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问题 选择题

欲除去NaHCO3溶液中少量的Na2CO3，可选用的试剂是

A．饱和石灰水

B．NaOH溶液

C．盐酸

D．CO2

答案

答案：D

题目分析：除去杂质的原则是：”不增不减”。即不增加新的杂质，不减少被提存的物质。A饱和石灰水与碳酸氢钠、碳酸钠都发生反应。错误。B、NaOH溶液与碳酸氢钠发生反应生成碳酸钠。错误。C、碳酸氢钠、碳酸钠都会发生反应导致变质。错误。D. 向溶液中通入二氧化碳气体，这时发生反应：Na2CO3 +CO2↑+H2O=2NaHCO3,杂质变为被提纯的物质。符合要求。正确选项为：D。

多项选择题

对3kV及以上的并联补偿电容器组的下列哪些故障及异常运行方式，应装设相应的保护装置？（）

A.电容器内部故障及其引出线短路

B.电容器组和断路器之间连接线短路

C.电容器组中某一故障电容器切除后所引起的过电压

D.电容器组的单相接地
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问答题

一、已知资料：
1．信用证：
Date of Issue :091020
Form of Doc. Credit :IRREVOCABLE
Doc. Credit Number :MNK27101300032
Expiry :Date 091115 Place IN BENEFICIARY’S COUNTRY
Applicant :PT. MANE
186 IHONBASHI—CHO
PUSAN, KOREA
Beneficiary :XIAMEN ARTS & CRAFTS IMP. & EXP. CORP.
628 CHANGSHA NAN ROAD,
XIAMEN, CHINA
Partial Shipments :ALLOWED
Transshipment :ALLOWED
Loading in Charge :XIAMEN, CHINA
For Transport to… :PUSAN, KOREA
Latest Date of Ship. :091105
Descript. of Goods :CHINA ORIGIN
ARTIFICIAL FTOWFRS
AB-06001 5000DOZ @ USD2.50/DOZ
AB-07049 2500DOZ @ USD2.80/DOZ
AS PER S/C NO. 97A/KF002A DATE OCT. 15, 2009
CIF PUSAN
Documents Required :SHIPMENT ADVICE IN FULL DETAILS INCLUDING
SHIPPING MARKS, CONTAINER NUMBERS, VESSEL
NAME, B/L NUMBERS, VALUE AND QUAN3TFY OF
GOODS MUST BE SENT ON THE DATE OF SHIPMENT
TO APPLICANT.
2．其他资料：
INV. NO. : 9765335 B/L DATE: OCT. 28, 2009
B/L NO. : DSA97-1102 SHIPPING MARKS: PT/PUSAN
PACKINC: AB-06001 50DOZ/CTN G. W. : 23KGS/CTN N. W. : 18KGS/CTN
AB-07049 50DOZ/CTN G. W. : 19KGS/CTN N. W. : 13KGS/CTN
MEASUREMENT: (40×50×80)CM/CTN DATE OF ADVICE: OCT. 29, 2009
CONTAINER NO. MSCU 4097561 (20’) MSCU 4097615 (40’)
NAME OF STEAMER: SUI 301/NORASIA V.49-3 W/T DAIIAN
二、根据已知资料缮制装船通知

厦门工艺进出口公司

XIAMEN ARTS & CRAFTS IMP. & EXP. CORP.

628 CHANGSHA NAN ROAD. XIAMEN, CHINA

To Messrs. : INVOICE NO. : ______
SHIPPING ADVICE

Name of Commodity: ______
Quantity: ______
Invoice Value: ______
Name of Carrying Steamer: ______
Date of Shipment: ______
Shipping Marks: ______
Credit No. : ______
Port of Loading: ______
Port of Discharge: ______
B/L No. : ______
Container No. : ______
XIEMEN ARTS & CRAFTS IMP & EXP. CORP.
628 CHANGSHA NAN ROAD.
XTEMEN CHTNA
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