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来源：大发彩票论坛2024-04-09 17:48

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竹子“变身”高透光电磁屏蔽材料******

　　竹材是一种常见的生物质材料，具有可持续性、生长速度快、资源丰富等优点，被广泛用于家具制造及家居装饰用材领域。但是，你见过透光竹材吗？它不仅透光还可以隔热、保温、屏蔽电磁，这样神奇的材料是怎么制成的呢？

　　近日，南京林业大学家居与工业设计学院吴燕教授领衔的课题组，通过一种简单高效的处理方式，将竹材转化为具有良好光学性能的透光原竹和透明竹片，同时保留了原竹天然形状和纤维素骨架结构。日前，相关研究论文发表于国际期刊《纳微快报》。

　　科技创新将竹材利用最大化，竹材逐渐作为木材、塑料、钢筋等材料的替代品被开发利用，形成了重组竹、竹编工艺品、竹纤维制品、竹碳制品等100多个系列上万个品种，竹材产品已经覆盖生产生活的各个领域。我国是世界竹材产品生产、贸易第一大国，2020年，全国竹产业产值近3200亿元。

　　随着人们对家居环境个性化装饰需求的日益增多，将竹材等环保材料转化为新型材料的研究越来越多，吴燕课题组的研究便是其中之一。

　　论文第一作者王晶介绍，透光竹材的制备主要分为两个步骤，第一步是去除发色基团，第二步是浸渍折射率与竹纤维素模板相同的聚合物。

　　由于竹材的孔隙率较低，竹材去除木质素和浸渍聚合物的时间比巴沙木、杨木等密度较小的木材要长，因此制备具有一定厚度的透光竹材是一项挑战。

　　该课题组选取5年生毛竹为原材料，将去青后的原竹浸泡在过氧化氢和乙酸混合溶液中，再利用简单的化学预处理脱除原竹中的木质素，木质素的去除会导致更多孔隙出现，有利于下一步的填充过程。最后向竹纤维素模板中填充折射率指数与其相匹配的树脂，再经过快速固化工艺，一款具有优异光学传输性能、抗拉伸性能、表面装饰性和美学价值的透光竹材便应运而生了。与其他不同聚合物浸渍方法制备的生物质透明样品相比，透光原竹固化时间非常短，因此显示出显著的快速制备加工潜力。

　　“此类将原竹直接加工成竹纤维素模板再合成透明材料的方法，将大大减少前期原料机械加工和后期原料成型的步骤，不仅减少了能耗，也减少石化资源的浪费。”吴燕说。同时，这个方法还可以用于处理其他高密度、低孔隙率的生物质材料。

　　据介绍，透光竹材的壁厚可达6.23毫米，透光率约60%，照度为1000勒克斯，吸水质量变化率小于4%，纵向抗拉强度达到46.40兆帕，表面性能为80.2HD（布氏硬度计测试出来的硬度单位）。

　　吴燕教授领衔的课题组将透光原竹与透明竹片、电磁屏蔽膜组成一款复合器件，整体结构类似于常见的蜂窝板，其中透光原竹充当核心骨架、透明竹片为面板、锡掺杂氧化铟薄膜为功能层。

　　经过研究发现，这款复合器件可表现出显著的隔热、保温性能以及电磁屏蔽性能，在家居与建筑装饰材料领域具有广阔前景。（记者张晔通讯员方彦蘅姚会春）

中新网评：处理核污水绝不是日本自家私事******

　　中新网北京1月19日电(蒋鲤)日本政府近日称，将于2023年春夏期间开始向海洋排放经过处理的福岛第一核电站核污水。日本罔顾国内民众及周边国家的屡屡反对，企图将核污水“一倒了之”，把一件关乎全球海洋生态环境和公众健康的事当成了自家私事。

资料图：日本福岛第一核电站。

　　2011年，福岛核电站事故发生后，大量放射性物质泄漏到大气层和太平洋，对周围环境造成了难以逆转的伤害，数十万人被迫撤离该地区。时至今日，作为日本邻国之一的韩国仍未解除福岛海鲜禁令。

　　日本以核污水存储能力即将达到上限为由，在2021年4月13日，正式决定将福岛第一核电站核污水排入太平洋。过去一年多，日本政府和东京电力公司一直在持续推进核污水排海计划。

　　日本政府辩称，这些核污水经多核素处理系统(ALPS)处理后很安全，甚至“可以喝”，这样的表态无疑在愚弄大众。

　　事实上，经过处理的核污水仍含有多种放射性物质，核污水一旦排放入海就无法回收，长期来看，将会给海洋生态带来难以估量的潜在威胁，最终危害人类健康。

　　因此，核污水排海计划推出后，遭到日本民众强烈反对。日本《朝日新闻》2022年3月公布的问卷调查显示，福岛县、宫城县和岩手县受访的42个市町村长中，约六成反对东京电力公司福岛第一核电站核污水排放入海。日本全国渔业协会联合会也多次申明立场，反对该计划。

　　日本政府认为，核污水排海是最便宜、最省事的解决方案，但此举却将周边国家乃至全世界置于核污染风险中。太平洋非日本一家之海，核污水会随着洋流流动，其影响势必会跨越国界，危害周边国家乃至整个国际社会的公共福祉和利益。

　　《韩国经济新闻》发文称，相关研究认为，福岛核污水如果排放入海，约7个月后将到达济州等韩国海域，该国水产业和旅游业将遭受相当大的损失。

　　德国南极海洋机构也曾发出警告，若日本将所有核污水排入海中，不到半年，整个太平洋都将面临高度辐射威胁，包括远在大洋另一端的美国。太平洋地区人民更是对日本该计划持反对意见。

　　日本作为《联合国海洋法公约》缔约国，有义务保护海洋环境。然而，在核污水排海方案的正当性、核污水数据的可靠性、净化装置的有效性、环境影响的不确定性等问题上，日本未能作出科学、可信的说明。

　　国际原子能机构技术工作组虽已三次赴日实地考察评估，但尚未就日排海方案的安全性给出结论，并且对日本提出诸多澄清要求和整改意见。在此情况下，日本仍执意推进核污水排海工程建设，这是极不负责任的行为。

　　太平洋不是日本的下水道，日本必须正视各方合理关切，在与周边国家等相关利益方和国际原子能机构充分协商后，制定合理的核污水处理方案。日本也要着眼长远，若只顾眼前，执意将核污水排放入海，不仅其自身，周边国家乃至全世界都将为之买单，其后果必将会危害数代人。

　　Fukushima water disposal by no means Japan’s own business

　　By John Lee

　　(ECNS) -- Japan has announced it will release treated wastewater from the wrecked Fukushima Daiichi Nuclear Power Plant into the Pacific Ocean this year.

　　Although Fukushima wastewater disposal affects global marine ecological environment protection and public health, Japan has turned a deaf ear to domestic and international opposition to dumping the contaminated water into the sea, treating the "global" matter as its own business.

　　The Fukushima accident in 2011 had sent large quantities of radiation into the atmosphere and the Pacific Ocean, causing irreversible damage to the surrounding environment, and hundreds of thousands of people were forced to evacuate the area. South Korea still maintains its import ban on Japanese seafood from areas affected by the Fukushima nuclear disaster.

　　On April 13, 2021, Japan announced it had decided to discharge contaminated radioactive wastewater in Fukushima Prefecture into the sea due to dwindling storage space, with the Japanese government and plant operator Tokyo Electric Power Company Holdings Inc. promoting the release plan over the past year.

　　The Japanese government argues that the water treated by an advanced liquid processing system, or ALPS, is safe and drinkable, which is undoubtedly fooling the public.

　　In fact, the treated wastewater still includes a variety of radioactive substances and can’t be recycled once discharged into the sea, which will pose a great threat to marine ecology and ultimately endanger human health in the long run.

　　Therefore, the discharge plan has been strongly opposed in Japan. According to a questionnaire conducted by The Asahi Shimbun, nearly 60 percent of mayors of 42 municipalities in Iwate, Miyagi and Fukushima prefectures oppose the discharge plan. The National Fisheries Cooperative Federation of Japan has also repeatedly stated its opposition in public.

　　The Japanese government believes that dumping Fukushima wastewater into the sea is the cheapest and most convenient solution, but neighboring countries and even the whole world will be at risk of nuclear pollution.

　　The Pacific Ocean doesn’t belong to Japan and the wastewater flow along oceanic currents will surely break boundaries and endanger public welfare and the interests of neighboring countries and even the international community.

　　The Korea Economic Daily reported that related research concluded that if contaminated water from Fukushima is released into the ocean, it would only take seven months for the contaminated water to reach the shores of Jeju Island, with the country's aquaculture and tourism suffering considerable losses.

　　According to the calculation of a German marine scientific research institute, radioactive materials will spread to most of the Pacific Ocean within half a year from the date of discharge, and the U.S. and Canada will be affected by nuclear pollution. People in the Pacific region also oppose the discharge plan.

　　As a participant of the United Nations Convention on the Law of the Sea, Japan has the obligation of protecting the marine environment.

　　However, it hasn’t offered a full and convincing explanation on issues like the legitimacy of the discharge plan, the reliability of data on the nuclear-contaminated water, the efficacy of the treatment system or the uncertainty of environmental impact.

　　Though the IAEA has yet to complete a comprehensive review after three investigations in Japan, the Japanese side has been pushing through the approval process for its discharge plan and even started building facilities for the discharge. It is rather irresponsible for Japan to act against public opinion at home and concerns abroad.

　　The Pacific Ocean is not a private Japanese sewer. The country must seriously heed the voices of the international community and make a reasonable plan for the Fukushima wastewater disposal after full consultation with stakeholders and international agencies.

　　If it only seeks instant interest and insists on discharging the contaminated water into the sea, not only itself, but also its neighboring countries and the entire world will pay for the decision and several generations will be forced to bear the consequence.