• Title/Summary/Keyword: soda

검색결과 537건 처리시간 0.029초

DC 스퍼터링을 이용한 소다라임 유리 기판상에 2차원 황화텅스텐 박막 형성 공정 (DC Sputtering Process of 2-Dimensional Tungsten Disulfide Thin Films on Soda-Lime Glass Substrates)

  • 마상민;권상직;조의식
    • 반도체디스플레이기술학회지
    • /
    • 제17권3호
    • /
    • pp.31-35
    • /
    • 2018
  • Tungsten disulfide($WS_2$) thin films were directly deposited by direct-current(DC) sputtering and annealed by rapid thermal processing(RTP) to materialize two-dimensional p-type transition metal dichalcogenide (TMDC) thin films on soda-lime glass substrates without any complicated exfoliation/transfer process. $WS_2$ thin films deposited at various DC sputtering powers from 80 W to 160W were annealed at different temperatures from $400^{\circ}C$ to $550^{\circ}C$ considering the melting temperature of soda-lime glass. The optical microscope results showed the stable surface morphologies of the $WS_2$ thin films without any defects. The X-ray photoelectron spectroscopy (XPS) results and the Hall measurement results showed stable binding energies of W and S and high carrier mobilities of $WS_2$ thin films.

맥주효모 슬러리의 쓴맛을 제거하기 위한 세척 (Washing for Debittering of Brewers Yeast Slurry)

  • 김재식
    • 한국식품과학회지
    • /
    • 제33권2호
    • /
    • pp.205-208
    • /
    • 2001
  • 맥주 공장 부산물인 맥주효모 슬러리의 쓴맛을 제거하기 위하여 가성소다 액을 이용한 세척 시험을 하였다. 효모 슬러리를 묽은 가성소다 액에 침지시키고 세척함에 따라 쓴맛이 감소하였는데, 가성소다 액의 농도를 0.05%(w/v)에서 0.25%(w/v)로 단계적으로 증가시킴에 따라 맥주 효모의 쓴맛 정도(bitterness unit)가 45 BU에서 3.0 BU까지 낮아진 반면 효모가 폐사되는 단점이 나타났다. 쓴맛 제거 정도와 세척 효모의 생존율을 동시에 고려할 때 $0.07{\sim}0.1%$(w/v) pH로는 $9.5{\sim}10.5$인 가성소다 액에 효모 슬러리를 넣고 $10{\sim}20$분 방치한 다음 0.85%(w/v) NaCl 용액으로 세척하는 것이 가장 좋은 것으로 나타났다. 세척된 효모 슬러리는 세척 전보다 백색(whiteness)이 증가되었으며 황색(yellowness)은 감소하였다. 이외에도 알코올 용액을 사용하여 세척해도 우수한 쓴맛제거 효과를 얻을 수 있었다.

  • PDF

Fabrication of a robust, transparent, and superhydrophobic soda-lime glass

  • Rahmawan, Yudi;Kwak, Moon-Kyu;Moon, Myoung-Woon;Lee, Kwang-Ryeol;Suh, Kahp-Yang
    • 한국진공학회:학술대회논문집
    • /
    • 한국진공학회 2009년도 제38회 동계학술대회 초록집
    • /
    • pp.86-86
    • /
    • 2010
  • Micro- and nanoscale texturing and control of surface energy have been considered for superhydrophobicity on polymer and silicon. However these surfaces have been reported to be difficult to meet the robustness and transparency requirements for further applications, from self cleaning windows to biochip technology. Here we provided a novel method to fabricate a nearly superhydrophobic soda-lime glass using two-step method. The first step involved wet etching process to fabricate micro-sale patterns on soda-lime glass. The second step involved application of $SiO_x$-incorporated DLC to generate high intrinsic contact angle on the surface using chemical vapor deposition (CVD) process. To investigate the effect of surface roughness, we used both positive and negative micro-scale patterns on soda-limeglass, which is relatively hard for surface texturing in comparison to quartz or Pyrex glasses due to the presence of impurities, but cheaper. For all samples we tested the static wetting angle and transparency before and after 100 cycles of wear test using woolen steel. The surface morphology is observed using optical and scanning electron microscope (SEM). The results shows that negative patterns had a greater wear resistance while the hydrophobicity was best achieved using positive patterns having static contact angle up to 140 deg. with about 80% transparency. The overall experiment shows that positive patterns at etching time of 1 min shows the optimum transparency and hydrophobicity. The optimization of micro-scale pattern to achieve a robust, transparent, superhydrophobic soda-lime glass will be further investigated in the future works.

  • PDF

Optimization of Process Variables for the Soda Pulping of Carpolobia Lutea (Polygalaceae) G. Don

  • Ogunsile, B.O.;Uba, F.I.
    • 대한화학회지
    • /
    • 제56권2호
    • /
    • pp.257-263
    • /
    • 2012
  • The selection of suitable delignification conditions and optimization of process variables is crucial to the successful operation of chemical pulping processes. Soda pulping of Carpolobia lutea was investigated, as an alternative raw material for pulp and paper production. The process was optimized under the influence of three operational variables, namely, temperature, time and concentration of cooking liquor. Equations derived using a second - order polynomial design predicted the pulp yield and lignin dissolution with errors less than 8% and 11% respectively. The maximum variations in the pulp yield using a second order factorial design was caused by changes in both time and alkali concentration. Optimum pulp yield of 43.87% was obtained at low values of the process variables. The selectivity of lignin dissolution was independent of the working conditions, allowing quantitative estimations to be established between the pulp yield and residual lignin content within the range studied.

직물형 유리섬유/에폭시 프리프레그로 피막된 판유리의 강구 충격 파괴 거동 (Steel-Ball-Impact fracture Behavior of Soda-Lime Glass Plates Bonded with Glass Fabric/Epoxy Prepreg)

  • 김형구;최낙삼
    • 한국복합재료학회:학술대회논문집
    • /
    • 한국복합재료학회 2000년도 춘계학술발표대회 논문집
    • /
    • pp.20-25
    • /
    • 2000
  • In order to study the impact fracture behavior of brittle materials, a steel-ball-impact experiment was Performed. Five kinds of materials were used in this study : soda-lime glass plates, glass/epoxy prepreg-one layer-bonded and unbonded glass plates, glass/epoxy prepreg-three layers-bonded and unbonded glass plates. Fracture patterns, the maximum stress and absorbed fracture energy were observed according to various impact velocities 40-120m/s. With increasing impact velocity, ring crack, cone crack, radial crack and lateral crack took place in the interior of glass plates. The generation of such cracks was largely reduced with glass/epoxy prepreg coating. Consequently, it is thought that the characteristics of the dynamic Impact fracture behavior could be evaluated using the absorbed fracture energy and the maximum stress measured at the back surface of glass plates.

  • PDF

중량법에 의한 김치 숙성도 판정에 관한 연구 (Study on the measurement of Kimchi maturity by weight measuring method)

  • 박우포;이상준;김재욱
    • Applied Biological Chemistry
    • /
    • 제33권3호
    • /
    • pp.257-260
    • /
    • 1990
  • 김치 숙성도 판정을 위하여 $25^{\circ}C$에서 김치를 발효시키면서 생성되는 이산화탄소를 soda lime에 흡착시키면서 6시간 간격으로 무게 증가율을 측정하였다. 발효 36시간경에 무게 증가율이 최대값을 나타내었는데, 이는 pH, 적정 산도 및 관능 검사의 결과와 비교했을 때 김치의 숙성 적기와 비교적 잘 일치하였다. 따라서 이 방법은 김치의 숙성도를 판정하는 데 유효한 것으로 사료된다.

  • PDF

Soda-borosilicate Glass를 결합재로 한 연삭 숫돌에 관한 연구 (A Stud on the Abrasive Wheels Bonded with Soda-borosilicate Glass)

  • 이희수;박정현;권오현
    • 한국세라믹학회지
    • /
    • 제16권3호
    • /
    • pp.178-183
    • /
    • 1979
  • The carborundum abrasive specimens bonded with a soda-borosilicate glass were prepared. Samples fired at specified temperatures with various mixing ratio and forming pressure were examined in terms of the structure, bonding strength, and microscopic observations. Increasing the forming pressure up to 400kg/$\cm^2$, the structure became denser in proportion to the forming pressure. The bonding strength was generally increased with increasing the mixing ratio (Vb/Vg), but the bloating phenomena were observed when samples were fired above 95$0^{\circ}C$ with mixing ratio above 20%, consequently, the bonding strength was decreased. Samples fired at the temperature range 900~95$0^{\circ}C$ with mixing ratio 15~30% had the dense structure with various grades.

  • PDF

대나무류 3종 소다-안트라퀴논 펄프 내 존재하는 hexeneuronic acid가 카파 값에 미치는 영향 (Impact of hexeneuronic acid on kappa number determination in 3 different bamboo soda-anthraquinone(AQ) pulps)

  • 송우용;이규성;이숙경;신수정
    • 펄프종이기술
    • /
    • 제48권3호
    • /
    • pp.73-79
    • /
    • 2016
  • Hexeneuronic acid in soda-anthraquinone(AQ) pulps from Moso bamboo(Phyllostachys pubescebs), Timber bamboo(Phyllostachys bambusoides) and Henon bamboo(Phyllostachys nigra var. henonis) was investigated with mercuric chloride hydrolysis and UV spectroscopic quantification. Concentration of hexeneuronic acid in bamboo pulps was $36.6-45.4{\mu}mol/g$, which contributed to 3.1-3.9 value increase of kappa number. Lower concentration of 4-O-methylglucuronic acid in bamboo xylan contributed to lower hexeneruonic acid content in bamboo pulps than those of hardwood(yellow poplar or eucalyptus) but higher than softwood(red pine).

섬유의 손상이 적은 한지 제조(제 3보)-K2CO3 증자하여 제조한 한지의 열 열화특성- (Manufacturing of Korean Traditional Handmade Paper with Reduced Fiber Damage(III))

  • 이명기;문성필
    • 펄프종이기술
    • /
    • 제31권3호
    • /
    • pp.90-95
    • /
    • 1999
  • The durability of handmade paper prepared by potassium carbonate cooking of paper multiberry (Broussonetia Kazinoki Sieb).was investigated. The potassium carbonate paper before and after heat aging had better strength properties, breaking length and folding endurance than those of the soda paper, except of lower brightness .After 30 days of heat aging , these strength properties were still maintained . however, there was almost no difference in the infrared spectra and the crystallinities calculated by X-ray diffraction curves between the potassium carbonate paper and the soda a paper. The durability of the potassium carbonate paper was though to be due to decrease in the pulp damage caused by weak alkaline cooking condition. The results indicated that the paper prepared by the potassium carbonate cooling method could have better permanence than that prepared by the conventional soda cooking method.

  • PDF

부들의 전처리를 통한 당의 추출과 소다펄프화에 관한 연구 (2) 펄프화 특성 (Sugar Extraction by Pretreatment and Soda Pulping from Cattail (Typhaceae) (2) Pulping Characteristics)

  • 김완중;이성은;서영범
    • 펄프종이기술
    • /
    • 제42권3호
    • /
    • pp.14-21
    • /
    • 2010
  • Three different species of cattails (Typha orientalis, Typha angustata, Typha latifolia) cultivated in South Korea were examined as raw materials for the production of pulp and paper. Soda pulping with anthraquinone was used for the stems and the leaves of cattail, separately. Addition of anthraquinone in soda pulping improved the yield greatly. Chemical components between three cattail species and within each species (leaves and stem) gave little differences. Average fiber length of the bleached cattail fibers was a little shorter than that of the HwBKP of Eucalyptus. Average fiber width of the cattail fibers was a half of that of the HwBKP. Compared to the HwBKP, cattail pulp gave higher breaking length, higher opacity, and better smoothness at equivalent freeness.