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First- and second-generation hydroxyl-terminated dendrimers were prepared starting from a 1,3-diaminopropane core and sulfonimide linkers. A first-generation mesitylene-derived dendrimer was also prepared with the same terminals. The dendrimers were then reacted with Fe3+, Al3+, and UO22+ separately in order to apply the dendrimers for binding these metals, which have important industrial applications and pose environmental problems simultaneously. The prepared dendrimers were also shown to bind Fe3+ selectively from mixtures with Al3+. [ABSTRACT FROM AUTHOR]

The paper presents the results of neutron-physical calculations for determining the optimum configuration of materials for use as a cryogenic moderator in a DARIA university-grade compact neutron source. It is shown that a cryogenic moderator based on a solid frozen mesitylene of a certain configuration may represent the optimum source of cold neutrons for studying the structure and properties of substances by neutron-physical methods in the DARIA neutron source. [ABSTRACT FROM AUTHOR]

The catalytic properties of mesoporous amorphous titanosilicate Ti–Si in acetone homocondensation at 250–350°С and mass feed space velocity of 0.5–10 h–1 were studied. The acetone conversion was 13–52 wt %, and the selectivity with respect to mesitylene was 52–70 wt %. A kinetic model based on the experimentally developed scheme of chemical transformations was constructed; it includes 10 steps and takes into account the effect of water. The retrieval of the kinetic parameters was implemented in the form of a global optimization problem, which allowed determination of the kinetic constants, adsorption constant, activation energy, and heat of adsorption of water. [ABSTRACT FROM AUTHOR]

The innovation of novel chemosensor probes for the recognition of trace volatile organic compounds is critical due to their hazardous effect on the environment and human health. A nitro-group integrated quinoxaline probe with a profound discriminative fluorescence 'turn-on' response to mesitylene was fabricated into guar gum and i-carrageenan, two biopolymer-based hydrogel matrices, to develop compact, portable fluorogenic hydrogel sensors and assess their fluorescence properties. A comparative characterization-based analysis of native, probe-associated, and probe-analyte-associated hydrogels, (comprising of FT-IR, XRD, TGA) was investigated to ascertain the overall compatibility of the hydrogel-based sensors for use as a smart rapid detection tool. Dynamic rheological measurements also validated the mechanical stability and robustness of the developed hydrogel matrices. Fluorescence spectroscopic investigations yielded promising results of 0.15 ppm limit of detection (LOD) in guar gum and 0.29 ppm LOD in i-carrageenan hydrogels respectively. FESEM and Fluorescence microscopy studies represented the morphological variations of the hydrogel sensors on interaction with mesitylene. The practical feasibility of the chemosensor in hydrogel form for mesitylene detection in the vapor phase was also explored. Probe-embedded hydrogels with injectable property was shown, depicting its use as security ink for information encryption functions. This approach of incorporating chemosensors into biobased hydrogel networks has the potential to broaden its opportunities in the field of chemical, biomedical, and environmental sensing sectors. Quinoxaline probe embedded injectable guar gum and i-carrageenan fluorogenic hydrogels produce excellent discriminative fluorescence 'turn on' response towards mesitylene vapor. [Display omitted] • Nitro-quinoxaline probe incorporated guar gum and i-carrageenan based hydrogels • Discriminative fluorescence emission enhancement towards mesitylene • LOD observed as 0.15 ppm in guar gum and 0.29 ppm in i-carrageenan based hydrogels • Vapor phase sensing demonstrated successfully • Hydrogel injectability test performed as 'Security Ink' [ABSTRACT FROM AUTHOR]

Aromatization of alkyl methyl ketones obtained from biorefinery streams is a viable and attractive catalytic pathway to renewable aromatics, precursors for various important monomers and chemicals. To achieve high catalytic activity and stability under continuous conditions, mesoporous amorphous silica-alumina (ASA) catalysts are studied for the acid-catalyzed self-condensation of biomass-derived acetone to mesitylene in solvent-free conditions using a fixed-bed reactor. The catalytic efficiency of ASA catalysts depends on their structure and intrinsic acidity. In comparison to pure alumina, ASA Siralox 30 exhibits a 2.2 times higher catalytic activity for acetone conversion and 3.8 times higher mesitylene yield, demonstrating the importance of Brønsted acid sites (BAS) generated in ASA catalysts. The detailed kinetic studies and catalyst characterization indicate that mesitylene formation is favored over BAS and that the formation rate is enhanced with the relative strength of BAS. We demonstrate here that Siralox 30 (total product selectivity = 66%, W/F = 12.5 gcat h mol−1) is an adequate and highly active catalyst for the continuous mesitylene synthesis with remarkable long-term operational stability (>50 hours-on-stream). [ABSTRACT FROM AUTHOR]

We present experimental results on the loading/unloading working fluid of the cryogenic moderator of a DARIA compact neutron source. A technology for loading liquid nonirradiated mesitylene into a specially designed prototype of the cryogenic moderator chamber and a technology for unloading irradiated mesitylene with a different absorbed dose of ionizing radiation are proposed and experimentally validated. During the experiments, the chamber prototype worked flawlessly in conditions as close as possible to real operating conditions of the cryogenic moderator of a compact neutron source. [ABSTRACT FROM AUTHOR]

• Mesitylene renewable jet-fuel additive by condensation of biomass-derived acetone. • Bench-scale demonstration using TiO 2 and Al-MCM-41 catalyst 1/8″ pellets. • Mass transfer in pellets limited the rate of reaction, so a model was fitted to data. • Mesitylene and isophorone yields were improved with catalyst pellets. • Increase in mesitylene yield by combination of both catalysts in consecutive beds. De-fossilization of the aviation sector will require the use of renewable synthetic jet fuels and additives that comply with strict regulations. One such additive, mesitylene, can be produced using a novel sustainable process based on the fermentation of biomass waste to acetone, followed by the self-condensation of acetone to mesitylene. This study addresses the viability of gas-phase self-condensation of acetone, catalyzed by TiO 2 and Al-MCM-41 acid catalysts, at a technological readiness level of TRL-4. The reactor used was a bench-scale fixed-bed reactor (28 mm diameter and 500 mm height) loaded with commercial-sized catalyst pellets (1/8″ diameter). It was equipped with a jacket for heat transfer using flowing thermal oil. The performance of commercial-scale reactors was approximated under conditions of 275 °C, 280 kPa, and a space velocity of 50–500 mol/kg·h. The catalyst pellets exhibited significant mass transfer resistances, which limited the reaction rate. This, in turn, reduced the deactivation rate caused by the adsorption of high-molecular-weight condensation products on the strongest acid sites. Additionally, the product distribution differed between pellet and powder forms of the catalysts, with higher yields of isophorone and mesitylene being observed on TiO 2 and Al-MCM-41 pellets, respectively. A reaction and mass transfer model was proposed and fitted to the bench-scale data. The study also considered the combination of both catalyst pellets in the same reactor for the bench-scale unit. It was demonstrated that mesitylene yield could be improved, with the best configuration being two separate beds placed consecutively in the reactor with a catalyst ratio of 1:2 (TiO 2 :MCM-41). [ABSTRACT FROM AUTHOR]

Friedel‐Crafts alkylation is one of the most important catalytic reactions in organic chemistry. Recently, hierarchical zeolites have exhibited superior catalytic performance in such liquid‐phase batch reactions. However, for practical application, it is of significance to evaluate their catalytic performance in Friedel‐Crafts fixed‐bed alkylation. In this work, we prepare hierarchical zeolites by post‐treatment, of which the structures are confirmed by XRD patterns and N2 adsorption‐ desorption tests. Then, a fixed‐bed reactor is employed to investigate their catalytic performance in series of benzylation reactions. The results indicate that hierarchical zeolites have superior anti‐deactivation ability in the benzylation reactions, especially when react with p‐xylene or mesitylene, the BA conversion maintained nearly 100 % in 300 min, much better than that of micropore zeolites. These results suggest that hierarchical zeolites have a potential industrial application for Friedel‐Crafts fixed‐bed alkylation than conventional zeolites. [ABSTRACT FROM AUTHOR]

Faujasit‐type zeolites NaX and NaY include a three‐dimensional system of micropores with a pore entrance of 0.74 nm. The dealuminated modification of NaY (zeolite DAY) even contains mesopores. NaX and NaY are applied for technical processes like drying of gases and vapors and for the separation of compounds whereas DAY zeolite acts as fluid‐cracking catalyst. Beside a storage of suitable molecules in the micro‐ and mesopores even larger molecules can be absorbed. Such an enlargement occurs only in microscopic structure defects of the individual zeolite crystals as well as in macroscopic cavities of crystal agglomerates. [ABSTRACT FROM AUTHOR]

The RANS (RIKEN Accelerator driven Neutron Source), one of compact accelerator neutron sources (CANS), tries to expand its performance by installing a cold neutron which may provide new opportunities in many applications. RANS is a low power CANS with a proton beam of 7 MeV and 100 µA at maximum. A moderator system was constructed based on results of optimization design study with mesitylene. Recently, we have done performance tests aiming at showing characteristics as cold neutron source. Cryogenic mesitylene moderator was installed on a plug with a new target moderator reflector configuration of RANS. Experiment using a gas electron multiplier (GEM) detector was carried out to measure neutron spectra of the cold moderator. This paper describes performance of the cold moderator in terms of 1) Cold neutron gain of optimization design with respect to a polyethylene moderator, 2) Temperature dependency of cold neutron spectrum flux regarding scattering kernel (SK), and 3) comparison between experiment and calculation. A note is given for comparison between calculations with different SKs available. Also, two-dimensional imaging of cold and thermal neutron spectrum flux on the viewed surface is shown with a pinhole slit configuration. [ABSTRACT FROM AUTHOR]

The improvement of the neutron intensity of mesitylene cold moderator in KUANS has been conducted in two ways. One is the change of the mesitylene phase by annealing and the other is the optimization of the configuration. The change of the phase of the mesitylene was conducted by keeping the temperature of mesitylene just below its melting point for several hours. It made the cold neutron intensity about 20% larger than that of normally cooled mesitylene. For the configurational optimization, an arrangement giving highest cold neutron intensity was chosen using a Monte Carlo code. The cold neutron intensity measured with this arrangement revealed that its intensity is 3.4 times higher than that for a polyethylene moderator with room temperature. [ABSTRACT FROM AUTHOR]

Three new Metal-Organic Frameworks, containing mesitylene tribenzoic acid as a linker and zinc (1) or cadmium as metals (2,3), were synthesized through solvothermal reactions, using DMF/ethanol/water as solvents, at temperatures of 80 °C (structures 1 and 3) and 120 °C (structure 2). Following single-crystal X-ray diffraction, it was found that 1 and 3 crystallize in the P21/c and C2/c space groups and form 2D networks, while 2 crystallizes in the Fdd2 space group, forming a 3D network. All three frameworks, upon heating, were found to be stable up to 350 °C. N2 sorption isotherms revealed that 1 displays a BET area of 906 m2/g. Moreover, the porosity of this framework is still present after five cycles of sorption/desorption, with a reduction of 14% of the BET area, down to 784 m2/g, after the fifth cycle. The CO2 loading capacity of 1 was found to be 2.9 mmol/g at 0 °C. [ABSTRACT FROM AUTHOR]

A novel, nearly isothermal, nonselective-membrane separation process, membrane vapor extraction (MVE), efficiently recovers butanol from a dilute aqueous solution, for example, from a fermentation broth (Liu et al., 2015). In MVE, feed and solvent liquids are not in contact; they are separated by vapor. Therefore, compared to conventional extraction, MVE avoids formation of difficult-to-separate emulsions. In MVE, a semi-volatile aqueous solute (e.g., butanol) vaporizes at the upstream side of a membrane, diffuses as a vapor through the membrane pores, and subsequently condenses and dissolves into a high-boiling nonpolar solvent, favorable to the solute but not to water. Design analysis of a 1.5-m long, 30-m2membrane-area countercurrent MVE unit for processing 2-wt% aqueous butanol by dodecane solvent at 40 °C indicates over 90% recovery of the feed butanol with essentially no water loss and with very low energy requirement (Liu et al., 2015). The separation factor is over 1500. However, the published design study gives no experimental evidence for the calculated MVE separation. Here, we present experimental data to validate the MVE process. We use an omniphobic (i.e., hydrophobic and oleophobic), 0.2-µm pore-diameter Versapor®200 R membrane (Pall Corporation, Exton, PA) housed in a 6-cm wide by 10-cm long plate-and-frame channeled flow cell with 0.8-cm gap thickness. Membrane transfer area is 28 cm2. The membrane flow cell is designed for minimal axial concentration change and is operated in the transient mode between two recirculating flow loops. 2-wt% aqueous butanol is extracted into dodecane or mesitylene at 25 or 40 °C. Also, 1.5-wt% furfural is extracted into dodecane at 40 °C. Since vapor transport across the membrane contributes minimal resistance, MVE performance is governed by mass transfer through feed and solvent boundary layers. Mass-transfer coefficients are determined from the Graetz-Lévêque analysis of laminar thin-slit flow (Bird et al., 2002). Predicted extraction performance agrees well with experiment using no adjustable parameters. Consistent with the initial multistage-design analysis (Liu et al., 2015), our new bench-scale experimental results confirm that MVE is a viable separation process to recover dilute semi-volatile biosolutes from water with minimal energy requirement. Preliminary analysis of downstream solute recovery from the extract via distillation is more efficient than that for pervaporation because of insignificant water carry over through the MVE membrane.

• Pioneering utilization of nitric acid as a photo-catalyst. • Successful conversion of mesitylene to 3,5-Dimethylbenzaldehyde. • we identify an optimal HNO 3 concentration of 0.2 M for maximizing the yield of 3,5-dimethylbenzaldehyde, highlighting the importance of reaction parameters in photo-catalytic processes. • Mechanistic studies employing scavenger assays suggest the involvement of hydroxyl radicals in the formation of aldehydes. • Synergistic effect with phosphorus corrole photosensitizers. Nitric acid (HNO 3) has garnered attention as a versatile acid reagent in laboratory and industrial settings, primarily known for its role in explosives and fertilizer production. Recent studies have explored its application in catalytic processes, particularly in electro- and photo-catalysis, including its involvement in nitrogen fixation and oxidation. This study investigates the photo-catalytic performance of HNO 3 in the conversion of mesitylene to 3,5-dimethylbenzaldehyde, an industrially significant compound. Our results reveal successful conversion under irradiation conditions, with systematic optimizations indicating an optimal concentration of 0.2 M HNO 3. Mechanistic studies employing scavenger assays suggest the involvement of hydroxyl radicals in the formation of aldehydes. Furthermore, synergistic effects between HNO 3 and phosphorus corrole photosensitizers enhance catalytic performance. Subsequent optimization of reaction conditions yields a maximum yield of 45 % for 3,5-dimethylbenzaldehyde. Expansion of the scope to include toluene derivatives demonstrates varying yields, influenced by substituent effects. Notably, the combination of HNO 3 with the corrole catalyst leads to improved yields compared to HNO 3 alone. These findings underscore the potential of HNO 3 as a photo-catalyst and highlight opportunities for novel catalyst design in practical applications. Mesitylene to 3,5–dimethylbenzaldehyde transformation is successfully conducted via nitric-acid-based photo-catalysis with facile operation. The cooperative synergistic effect is achieved by combining HNO 3 and molecular phosphorus corrole hybrid photo-catalytic system. This work will shed light into new practical applications of HNO 3 industries. [Display omitted] [ABSTRACT FROM AUTHOR]

Nanocomposite sensors were prepared using carbon soot (CNPs), nickel oxide nanoparticles (NiO-NPs), and cellulose acetate (CA), which was used to detect and study the sensing mechanism of mesitylene vapour at room temperature. Synthesised materials were characterised using high-resolution transmission electron microscopy (HR-TEM), powder x-ray diffraction (PXRD), Raman spectroscopy, and nitrogen sorption at 77 K. Various sensors were prepared using individual nanomaterials (NiO-NPs, CNPs, and CA), binary combinations of the nanomaterials (CNPs-NiO, CNPs-CA, and NiO-CA), and ternary composites (NiO-CNPs-CA). Among all of the prepared and tested sensors, the ternary nanocomposites (NiO-CNPs-CA) were found to be the most sensitive for the detection of mesitylene, with acceptable response recovery times. Fourier-transform infrared (FTIR) spectroscopy coupled with an LCR meter revealed that the mesitylene decomposes into carbon dioxide. [ABSTRACT FROM AUTHOR]

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We report the synthesis of a tantalum phosphate catalyst with abundant strong acid sites, which is very active for the catalytic conversion of acetone into mesitylene. Characterizations, kinetic studies, and theoretical results show a relationship between the acidic sites and catalytic performance in this reaction. [ABSTRACT FROM AUTHOR]

The radiochemical and neutron-physical characteristics of a pelletized cryogenic moderator based on a mesitylene mixture (a mixture in the form of frozen pellets) obtained during its operation at the pulsed fast reactor IBR-2 are presented. It is shown that changes in the properties of the mixture at high absorbed-irradiation doses (~100 MGy) have no significant effect on the spectrum of cold neutrons. The gain in the number of cold neutrons from the surface of a cold moderator in comparison with a water moderator reaches 10 times. There is no deterioration in the neutron flux at the end of the reactor duty cycle. If the technology of continuous modification of the working substance in the cryogenic moderator chamber is successfully developed, the frozen mixture of mesitylene and m-xylene can be recommended for use on powerful pulsed neutron sources. [ABSTRACT FROM AUTHOR]

The method of preparing monophosphaferrocenes originally reported by Roberts and Wells, which requires two equivalents of [(mesitylene)FeCp]PF6 (A), was reinvestigated. By the use of inexpensive aluminum chloride as a phenyllithium scavenger, a 50 % reduction of required A could be attained. Diverse monophosphaferrocene derivatives having aliphatic C‐substituents, including four new compounds, were prepared in good yields from the corresponding P‐phenylphospholes, A (1 equiv.), and aluminum chloride (1/3 equiv.) under the modified conditions. These modified conditions showed comparable to better yields of monophosphaferrocenes and the far better atom‐economy compared to the original conditions. [ABSTRACT FROM AUTHOR]

We report a facile synthesis of triarylsulfonium triflates by selective aryl transfer from readily available mesityl iodonium(III) salts to diarylsulfides in the presence of a copper catalyst. The advantage of our protocol is that the iodonium(III) salts bearing a mesitylene (Mes) auxiliary efficiently promote selective S-arylation of diarylsulfides to produce the desired triarylsulfonium triflates without the formation of Mes-derived byproduct salts. [ABSTRACT FROM AUTHOR]

The present study evaluated the abortifacient potential of aqueous-acetone extract of Adenopus breviflorus Benth Seed on the reproductive health of matured female albino rats by monitoring the indices of dysfunctions in reproductive system. Prior to the conduction of the fertility studies, the oral acute toxicity of the seed extract was evaluated for autonomic, behavioral and neurological changes, within 24 h to determine the LD50.The influence of aqueous-acetone extract of Adenopus breviflorus Benth Seed was evaluated for antioxidant, reproductive hormones and histology of uteri tissues primarily to monitor effects in female fertility. Female rats exhibiting thick clump of spermatozoa in their vaginal smear were randomly selected and used for the study to determine the abortifacient activity of the seed extract. Parameters such as number of live and dead fetuses, anogenital distance (AGD) and crown rump length (CRL), and the variation in birth weight of liters and gestation period between control and experimental animals were determined. The phytochemical composition of the seed extract was characterized by Gas Chromatography and Mass Spectrophotometry for the identification of phytochemical of toxic or therapeutic effects. Symptoms similar to clinical toxicity such as salivation, respiratory distress, weight loss and change in appearance of hair were noticed at concentrations above 1600 mg/kg BWT, there was no maternal mortality at any period of the experiment. There were changes in the behavioural, neurological and autonomic profile in groups with doses greater than 1600 mg/kg BWT. The LD50 evaluation showed that the aqueous-acetone extract of the seed was safe at dose of 5000 mg/kg BWT. The GC–MS characterization of the aqueous-acetone seed revealed isomeric derivatives of benzene-mesitylene and pseudocumene 4.28 g/100 g of sample) and 5.85 g/100 g of sample respectively as most predominant phytochemicals in the seed extract which demonstrated maternal toxicity. The effects on the female reproductive hormones of the treated animals revealed that FSH, LH and prolactin were significantly reduced (p

Previously published experimental viscosity data at low density, originally obtained using all-quartz oscillating-disk viscometers for R134a and six vapors of aromatic hydrocarbons in the temperature range between 297 K and 631 K at most, were re-evaluated after an improved re-calibration. The relative combined expanded ( k = 2 ) uncertainty of the re-evaluated data are 0.2 % near room temperature and increases to 0.3 % at higher temperatures. The re-evaluated data for R134a as well as for the vapors of mesitylene, durene, diphenyl, fluorobenzene, chlorobenzene, and p-dichlorobenzene were arranged in approximately isothermal groups and converted into quasi-isothermal viscosity data using a first-order Taylor series in temperature. Then, the data for R134a were evaluated by means of a series expansion truncated at first order to obtain the zero density and initial density viscosity coefficients, η (0) and η (1) . For the six aromatic vapors, the Rainwater–Friend theory for the initial density dependence of the viscosity was used to derive η (0) values. Finally, reliable η (0) and also η (1) values for R134a were selected as reference values in the measured temperature range to be applied when generating a new viscosity formulation. [ABSTRACT FROM AUTHOR]

In order to reduce exposure to toxic chemicals, the European REACH regulation (1907/2006) recommends substituting toxic molecules with compounds that are less harmful to human health and the environment. Toluene is one of the most frequently used solvents in industries despite its toxicity. The objective of this study is to better understand and compare the toxicity of toluene and its homologues in a bronchial cell model. Thus, human bronchial BEAS‐2B cells were exposed to steams of toluene, m‐xylene, mesitylene (1,3,5‐trimethylbenzene), and benzene (20 and 100 ppm). Exposure was carried out using an air–liquid interface (ALI) system (Vitrocell) during 1 h/day for 1, 3, or 5 days. Cytotoxicity, xenobiotic metabolism enzyme gene expression, and inflammatory response were evaluated following cell exposures. BEAS‐2B cell exposure to toluene and its homologues revealed the involvement of major (CYP2E1) and minor metabolic pathways (CYP1A1). A late induction of genes (EPHX1, DHDH, ALDH2, and ALDH3B1) was measured from Day 3 and can be linked to the formation of metabolites. An increase in the secretion level of inflammatory markers (TNF‐α, IL‐6, IL‐8, MCP‐1, and GM‐CSF) was also observed. In parallel, regulation between inflammatory mediators and the expression of transmembrane glycoprotein mucin MUC1 was also studied. This in vitro approach with ALI system points out the relevance of conducting repeated exposures to detect potential late effects. The difference recorded after cell exposure to toluene and its homologues highlights the importance of substitution principle. Human bronchial BEAS‐2B cell exposure to toluene and its homologues (benzene, m‐xylene, and mesitylene) revealed the involvement of major (CYP2E1) and minor (CYP1A1) metabolic pathways and the induction of late genes (EPHX1, DHDH, ALDH2, and ALDH3B1). Secretion of inflammatory markers as TNF‐α, IL‐6, IL‐8, MCP‐1, and GM‐CSF was observed. Regulation between inflammatory mediators and the expression of MUC1 protein was also studied. [ABSTRACT FROM AUTHOR]

Electrocatalysis plays a vital role in industrial processes like electrohydrodimerization of acrylonitrile, anodic substitution and addition, electrolytic oxidative/reductive coupling and electrolysis of heterocyclic compounds. Electrocatalysts with suitable size and shape selectivity for reactants, reactant intermediates and products increase their selectivity. Zeolites are the most common vehicles for size-/shape-selective heterogeneous catalysts, but their lack of electronic conductivity vitiates their use in electrocatalysis. In this context, we explore the effectiveness of carbon derived from the zeolitic imidazole framework (ZIF), which possesses both electronic conductivity and structural selectivity for electrocatalytic oxidative coupling of mesitylene to bimesityl. Co-ZIF synthesized by facile solvothermal method was heated in an inert atmosphere and acid-leached to remove Co in order to generate C-based structured material. Further, Pd acting as a catalyst was deposited inside the pore walls of the obtained C scaffold by electroless deposition to derive pore sizes ranging between the molecular size of the particular product. Controlling the pore size of metastructured electrocatalyst at ~ 16 Å allows only bimesityl formation, and restricts any larger sized by-product. Metastructured electrocatalyst showed ~ 18 times higher selective conversion for the desired bimesityl production than the planar Pd film electrocatalyst, demonstrating the potential of the proposed approach. [ABSTRACT FROM AUTHOR]

Rice husk, rich in silica and abundantly available as waste, is presently destroyed by burning, which creates environmental issues. Thus, it will be advantageous if this rice husk waste can be used for preparation of valuable products. One of the application is its use as silica source in the synthesis of zeolites like ZSM‐5, which are silico‐aluminates. Rice husk waste is available in wide range of particle sizes in agricultural farms. There is no study available in open literature on use of these wide particle ranges for its direct application. This paper is an attempt to use wide particle size rice husk, its effect on ZSM‐5 synthesis and its physico‐chemical properties. Further these prepared ZSM‐5 catalyst was evaluated for benzylation of mesitylene reaction. The study found that, rice husk of 600 μm particle size is optimum as far as ZSM‐5 synthesis, its physicochemical properties and further its application in mesitylene benzylation reaction. [ABSTRACT FROM AUTHOR]

2,4,6-Tris(4-iodophenyl)-1,3,5-trimethylbenzene was synthesized from 2,4,6-triphenyl-1,3,5-trimethylbenzene, using [bis(trifluoroacetoxy)iodo]benzene as the iodinating agent. The title compound was characterized by means of NMR, IR, and mass spectrometry, as well as TG analysis.

Nanocomposite sensors were prepared using carbon soot (CNPs), nickel oxide nanoparticles (NiO-NPs), and cellulose acetate (CA), which was used to detect and study the sensing mechanism of mesitylene vapour at room temperature. Synthesised materials were characterised using high-resolution transmission electron microscopy (HR-TEM), powder x-ray diffraction (PXRD), Raman spectroscopy, and nitrogen sorption at 77 K. Various sensors were prepared using individual nanomaterials (NiO-NPs, CNPs, and CA), binary combinations of the nanomaterials (CNPs-NiO, CNPs-CA, and NiO-CA), and ternary composites (NiO-CNPs-CA). Among all of the prepared and tested sensors, the ternary nanocomposites (NiO-CNPs-CA) were found to be the most sensitive for the detection of mesitylene, with acceptable response recovery times. Fourier-transform infrared (FTIR) spectroscopy coupled with an LCR meter revealed that the mesitylene decomposes into carbon dioxide.

The vapor-liquid equilibrium data are necessary for the design of the distillation columns which separate the mixture mesitylene - ABE components resulting from the liquid-liquid extraction of butanol from the ABE using 1,3,5-trimethylbenzene as solvent. In this work, the vapor - liquid equilibrium data is determined for the binary systems: ethanol + 1,3,5-trimethylbenzene and n-butanol + 1,3,5-trimethylbenzene at constant pressure of 93.325 KPa using a double phase circulation apparatus. Thus, P-T-x-y data is determined, which is further processed by regression to determine the binary interaction parameters of the NRTL and UNIQUAC models. Furthermore, the T-x-y diagrams are calculated using the completed thermodynamic models (NRTL and UNIQUAC) and the UNIFAC predictive model, and compared with the experimental diagrams. [ABSTRACT FROM AUTHOR]

Toluene, p-xylene and mesitylene were cleanly converted to their corresponding monoaldehydes via mild photooxygenation utilizing transition metal and main group β-CF3-substituted corroles. Aldehyde yield increased as more electron-donating CH3 groups are present on the substrate. 4-P was most efficient (TON ∼ 1072, mesitylene) via the singlet oxygen vis the superoxide mechanism. [ABSTRACT FROM AUTHOR]

The design of porous materials for the recognition of multiple hydrocarbons is highly desirable for the energy‐efficient separation and recognition of chemical feedstock. Herein, three new iso‐structural porous discrete metal–organic cages of formula {[Pd3(NiPr)3PO]4(R‐AN)6} (R‐AN=anilate linkers) for the selective recognition of substituted aromatic hydrocarbons are reported. The tetrahedral cages 1, 2, and 3 containing anilate, chloranilate, and bromanilate linkers exhibited selective encapsulation of mesitylene, o‐xylene, and p‐xylene, respectively, over other analogous aromatic hydrocarbons. These selective encapsulations were driven by the variations in the portal diameters present at each of these cages and their interactions with the hydrocarbon guests. These observations are supported by mass spectrometry, NMR studies, and theoretical binding‐energy calculations. [ABSTRACT FROM AUTHOR]

Neutral binuclear metallocycles fac - [{Re(CO) 3 } 2 (CA)(L)] (1 – 2) were obtained using Re 2 (CO) 10 , flexible ditopic phosphine oxide donor 9,10-bis(dimethylphosphonomethyl)anthracene/ 9,10-bis(diethylphosphonomethyl)anthracene (L), and chloranilic acid (H 2 −CA) in mesitylene via one-pot solvothermal methods. The metallocycles were characterized by E.A., FT-IR, ESI-MS and NMR analysis. The solid-state structures of 1 – 2 were confirmed by X-ray analysis which reveal that the complexes adopt binuclear heteroleptic cyclic architectures. The fac - [Re(CO) 3 ] core-based metallocycles 1 – 2 are two of the very few examples of phosphine oxide donor (P = O)-based supramolecular coordination cyclic complexes. Neutral phosphine donor (P = O) clipped fac - [ Re (CO) 3 ] core -based heteroleptic binuclear metallocycles were self-assembled using Re 2 (CO) 10 , rigid bis-chelating ligands and flexible ditopic phosphine donor. [Display omitted] [ABSTRACT FROM AUTHOR]

Sustainable production of jet fuel additives plays an essential role to decrease greenhouse gas emissions in the aviation industry. Acetone obtained from biomass fermentation is one of the platform molecules of the bio-refinery that can be used as raw material of newly developed sustainable processes. Mesitylene jet fuel additive can be obtained by acetone self-condensation reaction catalyzed by porous solids. In the present work, TiO 2 and Al-MCM-41 have been chosen, respectively, as basic and acid catalysts, because of having some tolerance to deactivation. The reaction was studied in a continuous fixed-bed reactor operated in the gas phase at space velocities of 7900 mol/kg h for TiO 2 and 5000 mol/kg h for Al-MCM-41. The influence of feed concentration (5–20% acetone and 0–5% mesityl oxide) and temperature (200–350 °C) was studied. First, the reaction scheme was assessed based on the product distribution. It was found that the acid catalyst Al-MCM-41 favors mesityl oxide decomposition to undesired isobutylene and acetic acid. Then, a mechanistic kinetic model of the different steps of the reaction scheme was developed and fitted the experimental results of each catalyst. This model constitutes a valuable tool for the scale-up of this process. • Mesitylene obtained by condensation of renewable acetone in a fixed-bed reactor. • Acid/base properties of the catalysts are critical for the product distribution. • Mesitylene and isobutylene obtained with Al-MCM-41 acid catalyst. • Mesitylene and isophorone obtained with TiO 2 base catalyst. • Mechanistic kinetic models are developed for both catalysts. [ABSTRACT FROM AUTHOR]

• New data of viscosities of solvent mixtures containing a self-associated liquid. • Composition-temperature dependent interactions in the binary systems. • DFT calculations and FT-IR analysis supported experimental findings. • Theoretical derivation of mixture properties using correlative approaches. Viscosities (η exp) of binary combinations consisting of mesitylene (MES) paired with C7 aliphatic (heptan-1-ol, HepOH) and aromatic (benzyl alcohol, BnOH) alcohols were systematically measured across a range of temperatures (298.15 to 323.15 K; interval, 5 K) under atmospheric pressure conditions (0.10 MPa). Additionally, viscosity deviations (Δ η) from η exp values were calculated and fitted using the Redlich-Kister equation, encompassing the entire span of mole fractions. The η exp values were compared against η cal values predicted by the Grunberg-Nissan, Teja-Rice, and Andrade/DIPPR models. The molecular interactions of MES with HepOH or BnOH were also investigated using Fourier transform infrared spectroscopy. Furthermore, density functional theory, a quantum mechanical approach, was employed to assess intra- and intermolecular correlations among the constituent molecules within the binary mixtures. The findings of the study revealed that the molecular interactions in these mixtures are intricate and dependent on the composition of the mixture. In summary, mixtures of MES with BnOH exhibited stronger interactions than those with HepOH. [ABSTRACT FROM AUTHOR]

First the conformations of various ortho and di-ortho substituted toluenes calculated by quantum chemistry methods are discussed as well as the hindering potentials deduced from the latter results and those established experimentally by microwaves and fluorescence techniques. It appears that methyl (Me) groups are much less hindered in di-ortho than in ortho substituted compounds. Then the study of the 1,3,5-triiodo-2,4,6-trimethylbenzene (triiodomesitylene or TIM) is reported. Density functional theory (DFT) calculations indicate that two conformations of the TIM molecule have the same formation energies. One has C[SUB3h] symmetry, the other with the C[SUBs] symmetry is obtained from the C[SUB3h] by a rotation of 60° for one Me. Experimentally, the TIM structure has been determined at 15 K using single-crystal neutron diffraction data. TIM crystallizes in the triclinic space group P -1. Molecules are stacked in an antiferroelectric manner along the oblique a axis. For two Me groups the experimental conformation is close to the C[SUBs] one, but the third Me group has a C-H bond nearly orthogonal to the ring plane. Such conformation is unstable in the gas state, but it is stabilized in the crystal by intermolecular interactions, nevertheless DFT predicts accurate bond lengths and angles when the Me conformations are constrained to the experimental ones. The three Me groups, having different environments, experience different hindering potentials, this explains why they are tunnelling at different energies as found by inelastic neutron scattering (INS). Using INS results, we deduced the potentials hindering the Me groups rotation in the crystal. The proton probability densities (PPD) calculated from these potentials are in concordance with the crystallographic results. Hence the quantum origin of the broad spreading of PPD observed at 15 K is established. Moreover, it is demonstrated that the crystal field is responsible for the larger part of the potentials... [ABSTRACT FROM AUTHOR]

Bis(1,3,5-trimethylbenzene)gallium(I) tetra-chloridoaluminate(III), [(1,3,5-(CH3)3C6H3)2Ga][AlCl4] (1), bis(1,3,5-trimethylbenzene)gallium(I) tetrabromido-aluminate(III), [(1,3,5-(CH3)3C6H3)2Ga][AlBr4] (2) and (1,3,5-trimethylbenzene)gallium(I) tetraiodidoaluminate(III), [1,3,5-(CH3)3C6H3Ga][AlI4] (3) were synthesized from the corresponding subvalent GaI/AlIII mixed metal halides and characterized via C,H analysis, Raman spectroscopy, X-ray powder diffraction and X-ray single crystal diffraction. Compound 1 crystallizes in the noncentrosymmetric monoclinic space group Cc isotypic to [(1,3,5-(CH3)3C6H3)2Ga][GaCl4]. For 2 and 3 the monoclinic space group P21/n is found, however, they are neither isotypic nor homotypic. While 2 is isotypic to [(1,3,5-(CH3)3C6H3)2In][InBr4], 3 establishes a new structure type. In the solids of all three title compounds coordination polymeric chains are found, in 1 and 2 built up from bis(arene)-coordinated, in 3 from mono(arene)-coordinated Ga+ ions and the corresponding AlX4− anions in a 1κCl:2κCl′ (1), 1κCl,Cl′:2κCl″ (2) or 1κCl,Cl′:2κCl″:3κCl‴ (3) bridging mode. Taking into account the weaker coordinating character of the AlCl4− as compared to the AlBr4− anion, in line with expectations the number of gallium halogen contacts is increased and the strength of the π-arene bonding is reduced in the bromide 2 as compared to the chloride 1. Finally, with the even more strongly coordinating AlI4− anion the arene coordination is limited to one molecule. Considering mesitylene complexes of gallium, the formation of a mono(arene) complex is unprecedented and even considering group 13 elements in general, the formation of a mono(mesitylene) complex like 3 is unusual. Furthermore, compound 3 is the first structurally characterized arene solvate of a main group metal tetraiodidometallate. [ABSTRACT FROM AUTHOR]

Rhodamine B decorated, mesitylene cored and methylene p‐phenoxy bridged dendrimers 1–3 were synthesized upto second generation in good yield by divergent methodology. The intensity of the UV‐Visible absorption and emission band increases on increasing the number of the dendritic wedges. The antibacterial activity of the dendrimer 3 was found to be better than the lower generation dendrimers 1 and 2 against both the gram positive and gram negative bacteria such as B. subtilis, S. aureus, E. coli and P. aeruginosa. [ABSTRACT FROM AUTHOR]

A polycyclic zwitterion, azoniadibenzo[a,j]phenalenide, having a singlet biradical character, was synthesized and isolated for the first time. The negative charge was found to be delocalized over the periphery of the main core of the zwitterion and the positive charge was localized near the nitrogen atom. Its singlet biradical character was confirmed by a small HOMO–LUMO energy gap with their spatial overlap, and observation of thermally excited triplet species together with DFT calculations. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Mesitylene is employed as the initial material to synthesize the porous carbons. • Mesitylene molecules linked by methylene groups mimic the lignin behaviors closely. • Porous carbons based on mesitylene well performed on selective carbon capture. • Selective carbon capture in carbonaceous micropores is verified by first-principle. Abstract Mesitylene, a representative heavy carbon by-product in the course of C1 chemical downstream processes, is proposed to be employed in this study, as the initial material to synthesize the porous carbons that have played a crucial part in the adsorptive carbon capture process but are generally made from natural carbon resources, instead of fed to the traditional refining process such as hydroprocessing. Based on molecular dynamics calculation, it is proved that once the mesitylene monomers are linked by the flexible methylene groups, the generated polymer can closely mimic the lignin macromolecular behaviors in terms of spatial configuration and atomic thermal motions, which gifts the great potential of the mesitylene-based polymer as applicable a precursor of porous carbon as the biomass-based material. The experimental facts further demonstrate that the porous carbons produced through the routine carbonization of the mesitylene-based polymer can possess desired textural peculiarities, in particular the finely developed micropores that give rise to perfect capacity and selectivity of CO 2 capture, of which underlying mechanism is revealed by the first-principle calculation. The porous carbon generated at 700 °C can reach the CO 2 capture capacity of 6.16 mmol g−1 at 0 °C and 1 bar, which is much higher than many benchmark materials reported, including some biomass-based porous carbons (2.8 mmol g−1, at 0 °C and 1 bar). [ABSTRACT FROM AUTHOR]

A trigonal prismatic Cu6L3 coordination cage has been assembled from Cu(I) and semi‐rigid bipyrazolyl ligand. The X‐ray crystallography demonstrates that the cage has a cavity and can encapsulate the toluene as a guest, exhibiting thermochromism phenomenon. Empty cage can be obtained by expulsion of the guest through single crystal to single crystal transformation. After removed the guest, the empty cage shows a blue‐shifted emission (580 nm), in comparison to its parent cage (615 nm). The empty cage could further serve as a host to encapsulate other aromatic molecules (e. g. mesitylene), which shows new emission band. The trigonal prismatic Cu6L3 coordination cage provides a platform to make advanced luminescent materials. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • ATR dual-comb spectroscopy (DCS) of pure liquids matches a spectral database. • Real-time quantification of liquid-phase chemical reactions using ATR DCS. • This work is an initial step towards evanescent DCS monitoring of micro-reactors. Abstract We combine mid-infrared dual-comb spectroscopy with attenuated total reflectance measurements to provide in-situ monitoring of a chemical reaction. The mid-infrared dual-comb spectrometer measures quantitative absorption cross-sections of mesityl oxide and diacetone alcohol in the region of 3300–2700 cm−1 (3.0–3.7 μm). Based on these spectra, the system is then used to monitor the hydration of mesityl oxide to diacetone alcohol from which we extract reaction kinetics values. This work shows the potential of dual comb systems to measure and monitor reactions in the condensed phase. [ABSTRACT FROM AUTHOR]

Tetrazole- and nitrile-containing bimesitylene derivatives with potential use in coordination chemistry were synthesized and characterized, and their structural particularities are discussed. For the bimesitylene bistetrazole derivative, geometry optimization was carried out by quantum-chemical calculations using density functional theory together with vibrational frequencies, natural bond orbitals, and highest occupied molecular orbital (HOMO)-lowest unoccupied molecular orbital (LUMO) calculations. The newly synthesized bimesitylene derivatives were also evaluated for their antimicrobial activity against three different reference strains, namely Escherichia coli, Staphylococcus aureus, and Candida albicans. [ABSTRACT FROM AUTHOR]

Abstract The MFI zeolites with nanosheet assemblies morphology were prepared by a seed-assisted strategy using specially designed bolaform surfactant [C 6 H 13 -N+(CH 3) 2 -C 6 H 12 -N+(CH 3) 2 -(CH 2) 12 -O-(p-C 6 H 4) 2 -O-(CH 2) 12 -N+(CH 3) 2 -C 6 H 12 -N+(CH 3) 2 -C 6 H 13 ] [Br−] 4 (C 6-12-diphe) as a structure-directing agent. The MFI zeolite nanosheet assemblies were composed of MFI nanosheets with randomly organized structure, exhibiting a narrow mesopore distribution. By tuning the Si/Al ratios of MFI zeolite nanosheet assemblies from 60 to 10, the morphology of resultant zeolites changed from nanosheet stacks to house-of-cards-like structures, and to nanosponges. In addition, the porosity and Brønsted acid/Lewis acid ratio exhibited a parabola-type dependence on the Si/Al ratios of obtained zeolites, indicating that meso-/microporosity and acidity of MFI nanosheet assemblies can be systematically tailored by changing the constituents of zeolites. Catalytic performance of MFI zeolite nanosheet assemblies was investigated in the benzylation of benzyl alcohol with mesitylene. The results revealed that MFI zeolite nanosheet assemblies exhibited extraordinary catalytic activity compared to conventional ZSM-5 zeolite. The conversion of benzyl alcohol and selectivity (1,3,5-trimethyl-2-benzylbenzene vs dibenzyl ether) of zeolite catalysts were linearly dependent on the Brønsted acid/Lewis acid ratio, and they exhibited a parabola-type dependence on the S ext /S BET , indicating that a balance between acidity and porosity of zeolites can be realized to modulate the catalytic properties of MFI zeolite nanosheet assemblies guided by C 6-12-diphe. Graphical abstract Fabrication of 2D MFI zeolite nanosheet assemblies with tailored catalytic activity for benzylation of mesitylene and benzyl alcohol. Image 1 Highlights • MFI zeolite nanosheet assemblies were prepared through seed-assisted approach. • The porosity and acidity of the zeolites can be tailored by tuning the Si/Al ratios. • MFI nanosheet assemblies exhibited enhanced catalytic property due to additional mesoporosity. • The synergy between Brønsted acid and Lewis acid sites was key factor to determine the catalytic activity. [ABSTRACT FROM AUTHOR]

Abstract Organic aromatic cold neutron moderators - like mesitylene (C 9 H 12) - are often much more convenient to handle and to commission than cryogenic methane or ortho/para hydrogen moderators. Although this benefit comes at the cost of reduced brilliance, mesitylene moderators are suited to enable cold neutron applications at sources where a complex traditional cold moderator system is not feasible. Developing the Jülich High Brilliance neutron Source (HBS) project, we have investigated the use of such a low-dimensional mesitylene moderator with MCNP and ANSYS simulations and validated the simulations with experiments at TU Dresden's AKR-2 reactor. Here we will document the feasibility, advantages and drawbacks of such a system and give an outlook on future optimization potentials. [ABSTRACT FROM AUTHOR]

The synthesis of persistent, neutral organic radicals is challenging because of their inherent reactivities. Herein, we report the synthesis and characterization of a highly congested mesityl‐substituted tri(9‐anthryl)methyl (TAntM) radical (1). The scaffold was successfully synthesized by circumventing the steric hindrance imposed by the bulky groups surrounding the central methyl carbon atom. The radical has a threefold propeller structure, and the unpaired electron is mainly localized on the central carbon atom. Owing to its congested structure, 1 is remarkably stable, which facilitated handling under ambient conditions. Evaluation of the dynamic behavior of the TAntM scaffold indicated that the stability is due to the bulky anthryl units and the mesityl substituents. Because of its high persistence, wide‐range absorption, and good reversible redox properties, 1 has promising applications in organic devices. A highly congested tri(9‐anthryl)methyl radical was successfully synthesized by circumventing the steric hindrance imposed by the bulky groups surrounding the central methyl carbon atom. Owing to its congested structure, the mesityl‐substituted tri(9‐anthryl)methyl radical is remarkably stable, which facilitates its handling under ambient conditions. [ABSTRACT FROM AUTHOR]

Femtosecond laser studies have been performed to investigate the initial photodissociation reactions of I2–mesitylene charge transfer complexes. Photodissociation occurs along both the I2–mesitylene ‘‘bond’’ and the I–I bond with a branching ratio of 2:3 for the two reaction coordinates. Following excitation at 400 nm, geminate recombination occurs along both reaction coordinates. The reformed I2–mesitylene complexes are formed vibrationally hot and relax on a time scale of 13 ps. The I–mesitylene spectrum is fully developed within 500 fs of the pump pulse. Approximately 40% of the I–mesitylene complexes undergo geminate recombination on a time scale of 14 ps. Most of the remaining complexes recombine with their original partners on a time scale of 400 ps. The initial anisotropy of the photoproduct absorption is 0.09±0.02. This low anisotropy is a direct result of the geometry of the complex and nature of the electronic transition rather than indicative of ultrafast motion toward an asymmetric transition state preceding dissociation. © 1995 American Institute of Physics. [ABSTRACT FROM AUTHOR]

Examines the vibrational relaxation of iodine in the complexing solvent mesitylene. Application of transient absorption measurements; Characterization of the energy relaxation; Influence of iodine vibrational relaxation on intramolecular vibrational energy redistribution process.