A US-based team of scientists claims to have invented a material that releases over two weeks of night-vision light after just one minute's exposure to the sun.
The University of Georgia team says the near-infrared emitting substance could offer the military "secret" illumination at nighttime.
It says the all-weather material could also revolutionise diagnostic medicine.
The details are published in the latest issue of the Nature Materials journal.
The scientists tested this material in a variety of conditions and found it could be rapidly and repeatedly charged even if the day was cloudy, overcast or rainy.
The team said the phosphorescent substance did not need to be exposed to direct sunlight. It took on a charge in shadows, underwater or even submerged in a corrosive bleach solution. Fluorescent lights also activated the process.
Lead author, Zhengwei Pan, said the material could be added to ceramic discs or mixed into paints and inks by the army and others.
"The military and security services could use this for identification purposes - either to locate people or equipment in the night so that only people with night vision goggles could see them", Prof Pan told the BBC.
"We are also experimenting with nanoparticles of the substance to see if we can bind them to cancer cells to help researchers and doctors identify them."
Prof Pan said the substance could also help develop next-generation solar energy cells thanks to its efficiency at collecting and storing sunlight.


据英国广播公司（BBC）11月21日报道，来自美国的一个科学家团队近日宣称，他们已经发明出了一种新的材料，只要放在阳光下一分钟，就可以连续超过两周释放出夜视光。
这支来自乔治亚大学的团队说，近红外发光物质可以在夜间提供军事"机密"。

据称，这种全天候的夜光材料还能够促进诊断医学的革新。
研究详情发表在最新一期的《自然材料》杂志（《自然》子刊）上。
科学家在不同的条件下对这种材料进行了测试，发现即使是在阴天、多云天气或是雨天，它也能够迅速、重复地补充能量。

科研小组表示，这种磷光性的物质不需要放在阳光下直射。在阴影中、水下甚至是淹没在漂白粉溶液里它都可以补充能量。荧光灯照射也能激活补充能量的过程。

研究报告的主要作者潘正伟（音译）表示，这种材料可以被用于陶瓷电容器上，也可以将其与涂料和油墨混合供军队和其他机构使用。

"军队和安全服务部门可以使用这种材料来达到识别的目的--在夜间定位人员或者设备，这样一来，就只有戴了夜视镜的人能够看见他们了"，潘教授告诉记者。

"我们还对这种物质的纳米粒子进行了实验，看是否能将其与癌细胞联系起来，来帮助研究人员和医生确认癌细胞的存在。"

潘教授说，由于这种物质在收集和储存阳光方面的效率，它还将有助于开发新一代的太阳能电池。

• variety [və´raiəti] n.变化；多样(性)；种类 (初中英语单词)
• sunlight [´sʌnlait] n.日光 (初中英语单词)
• charge [tʃɑ:dʒ] v.收费；冲锋 n.费用 (初中英语单词)
• solution [sə´lu:ʃən] n.解答；解决；溶解 (初中英语单词)
• security [si´kjuəriti] n.安全；证券；抵押品 (初中英语单词)
• equipment [i´kwipmənt] n.装备，设备 (初中英语单词)
• vision [´viʒən] n.视觉；想象力；幻影 (初中英语单词)
• cancer [´kænsə] n.癌；毒瘤 (初中英语单词)
• identify [ai´dentifai] vt.认出；鉴定；验明 (初中英语单词)
• energy [´enədʒi] n.活力，精力；能力 (初中英语单词)
• exposure [ik´spəuʒə] n.暴露；曝光(时间) (高中英语单词)
• georgia [´dʒɔ:dʒjə] n.乔治亚 (高中英语单词)
• efficiency [i´fiʃənsi] n.效力；效率；有能力 (高中英语单词)
• repeatedly [ri´pi:tidli] ad.反复地；再三地 (英语四级单词)
• bleach [bli:tʃ] v.漂白；变白 (英语四级单词)
• illumination [i,lju:mi´neiʃən] n.照明；阐明 (英语六级单词)