交互式操作系统允许用户频繁地与计算机对话,下列不属于交互式操作系统的是 ______

题型:单项选择题

问题:

交互式操作系统允许用户频繁地与计算机对话,下列不属于交互式操作系统的是 ______。

A.Windows系统

B.DOS系统

C.分时系统

D.批处理系统

考点:计算机等级考试MSOffice一级MSOffice笔试
题型:单项选择题

(18分)废旧硬质合金刀具中含碳化钨(WC)、金属钴(Co)及少量杂质铁,利用电解法回收WC和制备CoxOy,的工艺流程简图如下:

(1)电解时废旧刀具作阳极,不锈钢作阴极,盐酸的作用是______。

(2)通人氨气的目的是调节溶液的pH,除去铁元素。由表中的数据可知,理论上可选择pH最大范围是____________。

(3)实验测得NH4HCO3溶液显碱性,制备CoCO3时,选用的加料方式是_______(填代号),原因是_______。

a.将滤液与NH4HCO3溶液同时加入到反应容器中

b.将滤液缓慢加入到盛有NH4HCO3溶液的反应容器中

c.将NH4HCO3溶液缓慢加入到盛有滤液的反应容器中

写出生成CoCO3的离子方程式______________________________________。

(4)实验中获得的若洗涤不充分,在焙烧时会产生污染性气体,该污染性气体的成分为_______________(填化学式)。

(5)实验室用下列装置制取,并测定其化学式。

①装置A制得的中含有少量Cl2,则装置B中所盛放的试剂为______(填代号)。

a.NaHCO3溶液    b.NaOH溶液    c.KMnO4溶液    d.饱和NaCI溶液

②在CoCO3完全转化为后,若称得E管增重4.40g,D管内残留物质的质量是8.30g,则生成物的化学式为____________。

③若缺少装置F,则导致的值______(填“偏大”、“偏小”或“无影响”)。

题型:单项选择题

如图所示,在阳光下和黑暗的情况下,植物叶片的气孔放出的气体是不同的,下列对气孔a和b放出的主要气体说法正确的是(  )

A.a、b都放出氧气

B.a、b都放出二氧化碳

C.a放出氧气,b放出二氧化碳

D.a放出二氧化碳,b放出氧气

题型:单项选择题

原发性与继发性三叉神经痛的主要鉴别是根据()

A.是否存在"触发点"

B.是否伴有神经系统体征

C.是否伴有角膜炎

D.是否伴有牙齿疾患

E.是否疼痛范围较小

题型:单项选择题


A patrol team of sea lions and dolphins featured in a large-scale military exercises being conducted by the U. S. and its allies in the Pacific Ocean. The machine (1) took part in simulated mine recovery and mine detection missions during the biennial Rim of the Pacific Exercise (RIMPAC) war games. The (2) started on June 19 and will run (3) Friday.
"There are a number of mechanical systems that work in those areas. (4) high-tech gadgets deployed by the military can’t (5) the natural skills of dolphins and lions," said Tom Lapuzza, spokesman for UN Navy’s Marine Mammal Program. Sea lions have "incredible good underwater (6) " and can dive down to 300 meters to catch a recovery line to a mine, he said. Dolphins use sonar to (7) mine.
Human beings have a long (8) of training animals to join the military. Horses have been the most widely-used animals (9) the recorded history of (10) . In early times, horses were used to (11) chariots or to (12) armored forces. With the development of modem weapons and motorized (13) , the use of horses for military purposes fell into (14) . (15) , horses were still used (16) by the German army during World War II for transporting (17) and equipment, including artillery.
During World War II, (18) with explosives strapped to their backs were used as anti-tank weapons. In other (19) , they were used for detecting mines. Some dogs were also used as messengers.
Other animals have also (20) in the military. Recorded history shows the use of elephants for military purposes as early as 1,100 B. C.. They were employed during World War II by both the Japanese army and the (21) .
There are records showing that over 100,000 reindeer were used by Finland to tow sleds during World War II. They carried the (22) to hospitals, brought supplies to the troops and moved heavy anti-tank weapons. It is well documented that oxen have been (23) used in war as improvised beasts of burden. During World War II, spiders were employed by the Allies to spin silk for (24) in cross-hairs on bomb scopes and other optical instruments. People also are finding that Vampire bats’ ability to use echolocation is very interesting as we (25) to learn how it works and it may benefit the army.

题型:单项选择题

混凝土泵按照机动性分为柱塞式和挤压式两种。

更多题库