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971.
972.
电子垃圾拆解所引起的环境问题已经受到广泛关注,根据联合国环境规划署统计,全球约70%的电子垃圾通过各种途径进入我国,而我国自身也产生大量的电子垃圾。我国电子垃圾拆解活动采用的工艺较为原始,位于广东的贵屿和浙江的台州是我国最大的两个电子垃圾拆解地,拆解过程中电子垃圾本身含有和不当处置所产生的大量持久性有毒化学污染物(如重金属、二 NFDA1 英类、溴代阻燃剂等)释放到环境中,对拆解地生态系统及居民健康造成严重的威胁。本文重点针对我国电子垃圾拆解所造成的持久性有毒污染物(PTS)污染现状、管理措施和法规、拆解区居民所面临的持久性有毒污染物暴露健康风险及其相关研究最新进展进行了分析和概括,并对电子垃圾拆解区域持久性有毒污染物及新型环境污染物研究和发展方向作了展望。 相似文献
973.
Li-Na Wang Huan-Huan Zhang Lin Xu Bin-Yuan Liu Tong-Fei Shi Shi-Chun Jiang Li-Jia An 《高分子科学》2018,36(8):984-990
We have investigated the influence of the adsorption process on the dewetting behavior of the linear polystyrene film(LPS),the 3-arm star polystyrene film(3 SPS) and the ring polystyrene film(RPS) on the silanized Si substrate.Results show that the adsorption process greatly influences the dewetting behavior of the thin polymer films.On the silanized Si substrate,the 3 SPS chains exhibit stronger adsorption compared with the LPS chains and RPS chains; as a result,the wetting layer forms more easily.For LPS films,with the decrease of annealing temperature,the kinetics of polymer film changes from exponential behavior to slip dewetting.As a comparison,the stability of 3 SPS and RPS films switches from slip dewetting to unusual dewetting kinetic behavior.The adsorbed nanodroplets on the solid substrate play an important role in the dewetting kinetics by reducing the driving force of dewetting and increase the resistant force of dewetting.Additionally,Brownian dynamics(BD) simulation shows that the absolute values of adsorption energy(ε) gradually increase from linear polymer(-0.3896) to ring polymer(-0.4033) and to star polymer(-0.4264),which is consistent with the results of our adsorption experiments. 相似文献
974.
Protein-protein interactions are attractive but challenging targets for drug discovery. Recent technological progress and examples using macrocyclic peptides as protein interaction modulators are reviewed. 相似文献
975.
In this paper, we propose a physical scheme to realize quantum SWAP
gate by using a large-detuned single-mode cavity field and two
identical Rydberg atoms. It is shown that the scheme can also be used
to create multi-atom cluster state. During the interaction between
atom and cavity, the cavity is only virtually excited and thus the
scheme is insensitive to the cavity field states and cavity decay.
With the help of our scheme it is very simple to prepare the $N$-atom
cluster state with perfect fidelity and probability. The practical
feasibility of this method is also discussed. 相似文献
976.
977.
Xue DJ Xin S Yan Y Jiang KC Yin YX Guo YG Wan LJ 《Journal of the American Chemical Society》2012,134(5):2512-2515
Germanium is a promising high-capacity anode material for lithium ion batteries, but it usually exhibits poor cycling stability because of its huge volume variation during the lithium uptake and release process. A double protection strategy to improve the electrode performance of Ge through the use of Ge@C core-shell nanostructures and reduced graphene oxide (RGO) networks has been developed. The as-synthesized Ge@C/RGO nanocomposite showed excellent cycling performance and rate capability in comparison with Ge@C nanoparticles when used as an anode material for Li ion batteries, which can be attributed to the electronically conductive and elastic RGO networks in addition to the carbon shells and small particle sizes of Ge. The strategy is simple yet very effective, and because of its versatility, it may be extended to other high-capacity electrode materials with large volume variations and low electrical conductivities. 相似文献
978.
A novel rolling circle amplification (RCA) immunoassay based on DNA enriching magnetic nanoparticles and assembled fluorescent DNA nanotags, magnetic nanoparticles-RCA immunoassay, is developed as a versatile fluorescence assay platform for highly sensitive proteins detection. 相似文献
979.
Learning from nature has inspired the creation of intelligent devices to meet the increasing needs of the advanced community and also to better understand how to imitate biology. As one of biomimetic nanodevices, nanochannels or nanopores aroused particular interest because of their potential applications in nanofluidic devices, biosensing, filtration, and energy conversions. In this review we have summarized some recent results mainly focused on the design, construction and application in energy conversion systems. Like biological nanochannels, the prepared smart artificial nanochannels fabricated by ion track-etched polymer membranes and smart molecules show a great potential in the field of bioengineering and biotechnology. And these applications can not only help people to know and understand the living processes in nature, but can also inspire scientists to study and develop novel nanodevices with better performance for the mankind. 相似文献
980.
The essential oil of the aerial parts of Amethystea caerulea L. was obtained from steam distillation and investigated by GC and GC-MS. The main components of the essential oil were morrilol (25.1%), 4-vinylguaiacol (14.3%) and acetoanisole (14.3%), followed by linalool (6.6%), eugenol (5.8%) and α-caryophyllene (5.2%). The essential oil showed pronounced contact toxicity against Drosophila melanogaster L. and maize weevil, Sitophilus zeamais (Motsch.), with LD(50) values of 5.18 and 50.45?μg per adult, respectively. The essential oil also possessed strong fumigant toxicity against the maize weevils with an LC(50) value of 25.39?μg?mL(-1). 相似文献