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排序方式: 共有193条查询结果,搜索用时 15 毫秒
101.
Yan Zhang Margaret A. Hopkins David J. Liptrot Hamideh Khanbareh Pim Groen Xuefan Zhou Dou Zhang Yinxiang Bao Kechao Zhou Chris R. Bowen David R. Carbery 《Angewandte Chemie (International ed. in English)》2020,59(20):7808-7812
We demonstrate that trimethylamine borane can exhibit desirable piezoelectric and pyroelectric properties. The material was shown to be able operate as a flexible film for both thermal sensing, thermal energy conversion and mechanical sensing with high open circuit voltages (>10 V). A piezoelectric coefficient of d33≈10–16 pC N?1, and pyroelectric coefficient of p≈25.8 μC m?2 K?1 were achieved after poling, with high pyroelectric figure of merits for sensing and harvesting, along with a relative permittivity of 6.3. 相似文献
102.
Seyed Javad Hosseininezhad Mohammad Saeed JabalameliSeyed Gholamreza Jalali Naini 《Applied Mathematical Modelling》2014
This paper presents a continuous capacitated location-allocation model with fixed cost as a risk management model. In the presented model, the fixed cost consists of production and installation costs. The model considers risk as percent of unsatisfied demands. The fixed cost is assigned to a zone with a predetermined radius from its center. Because of uncertain environment, demand in each zone is investigated as a fuzzy number. The model is solved by a fuzzy algorithm based on α-cut method. After solving the model based on different α-values, the zones with the largest possibilities are determined for locating new facilities and the best locations are calculated based on the obtained possibilities. Then, the model is solved based on different α-values to determine best allocation values. Also, this paper proposes a Cross Entropy (CE) algorithm considering multivariate normal and multinomial density functions for solving large scale instances and is compared with GAMS. Finally, a numerical example is expressed to illustrate the proposed model. 相似文献
103.
B. Jalali D.R. Solli K. Goda K. Tsia C. Ropers 《The European physical journal. Special topics》2010,185(1):145-157
Rogue events otherwise known as outliers and black swans are singular, rare, events that carry dramatic impact. They appear
in seemingly unconnected systems in the form of oceanic rogue waves, stock market crashes, evolution, and communication systems.
Attempts to understand the underlying dynamics of such complex systems that lead to spectacular and often cataclysmic outcomes
have been frustrated by the scarcity of events, resulting in insufficient statistical data, and by the inability to perform
experiments under controlled conditions. Extreme rare events also occur in ultrafast physical sciences where it is possible
to collect large data sets, even for rare events, in a short time period. The knowledge gained from observing rare events
in ultrafast systems may provide valuable insight into extreme value phenomena that occur over a much slower timescale and
that have a closer connection with human experience. One solution is a real-time ultrafast instrument that is capable of capturing
singular and randomly occurring non-repetitive events. The time stretch technology developed during the past 13 years is providing
a powerful tool box for reaching this goal. This paper reviews this technology and discusses its use in capturing rogue events
in electronic signals, spectroscopy, and imaging. We show an example in nonlinear optics where it was possible to capture
rare and random solitons whose unusual statistical distribution resemble those observed in financial markets. The ability
to observe the true spectrum of each event in real time has led to important insight in understanding the underlying process,
which in turn has made it possible to control soliton generation leading to improvement in the coherence of supercontinuum
light. We also show a new class of fast imagers which are being considered for early detection of cancer because of their
potential ability to detect rare diseased cells (so called rogue cells) in a large population of healthy cells. 相似文献
104.
Ricardo Claps Dimitrios Dimitropoulos Bahram Jalali Bernard Jusserand 《Superlattices and Microstructures》2006,39(6):501-516
This paper discusses the design of acoustic vibrational modes in Si/Ge planar optical waveguides and its application in creating silicon-based Raman devices with a flexible spectrum. It addresses the deficiencies of the recently demonstrated Raman-based silicon lasers and amplifiers as they relate to spectral and low efficiency limitations of bulk silicon. The treatment is for in-plane scattering in a forward scattering configuration. In addition to calculating the spectrum and the efficiency for Raman active modes, it is shown that the negligible wave-vector of the phonons involved in this type of scattering allows for the use of the bandgap “pinching” effect to arrive at specific layer thicknesses for Si and Ge that optimize the scattering efficiency. 相似文献
105.
Hamideh B. Mohammadi Amin Esfahani 《Mathematical Methods in the Applied Sciences》2019,42(8):2854-2876
In this paper, we study the Cauchy problem for the generalized Boussinesq‐type equation with strong damping. By defining a suitable solution space with time‐weighted norms and under smallness condition on the initial data, we establish the global existence and decay property of the solutions. Under certain conditions on the initial data, we also provide blowup of the solutions. 相似文献
106.
We report on a fast, simple and accurate method for the determination of proline in urine samples by employing a nanostructured film of conducting polypyrrole for electrochemically controlled solid-phase microextraction, and ion mobility spectrometry (IMS) for detection. This method has the advantages of simple sample preparation and a sensitivity of IMS to proline that is higher than that for other amino acids. The calibration curve is linear in the range of 0.5–60 μg L?1 (4–521 nmol L?1), and the detection limit is 0.2 μg L?1. The electrochemical potentials for uptake and release were optimized. The method was successfully applied to the clean-up and quantitation of trace amounts of proline in urine samples. Figure
Proline determination by electrochemically controlled solid phase microextraction coupled to ion mobility spectrometry 相似文献
107.
A. D. Khalaji H. Mighani M. Gholinejad G. Grivani S. Jalali Akerdi K. Fejfarova M. Dusek 《Journal of Structural Chemistry》2013,54(4):766-773
In this study four coordinated complexes of zinc(II) halides with a new symmetrical bidentate Schiff base ligand (2,5-MeO-ba)2En are synthesized and characterized. The metal to ligand ratio of the complexes is found to be 1:1 with the formula of Zn((2,5-MeO-ba)2En)X2 (X = Cl (1), Br (2), I (3)). The crystal structure of the Schiff base ligand (2,5-MeO-ba)2En is determined by X-ray crystallography from single crystal data. Also, the optimized geometries of the Schiff base ligand (2,5-MeO-ba)2En and its zinc(II) complexes are calculated using the density functional theory method (B3LYP/6-31G). The obtained structural parameters of (2,5-MeO-ba)2En are in agreement with the experimental data. 相似文献
108.
109.
Rapid granular shear flow is a classical example in granular materials which exhibits fluid-like behavior solely or fluid-like and solid-like behaviors simultaneously. We have performed experiments on annular granular shear flows using monodisperse steel spheres with 2-mm and 3-mm diameters. We discuss some transient (static failure of material due to shear) and steady-state (completely sheared and partially sheared flows) features of rapid granular flows. Our results map out the boundary between overall compaction and dilation that characterizes multiphase behavior of the system. Dimensionless stresses rise as more material is loaded into the system. On the other hand, increasing the compressive force or shear rate is equal to easing the process of shearing by decreasing the ratio of shear to normal stress. 相似文献
110.
Gholamreza Nikbakht Brujeni Sayed Amir Hossein Jalali Mohammad Kazem Koohi 《Applied biochemistry and biotechnology》2011,163(3):338-345
Interferon-gamma (IFN-γ), a cytokine produced by sensitized T lymphocytes, is one of the key elements in defining T helper
1 lymphocyte immune responses. Quantitative evaluation of IFN-γ expression could provide an important analytical tool for
measurement of cell-mediated immunity and investigating immune responses to infectious diseases. Method of DNA-designed avian
IgY antibodies was used for production of monospecific polyclonal antibodies that allows quantification of the recombinant
bovine IFN-γ protein. IFN-γ cDNA was subcloned and expressed in mammalian expression plasmid (pcDNA3.1(+)) under the control
of the human cytomegalovirus promoter. Chickens were immunized by plasmid DNA, and eggyolk antibodies extracted from eggs
were collected after immunization. IgY-specific antibodies were evaluated by an antigen capture enzyme-linked immunosorbent
assay (ELISA) using recombinant IFN-γ. Based on the results, developed bovine IFN-γ capture ELISA could detect up to 1 ng/ml
of IFN-γ by 64-fold diluted IgY. Monospecific anti-bovine IFN-γ antibodies generated in chickens are useful for quantifying
different concentrations of recombinant bovine IFN-γ, which is expressed in cell culture. 相似文献