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The ever-growing demand for sustainable energy and chemicals associated with declining fossil reserves motivates the quest for alternative feedstocks and processes. Short-chain olefins have numerous end-uses in the polyolefin industry and need to be supplemented or integrated with an alternative process to meet future demands. This work demonstrates that single-cell oil (SCO) derived from the oleaginous yeast Rhodotorula mucilaginosa IIPL32 could be a renewable feedstock for olefin production. A PtSn/alumina catalyst provided 60–70% gas yield, which consisted of ∼55–60% C2–C4 olefins. High selectivity to C2–C4 olefins is attributed to the selective catalytic cracking of long-chain lipid molecules over nanosized PtSn/alumina and the synergy between surface acidic sites and reducible Pt species, which improves the chemical stability and quality of the resulting gaseous hydrocarbon. [ABSTRACT FROM AUTHOR]

Intrinsic structural characteristics of porous materials have found significant applications in selective separation of gases and heterogeneous catalysis. While using porous materials for gas separation and catalysis, some of the challenging issues are the strength of catalytic sites, hydrothermal stability, crystalline order of solids, and selectivity. Researchers' ability to engineer the synthesis strategies rationally can help overcome technological challenges. In recent years, breakthroughs in porous materials are focused on developing different chemistries to control the pore architecture. This review focuses on recent advances made in synthesis strategies of porous materials and their impact on gas separation and catalysis applications. A significant part of this review is devoted to various synthesis methods, such as various types of templating methods, molecular layer deposition, sol–gel technique, and polymerization methods. Improvement in various catalytic reactions and gas separations due to different functionalization methods is also summarized. Lastly, we have discussed the applications of porous materials in the form of adsorbents and membranes in commercial processes. We hope that this review will serve as a quick reference for beginners who want to synthesize porous materials with control of pore structure. [ABSTRACT FROM AUTHOR]

A novel catalyst composed of silver nanoparticles grafted on WCN x has been prepared by using a facile pH-adjusted method. The material reported in this study presents a non-mineral acid route for the synthesis of the industrially significant monomer adipic acid through the selective oxidation of cyclohexene. Ag has been stabilized in the hydrophobic matrix during the formation of the mesoporous silica material by using aniline as stabilizing agent. A cyclohexene conversion of 92.2 % with 96.2 % selectivity for adipic acid was observed with the AgWCN x-2 catalyst, therefore, the AgWCN x catalyst was found to be efficient for the direct conversion to adipic acid with respect to their monometallic counterparts. The energy profile diagrams for each reaction path by using the AgWCN x catalyst were studied along with their monometallic counterparts by using the Gaussian 09 package. The reported material can avoid the use of harmful phase-transfer catalysts (PTC) and/or chlorinated additives, which are two among other benefits of the reported work. [ABSTRACT FROM AUTHOR]

We report an easy and versatile route for the synthesis of the parent phase of the newest superconducting wonder material, i.e., p-terphenyl. Doped p-terphenyl has recently shown superconductivity with transition temperature as high as 120 K. For crystal growth, the commercially available p-terphenyl powder is pelletized, encapsulated in an evacuated (10 Torr) quartz tube and subjected to high-temperature (260 C) melt followed by slow cooling at 5 C/h. A simple temperature-controlled heating furnace is used during the process. The obtained crystal is one piece, shiny, and plate like. Single crystal surface XRD (X-ray diffraction) showed unidirectional (00 l) lines, indicating that the crystal is grown along the c-direction. Powder XRD of the specimen showed that as grown p-terphenyl is crystallized in monoclinic structure with space group P2 /a space group, having lattice parameters a = 7.672 (2) Å, b = 5.772 (5) Å, and c = 13.526(3) Å and β = 91.484 (3). Scanning electron microscopy (SEM) pictures of the crystal showed clear layered slab-like growth without any visible contamination from oxygen. Characteristic reported Raman active modes related to C-C-C bending, C-H bending, C-C stretching, and C-H stretching vibrations are seen clearly for the studied p-terphenyl crystal. The physical properties of the crystal are yet underway. The short letter reports an easy and versatile crystal growth method for obtaining quality p-terphenyl. The same growth method may probably be applied to doped p-terphenyl and to subsequently achieve superconductivity to the tune of as high 120 K for the newest superconductivity wonder, i.e., high- T organic superconductor (HTOS). [ABSTRACT FROM AUTHOR]

Abstract: On a special focus, we have fabricated N2 doped mesoporous ordered CNx material using hexagonal SBA‐15 as hard template through polymerisation of hexamethylene tetramine precurssor. The synthesised materials exhibit a very high specific surface area 1332 cm3/g and pore volume 1.12 cc/g. The HR‐TEM shows the succesful replication of silica template i.e, tubular structure of material. The catlytic activity of material has been tested for Knoevenagel condensation reaction of benzaldehyde and ethyl cyanoacetate. Almost 93 % conversion of benzaldehyde has been achieved within 20 min of reaction at room temperature with ≥99.9 % product selectivity. [ABSTRACT FROM AUTHOR]

A boron- and nitrogen-co-doped mesoporous carbon (BxCN) material with a hierarchical pore structure has been synthesized from a new boron precursor via a nanocasting approach. The newly synthesized material was thoroughly characterized by different characterization techniques. It was observed that the BxCN material has an excellent specific surface area, versatile pore diameter and large pore volume. Moreover, the pore diameter can be tuned by varying the amount of the boron source. By using solid-state MAS NMR and XPS, we demonstrated the N–B–C-type structure of the material. The material presented here has excellent stability under an oxygen atmosphere and we also confirmed the catalytic proficiency of this newly developed material in C–H bond activation reactions. The mesoporous BxCN material displays promising catalytic activity for the oxidative dehydrogenation of propane (6.7%) with excellent selectivity for propylene (84.6%) without the presence of any metal. [ABSTRACT FROM AUTHOR]

Here, we report the comparison of the upper critical fields of different superconductors being calculated by two different theories, i.e. Werthamer Helfand Hohenburg (WHH) and Ginzberg Landau (GL). All the samples are synthesized through previously known solid-state reaction route. Phase purity is determined from the Rietveld refinement of powder X-ray diffraction (XRD) data. High-field (up to 14 T) magneto transport ρ( T) H of different superconductors is studied to estimate their upper critical field ( H). The present intercomparison covers from cuprates (YBaCu O)-borides (MgB)-Fe pnictides (NdFeAsO F) and chalcogenides (FeSeTe) to robust NbPdS. The upper critical fields [ H( T)] at zero temperature are calculated by extrapolating the data using GL and WHH equations. [ABSTRACT FROM AUTHOR]

WO x nanoclusters (2-3 nm) embedded on a mesoporous nitrogen-rich carbon material were synthesized by using novel methodology. This material was very effectively capitalized as a new carbon-based acid-base cooperative catalyst for sequential acetal hydrolysis and Knoevenagel condensation reactions. The protocol was also explored for the nitroaldol condensation reaction. [ABSTRACT FROM AUTHOR]

Uniform free standing TiO 2 nanostructure with different shapes was extensively prepared by a template assisted hydrothermal method by controlling the pH and using Ti[OCH(CH 3 ) 2 ] 4 as the titanium source. {101} and {200} planes of TiO 2 were found to be the preferentially exposed active crystal planes for both nanospheres and nanostrips TiO 2 . The newly synthesised TiO 2 materials were found to be very efficient for the photocatalytic degradation of organic pollutants in industrial wastewater. [ABSTRACT FROM AUTHOR]