• 펄프종이기술
• /
• 제48권3호
• /
• pp.37-43
• /
• 2016

Various mechanical and chemical pretreatment methods including alkali treatment, pre-beating, enzyme treatment and oxidation treatment have been used to reduce the production energy of the microfibrillated cellulose (MFC). Among them, alkali swelling can be helpful to reduce the energy consumption because the internal bonding between fibrils could be weakened. In this study, dimethyl sulfoxide (DMSO) was used as a cosolvent to improve alkali pretreatment efficiency and the effects of NaOH concentration during NaOH-DMSO swelling on changes in fiber characteristics of softwood bleached kraft pulp (SwBKP) were elucidated. For alkali treatment in H2O-DMSO solvents, fiber length were decreased with increasing NaOH concentration while fiber width, curl and WRV were increased. WRV began to increase at 8% NaOH solution. In addition, above 8% concentration of NaOH, crystalline structure of pulp fibers converted from cellulose II to cellulose III by DMSO cosolvent. Comparing the previous results with this study, it was shown that DMSO cosolvent could promote swelling of pulp fibers and thus reduce NaOH concentration for the maximum swelling of fibers.

• 한국식생활문화학회지
• /
• 제29권5호
• /
• pp.415-420
• /
• 2014

This study was conducted to establish optimum conditions for coagulation of konjac jelly as well as antimicrobial activity by concentration of $Ca(OH)_2$. Hardness, gumminess, and chewiness of konjac jelly increased according to concentration of konjac powder, the key material of konjac jelly. The highest sensory evaluation score was acquired with konjac jelly made with 3% konjac powder. A $Ca(OH)_2$ concentration of 0.4-0.6% as a coagulation agent was optimum for coagulation of konjac jelly. Further, sensory score was highest at a $Ca(OH)_2$ concentration of 0.6%. All populations of bacteria, yeast, and mold in konjac jelly were restrained by $Ca(OH)_2$ in a concentration- dependent manner. Furthermore, all tested microorganisms were strictly restrained at $1.0{\times}10^{-2}$ N of $Ca(OH)_2$.

• 한국재료학회지
• /
• 제26권10호
• /
• pp.513-520
• /
• 2016

The effect of NaOH concentration on the properties of electrolytic plasma processing (EPP) coating formed on AZ61A Mg alloy is studied. Various types of EPP were employed on magnesium alloy AZ61A in a silicate bath with different concentrations of NaOH additive. Analysis of the composition and structure of the coating layers was carried out using an X-ray diffractometer (XRD) and a scanning electron microscope (SEM). The results showed that the oxide coating layer mainly consisted of MgO and $Mg_2SiO_4$; its porosity and thickness were highly dependent on the NaOH concentration. The Vickers hardness was over 900 HV for all the coatings. The oxide layer with 3 g/l of NaOH concentration exhibited the highest hardness value (1220 HV) and the lowest wear rate. Potentiodynamic testing of the 3 g/l NaOH concentration showed that this concentration had the highest corrosion resistance value of $2.04{\times}10^5{\Omega}cm^2$; however, the corrosion current density value of $5.80{\times}10^{-7}A/cm^2$ was the lowest such value.

• 대한기계학회:학술대회논문집
• /
• 대한기계학회 2001년도 춘계학술대회논문집D
• /
• pp.54-59
• /
• 2001

OH radical concentration have been measured in a methane-air partially premixed flames using PLIF. Excitation lines were selected $Q_{1}(6)$ branch, (1,0) band. The system is consisted of Nd:YAG laser, dye laser and frequency doubler to make pump beam for OH radical. On the direct photographs, flame height increases as fuel flow rate and equivalence ratio increase. And on the PLIF images, OH radical is distributed from premixed flame front to nonpremixed flame front through the flame structure with all equivalence ratio. OH overall concentrations increase with equivalence ratio. At the stoichiometric equivalence ratio, the peak of OH radical concentration exists strongly near the inner cone. As equivalence ratio is changed to richer, OH radical distribution goes thinly and the peak is increased as longitudinal direction. As the flow goes to the downstream, OH radical concentration decreases and broadens, because OH radical reacts with another species after OH formation at the initial oxidization. This phenomenon resembles radial distribution. At the l00cc fuel flowrate, the radial peak of OH radical exists from x/R=l.0 to 1.5.

• Bulletin of the Korean Chemical Society
• /
• 제32권12호
• /
• pp.4316-4320
• /
• 2011

The effects of various hydroxide compounds on base stacking (BS) were investigated for pre-concentration of DNA molecules in capillary electrophoresis (CE). In BS, hydroxide ions ($OH^-$) were electrokinetically introduced after DNA sample injection. A neutralization reaction occurred between the $OH^-$ and $Tris^+$ of the running buffer, which resulted in a zone of lower conductivity. Within the low conductivity zone of the high electric field, the DNA molecules moved more rapidly and were concentrated in front of the low conductivity zone. At the same BS conditions of CE, the enhanced sensitivity of the DNA samples was dependent on the kind of multivalent cations in the hydroxide compounds. Except for LiOH, the hydroxide compounds with monovalent cations showed more effective BS than those with divalent cations because of solubility, ionic strength and electronegativity. The order of hydroxide compounds that enhance the detection sensitivity of DNA molecules was as follows: NaOH > $NH_4OH$ > KOH > $Ba(OH)_2$ > $Sr(OH)_2$ > LiOH > $Ca(OH)_2$ > $Mg(OH)_2$. $NH_4OH$, KOH and $Ba(OH)_2$ proved to be efficient hydroxide compounds to use as effective BS reagents in CE instead of NaOH.

• 한방재활의학과학회지
• /
• 제21권1호
• /
• pp.23-33
• /
• 2011

Objectives : The present study investigated effects of Artemisia Capillaris Thunberg ethanol extract(EtOH ext). on lowering lipid, anti-oxidation and concentration of plasma inflammatory mediators using rat fed on high oxidized fat. Methods : We divided fat sprague-dawley rats fed on high oxidized into 4 groups. They were normal group, feed with 100 mg/kg Artemisia Capillaris Thunberg group, feed with 200 mg/kg Artemisia Capillaris Thunberg group and feed with 300 mg/kg Artemisia capilaris Thunberg group. They were administered for 4 weeks. We measured concentration of plasma free fatty acid(FFA), plasma triglyceride, plasma total cholesterol, and plasma low density lipoprotein-cholesterol(LDL-cholesterol), plasma high density lipoprotein-cholesterol(HDL-cholesterol), concentration of liver total cholesterol and liver triglyceride (TG), concentration of plasma thiobarbituric acid reactive substance(TBARS) and liver thiobarbituric acid reactive substance(TBARS), glutathione peroxidase (GSH-Px) activity, superoxide dismutase(SOD) activity and catalase(CAT) activity, plasma nitric oxide(NO), ceruloplasmin and ${\alpha}-glycoprotein$. Results : 1. The Artemisia Capillaris Thunberg EtOH ext. groups showed low concentration of plasma FFA, plasma triglyceride, plasma total cholesterol and plasma LDL-cholesterol compared to control group. However, concentration of plasma HDL-cholesterol was increased in the Artemisia Capillaris Thunberg EtOH ext. groups. 2. Concentration of liver total cholesterol and liver TG showed a significantly decrement in all Artemisia Capillaris Thunberg EtOH ext. groups than that of control group. 3. The Artemisia Capillaris Thunberg EtOH ext. groups showed lower values in concentration of plasma TBARS and liver TBARS than that of control group. The values of GSH-Px activity, SOD activity and CAT activity were increased in the Artemisia Capillaris Thunberg EtOH ext. groups. 4. The values of plasma NO, ceruloplasmin and ${\alpha}-glycoprotein$ were decreased in Artemisia Capillaris Thunberg EtOH ext. groups. Conclusions : Based on the results in this study, the Artemisia Capillaris Thunberg EtOH ext. showed a positive effect in lowering lipid, anti-oxidation and decrement of plasma inflammatory mediators.

• 농업생명과학연구
• /
• 제46권6호
• /
• pp.117-126
• /
• 2012

본 실험은 계란의 과잉생산에 따른 여러 가지의 문제점을 해결하고 사육 농가의 소득을 증대하기 위해 계란으로 피단을 제조하는 방법을 실험하였다. NaOH의 농도를 3, 5, 7%로 기준하고 NaCl의 농도를 5, 10, 15, 20%로 기준하여 침지액을 제조하여 2일 간격으로 14일간 실험하였다. 침지액의 pH는 NaOH의 농도가 높을수록, 그리고 침지기간이 경과할수록 피단제조용 침지액의 pH는 증가하였고, NaCl의 농도가 높을수록 감소하는 경향이 나타났다. 난황의 pH는 NaOH의 농도가 진할수록 증가하였으나, NaCl의 농도에 따라서는 차이가 나타나지 않았다. NaOH와 NaCl의 농도가 높을수록 난황과 난백 침투속도는 빨라지는 것으로 나타났다. NaOH의 농도가 3%일 때 14일까지도 난백의 수양화가 되지 않았으나, 5%일 때는 11~12일째에, 7%일 때는 8~10일째에 각각 수양화가 발생하였다. 수양화가 되었을 때 난백의 pH는 11.8~12.0으로 조사되었다. NaOH의 농도가 3%일때는 12~14일 정도, 5%일 때는 10일 정도, 7%일 때는 6~7일 정도 침지 후 열처리를 하면 피단이 완성되었다. NaOH의 농도가 높을수록 침지기간 및 제조기간은 단축하였으나, 피단 난백의 수양화가 빠르게 진행되는 것이 큰 단점으로 나타났다. 따라서 NaOH가 3~5%정도가 알맞다고 생각되며, NaCl의 농도는 침지기간에는 무관하나 염도에 영향을 미치므로 5~10%정도 범위에서 조절하는 것이 적당하고 15~20%일 경우에는 염도가 높아 기호도가 떨어졌다.

• 한방재활의학과학회지
• /
• 제21권2호
• /
• pp.49-62
• /
• 2011

Objectives : This study was designed to examine the effects of Polygonatum odoratum EtOH ext. on lowering lipid and anti-oxidation using hyperlipidemic rat. Methods : Male rats weighting $195.21{\pm}4.93g$ were divided into 4 groups and fed high fat diet for 8 weeks. Each of 7 rats was divided into a control and sample group. We fed a control group of rats a basal diet and administered normal saline(100 mg/kg, 1 time/1 day) for 4 weeks. And we fed each experimental group of rats basal diet and administered an extract of Polygonatum odoratum(100 mg/kg, 200 mg/kg, 300 mg/kg, 1 time/1 day) for 4 weeks. At the end of the experiment, the rats were sacrificed to determine their chemical composition. We measured lipid of plasma and liver, concentration of anti-oxidative activity and tumor necrosis factor-$\alpha$($TNF-{\alpha}$). Results : 1. Concentration of plasma free fatty acid, low density lipoprotein-cholesterol showed a significant decrement in the 200 mg/kg and 300 mg/kg Polygonatum odoratum EtOH ext. groups than that of control group. Concentration of plasma total cholesterol, triglyceride showed a significant decrement in all Polygonatum odoratum EtOH ext. groups than that of control group. However, concentration of plasma high density lipoprotein-cholesterol was not significantly different in all the treatment groups. 2. Concentration of liver total cholesterol showed a significant decrement in the 200 mg/kg and 300 mg/kg Polygonatum odoratum EtOH ext. groups than that of control group. Concentration of liver triglyceride(TG) showed a significant decrement in all Polygonatum odoratum EtOH ext. groups than that of control group. 3. Concentration of plasma thiobarbituric acid reactive substance, and liver thiobarbituric acid reactive substance showed a significant decrement in the 200 mg/kg and 300 mg/kg Polygonatum odoratum EtOH ext. groups than that of control group. 4. The values of glutathione peroxidase activity showed a significant increment in all Polygonatum odoratum EtOH ext. groups than that of control group. The values of superoxide dismutase activity and catalase activity showed a significant increment in the 200 mg/kg and 300 mg/kg Polygonatum odoratum EtOH ext. groups than that of control group. 5. The values of plasma aspartate aminotransferase and alanine aminotransferase activities were not significantly different in all treatment groups. 6. Concentration of liver $TNF-{\alpha}$ showed a significant decrement in the 200 mg/kg and 300 mg/kg Polygonatum odoratum EtOH ext. groups than that of control group. Conclusions : Based on the results in this study, the Polygonatum odoratum EtOH ext. showed a positive effect in lowering lipid and anti-oxidation.

• 펄프종이기술
• /
• 제47권3호
• /
• pp.3-10
• /
• 2015

In this study, we evaluated properties of pulp treated with swelling agent and swelling concentration. We used swelling agent, such as NaOH, DMSO, urea. One of them, pulps treated with NaOH from 0 to 5% measured WRV, beating efficiency, crystallinity and aspect ratio. We identified that NaOH when freeness reaches 100mL CSF was the shortest, on the other hand, WRV didn't change. Because NaOH is good beating efficiency, when pulp treated with various concentration of NaOH from 0 to 5%, pulp treated 1% NaOH was best beating efficiency. However, WRV, crystalline structure and crystallinity didn't change. The more NaOH concentration increased, the more aspect ratio increased, but when NaOH concentration exceeds 3%, aspect ratio decreased. As a result, pulp treated with 1% NaOH was the greatest beating efficiency and WRV, chemical structure didn't change.

• 한국표면공학회지
• /
• 제29권2호
• /
• pp.132-139
• /
• 1996

Experiments on the automatic control of NaOH concentration and on the spraying condition of NaOH solution in the alkaline degreasing process of a continuous hot-dip galvanizing line have been carried out in order to improve degreasing performance of a galvanizing sheet steel using laboratory degreasing and galvanizing simulators. The concentration of NaOH for the good degreasing has been determined to be 6.0% and more and this concentration has been able to be automatically well controlled within $\pm$0.1% by employing a solution electrical conductivity meter under a flow injection analysis condition rather than by employing a sodium ion selective electrode in the degreasing simulator. Frequent blocking of the spraying nozzles of the solution has been reduced considerably by the set-up and periodical operation of an automatic valve system in the nozzle system. By applying this automatic valve system and by automatic controlling the NaOH concentration and other ordinary variables in the degreasing process, the degreasing performance has been increased from the conventional 76% to the new 85%.