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行政院國家科學委員會專題研究計畫 成果報告

二硫化鉬/金固體潤滑膜之磨潤特性研究 研究成果報告(精簡版)

計 畫 類 別 : 個別型

計 畫 編 號 : NSC 99-2221-E-216-004-

執 行 期 間 : 99 年 08 月 01 日至 100 年 09 月 30 日 執 行 單 位 : 中華大學機械與航太工程研究所

計 畫 主 持 人 : 簡錫新 共 同 主 持 人 : 馬廣仁

計畫參與人員: 碩士班研究生-兼任助理人員:吳崧銓 碩士班研究生-兼任助理人員:劉時瑞

報 告 附 件 : 國外研究心得報告

公 開 資 訊 : 本計畫可公開查詢

中 華 民 國 100 年 12 月 26 日

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中 文 摘 要 : 本研究將嘗試在二硫化鉬薄膜上鍍很薄的金膜層(約 80 nm) 來更進一步增進二硫化鉬薄膜之使用其壽命。研究結果顯示 很薄的金膜在最外層,做磨耗試驗時應力傳遞到二硫化鉬膜 層,使得非晶態二硫化鉬轉變為層狀二硫化鉬,因此具有極 低的摩擦係數,因為金的存在可改善二硫化鉬氧化現象,因 此長時間的磨耗試驗仍可使二硫化鉬/金複合膜層維持很低的 摩擦係數,二硫化鉬之使用壽命也因此大幅提升。氮化鈦硬 膜上施鍍軟的固體潤滑膜時有助於增進二硫化鉬合基材的結 合力,因此氮化鈦/二硫化鉬/金複合膜層之使用壽命可進一 步獲得改善。

中文關鍵詞: 二硫化鉬、金、氮化鈦、固體潤滑膜、磨潤性質

英 文 摘 要 : This study aims to enhance the endurance of MoS2 coating by applying a thin layer of Au (∼0 nm) on MoS2 surface. Experimental results show that the addition of Au film increases the endurance of MoS2/Au over equivalent coatings without Au. The friction coefficient rapidly decreases to a stable value (μ∼.045) after about 100 cycles sliding. After more than 15,000 cycles, the friction coefficient gradually increased to a second stable value (μ

∼.15). An average endurance of over 50,000 cycles was measured in this case. The Au or Au–MoS2 composite layer can effectively prevent oxygen or moisture reaction with MoS2 and hence significantly increases the wear life.

英文關鍵詞:

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1

行政院國家科學委員會補助專題研究計畫 ■成果報告

□期中進度報告

二硫化鉬/金固體潤滑膜之磨潤特性研究

計畫類別: ■ 個別型計畫 □整合型計畫 計畫編號: NSC 99-2221-E-216-004

執行期間:99 年 08 月 01 日至 100 年 09 月 30 日 執行機構及系所: 中華大學機械工程學系

計畫主持人: 簡錫新 共同主持人: 馬廣仁

計畫參與人員: 吳崧銓、劉時瑞

成果報告類型(依經費核定清單規定繳交): ■ 精簡報告 □完整報告

本計畫除繳交成果報告外,另須繳交以下出國心得報告:

□赴國外出差或研習心得報告

□赴大陸地區出差或研習心得報告

■ 出席國際學術會議心得報告

□國際合作研究計畫國外研究報告

處理方式:除列管計畫及下列情形者外,得立即公開查詢 □涉及專利或其他智慧財產權,□一年□二年後可公開 查詢

中 華 民 國 100 年 10 月 31 日

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行政院國家科學委員會專題研究計畫成果報告 二硫化鉬/金固體潤滑膜之磨潤特性研究

The Study of Tribological Properties of MoS2/Au Solid Lubricant Coatings 計畫編號: NSC 99-2221-E-216-004

執行期限:99 年 08 月 01 日至 100 年 09 月 30 日 主持人:簡錫新 中華大學機械系

共同主持人:馬廣仁 中華大學機械系

計畫參與人員:吳崧銓、劉時瑞 中華大學機械系

摘要

本研究將嘗試在二硫化鉬薄膜上鍍很薄 的金膜層(約 80 nm)來增進二硫化鉬薄膜 之使用其壽命。研究結果顯示很薄的金膜 在最外層,做磨耗試驗時觀察經過 100 道 次的迴轉磨耗測試後,摩擦係數開始降低 最後降低到一個穩定植(μ=0.045),經過 15000 道次的迴轉磨耗測試後,摩擦係數 開始上升至第二個穩定植(μ=0.15)。膜層 的壽命超過 50000 道次。證明金膜層或二 硫化鉬/金複合膜層能有效防止了氧氣或 濕氣與二硫化鉬發生反映,因此使二硫化 鉬之使用壽命也因此大幅提升。

關鍵字:二硫化鉬、金、氮化鈦、固體潤 滑膜、磨潤性質

Abstract

This study aims to enhance the endurance of

MoS

2

coating by applying a thin layer of Au (∼80 nm) on MoS

2

surface. Experimental results show that the addition of Au film increases the endurance of MoS

2

/Au over equivalent coatings without Au. The friction coefficient rapidly decreases to a stable value (μ∼= 0.045) after about 100 cycles sliding. After more than 15,000 cycles, the friction coefficient gradually increased to a second stable value (μ∼= 0.15). An average endurance of over 50,000 cycles was measured in this case. The Au or Au–MoS

2

composite layer can effectively prevent oxygen or moisture reaction with MoS

2

and hence significantly increases the wear life.

一 背景說明

MoS2固體潤滑膜的發展已逾 50 年,其在 真空環境(如太空中)的潤滑扮演著無可取 代的地位。MoS2 的潤滑機構中已有許多 的研究報導,一般相信基面(Base plane)上

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3

的 S 與 Mo 呈共價鍵結合,但層與層間則 是以微弱的凡得瓦爾力結合;所以受剪力 時 MoS2很容易沿著基面間滑動,導致低 摩擦係數 [1-3]。

MoS2 固體潤滑膜最大的隱憂是其潤滑性 質對溼氣或氧氣氛十分敏感。通常氧原子 易擴散進入 MoS2,層與層的間隙易生成 MoOx,此一氧化反應破壞了原本層與層 間微弱的凡得瓦爾力鍵結,導致喪失潤滑 效果。一般在真空下,摩擦係數可達 0.01;

但當相對溼度超過 50%時,摩擦係數可能 高達 0.1,磨損壽命也隨著迅速降低 [3-6]。

有鑑於此,此類薄膜常被限制於真空或者 是相對濕度較低的氣氛下使用以確保其 薄膜特性的應用。現今已經有許多產業逐 漸重視這方面的問題,為此投入大量的研 究成本,試圖拓展此系列固體潤滑膜之環 境適應性來取代傳統思維的潤滑機制。

1980 年代濺鍍技術開始應用於沈積 MoS2 薄膜,雖然與基材間的結合力改善 了,但緻密性仍然不理想。一直到了 1990 年代,磁控濺鍍技術發展後,由於離子電 流密度及能量的提高,已使得 MoS2薄膜 的緻密性大為改善 [7,8]。Donnet 等人[8]

在超真空下濺鍍沈積 MoS2薄膜並在高真 空下測得摩擦係數可低至 0.001,也證明 了超真空下有利 MoS2薄膜成長時基面平 行於基材成長,因而有助於超低的摩擦係 數。但是極高真空的濺鍍設備十分昂貴及 耗時甚長,並不符合經濟效益。近來許多 人嘗試在濺鍍 MoS2的同時滲入金屬元素,

以增進摩擦磨損性能(可由製作 MoS2-金 屬複合物靶材或同時濺鍍金屬與 MoS2靶 材達到目的)。

與 一 般 MoS2 固 體 潤 滑 薄 膜 相 較 下 , MoS2-Ti (MoST)硬度高、抗磨耗性佳而且 對於大氣環境的適應性明顯優於 MoS2膜 層,因此 MoS2-Ti (MoST)薄膜其良好的磨 潤成效為相關產業界提供了更寬廣的應 用[9]。近三年來已有相關報導證實二硫化 鉬薄膜已成功的應用在各種刀具、模具及 引擎上,此一結果使得 MoS2薄膜的應用 邁入新的里程(使用環境不再受限於高真 空或開放環境)。

一般相信添加合金元素,可抑制鉬與氧發 生氧化反應;另一可能的原因是金屬元素 有利生成組識較緻密且基面平行基材的 MoS2 薄膜,因此降低了氧的擴散機會;

然而真實的高濕度下低摩擦機構仍待進 一步的釐清。本研究提出在二硫化鉬薄膜 上鍍很薄的金膜層(約 80 nm)來改善 MoS2 薄膜之使用壽命,並探討其磨潤機制。

二 研究方法

本研究將以直流濺射法製作 MoS2薄膜並 尋求最佳之製程參數以利探討其磨潤性 質。除此之外,探討 Au 薄膜鍍於 MoS2 薄膜表面對其磨潤性質所產生的影響。薄 膜磨潤性質的測試則以 pin-on-disc 的方式 進行,並經由側向力的量測獲得其摩擦係 數。MoS2 薄膜顯微組織及磨耗機制將藉 由X光線繞射儀高解析掃描式電子顯微

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鏡分析探討。

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三 結果與討論 微結構及機械性質

以磁控濺鍍法產生之 MoS2薄膜呈現緻 密的柱狀組織,X 光結構分析呈現非晶 態或奈米結晶特性(圖一)。二硫化鉬薄 膜上鍍很薄的金膜層(約 80 nm)來增進 二硫化鉬薄膜之使用其壽命。Mo:S 的 化 學 組 成 比 和 製 程 參 數 有 關 , 約 為 1.4-1.6。微量的氧(<5%)被偵測到在 鍍膜時摻雜進入 MoS2膜層。以奈米壓 痕器測得 MoS2膜層的硬度為 5.20 GPa,

彈性摩數為 102 GPa,顯示其硬度遠高 於 傳 統 的 MoS2 膜 層 。 MoS2 以 及 MoS2/Au 膜層與基材的黏著強度超過 80 牛頓。圖二顯示在做硬度測試時層 狀的結構非常容易在 MoS2/Au 膜層上 方生成。MoS2膜層具有高硬度可歸因 於其具有緻密的顯微組織。在刮痕及磨 耗實驗測試時非晶態結構的 MoS2膜層 有很大的傾向生成層狀的結構。

磨潤性質

圖三比較添加了金膜在 MoS2表面經過 磨耗試驗後的結果。純的 MoS2膜層具 有很低的磨擦係數(μ=0.03)。然而,

在經過了 9000 道次的迴轉磨耗測試後 膜層失效,我們相信在剛開始測試時 MoS2膜層生成層狀的結構使其具有低 的摩擦係數,接著氧滲入層狀的 MoS2 膜層之間並發生氧化反應使其失效,在

MoS2/Au 的雙層膜系統,摩擦係數起初 接觸時很高(μ=0.15),顯示此時較高 的磨擦係數主要由 Au 膜所主導,塑性 流動主要發生在金膜層。重複的滑動使 得金堆積在磨痕兩側使金膜層變簡薄。

經過 100 道次的迴轉磨耗測試後,當剪 應力滲透 MoS2膜層並超過 MoS2的剪 力強度時,MoS2膜層開始參與塑性流 動過程,因此摩擦係數開始降低並達到 一個穩定植(μ=0.045)。繼續滑動使得 金膜和 MoS2膜層形成很薄的 Au/MoS2 複合膜層。Au/MoS2膜層有時會脫落並 轉移至對面的磨球上,並黏附在底下的 層狀 MoS2的表面或破裂面的間隙內上,

因此可有效的延遲氧和 MoS2的反應。

在這個階段塑性流動同時發生在 MoS2 膜層以及 Au/MoS2複合膜層之間,因 此摩擦係數或能量的損失較低,趨近如 純的 MoS2膜層。其關鍵在於 Au 膜不 能太厚,這個結果和其他研究者做出來 的結果有很大的不同,這也解釋了為何 其他學者做出的結果摩擦係數較高的 原因。研究也發現增加所施加的負荷,

會有利於塑性流動較快的發生在 MoS2 膜層,因此可有利於降低摩擦係數。

經過 15000 道次的滑動後整個 MoS2膜 層和金結合成 Au/MoS2複合層,塑性 流動主要發生在 Au/MoS2複合膜層間,

因此摩擦係數又升高到第二個穩定植,

金的含量在經過 15000 道次的磨損後 濃度為 10.30wt%,氧的濃度也隨著時

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間而增加。相信 Au 或 Au/MoS2複合膜 層可有效的延遲氧或溼氣與 MoS2膜層 反應因此大大的增加了膜層的磨耗壽 命,經過了 50000 道次的磨損試驗後,

摩擦係數還能維持在 0.15,因此評估磨 層 的 使 用 壽 命 超 過 50000 道 次 。 當減低金膜層厚度至 30 奈米可獲致較 低的磨擦係數(0.04),但低磨擦係數 只能夠維持到 11000 道次,摩擦係數就 增加到較高的值(0.14-0.15)。估計的 磨層使用壽命僅能達到 38000 道次。

圖一 以非平衡磁控濺鍍設備製作出 MoS2/Au 膜層之顯微組織。

圖 二 顯 示 在 做 硬 度 測 試 後 , 在 MoS2/Au 膜層上方生成層狀的

結構(荷重 300g) 。

圖三 比較 MoS2 及 MoS2/Au 膜層之磨 擦係數隨時間變化情形。

圖五 做磨耗試驗時應力傳遞到二硫化 鉬膜層促使 MoS2 與 Au 在介面 生成 MoS2-Au 複合膜層。

本研究中為進一步改善 MoS2固體潤滑 膜與基材的黏著強度,將先以磁控濺鍍

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7

法在工具鋼基材上施鍍 TiN 膜層,籍 由製程參數之控制,使其表面具有較疏 鬆之柱狀晶結構,接續再共鍍 TiN 及 MoS2-Ti (MoST) 膜 形 成 漸 進 層 , 使 MoST 有機會在成膜時滲入 TiN 之柱狀 晶粒之間,以增進 TiN 薄膜與 MoST 膜之間之結合強度,接續鍍 MoST 膜 層,以利低摩擦係數 (圖六、七)。TiN 之柱狀晶結構有較有利於擄獲 MoST 的或 MoST-Au 磨屑,延續其潤滑功能。

Au 膜層最後鍍在 MoST 的表面形成 TiN/MoST/Au 多層結構可改善氧化現 象,以增進使用壽命 (圖八)。

圖六 TiN/MoST/Au 多層結構示意圖。

圖七 TiN/MoST/Au 多層結構顯織。

圖八 比較不同膜層之使用壽命。

四 結論

很薄的金膜在最外層,做磨耗試驗 時應力傳遞到二硫化鉬膜層,使得非晶 態二硫化鉬轉變為層狀二硫化鉬,因此 具有極低的摩擦係數,因為金的存在可 改善二硫化鉬氧化現象,因此長時間的 磨耗試驗仍可使二硫化鉬/金複合膜層 維持很低的摩擦係數,二硫化鉬之使用 壽命也因此大幅提升。

五 參考文獻

1. J. C. Tyler and P. M. Ku, “Fundamental Investigation of Molybdenum Disulfide As a Solid Lubricant”, Final Technical Report, Contract No. w 66-0495-d, Naval Air Systems, Command, Washington, D.C., 1967.

2. J. T.cuum Spalvins, Vacuum Sci.

Technol. A., vol. 5( 2), p. 212-219, 1987

3. E. F. Finkin, “Theory for the Friction of Sulfide and Other Thin Films”, Wear, vol. 18, p. 231, 1971.

4. I. L. Singer, “Solid Lubrication

0 20000 40000 60000

TiN MoS2 TiN/MoS2 MoS2/AuTiN/MoS2/Au

No. of cycles to failure

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Process”, Fundamental of Friction:

Macroscopic and Microscopic Process, Singer, I. L and Pollock, H.

M. (Eds), Kluwer, 1992.

5. E. W. Robert and W. B. Price, “An Vacuum, Tribological Properties of High Rate Sputtered MoS2 Applied to Metal and Ceramic Substrates”, New Materials Approaches to Tribology: Theory and Applications, Pope, L., Fehrenbacher, L. and Winer, W. (Eds), MRS Symposium, vol. 140, p. 251, 1989.

6. T. Spalvins, “Rreview of Recent Advances in Solid Film Lubrication”, J. Vac. Sci. Technol., vol. A5(2), p.

212, 1987.

7. K. J. Ma, A. Bloyce, K. Mao., T. Bell and D. G. Teer, “Friction and Wear Behaviour of TiN/Au, TiN/MoS2, and TiN/TiCN/DLC Coatings”, Presented at ICMCTF, 1996.

8. C. Donnet, M. Belin, T. LeMogne and J. M. Martin, “Tribological Behaviour of Solid Lubricated Contacts in Air and High-Vacuum Environment”, The Third Body Concept, Dowson, D. et al (Eds), Elsevier, p. 389, 1996.

9.

N. M. Renevier, V. C. Fox, D. G.

Teer, J. Hampshire, “

Performance of low friction MoS2 titanium composite coatings used in forming applications

”,

Materials and Design, vol. 21, p. 337-343, 2000.

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出席國際學術會議心得報告 I

計畫編號 NSC 99-2221-E-216-004

計畫名稱 二硫化鉬/金固體潤滑膜之磨潤特性研究

出國人員姓名

服務機關及職稱 馬廣仁 中華大學機械系副教授 會議時間地點 May 28-30, 2011, Changsha, China

會議名稱 2011 International Conference on Chemical Engineering and Advanced Materials

發表論文題目 Microstructure and Mechanical Properties of Air Core Polymer Photonic Crystal Fibers

一、參加會議經過

1. 國際化學及尖端材料工程會議主題涵蓋範圍很廣,主要有基礎化學工程、化學工程的應用及尖 端材料工程三大部分。基礎化學工程部分有許多發表重點都在奈米複合材料的合成,包括碳纖 維及無機氧化物纖維複材之製程及其性質探討等,少數文章討論環境及金屬回收之化工製程,

議題較雜。化學工程的應用部分大部分著重能源、生醫及環境之應用,少數文章探討了鋁合金 及銅合金之化學表面處理技術在 3C 產品之應用也受到廣大的迴響。尖端材料工程的議題很廣,

較受注意的題目則在燃料電池材料及新型薄膜太陽能電池材料。有機薄膜太陽能電池材料雖然 效能仍嫌不足,但製程較簡單且價格低廉,極有可能最後勝出。

2. 國際化學及尖端材料工程會議十分盛大,共有兩百多人與會,許多是世界知名學者,中國科學 院相關領域的院士有兩位與會。作者發表之論文有關光子晶體光纖之製作及機械性質研究,係 本計畫延伸出的結果,由於極具生醫及環境感測應用潛力,會後有許多學者詢問相關技術。目 前中國大陸也有學者進行光子晶體光纖製作相關研究,但都同樣受限在資源不足,無法製作出 高品質之光子晶體光纖,其他相關的光纖藕合問題也亟待解決。

二、與會心得

今年參加之會議都有意外之收獲,由於會議主題較廣,也較有工業應用價值,聽眾提的問題 提供了不同的思考方向,對未來研究方向有極大的幫助。大會安排之參觀活動十分精采,也藉此 機會認識相關之學者及膫解其研究能量。由於會議主題太廣,較無法聚焦,對於議題深度之探討 較嫌不足。

三、考察參觀活動(無是項活動者略) 四、建議

五、攜回資料名稱及內容 1.研討會參考資料 六、其他

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College of Engineering, Chung Hua University, No. 707, Sec. 2, Wu Fu Rd., Hsin Chu, Taiwan

Department of Mechanical Engineering, Chung Hua University, No. 707, Sec. 2, Wu Fu Rd., Hsin

Department of Mechanical and Electro-Mechanical Engineering, Tam-Kang University, No.151

hhchien@chu.edu.tw, ma600229@ms17.hinet.net, ivu639@yam.com, clchao@mail.tku.edu.tw

Microstructure and Mechanical Properties of Air Core Polymer Photonic Crystal Fibers

Hsi-Hsin Chien

1,2,a

, Kung-Jeng Ma

1,2,b

, Yun-Peng Yeh

1,c

, and Choung-Lii Chao

3d

1

30067.

2

Chu, Taiwan 30067.

3

Ying-Chuan Road, Tamsui, Taipei Hsien, Taiwan 251.

a b c d

Keywords: PMMA, air core, photonic crystal fibers, mechanical properties

Abstract. Polymer based photonic crystal fibers with low cost manufacturability, and the mechanical

and chemical flexibility offer key advantages over traditional silica based photonic crystal fibers.

PMMA photonic crystal fiber was fabricated by stacking an array of PMMA capillaries to form a preform, and followed by fusing and drawing into fiber with a draw tower. The air hole diameter and fraction of photonic crystal fiber can be manipulated by the thickness of PMMA capillaries and drawing temperature. The measurement of mechanical properties was performed by universal testing machine. The air core guiding phenomena was observed in air-core PMMA photonic crystal fiber.

The ultimate tensile strength of PMMA photonic crystal fiber increases with the increase of the air-hole fraction. The mechanical strengths of all the microstructured optical fibers are higher than those of traditional PMMA fibers. This can be attributed to the introduction of more cellular interfaces which hinder the crack propagation and hence improve the mechanical strength. The plastic extension of PMMA microstructured optical fiber decreases with the increase of the air-hole fraction. Overall, the mechanical flexibility of PMMA microstructured optical fiber is superior than that of traditional PMMA optical fibers.

Introduction

The silica-based air-guided photonic bandgap fibers have been developed recently [1-5]. The potential benefits of guiding light in air derive from lower Rayleigh scattering, lower nonlinearity and lower transmission loss compared to conventional waveguides. The polymer-based photonic bandgap fibers with low-cost manufacturability and the mechanical flexibility offer key advantages over conventional silica based photonic bandgap fibers. However, the fabrication of polymer photonic band gap fibers is more complicated due to the existence of severe water absorption, shrinkage, and poor thermal

conductivities of polymer materials. Recently, solid core polymer PCFs, which are generally called microstructured optical polymer fibers (MPOFs), have been fabricated and studied [6]. However, the fabrication of air-guided polymer PCFs are still unsuccessful. The studies regarding their mechanical properties of polymer based PCF are still lacking.

In this work, we report the investigations of the parameters that are critical in the fabrication

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Experimental

The fabrication processes of the air core polymer PCFs preform are illustrated in Figure 1. Hollow PMMA tubes (n~1.492) with 10 mm outer diameter and 8 mm inner diameter were first stacked into a hexagonal array. Some hollow tube(s) was/were removed at center site(s) in order to form the air core.

The stacked tubes were annealed at 110 °C for 3 hours for water removal and then heated to form the preform. The drawing of the air-guided polymer PCFs is a two-step process. During the first step, the preform was drawn at an elevated temperature into a smaller preform with 40 cm in length and 10 mm in diameter. This smaller preform was then drawn again into a fiber with a diameter between 125 and 300 μm depending on the drawing temperature and speed. The drawing speed is controlled under 10 cm/min. From the stacked tubes to a fiber, the overall scale of the structure is reduced by a factor of 300, while the structure formed in the preform stage is still maintained. The measurement of

mechanical properties was performed by universal testing machine. The loading foce is less than 5 kg and the loading speed is set at 5.2 mm/min. The resolution of the load cell approaches 0.5%.

(a) (b) (c)

Figure 1. Fabrication processes of MPOFs. (a) step 1: cutting PMMA tubes; (b) step 2: packing and thermal annealing; (c) step 3: drawing into preform.

Results and Discussion

The furnace temperature affects the formation of the air-guided polymer PCFs preforms. Uneven temperature distribution results in structure distortion or irregular hole diameters (Figure 2). The diameters of the air holes at the perimeter are smaller than those of the air holes near the center, which can be attributed to the significant thermal insulating effect in the polymer PCFs preform. The

periphery of the preform will reach drawing temperature before the center does. Higher temperature leads to higher surface tension and thus larger air hole shrinkage. The larger the MPOF preform, the longer time is needed to achieve uniform temperature distribution over the whole sample. In fact, the diffusion treatment can be used to control the air hole diameter and air filling fraction.

Figure 2. Drawing without enough diffusion treatment leads to irregular hole diameters.

The holding and fastening methods are also critical for the fabrication of high quality PCFs. The

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holes structure has to be kept without block in order to remain gas flow and temperature distribution under steady state. The blocking in the air core during the drawing process will result in the

expansion and distortion of the air core, as shown in Figure 3.

Figure 3. Drawing with block in the air core on the top of the PCFs perform results in the expansion and distortion of the air core.

The effects of drawing temperature were studied in detail. Drawing at temperature of 150°C leads to the air-cored PCFs with air fraction higher than 80%, as shown in Figure 4(a). At the drawing temperature between 165 to 175°C, the ratio of the air hole diameter d to the pitch between the holes remains almost the same. The small triangular air holes in the figures are the air gaps formed at corners of the stacked capillaries. The diameter d is in the range between 8 and 10μm, the pitch is between 12 and 14 μm, and the fraction of air present in the samples is up to around 48% (Figure 4(b)).

By increasing the furnace temperature to over 175°C, the triangular interstitial air holes become circular holes and the size of those holes is also reduced (Figure 4(c)). The maximum attainable air filling fraction is limited by the effect of surface tension. With this limitation, it is difficult to fabricate large air fraction samples with the small pitches.

Figure 4 SEM images of the cleaved end-face of the MPOFs drawn at various temperature (a) 155°C (b) 175°C (c) 195°C.

The optical tests showed that air core PMMA photonic crystal fiber could well guide optical signals at wavelength of 632.8 nm. with air fraction above 48% (Figure 5). However the air-guiding phenomena disappears after 2 months possibly due to the absorption problems.

Figure 5. Measurement results of the MPOF samples. The air core PMMA photonic crystal fiber

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Yield Strength ( MPa ) Plastic Extension

( oC)

The yield strength and ultimate tensile strength and of air cored PMMA PCFs increases with the decrease of the drawing temperature (or with the increase of the air-hole fraction), as shown in Figure 6. The mechanical strengths of all the air cored PMMA PCFs are higher than those of traditional PMMA fibers. This can be attributed to the introduction of more cellular interfaces which hinder the crack propagation and hence improve the mechanical strength. The plastic extension of PMMA microstructured optical fiber decreases with the increase of the air-hole fraction, as shown in Figure 7.

It is believed that the wall thickness of PMMA is helpful for the plastic extension of PCFs. It can be observed that the plastic extension of all the polymer PCFs is over 100%, which is higher than that of traditional PMMA fibers. It is interesting to note that the fractured surface demonstrates 45 cleavage facet rather than traditional ductile fractured surface (Figure 8). Further studies are needed for the investigation of the deformation and fracture mechanisms of polymer PCFs. Overall, the mechanical flexibility of PMMA air cored PCFs is superior than that of traditional PMMA optical fiber. This conclusion agrees with the results observed in cellular structured materials. The natural cellular structure such as woods, provides excellent deformation and energy adsorption capabilities [7]. The fabrication of polymer based PCFs provides a new route for the fabrication of biomimetic cellular materials and smart biosensors.

Air fraction in PCFs

Figure 6. The influence of drawing temperature on the yield strength of air core polymer photonic crystal fibers.

Plastic Extension

Max. Tensile Strength ( MPa )

Drawing Temperature

Figure 7. The influence of drawing temperature on the plastic extension of air core polymer photonic crystal fibers.

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Figure 8. SEM image of fractured surface of polymer PCFs after tensile tests.

Summary

The air core guiding phenomena was observed in air-core PMMA photonic crystal fiber with air fraction above 48%. The ultimate tensile strength of PMMA photonic crystal fiber increases with the increase of the air-hole fraction. The mechanical strengths of all the microstructured optical fibers are higher than those of traditional PMMA fibers. This can be attributed to the introduction of more cellular interfaces which hinder the crack propagation and hence improve the mechanical strength.

The plastic extension of PMMA microstructured optical fiber decreases with the increase of the air-hole fraction.

Acknowledgements

This research was supported by the National Science Council, The Republic of China, under Grant No.

NSC 98-2221-E-216-010.

References

[1] J.C. Knight, J. Broeng, T. A. Birks and P.St.J. Russell: Science Vol. 282, (1998), p. 1476.

[2] R.F. Cregan, B. J. Mangan, J.C. Knight, T.A. Birks, P. St. J.Russell, P. J. Roberts, D. C. Allan:

Science Vol. 285 (1999), p 1537.

[3] T.M. Monro, D.J. Richardson and P.J. Bennett: J. Lightwave Technol. Vol.17(6), (1999), p.1093.

[4] B. Temelkuran, S.D. Hart, G. Benoit, J.D. Joannopoulos and Y. Fink: Nature 420 (2002), p. 652.

[5] S.D. Hart, G.R. Maskaly, B.Temelkuran, P.H. Prideaux, J.D. Joannopoulos, and Y. Fink: Science, Vol. 296 (2002), p. 510.

[6] M.A. van Eijkelenborg, M.C. J. Large, A. Argyros, J. Zagari, S. Manos, N. A. Issa1, I. Bassett1, S.

Fleming, R. C. McPhedran, C. de Sterke and N.A.P. Nicorovici: Optics Express Vol. 9 (2001), p.

319.

[7] L.J. Gibson andM.F. Ashby: Cellular Solids: Structure and Properties (Cambridge University Press U.K. 1999).

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出席國際學術會議心得報告 II

計畫編號 NSC 99-2221-E-216-004

計畫名稱 二硫化鉬/金固體潤滑膜之研究

出國人員姓名

服務機關及職稱 馬廣仁 中華大學機械系副教授

會議時間地點 August 12 - 14, 2011 中國-哈爾濱

會議名稱 2011 International Conference on Electronic & Mechanical Engineering and Information Technology

發表論文題目 Kinetic Study of Bacterial Adhesion on Biomaterials by Using Optical Waveguide Lightmode Spectroscopy

一、參加會議經過

此會議名稱為 IEEE 機電工程與資訊技術國際會議,會議地點設在哈爾濱理工大學。會議 涵蓋的主題很廣,包含機電工程、機械設計製造及其自動化、先進材料與先進製造技術、機 電工程、電腦軟體工程與資訊系統設計、電腦模擬與建模、電腦控制技術、計算科學及人工 智慧等幾個大主題。共計 145 篇論文發表,參加人數逾 300 人。會議安排三個場地進行,並 在會前安排了兩個半天的課程。第一天上午是由五位 IEEE 的 fellow 對最近發展較重要的議 題作回顧,下午開始分場地不同主題發表論文。

作者較有興趣之主題為機械設計製造及其自動化,包括很多子題包含機械動力學及其應用、

機械傳動理論及應用技術 、機械可靠性理論與工程、機械系統檢測技術、機械系統故障診斷 與排除技術、摩擦磨損理論及應用、振動、雜訊分析與控制、機械結構動態分析、優化與控 制、熱與熱傳導 、冶金新工藝、新技術、新方法、能源的儲運與開發、礦山機械設計與製造、

新能源裝備製造、雲製造/極端製造、生物製造、現代集成製造技術、工業設計、工程優化、

產品設計與開發、製造過程品質檢測與控制、電腦輔助設計、製造與工程 CAD/CAM/CAE 等。

由發表的論文及聽眾看出來大家對機電整合技術及能源的應用課題較受矚目。新的太陽相關 奈米材料也受到許多重視。大會還安排了廠商產品展示,及哈爾濱理工大學相關系所之研究 成果展示。當然少不了大會安排的晚宴及參觀活動,由晚宴的安排可感受到東北人的熱情。

二、與會心得

大會安排了 keynote 講者及題目都是目前相關領域的一時之選,因此提問及討論都十分 踴躍,由 keynote 演講內容很快的可以掌握目前該領域技術發展方向及困境。雖然個人對資 訊及電腦運算主題不熟悉,但在講者的深入淺出的引導下也能很快進入狀況。個人較有興趣 的題目是奈米材料及精密技術,也很幸運的聽到許多新的課題,對個人以後研發方向有許多 啟發。此次會議我們發表之文章和生物感測及材料表面親疏水結構有關,未來可應用在生醫 及民生產品,因此有許多學者主動和我們接觸,瞭解該技術之優勢及瓶頸。

三、考察參觀活動(無是項活動者略) 四、建議

哈爾濱一直是中國重工業發展重鎮,產學合作密切,此次會議也有機會認識幾位哈工大 之教授,能充分了解哈爾濱機械產業發展方向及感受到哈爾濱傳統機械產業面臨轉型的壓 力。由於本校已和哈爾濱理工學院互結姊妹校,此行所有教師都受到特別接待,盛情可感。

我們也邀請機械學院的教師來本校參觀,並希望促成更多的學生來本校進行交換學生,做更 多的學術交流。

五、攜回資料名稱及內容 1.研討會參考資料 六、其他

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Kinetic Study of Bacterial Adhesion on Biomaterials by Using Optical Waveguide Lightmode Spectroscopy

H.H. Chien

1,a, K.J. Ma1,b, Jeremy J. Ramsden2,c

and Y.P. Yeh

1,2,d

1 College of Engineering, Chung Hua University, HsinChu, Taiwan 300

2 Cranfield University, Cranfield, Bedford, MK43 0AL England

a hhchien@chu.edu.tw, bkjma@chu.edu.tw, cj.ramsden@cranfield.ac.uk, dd09324003@chu.edu.tw

Abstract. The principles of bacterial identification are beginning to be understood at the kinetic level in the past few years, nevertheless, the crucial aspects to be taken into consideration are the spatial arrangements of molecules or atoms at the interacting surfaces and the profiles of the interfacial forces. In this study, the dynamics of attachment and detachment of E.coli K12 to ultra thin film silica and zirconia surfaces with precisely coated by sol-gel method is measured by using optical waveguide lightmode spectroscopy (OWLS) are described.

charge [5], which is not always a sufficiently good discriminator. The technique now widely called optical lightmode waveguide spectroscopy (OWLS) involves measuring the perturbation of the evanescent fields associated with one or more waveguide lightmodes [6]. It is particularly convenient to measure this perturbation with the help of a grating coupler [7], with which light can be coupled in or out of the waveguide. In this study, the adhesion kinetics of E.coli K12 and L.plantarum to SiO2

and ZrO2 are measured by using optical waveguide lightmode spectroscopy (OWLS) are demonstrated.

Keywords: bacterial adhesion, kinetic, optical waveguide lightmode spectroscopy

I. Introduction

Bacterial adhesion to surfaces plays a major role in the transmission of pathogens, the persistent infection of surgical implants etc. There is therefore intense interest in designing surfaces to control (and hence eliminate, if deleterious) adhesion. There are indications that interaction energies determined by average physico-chemical

properties of the bacterial and adsorbing surfaces play a determining rôle in adhesion [1]. The issue of identified bacteria to the unknown transmission of pathogens are important nowadays. Nevertheless, the traditional identification methods of bacteria are complex, expensive and time consuming, typically take 3 to 4 days, therefore, there is an intense interest in speeding up the determination of microbial pathogens. The natural environment of bacteria stay mostly at the interface of solid-liquid or solid-air interface and often freely float bacteria could be the first step of adhesion process, after bacteria arrive the surface, microbes tend to either attach to the surface or detach and return to their environment. Hence, it is crucial to understand bacterial adhesion tendence to surface.

Bacterial adhesion to the surface has been studied in many previous works but many of them were focused on the specific adhesion molecules between bacteria and surface (e.g. Jucker, et al.(1997) [2] and Antonietta Splendiani, Cristiano Nicolella(2006) [3]); some of them were focused on the classification of gene expresion [4]. These

techniques are slow, labor intensive and hence expensive.

A more recent approach has been to use electrophoresis to separate bacteria on the basis of their surface electrostatic

II. Experimental

Optical Waveguide Lightmode Spectroscopy (OWLS) [8-9] is a label free technique for providing a high accuracy kinetic data required with excellent time

resolution. This will enable us to probe hence understand the process involved in bacterial adhesion at nanometric precision. The changes of electronic polarizability in the measuring field of an optical waveguide alter the phase velocity of guided waves. This change can be interpreted as the change of mass and/or shape of adherent bacteria. A grating serves to incouple light into a planar optical waveguide in which the light then propagates, generating an evanescent field. The evanescent field is used to probe the optical properties of the solution in the vicinity of the surface. This method is based on its sensitivity to the changes of the refractive index when deposition of macromolecules occurs. This can be interpreted as the change of mass and/or shape of adherent bacteria.

The typical experimental situation to which the following procedure (see Figure 1) can advantageously be applied begins with a waveguide equilibrated with the medium used to suspend the bacteria, which are then (at time t = 0) flowed in suspension over the waveguide, leading to a gradual increase b(t) in the number of adsorbed bacteria b per unit area until a steady state is reached at which b(t) is constant, with a value of bsat. Usually pure suspending medium is then flowed over the waveguide to verify that the adsorption is irreversible. The quantity b is, to a good approximation, linearly proportional to an effective refractive index N of the waveguide, say the zeroth transverse electric (TE) one [10].

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G123

(z)



a



exp1dz

Figure 1. Typical experimental procedure for the kinetics of bacteria adhesion. Bacteria in PBS buffer solution was pumped through the optical waveguide lightmode spectroscopy by peristaltic pump. The flow rate is 10 μl/s and the temperature.

Bacteria. In this study, Escherichia coli (strain JM83, a K12 derivative) and Lactobacillus plantarum were chosen as they are common nonpathogenic strains and widely used for research, which makes them good

representatives for investigating bacterial adsorption. A live sample of E. coli was cultured in 100 ml Luria broth (LB) overnight for approx. 18 hours at 37℃. L. plantarum was cultured in 100 ml MRS broth overnight at 30℃. Then the following step was the washing, hence, removing the

where ΔG123 is the interfacial free energy, kB is Boltzman constant (1.38x10-23 J/K) and T is absolute temperature.

The energy barrier can be presented by the adsorption rate of constant ka with

traces of the liquid broth, which may interfere with the surface in the adsorption measurement. After supernatant removal, the pellets were resuspended in cold aqueous buffer, either PBS or Z 1150 buffer .

k a

 exp( G

a

k BT ) (3)

Biomaterials. The substrates for the bacterial adhesion in this experiment were biomaterial SiO2 and ZrO2, which was produced by physical vapour deposition (PVD)

where ω is some intrinsic frequency factor and presume energy barrier is to be given by the unit of kBT . And the rate of adsorbed bacteria then can be written as:

within the thickness 10 to 20 nm layer of silica and zirconia on glass weveguides gratings(ASI 2400, made by Microvacuum Ltd., Budapest, Hungary).

db

dt  k a (G123 )cb (4)

Adsorption. The investigation of adsorption kinetics is an extremely powerful and sensitive method for probing the energetic profile in the vicinity of an adsorbing surface.

The kinetics of an interfacial reaction will be determined by the potential barriers experienced by the mobile component (bacteria were assumed to be a sphere of radius r) dissolved in a medium, as it approaches the stationary substrate. Normally, these barriers can be calculated by an adsorption rate coefficient ka, where

where cb is the effective bulk concentration (include hydrodynamic function); b is number of bacteria per unit area; a is area occupied by one bacterium; ф is fraction of available adsorption surface, which is related to the size and shape of bacteria.

The typical experimental situation to which the following procedure can advantageously be applied begins with a waveguide equilibrated with the medium used to suspend the bacteria, which are then (at time t = 0) flowed k a D

a

(1) in suspension over the waveguide, leading to a gradual increase b(t) in the number of adsorbed bacteria b per unit area until a steady state is reached at which b(t) is constant, where D is diffusion coefficient of bacteria and δa is

adsorption distance which was given as [11]:

with a value of bsat [12]. Usually pure suspending medium is then flowed over the waveguide to verify that the adsorption is irreversible.

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Adsorbent SiO2 ZrO2

bsat/µm -2 0.11 0.105

ka/μms -1 0.23 0.46

Measured Interfacial free

-7 -2

energy(10 ) /mJm -6.8 -11.7

a/μm 2 3.22 4.26

Bacteria Material PBS Z1150

E.coli SiO2 3.22 4.06

ZrO2 4.26 2.04

L.plantarum SiO2 1.29 1.37

ZrO2 0.59 2.57

Adsorbent SiO2 ZrO2

bsat/µm -2 0.11 0.105

ka/μms -1 0.23 0.46

Measured Interfacial free

-7 -2

energy(10 ) /mJm -6.8 -11.7

a/μm 2 3.22 4.26

Bacteria Material PBS Z1150

E.coli SiO2 3.22 4.06

ZrO2 4.26 2.04

L.plantarum SiO2 1.29 1.37

ZrO2 0.59 2.57

III. Results and Discussions Figure 2 shows the results from a typical

adsorption/desorption experiment. Adsorption approaches saturation, apparently asymptotically. Upon flooding with PBS buffer solution at the same flow rate, some bacteria were desorbed in this case. Note that the concentration of E.coli cb=1.04x108 cells/ml and the concentration of L.plantarum cb = 4.22x106 cells/ml. bsat is read from the Figure 2 curve where the adsorption of bacteria reaches saturation.

Figure 2. Typical raw OWLS result. Mark 1 indicates that the start of bacterial flow and Mark 2 indicates its end. The tangent shows the kinetic of the adsorption of E.coli K12.

For the adsorption objects to a surface, nevertheless, any kind of surface is mainly a continuum and it is known at once that the saturate surface “jammed” in the sense that there is no space to let objects move in, or there are very a lot of spare spaces but all the spare spaces may not be big enough separately to allow objects get in. For this problem of random sequential adsorption (RSA) to a surface has been noticed for a long time and the simplest process to solve the problem of loading up space by objects deposited

The adsorption results of E.coli on silica(SiO2) and zirconia(ZrO2) were shown in Table 1. Note that ka and a respectively are the kinetic rate coefficient of adsorption and the area occupied by one bacterium and both are derived from fitting Equation (4). The rate of adsorption and the area occupied by one bacterium of ZrO2 are also higher than SiO2. This indicates that ZrO2 has a stronger force to attract E.coli than SiO2. The measured interfacial free energy of E.coli on both surfaces are -6.8x10-7 and -11.7x10-7 mJm-2 respectively.

Table 1 The adsorption results of E.coli K12 on SiO2 and ZrO 2.

Table 2 shows the results of area occupied by one bacterium on both surface in phosphate (PBS) and chloride (Z1150) buffer solutions. Note that zirconia(ZrO2) has less area occupied by L.plantarum, which zirconia(ZrO2) has higher occupied area by E.coli. Also note that the chloride in buffer solution could alter the attachment of bacteria to different surfaces. On the other hand, the dependence on ion type - comparing PBS and Z1150 - on silica(SiO2), the difference is not so great (slightly smaller in PBS for both E.coli and L.plantarum). On zirconia(ZrO2), there is a dramatic difference - E.coli is bigger in PBS, but L.plantarum is smaller.

Table 2 Area occupied by one bacterium(a/µm2) in PBS (phosphate) and Z1150 (chloride).

sequentially at randomly chosen location in a continuous condition is random sequential addition (RSA) [6]. Figure 3 show the fitting results of the kinetics and mass of adsorbed bacteria on the surface. It is clear that a plot is reasonably well fitted by a random sequential adsorption process.

IV. Conclusion

In this study, the adhesion kinetics results of E.coli K12 and L.plantarum to surface SiO2 and ZrO2 in PBS and Z1150 have been demonstrated by optical waveguide lightmode spectroscopy (OWLS). The interaction of two kinds of bacteria, which are gram-positive and gram- negative bacteria, can be well predicted and their interfacial energies are deducible from the adsorption kinetics in the experiment. Furthermore, the rate of adsorption is characterized by the adsorption rate constant Figure 3. The result of the rate of the bacterial adsorption vs the number of

bacteria on the surface with random sequential adsorption fit.

ka, is inversely proportional to the integral of the bacteria substrate interfacial free energy ∆G123.

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Bacterial adsorption is complicated, however bacteria have a characteristic surface chemical signature which could selectively bind to surface. Bacterial adsorption also follows the role of random sequential adsorption, which that means not only should the kinetics follow the characteristic random sequential adsorption law, but if the adsorption is irreversible then a should be irrespective to the surface. Given, however, the experimental difficulties inherent in measurements of the adsorption of a living bacterium, the methodology presented in the work is likely to be adequate for many purposes, which might include further analysis of the adsorption kinetics and demonstrate bacterial and other biomaterials in the future.

References

[1] H. C. van der Mei, B. van de Belt-Gritter, G. Reid, H.

Bialkowska-Hobrzanska, and H. J. Busscher, "Adhesion of

[4] S. Vilain, P. Cosette, M. Hubert, C. Lange, G.-A. Junter, and T.

Jouenne, "Proteomic analysis of agar gel-entrapped Pseudomonas aeruginosa," PROTEOMICS, vol. 4, pp. 1996-2004, 2004.

[5] W. S. Ramsey, E. D. Nowlan, and L. B. Simpson, "Resolution of microbial mixtures by free flow electrophoresis," Applied Microbiology and Biotechnology, vol. 9, pp. 217-226, 1980.

[6] J. J. Ramsden, "Review of new experimental techniques for investigating random sequential adsorption," Journal of Statistical Physics, vol. 73, pp. 853-877, 1993.

[7] K. Tiefenthaler and W. Lukosz, "Sensitivity of grating couplers as integrated-optical chemical sensors," Journal of the Optical Society of America B, vol. 6, pp. 209-220, 1989.

[8] I. Szendro, "Art and practice to emboss gratings into sol-gel waveguides," in Functional Integration of Opto-Electro-Mechanical Devices and Systems, San Jose, CA, USA, 2001, pp. 80-87.

[9] Vörös.J., J. J. Ramsden, G. Csúcs, I. Szendro, S. M. De Paul, M.

Textor, and N. D. Spencer, "Optical grating coupler biosensors,"

Biomaterials, vol. 23, pp. 3699-3710, 2002.

[10] E. K. Mann, "Evaluating Optical Techniques for Determining Film Structure: Optical Invariants for Anisotropic Dielectric Thin Films,"

Langmuir, vol. 17, pp. 5872-5881, 2001.

[11] L. A. Spielman and S. K. Friedlander, "Role of the electrical double coagulase-negative staphylococci grouped according to layer in particle deposition by convective diffusion," Journal of physico-chemical surface properties," Microbiology, vol. 143, pp.

3861-3870, December 1, 1997 1997.

[2] B. A. Jucker, H. Harms, S. J. Hug, and A. J. B. Zehnder, "Adsorption of bacterial surface polysaccharides on mineral oxides is mediated by hydrogen bonds," Colloids and Surfaces B: Biointerfaces, vol. 9, pp. 331-343, 1997.

[3] A. G. L. Antonietta Splendiani, Cristiano Nicolella,, "Control of membrane-attached biofilms using surfactants," Biotechnology and Bioengineering, vol. 94, pp. 15-23, 2006.

Colloid and Interface Science, vol. 46, pp. 22-31, 1974.

[12] Y.-P. Yeh and J. J. Ramsden, "Quantification of the number of adsorbed bacteria on an optical waveguide," Journal of Biological Physics and Chemistry vol. 10, pp. 53-54, 2010.

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國科會補助計畫衍生研發成果推廣資料表

日期:2011/12/21

國科會補助計畫

計畫名稱: 二硫化鉬/金固體潤滑膜之磨潤特性研究 計畫主持人: 簡錫新

計畫編號: 99-2221-E-216-004- 學門領域: 加工與製造

無研發成果推廣資料

(23)

99 年度專題研究計畫研究成果彙整表

計畫主持人:簡錫新 計畫編號:99-2221-E-216-004- 計畫名稱:二硫化鉬/金固體潤滑膜之磨潤特性研究

量化

成果項目

實際已達成

數(被接受 或已發表)

預期總達成 數(含實際已

達成數)

本計畫實 際貢獻百

分比

單位

備 註

質 化 說 明:如 數 個 計 畫 共 同 成 果、成 果 列 為 該 期 刊 之 封 面 故 事 ...

期刊論文 0 0 100%

研究報告/技術報告

1 0 100%

研討會論文 1 0 100%

論文著作 篇

專書 0 0 100%

申請中件數 0 0 100%

專利 已獲得件數 0 0 100% 件

件數 0 0 100% 件

技術移轉

權利金 0 0 100% 千元

碩士生 2 0 100%

博士生 0 0 100%

博士後研究員 0 0 100%

國內

參與計畫人力

(本國籍)

專任助理 0 0 100%

人次

期刊論文 1 0 100%

研究報告/技術報告

0 0 100%

研討會論文 0 0 100%

論文著作 篇

專書 0 0 100% 章/本

申請中件數 0 0 100%

專利 已獲得件數 0 0 100% 件

件數 0 0 100% 件

技術移轉

權利金 0 0 100% 千元

碩士生 0 0 100%

博士生 0 0 100%

博士後研究員 0 0 100%

國外

參與計畫人力

(外國籍)

專任助理 0 0 100%

人次

(24)

其他成果

(

無法以量化表達之成

果如辦理學術活動、獲 得獎項、重要國際合 作、研究成果國際影響 力及其他協助產業技 術發展之具體效益事 項等,請以文字敘述填 列。)

成果項目 量化 名稱或內容性質簡述

測驗工具(含質性與量性)

0

課程/模組

0

電腦及網路系統或工具

0

教材

0

舉辦之活動/競賽

0

研討會/工作坊

0

電子報、網站

0

目 計畫成果推廣之參與(閱聽)人數

0

(25)

國科會補助專題研究計畫成果報告自評表

請就研究內容與原計畫相符程度、達成預期目標情況、研究成果之學術或應用價 值(簡要敘述成果所代表之意義、價值、影響或進一步發展之可能性) 、是否適 合在學術期刊發表或申請專利、主要發現或其他有關價值等,作一綜合評估。

1. 請就研究內容與原計畫相符程度、達成預期目標情況作一綜合評估

■達成目標

□未達成目標(請說明,以 100 字為限)

□實驗失敗

□因故實驗中斷

□其他原因 說明:

2. 研究成果在學術期刊發表或申請專利等情形:

論文:■已發表 □未發表之文稿 □撰寫中 □無 專利:□已獲得 □申請中 ■無

技轉:□已技轉 ■洽談中 □無 其他:(以 100 字為限)

3. 請依學術成就、技術創新、社會影響等方面,評估研究成果之學術或應用價 值(簡要敘述成果所代表之意義、價值、影響或進一步發展之可能性)(以 500 字為限)

本研究證明金膜層或二硫化鉬/金複合膜層能有效防止了氧氣或濕氣與二硫化鉬發生反 映,因此使二硫化鉬之使用壽命也因此大幅提升。研究成果對二硫化鉬固體潤滑膜之未來 發展具重要意義,未來該膜層可用於高濕度之環境,可解決許多超低摩擦機構件之表面處 理問題。目前已有國內廠商洽談技術細節及技術轉移之可能性。

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