scholarly journals Experimental Measurement of Sharp THz Absorption Signatures from Nucleic Acid Solutions in Nanofluidic Channels

2021 ◽  
Vol 11 (24) ◽  
pp. 11827
Author(s):  
Elliott R. Brown ◽  
Edgar A. Mendoza
Keyword(s):  
Nucleic Acid ◽  
Experimental Measurement ◽  
Room Temperature ◽  
Persistence Length ◽  
Acid Solutions ◽  
Nanofluidic Channels ◽  
Molecular Length ◽  
Fused Quartz ◽  
Thz Absorption ◽  
Quartz Substrates

We report on the room-temperature experimental measurement of THz absorption signatures in aqueous, double-stranded nucleic acid solutions confined to the submicron silica channels on fused quartz substrates using THz frequency-domain (photomixing) spectroscopy. Three sharp (i.e., strong and narrow) signatures, ~10–20 GHz FWHM, are observed in the shortest base pair sample—small interfering, double-stranded (ds) RNA—in the range of 800 GHz to 1.1 THz. Three similar signatures are also observed in a 50-bp dsDNA ladder sample. For a 1-kbp dsDNA ladder sample, the three are still evident, but are broadened and weakened. For a 48.5-kbp sample (λ-DNA), no prominent signatures are observed, but rather a quasi-sinusoidal transmittance spectrum consistent with a substrate etalon effect. The division between sharp signatures and no signatures is consistent with the molecular length being shorter or longer than the persistence length.

Effect of Growth Atmosphere on the Structural, Optical and Magnetic Properties of Fe-Doped In2O3 Films

2013 ◽  
Vol 668 ◽  
pp. 757-761
Author(s):  
Peng Fei Xing ◽  
Shao Hua Sun ◽  
Ping Wu
Keyword(s):  
Room Temperature ◽  
Oxygen Vacancies ◽  
Optical Band Gap ◽  
Room Temperature Ferromagnetism ◽  
N2 Atmosphere ◽  
Growth Atmosphere ◽  
Fused Quartz ◽  
Optical And Magnetic Properties ◽  
Acceptor Defect ◽  
Quartz Substrates

Room temperature ferromagnetism was observed in Fe-doped In2O3 films deposited on fused quartz substrates by radiofrequency magnetron sputtering in N2 and O2 atmosphere, respectively. Results show that with increasing the O2 and N2 flux, the lattice constant increases, the optical band gap decreases, and the ferromagnetism weakens. Moreover, the decrease in the saturation magnetization for films deposited in N2 atmosphere is more apparent than that deposited in O2 atmosphere. We think the reason is that in our Fe-doped In2O3 films the ferromagnetism is mainly mediated by the oxygen vacancies, and as an acceptor defect, N ions can decrease the concentration of the oxygen vacancies to a greater extent than the O ions.

Achieving room temperature DNA amplification by dialling in destabilization

2015 ◽  
Vol 51 (44) ◽  
pp. 9101-9104 ◽  
Author(s):  
B. Safeenaz Alladin-Mustan ◽  
Catherine J. Mitran ◽  
Julianne M. Gibbs-Davis
Keyword(s):  
Nucleic Acid ◽  
Room Temperature ◽  
Point Of Care ◽  
Dna Amplification ◽  
Heating Element ◽  
Nucleic Acid Sequences

The ability to amplify nucleic acid sequences at room temperature without the need for any heating element has been achieved, which has promise in bio-diagnostics employed at the point of care.

scholarly journals Pre-harvest application of salicylic acid influence physicochemical and quality characteristics of ‘Chimarrita’ peaches during cold storage

2019 ◽  
pp. 46
Author(s):  
Jakellinye Miranda ◽  
Suélen Braga de Andrade, Andressa Vighi Schiavon ◽  
Pedro Luis Panisson Kaltbach Lemos ◽  
Cláudia Simone Madruga Lima ◽  
Marcelo Barbosa Malgarim
Keyword(s):  
Salicylic Acid ◽  
Shelf Life ◽  
Cold Storage ◽  
Room Temperature ◽  
Soluble Solids ◽  
Acid Solutions ◽  
Post Harvest ◽  
Hue Angle ◽  
Cold Chamber

Peach is a climacteric highly-perishable fruit whose post-harvest preservation relies largely on cold storage. The combination of the last with other technologies allows to extend the shelf life of this product. One alternative is the utilization of salicylic acid, a natural compound involved in many physiological phenomena such as resistance against diseases and ripening. Considering these facts, the objective of the present work was to evaluate the effect of pre-harvest application of salicylic acid solutions on the quality of ‘Chimarrita’ peaches during post-harvest cold storage. The experiment was conducted at the Federal University of Pelotas/RS, in the campus of Capão do Leão/RS - Brazil. The application of salicylic acid solutions was performed by direct pulverization on the fruits, 30 days prior to harvest. The concentrations were: 0,0 (control); 1,0; 1,5; and 2,0 mM. After harvest, the fruits were stored in a cold chamber at 1,0 ± 0,5°C and 85-90% RH, for 30 days. The analyses were performed at the following cold storage periods (plus 2 days at room temperature of 20°C to all treatments, in order to simulate commercialization conditions): 10 (+2) days; 20 (+2) days; e 30 (+2) days. The variables evaluated were: mass loss (%); flesh firmness (N); DA index; color (L, a*, b* and hue angle); wooliness incidence (%); rot incidence (%); total soluble solids (°Brix); pH; titrable acidity (% of organic acids); and ratio. The salicylic acid doses and/or the cold storage periods had significant effects on all the evaluated parameters. For most of the parameters analyzed, the intermediate dosis of 1mM (and also 1,5mM) of salicilic acid showed the most promising results. Therefore, the application of salicylic acid solutions 30 days prior to harvest is a technique which can be combined to cold storage in order to shift the quality and the shelf-life of ‘Chimarrita’ peaches.

Deposition of Thin Films of Silicon Carbide on Fused Quartz and on Sapphire by Laser Ablation of Ceramic Silicon Carbide Targets

1992 ◽  
Vol 285 ◽  
Author(s):  
L. Rimai ◽  
R. Ager ◽  
J. Hangas ◽  
E. M. Loaothetis ◽  
Nayef Abu-ageel ◽  
...  
Keyword(s):  
Thin Films ◽  
Silicon Carbide ◽  
Room Temperature ◽  
Optical Band Gap ◽  
Energy Gap ◽  
Fused Silica ◽  
High Resistivity ◽  
Fused Quartz ◽  
Amorphous Sic ◽  
Very High

ABSTRACTAblation of ceramic silicon carbide with 351 nm excimer radiation was used to depositSIC films on fused silica and on sapphire. For deposition temperatures above 850° C, diffraction shows the films to be crystalline with the [111] axis preferentially oriented normally to the film. Optical spectra show an indirect energy gap at 2.2 eV, near that for the cubic polytype, although the 200 diffractions are absent. Room temperature resistivities range between .02 to .1 Ωcm. Deposition below 600° C yields amorphous SiC with no diffraction bands, low and variable optical band gap and very high resistivity.

Impact of Cationic Molecular Length of Ionic Liquid Electrolytes on Cell Performances of 18650 Supercapacitors

2021 ◽  
Author(s):  
Phatsawit Wuamprakhon ◽  
Ruttiyakorn Donthongkwa ◽  
Kanit Hantanasirisakul ◽  
Vinich Promarak ◽  
Jumras Limtrakul ◽  
...  
Keyword(s):  
Ionic Liquid ◽  
Ionic Liquids ◽  
Porous Carbon ◽  
Room Temperature ◽  
Series Resistance ◽  
Room Temperature Ionic Liquids ◽  
Specific Cell ◽  
Equivalent Series Resistance ◽  
Molecular Length ◽  
Cell Capacitance

The specific cell capacitance, equivalent series resistance (ESR) and equivalent distributed resistance (EDR) of porous carbon-based supercapacitors linearly depend on the cation molecular length (1 dimension) of room-temperature ionic liquids.

PITTING MECHANISM OF MILD STEEL IN MARGINALLY SOUR ENVIRONMENTS: PIT PROPAGATION BASED ON ACIDIFICATION BY CATALYTIC OXIDATION OF DISSOLVED HYDROGEN SULFIDE

CORROSION ◽  
10.5006/3858 ◽  
2021 ◽  
Author(s):  
Wei Zhang ◽  
Bruce Brown ◽  
David Young ◽  
Stephen Smith ◽  
Sytze Huizinga ◽  
...  
Keyword(s):  
Hydrogen Sulfide ◽  
Mild Steel ◽  
Experimental Measurement ◽  
Thermodynamic Calculation ◽  
Room Temperature ◽  
Steel Surface ◽  
Saturation Degree ◽  
Transitional Metal ◽  
Dissolved Hydrogen ◽  
Dissolved O2

The present work studies pit propagation in marginally sour environments and proposes a credible mechanism. Both thermodynamic calculation and experimental measurement confirmed that H2S can be oxidized by traces of dissolved O2 into SO42- and H+ in the aqueous solutions near room temperature with the transitional metal ions serving as a catalyst. This acidification phenomenon would be more effective near the steel surface, especially inside a pit, where Fe2+ ions are most abundant. Therefore, the saturation degree of mackinawite would be lower inside the pit, which would prohibit the pitting from annihilation.

scholarly journals Calculated Terahertz Spectra of Glycine Oligopeptide Solutions Confined in Carbon Nanotubes

Polymers ◽  
2019 ◽  
Vol 11 (2) ◽  
pp. 385 ◽  
Author(s):  
Dongxiong Ling ◽  
Mingkun Zhang ◽  
Jianxun Song ◽  
Dongshan Wei
Keyword(s):  
Carbon Nanotubes ◽  
Signal To Noise Ratio ◽  
Thz Spectroscopy ◽  
Water Molecules ◽  
Relaxation Dynamics ◽  
Confinement Effects ◽  
Nanofluidic Channels ◽  
Detection Of Biomolecules ◽  
Thz Absorption ◽  
Dynamics Simulations

To reduce the intense terahertz (THz) wave absorption of water and increase the signal-to-noise ratio, the THz spectroscopy detection of biomolecules usually operates using the nanofluidic channel technologies in practice. The effects of confinement due to the existence of nanofluidic channels on the conformation and dynamics of biomolecules are well known. However, studies of confinement effects on the THz spectra of biomolecules are still not clear. In this work, extensive all-atom molecular dynamics simulations are performed to investigate the THz spectra of the glycine oligopeptide solutions in free and confined environments. THz spectra of the oligopeptide solutions confined in carbon nanotubes (CNTs) with different radii are calculated and compared. Results indicate that with the increase of the degree of confinement (the reverse of the radius of CNT), the THz absorption coefficient decreases monotonically. By analyzing the diffusion coefficient and dielectric relaxation dynamics, the hydrogen bond life, and the vibration density of the state of the water molecules in free solution and in CNTs, we conclude that the confinement effects on the THz spectra of biomolecule solutions are mainly to slow down the dynamics of water molecules and hence to reduce the THz absorption of the whole solution in confined environments.

Infrared Study of Acetic Acid Solutions in CCl4

1995 ◽  
Vol 60 (7) ◽  
pp. 1094-1100 ◽  
Author(s):  
Ivona Malijevská ◽  
Martin Polášek
Keyword(s):  
Acetic Acid ◽  
Regression Analysis ◽  
Carbon Tetrachloride ◽  
Room Temperature ◽  
Equilibrium Constants ◽  
Acid Solutions ◽  
Standard State ◽  
Infrared Study ◽  
Mean Values ◽  
Linear Dimer

Spectra of acetic acid solutions in carbon tetrachloride were taken at room temperature over the concentration range 0.025-0.00125 mol dm-3. Solutions of acetic acid were modelled as an ideal mixture of monomers, and cyclic and linear dimers. Regression analysis effected separation of the experimental envelope into its component bands. Band shapes were approximated by a Lorenzian function with the resolved band peak frequencies 1 712 cm-1 for the cyclic dimer, 1 724 cm-1 for the linear dimer and 1 765 cm-1 for the acetic acid monomer. Mean values of equilibrium constants for the standard state of unit concentration are 2 700 for the cyclic and 393 for the linear dimer, respectively.

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