scholarly journals Safety of Concentrated Bioshell Calcium Oxide Water Application for Surface and Skin Disinfections against Pathogenic Microbes

Molecules ◽  
2020 ◽  
Vol 25 (19) ◽  
pp. 4502
Author(s):  
Masayuki Ishihara ◽  
Yuuki Hata ◽  
Sumiyo Hiruma ◽  
Tomohiro Takayama ◽  
Shingo Nakamura ◽  
...  
Keyword(s):  
Calcium Oxide ◽  
Ambient Air ◽  
Powder Coating ◽  
Water Application ◽  
X Ray ◽  
Living Body ◽  
Wood Piece ◽  
High Alkalinity ◽  
Pathogenic Microbes ◽  
Microscopy Images

Immediately post-production, commercially available bioshell calcium oxide (BiSCaO) water is colorless, transparent, and strongly alkaline (pH 12.8), and is known to possess deodorizing properties and broad microbicidal activity. However, BiSCaO Water may represent a serious safety risk to the living body, given the strong alkalinity. This study aimed to investigate the safety of BiSCaO Water for use as an antiseptic/disinfectant despite concerns regarding its high alkalinity. The change over time in pH of BiSCaO Water was measured during air contact (stirring BiSCaO Water in ambient air). When sprayed on metal, plastic, wood piece, paper, and skin surfaces, the pH of BiSCaO Water decreased rapidly, providing a white powder coating upon drying. Scanning electron microscopy images, energy dispersive X-ray elemental mapping, and X-ray diffractograms showed that the dried powder residues of BiSCaO Water were composed primarily of calcium carbonate. These results suggested that BiSCaO Water is a potent reagent that may overcome the obstacles of being strongly alkaline, making this material appropriate for use in disinfection against pathogenic microbes.

scholarly journals Characterization of calcium oxide in root perforation sealer materials

2012 ◽  
Vol 23 (5) ◽  
pp. 539-546 ◽  
Author(s):  
Carlos Estrela ◽  
Manoel Damião Sousa-Neto ◽  
Orlando Aguirre Guedes ◽  
Ana Helena Gonçalves Alencar ◽  
Marco Antonio Hungaro Duarte ◽  
...  
Keyword(s):  
Calcium Oxide ◽  
Mineral Trioxide Aggregate ◽  
Chemical Compounds ◽  
Internal Diameter ◽  
X Ray ◽  
Final Sample ◽  
Materials Used ◽  
Main Components ◽  
White Mineral

Root perforation represents an undesirable complication that may lead to an unfavorable prognosis. The aims of this study were to characterize and to compare the presence of calcium oxide (CaO) on the chemical composition of materials used for root perforation therapy: gray and white mineral trioxide aggregate (MTA) and Portland cement (PC), gray MTA+5%CaO and gray MTA+10%CaO. The last two materials were analyzed to evaluate the increase of CaO in the final sample. CaO alone was used as a standard. Eighteen polyethylene tubes with an internal diameter of 3 mm and 3 mm in length were prepared, filled and then transferred to a chamber with 95% relative humidity and a temperature of 37ºC. The chemical compounds (particularly CaO) and the main components were analyzed by energy-dispersive X-ray microanalysis (EDX). EDX revealed the following concentrations of CaO: gray MTA: 59.28%, white MTA: 63.09%; PC: 72.51%; gray MTA+5%CaO: 63.48% and gray MTA+10%CaO: 67.55%. The tested materials presented different concentrations of CaO. Even with an increase of 5 and 10% CaO in gray MTA, the CaO levels found in the MTA samples were lower than those found in PC.

scholarly journals Green Synthesis of Feather-Shaped MoS2/CdS Photocatalyst for Effective Hydrogen Production

2013 ◽  
Vol 2013 ◽  
pp. 1-5 ◽  
Author(s):  
Yang Liu ◽  
Hongtao Yu ◽  
Xie Quan ◽  
Shuo Chen
Keyword(s):  
Electron Microscopy ◽  
Hydrogen Production ◽  
Photoelectron Spectroscopy ◽  
Diffuse Reflectance ◽  
Sulfur Source ◽  
X Ray ◽  
Transmission Electron ◽  
Microscopy Images ◽  
Effective Hydrogen ◽  
Better Than

MoS2/CdS photocatalyst was fabricated by a hydrothermal method for H2production under visible light. This method used low toxic thiourea as a sulfur source and was carried out at 200°C. Thus, it was better than the traditional methods, which are based on an annealing process at relatively high temperature (above 400°C) using toxic H2S as reducing agent. Scanning electron microscopy and transmission electron microscopy images showed that the morphologies of MoS2/CdS samples were feather shaped and MoS2layer was on the surface of CdS. The X-ray photoelectron spectroscopy testified that the sample was composed of stoichiometric MoS2and CdS. The UV-vis diffuse reflectance spectra displayed that the loading of MoS2can enhance the optical absorption of MoS2/CdS. The photocatalytic activity of MoS2/CdS was evaluated by producing hydrogen. The hydrogen production rate on MoS2/CdS reached 192 μmol·h−1. This performance was stable during three repeated photocatalytic processes.

scholarly journals Controlling water evaporation through self-assembly

2016 ◽  
Vol 113 (37) ◽  
pp. 10275-10280 ◽  
Author(s):  
Kevin Roger ◽  
Marianne Liebi ◽  
Jimmy Heimdal ◽  
Quoc Dat Pham ◽  
Emma Sparr
Keyword(s):  
Self Assembly ◽  
Feedback Loop ◽  
Ambient Air ◽  
Underlying Mechanism ◽  
Water Evaporation ◽  
Air Humidity ◽  
X Ray ◽  
X Ray Scattering ◽  
Composition And Structure ◽  
Living Organisms

Water evaporation concerns all land-living organisms, as ambient air is dryer than their corresponding equilibrium humidity. Contrarily to plants, mammals are covered with a skin that not only hinders evaporation but also maintains its rate at a nearly constant value, independently of air humidity. Here, we show that simple amphiphiles/water systems reproduce this behavior, which suggests a common underlying mechanism originating from responding self-assembly structures. The composition and structure gradients arising from the evaporation process were characterized using optical microscopy, infrared microscopy, and small-angle X-ray scattering. We observed a thin and dry outer phase that responds to changes in air humidity by increasing its thickness as the air becomes dryer, which decreases its permeability to water, thus counterbalancing the increase in the evaporation driving force. This thin and dry outer phase therefore shields the systems from humidity variations. Such a feedback loop achieves a homeostatic regulation of water evaporation.

Characterizing the Thermomechanical Degradation of a Filled Elastomer by Morphology and X Ray Photoelectron Spectroscopy

2001 ◽  
Vol 702 ◽  
Author(s):  
Giovanni F Crosta ◽  
Art J Nelson ◽  
Marina C Camatini
Keyword(s):  
Photoelectron Spectroscopy ◽  
Intrinsic Property ◽  
Binding Energies ◽  
Structural Domain ◽  
X Ray ◽  
Vulcanized Rubber ◽  
A Value ◽  
Debris Particles ◽  
Morphological Descriptor ◽  
Microscopy Images

ABSTRACTThree types of debris particles, denoted by L2, H2 and K3 respectively, originated from the abrasion of silica-filled, vulcanized rubber under different test conditions (severity) were analyzed and compared. The structural fractal dimension, DFS, of the particle perimeter was chosen as a morphological descriptor (but not necessarily as an intrinsic property of the fractured material !). Said dimension was estimated by processing light microscopy images. A value of the morphological threshold, TST, which separates the textural from the structural domain in the RICHARDSON plot was determined in order to maximize discrimination between the three particle types and rank them by increasing values of DFS. Particles from the highest severity test (K3) exhibited the highest value of DFS. X ray photoelectron spectroscopy (XPS) provided elemental composition, core level binding energies and the speciation of C, N, O, Si and S. As a result, L2 debris was found to originate from two processes: fracture of rubber and segregation of extender oil. Evidence has come both from morphology and XPS. Particles of H2 and K3 were ascribed to fracture alone. Comparison between K3 and the reference material, rasped rubber (RAS), shows the following: a) increase of the [S]/[C] surface atomic concentration ratio from RAS to K3; b) existence of multiple bonding states of S in K3 with energy peaking at 162.9 ± 0.3 eV ([-S-S-]n); c) weak contribution of R-S-O-R oxidized S species in K3 at 165 eV, not seen in RAS; d) no evidence of either SO3 or SO4 groups in any material. Although preliminary, these results prove the ability of morphological analysis and XPS to characterize the surface properties of debris particles non destructively.

Facile Refluxing Synthesis of Hydroxyapatite Nanoparticles

2015 ◽  
Vol 68 (8) ◽  
pp. 1293 ◽  
Author(s):  
Pakvipar Chaopanich ◽  
Punnama Siriphannon
Keyword(s):  
Crystallite Size ◽  
Reaction Times ◽  
Single Step ◽  
Hydroxyapatite Nanoparticles ◽  
X Ray Diffraction ◽  
X Ray ◽  
Transmission Electron ◽  
Aqueous Mixture ◽  
Diffraction Patterns ◽  
Microscopy Images

Hydroxyapatite (HAp) nanoparticles were successfully synthesized from an aqueous mixture of Ca(NO3)2·4H2O and (NH4)2HPO4 by a facile single-step refluxing method using polystyrene sulfonate (PSS) as a template. The effects of reaction times, pH, and PSS concentration on the HAp formation were investigated. It was found that the crystalline HAp was obtained under all conditions after refluxing the precursors for 3 and 6 h. The longer refluxing time, the greater the crystallinity and the larger the crystallite size of the HAp nanoparticles. The HAp with poor crystallinity was obtained at pH 8.5; however, the well-crystallized HAp was obtained when reaction pH was increased to 9.5 and 10.5. In addition, the X-ray diffraction patterns revealed that the presence of PSS template caused the reduction of HAp crystallite size along the (002) plane from 52.6 nm of non-template HAp to 43.4 nm and 41.4 nm of HAp with 0.05 and 0.2 wt-% PSS template, respectively. Transmission electron microscopy images of the synthesized HAp revealed the rod-shaped crystals of all samples. The synthesized HAp nanoparticles were modified by l-aspartic acid (Asp) and l-arginine (Arg), having negative and positive charges, respectively. It was found that the zeta potential of HAp was significantly changed from +5.46 to –24.70 mV after modification with Asp, whereas it was +4.72 mV in the Arg-modified HAp. These results suggested that the negatively charged amino acid was preferentially adsorbed onto the synthesized HAp surface.

scholarly journals Peran Kontaminasi Kerak pada Diferensiasi Magma Pembentuk Batuan Vulkanik Sungai Ampalas, Mamuju, Sulawesi Barat

EKSPLORIUM ◽  
2020 ◽  
Vol 41 (2) ◽  
pp. 73
Author(s):  
Windi Anarta Draniswari ◽  
Sekar Indah Tri Kusuma ◽  
Tyto Baskara Adimedha ◽  
I Gde Sukadana
Keyword(s):  
Magma Mixing ◽  
Volcanic Rocks ◽  
Geochemical Characteristics ◽  
X Ray ◽  
Radioactive Mineral ◽  
Alkaline Feldspar ◽  
High Alkalinity ◽  
Preliminary Study ◽  
Xrf Analyses

ABSTRAK Anomali radiometri telah ditemukan di area Sungai Amplas pada bongkah batuan vulkanik. Nilai yang terukur dari spektrometer gama adalah 787 ppm eU dan 223 ppm eTh. Penemuan ini menarik untuk pengembangan eksplorasi. Studi lebih lanjut diperlukan untuk mengetahui karekteristik batuan pembawa mineral radioaktif dari sampel in-situ. Penelitian ini bertujuan untuk mengetahui karakteristik petrologi dan geokimia batuan vulkanik Ampalas sebagai studi awal untuk mengetahui proses akumulasi mineral radioaktif pada batuan vulkanik Ampalas. Metodologi yang digunakan meliputi pengamatan lapangan, pengambilan sampel batuan, analisis petrografi dan X-Ray Fluorescence (XRF). Batuan vulkanik ampalas tersusun atas ponolit, foidit, dan foid-syenit. Tekstur batuannya terdiri dari porfiritik, aliran, rim piroksen, zoning, pseudo-leusit, korosi, inklusi mafik, dan sieve. Karakteristik geokimia menunjukkan alkalinitas tinggi dan indikasi pengayaan mineral radioaktif yang tersebar dalam batuan. Proses magmatis yang berperan dalam pembentukan batuan vulkanik adalah fraksionasi kristal (fraksionasi leusit dan alkali felspar), asimilasi kerak kontinen, dan pencampuran magma. Interaksi antara magma dan kerak menyebabkan diferensiasi magma berkelanjutan yang menghasilkan akumulasi uranium dan torium lebih tinggi.ABSTRACT Anomalous radiometry has been found in Ampalas River Area on volcanic rock boulder. The values measured from gamma spectrometer are 787 ppm eU and 223 ppm eTh. This discovery is promising for exploration development. Further study need to figure the radioactive mineral bearing rock characteristic from in-situ samples. The research aim is to determine the petrology and geochemical characteristics of Ampalas volcanic rocks as preliminary study to find radioactive mineral accumulation process of Ampalas volcanic rocks. The methodologies are field observation, rock sampling, petrography, and X-Ray fluorescence (XRF) analyses. The Ampalas volcanic rocks consist of phonolite, phoidite, and phoid syenite. Their textures are porphyritic, flow, pyroxene rim, zoning, pseudo-leucite, corrosion, mafic inclusions, and sieve. The geochemical characteristics show high alkalinity and radioactive mineral enrichment disseminating on rock. The magmatic processes which play a significant role in radioactive mineral-bearing rocks formation are crystal fractionations (leucite and alkaline feldspar fractionations), continental crust assimilation, and magma mixing. Long interaction between magma and crust creates advanced magma differentiation causing higher uranium and thorium accumulation.  

scholarly journals Nuclear incorporation of iron during the eukaryotic cell cycle

2016 ◽  
Vol 23 (6) ◽  
pp. 1490-1497 ◽  
Author(s):  
Ian Robinson ◽  
Yang Yang ◽  
Fucai Zhang ◽  
Christophe Lynch ◽  
Mohammed Yusuf ◽  
...  
Keyword(s):  
Cell Cycle ◽  
Fluorescence Microscopy ◽  
Phase Contrast ◽  
Eukaryotic Cell ◽  
Inhomogeneous Distribution ◽  
Cell Nuclei ◽  
X Ray ◽  
Microscopy Images ◽  
Different Levels

Scanning X-ray fluorescence microscopy has been used to probe the distribution of S, P and Fe within cell nuclei. Nuclei, which may have originated at different phases of the cell cycle, are found to show very different levels of Fe present with a strongly inhomogeneous distribution. P and S signals, presumably from DNA and associated nucleosomes, are high and relatively uniform across all the nuclei; these agree with X-ray phase contrast projection microscopy images of the same samples. Possible reasons for the Fe incorporation are discussed.

scholarly journals Evaluation of Shell-Derived Calcium Oxide Catalysts for the Production of Biodiesel Esters from Cooking Oils

2021 ◽  
pp. 20-27
Author(s):  
Ngee Sing Chong ◽  
Francis Uchenna Okejiri ◽  
Saidi Abdulramoni ◽  
Shruthi Perna ◽  
Beng Guat Ooi
Keyword(s):  
Calcium Oxide ◽  
Waste Cooking Oil ◽  
Biodiesel Production ◽  
Molar Ratio ◽  
X Ray ◽  
Cooking Oil ◽  
Biodiesel Synthesis ◽  
Cooking Oils ◽  
The Cost ◽  
Percentage Conversion

Due to the high cost of feedstock and catalyst in biodiesel production, the viability of the biodiesel industry has been dependent on government subsidies or tax incentives. In order to reduce the cost of production, food wastes including eggshells and oyster shells have been used to prepare calcium oxide (CaO) catalysts for the transesterification reaction of biodiesel synthesis. The shells were calcined at 1000 °C for 4 hours to obtain CaO powders which were investigated as catalysts for the transesterification of waste cooking oil. The catalysts were characterized by Fourier Transform infrared (FTIR) spectroscopy, thermogravimetric analysis (TGA), X-ray powder diffraction (XRD), and X-ray fluorescence (XRF) spectroscopy. Reaction parameters such as methanol-to-oil molar ratio, CaO catalyst concentration, and reaction time were evaluated and optimized for the percentage conversion of cooking oil to biodiesel esters. The oyster-based CaO showed better catalytic activity when compared to the eggshell-based CaO under the same set of reaction conditions.

Thermally Induced Superlow Friction of DLC Films in Ambient Air

2018 ◽  
Vol 37 (8) ◽  
pp. 725-731 ◽  
Author(s):  
Qunfeng Zeng
Keyword(s):  
Photoelectron Spectroscopy ◽  
Ambient Air ◽  
Friction Model ◽  
Repulsive Force ◽  
Hydroxyl Group ◽  
Thermally Induced ◽  
X Ray ◽  
Thermally Activated ◽  
Charged Interface ◽  
Positively Charged

AbstractThermally induced superlow friction (0.008) of diamond-like carbon (DLC) films was achieved in ambient air in the present work. Raman and XPS (X-ray Photoelectron Spectroscopy) measurements and analyses show that superlow friction of the annealed DLC films is involved in the transformation of sp3 to sp2 hybridized carbon during annealing and the tribochemical reactions during sliding. The thermally activated graphitization and oxidation of the annealed DLC films in ambient air is beneficial to form the positively charged interface and achieve the stable superlow friction. A friction model was developed and applied to explain superlow friction, which is attributed to Van de Waals force between graphite layers and the repulsive force between hydroxyl group of graphite oxide and hydrogen terminated DLC films surface.

Resolution and Feature Size Assessment in Soft X-Ray Microscopy Images

2009 ◽  
pp. 483-488
Author(s):  
M. C. Marconi ◽  
P. W. Wachulak ◽  
C. Brewer ◽  
F. Brizuela ◽  
R. Bartels ◽  
...  
Keyword(s):  
Feature Size ◽  
X Ray ◽  
Microscopy Images
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