• Title/Summary/Keyword: salt analysis

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Development of EST-SSR markers for genetic diversity analysis in little millet (Panicum sumatrense) genetic resources

  • Lee, Myung-Chul;Choi, Yu-Mi;Lee, Sukyeung;Yoon, Hyemyeong;Oh, Sejong
    • Proceedings of the Plant Resources Society of Korea Conference
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    • 2018.10a
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    • pp.74-74
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    • 2018
  • Little millet (Panicum sumatrense) is well known for its salt and drought stress tolerance and high nutritional value, but very limited knowledge of genetic variation and genomic information is available. This study was to develop highly polymorphic EST-SSR markers based on cross-species transferability of derived SSRs from switchgrass EST databases and characterize newly developed EST - SSRs to better understand the genetic diversity of collected 37 germplasm accessions of little millet. A total of 779 primer pairs were designed from the 22,961 EST sequences of switchgrass (Pancium virgatum), of which 48 EST - SSR markers were developed based on the trials of transferability of these primers in little millet. The EST - SSR amplicons showed reproducible single band polymorphism and produced a total of 160 alleles with an average of 3.3 alleles per locus in 37 accessions of little millet. T he average values of expected and observed heterozygosities were 0.266 and 0.123, respectively. T he polymorphic information content (PIC) values were observed in range of 0.026 to 0.549 with an average of 0.240. The genetic relatedness among the little millet accessions was evaluated by neighbor-joining dendrogram, which grouped all accessions into two distinct groups. The validation thus demonstrated the utility of the switchgrass EST - SSR markers in assessing genomic relationships in little millet. T he findings from this study could be useful for designing strategies for the identification of diverse germplasm for conservation and future molecular breeding programs for little millet.

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Modification of polyamide reverse osmosis membranes seeking for better resistance to oxidizing agents

  • Silva, Lucinda F.;Michel, Ricardo C.;Borges, Cristiano P.
    • Membrane and Water Treatment
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    • v.3 no.3
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    • pp.169-179
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    • 2012
  • One of the major limitations in the use of commercial aromatic polyamide thin film composite (TFC) reverse osmosis (RO) membranes is to maintain high performance over a long period of operation, due to the sensitivity of polyamide (PA) skin layer to oxidizing agents, such as chlorine, even at very low concentrations in feed water. This article reports surface modification of a commercial TFC RO membrane (BW30-Dow Filmtec) by covering it with a thin film of poly(vinyl alcohol) (PVA) crosslinked with glutaraldehyde (GA) to improve its resistance to chlorine. Crosslinking reaction was carried out at 25 and $40^{\circ}C$ by using PVA 1.0 wt.% solutions at different GA/PVA mass ratio, namely 0.0022, 0.0043 and 0.013. Water swelling measurements indicated a maximum crosslinking density for PVA films prepared at $40^{\circ}C$ and GA/PVA 0.0043. ATR-FTIR and TGA analysis confirmed the reaction between GA and PVA. SEM images of the original and modified membranes were used to evaluate the surface coating. Chlorine resistance of original and modified membranes was evaluated by exposing it to an oxidant solution (NaClO 300 mg/L, NaCl 2,000 mg/L, pH 9.5) and measuring water permeability and salt rejection during more than 100 h period. The surface modification effectively was demonstrated by increasing the chlorine resistance of PA commercial membrane from 1,000 ppm.h to more than 15.000 ppm.h.

Nonstoichiometric Studies of the Mixed Valency $La_{1-x}Ca_xFeO_{3-y}$ (혼합원자가 $La_{1-x}Ca_xFeO_{3-y}$의 비화학양론에 관한 연구)

  • Chul Hyun Yo;Woong Bum Pyun;Eun Seok Lee;Sung Joo Lee
    • Journal of the Korean Chemical Society
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    • v.32 no.1
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    • pp.9-14
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    • 1988
  • Perovskite type compounds of the $La_{1-x}Ca_xFeO_{3-y}$ system were prepared from stoichiometric mixtures of La_2O_3,\;CaCO_3$, and Fe(NO-3)_3{\cdot}9H_2O$ by heating at 1100$^{\circ}C$ for 24 hours. The crystallographic structures of the solid solutions of all compositions were orthorhombic systems. X-ray diffraction and Mohr salt analysis revealed that at higher y value the phase transition due to vacancy ordering occured and that the lattice volume decreased when the x value was increased. The value of nonstoichiometric ratio y were found to be in the range of $0.0{\sim}0.5$. Electrical conductivities of this systems are measured in temperature range of -100 to 100$^{\circ}C$. Ionic contribution to total conductivity was found from activation energy in the phase containing the open pathway due to vacancy ordering.

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Kinetics and Mechanism of the Hydrolysis of Diazidophenylmethane Derivatives (Diazidophenylmethane 유도체들의 가수분해반응 메카니즘에 대한 반응속도론적 연구)

  • Kwon, Ki Sung;Seo, Jee Hyung;Lee, Yong Gu
    • Journal of the Korean Chemical Society
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    • v.41 no.6
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    • pp.313-319
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    • 1997
  • Diazidophenylmethane derivatives(X: p-H, $p-OCH_3,\;p-F,\;p-CH_3$) were synthesized and the rate constants of hydrolysis of diazidophenylmethane derivatives were determined by UV spectrophotometry in 50:50(v/v) aqueous methanol at 25$^{\circ}C$. On the basis of rate equation, substituent effect, activation parameters, solvent effect, salt effect, and product analysis, it may be concluded that the hydrolysis of diazidophenylmethane derivatives proceed through $S_N2_CA$ mechanism below pH 2.0, while above pH 12.0 through $S_N2$ mechanism, and in the range of pH from 2 to 12 through $S_N1$ mechanism respectively.

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Status of Recognition, Effort, and Satisfaction of Customers on Low-Sodium Diet in Industry Foodservice (산업체 급식 피급식자들의 저나트륨식 인식 및 실천현황과 만족도)

  • Yoon, Sang Jin;Kang, Kun Og
    • Journal of the East Asian Society of Dietary Life
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    • v.27 no.2
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    • pp.168-175
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    • 2017
  • This study surveyed the status of recognition, effort, and satisfaction of customers on a low-sodium diet in industry foodservice. For recognition related to sodium intake, 34.6% answered 'sure' for awareness of WHO's recommended daily sodium intake. Recognition of healthiness of low-sodium diet scored an average of $3.77{\pm}0.8$. The most frequent dietary effort related to low-sodium diet was 'I leave the broth of soup/stew (23.7%)', and the most common reason for not making an effort related to low-sodium diet was 'I often eat out (25.2%)'. Recognition of saltiness of foodservice meals was $2.84{\pm}0.69$, and the saltiest food was 'kimchi (30.4%)', followed by 'side dish (17.9%)', 'soup/stew (16.8%)', and 'sauce (8.3%)'. Satisfaction of low-sodium foodservice meal was $3.04{\pm}0.71$. Reasons for recognition of saltiness of foodservice meal were mostly 'appropriate' or 'prefer less salty (86%)'. In the analysis of satisfaction of low-sodium foodservice meal according to occupation, satisfaction of 'level of saltiness ($F=5.046^{**}$)' scored an average of $3.18{\pm}0.72$, with the highest satisfaction from 'professionals'. Satisfaction of 'dietary behaviors related to sodium ($F=3.534^{**}$)' scored an average of $3.95{\pm}0.59$, with the highest satisfaction from 'government employees (p<0.01)'. These study results show that despite recognition of the healthiness of a low-sodium diet, efforts toward practicing the diet were less than adequate. Further, 25% felt that foodservice meal was a blend, whereas satisfaction of low-sodium diet was only 19%. Therefore, continuous education and advertisements are necessary in order to raise awareness as well as developing more concrete methods during preparation of meals, such as using a salt meter.

Study on Atmospheric Corrosion for Two Different Marine Environments in India

  • Saha, Jayanta Kumar
    • Corrosion Science and Technology
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    • v.6 no.3
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    • pp.120-127
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    • 2007
  • In any developing nation major investment goes for infrastructure and it is not exception in India. Good numbers of buildings, bridges, shopping malls, car parks etc. are coming up with steel for sustainable development. Thus protecting the structures from corrosion are the challenges faced by professionals for all types of steel structures. About 3% of GDP is accounted for loss due to corrosion. To combat this up to date corrosion map is called for as the country has wide variation of climatic zones with vastcoastline. Logically organic paint system can be prescribed based on the corrosion rate on bare steel with respect to environment. Present paper will emphasis on the study conducted on two types of structural steel coated with organic paint located in twomarine environment having been exposed for three years, Test coupons made from steels both bare and coated are deployed at two field stations having marine (Digha) and industrial marine (Channai) environments. Various tests like AC impedance DC corrosion, polarisation, salt spray test, $SO_2$ chamber and Raman spectroscopy were carried out both in laboratory on fresh as well as coupons collected from exposure sites. Rust formed on the bare and scribed coated coupons are investigated. It is found that normal marine environment at Digha exhibits higher corrosion rate than polluted marine environment in Channai. Rust analysis indicates formation of ${\propto}$-FeoOH protects or reduces corrosion rate at Channai and formation of non-protective ${\gamma}$-FeoOH increases corrosion rate at Digha. The slower corrosion rate in Channai than at Digha is attributed due to availability of $SO_2$, in the environment, which converts non‐protective rust ${\gamma}$-FeoOH to protective rust ${\propto}$-FeoOH. While comparing the damage on the coated panels it is found that low alloy structural steel provides less damage than plain carbon steel. From the experimentations a suitable paint system specification is drawn for identical environments for low medium and high durability.

Preparation of Porous Glass-Ceramics by the Sintering (소결법에 의한 다공질 결정화유리의 제조)

  • 박용완;이준영
    • Journal of the Korean Ceramic Society
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    • v.31 no.10
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    • pp.1218-1230
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    • 1994
  • In manufacturing process of porous glass-ceramics by the filler method, the sintering behaviour of crystallizable glass powder mixed with various salts was studied and also the effects of precipitated crystal phases on the properties of porous glass-ceramics were investigated. Fine-grained crystallizable glass powder was homogeneously mixed with various slat having grain size 100~200 ${\mu}{\textrm}{m}$ and sintered for densification. After washing out the inorganic salt with distilled water, the porous sintered body was heat treated additionly for crystallization. The MgO-Al2O3-SiO2 base glass was used as crystallizable glass powder and the water soluble salts such as K2SO4 and MgSO4 were used as filler. When K2SO4 was used, leucite crystal phase was formed as a result of the ion exchange and porous glass-ceramics which exhibit high temperature resistance and high thermal expansion coefficient of 17$\times$10-6/$^{\circ}C$ could be obtained. On the contrary, when MgSO4 was used, only slight ion exchange is observed and $\mu$-cordierite and $\alpha$-cordierite crystal phases were formed and porous glass-ceramics which exhibit low thermal expansion coefficient schedule were determined with the results of DTA curves, thermal shrinkage curves and XRD patterns analysis. From DTA curves and thermal shrinkage curves, it was found that the sintering densification have been completed at the temperature range of exothermic peak for crystallization. The pore size distributions and pore diameters were measured by mercury porosimeter. The pore diameter of porous glass-ceramics was 10~15 ${\mu}{\textrm}{m}$ when 100~200${\mu}{\textrm}{m}$ grain size of K2SO4 was used and it was 25~30 ${\mu}{\textrm}{m}$ when the same grain size of MgSO4 was used. The porous glass-ceramics K2SO4 used shows bimodal pore size distribution and its porous skeleton structure was ascertained by SEM observation.

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Preparation of Highly Tough Ethylene Vinyl Acetate (EVA) Heterogeneous Cation Exchange Membranes and Their Properties of Desalination

  • Kim, In Sik;Ko, Dae Young;Canlier, Ali;Hwang, Taek Sung
    • Korean Chemical Engineering Research
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    • v.56 no.3
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    • pp.361-369
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    • 2018
  • A manufacturing method has been devised to prepare novel heterogeneous cation exchange membranes by mixing ethylene vinyl acetate (EVA) copolymers with a commercial cation exchange resin. Optimum material characteristics, mixture ratios and manufacturing conditions have been worked out for achieving favorable membrane performance. Ion exchange capacity, electrical resistance, water uptake, swelling ratio and tensile strength properties were measured. SEM analysis was used to monitor morphology. Effects of vinyl acetate (VA) content, melt index (MI) and ion exchange resin content on properties of heterogeneous cation exchange membranes have been discussed. An application test was carried out by mounting a selected membrane in a membrane capacitive deionization (MCDI) system to investigate its desalination capability. 0.92 meq/g of ion exchange capacity, $8.7{\Omega}.cm^2$ of electrical resistance, $40kgf/cm^2$ of tensile strength, 19% of swelling ratio, 42% of water uptake, and 56.4% salt removal rate were achieved at best. VA content plays a leading role on the extent of physical properties and performance; however, MI is important for having uniform distribution of resin grains and achieving better ionic conductivity. Overall, manufacturing cost has been suppressed to 5-10% of that of homogeneous ion exchange membranes.

A Study of Upgrading Real Biogas via CO2 Precipitation Route Under Indian Scenario

  • Gehlaut, Avneesh Kumar;Gaur, Ankur;Hasan, Shabih Ul;Park, Jin-Won
    • Korean Chemical Engineering Research
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    • v.56 no.3
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    • pp.381-387
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    • 2018
  • Our study focuses on upgrading real biogas obtained under Indian scenario using carbon capture and utilization (CCU) technology to remove carbon dioxide ($CO_2$) and utilize it by forming metal carbonate. Amines such as monoethanolamine (MEA), diethanolamine (DEA), and sodium hydroxide (NaOH) were used to rapidly convert gaseous $CO_2$ to aqueous $CO_2$, and $BaCl_2$ was used as an additive to react with the aqueous $CO_2$ and rapidly precipitating the aqueous $CO_2$. All experiments were conducted at $25^{\circ}C$ and 1 atm. We analyzed the characteristics of the $BaCO_3$ precipitates using X-ray diffractometry (XRD), scanning electron microscopy - Energy dispersive spectroscopy (SEM-EDS) and Fourier-transform infrared spectroscopy (FT-IR) analyses. The precipitates exhibited witherite morphology confirmed by the XRD results, and FT-IR confirmed that the metal salt formed was $BaCO_3$, and EDS showed that there were no traces of impurities present in it. The quantity of the $BaCO_3$ was larger when formed with DEA. Also, a comparison was done with a previous study of ours conducted in Korean conditions. Finally, we observed that the carbonate obtained using real biogas showed similar properties to carbonates available in the market. An economic analysis was done to show the cost effectiveness of the method employed by us.

Quality Characteristics of Modified Doenjang and Traditional Doenjang (개량된장과 전통된장의 품질 특성)

  • Jeon, Hyeonjin;Lee, Sanghoon;Kim, Sangsook;Kim, Yoonsook
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.45 no.7
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    • pp.1001-1009
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    • 2016
  • This study was conducted to investigate the relationship between quality factors and palatability of modified Doenjang and traditional Doenjang. Fourteen types of Doenjang, including three modified Doenjang and 11 traditional Doenjang samples, were analyzed to evaluate their physicochemical and sensorial properties. There were differences in e-tongue, which indicates overall acceptability. Water contents, minerals, total sugar contents, salt contents, pH, titratable acidity, and free amino acids of Doenjang did not show significant differences. From the correlation and regression analysis, palatability was closely related to the e-tongue sensor such as $X_1$ (sourness), $X_3$ (saltiness), and $X_4$ (umami) to -0.772, -0.642, and 0.678, respectively. The regression equation for sensorial palatability (Y) was Y=$45.356-0.008X_1-0.010X_3$ with a coefficient of 0.882.