用戶【蘇志騰】點評問題和點評內容

【評論主題】40.以雙酚醇基丙烯酸甲酯(bis-GMA)為基質之複合樹脂常用之偶合劑(coupling agent),下列何者正確?(A)羥基胺類(hydroxylamine) (B)環氧類(epoxy) (C)

【評論內容】

Phillips' Science of Dental Materials, 12e. P.278

In 1962, Bowen developed a new type of composite mate- rial that largely overcame these problems. Bowen’s main innovations were bisphenol-A glycidyl dimethacrylate (bis- GMA), a monomer that forms a cross-linked matrix that is highly durable (see Chapter 6), and a surface treatment utilizing an organic silane compound called a coupling agent to bond the filler particles to the resin matrix.

【評論主題】36.牙科用不銹鋼材料中主要元素鉻(Cr)的含量(wt%)範圍為何?(A)1~10 (B)11~30 (C)31~50 (D)51~60

【評論內容】

Phillips' Science of Dental Materials, 12e P.406

When approximately 12% to 30% chromium by weight is added to carbon steel, the alloy is commonly known as stain- less steel. 

國考參考書第406頁有提到完整敘述,請解答提出國考參考書之內容,以免產生爭議

【評論主題】34.有關加成式矽化物(addition silicone)印模材的敘述,下列何者錯誤?(A)聚合過程中會釋放出氫氣,可能是從Si-H unit而來 (B)如果用石膏倒模,要等30分鐘以上才可倒模 (

【評論內容】

無其餘選項描述之根據,雖C確定錯誤,但無法說明其餘選項沒有錯誤的可能性

事實上A選項在P.155的圖可以發現Si旁有四個化學鍵,其中兩個與氧鍵結形成聚合物,另一為CH3屬安定官能基,可反應的基團只有H

C,D選項在P.154Addition silicone標題下第二段最後三行

Manufacturers may add a noble metal, such as palladium, as a scavenger for the released hydrogen gas. The impression should be left overnight if epoxy will be used for pouring models.