Snake Robots
by 孙尉翔 on 2月 18, 2009
A review on snake-inspired robot design was published on the IOP journal, Bioinspirations and Biomimetics, 2009 ,4, 021001. DOI: 10.1088/1748-3182/4/2/021001. The introduction paragraphs of the review described several advantages of snake-like robot compared with other types of design, which is quite interesting to read. But I did not go into the detail of the review. There are images of various design of snake robots in this paper. And this reminds me to search some videos in Youtube.com. It seems that these robots don’t just move like snakes. They also moves like worms, or something not seen in nature.
Liquid Mirror
by 孙尉翔 on 2月 18, 2009
Liquid Mirror Telescope
The first time I heard that liquid mirrors worth studying was from a Nature’s News & Views article.
Rotating liquid that creates a parabolic surface enables human to
conceive about really big telescopes that have to be built on the moon.
The Nature article praised the use of ionic liquids (ILs)
— liquids that are hardly volatile — for liquid mirror support, because
in the moon the working environment is vacuum. And it is also cold
there, so the liquid mirror should also melt at as low a temperature as
possible.
Man-Made but Living Systems – Bio Besides Mimetics and Inspirations
by 孙尉翔 on 2月 18, 2009
According to Wikipedia.org which though is not often desirable, the meaning of the word biomimetics does not include the direct utilization of the functional part of living structures. We have found lotus leaves superhydrophobic. But biomimetically we didn’t directly grow lotus crops for water-repelling coatings, nor did we try to culture similar layer from lotus tissue. Rather, we got ‘inspired’ and started ‘mimicking’ the structure by purely artificial technologies we are familiar with. Similar situation is in computer science—obviously we didn’t try to clone some people exclusively for intellectual production, leaving us a comfortable yet improving future without necessity to think over anything complex. Rather, we turn to silicon-based computers and only wish these computers can become smarter by mimicking the logical structure of brain—what the cyberneticists are doing.
Do Chinese Civilians Hate Scientist?
by 孙尉翔 on 3月 7, 2008
这是我在Nature Network博客上的一篇文章，最新得知已经被推荐到Nature.com主页上了。
UPDATE: The whole post was revised to avoid misunderstanding. Some parts are bolded.
The first line is the simplified Chinese of the phrase ‘experts and professors’, and the second line is a very popular homophonous variation of the phrase and the meaning changed to ‘rock owner and roaring creature’
Research shows that among several countries in the world China ranks very low in science literacy of the public, especially in understanding the methodology of science as well as the relationship between science and society.
Yes. If you start a poll (I mean a undisturbed, full democratic poll) among the people here, whether to dismiss the Chinese Academy of Sciences and that of Engineering, the answer is very likely to be positive.
Two committee members from Chongqing province proposed this idea to the ongoing 11th National Committee of the Chinese People’s Political Consultative Conference. This news on the web received thousands of comments supporting the proposal. (If you can read Chinese see how people applause to this idea. If you can’t, just notice the number of supporters.)
重读《高分子物理》，真是收获良多。今晚看到了关于SBS共聚物热塑性弹性体的段落时候，连系到近年来很火爆的软物质、嵌段共聚物自组装等研究，很有体会。
SBS是塑料链和橡胶链共聚产物，跟一务的塑料或橡胶相比，其显示出一种特有的应变软化现象，即所谓的“应变诱发塑料——橡胶转变”。其现象如下：
当其中的塑料相和橡胶相的组成比接近1:1时，材料室温下像塑料，其拉伸行为起先与一般塑料的冷拉现象相似。在应变约5%处发生屈服成颈，随后细颈逐渐发展，应力几乎不变而应变不断增加，直到细颈发展完成，此时应变约200%，进一步拉伸，细颈被均匀拉伸，应力可进一步升高，最大应变可高达500%，甚至更高。可是如果移去外力，这种大形变却能迅速基本回复，而不像一般塑料强迫高弹性需要加热到Tg或Tm附近才回复。而且，如果接着进行第二次拉伸，则开始发生大形变所需要的外力比第一次拉伸要小得多，试样也不再发生屈服和成颈过程，而与一般交联橡胶的拉伸过程相似，材料呈现高弹性。……更为奇特的是经拉伸变为橡胶的试样，如果在室温下放置较长的时间，又能恢复拉伸前的塑料性质。