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排序方式: 共有515条查询结果,搜索用时 171 毫秒
511.
Claire Liu Jin-Tae Kim Da Som Yang Donghwi Cho Seonggwang Yoo Surabhi R. Madhvapathy Hyoyoung Jeong Tianyu Yang Haiwen Luan Raudel Avila Jihun Park Yunyun Wu Kennedy Bryant Min Cho JiYong Lee Jay Young Kwak WonHyoung Ryu Yonggang Huang Ralph G. Nuzzo John A. Rogers 《Advanced functional materials》2023,33(34):2302256
Many recently developed classes of wireless, skin-interfaced bioelectronic devices rely on conventional thermoset silicone elastomer materials, such as poly(dimethylsiloxane) (PDMS), as soft encapsulating structures around collections of electronic components, radio frequency antennas and, commonly, rechargeable batteries. In optimized layouts and device designs, these materials provide attractive features, most prominently in their gentle, noninvasive interfaces to the skin even at regions of high curvature and large natural deformations. Past studies, however, overlook opportunities for developing variants of these materials for multimodal means to enhance the safety of the devices against failure modes that range from mechanical damage to thermal runaway. This study presents a self-healing PDMS dynamic covalent matrix embedded with chemistries that provide thermochromism, mechanochromism, strain-adaptive stiffening, and thermal insulation, as a collection of attributes relevant to safety. Demonstrations of this materials system and associated encapsulation strategy involve a wireless, skin-interfaced device that captures mechanoacoustic signatures of health status. The concepts introduced here can apply immediately to many other related bioelectronic devices. 相似文献
512.
Martins Letícia Matias Peixoto Ricardo André Fiorotti Mendes Júlia Castro 《Clean Technologies and Environmental Policy》2023,25(6):1807-1824
Clean Technologies and Environmental Policy - The inadequate management of waste from the mining industry can lead to several environmental problems. For instance, the extraction of quartzite, an... 相似文献
513.
Intelligent communication technologies beyond the network are proposed by using a new full-duplex protocol. The Media Access Control (MAC) is a data interaction network protocol, which outperforms the IEEE 802.15.4e. This research discusses the planning and execution of full-duplex (FD) pipeline MAC protocol for multihop wireless networks (MWN). The design uses a combination of Radio frequency and baseband methods to realize full-duplexing with smallest impact on cross layer functions. The execution and trial results specify that Pipeline Media Access Control (PiMAC) protocol considerably develops network implementation in terms of transmission protocol (TP) and transmission delay. The advantage of using FD-MAC will increase the range of nodes. Also takes benefit of the FD mode of the antenna, which outperforms additionally 80% for all assessed cases. In this analysis, it was considered of that Psz = 8184 bits and Rc = 1Mbps; that’s, TDATA represents an excellent portion of total UTC. Tests on real nodes displays that the FD theme achieves a median gain of 90% in mixture throughput as equated to half-duplex (HD) theme for MWN. The energy consumption of proposed system method is 29.8% reduced when compared with existing system method. 相似文献
514.
Mariarosa Cavallo Erwan Bossavit Sylvia Matzen Thomas Maroutian Rodolphe Alchaar Tung Huu Dang Adrien Khalili Corentin Dabard Huichen Zhang Yoann Prado Claire Abadie James K Utterback Jean Francois Dayen Mathieu G. Silly Pavel Dudin Jose Avila Emmanuel Lhuillier Debora Pierucci 《Advanced functional materials》2023,33(34):2300846
The design of infrared nanocrystals-based (NCs) photodiodes faces a major challenge related to the identification of barriers with a well-suited band alignment or strategy to finely control the carrier density. Here, this study explores a general complementary approach where the carrier density control is achieved by coupling an NC layer to a ferroelectric material. The up-and-down change in ferroelectric polarization directly impacts the NC electronic structure, resulting in the formation of a lateral pn junction. This effect is uncovered directly using nano X-ray photoemission spectroscopy, which shows a relative energy shift of 115 meV of the NC photoemission signal over the two different up- and down-polarized ferroelectric regions, a shift as large as the open circuit value obtained in the diode stack. The performance of this pn junction reveals enhanced responsivity and reduced noise that lead to a factor 40 increase in the detectivity value. 相似文献
515.
The purpose of this study was to investigate the potential of Continuous Wave UV radiation, applied in a dynamic process, to reduce Enterobacteriaceae counts in powdery and granular foods. Several food matrices were inoculated with a test strain (Escherichia coli LMG 8063) and radiated for 1 h with UV (254 nm, 2.88 mW/cm2). The particles were constantly homogenized under the UV source. Depending on the food matrix, reductions of 0.7–4.8 log cycles were obtained. For meringue chunks, a storage period of 20 h after inoculation prior to UV treatment caused a smaller reduction of the test strain (2.7 log cycles) than when radiation was applied immediately after inoculation (4.8 log cycles). Different initial contamination levels were tested. Higher inoculation levels tended to yield lower reductions. The results demonstrate that Continuous Wave UV radiation can be applied for microbial decontamination of specific powdery and granular food products under continuous homogenization. 相似文献