問題詳情
3. Which one is WRONG for gas chromatography?
(A) The mobile phase does not interact with molecules of the sample.
(B) Capillary columns provide higher resolution than packed columns.
(C) Reproducible retention times require control of the column temperature.
(D) Immobilized liquid phase should be chemical inert and low volatile.
(E) This method is applicable to species that are appreciably non-volatile.
(A) The mobile phase does not interact with molecules of the sample.
(B) Capillary columns provide higher resolution than packed columns.
(C) Reproducible retention times require control of the column temperature.
(D) Immobilized liquid phase should be chemical inert and low volatile.
(E) This method is applicable to species that are appreciably non-volatile.
參考答案
無參考答案
內容推薦
- 統一標準螺紋 -20UNC-3A-LH，以下何者錯誤？(A)三線螺紋 (B)外螺紋 (C)每吋20牙 (D)左螺紋。
- 【題組】What's John's phone number?(A) Three-three-eight-seven-two-one-four.(B) Three-three
- 【題組】What happens when we “combine” two things?(A) They are a pair. (B) They are the same thing. (
- 【6-8】Today, many people work to help others when they are taking a vacation in a foreigncountry, and
- 【題組】The Wangs went to Fusing World today. Mr. Wang watched Water Dance only.Their twin daughters,
- 【3-5】(At TrueLove Animal Home)Mr. Simpson: Honey, why are we here? Today is our wedding anniversary,
- 下圖所示的類比濾波器電路【題組】如上圖所示的類比濾波器電路，屬於何種形式？(A)低通 (B)高通 (C)帶通 (D)帶拒。
- 如圖所示之輪系，若60齒之齒輪逆時針1rpm，則20齒的齒輪為 (A)逆時針6rpm (B)順時針6rpm (C)順時針4rpm (D)逆時針4rpm。
- 如【圖 23】所示，一直桿受到四個軸力的作用，哪一段有最大的軸向內力？(A) a 段(B) b 段(C) c 段(D) d 段
- Ninhydrin is the hydrate of a triketone and is in equilibrium with it. In the following statement
內容推薦
- 【題組】(A) yours (B) they (C) his (D) my
- A fatty acid gives nonanal and 9-oxononanoic acid on ozonolysis followed by zinc treatment. This
- 【題組】(A) for (B) of (C) with (D) to
- Cell membranes are composed mostly of _____________ organized into a lipid bilayer which serves a
- 某個樑截面如【圖 20】所示，該截面受到的剪力為 4 kip，請問最大的剪應力值為若干 psi？（提示：Qmax= 75(5✖10) =225 in3）(A) 50 psi (B)
- 【題組】( )Where does Ella work(工作)?(A) (B) (C) (D)
- 在周轉輪系中某輪之相對角速度為其絕對角速度與旋臂角速度之(A)差 (B)積 (C)比 (D)和。
- 一周轉輪系機構如圖所示，NA=10rpm順時針旋轉，NB=6rpm逆時針旋轉，則C輪轉速與旋轉方向為何？ (A)8rpm順時針旋轉 (B)8rpm逆時針旋轉 (C)5rpm順時針旋轉 (D
- Wohl degradation: a multi-step reaction sequence for degrading an aldose into the next lower homo
- Which of the following contains the metal with the lowest oxidation number?(A) CaCl2 (B) FeSO4 (C
- 垂直力 120 N 作用於桿件的端點 A 處，如圖所示。請問此 120 N 作用力 對 O 點的力矩(moment)為何？(註：sin60° = 0.866 ，cos60° = 0.5 ) (A
- 某懸臂樑截面為正方形，邊長為40mm。 受到800 N 的軸向拉力，請問軸向平均拉應力(average tensile stress) 為何？ (A)200 kPa (B) 300 kPa (C)
- 【題組】接續第 32 題，濾波器階數為何？(A)4 (B)3 (C)2 (D)1。
- 一長溝槽橫斷面如【圖 24】所示，令 h 為流體深度，為流體質量密度，g 為重力加速度，單位長度的垂直面槽壁所受到的最大力矩為何？ (A)ρghB/6 (B) ρgh2B/2 (C) ρgh2
- 雙螺旋導程為螺距之(A) 倍 (B)1倍 (C)2倍 (D)4倍。
- 【題組】接續第 32 題，直流電壓增益為何？(A)0 (B) (C) (D)
- 有關剪力流(shear flow)的敘述，下列何者錯誤？(A)剪力流是沿著結構樑之軸方向的單位面積剪力(B)常應用於分析人為建造的複合部件(composite parts)結構(C)鎖緊結構樑的
- 在太陽行星齒輪裝置中，活塞每往復一次，則曲柄迴轉(A)1次 (B)2次 (C)3次 (D)4次。
- 於受力的簡支樑，其力矩-曲率(moment-curvature)關係中，下列何者是正確的表示式？（其中：ρ =曲率半徑，y=樑的垂直軸向位移座標，ε =應變量，M=樑的內力矩(internal
- Lactose yields 1 equivalent D-glucose and 1 equivalent _________ on hydrolysis.(A) D-fructose (B)
- 如圖所示之周轉輪系，若輪2轉速為＋3，旋臂轉速為－1，試求輪輪4之轉速分別為若干(旋臂繞輪2軸心旋轉)？ (A)－19，＋(B)－21，＋(C)＋19，－(D)＋9，－5。
- Which of the following Fischer projections of glyceraldehydes represent the same configuration w
- 安裝網頁主機，為節省軟體經費並有合法版權，下列哪一個作業軟體較適合？ (A)Linux(B)OS/ 2(C)Windows 7(D)Window 8。
- 某延性材料的拉伸實驗，在線彈性範圍內，測得平均拉應力為 336MPa 時，平均伸長應變為 0.0048，請 問該材料的彈性模數(modulus of elasticity)為何？(A)50GPa(
- Jack: Today is Grandma’s birthday. _________ is going to happen.Ken: That’s right. I can’t wait