• Title/Summary/Keyword: time-temperature curve

Search Result 391, Processing Time 0.031 seconds

Preservative characteristics of photographic films and papers on the speed method (사진용 필름, 인화지의 감도측정에 따른 보존특성)

  • Ahn, Hong-Chan;Han, Sang-Wan;Choi, Hoon-Jeong;Heo, Hoon
    • Journal of Korean Society of Archives and Records Management
    • /
    • v.3 no.2
    • /
    • pp.143-155
    • /
    • 2003
  • As archives, photograph is the evident records of historical facts and experiences. Thus, it is worth preserving. Unlike other documents silver halide photographic films and prints are quite sensitive to environmental factors such as light, temperature and humidity, which demands careful treatment in preservation. This study was carried out to select popular photographic films and papers on the market, to examine their photographic speeds (or sensitivities) and to compare and analyze their preservative features after keeping them some time in a weather-o-meter. Consequently, B/W materials were superior to color ones in preservation. And films were better than papers in the same manner. But we were not able to observe remarkable differences among material's manufacturers.

Development of Highly Sensitive Analytical Method for Evaluation of Evening Primrose Oil's Enhancing Effect in Prostaglandin E1(OP 1206) Biosynthesis

  • Lee, Sung-Hoon
    • Journal of People, Plants, and Environment
    • /
    • v.21 no.6
    • /
    • pp.485-492
    • /
    • 2018
  • This study aimed to develop and validate highly sensitive determination method of a prostaglandin ($PGE_1$, OP 1206) in human plasma by LC-MS/MS using column switching. Plasma stored at $-30^{\circ}C$ and treated with methanol effectively inhibited interferences synthesized post-sampling. Samples were added with internal standard and were separated by reversed-phase HPLC with a cycle time of 30min. The method was selective for OP 1206 and the regression models, based on internal standard, were linear across the concentration range 0.5-50 pg/mL with the limit of quantification of 0.5 pg/mL (limit of quantitation, LOQ) for OP 1206. The calibration curve of OP 1206 standards spiked in five individual plasma samples was linear ($r^2=0.9999$). Accuracy and precision at the concentrations of 0.5, 1.5, 5.0 and 40 pg/mL, and at the lower LOQ of 0.5 pg/mL were excellent at 20%. OP120 < 6 was stable in plasma samples for at least 24 hours at room temperature, 24 hours frozen at $-70^{\circ}C$, 24 hours in an auto sampler at $6^{\circ}C$, and for two freeze/unfreezing cycles. The validated determination method successfully quantified the concentrations of OP 1206 in plasma samples from simulated administrating a single $5{\mu}g$ OP 1206 formulation. Thus, this novel LC-MS/MS technique for drug separation, detection and quantitation is expected to become the standard highly-sensitive detection method in bioanalysis and to be applied to many low dose pharmaceutical products.

Dyeability of Nylon Fabrics with Dyestuff for Supercritical Fluid Dyeing (1) : C.I. Disperse Red 167, C.I. Disperse Violet 93 (초임계 유체 염색용 염료에 따른 Nylon 섬유의 염색 특성 (1) : C.I. Disperse Red 167, C.I. Disperse Violet 93 Azo계 염료)

  • Choi, Hyunseuk;Park, Shin;Kim, Taeyoung
    • Textile Coloration and Finishing
    • /
    • v.32 no.4
    • /
    • pp.217-225
    • /
    • 2020
  • In this study, the dyeing characteristics of nylon fabric which is dyed with supercritical fluid were investigated. There were two dyes used in the dyeing experiment: C.I. Disperse Red 167 and C.I. Disperse Violet 93. Dyeing temperature, pressure, and leveling time were fixed at 110℃, 250bar, 60minutes, and the experiment was conducted with dyeing concentration of 0.1, 0.3, 0.5, and 0.85% o.w.f. The analysis of the experimental results was found out through the measurement of washing fastness and color coordinate. In addition, the calibration curve of each dye was drawn up and the amount of remaining dye was checked by measuring the absorbance of the residual dye. As a result of color difference measurement, as the concentration increased, the L⁎ value decreased and the K/S value increased. However, the increase in K/S value compared to the amount of input decreased as the concentration increased. The comparative experiment on the amount of residual dye(C.I. Disperse Red 167) in the pot showed that 99.14% of the amount was dyed at the concentration of 0.1% o.w.f, while it rapidly decreased to 77% at 0.85% o.w.f. C.I. Disperse Violet 93 dye also decreased from 0.5% o.w.f to 93.91%. In the washing fastness experiment of both dyes, the level of washing fastness began to decrease from samples dyed at 0.5% o.w.f. It may be because the simply absorbed dye was produced instead of completely being fixed in the amorphous region of the nylon fiber.

Qualitative and quantitative assessment of process related impurities in Brigatinib raw material and formulations using HPLC

  • Attada Tharun;Potnuru Jagadeesh;B Srinivasa Kumar;Kota Thirumala Prasad;Venkateswara Rao Anna
    • Analytical Science and Technology
    • /
    • v.36 no.4
    • /
    • pp.180-190
    • /
    • 2023
  • The presence of process related impurities in any drug or the drug product was associated with its safety, stability and efficacy. The overall literature survey proved that there is no method published on the assessment of process related impurities in brigatinib. In this study, a simple, reliable and stable HPLC qualitative method was reported for quantification of process related impurities with easy and quick extraction procedure. The impurities along with standard brigatinib was resolved on Lichrospher® C18 (250 mm × 4.6 mm; 5 ㎛ particle size) column in room temperature using methanol, acetonitrile, pH 4.5 phosphate buffer in 55:25:20 (v/v) at 1.0 mL/min as mobile phase and UV detection at 261 nm. The method produces well resolved peaks at retention time of 4.60 min, 12.28 min, 3.37 min, 7.34 min and 8.39 min respectively for brigatinib, impurity A, B, C and D. The method produces a very sensitive detection limit of 0.0065 ㎍/mL, 0.0068 ㎍/mL, 0.0053 ㎍/mL and 0.0058 ㎍/mL for impurity A, B, C and D respectively with calibration curve linear in the concentration range of 22.5-135 ㎍/mL for brigatinib and 0.0225-0.135 ㎍/mL for impurities. The method produces all the validation parameters under the acceptable level and doesn't produces any considerable changes in peak area response while minor changes in the developed method conditions. The method can effectively resolve the unknown stress degradation products along with known impurities with less % degradation. The method can efficiently resolve and quantify the impurities in formulation and hence can suitable for the routine quality analysis of brigatinib in raw material and formulation.

Cryosurgery of Lung with 2.4 mm Cryoprobe: An Experimental in vivo Study of the Cryosurgery in Canine Model (냉동침을 이용한 폐 냉동수술의 동물실험: 냉동수술 방법의 비교 실험)

  • Kim Kwang-Taik;Chung Bong-Kyu;Lee Sung-Ho;Cho Jong-Ho;Son Ho-Sung;Fang Young-Ho;Sun Kyung;Park Sung-Min
    • Journal of Chest Surgery
    • /
    • v.39 no.7 s.264
    • /
    • pp.520-526
    • /
    • 2006
  • Background: The clinical application of cryosurgery the management of lung cancer is limited because the response of lung at low temperature is not well understood. The purpose of this study is to investigate the response of the pulmonary tissue at extreme low temperature. Material and Method: After general anesthesia the lungs of twelve Mongrel dogs were exposed through the fifth intercostal space. Cryosurgical probe (Galil Medical, Israel) with diameter 2.4 mm were placed into the lung 20 mm deep and four thermosensors (T1-4) were inserted at 5 mm intervals from the cryoprobe. The animals were divided into group A (n=8) and group B (n=4). In group A the temperature of the cryoprobe was decreased to $-120^{\circ}C$ and maintained for 20 minutes. After 5 minutes of thawing this freezing cycle was repeated. In group B same freezing temperature was maintained for 40 minutes continuously without thawing. The lungs were removed for microscopic examination on f day after the cryosurgery. In four dogs of the group A the lung was removed 7 days after the cryosurgery to examine the delayed changes of the cryoinjured tissue, Result: In group A the temperatures of T1 and T2 were decreased to the $4.1{\pm}11^{\circ}C\;and\;31{\pm}5^{\circ}C$ respectively in first freezing cycle. During the second freezing period the temperatures of the thermosensors were decreased lower than the temperature during the first freezing time: $T1\;-56.4{\pm}9.7^{\circ}C,\;T2\;-18.4{\pm}14.2^{\circ}C,\;T3\;18.5{\pm}9.4^{\circ}C\;and\;T4\;35.9{\pm}2.9^{\circ}C$. Comparing the temperature-distance graph of the first cycle to that of the second cycle revealed the changes of temperature-distance relationship from curve to linear. In group B the temperatures of thermosensors were decreased and maintained throughout the 40 minutes of freezing. On light microscopy, hemorrhagic infarctions of diameter $18.6{\pm}6.4mm$ were found in group A. The infarction size was $14{\pm}3mm$ in group B. No viable cell was found within the infarction area. Conclusion: The conductivity of the lung is changed during the thawing period resulting further decrease in temperature of the lung tissue during the second freezing cycle and expanding the area of cell destruction.

Estimation of Shoot Development for a Single-stemmed Rose 'Vital' Based on Thermal Units in a Plant Factory System (식물공장 시스템에서 Thermal Units을 이용한 Single-Stemmed Rose 'Vital'의 신초발달 예측)

  • Yeo, Kyung-Hwan;Cho, Young-Yeol;Lee, Yong-Beom
    • Horticultural Science & Technology
    • /
    • v.28 no.5
    • /
    • pp.768-776
    • /
    • 2010
  • This study was conducted to predict number and fresh weight of leaves, and total leaf area of a single-stemmed rose 'Vital' based on the accumulated thermal units, and to develop a model of shoot development for the prediction of the time when the flowering shoot reaches a phenological stage in a plant factory system. The base temperature ($T_b$), optimum temperature ($T_{opt}$), and maximum temperature ($T_{max}$) were estimated by regressing the rate of shoot development against the temperature gradient. The rate of shoot development ($R$, $d^{-1}$) for the phase from cutting to bud break (CT-BB) was best described by a linear model $R_b$ ($d^{-1}$) = -0.0089 + $0.0016{\cdot}temp$. The rate of shoot development for the phase from bud break to harvest (BB-HV) was fitted to the parabolic model $R_h$ ($d^{-1}$) = $-0.0001{\cdot}temp^2$ + $0.0054{\cdot}temp$ - 0.0484. The $T_b$, $T_{opt}$, and $T_{max}$ values were 5.56, 27.0, and $42.7^{\circ}C$, respectively. The $T_b$ value was used in the thermal unit computations for the shoot development. Number of leaves, leaf area (LA), and leaf fresh weight showed sigmoidal curves regardless of the cut time. The shoot development and leaf area model was described as a sigmoidal function using thermal units. Leaf area was described as LA = 578.7 $[1+(thermal units/956.1)^{-8.54}]^{-1}$. Estimated and observed shoot length and leaf fresh weight showed a reasonably good fit with 1.060 ($R^2=0.976^{***}$) and 1.043 ($R^2=0.955^{***}$), respectively. The average thermal units required from cutting to transplant and from transplant to harvest stages were $426{\pm}42^{\circ}C{\cdot}d$ and $783{\pm}24^{\circ}C{\cdot}d$, respectively.

Preparation and Bioequivalence Test of Acetaminophen Liquid Suppository (아세트아미노펜 액상좌제의 제초 및 생물학적 동등성 평가)

  • 김종국;최한곤;이사원;고종호;이미경
    • Biomolecules & Therapeutics
    • /
    • v.6 no.2
    • /
    • pp.213-218
    • /
    • 1998
  • A novel in situ-gelling and mucoadhesive acetaminophen liquid suppository was developed to improve the patient compliance of conventional solid suppository. In this study, acetaminophen liquid suppository, Likipe $n_{R}$, [aminophen/Poloxamer 407/Poloxamer 188/so4ium alginate (5/15/19/0.6%)] with relation temperature at 30-36 "C and suitable gel strength and bioadhesive force, dissolution pattern similar to conventional solid type suppository, Suspe $n_{R}$, was developed. Furthermore, the bioequivalence of two acetaminophen products was evaluated in 16 normal male volunteers (age 22-27 yr, body weight 56-72 kg) following sidle rectal administration. Test product was Likipe $n_{R}$ suppository (Dong-Wha Pharm. Corp., Korea)and reference product was Suspe $n_{R}$204-212 suppository (Hanmi Pharm. Corp., Korea). Both products contain 125 mg of acetaminophen. Four Suppositories of the test and the reference product were administered to the volunteers, respectively, by randomized two period cross-over study (2$\times$2 Latin square method). The determination of acetaminophen was accomplished using HPLC. Average drug concentrations at each sampling time and pharmacokinetic parameters calculated were not significantly different between two products (p>0.05); the area under the curve to last sampling time (24 hr) (AU $Co_{-2}$4h/) (30.14$\pm$8.64 vs 27.98$\pm$ 6.53 $\mu$g .h/ml), maximum plasma concentration ( $C_{max}$) (3.29$\pm$0.87 vs 3.60$\pm$0.66 $\mu$g/ml) and time to maximum plasma concentration ( $T_{max}$) (2.91 $\pm$0.55 vs 2.69$\pm$0.60 h). The differences of mean AUCo $_{24h}$, C-a. and T-between the two products (7.18%, 9.58% and 7.53%, respectively) were less than 20%. The power (1-7) and treatment difference ($\Delta$) for AU $Co_{24h}$, $C_{max}$ and $T_{max}$ were more than 0.8 and less than 0.2, respectively at $\alpha$=0.1. The confidence limits for AU $Co_{24h}$, $C_{max}$ and $T_{max}$ (-0.81 ~13.55%, -1.56~ 17.60 and -3.81 ~18.87%, respectively) were less than $\pm$ 20% at $\alpha$=0.1. These results suggest that the bioavailability of Likipe $n_{R}$ suppository is not significantly different from that of Suspe $n_{R}$ suppsitory. Therefore, two products are bio-equivalent based on the current results.results.lts.sults.results.lts.

  • PDF

Population Phenology and an Early Season Adult Emergence model of Pumpkin Fruit Fly, Bactrocera depressa (Diptera: Tephritidae) (호박과실파리 발생생태 및 계절초기 성충우화시기 예찰 모형)

  • Kang, Taek-Jun;Jeon, Heung-Yong;Kim, Hyeong-Hwan;Yang, Chang-Yeol;Kim, Dong-Soon
    • Korean Journal of Agricultural and Forest Meteorology
    • /
    • v.10 no.4
    • /
    • pp.158-166
    • /
    • 2008
  • The pumpkin fruit fly, Bactrocera depressa (Tephritidae: Diptera), is one of the most important pests in Cucurbitaceae plants. This study was conducted to investigate the basic ecology of B. depressa, and to develop a forecasting model for predicting the time of adult emergence in early season. In green pumpkin producing farms, the oviposition punctures caused by the oviposition of B. depressa occurred first between mid- and late July, peaked in late August, and then decreased in mid-September followed by disappearance of the symptoms in late September, during which oviposition activity of B. depressa is considered active. In full-ripened pumpkin producing farms, damaged fruits abruptly increased from early Auguest, because the decay of pumpkins caused by larval development began from that time. B. depressa produced a mean oviposition puncture of 2.2 per fruit and total 28.8-29.8 eggs per fruit. Adult emergence from overwintering pupae, which was monitored using a ground emergence trap, was first observed between mid- and late May, and peaked during late May to early June. The development times from overwintering pupae to adult emergence decreased with increasing temperature: 59.0 days at $15^{\circ}C$, 39.3 days at $20^{\circ}C$, 25.8 days at$25^{\circ}C$ and 21.4 days at $30^{\circ}C$. The pupae did not develop to adult at $35^{\circ}C$. The lower developmental threshold temperature was calculated as $6.8^{\circ}C$ by linear regression. The thermal constant was 482.3 degree-days. The non-linear model of Gaussian equation well explained the relationship between the development rate and temperature. The Weibull function provided a good fit for the distribution of development times of overwintering pupae. The predicted date of 50% adult emergence by a degree-day model showed one day deviation from the observed actual date. Also, the output estimated by rate summation model, which was consisted of the developmental model and the Weibull function, well pursued the actual pattern of cumulative frequency curve of B. depressa adult emergence. Consequently, it is expected that the present results could be used to establish the management strategy of B. depressa.

Characteristics of Anion Exchange Measured by the Rate of Hemolysis in Human Erythrocyte (사람의 적혈구에서 용혈성을 이용하여 측정한 음이온 교환특성)

  • Woo, Jae-Suk;Kim, Yong-Keun;Hwang, Il-Yong
    • The Korean Journal of Physiology
    • /
    • v.20 no.2
    • /
    • pp.218-224
    • /
    • 1986
  • The characteristics of anion exchange with internal $HCO_3\;^{-}\;(or\;OH^-)$ was studied by determining the time course of hemolysis in isoosmotic ammonium salt solution in human erythrocytes. The effects of inhibitors, pH and temperature on the exchange between internal $HCO_3\;^-\;(or\;OH^-)$ and external $Cl^-$ were observed and the permeabilities of various organic and inorganic anions were also measured. The results were compared with data previously reported from the experiments using radioisotopes. The results are as follows; 1) SITS $H_2DIDS$ and furosemide inhibited the hemolysis of erythrocytes in isoosmotic $NH_4Cl$ solution in a dose·dependent manner, and the concentrations for lengthening twice the time for $half-hemloysis(t_{1/2})\;were\;2.3{\times}10^{-7},\;1.3{\times}10^{-7}\;and\;2.5{\times}10^{-5}M$, respectively. 2) Acetazolamide also shifted the time-dependent hemolytic curve to the right in a dose-dependent manner, and the concentrations for lengthening twice $t_{1/2}\;was\;2.4{\times}10^{-5}M$. 3) The time-dependent hemolysis was delayed by decreasing pH from 7.0 to 6.2, but w·as not affected by the change of pH in the range of 7.0 to 8.2. 4) The time for $half-hemloysis(t_{1/2})$ showed a temperature-dependency and Arrhenius plot exhibited a break point at $20^{\circ}C$. The apparent activation energy calculated from this plot was 18.1 kcal/mol between $2^{\circ}C-20^{\circ}C$ and 11.2 kcal/mol between $20^{\circ}C-37^{\circ}C$, respectively. 5) The apparent permeabilities of various inorganic anions based on $t_{1/2}$ were in the order of $Cl^->NO_{3}\;^->SCN^->SO_4\;^{2-}>SSO_3\;^{2-}>HPO_4\;^{2-}$. which was similar with the previous reports based on the experiment using radioisotopes. The results Obtained from this study are comparable with the previous data reported from the experiments using radioisotopes. This indicates that the hemolysis of erythrocytes in isoosmotic ammonium salt solution can be used as a simple and good method for the study of anion exchange in erythrocyte membrane.

  • PDF

A Study on Safety Estimation of Railroad Wheel (컨테이너 철도차륜의 안전성 평가에 관한 연구)

  • Lee, Dong-Woo;Kim, Jin-Nam;Cho, Seok-Swoo
    • Journal of the Korea Academia-Industrial cooperation Society
    • /
    • v.11 no.4
    • /
    • pp.1178-1185
    • /
    • 2010
  • Recently, high speed of container freight cars is causing fatigue damage of wheel. Sudden failure accidents cause a lot of physical and human damages. Therefore, damage analysis for wheel prevents failure accident of container freight car. Wheel receives mechanical and thermal loads at the same time while rolling stocks are run. The mechanical loads applied to wheel are classified by the horizontal load from contact of wheel and rail in curve line section and by the vertical force from rolling stocks weight. Also, braking and deceleration of rolling stocks cause repeated thermal load by wheel tread braking. Specially, braking of rolling stocks is frictional braking method that brake shoe is contacted in wheel tread by high breaking pressure. Frictional heat energy occurs on the contact surface between wheel tread and brake shoe. This braking converts kinetic energy of rolling stocks into heat energy by friction. This raises temperature rapidly and generates thermal loads in wheel and brake shoe. There mechanical and thermal loads generate crack and residual stress in wheel. Wetenkamp estimated temperature distribution of brake shoe experimentally. Donzella proposed fatigue life using thermal stress and residual stress. However, the load applied to wheel in aforementioned most researches considered thermal load and mechanical vertical load. Exact horizontal load is not considered as the load applied to wheel. Therefore, above-mentioned loading methods could not be applied to estimate actual stress applied to wheel. Therefore, this study proposed safety estimation on wheel of freight car using heat-structural coupled analysis on the basis of loading condition and stress intensity factor.