• 제목/요약/키워드: salt sensitivity

검색결과 113건 처리시간 0.027초

난백의 숙감수성에 관한 연구 II. 금속염의 첨가와 pH가 난백의 열감수성에 미치는 영향 (Studies on Heat Sensitivity of Egg Albumen II. Effects of pH and/or the Addition of Metal ions on Heat Sensitivity of Egg Albumen)

  • 유익종;이성기;김영붕
    • 한국가금학회지
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    • 제16권1호
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    • pp.17-22
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    • 1989
  • 난백의 열광수성을 순화시키기 위하여 각종금속염(Fe$^{2+}$, Fe$^{3+}$ , $Al^{3+}$ , Cu$^{2+}$)을 첨가하고 가훈처리($60^{\circ}C$, 5분간) 전후 난백의 기능성을 검토하였으며 알루미늄염(Al$^{3+}$ )이 첨가된 난백의 pH에 대한효과도 검토하였다. 금속염의 첨가에 의해 가열처리 전후 난백의 탁도는 대체로 증가하였으나 알루미늄염의부가시 탁도의 변화가 가장 작았다. 난백의 기포력은 금속염의 첨가에 의해 전반적으로 증가하였으며 Fe$^{3+}$ 의 첨가효과가 가장 컸다. 특히 가열처리 후 난백의 기포력은Fe$^{3+}$ , Al/ sup 3+/ 및 Cu$^{2+}$의 첨가에 의해 크게 증가되었다. 기포안정성의 경우 열처리 전에는 Fe$^{3+}$ , Al/ sup 3+/의 첨가효과가 있었으나 열처리 후에는 Fe$^{3+}$ 와 Al/ sup 3+/의 첨가가 효과적이었다. 한편 알루미늄염을 첨가한 난백을 pH 7 -10의 범위에서 가열처리한 결과 pH 7-8.5 범위에서는 탁도 및 기포성의 변화가 크지 않았고 pH 9이상에서는 탁도와 기포성은 낮아졌으나 기포안정성은 향상되었다. 난백액에 Salmonella typhimurium을 $10^{6}$ cells/$m\ell$수준으로 접종 후 $60^{\circ}C$, 5분간의 가열처리 결과 pH에 상관없이 모두 사멸되었다.

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Sensitivity analysis and Taguchi application in vacuum membrane distillation

  • Upadhyaya, Sushant;Singh, Kailash;Chaurasia, Satyendra Prasad;Baghel, Rakesh;Singh, Jitendra Kumar;Dohare, Rajeev Kumar
    • Membrane and Water Treatment
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    • 제9권6호
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    • pp.435-445
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    • 2018
  • In this work, desalination experiments were performed on vacuum membrane distillation (VMD). Process parameters such as feed flow rate, vacuum degree on permeate side, feed bulk temperature and feed salt concentration were optimized using sensitivity analysis and Taguchi method. The optimum values of process parameters were found to be 2 lpm of feed flow rate, $60^{\circ}C$ of feed bulk temperature, 5.5 kPa of permeate-side pressure and 5000 ppm of salt concentration. The permeate flux at these conditions was obtained as $26.6kg/m^2{\cdot}hr$. The rejection of salt in permeate was found to be 99.7%. The percent contribution of various process parameters using ANOVA results indicated that the most important parameter is feed bulk temperature with its contribution of 95%. The ANOVA results indicate that the percent contribution of permeate pressure gets increased to 5.384% in the range of 2 to 7 kPa as compared to 0.045% in the range of 5.5 to 7 kPa.

활선염해 측정장치 개발연구 (Study on the Laser Salt Meter)

  • 진윤식;김희제;정상진;윤진열
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 1994년도 하계학술대회 논문집 C
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    • pp.1636-1638
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    • 1994
  • Salt deposited on the surface of insulators used in electric power system causes flash-over accidents. Therefore, the quantity of salt on insulators should be monitored not to exceed a critical value. We propose a new remote sensing technique to measure the quantity of salt on insulators of power systems. A pulsed laser beam is focussed on ah insulator to dissociate the salt to sodium atoms. The amount of the salt is measured from the intensity of the spontaneous mission from the sodium atoms. In this paper, a compact salt meter composed of pulsed Nd:YAG laser and omission signal detection system will be introduced. And measurement condition such as the sensitivity, detection range, required laser fluence will be investigated.

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Contribution of lysine-containing cationic domains to thermally-induced phase transition of elastin-like proteins and their sensitivity to different stimuli

  • Jeon, Won-Bae
    • BMB Reports
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    • 제44권1호
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    • pp.22-27
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    • 2011
  • A series of elastin-like proteins, $SKGPG[V(VKG)_3VKVPG]_n$-(ELP1-90)WP (n = 1, 2, 3, and 4), were biosynthesized based on the hydrophobic and lysine linkage domains of tropoelastin. The formation of self-assembled hydrophobic aggregates was monitored in order to determine the influence of cationic segments on phase transition properties as well as the sensitivity to changes in salt and pH. The thermal transition profiles of the proteins fused with only one or two cationic blocks (n = 1 or 2) were similar to that of the counterpart ELP1-90. In contrast, diblock proteins that contain 3 and 4 cationic blocks displayed a triphasic profile and no transition, respectively. Upon increasing the salt concentration and pH, a stimulus-induced phase transition from a soluble conformation to an insoluble aggregate was observed. The effects of cationic segments on the stimuli sensitivity of cationic bimodal ELPs were interpreted in terms of their structural and molecular characteristics.

농촌 노인의 맛 감지능 및 맛 기호도와 짠음식 기호도 (Association between Preferences of Salty Food and Acuity and Preferences of Taste of the Elderly People Living in Rural Area)

  • 이미숙
    • 대한지역사회영양학회지
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    • 제18권3호
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    • pp.223-232
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    • 2013
  • The purpose of the study was to investigate the influence of salt (NaCl) recognition threshold and pleasant salt concentrations of Korean rural elderly subjects on preference of salty food as well as food group consumption patterns. The subjects were 213 elderly people (male 71 and female 142) over 65 and under 90 yr of age from Sunchang area. The higher values were found with male subjects in the areas of basic taste recognition threshold and pleasant concentration level of salt. The taste sensitivity scores of male subjects did not decrease with the increasing age, but female subjects exhibited a significant decrease with the age. The major determinant factor of salt preference of the elderly subjects in this study appeared to be personal pleasant concentration of salt rather than salt recognition threshold level and this trend was more evident in males than in females. The subject group of lower salt pleasant concentration i.e. consuming less salt showed the higher number of fruit and fruit juice intakes per week, and higher MNA (define this) scores were implying that they display more desirable nutritional status. Therefore, nutritional education focused on not only a variety of food consumption but also lowering pleasant salt concentration levels is advised to improve the quality of nutrition in the elderly.

전통 장류의 염도 및 당도가 농촌 노인의 맛 감지도와 식품섭취행태에 미치는 영향 (Salinity and Sweetness of Korean Jang Products related to Taste Threshold, Preferences of Food Group and Nutrient Intakes in the Rural Elderly)

  • 오세인;이미숙
    • 한국식품영양학회지
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    • 제30권4호
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    • pp.780-787
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    • 2017
  • The consumption of high-salt foods is an independent risk factor for increased hypertension. Thus, evaluating the relationship of taste sensitivity and pleasantness of high-salt foods such as Korean jang products, would help contribute to an understanding of salty food eating behaviors of the Korean rural elderly. This study aimed to verify the association between taste sensitivity and salinity of Korean jang products, and the preferences of food groups and nutrient intake in the rural elderly. We studied 269 elderly persons (males 83, females 186) aged above 65 years, residing in the rural area, Sunchang gun Jeonbuk. For each subject, a recognition threshold of 4 basic tastes and pleasant concentrations of NaCl were estimated using the sip- and-spit method. Taste preferences, frequency of intake of food groups, nutrient intakes, and salinity and sweetness of Korean jang products (Doenjang, Ganjang, Gochujang) were assessed. No association was found between salt taste recognition threshold and optimally preferred concentration of salt and salinity of Korean jang products. However, the sweet taste recognition threshold was positively related to the sweetness of Korean jang products. Also, the salinity of Doenjang positively correlated with the frequencies of food groups and nutrient intakes. That is to say that the sweet taste sensitivity was related to the sweetness of Korean jang products, but was not sensitive to the salty taste. The salinity of Doenjang correlated with the consumption of food and nutrient intakes. Taken together, these findings suggest the need for appropriate intervention and education to reduce the salinity of Doenjang, which is an important modifiable factor contributing to reducing sodium intake in the rural elderly.

Role of Tyrosine Kinases in Vascular Contraction in Deoxycorticosterone Acetate-Salt Hypertensive Rats

  • Yeum, Cheol-Ho;Jun, Jae-Yeoul;Choi, Hyo-Sub
    • The Korean Journal of Physiology and Pharmacology
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    • 제1권5호
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    • pp.547-553
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    • 1997
  • It has been known that activation of tyrosine kinases is involved in signal transduction. Role of the tyrosine kinase in vascular smooth muscle contraction was examined in deoxycorticosterone acetate (DOCA)-salt hypertensive rats. Male Sprague-Dawley rats underwent uninephrectomy, one week after which they were subcutaneously implanted with DOCA (200 mg/kg) and supplied with 1% NaCl and 0.2% KCl drinking water for $4{\sim}6$ weeks. Control rats were treated the same except for that no DOCA was implanted. Helical strips of carotid arteries were mounted in organ baths for measurement of isometric force development. Genistein was used as a tyrosine kinase inhibitor. Concentration-response curves to 5-hydroxytryptamine (5-HT) shifted to the right by genistein in both DOCA-salt hypertensive and control rats. Although the sensitivity to genistein was similar between the two groups, the maximum force generation by 5-HT was less inhibited by genistein in arteries from DOCA-salt hypertensive rats than in those from controls. Genistein-induced relaxations were attenuated in arteries from DOCA-salt rats. Genistein affected the contraction to phorbol 12, 13-dibutyrate (PDBu) neither in DOCA-salt nor in control arteries. These observations suggest that tyrosine kinase is involved in 5-HT-induced vascular contraction, of which role is reduced in DOCA-salt hypertension.

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Biomass partitioning and physiological responses of four Moroccan barley varieties subjected to salt stress in a hydroponic system

  • Said Bouhraoua;Mohamed Ferioun;Srhiouar Nassira;Abdelali Boussakouran;Mohamed Akhazzane ;Douae Belahcen;Khalil Hammani;Said Louahlia
    • Journal of Plant Biotechnology
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    • 제50권
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    • pp.115-126
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    • 2023
  • A hydroponics experiment was performed to study the physiological and biochemical changes in Moroccan barley (Hordeum vulgare L.) varieties cultivated under salt stress conditions. Four barley varieties were grown under exposure to three salt concentrations, including 0, 200, and 300 mM NaCl. The ANOVA for both salt stress-sensitive and resistant varieties indicated that salt treatment represented the main source of variability in all studied traits. Salt treatment significantly reduced root and shoot dry weight (RDW and SDW), relative water content (RWC), and chlorophyll content (Chl a, Chl b, and Chl T). However, increases in electrolyte leakage (EL) along with proline and total soluble sugar (TSS) contents were recorded. In addition, large variations in all measured traits were found between varieties. The 'Massine' and 'Laanaceur' varieties displayed relatively higher RDW and SDW values. The 'Amira' and 'Adrar' varieties showed lower RWC values and Chl contents than those of the controls indicating their relative sensitivity to salt stress. Principal component analysis revealed that most of the variation was captured by PC1 (72% of the total variance) which grouped samples into three categories according to salt treatment. Correlation analyses highlighted significant associations between most parameters. Positive relationships were found between RDW, SDW, RWC, Chl content, and soluble proteins contents, while all of these parameters were negatively associated with EL intensity, proline content, and TSS content. The results from this study showed that the 'Massine' and 'Laanaceur' varieties were relatively salt-tolerant. These two salt-tolerant varieties present a good genetic background for breeding of barley varieties showing high salt tolerance.

pH 진동계 안에서 pH 감응성 자기진동 IPN 하이드로젤의 합성과 분석 (Synthesis and Characterization of pH-sensitive and Self-oscillating IPN Hydrogel in a pH Oscillator)

  • Wang, Liping;Ren, Jie;Zhang, Xiaoyan;Yang, Xiaoci;Yang, Wu
    • 폴리머
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    • 제39권3호
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    • pp.359-364
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    • 2015
  • A self-oscillating interpenetrating polymer network (IPN) poly(acrylic acid)/poly(ethylene glycol) (PAA/PEG) hydrogel was prepared by using radical polymerization with a two-step method. The IPN hydrogel was characterized by FTIR spectroscopy and morphological analysis. The results indicated that the chains of PEG and PAA twined to form porous structure which is beneficial to water molecules entering inside of the hydrogel. In addition, the pH-responsive behavior, salt sensitivity, swelling/de-swelling oscillatory behaviors and self-oscillation in a closed pH oscillator were also studied. The results showed that the prepared hydrogel exhibited pH-sensitivity, good swelling/de-swelling reversibility and excellent salt sensitivity. The self-oscillating behavior of swelling/de-swelling for the prepared hydrogel was caused by pH alteration coupled with the external media. This study may create a new possibility as biomaterial including new self-walking actuators and other related devices.

Influence of Corrosion Potential and Current Density on Polarization Curve Variations using Polycarbonate[III]

  • Park, Chil-Nam;Yang, Hyo-Kyung;Kim, Sun-Kyu;Kim, Myung-Sun;Cheong, Kyung-Hoon
    • Environmental Sciences Bulletin of The Korean Environmental Sciences Society
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    • 제4권1호
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    • pp.43-50
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    • 2000
  • In this study, experiments were carried out to measure the variations in the corrosion potential and current density of polarization curves using polycarbonate. The results were particularly examined to identify the influences affecting the corrosion potential including various conditions such as temperature, pH, catalytic enzyme, and salt. The lines representing the active anodic dissolution were only slightly shifted in the potential direction by temperature, pH, enzyme, and salt. The tafel slope for the anodic dissolution was determined based on the polarization effect with various conditions. The slope of the polarization curves describing the active-to-passive transition region were noticeably shifted in direction. Also, from the variation in the conditions, the optimum conditions were established for the most rapid transformation, including temperature, pH, corrosion rate, and resistance of corrosion potential. The second anodic current density peak and maximum passive current density were designated as the critical corrosion sensitivity(Ir/If). The value of Ir/If was then used in measuring the extent of the critical corrosion sensitivity of the polycarbonate. The potentiodynamic parameters of the corrosion were obtained using a Tafel plot.

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