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排序方式: 共有810条查询结果,搜索用时 31 毫秒
802.
803.
Matthew Rogers Ahasan Habib Gilberto Teobaldi Timothy Moorsom J. Olof Johansson Luke Hedley Paul S. Keatley Robert J. Hicken Manuel Valvidares Pierluigi Gargiani Nader Alosaimi Emiliano Poli Mannan Ali Gavin Burnell Bryan J. Hickey Oscar Cespedes 《Advanced functional materials》2023,33(13):2212173
The long-term future of information storage requires the use of sustainable nanomaterials in architectures operating at high frequencies. Interfaces can play a key role in this pursuit via emergent functionalities that break out from conventional operation methods. Here, spin-filtering effects and photocurrents are combined at metal-molecular-oxide junctions in a hybrid magneto-capacitive memory. Light exposure of metal-fullerene-metal oxide devices results in spin-polarized charge trapping and the formation of a magnetic interface. Because the magnetism is generated by a photocurrent, the writing time is determined by exciton formation and splitting, electron hopping, and spin-dependent trapping. Transient absorption spectroscopy measurements show changes in the electronic states as a function of the magnetic history of the device within picoseconds of the optical pumping. The stored information is read using time-resolved scanning magneto optic Kerr effect measurements during microwave irradiation. The emergence of a magnetic interface in the picosecond timescale opens new paths of research to design hybrid magneto-optic structures operating at high frequencies for sensing, computing, and information storage. 相似文献
804.
805.
Warming temperatures can have negative consequences for aquatic organisms, especially cold-adapted fishes such as Pacific salmon. The magnitude of warming is related to the thermal sensitivity of streams in salmon-bearing watersheds (i.e., change in stream temperature for every 1°C increase in air temperature), which can vary based on several factors including streamflow. Management actions to increase streamflow may therefore benefit salmon by decreasing thermal sensitivity. However, the effects of streamflow on thermal sensitivity are often complex, as the temperature of flow inputs can directly increase or decrease temperatures. This study aimed to disentangle the influence of streamflow on thermal sensitivity and stream temperature over 4 years in the Nicola River, a regulated semiarid watershed in south-central British Columbia, Canada. A statistical modeling approach was used to estimate streamflow effects on stream temperatures and thermal sensitivity (i.e., relationship of regional air temperature to stream temperature) at 12 sites from 2018 to 2021. Streamflow had a variable influence on stream temperatures across the watershed via both direct effects and by modulating thermal sensitivity. At a given site, streamflow was generally negatively associated with summer daily mean stream temperature, but the magnitude of its influence varied among locations and years. The influence of streamflow on thermal sensitivity was also highly variable both spatially and temporally. The analysis suggests that there may be complex relationships between streamflow, stream temperature, and thermal sensitivity, which complicates the efficacy of flow as a lever to mitigate high temperatures in regulated systems. 相似文献
806.
Tang Wei Fancher Chris M. Nandwana Peeyush An Ke Nycz Andrzej Wang Hsin Kannan Rangasayee Trofimov Artem Yu Dunji Leonard Donovan N. Meyer Luke Plotkowski Alex 《Metallurgical and Materials Transactions A》2023,54(3):854-868
Metallurgical and Materials Transactions A - Recent research has studied the use of low transformation temperature (LTT) martensite steel as feedstock for wire arc additive manufacturing (WAAM) and... 相似文献
807.
Alexa Ennis Deanna Nicdao Srikanth Kolagatla Luke Dowling Yekaterina Tskhe Alex J. Thompson Daniel Trimble Colm Delaney Larisa Florea 《Advanced functional materials》2023,33(39):2213947
Stimuli-responsive hydrogels have attracted much attention owing to the versatility of their programmed response in offering intelligent solutions for biomimicry applications, such as soft robotics, tissue engineering, and drug delivery. To achieve the complexity of biomimetic structures, two photon polymerization (2PP) has provided a means of fabricating intricate 3D structures from stimuli-responsive hydrogels. Rapid swelling hydrogel microstructures are advantageous for osmotically driven stimuli-response, where actuation speed, that is reliant on the diffusion of analytes or bioanalytes, can be optimized. Herein, the flexibility of 2PP is exploited to showcase a novel sugar-responsive, phenylboronic acid-based photoresist. This offers a remarkable solution for achieving fast response hydrogel systems that have been often hindered by the volume-dependent diffusion times of analytes to receptor sites. A phenylboronic acid-based photoresist compatible with 2PP is presented to fabricate stimuli-responsive microstructures with accelerated response times. Moreover, microstructures with programmable actuation (i.e., bending and opening) are fabricated using the same photoresist within a one-step fabrication process. By combining the flexibility of 2PP with an easily adaptable photoresist, an accessible fabrication method is showcased for sophisticated and chemo-responsive 3D hydrogel actuators. 相似文献
808.
Samuel Ruiz Yongchul Yoo Luke Wadle Xin Chen Nan Li Yongfeng Lu Christopher J. Wohl Valerie Wiesner Bai Cui 《Journal of the American Ceramic Society》2023,106(10):5712-5722
Through a novel laser ablative patterning (LAP) process, the present work reported the increase in wetting contact angle of two ceramic materials, boron carbide (B4C) and molybdenum aluminum boride (MoAlB). The LAP technique employed picosecond laser pulses to form a crosshatch pattern with micropillars on ceramic surfaces. The wetting behavior of both ceramic surfaces was successfully transitioned from hydrophilic (θ < 90°) to hydrophobic (θ > 90°), which was related to Wenzel and Cassie–Baxter mechanisms. Parameters such as laser fluence and number of laser scans were varied to study their effects on ceramic surface characteristics. Lunar dust adhesion experiments were performed on these hydrophobic ceramic surfaces, which showed that the adhesion of lunar soil simulant dust particles was significantly reduced in the patterned B4C and MoAlB surfaces. 相似文献
809.
Hendrik Margraf Marian Lottis Mohammad Deeb Univ.-Prof. Dr.-Ing. habil. Andrea Luke 《化学,工程师,技术》2023,95(5):717-723
A heat transport system based on heat pipes is developed and analyzed. The aim is to increase the efficiency of electrical engines by transferring dissipation-related heat. The system performance is investigated experimentally by varying the temperature range and the supplied heat flow as well as the rotational speed. The thermal resistance of the system is reduced by 98 % compared to pure heat conduction. The rotation of the system has no significant influence on the thermal resistance, which is constant until the power limit is reached. The power limit is dependent on temperature and approximately coincides with the capillary force limit. 相似文献
810.
Luke Anthony Fiorini 《人机工程学与制造业中的人性因素》2023,33(5):357-365
Teleworking, also known as remote working, has become the new norm for many workers since the coronavirus disease 2019 (COVID-19) pandemic. Studies show that during this time, the incidence of musculoskeletal pain is increasing among these workers. Despite this, few studies have addressed the possible correlates of musculoskeletal paśin in teleworkers, with several potential predictors receiving little or no attention in published studies. With this in mind, an online survey was conducted among organizations in the IT and communications sectors in Malta. Information was collected from 459 teleworkers on the frequency of telework, frequency of work during nonworking hours, exercise frequency, burnout, and ergonomic arrangements. Demographic data were also collected. Results revealed that 55.8% reported one or more musculoskeletal pain. Back pain was the most common, followed by neck and shoulder pain. The presence of pain, the number of painful body areas, and the presence of back, neck, and shoulder pain were each individually associated with work during nonworking hours, lower levels of exercise, and higher levels of burnout. It is argued that musculoskeletal pain appears to be common among teleworkers and may negatively impact the quality of life and organizational performance. Companies and occupational health practitioners should strive to identify the prevalence of these problems among their teleworkers, develop appropriate preventive measures, and support workers to obtain multidisciplinary care when needed. 相似文献