Browse
Submit Data
Databases
API
Help

Dataset Information

21 Views

0 Connections

0 Citations

0 Reanalyses

0 Downloads

Omics score: 0

Enhanced photo-reactivity of polyanthracene in the VIS region.

ABSTRACT: The wavelength-dependent photo-reactivity of polyanthracene was explored upon UV-C and VIS light irradiation. The material was prepared via one-pot chemical oxidation route using FeCl3 as oxidizing agent. A decrease in surface hydrophobicity of a polyanthracene-coated poly(methylmethacrylate) substrate from 109.11° to 60.82° was observed upon UV-C exposure for 48 hrs which was attributed to increase in oxygen content at the surface, as validated by energy dispersive X-ray spectroscopy. Upon exposure to ultraviolet-visible LEDs, photo-dimerization of polyanthracene in solution occurred and was monitored using UV-VIS spectroscopy. The photo-dimer product formation decreased from 381 nm to 468 nm and was found to be higher for the polyanthracene material compared to the monomer anthracene. At 381 nm, photo-dimerization of the material was found to be approx. 4x more efficient than the non-substituted monomer counterpart. Results obtained show that photo-dimerization of polyanthracene will proceed upon exposure with visible light LEDs with reduction in efficiency at longer wavelengths. To compensate, irradiation power of the light source and irradiation time were increased.

SUBMITTER: Bruzon DA

PROVIDER: S-EPMC9269904 | biostudies-literature |

REPOSITORIES: biostudies-literature

ACCESS DATA

Json Xml

Similar Datasets

Photo-Reduction of CO? by VIS Light on Polythiophene-ZSM-5 Zeolite Hybrid Photo-Catalyst.

Project description:A new hybrid photo-catalyst based on ZSM-5 zeolite suitable for reduction of carbon dioxide was synthesized. The photo-catalyst was prepared by oxidative polymerization of thiophene with FeCl? in the presence of ZSM-5 with participation of ultrasound. The synthesized photo-catalyst strongly absorbs light radiation up to approx. 650 nm, with the absorption edge in the NIR region. Reactive radicals were generated by VIS light irradiation in an aqueous suspension consisting of the photo-catalyst with CO?. Formic acid and acetic acid were generated as the main products of the CO? reduction. EPR spin trapping technique was applied to identify the reactive radical intermediates. In this work, the mechanism of product formation is also discussed.

| S-EPMC6429064 | biostudies-literature

Multi-phase functionalization of titanium for enhanced photon absorption in the vis-NIR region.

Project description:Inadequate absorption of Near Infrared (NIR) photons by conventional silicon solar cells has been a major stumbling block towards the attainment of a high efficiency "full spectrum" solar cell. An effective enhancement in the absorption of such photons is desired as they account for a considerable portion of the tappable solar energy. In this work, we report a remarkable gain observed in the absorption of photons in the near infrared and visible region (400 nm-1000 nm) by a novel multi-phased oxide of titanium. Synthesised via a single step ultra-fast laser pulse interaction with pure titanium, characterisation studies have identified this oxide of titanium to be multi-phased and composed of Ti3O, (TiO.716)3.76 and TiO2 (rutile). Computed to have an average band gap value of 2.39 eV, this ultrafast laser induced multi-phased titanium oxide has especially exhibited steady absorption capability in the NIR range of 750-1000 nm, which to the best of our knowledge, was never reported before. The unique NIR absorption properties of the laser functionalised titanium coupled with the simplicity and versatility of the ultrafast laser interaction process involved thereby provides tremendous potential towards the photon sensitization of titanium and thereafter for the inception of a "full spectrum" solar device.

| S-EPMC4609984 | biostudies-other

Plasmon-enhanced reduced graphene oxide photodetector with monometallic of Au and Ag nanoparticles at VIS-NIR region.

Project description:Hybrids plasmonic nanoparticles (NPs) and unique 2D graphene significantly enhanced the photoresponse of the photodetectors. The metallic NPs that exhibit localized surface plasmon resonance (LSPR) improves strong light absorption, scattering and localized electromagnetic field by the incident photons depending on the optimum condition of NPs. We report high-performance photodetectors based on reduced graphene oxide (rGO) integrated with monometallic of Au and Ag nanoparticles via a familiar fabrication technique using an electron beam evaporation machine. Under 680 nm illumination of light, our rGO photodetector exhibited the highest performance for Au-rGO with the highest responsivity of 67.46 AW-1 and the highest specific detectivity (2.39 × 1013 Jones). Meanwhile, Ag-rGO achieved the highest responsivity of 17.23 AW-1, specific detectivity (7.17 × 1011 Jones) at 785 nm. The response time are 0.146 µs and 0.135 µs for Au-rGO and Ag-rGO respectively for both wavelengths. The proposed photodetector with combining monometallic and graphene provide a new strategy to construct reliable and next-generation optoelectronic devices at VIS-NIR region.

| S-EPMC8490468 | biostudies-literature

Broadband cavity enhanced UV-VIS absorption spectroscopy for picolitre liquid samples.

Project description:Absorption spectroscopy is a widely used analytical technique due to its label-free nature, however its application to small liquid samples is hampered by the associated short absorption pathlengths, which limit sensitivity. A novel concept for the development of an ultrasensitive broadband absorption spectrometer optimised for thin liquid films is presented here. To enhance sensitivity of the absorbance measurements an optical cavity is implemented on a fibre-based absorption spectrometer (CEASpec). Light is circulated multiple times through the sample of interest to increase sensitivity. The bandwidth of the instrument is chosen by the choice of the dielectric mirrors forming the optical cavity spectra and, in this implementation, has been set to be 200 nm wide (250-450 nm). The sensing volume of the spectroscope is prescribed by the choice of optical fibres employed to deliver light to the sample, and in this implementation fibres of 400 μm in diameter were employed, giving a sensing volume of 630 picolitres for a thin film of 5 μm in thickness. Amphotericin B, a broad light absorber in the 280-450 nm region of the spectrum, was used here to prove the capabilities of the proposed cavity enhanced absorption spectroscope. Cavity enhancement factors, the equivalent pathlength increase over classical absorption spectroscopy, in the range of 200× have been achieved across a broad wavelength range.

| S-EPMC10089060 | biostudies-literature

Photo-enhanced Aqueous Solubilization of an Azo-compound.

Project description:We previously showed that disruption of intermolecular interactions, e.g., by lowering the molecular planarity and/or introducing bent structures, improves the aqueous solubility of compounds, and based upon that work, we hypothesized that azobenzene trans-to-cis photoswitching could also be utilized to enhance the aqueous solubility of compounds. Here, we demonstrate that UV/visible light irradiation can reversibly switch the aqueous solubilization of an anti-cancer candidate drug, a low-molecular-weight kinase inhibitor bearing an azobenzene moiety. The increase of solubilization associated with UV-induced trans-to-cis conversion may have clinical relevance, because the time-scale of thermal cis-to-trans reversion at 37?°C is longer than that of oral absorption.

| S-EPMC5537305 | biostudies-literature

Carbon/Graphene-Modified Titania with Enhanced Photocatalytic Activity under UV and Vis Irradiation.

Project description:Laser synthesis was used for one-step synthesis of titania/graphene composites (G-TiO2 (C)) from a suspension of 0.04 wt% commercial reduced graphene oxide (rGO) dispersed in liquid titanium tetraisopropoxide (TTIP). Reference titania sample (TiO2(C)) was prepared by the same method without graphene addition. Both samples and commercial titania P25 were characterized by various methods and tested under UV/vis irradiation for oxidative decomposition of acetic acid and dehydrogenation of methanol (with and without Pt co-catalyst addition), and under vis irradiation for phenol degradation and inactivation of Escherichia coli. It was found that both samples (TiO2(C) and G-TiO2(C)) contained carbon resulting from TTIP and C2H4 (used as a synthesis sensitizer), which activated titania towards vis activity. The photocatalytic activity under UV/vis irradiation was like that by P25. The highest activity of TiO2(C) sample for acetic acid oxidation was probably caused by its surface enrichment with hydroxyl groups. G-TiO2(C) was the most active for methanol dehydrogenation in the absence of platinum (ca. five times higher activity than that by TiO2(C) and P25), suggesting that graphene works as a co-catalyst for hydrogen evolution. High activity under both UV and vis irradiation for decomposition of organic compounds, hydrogen evolution and inactivation of bacteria suggests that laser synthesis allows preparation of cheap (carbon-modified) and efficient photocatalysts for broad environmental applications.

| S-EPMC6947090 | biostudies-literature

Mechanisms of enhanced vascular reactivity in preeclampsia.

Project description:Preeclamptic women have enhanced blood pressure response to angiotensin II and extensive systemic vascular infiltration of neutrophils. Neutrophils release reactive oxygen species that might activate the RhoA kinase pathway to enhance vascular reactivity. We hypothesized that enhanced vascular reactivity in preeclampsia is attributed to neutrophil-mediated reactive oxygen species activation of the RhoA kinase pathway. Omental arteries were obtained at cesarean section and studied using a myograph system. We found that arteries of preeclamptic women had extensive infiltration of neutrophils and enhanced reactivity to angiotensin II. Treatment of arteries of normal pregnant women with reactive oxygen species or activated neutrophils enhanced vessel reactivity to angiotensin II mimicking preeclamptic vessels. Pretreatment with superoxide dismutase/catalase to quench reactive oxygen species or RhoA kinase inhibitor blocked enhanced responses in preeclamptic and normal vessels. Reactive oxygen species also enhanced vessel reactivity to norepinephrine, which was blocked by RhoA kinase inhibition. Treatment of arteries with reactive oxygen species increased RhoA kinase activity 3-fold, whereas culture of human vascular smooth muscle cells with angiotensin II and activated neutrophils or reactive oxygen species resulted in phosphorylation of key proteins in the RhoA kinase pathway. We conclude that enhanced vascular reactivity of omental arteries in preeclampsia is attributed to reactive oxygen species activation of the RhoA kinase pathway and that enhanced vascular reactivity is likely attributed to the infiltration of neutrophils. We speculate that neutrophil infiltration into systemic vasculature of preeclamptic women is an important mechanism for hypertension.

| S-EPMC3212870 | biostudies-literature

Photo-induced carbocation-enhanced charge transport in single-molecule junctions.

Project description:We report the first example of photo-induced carbocation-enhanced charge transport in triphenylmethane junctions using the scanning tunneling microscopy break junction (STM-BJ) technique. The electrical conductance of the carbocation state is enhanced by up to 1.5 orders of magnitude compared to the initial state, with stability lasting for at least 7 days. Moreover, we can achieve light-induced reversible conductance switching with a high ON-OFF ratio in carbocation-based single-molecule junctions. Theoretical calculations reveal that the conductance increase is due to a significant decrease of the HOMO-LUMO gap and also the enhanced transmission close to the Fermi levels when the carbocation forms. Our findings encourage continued research toward developing optoelectronics and carbocation-based devices at the single-molecule level.

| S-EPMC8159380 | biostudies-literature

Scientific imperatives vis-a-vis growing inequality in America.

Project description:A landmark article published in the American Psychologist (Adler et al., 1994) encouraged psychologists to engage in research on socioeconomic inequality and health. Numerous contributions followed to fill in psychosocial and behavioral pathways. Specifically, we review advances on health inequalities research from a large public-use study (Midlife in the United States [MIDUS]). The Great Recession of 2007 to 2009 and its lingering effects are then reviewed to underscore widening inequality in access to education, employment, and income. Two MIDUS national samples of same-aged adults recruited 2 decades apart are then compared to assess historical changes in socioeconomic, physical health, and well-being profiles from the 1990s to postrecession. Despite historical gains in educational attainment over time, we show that indicators of socioeconomic status, health, and well-being are more compromised in the postrecession sample relative to the 1990s sample. Building on these preliminary findings, we elaborate opportunities for further inquiry by the scientific community to examine whether widening socioeconomic inequalities exacerbated by the Great Recession translate to widening health inequalities. (PsycINFO Database Record (c) 2019 APA, all rights reserved).

| S-EPMC6776687 | biostudies-literature

Arthroscopic Distal Clavical Resection Using "Vis-a-Vis" Portal.

Project description:Arthroscopic distal clavicle resection has become an increasingly popular procedure in orthopaedics, and various techniques have been published. Many of the arthroscopic distal clavicle resection techniques that have been reported require visualization from the lateral portal with an anterior working portal to perform the resection. While these techniques have reported high success rates, there is often difficulty in viewing the entire acromioclavicular joint from the 2 standard arthroscopic portals (lateral and anterior). This is due to the medial edge of the acromion blocking the ability to visualize the most superior and posterior portions of the distal clavicle. We propose a technique for arthroscopic distal clavicle resection using an accessory anterior portal.

| S-EPMC5021634 | biostudies-literature

OmicsDI is part of the ELIXIR infrastructure

OmicsDI is an Elixir interoperability service. Learn more ›

Tweets

OmicsDI Databases

PRIDE
PeptideAtlas
MassIVE
JPOST Repository
Physiome Model Repository

EGA
EVA
ENA
LINCS
PAXDB
Cell Collective

MetaboLights
Metabolomics Workbench
MetabolomeExpress
GNPS
BioModels
FAIRDOMHub

ArrayExpress
dbGaP
ExpressionAtlas
GEO
NODE

Information

Databases
Help
API
Contact us
Code on GitHub
Terms of use
Submit Data