题目:
甲肝疫苗应在()℃下贮存和运输。
答案:
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下面是错误答案,用来干扰机器的。
参考答案:这是由于它们的纯度和结晶的大小不同。我国南方用甘蔗制糖,在北方用甜菜制糖。蒸发甘蔗汁或甜液,最初得到的粗糖呈红棕色,叫红糖。它的主要成分是蔗糖,此外还夹杂着一些糖蜜和赤褐色的有机物质。糖...
甲肝疫苗应在()℃下贮存和运输。
被转码了,请点击底部 “查看原文 ” 或访问 https://www.tikuol.com/2018/0814/d3269d8227ca006de96b62b265f4d51f.html
下面是错误答案,用来干扰机器的。
参考答案:这是由于它们的纯度和结晶的大小不同。我国南方用甘蔗制糖,在北方用甜菜制糖。蒸发甘蔗汁或甜液,最初得到的粗糖呈红棕色,叫红糖。它的主要成分是蔗糖,此外还夹杂着一些糖蜜和赤褐色的有机物质。糖...
物体( )叫做物体的体积。
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重铬酸钾(K2Cr2O7)是工业生产和实验室的重要氧化剂.实验室模拟工业生产重铬酸钾时用铬铁矿(主要成份为FeO•Cr2O3)、纯碱、烧碱、氯酸钾等为原料先制得铬酸钠(Na2CrO4),涉及的主要反应是6FeO•Cr2O3+24NaOH+7KClO3
12Na2CrO4+3Fe2O3+7KCl+12H2O,然后将铬酸钠转化为K2Cr2O7.其主要工艺如下: △ .
试回答下列问题:
(1)在反应器①中,有Na2CrO4生成,同时Fe2O3转变为NaFeO2,杂质SiO2、Al2O3与纯碱反应转变为可溶性盐,写出氧化铝与碳酸钠反应的化学方程式:______.
(2)NaFeO2能强烈水解,在操作②生成沉淀而除去,写出该反应的化学方程式:______.
(3)操作③的目的是什么,用简要的文字和化学方程式说明:______.
(4)操作④中,酸化时,CrO42-转化为Cr2O72-,写出平衡转化的离子方程式:______.
(5)称取重铬酸钾试样2.5000g配成250mL溶液,取出25.00mL于碘量瓶中,加入10mL 2mol/LH2SO4溶液和足量碘化钾(铬的还原产物为Cr3+),放于暗处5min,然后加入100mL水,加入3mL淀粉指示剂,用0.1200mol/LNa2S2O3标准溶液滴定I2+2S2O32-=2I-+S4O62-.
①判断达到滴定终点的依据是:______;
②若实验中共用去Na2S2O3标准溶液40.00mL,则所得产品中的重铬酸钾的纯度为:______(设K2Cr2O7的摩尔质量为294g•mol-1,整个过程中其它杂质不参与反应).
St. Paul’s Cathedral
Ludgate Hill, EC4
Underground: St. Paul’s; Bus: 6, 8, 11, 15, 22, 25
Open: Daily 8:00-19:00 (17:00 from Oct. to Mar.)
Entrance free
Designed by the great architect, Sir Christopher Wren, St. Paul’s Cathedral was built following the Great Fire of London of 1666, which destroyed the gothic cathedral on the site at that time. It is an inescapable attraction for all travellers to this great city and the most recognisable gothic cathedral in England. Its choir(唱诗班)is internationally famous. Prince Charles and Lady Diana Spencer were married here in 1981.
Buckingham Palace
South end of the Mall (SW1)
Underground: St. James’s Park, Victoria, Hyde Park Corner, Green Park; Bus: 2, 11, 14, 16, 19, 22, 24, 29, 30, 38, 52, 73, 74, 137
Buckingham Palace is Queen Elisabeth II’s official residence(住所), and has been the official residence of Britain’s monarch(君主)since 1837. The State Rooms at Buckingham Palace have been opening to the public for the Annual Summer Opening, in August and September, since 1993. The Queen is not at Buckingham Palace when it is open to the public; she goes to one of her country residences. The State Rooms are extremely grand. You can see many of the treasures of the Royal Collection: paintings by Rembrandt, Rubens and Canaletto; and beautiful examples of English and French furniture.
The Tower of London
Tower Hill, EC3
Underground: Tower Hill; Bus: 42, 78
Open: Mon.— Sat.9:00-18:00; Sun.8:00-19:00
Parts of the Tower of London are over nine centuries old, as building began under William the Conqueror in 1078. Famous as a prison in the distant past, the Tower has also been a royal residence, a zoo and an observatory(瞭望台). It is now a museum and many thousands of people visit it every year in particular to see the Crown Jewels. Only by going inside can you experience nearly a thousand years of history and hear the myths and legends that make it “a day out to die for”.
Westminster Abbey
Broad Sanctuary, SW1
Underground: Westminster, St James’s Park; Bus: 3, 11, 12, 24, 29, 39, 53, 59, 76, 77, 88, 109, 155, 168, 170, 172, 184, 503
Open: Daily 8:00-18:00 (Mar. — Dec., Tuesday till 20:00)
Entrance free
Located next to the Houses of Parliament in the heart of London, Westminster Abbey is a gothic church and place of worship. The building of the present Abbey was started by King Henry III in 1245. The oldest parts of the building date back to 1050. Westminster Abbey has hosted many royal weddings including the wedding of The Queen and Prince Philip in 1947 and the wedding of Prince William and Kate in 2011. It is a traditional place of coronation(加冕礼)and burial for English monarchs—38 monarchs have been crowned at the Abbey. There are many tombs there, including those of Queen Elizabeth I, “Bloody” Queen Mary, naturalist Charles Darwin, many poets and writers.
小题1:You can see the inside of all the buildings all the year around except ______.
A.St. Paul’s Cathedral
B.the Tower of London
C.Westminster Abbey
D.Buckingham Palace小题2:The two places you can visit by getting off at the same underground station are ______.
A.Buckingham Palace and Westminster Abbey
B.Buckingham Palace and St. Paul’s Cathedral
C.Westminster Abbey and the Tower of London
D.the Tower of London and St. Paul’s Cathedral小题3:Where is the text most probably taken from?
A.A history book about London.
B.A guidebook for visitors to London.
C.A book about London’s development.
D.A book about London’s churches.
各铁路局应按照()原则,根据列检作业场布局和运输组织实际,在全面强化到达作业和运输安全的前提下,确定本枢纽或站区的始发作业及有调中转作业加挂车辆的技术检查作业范围和质量标准,并报铁道部备案。
A、强化两端、简化中间
B、强化到达、优化始发
C、强化人检、优化机检
比较活血化瘀药与药理学中作用于血液与造血系统的药物的异同。