• Title/Summary/Keyword: pH standard test

Search Result 237, Processing Time 0.032 seconds

Development of Control Technology for Acid Mine Drainage by Coating on the Surface of Pyrite using Chemicals (산성광산배수의 발생저감을 위한 황철석 표면의 피막형성 기술개발)

  • Ji, Min-Kyu;Yoon, Hyun-Sik;Ji, Eung-Do;Lee, Woo-Ram;Park, Young-Tae;Yang, Jung-Seok;Jeon, Byong-Hun;Shim, Yon-Sik;Kang, Man-Hee;Choi, Jae-Young
    • Journal of Soil and Groundwater Environment
    • /
    • v.15 no.4
    • /
    • pp.46-52
    • /
    • 2010
  • Acid mine drainage occurs when sulfide minerals are exposed to an oxidizing environment. The objective of this study was to inhibit the oxidation of pyrite by applying various coating agent such as $KH_2PO_4$, MgO and $KMnO_4$ over its surface as an oxidation inhibitors. Experiments were conducted for 8 days to test the feasibility of oxidation inhibitors. The optimal condition of coating agent for standard pyrite and IK mine was the combination of 0.01M $KH_2PO_4$, 0.01M NaOAc and 0.01M NaClO. Otherwise, for YD mine the combination of 0.01M $KMnO_4$, 0.01M NaOAc and 0.01M NaClO. The $SO_4^{2-}$ reduction efficiency of pyrite, IK and YD mine samples was 70, 92 and 84%, respectively. For 8 days, no significant increase of $SO_4^{2-}$ from pyrite sample coated with inhibitor was observed. The pH of solution remains in between 4 to 6 for the reaction conditions.

A Development on Assessment Method of PVC Gloves Used in Pest Control Program (해충제어프로그램에서 사용되는 PVC장갑의 평가방법 개발)

  • Lee, Su-Gil;Lee, Nae-Woo
    • Journal of the Korean Society of Safety
    • /
    • v.21 no.3 s.75
    • /
    • pp.53-58
    • /
    • 2006
  • Following a Mediterranean fruit fly outbreak in South Australia, a bait spray program involving the pesticides like malathion(MAL) was carried out. During the application, dermal exposure was considered for the pest controllers wearing PVC gloves. However there is a lack of information about PVC glove performance like break through times and permeation rates with MAL, therefore, a new analytical method for HPLC-UV was developed. A standard permeation test cell was used in this study. From the results of this study, more than 96% solubility of MAL was provided at 30% isopropyl alcohol in distilled water as a collecting media. However, there was significant decomposition of MAL when the solutions were kept at over $50^{\circ}C$ for 2-3 hours. As a mobile phase, 50% acetonitrile water solution (pH 6.0) gave the greater sensitivity compared with other compositions of acetonitrile solution. The arm section of the gloves had shorter breakthrough times and higher permeation rates compared with the palm. There was no malathion solution breakthrough up to 24 hours using the 1% MAL working strength solution. When the temperature was changed from $22{\pm}1^{\circ}C\;to\;37{\pm}1^{\circ}C$, the breakthrough times were decreased by 14.5% on palm and 37.5% on arm, and permeation rates were increased significantly. The findings of this study indicate that further investigations on used gloves, periods of use and varying working conditions like tasks and seasons should be carried out to assess potential worst case scenarios.

Shear Bond Strength of Porcelain Repair Systems (도재 수리 시스템의 전단결합강도에 관한 연구)

  • Woo, Soo;Shin, Soo-Youn;Cho, In-Ho
    • Journal of Dental Rehabilitation and Applied Science
    • /
    • v.22 no.3
    • /
    • pp.211-220
    • /
    • 2006
  • Need of porcelain-repair system is largely demanding as dental porcelain restorations are increased in clinical dentistry. This study investigated shear bond strength of commercial porcelain-repair systems on dental porcelain and their reliability. Experimental groups were as follows; Group A Super Bond C&B, Group B Porcelain repair kit, Group C Ceramic repair, and Group D Spectrum system as a control. Porcelain disks were fired and embedded in epoxy resin. Porcelain surface were ground using 220 grit SiC disk, then cleaned in ultrasonic bath. Then porcelain specimens were treated with each repair system. A clear polystyrene cylinder 3.5 mm in internal diameter was filled with composite resin. Then the resin cylinder was polymerized with a visible light curing unit. Thirty one specimens at each group were prepared and stored at $37^{\circ}C$ distilled water for 48 h. Specimens were tested in an Instron testing machine according to ISO TR 11405. Mean shear bond strength and standard deviation of each group was $15.7{\pm}4.1MPa$ (Group A), $12.8{\pm}4.9MPa$ (Group B), $7.2{\pm}3.0MPa$ (Group C) and $9.6{\pm}2.2MPa$ (Group D). ANOVA and Tukey HSD post-hoc test showed that there were significant differences between groups (p<0.05). Data of bond strength were analyzed with two-parameter Weibull distribution. Confidence interval of Weibull modulus (m-parameter) at 95% of Group A (3.5-6.3) and Group D (3.6-6.0) were significantly higher than Group B (2.2-3.7) and Group C (2.0-3.4). There was little correlation between mean shear bond strength and Weibull modulus. Results indicated that acid-etching of porcelain surface increased porcelain-resin shear bonding strength.

Effect of Balance Training on Ankle Muscle Activity and Static Balance in Stroke Patients (균형훈련이 뇌졸중환자의 발목 근육 활성도와 정적균형에 미치는 영향)

  • Lee, Young-Min;Kim, Sang-Chul;Yoon, Sung-Kyeung
    • PNF and Movement
    • /
    • v.12 no.4
    • /
    • pp.209-215
    • /
    • 2014
  • Purpose: This study aims to understand the effect of balance training on ankle muscle activity and static balance in stroke patients. Methods: The subjects were composed of 12 patients who were admitted with chronic stroke in H, K, and R hospitals located in Gangwon-do from August to October 2014. This study conducted balance training on the subjects for 20 min a session, twice a day, five times a week for six weeks. This study measured the surface electromyogram (EMG) of the paretic side's tibialis anterior and medial gastrocnemius for muscle activity. Static balance was measured as a TETRAX stability index. The measurements were conducted before the experiment and six weeks after. The result was statistically analyzed using paired t-test at the significance level of 0.05. Result: Muscle activity of the paretic side's tibialis anterior and medial gastrocnemius did not show a significant difference in the comparison between pre- and post-balancing training. However, the stability index showed a significant difference (p<0.05) between standing with eyes open (NO) and standing on a sponge with eyes open (PO). Conclusion: Although balance training did not affect the muscle activity of chronic stroke patients, it had an effective influence on the stability index. That is, balance training was effective at the functional level, but it did not change the structure level in terms of the ICF evaluation standard. Balance training becomes more effective when it is applied in relation to task.

Characterization of canine coronaviruses isolated from the dogs with diarrhea in Korea (설사증 이환견(犬)으로 부터 분리(分離)한 canine coronavirus의 성상(性狀)에 관한 연구(硏究))

  • Lee, Byung-hyung;Jun, Moo-hyung;Park, Jong-hyeon;Hwang, Eui-kyung;Huh, Won
    • Korean Journal of Veterinary Research
    • /
    • v.34 no.3
    • /
    • pp.517-527
    • /
    • 1994
  • An attempt was made to isolate a causative viral agents from the fecal specimens of the diseased dogs with the gastroenteritis symptoms. Two coronavirus-like agents were isolated by serial dilution end point method and plaque assay. The isolates were characterized in terms of cytopathology, antigenicity, replication, physicochemical and morphological properties. The results obtained through the experiment were as follows; 1. Among 7 fecal specimens collected from the dogs with enteric disease, 2(28.6%)coronavirus-like agents showing typical cytopathic effects of canine coronavirus were isolated, and designated as CCV D1 and CCV D2, respectively. 2. By the cross-neutralization test and indirect immunofluoresence antibody test, the isolates were antigenically indentified as the standard CCV. The viruses were replicated only in the cytoplasm of A-72 cells. 3. The isolates showed no haemagglutinating activity against the erythrocytes from 11 kinds of animals. 4. The electron microscopic observation for the isolates showed spherical and pleomorphic features, covered with club-shaped projections on the surface. The size of particles was ranged from 70 to 150nm. 5. In one-step growth curve for the isolates in A-72 cells, maximum titers of intracellular vius was $10^{4.6}$ $TCID_{50}/0.1ml$ at 46 hrs postinoculation(pi) of CCV Dl and $10^{4.4}$ $TCID_{50}/0.1ml$ at 34 hrs pi of CCV D2. The maximum titers of extracellular virus was $10^{5.5}$ $TCID_{50}/0.1ml$ at 58 hrs pi of CCV D1 and $10^{5.8}$ $TCID_{50}/0.1ml$ at 46 hrs pi of CCV D2. 6. In physicochemical property test, the isolates were very sensitive to choroform and were found to be RNA virus. The viruses was stable at pH 3.0 for 1 hr and at $22{^{\circ}C}$ for 5 hrs. However, infectivity titers reduced remarkably by treatment with $56{^{\circ}C}$ for 10min.

  • PDF

The Effect of Moosim-Gi-Gong Doinbeop on Treatment of Low Back Pain (무심기공 도인법이 요통치료에 미치는 효과)

  • Jang, Sang Chul;Chong, Myong Soo;Pi, Chien Mei;Ahn, Hun Mo;Lee, Jae Heung;Roh, Ju Hee;Bae, Jae Ryong
    • Journal of Korean Medical Ki-Gong Academy
    • /
    • v.18 no.1
    • /
    • pp.1-26
    • /
    • 2018
  • The objective of this study is to verify the effects of Moosim-Gi-Gong Doinbeop on low back pain targeting low back pain patients hospitalized in Korean medicine hospitals. For the study, 44 adult female and male patients hospitalized with low back pain at M Korean Medicine Hospital and H Korean Medicine Hospital located in Gimpo, Gyeonggi Province were recruited. The subjects had a temperature difference between left and right 湧泉(KI1) of over 0.5℃ through infrared thermographic imaging, and 23 of them were classified in the control group for retrospective analysis based on the test records. Infrared thermographic imaging, X-ray pelvic AP view - standing position, a sit-and-reach test and a VAS survey were employed for detection, and IBM SPSS Statistics 24 for the statistical process. The results were rounded down to three decimal places as in an average±standard deviation, and the significance level was 0.05 to be evaluated significant if p<0.05. The result of the study is as follows: 1. In the comparison between before and after conducting Moosim-Gi-Gong Doinbeop, the meaningful difference was shown in the experimental group in all indicators. But Indicators except for the temperature difference between right and left 湧泉(KI1)(difference between before and after) and In displaced pelvic correction indicators on the X-ray showed a significant difference in the control group. 2. As for the variation widths of the experimental group and the control group, the former showed significant temperature differences between 印堂(EX-HN3) and 關元(CV4) and right and left 湧泉(KI1); difference variations of anteflexion; and changes in PI and In displacement on the X-ray. 3. As for changes in the experimental group according to demographic characteristics, gender, age and degree of obesity did not show significant differences in all indicators. However, those who experienced back pain for more than six months in the experimental group showed the biggest body temperature differences between 印堂(EX-HN3) and 關元(CV4), while other indicators had no significant difference. As a result, patients who received Korean medicine treatment showed relieved back pain and improvement in pelvic correction and sports activity; however, those who got Moosim-Gi-Gong Doinbeop together showed more clearer improvement effects in pelvic correction and sports activity.

Retention of CAD/CAM Metal Copings Cemented on Short Titanium Abutments with Different Cements (짧은 티타늄 지대주에 합착된 CAD/CAM 금속 코핑의 시멘트 종류에 따른 유지력 비교)

  • Kim, Hyo-Jung;Song, Eun-Young;Yoon, Ji-Young;Lee, Si-Ho;Lee, Yong-Keun;Oh, Nam-Sik
    • Journal of Dental Rehabilitation and Applied Science
    • /
    • v.28 no.2
    • /
    • pp.119-126
    • /
    • 2012
  • State of problem: Cement-retained implant-supported prostheses are routinely used in dentistry. The use of high strength cements has become more popular with the increasing confidence in the stability of the implant-abutment screw connection and the high survival rates of osseointegrated implants. No clinical data on retention of metal copings using CAD/CAM. To evaluate retention of metal copings using CAD/CAM system bonded to short titanium abutment with four different cements and compare retentive strength of metal copings with sandblasting or without sandblasting before cementation. Forty titanium abutment blocks were fabricated and divided into 4 groups of 10 samples each. Forty metal copings with occlusal hole to allow for retention testing were fabricated using CAD/CAM technology. The four cements were Fujicem(Fuji, Japan), Maxcem Elite(Kerr, USA), Panavia F2.0(Kurarary, Japan) and Superbond C&B(Sunmedical, Japan). The copings were cemented on the titanium abutment according to manufacture's recommendation. All samples were stored for 24h at 37oC in 100% humidity and tested for retention using universal testing machine(Instron) at a crosshead speed of 1.0mm/min. Force at retentive failure was recorded in Newton. The mode of failure was also recorded. Means and standard deviations of loads at failure were analyzed using ANOVA and Paired t-test. Statistical significance was set at P<0.05. Panavia F2.0 provided significantly higher retentive strength than Fujicem, Maxcem Elite(P<0.05). Sandblasting significantly increased bond strength(P<0.05). The mode of failure was cement remaining principally on metal copings. Within the limitation of this study, Panavia F2.0 showed significantly stronger retentive strength than Fujicem, Maxcem Elite(p<0.05). The Ranking order of the cements to retain the copings was Panavia F2.0, Fujicem = Maxcem Elite. Sandblasting significantly increased bond strength(P<0.05). The retentive strength of metal copings on implant abutment were influenced by surface roughness and type of cements.

Effects of Diffusibility of Bubbling Tablet Herbicide Formulations for Paddy Rice (수도용 발포성정제 제초제의 확산성에 미치는 영향)

  • Kim, Man-Ho;Ryang, Kwang-Rok;Lee, Chang-Hyeuk;Shim, Jae-Weon;Kim, Kyung-Hyun;Yoon, Cheol-Su;You, Yong-Man;Pyon, Jong-Yeong
    • The Korean Journal of Pesticide Science
    • /
    • v.9 no.4
    • /
    • pp.401-410
    • /
    • 2005
  • A series of studies involving formulation processes, bubbling activity test, diffusibility test and biological efficacy test was undertaken to develop Jumbo herbicide formulations in paddy rice field. Gas evolution speed from the tablets prepared by different organic acids was in the order of oxalic acid, malonic acid, citric acid, and tartaric acid. The total volume of evolved gas from the tablet and diffusibility of the active ingredient in the submerged water were increased with increase of water temperature; the volume from 1 g of tablet at 10, 15, 25 and $30^{\circ}C$ for 5 minutes after immersion into water was 20, 25, 28, 45, 57 mL, respectively. The concentration of halosulfuron-methyl and pyriminobac-methyl in submerged water at 5, 15, 20 and $30^{\circ}C$ at the 2.4 m distance from the applied spot of the tablet was 20, 48, 85, and 97% of the concentration of treated spot, respectively. The evolved gas volume from the tablets was not affected by pH of submerged water. The concentration of halosulfuron-methyl in different sizes of submerged water within 24 hours after treatment of the tablet was maintained 0.16 ppm, which is ideal concentration at standard dosage regardless of the submerged water area. The concentration of pyriminobac-methyl was also uniformly dispersed in the water within 24 hours after applying it into the submerged water. The wind velocity of 5 m $sec^{-1}$ on concentration distribution of halosulfuron-methyl and pyriminobac-methyl in the submerged water 24 hours after treatment was not influenced; an equal concentration in the up the wind and down the wind from the applied spot was maintained. Spot treatments of one tablet formulations(5 g) including 4 times higher dosage at 4 different spots resulted in even concentration distribution of active ingredient in the water 24 hours after applying it into the submerged water.

The Study of Pain and Pain Management of Cancer Patients (악성종양 환자의 통증 및 통증관리에 관한 연구)

  • Yoon Gwi-Ok;Park Hung-Sook
    • Journal of Korean Academy of Fundamentals of Nursing
    • /
    • v.3 no.2
    • /
    • pp.299-316
    • /
    • 1996
  • This study is the descriptive survey to provide basic data for nursing intervention to pain management of cancer patients by finding more effective way to manage pain with recognize pain level and pain characteristics. To achieve the purpose of this study, the subjects of this study are 110 male or female gastro intestinal tract patients who are older than twenty, are hospitalized in Pusan University Hospital from 1995. 5. 28 to 1995. 9. 25 and have had medical treatment. The modified pain assessment of cancer patients of Cornne, H. Rosermary, M. was used as the tool of study with 16 questionaries. The pain score consists of sensory intensity score and distress score. The data was analyzed by the SPSS statistical program number, percentage, mean, standard deviation, t-test, One Way Anova and Duncan's Multiple Range Test were utilized for analysis. The results were summarized as follows : 1. In population-sociological characteristics : in the age-range of subject, the sixties are most as 32.7% and the subjects after the forties are 89.5%, in sex of subjects, male patients are 66.4% and female 33.6%, in the number of family, the subjects who has 4 or above families are 70% and the subjects who live with their spouse, sons and daughters are 54.5% 2. In the disease characteristics : stomach cancer patients were most as 39.1%. And the most of patient who had never been operated before. In time of pain, the most of subjects were intermittent. In the type of pain, the most of subjects were 'dully pain' as 31.8%. Metastatic subjects were 30.0%. In the origin of pain, nervous pressure was 50.8%. The number of complication was 46 and most of complication are obstruction as 6%. 3. In the pain level, 91subjects complained pain. And mean pain score was $287.1{\pm}116.1$ The mean pain score of female subjects was higher than that of male subjects. 4. In the pain characteristics, the pain began usually at meal time as 40.7%. The duration of pain was mostly from 1 month to 3 months as 57.1%. The appetite was mainly concerned with the pain as 31.8%. The etiology of pain was usually tumor as 69.3%. The meaning of pain was incurable disease as 14.5%, anxiety, death and suffering. 5. The 56(61%) of 91subjects were treated with Analgesic pain management. The kinds of Analgesic is usually valentac as 46.4%. The medication was usually intramuscle as 66.1% at whenever necessary, Response of Analgesic after Medication was usually 'moderate release'. The side effects of medication were nausea as 26.8%. The average amount of morphine dosage hospitalized to cancer patients with pain was 80mg in a day and metastatic cancer patients with pain was 101.9mg in a day. 6. In the relation between the disease characteristics and pain level, there is a significant statistical difference : whether subjects had been operated or not : (t=2.88, p=0.005), time of pain is(t=3.34, p=0.005), stage of metastatic(F=9.323, P=0.0002), and type of pain(F=4.013, p=0.0008). In the pain level of diagnosis, Colon cancer was $353.3{\pm}81.7$(F=2.34, p=0.049), the origin of pain, nerve pressure $316.3{\pm}98.5$(F=2.44, P=0.045), In the complication, ascites and obstruction $324.9{\pm}96.8$(T=2.60, P=0.04).

  • PDF

Contamination status of groundwater used as livestock drinking in beef and dairy cattle farms, Korea (국내 소사육농가의 자가용 가축음용수 오염실태 평가조사)

  • Jang, Yangho;Lee, Soojin;Kim, Hyobi;Lee, Jeonghak;Lee, Manho;Gil, Hyekyoung;Choe, Nonghoon
    • Korean Journal of Veterinary Research
    • /
    • v.51 no.1
    • /
    • pp.47-53
    • /
    • 2011
  • In Korea, groundwater is main water source in livestock farms. Most dairy and cattle farms have constructed their own wells for human drinking and livestock farming. However, these private residential wells have not been controlled by government and also there was scant study about livestock drinking water quality. Therefore this study was to monitor of the livestock farms' groundwater quality in Korea. Water samples were collected at 123 dairy and cattle farms and were analysed forty six substances with quality standard for drinking water approved by the Minister of Environment. Seventy eight (63.4%) of 123 samples failed to drinking water stand a test. The most frequent contaminants were nitrate-nitrogen and microbial. 22.8% (n=28) of samples showed nitrate-N concentration of higher than 10 mg/L meant that can't be used drinking water for human and the Nitrate-N concentration analysed in the range of 0.2 to 61.2 mg/L. All of 78 failed to drinking samples had microbial problems, especially 5.7% (n=7) of samples indicated water could be contaminated by feces. Other contaminants detected were zinc and evaporation residue. Especially detected zinc concentration (32 mg/L) was about ten times higher than standard of zinc (3 mg/L). Regression analysis indicated that groundwater pH did not influence to nitrate-N concentration but the hardness and chloride could affect to nitrate-N concentration in the groundwater. Most livestock farms were adjacent to crop farmland in Korea. This could cause contamination of groundwater with nitrate-N and pesticide that could accumulate livestock product. Moreover Heavy metal such as zinc and copper could be released from a corrosive plated water pipe in livestock farm. Put together, Korea livestock system is indoor, not pasture-based, hence livestock could be exposed to potential contaminated water consistently. Therefore on the basis of these data, appropriate livestock drinking water quality standards should be prepared to keep livestock healthy and their product safe. Further, livestock drinking water quality should be monitored continuously in suitable livestock drinking water standards.