• Applied Chemistry for Engineering
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• v.30 no.3
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• pp.313-315
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• 2019

A new synthetic method for N-hydroxysuccinimide (NHS), which is widely used in fine chemical and cosmetic industries, was developed. In a conventional synthesis, NHS is obtained by reacting $NH_2OH$ with succinic anhydride in a yield of about 70% using strong acid as a catalyst, which has an advantage of obtaining NHS relatively easily. However, it is expensive because of using a high cost succinic anhydride. In order to overcome this issue, we developed a new synthetic method for NHS with a moderate yield of 80% using a low cost succinic acid instead of succinic anhydride, alongside a stable Lewis acid catalyst, Zn acetate. As a result of the economic evaluation, it was confirmed that the cost reduction effect was about 15%.

• Journal of the Korean Chemical Society
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• v.47 no.6
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• pp.675-678
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• 2003

• Korean Journal of Bronchoesophagology
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• v.13 no.2
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• pp.82-84
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• 2007

Treatment options for anastomotic recurrence occurring after Ivor Lewis operation are limited. Reoperation for resection can be technically challenging and several reports suggest a potential survival benefit from re-resection. Specific care must be taken to avoid compromise of the previously transposed conduit to not endanger its vascular supply and the recurrent nerves in either the chest or neck. We report our surgical experience of a case of esophagogastric anastomotic site recurrence occurring after Ivor Lewis operation with review of literatures.

• 한국연소학회:학술대회논문집
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• 2014.11a
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• pp.129-132
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• 2014

A study on laminar coflow jet flames diluted with helium and nitrogen has been conducted to investigate self-excitations. The stability map was provided with a function of nozzle exit velocity and fuel mole fractions of propane or methane. The results show that there exist three types of self-excitations; (1) buoyancy-driven self-excitation (BDSE), (2) Lewis number induced self-excitation coupled with buoyancy (LCB) and (3) Lewis number induced self-excitation (LISE).

• Journal of the Korean Society of Combustion
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• v.12 no.2
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• pp.34-41
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• 2007

The dynamic behaviors of counterflow non-premixed flame have been investigated experimentally to study effects of heat losses and Lewis number on edge flame oscillation, which result from the advancing and retreating edge flame motion of outer flame edge at low strain rate flame. For low strain rate flame, lateral conduction heat loss in addition to radiation heat loss could be more remarkable than the others. Oscillatory instabilities appear at fuel Lewis number greater than unity. But excessive lateral conduction heat loss causes edge flame instability even at fuel Lewis number less than unity. The excessive heat loss caused by the smaller burner diameter in which the flame length is an indicator of lateral conduction heat loss extends the region of flame oscillation and accelerates oscillatory instability in comparison to the previous study with the burner diameter of 26mm. Extinction behaviors quite different from the previous study are also addressed.

• Resources Recycling
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• v.27 no.5
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• pp.3-8
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• 2018

Acid-base reaction together with oxidation-reduction reaction is an important reaction occurring in the aqueous phase. The definition by Lewis on the acid and base is more comprehensive than several definitions. HSAB theory has been introduced to consider the difference in the reactivity among the acids/bases. In this paper, several acid-base reactions were analyzed by applying the definition of acid and base. Moreover, the background of the introduction of HSAB and its application was explained.

• Korean journal of applied entomology
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• v.51 no.3
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• pp.265-269
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• 2012

The Korean Boletoxenus known as fungivorous are taxonomically reviewed as two species including a new recorded species, Boletoxenus incurvatus (Lewis, 1894). And the host fungus of B. incurvatus is revealed through this study. Therefore, we provide the taxonomical information as well as the ecological information on the host fungi of the Korean Boletoxenus species.

• Journal of Chest Surgery
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• v.37 no.2
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• pp.193-196
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• 2004

Benign gastrobronchial fistula (GBF) after Ivor Lewis operation is a very rare and serious complication. We describe a patient with GBF who was successfully managed on the single-stage repair, 15 months after the Ivor Lewis operation. After the division of the GBF, the bronchial and gastric defects were closed directly. The omental flap and the pedicled 5th. intercostal muscle flap were interposed between the closed defects. The literature of this subject is reviewed and discussed.

• Microbiology and Biotechnology Letters
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• v.21 no.3
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• pp.247-255
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• 1993

Antitumor activity of Lactobacillus casei YIP 9018(LC9018) was studied in mice by using sarcoma 180(S-180) and Lewis lung carcinoma (3LL). Following the eatablishment of in vivo tumor models such as ascites form S-180, solid form S-180 and 3LL for estimating antitumor activity of Lactobacilli, optimal dose and injection route of heat-killed LC9018 for supperssion of local tumor were examined. Administration of 100ng/mouse of LC9018 significantly inhibited the growth of ascites form S-180, solid form S-180 and 3LL.

• Transactions of the Korean Society of Mechanical Engineers
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• v.13 no.1
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• pp.135-139
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• 1989

The flame initiation of an infinite fuel system exposed to a planar ignition kernel has been investigated numerically. The aim has been to promote an understanding of the flame initiation by using the simplest mathematical formulation which retains the essential physical features. It has been found that there exists a minimum ignition energy below which a combustion wave cannot be initiated. For a fixed value of Lewis number, the same flame progation velocity has been obtained irregardless of the amount ignition energy supplied. Furthermore, for a fixed energy input there is a maximum Lewis number over which the flame cannot be initiated.