One step to detect the latent fingermarks with gold nanoparticles

A simple and environment friendly chemical route for detecting latent fingermarks by one-step single-metal nanoparticles deposition method (SND) was achieved successfully on several non-porous items. Gold nanoparticles (AuNPs) synthesized using sodium borohydride as reducing agent in the presence of glucose, were used as working solution for latent fingermarks detection. The SND technique just needs one step to obtain clear ridge details in a wide pH range (2.5-5.0), whereas the standard multi-metal deposition (MMD) technique requires six baths in a narrow pH range (2.5-2.8). The SND is very convenient to detect latent fingermarks in forensic scene or laboratory for forensic operators. The SND technique provided sharp and clear development of latent fingermarks, without background staining, dramatically diminished the bath steps.

A Novel Strategy to Branched Polyacrylonitrile Via One-Pot RAFT Copolymerization of Acrylonitrile and an Asymmetrical Divinyl Monomer

Branched polyacrylonitriles were prepared via the one-pot radical copolymerization of acrylonitirle and an asymmetric divinyl monomer (allyl methacrylate) that possesses both a higher reactive methacrylate and a lower reactive allyl. RAFT technique was used to keep a low-propagation chain concentration via a fast reversible chain transfer euilibration and thus the cross-linking was prevented until a high level of monomer conversions. This novel strategy was demonstrated to engenerate a branched architecture with abundant pendant functional vinyl and nitrile groups, and controlled molecular weight as a behavior of controlled/living radical polymerization characteristics. The effect of the various experimental parameters, including temperature, brancher to monomer molar ratio, and chain transfer agent to initiator molar ratio, on the control Of moleculer dimension (molecular weight and polydispersity indices) and the degree of branching were investigated in detail. Moreover, H-1 NMR and gel permeation chromatography confirm the branched architecture of the resultant polymer. The intrinsic viscosity of the copolymer is also lower than the linear counterpart.

A general route to prepare one- and three-dimensional carbon nanotube/metal nanoparticle composite nanostructures

Adsorption of polyethyleneimine (PEI)-metal ion complexes onto the surfaces of carbon nanotubes (CNTs) and subsequent reduction of the metal ion leads to the fabrication of one-dimensional CNT/metal nanoparticle (CNT/M NP) heterogeneous nanostructures. Alternating adsorption of PEI-metal ion complexes and CNTs on substrates results in the formation of multilayered CNT films. After exposing the films to NaBH4, three-dimensional CNT composite films embedded with metal nanoparticles (NPs) are obtained. UV-visible spectroscopy, scanning electron microscopy, and X-ray photoelectron spectroscopy are used to characterize the film assembly. The resulting (CNT/M NP)(n) films inherit the properties from both the metal NPs and CNTs that exhibit unique performance in surface-enhanced Raman scattering (SERS) and electrocatalytic activities to the reduction of O-2; as a result, they are more attractive compared to (CNT/polyelectrolyte)(n) and (NP/polyelectrolyte)(n) films because of their multifunctionality.

An one-pot epitaxial growth method to synthesize cactus-like ZnO

In this work, we have developed a one-pot, morphology controlled epitaxial growth method to synthesize novel cactus-like ZnO in solution. Utilizing zinc acetate and hexamethylenetetramine as the precursors, ZnO nanorods synthesized in the first step remained in the solution, without any separation, served directly as the matrix for the epitaxial growth in the second step. Control experiments revealed that a proper mass of precursors added in the second step was crucial to form cactus-like ZnO. The as-synthesized ZnO was single crystalline and possessed three photoluminescence emissions centered at 390, 425 and 490 run. Finally, a possible mechanism for the epitaxial growth ZnO was proposed and discussed.

One-step polyelectrolyte-based route to well-dispersed gold nanoparticles: Synthesis and insight

Polyelectrolytes have been widely used as building blocks for the creation of thickness-controllable multilayer thin films in a layer-by-layer fashion, and also been used as flocculants or stabilizer of colloids. This paper reports novel finding that a kind of polyelectrolyte, polyamines, can facilely induce HAuCl4 to spontaneously form well-stabilized gold nanoparticles without the additional step of introducing a reducing reagent during the elevation of temperature, even at room temperature in some cases. The polymer chain-confined microenvironment and the acid-induced evolution of amide of such kind of polyelectrolyte solution play an important role in the nucleation and growth of gold nanoparticles. This method would not only be helpful to gain an insight into the formation of gold nanoparticles in polyelectrolyte systems, but also provide a novel and facile one-step polyelectrolyte-based synthetic route to polyelectrolyte protected gold nanoparticles in aqueous media for potential applications. More importantly, this strategy will be general to the preparation of other nanoparticles.

The chemical resolution of racemic cis-2-hydroxymethyl-5(cytosine-1 '-yl)-1,3-oxathiolane (BCH-189)-one direct method to obtain lamivudine as anti-HIV and anti-HBV agent

Racemic cis-BCH-189 can be resolved to (-)-enantiomer (lamivudine) and (+)-enantiomer by esterification of cis-2-hydroxymethyl-5-(N-4(')-acetylcytosine-1'-yl)-1,3-oxathiolane and (+)-menthyl chloroformate in CH3CN with pyridine as base. The two diastereomers of ester were seperated by recrystallization in methanol at 0degreesC. Lamivudine was obtained by deprotection of (-)-diastereomer with high yield.

A one-pot procedure to prepare S-protected 4-iodothiophenols

By means of non-aqueous reduction of pipsyl chloride followed by treatment with K2CO3 and then reacting with acetyl chloride or benzyl chloride, S-acetyl/benzyl -4-iodothiophenols were obtained in a one-pot procedure with yield as high as 90%. These S-protected arenethiols are very important intermediates to synthesize self-assembled molecular wires.

A one-pot procedure to prepare ethynylferrocene and iodoethynylferrocene

Ethynylferrocene and iodoethynylferrocene were prepared in high yield as 88-90% through a one-pot procedure. 1, 1'-diiodoferrocenylene was in-situ prepared from reaction of CHI3 PPh3, t-BuOK and ferrocenecarboxaldehyde, further reaction with t-BuOK or n-BuLi gave the title compounds.

One-step heterogeneously catalytic oxidation of o-cresol by oxygen to salicylaldehyde

Salicylaldehyde (selectivity = 57.3% at a conversion = 73.8%) was prepared for the first time by the oxidation of o-cresol in a single step using impregnated CuCo/C catalysts.

A brief history of the Bhopal principality in Central India : from the period of its foundation, about one hundred and fifty years ago, to the present time.

http://www.archive.org/details/briefhistoryofth014373mbp

The centrality of event scale: a measure of integrating a trauma into one's identity and its relation to post-traumatic stress disorder symptoms.

We introduce a new scale that measures how central an event is to a person's identity and life story. For the most stressful or traumatic event in a person's life, the full 20-item Centrality of Event Scale (CES) and the short 7-item scale are reliable (alpha's of .94 and .88, respectively) in a sample of 707 undergraduates. The scale correlates .38 with PTSD symptom severity and .23 with depression. The present findings are discussed in relation to previous work on individual differences related to PTSD symptoms. Possible connections between the CES and measures of maladaptive attributions and rumination are considered along with suggestions for future research.

But no one in my family has been to university - aiming higher: school students attitudes to higher education

In this paper, we present findings from the second stage of a three year longitudinal study involving 3,570 students aged 13-18 in a London Borough looking at the impact of Widening Participation (WP) on the attitudes of students. We outline findings from a previous stage and then focus specifically on two cohorts of Year 10 students (aged 14-15) in two consecutive years. The students completed the specially designed Attitudes to Higher Education Questionnaire (AHEQ) and provided information on WP activities in which they had participated. Data on the students' academic attainment and social backgrounds were also included. There were significant sex and cohort differences and interactions which were found to be related to WP activities specifically aimed at increasing the participation of socially disadvantaged students in higher education. The implications of findings are discussed in relation to theories of social identity and self concept and the implementation of strategies to increase participation in Higher Education