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搜索结果: 1-15 共查到理学 PAN相关记录47条 . 查询时间(0.239 秒)
PAN作为NOx和自由基的临时储存库,可以运输到偏远地区以重新分配NOx,并在区域甚至全球范围内通过影响NOx和自由基分布以干预O3的生成机制。近地层O3浓度升高会增强大气氧化能力,并对全球气候变化、生态系统和人类健康产生有害影响。在对流层中,PAN的含量远低于O3,但其生物毒性却比O3高一到两个数量级。为有效控制对流层光化学污染,探索光化学机理和污染形成的控制因素,以及判断PAN对O3的影响对科...
近日,中国科学院城市环境研究所陈进生研究团队在大气过氧乙酰硝酸酯(PAN)光化学污染机制认识方面取得进展。研究结果以“Characteristics of peroxyacetyl nitrate (PAN) in a coastal city of southeastern China: photochemical mechanism and pollution process”为题目发表在环境...
The pan-sharpening is a widely used operation in remote sensing image processing, this operation aims at combining an observable high spatial resolution panchromatic image with a multispectral one, to...
将盐酸羟胺与聚丙烯腈(PAN)反应得到偕胺肟化聚丙烯腈(AOPAN)溶液,随后采用同轴静电纺丝技术,制备了以AOPAN为壳,PAN为芯的同轴纳米纤维(AOPAN@PAN).通过透射电子显微镜(TEM)、扫描电子显微镜(SEM)和红外光谱(FTIR)等对纤维的形貌、组成和力学性能进行了表征.结果表明
将静电纺丝法制备的聚丙烯腈(PAN)纳米纤维膜用不同比例的盐酸羟胺和水合肼混合溶液改性,再与Fe3+离子进行配位反应,制备了5种不同表面结构的改性PAN纳米纤维铁配合物;考察了水合肼加入量对纤维铁配合物的制备及对偶氮染料活性红195去除能力的影响. 结果表明,随着水合肼加入量的增大,改性PAN纳米纤维的直径减小且其铁配合物表面的铁离子配合量降低;3种混合改性PAN纳米纤维铁配合物均对活性红195具...
This is an annual conference focused on exciting recent developments in number theory and related subjects, especially those occurring in the greater Asian regions or by mathematicians of Asian descen...
The pyromellitic dianhydride (PMDA) crosslinked poly(vinyl alcohol) (PVA) was coated on top of the PAN ultrafiltration membrane to form a PVA/PAN composite PV membranes for wastewater desalination. Th...
The Pan-STARRS project at the University of Hawaii Institute for Astronomy is publicly releasing the world's largest digital sky survey today, via the Space Telescope Science Institute (STScI) in Balt...
Top-of-atmosphere (TOA) spectrally resolved shortwave reflectances and long-wave radiances describe the response of the Earth's surface and atmosphere to feedback processes and human-induced forcings....
The Kabye and Kpaza Massifs correspond to two main granulitic suites in the suture zone of the Pan-African Dahomeyide orogenic belt, in northern Togo. The Kabye Massif is composed of an important west...
采用红外光谱、X射线能谱、激光显微共焦拉曼光谱、X射线衍射光谱和电子自旋共振等多种表征手段,定量探讨了热氧稳定化气氛中氧气浓度与聚丙烯腈纤维的径向结构转变以及与碳纤维结构和性能的关联.结果表明,随着氧气浓度的增大,氧气自皮层逐渐扩散到纤维内部,热氧稳定化纤维的径向结构趋于均质化.当热氧稳定化过程氧体积浓度(Vo)由20.38%增加到21.15%时,热氧稳定化纤维的皮芯结构逐渐减小,环化程度增幅显著...
Geochemical and geochronological studies have been carry out on the leucosomes of Yaoundé series with the aims to identify the magma sources and to indicate their production periods and emplacement wi...
We have searched ~8200 sq. degs for high proper motion (~0.5-2.7"/year) T dwarfs by combining first-epoch data from the Pan-STARRS1 (PS1) 3-Pi Survey, the 2MASS All-Sky Point Source Catalog, and the W...
We present the discovery of two ultra-luminous supernovae (SNe) at z ~ 0.9 with the Pan-STARRS1 Medium-Deep Survey. These SNe, PS1-10ky and PS1-10awh, are amongst the most luminous SNe ever discovered...
We determine enhancement ratios for NOx, PAN, and other NOy species from boreal biomass burning using aircraft data obtained during the ARCTAS-B campaign and examine the impact of these emissions on t...

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