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101.
Vegetable oils are now considered to be a potential alternative that can be used in place of partial or total substitution of diesel fuels. In this study, we used diethyl ether as an oxygenated additive to investigate the possible use of higher percentages of biodiesel in an unmodified diesel engine. Neem oil was selected for biodiesel production. The tests were performed at a steady-state condition in a single-cylinder constant speed DI diesel engine. The combustion process involved in diesel engine would be improved and the particulate matter would be reduced if these biodiesels are blended. An experimental investigation is carried out to establish the emission characteristics of a direct injection diesel engine using diethyl ether as additive in Neat Neem oil Biodiesel. Emissions of hydro carbon oxides of nitrogen and carbon monoxide significantly reduced by adding diethyl ether into neem oil biodiesel at 10% and 20% on volume basis.  相似文献   
102.
Real‐time tracking of the dynamics change of self‐assembled nanostructures in physiological environments is crucial to improving their delivery efficiency and therapeutic effects. However, such tracking is impeded by the complex biological microenvironment leading to inhomogeneous distribution. A rotatable fluorescent ratio strategy is introduced that integrates aggregation‐induced emission (AIE) and aggregation‐caused quenching (ACQ) into one nanostructured system, termed AIE and ACQ fluorescence ratio (AAR). Following this strategy, an advanced probe, PEG5k‐TPE4‐ICGD4 (PTI), is developed to track the dynamics change. The extremely sharp fluorescent changes (up to 4008‐fold) in AAR allowed for the clear distinguishing and localization of the intact state and diverse dissociated states. The spatiotemporal distribution and structural dynamics of the PTI micelles can be tracked, quantitatively analyzed in living cells and animal tissue by the real‐time ratio map, and be used to monitor other responsive nanoplatforms. With this method, the dynamics of nanoparticle in different organelles are able to be investigated and validated by transmission electron microscopy. This novel strategy is generally applicable to many self‐assembled nanostructures for understanding delivery mechanism in living systems, ultimately to enhance their performance in biomedical applications.  相似文献   
103.
The emission characteristics of a petrol–ethanol–diethyl-ether blend as a carbon monoxide reduction additive in a spark ignition (SI) engine is presented. The experimental set-up is consisting of a Villiers G200, 6.5?hp, 4-stroke; single cylinder SI engine. The blend used was synthesised using petrol, ethanol and diethyl ether in the following percentage proportion by volume as 75:15:10, 60:25:15, 80:15:5, 85:10:5, respectively. These blends were tested at full engine load and at an operational speed of 2500?rpm. Exhaust emission probe was inserted at the exhaust pipe in order to determine the emission characteristics of these blends under different operating conditions. The results obtained during the emission test carried out show that CO emission level of petrol is higher than that of any of the blends with the 60:25:15 blends having the least emission level. The lowest CO emission of the blend is due to the high oxygen content of fuel blend. The above result shows a great promise in the fight against carbon oxide emission.  相似文献   
104.
本研究分析了钢铁企业焦化和烧结两个重点工序中烟气污染物排放现状和钢铁行业当前的环保政策。对焦化及烧结烟气污染物的排放特征进行了分析,并通过对比燃煤电厂烟气特点,提出可以综合电厂烟气治理模式和自身特点改进的技术路线。结合某大型国有钢铁企业的脱硫脱硝装备对其环保现状进行了分析。针对焦化和烧结工序的典型污染物硫、硝、尘现有的源头减排、过程控制及末端处理技术,分析其优缺点。进而提出了3条可实现烟气污染物超低排放的技术路线,即半干法脱硫耦合选择性催化还原脱硝、半干法/湿法耦合臭氧氧化脱硝、活性焦脱硫脱硝一体化技术,重点介绍了这些技术在某大型钢铁企业的应用实践及应用效果。并基于全过程耦合技术,分别在焦化和烧结工序中提出了多污染物协同去除技术及应用,即焦炉低氮燃烧技术耦合末端活性焦多污染物协同控制技术、烧结烟气循环技术耦合末端活性焦多污染物协同控制技术。最后结合几种技术路线的应用实践,对未来钢铁产业的烧结及焦化工序超低排放技术的选择提出合理化建议。  相似文献   
105.
Circulating fluidized bed (CFB) boilers has realized the clean and efficient utilization of inferior coal like gangue and coal slime, high sulfur coal, anthracite, petroleum coke, oil shale and other resources. As a country with the largest amount of CFB boilers and the largest installed capacity in the world, China has 440 100–600 MWe CFB boilers with a total capacity of 82.29 GWe, including 227 units of 135 MWe, 95 units of 300 MWe, and 24 supercritical units. The statistics of typical 100–300 MWe CFB boilers showed that the average number of unplanned shut-down was only 0.37 times per year, among which the 135 MWe was 0.26 times per year and 300 MWe was 0.46 times per year. The auxiliary power ratio of some 300 MWe CFB boilers based on flow-pattern reconstruction can be reduced to about 4%, which is closed to the same level of pulverized coal (PC) boilers. This paper summarizes the development process and application status of China’s large-scale CFB boilers, analyzes the characteristics and technical performance of the iconic units, and introduces solutions to the problems such as water wall wear and bottom ash cooling.  相似文献   
106.
为研究商用车实际道路排放试验的影响因素,基于便携式排放测量系统(portable emission measurement system,PEMS)测试技术,进行多组车载排放试验。通过试验数据定性分析试验工况、整车速比、整车载荷、试验海拔等对整车PEMS测试结果的影响。研究表明,整车变速箱、后桥配置存在最佳速比匹配区间,稳定的驾驶工况有利于整车排放,高海拔地区排放变差,且高负荷工况恶化严重,整车载荷、空气湿度与排放结果呈负相关。并从排放检测试验过程、整车配置、整车ECU数据等方面对试验数据进行分析,确定试验条件变化影响整车后处理转化效率和发动机燃烧性能,导致发动机排放性能变化。  相似文献   
107.
Upconversion Sr2(Gd.98-xEr.02Ybx)8Si6O26 (SGSO:2Er3+/xYb3+) phosphor materials were synthesized using a citrate sol-gel process. X-ray diffraction patterns confirmed their hexagonal structure. Field emission scanning electron microscopy images of SGSO:2Er3+/xYb3+ phosphors depicted submicron particles. The enhanced upconversion luminescence properties of SGSO:2Er3+/xYb3+ phosphors were analysed as a function of Yb3+ ion concentration and laser power. The energy transfer induced enhanced emission of the Er3+/ Yb3+ ions co-doped SGSO phosphors was ascribed to multi-phonon relaxation. The calculated chromaticity coordinates of the SGSO:2Er3+/xYb3+ phosphors showed emissions could be tuned by changing Yb3+ ion concentration. Optimized sample exhibited the chromaticity coordinate values near to the ultra-high definition television standard green emission coordinates.  相似文献   
108.
秦斌  冯齐 《新疆钢铁》2020,(1):9-11
介绍了八钢烧结在原料二氧化硫含量不断上升、烧结脱硫系统承载超负荷运行情况下,通过优化配矿结构、完善脱硫系统工艺和烧结脱硫操作等措施,提高了脱硫能力。经过一年多的运行实践,脱硫设施和烧结运转率达到98%以上,脱硫效率达到98%,粉尘排放浓度控制在10mg/m^3。  相似文献   
109.
Over the last decade, narrow-band emitters have been recognized as key enablers for light emitting diodes (LEDs) backlights in liquid-crystal displays (LCDs) by competing with other display technologies. Today, efforts have been devoted to the exploration of narrow-band green/red luminescent materials with high quantum efficiency and excellent stability to optimize the performance of LED backlights. This review first presents an overview of the significant progress made in the development of narrow-band emitters used in LED backlights for LCDs with the emphasis on the versatile materials databases from doped phosphors to luminescent II–VI, III-V semiconductor quantum dots, and the recent halide perovskites nanocrystals and bulk metal halides. Subsequently, the correlation of structure-luminescence properties, and the device performance optimization of these emitters have been analyzed. The focus is placed on summarizing and comparing the remarkable examples of outdated and new narrow-band luminescent materials as potential candidates in LED backlights. Finally, the outlooks and challenges in discovering new narrow-band emitters have been proposed.  相似文献   
110.
为了准确测量不同材料在实际环境中的二次电子空间分布,设计了一种新型的二次电子发射空间分布测量结构,给出了实验测量原理,用求解特征矩阵的方法对实验结果进行处理,得到了所需的二次电子空间分布。通过模拟计算对该测量方法进行了校验,模拟结果与假设二次电子空间分布函数相吻合,表明该测量方法可靠、测量精度高,为后续样机研制奠定了理论基础。  相似文献   
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