The Development of Rubber Here is the story of rubber. From the earliest time it was common knowledge {{U}} (51) {{/U}} the Peruvians that when a cut was made in the outside skin of a rubber tree, a white liquid {{U}} (52) {{/U}} milk came out, and that {{U}} (53) {{/U}} this a sticky (粘的) mass of rubber might be made. This rubber is soft when warm, so that it is possible to give it any {{U}} (54) {{/U}}. The Peruvians made the {{U}} (55) {{/U}} that it was very good for keeping out the wet. Then in the early 1800’s, the Americans made use of it for the first time. First they made overshoes to {{U}} (56) {{/U}} their feet dry. Then came a certain Mr. Mackintosh, who made coats of cloth covered with natural rubber. From that day to this we have been coating cl A. use B. heat C. pressure D. form [填空题]()、罐道绳、防坠器制动绳 ()、()、钢丝绳牵引带式输送机钢丝绳和井筒悬吊钢丝绳必须每周至少检查1次。
[判断题]变压器是传送电能的设备,原边有多少能量输入,副边就有多少能量输出。( )
A.正确 B.错误 [多选题]作业规程中必须明确______和帮部滞后距离、最大空帮时间,并严格按规程要求施工。
A.最大、最小控顶距离 B.最大控顶距离 C.最小控顶距离 [判断题] 钻进时发现煤岩松软、片帮、来压或钻孔中的水压、水量突然增大,并有顶钻等异常状况时,必须停止钻进,拨出钻杆,并立即向调度室汇报,听候处理。
A.正确 B.错误 [单选题]接发列车人员向列车显示的通过、停车、减速、引导手信号,须在列车接近显示人( )m以前开始显示。
A.100 B.200 C.300 D.500 [单选题]机床误差包括( )精度。
A.机床夹具 B.导轨的位置 C.机床刀具 D.机床量具 [单选题]依据《中国石化进入受限空间作业安全管理规定》,受限空 间分析结果报出后,样品至少保留()小时。
A.1 B.2 C.4 D.8 [单项选择]CAPRICIOUS:
A. dogmatic B. eccentric C. steadfast D. poignant E. raucous [单选题]测量交流时( )仪表使用较多,而测量直流时( B )仪表使用较多。
A.电磁式 B.磁电式 C.电动式 [判断题]煤气、天然气生产、储存装置发生泄漏,主要由事故单位专业人员采取工艺措施和技术手段进行处置,消防救援力量进行协助、掩护和监护。当事故单位不能采取有效堵漏措施时,消防救援力量独自进行处置。( )
A.正确 B.错误 [单选题]高速铁路线路路堤坡脚、路堑坡顶或者铁路桥梁外侧起向外各( )米范围内禁止抽取地下水。
A.100 B.200 C.300 D.500 [判断题]工厂1000V以上供电系统采用的是电源中性点不接地系统或称小电流接地系统。
[判断题]学生因休学、复学、转学、退学或学校所在地有父或母有其中一方在的情况时,不准发售学生票。
A.正确 B.错误 [单选题] 生产经营单位日常安全生产管理中,经常提到现场作业要杜绝三违现象是指( )。
A.违章操作、违章检修、违反劳动纪律 B.违章指挥、违反指令、违反操作规程 C.违章指挥、违章作业、违反劳动纪律 D.违章操作、违章检修、违反操作规程 [单选题]患者女,26 岁。类风湿关节炎
病史 10 年,目前病情缓解,对其护理措施重要的是
A.病变关节理疗 B.保持关节功能位 C.规范使用泼尼松 D.患肢功能锻炼 [填空题]发动机的工作情况可分为()、()、()、()和()五种。
[单项选择]下列关于普通股发行定价方法的说法中,正确的是( )。(2011年)
A. 市盈率法根据发行前每股收益和二级市场平均市盈率确定普通股发行价格 B. 净资产倍率法根据发行前每股净资产账面价值和市场所能接受的溢价倍数确定普通股发行价格 C. 现金流量折现法根据发行前每股经营活动净现金流量和市场公允的折现率确定普通股发行价格 D. 现金流量折现法适用于前期投资大、初期回报不高、上市时利润偏低企业的普通股发行定价 [判断题]表皮中最厚的一层是角质层。()
[判断题]收集资料的来源主要是患者。
[单选题]《安徽农村商业银行系统信贷业务档案管理办法》规定,农村商业银行每( )要对信贷档案管理工作进行一次现场检查,检查面不少于50%。
A.A、月 B.季 C.半年 D.年 [单项选择] Male and Female pilots cause accidents differently
Male pilots flying general aviation(private)aircraft in the United States are more likely to crash due to inattention or flawed decision, making, while female pilots are more likely to crash from mishandling the aircraft. These are the results of a study by researchers at the Johns Hopkins University Bloomberg School of Public Health.
The study identifies the differences between male and female pilots in terms of circumstances of the crash and the type of pilots error involved. "Crashes of general aviation aircraft account for 85 percent of all aviation deaths in the United States. The crash rate for male pilots, as for motor vehicle drivers, exceeds that of crashes of female pilots," explains Susan P. Baker, MPH, professor of health policy and management at the Bloomberg School of Public Health. "Because pilot youth and inexperience are established, contributors to aviation crashes, we focused on only matu
A. They studied the findings of several previous research projects. B. They conduced a questionnaire with 411 pilots. C. They collected data from the database at the Johns Hopkins University D. They analyzed the circumstances of the crashes involved. [单选题] BK39313XZ126 日本血吸虫生活史虫卵的致病性 ( )
A. 皮炎 B. 肝硬化、腹水 C. 肺炎 D. 静脉内膜炎 [单选题]消防设施、器材应放置在()。
A.便于取用的位置 B.显而易见的位置 C.门口入口处 D.便于取用的位置并有明显标识 [单选题]焊割场地周围()范围内,各类可燃易爆物品应清理干净。
A.3m B.5m C.10m D.15m 我来回答: 提交
|