• 제목/요약/키워드: Zinc Powder

검색결과 201건 처리시간 0.028초

카무트 분말가루의 영양성분 분석 및 고지방식이 섭취 시 카무트 분말가루의 첨가가 흰쥐 체내에서 혈중 대사 인자에 미치는 영향 (Analysis of the General and Mineral Compositions of Kamut Powder and Effect of Kamut(Triticum turanicum Jakubz) Powder and Its Effect on Blood Parameters in Mice Fed a High-Fat Diet Supplement)

  • 신경옥
    • 한국식품영양학회지
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    • 제30권6호
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    • pp.1157-1163
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    • 2017
  • This study, analyzed the general and minerals composition of kamut and investigated its effect on blood components in mice fed a high fat diet. The content of each general component of kamut was as follows: $11.02{\pm}0.75%$ water, $13.16{\pm}1.28%$ crude protein, $1.85{\pm}0.19%$ crude fat, and $1.97{\pm}0.13%$ ash. The leptin level was the highest in the HF group($30.00{\pm}0.00ng/mL$) when compared to the control group. There was a significant decrease of $23.65{\pm}5.54ng/mL$ in the HFK group when compared to the HF group (p<0.05). The blood LDL-cholesterol concentration was the lowest in the control group at $10.00{\pm}2.00mg/dL$. The level was highest in the HF group at $28.00{\pm}0.00mg/dL$ when compared with the other groups (p<0.05). The aspartate transaminase (AST) level was significantly higher in the HFK group ($179.33{\pm}173.88U/L$) than in the control ($61.00{\pm}12.73U/L$) and HF groups ($132.00{\pm}0.00U/L$). According to the results of this study, the consumption of kamut lowers the blood LDL-cholesterol level more than the consumption of wheat flour. Additionally, kamut contains antioxidant substances such as selenium and zinc, which are thought to contribute to vascular health and thus aid in maintaining good health. Therefore, it is necessary to develop a variety of health foods using kamut; it should be used as a functional food for the maintenance of good health.

고전력 LED용 적층형 LTCC 패키징의 ZnO 조성 변화가 방열 특성에 미치는 영향 (Effects of ZnO Composition on the Thermal Emission Properties for LTCC Type of High Power LED Package)

  • 김우정;김형수;신대규;이희철
    • 마이크로전자및패키징학회지
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    • 제19권4호
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    • pp.79-83
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    • 2012
  • 신뢰성이 우수하며, 소형화가 가능하고, 우수한 열전도도의 은 전극을 이용할 수 있는 LTCC (Low temperature co-fired ceramic) 패키징은 환경 및 열에 약한 플라스틱 패키징을 대체할 것으로 기대받고 있다. 현재 LTCC 패키징의 원료 분말로는 주로 $Al_2O_3$을 사용하는데, 본 연구에서는 $Al_2O_3$보다 열전도도가 2배 우수한 ZnO을 일부 첨가 또는 대체한 조성 변화를 통하여 패키징의 열 특성 변화에 대해 연구하였다. 소량의 ZnO를 첨가하여 열전도도가 최대 25%까지 상승하는 결과가 나타났으며, 이 결과로 LED 수명이 증가할 것으로 예상된다. ANSYS 시뮬레이션 결과 열 유속의 값이 ZnO가 첨가된 경우 최대 56% 증가함을 확인할 수 있었다. 실제 LED 패키징을 제작하여 측정한 결과도 ZnO를 첨가한 LTCC 패키징은 $Al_2O_3$로만 이루어진 패키징보다 열저항이 최대 14.9% 감소하였다.

기계적 합금법으로 제조한 Mg3-xZnxSb2의 열전물성 (Thermoelectric Properties of Mg3-xZnxSb2 Fabricated by Mechanical Alloying)

  • 김인기;장경욱;김일호
    • 한국재료학회지
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    • 제23권2호
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    • pp.98-103
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    • 2013
  • $Mg_{3-x}Zn_xSb_2$ powders with x = 0-1.2 were fabricated by mechanical alloying in a planetary ball mill with a speed of 350 rpm for 24 hrs and then hot pressed under a pressure of 70 MPa at 773 K for 2 hrs. It was found that there were systematic shifts in the X-ray diffraction peaks of $Mg_3Sb_2$ (x = 0) toward a higher angle with increasing Zn for both the powder and the bulk sample and finally the phase of $Mg_{1.86}Zn_{1.14}Sb_2$ was formed at the Zn content of x = 1.2. The $Mg_{3-x}Zn_xSb_2$ compounds had nano-sized grains of 21-30 nm for the powder and 28-66 nm for the hot pressed specimens. The electrical conductivity of hot pressed $Mg_{3-x}Zn_xSb_2$ increased with increasing Zn content and temperature from 33 $Sm^{-1}$ for x = 0 to 13,026 $Sm^{-1}$ for x = 1.2 at 323 K. The samples for all the compositions from x = 0 to x = 1.2 had positive Seebeck coefficients, which decreased with increasing Zn content and temperature, which resulted from the increased charge carrier concentration. Most of the samples had relatively low thermal conductivities comparable to the high performance thermoelectric materials. The dimensionless figure of merit of $Mg_{3-x}Zn_xSb_2$ was directly proportional to the Zn content except for the compound with Zn = 1.2 at high temperature. The $Mg_{3-x}Zn_xSb_2$ compound with Zn = 0.8 had the largest value of ZT, 0.33 at 723 K.

산화물과 질산염으로 제조한 투명전극 타깃용 다성분계 IGZO 세라믹스 (Multicomponent IGZO Ceramics for Transparent Electrode Target Fabricated from Oxides and Nitrates)

  • 이현권;윤지혜;조경식
    • 한국분말재료학회지
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    • 제26권5호
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    • pp.375-382
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    • 2019
  • Homogeneous multicomponent indium gallium zinc oxide (IGZO) ceramics for transparent electrode targets are prepared from the oxides and nitrates as the source materials, and their properties are characterized. The selected compositions were $In_2O_3:Ga_2O_3:ZnO$ = 1:1:2, 1:1:6, and 1:1:12 in mole ratio based on oxide. As revealed by X-ray diffraction analysis, calcination of the selected oxide or nitrides at $1200^{\circ}C$ results in the formation of $InGaZnO_4$, $InGaZn_3O_6$, and $InGaZn_5O_8$ phases. The 1:1:2, 1:1:6, and 1:1:12 oxide samples pressed in the form of discs exhibit relative densities of 96.9, 93.2, and 84.1%, respectively, after sintering at $1450^{\circ}C$ for 12 h. The $InGaZn_3O_6$ ceramics prepared from the oxide or nitrate batches comprise large grains and exhibit homogeneous elemental distribution. Under optimized conditions, IGZO multicomponent ceramics with controlled phases, high densities, and homogeneous microstructures (grain and elemental distribution) are obtained.

Stellite bearings for liquid Zn-/Al-Systems with advanced chemical and physical properties by Mechanical Alloying and Standard-PM-Route

  • Zoz, H.;Benz, H.U.;Huettebraeucker, K.;Furken, L.;Ren, H.;Reichardt, R.
    • 한국분말야금학회:학술대회논문집
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    • 한국분말야금학회 2000년도 춘계학술강연 및 발표대회 강연 및 발표논문 초록집
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    • pp.9-10
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    • 2000
  • An important business-field of world-wide steel-industry is the coating of thin metal-sheets with zinc, zinc-aluminum and aluminum based materials. These products mostly go into automotive industry. in particular for the car-body. into building and construction industry as well as household appliances. Due to mass-production, the processing is done in large continuously operating plants where the mostly cold-rolled metal-strip as the substrate is handled in coils up to 40 tons unwind before and rolled up again after passing the processing plant which includes cleaning, annealing, hot-dip galvanizing / aluminizing and chemical treatment. In the liquid Zn, Zn-AI, AI-Zn and AI-Si bathes a combined action of corrosion and wear under high temperature and high stress onto the transfer components (rolls) accounts for major economic losses. Most critical here are the bearing systems of these rolls operating in the liquid system. Rolls in liquid system can not be avoided as they are needed to transfer the steel-strip into and out of the crucible. Since several years, ceramic roller bearings are tested here [1.2], however, in particular due to uncontrollable Slag-impurities within the hot bath [3], slide bearings are still expected to be of a higher potential [4]. The today's state of the art is the application of slide bearings based on Stellite\ulcorneragainst Stellite which is in general a 50-60 wt% Co-matrix with incorporated Cr- and W-carbides and other composites. Indeed Stellite is used as the bearing-material as of it's chemical properties (does not go into solution), the physical properties in particular with poor lubricating properties are not satisfying at all. To increase the Sliding behavior in the bearing system, about 0.15-0.2 wt% of lead has been added into the hot-bath in the past. Due to environmental regulations. this had to be reduced dramatically_ This together with the heavily increasing production rates expressed by increased velocity of the substrate-steel-band up to 200 m/min and increased tractate power up to 10 tons in modern plants. leads to life times of the bearings of a few up to several days only. To improve this situation. the Mechanical Alloying (MA) TeChnique [5.6.7.8] is used to prOduce advanced Stellite-based bearing materials. A lubricating phase is introduced into Stellite-powder-material by MA, the composite-powder-particles are coated by High Energy Milling (HEM) in order to produce bearing-bushes of approximately 12 kg by Sintering, Liquid Phase Sintering (LPS) and Hot Isostatic Pressing (HIP). The chemical and physical behavior of samples as well as the bearing systems in the hot galvanizing / aluminizing plant are discussed. DependenCies like lubricant material and composite, LPS-binder and composite, particle shape and PM-route with respect to achievable density. (temperature--) shock-reSistibility and corrosive-wear behavior will be described. The materials are characterized by particle size analysis (laser diffraction), scanning electron microscopy and X-ray diffraction. corrosive-wear behavior is determined using a special cylinder-in-bush apparatus (CIBA) as well as field-test in real production condition. Part I of this work describes the initial testing phase where different sample materials are produced, characterized, consolidated and tested in the CIBA under a common AI-Zn-system. The results are discussed and the material-system for the large components to be produced for the field test in real production condition is decided. Outlook: Part II of this work will describe the field test in a hot-dip-galvanizing/aluminizing plant of the mechanically alloyed bearing bushes under aluminum-rich liquid metal. Alter testing, the bushes will be characterized and obtained results with respect to wear. expected lifetime, surface roughness and infiltration will be discussed. Part III of this project will describe a second initial testing phase where the won results of part 1+11 will be transferred to the AI-Si system. Part IV of this project will describe the field test in a hot-dip-aluminizing plant of the mechanically alloyed bearing bushes under aluminum liquid metal. After testing. the bushes will be characterized and obtained results with respect to wear. expected lifetime, surface roughness and infiltration will be discussed.

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Hot carrier induced carrier transport property on InAs nanowires

  • Kim, Taeok;Park, Sungjin;Kang, Hang-Kyu;Bae, Jungmin;Cho, M.H.
    • 한국진공학회:학술대회논문집
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    • 한국진공학회 2016년도 제50회 동계 정기학술대회 초록집
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    • pp.362.1-362.1
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    • 2016
  • InAs nanowires were synthesized by a vapor-liquid-solid method with InAs powder. The composition and crystalline structure of nanowires were confirmed by energy-dispersive spectroscopy (EDS) and high resolution transmission electron microscopy (HRTEM), respectively. The thermal conduction of nanowires was investigated by the optical method using Raman spectroscopy: i.e., the local temperature on nanowire was determined by laser heating. As temperature increased, the Raman peaks are shifted to low frequency and broadened. The temperature dependent Raman scattering experiments was realized on InAs nanowires with different percentages of zinc-blende and wurtzite structure. The temperature dependence on the nanowire structure has been successfully obtained: the phonon scattering was more increased in InAs heretostructure nanowires, compared to the InAs nanowires with homostructure. The result strongly suggests that the thermal conduction can be effectively controlled by ordered interface without any decrease in electrical conduction.

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연고제(軟膏劑)의 경도(硬度)에 관한 연구(硏究)(III) -수종(數種)의 분말약제(粉末藥劑)가 연고제(軟膏劑)의 대수경도(對數硬度)에 미치는 영향(影響)- (The Study on the Hardness of Ointment (III) -Influences of Power on the Apparent Logarithmic Hardness of Ointments-)

  • 김종갑;김기성;이숙경
    • Journal of Pharmaceutical Investigation
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    • 제5권3호
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    • pp.66-73
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    • 1975
  • The relationship between powders and apparent logarithmic hardness of ointments were clearly demonstrated. The followings were obtained as the results. 1. Apparent logarithmic hardness of ointment were affected by the powders such as zinc oxide, salicylic acid, soluble starch. and talc. 2. The ointments which are added powder have different two slops, $k_1\;and\;k_2$. 3. The slopes, $k_1\;and\;k_2$ were directly correlated and the critical points, were proportional to $k_1\;and\;k_2$ values. 4. The slope, ka is at least $6{\sim}91$ times more sensitive, than the slope, $k_1$, and 25 times more sensitive in average. It was suggested from the results that the quantity of powers which is added to the ointment must be within the critical point.

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동시 열증착법에 의한 $CdS_{1-x}Te_{1-x}$ 삼원계 다결정 박막의 제작과 특성 (Preparation and Characteristics of $CdS_{1-x}Te_{1-x}$ Ternary Polycrystalline Thin Films by Co-evaporation)

  • 박민서;송복식;정성훈;문동찬;김선태
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 1995년도 추계학술대회 논문집
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    • pp.126-130
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    • 1995
  • $CdS_{1-x}Te_{1-x}$ polycrystalline thin films were fabricated from CdS and CdTe powder by co-evaporation method at $10^{-6}$ Torr. The Optimum evaporation condition was substrate temperature $T_{s}$=$150^{\circ}C$, evaporation time t=30 min. XRD spectrums indicated that the crystal structure chanced from zinc blonde (x$\leq$0.22) to wurtzite (x$\geq$0.96) through mixed structure (0.22$\leq$0.74) as composition value x increase to CdS. Conductive type was n-type by hot point probe method. van der Pauw method was not applicable for x<0,5 due to high hall voltages, Electrical resistivity and Hall carrier mobility were decreased as x increase, while Hall carrier concentration was increased. The optical bandgap of $CdS_{1-x}Te_{1-x}$ polycrystalline thin films measure d at R.T. had quardratic form and the bowing parameter was fitted as 1.98eV for theoretical value of 2.0eV. I-V characteristics of In/CdTe/$CdS_{x}Te_{1-x}$Au Schottky diodes showed that CdS-rich one had better forward characteristics than CdTe-rich one.

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시멘트 재료의 수밀특성에 미치는 유기 지방산 염의 영향 (Effects of the Organic Fatty Acid Salts on the Watertightness Properties of the Cementitious Materials)

  • 나승현;강현주;안광훈;송명신
    • 한국콘크리트학회:학술대회논문집
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    • 한국콘크리트학회 2008년도 추계 학술발표회 제20권2호
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    • pp.529-532
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    • 2008
  • 콘크리트의 내구성능은 시멘트 재료의 수밀성능과 밀접한 관계가 있다고 할 수 있다. 콘크리트의 내구성능 향상을 목표로 매우 다양한 수밀성능 개선 재료가 단독 혹은 복합적으로 사용되고 있다. 시멘트 재료의 수밀성능 향상을 위해 사용되는 재료로서는 천연 mineral계, 유기 지방산계, 지방산 염계 등이대표적이라 할 수 있는데 각각의 수밀성 mechanism은 차이가 있으며 또한 시멘트 재료의 수화특성에 다른 영향을 미치는 것으로 알려져 있다. 본 연구에서는 유기 지방산 염계 수밀성 재료로서 stearic salts를 사용하여 지방산염이 시멘트 재료의 수밀성능 향상에 기여하는 mechanism 및 시멘트 재료의수화특성에 대하여 연구하였으며 유기 지방산염의 첨가에 따른 시멘트 수화특성에 대하여 응결시간,flow, 단열식 수화발열 특성, 압축강도 등에 대해 측정하고, 수화물의 생성 및 변화를 확인하기 위하여 powder X-ray 회절분석 및 주사형 전자현미경 분석을 하였으며, 수밀특성에 대해서는 KS F 2609(건축재료의 물 흡수계수)에 의한 흡수계수와 시멘트 재료의 pore 특성으로 분석하였다.

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제초제 Alachlor 의 토양미생물에 의한 분해 II. 주요 분해산물의 합성과 식물독성 (Degradation of the Herbicide Alachlor by Soil Microorganisms II. Synthesis and Phytotoxicity of Major Degradation Products)

  • 이재구
    • 한국환경농학회지
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    • 제3권1호
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    • pp.1-9
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    • 1984
  • Alachlor의 토양중 분해산물인 2,6-diethyl-N-(methoxymethyl) acetanilide(분해산물 1)와 2-hydroxy-2',6'-diethyl-N-(methoxymethrl) acetanilide (분해산물 2)를 합성하였다. 분해산물 1은 실온에서 아연분말 존재하에 alachlor를 3N-염산과 반응시켜서 얻었고 분해산물 2는 alachlor를 중탄산소다의 포화용액과 $90^{\circ}C$에서 78시간 반응시켜 합성하였다. 분해산물 2는 $5{\times}10^{-4}M$$1{\times}10^{-3}M$의 농도에서 특히 어린벼에 alachlor와 거의 같은 독성을 보인 반면 분해산물 1은 그 약효를 상실하였다. 따라서 alachlor 구조중의 염소원자를 수산기로 치환해도 alachlor의 식물독성은 별 영향을 받지 않으나 수소원자로 치환할 경우는 영향을 받는 것으로 보인다.

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