PL
 |
EN
Preferencje help
Polish version English version Język
Widoczny [Schowaj] Abstrakt
Liczba wyników

Znaleziono wyników: 12

Liczba wyników na stronie
first rewind previous Strona / 1 next fast forward last
Wyniki wyszukiwania
help Sortuj według:

help Ogranicz wyniki do:
first rewind previous Strona / 1 next fast forward last
1
Content available remote Enhanced magnetoelastic performance in Pr/Mn-doped Laves phase (Tb,Ho)Fe2 compounds
Wang M. K., Liu J. J., Lv X. J., Ding Q. L., Li F., Pan Z. B., Xia W. X., Du J.
Materials Science Poland
|
2020
|
Vol. 38, No. 4
707--714
EN
Magnetostrictive TbxHo0.8−xPr0.2Fe1.8Mn0.1 (0 ⩽ x ⩽ 0.20) alloys are prepared by arc-melting and subsequent annealing. The dopant of Pr/Mn introduced into RFe2 compounds effectively stabilizes the forming of single C15 Laves phase at ambient pressure. The easy magnetization direction (EMD) varies when Tb content increases, which is accompanied by a crystalstructural transition. EMD lies along ‹1 0 0› axis for x ⩽ 0.05, rotating to ‹1 1 1› axis for x ⩽ 0.12, with a tetragonal symmetry changing to a rhombohedral one. Magnetocrystalline-anisotropy compensation is obtained with the optimized composition of x = 0.12, shifting to the Tb-poor side in comparison to Pr/Mn-free counterpart. An enhanced effect on magnetoelastic properties is achieved in Tb0.12Ho0.68Pr0.2Fe1.8Mn0.1, which simultaneously possesses a low anisotropy and high magnetostriction performance, i.e. λs ~ 420 ppm, λ111 ~ 970 ppm, and a large low-field λa ~ 390 ppm/2 kOe, being 30 % higher than that of Pr/Mn-free compound. Combining low-cost light rare earth Pr with the lower Tb content, Tb0.12Ho0.68Pr0.2Fe1.8Mn0.1may make it promising solution in magnetostrictive applications.
2
Content available Study on optimization simulation of SCR denitration system for marine diesel engine
Du J., Li R. N., Wu X., Zhang Y.
Polish Maritime Research
|
2018
|
S 3
13--21
EN
With the rapid development of shipbuilding industry exhaust world is also very harmful one kind of environmental issues, and the ship marine diesel engine exhaust gas is mainly produced, so in recent years it has developed a diesel engine SCR system. SCR system can control emissions of nitrogen oxides in the exhaust of vessel, furthermore air pollution can be reduced. The main goal of article was using fluent software to correct SCR system selection and flue gas flow under different size best deflector arrangement is simulated. Next goal is further optimize the structure of the SCR system.
3
Content available Simulation and experimental study of SCR injection system
Du J., Zhang Y., Cai Y.
Polish Maritime Research
|
2018
|
S 2
49--55
EN
According to actual engineering test, we design a linear controlled spray ammonia grille, and apply it to the SCR injection system of ship tail gas treatment. In this paper, the geometric model of ammonia injection grid was built in the flue of diesel engine, and the effects of spray atomization, ammonia uniformity and urea droplet distribution on spray atomization were simulated. Then the test bench was set up to observe the injection status of the ammonia injection grille. The NOx content of the outlet was measured by the original data of the flue gas, and the experimental data were processed. We calculate the denitrification rate by taking the average value to verify the correctness of the spray ammonia grid scheme.
4
Content available Essential norm of an integral-type operator from ω-Bloch spaces to μ-Zygmund spaces on the unit ball
Du J., Zhu X.
Opuscula Mathematica
|
2018
|
Vol. 38, no. 6
829--839
EN
In this paper, we give an estimate for the essential norm of an integral-type operator from ω-Bloch spaces to μ-Zygmund spaces on the unit ball.
5
Content available Numerical investigation of the undrained compression and pull-out capacity of suction foundations in clay
Du J., Du S., Shena S., Yina Z.
Polish Maritime Research
|
2015
|
S 1
126--135
EN
This paper presents the results of three-dimensional finite difference analysis of suction foundations in uniform and non-uniform clays under undrained conditions. The Tresca criterion was used to simulate the stress-strain response. The bearing capacity of the foundations was investigated, with the degree of nonhomogeneity (kD/sum) of soil varying from 0 to 5, and the embedment depth being up to four times the foundation diameter. The end bearing capacity factor in compression and the reverse bearing capacity factor in tension were both calculated and were compared with each other under different foundation displacements. Numerical results showed that the ultimate bearing capacity factor can have the same value in cases of both compression and tension. The recommended ultimate bearing capacity factor is determined on the basis of the embedment ratio and displacement magnitude, and the displacement is not more than 30% of the foundation diameter. Finally, two equations are proposed to evaluate both the bearing capacity factor and the effective depth factor.
6
Content available Enhancing light harvesting of organic solar cells by using hybrid microlenses
Xiao X, Zhang Z, Xie S, Liu Y, Hu D, Du J
Optica Applicata
|
2015
|
Vol. 45, nr 1
89—100
EN
Organic solar cells have drawn intense attentions in recent years due to their inherent advantages. But the relatively low power conversion efficiency is the main obstacle in the way of organic solar cell commercialization. One of the main reasons that limit the power conversion efficiency is the mismatch between electrical transmission properties and light absorption properties in an organic active layer. In this work, a highly efficient light trapping scheme with a hybrid microlens array is proposed to resolve this contradiction. This structure can achieve broadband absorption enhancement in the spectrum of interest by chromatic aberration correction and hole parameter adjustment. And the light trapping element can be separated from cells to avoid direct contact with an organic layer that may cause electrical defects. Moreover, it is also compatible with low cost manufacturing technologies.
7
Content available Effects of Magnesium Powder on the Radiation Characteristics of MTV Foil Infrared Decoys
Du J., Guan H., Li J.
Central European Journal of Energetic Materials
|
2015
|
Vol. 12, no. 4
855--863
EN
The aim of this project was to study how the particle size and morphology of magnesium powder affect the burning and infrared radiation characteristics of foil-type Mg/PTFE/Viton (MTV) infrared decoys. A long-wavelength thermal imager and an OPAG33 Fourier transform infrared remote-sensing spectrometer were used to characterize the burning and infrared radiation. The results show that the burning rate, burning temperature, and far-infrared radiation intensity of the decoys are improved significantly with decreased particle size. The burning rate, burning temperature, and far-infrared radiation intensity of the flake-like powder are higher than for the spherical powder of the same particle size.
8
Content available remote Research and Simulation of a Full-Scale Attitude Algorithm for Strapdown Inertial Navigation Based on a Rotation Vector
Cao Y., Bai Y., Du J., Zhao J.
Przegląd Elektrotechniczny
|
2013
|
R. 89, nr 3b
41--43
EN
The compensation for non-swappable error of traditional quaternion algorithm is not enough in attitude matrix solution. It can only apply to the attitude solution of low dynamic carriers. An optimized algorithm based on a 3-subsample rotation vector is presented. The full-scale attitude of a strapdown inertial navigation system can be calculated through resolving a attitude change quaternion. The algorithm is validated through simulation. The results show that the algorithm can satisfy real-time and precision requirements. The influence of direction drift on the attitude solution of the strapdown inertial navigation system is also reduced.
PL
W artykule przedstawiono zoptymalizowany algorytm kompensacji błędów w podejściu kwaternionowym w metodzie macierzy orientacji, na potrzeby systemu nawigacji bezwładnościowej typu strapdown. Określanie orientacji pełnowymiarowej odbywa się poprzez obliczeniowe rozwiązanie kwaterniona zmiany orientacji. Opracowany algorytm poddano badaniom symulacyjnym, których wyniki potwierdzają skuteczność proponowanego rozwiązania.
9
Content available remote Constraint Voronoi Grid Generation in 2D Arbitrary Domain by Refinement Algorithm
Li H., Zeng Y., Cai Q., Liu Y., Du J.
Przegląd Elektrotechniczny
|
2013
|
R. 89, nr 1b
120--123
EN
In this paper, based on studying the traditional constraint Voronoi diagram generation techniques, an optimized trapezium examining strip refinement algorithm for constraint Voronoi grid generation is presented .First, the initial isosceles trapezoid examining strip sets are settled according to the constraint condition, then by introducing several control factors to subdivide the examining strip to realize the speedy generation of constraint Voronoi grids. Experimental results show the proposed algorithm can get satisfied results even in the complex domain including internal boundary constraints, pencil of lines constraints and irregular areas.
PL
W opracowaniu, w celu wytworzenia siatek Voronoi z ograniczeniami, na podstawie badań tradycyjnej techniki wytwarzania diagramem Voronoi, przedstawiono algorytm rafinacyjny tworzenia trapezowej wstęgi badań. Wstępnie ustalono równomierne trapezowe wstęgi badań zgodnie z warunkami ograniczeń. Następnie, aby przyspieszyć tworzenie siatek, podzielono badane wstęgi przez wprowadzenie kilku współczynników kontroli. Wyniki badań pokazują, że proponowany algorytm daje satysfakcjonujące wyniki w złożonych obszarach, włącznie z ograniczeniami wewnętrznymi granicami i wiązkami linii oraz w przypadku nieregularnych pól.
10
Content available remote Relational Operations and Uncertainty Measure in Rough Relational Database
Jiang F., Sui Y., Cao C., Wan X., Du J.
Fundamenta Informaticae
|
2013
|
Vol. 123, nr 4
401--416
EN
The traditional relational database model (RDM) is not effective for dealing with imprecise and uncertain data as it deals with precise and unambiguous data. Hence, Beaubouef et al. proposed the rough relational database model (RRDM) for the management of uncertainty in relational databases. Beaubouef et al. defined the corresponding rough relational operators in rough relational databases as in ordinary relational databases. And to give an effective measure of uncertainty in rough relational databases, they defined the rough relation entropy. In this paper, we further discuss the issues of relational operations and uncertainty measure in rough relational databases. We give some new definitions for rough relational operators and rough relation entropy in rough relational databases. Furthermore, we discuss the basic properties of rough relational operators and rough relation entropy, as well as the connections between rough relational operators and rough relation entropy.
11
Binding of Cytidine-5'-monophosphate with Human Serum Albumin: Spectroscopic and Molecular Modeling Studies
Cui F. L., Yan Y. H., Zhang Q. Z., Du J., Yao X. J., Qu G. R., Lu Y.
Polish Journal of Chemistry
|
2009
|
Vol. 83, nr 10
1783-1795
EN
The binding of cytidine-5’-monophosphate (CMP) to human serum albumin (HSA) was investigated by fluorescence spectroscopy in combination with molecular modeling under simulation of physiological conditions. The quenching mechanism was suggested to be static according to the fluorescence measurement. The thermodynamic parameters: enthalpy change (DeltaH) and entropy change (DeltaS) were calculated to be –5.09 kJ/mol and 73.00 J mol–1 K–1 according to the Vant’Hoff equation. These data suggest that hydrophobic inter actions are the predominant intermolecular forces stabilizing the complex. Experimental results are in agreement with the results obtained by molecular modeling study. In addition, the effects of commonions on the binding constants were also studied at room temperature.
12
Content available Ergonomics Hazards Analysis of Linemen’s Power Line Fixing Work in China
Yu M., Sun L., Du J., Wu F.
International Journal of Occupational Safety and Ergonomics
|
2009
|
Vol. 15, No. 3
309--317
EN
This study used qualitative and quantitative methods, such as OWAS (Ovako working posture analysis system) and behavior observation, to analyze musculoskeletal disorder (MSD) risk factors of power line fixing work in China. Video-based sampling was used to record and analyze the frequency and posture of on-pole activities. Those key subtasks showed ergonomics characteristics of on-pole fixing tasks. Insulator-fixing was the longest subtask (33% of total working time). Bar-installing was the second longest (26% of total working time). It was evident that bar-installing and insulator-fixing were full of hazardous risks. The action categories of the 2 subtasks were higher than of the other ones. The 2 subtasks were also time-consuming, difficult and induced MSDs. Assistant linemen faced more hazardous factors than chief linemen.
first rewind previous Strona / 1 next fast forward last
JavaScript jest wyłączony w Twojej przeglądarce internetowej. Włącz go, a następnie odśwież stronę, aby móc w pełni z niej korzystać.