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71.
Low voltage organic field effect memory transistors are demonstrated by adapting a hybrid gate dielectric and a solution processed graphene oxide charge trap layer. The hybrid gate dielectric is composed of aluminum oxide (AlOx) and [8-(11-phenoxy-undecyloxy)-octyl]phosphonic acid (PhO-19-PA) plays an important role of both preventing leakage current from gate electrode and providing an appropriate surface energy to allow for uniform spin-casting of graphene oxide (GO). The hybrid gate dielectric has a breakdown voltage greater than 6 V and capacitance of 0.47 μF/cm2. Graphene oxide charge trap layer is spin-cast on top of the hybrid dielectric and has a resulting thickness of approximately 9 nm. The final device structure is Au/Pentacene/PMMA/GO/PhO-19-PA/AlOx/Al. The memory transistors clearly showed a large hysteresis with a memory window of around 2 V under an applied gate bias from 4 V to −5 V. The stored charge within the graphene oxide charge trap layer was measured to be 2.9 × 1012 cm−2. The low voltage memory transistor operated well under constant applied gate voltage and time with varying programming times (pulse duration) and voltage pulses (pulse amplitude). In addition, the drain current (Ids) after programming and erasing remained in their pristine state after 104 s and are expected to be retained for more than one year.  相似文献   
72.
For the fine‐pitch application of flip‐chip bonding with semiconductor packaging, fluxing and hybrid underfills were developed. A micro‐encapsulated catalyst was adopted to control the chemical reaction at room and processing temperatures. From the experiments with a differential scanning calorimetry and viscometer, the chemical reaction and viscosity changes were quantitatively characterized, and the optimum type and amount of micro‐encapsulated catalyst were determined to obtain the best pot life from a commercial viewpoint. It is expected that fluxing and hybrid underfills will be applied to fine‐pitch flip‐chip bonding processes and be highly reliable.  相似文献   
73.
Uncrewed aerial vehicles (UAVs) have become a vital element in nonterrestrial networks, especially with respect to 5G communication systems and beyond. The use of UAVs in support of 4G/5G base station (uncrewed aerial vehicle base station [UAV-BS]) has proven to be a practical solution for extending cellular network services to areas where conventional infrastructures are unavailable. In this study, we introduce a UAV-BS system that utilizes a high-capacity wireless backhaul operating in millimeter-wave frequency bands. This system can achieve a maximum throughput of 1.3 Gbps while delivering data at a rate of 300 Mbps, even at distances of 10 km. We also present the details of our testbed implementation alongside the performance results obtained from field tests.  相似文献   
74.
A novel fabrication method of the core mode blocker by exposing H/sub 2/-loaded Ge-B codoped fibres to local electric arc discharge for application to the LPFGs-based tunable all-fibre bandpass filter with 6.5 nm bandwidth and 40 nm tuning range is presented.  相似文献   
75.
A novel, maskless, low‐volume bumping material, called solder bump maker, which is composed of a resin and low‐melting‐point solder powder, has been developed. The resin features no distinct chemical reactions preventing the rheological coalescence of the solder, a deoxidation of the oxide layer on the solder powder for wetting on the pad at the solder melting point, and no major weight loss caused by out‐gassing. With these characteristics, the solder was successfully wetted onto a metal pad and formed a uniform solder bump array with pitches of 120 µm and 150 µm.  相似文献   
76.
通过采用锁相放大器,演示了一种性能明显提高的锁模光纤激光陀螺.结果表明锁相放大器的输出与转动速率之间具有理想的线性关系,并对两脉冲(在时间间隔测量过程中引起相位误差)之间的光强差不敏感.与以往报道的时间间隔测量相比,演示了长期稳定性提高了二个数量级.  相似文献   
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This study was conducted to determine the resistance of acid-shocked Cronobacter sakazakii to environmental stresses. C. sakazakii pre-exposed to various pH levels was treated with acid stress (pH 3.06), heat stress (55°C), and organic acid stress, respectively. Overall, higher D-values were obtained in samples pre-exposed to acidic pH conditions (pH 3.06, 4.00, and 5.02) compared to a control (pH 7.20) when the samples were subsequently stressed. For 0.1 M acetic acid, the D-values of nonadapted C. sakazakii ATCC 29004 and ATCC 29544 were 19.69 and 15.49 h, respectively, whereas the D-values of acid-shocked C. sakazakii ATCC 29004 and ATCC 29544 by pre-exposure to pH 4.0 were 34.59 and 24.25 h, respectively. Acid adaptation of C. sakazakii by preexposure to acidic pH can enhance the resistance of cells against subsequent environmental stresses such as acidic pH, heat, and organic acids.  相似文献   
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