scholarly journals Graphene-Based Raman Spectroscopy for pH Sensing of X-rays Exposed and Unexposed Culture Media and Cells

Sensors ◽  
2018 ◽  
Vol 18 (7) ◽  
pp. 2242 ◽  
Author(s):  
Carlo Camerlingo ◽  
Alessandro Verde ◽  
Lorenzo Manti ◽  
Roberta Meschini ◽  
Ines Delfino ◽  
...  
Keyword(s):  
Raman Spectroscopy ◽  
Ph Value ◽  
Culture Media ◽  
Biological Fluids ◽  
X Rays ◽  
Ph Sensing ◽  
X Ray ◽  
Graphene Layers ◽  
Ph Values ◽  
Metabolic Activities

Graphene provides a unique way of sensing the local pH level of substances on the micrometric scale, with important implications for the monitoring of cellular metabolic activities where proton excretion could occur. Accordingly, an innovative biosensing approach for the quantification of the pH value of biological fluids, to be used also with small amounts of fluids, was realized and tested. It is based on the use of micro-Raman spectroscopy to detect the modifications of the graphene doping level induced by the contact of the graphene with the selected fluids. The approach was preliminarily tested on aqueous solutions of known pH values. It was then used to quantify the pH values of cell culture media directly exposed to different doses of X-ray radiation and to media exposed to X-ray-irradiated cells. The Raman response of cells placed on graphene layers was also examined.

Study on Influence of Silicate Morphology Based on pH Value

2012 ◽  
Vol 454 ◽  
pp. 324-328
Author(s):  
Yan He ◽  
Ya Jing Liu ◽  
Yong Lin Cao ◽  
Li Xia Zhou
Keyword(s):  
Silicic Acid ◽  
Ph Value ◽  
Colorimetric Method ◽  
Absorption Spectrometry ◽  
Degree Of Polymerization ◽  
Raw Material ◽  
X Ray Diffraction ◽  
X Ray ◽  
Ph Values ◽  
The Stability

Infra-red absorption spectrometry, X-ray diffraction observations and characterization tests based on silicon molybdenum colorimetric method were used to investigate the optimal pH value controlling the stability of the silicic acid form. The experiment process was done by using sodium silicate as raw material. The results showed that the solution of silicate influenced the polymerization. The active silicic acid solution with a certain degree of polymerization was obtained by controlling the pH values.

scholarly journals The Influence of pH Values on the Crystallite Size of ZnO by Solvothermal Synthesis

2017 ◽  
Vol 2 (2) ◽  
pp. 118 ◽  
Author(s):  
Ahmadi Jaya Permana ◽  
Dian Wulandari ◽  
Hartati Hartati ◽  
Harsasi Setyawati ◽  
Mochammad Zakki Fahmi
Keyword(s):  
Heat Treatment ◽  
Zinc Oxide ◽  
Crystallite Size ◽  
Solvothermal Synthesis ◽  
Solvothermal Method ◽  
Ph Value ◽  
Semiconductor Material ◽  
X Ray ◽  
Ph Values ◽  
Influence Of Ph

 Zinc oxide (ZnO) is a semiconductor material that widely used in various applications due to its unique properties. Synthesis of ZnO by solvothermal method has been conducted with controlled pH values. The variations of pH value were 10, 11 and 12 by adjusting NaOH content. Crystall structure of the synthesis products after heat treatment at 110oC and 600oC has characterised by X-ray Diffratometer (XRD). Crystallite size of ZnO was measured by Scherrer equation. Crystall phase of ZnO has been observed on all pH value variations at 110 oC with 22,98-37,06 nm of crystallite size, whereas ZnO has been observed on all pH value variations at 600 oC with 41,39-71,77 nm of crystallite size.Keywords: ZnO, pH values, crystallite size, solvothermal

Influence of pH on the Morphology and Luminescence Properties of Europium-Doped Hydroxyapatite Nanoparticles

2011 ◽  
Vol 391-392 ◽  
pp. 1132-1137
Author(s):  
Su Ping Huang ◽  
Jun Zhu ◽  
Ke Chao Zhou
Keyword(s):  
Photoelectron Spectroscopy ◽  
Inductively Coupled Plasma ◽  
Doping Concentration ◽  
Ph Value ◽  
Luminescence Properties ◽  
X Ray Diffraction ◽  
X Ray ◽  
Inductively Coupled ◽  
Ph Values ◽  
Influence Of Ph

Luminescence behaviors and morphology of Eu3+doped hydroxyapatite synthesized under different pH values were well investigated by X-ray diffraction (XRD), scanning electronic microscopy (SEM), X-ray photoelectron spectroscopy (XPS), Inductively Coupled Plasma (ICP) (ICP–PLASMA 1000), and photoluminescence (PL) spectroscopy. Results revealed that With pH values increased from 6.5 to 10.0, the morphology of nano-Eu:HA particles changes from rod particles to equiaxed particles. The actual doping concentration and aspect ratio of Eu3+-doped HA decreased with the increasing of pH value. At the same time, the fluorescence intensity also tends to weakly lower with the increasing of pH value, which indicated that the luminescence properties mainly depended on the actual Eu3+doping concentration, the influences of morphology on the luminescence properties were slight.

Preparation and Fluorescence Properties of GdF3:Eu3+, NaGdF4:Eu3+ Materials

2013 ◽  
Vol 661 ◽  
pp. 74-78
Author(s):  
Li Li Wang ◽  
Lian Li Liu ◽  
Qian Xu ◽  
Tong Sun ◽  
Wan Na Gu
Keyword(s):  
Aqueous Solution ◽  
Phase Composition ◽  
Polyethylene Glycol ◽  
Ph Value ◽  
Hexagonal Phase ◽  
Raw Material ◽  
Fluorescence Properties ◽  
X Ray ◽  
Ph Values ◽  
Molecular Fluorescence

The GdF3:Eu3+and NaGdF4:Eu3+powders were synthesized by hydrothermal method as raw material of Gd2O3, Eu2O3, NaF, NH4HF2, EDTA and polyethylene glycol. The powders were characterized by means of X-ray powder diffraction, SEM microscopy and Molecular fluorescence photometer. It was discussed that the pH value of aqueous solution had affection on the phase composition of synthesized powders. The complex fluorides GdF3and NaGdF4were synthesized in aqueous solution at the pH values between 3 and 6. The synthesized powders were single hexagonal phase of NaGdF4 crystal at pH=8. It was also found that different fluorescence properties were exhibited by Eu3+doping powders synthesized at different pH values of aqueous solution. The synthesized powders of GdF3and NaGdF4were excellent fluorescence materials.

Effects of pH Values on the Structure, Composition and Luminescence of CaWO4:Tb3+ Thin Films

2012 ◽  
Vol 531-532 ◽  
pp. 204-207
Author(s):  
Lian Ping Chen ◽  
Yuan Hong Gao
Keyword(s):  
Thin Films ◽  
Ph Value ◽  
Electrochemical Techniques ◽  
Luminescent Properties ◽  
X Ray Diffraction ◽  
Step Method ◽  
X Ray ◽  
Ph Values ◽  
Effects Of Ph ◽  
Rare Earth Doped

It is hardly possible to obtain rare earth doped CaWO4thin films directly through electrochemical techniques. A two-step method has been proposed to synthesize Tb3+-doped CaWO4thin films. X-ray diffraction, energy dispersive X-ray analysis, spectrophotometer were used to characterize their phase, composition and luminescent properties. Results reveal that Tb3+-doped CaWO4films have a tetragonal phase. The ratio of n(Tb)/[n(Ca)+n(Tb)+n(Na)] decreases with the increase of pH value of TbCl3solutions. When the pH value (adjusted by NaOH) is higher than 5, Na element has been detected in CaWO4:Tb3+thin films. Based on the analysis on the composition and luminescence, it can be concluded that the pH value of TbCl3solutions must be no higher than 9.1, otherwise, no Tb3+-doped CaWO4thin films can be obtained. Under the excitation of 237 nm, sharp emission peaks at 543 and 489 nm have been observed for Tb3+-doped CaWO4:Tb3+thin films.

scholarly journals Hard X-rays in–soft X-rays out: An operando piggyback view deep into a charging lithium ion battery with X-ray Raman spectroscopy

2015 ◽  
Vol 200 ◽  
pp. 257-263 ◽  
Author(s):  
Artur Braun ◽  
Dennis Nordlund ◽  
Seung-Wan Song ◽  
Tzu-Wen Huang ◽  
Dimosthenis Sokaras ◽  
...  
Keyword(s):  
Raman Spectroscopy ◽  
Lithium Ion Battery ◽  
Lithium Ion ◽  
X Rays ◽  
X Ray

Hydration Phenomena in a Concentrated Aqueous Solution of Ce(NO3)3. X-ray Diffraction and Raman Spectroscopy

1983 ◽  
Vol 38 (5) ◽  
pp. 533-539 ◽  
Author(s):  
R. Caminiti ◽  
P. Cucca ◽  
A. D′Andrea
Keyword(s):  
Experimental Data ◽  
Aqueous Solution ◽  
Raman Spectroscopy ◽  
Correlation Function ◽  
Hydration Shell ◽  
X Rays ◽  
X Ray Diffraction ◽  
X Ray ◽  
Experimental Correlation ◽  
Good Agreement

The scattering of X-rays from a concentrated Ce(NO3)3 aqueous solution has been measured and analyzed. The experimental correlation function appears to be mainly characterized by the hydration of the cation: peaks at about 2.55 and 4.65 Å. Good agreement with experimental data is achieved through a model in which the Ce(III) ions have a first and a second hydration shell and also the nitrate group is considered hydrated. Complex formation between cation and anion is confirmed by using Raman spectroscopy.

Study on Stability of AgI/TiO2 Visible Light Photocatalysts in Solutions of Various pH Values

2011 ◽  
Vol 399-401 ◽  
pp. 1272-1275
Author(s):  
Lu Feng ◽  
Ke Feng He ◽  
Wan Ping Chen
Keyword(s):  
Visible Light ◽  
Absorption Edge ◽  
Ph Value ◽  
Alkaline Treatment ◽  
Alkaline Solutions ◽  
X Ray Diffraction ◽  
X Ray ◽  
Acidic Solutions ◽  
Ph Values ◽  
Vis Spectroscopy

Nanostructured AgI/TiO2 photocatalysts exhibit highly efficient visible light photocatalytic activity. Though there have been extensive investigations on AgI/TiO2 photocatalysts, study on their stablity is still very limited. So in this paper, such a study is designed and conducted. AgI/TiO2 nanostructured photocatalysts were prepared and separately immersed in HCl solutions, DI water and NaOH solutions with pH value of 0, 4, 7, 10 and 14, respectively. X-ray diffraction and diffusive reflectance UV-vis spectroscopy analyses reveal that the immersion in acidic solutions led to the formation of AgCl and a blue shifting to 450nm for the absorption edge of AgI/TiO2, while the alkaline treatment had no significant effect on the composite structure of AgI/TiO2 or on the UV-vis absorption edge. Photocatalytic tests show that immersion in acidic solutions had more significant influence on AgI/TiO2 photocatalytic degradation of methyl orange (MO). At pH = 4, photocatalytic efficiency was dropped nearly 30%. At pH = 10, no significant change was observed. AgI/TiO2 nanostructured photocatalysts have thus been found to display a higher stability in alkaline solutions than in acidic solutions.

EFFECT OF pH ON ZnS NANOCRYSTALLINE THIN FILM EMBEDDED IN A POLYVINYL ALCOHOL MATRIX

2010 ◽  
Vol 24 (29) ◽  
pp. 5663-5673 ◽  
Author(s):  
J. P. BORAH ◽  
J. BARMAN ◽  
K. C. SARMA
Keyword(s):  
Electron Microscopy ◽  
Polyvinyl Alcohol ◽  
Ph Value ◽  
X Ray Diffraction ◽  
X Ray ◽  
Ph Values ◽  
Nanocrystalline Thin Film ◽  
Transmission Electron ◽  
Uv Visible ◽  
Compositional Characterization

Polyvinyl alcohol (PVA) has been used as a matrix to synthesize ZnS / PVA nanocomposite film on glass substrate by chemical method. Transmission electron microscopy (TEM), X-ray diffraction (XRD), Scanning electron microscopy (SEM) has been used for structural, morphological and compositional characterization. Optical properties have been studied by UV-Visible spectrophotometry and photoluminescence (PL) spectroscopy. Changing pH value from 4.8 to 0.8 decreases the particle size and correspondingly increases the band gap. The PL emission intensity also increases by decreasing the pH values.

Effect of pH Values on Conversion of Calcite Crystals into Calcium Phosphate Phases in Buffer Solutions

2007 ◽  
Vol 353-358 ◽  
pp. 2183-2186 ◽  
Author(s):  
Ya Ping Guo ◽  
Bao Qiang Li ◽  
Yu Zhou ◽  
De Chang Jia
Keyword(s):  
Calcium Phosphate ◽  
Ph Value ◽  
Octacalcium Phosphate ◽  
Precipitation Reaction ◽  
X Ray Diffraction ◽  
Buffer Solution ◽  
Effect Of Ph ◽  
X Ray ◽  
Buffer Solutions ◽  
Ph Values

Calcium phosphate phases with laminar-plate structure were converted from calcite powders after soaking in phosphate buffer solutions of pH’s 6.0-8.0 at 37 °C for 9 days. The effect of pH values on the conversion of calcite crystals was investigated by X-ray diffraction, scanning electron microscopy and Fourier-transform infrared spectroscopy. If the pH value of a buffer solution is kept at 6.0, calcite powders are converted mainly to dicalcium phosphate dehydrate (DCPD) or octacalcium phosphate (OCP). If the pH value is kept at 6.4 or 7.0, calcite powders are converted mainly to OCP. Hydroxyapatite (HAP) with poorly crystalline can be obtained from calcite powders both by treatment of a basic buffer solution, and by treatment of an acid buffer solution without regulating its pH value during the reaction. The conversion mechanism of calcite crystals is a dissolution-precipitation reaction.

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