Second Skin
Although soldiers don special suits and masks1) to protect their skin and airways from toxic2) chemicals,these defenses are uncomfortable and don't provide sufficient protection against biological weapons.So the Defense Advanced Research Projects Agency challenged Da Ingber,scientific founder of Molecular Geodesics Inc.in Cambridge,Massachusetts,to come up with3)an alternative4).
One of the problems with existing suits,says Ingber,is that they are too much like raincoats--that is,they prevent body heat from dissipating5) into the air.Another issue:Existing suits don't allow the freedom of movement needed to perform such tasks as loading and firing weapons.
To create a better material,the company is testing different structures based on an architectural principle.
Since a pathogen6) is most likely to enter the body via7) the nose and mouth,the company is also devising materials for face masks that filter pathogens and allow soldiers to breathe normally.Existing masks feel like breathing through a blanket while exercising,says Ingber.The ideal material would mimic the porosity of biological cells to allow air in,while selectively filtering out hazardous8) pathogens.The company is presently testing a prototype9) materials.
第二種皮膚
所謂的“第二種皮膚”,就是仿生皮膚。這種“皮膚”實則是一種近似人體“皮膚”的防生物武器的衣服,它的質(zhì)地結(jié)構(gòu)具有生物細胞的多孔性,但比生物的“皮膚”更勝一籌,因為它還能選擇性地將外界有害病原菌阻隔在體外。美國研制這種“皮膚”已有很長時間,目的是防御生物武器。由此制成的防毒服,還可以保證士兵投彈和射擊活動的自如。“9.11”事件后,美國的行政部門不斷收到能引起炭疽病的孢子郵寄物。很顯然,這種防生物武器的材料的研制步伐會因此而大大加快。這篇文章講述了這種“皮膚”的一些性能,并未透露其材料的化學構(gòu)成如何。但對國防事業(yè)無疑具有重要意義。
雖然士兵身穿特殊服裝、頭戴面罩,以保護他們的皮膚,防止空中的有毒化學物質(zhì),但是這些防御措施令人不適,而且也無法充分防御生物武器。所以,國防高級研究計劃署向丹·因格博(馬薩諸塞州坎布里奇分子測量公司的科學奠基人)提出研制替代品的新課題。
因格博說,現(xiàn)在的防毒服存在的問題之一是,它們太像雨衣,也就是說它們阻止了體溫散出來。另一個問題是:現(xiàn)在的防毒服阻礙了像投彈和射擊這類任務(wù)所需的自由活動。
為了制造一種更好的材料,該公司正在檢測不同物質(zhì)的結(jié)構(gòu),性能是以建筑學原理為基礎(chǔ)的。
由于病原菌極大可能是通過鼻腔和口腔進入人體,該公司還在設(shè)計能過濾病原體的面罩材料,以使士兵能正常呼吸。因格博說,現(xiàn)有的面罩一運動就會感到像透過毯子呼吸。理想的材料應(yīng)該是摹仿生物細胞的多孔性,使空氣能吸入,并選擇性地濾出有危險性的病原菌。該公司現(xiàn)在正在測定這種樣品材料。
NOTE 注釋:
1. mask [mB:sk] n. 面具,面罩
2. toxic [5tCksik] adj. 有毒的, 中毒的
3. come up with 提出,拿出
4. alternative [C:l5tE:nEtiv] n. 課題,可供選擇的事物
5. dissipate [5disipeit] v. 驅(qū)散, (使)(云、霧、疑慮等)消散
6. pathogen [5pAWEdV(E)n] n. [微生物]病菌, 病原體
7. via [5vaiE, 5vi:E] prep. 經(jīng), 通過, 經(jīng)由
8. hazardous [5hAzEdEs] adj. 危險的, 冒險的
9. prototype [5prEutEtaip] n. 原型