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排序方式: 共有392条查询结果,搜索用时 15 毫秒
381.
Donghwan Kim Hoang Tran Thi Thuy Byeonggwan Kim Yanghyun Auh Maxime Rémond Kwang Keat Leong Ting Liang Jinbo Kim Eunkyoung Kim 《Advanced functional materials》2023,33(3):2208157
Synergistically enhancing luminescent and ferroelectric ( SELF ) properties are observed from a tetraphenylethene ( TP ) substituted with clipping groups ( C ), where the C is consisting of a 4-[3,5-bis-(3-decyloxy-styryl)-styryl]-phenyl ( DOS ) unit. The DOS units of TPCn are self-assembled via intermolecular interaction to clip themselves and induce TP aggregation, as evidenced by clip-induced quenching of emission at DOS units ( E clip ) accompanied by aggregation-induced emission enhancement of TPs ( E AIE ). TPC4 demonstrates strong photoluminescence in a dilute chloroform solution and large EAIE in aqueous (>50%) THF solution. TPCn demonstrates SELF properties in film state, with high quantum yields of photoluminescence (>80%) and ferroelectric switching. Due to the introduction of four clips, TPC4 has a higher remnant polarization ( P r = 2.27 µC cm−2) at room temperature than TPC1. TPC4 is successfully employed in a light-emitting electrochemical cell to achieve over 1290 cd m−2 under pulsed current conditions. The TPC4 film on a flexible substrate produced a piezoelectric output voltage of up to 0.13 V and a current density of 1.14 nA cm−2 upon bending. These results indicate that the side chain clipping and TP aggregation resulted in unprecedented flexible SELF properties in a single compound, offering simultaneous enhancement of electroluminescence, mechanical sensitivity, and energy harvesting capacity. 相似文献
382.
Edgar Bautista Quisbert François Fauth Artem M. Abakumov Maxime Blangero Marie Guignard Claude Delmas 《Small (Weinheim an der Bergstrasse, Germany)》2023,19(30):2300616
Nickel-rich layered oxides are adopted as electrode materials for EV's. They suffer from a capacity loss when the cells are charged above 4.15 V versus Li/Li+. Doping and coating can lead to significant improvement in cycling. However, the mechanisms involved at high voltage are not clear. This work is focused on LiNiO2 to overcome the effect of M cations. Galvanostatic intermittent titration technique (GITT) and in situ X-ray diffraction (XRD) experiments are performed at very low rates in various voltage ranges (3.8–4.3 V,). On the “4.2–4.3 V” plateau the R2 phase is transformed simultaneously in R3, R3 with H4 stacking faults and H4. As the charge proceeds above 4.17 V cell polarization increases, hindering Li deintercalation. In discharge, such polarization decreases immediately. Upon cycling, the polarization increases at each charge above 4.17 V. In discharge, the capacity and dQ/dV features below 4.1 V remain constant and unaffected, suggesting that the bulk of the material do not undergo significant structural defect. This study shows that the change in polarization results from the electrochemical behavior of the grain surface having very low conductivity above 4.17 V and high conductivity below this threshold. This new approach can explain the behavior observed with dopants like tungsten. 相似文献
383.
Hydropeaking due to hydropower production can have negative impacts on aquatic fauna. One of the mechanisms for causing impacts on fish and aquatic macroinvertebrates is linked to the rapid dewatering of habitats, which can result in stranding or trapping. The magnitude of these impacts depends both on the characteristics of the flow variations and of the river morphology, as well as biological parameters (species, behavior, etc). When discharge is rapidly reduced, the risk of impacts on fishes (and notably the risk of fish stranding in dewatered zones along the riverbank) is frequently assessed by calculations of vertical ramping velocity among other methods. However, to assess fish stranding risks, the lateral ramping velocity calculated as a horizontal ramping rate (HRR) appears to be a more relevant indicator as it directly measures shoreline drawdown rates. HRR has the advantage of integrating river morphology, but it remains challenging to calculate HRRs in complex situations such as braided rivers. Using hydraulic simulations of the Durance, a gravel bed braided river, we have developed an innovative approach for HRR calculation. Considering two simulated flows, the algorithms for the calculations require partitioning the finite elements into wet and drying meshes. To recommend rates of lowering discharges during hydropeaking events, further studies are required to evaluate more precisely HRR limits for fish stranding regarding biotic and abiotic parameters: species, sizes, nychthemeral cycles, temperature, substrate, and so forth. 相似文献
384.
This paper presents the results of twenty-one fire tests on unprotected steel-to-timber connections with dowel-type fasteners and one or two slotted-in steel plates. The experimental results of this type of connections available in existing studies have been mostly limited to a fire resistance duration of 60 min. The tests performed in this study target a significant increase of fire resistance to reach 90 and 120 min. Two configurations of connections with one and two slotted-in steel plates, i.e., two or four shear planes, were tested. The temperatures were measured at different locations in the wood members and along the steel plates. Two load levels for fire tests were determined on the basis of tests performed at ambient temperature. The experimental results show that the specimens proposed for steel-to-timber connections with dowel-type fasteners are suitable for achieving fire resistance of 90 and 120 min. 相似文献
385.
Junjin Che Cécile Zakri Maxime Bronchy Wilfrid Neri Isabelle Ly Philippe Poulin Jinkai Yuan 《Advanced functional materials》2023,33(37):2301544
Due to the low energy density of commercial printable dielectrics, printed capacitors occupy a significant printing area and weight in printed electronics. It has long remained challenging to develop novel dielectric materials with printability and high-energy storage density. Herein, a novel strategy for inkjet printing of all aqueous colloidal inks to dielectric capacitors composed of carbon nanotube electrodes and polyvinylidene fluoride (PVDF)-based dielectrics is presented. The formulated dielectric ink is composed of negatively charged PVDF latex nanoparticles complexed with cationic chitosan molecules. Beyond the isoelectric point, the PVDF@Chitosan particles demonstrate excellent printability and film-forming properties. Chitosan serves as a strong binder to improve the printed film quality yet it introduces charged species. To mitigate the transport of mobile charges, the printed PVDF@Chitosan film is interlayered with a layer of boron nitride nanosheets. This layer is perpendicular to the electric field and serves as an efficient barrier to block the transport and the avalanche of charges, eventually leading to a recoverable energy density of 15 J cm−3 at 610 MV m−1. This energy density represents the highest value among the waterborne dielectrics. It is also superior to most of the state-of-the-art dielectric materials printed from solvent-based formulations. 相似文献
386.
Émilie Thibault Moncef Chioua Maxime McKay Milan Korbel Gregory S. Patience Paul R. Stuart 《加拿大化工杂志》2023,101(11):6055-6078
Industrial facilities collect large volumes of data, store them according to prescribed protocols, and then interpret them for process decision-making. Several sources and types of error contaminate these data for various reasons, but especially because they come from unreliable or unpredictable instruments. Data (or signal) processing corrects measurement errors to improve fidelity. Here, we highlight decision-making applications and signal processing methods. To fully appreciate the state-of-the-art, we interviewed plant data experts and software developers in the pulp and paper industry to examine how they apply signal processing methods in the context of decision-making, including the value of process data, how these data are used, and the major barriers that prevent plants from using data. Process experts clean data thoroughly with basic approaches compared to the advanced techniques available in the recent literature. The interviews demonstrate that decisions in industry are primarily based on steady-state process operating data. Challenges and barriers that prevent the use of process data to their full potential relate to resource limitations (people, time, and money), an entrenched culture, and access to recent technology. In practice, experts consider, implicitly or explicitly, data that represent the process operating under steady-state conditions. A plant model that represents steady-state operations is easier to interpret, is presented in a form that is usable by plant operators, and in this way, better enables decision-making. 相似文献
387.
Dr. Mohamed Ettaoussi Amélie Laversin Brandon Vreulz Dr. Marouane Rami Dr. Nicolas Lebegue Dr. Philippe Delagrange Dr. Daniel Henri Caignard Prof. Patricia Melnyk Dr. Maxime Liberelle Dr. Saïd Yous 《ChemMedChem》2022,17(3):e202100658
In our constant search for new successors of agomelatine, we report herein a new series of compounds resulting from bioisosteric modulation of the naphthalene ring. The isoquinoline and tetrahydroisoquinoline derivatives were synthesized and pharmacologically evaluated. This isosteric replacement of the naphthalene group of agomelatine has led to potent agonist and partial agonist compounds with nanomolar melatonergic binding affinities. Overall, the presence of a nitrogen atom was accompanied with a decrease in the binding affinity toward both MT1 and MT2 and the loss of 5HT2C response, especially for tetrahydroisoquinoline in comparison with the parent compound. Interestingly, due to the presence of this nitrogen atom, a notable improvement in the pharmacokinetic properties was observed for all compounds. 相似文献
388.
Fiacre Rougieux Christian Samundsett Kean Chern Fong Andreas Fell Peiting Zheng Daniel Macdonald Julien Degoulange Roland Einhaus Maxime Forster 《Progress in Photovoltaics: Research and Applications》2016,24(5):725-734
High efficiency solar cells have been fabricated with wafers from an n‐type Czochralski grown (Cz) ingot using 100% Upgraded Metallurgical‐Grade (UMG) silicon feedstock. The UMG cells fabricated with a passivated emitter and rear totally diffused (PERT) structure have an independently confirmed cell efficiency of 19.8%. This is the highest efficiency reported for a cell based on 100% UMG silicon at the time of publication. The current and power losses are analysed as a function of measured material parameters, including carrier mobility, lifetime and the presence of the boron–oxygen defect. Dopant compensation is shown to reduce both the minority carrier lifetime and mobility, which significantly affects both the current and voltage of the device. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
389.
390.
This paper addresses an inventory regulation problem in bicycle sharingsystems. The problem is to balance a network consisting of a set of stations by
using a single vehicle, with the aim of minimizing the weighted sum of the
waiting times during which some stations remain imbalanced. Motivated by the
complexity of this problem, we propose a two-stage procedure based on
decomposition. First, the network is divided into multiple zones by using two
different clustering strategies. Then, the balancing problem is solved in each
zone. Finally, the order in which the zones must be visited is defined. To solve
these problems, different algorithms based on approximate, greedy and exact
methods are developed. The numerical results show the effectiveness of the
proposed regulation methodology. 相似文献