Catalysis

During translation, tRNAs must move rapidly to their adjacent sites in the ribosome while maintaining precise pairing with mRNA. This movement (translocation) occurs in a stepwise manner with hybrid-state intermediates, but it is unclear how these hybrid states relate to kinetically defined events of translocation. Here we analyze mutations at position 2394 of 23S rRNA in a pre-steady-state kinetic analysis of translocation. These mutations target the 50S E site and are predicted to inhibit P/E state formation. Each mutation decreases growth rate, the maximal rate of translocation ( k trans ), and the apparent affinity of EF-G for the pretranslocation complex (i.e., increases K 1/2 ). The magnitude of these defects follows the trend A > G > U. Because the C2394A mutation did not decrease the rate of single-turnover GTP hydrolysis, the >20-fold increase in K 1/2 conferred by C2394A can be attributed to neither the initial binding of EF-G nor the subsequent GTP hydrolysis ste...

EF4, though similar structurally to the translocase EF-G, promotes back translocation of tRNAs on the ribosome, and is important for bacterial growth under certain conditions. Here, using a coordinated set of in vitro kinetic measures, including changes in the puromycin reactivity of peptidyl tRNA and in the fluorescence of labeled tRNAs and mRNA, we elucidate the kinetic mechanism of EF4-catalyzed back translocation and determine the effects of the translocation inhibitors spectinomycin and viomycin on the process. EF4-dependent back translocation proceeds from post-translocation complex (POST) to pre-translocation complex (PRE) via a four-step kinetic scheme, i.e., POST → I 1 → I 2 → I 3 → PRE, that is not the simple reverse of translocation. During back translocation, movements of the tRNA core regions and of mRNA are closely coupled to one another, but are sometimes decoupled from movement of the 3′-end of peptidyl-tRNA. EF4 may be thought of as performing an interrupted catalysis of back translocation, stopping at the formation of I 3 rather than catalyzing the complete process of back translocation culminating in PRE complex formation. The delay in polypeptide elongation resulting from transient accumulation of I 3 is likely to be important for optimizing functional protein biosynthesis.

Figure 1. Lab scale pulsed-flow experimental setup showing the horizontal quartz reactor system (upper left) coupled to a molecular beam mass spectrometer (MBMS, right) for realtime analysis of products. Catalyst is shown pre-and postreaction (coked).

Carboxylic acids such as acetic acid and propionic acid have been investigated as representative components for fast pyrolysis (FP) bio-oil upgrading. Selective catalytic conversion of carboxylic acids can enhance bio-refinery processing economics through catalyst preservation and process intensification. Various metal-doped molybdenum carbide bead catalysts have been synthesized and developed in this work.  Our aim is to enable selective conversion of carboxylic acids. In the case of acetic acid conversion, calcium doped Mo2C beads offer the highest yield of acetone ~96% at 450 °C among undoped and Ca or Ni doped catalysts. By comparing hot gas filter with and without Ca-Mo2C catalyst tested with real FP vapors, the former showed a 36.7% reduction of acetic acid, a 37.5% reduction of small ketones in aqueous phase, and a ~50% reduction of methoxies (methoxy phenols and methoxy aromatics) in organic phase. The conversion resulted in the formation of more long chain chemical...

New Synthesis of Benzothiazines and Benzoisothiazoles Containing a Sulfoximine Functional Group. -A successful initial exploration via the reaction of sulfoxime (I) with a variety of the terminal alkynes is presented. The reaction affords predominantly thiazines with alkylalkynes, while thiazoles are favored in the cases of arylalkynes.

Se prepararon sólidos micro/mesoporosos del tipo MOR/MCM-41, con diferentes relaciones Si/Al. Para esto se colocó 3,15g de zeolita en solución de NaOH 3M y se agitó la suspensión por 30 min. Luego se agregaron 40 g de una solución de bromuro de hexadeciltrimetil-amonio (CTAB al 16% p/p) y se agitó por 30 minutos nuevamente. La mezcla fue depositada en un reactor de acero revestido de teflón y tratada hidrotérmicamente a 373 K por 24 h. Después de esto, el pH fue ajustado a 8,5. La mezcla fue depositada nuevamente en el reactor por 24 h más a 373 K. El producto sólido fue recuperado por filtración y se lavó con etanol y agua desionizada, para posteriormente secarlo en aire a 353 K y luego calcinarlo 6 h a 823 K. La forma ácida de estos sólidos fue obtenida mediante intercambio iónico en solución de NH NO 1 M a 343 K. Esos compuestos fueron caracterizados por MEB, EDX, DRX, TGA 4 3 y adsorción de N . Los sólidos obtenidos presentan áreas superficiales y volúmenes de poro

Crystals of the catalytic subunit of Methanococcus jannaschii aspartate transcarbamoylase in an orthorhombic crystal form contain four crystallographically independent trimers which associate in pairs to form stable staggered complexes that are similar to each other and to a previously determined monoclinic C2 form. Each subunit has a sulfate in the central channel. The catalytic subunits in these complexes show flexibility, with the elbow angles of the monomers differing by up to 7.4 between crystal forms. Moreover, there is also flexibility in the relative orientation of the trimers around their threefold axis in the complexes, with a difference of 4 between crystal forms.

Cerium-manganese mixed oxides with different composition were prepared by co-precipitation, characterized and evaluated for the water-gas shift (WGS) reaction. Base metal (5 wt.% Cu and 5 wt.% Ni) catalysts supported on Ce-Mn mixed oxides were also tested for the WGS reaction. The activity of the bare supports is higher in the mixed samples than in pure ceria or manganese oxide. This result can be explained by a combination of greater reducibility and surface area in the mixed samples. Addition of base metals produces superior WGS catalysts. Particularly, nickel catalysts tested are able to reduce typical CO concentrations entering the WGS process to the CO levels tolerated by phosphoric acid fuel cells in a single unit operated at 400 °C.

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RuII‐catalyzed intermolecular double [2+2+2] cycloadditions of 1,6‐diynes and alkynylthiocyanates have been developed for the synthesis of 2‐aryl thiopyridines. Aryl thiocyanates were isolated chemoselectively as a result of initial intermolecular [2+2+2] cycloaddition product. The method offers operational simplicity and is atom economical in nature.

An efficient method to access 2-triazolyl thio-/selenopyridines with good to excellent yields by ruthenium(II)-catalyzed one-pot [3 + 2]/[2 + 2 + 2] cycloaddition reactions of azides, 1-alkynyl thio-/ selenocyanates and 1,6-diynes is reported. This atom-economical catalytic strategy offers a mild and practical approach to access a variety of such cycloadducts with good to excellect regioselectivities. The protocol was further extended to the synthesis of 3,3'-bis(triazolyl thio-/seleno)-2,2'-bipyridines by the reaction of tetraynes with 1-alkynyl thio-/selenocyanates in the presence of aryl/alkyl azides.

Catalytic activity/Alcohol decomposition/Lanthanide oxides/ Compensation effect The decomposition of 1-propanol and 2-propanol over a series of eight lanthanide oxides (La203, Ce02, Pr60, (, Sm203, Eu203, Dy203, Ho203 and Yb203) is studied. The activity data were obtained in a flow reactor at normal pressure. The alcohol partial pressure was around 69KPa (520Torr). The conversions were generally lower than 10%. Dehydrogenation to carbonylic products and dehydration to propylene were the only reactions here observed. For both alcohols, the differences of activity among the eight oxides, though significant, were within one order of magnitude. Contrary to suggested in the literature no simple relationship was found between the position of 4/element in the series and the catalytic activity of the corresponding oxides. No definite patterns of apparent activation energies or selectivity data were observed either. When the reactivities of 1-propanol and 2-propanol towards dehydration are compared, significantly lower values are found for the former alcohol. The origin of this influence of the alcohol structure, as well as the chemical meaning of the observed linear relationships between E" and log .4, are discussed.

< A high oxidation current in glycerol electro-oxidation was observed at 250 C. < High selectivity for CO 2 production was obtained at 250 C. < CeC bond dissociation ratio reached 70e80% at both low and high potentials. < Stable operation during glycerol electro-oxidation at around 250 C requires a high S/C ratio. < The present observations provide strategies for the effective operation of DAFCs.

Yeni, suda &ccedil;&ouml;z&uuml;nen 2(3),9(10),16(17),23(24)-tetrakis [4-(1-naftoksi-4-sulfonik asit sodyum)] kobalt(II)ftalosiyanin, NhtCoPc (Nht burada 1-naftoksi-4-sulfonik asit sodyum tuzu), sentezlendi, elementel analiz y&ouml;ntemi, spektroskopik y&ouml;ntemlerle (IR ve UV&ndash;vis) karakterize edilerek ve elektro-kimyasal, spektroelektrokimyasal ve molek&uuml;ler oksijenin indirgenmesine y&ouml;nelik elektro-katalitik davranışları detaylı bir şekilde incelendi. Kompleksleşme reaksiyonu metanol ortamında 2(3),9(10),16(17),23(24)- tetrakis [4-(1-naftoksi-4-sulfonik asit sodyum)] ftalosiyanin, NhtH2Pc&rsquo;nin UV-vis spektrum değişikliklerine g&ouml;re takip edildi. Q bandının maksimum şiddette olduğu anda reaksiyon tamamlandı. Elektrokimyasal &ccedil;alışmalardan şu sonu&ccedil;lar &ccedil;ıkarılmıştır: DMSO &ccedil;&ouml;zeltisinde kobalt(II) kompleksi anodik dalgaya karşılık gelen bir elektronlu iki tersinir indirgenme reaksiyonu ve bir tersinir olmayan y&uuml;kseltgenme re...

In the present study, a single stage sodium borohydride (SBH) synthesis process from anhydrous borax without the use of sodium metal was developed. The effects of process parameters namely temperature, reaction time and hydrogen pressure on the efficiency of SBH production were investigated in an autoclave type fixed bed reactor (V ¼ 1000 cm 3 ). The optimum range of operating conditions was T ¼ 550e560 C, P H2 ¼ 40 À 50 bar and t ¼ 4e6 h. Under these conditions, the production efficiency of SBH was 85e90% by mole and purity was determined as 97e99%. It was observed that SBH efficiency was highly influenced by synthesis conditions while its purity was not. For the hydrolysis of SBH, different effective heterogeneous catalysts were prepared. Hydrolysis tests have been performed at ambient temperature over a range of sodium hydroxide concentration (2.5e15 wt%) and sodium borohydride concentration (5e40 wt%) in the presence of a selected Ni(20%)eFe(20%)/g-Al 2 O 3 catalyst. The basic principles for SBH hydrolysis were also outlined for PEM fuel cell applications.

Pc'nin UV-vis spektrum değişikliklerine göre takip edildi. Q bandının maksimum şiddette olduğu anda reaksiyon tamamlandı. Elektrokimyasal çalışmalardan şu sonuçlar çıkarılmıştır: DMSO çözeltisinde kobalt(II) kompleksi anodik dalgaya karşılık gelen bir elektronlu iki tersinir indirgenme reaksiyonu ve bir tersinir olmayan yükseltgenme reaksiyonu sergilemiştir. Gerçekleşen indirgenme reaksiyonları ve yükseltgenme reaksiyonu, Co(1+)Pc( Pt/PAni-NhtCoPc elektrot hazırlandı. Modifiye edilmiş elektrot SEM (elektron mikroskopu ile) karakterize edildi. NhtCoPc'ninpolimerizas-yon ortamına ilavesi ile elde edilen filmin morfolojisi önemli ölçüde değiştiği ve oluşan PAni-NhtCoPc filmin oksijen indirgenmesine yönelik redoks aktivitesinin yalnız platin ya da Pt/PAni elektrodlara kıyasla aynı deney koşullarında arttığı görüldü.

Lanthanum perovskites were synthesized by malic acid complexation and different amounts of palladium were added by dry-wet impregnation. Measurements of methane conversion on fresh and SO 2 -treated perovskite catalysts were made between 25 and 500 • C. Methane conversion on fresh catalysts commenced at ∼300 • C, and the best activities were achieved with low loadings of palladium. The B-site metal combinations Mn 0.4 Fe 0.6 and Mn 0.6 Fe 0.4 showed better conversion activity than Mn 0.5 Fe 0.5 and Fe. All fresh perovskite catalysts except those with 10% Pd gave 100% conversion of methane at 500 • C. The resistance of 10% Pd perovskite catalysts to sulfur was generally better than that of catalysts with low Pd loadings. This was due to the high Pd coverage on the perovskite surface. Fresh and SO 2 -treated LaMn 0.4 Fe 0.6 O 3 perovskite catalysts promoted with 2 and 2.5% of palladium exhibited the highest activities for methane conversion.

Two types of catalytic washcoats with different properties can be present simultaneously in a monolith channel, e.g. the flat foils and the corrugated ones in metallic monolith can be individually coated with specific type of the washcoat. The model of such multiphase, differentiated NO x storage and reduction (NSR) catalytic monolith converter has been developed. The important reactions as are the oxidation of carbon monoxide, hydrocarbons and hydrogen, the reduction of nitrogen oxides (NO x ), the water gas shift and the steam reforming reactions, the NO/NO 2 transformation, and the oxygen and NO x storage are considered. Unknown kinetic parameters of the NSR are evaluated from transient experiments with the samples of two different types of NSR catalysts. The first catalyst is of the Pt-␥-Al 2 O 3 -CeO 2 type with alkali earth metals (e.g. barium) as NO x storage components (active at lower temperature). The second one is of the PtRh-␥-Al 2 O 3 -CeO 2 type with both alkali earth metals and alkali metals (e.g. potassium) as NO x storage components (active at higher temperature). Simulations of periodic lean/rich operation of the low-temperature, the high-temperature and the differentiated (combined) NSR converters are performed. The results of the computations agree well with the experimental data. The dependences of integral NO x conversion on the lengths of the lean and rich phases and on the temperature of the inlet gas are discussed. The efficiencies of the low-temperature, the high-temperature and the differentiated NSR converters are compared at different operating conditions.

The durability of four noble metal catalysts was investigated in solvent emission oxidation. Mono-and bimetallic catalysts (Pt, Pt-Pd) were supported on ␥-Al 2 O 3 -La or ␥-Al 2 O 3 -Ce washcoats and they were aged in industrial conditions for max. 25 months. The catalytic activities (lightoff experiments with methane and n-butyl acetate) were determined before and after the ageing to compare the behaviour of catalysts. Catalysts were also characterized by BET and chemisorption measurements as well as with XRD, FTIR and SEM. According to the results, all the catalysts showed excellent stability after the ageing periods and no significant reduction in the activities were observed in the oxidation of n-butyl acetate. However, a small reduction in the activity of the catalysts was observed in the case of methane oxidation, which is related rather to poisoning or fouling of the catalysts than to thermal deactivation. This observation was also supported by other catalyst characterization methods.

The kinetics of CO oxidation and NO reduction reactions over alumina and alumina-ceria supported Pt, Rh and bimetallic Pt/Rh catalysts coated on metallic monoliths were investigated using the step response technique at atmospheric pressure and at temperatures 30-350°C. The feed step change experiments from an inert flow to a flow of a reagent (O,, CO, NO and Hz) showed that the ceria promoted catalysts had higher adsorption capacities, higher reaction rates and promoting effects by preventing the inhibitory effects of reactants, than the alumina supported noble metal catalysts. The effect of ceria was explained with adsorbate spillover from the noble metal sites to ceria. The step change experiments CO/O, and O/CO also revealed the enhancing effect of ceria. The step change experiments NO/H, and Hz/NO gave nitrogen as a main reduction product and N,O as a by-product. Preadsorption of NO on the catalyst surface decreased the catalyst activity in the reduction of NO with H,. The CO oxidation transients were modeled with a mechanism which consisted of CO and 0, adsorption and a surface reaction step. The NO reduction experiments with H, revealed the role of N,O as a surface intermediate in the formation of N,. The formation of N-N bonding was assumed to take place prior to, partly prior to or totally following to the N-O bond breakage. High NO coverage favors N,O formation. Pt was shown to be more efficient than Rh for NO reduction by H,.

A new series of 14–16-membered hexaazamacrocyclic complexes [ML1X2] and [ML2X2] (M = CoII, NiII, CuII and ZnII; X = Cl or NO3) have been synthesized by template condensation of phenylenediamine, primary diamines and formaldehyde solution 35% in MeOH and have been characterized by i.r., 1H-n.m.r., e.p.r., and u.v. spectroscopy as well as by magnetic susceptibility and conductivity measurements. An octahedral

The earlier work carried out in our laboratory led to the identification of a novel rat liver microsomal enzyme termed as acetoxy drug: protein transacetylase (TAase), catalyzing the transfer of acetyl group from polyphenolic acetates (PA) to functional proteins. In this paper, we have reported the comparison of the specificities of acetoxy derivatives of coumarins, biscoumarins, chromones, flavones, isoflavones and xanthones with special reference to the phenyl moiety/bulky group on the pyran ring of PA. The results clearly indicated that compounds having phenyl moieties, when used as the substrates, resulted in a significant reduction of TAase catalyzed activity. The alteration in TAase catalyzed activation of NADPH cytochrome c reductase and inhibition of benzene-induced micronuclei in bone marrow cells by PA were in tune with their specificities to TAase.

Palladium-catalysed aminocarbonylation of iodobenzene and 1-iodocyclohexene with both enantiomerically pure and racemic 2,2'-diamino-1,1'-binaphthalene (BINAM) as N-nucleophile was carried out. The mono-and dicarboxamide enantiomers possessing axial chirality were synthesised using (S ax )-BINAM. In the possession of these reference compounds the partial chiral kinetic resolution of racemic BINAM was carried out using various optically active bidentate ligands such as (2S,4S)-BDPP, (2S,3S)-CHIRAPHOS and (R)-BINAP. It was revealed by chiral HPLC measurements that up to 10 % enantiomeric excess of carboxamides can be achieved in this way. Although with low enantioselection, enantioselectve aminocarbonylation was carried out for the first time.

Para-substituted iodobenzenes were reacted with tert-butyl isocyanide and piperidine as nucleophiles in the presence of palladium-diphosphine catalysts. Both single and double insertion of the isocyanide was observed and the corresponding amidines and ketimine-amidines were obtained in yields of practical interest. With the increase of the tert-butyl isocyanide/iodobenzene ratio, 100% chemoselectivity toward the ketimine-amidine was achieved. The formation of the products was rationalized on the basis of a catalytic cycle analogous to that of the aminocarbonylation reactions. Clear connection was found between the activity and the electronic structure of the proposed catalyst Pd(diphosphine) by computational studies, as the more negative partial charge on palladium resulted in higher conversion. Among five isocyanide substrates, only tert-butyl isocyanide was proved to be active.

Poly-ADP-ribose polymerases (PARPs1-16) play pivotal roles in diverse cellular processes. PARPs that catalyze poly-ADP-ribosylation (PARylation) are the best characterized PARP family members because of the availability of potent and selective inhibitors for these PARPs. There has been comparatively little success in developing selective small-molecule inhibitors of PARPs that catalyze mono-ADP-ribosylation (MARylation), limiting our understanding of the cellular role of MARylation. Here we describe the structure-guided design of inhibitors of PARPs that catalyze MARylation. The most selective analog, ITK7, potently inhibits the MARylation activity of PARP11, a nuclear envelope-localized PARP. ITK7 is greater than 200-fold selective over other PARP family members. Using live-cell imaging, we show that ITK7 causes PARP11 to dissociate from the nuclear envelope. These results suggest that the cellular localization of PARP11 is regulated by its catalytic activity.

The dehydroisomerization of n-butane to isobutene over Pt/metal/sulphated zirconia catalysts was studied at 550 • C and 1 Atm. Sulfated zirconia catalysts (SZ), promoted with Al, Mn, Cu and Ni, were synthesized by coprecipitation. The catalysts were characterized by AAS, ICP-MS, TGA, and XRD. Effects of metals, sulfur content, and crystallite size of the samples on the selectivity and yield to isobutene were investigated. The increase in crystallite size and sulfur content caused an increase in the selectivity of total butenes. The presence of platinum and second metal improved the catalytic stability and isomerization selectivity of SZ catalyst for n-butane isomerization. SZ catalyst with aluminum showed much higher selectivity towards isobutene than the unpromoted ones.

Electrochemical CO 2 reduction reaction (CO 2 RR) holds a great potential for converting CO 2 into valuable carbon-based chemicals and fuels. A promising strategy for enhancing CO 2 RR performance is the deliberate structural design of electrocatalysts, which can maximize the utilization of inherent structural advantages. In this work, SnO 2 nanocubes (NCs) and nanorods (NRs) are synthesized using a surface energy-driven growth orientation method, where the stable (110) facet and the highly energetic (001) facet constitute the SnO 2 nanostructures. Leveraging the inherent structural merits of different facets on SnO 2 , theoretical calculations reveal that the (001) facet plays a primary role in inhibiting hydrogen evolution reaction (HER), while both (110) and (001) facets are highly favorable for CO 2-to-formate conversion under the external bias. As a result, SnO 2 NCs with a higher facet ratio of (001)/(110) achieve nearly 100% selectivity for the formation of carbonaceous products during CO 2 RR. More importantly, a maximum partial current density of about 1 A cm-2 with a formate Faradaic efficiency (FE) of over 90% is achieved in a flow cell, distinguishing it from most of the reported Sn-based electrocatalysts. These results highlight the strategic advantages of leveraging the inherent structure of nanomaterials for efficient CO 2 RR. 1. Introduction The electrochemical reduction of CO 2 (CO 2 RR) is being considered as a viable alternative to address the recent increase in CO 2

Hydrogen and oxygen evolution from MgO prepared by thermal decomposition of high purity Mg(OH)2 was studied mass spectroscopically. Hydrogen is evolved in the temperature range 300-600°C (maximum at 450%) and again between 600 and 900°C (maximum at 750°C). The amount of Hz evolved is of the order of 1010-1020 molecules g-l MgO. An equivalent amount of oxygen appears to be evolved predominantly as atomic oxygen between 600 and 9OOW. The first Hz evolution is assigned to the formation of Hz molecules within cation vacancies [Mg]" in the MgO neighbored by two OH-groups, leading to the formation of Oions: 2 OH-e2 O-+ Hz. The second Hz evolution is assigned to the dissociation of residual OH-groups: OH--+ O-+ fH2. Th e oxygen evolution is probably due to decomposition of O-: 20--+ 02-+ 0. The O-concentration in the MgO calculated on the basis of these experiments is lo'-106 times higher than the concentration of VI centers achieved by thermal activation and measured bv esr. This indicates that only a very small fraction of the O-ions present in the sample is able to form VI centers.

The specific volume is obtained from the lever rule with X L D 0:25: 0:25/.1:269/ C .1 0:25/.44:037/ D 33:345 cm 3 /g a) We know P D 80 bar, V D 33:345 cm 3 /g. From the steam tables we find: T D 375 ı C; V D 32:222 cm 3 /g T D 400 ı C; V D 34:31 cm 3 /g By interpolation at V D 33:345 cm 3 /g we obtain T D 388:5 ı C. b) From saturated tables we find:

This book is the product of some 20 years of teaching thermodynamics at Penn State, but it would not have happened without the help, direct or indirect, of several individuals, colleagues, students, and friends. I must start by thanking Andrew Zydney, my colleague and department head, who encouraged me to spend my 2010-2011 sabbatical finishing this textbook. Without Andrew's nudging, the book would have remained in the perpetual state of a draft-in-progress. I want to thank my colleagues, Darrell Velegol, Scott Milner, Seong Kim, Rob Rioux, and Enrique Gomez, who trusted drafts of the book, in various stages of completion, for use in their classes. Among those who reviewed the near-final draft, I want to thank Michael M. Domach and Tracy J. Benson, who offered comments that were especially insightful and encouraging. The number of students, whose feedback over the years shaped this book, is too large to list. But special thanks must go to my Fall 2011 class of CH E 220H, the honors section of Thermo I, on whom fell the unenviable task of debugging the first finished version of this book. They did this admirably. Of all the students in that class special mention goes to Steph Nitopi, Twafik Miral, Brian Brady, and Ashlee Smith, whose attention to detail was nothing but extraordinary. Bernard Goodwin and Michelle Housley of Pearson Education guided me through this book project-my first one-with a light hand and flexible deadlines. I want to thank Elizabeth Ryan, John Fuller, and Michelle Gardner, who, as members of the production team, brought my vision of this book to life. My wife Kristen, and daughter Melina, helped in many ways, big and small, in carrying this project out. And lastly, I feel grateful to LuLu, our little dog, who sat approvingly on my armchair next to me through countless hours of typing.

Graphene oxide (GO) has layered structure with carbon atoms that are highly coated with oxygencontaining groups, increasing the interlayer distance while simultaneously making hydrophilic atomic-thick layers. It is exfoliated sheets that only have one or a few layers of carbon atoms. In our work, Strontium Ferrite Graphene Composite (SF@GOC) has been synthesized and thoroughly characterized by physico-chemical methods like XRD, FTIR, SEM-EDX, TEM, AFM, TGA and Nitrogen adsorption desorption analysis. A very few catalysts have been manufactured so far that are capable of degrading Eosin-Y and Orange (II) dyes in water by heterogeneous catalytic method. The current study offers an overview of the recyclable nanocomposite SF@GOC used in mild reaction conditions to breakdown the hazardous water pollutant dyes Eosin-Y (96.2%) and Orange (II) (98.7%). The leaching experiment has demonstrated that the use of the transition metals strontium and iron have not result in any secondary contamination. Moreover, antibacterial and antifungal assay have been investigated. SF@GOC has shown greater activity with bacterial and fungal species while compared with GO. FESEM analysis shows that the bactericidal mechanism for SF@GOC is same in both gram-negative bacteria. The difference in the antifungal activity among the candida strains can be correlated with the movement of ions release (slower and faster) of synthesized nanoscrolls in SF@GOC. In comparison to previous reports, this new environmentally safe and novel catalyst showed substantial degrading activity. It can also be applied to new multifunctional processes such as in the fields of composite materials, solar energy, heterogeneous catalysis and biomedical applications. The textile industry uses dyes extensively. The wastewaters from these industries cause significant water pollution. Dyes in wastewater modifies chemically, scavenge dissolved oxygen and terminate aquatic life. Additionally, some dyes and their degradation products may be carcinogenic and/or toxic. So, the wastewaters from the textile industries should be treated before their discharge into environment. The aquatic ecology has been destroyed as a result of the effluent from the dyeing businesses, which contain dangerous and cancer-causing pigments that are harmful to fish, aquatic microbes and animals as well as cause major risks to the ability of photosynthesis for aquatic plants 1 . Treatment of such organic stains in water with small amounts of pollution has long drawn the interest of numerous researchers. The accessible traditional techniques for getting rid of this kind of colour are not suitable for the requirements for current water sources and water quality. Eosin-Y, a red fluorescent dye from the xanthene family, has often been used in a number of applications, including as a biological stain, laser dye, fluorescent study, nanocomposite production process and polymerization process. Since Eosin-Y has benzene and pyran rings as well as a carboxyl group, it can be carcinogenic when used extensively in sensitizing industries, biomedical research labs and for diagnostic purposes. Due to its toxicity, Eosin-Y and Orange (II) create problems with the environment by being directly discharged into waste water 1-3 . The synthetic dyes known as azo dyes are difficult to break down and the byproducts are exceedingly poisonous. Dye-based products and the textile sector are dangerous sources of air pollution. These include one or more azo bonds (-N=N-) acting as chromophore groups in conjunction with aromatic structures that have functional groups like -OH and -SO 3 H 4 . Additionally, it is one of the most contaminated synthetic dyes. Wu et al. carried out synthesis of iron

Graphene oxide (GO) has layered structure with carbon atoms that are highly coated with oxygen-containing groups, increasing the interlayer distance while simultaneously making hydrophilic atomic-thick layers. It is exfoliated sheets that only have one or a few layers of carbon atoms. In our work, Strontium Ferrite Graphene Composite (SF@GOC) has been synthesized and thoroughly characterized by physico-chemical methods like XRD, FTIR, SEM–EDX, TEM, AFM, TGA and Nitrogen adsorption desorption analysis. A very few catalysts have been manufactured so far that are capable of degrading Eosin-Y and Orange (II) dyes in water by heterogeneous catalytic method. The current study offers an overview of the recyclable nanocomposite SF@GOC used in mild reaction conditions to breakdown the hazardous water pollutant dyes Eosin-Y (96.2%) and Orange (II) (98.7%). The leaching experiment has demonstrated that the use of the transition metals strontium and iron have not result in any secondary contami...

Toxic and bio-resistant phenolic compounds are some of the most common hazardous organics in aqueous systems presenting challenging problem in waste water treatment. In the present study, wet oxidation without a chemical oxidant was attempted using Mn(II)@silica as the catalyst. The catalysts were well characterized by physico-chemical characterization methods. The conversion of phenol, 2-chlorophenol and 2-nitrophenol was 89.7, 85.5 and 78.8 % with hydrothermally synthesized Mn(II)@silica, and 94.2, 91.1 and 89.4 % with impregnated Mn(II)@silica, respectively. The reactions followed pseudo first order kinetics. The effects of pH, reaction time, catalyst load, feed concentration, and temperature were investigated. GC-MS analysis showed that the persistent organics were oxidized to simpler end products. Further oxidation is expected lead to complete mineralization of the contaminants. Mn(II) coupled silica was noticed to be a better oxidation catalyst for the organic pollutants than ...

This study explored Fischer–Tropsch synthesis (FTS) by combining a non-thermal plasma (NTP), generated by an arc discharge reactor at pressures &gt;&gt; 1 MPa, coupled with a mullite-coated 2 wt%-Co/5 wt%-Al2O3 catalyst. The FTS product yields and electrical energy consumption for the pure plasma (no catalyst) and plasma-catalytic FTS processes were compared under the scope of various reactor operating parameters, namely, pressure (0.5 to 10 MPa), current (250 to 450 mA) and inter-electrode gap (0.5 to 2 mm). The major products, obtained in low concentrations for both processes, were gaseous C1–C3 hydrocarbons, synthesised in the order: methane &gt;&gt; ethane &gt; ethylene &gt; propane. The hydrocarbon product yields were observed to increase, while the specific required energy generally decreased with increasing pressure, decreasing current and increasing inter-electrode gap. Plasma-catalysis improved the FTS performance, with the optimum conditions as: (i) 10 MPa at 10 s and 2 MP...

The influence of different catalyst cobalt loadings on the C1–C3 hydrocarbon product yields and energy consumption in plasma-catalytic Fischer-Tropsch synthesis (FTS) was investigated from the standpoint of various reactor operating conditions: pressure (0.5 to 10 MPa), current (250 to 450 mA) and inter-electrode gap (0.5 to 2 mm). This was accomplished by introducing a mullite substrate, coated with 2 wt%-Co/5 wt%-Al2O3, 6 wt%-Co/5 wt%-Al2O3 or 0 wt%-Co/5 wt%-Al2O3 (blank catalyst), into a recently developed high pressure arc discharge reactor. The blank catalyst was ineffective in synthesizing hydrocarbons. Between the blank catalyst, 2 wt%, and the 6 wt% Co catalyst, the 6 wt% improved C1–C3 hydrocarbon production at all conditions, with higher yields and relatively lower energy consumption at (i) 10 MPa at 10 s, and 2 MPa at 60 s, for the pressure variation study; (ii) 250 mA for the current variation study; and (iii) 2 mm for the inter-electrode gap variation study. The inter-e...

Hydrogen peroxide synthesis from hydrogen and oxygen in the gas phase is postulated to be a key reaction step in the gas phase epoxidation of propene using gold-titanium silicate catalysts. During this process H 2 O 2 is consumed in a secondary step to oxidise an organic molecule so is typically not observed as a reaction product. We demonstrate that using AuPd nanoparticles, which are known to have high H 2 O 2 synthesis rates in the liquid phase, it is possible to not only oxidise organic molecules in the gas phase but to detect H 2 O 2 for the first time as a reaction product in both a fixed bed reactor and a pulsed Temporal Analysis of Products (TAP) reactor without stabilisers present in the gas feed. This observation opens up possibility of synthesising H 2 O 2 directly using a gas phase reaction.