석영과 장석의 Zeta 전위에 있어서 금속이온의 영향

오재현,박광원,이원해,원덕환 대한금속재료학회(대한금속학회) 1974 대한금속·재료학회지 Vol.12 No.4

石英과 長石의 活性化에 關한 資料를 얻기 爲해서 水溶液中 Mg^(++), Cu^(++), Zn^(++)과 Al^(+++)를 添加하여 鑛粒의 Zeta 電位를 測定하였다. 그리고 이들 鑛粒의 界面電氣現象과 金屬이온들의 加水分解特性을 서로 關聯시켜 比較 檢討하여 다음과 같은 結論을 얻었다. 1. 水溶液中에 金屬이온이 存在할 때 長石의 界面電氣現象은 石英과 같다. 2. 金屬이온種의 吸着으로 因해 石英과 長石의 界面은 陽(+)으로 荷電된다. 그리고 陽으로 荷電되는 pH 範圍는 金屬이온의 種類에 따라 다르다. 3. 水溶液中에 金屬이온들이 存在하면 鑛粒의 zpc(Zero point of charge)는 두 곳의 pH에서 나타난다. 두개의 zpc 중 하나의 zpc가 나타나는 pH는 M^(II)OH^+, M^(III)(OH)^+_2 및 M^(III)(OH)^(++) 이온種의 最高濃度가 나타나는 pH와 거의 一致한다. 마그네슘 이온의 경우에는 pH 10.1에서 단하나의 zpc가 나타난다. 4. Mg(II), Cu(II), Zn(II) 및 Al(III) 이온들의 加水分解特性과 zeta 電位를 關聯시켜 볼 때 Mg^(++), Cu^(++), Zn^(++) 및 Al^(+++)은 鑛粒表面에 對해 吸着力이 弱하고, 한편 M^(II)(OH)^+, M^(III)(OH)^+_2 및 M^(III)(OH)^(++) 이온種은 吸着力이 强함을 알 수 있다. To obtain a better understanding of quartz and orthoclase activation, zeta potentials of the minerals were studied in the presence of metallic ions such as Mg^(++), Cu^(++), Zn^(++) and Al^(+++). A microelectrophoresis technique has been used to measure the zeta potential, and the results have been correlated with the hydrolysis of the metallic ions in the solution. The experimental results have led to the following conclusions. 1. Zeta potentials of orthoclase in the presence of the metallic ions show a similar behavior to those of quartz. 2. Adsorption of the metallic ions renders the zeta potential of quartz and orthoclase positive. The pH range of positive zeta potential varies with the kind of cation. 3. Zero point of charge(ZPC) of the mineral surface in the presence of metallic ions appears at two different pH of solution. One of two pH of ZPC is consistent with the pH at which M^(II)(OH)^+ and M^(III)(OH)^+_2 or M^(III)(OH)^(++) species are predominant. 4. Comparison of the zeta potential data with the hydrolysis for Mg(II), Cu(II), Zn(II) and Al(III) species suggests that Mg^(++), Cu^(++), Zn^(++) and Al^(+++) are only weakly adsorbed at the mineral surface and that M^(II)(OH)^+ and M^(III)(OH)^+_2 or M^(III)(OH)^(++) are the main metallic ionic species adsorbed.

接觸酸化法을 利用한 LAS 除去效率에 關한 硏究

오종민,구태회,진현오,윤동선,박재영 경희대학교 환경연구소 1997 環境硏究 論文集 Vol.7 No.-

This study was performed to know LAS concentration in the small urban stream and estimate the LAS removal efficiency when apply to natural purification method with variable media. When we used gravel and concrete as media, the average LAS concentration of influent was 819.7㎍/ℓ (112.0 ∼ 1671.0 ㎍/ℓ). The average LAS concentration of effluent gravel media reactor was 58.5 ㎍/ℓ (0 ∼ 158.4 ㎍/ℓ) and average removal efficiency was 93.8%. The average LAS concentration of effluent concrete media reactor was 33.1 ㎍/ℓ (0 ∼ 136.8 ㎍/ℓ) and average removal efficiency was 96.1%. And when we used tire and scrubber, the average LAS concentration of influent was 693.7 ㎍/ℓ (241.5 ∼ 1330.3 ㎍/ℓ). The average LAS concentration of effluent tire media reactor was 88.4 ㎍/ℓ (47.8 ∼ 131.8 ㎍/ℓ) and average removal efficiency was 83.9%. The average LAS concentration of effluent scrubber media reactor was 26.1 ㎍/ℓ(0 ∼ 58.9 ㎍/ℓ) and average removal efficiency was 95.3%.

폐렴구균의 용혈능 변화와 pneumolysin 유전자의 변이 양상

오원섭,장현하,정숙인,김연숙,이혁,김신우,김성민,백경란,이남용,송재훈 대한화학요법학회 2002 대한화학요법학회지 Vol.20 No.3

목적 : 폐렴구균은 인체에서 폐렴, 수막염 및 패혈증 등을 일으키는 중요한 병원균으로 현재 전 세계적으로 항균제 내성이 큰 문제가 되고 있다. 하지만 폐렴구균의 항균제 내성에 따라 병독성이 어떻게 변화하는지에 대해서는 구체적으로 알려져 있지 않다. 이에 기능적 및 구조적 분석을 통하여 폐렴구균의 주요 병독성 인자인 pneumolysin의 병인론적 역할을 규명하고자 하였다. 방법 : 임상 검체에서 분리된 페니실링 감수성 균주 20주와 내성 균주 20주를 대상으로 하였다. Pneumolysin의 세포 독성의 변화를 관찰하기 위하여 각각의 균주들의 용혈능을 측정하였고, pneumolysin 유전자를 중합효소 연쇄반응으로 증폭한 후 증폭 산물의 유전자 구조를 분석하였다. 결과 : 페니실린 감수성 균주와 내성 균주간의 용혈능은 유의한 차이를 보이지 않았으나, 일부 용혈능이 매우 낮은 균주에서 Lys152→Thr, Thr-172→Ile, Lys-224→Arg와 같은 변이가 관찰되었다. 결론: pneumolysin의 세포 독성의 변화는 항균제 내성 정도와는 무관하였으나, 일부 용혈능이 저하된 균주에서 발견된 pneumolysin 유전자의 변이가 pneumolysin의 세포 독성에 영향을 주는 것으로 보인다. Background : Pnumolysin (Ply) is one of the most important virulence factors of Streptococcus pneumoniae. To investigate the functional and structural variation of Ply, hemolytic activity (HA) and gene sequences of pneumolvsin were determined. Methods : A total of 40 invasive pneumococcal isolated (20 penicillin-susceptible & 20-resistant strains) were analyzed. HA of each isolate was measured in crude extracts (1×10^8 CFU/mL) hourly from the time of inoculation to 9h. Crude extracts (50㎕) and DTT buffer (100㎕) were serially diluted in 96-well plate and mixed with 1% sheep blood (50㎕). HA was represented as the reciprocal of the greatest dilution, which resulted in the complete lysis. Two sets of oligonucleotide primers were used to amplify a 1,474-bp fragment containing the coding region and a 578-bp fragment of upstream region of ply gene, respectively. Amplified products were directly sequenced. Results : HA showed a wide variation from 0 to 87,480 regardiess of penicillin MICs, serotypes or specimen sources. Two bacteremic strains showed completely no hemolytic activity. No significant differences in HA between penicillin-susceptible (Mean± SE : 15,468± 4,693) and penicillin-resistant strains (21,384± 4,087) were found (p > 0.05).Sequencing of the coding region showed unique alterations in amino acids in strains with markedly reduced hemolytic activity (≤ 40): Thr-172-Ile and Lys-224-Arg. However, upstream region of ply gene was highly conserved. Conclusions : Ply activity was not related with antibiotic resistance. Absence of HA in some strains was associated with unique alterations in amino acid sequences in ply gene. Relationnship between genomic alteration and functional changes in pneumolysin should be further investigated.

대구지역 거주자의 식생활 습관과 위장질환과의 관계

오미정,김수월,양희면,현재식,허천식,이명화 한국건강관리협회 2000 건협 Report Vol.3 No.-

營業停止 處分을 받은 衛生業主들의 意識行態

오서경,박재용,한창현,차병준 경산대학교 보건복지연구소 2000 保健福祉硏究 Vol.5 No.-

A survey was conducted to 252 owners of restaurants and taverns who, during the period of from Jan, 1 1998 to Sept.15 1998, were ordered by the authorities concerned to suspend their businesses due to the violations of relevant laws an regulations. Out of 252 questioned 195(77.4%) were those who completed the required orientation course for owners of the above businesses. It is found that the rate of completion of the course are higher among those who had been running the business for a longer period of time, and alwo among those who had bigger facilities. Asked how they found the current laws and regulations relevant to their businesses, 68.7% of the surveyed replied that the existing laws and regulations should be abided by while 26.6% wanted flexible application of the laws and regulations. Those who demanded complete revision of the laws and regulations were only 4.8% of the questioned. Restaurant owners marked the high rate of 71.3% in the support of the existing laws and regulations, while tavern owners' supporting figure was around 60%. Analyzing the owners of restaurants and taverns who were ordered to suspend their businesses due to their violations of the relevant laws and regulations, it was found that female owners, owners with higher ages, less educated owners and owners of taverns were more likely to violate regulations than the others. And the older establishments, the smaller in size of establishment, and establishments with lesser number of employees were also found to be more likely to make violations. The reasons for the suspension of businesses were as follows in its order of percentage; violation of business hours(37.7%), selling of alcohol to minors(13.9%), abnormal business activities(12.7%), indecent entertainment(10.3%), employment of under-aged waitresses(8.3%). Public prosecutor's office, police, municipal office and district office of a city are empowered to enforce the relevant laws and regulations on restaurants and taverns and to suspend businesses, 43.3% of all the suspension of businesses were made by district offices and 42.5% of them by police, 48.8% of the respondents showed their preference for district office to other law enforcing agencies. Next came municipal office with 29.4% followed by public prosecutor's office(25.0%) and police(21.8%). 77.0% of the questioned answered that they would rather have paid fine than having been suspended of businesses. And most of the owner of the suspended businesses replied that the duration of suspension of businesses must be shortened. Most of the owners of restaurants and taverns who had experienced suspension of businesses(94.0%) replied that they would close their businesses for good if their businesses were suspended again. Asked to make any proposal or suggestion, 67.1% of the surveyed wanted that when any violation were found by the law-enforcing agencies the owners of the businesses were given a chance to correct it before being booked for violation.

광주광역시 도시공간구조 변화에 관한 연구

오재화,김우혁,김현웅 朝鮮大學校 建設技術硏究所 2002 建設技術硏究 Vol.22 No.1

The purpose of this thesis is to inspect the step of spatial structure varied with the urban growth in place of Kwang-ju, to analyze the developing step of urban growth on the basis of the variety of shape-index and function-index on urban from 1930 to 1992 each year, to predict the variety direction of urban spatial structure for the concentrating and efficient urban function and to grope for the prospects of urban : what is the municipal concept in the land use, the variety of population, the change of traffic system, the change of urban planning zone, the change of executive zone, the transition of spatial structure on the basis of urban growth in Kwangiu. Considering the advent of subway in 1990, Pyoung-Dong industrial block, to work out these factors, the urban pattern in Kwangiu would be developed and established in aspect of long-range planning. The size of population, the changing pattern of land use planning and zonning are compared and analyzed to justify the relation with the urban comprehensive planning circulation planning.

矯正用線材의 機械的性質에 미치는 熱處理의 影響

吳容和,成在鉉 慶北大學校 齒科大學 1985 慶北齒大論文集 Vol.2 No.1

The objective of this study was to evaluate the effect of heat treatment on mechanical properties in.016" Green Elgiloy wires. Ultimate tensile strength, yield strength and elongation were measured with Instron type tension testing machine. The results were as follows: Ultimate tensile strength and yield strength were progressively increased by heat treatment, but elongation was decreased. Increased degree of strength by heat treatment was more effective by temperature than time. Ultimate tensile strength showed the highest value(231.6Kg/㎟) after heat treatment for 3 and 6 minutes at 550℃, and progressively decreased after heat treatment at 600℃. Yield strength showed the highest value (120.4Kg/㎟) after heat treatment for 6 minutes and 9 minutes at 550℃. Elongation showed the lowest value(7.4%) after heat treatment for 12 minutes at 500℃ and 550℃. The optimal temperature and time of heat treatment were 550℃ and 6±3 minutes.

모 제약회사 근로자들의 직업성 천식 유병률과 약제 분말 노출수준

오성수,최용휴,김은아,이영목,장재길,유장진,박승현,김태균,정수영,김규상,강성규 大韓産業醫學會 2006 대한직업환경의학회지 Vol.18 No.2

목적: 제약회사에서 직업상 천식의 유병 규모를 파악하고 작업공정에 대한 작업환경 측정을 통해 제약회사의 약제 분말에 대한 노출수준을 평가하고자 하였다. 방법: 제약회사에서 약제 분말에 노출되는 근로자를 대상으로 천식을 선별하기 위하여 설문조사 및 진찰, 혈액검사, 폐기능 검사 그리고 피부단자시험을 실시하였고, 각 부서별 공정에 따라서 총분진과 항생제 또는 효소제 분말에 대한 작업환경 측정을 실시하였다. 직업상 천식이 의심되는 근로자에 대하여 기관지과민성에 대한 검사(메타콜린을 이용한 비특이 기관지유발시험)와 약제 분말 기관지유발시험을 실시하여 확진하였다. 결과: 설문조사 및 진찰에서 작업 관련 천식 증상이 있는 근로자는 11명(34.4%)이었고, 약제 분말을 이용한 피부단자시험에서 1+ 이상 반응을 보인 근로자 10명(31.2%)이었다. 비특이 기관지유발시험 결과 8명(25.0%)이 양성(PC20 ≤16 mg/ml)이었다. 약제 분말 기관지유발시험을 통해 직업상 천식으로 확진된 근로자는 5명(15.6%)이었다. 작업환경 측정에서 원료를 충진하거나 투입하는 작업 그리고 정립작업에서 약제 분말에 대한 노출이 많았다. 결론: 제약회사에서 직업상 천식은 주로 제조공정 중 약제 분말에 노출된 근로자에서 발생하여, 증상 및 직업성 천식의 유병률이 높았다. 따라서 원료를 충진 또는 투입하는 작업과 정립작업 등 제조과적에서 약제 분말 노출을 줄이기 위한 세심한 주의가 필요하여, 약제 분말을 취급하는 근로자에 대해서는 천식 증상 조사뿐 아니라 정기적으로 피부단자시험, 비특이 기관지유발시험 등을 실시하여야 할 것이다. Objectives: After the investigation of one worker with occupational asthma, we surveyed the preva- lence of occupational asthma and the exposure level of pharmaceutical dust of 32 workers in a pharmaceutical company. Methods: Thirty-two of the 90 employees participated in the survey which consisted of questionnaire, blood sampling, spirometry and skin prick tests with 8 common allergens as well as 9 antibiotics and 2 enzymes. Various indices of the working environment were also measured. Subjects who had a symptom suggestive of work-related asthma or positive skin prick test were further investigated by PC20 methacholine. Nine subjects who had a PC20 result of 16 mg/ml or less (n=7) or had work-related symptoms and positive skin prick test (n=2) were referred to undergo a specific bronchial provocation test to phar- maceutical dust in an academic allergic disease center. Results: Eleven of 32 workers (34.4%) had a work-related symptom suggestive of occupational asthma. Ten (31.2%) showed positive skin prick test. 8 (25.0%) had a PC20 result of 16 mg/ml or less (indicative of significant bronchial hyperresponsiveness), and 5 (15.6%) had a positive result on the specific bronchial provocation test. Exposure levels of stuffing, input of raw materials and screening process were relatively high. Conclusions: This survey showed that pharmaceutical workers have an increased risk of occupational asthma. Although pharmaceutical factories maintain a relatively good working environment, careful control of respiratory tract exposures, especially during stuffing, input or raw materials and screening process, is important to prevent occupational asthma. Pharmaceutical workers need to undergo regular skin prick and methacholine bronchial provocation tests, as well as asthmatic symptom survey, to ensure the early detection and prevention of occupational asthma.

Ten-Two mechanics에 의한 고정원 준비시 하악구치와 전치 주위조직의 응력 분포에 관한 광탄성법적 분석

오준기,성재현 慶北大學校 齒科大學 1992 慶北齒大論文集 Vol.9 No.1

하악의 고정원 형성시 Ten-Two mechanics을 사용할때 하악구치와 하악전치의 치근 주위조직에 미치는 영향을 평가하기 위하여, 제1소구치 발치 증례에서 평준화와 전치부의 견인이 끝난 에폭시모형을 제작하였다. 에폭시모형상상에서 Ten-Two mechanics와 high pull J-hook headgear를 사용하여 준비고정한 것과 Ⅲ급 고무로 준비고정 하였을 때, 하악구치와 전치 주위조직에 나타난 응력 분포 상태를 광탄성법으로 비교 분석하여 다음과 같은 결과를 얻었다. · Ⅲ급 고무를 사용시, 하악 구치부에 후방경사이동 양상이 전반적으로 나타났으며, 전치부에는 압입의 양상이 상당히 나타났다. · 10-2-7 mechanics와 high pull J-hook headger를 사용시, 하악 제2대구치에 후방경사이동 양상이 나타났고, 전치부에는 거의 압입의 양상이 나타나지 않았다. · 10-2-6 mechanics와 high pull J-hook headger를 사용시, 하악 제1대구치에 후방경사이동 양상이 나타났고, 전치부에는 거의 압입의 양상이 나타나지 않았다. · 10-2-5 mechanics와 high pull J-hook headger를 사용시, 하악 제2소구치에 후방경사이동 양상이 나타났고, 전치부에는 거의 압입의 양상이 나타나지 않았다. This study was performed to analyze the effects of Ten-Two mechanics applied to prepare mandibular anchorage on the surrounding tissues of the mandibular molars and incisors. The photoelastic model was constructed as the premolar extraction case which leveling and retraction of anteriors were finished. In this epoxy resin model, mandibular anchorage was prepared by two methods, that was Ten-Two mechanics with high pull J-hook headgear and Class Ⅲ elastics. The obtained stress distribution on the surrounding tissues of the roots was analyzed by photoealstic method. The results were as follows: 1. When Class Ⅲ elastics were used in preparing mandibular anchorage, distal tipping movement tendency occurred overally in the madibular molars and considerable intrusion occurred in the incisors. 2. When 10-2-7 mechanics with high pull J-hook headgear used in preparing mandibular anchorage, distal tipping movement tendency occurred in the mandibular second molar and the least intrusion occurred in the incisors. 3. When 10-2-6 mechanics with high pull J-hook headgear used in preparing mandibular anchorage, distal tipping movement tendency occurred in the mandibular first molar and the least intrusion occurred in the incisors. 4. When 10-2-5 mechanics with high pull J-hook headgear used in preparing mandibular anchorage, distal tipping movement tendency occurred in the mandibular second premolar and the least intrusion occurred in the incisors.

라즈베리파이와 아두이노를 활용한 캠핑 멀티 박스

김종현,오제용,함승수,이재건,이순흠 순천향대학교 부설 산업기술연구소 2021 순천향 산업기술연구소논문집 Vol.27 No.2

There is a rising hobby in the COVID-19 pandemic era. At this point, camping accidents are also occurring a lot as more people are camping in cars and outdoors. Most of the casualties among them are carbon monoxide poisoning accidents. Therefore, to prevent carbon monoxide poisoning, we measured with an Arduino board using a "DHT22" sensor and an "MQ7" sensor to know temperature, humidity, and carbon monoxide levels, and then printed it out on LCD after storing it in Raspberry Pi database. Therefore, it is implemented through 3D printing on the appearance modeled directly to the actual user.