• Korean Journal of Food Science and Technology
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• v.21 no.2
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• pp.307-312
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• 1989

Internal mass transfer during osmotic dehydration of carrots in sugar solutions was examined as a function of concentration, temperature and immersion time of those solutions using moisture loss, sugar gain, molality and rate parameter. Influence of osmotic dehydration and blanching on browning reaction of vacuum dried carrots(3% MC: wet basis) was also evaluated. Increasing the concentration and temperature of sugar solutions increased moisture loss, sugar gain, molality and rate parameter. Water loss and sugar gain were rapid in first 4 min and then levelled off. The rate of sugar gain and molality changes on temperature was significant in lower concentration$(20^{\circ}\;Brix)$ compared to higher concentration$(60^{\circ}\;Brix)$. The changes of rate parameter were affected by concentration than by temperature of sugar solutions. Moisture loss during osmotic dehydration using a sugar solution $(60^{\circ}\;Brix,\;80^{\circ}C)$ with 20min immersion time was 55.7%. Effect of osmotic dehydration and blanching before vacuum dried to 3% MC(Wet basis) on browning reaction was significant. Minimum browning reaction during vacuum drying was carried out using pretreatments such as osmotic dehydration in sugar solution$(40^{\circ}\;Brix,\;80^{\circ}C)$ with 16 min immersion time(O.D.=0.09) and blanching with 12 min immersion time at $80^{\circ}C$(O.D.=0.31) compared to control(O.D.=1.59).

• Food Science and Preservation
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• v.17 no.6
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• pp.763-769
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• 2010

We examined variations in ginger dehydration and recovery rate upon use of dextrose of different equivalence values. The dehydration rate varied with dextrose equivalent and the dehydration rate increased as the equivalence value increased. Both dehydration and recovery rates varied with dextrose molecular weight. Moisture content was lowest in samples prepared by freeze-drying, and neither dextrose equivalent nor molecular weight affected moisture level. Upon color analysis, ginger dried using dextrose varying in equivalence and molecular weight was similar in color to the original material, unlike ginger dried by other methods. Hot-air-dried ginger scored lowest in all sensory tests, compared with ginger prepared by molecular press dehydration using dextrose varying in equivalence and molecular weight. With respect to the appearance of ginger, freeze-dried samples were optimal, but molecular press dehydration yielded samples that scored best upon overall evaluation. When all quality evaluation items were taken together, molecular press dehydration resulted in a better quality product than the older hot-air or freeze-drying methods.

• Membrane Journal
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• v.13 no.4
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• pp.257-267
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• 2003

For the treatment of reactive phenolic resin waste, a simulation model of pervaporative dehydration process has been developed through hollow fiber membrane module. Some of basic parameters were determined directly from dehydration of the waste liquid through a flat sheet membrane to get realistic values. The simulation model was verified by comparing the simulated values with experimental data obtained from hollow fiber membrane module. Hollow fiber membranes with active layer coated on inside fiber were used, and feed flew through inside hollow fiber. Feed flow rate affected membrane performances and reaction by providing a corresponding temperature distribution of feed along with fiber length. Feed temperature is also a crucial factor to determine dehydration and reaction behavior by two competing ways; increasing temperature increases permeation rate as well as water formation rate. Once the permeate pressure is well below the saturated vapor pressure of feed, permeate pressure had a slightly negative effect on permeation performance by slightly reducing driving force. As the pressure approached the vapor pressure of feed, dehydration performances declined considerably due to the activity ratio of feed and permeate.

• Proceedings of the IEEK Conference
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• 2001.10a
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• pp.342-348
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• 2001

This study was conducted to obtain granular crystalline gypsum that can be used as raw material for plaster boards or cements from waste Plaster board. We could disintegrate preferentially gypsum to gypsum needle in 10${\mu}{\textrm}{m}$ or less size among the contents of waste plaster board (gypsum, paper, fiber, and inorganic material .etc.) by hydration afterwards the dehydration of crushed waste plaster board. In this case, the optimum conditions for minimizing the size of gypsum were dehydration rate of 75%~ 85%, hydration concentration of 10~20%, agitation speed of 250~400rpm, crushing size of 2cm or less. Gypsum of 98.21% grade was recovered with 99.0% yield from under screenings of 325mesh wet screening which followed by the dehydration-hydration process performed in the conditions of dehydration rate of 80%, hydration concentration of 15%, agitation speed of 300rpm, crushing size of 2cm or less. Subsequently, Plate-like Crystalline gypsum of is 151${\mu}{\textrm}{m}$ size and the grade of 99.49% with the Yield of 98.0% from the upper screenings of 270mesh wet screening carried out after the re-crystallization of the recovered gypsum needle slurry.

• Journal of Plant Biotechnology
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• v.45 no.4
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• pp.333-339
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• 2018

The mature zygotic embryos of the Hevea brasiliensis were cryopreserved through the use of the vitrification and encapsulation/dehydration techniques. In all the experiments, the zygotic embryos were pre-cultured for three days in the MS medium supplemented with 0.3 M sucrose before they were used for the cryopreservation technique. In the vitrification procedure, the effect of the plant vitrification solutions (PVS2 and PVS3) and exposure time were studied. The highest survival rate (88.87%) and regrowth (66.33%) were achieved when the precultured zygotic embryos were incubated in a loading solution for 20 minutes at $0^{\circ}C$. They were subsequently exposed to PVS2 for 120 minutes at $0^{\circ}C$ and plunged directly into liquid nitrogen. Cryopreservation by the encapsulation-dehydration method was successfully done by leaving the encapsulated zygotic embryos in a laminar flow for 4 hours prior to plunging into a LN. The survival rate and regrowth of the encapsulated zygotic embryos were 37.50% and 27.98%, respectively. The cryopreserved zygotic embryos were able to develop into whole plants.

• Journal of the Korean Ceramic Society
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• v.18 no.1
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• pp.35-40
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• 1981

The kinetics of the dehydration of Ha-dong kaolin was studied isothermally at various temperatures. Dehydration rate was measured by thermogravimetry method in the temperature range of 440~50$0^{\circ}C$ and the particle size range of 170~325mesh. The general equation f($\alpha$)=kt, where $\alpha$ is the fraction reacted in the time and the function f($\alpha$) depends on the reaction mechanism, was applied to this reaction. The function, f($\alpha$) was obtained by application of reduced-time plot and plot of lnln (1-$\alpha$) vs. ln (time), and expressed as (1-$\alpha$) ln (1-$\alpha$)+$\alpha$=kt. The dehydration followed the diffusion-controlled reaction model and gave activation energy of 30Kcal/mole.

• The Journal of Korean Medicine
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• v.44 no.4
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• pp.163-169
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• 2023

Methods: This study presents a comprehensive case study of an elderly male diagnosed with acute kidney injury (AKI) resulting from severe dehydration, supported by an extended follow-up with laboratory findings. Results: An 83-year-old male patient experienced severe diarrhea overnight, leading to hospitalization due to symptoms of dehydration and hypotension. His laboratory results displayed a typical AKI pattern, including a significant increase in creatinine levels (5.19 mg/dL) and the presence of hyperkalemia and hyponatremia. Following general treatments, including the administration of an herbal drug (Bulhwangeumjeonggi-san), the estimated glomerular filtration rate (eGFR) improved from 10 ml/min (Stage 5) to 34 ml/min (Stage 3) within five days when he was discharged. Although subsequent eGFR tests, conducted one and two months later as an outpatient, revealed an improvement of 42 ml/min, the patient still experienced mild chronic dysfunction as a consequence. Conclusion: This study presents a noteworthy case of acute kidney injury attributed to severe dehydration, emphasizing the importance of medical awareness regarding diarrhea-induced kidney function impairment, especially in the elderly population.

• Applied Biological Chemistry
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• v.41 no.5
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• pp.372-376
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• 1998

Internal mass transfer during osmotic dehydration of gingers in sugar solution was examined as a function of concentration, temperature and immersion time of those solutions using moisture loss, sugar gain, molality and rate parameter. Influence of osmotic dehydration on browning reaction and texture properties of air dried rehydrated was also evaluated. Increasing the concentration and temperature of sugar solutions increased moisture loss, sugar gain, molality and rate parameter. Water loss and sugar gain were rapid in the first 3 min and then changed gentle slope. Moisture loss during osmotic dehydration using a sugar solution $(60\;Brix,\;80^{\circ}C)$ with 18 min immersion time was 40.05 g moisture/100 g wet ginger which was 52% reduction of initial moisture content in ginger (83.02%, wet basis). The changes of rate parameter were more affected by temperature than by concentration of sugar solution. Minimum browning degree (O.D.=0.027) was carried out by osmotic dehydration in sugar solution $(40\;or\;50\;Brix,\;80^{\circ}C)$ with 15 min immersion time compared to control (O.D.=0.132). Influence of osmotic dehydration on puncture forces of 3 min rehydrated ginger in boiling water were $22{\sim}34%$ of reduction, while blanching treatment had not affected compared to those of control.

• Korean Journal of Animal Reproduction
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• v.14 no.1
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• pp.43-49
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• 1990

To improve the freezing techniques of animal embryos using vitrification solution as a cryoprotectant rabbit embryos, by cell stages, dehydration temperature and dehydration temperature and dehydratin time, were frozen-thawed and cultured. Following are the main results obtained. 1. The damage rate of zona pellucida after thawing was higher(13.6%) when the cell stage of embryos was less than 4 cells than when the cell stage was 8~16 cell or morula. The damage rate was higher when the dehydration temperature was 4$^{\circ}C$ than -3$0^{\circ}C$ or -50~-8$0^{\circ}C$. The zona pellucida was damaged more when dehydrated for 5 min than when dehydrated for 10~15 min. 2. After being cultured for 72 hours, 5.3% of 4 cell(or less) embryos were developed to morula, while 86.4% of morula embryos were developed further. 3. More percentage of embryos(73.2%) was developed when dehydrated at -3$0^{\circ}C$ than when dehydrated at 4$^{\circ}C$ at -5$0^{\circ}C$~-8$0^{\circ}C$. 4. The hatching rate was higher when dehydrated for 5 min. When the embryos were dehydrated for 10~15 min and cultured for 24 hours, they were not even developed or development was not good in later stages.

• Korean Journal of Food Science and Technology
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• v.47 no.6
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• pp.744-750
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• 2015

Purple sweet potatoes were dehydrated with maltodextrin with different dextrose equivalent (DE) values of 4-7, 13-17, 16.5-19.5, and 17-20. Maltodextrin was used as a molecular press dehydrating agent. The molecular dehydration rate of the purple sweet potatoes increased over time. As the DE of maltodextrin increased, the moisture content after 12 h of dehydration decreased from 65.7% to 40.8, 36.1, 34.9, and 28.6% for DE values of 4-7, 13-17, 16.5-17.5, and 17-20, respectively. Additionally, total phenolic content, anthocyanin, and 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activities decreased as the DE value of maltodextrin increased. While maltodextrins with DE values of 16.5-19.5 and 17-20 effectively dehydrated the purple sweet potatoes, total phenolic, anthocyanin, and DPPH radical scavenging activities were lowered during dehydration. The DPPH radical scavenging activities correlated to both the total phenolic content ($r^2=0.96$) and anthocyanin contents ($r^2=0.95$) of the purple sweet potatoes. These results indicate that the purple sweet potatoes were effectively dehydrated with maltodextrin whose DE values ranged 16.5-20, although there were losses in the total phenolic and anthocyanin contents.