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981.
电动汽车造型设计分析 总被引:1,自引:0,他引:1
内燃式发动机汽车的污染问题已经迫在眉睫,而新能源汽车则能很好地解决这一问题.其中电动汽车能大大提高能量利用率,在原本的内燃式发动机汽车的机械传动被更改为电能传动时,不必要的传动损耗被减少.电动汽车的能源利用效率高达19%以上,而内燃式发动机汽车则低于12%.因此电动汽车较于内燃式发动机汽车拥有较多优势,大力发展电动汽车也是大势所趋.本文首先分析了电动汽车的发展背景,在此基础上提出电动汽车的造型趋势,对轻量化设计和模块化设计重点进行了分析.其次基于人机工程学对电动汽车造型的主要人机界面进行了分析. 相似文献
982.
Gang Cheng Teng Fei Yi Zhao Yanxiang Cheng Yuguang Ma Shiyong Liu 《Thin solid films》2008,516(15):5133-5136
Characteristics of white organic light-emitting devices based on phosphor sensitized fluorescence are improved by using a multiple-emissive-layer structure, in which a phosphorescent blue emissive layer is sandwiched between red and green&yellow ones. In this device, bis[(4,6–difluorophenyl)–pyridinato–N,C2] (picolinato), bis(2,4–diphenyl–quinoline) iridium (III) acetylanetonate, fac tris (2-phenylpyridine) iridium, and 5,6,11,12–tetraphenylnaphthacene are used as blue, red, green, and yellow emitters, respectively. The device has a maximum luminance of more than 30,000 cd/m2, a maximum luminous efficiency of 27 cd/A, a maximum external quantum efficiency of 12.4%, and a color rendering index of 81 at 100 cd/m2. 相似文献
983.
984.
Fei Zhen Wang Bo Ho Ching-Hwa Lin Fang Yuan Jun Zhang Ze Jin Chuanhong 《Nano Research》2017,10(7):2535-2544
In the current extensive studies of layered two-dimensional (2D) materials,compared to hexagonal structures such as graphene,hBN,and MoS2,lowsymmetry 2D materials have shown great potential for applications in anisotropic devices.Rhenium diselenide (ReSe2) possesses the bulk space group P(1) and belongs to the triclinic crystal system with a deformed cadmium-iodide-type structure.Here,we propose an electron diffraction-based method to distinguish the monolayer ReSe2 membrane from multilayer ReSe2 and its two different vertical orientations.Our method is also applicable to other low-symmetry crystal systems,including both triclinic and monoclinic lattices,as long as their third unit-cell basis vectors are not perpendicular to the basal plane.Our experimental results are well explained by kinematical electron diffraction theory and the corresponding simulations.Generalization of our method to other 2D materials,such as graphene,is also discussed. 相似文献
985.
目的在低温环境条件下,测试与分析2种冲击高度(61,76 cm)下聚乙烯发泡材料的动态缓冲性能。方法参考实际包装件流通环境的温度范围,分别在23,0,-15,-30℃等4种温度条件下进行聚乙烯发泡材料的动态冲击试验。结果在低温环境条件下的EPE动态冲击曲线中,对应于最小加速度处的静应力较常温条件下的增加0.9~2.5 k Pa,加速度值降低约7~8 g。结论低温环境下,缓冲材料动态载荷能力增加,其最小加速度值低于常温条件下相同受力状态下的数值。在实际包装设计中,应结合实际流通环境温度进行缓冲设计。 相似文献
986.
目的 针对目前陪伴类产品因功能延展性差而导致产品闲置和资源浪费这一现实问题,从双用户出发构建一套较为适用的功能识别方法模型,来深层次挖掘功能拓展潜力和提高功能延展性。方法 从主用户和陪伴用户来细分多用户构建协同用户角色模型,通过查阅文献资料、访谈调研等方法,来深层次挖掘用户的需求功能,运用KANO模型获取分功能要素在产品整体需求功能中的权重因子,综合运用随机和组合过程计算产品功能组合方案的总体需求度排序,由此筛选出用户需求度较高且与主用户具有匹配度的功能组合方案。结论 以婴儿车为例,运用该方法进行功能方案的输出,验证该方法模型操作的科学性和有效性。 相似文献
987.
All Inorganic Halide Perovskites Nanosystem: Synthesis,Structural Features,Optical Properties and Optoelectronic Applications 下载免费PDF全文
Xiaoming Li Fei Cao Dejian Yu Jun Chen Zhiguo Sun Yalong Shen Ying Zhu Lin Wang Yi Wei Ye Wu Haibo Zeng 《Small (Weinheim an der Bergstrasse, Germany)》2017,13(9)
The recent success of organometallic halide perovskites (OHPs) in photovoltaic devices has triggered lots of corresponding research and many perovskite analogues have been developed to look for devices with comparable performance but better stability. Upon the preparation of all inorganic halide perovskite nanocrystals (IHP NCs), research activities have soared due to their better stability, ultrahigh photoluminescence quantum yield (PL QY), and composition dependent luminescence covering the whole visible region with narrow line‐width. They are expected to be promising materials for next generation lighting and display, and many other applications. Within two years, a lot of interesting results have been observed. Here, the synthesis of IHPs is reviewed, and their progresses in optoelectronic devices and optical applications, such as light‐emitting diodes (LEDs), photodetectors (PDs), solar cells (SCs), and lasing, is presented. Information and recent understanding of their crystal structures and morphology modulations are addressed. Finally, a brief outlook is given, highlighting the presently main problems and their possible solutions and future development directions. 相似文献
988.
Fei Li Heqiu Zhang Lizhong Hu Yingmin Luo Yu Zhao Yu Qiu Jiuyu Ji Lunlun Yue 《Journal of Materials Science: Materials in Electronics》2013,24(12):4812-4816
One-dimensional (1D) ZnO microwires were successfully synthesized by chemical vapor deposition and their structural and morphological properties were analyzed by X-ray diffraction and scanning electron microscopy, demonstrating that the microwires were single crystalline with perfect hexagonal structure and smooth surface. Using these 1D microstructures, we fabricated a novel ZnO-based ethanol gas sensor. Operating at room temperature, the sensor was found to have good sensing characteristics. The reliability and stability of the sensor could be improved by connecting multiple 1-wire devices (1-WD) in parallel into a multi-wires device. In interior natural lighting environment and under 3 V bias, the response and recovery time of the 1-WD to 200 ppm ethanol gas were <10 s and about 300 s, respectively, and the minimum and maximum detection limit were about 2 and 200 ppm, respectively. A sensing model was proposed for discussing the performance of the sensor. The simplicity in fabrication, low power consumption and low cost make the sensor suitable for practical application in many fields, especially in identifying driving under the influence and chemical industry monitoring. 相似文献
989.
990.