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Allergies are generally triggered by food, medication, physical exercise, stress, alcohol consumption, and dehydration. There are reports that indicate dehydration affects various kinds of physical allergies. Howev-er, there are few studies that have focused on the effects of dehydra-tion on asthma and allergy anaphylaxis. Therefore, we analyzed the ef-fects of dehydration on several kinds of allergy responses and exer-cise-induced asthma especially during the endurance exercise. PubMed was searched from April to July of 2019 using predefined search terms “dehydration,” “exercise,” and “allergy responses.” Based on the reference search, more than one-hundred articles were identified but eighteen papers met the inclusion criteria and were ana-lyzed for connections among exercise and dehydration, dehydration and exercise-induced asthma, and allergy responses in the main text. Results suggest that dehydration directly impairs stroke volume, cardi-ac output, and skin blood flow. This results in larger increases in core temperature, heart rate, and stroke volume. Additionally, exercise-in-duced dehydration reduces airway surface hydration, which results in an amplified brocnchoconstriction. This response to exercise occurs in those who suffer from exercise-induced asthma. Moreover, damage to the gut and impaired gut function relates to increased intestinal perme-ability after endurance exercise. Endurance exercise changes the im-munological profiles to activate antibody-mediated immunity. Also, nu-merous mast cells and eosinophils were recruited, therefore isotype switching to IgE antibodies occur, this hypersensitivity activates mast cell degranulation. After degranulation, proteases, leukotrienes, prosta-glandins, and histamine lead to many kinds of allergy symptoms.

Diospyros mespiliformis is a highly valued and threatened tree species within the Sahelo-Sudanian zone of Africa, but its seed germination requirements under cultivation are not well researched. In a first experiment which aimed at determining germination response of seeds to dehydration, fresh seeds were dried at room temperature for 26 days during which their moisture content, their germinability, and their viability were monitored at two-day intervals. In the second experiment, 14 pre-germination treatments were tested for their effect on the germination of dried seeds. Results showed that fresh seeds had 52.7% moisture and achieved 97.7% germination. As seeds were dried, percentage germination gradually decreased with decreasing moisture content and reached 0% when moisture content had dropped to 18%. Meanwhile, seed viability remained at 100% over drying duration. Seeds that were not germinated after air dry also recorded 100% viability. The most effective treatment for inducing germination of dried seeds was scarification using 98% sulfuric acid for 30 min which resulted in 96.6% germination. This study reports for the first time in D. mespiliformis seeds a desiccation-induced dormancy which can be efficiently alleviated by acid scarification. This study provides useful information that will contribute to efficient management of D. mespiliformis seed resources for propagation.

마그네슘 용융염전해의 원료물질로 무수염화마그네슘이 일반적으로 사용된다. 그러나 함수염화마그네슘으로부터 무수염화마그네슘을 제조하기 위한 탈수과정은 가수분해가 동반되어 마그네슘 산화물들이 생성되므로, 공기 중에서 탈수를 통한 무수염화마그네슘 제조는 어렵다. 본 연구에서는 공기중에서와 염화수소 분위기 하에서 탈수 온도(200~600oC)에 따른 탈수특성을 비교하였다. 공기중에서는 탈수온도가 증가함에 따라 MgOHCl과 MgO가 생성되었지만, 염화수소 분위기하에서는 300oC 이상에서 무수염화마그네슘이 생성되었다. 염화수소 분위기에서 무수염화마그네슘은 약 300oC에서 생성되기 시작하여 500oC에서 결정화가 완전히 이루어 지는 것을 확인하였다. 탈수실험에 사용된 염화수소는 모두 물에 용해시켜 염산으로 회수되었으며, 수용액 온도 20oC에서 최대 41%의 염산을 회수할 수 있었다.

Anhydrous magnesium chloride, dehydration product from magnesium chloride hydrate is a general raw material to prepare electrolytic magnesium. However, the dehydration is not trivial and can be accompanied by hydrolysis leading to the production of undesirable hydroxy chloride compounds of magnesium. Therefore, dehydration process is actually the most complicated and hardest in the electrolysis methods for the production of magnesium. In this work, the influence of dehydrating temperature has been studied at the temperature range from 200oC to 600oC in air and HCl gas atmosphere individually to compare the results. With increasing of dehydration temperature MgOHCl and MgO were obtained in air. On the other hand, when the temperature was increased above 300oC anhydrous magnesium chlorides were prepared in HCl gas atmosphere. Anhydrous magnesium chloride was formed at near 300oC and completely crystallized at about 500oC. All of the HCl used as atmosphere gas in the dehydration was recovered as hydrochloric acid solution at a water vessel up to 41% by weight at 20oC.

Background: Dehisced ginseng seeds need to be stored at cold temperatures for around 3 months to break their physiological dormancy, and thus, to aid in gemination. In the presence of high moisture in such an environment, seed spoilage and pre-germination may lower seed quality and productivity. To improve seed quality during cold-stratification, the effects of seed dehydration and temperature were tested. Methods and Results: In early December, dehisced ginseng seeds were dehydrated at 4 different levels and stored at 2℃ -2℃, and ?20℃ for 3 months. Germination was carried out on the filter papers moistened with distilled water; emergence of root, shoot, and seed spoilage were assessed. Seed viability was examined by the tetrazolium test. More than 90% of the seeds stored at 2℃ and ?2 ℃ without drying or endocarp dehydration germinated, but seeds that were dehydrated to have a moisture content (MC) below 31% showed poor germination and lost their viability. In addition, the seeds stored at ?20℃ failed to show effective germination. Conclusions: Seed storage after endocarp dehydration might help to improve seed quality and increase seedling's ability to stand during the spring-sowing of ginseng.

본 연구는 불순물을 포함하는 인산부생석고로부터 정제석고를 얻을 목적으로 수행되었다. 인산부생석고를 일정조건에서 탈수하고 수화시켜 석고성분만을 선택적으로 미립화 시킨 다음 325mesh로 습식사분하여 사하산물로 정제석고를 얻었다. 이 과정에서 석고의 회수율에 미치는 탈수온도, 탈수시간, 탈수율, aging시간, 수화농도, 수화온도, 초음파조사시간, 첨가제 등의 영향을 조사하였다. 실험결과, 인산부생석고를 140oC에서 6시간 동안 건조하여 완전히 무수석고 상태가 되도록 탈수 한 다음, 슬러리 농도 3~10%, 20~30oC의 수화온도, 수화시간 2시간의 조건에서 수화하여 사분하면 석고회수율이 95% 이상이 됨을 알았다. 회수된 석고의 품위는 회수율이 높을수록 높아지는 경향을 보였으며 회수율이 90% 이상 일 때 품위는 94~96%를 보였다. 이 밖에도 석고회수율을 높이기 위해서는 탈수된 석고가 공기와 접촉하는 시간이 16시간을 넘어서는 아니 되며, 구연산나트륨을 0.005M 정도 첨가하는 것과, 수화반응 초기에 5~10분 동안 초음파를 조사하는 것이 매우 유용한 수단임을 알았다.

This study was carried out for the purpose of recovering the refined gypsum from waste phosphogypsum. The refined gypsum was recovered as a under product of 325 mesh wet screening followed by dehydration and hydration stage. The influence of dehydration temperature and time, dehydration rate, aging time, slurry density of hydration and sonication time on the yield and grade of gypsum were investigated. The refined gypsum of 94~96% grade is recovered in 95% yield by wet screening after selective dehydration and hydration process, from the phosphogypsum. For the better separation efficiency of gypsum, it is recommended to treat the phosphogypsum at the conditions of as follows; 6hr's dehydration at 140oC, hydration slurry density of 3~10%, hydration temperature of 20~30oC, hydration time of 2hr. In additions, addition of sodium citrate 0.005M and sonication of 5~10 min. are effective for increase the recovery of gypsum. On the other hand, aging the dehydrated gypsum 16 hours or longer make decrease the recovery of gypsum remarkably.

Purpose: The aim of this study was to explore the prevalence of major chronic diseases related to daily oral water intake and to iden- tify the physiological parameters related to dehydration in Korean elderly. Methods: The data were collected from the sixth Korea Health and Nutrition Examination Survey (KHANES), which was a nationwide and cross-sectional survey in 2015. We analyzed 1,392 participants using t-test and logistic regression. All participants were divided into the adequate water intake (AWI) group and the non-adequate water intake (NAWI) group based on the dietary reference intakes for Koreans. Results: There was a significant differ- ence in the water intake between the AWI (6.8 cups in a day) and NAWI (2.8 cups) groups (p < .001). There was no statistically signifi- cant association between the level of water intake and any of the major chronic diseases. Blood urea nitrogen (BUN) and BUN/Creati- nine (Cr) ratio were significantly higher in the NAWI group. Especially, BUN/Cr ratio shows that the NAWI group reached dehydration status. Older age (adjusted odd ratio, OR = 1.07, 95% confidence interval, CI [1.04-1.10]), female gender (adjusted OR = 1.56, 95% CI [1.05-2.33]), lower body mass index (BMI) (adjusted OR = 1.00, 95% CI [0.92-1.00]), higher BUN (adjusted OR = 1.04, 95% CI [1.01- 1.08]), and higher urine specific gravity (USG) (adjusted OR = 1.56, 95% CI [1.19-2.05]) were factors associated with the NAWI group. Conclusion: The findings suggest that the level of water intake needs to be considered in relation to age, gender, BMI, BUN, and USG. These are sensitive physiological parameters used for predicting dehydration of the elderly according to their daily oral water intake. It would be helpful to develop strategies to prevent dehydration in elderly individuals and enhance their water intake.

Sliced and whole root of rehmannia were dehydrated in a laboratory dryer at 40, 60, 80, and 100℃ to evaluate the kinetic parameters for dehydration of rehmannia. The drying curves of both samples were characterized by a falling-rate drying period only. Sliced rehmannia dried 1.1 to 3.1 times faster than whole root of rehmannia depending on drying temperature. Equilibrium moisture content (EMC) of rehmannia samples at the drying temperature tested were 0.069-0.078 g water/g dry solid, which was coincided with the monolayer moisture content (0.06 and 0.07 g water/g dry solid) evaluated from desorption isotherms using GAB (Guggenheim-Anderson-de Boer) model. A logarithmic model for thin layer drying was applied to evaluate the drying time to reach EMC (tEMC) and drying constant (k). The effect of temperature on 1/tEMC and k was described by the Arrhenius model with activation energy values of 32.56 and 47.14 kJ/mol determined using the former parameter, and 34.27 and 38.26 kJ/mol determined using the latter parameter for sliced and whole root of rehmannia, respectively.

Sliced ginger samples were dried using 30, 50, and 80% maltodextrin, respectively, as a dehydrating agent. Themoisture content of the maltodextrin-treated ginger decreased with increasing concentrations of maltodextrin. The dehydratedginger was compared with hot air-dried and freeze-dried ginger samples in terms of rehydration ratio, gingerol content, color,and sensory characteristics. The rehydration ratio of the maltodextrin-treated ginger was superior to those of the hot-air driedor freeze-dried ginger. In addition, the maltodextrin-treated ginger had the highest content of 6-gingerol among the samples.Color as well as sensory scores for odor, texture, appearance, and overall acceptance were greater for the maltodextrin-treated ginger compared to the hot-air dried or freeze-dried ginger. These results indicate that drying ginger with maltodextrinis very efficient because good rehydration capacity is retained and minimal cell destruction can be achieved.

Optimum conditions for vacuum-drying ad cultivation of yeast cells for the production of active dry yeast were examined. At lower temperature, more drying time was required to dry the yeast pellet to reach the desirable water content(8%). Optimum temperature of vaccum oven and time for drying was 63℃and 90 min, respectively. Optimum medium composition for flask culture using cane molasses as the substrate were 0.25% sugar, 0.013% K2HPO4, 0.1% K2HPO4. and 0.125% (NH4)2SO4. Culture temperature 25℃ gave the highest survival rate of dired yeast. After finishing fed-batch culture and the culture was left in the fermentor without adding any sugar or nutrient, survival of the dried yeast harvested from the fermentor increased to 86.0% after 36 hr. It was also observed that the yeast cells with higher budding rates showed lower survival rate.

Bio-ethanol, which is one of the most studied renewable alternatives, can be obtained from the fermentation of sugar, starch, cellulose-based materials. Fermented beer from those raw materials contains 8～11 v/v % of ethanol and the beer is sent to distillation process so that 95～97 v/v % of hydrous ethanol can be produced. Although the ethanol from the distillation process is used for alcoholic beverage or industrial usage, its water content should be removed by an additional dehydration process such as azeotropic distillation or pressure swing adsorption process for using ethanol as blended fuel. In this study, an investigation was carried out on ethanol-water separation employing a PSA process with 3A zeolite as the adsorbent. The cycle of the PSA process was operated under the following variables: feed flow (80～100 L/h of 95 v/v% ethanol), adsorption temperature (110～140 ℃) and adsorption pressure (1.2 atm). PSA process including two molecular sieve dehydration columns filled with zeolites was installed at pilot plant scale for this study. The product purity through the dehydration columns reached minimum 99.5 v/v% and this PSA process could produce more than 1.0 kL of anhydrous ethanol on a daily basis.

본 논문에서는 우산의 물기를 건조하는 자동 제수 시스템을 제안한다. 우산의 물기 제거방법은 우산용 비닐을 씌우거나 사용자가 직접 우산을 털어 수동적으로 제거하는 번거로운 방법과, 수동으로 우산을 제수면에 접촉 시켜 물기 를 제거하는 제수기를 사용하는 방법이다. 기본 방법은 수동으로 제거해야 하는 번거로움 뿐만 아니라 제수기의 물기 제거 성능도 만족할 만한 건조감을 기대하기 힘든 문제점이 있었다. 이러한 문제점을 해결하기 위하여 에어 컴프레셔를 이용하여 사용자가 우산을 넣으면 압력 센서가 넣어진 우산의 무게를 감지해, 모터를 구동시키는 방식으로 우산의 물기 를 제거하는 시스템을 개발하였다. 본 발명품은 비닐을 사용하지 않아 폐비닐의 발생을 없앰으로써 경제적, 환경적인 효과를 얻을 수 있을 것으로 기대된다.

In this paper, an automatic dewatering system for drying water from umbrellas is proposed. In the past, there were problems that users had to put on plastic for removing the water from umbrella by covering it with a plastic or using a water dryer that removes water by manually touching the umbrella to the water surface. But this method was hard to expect. To solve these problems, an air compressor was used to develop a system to remove water from the umbrella by detecting the weight of the umbrella with pressure sensor when the user puts the umbrella into the dewatering machine and driving the motor. It is expected that this invention will have economic and environmental effects by eliminating the use of waste vinyl.

염화희토류 수화물(RECl3·xH2O) 내 존재하는 수분을 제거하기 위하여 탈수화 장치를 제작하여 8가지 (La, Ce, Nd, Pr, Sm. Eu, Gd, Y)Cl3·xH2O에 대한 탈수화 실험을 수행하였다. 탈수화 과정 중 희토류옥 시염화물의 형성을 억제하기 위하여 TGA 분석을 바탕으로 하여 단계적인 온도 상승(80→150→230℃)구 간을 설정하였으며 증발된 수분의 원활한 이동을 위하여 예열된 Ar 가스와 vacuum pump를 이용하였다. 각 온도구간에서의 탈수화 정도를 살펴본 결과 YCl3·xH2O를 제외한 염화희토류 수화물은 원자번호가 높을수록 높은 온도에서 더 많은 탈수화가 일어남을 알 수 있었다. 탈수화 과정 후 희토류옥시염화물의 형성은 보이지 않았으며 염화 희토류 수화물 내 수분을 10%이하로 감소시킬 수 있었다.

The dehydration schemes of rare earth (La, Ce, Nd, Pr, Sm. Eu, Gd, Y) chloride hydrates was investigated by using a dehydration apparatus. To prevent the formation of the rare earth oxychlorides, the operation temperature was changed step by step (80 150 230 ) based on the TGA (thermo-gravimetric analysis) results of the rare earth chloride hydrates. A vacuum pump and preheated Ar gas were used to effectively remove the evaporated moisture and maintain an inert condition in the dehydration apparatus. The dehydration temperature of the rare earth chloride hydrate was increased when the atomic number of the rare earth nuclide was increased. The content of the moisture in the rare earth chloride hydrate was decreased below 10% in the dehydration apparatus.

분자압축탈수 방법을 이용하여 기존의 다른 건조방법보다 우수한 탈수 및 건조된 생강을 얻고자 생강을 이용한 분자압축탈수법에 탈수제(maltodextrin) 첨가량, 탈수시간, 절단 두께를 다르게 한 후 반응표면분석법으로 최적화하여 생강의 탈수 및 건조 최적조건을 얻고자 하였다. 분자압축탈수 방법을 이용한 생강의 탈수제 첨가량을 증가시킬수록 탈수율, 복원율, 관능적 특성의 외관(external), 향기(flavor), 조직감(texture) 및 전체적인 기호도(overall acceptability) 등은 증가하였으나 색(color)의 경우 낮아졌다. 또한 탈수시간, 절단 표면을 증가시킬수록 탈수율, 복원율, 관능적 특성이 증가하는 경향을 나타내었다. 분자압축탈수를 이용한 생강의 최적조건 범위는 탈수제 첨가량이 70-82%, 탈수시간이 5.2-9.2시간 이고 절단 두께가 1.0-1.2 mm로 설정되었다. 따라서 분자압축탈수 방법을 이용한 생강의 최적 탈수 및 건조조건은 탈수제 첨가량이 76%, 탈수시간 7.2시간, 절단 두께 1.1 mm가 적당한 것으로 나타났다.

The purpose of this study was to determine the optimal mixing ratios for three different concentrations of maltodextrin, dehydration time, and cutting thickness to prepare gingers using molecular press dehydration (MPD) through response surface methodology (RSM) based on the dehydration rate, rehydration rate, and a sensory evaluation. As maltodextrin concentration increased, dehydration rate, rehydration rate, external, flavor, texture, overall acceptability of the gingers tended to be high, and the color tended to be low. As the dehydration time and cutting thickness increased, dehydration rate, rehydration rate and the sensory evaluation of the gingers tended to be high. The maltodextrin concentrations were 70-82%, dehydration time was 5.2-9.2 hr, and cutting thickness levels were 1.0-1.2 mm. The optimal mixing ratios, maltodextrin concentration, dehydration time, and cutting thickness for manufacturing the best quality of gingers using molecular press dehydration were 76%, 7.2 hr, and 1.1 mm, respectively.

대표적인 재료로서 바나나를 선정하여 건조방법과 조건에 따른 최적화에 사용할 수 있는 Ascorbic acid 저하속도와 비효소적 갈변속도에 대한 반응속도 예측 모델식을 결정하였다. Ascorbic acid 저하 속도와 비 효소적 갈변속도를 각각 1차반응, 0차반응으로, 두반응의 온도 의존성은 Arrhenius식으로 나타내어 SPSS Computer Program을 이용하여 실제 측정된 Ascorbic acid와 비효소적 갈변의 data에 가장 접근하도록 Parameter를 반복계산하여 찾았다. 얻어진 반응속도식에서의 Parameter값들은 R. SQUARE값이 평균 0.99이상이므로 살험치를 잘 예측하였으며 건조공정의 최적화에 이용될 수 있을 것으로 생각되어진다. Ascorbic acid 저하속도와 비효소적 갈변속도는 건조초기에 낮고 건조가 진행되어 수분함량의 감소와 함께 최대속도를 보이다가 서서히 감소하였다. 이때 동결건조의 경우가 가장 안정된 품질변화를 나타냈음을 알 수 있었다.

Kinetics of ascorbic acid and browning that may use on the optimization of food dehydration were evaluated. Banana was chosen for this as the representative test material. We have described the destruction of ascorbic acid and browning as first and zero order reactions. The temperature dependence between two reactions were conducted with Arrhenius equation. Finally we have operated SPSS computer programs reapeatedly that we found very dose value of the parameter between result of ascorbic acid and browning. The attained Kinetic models were well prepared for the value of result experiments and the models may use on optimization for dehydration progress. Destruction rate of ascorbic acid and browning rate were low at initiation of progress, increased to show maximum at the low moisture on mid-progress and then decreased gradually. Freeze drying showed the most constant quality of product in this case.

충격방법(衝擊方法)에 의(依)하여 고추씨를 분리(分離)할 수 있으나 그 수율(收率)을 45%이상(以上) 올릴 수는 없었다. 따라서 보다 높은 씨분리수율(分離收率)을 이룩하기 위하여 고추 조직(組織)에 대(對)한 가열효과(加熱效果)를 시도(試圖)한 결과(結果) 씨의 분리(分離)가 용이(容易)하게 이룩될 수 있는 고추 내(內)의 공격(空隔)이 증가(增加)되었다. 이와같은 가열효과(加熱效果)를 씨의 분리(分離)에 이용(利用)키 위하여 회전사식원통형(回轉篩式圓筒型) 씨분리기(機)에 65℃, 0.61m/sec의 열풍(熱風)을 송입(送入)하면서 씨를 분리(分離)할 경우 93%까지 분리수율(分離收率)을 높일수 있었다. 열풍하(熱風下)에서의 씨의 분리(分離)는 고추의 절단부위(切斷部位)에 따라 차이(差異)는 있었으나 고추 건조(乾燥)가 완료(完了)되기 이전(以前)에 씨의 분리(分離)를 완료(完了)할 수 있었으므로, 동시탈종(同時脫種) 건조방법(乾燥方法)이라는 새로운 고추의 가공방법(加功方法)을 개발(開發)하게 되었다.

Seed separation out of fresh red pepper by impact methods was effective but impossible to separate over 45% of seed. For the increase of seed separation, dehydration effect was studied with the slices of pepper. Heat deformation during the course of drying at hot air of 0. 61m/sec velocity at temperature of 65℃, increased the separation up to 93% with a halfcut pepper. Seed separation was remarkably different upon the location of cut, but it was completed prio tothe completion of drying in every cutting orientations. From these results a simultaneous seed separation and drying operation techniques is successfully developed.