• Title/Summary/Keyword: Retention rate

Search Result 1,071, Processing Time 0.032 seconds

Preparation and capacitance properties of graphene based composite electrodes containing various inorganic metal oxides

  • Kim, Jeonghyun;Byun, Sang Chul;Chung, Sungwook;Kim, Seok
    • Carbon letters
    • /
    • v.25
    • /
    • pp.14-24
    • /
    • 2018
  • Electrochemical properties and performance of composites performed by incorporating metal oxide or metal hydroxide on carbon materials based on graphene and carbon nanotube (CNT) were analyzed. From the surface analysis by field emission scanning electron microscopy and field emission transmission electron microscopy, it was confirmed that graphene, CNT and metal materials are well dispersed in the ternary composites. In addition, structural and elemental analyses of the composite were conducted. The electrochemical characteristics of the ternary composites were analyzed by cyclic voltammetry, galvanostatic charge-discharge tests, and electrochemical impedance spectroscopy in 6 M KOH, or $1M\;Na_2SO_4$ electrolyte solution. The highest specific capacitance was $1622F\;g^{-1}$ obtained for NiCo-containing graphene with NiCo ratio of 2 to 1 (GNiCo 2:1) and the GNS/single-walled carbon $nanotubes/Ni(OH)_2$ (20 wt%) composite had the maximum specific capacitance of $1149F\;g^{-1}$. The specific capacitance and rate-capability of the $CNT/MnO_2/reduced$ graphene oxide (RGO) composites were improved as compared to the $MnO_2/RGO$ composites without CNTs. The $MnO_2/RGO$ composite containing 20 wt% CNT with reference to RGO exhibited the best specific capacitance of $208.9F\;g^{-1}$ at a current density of $0.5A\;g^{-1}$ and 77.2% capacitance retention at a current density of $10A\;g^{-1}$.

Rhodopsedomonas palustris P4를 이용한 Trickle Bed Reactor에서의 일산화탄소와 물로부터 연속적인 수소생산

  • Park, Ji-Yeong;Lee, Tae-Ho;Park, Seong-Hun
    • 한국생물공학회:학술대회논문집
    • /
    • 2000.11a
    • /
    • pp.241-244
    • /
    • 2000
  • Continuous $H_2$ production from CO and water was studied in a trickle bed reactor(TBR) using Rhodopspedomonas palustris P4. To achieve high cell density, R. palustris P4 were cultivated by a fed-batch culture mode under chemoheterotrophic and aerobic condition, and final cell concentration was 13 g/L. TBR could provide sufficient residence time for CO to contact with cell suspension circulating TBR. The maximum CO uptake rate was found to be 16 mmol/L/hr at gas retention time of 50 min and CO partial pressure of 0.4 atm. In our correlation of the experimental data with mathematical model of TBR, the TBR operation with P4 was found to be lie in an intermediate state between mass transfer limitation and kinetic limitation. Due to the high cell density as well as hydrogen production activity in this study, TBR operation showed a superior performance to other previous reports on microbial hydrogen production.

  • PDF

A Literature Study of Senile Constipation (노인(老人) 변비(便秘)에 대(對)한 문헌적(文獻的) 고찰(考察))

  • Jeong, Chang-Hwan;Shin, Hyeon-Chul;Jeong, Ji-Cheon
    • The Journal of Internal Korean Medicine
    • /
    • v.16 no.1
    • /
    • pp.40-61
    • /
    • 1995
  • This study was performed to investigate concept, systoms, causes of disease, pathogenic mechanisms, therapies and precriptions about senile constipation through the successive medical literature, recent chinese medical literature and chinese medical joumals. Senile constipation seems to be applicable to dryness syndrom and constipation of insufficiency type, have something to do with kidney(the most), lung, spleen and large intestine. The most principal cause of disease is yin-fluid, the rest deficiency of qi, insufficiency of yang, stagnation of qi and retention of fever etc. There are enriching the blood and moistening dryness in principal therapy, the rest are invigorating qi and loosing the bowel, warming and invigorating the spleen and kidney, regulating the flow of qi and promoting the stagnancy of qi and expelling the pathogenic heat etc. In prescriptions there are Yunjangtang, Jengaektang, Hwanggitang, Jechunjeon, Yukmatang and Majainhwan as the causes of disease, meanwhile are Yungjang-tang, Jechunjeon and Majainhwan in the vulgaris prescriptions. And in medical herbs there are nourishing yin medicines as Rhizoma rehmanniac, Radix ophiopogonis and Radix scrophulariae etc., invigorating qi medicines as Radix astragali, Radix codonopsitis and Radix polygoni multiflori etc, invigorating yang medicines as Caulis cistanchis and Semen psoraleae etc., promoting qi circulating medicines as Radix saussurea, Lignum aquilariae and Radix linderae etc., and reducing fever and therapeutic method to keep the adverse qi flowing downward medicines as Semen cannabis, Rhizoma rhei, Fructus immaturus ponciri, and Cortex magnoliae etc.. Meantime Rhizoma rehmanniae, Radix ophiopogonis, Caulis cistanchis, Radix angelicae gigantis, Semen cannabis, Semen biotae, Semen pruni japonicae and Semen persicae in principal herb-medicines. In clinical reports the process of disease was between 10 to 20 years, the evacuation cycle between 4 to 7 days, generally possessed chronic diseases as hypertension, diabetes, arteriosclerosis and cerebro- vascular disorders etc. and the efficiency rate was more than 90%. The senile constipation is occured in succession or promoted by chronic diseases as obesity, hypertension, diabetes, arteriosclerosis. hrperlipemia, cerebro- vascular disorders etc., so diet-regulating, adequate exercise, proper evacuation-habit and psychologic rest etc. are important more than medicine-treatments.

  • PDF

Quantitative Analysis of Glycyrrhizic Acid in Fermented Glycyrrhizae Radix by HPLC (HPLC를 이용한 발효 감초의 지표 성분 분석)

  • Um, Young-Ran;Shim, Ki-Shuk;Lee, Jae-Hoon;Park, Hwa-Yong;Ma, Jin-Yeul
    • Korean Journal of Oriental Medicine
    • /
    • v.15 no.1
    • /
    • pp.85-89
    • /
    • 2009
  • The aim of this study was to study the quantitative analysis of glycyrrhizic acid in Glycyrrhizae Radix extract fermented with Paecilomyces japonica, Ganoderma lucidum, honey or Nuruk. The amounts of dry on loss were measured and the quantitative analysis of glycyrrhizic acid was performed by high performance liquid chromatographic (HPLC). HPLC method was performed on C18 column ($250\;mm\;{\times}\;4.6\;mm$, $5\;{\mu}m$, RS tech) using gradient solvent mixtures of water-acetonitrile with photodiode array detector (254 nm). The flow rate was $1.0\;m{\ell}/min$. Retention time of glycyrrhizic acid was about 23.96 min and linearity of calibration was $R^2$=0.9998. Contents of glycyrrhizic acid in Glycyrrhizae Radix extract (control) was $5.048\;{\pm}\;0.14$; Contents of glycyrrhizic acid in Glycyrrhizae Radix extract fermented with Paecilomyces japonica (SDT) was $1.975\;{\pm}\;0.07$; Contents of glycyrrhizic acid in Glycyrrhizae Radix extract fermented with Ganoderma lucidum (SYT) was $2.676 \;{\pm}\;0.07$; Contents of glycyrrhizic acid in Glycyrrhizae Radix extract fermented with honey (SST) was $5.191\;{\pm}\;0.06$; Contents of glycyrrhizic acid in Glycyrrhizae Radix extract fermented with Nuruk (SNT) was $5.305\;{\pm}\;0.34$, respectively. Contents of glycyrrhizic acid in SDT and SYT were decreased but that in SST and SNT was increased when compared to control.

  • PDF

Growth Response on the Euonymus fortunei 'Emelad' n 'Gold' as affected by Artificial Plantings Soil Properties during Dry Spring Season (봄철 건조기 용기형 벽면녹화에서 식재지반 조성에 따른 황금줄사철의 적응성)

  • Ju, Jin-Hee;Kim, Hea-Ran;Park, Heon;Yoon, Yong-Han
    • Journal of Environmental Science International
    • /
    • v.23 no.7
    • /
    • pp.1299-1305
    • /
    • 2014
  • For evaluating the effect of various artificial planting soil properties on the Euonymus fortunei 'Emelad'n Gold' growth, a container green wall system experiment was conducted in a wall of greenhouse at Konkuk University, Glocal campus. The experimental artificial planting grounds were prepared with different organic soil conditioner ratios (Control, $A_4O_1$, $A_2O_1$ and $A_1O_1$) and with drought tolerance and an ornamental value Euonymus fortunei 'Emelad'n Gold' was planted. The soil and plant characteristics were investigated from April to Jun 2010. The volumetric soil moisture contents were significantly increasing order as the amount of organic soil conditioner level increased in order to $A_1O_1$ > $A_2O_1$ > $A_4O_1$ > Control. At 4 treatment, soil chemical properties were inversely related to organic soil container ratios increase. The differences of root collar caliper, number of branch, and survival rate between the organic soil conditioner ratio were not significantly affected by organic soil conditioner. But, plant height, internode length, leaf length and leaf width were significantly shorter on plants planted $A_1O_1$ than plants planted other treatments. Therefore, Euonymus fortunei 'Emelad'n Gold' had good growth response regardless of organic soil conditioner ratio and the plant is expected to be a highly valuable shrub for the green wall system if it should be considered in integration with stormwater retention or as a soil conditioner for increasing soil water contents in artificial planting soil.

Clinical and radiographic assessment of narrow-diameter and regular-diameter implants in the anterior and posterior jaw: 2 to 6 years of follow-up

  • Alrabiah, Mohammed;Deeb, Modhi Al;Alsahhaf, Abdulaziz;AlFawaz, Yasser F.;Al-Aali, Khulud Abdulrahman;Vohra, Fahim;Abduljabbar, Tariq
    • Journal of Periodontal and Implant Science
    • /
    • v.50 no.2
    • /
    • pp.97-105
    • /
    • 2020
  • Purpose: The present retrospective clinical study aimed to evaluate and compare the clinical and radiographic parameters, complications, and satisfaction in patients who received fixed prostheses supported by narrow-diameter implants (NDIs) in the anterior and posterior jaw. Methods: Patients aged ≥30 years who had NDI-supported fixed prostheses in the anterior or posterior region of either jaw for at least 2 years were included. Complications such as chipping of the crown; loosening or fracture of the screw, crown abutment, or implant; and loss of retention were recorded. Clinical peri-implant outcomes and crestal bone loss (CBL) were measured. A questionnaire was used to record responses regarding the aesthetics and function of the fixed restorations. Analysis of variance was used to assess the significance of between-group mean comparisons. The log-rank test was performed to analyze the influence of location and prosthesis type on technical complications. Results: Seventy-one patients (mean age: 39.6 years) provided informed consent with a mean follow-up duration of 53 months. Only bleeding on probing showed a statistically significant difference between NDIs in the anterior and posterior regions. The complication rate for NDIs in the posterior region was significantly higher than that for NDIs in the anterior region (P=0.041). For NDIs, CBL was significantly higher around splinted crowns than single crowns (P=0.022). Overall mean patient satisfaction was 10.34±3.65 on a visual analogue scale. Conclusions: NDIs in the anterior and posterior jaws functioned equally well in terms of periimplant soft and hard tissue health and offered acceptable patient satisfaction and reasonable complication rates.

EXCISIONAL BIOPSY OF MUCOCELE USING BIOPSY PUNCH (생검펀치를 이용한 점액낭종의 절제)

  • Hong, Eun-Hye;Choi, Byung-Jai;Lee, Jae-Ho;Choi, Hyong-Jun;Son, Heung-Kyu;Kim, Seong-Oh
    • Journal of the korean academy of Pediatric Dentistry
    • /
    • v.34 no.2
    • /
    • pp.349-353
    • /
    • 2007
  • Mucocele is a clinical term of the localized superficial mucosal swelling caused by salivary retention after the obstruction or the rupture of minor salivary ducts. Various treatment methods have been suggested to lower its recurrence rate, including complete excision of lesion Biopsy punch can be used easily and simply for complete excision of mucocele. It has several advantages, such as convenience in use, low bleeding tendency, and nearly no requirements for post-operative management. In this case, biopsy punch was used for the removal of mucocele in an uncooperative child, which enable fast, simple and safe procedure, with a good result.

  • PDF

Effects of the Dietary Inclusion of Porphyra and Sea Tangle Laminaria japonica on the Growth, Feed Utilization, Body Composition, and Plasma Chemistry of Juvenile Korean Rockfish Sebastes schlegeli (사료내 김(Porphyra)과 다시마(Laminaria japonica) 첨가가 조피볼락(Sebastes schlegeli) 치어의 성장, 사료 이용성, 체조성 및 혈액 성상에 미치는 영향)

  • Jeon, Gyu Ho;Cho, Sung Hwoan;Lee, Sang Min;Nam, Taek Jeong;Kim, Dong Soo
    • Korean Journal of Fisheries and Aquatic Sciences
    • /
    • v.46 no.5
    • /
    • pp.546-551
    • /
    • 2013
  • This study examined the effects of the dietary inclusion of Porphyra and sea tangle Laminaria japonica on the growth, feed utilization, body composition, and plasma chemistry of juvenile Korean rockfish Sebastes schlegeli. Eight hundred and forty juvenile fish averaging 5.0 g were allocated 40 fish per tank to 21 180-L flow-through tanks. Seven experimental diets were prepared: control (Con) without additive, 0.5 and 1% Porphyra extract (PE), 3% Porphyra powder (PP), 0.5 and 1% sea tangle extract (STE) and 3% sea tangle powder (STP), referred to as PE-0.5, PE-1, PP-3, STE-0.5, STE-1, and STP-3, respectively. Each additive was included in the experimental diet at the expense of the same amount of wheat flour. Each experimental diet was fed to triplicate groups of fish. The experimental diets had no effect on the survival, weight gain or specific growth rate of the fish, feed consumption, feed efficiency ratio, protein efficiency ratio, protein retention, hepatosomatic index, condition factor, moisture or crude protein content of the entire body excluding the liver or moisture, crude protein or crude lipid content of the liver. None of the plasma parameters were affected by the experimental diets. Based on these results, the dietary inclusion of Porphyra and sea tangle did not affect the growth, feed utilization, body composition or plasma chemistry of juvenile Korean rockfish.

Toxicity of Hematoporphyrin-Coated Magnetic Ferrofluid in Rats

  • Hwang Youn-Hwan;Lim Jong-Hwan;Park Byung-Kwon;Kim Myoung-Suk;Kim Chong-Oh;Yun Hyo-In
    • Toxicological Research
    • /
    • v.22 no.1
    • /
    • pp.55-59
    • /
    • 2006
  • The purpose of this study was to investigate the toxicity of hematoporphyrin-coated magnetic ferrofluid (HP-MF) through intravenous administration in Sprague-Dawley rats. Each group was treated with either saline, or the HP-MF at 0.5, 1, 1.5, 2 and 4 ml/kg body weight (b.w.) for the observation of survival rate, clinical symptoms, laboratory values and histopathological findings. In this study, HP-MF was evaluated for the survival rates, symptoms, laboratory values and histopathological examination after treatments. The result revealed that the animals in the group of HP-MF at 2 and 4 ml/kg b.w. showed some lethality. In serum biochemistry, the levels of AST, ALT and ALP were increased in the MF and HP-MF treated groups. However, histopathological examination for the suspected organs showed no evidence of hepatotoxicity and nephrotoxicity of typical iron poisoning. Though the toxicity of HP-MF was higher than that of HP, long retention of hematoporphyrin via HP-MF provides additional benefit over conventional hematoporphyrin. HP-MF could be utilized as a potential photodynamic agent in cancer therapy. It is suggested to develop an efficient external magnetic device to attract hematoporphyrin in the target site, thereby enabling to administering a small amount of HP-MF.

Effect of Ozone Injection on Dewaterability and Thickening of Sewage Sludge (하수 슬러지 농축 및 탈수성에 미치는 오존의 영향)

  • Hwang, Kyeoung-Sa;Kim, Moon-Ho;Bae, Yoon-Sun;Park, Chul-Hwi
    • Journal of Korean Society of Water and Wastewater
    • /
    • v.19 no.6
    • /
    • pp.800-808
    • /
    • 2005
  • It is required to propose an alternatives for appropriate sludge treatment owing to persistent construction of sewage treatment plant and increase of sewage sludge quantity. In order to treat sludge more efficiently, the methods which reduce the cost of sludge treatment have been studied such as sludge reduction and conditioning. Especially ozone treatment reduces solid quantity and improves separation of solid-liquid at the same time. Therefore ozone treatment have a positive effect on reduction and stabilization of sludge. So, this study applied ozone to sewage sludge and induced cell destruction of sludge. By comparing with the correlation between thickening and dewatering, and evaluating moisture content and solubilization of cake, this study verificates the effect of process improvement for ozone pre-treatment. In J-STP case, according to ozone dose solid flux increased about 12 times from $1kg/m^2{\cdot}h$ to $12kg/m^2{\cdot}h$. Also this plant were capable to shorten thickening time from 40 minutes to 6~7 minutes. Thus it is expected to reduce volume and retention time of thickener. On pH effect factor, dewatering at pH4 was more than at pH11, $3.05{\times}10^{11}$ and $3.82{\times}10^{11}(m/kg)$. But effect of pH was analogous to ozone, $2.81{\times}10^{11}(m/kg)$. The effect of pH on thickening was similar to law sludge, $0.68(kg/m^2{\cdot}h)$, and the effect of ozone injection on thickening was the biggest, $3.45(kg/m^2{\cdot}h)$. The COD solubilization rate improved from about 5 to 30%. So it is judged that we are able to utilize most solubilized sludge to another sewage treatment plants.