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111.
用纳米铜油墨印刷RFID标签天线   总被引:1,自引:0,他引:1  
采用廉价的纳米铜导电油墨直接印刷电路图案,再经紫外固化形成导电线路,铜膜导电线路表现出金属般的外观,其电阻率是纯铜的10倍,成本接近当前印刷线路板的成本,且工艺简单、环保和生产灵活,可望在一些领域替代传统的蚀刻电子线路.  相似文献   
112.
Light emission of 2‐(2,6‐bis((E)‐4‐(diphenylamino)styryl)‐4H‐pyran‐4‐ylidene)malononitrile (TPA‐DCM) is weakened by aggregate formation. Attaching tetraphenylethene (TPE) units as terminals to TPA‐DCM dramatically changes its emission behavior: the resulting fluorogen, 2‐(2,6‐bis((E)‐4‐(phenyl(4′‐(1,2,2‐triphenylvinyl)‐[1,1′‐biphenyl]‐4‐yl)amino)styryl)‐4H‐pyran‐4‐ylidene)malononitrile (TPE‐TPA‐DCM), is more emissive in the aggregate state, showing the novel phenomenon of aggregation‐induced emission (AIE). Formulation of TPE‐TPA‐DCM using bovine serum albumin (BSA) as the polymer matrix yields uniformly sized protein nanoparticles (NPs) with high brightness and low cytotoxicity. Applications of the fluorogen‐loaded BSA NPs for in vitro and in vivo far‐red/near‐infrared (FR/NIR) bioimaging are successfully demonstrated using MCF‐7 breast‐cancer cells and a murine hepatoma‐22 (H22)‐tumor‐bearing mouse model, respectively. The AIE‐active fluorogen‐loaded BSA NPs show an excellent cancer cell uptake and a prominent tumor‐targeting ability in vivo due to the enhanced permeability and retention effect.  相似文献   
113.
This paper reports the first integration of laser‐etched polycrystalline diamond microchannels with template‐fabricated microporous copper for extreme convective boiling in a composite heat sink for power electronics and energy conversion. Diamond offers the highest thermal conductivity near room temperature, and enables aggressive heat spreading along triangular channel walls with 1:1 aspect ratio. Conformally coated porous copper with thickness 25 µm and 5 µm pore size optimizes fluid and heat transport for convective boiling within the diamond channels. Data reported here include 1280 W cm?2 of heat removal from 0.7 cm2 surface area with temperature rise beyond fluid saturation less than 21 K, corresponding to 6.3 × 105 W m?2 K?1. This heat sink has the potential to dissipate much larger localized heat loads with small temperature nonuniformity (5 kW cm?2 over 200 µm × 200 µm with <3 K temperature difference). A microfluidic manifold assures uniform distribution of liquid over the heat sink surface with negligible pumping power requirements (e.g., <1.4 × 10?4 of the thermal power dissipated). This breakthrough integration of functional materials and the resulting experimental data set a very high bar for microfluidic heat removal.  相似文献   
114.
为解决某火炮制退杆沟槽加工工艺性差、加工精度低的难题,对原有加工工艺和用于加工沟槽的紫铜电极进行分析,提出了一种新的电极结构,并采用ABAQUS有限元法和Matlab微分法对新结构进行静力分析。仿真结果表明:该方法可将制退流液孔面积加工误差由3.405 mm2减小至0.5 mm2以内,适用于制退杆沟槽的精细加工。  相似文献   
115.
Integration of 2D membranes into 3D macroscopic structures is essential to overcome the intrinsically low stretchability of graphene for the applications in flexible and wearable electronics. Herein, the synthesis of 3D graphene films (3D‐GFs) using chemical vapor deposition (CVD) is reported, in which a porous copper foil (PCF) is chosen as a template in the atmospheric‐pressure CVD preparation. When the 3D‐GF prepared at 1000 °C (noted as 3D‐GF‐1000) is transferred onto a polydimethylsiloxane (PDMS) membrane, the obtained 3D‐GF‐1000/PDMS hybrid film shows an electrical conductivity of 11.6 S cm?1 with good flexibility, indicated by small relative resistance changes (ΔR/R0) of 2.67 and 0.36 under a tensile strain of 50% and a bending radius of 1.6 mm, respectively. When the CVD temperature is reduced to 900 °C (generating a sample noted as 3D‐GF‐900), the 3D‐GF‐900/PDMS hybrid film exhibits an excellent strain‐sensing performance with a workable strain range of up to 187% and simultaneously a gauge factor of up to ≈1500. The 3D‐GF‐900/PDMS also shows a remarkable durability in resistance in repeated 5000 stretching‐releasing cycles. Kinetics studies show that the response of ΔR/R0 upon strain is related to the graphitization and conductivity of 3D‐GF which are sensitive to the CVD preparation temperature.  相似文献   
116.
Soluble molecular red emitters 1a / 1b are synthesized by Stille coupling from 2‐(3,5‐di(1‐naphthyl)phenyl)thiophene precursors. The compounds show emission maxima at ca. 610 nm in CH2Cl2 solution and 620 nm in solid films. Replacing the n‐hexyl substituent by 4‐sec‐butoxyphenyl produces a marked increase of glass transition temperature (Tg) from 82 °C to 137 °C and increases the solubility in toluene and p‐xylene, thus improving the film‐forming properties. Cyclic voltammetry shows that the compounds can be reversibly oxidized and reduced around +1.10 and ?1.20 V, respectively. A two‐layered electroluminescent device based on 1b produces a pure red light emission with CIE coordinates (0.646, 0.350) and a maximal luminous efficiency of 2.1 cd A?1. Furthermore, when used as a solution‐processed red emitter in optically pumped laser devices, compound 1b successfully produces a lasing emission at ca. 650 nm.  相似文献   
117.
无卤无磷覆铜板将成为覆铜板绿色化的新阶段,文章介绍了斗山电子的无卤无磷覆铜板DS-7409HG系列型号的特点。  相似文献   
118.
PCB基板材料用新型环氧树脂发展综述   总被引:1,自引:0,他引:1  
文章对日本近年在高性能PCB基板材料用新型环氧树脂的品种、性能及应用进行了阐述。  相似文献   
119.
We use three-dimensional (3D) grain-continuum models to study grain boundary migration, treating each grain with anisotropic elastic properties. Grain boundary speeds are computed using a finite element method to calculate differences in strain energy density across grain boundaries. Body-fitted finite element meshes are used. An interface tracking program, PLENTE, is used to develop starting structures and move the grain boundaries based on these speeds. We demonstrate this procedure on textured films consisting of 〈100〉 and 〈111〉 fiber textured film. We also apply the model to a short section of a Cu line embedded in oxide. We conclude with a discussion on the relative impact of different driving forces for grain boundary motion.  相似文献   
120.
半导体封装行业中铜线键合工艺的应用   总被引:1,自引:0,他引:1  
毕向东 《电子与封装》2010,10(8):1-4,13
文章介绍了半导体封装行业中铜线键合工艺下,各材料及工艺参数(如框架、劈刀、设备参数、芯片铝层与铜材的匹配选择)对键合质量的影响,并总结提出如何更好地使用铜线这一新材料的规范要求。应用表明芯片铝层厚度应选择在0.025mm以上;劈刀应使用表面较粗糙的;铜线在键合工艺中使用体积比为95:5的氢、氮气混合保护气体;引线框架镀银层厚度应控制在0.03mm~0.06mm。  相似文献   
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