• Title/Summary/Keyword: SALINITY

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Characteristics of food waste: water and salinity contents

  • Lee, Jae-Han;Kang, Yoon-Gu;Luyima, Deogratius;Park, Seong-Jin;Oh, Taek-Keun;Lee, Chang Hoon
    • Korean Journal of Agricultural Science
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    • v.47 no.2
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    • pp.375-380
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    • 2020
  • The high intrinsic water content and salinity of food waste prevent a smooth composting process and consequently cause social, economic and environmental problems. In this study, we investigated the distribution of the water content and salinity in food wastes to obtain useful primary data to ensure adequate and quality recycling. A total of 300 food waste (FW) samples were collected from residential apartments (home generated FW), a wide range of restaurants, i.e., restaurant generated FW that included Korean, Chinese, Japanese and western FWs, and several places that included food waste processing facilities (dehydrated FW cakes). The collected food wastes were oven dried for 48 hours at 80℃ after which the water and salinity contents were analyzed. The results show that the average water content of the FWs was 72.45 ± 10.51%, and the average salinity content was 2.03 ± 0.57%. Furthermore, the salinity of the collected FWs was characterized by where the FW was generated. By location, the salinity concentration of home generated FW was 2.30% while western food had the lowest salinity concentration of 1.18%. However, dehydrated cakes had the highest salinity concentration of 2.84%. Especially, the distribution of the salinity content in food wastes can form the basis for improving the compost quality in food waste recycling.

Analyses of Salinity Unit in the Secondary School Science Textbook and Suggestion for Its Correction (중등 과학교과서에서 사용된 염분 단위 분석 및 단위 개정을 위한 제안)

  • Park, Kyung-Ae;Choi, Ji-Young
    • Journal of the Korean earth science society
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    • v.30 no.4
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    • pp.513-526
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    • 2009
  • It has long been that the unit of oceanic salinity changed from permil (%o) to other unit. However, the middle-and high- school textbooks of science and earth science have still used %o as salinity unit that was defined a long time ago. The objectives of this study are to briefly discuss about the historical development of change in salinity unit and measurement techniques, to present differences between the salinity units of psu (practical salinity unit) and %o, and to address the need and validity for the correction of salinity unit in the textbooks. Twenty-seven kinds of textbooks based on the 7th National Curriculum were analyzed to investigate the expression of salinity unit and the definition of salinity. The results were compared with the usage of salinity units in the articles published in Journal of Korean Society of Oceanography from 1967 to 2008. The percentages by the use of %o were 96.3% in the text and 83.8% in the graphs or tables of the textbooks. By contrast, the scientific papers began to use psu from 1994 and then %o has seldom been used since 2004.

The Effect of Salinity on Biological Nutrient Removal in SBR (SBR공정에서 영양염류 제거에 대한 염분의 영향)

  • Song, Changsoo;Oh, Junseung
    • Journal of Korean Society on Water Environment
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    • v.18 no.3
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    • pp.237-243
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    • 2002
  • The effect of a salinity on the performance of a biological nutrient removal system was investigated using a model SBR(Sequencing Bach Reactor) system. The system was operated at a 12hr, 18hr, 24hr, and 36hr HRT with a salinity level of 20,000mg/L and compared with a system similarly operated with fresh water. The influent salinity level of 8,000 mg/L does not have a significant effect on BOD removal efficiency, there is a noticeable decrease in BOD removal rate from 10,000 mg Cl-/L. The Nitrogen could be removed from the saline wastewater with the same efficiency as for the fresh water because of low C/N ratio in anoxic period. The excess biological phosphorous removal is highly affected by the increase in the influent salinity. The efficiency is decreased from 96.6% to 43.4% when the influent salinity is increased from 0 to 20,000mg/L.

Experimental investigation of the influence of salinity gradient on low-concentration surfactant flooding in Berea sandstone

  • Ebaga-Ololo, Jestril;Chon, Bo Hyun
    • Journal of Industrial and Engineering Chemistry
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    • v.68
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    • pp.355-363
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    • 2018
  • There are serious issues with the application of surfactant flooding as a third recovery method, such as surfactant slug losses. In this study,the impact of the salinity gradient on the remobilization of oiltrapped in Berea sandstone was investigated by emphasizing the surfactant adsorption gradient and phase behavior to determine the optimal salinity of the chosen surfactant concentration for investigating the salinity gradient. Three salinity-gradient schemes were applied to six cores saturated with light and heavy oils. The positive salinity gradient provided the best recovery results with an in situ microemulsion formation that could be observed in the fluid collector.

Salinity Monitoring of Soups of The Institutions Enrolled at Center for Children's Foodservice Management (어린이급식관리지원센터 등록 시설 국물음식의 염도 모니터링)

  • Park, Hyun Nae;Kim, Soon Mi
    • Journal of the East Asian Society of Dietary Life
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    • v.26 no.6
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    • pp.507-516
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    • 2016
  • The salinity of soups of institutions enrolled at the Center for Children's Foodservice Management was monitored to reduce sodium intake of children by continuously managing salinity of soups provided by children food service. Monitoring of salinity was conducted by a salinity meter (SB-1500H, HM digital) three times in 2016 by patrolling children's institutions for the instruction of public health. The average salinity of soups provided by total children's institution showed a significant decrease in salinity - $1^{st}$ 0.45%, $2^{nd}$ 0.41% and $3^{rd}$ 0.39% - as monitoring was proceeded (p<0.01). When salinity of soups was analyzed according to the type of children's institution, the salinity of national and public institutions showed no significant decrease. In contrast, the salinity of private institutions decreased significantly (p<0.05). Depending on the enrollment of the food service, there was no significant difference in average salinity of soups between large food services, which have over 50 children, and small food services, which have less than 50 children. However, all food services showed a salinity decrease from the $1^{st}$ monitoring to the $3^{rd}$ monitoring. Salinity according to the type of soup showed that salinity of clear soup, miso soup, and stew except beef soup decreased from the $1^{st}$ monitoring to $3^{rd}$ monitoring. However, there was no significant difference in salinity according to the type of soup which can be attributed to a large difference in salinity among the same type of soup. The individual soup showing the biggest difference between maximum and minimum salinity of soup was egg soup (0.62%), potato soup (0.54%), and mushroom soup (0.64%). The present average salinity of soup provided by children's institutions was less than 0.5% which is the recommended standard of the Ministry of Food and Drug Safety. However, the salinity of soups should be managed within a certain range including the minimum salinity regarding the taste education of children.

Salinity Determination Using Temperature Compensated On-Line Refractometer (온도보상형 온라인 굴절계를 이용한 해수의 염도 측정)

  • 최한욱;김영한
    • Journal of Korean Port Research
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    • v.15 no.1
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    • pp.99-105
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    • 2001
  • An on-line refractrometer made of easily obtainable materials is built to determine the salinity and temperature of sea water, and its performance is examined by applying the refractometer to known salt solution. Since refractive index and temperature are measured simultaneously, it is possible to compensate the effect of temperature for accurate measurement. The outcome of salinity measurement for the different concentrations of salt solution indicates that the device is suitable for the salinity measurement by yielding stable and reproducible reading.

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The Study on the Salinity of Kimchi and Subjective Perception of Salinity in Pusan Area (부산지역의 김치 염도 및 김치 염도에 대한 인식도)

  • 문갑순;송영선;이치간;김성경;류복미;전영수
    • Korean journal of food and cookery science
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    • v.13 no.2
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    • pp.179-184
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    • 1997
  • To investigate the salinity of Kimchi and subjective perception of salinity on Kimchi in Pusan area, questionaire and sampling of Kimchis was performed twice during summer and winter, 1996 and 1997. Most of subjects attend in this survey were in their thirties and fourties, graduated from high school and their monthly income was in the range of one million to two million won. Above 90% of subjects live in Pusan and Kyung-nam area and most of them learned how to make Kimchi from their mother and believed that the salinity of home-made Kimchi is constant through the year. The survey on the subjective perception of salinity of summer Kimchi showed that salinity of Kimchi perceived as less salty was 2.46${\pm}$0.24% by housewives and 2.57${\pm}$0.23% by their family members, salinity of summer Kimchi perceived as appropriate was 2.61${\pm}$0.51% and 2.65${\pm}$0.57%, salinity of Kimchi perceived as salty was 2.77${\pm}$0.61% and 2.62${\pm}$0.47%, respectively. These data shows that salinity and subjective perception of salinity of summer Kimchi are correlated. The salinity of winter Kimchi perceived as less salty was 2.98${\pm}$0.83% by housewives and 3.02${\pm}$0.71% by this family members. The salinity of winter Kimchi perceived as appropriate was 2.82${\pm}$0.49% and 2.94${\pm}$0.53%, and the salinity of winter Kimchi perceived as salty was 3.20${\pm}$0.61% and 3.25${\pm}$0.49%, respectively. These data does not show salinity and subjective perception of salinity of winter Kimchi is correlated. Average salinity of summer Kimchi was 2.55${\pm}$0.44%, while average salinity of winter Kimchis was 2.97${\pm}$0.54%, which is for preservation during winter time. Furthermore, most of subjects believed that salinity of Kimchi may affects the occurrence of diseases, such as hypefention. 80% of subjects answered that it is better to eat Kimchi perceived as less salty. Therefore it is recommended to make Kimchi with below 3%o of salinity in factory scale in the near future.

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Salinity affects microbial community structure in saemangeum reclaimed land

  • Kim, Kiyoon;Samaddar, Sandipan;Ahmed, Shamim;Roy, Choudhury Aritra;Sa, Tongmin
    • Proceedings of the Korean Society of Crop Science Conference
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    • 2017.06a
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    • pp.364-364
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    • 2017
  • Saemangeum reclaimed land is a part of Saemangeum Development Project. Most of the persistent problems of Saemangeum reclaimed land remain to be related to soil salinity. Soil salinity is a major abiotic factor related to microbial community structure and also fungi have been reported to be more sensitive to salinity stress than bacteria. The aim of this study was conducted to investigate the effect of soil salinity levels on the microbial communities in Saemangeum reclaimed land using 454 pyrosequencing analysis. Soil samples was collected from 12 sites of in Saemangeum reclaimed land. For pyrosequencing, 27F/518R (bacteria) and ITS3/ITS4 (fungi) primers were used containing the Roche 454 pyrosequencing adaptor-key-linker (underlined) and unique barcodes (X). Pyrosequencing was performed by Chun's Lab (Seoul, Korea) using the standard shotgun sequencing reagents and a 454 GS FLX Titanium sequencing System (Roche, Inc.). In the soil samples, Proteobacteria (bacteria) and Ascomycota (fungi) shows the highest relative abundance in all the soil sample sites. Proteobacteria, Bacteroidetes, Plantomycetes, Gemmatimonadetes and Parcubacteria were shown to have significantly higher abundance in high salinity level soils than low salinity level soils, while Acidobacteria and Nitrospirae has significantly higher relative abundance in low salinity level soils. The abundance of fungal, Ascomycota has the highest relative abundance in soil samples, followed by Basidiomycota, Chlorophyta, Zygomycota and Chytridiomycota. Basidiomycota, Zygomycota, Glomeromycota and Cerozoa were show significantly higher relative abundance in low salinity level soils. The principal coordinate analysis (PCoA) and correlation analysis shown to salinity-related soil parameters such as ECe, Na+, SAR and EPS were affected to bacterial and fungal community structure. Proteobacteria, Bacteroidetes, Plantomycetes exhibited significantly positive correlation with soil salinity, while Acidobacteria exhibited significantly negative correlation. In the case of fungal community, Basidiomycota and Zygomycota were seen show significantly negative correlation with salinity related soil parameters. These results suggest that provide understanding effect of soil salinity on microbial community structure and correlation of microbial community with soil parameters in Saemangeum reclaimed land.

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Effects of Microalgae and Salinity on the Growth of Three Types of the Rotifer Brachionus plicatilis

  • Cabrera Tomas;Bae Jean Hee;Bai Sungchul C.;Hur Sung Bum
    • Fisheries and Aquatic Sciences
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    • v.8 no.2
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    • pp.70-75
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    • 2005
  • We investigated the effects of salinity and three food species of microalgae on the growth of three types of the rotifer Brachionus plicatilis, with the aim of improving mass culture of rotifers in hatcheries. Three types (large, small, and ultra-small) of the rotifer were cultured at 16 ppt and 32 ppt salinity with the green algae Chlorella ellipsoidea, Nannochloris oculata, or Tetraselmis tetrathele. The maximum density and specific growth rate were compared for each rotifer type. Ultra-small rotifers grew significantly faster at 16 ppt salinity than at 32 ppt, and C. ellipsoidea and T. tetrathele promoted significantly higher growth than did N. oculata. However, small rotifers grew significantly better at 32 ppt salinity than at 16 ppt, and small rotifers fed on N. oculata achieved the highest density at 1,185 individuals/ml. Large rotifers grew faster at 16 ppt salinity than at 32 ppt, with a diet of T. tetrathele resulting in the fastest growth. Each type of rotifer thrived under different regimens of microalgae and salinity.

Effect of salinity on growth and nutrient uptake of Ulva pertusa (Chlorophyta) from an eelgrass bed

  • Choi, Tae-Seob;Kang, Eun-Ju;Kim, Ju-Hyoung;Kim, Kwang-Young
    • ALGAE
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    • v.25 no.1
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    • pp.17-26
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    • 2010
  • The effects of salinity on various ecophysiological parameters of Ulva pertusa such as growth, nutrient uptake, photosynthetic performance and internal nutrient composition were tested. U. pertusa was collected from an eelgrass bed in a semi-protected embayment on the southwest coast of Korea. Under salinity regimes from 5 to 40 psu, the specific growth rates $(\mu)$ of U. pertusa ranged from 0.019 to $0.032\;d^{-1}$. Maximum growth rate was observed at 20 psu, and minimum at 40 psu. This species showed various uptake rates for nitrate and phosphate. Nutrient uptake was noticeably higher at intermediate salinity levels, and lower at both extremes. Salinity significantly influenced chlorophyll-$\alpha$ content and effective quantum yield. Tissue nitrogen content ranged from 1.5 to 2.9% N (dry weight), whereas tissue phosphorus ranged from 0.1 to 0.14% P (dry weight). The N : P ratio in the tissue of U. pertusa was considerably higher, ranging from 30 to 50. Increased growth at lower salinity suggests that the initial growth rate of U. pertusa is greater during the rainy season (i.e., late spring and early summer) than any other season during the year. The appearance of an Ulva bloom in eelgrass beds may be triggered by salinity more than by other environmental factors such as light and temperature.