• Title/Summary/Keyword: black-oxide

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Inhibitory Effect of Scorpion MeOH Extract on Nitric Oxide and Cytokine Production in Lipopolysaccharide - Activated Raw 264.7 Cells (전갈 메탄올추출물이 LPS로 유도된 Raw 264.7 cell에서의 nitric oxide 및 cytokine에 미치는 영향)

  • Choi, Jun-Hyeok;Lee, Jong-Rok;Jee, Seon-Young;Kim, Sang-Chan
    • Journal of Physiology & Pathology in Korean Medicine
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    • v.21 no.3
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    • pp.721-727
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    • 2007
  • Scorpion (SCP) has been clinically used for the treatment of endogenous wind to relieve convulsion, clearing away toxins, resolving hard masses and removing obstruction in the collaterals to relieve pain. Recent studies showed that scorpion toxins that affect the activating mechanism of sodium channels and indian black scorpion venom induced anti-proliferative and apoptogenic activity against human leukemic cell lines U937 and K562. There is lack of studies regarding the effects of SCP on the immunological activities. The present study was conducted to evaluate the effect of SCP on the regulatory effects of cytokines and nitric oxide (NO) for the immunological activities in Raw 264.7 cells. After the treatment of SCP MeOH extract dissolved in media for 1 h prior to the addition of lipopolysaccharide (LPS: 1 ${\mu}$g/ml), cell viability was measured by MTT assay, NO production was monitored by measuring the nitrite content in culture medium. Inducible nitric oxide synthase (iNOS) was determined by immunoblot analysis, and levels of cytokine were analyzed by sandwich immunoassays. As results, SCP inhibited the production of nitrite and nitrate (0.3 and 1.0 mg/ml), iNOS and p-$I_KB_{\alpha}$ protein, tumor necrosis factor-${\alpha}$ (0.3 and 1.0 mg/ml), interleukin-1${\beta}$ (0.3 and 1.0 mg/ml) and interleukin-6 (1.0mg/ml) in Raw 264.7 cells activated with LPS. These findings suggest that SCP can produce anti-inflammatory effect, which may play a role in adjunctive therapy in Gram-negative bacterial infections.

Transparent Conductive Single-Walled Carbon Nanotube Films Manufactured by adding carbon nanoparticles

  • Lee, Seung-Ho;Kim, Myoung-Soo;Goak, Jung-Choon;Lee, Nae-Sung
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2009.06a
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    • pp.417-417
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    • 2009
  • Although a transparent conductive film (TCF) belongs to essential supporting materials for many device applications such as touch screens, flat panel displays, and sensors, a conventional transparent conductive material, indium-tin oxide (ITO), suffers from considerable drawback because the price of indium has soared since 2001. Despite a recent falloff, a demand of ITO is expected to increase sharply in the future due to the trend of flat panel display technologies toward flexible, paper-like features. There have been recently extensive studies to replace ITO with new materials, in particular, carbon nanotubes (CNTs) since CNTs possess excellent properties such as flexibility, electrical conductivity, optical transparency, mechanical strength, etc., which are prerequisite to TCFs. This study fabricated TCFs with single-walled carbon nanotubes (SWCNTs) produced by arc discharge. The SWCNTs were dispersed in water with a surfactant of sodium dodecyl benzene sulfonate (NaDDBS) under sonication. Carbon black and fullerene nanoparticles were added to the SWCNT-dispersed solution to enhance contact resistance between CNTs. TCFs were manufactured by a filtration and transfer method. TCFs added with carbon black and fullerene nanoparticles were characterized by scanning electron microscopy (SEM), UV-vis spectroscopy (optical transmittance), and four-point probe measurement (sheet resistance).

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Reflectivity Improvement by Particle Neutralization in a Charged Particle-Type Electronic Display

  • Kim, Young-Cho
    • Transactions on Electrical and Electronic Materials
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    • v.14 no.1
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    • pp.36-38
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    • 2013
  • Eight sample panels using an indium tin oxide(ITO)-coated glass substrate were fabricated, with barrier ribs formed of 55 ${\mu}m$ height and 10 ${\mu}m$ width. The upper and lower substrates were designed with the same panel condition, so a cell gap of 110 ${\mu}m$ was obtained. The charged particles in a cell consisted of $TiO_2$ (for white color) or carbon black (black color), negative or positive charge control agents, and a polymer. The average diameter of the two types of particles was commonly 10 ${\mu}m$, and their q/m value was -4.5 ${\mu}C/g$ and +4.5 ${\mu}C/g$, respectively. The electrically opposite particles mixed by an agitator were loaded into their cells by a simple particle-loading method. The discharging process proceeded at a humidity of 80% and a temperature of $30^{\circ}C$. Reflectivity was measured depending on discharging time, and a hysteresis curve by bias voltage obtained for comparison between the neutralized and non-neutralized panel, in which the superior optical property of the neutralized panel was ascertained.

A Study on the Oxidation Reaction of Iron (II) Sulfate by Dry and Wet Process (황산제1철의 乾濕式에 의한 酸化反應에 對한 硏究)

  • Soo Duk Suhl;Joo Kyung Sung;Yong Kil Whang
    • Journal of the Korean Chemical Society
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    • v.21 no.2
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    • pp.121-124
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    • 1977
  • A study on the formation of black iron oxide was carried in differents of Fe(III), Fe(II) ion in the aqueous solution that iron(II) sulfate was calcined under various temperature and leached in water. The results obtained was follows; (1) It was found that the sample calcined in an electric muffle furnace maintained at $500^{\circ}C$ for 1 hour and leached in water was equivalent mole (Fe(III) /Fe(II) = 1) in 20% aqueous solution. (2) When the above mentioned solution was hydrolyzed at pH range of 7 to 8 for 2 hours at $100^{\circ}C$, 93% and over of iron was recovered in the form of ${\alpha}-Fe_3O_4$ with a black colour.

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Preliminary study for aging of latent fingerprints on nonporous substrate

  • Nam Yee Kim;Woo-Yong ParK;Jong Shin Park;Yuna Kim;Hee Sook Kim
    • Analytical Science and Technology
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    • v.36 no.2
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    • pp.80-88
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    • 2023
  • Fingerprints play a crucial role in the identification of potential suspects in criminal cases. However, determining the actual time, i.e., the time at which the fingermark was deposited, is challenging. Herein, we investigated the persistence and aging of fingerprints over time by observing the time evolution of latent fingerprints on a polystyrene box stored in a dark room. Fingerprint samples that were stored for up to two years could be detected with maximum accuracy using a black iron-oxide-based emulsion (black emulsion). To estimate the time of fingerprint deposition, fingerprint aging was studied by analyzing the lipid components of the fingerprints after their development. Cholesterol and squalene were selected as indicators of fingerprint aging, and their ratio was estimated to assess aging. In the case of fingerprint samples stored in a dark room for up to one month after deposition, the cholesterol/squalene ratio was approximately 0.01; it increased gradually to ≥ 0.1 over six months. A substantial reduction in the levels of cholesterol and squalene from the initial levels was also noted. Cholesterol and squalene were not detected after one year of storage. Thus, the extent of aging could be determined by analyzing the aging indicators for up to six months. Two cases that could cause error in the estimation of the fingerprint deposition time, namely, heating of the fingerprint sample before development and storage of the developed fingerprints in a dark room, were also investigated.

A Study on the Explosion Characteristics of by Product Gas of Carbon Black Manufacturing Process (카본블랙 제조 부생가스의 폭발 특성연구)

  • Oh Kyu-Hyung;Lee Sung-Eun
    • Journal of the Korean Institute of Gas
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    • v.10 no.3 s.32
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    • pp.60-64
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    • 2006
  • Explosion range and explosion characteristics of by product gas from carbon black manufacturing process were studied. About 75% of the by product gas were composed with water vapour and nitrogen. And the combustible component in the gas were hydrogen, methane, acetylene and carbon mono-oxide. Because of the combustible components in the by product gas there are explosion hazards in the gas handling process. Explosion range of the gas by experiment was from 17.1% to 70.7% and the value has considerable difference with the calculated value from Lechatelier law. Explosion pressure of the gas was $5.4kg/cm^2$ and the average explosion pressure rise rate was $39.2kg/cm^2/s$. Based on the experimental result we can expect that a explosion or fire accident during the handling the gas can make a severe loss, therefore there should be a explosion prevention or protection measures in the gas handling process.

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The Protective Effect of Black Ginseng Against Transient Focal Ischemia-induced Neuronal Damage in Rats

  • Park, Hyun-Jung;Shim, Hyun-Soo;Kim, Kyung-Soo;Shim, In-Sop
    • The Korean Journal of Physiology and Pharmacology
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    • v.15 no.6
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    • pp.333-338
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    • 2011
  • Black ginseng (BG) has been widely used as herbal treatment for improving physiological function. In order to investigate the neuroprotective action of this herbal medicine, we examined the influence of BG on the learning and memory of rats using the Morris water maze, and we studied the effects of BG on the central cholinergic system and neural nitric oxide synthesis in the hippocampus of rats with neuronal and cognitive impairment. After middle cerebral artery occlusion was applied for 2h, the rats were administered BG (100 or 400 $mgkg^{-1}$, p.o.) daily for 2 weeks, followed by training and performance of the Morris water maze test. The rats with ischemic insults showed impaired learning and memory on the tasks. Treatment with BG produced improvement in the escape latency to find the platform. Further, the BG groups showed a reduced loss of cholinergic immunoreactivity and nicotinamide adenine dinucleotide phosphate-diaphorase (NADPH-d)-positive neurons in the hippocampus compared to that of the ISC group. These results demonstrated that BG has a protective effect against ischemia-induced neuronal and cognitive impairment. Our results suggest that BG might be useful for the treatment of vascular dementia.

Synthesis of nano porous indium tin oxide by sol-gel combustion hybrid method (졸겔 연소법에 의한 nano crystalline ITO제작 및 특성)

  • Jung, Ki-Young;Kwak, Dong-Joo;Sung, Youl-Moon;Park, Cha-Soo
    • Proceedings of the KIEE Conference
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    • 2009.07a
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    • pp.1328_1329
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    • 2009
  • Nano porous indium tin oxide (ITO) powder was synthesized employing a new route sol-gel combustion hybrid method using Ketjen Black as a fuel. The nano porous ITO powder was composed of $SnCl_4$-98.0% and $In(NO_3)_3{\cdot}XH_2O$-99.999%, produce with a $NH_4OH$ with sol-gel method as a catalyst [1,2]. Crystal structures were examined by powder X-ray diffraction (XRD), and those results show shaper intensity peak at $25.6^{\circ}(2{\Theta})$ of $SnO_2$ by increased sintering temperature. A particle morphology as well as crystal size was investigated by scanning electron microscopy(FE-SEM), and the size of the nano porous powder was found to be in the range of 20~30nm. ITO films could controlled by nano porous powder at various sintering temperature in this paper[3,4]. The sol-gel combustion method was offered simple and effective route for the synthesis of nano porous ITO powder[5].

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The Effect of Coloring Condition on the Surface Characteristic of 304 Stainless Steel (304 스테인리스강의 착색 처리 조건이 표면 특성에 미치는 영향)

  • Kim, Ki-Ho
    • Journal of the Korean institute of surface engineering
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    • v.44 no.5
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    • pp.220-225
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    • 2011
  • 304 stainless steel plate was colored by hot dip and electrochemical treatment in a solution containing sulphuric and chromic acids. In the process, treatment variables such as operating time and methode were changed. The surface characteristics that changed by the treatment of the samples such as surface composition, oxide film thickness, color, surface roughness and reflectivity were studied. Surface composition was varied as follows. Fe was decreased, but Cr and O were increased. Ni was increased until 20 min, but reveals decreasing tendency as time passed after that. These means the surface film becomes chrome rich oxide phase as the treatment times increase. The thickness of film was about 220 nm at 30 min by dip treatment and it reduced as the treatment times increased. On the other hand, the thickness was about 150 nm at 10 min by electrochemical method and it doesn't increased with time. Surface color changed from metallic white of the base plate to gray, black, red, and green-blue, gradually, as the treating time increased. The reflectivity of colored surface measured by UVVIS-NIR spectrophotometer was reduced from max 38% of basis metal to min 3.5%.

Highly Durable Pt catalyst Supported on the Hybrid Carbon Materials for Polymer Electrolyte Membrane Fuel Cell (탄소계 복합담지체에 담지된 고내구성 고분자전해질 연료전지용 백금촉매)

  • Park, Hyang Jin;Hur, Seung Hyun
    • Journal of the Korean Electrochemical Society
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    • v.17 no.3
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    • pp.201-208
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    • 2014
  • A Pt catalyst ($Pt/G_xC_y$) supported on the hybrid supporting materials composed of graphene oxide (GO) and carbon black (C) was fabricated using polyol method to improve the durability of electrocatalysts. The electrochemical performances measured by cyclic voltammograms using three-electrode system revealed that the properly designed $Pt/G_xC_y$ catalyst exhibited higher durability than that of Pt/C catalyst without sacrificing an electrocatalytic acivity. In the oxygen reduction reaction (ORR) performed in acid solution with the rotating disk electrode, the $Pt/G_xC_y$ catalyst showed greater mass and area-specific activity than those of Pt/C catalyst.