Locharoenrat, Kitsakorn

Preferred name

Alternative Name

LOCHAROENRAT, KITSAKORN

Locharoenrat, K.

Main Affiliation

School of Science

kitsakorn.lo@kmitl.ac.th

Now showing 1 - 10 of 32

Some of the metrics are blocked by your
consent settings
Rhodamine 6G and Au–Pd core–shell nanorods: Fluorescence enhancement for detection of mercury
(2018-01-01)
Rammarat, Ekkachai
;
Kraithong, Sasiwimon
;
Wanichacheva, Nantanit
;
Swanglap, Pattanawit
;
Yindeesuk, Witoon
We show that hybrid organic–inorganic particles are efficient for accurate sensing of mercury ions and following up trace amounts of the mercury pollutions spread in the environment. The process of synthesis of a working substance starts from preparation of rhodamine 6G derivative. Then the dye molecules are bound on the surface of Au–Pd core–shell nanorods. Mercury ions with different concentrations are finally attached onto this fluorescence sensor. Fluorescence emission of the sensor is detected with a luminescence spectrophotometer. The experimental results demonstrate that the fluorescence intensity of one of our sensors, a sensor B, is remarkably enhanced when the mercury-ion concentration increases from 0 to 15.5 µM. The limit of detection of the ions is as low as 20.6 nM. The working mechanism of our fluorescence sensor can be explained through the fluorescence-energy transfer and the plasmonic effect associated with spirolactam forms of rhodamine and conducting bimetallic nanoparticles.
Some of the metrics are blocked by your
consent settings
Enhancement of fluorescence in inorganic dyes by metallic nanostructured surfaces
(2016-01-01)
Locharoenrat, Kitsakorn
;
Damrongsak, Pattareeya
We have studied the influence of shape and chemical content of metallic nanostructures (gold-palladium core-shell nanorods, gold nanobipyramids and single-crystalline porous palladium nanocrystals) on the luminescence of Rhodamine 6G and Coumarin153 dyes. The changes found in the emission intensity are attributed to different proportions of the dyes and the metallic nanostructures. The enhancement of the fluorescence observed by us for the cases of Rhodamine 6G with gold-palladium core-shell nanorods and Rhodamine 6G with gold nanobipyramids suggests their promising plasmonic properties. This may be regarded as a preliminary step towards development of the fluorescent probes possessing high photo-sensitivity.
Some of the metrics are blocked by your
consent settings
Removal of metals using a ZnO/Au composite under visible-light illumination
(2018-01-01)
Thonglim, P.
;
Sirivichai, M.
;
Thanjai, O.
;
Locharoenrat, K.
Gold nanoparticles embedded into a ZnO film are prepared with a simple spin-coating technique. Photocatalytic performance of the film is studied under irradiation with the visible light. We suggest to increase the amount of Au nanoparticles in the ZnO matrix (from 0 to 400 mg in our particular case) to improve photocatalytic efficiency of the film via a combination of plasmonic-resonance and Schottky-barrier effects. We choose Fe<sup>2+</sup> as a model representative of metals available in the wastewater. It is demonstrated that the ZnO/Au films with increased Au content reduce efficiently the amount of ferrum ions in the water solution. In particular, the film with the content ratio ZnO:Au = 1:2 serves as a good absorber for removing Fe<sup>2+</sup> in case if their initial concentration is equal to 0.2 mM.
Some of the metrics are blocked by your
consent settings
Optical studies of zinc oxide nanoparticles and their biomedical application
(2015-01-01)
Locharoenrat, Kitsakorn
;
Srivatcharakul, Suttijit
Zinc oxide nanoparticles are prepared using the pulsed laser ablation approach (Nd:YAG laser at a central wavelength of 1064 nm with the pulse energy of 100 milli-joules) of the zinc metal plate immersed in a solution of sodium dodecyl sulfate at the ambient temperature. The laser fluence dependence of absorbance of the produced nanoparticles shows a single and sharp peak around 375 nm, indicating that the nanoparticles have a narrow size (45 - 60 nm) with almost spherical shape. Next, zinc oxide nanoparticles with different concentrations can hold promise in the phototoxic effect. The photocatalysis activity of the zinc oxide nanoparticles can considerably enhance the injury of a cancer cell mediated by the reactive oxygen species.
Some of the metrics are blocked by your
consent settings
Second harmonic generation based on strong field enhancement in metallic nanostructured surface
(2014-01-01)
Locharoenrat, Kitsakorn
Although absorption is still the primary optical property of interest, other spectroscopic techniques including optical second harmonic generation (SHG) are also used to understand anisotropic nature of nanomaterials. Benefit of SHG technique as compared with linear optical approach is that SH response is the most sensitive to surface potential changes and SH intensity mainly comes from surface/interface layers. This article reports that optical absorption spectra due to surface plasmon modes of metallic nanowires exhibit strong anisotropic absorption. Maxwell-Garnett simulation cannot fit with experimental results because of wire sizes much larger than wavelength of light, whereas finite-difference timedomain calculation can fit well with experimental findings in terms of position of photon energy of absorption peak with respect to polarization conditions.
Some of the metrics are blocked by your
consent settings
Calculation of Lead-Iron Double-Layer Thickness for Gamma-Ray Shielding by MATLAB Program
(2017-01-01)
Lekchaum, Sarai
;
Locharoenrat, Kitsakorn
This contribution is aimed at designing the optimal thickness of lead-iron double-layer container to store a radioactive waste releasing the photon energy at 1.3325 MeV and initial radiation intensity at 100 mSv/hr using the optimization design by MATLAB software. This design consisted of three parts of calculations to achieve 1000 times the radiation attenuation of container. The first was the logarithmic interpolation for the mass attenuation coefficient. The second was the bilogarithmic interpolation for the exposure buildup factor. The third was the contour-plotting analytical technique for the optimal thickness of radiation container. The values of mass attenuation coefficient and exposure buildup factor were exactly validated as compared with the standard reference database. Furthermore, we have found that the optimal thickness was 3.2 cm for lead (1st layer) and 17.0 cm for iron (2nd layer). Container weight was 994.30 kg, whilst container cost was 167.30 USD. The benefit of our design can quickly and precisely apply for the radiation safety assessment of the occupational radiation workers who always work in the nuclear reactor area.
Some of the metrics are blocked by your
consent settings
Use of Ag-Au-ICG to increase fluorescence image of human hepatocellular carcinoma cell lines
(2023-01-01)
Sittisart, Pattarapol
;
Locharoenrat, Kitsakorn
Indocyanine green (ICG) is effective for a variety of applications including liver tumour imaging and operates in the near-infrared window. Agents for near-infrared imaging are, however, still in clinical development. The present study aimed to prepare and investigate fluorescence emission properties of ICG in combination with Ag-Au in order to enhance their specific interactions with human hepatocellular carcinoma cell lines (HepG-2). The Ag-Au-ICG complex was prepared via physical adsorption, and hence evaluated for fluorescence spectra using a spectrophotometer. Ag-Au-ICG at an optimised dosage (Ag-Au:ICG = 0.0147:1 molar ratio) in Intralipid medium was added to HepG-2 to observe the maximum fluorescence signal intensity, which further enhanced HepG-2 contrast fluorescence. Ag-Au-ICG served as a fluorescence enhancer bound onto the liposome membrane, whilst free Ag, Au, and pure ICG induced low levels of cytotoxicity in HepG-2 and a normal human cell line. Thus, our findings provided new insights for the liver cancer imaging.Highlights Concentration-dependent fluorescence peaking in the near-infrared window revealed ICG aggregation in Ag-Au molecules. Ag-Au-ICG fluorescence intensity depended strongly on the environmental media. Human hepatocellular carcinoma cell lines treated with Ag-Au-ICG in Intralipid enhanced the contrast of fluorescence microscopy images by decreasing the level of scattering in the cell lines with the contrast values being approximately five times those observed in pure ICG in Intralipid.
Some of the metrics are blocked by your
consent settings
Characteristic Evaluation of Organic Light-Emitting Diodes Prepared with Stamp Printing Technique
(2017-01-01)
Chittawanij, Apisit
;
Locharoenrat, Kitsakorn
We have reported on a stamp printing technique that uses PET release film as a printing stamp to deposit TPBi thin film served as the electron transport layer of the organic light-emitting diodes. TPBi thin film was printed with a good uniformity and resolution. Effect of deposition conditions on optical and electrical properties and surface roughness of TPBi thin film have been studied under spectroscopy and atomic force microscopy, respectively. It is found that characteristic of TPBi thin film is improved via controlled stamp temperature and time. Since TPBi thin film exhibits the surface morphology comparable to that of conventional spin-coating thin film, our findings suggest that PET release film-based stamp printing approach is possible to use as an alternative deposition of the organic thin film as compared with a traditional one.
Some of the metrics are blocked by your
consent settings
Design of dual flywheels with connecting rods for gamma-type Stirling engine
(2018-01-01)
Lekchaum, S.
;
Locharoenrat, K.
A gamma-type Stirling engine, based on a dual flywheels’ concept, was designed and fabricated. Optimized design of the engine, with connecting rods, was introduced to achieve a steady state of the Stirling engine cycle. Performances of the engine were therefore presented in terms of piston motion, inertia force, angular speed, pressure-volume diagram and temperature difference. It was found that optimum length of 45 mm from the connecting rod was able to reach the maximum output mechanical speed of 738 rpm at the maximum inertia force of 0.5 N. The engine offered thermal efficiency of 46.15% and total output power of 1.21 W under the temperature difference of 267 K. In the future, this design is expected to prove useful for applications in portable generators.
Some of the metrics are blocked by your
consent settings
Preparation and heavy metal removal from chitosan composite
(2016-06-01)
Locharoenrat, Kitsakorn
Recently the removal of trace element using biodegradable polymers is important. This paper involves preparation and evaluation of chitosan/polyethylene glycol blend served as a heavy metal removal system. The author prepared various blending system with different composition ratios and different crosslinking density. Experimental results indicated that swelling degree and thermal property of the blend film were correlated with blend ratio and crosslink density. The blend film was then investigated its metal-binding performance. Copper sorption capacity was one of major potential applications in a field of wastewater treatment.

Locharoenrat, Kitsakorn

Filters

Settings

Sort By

Results per page