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排序方式: 共有171条查询结果,搜索用时 31 毫秒
91.
Dr. Artem Osypenko Dr. Emilie Moulin Odile Gavat Dr. Gad Fuks Prof. Dr. Mounir Maaloum Dr. Mark A. J. Koenis Prof. Dr. Wybren Jan Buma Prof. Dr. Nicolas Giuseppone 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(56):13008-13016
Upon cooling in solution, chiral triarylamine tris-amide unimers produce organogels by stacking into helical supramolecular polymers, which subsequently bundle into larger fibers. Interestingly, circular dichroism, vibrational circular dichroism, and AFM imaging of the chiral self-assemblies revealed that monocolumnar P-helical fibrils formed upon fast cooling, whereas bundled M-superhelical fibers formed upon slow cooling. The mechanistic study of this structural bifurcation reveals the presence of a strong memory effect, reminiscent of a complex stepwise combination of primary and secondary nucleation-growth processes. These results highlight the instrumental role of sequential self-assembly processes to control supramolecular architectures of multiple hierarchical order. 相似文献
92.
Bouzebda Salim Chaouch Mohamed Biha Sultana Didi 《Annals of the Institute of Statistical Mathematics》2022,74(4):737-771
Annals of the Institute of Statistical Mathematics - The main purpose of the present work is to investigate kernel-type estimate of a class of function derivatives including parameters such as the... 相似文献
93.
Mounir Zeitouny Petr Balling Petr Ken Pavel Maika Ronald C. Horsten Stefan T. Persijn H. Paul Urbach Nandini Bhattacharya 《Annalen der Physik》2013,525(6):437-442
An instrument achieving 100 KHz spectral precision using multiple correlation Fourier transform spectroscopy has been demonstrated. The instrument can measure the individual frequency comb modes of 100 MHz frequency comb lasers in air. The experiments show ~400,000 resolved modes at linewidths of 85 MHz in the region of 829 nm and ~ 182,000 resolved modes at linewidths of 28 MHz in the region of 1.5 μm, with a recording time of few minutes. The precision of the instrument, defined by the frequency positioning, attains sub‐MHz even when the scan is performed in air. 相似文献
94.
Magar Hend Samy Abbas Mohammed Nooredeen Ali Mounir Ben Ahmed Mona A. 《Journal of Solid State Electrochemistry》2020,24(3):723-737
Journal of Solid State Electrochemistry - Analysis of saliva is a potential diagnostic tool in the management of human diseases. Analysis of saliva in healthy individuals is vital to comparison in... 相似文献
95.
Theoretical modeling of piezoelectric energy harvesting in the system using technical textile as a support 下载免费PDF全文
Nabil Chakhchaoui Habiba Ennamiri Abdelowahed Hajjaji Adil Eddiai Mounir Meddad Yahia Boughaleb 《先进技术聚合物》2017,28(9):1170-1178
An approach to harvesting electrical energy from a mechanically excited piezoelectric element has been described. The topic of this paper studies the most important properties of piezoelectric polymer polyvinylidene fluoride (PVDF) in energy harvesting. We have chosen to develop a recovery application within the clothes. By the use of a piezoelectric energy harvester capable to convert the mechanical energy produced by the knee during walking to an electrical energy. This will be achieved by replacing the traditional textile of the kneepad with the one that is made of the technical textile based on acrylic knitted and PVDF as a patch stuck on the textile. Furthermore, PVDF has many unique features, such as excellent mechanical behavior, large strain without structure fatigue, which enables it to act strongly as the load bearing member, and corrosion resistance. The technical textile, functioning as multifunctional wearable human interfaces, is considered today as a useful tool in several energy fields. In this paper, a smart structure based on piezoelectric polymer (PVDF) has been presented, which a power analytical model, based on the frequency, the geometrical parameters and other factors were investigated. Furthermore, the set of numerical results illustrating the harvested power for a given size of the device has been performed and discussed and how this harvested power may be used as a source for a wearable device. Finally, the theory presented in this study can be used for the realization of other optimal designs, for a wearable sensor with low consumption and so on. Copyright © 2017 John Wiley & Sons, Ltd. 相似文献
96.
97.
MANSOURI Said MAJDOUBI Hicham HADDAJI Younesse TAMRAOUI Youssef EL ACHABY Mounir MANOUN Bouchaib ABOURRICHE Abdelkrim HANNACHE Hassan OUMAM Mina 《高等学校化学研究》2020,36(6):1339-1347
This paper discusses the elaboration of adsorbents from oil shale. The experimental designs a response surface methodology(RSM), which has been applied to optimize the significant preparation factors, such as temperature, time, and the activating agent percentage. The results obtained from central composite design(CCD) revealed that the interaction between the factors was significant for the maximum quantity of adsorption(response). Planned results have shown that a maximum quantity of adsorption for methylene blue is 65 mg/g, which could be achieved with a temperature of 275℃ over 2 h and a percentage of the activating agent of 45%. The predicted values agreed with the experimental finding, with a determination coefficient(R2) of 0.96. The model has been validated by experiments after conditions optimization. The new material(RHO) was characterized by cation exchange capacity, zero charge pH, surface functions, X-ray fluorescence, specific surface area, and electron microscopy analysis. Phenol adsorption was determined using Langmuir, Freundlich and Temkin, which were used to describe the adsorption isotherms. The adsorption capacity of the material was about 263 mg/g, and the kinetic studies showed rapid adsorption. 相似文献
98.
99.
Ion channels constitute an important family of integral membrane proteins responsible for the regulation of ion transport across the cell membrane. Yet, the underlying energetics of the permeation events and how the latter are modulated by the environment, specifically near the mouth of the pore, remain only partially characterized. Here, a synthetic membrane channel formed by cyclic peptides of alternated d- and l-hydrophobic alpha-amino acids was considered. The free energy delineating the translocation of a sodium ion was measured along the conduction pathway by means of molecular dynamics simulations. The free-energy profiles that underly the permeation of the open-ended tubular structure are shown to not only depend on the characteristics of the latter but also inherently on the location of the mouth of the synthetic channel with respect to the membrane surface. 相似文献
100.
Mounir Andaloussi Emmanuel Moreau Olivier Chavignon Jean C. Teulade 《Tetrahedron letters》2007,48(47):8392-8395
Two new imidazo[1,2-a]pyridine derivatives, pyridinoimidazo[1,2-a]pyridine (10) and pyrroloimidazo[1,2-a]pyridine (16), were synthesised from 2-amino-4-methyl-5-nitropyridine (1) by linear cyclisation, making use of dimethylformamide dimethylacetal (DMFDMA) as an agent of vinylamine functionalisation. This report describes first the formation of pyridine and pyrroloimidazopyridine from (1), and then the formation of pyridine-fused and pyrrolo-fused pyridine by the Friedländer method and reductive cyclisation followed by treatment of the resulting adduct with chloroacetaldehyde. 相似文献