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压在稚嫩的身体上耕耘-遭遇现实考量
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压在稚嫩的身体上耕耘-遭遇现实考量

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压在稚嫩的身体上耕耘-遭遇现实考量24小时售后电话-总部预约热线400客户报修中心

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  微观世界“精灵”,应用潜力无限——

  纳米材料能带来哪些颠覆性技术(瞰前沿)

  “实现原子级特征尺度与可重构光频相控阵的纳米激光器”入选2024年度“中国科学十大进展”,我国科研团队研发的纳米机器人可为患者清除血栓……小小纳米,潜力无限,在微观世界迸发推动科技发展的动能。

  从我们身边应用荷叶原理制作的防水涂层服饰,到纳米药物、纳米传感器等,纳米科技正在各个领域里“以小博大”、改变生活。未来,纳米功能材料还将助力“太空电梯”等科幻场景变为现实。本期“瞰前沿”,让我们走进纳米小世界,看见更加广阔的科技未来。

  ——编者

  微观“精灵”

  展现惊人性能

  在刘慈欣的科幻小说《三体》中,名为“纳米飞刃”的神奇材料令人印象深刻——一种极其纤细的透明丝线,能够轻松将一艘巨轮切割成无数薄片。这看似科幻的情节,其实离我们并不遥远。纳米功能材料——这一微观尺度上的“精灵”不仅活跃在科技前沿,也在改变我们的生活。

  纳米是一个长度单位,1纳米等于十亿分之一米。物质被“切割”到纳米级别时,会展现出与宏观尺度时截然不同的特性。原本导电的金属深入到纳米尺度后,会逐渐变成半导体进而变成绝缘体;当尺寸进一步减小时,表现出量子效应,又变成了导体。在微观世界里,纳米功能材料会呈现宏观量子隧道效应、表面效应、小尺寸效应等神奇性质。

  科幻源自现实,《三体》中的“纳米飞刃”,有自己的原型——碳纳米管。这种由碳原子组成的管状结构,强度是钢的100倍,却比碳纤维还细。目前的碳纳米管,虽然无法像小说里描述的那样成为削铁如泥的利器,但在实验室里,我国科学家研发的单根结构完美的碳纳米管纤维,可以吊起一头成年亚洲象;在产业应用方面,利用流化床技术,工厂里已经生产出用于新能源车的万吨级多壁碳纳米管导电浆料;未来,利用碳纳米管,还可以制造碳基芯片、工业催化剂、显示屏、X射线管等。

  其实,纳米功能材料也并非全是人工合成,在大自然中也有这些微观“精灵”的身影——荷叶表面的纳米级乳突结构,能够让水珠滚落时不留痕迹;蝴蝶翅膀能随光线变化呈现不同色彩,也是因为翅膀上的纳米结构;我们牙齿表面的牙釉质,也是由纳米级的羟基磷灰石晶体构成,这使得牙釉质具有极高的坚固度和耐磨性……这些天然纳米功能材料,在漫长的历史进化中展现出惊人性能。

  特性“变身”

  在纳米尺度施展“魔法”

  当物质维度缩小至纳米量级,仿佛被施加了某种“魔法”,其固有属性会发生颠覆性变化,这种由尺度剧变引发的奇异现象,既为科研探索打开新维度,也为技术应用开辟新路径。

  物质本征特性的变化在声、电、光、磁、力等方面都很显著。例如,在宏观尺度下,金需要1064摄氏度高温方能熔化,在其粒径缩减至2纳米时,其熔点竟骤降至约327摄氏度,这为冶金工艺节能增效提供了全新思路。光学性质的重构更具视觉冲击力——宏观尺度下,铜呈现典型的紫红色金属光泽,在纳米尺度下竟然变为深邃的黑色。除了变色,原本化学性质稳定的金属铜,在纳米化后具有自燃特性,呈现前所未有的反应活性。

  特性“变身”,正改写多个领域的技术范式。经特殊处理的纳米活性炭,其比表面积较传统材料实现数量级跃升,吸附容量增长10倍以上,成为净水系统中重金属与有机污染物的“捕手”;基于纳米隐身涂层,可在特定频段实现雷达波的隐身,在国防安全领域有重要作用。

  在纳米尺度构筑功能结构,研究人员需依赖原子力显微镜、聚焦离子束刻蚀系统等尖端设备,在埃米级精度下实现材料组装。当物质进入纳米王国,其展现的奇异特性正在催生一批颠覆性技术,驱动人类认知与工程实践向更微观尺度的纵深挺进。

  日常应用

  多个领域大有可为

  纳米功能材料并非摆在实验室里的“花瓶”,它们正在各个领域大显神通。

  当纳米科技与医疗领域深度融合,人类对抗疾病就有了新“武器”。纳米药物如同精确制导导弹,通过表面修饰的靶向分子精准识别癌细胞特有的生物标记物,将药物直接输送至病灶核心。在临床中,淋巴示踪剂以纳米活性炭为基底,能在术前清晰勾勒出肿瘤边界,为外科医生提供三维导航;而纳米脂质体包裹的化疗药物,则能突破肿瘤血管屏障,在靶区将药物浓度提升数十倍,显著增强疗效的同时降低全身毒副反应。实验室里的纳米机器人更具未来感,可以用于血液循环系统巡航,实时清除血管沉积物,甚至对受损细胞进行纳米级手术修复,为癌症治疗开辟全新范式。

  能源领域,锂离子电池中碳纳米管构建的三维导电网络,为电极材料获得电子带来一条“高速公路”,充电速度以指数级提升。不仅如此,纳米改性电池还可以通过石墨烯散热涂层在冬天实现热量二次利用,突破续航瓶颈。在安全防护方面,纳米隔热涂层具有热屏障性能,即便电池遭遇极端热失控,也能维持15分钟左右的结构完整,为车祸逃生争取宝贵时间。

  纳米尺度上的信息产业也大放光彩:当光刻机突破2纳米工艺节点,指甲大小的芯片内晶体管数量突破百亿大关,算力洪流驱动着人工智能、物联网等前沿领域跨越式发展,与之并行的纳米传感器技术,正将环境监测与健康管理推向实时精准的新阶段。

  未来应用

  重塑人类探索的边界

  纳米功能材料拥有广阔的应用前景,纳米技术正在重塑人类感知与探索的边界。

  在AR(增强现实)领域,纳米光波导技术正将科幻场景变为现实。AR眼镜采用纳米级光波导镜片,重量仅几十克却拥有超过80度的视场角,透过镜片,用户可体验信息获取、导航、翻译等功能。镜架上集成的纳米天线阵列,在厘米级空间内构建起高速通信通道,使设备摆脱线缆束缚,真正融入智能生活场景。

  智能穿戴设备在纳米技术加持下正突破形态与能源限制。纳米柔性屏采用可拉伸的银纳米线电极,使智能手表能像皮肤般贴合腕部;纳米发电机技术利用氧化锌纳米线在机械形变中产生的压电效应,可以将人体运动能转化为电能。

  当人类将目光投向星辰大海,纳米材料展现出前所未有的应用潜力。碳纳米管构成的太空电梯缆绳,理论强度可达钢材的百倍,使未来低成本天地运输成为可能。而纳米防护层技术则为航天器披上了“铠甲”:纳米气凝胶的多孔结构既能阻隔太空极低温,又能耐受返回舱再入大气层时的超高温;纳米复合涂层通过多层界面反射机制,将宇宙辐射剂量降低3个数量级,为深空探测生命保障系统提供关键解决方案。

  从日常穿戴到探索太空,从《三体》中的“纳米飞刃”到现实中的纳米机器人、纳米电池等,纳米功能材料正在以惊人的速度改变着我们的世界。让我们期待,这些微观世界里的“魔法道具”,能带来更多惊喜!

  任红轩作者为国家纳米科学中心成果转化处处长、正高级工程师

  学术支持:中国科学技术协会、国家纳米科学中心

  (人民日报)

  巴黎4月19日电当地时间4月18日,中国驻巴黎旅游办事处携手中国动画电影《哪吒之魔童闹海》(以下简称《哪吒2》)的法国发行方TrinityCineAsia与Borui公司,在巴黎大雷克斯影院举办“你好!中国”旅游推介活动暨《哪吒2》法国首映礼。

  北京4月19日电(记者陈杭)19日,2025北京亦庄半程马拉松暨人形机器人半程马拉松赛场上,来自北京亦庄的“天工Ultra”以2时40分42秒的成绩冲线,夺得全球首个人形机器人半程马拉松赛事桂冠。

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