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91.
城市雨水径流水质监测及影响因素 总被引:2,自引:0,他引:2
实现城市雨水资源化利用是改善城市生态环境的有效措施,雨水水质控制是现代城市雨水利用的重要组成部分和主要特征.通过对城区屋面雨水、院区雨水、市区道路雨水3种下垫面下的径流水质进行监测,分析了径流污染物随降水的变化过程,并对其影响因素进行了简要分析,同时提出了院区雨水水质控制措施,为城市雨水利用提供了决策基础. 相似文献
92.
This note establishes a new method that can measure interface dilatation elastic module (e) and dilatation viscosity (d) of all surfactants based on the surface pressure relaxation process. The wide applicability was proved with the stability of foam as an example. 相似文献
93.
The two-step monsoon changes of the last deglaciation recorded in tropical Maar Lake Huguangyan, southern China 总被引:3,自引:0,他引:3
Wenyuan Wang Jiaqi Liu Dongsheng Liu Tungsheng Liu Ping’an Peng Houyuan Lu Zhaoyan Gu Guoqiang Chu J. Negendank Xiangjun Luo J. Mingram 《科学通报(英文版)》2000,45(16):1529-1532
The concentrations of biogenic silica, total organic carbon, total nitrogen and total hydrogen inferred from the sediments
of tropical Maar Lake Huguangyan, southern China, provide a climate record of the last déglaciation with century resolution.
The records fully demonstrate the existence of the two-step shape of the last déglaciation in tropic East Asia, and they point
out noticeable differences between the low and high latitudes in the Northern Hemisphere. Thus, the Boiling first warming
at the last deglaciation in the low latitude may have preceded that of the high latitude, whereas the cooling of the Younger
Dryas occurred synchronously in the two regions. These results likely suggest that the links between the low and high latitude
climates in the Northern Hemisphere during this period are complexity. 相似文献
94.
Chengyin Wu Yijia Xiong Zhen Gao Fan’ao Kong Haihe Lu Xiaodong Yang Zhizhan Xu 《科学通报(英文版)》2000,45(21):1953-1955
Photoionization and photodissociation of CH3CN were studied by a linear time of flight mass spectrometer coupled with 800 nm, 50 fs laser pulses at intensities of 6.3×1013-1.2×1014 W/cm2. The laser power dependences for principal ions CH3CN+, CH2CN+, CHCN+ and CCN+ were measured, which are consistent with the numbers of photons required to produce the ions via multiphoton ionization and dissociation. The results show that eight-photon non-resonant multiphoton ionization is the main photoionization mechanism of the parent ion CH3CN+, while the fragment ions were produced through the dissociation of the molecules in the super-excited states. 相似文献
95.
聚氨酯/聚甲基丙烯酸甲酯/有机蒙脱土纳米复合材料的结构、形态与力学性能 总被引:6,自引:1,他引:5
将插层纳米复合技术与同步互穿聚合物网络(IPN)技术相结合,制备了聚氨酯(PU)/聚甲基丙烯酸甲酯(PMMA)/有机蒙脱土(OMMT)纳米复合材料.用XRD,SEM,TEM等手段并通过力学性能测试研究了该复合材料和相应的PU/PMMA-IPN材料的结构、形态和力学性能.结果表明,PU/PMMA/OMMT纳米复合材料中一部分蒙脱土以8~20nm厚、50~200nm长的片层有序地分布在聚合物基体中,形成了插层/剥离型纳米复合材料,其力学性能显著优于相应的PU/PMMA-IPN材料.OMMT易与PU/PMMA/OM-MT体系中的PU硬段及PMMA分子链形成氢键结合,使得OMMT,PU,PMMA彼此之间的相互作用加强,相容性改善,导致体系的力学性能显著提高.文中还研究了OMMA添加量、PU/PMMA质量比、过氧化二苯甲酰(BPO)添加量、二甲基丙烯酸乙二酯(EGDMA)添加量、1,4丁二醇(BDO)系数等因素对PU/PMMA/OMMT纳米复合材料力学性能的影响,获得PU/PMMA/OMMT纳米复合材料的最佳制备条件为:PU/PMMA质量比为60/40,OMMT,BPO和EGDMA添加量分别为MMA单体质量的5.0%,0.80%和2.0%,BDO系数为0.80. 相似文献
96.
杨飒 《河南教育学院学报(自然科学版)》2005,14(3):35-36
通过对电子线路实验中存在的几个典型问题的分析,讨论测试仪器频率特性给实验带来的局限性和测量误差,并提出了消除这种测量误差的解决方案. 相似文献
97.
建立了青杨(Populus cathayana)组织培养系统.最适合的外植体是新切下的枝条插入含有蛭石和充足水的营养钵中24 h以上,使其在弱光下迅速长出嫩枝的茎切段和茎尖.茎切段和茎尖外植体经0.1%HgCl2或5%NaClO溶液表面消毒后,接种到大量元素减半、含0.5 mg/L 6-BA和0.03 mg/L NAA的MS培养基上诱导芽,试管苗的生根采用含0.5 mg/L IBA的MS培养基.试管苗茎段的分化依外源激素条件的不同而异. 相似文献
98.
This paper constructs a new non-uniform Doo-Sabin subdivision scheme via eigen polygon.The authors proved that the limit surface is always convergent and is G1 continuous for any valence and any positive knot intervals under a minor assumption, that λ is the second and third eigenvalues of the subdivision matrix. And then, a million of numerical experiments are tested with randomly selecting positive knot intervals, which verify that our new subdivision scheme satisfies the assumption.However this is not true for the other two existing non-uniform Doo-Sabin schemes in Sederberg, et al.(1998), Huang and Wang(2013). In additional, numerical experiments indicate that the quality of the new limit surface can be improved. 相似文献
99.
为解决通信辐射源识别中传统的人工特征提取方法鲁棒性不足和深度学习方法需要大量带标签目标域数据的问题,提出一种基于深度残差适配网络的通信辐射源个体识别方法.应用深度学习技术实现从源域到目标域上的迁移识别,只需要将带标签的源域数据和无标签的目标域数据进行训练.原始通信辐射源信号经过预处理后输入网络训练,将源域和目标域的分布... 相似文献
100.
Julie Patenaude Michele D’Elia Claudine Hamelin Jacques Bernier 《Cellular and molecular life sciences : CMLS》2010,67(8):1315-1329
Burn injury causes an immunosuppression associated with suppressed adaptive immune function. Dendritic cells (DCs) are APCs
for which signaling via their Toll-like receptors (TLRs) induces their maturation and activation, which is essential for the
adaptive immune response. In this study, we examined if burn injury alters the TLR activity of splenic DCs. After injury,
we noticed that DC functions were impaired, characterized by a suppressed capacity to prime naive T cells when triggering
the TLR4 signaling cascade using specific ligands (LPS or rHSP60). The observed perturbations on LPS-primed DCs isolated from
burned mice exhibited significantly diminished IL-12p40 production and enhanced IL-10 secretion-associated impairment in mitogen-activated
protein kinase activation. Interestingly, we observed a decrease of TLR4/MD-2 expression on the CD8α+ DC subset that persisted following LPS stimulation. The altered TLR4 expression on LPS-stimulated CD8α+ DCs was associated with reduced capacity to produce IL-12 after stimulation. Our results suggested that TLR4 reactivity on
DCs, especially CD8α+ DCs, is disturbed after burn injury. 相似文献