Synthesis and characterization of zeolite Linde Type W and its metal oxide composite Ag-O-LTW used for the decontamination of chemical warfare agent simulant

Abstract

In this study, we have evaluated the performance of novel adsorbent zeolite Linde Type W and modified LTW with AgO metal oxide composite for the decontamination of chemical warfare agent simulant 2-chloroethylphenylsulphide (CEPS). Zeolites are nanoporous aluminosilicate minerals composed of silicon, aluminum and oxygen framework with cations and water molecules within the pores. The synthesized zeolite LTW and its composites Ag-O-LTW was characterized by XRD, FTIR, SEM-EDS and BET analytical techniques. The decontamination study of CWA simulant, CEPS was monitored by using GC-FID technique. The nanocrystalline zeolite LTW and Ag-O-LTW composites were found powerful adsorbents and showed great decontamination potential toward CWA simulant CEPS. The Ag-O-LTW showed better results (～98 % decontamination in 7?hours) than LTW zeolite.     

Computational chemistry at Janssen

Computer-aided drug discovery activities at Janssen are carried out by scientists in the Computational Chemistry group of the Discovery Sciences organization. This perspective gives an overview of the organizational and operational structure, the science, internal and external collaborations, and the impact of the group on Drug Discovery at Janssen.     

Imidazolinium salts derived from amino[2.2]paracyclophane compounds: synthesis and hydrolytic ring-opening

The synthesis of a series of imidazolinium chlorides containing the [2.2]paracyclophane scaffold is described. Attempts to deprotonate the salts with strong bases resulted in hydrolytic ring-opening and yielded N-formylethylenediamine products rather than the intended free carbenes.     

Density and speed of sound measurements of hexadecane

The density and speed of sound of hexadecane have been measured with two instruments. Both instruments use the vibrating-tube method for measuring density. Ambient pressure (83 kPa) density and speed of sound were measured with a commercial instrument from T = (290.65 to 343.15) K. Adiabatic compressibilities are derived from the density and speed of sound data at ambient pressure. Compressed liquid density was measured in a second instrument and ranged from T = (310 to 470) K with pressures from (1 to 50) MPa. The overall relative expanded uncertainty of the compressed liquid density measurements is 0.10–0.13% (k = 2). The overall relative expanded uncertainty (k = 2.3) of the speed of sound measurements is 0.2% and that of the ambient pressure density measurements is approximately 0.04% (k = 2.3). The ambient pressure and compressed liquid density measurements are correlated within 0.1% with a modified Tait equation.     

Effect of intonation on cantonese lexical tones

In tonal languages, there are potential conflicts between the FO-based changes due to the coexistence of intonation and lexical tones. In the present study, the interaction of tone and intonation in Cantonese was examined using acoustic and perceptual analyses. The acoustic patterns of tones at the initial, medial, and final positions of questions and statements were measured. Results showed that intonation affects both the FO level and contour, while the duration of the six tones varied as a function of positions within intonation contexts. All six tones at the final position of questions showed rising FO contour, regardless of their canonical form. Listeners were overall more accurate in the identification of tones presented within the original carrier than of the same tones in isolation. However, a large proportion of tones 33, 21, 23, and 22 at the final position of questions were misperceived as tone 25 both within the original carrier and as isolated words. These results suggest that although the intonation context provided cues for correct tone identification, the intonation-induced changes in FO contour cannot always be perceptually compensated for, resulting in some erroneous perception of the identity of Cantonese tone.     

Ring-opening polymerization of gold macrocycles and self-assembly of a coordination polymer through hydrogen-bonding

The equilibrium between digold and tetragold rings and a ring-opened oligomer and polymer is established by NMR and ESI-MS studies in solution and by structure determinations in the solid state; the polymer containing amide-derivatized ligands undergoes self-assembly through hydrogen bonding to give an ordered network.     

Alpha-lactalbumin tertiary structure changes on hydrophobic interaction chromatography surfaces

Hydrogen exchange (HX) detected by mass spectrometry (MS) was used to analyze the structure of calcium-free alpha-lactalbumin, a model protein with marginal stability. Two chromatographic peaks were observed from samples of pure protein eluted from SOURCE phenyl hydrophobic interaction chromatography (HIC) media. Whole-protein HX measurements showed that the less-retained peak had solvent exposure similar to native protein in the absence of the HIC surface while the retained protein was nearly, although not fully, solvent exposed. The formation of these two peaks was kinetically limited. The protein also refolded successfully following elution. In addition, proteolytic fragmentation was used to analyze HX at the peptide level. This approach revealed that helix C was the most stable region of alpha-lactalbumin under native conditions and in the flow-through peak. Helix C also formed the core of residual native structure in the partially unfolded protein in the retained peak. The results suggest that residues that are most solvent accessible under native conditions may be those most likely to unfold upon adsorption.