为使钻井仪表起防爆作用，内部需予充（）之间压力的氮气。

某技师塑瓷时由于反复烘烤，造成瓷粉透明度下降，其原因是（）

A.瓷粉熔点升高

B.瓷粉热膨胀系数增大

C.碳酸盐分解

D.磷酸盐分解

E.瓷粉熔点降低

在堤防工程中，铲运机兼作压实机械时，轮迹应搭压轮宽的（）。

A.1/2

B.1/3

C.1/4

D.1/5

阅读下列短文，回答问题：

不同的植物，开花的年龄不同，开花的季节和时间也不一样．冬小麦秋季播种萌发，第二年夏初开花和结果，对这类植物来说，秋末冬初的低温就成为开花必需的条件；美洲烟草在夏季长日照下，株高达3m-5m也不能开花，但生长在冬季温室中，日照时间短，植株高不到1m即可开花．

（1）无论花的形态怎样，花中主要的结构是花蕊，原因是______．

（2）从短文中可以得知，影响开花的外界条件主要有______．

（2）春季补种冬小麦，将会只长苗而不开花结果．其中的原因是______．

（3）播种的“小麦种子”在结构层次上属于______，是由______发育而成的．

“日键关”中的“键”意思是（）选项

A.门闩

B.门锁

C.门把

D.户枢（门轴）

E.关键

(36) have greeted Queen Elizabeth Ⅱ as she appeared outside (37) in a pink suit and hat on her 80th birthday. And (38) working grandmother shows no signs of slowing down and has genes on her side -- her mother died at 101. Queen Elizabeth’s husband, Prince Philip, followed close behind as she (39) the castle’s King Henry VIII gate, Voice of America reports. A military (40) played and a 21-gun salute (41) nearby ahead of another 41-gun salute in London’ s Hyde Park later in the day Friday. Prince Charles is (42) a birthday dinner for the (43) at a palace in London’s Kew Gardens. Queen Elizabeth has received 37,000 birthday cards and e-mails from around the world, according to (44) Queen Elizabeth Ⅱ issued a (45) saying she (46) by the messages. In an ITV News survey, Elizabeth was (47) the most popular royal. Bottom of the survey came Camilla Parker-Bowles, Duchess of Cornwall, who last year married the queen’s eldest son, Charles, after a tortuous 35-year (48) . In her 80s, Queen Elizabeth Ⅱ remains perhaps the most (49) . She is known for her penchant for brightly colored suits and hats. French designer Sonia Rykiel once criticized the Queen of England about the way she dresses. She called the Queen "the worst dressed person in the UK". "The Queen is one of the worst dresses people in the UK. She should stop wearing those bright suits and hats ..." Sonia Rykiel said. "A woman in her position should start dressing in a more (50) and serious manner." Frankly, we sold our Sonia Rykiel sweaters cardigans on eBay (51) after this interview. According to a senior royal aide, "The Queen proudly wears British designers. She wears (52) and stylish clothing which is right for the kind of work she does." Her main (53) include (54) photography, and dogs, especially her Pembroke Welsh Corgis. Queen Elizabeth II is Europe’s (55) living monarch. And lest we forget, Queen Elizabeth Ⅱ is the Queen of Canada, too.