+ Resolve Article
+ Follow Us
Follow on FacebookFollow on Facebook
Follow on TwitterFollow on Twitter

+ Translate
+ Subscribe to Site Feed
GeoScience Most Shared ContentMost Shared Content

Ascertaining p,p'-dimercaptoazobenzene produced from p-aminothiophenol by selective catalytic coupling reaction on silver nanoparticles

, : Ascertaining p,p'-dimercaptoazobenzene produced from p-aminothiophenol by selective catalytic coupling reaction on silver nanoparticles. Langmuir 26(11): 7737-7746

Combining experiment and theory, evidence from surface-enhanced Raman scattering (SERS) were obtained for p,p'-dimercaptoazobenzene (DMAB) produced from p-aminothiophenol (PATP) by selective catalytic coupling reaction on silver nanoparticles. The time-dependent SERS spectra of PATP are consistent with the calculated SERS spectra of DMAB, which is the direct evidence for the production of DMAB from PATP by selective catalytic coupling reaction on silver nanoparticles. The so-called "b(2) modes" of PATP is the -N=N- related vibrational modes of DMAB. The silver nanoparticles could be assembled together to form different size of aggregates with different concentration of PATP solution. When the concentration of Ag nanoparticle (the radius 40 nm) in colloid is 35 pM, the time-dependent SERS of DMAB reveals that the better experimental conditions for observing SERS signals of DMAB are (1) concentration of PATP is around 5 x 10(-6) M in which condition the aggregates consist with about 3-5 silver nanoparticles, which are not too big and suitable for SERS measurement, and (2) the Raman signal will be strongest at the time delay about 27 min for this concentration. By analyzing the symmetry of strong enhanced vibrational modes, it is derived that all of six strong vibrational modes are mostly enhanced by surface plasmons (electromagnetic field). The SERS enhancement calculated with finite-difference time-domain method is on the order of |M|(4) = 9.0 x 10(8) in junctions of AgNPs at 632.8 nm, where |M| = E(loc)/E(in), and E(loc) and E(in) are local and incident electric fields, respectively. The total chemical enhancements, including static chemical and resonant enhancements, are on the order of 10(3).


PMID: 20455558

DOI: 10.1021/la904479q

Other references

Mukherjee, S.; Chen, L-Yu.; Papadimos, T.J.; Huang, S.; Zuraw, B.L.; Pan, Z.K., 2009: Lipopolysaccharide-driven Th2 cytokine production in macrophages is regulated by both MyD88 and TRAM. Gram-negative bacterial lipopolysaccharide (LPS) activates macrophages by interacting with Toll-like receptor 4 (TLR4) and triggers the production of various pro-inflammatory Th1 type (type 1) cytokines such as IFNgamma, TNFalpha, and IL8. Though...

Murray, H.B.; Coniglio, K.; Hartmann, A.S.; Becker, A.E.; Eddy, K.T.; Thomas, J.J., 2017: Are eating disorders "all about control?" The elusive psychopathology of nonfat phobic presentations. There are a subset of individuals with eating disorders (EDs) who do not overevaluate body shape/weight (i.e., nonfat phobic ED; NFP-ED). According to the transdiagnostic cognitive-behavioral conceptualization of EDs, a need for control, in genera...

Krasnjuk, A., 1936: Inbreeding in rye breeding. The problem of freeing rye varieties from the defect of blind spikelets has not been solved by either mass or individual plant selection. By inbreeding, lines with 100 per cent fertility were obtained. On crossing these with a form of exceptionall...

Busch, W.E.; Hirt, J., 1965: Toxoplasmosis. Its Role In Tocogynecology. Prensa Medica Argentina 52: 130-136

Smyth, K.; Hebballi, R.; Peterson, M.K., 2011: Use of transoesophageal echocardiography during the peri-operative period for trauma patients. The medical facility at Camp Bastion continues to evolve as a consequence of the increased throughput of battlefield trauma patients. There is a requirement for rapid and accurate diagnosis of haemodynamic instability and continued haemodynamic mo...

Duggal, R., 1991: Bhore Committee (1946) and its relevance today. Indian Journal of Pediatrics 58(4): 395-406

Yockey, Hubert P., 1997: Walther Lob, Stanley L. Miller and prebiotic building blocks in the silent electrical discharge. It is time to acknowledge Walther Lob's contribution to prebiotic electrochemistry. In the late 19th and early 20th century, Lob exploited the effects of the silent electric discharge to study the electrochemistry of gases with relation to th...

Chawla, A.S.; Krishnan, T.R.; Jackson, A.H.; Scalabrin, D.A., 1988: Alkaloidal constituents of Erythrina variegata bark. Four alkaloids, erysotine (9), erythratidine (10), epi-erythratidine (11), and 11-hydroxy-epi-erythratidine (12) have been characterized in Erythrina variegata bark in addition to those previously reported.

Unsalaner, C., 1941: A Preliminary Description of the Carboniforous and Devonian Fauna Discovered in the Western Taurus. Maden Tetkik ve Arama Ankara, 64/35: 594-603

Grushko, V.; Lübben, O.; Chaika, A.N.; Novikov, N.; Mitskevich, E.; Chepugov, A.; Lysenko, O.; Murphy, B.E.; Krasnikov, S.A.; Shvets, I.V., 2013: Atomically resolved STM imaging with a diamond tip: simulation and experiment. The spatial resolution of a scanning tunneling microscope (STM) can be enhanced using light element-terminated probes with spatially localized electron orbitals at the apex atom. Conductive diamond probes can provide carbon atomic orbitals suitabl...