• 제목/요약/키워드: initial pHs

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암 환자의 희망 측정도구 개발 (Development of the Hope Scale for Korean Cancer Patients)

  • 태영숙;최윤숙;남금희;배주영
    • 성인간호학회지
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    • 제29권2호
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    • pp.211-223
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    • 2017
  • Purpose: This study was designed to develop and test the Hope Scale for Korean cancer patients. Methods: The process for the development of the Hope Test was a selection of initial items drawn from a literature review and in-depth interviews. The selected items were assessed for content validity by experts. The Hope Scale was comprised of five factors and 30 preliminary items. The preliminary Hope Scale for Korean Cancer Patients (HS_KCP) was administered to 259 cancer patients from one university hospital and one cancer hospital in Busan. Data were analyzed using item analysis, factor analysis, Pearson correlation coefficients, and Cronbach's ${\alpha}$. Results: Eighteen items were selected for the final scale. Five factors (inner sense of control, trust and expectation for recovery of disease, interconnection, spirituality, emotional despair) evolved from the factor analysis, which explained 63.3% of the total variance. The convergent & discriminent validity was r=.83 (p<.001), r=-73 (p<.001). The internal consistency, Cronbach's ${\alpha}$ was .88 and reliability of the subscales ranged from .54 to .85. Conclusion: The Hope Scale for Korean cancer patients demonstrated acceptable validity and reliability. It can be used to assess the hope of cancer patients and is feasible within a clinical setting.

Evaluation of Electrokinetic Removal of Heavy Metals from Tailing Soils

  • Kim, Soon-Oh;Kim, Kyoung-Woong;Yun, Seong-Taek
    • 한국지하수토양환경학회:학술대회논문집
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    • 한국지하수토양환경학회 2002년도 추계학술발표회
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    • pp.40-43
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    • 2002
  • Electrokinetic remediation was studied for the removal of toxic heavy metals from tailing soils. This study emphasized the dependency of removal efficiency upon heavy metal speciation, as demonstrated by different extraction methods (sequential extraction, total digestion, and 0.1 N HC1 extraction). The tailing soils examined showed different physicochemical characteristics, in view of initial pH, particle size distribution, and major mineral constituents, and contained high concentrations of target metal contaminants in various forms. The electrokinetic removal efficiency of heavy metals was significantly influenced by their partitioning prior to treatment, and by the pHs of the tailing soils. The mobile and weakly bound fractions of heavy metals, such as exchangeable fraction, were easily removed by electrokinetic treatment (more than 90% in removal efficiency), whereas immobile and strongly bound fractions, such as organically bound and residual fractions, were not effectively removed (less than 20% in removal efficiency).

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Cobalt ferrite nanotubes and porous nanorods for dye removal

  • Girgis, E.;Adel, D.;Tharwat, C.;Attallah, O.;Rao, K.V.
    • Advances in nano research
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    • 제3권2호
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    • pp.111-121
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    • 2015
  • $CoFe_2O_4$ nanotubes and porous nanorods were prepared via a simple one-pot template-free hydrothermal method and were used as an adsorbent for the removal of dye contaminants from water. The properties of the synthesized nanotubes and porous nanorods were characterized by electron diffraction, transmission electron microscopy and x-ray powder diffraction. The Adsorption characteristics of the $CoFe_2O_4$ were examined using polar red dye and the factors affecting adsorption, such as, initial dye concentration, pH and contact time were evaluated. The overall trend followed an increase of the sorption capacity reaching a maximum of 95% dye removal at low pHs of 2-4. An enhancement in the removal efficiency was also noticed upon increasing the contact time between dye molecules and $CoFe_2O_4$ nanoparticles. The final results indicated that the $CoFe_2O_4$ nanotubes and porous nanorods can be considered as an efficient low cost and recyclable adsorbent for dye removal with efficiency 94% for Cobalt ferrite nanotubes and for Cobalt ferrite porous nanorods equals 95%.

Effects of supplemental different clay minerals in broiler chickens under cyclic heat stress

  • Jaewoo An;Jihwan Lee;Minho Song;Hanjin Oh;Yongju Kim;Seyeon Chang;Youngbin Go;Dongcheol Song;Hyunah Cho;Haeryoung Park;Hyeun Bum Kim;Jinho Cho
    • Journal of Animal Science and Technology
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    • 제65권1호
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    • pp.113-131
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    • 2023
  • The objective of this study was to investigate the effect of supplementing clay minerals and organic chromium in feed on broiler chicken under heat stress (HS). A total of 90 one-day-old broiler chicken (Arbor Acres) with an initial body weight of 45.0 ± 0.2 g were assigned to five treatment groups (six replications, three birds each cage): 1) NC group, basal diet under room temperature environment; 2) PC group, basal diet under high temperature (HT) environment; 3) ILT group, basal diet + 1% illite + HT; 4) ZLT group, basal diet + 1% zeolite + HT; 5) OC group, basal diet + 400 ppb/kg organic chromium + HT. The ILT and ZLT groups had significantly higher body weight than the PC group in 4 weeks. Apparent total tract digestibility of gross energy was increased in the ILT, ZLT, and OC groups compared to the PC group. The NC group had lower foot-pad dermatitis score than other groups. Escherichia coli population in the cecum and feces was decreased in the ZLT group than in the PC group. Lactobacillus in cecum and feces was significantly increased in the ZLT group than in the PC group. Regarding blood profiles, blood cortisol was decreased in the NC and ILT groups compared to the PC group. Water holding capacity and pH were increased in the ZLT group than the PC group. In conclusion, according to the results of growth performance, nutrients digestibility, bacteria counts, and meat characteristics, supplementation of the ZLT in broiler diet can alleviate HS.

제올라이트로부터 스멕타이트 수열 합성에 대한 연구 (Hydrothermal Synthesis of Smectite from Zeolite)

  • 채수천;김유동;장영남;배인국;류경원;이성기
    • 한국광물학회지
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    • 제19권4호
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    • pp.301-310
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    • 2006
  • 수열합성법에 의하여 Na-P 형 및 Na-A형 제올라이트로부터 스멕타이트를 합성하였고 이들의 물리화학적 특성을 연구하였다. 제올라이트로부터 스멕타이트의 최적 합성조건은 반응온도 $290^{\circ}C$, 반응시간 72 h, 자생압력 $75{\sim}100kgf/cm^2$였으며, 스멕타이트의 합성을 위한 초기 반응 용액의 pH는 Na-P형 제올라이트의 경우, pH 6, 그리고 Na-A형 제올라이트의 경우, pH 10이었다. Na-P형 및 Na-A 형 제올라이트로부터 합성된 스멕타이트에 대한 부정방위, 정방위, 에티렌 그리콜 및 Greene-Kelly 시험법 등을 통하여 합성된 스멕타이트가 $12{\AA}$-바이델라이트임을 확인하였으며, 이들의 특성을 연구하였다.

다양한 염도에서 제조한 된장의 장기 숙성 시 품질변화 (Quality characteristics of Doenjang depending on various salt concentration during long-term fermentation period)

  • 최보영;길나영;박신영;김소영
    • 한국식품저장유통학회지
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    • 제23권6호
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    • pp.788-796
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    • 2016
  • 저염 된장 제조를 위하여 염 농도(4, 8, 15, 20%)를 달리하여 12개월의 장기 기간 동안 발효시켜 품질특성 변화를 조사하였다. pH는 모든 염농도의 된장에서 발효 12개월 동안 점차 높아졌는데, 특히 4, 8% 저염 된장에서 급격히 높아졌다. 적정산도는 염 농도가 낮을수록 높아지는 경향을 나타내다가 발효 5개월 이후부터는 저염(4와 8%)된장의 경우는 꾸준히 감소하였으나 고염(15와 20%)의 경우는 증가하여 발효초기와 달리 염농도가 높을수록 높은 값을 나타내었다. 또한 염 농도가 낮을수록 된장 중 아미노태 질소함량은 증가하였고, ${\alpha}-amylase$ 효소활성은 모든 시료에서 발효기간 동안 감소하였다. protease 효소활성은 7개월까지 고염 된장(15, 20%)에 비해 저염 된장(4, 8%)에서 높게 나타났다. 미생물수 변화는 염 농도와 상관없이 발효 12개월 동안 Bacillus속 미생물을 우점종으로 하여 8.0~9.1 log CFU/g의 일정한 총균수를 보였다. pH, 산도, 아미노태 질소함유량은 8% 된장에서 다른 된장보다 높은 값을 나타냈다. 유산균은 발효가 진행되면서 감소되었는데 4% 저염 된장의 경우 9개월 전까지 검출되었다. 맛 센서를 이용한 관능검사에서 8% 된장은 쓴맛과 떫은맛이 낮고 신맛은 약하며 감칠맛은 높아 우수한 품질을 나타내었기에 소금이 저감화 된 장류개발이 가능할 것으로 판단된다.

Effects of Electric Current and Potential on the Electrokinetic Removal of Heavy Metals from an Abandoned Mine Tailings

  • Shin, Hyun-Moo;Lee, Chang-Eun
    • 한국환경과학회지
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    • 제13권2호
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    • pp.149-159
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    • 2004
  • In the removal of heavy metals from the mine deposit using electrokinetic processes, the effects of operation under both constant current and constant potential conditions were estimated. The results of soil pH distributions for DDW-20 V and DDW-100 mA cases after the electrokinetic remediation tests were observed. In the former case, soil pH was not much changed and kept to almost constant value just little higher than initial soil pH of 3.52, except near the cathode, which was about pH 5. While in the latter case, soil pHs of anode and the cathode regions were less than pH 3 and about 6, respectively. The electroosmotic flow to the cathode increased rapidly till 10 hrs and decreased steadily and then maintained to constant rate until the end of operation at constant current condition. Electric potential gradient was continuously increased to as much as 34.375 V/cm. At the steady state, values of the apparent electric conductivity for DDW-20 V and DDW-100 mA were around 40 ${\mu}\textrm{s}$/cm and 30 ${\mu}\textrm{s}$/cm, respectively. In the DDW-100mA test, Cu, Cd, and Zn except Pb showed the tendency of moving toward the cathode. While in the DDW-20 V case, it was observed that Cu, Zn, and Pb except Cd were not moved to any directions. The results of the tests demonstrated that the electrokinetic soil remediation process could be operated better under constant current condition than constant electric potential condition.

벤토나이트의 중금속 흡착에 대한 통계모델의 적용 및 열역학적 해석 (Application of Statistical Model and Thermodynamic Analysis on Sorption of Heavy Metals by Bentonite)

  • 정찬호;김수진
    • 지질공학
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    • 제12권2호
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    • pp.203-214
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    • 2002
  • 벤토나이트의 중금속 흡착에 대한 다양한 실험적 조건을 만족시키기 위하여 박스-벤켄(Box-Benken)의 통계적 모델을 적용하였다. 모델에 의하여 pH, 중금속의 초기농도, HCO$_3$을 변수로 하고, 각 변수에 대한 농도를 3차원으로 설정하여 벳치 실험을 실시하였다. 실험에 선택된 중금속은 Pb, Cu, Zn, Cd 4종이다. 중금속의 흡착거동에 대한 각 변수들의 영향을 표면반응 분석을 통하여 3차원으로 모델링하였다. 중금속의 흡착제거에 중금속의 초기농도와 pH가 거의 비슷한 정도로 큰 영향을 미치고 중탄산은 큰 영향을 미치지 못한다. 중금속간의 흡착경쟁은 Pb>Cu>Zn>Cd의 순서를 보인다. 아울러 pH 변화가 중금속 흡착에 미치는 영향을 실험적 및 열역학적 분석을 통하여 알아보았다. 중금속의 수산화 화합물과 탄산염 복합체의 형태로 침전이 흡착제거에 중요한 변수임이 밝혀졌다. WATEQ4F 열역학 프로그램에 의한 종분포 모델링 결과가 흡착실험결과와 다소 상이함을 보이므로 프로그램의 열역학 자료의 수정이 필요하다.

이온토포레시스를 이용한 levodopa의 경피전달: electroosmosis 및 electrorepulsion의 역할 (Levodopa Transport through Skin using Iontophoresis: the Role of Electroosmosis and Electrorepulsion)

  • 정신애;곽혜선;전인구;오승열
    • Journal of Pharmaceutical Investigation
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    • 제38권1호
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    • pp.31-38
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    • 2008
  • The objective of this work is to study transdermal delivery of levodopa using iontophoresis and evaluate various factors which affect the transdermal transport. Levodopa is unstable in aqueous solution, and, in order to establish a stable condition for levodopa for the duration of experiment, we investigated the stability of levodopa in aqueous solutions of different pHs with/without the addition of dextrose or the application of current. Using stable aqueous solution, we have studied the effect of pH, polarity and penetration enhancer (ethanol) on transdermal flux and compared the results. We also investigated the iontophoretic flux from hydroxypropyl cellulose (HPC) hydrogel. In vitro flux study was performed at $33^{\circ}C$, using side-by-side diffusion cell. Full thickness hairless mouse skin and rat skin were used for this work. Current densities applied were 0.4 or $0.6mA/cm^2$ and current was off after 6 hour application. Stability study showed that levodopa solution with a pH 2.5 or 4.5 maintained the initial concentration of levodopa for 24 hours with the addition of 5% dextrose. However, at pH 9.5, levodopa was unstable and 30 to 40% of levodopa degraded within 24 hours, even with the addition of 5% dextrose. Hydrogel swollen with dextrose added levodopa solution maintained about 97% of the initial concentration of levodopa for 13 days, when stored in $4^{\circ}C$. The application of current did not affect the stability of levodopa in hydrogel. Flux study from levodopa solution with pH 2.5 showed that cathodal delivery of levodopa was higher than passive or anodal delivery. When the pH of the donor solution was 4.5, anodal delivery of levodopa was higher than passive or cathodal delivery. These results seem to indicate that electroosmosis plays more dominant role than electrorepulsion in the flux of levodopa at pH 2.5, and the reverse situation applies for pH 4.5. The passive flux was unexpectedly high for the ionized levodopa. Similar to the results from aqueous solution, cumulative amount of levodopa transported trom HPC hydrogel by cathodal delivery was significantly higher than passive or anodal delivery. The treatment of 70% ethanol cotton ball by scrubbing increased passive, anodal and cathodal flux, with the largest increase for anodal flux. These results indicate that iontophoretic delivery of zwitterion such as levodopa is much complicated than that can be expected from small ionic molecules with single charge. The results also indicate that the balance between electroosmosis and electrorepulsion plays a very important role in the transport through skin.

제2형 근관의 확대에 따른 최종근관장파일 크기의 비교 (A COMPARISON OF MASTER APICAL FILE SIZE ACCORDING TO INSTRUMENTATION IN TYPE II ROOT CANAL)

  • 정은주;이동균;백신영;황호길
    • Restorative Dentistry and Endodontics
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    • 제33권5호
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    • pp.435-442
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    • 2008
  • 제2형의 근관형태를 갖는 치아에서 각각의 근관을 모두 근관장까지 확대한 경우, 여러 확대기구에 따른 최종근관장파일의 크기를 상호 비교하여 얼마나 많은 변화가 있었는지를 분석하고자 치근 우식이 없고 치근단공 형성이 완료되었으며 2개의 근관 입구에서 시작하여 하나의 치근단공을 갖는 제 2형의 근관형태를 보이는 상악 소구치, 상악 대구치의 근심협측 치근 및 하악 대구치의 근심 치근을 선택하여 확대기구에 따라 KF군, PT군, HS군, K3군으로 분류하고 치경부 조기 확대를 시행하였다. 초기근관장파일이 15번 크기인 치아를 각 군당 20개씩 무작위로 선택하였고, 모든 근관을 각 군에 해당되는 30번 크기의 파일까지 제조회사의 지시에 따라 확대를 시행한 후, 촉감과 universal testing machine을 이용하여 최종근관장파일의 크기를 결정하였다. 각 군의 최종근관장파일의 크기와 제거 시 요구되는 힘의 크기에 대한 유의성 검증은 one-way ANOVA를 이용하여 비교 분석하였으며, 사후검정은 Tukey HSD test를 이용하여 0.05의 유의수준에서 분석하였다. 본 연구의 결과 제2형의 근관형태를 갖는 치아의 근관확대 시, 모든 근관을 각각의 근관장으로 확대하는 방법은 확대에 마지막으로 이용된 기구의 크기보다 한, 두 단계 정도 증가된 최종근관장파일을 나타냈다. 그러므로 제2형 근관형태를 나타내는 치아의 근관치료 시 임상가들은 근관충전에 앞서 치근단 받침을 다시 확인하고 형성하는 과정이 필요하리라 사료된다.