• 제목/요약/키워드: Weight losses

검색결과 349건 처리시간 0.026초

효소처리에 의한 면직물의 개질 (Modification of Cotton Fiber by Enzymatic Treatment)

  • 조민정;김태경;임용진;이상복
    • 한국염색가공학회지
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    • 제6권3호
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    • pp.15-26
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    • 1994
  • Cotton fabrics were treated with the cellulase which is an enzyme to decompose cellulose and its actional mechanism is known. The optimum condition of the cellulase to the cotton fabrics and the weight losses, tensile strengths of the treated cotton fabrics were also obtained. The cellulase performs a specific catalytic action on the ${\beta}-1$, 4-glucosidic bonds of the cellulose molecules and hydrolyzes them. For that reason, the negative surface charges of the cotton fabrics were increased by additional generation. of hyrdoxyl groups. The increased surface charges cause the decrease of dye adsorption by inhibiting the approach of the anions of direct dyes. But, it was overcome by the use of enough amount of salt, it means that sodium ions of the salt neutralize the almost all of negative charges of the cotton fabrics. The improvement of the water absorbency is also due to the increased hydroxyl groups In addition, their handles including the mechanical properties were measured and caculated by KES system which is a measuring apparatus that numerizes and objectificates human's feeling, especially touch. As the results, we knew that KOSH(stiffness) and FUKURAMI(fulness & softness) were decreased and that NUMERI(smoothness) was increased.

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Salmonellosis in swine: Clinical perspectives

  • Shim, Minkyung;Hong, Sanghyun;Seok, Min-Jae;Kim, Hyeun Bum
    • 농업과학연구
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    • 제43권3호
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    • pp.320-329
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    • 2016
  • Salmonella is one of the most important food-borne zoonotic pathogens, causing acute or chronic digestive diseases such as enteritis. The acute form of enteritis is common in young pigs of 2 - 4 months of age. The main symptoms include high fever ($41-42^{\circ}C$), loss of appetite, and increased mortality within 2 - 4 days of onset of the disease. It is often the cause of increasing mortality, decreasing growth rate and reducing feed efficiency of piglets. In the case of chronic enteritis in pigs, the main symptom is weight loss due to the continuing severe diarrhea. Salmonella enterica serovar Typhimurium and Salmonella enterica serovar Choleraesuis are typical pig adapted serotypes, which cause one of four major syndromes: enteric fever, enterocolitis/diarrhea, bacteremia and chronic asymptomatic carriage. These syndromes cause a huge economic burden to swine industry by reducing production. Therefore, it is necessary that swine industries should strive to decrease Salmonellosis in pigs in order to reduce economic losses. There are several measures, such as vaccination to prevent salmonellosis, that are implemented differently from country to country. For the treatment of Salmonella, ongoing antibiotic treatment is needed. However constant doses of antibiotics can be a problem because of antibiotic resistance. Therefore, the focus should be made more on prevention than treatment. In this review, we addressed the basic information about Salmonella, route of infection, clinical symptoms, and prevention of Salmonellosis.

벼이삭선충이 수도의 생육 및 수량에 미치는 영향 (Studies on the Effects of Inoculation Density of White-Tip Nematode, Aphelenchoides besseyi, on the Growth and Yield Losses of Rice)

  • 한상찬;조현제
    • 한국응용곤충학회지
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    • 제18권3호
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    • pp.133-136
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    • 1979
  • 벼이삭 선충의 피해를 구명코저 접종시험을 실시하였다. 1. 선충의 기생은 벼의 생육 특히 분얼수에 많은 영향을 주었다. 2. 피해경율은 온도 상승과 더불어 증가하여 출수후에는 약 3배로 늘었다. 3. 생육 및 수량에 영향을 줄 수 있는 피해경율은 $13\%$이상이다. 즉 피해발현 초기에 $5\%$이하일 때는 생육과 수량에 영향이 없었고 $13\%$일때 $19\%,\;21\%$이면 $22\%$의 감수를 초래하였다. 4. 수량구성요소별로는 1000립중 립수 수수의 순으로 영향을 받았다.

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Effect of Microstructure on the Corrosion Resistance of Nd-Fe-B Permanent Magnets

  • Li, Jiajie;Li, Wei;Li, Anhua;Zhao, Rui;Lai, Bin;Zhu, Minggang
    • Journal of Magnetics
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    • 제16권3호
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    • pp.304-307
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    • 2011
  • High performance Nd-Fe-B magnets can be manufactured by both sintering and hot deformation. The corrosion behaviors of the magnets prepared by the two processes were compared. Effect of microstructure on the corrosion resistance of Nd-Fe-B magnets was also investigated. A neutral salt spray test (NSS) was performed for the different-processed magnets. The weight losses of the samples after the corrosion test were measured. The corrosion microstructures were observed using a scanning electron microscope. It shows that the corrosion resistance of hot deformed magnets is much better than that of the sintered ones because the grain size and the distribution of Nd-rich phases of the hot deformed magnets are much finer and more uniform than those of the sintered ones. The different microstructure between the sintered and the hot deformed magnets causes the different corrosion behavior.

Studies on hydrophobic drug-soluble carrier coprecitates 2

  • Shin, Sang-Chul
    • Archives of Pharmacal Research
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    • 제2권1호
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    • pp.49-64
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    • 1979
  • In an atempt to elucidate further physicochemical properties of furosemide-PVP coprecipitates, extensive investigations such as TLC, UV,IR, NMR, X-ray diffraction, TGA and DTA studies were carried out for the furosemide test systems. X-ray diffraction studies revealed that the pure furosemide and the furosemide contained within a physical mixture were crystalline in nature. However, there was no crystallinity evident in the 1:5 furosemide-PVP 40,000 coprecipitate system, even after standing for two years. The various ratio furosemide-PVP 40,000 coprecipitate systems revealed that the coprecipitate containing a greater amount of PVP 40,000 than that of furosemide showed a crystalline state of furosemide and that the minimum amounts of PVP to make amorphous form of furosemide was 1:1 ratio of furosemide to PVP. From the furosemide-PVP coprecipitate systems with PVP of different molecular weights of 10,000, 40,000 and 360,000, all the 1:1 ratio coprecipitates did not exhibit any crystallinity of furosemide, whereas all the 2:1 ratio coprecipitates showed a presence of crystalline furosemide. All the coprecipitated preparations with PEG 4,000 and with PEG 6,000 showed the diffraction peaks indicating the presence of crystalline furosemide. The comparison of infrared spectra of the physical mixture and the coprecipitate showed an interaction such as association between the functional groups of furosemide and PVP in the molecular level, whereas the studies by TLC, UV and NMR showed its dissociation in methanol solution. The weight losses in TGA curves showed all the same patterns. However, a little different transition form in DTA thermograms was shown between the physical mixture and the coprecipitate, indicating the different thermal property.

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태양광발전을 위한 고효율 승압형 전력변환장치 (The High efficiency Buck Power Conversion System for Photovoltaic Power Generator)

  • 박경원;김영철;김준홍;서기영;고희석;이현우
    • 한국조명전기설비학회:학술대회논문집
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    • 한국조명전기설비학회 1997년도 추계학술발표회논문집
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    • pp.88-92
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    • 1997
  • Power conversion system must be increased swiching frequency in order to achieve a small size, a light weight and a low noise, However, the swiches of converter are subjected to high switching power losses and switching stresses. As a result of those, the power system brings on a low efficiency. In this paper, the authors propose a DC-DC boost converter of high power by partial resonant switch method (PRSM). The switching devices in a proposed circuit are operated with soft swiching and the control technique of those is simplified for switch to drive in constant duty cycle. The partial resonant circuit makes use of a inductor suing step up and a condenser of loss-less snubber. Also the circuit has a merit which is taken to increase of efficiency, as if makes to a regeneration at input source of accumulated energy in snubber condenser without loss of snubber in conventional cirvuit. The result is the the switching loss is very low and the efficiency of system is high. The proposed converter is deemed the most suitable for high power applications where the power switching devices are used.

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압전 변압기를 이용한 멀티 램프 구동용 인버터 설계 (Design of Inverter for Driving the Multi-lamp using an Piezoelectric Transformers)

  • 조성구;임영철;양승학
    • 전력전자학회논문지
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    • 제10권2호
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    • pp.130-137
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    • 2005
  • LCD는 광변조기능을 가지는 수광 소자로서 발광원인 백라이트를 필요로 하는데 일반적으로 냉음극 방전램프(CCFL: Cold Cathode Fluorescent Lamp)가 사용된다. 기존의 권선형 변압기를 이용한 인버터를 구성하여 멀티램프를 구동하고 있지만 이는 코어나 권선 손실에 의한 효율 저하와 부피나 중량의 증가, 그리고 과열에 의한 화재의 위험성을 가지고 있다. 이러한 문제들을 해결하기 위해 본 논문에서는 압전 변압기를 이용한 멀티램프 구동용 인버터를 설계 지침에 따라 구성하였다. 인버터 하나로 압전 변압기를 병렬로 연결하는 방식을 이용하였고, 또한 전류 부담이 적은 외관 전극 형광 램프(EEFL: External Electrode Fluorescent Lamp)를 이용한 멀티램프 구동 방법이 압전 인버터에 적용 가능한지를 확인하였다.

단일 펄스 소프트 스위칭을 이용한 고역률 고효율 DC-DC 컨버터 (High Power Factor and High Efficiency DC-DC Converter using Single-Pulse Soft-Switching)

  • 정상화;권순걸;서기영;이현우;곽동걸;김영철
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2003년도 하계학술대회 논문집 B
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    • pp.1148-1150
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    • 2003
  • Power conversion system must be increased switching frequency in order to achieve a small size, a light weight and a low noise. However, the switches of converter are subjected to high switching power losses and switching stresses. As a result of those, the power system brings on a low efficiency. To improved these, a large number of soft switching topologies included a resonant circuit has been prosed. But these circuits increase number of switch in circuit and complicate sequence of switching operation. In this paper, the authors propose a high power factor and high efficiency DC-DC converter using single-pulse soft switching by partial resonant switching node. The switching devices in a prosed circuit are operated with soft switching by the partial resonant method, that is, Partial Resonant Switch Mode Power Converter. The partial resonant circuit makes use of a inductor using step up and a condenser of loss-less snubber. The result is that the switching loss is very low and the efficiency of system is high. Also the proposed converter is deemed the most suitable for high power applications where the power switching devices are used. Some simulative results on computer results are included to confirm the validity of the analytical results.

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면류용 알칼리제 처리가 건면의 조리특성에 미치는 영향 (Effect of Alkali Salts Adding on the Cooking Quality in Dried Noodles)

  • 문태용;이성갑
    • 기술사
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    • 제33권3호
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    • pp.71-79
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    • 2000
  • The effects of alkali salts adding on the cooking quality improving in dried noodles were investigated in the good texture maintaining for preventing solid soluble losses ,through chemical analysis and actual manufacturing practice ,the following results were obtained. Experiments were took a special flour of ASW:DNS=70:30, thickening agent(TA) composed of K2CO3 58%, Na2CO3 36% and Na4P2076%, and emulsified oil(EO) mixing of corn oil 44%, polysorbate 23%, emulsifier(ester of glycerin and fatty acids) 21%, soy lecithin 12%. When the mixing ratio of TA and EO to flour, is 0.03 and 1.5%(w/w) or morel than, satisfied the good quality. The water soluble solid matters content of the lowest 3.2% in the treating group that TA and EO is 0.03 and 1.5%(w/w) respectively, comparing to the 7.3% in the control group provides a excellent cooking quality. The research achieves the similar effects at specific gravity, water absorption ratio, weight increasing rate and volume expansion ratio. According to appearance test the more treating of TA turn the noodle into deeper yellow-green color. Turning to the deeper yellow color according to the increasing of EO provides better

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위상전이 풀-브리지 DC/DC 컨버터를 이용한 차세대 고속 전철용 Battery Charger에 관한 연구 (A Study on Battery Chargers for the next generation high speed train using the Phase-shift Full-bridge DC/DC Converter)

  • 조한진;김근용;이상석;김태환;원충연
    • 한국조명전기설비학회:학술대회논문집
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    • 한국조명전기설비학회 2009년도 춘계학술대회 논문집
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    • pp.384-387
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    • 2009
  • There is an increasing demand for efficient high power/weight auxiliary power supplies for use on high speed traction application. Many new conversion techniques have been proposed to reduce the voltage and current stress of switching components, and the switching losses in the traditional pulse width modulation (PWM) converter. Especially, the phase shift full bridge zero voltage switching PWM techniques are thought must desirable for many applications because this topology permits all switching devices to operate under zero voltage switching(ZVS) by using circuit parasitic components such as leakage inductance of high frequency transformer and power device junction capacitance. The proposed topology is found to have higher efficiency than conventional soft-switching converter. Also it is easily applicable to phase shift full bridge converter by applying an energy recovery snubber consisted of fast recovery diodes and capacitors.

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