keyword
MENU ▼
Read by QxMD icon Read
search

constant light

keyword
https://www.readbyqxmd.com/read/28641143/spectroscopic-and-thermodynamic-studies-of-light-harvesting-perylenediimide-derivative-zinc-porphyrin-complex-in-aqueous-media
#1
Ahmed El-Refaey, Shaban Y Shaban, Maged El-Kemary, Mohamed E El-Khouly
Self-assembly of perylene derivative such as N,N'-bis(2(trimethylammonium iodide) ethylene)perylene-3,4,9,10-tetracarboxyldiimide (TAIPDI) can produce one-dimensional form (1D) in an aqueous media. The ability of one-dimensional TAIPDI to form light harvesting complex with water-soluble zinc porphyrin (ZnTPPS4) via the π-π and electrostatic interactions has been described. Owing to electronic interactions between the π-systems, the complex formation is accompanied by pronounced absorption spectral changes in the UV/Vis absorption bands...
June 15, 2017: Spectrochimica Acta. Part A, Molecular and Biomolecular Spectroscopy
https://www.readbyqxmd.com/read/28640625/dust-effects-on-nucleation-kinetics-and-nanoparticle-product-size-distributions-illustrative-case-study-of-a-prototype-ir-0-n-transition-metal-nanoparticle-formation-system
#2
Saim Özkar, Richard G Finke
The question is addressed if dust is kinetically important in the nucleation and growth of Ir(0)n nanoparticles formed from [Bu4N]5Na3(1,5-COD)Ir(I)·P2W15Nb3O62 (hereafter [(COD)Ir·POM](8-)), reduced by H2 in propylene carbonate solvent. Following a concise review of the (often-neglected) literature addressing dust in nucleation phenomena dating back to the late 1800s, the nucleation and growth kinetics of the [(COD)Ir·POM](8-) precatalyst system are examined for the effects of 0.2 μm microfiltration of the solvent and precatalyst solution, of rinsing the glassware with that microfiltered solvent, of silanizing the glass reaction vessel, for the addition of <0...
June 22, 2017: Langmuir: the ACS Journal of Surfaces and Colloids
https://www.readbyqxmd.com/read/28636318/inverse-photonic-glasses-by-packing-bi-disperse-hollow-microspheres-with-uniform-cores
#3
Seung-Hyun Kim, Sofia Magkiriadou, Do Kyung Rhee, Doo Sung Lee, Pil J Yoo, Vinothan N Manoharan, Gi-Ra Yi
A major fabrication challenge is producing disordered photonic materials with angle-independent structural red color. Theoretical work has shown that such color can be produced by fabricating inverse photonic glasses with monodisperse, non-touching voids in a silica matrix. Here we demonstrate a route toward such materials and show that they have angle-independent red color. We first synthesize monodisperse hollow silica particles with precisely controlled shell thickness, then make glassy colloidal structures by mixing two types of hollow particles with the same core size and different shell thicknesses...
June 21, 2017: ACS Applied Materials & Interfaces
https://www.readbyqxmd.com/read/28635282/fining-of-red-wine-monitored-by-multiple-light-scattering
#4
Giovanna Ferrentino, Mohsen Ramezani, Ksenia Morozova, Daniela Hafner, Ulrich Pedri, Konrad Pixner, Matteo Scampicchio
This work describes a new approach based on multiple light scattering to study red wine clarification processes. The whole spectral signal (1933 backscattering points along the length of each sample vial) were fitted by a multivariate kinetic model that was built with a three-step mechanism, implying: 1) adsorption of wine colloids to fining agents; 2) aggregation into larger particles; 3) sedimentation. Each step is characterized by a reaction rate constant. According to the first reaction, the results showed that gelatin was the most efficient fining agent, concerning the main objective, which was the clarification of the wine, and consequently the increase in its limpidity...
June 21, 2017: Journal of Agricultural and Food Chemistry
https://www.readbyqxmd.com/read/28634485/nitrogen-can-alleviate-the-inhibition-of-photosynthesis-caused-by-high-temperature-stress-under-both-steady-state-and-flecked-irradiance
#5
Guanjun Huang, Qiangqiang Zhang, Xinghai Wei, Shaobing Peng, Yong Li
Nitrogen is one of the most important elements for plants and is closely related to photosynthesis. High temperature stress significantly inhibits photosynthesis under both steady-state and flecked irradiance. However, it is not known whether nitrogen can affect the decrease in photosynthesis caused by high temperature, especially under flecked irradiance. In the present study, a pot experiment was conducted under two nitrogen (N) supplies with rice plants, and the steady-state and dynamic photosynthesis rates were measured under 28 and 40°C...
2017: Frontiers in Plant Science
https://www.readbyqxmd.com/read/28634405/shedding-new-light-on-an-old-molecule-quinophthalone-displays-uncommon-n-to-o-excited-state-intramolecular-proton-transfer-esipt-between-photobases
#6
Gi Rim Han, Doyk Hwang, Seunghoon Lee, Jong Woo Lee, Eunhak Lim, Jiyoung Heo, Seong Keun Kim
Excited state dynamics of common yellow dye quinophthalone (QPH) was probed by femtosecond transient absorption spectroscopy. Multi-exponential decay of the excited state and significant change of rate constants upon deuterium substitution indicate that uncommon nitrogen-to-oxygen excited state intramolecular proton transfer (ESIPT) occurs. By performing density functional theory (DFT) and time-dependent density functional theory (TDDFT) calculations, we found that adiabatic surface crossing between the S1 and S2 states takes place in the photoreaction...
June 20, 2017: Scientific Reports
https://www.readbyqxmd.com/read/28633823/sono-synthesis-of-solar-light-responsive-s-n-c-tri-doped-tio2-photo-catalyst-under-optimized-conditions-for-degradation-and-mineralization-of-diclofenac
#7
Sara Ramandi, Mohammad H Entezari, Narjes Ghows
C-N-S-tri doped TiO2 anatase phase was synthesized using a facile, effective and novel sonochemical method at low frequency (20kHz) and at room temperature. Titanium butoxide as the titanium precursor and thiourea as the dopant source were used in the synthesis of the photo-catalyst. The effects of important parameters such as thiourea/Ti molar ratio, ultrasound intensity, sonication time and temperature were studied on the synthesis of tri-doped TiO2. The XPS results confirmed the presence of N, S, and C in the photo-catalyst...
September 2017: Ultrasonics Sonochemistry
https://www.readbyqxmd.com/read/28631620/effectiveness-of-pelvic-lead-blanket-to-reduce-the-doses-to-eye-lens-and-hands-of-interventional-cardiologists-and-assistant-nurses
#8
Włodzimierz Grabowicz, Joanna Karolina Domienik-Andrzejewska, Konrad Masiarek, Tomasz Górnik, Tomasz Grycewicz, Marcin Brodecki, Andrzej Lubiński
The aim of the present study is to analyse quantitatively the potential reduction of the doses to eye lens and the hands of an operator and a nurse by the pelvic lead blanket during coronary angiography (CA) and percutaneous transluminal coronary angioplasty (PTCA) procedures. Thermoluminescent dosimeters (TLDs) were used to assess dose levels to left eye lens and left and right fingers of both physician and nurses during single procedures performed with or without lead blanket. The measurements were carried out in one medical centre and include dosimetric data from100 procedures...
June 20, 2017: Journal of Radiological Protection: Official Journal of the Society for Radiological Protection
https://www.readbyqxmd.com/read/28630449/effect-of-dna-sequence-of-fab-fragment-on-yield-characteristics-and-cell-growth-of-e-coli
#9
Antti Kulmala, Tuomas Huovinen, Urpo Lamminmäki
Codon usage is one of the factors influencing recombinant protein expression. We were interested in the codon usage of an antibody Fab fragment gene exhibiting extreme toxicity in the E. coli host. The toxic synthetic human Fab gene contained domains optimized by the "one amino acid-one codon" method. We redesigned five segments of the Fab gene with a "codon harmonization" method described by Angov et al. and studied the effects of these changes on cell viability, Fab yield and display on filamentous phage using different vectors and bacterial strains...
June 19, 2017: Scientific Reports
https://www.readbyqxmd.com/read/28629072/photodynamic-effect-of-light-harvesting-long-lived-triplet-excited-state-ruthenium-ii-polyimine-coumarin-complexes-dna-binding-photocleavage-and-anticancer-studies
#10
Raju Nomula, Xueyan Wu, Jianzhang Zhao, Nagegownivari R Munirathnam
Two coumarin based Ru(II)-polyimine complexes (Ru-1 and Ru-2) showing intense absorption of visible light and long-lived triplet excited states (~12-15μs) were used for study of the interaction with DNA. The binding of the complexes with CT-DNA were studied by UV-vis, fluorescence and time-resolved nanosecond transient absorption (ns-TA) spectroscopy. The results suggesting that the complexes interact with CT-DNA by intercalation mode of binding, showing the binding constants (Kb) 6.47×10(4) for Ru-1 and 5...
October 1, 2017: Materials Science & Engineering. C, Materials for Biological Applications
https://www.readbyqxmd.com/read/28626557/electrostatically-driven-resonance-energy-transfer-in-cationic-biocompatible-indium-phosphide-quantum-dots
#11
Gayathri Devatha, Soumendu Roy, Anish Rao, Abhik Mallick, Sudipta Basu, Pramod P Pillai
Indium Phosphide Quantum Dots (InP QDs) have emerged as an alternative to toxic metal ion based QDs in nanobiotechnology. The ability to generate cationic surface charge, without compromising stability and biocompatibility, is essential in realizing the full potential of InP QDs in biological applications. We have addressed this challenge by developing a place exchange protocol for the preparation of cationic InP/ZnS QDs. The quaternary ammonium group provides the much required permanent positive charge and stability to InP/ZnS QDs in biofluids...
May 1, 2017: Chemical Science
https://www.readbyqxmd.com/read/28623599/energetics-and-reactivity-of-small-beryllium-deuterides
#12
Ivan Sukuba, Alexander Kaiser, Stefan E Huber, Jan Urban, Michael Probst
Enthalpies and free energies of reaction for small neutral and charged beryllium deuterides BeD, BeD2, and BeD3 that have been calculated are reported for a temperature range of 0 K to 1000 K. We discuss probable dissociation channels and possible ways of producing BeD by localizing the relevant transition states and by calculating corresponding rate constants. BeD and BeD(+) are found to be the most stable ones among the considered compounds. BeD2 and [Formula: see text] are more likely to decompose into Be(0,+) + D2 than into BeD(0,+) + D...
July 2017: Journal of Molecular Modeling
https://www.readbyqxmd.com/read/28623226/entraining-to-the-polar-day-circadian-rhythms-in-arctic-ground-squirrels
#13
Cory T Williams, Brian M Barnes, Lily Yan, C Loren Buck
Circadian systems are principally entrained to 24h light/dark cycles, but this cue is seasonally absent in polar environments. Although some resident polar vertebrates have weak circadian clocks and are seasonally arrhythmic, the arctic ground squirrel (AGS) maintains daily rhythms of physiology and behavior throughout the summer, which includes six weeks of constant daylight. Here, we show that persistent daily rhythms in AGS are maintained through a circadian system that readily entrains to the polar day yet remains insensitive to entrainment by rapid light-dark transitions, which AGS generate naturally due to their semi-fossorial behavior...
June 16, 2017: Journal of Experimental Biology
https://www.readbyqxmd.com/read/28622053/importance-of-sandy-bottoms-in-coral-reefs-to-the-oscillation-of-daily-rhythms-in-the-tropical-wrasse-halichoeres-trimaculatus
#14
Hitomi Ito-Takeuchi, Kai Takahashi, Selma Bouchekioua, Chihiro Yamauchi, Yuki Takeuchi, Sung-Pyo Hur, Young-Don Lee, Akihiro Takemura
Most wrasse species swim during the day and bury themselves in the sandy bottoms of shallow reefs at night. This study aimed to evaluate the importance of sandy bottoms to the day-active/night-inactive rhythmicity of the tropical wrasse Halichoeres trimaculatus. Actogram analysis revealed that fish were active during the photophase and inactive during the scotophase in aquariums with both sandy and bare bottoms. When fish were kept in aquariums with bare bottoms, rhythmicity was maintained under constant dark conditions (DD) but became obscured under constant light conditions (LL), suggesting that a day-active/night-inactive rhythmicity is regulated by the circadian system...
June 16, 2017: Chronobiology International
https://www.readbyqxmd.com/read/28621997/cooling-a-harmonic-oscillator-by-optomechanical-modification-of-its-bath
#15
Xunnong Xu, Thomas Purdy, Jacob M Taylor
Optomechanical systems show tremendous promise for the high-sensitivity sensing of forces and modification of mechanical properties via light. For example, similar to neutral atoms and trapped ions, laser cooling of mechanical motion by radiation pressure can take single mechanical modes to their ground state. Conventional optomechanical cooling is able to introduce an additional damping channel to mechanical motion while keeping its thermal noise at the same level, and, as a consequence, the effective temperature of the mechanical mode is lowered...
June 2, 2017: Physical Review Letters
https://www.readbyqxmd.com/read/28621403/mixed-metal-oxides-of-the-type-coxzn1-xfe2o4-as-photocatalysts-for-malachite-green-degradation-under-uv-light-irradiation
#16
Martin Tzvetkov, Maria Milanova, Zara Cherkezova-Zheleva, Ivanka Spassova, Evgenia Valcheva, Joana Zaharieva, Mitov Ivan
A combination of thermal and mechanical (high energy ball milling) treatment was applied in an attempt to obtain polycrystalline mixed metal binary and ternary oxides of the type CoxZn1-xFe2O4 (x = 0; 0.25; 0.5; 0.75; 1). The synthetic procedure used successfully produced single-phased, homogeneous ZnFe2O4, CoFe2O4, and Co0.75Zn0.25Fe2O4, as well as mixed oxides, whose composition depended both on the duration of the high energy ball milling and the ratio Zn(II)/Co(II). The formation of spinel-like structures was proved by XRD, Mössbauer spectroscopy and Raman spectroscopy...
June 2017: Acta Chimica Slovenica
https://www.readbyqxmd.com/read/28619035/an-evolutionary-optimization-of-a-rhodopsin-based-phototrophic-metabolism-in-escherichia-coli
#17
Hyun Aaron Kim, Hyun Ju Kim, Jihoon Park, Ah Reum Choi, Kyoo Heo, Haeyoung Jeong, Kwang-Hwan Jung, Yeong-Jae Seok, Pil Kim, Sang Jun Lee
BACKGROUND: The expression of the Gloeobacter rhodopsin (GR) in a chemotrophic Escherichia coli enables the light-driven phototrophic energy generation. Adaptive laboratory evolution has been used for acquiring desired phenotype of microbial cells and for the elucidation of basic mechanism of molecular evolution. To develop an optimized strain for the artificially acquired phototrophic metabolism, an ancestral E. coli expressing GR was adaptively evolved in a chemostat reactor with constant illumination and limited glucose conditions...
June 15, 2017: Microbial Cell Factories
https://www.readbyqxmd.com/read/28618549/breakdown-of-the-stokes-einstein-relation-in-pure-lennard-jones-fluids-from-gas-to-liquid-via-supercritical-states
#18
Norikazu Ohtori, Shohei Miyamoto, Yoshiki Ishii
We have examined the conditions under which the breakdown of the Stokes-Einstein (SE) relation occurs in pure Lennard-Jones (LJ) fluids over a wide range of temperatures and packing fractions beyond the critical point. To this end, the temperature and packing-fraction dependence of the self-diffusion coefficient, D, and the shear viscosity, η_{sv}, were evaluated for Xe using molecular dynamics calculations with the Green-Kubo formula. The results showed good agreement with the experimental values. The breakdown was determined in light of the SE equation which we have recently derived for pure LJ liquids: Dη_{sv}=(k_{B}T/2π)(N/V)^{1/3}, where k_{B} is the Boltzmann constant, T is the temperature, and N is the particle number included in the system volume V...
May 2017: Physical Review. E
https://www.readbyqxmd.com/read/28617195/light-and-clock-control-of-genes-involved-in-detoxification
#19
G Carmona-Antoñanzas, M Santi, H Migaud, L M Vera
Circadian regulation of hepatic detoxification seems to be amongst the key roles of the biological clock. The liver is the major site for biotransformation, and in mammals, it contains several clock-controlled transcription factors such as proline and acidic amino acid-rich basic leucine zipper proteins (PAR bZIP) and basic-helix-loop-helix Per-Arnt-Sim (bHLH-PAS) family that act as circadian regulators of detoxification genes. This investigation explored the existence of daily and circadian expression of transcription factors involved in detoxification, as well as the temporal profile of a set of their target genes in zebrafish liver...
June 15, 2017: Chronobiology International
https://www.readbyqxmd.com/read/28612754/carrier-transport-and-emission-efficiency-in-ingan-quantum-dot-based-light-emitting-diodes
#20
Daniele Barettin, Matthias Auf der Maur, Aldo di Carlo, Alessandro Pecchia, Andrei F Tsatsulnikov, Wsevolod V Lundin, Alexei V Sakharov, Andrei E Nikolaev, Maxim Korytov, Nikolay Cherkashin, Martin J Hÿtch, Sergey Yu Karpov
We present a study of blue III-nitride light-emitting diodes (LEDs) with multiple quantum well (MQW) and quantum dot (QD) active regions (ARs), comparing experimental and theoretical results. The LED samples were grown by metalorganic vapor phase epitaxy, utilizing growth interruption in the hydrogen/nitrogen atmosphere and variable reactor pressure to control the AR microstructure. Realistic configuration of the QD AR implied in simulations was directly extracted from HRTEM characterization of the grown QD-based structures...
July 7, 2017: Nanotechnology
keyword
keyword
88603
1
2
Fetch more papers »
Fetching more papers... Fetching...
Read by QxMD. Sign in or create an account to discover new knowledge that matter to you.
Remove bar
Read by QxMD icon Read
×

Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"