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991.
Multilayer Graphene: Chemical Vapor Deposition of Bernal‐Stacked Graphene on a Cu Surface by Breaking the Carbon Solubility Symmetry in Cu Foils (Adv. Mater. 32/2017) 下载免费PDF全文
992.
Alexander Vadimovich Polyakov Irina Petrovna Semenova Elena Vladimirovna Bobruk Seung Mi Baek Hyoung Seop Kim Ruslan Zufarovich Valiev 《Advanced Engineering Materials》2018,20(5)
993.
Se‐Woong Baek Jungmin Cho Joo‐Seong Kim Changjo Kim Kwangmin Na Sang‐Hoon Lee Sunhong Jun Jung Hoon Song Sohee Jeong Jang Wook Choi Jung‐Yong Lee 《Advanced materials (Deerfield Beach, Fla.)》2018,30(25)
A novel self‐charging platform is proposed using colloidal‐quantum‐dot (CQD) photovoltaics (PVs) via the near‐infrared (NIR) band for low‐power electronics. Low‐bandgap CQDs can convert invisible NIR light sources to electrical energy more efficiently than wider spectra because of reduced thermalization loss. This energy‐conversion strategy via NIR photons ensures an enhanced photostability of the CQD devices. Furthermore, the NIR wireless charging system can be concealed using various colored and NIR‐transparent fabric or films, providing aesthetic freedom. Finally, an NIR‐driven wireless charging system is demonstrated for a wearable healthcare bracelet by integrating a CQD PVs receiver with a flexible lithium‐ion battery and entirely embedding them into a flexible strap, enabling permanent self‐charging without detachment. 相似文献
994.
Jeongkyun Roh Jae Hyeon Ryu Geun Woo Baek Heeyoung Jung Seung Gi Seo Kunsik An Byeong Guk Jeong Doh C. Lee Byung Hee Hong Wan Ki Bae Jong‐Ho Lee Changhee Lee Sung Hun Jin 《Small (Weinheim an der Bergstrasse, Germany)》2019,15(7)
In recent past, for next‐generation device opportunities such as sub‐10 nm channel field‐effect transistors (FETs), tunneling FETs, and high‐end display backplanes, tremendous research on multilayered molybdenum disulfide (MoS2) among transition metal dichalcogenides has been actively performed. However, nonavailability on a matured threshold voltage control scheme, like a substitutional doping in Si technology, has been plagued for the prosperity of 2D materials in electronics. Herein, an adjustment scheme for threshold voltage of MoS2 FETs by using self‐assembled monolayer treatment via octadecyltrichlorosilane is proposed and demonstrated to show MoS2 FETs in an enhancement mode with preservation of electrical parameters such as field‐effect mobility, subthreshold swing, and current on–off ratio. Furthermore, the mechanisms for threshold voltage adjustment are systematically studied by using atomic force microscopy, Raman, temperature‐dependent electrical characterization, etc. For validation of effects of threshold voltage engineering on MoS2 FETs, full swing inverters, comprising enhancement mode drivers and depletion mode loads are perfectly demonstrated with a maximum gain of 18.2 and a noise margin of ≈45% of 1/2 VDD. More impressively, quantum dot light‐emitting diodes, driven by enhancement mode MoS2 FETs, stably demonstrate 120 cd m?2 at the gate‐to‐source voltage of 5 V, exhibiting promising opportunities for future display application. 相似文献
995.
996.
Five single-point aquaporin-2 (AQP2) mutations that cause non-X-linked nephrogenic diabetes insipidus (NDI) were characterized to establish the cellular defect and to develop therapeutic strategies. In Xenopus oocytes expressing AQP2 cRNAs, single-channel water permeabilities of mutants L22V, T126M, and A147T were similar to that of wild-type AQP2, whereas R187C and C181W were nonfunctional. In [35S]methionine pulse-chase experiments in transiently transfected CHO cells, half-times for AQP2 degradation were approximately 4 h for wild-type AQP2 and L22V, and mildly decreased for T126M (2.7 h), C181W (2.4 h), R187C (2.0 h), and A147T (1.8 h). Immunofluorescence showed three distinct AQP2-staining patterns: plasma membrane and endosomal staining (wild-type, L22V), endoplasmic reticulum (ER) staining (T126M > A147T approximately R187C), or a mixed pattern of reticular and perinuclear vesicular staining. Immunoblot of fractionated vesicles confirmed primary ER localization of T126M, R187C, and A147T. To determine if the AQP2-trafficking defect is correctable, cells were incubated with the "chemical chaperone" glycerol for 48 h. Immunoblot showed that glycerol produced a nearly complete redistribution of AQP2 (T126M, A147T, and R187C) from ER to membrane/endosome fractions. Immunofluorescence confirmed the cellular redistribution. Redistribution of AQP2 mutants was also demonstrated in transfected MDCK cells, and using the chaperones TMAO and DMSO in place of glycerol in CHO cells. Water permeability measurements indicated that functional correction was achieved. These results indicate defective mammalian cell processing of mutant AQP2 water channels in NDI, and provide evidence for pharmacological correction of the processing defect by chemical chaperones. 相似文献
997.
Technical Overview of Team DRC‐Hubo@UNLV's Approach to the 2015 DARPA Robotics Challenge Finals 下载免费PDF全文
This paper presents a technical overview of Team DRC‐Hubo@UNLV's approach to the 2015 DARPA Robotics Challenge Finals (DRC‐Finals). The Finals required a robotic platform that was robust and reliable in both hardware and software to complete tasks in 60 min under degraded communication. With this point of view, Team DRC‐Hubo@UNLV integrated methods and algorithms previously verified, validated, and widely used in the robotics community. For the communication aspect, a common shared memory approach that the team adopted to enable efficient data communication under the DARPA controlled network is described. A new perception head design (optimized for the tasks of the Finals) and its data processing are then presented. In the motion planning and control aspect, various techniques, such as wheel‐driven navigation, zero‐moment‐point (ZMP) ‐based locomotion, and position‐based manipulation and controls, are described in this paper. By introducing strategically critical elements and key lessons learned from DRC‐Trials 2013 and the testbed of Charleston, we also illustrate how DRC‐Hubo has evolved successfully toward the DRC‐Finals. 相似文献
998.
Hyeok-jin Kwon Heqing Ye Yonghwa Baek Jisu Hong Rixuan Wang Yonghwan Choi Ilgeum Lee Chan Eon Park Sooji Nam Juyoung Kim Se Hyun Kim 《Advanced functional materials》2021,31(10):2009539
A novel fluorinated organic–inorganic (O–I) hybrid sol—gel based material, named FAGPTi, is successfully synthesized and applied as a gate dielectric in flexible organic thin-film transistors (OTFTs). The previously reported three-arm-shaped alkoxysilane-functionalized amphiphilic polymer yields a stable O–I hybrid material consisting of uniformly dispersed nanoparticles in the sol-state. Here, a fluorinated precursor is introduced into the system, making it possible to realize more stable spherical composites. This results in long-term colloidal stability (≈1.5 years) because composite growth is strongly inhibited by the presence of fluorine groups with intrinsically strong repulsive forces. Additionally, the FAGPTi film is easily deposited via thermally annealed sol–gel reactions; the films can be successfully fabricated through the printing method, and exhibit excellent flexibility and enhanced insulating properties compared to existing materials. OTFTs with FAGPTi layers show highly stable driving characteristics under severe bending conditions (1.9% strain). Integrated logic devices are also successfully operated with these OTFTs. Additionally, it can facilely be applied to amorphous indium-gallium-zinc-oxide (a-IGZO) TFT devices other than OTFT. Therefore, this synthetic strategy can provide useful insights into the production of functional O–I hybrid materials, enabling the efficient fabrication of electronic materials and devices exhibiting these properties. 相似文献
999.
One of the latest technologies enabling remote control, operational efficiency upgrades, and real-time big-data monitoring in an industrial control system (ICS) is the IIoT-Cloud ICS, which integrates the Industrial Internet of Things (IIoT) and the cloud into the ICS. Although an ICS benefits from the application of IIoT and the cloud in terms of cost reduction, efficiency improvement, and real-time monitoring, the application of this technology to an ICS poses an unprecedented security risk by exposing its terminal devices to the outside world. An adversary can collect information regarding senders, recipients, and prime-time slots through traffic analysis and use it as a linchpin for the next attack, posing a potential threat to the ICS. To address this problem, we designed a network traffic obfuscation system (NTOS) for the IIoT-Cloud ICS, based on the requirements derived from the ICS characteristics and limitations of existing NTOS models. As a strategy to solve this problem wherein a decrease in the traffic volume facilitates traffic analysis or reduces the packet transmission speed, we proposed an NTOS based on packet scrambling, wherein a packet is split into multiple pieces before transmission, thus obfuscating network analysis. To minimize the ICS modification and downtime, the proposed NTOS was designed using an agent-based model. In addition, for the ICS network traffic analyzer to operate normally in an environment wherein the NTOS is applied, a rule-based NTOS was adopted such that the actual traffic flow is known only to the device that is aware of the rule and is blocked for attackers. The experimental results verified that the same time requested for response and level of difficulty of analysis were maintained by the application of an NTOS based on packet scrambling, even when the number of requests received by the server per second was reduced. The network traffic analyzer of the ICS can capture the packet flow by using the pre-communicated NTOS rule. In addition, by designing an NTOS using an agent-based model, the impact on the ICS was minimized such that the system could be applied with short downtime. 相似文献
1000.