首页
外语
计算机
考研
公务员
职业资格
财经
工程
司法
医学
专升本
自考
实用职业技能
登录
外语
When was the paintbrush first utilized?
When was the paintbrush first utilized?
admin
2010-03-19
30
问题
When was the paintbrush first utilized?
An ancient paintbrush used by a prehistoric cave artist survives from 30, 000 years ago. But the bristles of the new nanobrushes are made of tiny carbon filaments—thirty billionths of a meter across and a few millionths long. The brush handles they’re attached to are comparatively large—thicker than a human hair! The researchers have taken microscope pictures showing the brushes can be used to sweep up tiny pieces of nanodust on dirty surfaces.
The researchers also used their brushes to paint microstructures; and by coating the hairs with absorbent com- pounds, they could soak poisonous substances from water. If the tiny tools prove robust enough, they could one day find medical uses, or sweeping away unwanted dirt.
选项
A、3,000 years ago.
B、5,000 years ago.
C、In the primitive society.
D、30,000 years ago.
答案
D
解析
转载请注明原文地址:https://jikaoti.com/ti/S4HMFFFM
0
专业英语四级
相关试题推荐
Whenwasthepaintbrushfirstutilized?
Whenwasthepaintbrushfirstutilized?
Whenwasthepaintbrushfirstutilized?
Whenwasthepaintbrushfirstutilized?
随机试题
症见胁肋胀痛,胸闷太息,纳食减少,腹胀便溏,肠鸣矢气,可诊为()(2002年第24题)
医疗护理过程中要签全名的有
患者带下量多,绵绵不断,质清稀如水,腰膝酸软,畏寒肢冷,小腹冷,夜尿多,舌淡苔白润,脉沉迟。治疗首选方剂是()
A、溶剂一熔融法B、复凝聚法C、饱和水溶液D、塑制法E、涂膜法微囊化制备方法()。
用重点审查法审查施工图预算时,审查的重点有()。
附属内驱力表现最为突出的时期是()。
专家型教师和新教师教学行为的差异主要表现在_________、课堂教学过程和课后评价三个方面。
商品不是物。而是物掩盖下的社会生产关系。马克思的这一论断的含义是()
根据所给资料,回答下列小题。该省2011年研究生招生人数占普通本专科招生人数的:
教育目的提出无需考虑受教育者的特点。
最新回复
(
0
)