• Title/Summary/Keyword: pH measurement test

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Studies on the surface charge and coagulation characteristics of suspended particles in the aqueous phase (수용액상에서 부유 미립자의 표면전위와 응집특성에 관한 연구)

  • 박상원;김성국;홍대일
    • Journal of Environmental Science International
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    • v.8 no.3
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    • pp.363-369
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    • 1999
  • This study aimed to elucidate the relationship between theoretical parameters affecting the coagulation process and the real coagulation phenomenon applied to the dye wastewater. Emphasis was placed on the effective removal of the suspend particulates. Parameters studied in this study are pH, coagulant concentration and surface potential. Optimal dosages of coagulants by the measurement of the zeta potential at lower then $25^{\circ}C$ are 5\times$10^P-3}$ M of $FeCl_3 and 1.4\times10^{-6}M of Fe_2(SO_4)_3$. The results were well agreeded with the separate Jar-test results. Emphasis was also placed on the relationship between water quality and the content of SS. It was found that the COD and DOC were reduced to 65% and 85%, respectively. The turbidity at the above condition was reduced from 300 NTU to 0~1 NTU. Efforts were made to clarify the behavior of the suspend solid as affecting the water quality. 12,000~13,000 particles/10mL in $1~50\mu$m size range particulates in the raw wastewater were reduced to 300 particle/10mL in the same range after treatment. This research has proposed the methodology to find out the optimal condition of coagulation for small scale wastewater treatment plant or chemical coagulation process.

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Quality Characteristics and Storage Stability of Bread with Allium hookeri Powder (삼채가루 첨가 식빵의 제조조건 최적화 및 저장성 연구)

  • Lee, HeeJeong;Baik, Jae-Eun;Joo, Nami
    • The Korean Journal of Food And Nutrition
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    • v.27 no.2
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    • pp.318-329
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    • 2014
  • The purpose of this study was to determine the optimal mixing ratio of Allium hookeri powder and butter in the preparation of bread. The experiment was designed according to the central composite design for estimating the response surface, which demonstrated 10 experimental points, including 2 replicates for Allium hookeri powder and butter. Further, the mechanical and sensory properties of test materials were measured. A canonical form and perturbation plot conveyed the influence of each ingredient on the final product mixture. Overall, the measurement results of the mechanical properties showed a significant increase or decrease in dough pH, sweetness, volume, weight, height, specific volume, a & b-value of crumb and, springiness (p<0.05). Moreover, the sensory measurements demonstrated a significant improvement in color, appearance, texture, moistness and, overall quality. As a result, the optimum formulation from the numerical and graphical methods was calculated as 22.65 g of Allium hookeri powder and 47.77 g butter. After optimization, DPPH free radical scavenging activity, total phenolic content, and total plate counts over 10 days were evaluated. In sum, the results revealed the antioxidant and antibiotic actions of bread with Allium hookeri powder.

Quality Characteristics of Muffins Containing Domestic Blueberry (V. corymbosum) (국내산 블루베리 첨가 머핀의 품질 특성)

  • Hwang, Seung-Hwan;Ko, Seong-Hye
    • Journal of the East Asian Society of Dietary Life
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    • v.20 no.5
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    • pp.727-734
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    • 2010
  • As the blueberry content in batter increased, the pH of batter decreased According to the measured results about specific gravity of muffin batter, there was no significant difference among each batter including 0% 10% and 15% blueberry, while each 15% 20% and 30% dough showed significant difference (p<0.001). According to the results about general quality characteristics of muffins such as volume, weight and specific gravity, as the content of blueberry juice increased, the volume decreased. In terms of measuring specific volume, it decreased as the added amount increased According to measuring the chromaticity of muffins, as the blueberry content increased in the muffins, brightness and yellowness decreased while redness increased In terms of the measurement of texture, the hardness showed significant difference among all sample muffins (p<0.001). Significant difference was not shown in the springiness (p<0.05). As the amount of blueberry juice increased, the chewiness of the muffins was grown. The result showed a significant difference between samples in the adhesiveness (p<0.001). As the amount of blueberry juice increased, the adhesiveness of muffins also increased In the organoleptic test, a significant difference was shown in the color among all sample (p<0.001). The blueberry juice content of 20% showed highest figures with $7.12{\pm}0.67$. In terms of flavor, the content of 20% also showed highest figures among all samples with $7.16{\pm}0.62$ (p<0.001). Concerning the taste all samples showed a significant difference while 20% content did the highest figure. In the overall acceptability the content of 10% showed the lowest figure while 20% displayed the highest figure with 7.16. According to the quality characteristics of blueberry muffins, the best blueberry juice content would be 20% content group.

Fundamental Studies on the Boiling off Test of Raw Silk (생사연감검사에 관한 기초시험)

  • 김현수;이덕로;김영진
    • Journal of Sericultural and Entomological Science
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    • v.13 no.1
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    • pp.69-72
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    • 1971
  • 1. To study proper sample size in boiling-of test, we extracted samples in size of 200, 100, 50, 20, and 10 grams and tested them. In the result of this test we couldn't find a statistical significance among them, but it is seemed that the proper sample size is 100 gram to think about the errors of measurement and treatment when the sample size is either too little or too much in ordinary test. 2. We tested boil-of result by twisted sample skein (sizing skein) and untwisted sample. In this test to use sodium carbonate (Na$_2$CO$_3$) having powerful sericin dissolving power as a scouring agent, boil-off percents made no statistical significance between two kinds of sample skein. And to use marseilles soap having less powerful sericin dissolving power as a scouring agent, boil-off percents made a difference between twisted and untwisted sample skein. 3. We compared five kinds of scouring agent, for example sodium carbonate, monogen, synthetic detergent (HiTi), marseilles soap A (made in Japan) and marseilles soap B (made in Korea). Among them synthetic detergent and marseilles soap B showed no statistical significance compared with marseilles soap A which we used in ordinary boil-off test. So synthetic detergent and marseilles soap B can be substituted for marseilles soap A. 4. Generally the higher pH value of boil of solution, tile more sericin dissolution, showed and vice versa.

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Thyroid Function Test in Thyroid Diseases and Pregnancy - The diagnostic value of free thyroxine by RIA - (임신 및 각종 갑상선질환에서 갑상선 기능 판정에 관한 연구 - 혈청유리 $T_4$의 진단적 의의에 관한 고찰 -)

  • Yoo, M.H.;Yoon, H.J.;Shin, Y.T.;Lee, J.C.;Chung, S.I.;Cho, B.Y.;Lee, M.;Lee, M.C.
    • The Korean Journal of Nuclear Medicine
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    • v.15 no.1
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    • pp.1-11
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    • 1981
  • To evaluate the diagnostic accuracy of the measurement of free thyroxine (FT4) by radioimmunoassay, we measured free $T_4\;and\;T_4,\;T_3,\;T_3RU$, TSH and TBG serum levels by radioimmunoassay in 18 healthy persons and 52 patients with various thyroid diseases and 11 normal pregnant women. The results are as follows. 1. In 19 cases of overt hyperthyroidism, $T_3,\;free\;T_4$ and FTI, $T_4/TBG$ ratio reflect hyperfunction in all cases. $T_4$ is increased in 94% (18/19) and TBG and TSH are decreased in 79% (15/19). 2. In 8 patients with overt hypothyroidism, TSH is increased in all cases and free $T_4$ and FTI is decreased in all cases. $T_4$ is decreased in 87.5% (7/8), $T_3$ is decreased in 75% (6/8) and $T_4/TBG$ ratio is decreased in 62.5% (5/8). 3. In 5 patients who are clinically in euthyroid state after treatment of hyperthyroidism, $T_4,\;free\;T_4$, FTI and TSH are in the normal range in all cases and $T_3$ is normal in 60% (3/5) and slightly increased in 40% (2/5). 4. In 10 patients who showed clinically borderline hypothyroidism after treatment of hyperthyroidism, TSH is increased in all cases and free $T_4$ and FTI are decreased in all cases, but $T_4\;and\;T_3,\;T_4/TBG$ ratio are in the normal limit in all cases. So after treatment of hyperthyroidism, TSH, free $T_4$ or FTI are recommended as optimal thyroid function test. 5. In normal pregnancy, free $T_4$, FTI and $T_4/TBG$ ratio reflect normal function, but the other parameters revealed unreliable due to the influence of increased TBG. Also TBG and TSH level in pregnancy is increased significantly compared with normal healthy control group. 6. The coefficients of correlation between free $T_4$ and FTI were 0.862 (p<0.001) and 0.685 (p<0.001) between free $T_4\;and\;T_4/TBG$ ratio. In most patients, diagnostic value of free $T_4$ was comparable and even superior to FTI, so free $T_4$ measurement can be used routinely with thyrotropin assay in the diagnosis of hypothyrodism or with $T_3$ for the diagnosis of hyperthyroidism.

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Flocculation Kinetics Using Fe(III) Coagulant in Advanced Water Treatment: The Effect of Sulfate Ion (상수처리시 Fe(III) 응집제를 이용한 응집동력학에 관한 연구 : 황산이온의 영향)

  • 강임석;이병헌
    • Journal of Environmental Science International
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    • v.4 no.4
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    • pp.367-377
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    • 1995
  • The study of flocculation kinetics is of fundamental interest in the field of water treatment, because rational study of the factors affecting the coagulation process should be based on the rate of particle growth. The effect of sulfate on flocculation kinetics were examined using ferric nitrate as a coagulant to coagulate kaolin clay in water under several experimental conditions. Both the particle size distribution data obtained from the AIA and the on-line measurement of turbidity fluctuation by the PDA were used to measure flocculation kinetics. Results show that sulfate ion added to the kaolin suspension played an important role in the flocculation process, not only improving flocculation kinetics at more acidic pH levels but also changing surface charge of particles. The kinetics of flocculation were improved mainly by the enhanced rate and extent of Fe(III) precipitation attributed to the addition of sulfate, and thereby, better interparticle collision frequency, but little by the charge reductions resulting from the sulfate addition. The increase in sulfate concentration beyond $3\times10^{-4}M (up to 2\times10^{-3}M)$ did not induce further improvement in flocculation kinetics, although the higher concentrations of sulfate ion substantially increased the negative ZP value of particles. Key Words : Flocculation Kinetics, Fe(III) Coagulant, Sulfate ion, Turbidity Fluctuation.

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Effects of the Substitution of Wet-Milled Rice Flour for Wheat Flour on the Physicochemical Properties and Acceptability of Yellow Layer Cake (습식제분 쌀가루의 첨가가 옐로 레이어 케이크의 이화학 특성과 소비자 기호도에 미치는 영향)

  • Kim, Ji-Young;Jeon, Jae-Eun;Lee, In-Seon
    • Journal of the Korean Society of Food Culture
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    • v.36 no.5
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    • pp.492-501
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    • 2021
  • This study investigated the physicochemical properties and acceptability of yellow layer cake prepared using various levels of wet-milled rice flour (RF). RF was used to substitute 0% (control group), 15% (RF-15 group), 30% (RF-30 group) and 45% (RF-45 group) of wheat flour (WF) to manufacture yellow layer cakes. The substitution of WF with RF showed no significant effect on the pH but decreased the specific gravity and viscosity of the batter. Baking loss rates ranged from 4.65% to 5.03%, showing no significant difference among samples. In the color measurement, the experimental groups showed higher redness (a) and yellowness (b) than the control group (p<0.05). The experimental groups showed lower gumminess and chewiness than the control group. According to the results of intensity measurement of sensory properties, the RF-30 and RF-45 groups showed stronger intensities for darkness, sweetness, moistness and softness than the control group. The acceptance test found that the RF-45 group had significantly higher or similar results for all acceptance attributes than the control group. These results indicate that RF addition as a replacement of WF at a ratio of 45% is optimal for producing yellow layer cakes.

EFFECT OF VARIOUS LINERS ON THE POLYMERIZATION SHRINKAGE OF COMPOSITE RESIN (수종의 이장재가 복합레진의 중합수축에 미치는 영향)

  • Choi, Ji-Won;Lee, Sang-Ho;Lee, Nan-Young
    • Journal of the korean academy of Pediatric Dentistry
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    • v.33 no.4
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    • pp.606-614
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    • 2006
  • The purpose of this study was to evaluate the polymerization contraction of composite resin(Tetric $ceram^{(R)}$, Ivoclar Vivadent Liechtenstein) according to various liners(Tetric $flow^{(R)}$, Ivoclar Vivadent, Liechtenstein/$Ionosit^{(R)}$, DMG, German/ $Vitrebond,^{TM}$ 3M-ESPE, USA). The strain gauge method was used for measurement of polymerization shrinkage strain. Specimens were divided by 8 groups according to curing units and liners. Group A, E: Tetric $ceram^{(R)}$ bulk filing, Group B, F: Tetric $flow^{(R)}$ lining, Tetric $ceram^{(R)}$ filling, Group C, G: $Ionosit^{(R)}$ lining, Tetric $ceram^{(R)}$ filling, Group D, H: $Vitrebond^{TM}$ lining, Tetric $ceram^{(R)}$ filling. Group A, B, C and D were cured using the conventional halogen light($XL3000^{TM}$ 3M ESPE, USA) for 40 seconds at $400mW/cm^2$. Group E, F G and H were cured using light emitted diode(LED) light(Elipar Freelight $2^{TM}$, 3M-ESPE, USA) for 15 seconds at 800 $mW/cm^2$. Strain gauge attached to each sample was connected to a strainmeter. Measurements were recorded at each second for the total of 750 seconds including the periods of light application. Obtained data were analyzed statistically using Repeated measures ANOVA and Tukey test. The results of this were as follows : 1. Contraction stresses in flowable resin and glass ionomer lining group were lower than that in compomer lining group(p<0.05). 2, Contraction stresses in LED curing light groups were higher than that in halogen curing light groups, but there was no significant difference (p>0.05).

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COMPARISON OF CANAL SHAPING METHODS WITH GTTM ROTARY FILE AND CONDENSATION METHODS (GT rotary file을 이용한 근관성형법과 충전방법의 비교)

  • Kang, Yu-Mi;Jin, Jeong-Hee;Yu, Mi-Kyung;Lee, Se-Joon;Lee, Kwang-Won
    • Restorative Dentistry and Endodontics
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    • v.27 no.5
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    • pp.521-529
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    • 2002
  • The purpose of this study was to compare the shaping time of two shaping methods and the leakage of three different obturation techniques. Ninty three canaled human molar teeth were used, which were randomly divided into two groups of forty teeth each and ten control teeth. After working length determination, the one group was prepared crown-down technique using rotary root canal instruments of GT rotary files .12/20, .10/20, .08/20 and .06/20 taper(Maillefer Instrument SA. Switzerland). The other group was instrumented with Gates Glidden burs(#1, #2, and #3) to coronal preparation and GT rotary files .08/20 and .06/30 taper to apical preparation. Shaping time was measured. After root canals were instrumented, they were divided to three subgroups and obturated as follows : Subgroup 1, obturated with single cone method Subgroup 2, obturated with lateral condensation : Subgroup 3, obturated with continuous wave technique. Three subgroups were obturated using non-standardized gutta-percha cone(Diadent, Korea, .06 or .08 taper) and AH-26(Dentsply DeTrey, Germany) as a root canal cement. Ten unobturated teeth served as positive and negative controls. After immersion in 2% methylene blue solution for 1 month, the teeth were washed during 24h. The teeth were demineralized in 10% nitric acid and dehydrated by immersion in 80, 90 and 100% ethyl alcohol. The teeth were finally cleared and stored in 100% methylsalicylate, and apical dye penetration was evaluated under stereomicroscope(Leica M420, LC, U.S.A)at $\times$8.75 magnification. Liner measurement of dye penetration was assessed with the use of digitalized image analysing system (analySIS, GmbH, Germany) The data were analysed statistically using independent T-test and Two-way ANOVA and Tukey test. The result were as follows 1. In canal prepared with GT$^{TM}$ rotary file, shaphing time taked more than the group of using Gates Glidden drill to coronal preparation without statistical significance (p>0.05) 2. The group of single cone obturation using canal preparation of GT$^{TM}$ rotary files showed significantly more apical leakage than those of lateral condensation and continuous wave technique regardless of shaping method (p<0.05). 3 The group of single cone obturation using canal preparation of GT$^{TM}$ rotary files and Gates Glidden drill showed significantly more apical leakage than those of continuous wave technique regardless of shaping method (p<0.05). 4. Regardless of shaping method, The group of continuous wave obturation showed less apical leakage than those of lateral condensation without statistical significance (p>0.05). 5. The group of single cone obturation using canal preparation of GT$^{TM}$ rotary files and Gates Glidden drill showed more apical leakage than the group of lateral condensation using same shaping method with-out statistical significance (p>0.05).

Determination of Efficient Operating Condition of UV/H2O2 Process Using the OH Radical Scavenging Factor (수산화라디칼 소모인자를 이용한 자외선/과산화수소공정의 효율적인 운전 조건도출)

  • Kim, Seonbaek;Kwon, Minhwan;Yoon, Yeojoon;Jung, Youmi;Hwang, Tae-Mun;Kang, Joon-Wun
    • Journal of Korean Society of Environmental Engineers
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    • v.36 no.8
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    • pp.534-541
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    • 2014
  • This study investigated a method to determine an efficient operating condition for the $UV/H_2O_2$ process. The OH radical scavenging factor is the most important factor to predict the removal efficiency of the target compound and determine the operating condition of the $UV/H_2O_2$ process. To rapidly and simply measure the scavenging factor, Rhodamine B (RhB) was selected as a probe compound. Its reliability was verified by comparing it with a typical probe compound (para-chlorobenzoic acid, pCBA); the difference between RhB and pCBA was only 1.1%. In a prediction test for the removal of Ibuprofen, the RhB method also shows a high reliability with an error rate of about 5% between the experimental result and the model prediction using the measured scavenging factor. In the monitoring result, the scavenging factor in the influent water of the $UV/H_2O_2$ pilot plant was changed up to 200% for about 8 months, suggesting that the required UV dose could be increased about 1.7 times to achieve 90% caffeine removal. These results show the importance of the scavenging factor measurement in the $UV/H_2O_2$ process, and the operating condition could simply be determined from the scavenging factor, absorbance, and information pertaining to the target compound.