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1.
随着区域城市人口增加和人民生活水平提高,江淮丘陵区中小河流水环境污染问题日益突出,成为区域社会经济发展的主要制约因素之一。本文以位于江淮丘陵区马槽河流域为研究对象,通过资料收集、问卷调查、实地勘察等手段,查明该地区入河污染物指标 COD、氨氮、TN、TP 主要贡献因素及占比,其中生活污染(51%,40%,54%,28%)、面源污染(6%,38%,9%,42%)、畜禽养殖(39%,15%,17%,25%)三类型贡献占比 90%以上,内源污染和水产养殖较少。针对污染源调查结果特征,提出镇区管网完善、农村分散处理、畜禽粪污处理、养殖废水农田消纳、污染缓冲带设置、径流拦截与再利用、河流生态化改造等治理建议,可为今后中小河流污染源调查与治理提供借鉴。 相似文献
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对保证某型雷达数字阵列模块(DAM)有效散热的风机组件批量报故问题进行系统分析,兼顾产品外购及其自身特点,并从保证可靠性、控制成本支出的角度,统筹改进方案。完成产品设计、工艺、维护的研究,完成相关改进及实物验证。最终把改进的技术成功用于产品上,以提高产品环境适应性,提升装备可靠性。 相似文献
4.
以2,4-二硝基氯苯、甲醇钠甲醇溶液为原料,在不同反应批次中,按相应配比在甲醇溶液中回流制备2,4-二硝基苯甲醚,通过滤除生成的氯化钠、套用母液的处理方式,提高原子利用率,改善工艺环境友好性。在实验条件下,母液套用9次,2,4-二硝基氯苯利用率99.0%,2,4-二硝基苯甲醚折纯收率97.4%。 相似文献
5.
为快速、准确检测烟草中高级脂肪酸含量,建立了测定烟草中7种高级脂肪酸的液相色谱-串联质谱(LC-MS/MS)方法。样品经KOH的甲醇溶液皂化,二氯甲烷萃取后,十七烷酸作内标直接进样LC-MS/MS分析定量。结果表明各高级脂肪酸峰面积与内标峰面积的比值和其浓度与内标浓度之比的线性关系良好(R2 ≥ 0.9818),加标回收率在87.5% ~ 109%之间,平均相对标准偏差(RSD)在1.1%~4.7%之间,方法的检出限(LOD)和定量限(LOQ)分别为0.0004~ 0.007 mg/g和0.001~0.02 mg/g。该方法适用于烟草7种高级脂肪酸的快速测定,具有简单、快速、灵敏等特点。 相似文献
6.
Handling appearance variations is a challenging issue in visual tracking. Existing appearance models are usually built upon a linear combination of templates. With such kind of representation, accurate visual tracking is not desirable when heavy appearance variations are in presence. Under the framework of particle filtering, we propose a novel target representation for tracking. Namely, the target candidates are represented by affine combinations of a template set, which leads to better capability in describing unseen target appearances. Additionally, in order to adapt this representation to dynamic contexts across a video sequence, a novel template update scheme is presented. Different from conventional approaches, the scheme considers both the importance of one template to a target candidate in the current frame and the recentness of the template that is kept in the template set. Comprehensive experiments show that the proposed algorithm achieves superior performances in comparison with state-of-the-art works. 相似文献
7.
In recent years, porous silicon (PSi) has attracted a great deal of attention for sensing applications. However, the high reactivity of PSi surfaces causes serious problems of stability. In this work, we developed new thin films that can serve as stabilizer of PSi for CO2 gas sensors development. PSi surface was coated with carbon nitride (CNx) film which is one of the most important interfering to stabilize the PSi layer. CNx film was deposited by pulsed laser ablation. The effect of CO2 gas on the sensor response was investigated for different polarization voltages. The electrical properties of (Al/CNx/PSi/Si) structure were modified in the presence of the gas. The device shows a high sensitivity against CO2 gas. Furthermore, the current variation of the sensor as a function of time has been investigated. The results show that the Al/CNx/PSi/Si structure becomes stable after the first two weeks. 相似文献
8.
Wei Mengnan Ban Boyuan Li Jingwei Sun Jifei Li Feifei Jiang Xuesong Chen Jian 《SILICON》2020,12(2):327-338
Silicon - A novel green cationic surfactant Poly (propylene glycol) bis (2-aminopropyl ether) (PEA) with multiple amine groups was utilized as a collector for flotation separation of quartz from... 相似文献
9.
本文提出一种高性能通用DSP扩展寄存器的设计及实现方法,该方法是我国自主研发的高性能通用DSP中实现寄存器堆扩展的一种新方法,其优点是在不影响现有指令集及指令机器码位宽的前提下,实现对处理器内部寄存器堆的成比例扩展。通过在我国自主研制DSP上的实际应用,证明了该扩展方法的有效性和实用性。 相似文献
10.
《International Journal of Hydrogen Energy》2020,45(19):10979-10990
The pyrolysis processes of oleaginous yeast and algae were studied and compared using a non-isothermal thermogravimetric analyzer at heating rates of 10–50 °C/min, and the most probable mechanism function and kinetic analyses of the main stage of pyrolysis were carried out by the Popuse method, Starink method, and Fridemen method. The main pyrolysis stage of the samples could be described by the Jander equation and Z–L–T equation and the activation energy of the three biomass was 108–117, 107–121 and 93–108 kJ/mol, respectively. For the three kinds of biomass, the DTG curves were divided based on the four pseudo-components by performing Gaussian fitting which are carbohydrates, proteins, lipids, others, and the weight coefficients of them could be identified. The activation energy of each pseudo-component was obtained in the range of 58.36–140.44 kJ/mol by the Kissinger method. The four-pseudo-component model based on Gaussian fitting provides effective data for the design of oleaginous yeast and algae thermal decomposition systems and the kinetic analysis of the pyrolysis process. 相似文献