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991.
992.
993.
Dynamic response and microstructure evolution of the finite steel target subjected to high velocity impact by copper explosively formed projectile
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J.F. Liu Y. Long C. Ji M.S. Zhong 《Fatigue & Fracture of Engineering Materials & Structures》2017,40(12):2141-2151
The dynamic deformation of the finite steel target subjected to high velocity impact of copper explosively formed projectile is investigated by optical, scanning, and transmission electron microscopy. Morphology analysis of fracture surfaces indicates that the copper remainder plated to the crater wall shows extremely plastic deformation, which consists of elongated parabolic dimples, and the mild carbon steel target exhibits excellent brittle features that material fails mainly along the cleavage facets on the rear surface of target under strong impact of explosively formed projectile. In the surface of crater, the whole part of copper remainder and partial material of steel target undergoes completely dynamic recrystallization. The layer thickness of dynamic recrystallization zone, which displays an extreme plastic flow in solid state, is about 21.3 μm in steel target, and the average size of the refined grains significantly decreases to approximately 200 nm. Theoretically calculated results indicate that the temperature increase is associated with shock wave and plastic deformation of steel target and can reach 1352 K, which is 0.75Tm (where Tm is the melting temperature of steel target). The change in microhardness from the crater wall to the matrix of target is consistent with micro‐deformation of grains, and maximum microhardness is observed on the interface between dynamic recrystallization and severe plastic deformation zones of steel target. 相似文献
994.
Yanpeng Liu Eun Jung Yu Wang Yi Zheng Eun Ji Park Sung Min Cho Kian Ping Loh 《Small (Weinheim an der Bergstrasse, Germany)》2014,10(5):944-949
An air‐stable transparent conductive film with “quasi‐freestanding” graphene supported on horizontal single walled carbon nanotubes (SWCNTs) arrays is fabricated. The sheet resistance of graphene films stacked via layer‐by‐layer transfer (LBL) on quartz, and modified by 1‐Pyrenebutyric acid N‐hydroxysuccinimide ester (PBASE), is reduced from 273 Ω/sq to about 76 Ω/sq. The electrical properties are stable to heat treatment (up to 200 ºC) and ambient exposure. Organic light‐emitting diodes (OLEDs) constructed of this carbon anode (T ≈ 89.13% at 550 nm) exhibit ≈88% power efficiency of OLEDs fabricated on an ITO anode (low turn on voltage ≈3.1 eV, high luminance up to ≈29 490 cd/m2, current efficiency ≈14.7 cd/A). Most importantly, the entire graphene‐on‐SWCNT hybrid electrodes can be transferred onto plastic (PET) forming a highly‐flexible OLED device, which continues to function without degradation in performance at bending angles >60°. 相似文献
995.
目的 探析在地实践语境下,红色文化转化为文创产品的设计路径,以此寻求上海红色文创产品设计的新思路,助力红色文化的传承与发扬。方法 通过对上海红色文创产品设计的现状分析确立地域特色的重要性。基于情感化设计理念,将上海红色文化资源分层整理,并深入研究在地性背景下消费主体各层级的情感需求及文化转译的方法。最终构建出基于情感化设计理念的红色文创产品在地性实践模型,并通过设计团队的实践案例进行展示。结论 从情感满足的角度出发,提出在本能层级上以红色文化符号的地域识别性为提取原则并确保文化转译过程中的准确性;行为层级上在以海派崇实性为基准设定产品功能的同时强调产品的文化体验;反思层级上侧重通过产品理念、寓意、品质等要素的设计构建红色精神与上海价值的双重认同并将其长效延续的思路,力求为上海红色文创产品的地方性特色呈现提供积极的现实意义和参考价值。 相似文献
996.
Jumi Yun Dae Hoon Lee Ji Sun Im Hyung-Il Kim 《Materials science & engineering. C, Materials for biological applications》2012,32(6):1564-1570
Transdermal drug delivery system (TDDS) was prepared with temperature-responsive hydrogel. The graphite was oxidized and incorporated into hydrogel matrix to improve the thermal response of hydrogel. The micro heater was fabricated to control the temperature precisely by adopting a joule heating method. The drug in hydrogel was delivered through a hairless mouse skin by controlling temperature. The efficiency of drug delivery was improved obviously by incorporation of graphite oxide due to the excellent thermal conductivity and the increased interfacial affinity between graphite oxide and hydrogel matrix. The fabricated micro heater was effective in controlling the temperature over lower critical solution temperature of hydrogel precisely with a small voltage less than 1 V. The cell viability test on graphite oxide composite hydrogel showed enough safety for using as a transdermal drug delivery patch. The performance of TDDS could be improved noticeably based on temperature-responsive hydrogel, thermally conductive graphite oxide, and efficient micro heater. 相似文献
997.
998.
The paper concerns the removal of ammonium ions from aqueous solution using a modified clinoptilolite-Ca(2+)-formed clinoptilolite (CaY) prepared from natural clinoptilolite. The batch study results show that the pH has an effect on ammonium adsorption capacity as it can influence both the character of the exchanging ions and the clinoptilolite itself; the CaY has a high selectivity to NH(4)(+) and the exchange decreases with increasing temperature; ammonium ion uptake onto CaY was suitably described by the Langmuir model. The column results indicated that the effluent of simulated wastewater treated with CaY could meet the integrated wastewater discharge standard of China, and CaY can be circulated through regenerating by Ca(OH)(2). 相似文献
999.
1000.
介绍了一种基于光敏特性陶瓷浆料的浆料直写无模三维成型技术制备的线条直径为270μm的TiO2木堆结构光降解器件.对光敏浆料的配制方法、浆料直写无模成型的工艺原理进行了研究;利用TEM和XRD表征光敏浆料中TiO2粉体的形貌和物相;对器件的光降解性能进行了分析与测试;利用光学显微镜和SEM对成型后的样品结构、尺寸及表面微观形貌进行了分析,并基于此分析给出了这种器件高催化效率的原因.实验结果显示,该器件具有完整的三维木堆结构,表面粗糙多孔,极大地增加了光催化的作用面积,从而使其具有较高的光降解效率.在紫外光照射10min后,初始浓度为4mg/L的亚甲基蓝溶液降解率达到76%,紫外光照射20min后,亚甲基蓝溶液降解率可达91%. 相似文献