• Elastomers and Composites
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• 제6권1호
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• pp.53-70
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• 1971

We have studied the blending effects of cis-1,4-polybutadiene (CBR) and styrene-tutadiene rubber at various blending ratios of 100 : 0, 70 30, 50 : 50, 30 : 70, 0 : 100, and of carbon black ISAF and HAP at various compounding ratios of 45 PHR, 55 PHR, 65 PHR, for tyre tread rubber. The results obtained are summerized as follows; 1. For tyre tread rubber, it was found to increased efficiency to use SBR polymer only than to use the blending ratio CB/SBR=30/70 below. But it was observed that the latter was adapted for the bus or truck tyre and the former for the passenger tyre. 2. Excellent efficiency was obtained in case of carbon black compounding ratio of 55%, and also the compounding of ISAF made better efficiency than that of HAF. 3. Carbon black was more efficient to SBR than to CB. 4. For the aging ratio, the compounding rubber of NR was the highest, and the ratio was decreased in order of the compounding rubber of oil-extended SBR or CB polymer only, the compounding rubber of non oil-extended SBR or CB polymer only, and the blending rubber.

• Elastomers and Composites
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• 제22권2호
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• pp.109-120
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• 1987

In this study, as one of the developing ways of the functional elastomer, improvement of the functionality of CB-BR was attemped through stabilization. At first the stabilization effect of CB-BR and the concentration dependancy in CB-BR were determined. Then, triazine thiol derivative(BPTT) was synthesized by reacting p-aminodiphenylamine with cyanuric chloride. Further the functional mechanism and the effects of the antioxidants were investigated using BPTT together with other various antioxidants in liquid and solid states. The results obtained are as follows: 1) The aging of CB-BR depended on the concentration and temperature. Thus, at a low temperature of $50^{\circ}C$, the aging proceeded with gel formation; at high temperature above $100^{\circ}C$ and in above 4wt% concentration, the aging occured by the formation of gel. And in concentrations below that, the aging proceeds with a decomposition caused by oxygen attacked to elastomer molecules. 2) The effect of antioxidation of CB-BR in the liquid state was at it's best when the MBIZ and BPTT were used at $110^{\circ}C$, 4hrs after the oxidation. 3) The effect of antioxidation of CB-BR in the solid state was the best choice the simultaneous use of NDBC and BPTT at $50^{\circ}C$, 30days after the oxidation.

• 한국식품영양과학회지
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• 제40권8호
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• pp.1121-1127
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• 2011

1. 현재까지 국내에 개발된 팥의 이용성 증진을 위해 다양한 종피색의 팥 품종에 대해 앙금을 제조하여 품질 특성을 비교 분석하였다. 팥 품종별 수분함량은 8.2~11.1 g/100 g, 조단백질은 15.4~20.6 g/100 g, 조회분은 3.3~3.6 g/100 g을 나타내었으며, 칼륨은 칠보팥(CB)과 홍언팥(HE)이 각각 875.1 및 873.1 mg/100 g으로, 칼슘은 중부팥(JB)과 금실팥(KS)이 각각 73.6 및 73.2 mg/100 g으로, 마그네슘은 연금팥(YK)이 131.4 mg/100 g으로 높은 함량을 보였다. 앙금 수율은 습물중은 188.3~204.7%, 건물중은 62.1~66.0%의 범위로 유의적인 차이를 보이지 않았다. 앙금의 명도는 종피색이 밝은 연금팥(YK)과 금실팥(KS)이 각각 67.0 및 68.0으로 가장 높은 값을 보였으며, 종피색이 검정색인 칠보팥(CB)이 54.0으로 가장 어두운 것으로 나타났다. 적색도(a-value)와 황색도(b-value)는 연금팥(YK)이 각각 6.6 및 12.8로 가장 높은 값을 보였고 칠보팥(CB)이 각각 3.8 및 5.9로 가장 낮았다. 앙금의 평균입자직경은 중원팥이 121.10 ${\mu}m$로 가장 크게 나타났고 중부팥이 100.80 ${\mu}m$로 가장 작은 값을 나타냈으며, 입도분포는 전체적으로 유의적인 차이를 보이지 않았다. 앙금의 입자는 타원형의 모양을 가지고 있었으며, 세포막과 단백질이 둘러싸서 표면이 거칠게 나타났다. 품종별 팥 앙금의 수분결합력 및 용해도는 유의적인 차이를 나타내 지 않았다. 팥 앙금의 호화점도특성 중 최고점도, 최저점도, 최종점도 및 치반점도는 중부팥(JB)이 각각 3.79, 3.75, 7.33 및 3.54 RVU로 가장 높은 값을 나타났고 칠보팥(CB)이 1.21, 1.17, 2.46 및 1.25 RVU로 가장 낮게 나타났다. 이상의 결과를 볼 때 식품가공에서 팥 앙금의 선택은 관능적으로 색에 가장 많은 영향을 미치므로 생산하고자 하는 제품의 특성을 고려하여 팥 앙금을 사용하는 것이 바람직할 것으로 생각된다.

• 대한수의학회지
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• 제34권1호
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• pp.85-91
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• 1994

A study on the isolation of Yersiniae from the feces of wild animals(mammals 376, birds 19 and reptiles 13) in zoo and the biotype and serotype and susceptibility of 12 antibiotics was carried. Out of 408 animals, Yersiniae were isolated from 28 animals(6.9%). Of 28 isolates, 27 isolates(96.4%) were Y. enterocolitica and 1(3.6%) was Y. kristensenii. According to the species, 25(6.6%) of Y. enterocolitica and 1(0.3%) of Y. kristensenii were isolated from 376 mammals, 2(15.4%) of Y. enterocolitica from 13 reptiles but not isolated from 19 birds. According to the eating pattern, 8(5.2%) of Y. enterocolitica were isolated from 155 carnivora, 13(10%) of Y. enterocolitica from 123 herbivora, and 6(4.9%) of Y. enterocolitica and 1(0.8%) of Y. enterocolitica from 123 omnivora. Out of 27 isolates of Y. enterocolitica, all were biotype 1. And predominant serotype was 0:21(40.7%), and 0:5(37.0%), 0:6(11.1%), 0:1(3.7%), 0:9(3.7%) and untypable(3.7%). Yersiniae isolated from zoo animals were resistant to cephalothin(100%), ampicillin(96.4%), carbenicillin(96.4%) and tetracycline(14.3%) and streptomycin(3.6%) and susceptible to chloramphenicol(100%), colistin(100%), gentamicin(100%), kanamycin(100%), nalidixic acid(100%), polymyxin B(100%) and tobramycin(100%). The predominant multiple resistance pattern was Am-Cf-Cb(82.1%), and Am-Cf-Cb-Te(10.7%) and Am-Cf-Cb-Te-Sm(3.7%).

• Asian-Australasian Journal of Animal Sciences
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• 제24권4호
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• pp.517-524
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• 2011

The effect on sow milk of variable levels of cassava in lactating sow diets was analyzed in an attempt to explain the beneficial effects reported by producers of including cassava as a basal feed. Twenty crossbred lactating sows were randomly assigned to five dietary treatments. The treatments were: i) broken rice (BR) as the basal feed (BR100), ii) 50% of BR replaced with cassava chip meal (CCM) (CM50), iii) 75% of BR replaced with CCM (CM75), iv) CCM as the basal feed (CM100), and v) dried boiled cassava chips (CCB) as the basal feed (CB100). The hydrocyanide (HCN) content of CCB was reduced to be intermediate between HCN in the no cassava (BR100) and the 50% cassava (CB50) diets. Hydrocyanide was 0.54, 3.24, 4.41, 5.43 and 1.77 ppm in the BR100, CM50, CM75, CM100 and CB100 diets, respectively. Increasing cassava did not affect feed intake (p>0.05), but increased HCN intake (p<0.01). Milk composition was analyzed for protein, fat, lactose, solids not fat (SNF) and total solids (TS). Milk quality was analyzed for total microbes, coliform bacteria, thiocyanate ($SCN^-$), lactoperoxidase (LPO), and glutathione peroxidase (GPx) activity. At farrowing, sow milk composition was not affected by experimental diets (p>0.05), but milk $SCN^-$ increased as the intake of HCN increased in sows diets (p<0.01), $r^2$ = 0.96. At mid-lactation (day 14), milk composition was not affected (p>0.05). The milk quality levels of $SCN^-$ were 9.4, 10.3, 10.5, 11.6 and 9.1 ppm for the BR100, CM50, CM75, CM100 and CB100 diets, respectively (p = 0.01). The LPO contents were 16.41, 42.13, 51.42, 53.94 and 22.81 unit/L, respectively (p = 0.03). There was no GPx activity found in sow milk. When BR was replaced with cassava meal, total microbes and coliforms were reduced 78% and 87%, respectively, by the influences of HCN. The reported beneficial effects of cassava chip meal as a basal feed in lactating sow diets is manifested by improved performance of suckling pigs. This is due to beneficial, non-toxic levels of HCN in the diets. Besides passing HCN to suckling pigs in the form of $SCN^-$, sow milk may also benefit suckling pigs with the observed (day 14) increase in lactoperoxidase content and reduction in coliform bacteria.

• 한국식품영양과학회지
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• 제42권3호
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• pp.487-496
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• 2013

커피의 생리활성을 증진시키기 위해 고체발효를 이용하여 인도네시아산 Mandheling 커피생두에 3종의 버섯 균사체(Phellinus linteus, PL; Hericium erinaceum, HE; Ganoderma lucidum, GL) 및 2종의 홍국균 균사체(Monascus purpureus, MP; Monascus ruber, MR)를 배양하였다. 균사체-고체발효 커피생두를 로스팅하여 얻은 원두커피는 decoction법에 의한 열수추출물과 reflux에 의한 에탄올추출물로 조제하였는데, 열수추출물(HW, 수율 17.7~25.3%)은 에탄올추출물(EE, 9.5~12.2%)보다 더 높은 수율을 나타내었다. 2종의 홍국균 균사체-고체발효 커피생두로부터 조제된 원두커피 열수추출물(MP-CB-HW, MR-CB-HW)은 비발효 원두커피 또는 3종 버섯 균사체-고체발효 원두커피 열수추출물보다 높은 총 폴리페놀 및 플라보노이드 함량과 DPPH 자유라디칼 소거능을 나타내었다. 또한, 홍국균 균사체-고체발효 원두커피 중에서도 MR-CB-HW는 가장 높은 마크로파지 활성과 마이토젠 활성을 나타내었다(CB-HW의 1.32배와 1.40배). MP-CB-EE와 MR-CB-EE는 $100{\mu}g/mL$의 시료농도에서 세포에 대한 독성을 나타내지 않으면서도 LPS로 유도된 RAW 264.7 세포의 산화질소(NO)의 생성을 효과적으로 억제하였다(LPS 처리군의 38.6과 37.0%). 한편, 홍국균 균사체를 이용한 고체발효는 카페인 함량에 영향을 주지 않으면서 클로로겐산을 유의적으로 증가시켰다($76.21{\sim}76.73{\mu}g/mL$). 결론적으로 원두커피의 생리활성은 M. purpureus 또는 M. ruber와 커피생두의 고체발효에 의해서 증진되었으며 이러한 결과는 홍국균-고체발효 원두커피가 기능성 커피음료의 소재로 이용될 가능성을 제시하는 것으로 사료된다.

• Journal of the Korean Wood Science and Technology
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• 제37권5호
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• pp.421-425
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• 2009

This research investigates the effect of copper retention on copper leaching in wood treated with copper-based preservatives. Radiata pine (Pinus radiata D. Don) sapwood samples were ground in a Wiley mill equipped with a 20-mesh screen. The ground wood was vacuum-treated with various concentrations of alkaline copper quat (ACQ), bis-(N-cyclohexyl-diazeniumdioxy)-copper (CB-HDO), and copper azole (CUAZ). The treated samples were conditioned at $70^{\circ}C$ and 100% RH for 72 hours. The samples were leached by using the distilled water for four weeks, and the copper contents in each sample were measured by X-ray spectroscopy. As expected, the copper leaching was increased with increasing of copper retention. The copper leaching from the ACQ and CB-HDO treated samples were gradually decreased with increasing copper retention: however, the copper losses from the CUAZ treated samples appeared to be proportionally increased with the increase in copper retention in all retention levels tested. The results indicate that at the conditions of the same copper retention ACQ and CB-HDO treated wood have a better leaching resistance compared to CUAZ treated wood.

• Smart Structures and Systems
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• 제29권2호
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• pp.351-359
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• 2022

The present study investigated the synergistic effects of carbon nanotube (CNT) and carbon black (CB) inclusions on the piezoresistive sensing behaviors of cementitious composites. Four different CNT and CB combinations were considered to form different conductive networks in the binder material composed of Portland cement and fly ash. The cement was substituted with fly ash at levels of 0 or 50% by the mass of binder. The specimens were cured up to 100 days to observe the variations of the electrical characteristics with hydration progress, and the piezoresistive sensing behaviors of the specimens were measured under cyclic loading tests. The fabricated specimens were additionally evaluated with flowability, resistivity and cyclic loading tests, and morphological analysis. The scanning electron microscopy and energy disperse X-ray spectroscopy test results indicated that CNT and CB inclusion induced synergistic formations of electrically conductive networks, which led to an improvement of piezoresistive sensing behaviors. Moreover, the incorporation of fly ash having Fe³⁺ components decreased the electrical resistivity, improving both the linearity of fractional changes in the electrical resistivity and reproducibility expressed as R² under cyclic loading conditions.

• Pediatric Infection and Vaccine
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• 제6권2호
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• pp.210-218
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• 1999

목 적 : 저자들은 소아에서 배양으로 확진된 장바이러스 감염의 역학 및 임상적 특성을 규명하고자 하였다. 방 법 : 1996년 1월부터 1998년 12월까지 한림대학교 부속 한강, 강암, 동산, 강동 및 춘천 성심병원 소아과에 입원하여 장바이러스가 배양된 환아를 대상으로 각 바이러스의 유행 양상, 성별, 연령 및 임상양상을 분석하였다. 결 과 : 장바이러스는 대변 245례중 126례(51.4%), 비인두흡인물 89례중 15례(16.8%) 뇌척수액 1,835례중 195례 (10.6%)에서 배양되었다. 이중 echovirus (Echo)는 273(30형 197, 9형 46, 6형 17, 미분류 13)례. coxsackievirus B(CB)는 24(2형 11, 5형 2, 미분류 11)례. coxsackievirus A(CA) 24형이 7례, 분류되지 않은 장바이러스가 32례이었다. 2) 장바이러스는 '96년에 65례 (Echo 9형 46례), '97년에 239례 (Echo 30형 197례), '98년에 32례 (CB 15례 : CB 2형 9례)가 분리되었으며, '66년은 8~10월, '97년과 '98년은 5~7월에 주로 발생하였다. 3) 장바이러스 감염아의 평균 연령은 $62.1{\pm}38.0$개월이었고 74.6%가 7세 미만이었으며, 남아 203명 (67%), 여아 100명 (33%)으로 남아에서 많이 발생하였다. 4) 장바이러스가 배양된 305명 환아 중 242명 (79.3%)에서 무균성 뇌막염이 확진되었으며, 사망한 환아는 없었다. 결 론 : 장바이러스 유행은 늦봄부터 가을 사이에 발생하였고, '96년은 Echo 9형, '97년은 Echo 30형, '98년은 CB 2형이 주된 원인이었으며, 대변의 배양율이 가장 높았다. 장바이러스가 배양된 한아는 남아가 많았고 학동 전기 소아에서 호발하였으며, 79.3%가 무균성 뇌막염으로 진단되었다.

• Elastomers and Composites
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• 제52권4호
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• pp.237-241
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• 2017

The tensile strength (TS) and elongation-at-break (EB) loss of a CR/CB rubber composite sample prepared for the automotive parts were measured after accelerated thermal ageing at temperatures of 100, 120, 140, and $150^{\circ}C$. The change in TS was observed to be linear from the master curve prepared using the time-temperature superposition-principle (TTSP). An Arrhenius type of shift factor, $a_T$ was used to predict the life time of the sample, and a plot of ln $a_T$ vs. 1/T was also shown to be linear. The activation energy ($E_a$) of the sample was calculated as 70.30 kJ/mole from the Arrhenius plot. The expected life time of the sample was predicted at the given operating conditions by applying Arrhenius analysis. Assuming the $E_a$ value was constant at lower operating condition, life time of the sample was calculated as 2.3 years when the life limit was set as time to reach the 20% decrease of the initial TS value at operating temperature of $40^{\circ}C$.