关于电磁波和现代通信,下列叙述中错误的是( ) A.电磁波可以在真空中传播 B.

题型:选择题

问题:

关于电磁波和现代通信,下列叙述中错误的是(  )

A.电磁波可以在真空中传播

B.电磁波的频率越高,在空气中传播的速度越大

C.电磁波是一种资源,人们应该合理使用

D.微波通信、卫星通信、光纤通信、网络通信都可以用来传递信息

考点:声与信息电磁波的传播
题型:选择题

可用作乳剂型基质防腐剂的是()

A.硬脂酸

B.液体石蜡

C.吐温80

D.羟苯乙酯

E.甘油

题型:选择题

患者,男,40岁,有进行性全身淋巴结肿大,反复发热腹泻,体重减轻,查出有卡氏肺囊虫性肺炎并伴有神经系统疾病,疑为AIDS患者,其HIV病毒的筛选试验是()

A.免疫扩散法

B.免疫印迹法

C.ELISA法

D.免疫散射比浊法

E.淋巴细胞转化试验

题型:选择题
完形填空(共20小题;每小题1.5分,满分30分)
阅读下面短文,从短文后各题所给的四个选项(A,B,C,D)中,选出可以填入空白处的最佳选项,并在答题卡上将该项涂黑。
  Summer is the best time on the Island of the Blue Dolphins (海豚). The sun is warm then and the winds blow out of the west,   16  out of the south.
It was   17  these days that the ship might return and now I   18 most of my time on the rock,   19  out from the headland(水中凸起的陆地) into the east, towards the country  20  my people had gone, across the   21  that was never-ending.
Once  22  I watched, I saw a small object which I took to be the ship, but a stream of water   23  from it and I knew that it was whale (鲸鱼)spouting (喷水). During those summer days I saw nothing   24 .
The first storm of winter   25  my hopes. If the white men's ship were   26     for me it would have come during the time of good   27 . Now I would have to wait  28  winter was gone, maybe longer.
The thought of being   29  on the island while so many suns rose   30  the sea and went   31  back into the sea   32  my heart with loneliness. I had not felt so  33  before because I was sure   34  the ship would return as Matasaip had said   35  would. Now my hopes were dead.
小题1:
A.totallyB.alreadyC.entirelyD.sometimes
小题2:
A.duringB.forC.afterD.between
小题3:
A.spentB.sharedC.paidD.devoted
小题4:
A.lookB.to lookC.lookingD.looked
小题5:
A.whenB.whereC.whichD.until
小题6:
A.islandB.seaC.lakeD.ocean
小题7:
A.sinceB.thoughC.whileD.till
小题8:
A.roseB.raisedC.grewD.set
小题9:
A.differentB.ordinaryC.elseD.valuable
小题10:
A.encouragedB.endedC.sparedD.limited
小题11:
A.leadingB.movingC.comingD.following
小题12:
A.weatherB.patternC.rainD.fog
小题13:
A.afterB.asC.untilD.while
小题14:
A.quietB.aloneC.calmD.alive
小题15:
A.ofB.inC.toD.from
小题16:
A.rapidlyB.quicklyC.slowlyD.fully
小题17:
A.pumpedB.setC.filledD.full
小题18:
A.lonelyB.strictC.boringD.empty
小题19:
A.whetherB.andC.thatD.when
小题20:
A.itB.heC.thatD.this
题型:选择题

Kappa值为0.61~0.80时可定为()

A.完全不可靠

B.可靠度不合格

C.可靠度中等

D.可靠度优

E.完全可靠

题型:选择题

下列哪种物质不是甘油磷脂的成分()

A.胆碱

B.乙醇胺

C.肌醇

D.丝氨酸

E.神经鞘氨醇

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