• 제목/요약/키워드: Al-based

검색결과 4,858건 처리시간 0.036초

Fe-P-C-B-Al-Mo계 비정질합금의 열적.화학적 성질에 미치는 P 및 Mo의 영향 (The Effect of P and Mo for Thermal and Chemical Properties of Fe-PC-B-Al-Mo Amorphous Alloys)

  • 국진선;전우용
    • 열처리공학회지
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    • 제15권2호
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    • pp.76-81
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    • 2002
  • The melt-spun amorphous $Fe_{77-X}P_{13}C_4B_4Al_2Mo_X$(x=4~10) and $Fe_{82-X}P_XC_4B_4Al_2Mo_8$(x=9~15) alloys were found to exhibit a large supercooled liquid region(${\Delta}T_x$) exceeding 40 K before crystallization. The largest ${\Delta}T_x$ for the glassy alloys containing Mo reaches as large as 65 K for the $Fe_{69}P_{13}C_4B_4Al_2Mo_8$ alloy. The corrosion behavior of the amorphous $Fe_{77-X}P_{13}C_4B_4Al_2Mo_X$(x=4~15) and $Fe_(82-X)P_XC_4B_4Al_2Mo_8$ (x=9~17) alloys were examined by electrochemical measurements in 9M $H_2SO_4$ solution at 303 K. The addition of Mo(or P) for replacing some portion of Fe is effective in improving the corrosion resistance of the investigated Fe-based glassy alloys. They are spontaneously passivated and have a wide passive region with low passive current density.

Al계 초소성합금과 Zr계 비정질합금의 마이크로 진동성형에 관한 연구 (A Study on the Micro Vibration Forming of Al-based Superplastic Alloy and Zr-based Bulk Metallic Glass)

  • 손선천;박규열;나영상
    • 한국공작기계학회논문집
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    • 제16권6호
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    • pp.193-200
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    • 2007
  • Micro forming is a suited technology to manufacture very small metallic parts(several $mm{\sim}{\mu}m$). Al5083 superplastic alloy with very small grains has a great advantage in achieving micro deformation under low stress due to its relatively low strength at a specific high temperature range. Micro forming of $Zr_{62}Cu_{17}Ni_{13}Al_8$ bulk Metallic glass(BMG) as a candidate material for this developing process are feasible at a relatively low stress in the supercooled liquid state without any crystallization during hot deformation. In this study, the micro formability of Al5083 superplastic alloy and bulk metallic glass, $Zr_{62}Cu_{17}Ni_{13}Al_8$, was investigated with the specially designed micro vibration forming system using pyramid-shape, V-shape and U-shape micro die pattern. With these dies, micro vibration forming was conducted by varying the applied load, time. Micro formability was estimated by comparing the hight of formed shape using non-contact surface profiler system. The vibration load effect to metal flow in the micro die and improve the micro formability of Al5083 superplastic alloy and $Zr_{62}Cu_{17}Ni_{13}Al_8$ bulk Metallic glass(BMG).

Study on Mechanism and Electro-Optical Characteristics of Liquid Crystal Alignment Employing ZnO:Al Electrode

  • Kim, Mi-Jung;Oh, Byeong-Yun;Kim, Byoung-Yong;Kang, Dong-Hun;Park, Hong-Gyu;Lee, Kang-Min;Moon, Hyun-Chan;Seo, Dae-Shik
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2007년도 추계학술대회 논문집
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    • pp.433-433
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    • 2007
  • In this paper, we investigated the feasibility of applying ZnO:Al films to display devices as transparent electrodes, and reported the electro-optical (EO) characteristics of VA cells using ZnO:Al electrodes and compared them with those of VA cells using ITO electrodes. The experiment results show that a uniform vertical LC alignment and a large pretilt angle were achieved. Also, the good voltage-transmittance curve, response time, and capacitance-voltage characteristics were observed for the rubbing aligned VA-LCD using ZnO:Al electrodes m comparison with ITO electrodes. In other words, the vertical alignment mode based on the ZnO:Al electrodes showed appropriate electro-optical characteristics and high transparency in comparison with that based on the ITO electrodes. These results indicated that the transparent ZnO:Al electrodes of the liquid crystal displays could substitute the ITO electrodes.

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쌍롤 박판주조법 및 이속압연으로 제조한 고성형성 6xxx계 Al 합금 판재 (6xxx Series Al Alloy Sheets with High Formability Produced by Twin-roll Strip Casting and Asymmetric Rolling)

  • 김홍규;조재형;김형욱;이재철
    • 대한금속재료학회지
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    • 제50권7호
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    • pp.503-509
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    • 2012
  • We report on the feasibility of producing 6xxx series Al alloy sheets using a combination of twin-roll strip casting and asymmetric rolling. The Al alloy sheets produced in this study exhibited an excellent formability ($\bar{r}=1.2$, ${\Delta}r=0.17$) and mechanical properties (${\sigma}_{TS}{\sim}260MPa$, ${\varepsilon}>30%$), which cannot be feasibly obtained via the conventional technique based on ingot casting and conventional rolling. The enhanced formability as evaluated in terms of $\bar{r}$ and ${\Delta}r$ was clarified by examining the evolution of textures associated with strip casting and subsequent thermo-mechanical treatments. The evaluation of the formability leads us to conclude that the combined technique based on strip casting and asymmetric rolling is a feasible process for enhancing the formability of Al alloy sheets to a level beyond which the conventional technique can reach.

Cloud-Based Accounting Adoption in Jordanian Financial Sector

  • ELDALABEEH, Abdel Rahman;AL-SHBAIL, Mohannad Obeid;ALMUIET, Mohammad Zayed;BANY BAKER, Mohammad;E'LEIMAT, Dheifallah
    • The Journal of Asian Finance, Economics and Business
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    • 제8권2호
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    • pp.833-849
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    • 2021
  • Cloud accounting represents a new area of accounting information systems. Past research has often focused on accounting information systems and its antecedents, rather than factors that adopt cloud accounting system. The purpose of this paper is to explain the factors that influence the adoption of cloud accounting in the financial sectors. This paper applied the technology acceptance model (TAM), technology-organization-environment, and the De Lone and Mc Lean model, coupled with proposed factors relevant to cloud accounting. The proposed model was empirically evaluated using survey data from 187 managers (financial managers, IT department managers, audit managers, heads of accounting departments, and head of internal control departments) in Jordanian bank branches. Based on the SEM results, top management support, organizational competency, service quality, system quality, perceived usefulness, and perceived ease of use had a positive relationship with the intention of using cloud accounting. Cloud accounting adoption positively affected cloud accounting usage. This paper contributes to a theoretical understanding of factors that activate the adoption of cloud accounting. For financial firms in general the results enable them to better develop cloud accounting framework. The paper verifies the factors that affect the adoption of cloud accounting and the proposed cloud accounting model.

저온 알루미늄 브레이징용 Al-Cu-Si-Sn 합금 설계 및 분말 제조 (Alloy Design and Powder Manufacturing of Al-Cu-Si alloy for Low-Temperature Aluminum Brazing)

  • 김희연;박천웅;이원희;김영도
    • 한국분말재료학회지
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    • 제30권4호
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    • pp.339-345
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    • 2023
  • This study investigates the melting point and brazing properties of the aluminum (Al)-copper (Cu)-silicon (Si)-tin (Sn) alloy fabricated for low-temperature brazing based on the alloy design. Specifically, the Al-20Cu-10Si-Sn alloy is examined and confirmed to possess a melting point of approximately 520℃. Analysis of the melting point of the alloy based on composition reveals that the melting temperature tends to decrease with increasing Cu and Si content, along with a corresponding decrease as the Sn content rises. This study verifies that the Al-20Cu-10Si-5Sn alloy exhibits high liquidity and favorable mechanical properties for brazing through the joint gap filling test and Vickers hardness measurements. Additionally, a powder fabricated using the Al-20Cu-10Si-5Sn alloy demonstrates a melting point of around 515℃ following melting point analysis. Consequently, it is deemed highly suitable for use as a low-temperature Al brazing material.

Traditional Unani Plant-Based Therapies for Menopausal Symptoms in Women

  • Arshiya Sultana;Fahmida Kousar;Shahzadi Sultana;Taseen Banu;Arfa Begum
    • 셀메드
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    • 제13권14호
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    • pp.17.1-17.23
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    • 2023
  • Menopause is a physiological phase experienced by all women as part of normal aging known as menopause. Per se, menopause is not a disease, but hormonal imbalance may lead to menopausal symptoms in some women. The unani physician described that in Sinn-i-Inḥiṭāṭ/ Sinn al-Yās, Burūdat (coldness) increases lead to Ihtibās al-Tamth (amenorrhea) that can occur naturally. Besides, Khilt Dam (blood) production decreases from the liver, slight production occurs, tends towards Burūdat. Therefore, at this age, Ihtibās al-Tamth is associated with Alāmāt Sinn al-Yās(menopausalsymptoms) including weight gain, loss of appetite, hirsutism, fatigue, headache, backache, arthralgia, neck pain, general myalgia, nervousness, anxiety, depression, and insomnia. The traditional Unani manuscripts are enriched with knowledge for the management of Alāmāt Sinn al-Yās. Consequently, an extensive exploration of classical texts concerning the management of Alāmāt Sinn al-Yās was undertaken. Moreover, PubMed, Scopus, Google Scholar, and other indexing databases were thoroughly explored for evidence-based approaches to managing menopausalsymptoms. The principle management as per Unani texts is to treat the cause of Alāmāt Sinn al-Yās. Unani medicines with emmenagogue, anti-inflammatory, analgesic, cardioprotective, and neuroprotective properties are beneficial for the amelioration of Alāmāt Sinn al-Yās. Unani Herbs such as Asgandh, Aslusūs, Khārkhasak, Tagar, Shuneez, Ustukhuddus, Zafran, and Majūn Najāh possess properties and are proven scientifically for their efficacy in Alāmāt Sinn al-Yās. Hence, the substantiation and preservation of traditional knowledge assume paramount importance in facilitating prospective research and proving invaluable in the modern era. Moreover, the conduct of randomized controlled trials, systematic reviews, and meta-analyses becomes imperative.

치환성(置換性) Al 함량(含量)에 따른 석탄소요량(石炭所要量) 결정(決定)에 관(關)한 연구(硏究) (A study on determination of the lime requirement based on exchangeable aluminum content)

  • 류인수;조성진;육창수
    • 한국토양비료학회지
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    • 제7권3호
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    • pp.185-191
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    • 1974
  • 치환성(置換性) Al 함량(含量)에 근거(根據)한 석회소요량결정방법(石灰所要量決定方法)을 우리나라 밭 토양(土壤)에 대(對)하여 검토(檢討)한 목적(目的)으로 실내(室內) 및 Pot시험(試驗)을 실시(實施)하였던 바 그 결과(結果)는 다음과 같다. 1. 공시(供試)된 반토양(土壤)의 pH는 5.0-5.4이었고 치환성(置換性) Al함량(含量)은 1.1~3.0me/100g 범위(範圍)에 있어 경작년도(耕作年度)가 오래된 토양(土壤)일수록 그 함량(含量)은 적었다. 2. 항온(恒溫) 실험결과(實驗結果)에서 광질토양(鑛質土壤)에 있어서는 치환성(置換性) Al의 100% 상당하는 당량(當量)의 중화석회량(中和石灰量) (토양별 소석회량(消石灰量) 범위(範圍)는 45~122kg/10a)으로 대부분의 Al이 중화(中和)되어 Al 중화비율(中和比率)은 평균(平均)95% 이었으나 화산회토양(火山灰土壤)에서는 200%의 중화석회량(中和石灰量)으로도 치환성(置換性) Al이 66.5% 만이 중화(中和)되어 더욱 많은 량(量)(100% 중화량(中和量)외 약(約) 3 배(倍))의 석회(石灰)를 요구(要究)하였다. 3. 광질토양(鑛質土壤)에서는 95%의 치환성(置換性) Al이 중화(中和)되었을 때 평균(平均) pH는 5.2에서 6.3으로 높아졌으며 화산회토양(火山灰土壤)에서는 치환성(置換性) Al의 200% 중화석회량가용(中和石灰量加用)으로 pH는 5.3에서 5.5로 변화(變化)되었을 뿐이었다. 4. 치환성(置換性) Al과 치환산도(置換酸度)($y_1$)의 두 측정치(測定値)(me 단위(單位)) 간(間)에는 r=0.99로서 고도(高度)의 상관관계(相關關係)가 있었으므로 치환산도(置換酸度)는 주로 치환성(置換性) Al에 기인(起因)된 것이라는 사실(事實)을 확인(確認)하였다. 5. 야산지토양(野山地土壤)인 송정통(松亭統) 표토(表土)에 콩을 재배(栽培)한 Pot시험(試驗)에서 인산흡수계수(燐酸吸收係數)의 5% 상당(相當)의 인산(燐酸)(32.1kg/10a)을 중과석(重過石)과 용성인비(熔成燐肥)로 시용(施用)했을 때 치환산도(置換酸度)를 기준한 최적석회소요량(最適石灰所要量)(me) 산출(算出)을 위(爲)한 Liming factor는 중과석(重過石) 1.132, 용성인비(熔成燐肥) 0.594이었고 작물생육(作物生育)을 위한 최적(最適) pH는 6.0 부근이었으며 최적(最適) Al의 중화비율(中和比率)은 80~90% 이었음을 보여 주었다.

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Li-Al-Si 함유 유리세라믹 순환자원으로부터 Ca계열 염배소법 및 이에 따른 수침출 공정에 의한 리튬의 회수 연구 (A Study on the Recovery of Lithium from Secondary Resources of Ceramic Glass Containing Li-Al-Si by Ca-based Salt Roasting and Water Leaching Process)

  • 주성호;신동주;이동석;신선명
    • 자원리싸이클링
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    • 제32권1호
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    • pp.42-49
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    • 2023
  • Li-Al-Si를 함유한 유리세라믹 순환자원은 인덕션, 방화유리, 비젼냄비 등 리튬의 전체 소비량 중 14%로 리튬이온전지 다음으로 많이 쓰인다. 따라서 리튬의 수요가 폭발하고 있는 현재 새로운 리튬 자원을 찾아야 하고 이로부터 리튬의 회수 연구가 필요하다. 본 연구는 이러한 맥락하에 Li을 함유한 새로운 순환자원인 Li-Al-Si 유리세라믹으로부터 리튬을 회수하기 위한 연구를 수행하였다. 본 연구에서는 1.5% Li, 9.4% Al, 28.9% Si를 함유한 Li-Al-Si 유리세라믹 중 방화유리를 원료물질로 사용하였다. 방화유리로부터 리튬을 회수하기 위한 공정은 크게 칼슘 염을 투입한 건식 배소 공정과 수침출 공정으로 나뉜다. 325 mesh 이하로 분쇄된 방화유리 시료를 열처리 전과 열처리 후 칼슘 염을 투입하여 침출 실험을 비교 진행하였고 칼슘 염과 Li-Al-Si 유리세라의 투입비율에 따른 침출율, 칼슘 염 배소 온도에 따른 침출 연구도 비교 수행하였다. 수침출 연구에서는 온도, 시간, 고액비, 그리고 연속 침출횟수에 따라 리튬의 침출율 및 회수율을 비교하였다. 그 결과 Li-Al-Si를 함유한 유리세라믹 방화유리는 열처리를 반드시 수행하여 베타 형태의 스포듀민으로 상변화 시켜야 하며 이로부터 CaCO3 염을 Li-Al-Si를 함유한 유리세라믹 방화유리와 6:1의 비율로 투입하여 1000℃이상에서 배소한 후 4회 이상 연속 침출하여 리튬의 회수율을 98% 이상 획득하였고 이때 리튬의 농도는 200mg/L였다.

용사법에 의해 제조된 $Al/Al_2O_3$ 복합재료의 상대재에 따른 마모특성 (Wear Properties of Thermal Sprayed Al-based Metal Matrix Composites Against Different Counterparts)

  • 김균택;김영식
    • 동력기계공학회지
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    • 제12권3호
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    • pp.60-65
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    • 2008
  • This study aims at investigating the wear properties of thermally sprayed $Al/Al_2O_3$ metal matrix composite(MMC) coating against different counterparts. $Al/Al_2O_3$ MMC coatings were fabricated using a flame spray system on an Al 6061 substrate. Dry sliding wear tests were performed using the sliding speeds of 0.2m/s and the applied loads of 1 and 2 N. AISI 52100, $Al_2O_3$, $Si_3N_4\;and\;ZrO_2$ balls(diameter: 8mm) were used as counterpart materials. Wear properties of $Al/Al_2O_3$ MMC coatings were analyzed using a scanning electron microscope(SEM) and energy dispersive X-ray spectroscopy (EDX). It was revealed that wear properties of $Al/Al_2O_3$ composite coatings were much influenced by counterpart materials. In the case of AISI 52100 used as counterparts, the wear rate of composites coating layer increased according to the increase of the applied load. On the contrary, in the case of ceramics used as counterparts, the wear rate of composites coating layer decreased according to the increase of the applied load.

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