researchers have reported control of such pore structures through the template method, using various inorganic porous materials such as alumina membranes, 3 zeolites, 4-6 siliceous opals 7 and silica xerogels. 8 Recently, various types of ordered mesoporous carbons (OMCs) have been generated via a multistep synthetic procedure, in which ordered mesoporous silicas (OMSs) are employed as hard templates. [9][10][11][12][13][14][15] The most common synthetic route yielding OMCs involves preparation of OMS templates, impregnation of the OMS pores with carbon precursors, carbonization, and removal of the templates ( Fig. 1(A)). The removal of the OMS templates can be performed through a treatment with HF solution, converting the carbon into a porous form, while retaining the nanostructural features of the OMSs.In contrast, our novel OMC synthesis route, reported here, avoids the use of hard templates, and could thus reduce the number of preparation steps and the cost involved in producing these materials. Our strategy is to use an organic-organic interaction between a thermosetting polymer and a thermallydecomposable surfactant to form a periodic ordered nanocomposite. The thermosetting polymer is carbonized by heating under N 2 , after which process it remains as a carbonaceous pore wall ( Fig. 1(B)). Resorcinol/formaldehyde (RF) and triethyl orthoacetate (EOA) were used as the carbon co-precursors and triblock copolymer Pluronic F127 was used as a surfactant (Fig. 1(C)). The resultant materials are referred to as COU-1.In a typical synthesis, 0.661 g resorcinol was completely dissolved in a mixture composed of 1.74 g deionized water, 2.3 g ethanol and 0.06 ml hydrochloric acid (5 mol l 21 ). Then, 0.378 g Pluronic F127 was added to the resorcinol solution. After the complete dissolution of the Pluronic F127, 0.487 g of triethyl orthoacetate and 0.541 g of formaldehyde was added to the solution, and stirred at 30 uC for 20 min. The resultant solution was added dropwise to a silicon substrate spinning at 50 rpm, and then the substrate was spun up to 1000 rpm for 2 min. For polymerization of the resorcinol with formaldehyde, the asdeposited sample was heated at 90 uC for 5 h, in air. Then, the resultant brown deposit was carbonized under a nitrogen atmosphere at 400 uC for 3 h at a heating rate of 1 uC min 21 , followed by further carbonization at 600 and 800 uC for 3 h.{ Electronic supplementary informati...

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Nano-phase transition of an organic−inorganic nanocomposite under vapor infiltration of tetraethoxysilane (TEOS) or tetramethoxysilane (TMOS) was found in mesoporous thin film preparation. The rearrangement into a hexagonal periodic structure implies high mobility of the surfactant−silicate composites in solid phase. The swelling of film thickness and d spacing was observed under vapor infiltration. The nano-phase transition under vapor infiltration contains two competitive processes:  (1) the penetration of TEOS or TMOS into the film and (2) the reaction of the silanol group. Film thickness and d spacing were controlled by changing synthetic temperature, silica sources (TEOS and TMOS), catalysts (HCl and NH3), and the thickness of surfactant films. The films prepared from vapor phase show superior characteristics, such as high structural stability and high resistance to water adsorption. The vapor infiltration method is a simpler process than conventional sol−gel techniques and attractive for mass production of a variety of organic−inorganic composite materials and inorganic porous films.

The l ( m , n ) term simplifies considerably for specified odd or even values of m and n. This is displayed in the following result for F 2 ( 2 ) which is obtained from Equation (23 ) :The following results have been obtained for l ( h m , A n ) : l ( m , n ) = ( -1 P v ( n -m ) ( n + m + l )[(Sn + 1 ) Coshmyc -(en + 1 ) Cos hmyc -( -1 ) m ( 2 m + 1) Sinlnyc + (-1)" (ern + 1) Sin hmyc] (C11) for m =j= n. As before, this is indeterminate for n = m, and an alternate result is needed:The equation of motion for the two phase flow within a bubble column, operated within the recirculation flow regime, has been solved, and the profile of liquid flow has been determined. Nicklin's relation for the bubble flow regime has been extended to the recirculation flow regime.Data analysis shows that the mean slip velocity between bubble and liquid is approximately constant and that the kinematic turbulent viscosity increases rapidly with increasing diameter of the column. These observations lead to the conclusion that scale-up has but little influence upon the mean gas holdup SCOPE It is well known that a swarm of bubbles rises uniformly within a gas bubble column when the superficial gas velocity is low (usually less than 2 to 4 cm/s) and