28,895 results match your criteria Photochemical & photobiological sciences : Official journal of the European Photochemistry Association and the European Society for Photobiology[Journal]


Catalyzed Gasoline Particulate Filters Reduce Secondary Organic Aerosol Production from Gasoline Direct Injection Vehicles.

Environ Sci Technol 2019 Feb 22. Epub 2019 Feb 22.

The effects of photochemical aging on exhaust emissions from two light-duty vehicles with gasoline direct injection (GDI) engines equipped with and without catalyzed gasoline particle filters (GPFs) were investigated using a mobile environmental chamber. Both vehicles with and without the GPFs were exercised over the LA92 drive cycle using a chassis dynamometer. Diluted exhaust emissions from the entire LA92 cycle were introduced to the mobile chamber and subsequently photochemically reacted. Read More

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http://dx.doi.org/10.1021/acs.est.8b06418DOI Listing
February 2019

Targeting the Next Generation of Deep-Ultraviolet Nonlinear Optical Materials: Expanding from Borates to Borate Fluorides to Fluorooxoborates.

Acc Chem Res 2019 Feb 22. Epub 2019 Feb 22.

CAS Key Laboratory of Functional Materials and Devices for Special Environments , Xinjiang Technical Institute of Physics & Chemistry, CAS, and Xinjiang Key Laboratory of Electronic Information Materials and Devices , 40-1 South Beijing Road , Urumqi 830011 , China.

Coherent light radiation down to the deep-ultraviolet spectral range (λ < 200 nm) produced by common laser sources is extensively used in diverse fields ranging from ultrahigh-resolution photolithography to photochemical synthesis to high-precision microprocessing. Actually, it is hard to immediately obtain certain wavelengths, deep-ultraviolet coherent light in particular, from commercial laser sources. However, the direct second harmonic generation process governed in part by nonlinear optical crystals is a feasible and effective approach to generate deep-ultraviolet coherent light, which motivates chemists and materials scientists to find potential deep-ultraviolet nonlinear optical materials that can practically meet the scientific requirements. Read More

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http://dx.doi.org/10.1021/acs.accounts.8b00649DOI Listing
February 2019

Colloidal semiconductor nanocrystals in energy transfer reactions.

Chem Commun (Camb) 2019 Feb 22. Epub 2019 Feb 22.

Department of Physics and Astronomy, Bowling Green State University, Bowling Green, Ohio 43403, USA. and The Center for Photochemical Sciences, Bowling Green State University, Bowling Green, Ohio 43403, USA.

Excitonic energy transfer is a versatile mechanism by which colloidal semiconductor nanocrystals can interact with a variety of nanoscale species. While this process is analogous to dipole-dipole coupling in molecular systems, the corresponding energy transfer dynamics can deviate from that of molecular assemblies due to manifestations of bulk-like features in semiconductor colloids. In particular, weak exciton binding, small singlet-triplet exciton splitting, and the energy disorder across nanocrystal ensembles can all play distinctive roles in the ensuing energy conversion processes. Read More

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http://dx.doi.org/10.1039/c9cc00162jDOI Listing
February 2019

Photochemical and Photocatalytic Degradation of 1-Propanol Using UV/H O : Identification of Malonate as Byproduct.

Electrophoresis 2019 Feb 22. Epub 2019 Feb 22.

Department of Chemistry, Clemson University,, ,, Clemson, South Carolina, United States.

1-propanol is a primary alcohol extensively used in the pharmaceutical, chemical, and food industries. It has been also found as a contaminant in the atmosphere and it is considered a model compound to mimic the behavior and fate of aliphatic alcohols exposed to environmental conditions. In order to understand that role of relevant variables, this paper presents results obtained with a simple experimental set-up to investigate the reactivity of 1-propanol under mild oxidizing conditions. Read More

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http://dx.doi.org/10.1002/elps.201900001DOI Listing
February 2019

Early photophysical events of a ruthenium(ii) molecular dyad capable of performing photochemical water oxidation and of its model compounds.

Photochem Photobiol Sci 2019 Feb 22. Epub 2019 Feb 22.

Department of Chemistry, University of Houston, 112 Fleming Building, Houston, Texas 77204-5003, USA.

The early photophysical events occurring in the dinuclear metal complex [(ttb-terpy)(I)Ru(μ-dntpz)Ru(bpy)2]3+ (2; ttb-terpy = 4,4',4''-tri-tert-butyl-terpy; bpy = 2,2'-bipyridine; dntpz = 2,5-di-(1,8-dinaphthyrid-2-yl)pyrazine) - a species containing the chromophoric {(bpy)2Ru(μ-dntpz)}2+ subunit and the catalytic {(I)(ttb-terpy)Ru(μ-dntpz)}+ unit, already reported to be able to perform photocatalytic water oxidation - have been studied by ultrafast pump-probe spectroscopy in acetonitrile solution. The model species [Ru(bpy)2(dntpz)]2+ (1), [(bpy)2Ru(μ-dntpz)Ru(bpy)2]4+ (3), and [(ttb-terpy)(I)Ru((μ-dntpz)Ru[(ttb-terpy)(I)]2+ (4) have also been studied. For completeness, the absorption spectra, redox behavior of 1-4 and the spectroelectrochemistry of the dinuclear species 2-4 have been investigated. Read More

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http://dx.doi.org/10.1039/c8pp00530cDOI Listing
February 2019

Heteroarylcarbene - Arylnitrene Radical Cation Isomerizations.

J Phys Chem A 2019 Feb 21. Epub 2019 Feb 21.

5-Phenyltetrazole 1e is an important source of phenylnitrene or the phenylnitrene radical cation (m/z 91) under thermal, photochemical and electron impact conditions. Similarly, 3- or 4-(5-tetrazolyl)pyridines 12b,c yield pyridylnitrene radical cations 9a.+ (m/z 92) on electron impact. Read More

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http://dx.doi.org/10.1021/acs.jpca.9b00309DOI Listing
February 2019

Recent Developments in the Interactions of Classic Intercalated Ruthenium Compounds: [Ru(bpy)₂dppz] and [Ru(phen)₂dppz] with a DNA Molecule.

Molecules 2019 Feb 20;24(4). Epub 2019 Feb 20.

Laboratory of Functional Molecules and Materials, School of Physics and Optoelectronic Engineering, Shandong University of Technology, Zibo 255000, China.

[Ru(bpy)₂dppz] and [Ru(phen)₂dppz] as the light switches of the deoxyribose nucleic acid (DNA) molecule have attracted much attention and have become a powerful tool for exploring the structure of the DNA helix. Their interactions have been intensively studied because of the excellent photophysical and photochemical properties of ruthenium compounds. In this perspective, this review describes the recent developments in the interactions of these two classic intercalated compounds with a DNA helix. Read More

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http://dx.doi.org/10.3390/molecules24040769DOI Listing
February 2019

Transformation Products of Organic Contaminants and Residues-Overview of Current Simulation Methods.

Molecules 2019 Feb 19;24(4). Epub 2019 Feb 19.

Department of Analytical Chemistry and Reference Materials, Bundesanstalt für Materialforschung und-prüfung (BAM), Richard-Willstätter-Straße 11, 12489 Berlin, Germany.

The formation of transformation products (TPs) from contaminants and residues is becoming an increasing focus of scientific community. All organic compounds can form different TPs, thus demonstrating the complexity and interdisciplinarity of this topic. The properties of TPs could stand in relation to the unchanged substance or be more harmful and persistent. Read More

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http://dx.doi.org/10.3390/molecules24040753DOI Listing
February 2019

Excited state charge transfer in covalently functionalized MoS2 with zinc phthalocyanine donor-acceptor hybrid.

Angew Chem Int Ed Engl 2019 Feb 21. Epub 2019 Feb 21.

National Hellenic Research Foundation, Theoretical and Physical Chemistry Institute, 48 Vassileos Constantinou Avenue, 11635, Athens, GREECE.

Functionalization of MoS2 is of paramount importance tailoring its properties towards optoelectronic applications and unlocking its full potential. Zinc phthalocyanine (ZnPc) carrying an 1,2-dithiolane oxide linker was employed to functionalize MoS2 at defected sites located at the edges. The structure of ZnPc-MoS2 was fully assessed by complementary spectroscopic, thermal and microscopy imaging techniques. Read More

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http://dx.doi.org/10.1002/anie.201900101DOI Listing
February 2019

Cell-free soluble expression of the membrane protein PsbS.

Protein Expr Purif 2019 Feb 18. Epub 2019 Feb 18.

Dept. of Solid-State NMR, Leiden Institute of Chemistry, Leiden University, Einsteinweg 55, 2300RA, Leiden, the Netherlands. Electronic address:

Photosystem II subunit S (PsbS) is a membrane protein that plays an exclusive role in non-photochemical quenching for photoprotection of plants under high-light conditions. The activation mechanism of PsbS and its pH-induced conformational changes are currently unknown. For structural investigation of PsbS, effective synthesis of PsbS with selective isotope or electron-spin labels or non-natural amino acids incorporated would be a great asset. Read More

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http://dx.doi.org/10.1016/j.pep.2019.02.010DOI Listing
February 2019

Recent Advances in n-Type Polymers for All-Polymer Solar Cells.

Adv Mater 2019 Feb 21:e1807275. Epub 2019 Feb 21.

Flinders Institute for Nanoscale Science and Technology, Flinders University, Sturt Road, Bedford Park, Adelaide, SA, 5042, Australia.

All-polymer solar cells (all-PSCs) based on n- and p-type polymers have emerged as promising alternatives to fullerene-based solar cells due to their unique advantages such as good chemical and electronic adjustability, and better thermal and photochemical stabilities. Rapid advances have been made in the development of n-type polymers consisting of various electron acceptor units for all-PSCs. So far, more than 200 n-type polymer acceptors have been reported. Read More

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http://dx.doi.org/10.1002/adma.201807275DOI Listing
February 2019

Dendron-polymer Conjugate based Crosslinked Micelles: A Robust and Versatile Nanosystem for Targeted Delivery.

Bioconjug Chem 2019 Feb 21. Epub 2019 Feb 21.

Among various nanomedicine platforms, biodegradable polymeric micelles offer a viable approach to targeted cancer therapy. Herein, we report fabrication of core-crosslinked micelles using dendron-polymer conjugates as building blocks. Hydrophobic polyester dendrons containing peripheral alkene groups are conjugated to a hydrophilic poly(ethylene glycol) based copolymer bearing activated ester groups for appending an amine-containing peptide based targeting group, namely, cRGDfK. Read More

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http://dx.doi.org/10.1021/acs.bioconjchem.9b00027DOI Listing
February 2019

Gold(II) Porphyrins in Photoinduced Electron Transfer Reactions.

Chemistry 2019 Feb 20. Epub 2019 Feb 20.

Johannes Gutenberg-University Mainz, Institute of Inorganic and Analytical Chemistry, Duesbergweg 10-14, 55128, Mainz, GERMANY.

In the context of solar to chemical energy conversion inspired by natural photosynthesis, we present the synthesis, electrochemical properties and photoinduced electron transfer processes of three novel zinc(II)-gold(III) bis(porphyrin) dyads [ZnII(P)-AuIII(P)]+. Time-resolved spectroscopic studies indicate ultrafast dynamics (kET1 > 10^10 s-1) after visible light excitation finally yielding a charge-shifted state [ZnII(P•+)-AuII(P)]+ featuring a gold(II) centre. The lifetime of this excited state is quite long thanks to a comparably slow charge recombination (kBET2 = 3x10^8 s-1). Read More

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http://dx.doi.org/10.1002/chem.201900050DOI Listing
February 2019
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Biochar alleviates fluoride toxicity and oxidative stress in safflower (Carthamus tinctorius L.) seedlings.

Chemosphere 2019 Feb 14;223:406-415. Epub 2019 Feb 14.

Department of Plant Eco-physiology, Faculty of Agriculture, University of Tabriz, Tabriz, Iran. Electronic address:

An original research was laid out as factorial to evaluate the possible effects of biochar (0, 25 and 50 g kg soil) on mitigating fluoride toxicity (non-contamination, 100, 200, 400 and 800 mg NaF kg soil) in safflower seedlings. Increasing fluoride toxicity up to 200 mg NaF kg soil did not decrease the safflower growth. However, the growth of plants under 400 and 800 mg NaF kg was reduced by enhancing soluble fluoride concentration in the soil. Read More

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http://dx.doi.org/10.1016/j.chemosphere.2019.02.087DOI Listing
February 2019

Characteristics of one-year observation of VOCs, NOx, and O at an urban site in Wuhan, China.

J Environ Sci (China) 2019 May 17;79:297-310. Epub 2018 Dec 17.

Beijing Municipal Environmental Monitoring Center, 100048 Beijing, ,China.

A continuous online observation of ozone and its precursors (NOx, VOCs) was carried out in central urban Wuhan from September 2016 to August 2017. The concentration levels of ozone, NOx, VOCs and their variations in urban Wuhan were analyzed, as well as effects of VOCs on ozone photochemical generation and the main controlling factors for ozone production. During the observation period, the average concentrations of ozone and NOx in Wuhan was 22. Read More

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http://dx.doi.org/10.1016/j.jes.2018.12.002DOI Listing

The levels, sources and reactivity of volatile organic compounds in a typical urban area of Northeast China.

J Environ Sci (China) 2019 May 30;79:121-134. Epub 2018 Nov 30.

Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; Center for Excellence in Regional Atmospheric Environment, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen 361021, China; University of Chinese Academy of Sciences, Beijing 100049, China. Electronic address:

Air concentrations of volatile organic compounds (VOCs) were continually measured at a monitoring site in Shenyang from 20 August to 16 September 2017. The average concentrations of alkanes, alkenes, aromatics and carbonyls were 28.54, 6. Read More

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http://dx.doi.org/10.1016/j.jes.2018.11.015DOI Listing

Sources of methacrolein and methyl vinyl ketone and their contributions to methylglyoxal and formaldehyde at a receptor site in Pearl River Delta.

J Environ Sci (China) 2019 May 17;79:1-10. Epub 2018 Dec 17.

Institute for Environmental and Climate Research, Jinan University, Guangzhou, China. Electronic address:

Methacrolein (MACR) and methyl vinyl ketone (MVK) are two major intermediate products from the photochemical oxidation of isoprene, the most important biogenic volatile organic compound. In addition, MACR and MVK have primary emissions. Investigating the sources and evolution of MACR and MVK could provide helpful information for the oxidative capacity of the atmosphere. Read More

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http://dx.doi.org/10.1016/j.jes.2018.12.001DOI Listing

Sources and selection of snow-specific microbial communities in a Greenlandic sea ice snow cover.

Sci Rep 2019 Feb 19;9(1):2290. Epub 2019 Feb 19.

Environmental Microbial Genomics, Laboratoire Ampère, CNRS, École Centrale de Lyon, Écully, France.

Sea ice and its snow cover are critical for global processes including climate regulation and biogeochemical cycles. Despite an increase in studies focused on snow microorganisms, the ecology of snow inhabitants remains unclear. In this study, we investigated sources and selection of a snowpack-specific microbial community by comparing metagenomes from samples collected in a Greenlandic fjord within a vertical profile including atmosphere, snowpack with four distinct layers of snow, sea ice brine and seawater. Read More

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http://dx.doi.org/10.1038/s41598-019-38744-yDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6381142PMC
February 2019

Publisher Correction: Online photochemical derivatization enables comprehensive mass spectrometric analysis of unsaturated phospholipid isomers.

Nat Commun 2019 Feb 19;10(1):918. Epub 2019 Feb 19.

MOE Key Laboratory of Bioorganic Phosphorus Chemistry & Chemical Biology, Department of Chemistry and State Key Laboratory of Precision Measurement Technology and Instruments, Department of Precision Instrument, Tsinghua University, Beijing 100084, China.

The original version of this Article contained an error in Fig. 2f, in which the phospholipid was incorrectly labelled 'PE' rather than the correct 'PC'. This has now been corrected in the PDF and HTML versions of the Article. Read More

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http://dx.doi.org/10.1038/s41467-019-08907-6DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6381096PMC
February 2019

PtNi bimetallic nanoparticles loaded MoS nanosheets: Preparation and electrochemical sensing application for the detection of dopamine and uric acid.

Anal Chim Acta 2019 May 21;1055:17-25. Epub 2018 Dec 21.

Tianjin Key Laboratory of Organic Solar Cells and Photochemical Conversion, School of Chemistry & Chemical Engineering, Tianjin University of Technology, Tianjin, 300384, PR China. Electronic address:

Composite nanomaterials are particularly useful and offer many excellent opportunities for electrochemical sensing application. Depending on the high catalytic activity of bimetallic nanoparticles, the large specific surface area, abundant active edges and co-catalytic function of MoS nanosheets, we, for the first time, prepared a novel PtNi bimetallic nanoparticles loaded MoS nanosheets (PtNi@MoS) hybrid material by a co-reduction method for the electrochemical sensing application. The nanocomposite is characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD), energy dispersive spectroscopy (EDS) and X-ray photoelectron spectroscopy (XPS), and then casted on a bare glassy carbon electrode (GCE) to fabricate an electrochemical sensor (PtNi@MoS/GCE). Read More

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http://dx.doi.org/10.1016/j.aca.2018.12.025DOI Listing

Interaction of aminophylline with photoilluminated vitamin B2 leads to ROS mediated macromolecular damage and cell death in benzopyrene induced mice lung carcinoma.

Chem Biol Interact 2019 Feb 15. Epub 2019 Feb 15.

Department of Biochemistry, Faculty of Life Sciences, AMU, India. Electronic address:

Riboflavin (Rf) or vitamin B₂ is a known photosensitizer whose photophysical and photochemical properties are well established. Aminophylline (Am) is a phosphodiesterase inhibitor and is currently used as a bronchodilator. Although there are several reports of haemolytic and proteolytic interaction of photoilluminated riboflavin with aminophylline, the cytotoxicity of this system against malignant tissue is not well defined and fully unravelled. Read More

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http://dx.doi.org/10.1016/j.cbi.2019.02.003DOI Listing
February 2019

The Dual Role of Benzophenone in Visible-Light/Nickel Photoredox-Catalyzed C-H Arylations: Hydrogen-Atom Transfer and Energy Transfer.

Angew Chem Int Ed Engl 2019 Feb 18. Epub 2019 Feb 18.

Institute of Organic Chemistry, RWTH Aachen University, Landoltweg 1, 52074, Aachen, Germany.

A dual catalytic protocol for the direct arylation of non-activated C(sp )-H bonds has been developed. Upon photochemical excitation, the excited triplet state of a diaryl ketone photosensitizer abstracts a hydrogen atom from an aliphatic C-H bond. This inherent reactivity was exploited for the generation of benzylic radicals which subsequently enter a nickel catalytic cycle, accomplishing the benzylic arylation. Read More

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http://dx.doi.org/10.1002/anie.201901327DOI Listing
February 2019

Chemical and photochemical DNA "gears" reversibly control stiffness, shape-memory, self-healing and controlled release properties of polyacrylamide hydrogels.

Chem Sci 2019 Jan 31;10(4):1008-1016. Epub 2018 Oct 31.

Institute of Chemistry , The Center for Nanoscience and Nanotechnology , The Hebrew University of Jerusalem , Jerusalem , 91904 , Israel . Email: ; ; Tel: +972-2-6585272.

A new class of stimuli-responsive DNA-based polyacrylamide hydrogels is described. They consist of glucosamine-boronate ester-crosslinked polyacrylamide chains being cooperatively bridged by stimuli-responsive nucleic acids. The triggered closure and dissociation of the stimuli-responsive units lead to switchable stiffness properties of the hydrogel. Read More

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http://dx.doi.org/10.1039/c8sc04292fDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6346408PMC
January 2019

Melatonin Improved Waterlogging Tolerance in Alfalfa () by Reprogramming Polyamine and Ethylene Metabolism.

Front Plant Sci 2019 1;10:44. Epub 2019 Feb 1.

Department of Pratacultural Sciences, College of Agriculture, Hunan Agricultural University, Changsha, China.

Melatonin (MT), polyamines (PAs), and ethylene have been suggested to play key roles in plant growth and development in response to environmental abiotic stresses. However, the effect of melatonin on polyamine and ethylene metabolism under waterlogging stress has rarely been elucidated. The main purpose of this study was to investigate the effect of melatonin pretreatment on waterlogging stress in alfalfa. Read More

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http://dx.doi.org/10.3389/fpls.2019.00044DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6367245PMC
February 2019

First synthesis and characterisation of CH4@C60.

Angew Chem Int Ed Engl 2019 Feb 18. Epub 2019 Feb 18.

University of Southampton, School of Chemistry, Highfield, SO17 1BJ, Southampton, UNITED KINGDOM.

The endohedral fullerene CH4@C60, in which each C60 fullerene cage encapsulates a single methane molecule, has been synthesised for the first time. The key orifice contraction step, a photochemical desulfinylation of an open fullerene, was successfully completed, even though it is significantly inhibited by the presence of the endohedral molecule. The 13C NMR resonance for the cage nuclei in CH4@C60 is deshielded by Δδ = +0. Read More

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http://dx.doi.org/10.1002/anie.201900983DOI Listing
February 2019

Activation and Photoinduced Release of Alkynes on a Biomimetic Tungsten Center: The Photochemical Behavior of the W-S-Phoz System.

Chemistry 2019 Feb 18. Epub 2019 Feb 18.

Institute of Chemistry, University of Graz, Schubertstrasse 1, 8010, Graz, Austria.

The synthesis and structural determination of four tungsten alkyne complexes coordinated by the bio-inspired S,N-donor ligand 2-(4',4'-dimethyloxazoline-2'-yl)thiophenolate (S-Phoz) is presented. A previously established protocol that involved the reaction of the respective alkyne with the bis-carbonyl precursor [W(CO) (S-Phoz) ] was used for the complexes [W(CO)(C R )(S-Phoz) ] (R=H, 1 a; Me, 1 b; Ph, 1 c). Oxidation with pyridine-N-oxide gave the corresponding W-oxo species [WO(C R )(S-Phoz) ] (R=H, 2 a; Me, 2 b; Ph, 2 c). Read More

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http://dx.doi.org/10.1002/chem.201805665DOI Listing
February 2019

Seasonal mobility of antimony in sediment-water systems in algae- and macrophyte-dominated zones of Lake Taihu (China).

Chemosphere 2019 Feb 5;223:108-116. Epub 2019 Feb 5.

International Network for Environment and Health, School of Geography and Archaeology & Ryan Institute, National University of Ireland, Galway, Ireland.

Differences in trophic status can lead to different water quality and sediment geochemistry characteristics, influencing antimony (Sb) mobility in sediments and its release into the water column. In this study, seasonal sampling was conducted in algal- and macrophyte-dominated zones of Lake Taihu, China. High-resolution dialysis (HR-Peeper) and diffusive gradients in thin films (DGT) techniques were used to measure soluble Sb and DGT-labile Sb in the sediment-water profiles at a 4 mm vertical resolution. Read More

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http://dx.doi.org/10.1016/j.chemosphere.2019.02.013DOI Listing
February 2019

Effects of graphene oxide on cadmium uptake and photosynthesis performance in wheat seedlings.

Ecotoxicol Environ Saf 2019 Feb 13;173:165-173. Epub 2019 Feb 13.

Agro-Environmental Protection Institute, Ministry of Agriculture of China, Tianjin 300191, China. Electronic address:

Graphene oxide (GO) is extensively used in various fields because of its versatility. The presence of GO in the environment enhances the toxicity of toxicants or pollutants. Cadmium (Cd) and GO pollution is a problem in aquatic environment, which should be solved. Read More

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http://dx.doi.org/10.1016/j.ecoenv.2019.01.093DOI Listing
February 2019
2 Reads

Specificity of the chromophore-binding site in human cone opsins.

J Biol Chem 2019 Feb 15. Epub 2019 Feb 15.

Pharmacology Department, Cleveland Center for Membrane and Structural Biology, School of Medicine,, Case Western Reserve University, United States.

The variable composition of the chromophore-binding pocket in visual receptors is essential for vision. The visual phototransduction starts with the cis-trans isomerization of the retinal chromophore upon absorption of photons. Despite sharing the common 11-cis-retinal chromophore, rod and cone photoreceptors possess distinct photochemical properties. Read More

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http://dx.doi.org/10.1074/jbc.RA119.007587DOI Listing
February 2019

Photochemical Synthesis of Nanosheet Tin Di/Sulfide with Sunlight Response on Water Pollutant Degradation.

Nanomaterials (Basel) 2019 Feb 14;9(2). Epub 2019 Feb 14.

Centre for Nanomaterials Research, Institute of Science, Universiti Teknologi MARA (UiTM), Level 3, Block C, 40450 Shah Alam, Selangor, Malaysia.

The photochemical synthesis of two-dimensional (2D) nanostructured from semiconductor materials is unique and challenging. We report, for the first time, the photochemical synthesis of 2D tin di/sulfide (PS-SnS₂, x = 0 or 1) from thioacetamide (TAA) and tin (IV) chloride in an aqueous system. The synthesized PS-SnS₂ were characterized by X-ray diffraction (XRD), energy dispersive X-ray spectroscopy (EDX), field emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM), a particle size distribution analyzer, X-ray photoelectron spectroscopy (XPS), Fourier-transform infrared spectroscopy (FTIR), thermal analysis, UV⁻Vis diffuse reflectance spectroscopy (DR UV⁻Vis), and photoluminescence (PL) spectroscopy. Read More

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http://dx.doi.org/10.3390/nano9020264DOI Listing
February 2019

Intermittent light and microbial action of mixed endogenous source DOM affects degradation of 17β-estradiol day after day in a relatively deep natural anaerobic aqueous environment.

J Hazard Mater 2019 Feb 6;369:40-49. Epub 2019 Feb 6.

Environmental Engineering and Science Program, Department of Chemical and Environmental Engineering, University of Cincinnati, Cincinnati, OH, 45221, USA. Electronic address:

All kinds of wastewaters containing steroid estrogens (SEs) and mixed endogenous source dissolved organic matter (DOM) enter natural water environments with intermittent illumination where microbial action occurs in a relatively deep natural aqueous environment. The role of mixed endogenous source DOM in SEs' biodegradation and photochemical degradation in such environments was studied using 17β-estradiol (E2) in laboratory experiments under anaerobic conditions. The experimental results show that microbial action can improve the optical properties and electron transfer capability of mixed endogenous source DOM, promoting photodegradation and biodegradation. Read More

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http://dx.doi.org/10.1016/j.jhazmat.2019.02.017DOI Listing
February 2019

Biosynthesis of Providencin: Understanding Photochemical Cyclobutane Formation with Density Functional Theory.

Org Lett 2019 Feb 15. Epub 2019 Feb 15.

Chemistry Research Laboratory , University of Oxford , 12 Mansfield Road , Oxford OX1 3TA , U.K.

The unique structure of furanocembranoid natural product providencin has stimulated biosynthetic hypotheses, especially concerning the formation of its cyclobutanol ring. One such hypothesis involves a photochemically induced Norrish-Yang cyclization in bipinnatin E. We have used computations to assess the feasibility and the stereochemical outcome of this proposed biosynthetic transformation. Read More

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http://pubs.acs.org/doi/10.1021/acs.orglett.8b03838
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http://dx.doi.org/10.1021/acs.orglett.8b03838DOI Listing
February 2019
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Locked-Azobenzene: Testing the Scope of a Unique Photoswitchable Scaffold for Cell Physiology.

ACS Chem Neurosci 2019 Feb 15. Epub 2019 Feb 15.

Department of Neuroscience , Mount Sinai School of Medicine , New York , New York 10029 , United States.

Azobenzenes are the most widely studied photoswitches, and have become popular optical probes for biological systems. The cis configuration is normally metastable, meaning the trans configuration is always thermodynamically favored. The unique exception to this rule is an azobenzene having a two-carbon bridge between ortho positions, substitutions that lock the photoswitch in its cis configuration. Read More

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http://dx.doi.org/10.1021/acschemneuro.8b00734DOI Listing
February 2019
4.362 Impact Factor

Visible-light activated metal catalyst-free vicinal diazidation of olefins with sulfonium iodate(i) species.

Chem Commun (Camb) 2019 Feb 15. Epub 2019 Feb 15.

Department of Chemistry, Malaviya National Institute of Technology, Jaipur-302017, India.

A visible light-induced vicinal diazidation of various alkenes using stable sulfonium bis(acetoxy)iodate(i) and sodium azide as a radical precursor is described. The trimethylsulfonium [bis(azido)iodate(i)] species, intrinsically generated in situ, demonstrated unprecedented reactivity toward C[double bond, length as m-dash]C π bond-promoting selective azidation under photochemical conditions without any photoredox or metal catalyst. The visible-light stimulated diazidation reaction provides a convenient and straightforward approach to highly prevalent vicinal nitrogen scaffolds of myriad therapeutic importance. Read More

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http://dx.doi.org/10.1039/c9cc00007kDOI Listing
February 2019

LHC-like proteins involved in stress responses and biogenesis/repair of the photosynthetic apparatus.

Biochem J 2019 Feb 14;476(3):581-593. Epub 2019 Feb 14.

Department of Biotechnology, University of Verona, 37134 Verona, Italy.

LHC (light-harvesting complex) proteins of plants and algae are known to be involved both in collecting light energy for driving the primary photochemical reactions of photosynthesis and in photoprotection when the absorbed light energy exceeds the capacity of the photosynthetic apparatus. These proteins usually contain three transmembrane (TM) helices which span the thylakoid membranes and bind several chlorophyll, carotenoid and lipid molecules. In addition, the LHC protein family includes LHC-like proteins containing one, two, three or even four TM domains. Read More

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http://dx.doi.org/10.1042/BCJ20180718DOI Listing
February 2019

Photochemical degradation of BPF, BPS and BPZ in aqueous solution: Identification of transformation products and degradation kinetics.

Sci Total Environ 2019 Feb 5;664:595-604. Epub 2019 Feb 5.

Jožef Stefan Institute, Jamova cesta 39, 1000 Ljubljana, Slovenia; International Postgraduate School Jožef Stefan, Jamova cesta 39, 1000 Ljubljana, Slovenia. Electronic address:

Bisphenols (BPs) are industrial chemicals that are used as monomers in the production of polycarbonate plastics and epoxy resins. These compounds can leach into the aqueous environment, where they can potentially have toxic effects. The aim of this study was to assess the photochemical degradation of three common bisphenols: BPF, BPS and BPZ in aqueous solution and determine their degradation kinetics and characterise their transformation products. Read More

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http://dx.doi.org/10.1016/j.scitotenv.2019.02.064DOI Listing
February 2019
2 Reads

Merging Photochemistry with Electrochemistry: Functional Group Tolerant Electrochemical Amination of sp³ C-H Bonds.

Angew Chem Int Ed Engl 2019 Feb 14. Epub 2019 Feb 14.

University of Wisconsin-Madison, Department of Chemistry, 1101 University Avenue, 53706, Madison, UNITED STATES.

Direct amination of sp³ C-H bonds is of broad interest in the realm of C-H functionalization because of the prevalence of nitrogen heterocycles and amines in pharmaceuticals and natural products. Here, we report a combined electrochemical/photochemical method for dehydrogenative C(sp³)-H/N-H coupling that exhibits good reactivity with both sp² and sp³ N-H bonds. The results show how use of iodide as an electrochemical mediator, in combination with light-induced cleavage of intermediate N-I bonds, enables the electrochemical process to proceed at low electrode potentials. Read More

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http://dx.doi.org/10.1002/anie.201813960DOI Listing
February 2019

Aerobic Oxidation of in Situ Generated Cyanine Dyes Leading to DNA Damage.

Org Lett 2019 Feb 14. Epub 2019 Feb 14.

Center for Photochemical Sciences and Chemistry Department , Bowling Green State University , Bowling Green , Ohio 43403 , United States.

DNA damage induced by noncatalytic aerobic oxidation of pyridinocyanine dyes is described. The dyes are generated in situ during spontaneous oxidations of tetrakis- and bis( N-methylpyridin-4-ium)alkane salts. The mechanism of aerobic oxidation of the latter compound is proposed, and a rare direct catalyst-free transition from saturated alkane to a gem-diol is demonstrated. Read More

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http://pubs.acs.org/doi/10.1021/acs.orglett.9b00194
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http://dx.doi.org/10.1021/acs.orglett.9b00194DOI Listing
February 2019
2 Reads

Supramolecular Gel as the Template for Catalysis, Inorganic Superstructure, and Pharmaceutical Crystallization.

Authors:
Arnab Dawn

Int J Mol Sci 2019 Feb 12;20(3). Epub 2019 Feb 12.

James Winkle College of Pharmacy, University of Cincinnati, 231 Albert Sabin Way, Cincinnati, OH 45267-0514, USA.

A supramolecular gel is a fascinating combination of flexibility and orderliness. While the supramolecular nature of crosslinking contributes towards the adaptivity and the reversibility of the system, orderliness at the molecular level amplifies the functional output and induces extraordinary selectivity into the system. Therefore, use of supramolecular gels as the soft template is an emerging area of research, which includes but not limited to catalysis of a chemical or a photochemical process, transcription of gel property to a substrate, or even controlling the nucleation of drug molecules. Read More

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http://dx.doi.org/10.3390/ijms20030781DOI Listing
February 2019

Photobleaching Comparison of R-Phycoerythrin-Streptavidin and Streptavidin-Alexa Fluor 568 in a Breast Cancer Cell Line.

Monoclon Antib Immunodiagn Immunother 2019 Feb 13. Epub 2019 Feb 13.

1 Nanotechnology Research Center, Faculty of Pharmacy, Tehran University of Medical Sciences, Tehran, Iran.

Fluorescent dyes are excited by light and emit light at a longer wavelength. Photobleaching is one the most important obstacles in fluorescent image capturing. Photochemical alteration of a fluorescent dye caused by several excitation/emission cycles results in a fluorophore to be unable to emit light. Read More

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http://dx.doi.org/10.1089/mab.2018.0046DOI Listing
February 2019

Triplet-State Photochemistry of Dissolved Organic Matter: Triplet-State Energy Distribution and Surface Electric Charge Conditions.

Environ Sci Technol 2019 Feb 18. Epub 2019 Feb 18.

Department of Environmental Science & Engineering , Fudan University , Shanghai 200433 , P. R. China.

Excited triplet states of chromophoric dissolved organic matter (CDOM*) are highly reactive species in sunlit surface waters and play a critical role in reactive oxygen species (ROS) formation and pollutant attenuation. In the present study, a series of chemical probes, including sorbic acid, sorbic alcohol, sorbic amine, trimethylphenol, and furfuryl alcohol, were employed to quantitatively determine CDOM* and O in various organic matters. Using a high concentration of sorbic alcohol as high-energy triplet states quencher, CDOM* can be first distinguished as high-energy triplet states (>250 kJ mol) and low-energy triplet states (<250 kJ mol). Read More

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http://dx.doi.org/10.1021/acs.est.8b06574DOI Listing
February 2019

Identification of Flavin Mononucleotide as Cell-Active Artificial N6-Methyladenosine RNA Demethylase.

Angew Chem Int Ed Engl 2019 Feb 12. Epub 2019 Feb 12.

Institute of Chemistry Chinese Academy of Sciences, CAS Key Laboratory of Molecular Recognition and Function, No. 2 Zhongguancun North 1st Street, P.O. Box 2709-24, 100190, Beijing, CHINA.

N6-Methyladenosine (m6A) represents a common and highly dynamic modification in eukaryotic RNA that affects various cellular pathways. Natural dioxygenases such as FTO and ALKBH5 are enzymes that demethylate m6A residues in mRNA. Herein, the first identification of a small-molecule modulator that functions as an artificial m6A demethylase was reported. Read More

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http://dx.doi.org/10.1002/anie.201900901DOI Listing
February 2019

Secretome profiling of heterotypic spheroids suggests a role of fibroblasts in HIF-1 pathway modulation and colorectal cancer photodynamic resistance.

Cell Oncol (Dordr) 2019 Feb 12. Epub 2019 Feb 12.

Departamento de Biología Molecular, Facultad de Ciencias Exactas Físico-Químicas y Naturales, Universidad Nacional de Río Cuarto, 5800, Río Cuarto, Córdoba, Argentina.

Purpose: Previous analyses of the tumor microenvironment (TME) have resulted in a concept that tumor progression may depend on interactions between cancer cells and its surrounding stroma. An important aspect of these interactions is the ability of cancer cells to modulate stroma behavior, and vice versa, through the action of a variety of soluble mediators. Here, we aimed to identify soluble factors present in the TME of colorectal cancer cells that may affect relevant pathways through secretome profiling. Read More

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http://dx.doi.org/10.1007/s13402-018-00418-8DOI Listing
February 2019

Two-State Three-Mode Parametrization of the Force Field of a Retinal Chromophore Model.

J Phys Chem A 2019 Feb 12. Epub 2019 Feb 12.

In recent years the potential energy surfaces of the penta-2,4-dieniminium cation have been investigated using several electronic structure methods. The resulting pool of geometrical, electronic and energy data, provides the basis for the construction of a topographically correct analytical model of the molecule force field and, therefore, for a better understanding of these systems which include the chromophore of visual pigments. In the present contribution, we report the construction of such a model for regions of the force field driving the photochemical and thermal isomerization of the central double bound of the cation. Read More

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http://dx.doi.org/10.1021/acs.jpca.8b10010DOI Listing
February 2019

Femtosecond Photon-Mediated Plasma Enhances Photosynthesis of Plasmonic Nanostructures and Their SERS Applications.

Small 2019 Feb 12:e1804899. Epub 2019 Feb 12.

Department of Electrical and Computer Engineering, University of Nebraska-Lincoln, Lincoln, NE, 68588-0511, USA.

Laser ablation in liquid has proven to be a universal and green method to synthesize nanocrystals and fabricate functional nanostructures. This study demonstrates the superiority of femtosecond laser-mediated plasma in enhancing photoredox of metal cations for controllable fabrication of plasmonic nanostructures in liquid. Through employing upstream high energetic plasma during laser-induced microexplosions, single/three-electron photoreduction of metallic cations can readily occur without chemical reductants or capping agents. Read More

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http://dx.doi.org/10.1002/smll.201804899DOI Listing
February 2019
1 Read

A Redox Active Nickel Complex that Acts as an Electron Mediator in Photochemical Giese Reactions.

Angew Chem Int Ed Engl 2019 Feb 12. Epub 2019 Feb 12.

Institute of Chemical Research of Catalonia (ICIQ), ICIQ, Av. Països Catalans 16, 43007, Tarragona, SPAIN.

We report a simple protocol for the photochemical Giese addition of C(sp3)-centered radicals to a variety of electron-poor olefins. The chemistry does not require external photoredox catalysts. Instead, it harnesses the excited-state reactivity of 4-alkyl-1,4-dihydropyridines (4-alkyl-DHPs) to generate alkyl radicals. Read More

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http://dx.doi.org/10.1002/anie.201814497DOI Listing
February 2019
1 Read

Mitochondria targeted and NADH triggered photodynamic activity of chloromethyl modified Ru(ii) complexes under hypoxic conditions.

Chem Commun (Camb) 2019 Feb 12. Epub 2019 Feb 12.

Key Laboratory of Photochemical Conversion and Optoelectronic Materials, Technical Institute of Physics and Chemistry, Chinese Academy of Sciences, Beijing 100190, P. R. China.

Three chloromethyl-modified Ru(ii) complexes were designed and synthesized as mitochondria targeting photosensitizers, which can generate carbon radicals in the presence of NADH under visible light irradiation, cause DNA cleavage and covalent binding in Ar-saturated solutions, and lead to apoptosis of human ovarian carcinoma SKOV-3 cells under hypoxic conditions (3% O2), demonstrating a new mode of type I mechanism to overcome the limitation of hypoxia in photodynamic therapy (PDT). Read More

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http://dx.doi.org/10.1039/c8cc09186bDOI Listing
February 2019

Investigating Dynamic Molecular Events in Melanoma Cell Nucleus During Photodynamic Therapy by SERS.

Front Chem 2018 28;6:665. Epub 2019 Jan 28.

State Key Laboratory of Supramolecular Structure and Materials, Institute of Theoretical Chemistry, Jilin University, Changchun, China.

Photodynamic therapy (PDT) involves the uptake of photosensitizers by cancer cells and the irradiation of a light with a specific wavelength to trigger a series of photochemical reactions based on the generation of reactive oxygen, leading to cancer cell death. PDT has been widely used in various fields of biomedicine. However, the molecular events of the cancer cell nucleus during the PDT process are still unclear. Read More

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http://dx.doi.org/10.3389/fchem.2018.00665DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6360157PMC
January 2019
1 Read

Preparation of photosensitive diazotized poly (vinyl alcohol-b-styrene) covalent capillary coatings for capillary electrophoresis separation of proteins.

J Chromatogr A 2019 Feb 4. Epub 2019 Feb 4.

Institute of Biomedical Materials and Engineering, College of Chemistry and Chemical Engineering, College of Materials Science and Engineering, Qingdao University, Qingdao, 266071, China; Laboratory for New Fiber Materials and Modern Textile, Growing Base for State Key Laboratory, Qingdao University, Qingdao, 266071, China. Electronic address:

In this paper, we have developed a novel method for the preparation of covalently connected capillary coatings in which diazotized poly (vinyl alcohol-b-styrene) (diazo-P(VA-b-St)) was used as a photosensitive coating agent. Firstly, the diazo-P(VA-b-St) coating was self-assembled on the inner surface of the capillary, and then irradiated by ultraviolet (UV) light to convert the ionic bonding into covalent bonding through the unique photochemical reaction of diazo groups. The covalently connected coatings inhibited the protein adsorption on the inner surface of the capillary, as a result, the baseline protein separation of ribonuclease A (RNase A), lysozyme (Lyz) and bovine serum albumin (BSA) were attained by utilizing the capillary electrophoresis (CE). Read More

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http://dx.doi.org/10.1016/j.chroma.2019.02.004DOI Listing
February 2019
4.169 Impact Factor

Overcoming limitations in photochemical UVC/HO systems using a mili-photoreactor (NETmix): Oxytetracycline oxidation.

Sci Total Environ 2019 Apr 6;660:982-992. Epub 2019 Jan 6.

Laboratory of Separation and Reaction Engineering, Laboratory of Catalysis and Materials (LSRE-LCM), Department of Chemical Engineering, Faculty of Engineering, University of Porto, Rua Dr. Roberto Frias, 4200-465, Porto, Portugal. Electronic address:

This study focuses on the intensification of a photochemical UVC/HO system using a mili-photoreactor (NETmix) for a better and faster elimination of oxytetracycline (OTC) from urban wastewater. This mili-photoreactor comprises a network of small cylindrical chambers and prismatic transport channels sealed by a UVC transparent quartz slab allowing unique properties. Since light has a profound effect on the photochemical process, UVC photons distribution over the reaction medium was investigated using a multiple UVC lamp design (4, 6 or 11 W) allocated in parallel or perpendicular to the solution movement. Read More

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http://dx.doi.org/10.1016/j.scitotenv.2019.01.012DOI Listing