Past research has examined the many ways individuals behave in response to unconscious primes. For instance, unconsciously activating stereotypes leads people to exhibit behavior that parallels the target stereotype (e.g., Bargh, Chen, & Burrows, 1996; Dijksterhuis & van Knippenberg, 1998). Priming methodology has also been extended to inducing mortality salience, such that specific behaviors emerge in response to thinking about one’s own death. Two theories, socioemotional selectivity theory and terror management theory, hypothesize how individuals cope with thoughts about the end of life. The present study attempted to extend past research by comparing older and younger adults’ responses to unconscious mortality salience. Fifty-nine younger adults and 52 older adults were randomly assigned to one of two prime conditions: death prime or negative prime. The unconscious primes were administered through word searches, which contained 20 target words related to each prime. Defenses to the primes were assessed via suitability ratings and reaction times to a picture-caption task, which contained both neutral and emotional (positive and negative) captions paired with neutral pictures. A defense was operationalized as higher suitability ratings and faster reaction times to the positive captions, as well as lower suitability ratings and slower reaction times to the negative captions. Based on terror management theory, it was expected that individuals who were primed with death would display specific defensive behavioral responses as compared to those who were primed with negativity, regardless of age. Socioemotional selectivity theory, however, predicts that these defenses may also emerge when older adults are primed with negativity due to the increased tendency for older adults, relative to younger adults, to automatically implement default emotion regulatory goals. Analyses revealed that both younger and older adults embraced the neutral and positive captions after being primed with death. Participants primed with negativity were also more likely to embrace positivity. Age differences emerged such that younger adults were faster when reacting to emotional captions in the death condition than in the negative condition. Conversely, older adults primed with negativity reacted faster to emotional captions than those primed with death. Implications for terror management theory and socioemotional selectivity theory are discussed. Overall, both young and older adults displayed defenses to prime-activated threats of death and negativity. The implementation of death-related defenses was stronger for younger adults than the implementation of negativity-related defenses, but the opposite was true for older adults.

The inhibiting and deactivating effects of basic nitrogen species present in gas oils on catalyst active sites has been well recognized over the years; however, recent studies have shown comparable inhibiting and deactivating effects exhibited by non-basic nitrogen species. A novel pre-treatment technique employing the heterogeneously cross-linked macroporous polymer poly(glycidyl methacrylate) (PGMA) as the hydrophilic support coupled with organic compound tetranitrofluorenone has shown promising results for the selective elimination of non-basic nitrogen heterocyclic species from bitumen derived heavy gas oil (HGO). Characterization techniques such as Scanning electron microscopy (SEM), low temperature N2 adsorption–desorption (BET), CHNOS elemental analysis, fourier transform infrared spectroscopy (FT-IR), epoxy content titration, and thermo gravimetry/differential thermal analyzer (TG/DTA) were employed for determining the optimum parameters during each step of the polymer synthesis. Step 1 comprised of direct polymerization of the monomers under the determined optimum conditions, with specific surface area of 34.7 m2/g and epoxy content of 5.8 wt% for the PGMA polymer support. Step 2 comprised of substitution of the epoxy ring with the acetone oxime functionality; FT-IR results indicated characteristics peaks at 1650 cm-1 which ascertained the presence of acetone oxime on the polymer, with epoxy content titration indicating a decrease of up to 33% of the epoxy content due to the substitution. Coupling of the organic compound tetranitrofluorenone with the polymer was performed in the final step, with TGA and DTG results indicating highest weight loss of approximately 126.9 μg, which signified that sample T had the greatest amount of organic compound present in comparison to the other samples (sample N to Sample S). The optimized polymer (sample T) was capable of removing nitrogen up to 6.7%, while having little to no influence on the sulphur or aromatic species. These results were in agreement with step 4 TGA analysis that showed sample T had the highest presence of the organic compound. Reusability of the polymer multiple times with consistent removal is another known advantage of such a pre-treatment technique; hence reusability studies were performed, and showed that the polymer was indeed capable of multiple uses, with consistent removal of nitrogen compounds at approximately 6.5% from fresh heavy gas oil feedstocks. Kinetic studies were performed as the final phase in order to evaluate the performance of the treated HGO in comparison to non-treated HGO. The effect of parameters such as temperature and LHSV were determined, with higher temperatures resulting in higher conversion of HDS and HDN. Similarly, as the LHSV was decreased, the conversions were increased for both HDS and HDN due to longer contact time between the feed and the catalyst. The highest obtained conversions were at an LHSV of 0.5 hr-1 and temperature of 395°C with treated HGO having HDS of 97.5% and HDN of 90.3%; while non-treated HGO having HDS of 94.9% and HDN of 78.3%. Employing the power law model, the results indicated that for treated HGO the reaction order for both HDS and HDN was 1.50; while for non-treated HGO the reaction order for HDS was 2.25 and for HDN was 2.00. The activation energies were then calculated with 141.4 kJ/mol being obtained for HDS and 113.8 kJ/mol for HDN for treated HGO; while for non-treated HGO the activation energy for HDS was 150.4 kJ/mol and for HDN was 121.4 kJ/mol. It was observed that the conversion of both HDS and HDN were higher and the activation energies were lower for treated HGO, indicating that the removal of non-basic nitrogen species prior to hydrotreatment had a positive impact on catalyst performance and consequently the level of conversion.

No description available.

This study was to investigate the effect on conversion, deactivation of long-term, selectivity of product, and kinetics in deep oxidation of toluene over copper catalyst. The copper catalyst is supported on honeycomb of ceramic monolith (400 cell/inch2). The operation parameters in heterogeneous reactor were performed as follows: 1000 ppm initial concentration of toluene, temperature of reaction in ranging from 200 ¢J to 400 ¢J, 15 % of oxygen concentration, and 4000 hr-1 of space velocity. In the selection of catalyst, we decided to use 20% Cu catalyst for its high conversion, high selectivity and low cost in oxidation of toluene. The conversion of toluene in catalytic reaction was increased with the increasing both of reaction temperature and influent concentration of oxygen, and decreased with the going up of initial concentration of toluene and of space velocity. In the catalyst stability of long-term test, Cu catalysts had a good stability after 7 days reaction in heterogeneous reactor. The tests such as BET, SEM and EA were also determined to verify the stability from surface of catalyst. The kinetics of heterogeneous reactor over Cu catalyst supported on ceramic honeycomb in oxidation of toluene was found that a pseudo-first order could be described by both Power-rate law and Mars-Van Krevelen model. The apparent reaction order and activated energy were obtained in this work.

The processes of development of nuclear weapons resulted in accumulation of thousands of curies of high-level radioactive waste. Liquid waste produced in the US has been stored in carbon steel tanks in highly alkaline (1-3 M NaOH, 6 M sodium salts) media for fifty years and leakage has occurred. One of the approaches to the solution of the problem of radioactive waste is to adsorb the nuclides on highly selective ion-exchange material, solidify in a glass matrix and dispose in a geological formation. The use of the ion-exchange technology is limited by the time of the sorbent-solution contact required to reduce the activity of the streams to acceptable levels. Inorganic ion-exchangers are promising materials due to their high radiation stability, extreme selectivity, and compatibility with the glass matrix. The contact time can be reduced by improving selectivities, kinetics, and capacities of the materials towards the target ions. This can be accomplished in part through understanding of the origin of ion-exchange selectivity. Crystalline zeotypes with minerals sitinakite (ideal formula Na2Ti2O3SiO4??2H2O) and pharmacosiderite (HM3(TO)4(GeO4)x(SiO4)3-x M = Cs+, Na+, K+, T=Nb5+, Ge4+, Ti4+) structures are excellent candidates for selectivity studies because of their ion-exchange properties tunable by alterations of synthetic procedures, and isomorphous framework substitution. The Nb-substitution in titanium sites reduces the framework charge, whereas Ge substitution decreases the unit cell size if in titanium sites and increases if it in silicon sites. The compounds were hydrothermally synthesized in Ti/Si, Ti/Nb/Si, Ti/Ge/Si forms and characterized by structural and ion-exchange studies. The 25% Nb substitution in titanosilicate sitinakite resulted in enhanced selectivity for cesium and additional bond formation of cesium within the channel. The selectivity for cesium in germanium substituted pharmacosiderite also was correlated with the coordination environment within the channel. In the advanced stages of this study semi-crystalline (sodium nonatitanate) and amorphous (monosodium titanate) materials also were considered because of their remarkable strontium selectivity. In situ X-ray diffraction techniques revealed that the sodium nonatitanate precedes the formation of the TS phase in hydrothermal synthesis. This knowledge allowed us to design and synthesize material for combined cesium and strontium removal.

In our previous studies on modeling methyl transfer protein, Ada protein, we found that zinc complexes of tri(2-thiophenyl)phosphine (PS3), (A), have similar methyl transfer behavior as its biological counter part. In order to probe the role of zinc in methylation process, we used tin and cadmium in model study to compare their chemistry relative to that of zinc. We found that all three metal complexes have similar chemistry and assume similar dimeric anion structure. For example, [Cd(PS3)]22-(1) and [Cd(SiPS3)]22-(2) have been successfully characterized crystallographically to possess the same structure as zinc dimer (A). However , in attempt to crystallize the tin analogue, the accidental oxidation product [SnIV(OH)2(SiPS3)]2, (5), was obtained. Its crystal structure gave clue to the mechanism of oxidation of the original tin dimer. The reactions with alkylating reagent of (1) have been compared with those of zinc dimer (A), and we found that the metal (Zn or Cd) center causes the dimers to produce different degree of methylation products toward different alkylating reagents. For the reactions with CH3I, the different degree of methylation between Cd and Zn dimers shows that the presence of zinc center has higher methylation selectivity and weaker reactivity.

We have successfully used the cadmium ion with (2-thiophenyl)phenylphosphine(PS2) or Bis(3-trimethylsilyl-2-thiophenyl)phenylphosphine(SiPS2) to synthesize [(PS2)Cd(TMEDA)](2) and [(SiPS2)Cd(TMEDA)](4) that were structurally similar to [(PS2)Zn(TMEDA)](1). We also obtained a series of zinc complxes [NEt4][(PS2)Zn(SC6H5)](6), [NEt4][{[(PS2)Zn](SC6H11)[(PS2)Zn]}](7) and [NEt4][(PS2)Zn(SCH2C6H5)](8) with systematically varied thiolates. From studying of the methylation reactions of these complexeswith methyliodine or trimethylphosphate, we found that the metal center(zinc or cadmium), ligand(PS2 or SiPS2) or the net charge (neutral ornegative) can influence the reaction time, selectivity of reaction site ormechanism. The zinc complexes (6), (7), and (8) are capable of completingthe catalytic cycle of mthylation-demethylation and hence a good model for related enzyme system.

No description available.

Histone deacetylase (HDAC) inhibition has recently emerged as a novel therapy for cancer treatment. However, currently approved histone deacetylase inhibitors (HDACi) are pan-inhibitors thus inhibiting all 11 zinc dependent HDAC isoforms including those not involved in tumorigenesis. These inhibitors are also associated with various side effects including a potentially fatal cardiotoxicity. To address these issues, isoform selective HDACi were designed and synthesized. The use of 3-hydroxy-pyridin-2-thione (3HPT) as zinc chelation group resulted in small molecules devoid of HDAC1 inhibition but active against HDAC6 and/or 8. Selected 3HPT containing HDACi displayed anticancer activity against various cancer cell lines including DU145, LNCaP and Jurkat. Surprisingly, the lead-compounds were very potent against Jurkat Jγ cells which are resistant to SAHA-induced apoptosis. HDACi were also targeted to cancer cells using folic or pteroic acids as targeting groups. Incorporation of the folic acid into the HDACi pharmacophoric model resulted in inhibitors selective for HDAC6, whereas pteroic-based HDACi inhibited both HDAC1 and 6. Only the pteroic-based inhibitors displayed anticancer activities against folate receptor overexpressing tumors such KB and HeLa. Furthermore, cell-based studies established the inhibition of HDAC1 as the basis for the anticancer activities of the pteroic-based HDACi.

I. Completion of a Total Synthesis of Peloruside A: The completion of a 22 step synthesis of the marine natural product peloruside A is presented. The second generation strategy cuts 10 steps from longest linear sequence of the Evans group’s first generation synthesis of peloruside A by changing the order of fragment coupling operations and maintaining \(C_1\) and \(C_9\) at their final oxidation states over the course of most of the synthesis. Key steps include two highly diastereoselective aldol fragment couplings, a tin tetrachloride mediated hydrosilylation and a macrolactonization on a seco acid containing no cyclic templating elements. II. Studies toward the Total Synthesis of Spiro-Prorocentrimine: The development of an intermolecular Diels–Alder approach toward the marine natural product spiro–prorocentrimine is described. This work began with the adaptation of the Evans group’s previous intramolecular Diels–Alder approach. It was found that protonated imines bearing non-coordinating counterions were of sufficient reactivity to allow cycloaddition to occur even on dienes that were unreactive under the previous best conditions. In the course of these studies, isomerization of a macrocyclic diene during the course of a Diels–Alder reaction complicated the stereochemical outcome of the reaction. Reaction conditions to suppress the isomerization and obtain Diels–Alder adducts bearing the correct configuration at both \(C_9\) and \(C_{33}\) were developed based on a qualitative consideration of the pKas of species present in the reaction. The of several macrocyclic dienes was examined to help explain the course of the Diels–Alder reaction. Other key steps include an iron catalyzed olefin formation, the highly diastereoselective hydrogenation of a trisubstituted olefin in the presence of an enol ether, protecting group studies to suppress the contraction of a 15 membered lactone to a 6 membered lactone and studies of a protecting group strategy to allow installation of a sulfate. Lessons learned from this work and previous efforts are combined in a proposal for a bioinspired synthesis of spiro-prorocentrimine with a longest linear sequence of less than 30 steps. / Chemistry and Chemical Biology