中臺科技大學 99 學年度研究所碩士班考試入學試題卷

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中臺科技大學 99 學年度研究所碩士班考試入學試題卷

＊本試題卷可以使用工程用計算機

1. A 235mg ²³⁵U was irradiated at a flux density of 2×10¹⁴ neutrons cm^-2s^-1 for 66 hours. Calculate the radioactivity( in mCi) of ⁹⁹Mo would be produced？10％

（⁹⁹Mo：half life＝66hr.；reaction cross section(σ)＝1×10^-26 cm²）

2. Classify the following nuclides which are isotones、isobars、isomers and isotopes？

20％

14C，¹⁴N，¹⁶O，⁹⁹Tc，^99mTc，¹²⁵I，¹³¹I，¹³³I，¹³¹Xe，^137mXe，¹³¹Cs，¹³⁷Cs，¹³¹Ba，

137Ba，^137mBa

（atomic number(Z)：C: 6，N: 7，O: 8，Tc: 43，I: 53，Xe: 54，Cs: 55，Ba: 56）

3. Iodine-131 has a half-life of 8 days. If the amount of iodine-131 in a sample is 8 g, How much iodine-131 will remain after 32 days？ 10％

4. Explain the following term: 15％

a. transient equilibrium b. one-over-ν law（1/ν_n）

c. neutron activation analysis(NAA) d. Internal conversion

e. Fricke dosimeter

背面尚有題目

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5.Calculate the specific activity (in Bq/g) of ²³²Th(t1/2＝1.4×10¹⁰ years)？

（atomic mass of Th is 228amu、 100％natural abundance ²³²Th）10％

6.Sketch the relationship of the output signal of gas-filled counts to the applied voltage and express the names of different regions in figure。10％

7. An electrodeposited sample of ⁶⁰Co for an isotope dilution analysis experiment yield 1826 counts in a 1.0 minute counting period. For the same detector, 128 background counts were recorded in a 1.0 minute counting period. What is the net counting rate of ⁶⁰Co sample？10％（Notes：the answer is showed as X±σ）

8. Please fill in the nuclear reactions according the change numbers of neutrons and protons： (d，n)、(n，p)、(p，pn)、 (n，γ)、(α，n) 15％

ΔN ΔP

－2 －1 0 ＋1 ＋2

＋2

＋1

0 Original

Nucleus

（0，0）

－1

－2

Note：

ΔP is the change numbers of protons ΔN is the change numbers of neutrons