• 상하수도학회지
• /
• 제14권1호
• /
• pp.117-126
• /
• 2000

Solubilization pretreatments were conducted to enhance the anaerobic digestion of the waste activated sludge. Four pretreatment techniques including heating, sonication freezing and thawing, and enzyme addition were employed to solubilize the waste activated sludge under various conditions. Thermal pretreatment by heating showed the highest efficiency compared with other methods, and freezing and thawing was confirmed as a feasible alternative of solubilization as well as the pretreatment of dewatering. There is a clear correlation between the solubilization efficiency of the waste activated sludge and the gas production. Batch digestion results showed the cumulative gas production as much as four times after thermal pretreatment as compared with that by the control sludge without pretreatment. As a result, hydrolysis or solubilization pretreatment might play a significant role in the high rate digestion of the waste activated sludge.

• 한방재활의학과학회지
• /
• 제21권4호
• /
• pp.191-203
• /
• 2011

Objectives: The purpose of this study is to investigate the clinical effects of heating-conduction therapy on lateral ligament injury induced by ankle sprain grade II. Methods: The 67 outpatients who were diagnosed as ankle sprain grade II were performed heating-conduction acupuncture therapy on lateral ligament injury. To evaluate the efficiency of heating-conduction acupuncture therapy, pain threshold with pressure algometer and visual analogue scale(VAS) were applied pretreatment and after 1st, 2nd treatment. Results: 1. The pain threshold and VAS score after 1st and 2nd treatment with an isolated injury of the anterior talofibular ligament showed statistically significant improvement compared with pretreatment. 2. The VAS score after 1st and 2nd treatment with an combined injury to the anterior talofibular and the calcaneofibular ligament showed statistically significant improvement compared with pretreatment. 3. The VAS score after 1st and 2nd treatment with an combined injury to the anterior talofibular, calcaneofibular and posterior talofibular ligament showed statistically significant improvement compared with pretreatment. 4. After 1st and 2nd treatment on the posterior talofibular ligament and after 2nd treatment on the anterior taofibular and calcaneofibular ligament with an combined injury to the anterior talofibular, calcaneofibular and posterior talofibular ligament the pain threshold showed statistically significant improvement compared with pretreatment. 5. Between isolated injury and combined injury of lateral ligament, the difference in pain threshold and VAS score was not statistically significant. Conclusions: Heating-conduction acupuncture therapy has clinical effects of pain reduction on patient with an isolated injury and combined injury of lateral ligament induced by ankle sprain grade II.

• 한국식생활문화학회지
• /
• 제15권2호
• /
• pp.95-100
• /
• 2000

This study was attempt to improve the quality of rapid- and low salt-fermented liquefaction of sardine (Sardinops melanoslicta). Effect of pretreatment methods such as water adding, heating, and intermittent NaCl adding on fermented liquefaction of chopped whole sardine were investigated. The divisions of the experimental samples by pretreatment methods were as follows; Sample A (water adding and heating): chopped whole sardine adding 20% water and then adding 3 and 5% NaCl consecutively at the intervals of 3 and 6 hrs during heating for 9 hrs at $50^{\circ}C$ and then fermented at $33^{\circ}C$ for 90 days. Sample B (preheating): chopped whole sardine with 8% NaCl and heating at $50^{\circ}C$ for 9 hrs and then fermented at $33^{\circ}C$ for 90 days. Sample C (control): neither pretreatment methods of water adding nor preheating on chopped whole sardine with 13% NaCl and then fermented at $33^{\circ}C$ for 90 days. Comparison of the appropriate fermentation period, yield of hydrolysate, chemical composition of fermented liquefied products were carried out. The highest content of amino nitrogen appeared at 60 days in the sample A, 75 days in the sample B, and 90 days in the sample C during the fermentation period. The appropriate fermentation period of the sample A was shorten 15 days than the sample B and 30 days than the sample C in the processing of sardine. The product A was lower NaCl (8.5%) and lower histamine content (25mg/100g) than the sample B and C. Possibly, three kinds of pretreatment methods such as water adding, heating, and intermittent NaCl adding, might be recommend as the processing of rapid- and low salt-fermented liquefaction product of chopped whole sardine.

• Carbon letters
• /
• 제17권1호
• /
• pp.1-10
• /
• 2016

Lignocellulosic biomass conversion to biofuels such as ethanol and other value-added bio-products including activated carbons has attracted much attention. The development of an efficient, cost-effective, and eco-friendly pretreatment process is a major challenge in lignocellulosic biomass to biofuel conversion. Although several modern pretreatment technologies have been introduced, few promising technologies have been reported. Microwave irradiation or microwave-assisted methods (physical and chemical) for pretreatment (disintegration) of biomass have been gaining popularity over the last few years owing to their high heating efficiency, lower energy requirements, and easy operation. Acid and alkali pretreatments assisted by microwave heating meanwhile have been widely used for different types of lignocellulosic biomass conversion. Additional advantages of microwave-based pretreatments include faster treatment time, selective processing, instantaneous control, and acceleration of the reaction rate. The present review provides insights into the current research and advantages of using microwave-assisted pretreatment technologies for the conversion of lignocellulosic biomass to fermentable sugars in the process of cellulosic ethanol production.

• Journal of the Korean Wood Science and Technology
• /
• 제40권5호
• /
• pp.343-351
• /
• 2012

A large diameter roundwood is an important element of Korean traditional buildings, Hanok, and is hard to be dried without surface cracks. Four different pretreatments, such as pre-cracking, oil heating, kerfing-oil heating and PEG impregnation, were investigated for reducing the surface cracks of large-diameter roundwood specimens during heat treatment. The roundwood specimens of pre-cracking, oil heating and kerfing-oil heating showed surface cracks during pretreatment, but that of PEG impregnation did not. It was confirmed that kerfing reduced the total crack width. Among the four pretreatments and control only the PEG impregnation roundwood specimen had no crack on both outer and inner surfaces after heat treatment. The PEG impregnation specimen shrank only 1.6% in the tangential direction while the pre-cracking did 8.0%.

• 한국식생활문화학회지
• /
• 제20권4호
• /
• pp.421-425
• /
• 2005

전처리 조건을 달리하여 얻은 추출물의 일반성분을 측정한 결과, 수분은 비열처리-효소 추출구보다 열처리-효소 추출구가 다소 높았으며, 조회분과 조펙틴은 유의적인 차이가 없었다. 상등액 추출율은 celluclast와 pectinex의 효소처리 했을때 무열처리-효소 추출구보다 열처리-효소 추출구가 다소 높게 나타났다. 젤리의 adhesiveness 값은 열처리-효소 추출구 일수록 그리고 Celluclast 효소만 처리했을 때 높게 나타났다. Celluclast 효소를 첨가하여 제조한 젤리에서만 값들이 증가하는 경향을 나타냈고 나머지 Pectinex 효소나 혼합효소를 첨가하여 제조한 젤리에서는 값들이 모두 감소하는 결과를 나타냈다. 비열처리-효소 추출구에서는 Celluclast효소와 Pectinex효소를 첨가하여 제조한 젤리는 커다란 차이를 보이지 않았지만 혼합효소를 첨가하여 제조한 젤리에서는 L값이 높은 증가율을 나타냈고 a값은 녹색도를 나타내는 (-)값이 더 증가하였다. 열처리-효소 추출구 젤리가 비열처리-효소 추출구 젤리보다 맛과 조직감 면에서는 약간 우수하였으나 다른 항목들에서는 보편적으로 비열처리-효소 추출구 젤리가 더 나은 결과를 나타냈다.

• 한국식품조리과학회지
• /
• 제19권5호
• /
• pp.555-561
• /
• 2003

The purpose of this study was to analyze the microbiological hazards of dried fish (Jwieochae, Ojingeochae and Bugeochae), and to apply pretreatment methods to increase the safety of cooked dried fish within foodservice establishments. Microbiological inspections were conducted on Total Plate Count, Coliforms, E. coli, E. coli O157:H7, Staphylococcus aureus, Salmonella spp. and Listeria monocytogenes. The study results are summarized as follows. According to the Hazard analysis, there are many problems showing high numbers in terms of Total Plate Count and Coliforms, which were both well over acceptable standard levels. E. coli and Staphylococcus aureus were detected at certain foodservice establishments, while E. coli O157:H7, Salmonella spp. and Listeria monocytogenes were not detected at all. By applying various pretreatment methods, such as washing, blanching, pan frying and microwave heating, the levels of microbiological hazards were able to be controlled and lowered. Blanching was the most effective method, followed by panfrying, microwave heating and washing. The Total Plate Counts gradually decreased with increasing number of times washed and seconds panfried. From these results, it is concluded that to guarantee food safety, cooked dried fish raw materials should be kept hygienically and appropriate pretreatment methods applied before cooking.

• Journal of Biosystems Engineering
• /
• 제32권2호
• /
• pp.121-129
• /
• 2007

This study was conducted to elucidate extraction efficiency by microwave technique in comparison with sonication technique for extraction of insecticide residue in pear. In the analysis of the extraction efficiency of microwave for a pear spiked with imidacloprid, the extraction efficiency by microwave power of 300 W with extraction temperature of $80^{\circ}C$, heating time of 1 to 3 minute was shown to be similar with the extraction time 20 minutes by sonication. The optimal condition. in consideration of economical condition and treatment time, for microwave extraction of imidacloprid in the pear were 300 watts of power supply, $100^{\circ}C$ of extraction temperature, 1 minute of heating time and 10 mL of acetone volume. A new microwave vessel was developed to rapidly process the sample of the insecticide imidacloprid residues in the pear. This vessel was designed to include a reaction chamber and a filtration equipment, and a gathering chamber. The system could curtail a pretreatment time to 21 minutes than sonication and 7.9 minutes than the previous microwave vessel.

• Journal of Microbiology
• /
• 제39권1호
• /
• pp.17-23
• /
• 2001

Various pretreatment procedures and selective media were applied to assess the optimal conditions for the isolation of rare actinomycetes from soil. Pretreatment of wet-heating for 15 min at 70$^{\circ}C$ and phenol treatment of soil suspension were the most effective methods for the isolation of these microorganisms. Hair hydrolysate vitamin agar (HHVA) was the most suitable medium for the recovery of rare actinomycetes. Thirty-five rare actinomycete strains were chosen using selective isolation approaches, then morphological and chemical properties of the isolates were determined. The isolates belonged to one of the following genus, Micromonospora, Microbispora, Actinoplanes and Streptosporangium.

• Environmental Engineering Research
• /
• 제14권1호
• /
• pp.48-52
• /
• 2009

Solubilization of sewage sludge creates favorable conditions for anaerobic microorganisms to produce biogas. In this paper, we quantify the effect of heating pretreatment on the degree of solubilization of sewage sludge. The pretreatment process was carried out using a lab-scale industrial microwave unit (2450 MHz frequency). Response surface analysis was applied to determine the combination of temperature-increase rate (ramp rate) (2.9 to 17.1 ${^{\circ}C}$/min) and terminal temperature (52 to 108${^{\circ}C}$). Both ramp rate and temperature significantly affected the solubilization degree of sludge. Within the design boundaries, the conditions predicted to maximize the solubilization degree of 15.8% were determined to be 2.9 ${^{\circ}C}$/min and 104${^{\circ}C}$.