830 research outputs found
DEM simulation of the mechanical properties of SiC ceramic under pre-stressing
In this paper, the method of discrete element model (DEM) simulation was used to investigate the mechanical properties of SiC ceramic materials under the action of pre-stress. Using the bonded particle model (BPM), several different numerical tests (such as UCT, TPB, SENB tests) of SiC ceramic were established. Different pre-stress values were applied on the lateral surface of the ceramic specimen during the numerical simulation process, all tests were carried out at least 5 times with different random number, and the average mechanical properties results were calculated. It was showed that the existence of pre-stress has a significant effect on the mechanical properties of materials. It can enhance the strength of materials, while the force action on material in machining process force or action force the crackβs initiation and propagation was limited
Analysis and design of power management scheme for an on-board solar energy storage system
This paper investigates the power management issues in a mobile solar energy storage system. A multi-converter based energy storage system is proposed, in which solar power is the primary source while the grid or the diesel generator is selected as the secondary source. The existence of the secondary source facilitates the battery state of charge detection by providing a constant battery charging current. Converter modeling, multi-converter control system design, digital implementation and experimental verification are introduced and discussed in details. The prototype experiment indicates that the converter system can provide a constant charging current during solar converter maximum power tracking operation, especially during large solar power output variation, which proves the feasibility of the proposed design
Numerical Simulation-Based Optimization of Contact Stress Distribution and Lubrication Conditions in the Straight Worm Drive
Tooth contact area optimization/meshing of the straight worm pair is vital for improving its operation efficiency. Geometric parameters of a worm helicoid were derived via the gear meshing theory using the equations of the instantaneous contact line. The visualization function and powerful computing capability of MATLAB are used for the numerical analysis where the instantaneous contact line distribution is simulated for particular worm drive parameters, which yields the induced curvature and slip angle in the direction of the line. The above results are used for further optimization of the meshing performance of the straight worm gear and identification of its influencing factors. A case study of the particular cylindrical worm gear in compliance with the GB 10085-1988 Standard of China demonstrate that a reasonable selection of worm gear parameters can extend the contact line and the working range of the tooth surface of the worm gear and/or make the contact line distribution along the worm wheel more uniform, thus improving the local meshing performanceΠΠΏΡΠΈΠΌΠΈΠ·Π°ΡΠΈΡ Π·ΡΠ±ΡΠ°ΡΠΎΠΉ ΠΊΠΎΠ½ΡΠ°ΠΊΡΠ½ΠΎΠΉ ΠΏΠΎΠ²Π΅ΡΡ
Π½ΠΎΡΡΠΈ/Π·Π°ΡΠ΅ΠΏΠ»Π΅Π½ΠΈΠ΅ ΠΏΡΡΠΌΠΎΠ»ΠΈΠ½Π΅ΠΉΠ½ΠΎΠΉ ΡΠ΅ΡΠ²ΡΡΠ½ΠΎΠΉ ΠΏΠ°ΡΡ ΠΎΠΏΡΠ΅Π΄Π΅Π»ΡΡΡ ΠΏΠΎΠ²ΡΡΠ΅Π½ΠΈΠ΅ ΡΡΡΠ΅ΠΊΡΠΈΠ²Π½ΠΎΡΡΠΈ Π΅Π΅ ΡΠΊΡΠΏΠ»ΡΠ°ΡΠ°ΡΠΈΠΈ. ΠΠ΅ΠΎΠΌΠ΅ΡΡΠΈΡΠ΅ΡΠΊΠΈΠ΅ ΠΏΠ°ΡΠ°ΠΌΠ΅ΡΡΡ ΡΠ΅ΡΠ²ΡΡΠ½ΠΎΠ³ΠΎ Π³Π΅Π»ΠΈΠΊΠΎΠΈΠ΄Π° ΠΏΠΎΠ»ΡΡΠ΅Π½Ρ Ρ ΠΈΡΠΏΠΎΠ»ΡΠ·ΠΎΠ²Π°Π½ΠΈΠ΅ΠΌ ΡΠ΅ΠΎΡΠΈΠΈ Π·Π°ΡΠ΅ΠΏΠ»Π΅Π½ΠΈΡ Π·ΡΠ±ΡΠ°ΡΡΡ
ΠΊΠΎΠ»Π΅Ρ ΠΈ ΡΡΠ°Π²Π½Π΅Π½ΠΈΡ Π»ΠΈΠ½ΠΈΠΈ ΠΌΠ³Π½ΠΎΠ²Π΅Π½Π½ΠΎΠ³ΠΎ ΠΊΠΎΠ½ΡΠ°ΠΊΡΠ°. Π§ΠΈΡΠ»Π΅Π½Π½ΡΠΉ Π°Π½Π°Π»ΠΈΠ· ΠΎΡΠ½ΠΎΠ²Π°Π½ Π½Π° ΡΡΠ½ΠΊΡΠΈΠΈ Π²ΠΈΠ·ΡΠ°Π»ΠΈΠ·Π°ΡΠΈΠΈ ΠΈ Π²ΡΡΠΈΡΠ»ΠΈΡΠ΅Π»ΡΠ½ΡΡ
Π²ΠΎΠ·ΠΌΠΎΠΆΠ½ΠΎΡΡΡΡ
ΠΏΡΠΎΠ³ΡΠ°ΠΌΠΌΡ MATLAB, ΡΡΠΎ ΠΏΠΎΠ·Π²ΠΎΠ»ΡΠ΅Ρ ΠΌΠΎΠ΄Π΅Π»ΠΈΡΠΎΠ²Π°ΡΡ ΡΠ°ΡΠΏΡΠ΅Π΄Π΅Π»Π΅Π½ΠΈΠ΅ Π½Π° Π»ΠΈΠ½ΠΈΠΈ ΠΌΠ³Π½ΠΎΠ²Π΅Π½Π½ΠΎΠ³ΠΎ ΠΊΠΎΠ½ΡΠ°ΠΊΡΠ° Π΄Π»Ρ ΡΠΏΠ΅ΡΠΈΡΠΈΡΠ΅ΡΠΊΠΈΡ
ΠΏΠ°ΡΠ°ΠΌΠ΅ΡΡΠΎΠ² ΡΠ΅ΡΠ²ΡΡΠ½ΠΎΠ³ΠΎ ΠΏΡΠΈΠ²ΠΎΠ΄Π°, ΡΠΎΠ·Π΄Π°Π²Π°Ρ Π²ΡΠ½ΡΠΆΠ΄Π΅Π½Π½ΡΡ ΠΊΡΠΈΠ²ΠΈΠ·Π½Ρ ΠΈ ΡΠ³ΠΎΠ» ΡΠΊΠΎΠ»ΡΠΆΠ΅Π½ΠΈΡ Π² Π½Π°ΠΏΡΠ°Π²Π»Π΅Π½ΠΈΠΈ ΡΡΠΎΠΉ Π»ΠΈΠ½ΠΈΠΈ. ΠΠΎΠ»ΡΡΠ΅Π½Π½ΡΠ΅ ΡΠ΅Π·ΡΠ»ΡΡΠ°ΡΡ ΠΎΠ±Π΅ΡΠΏΠ΅ΡΠΈΠ²Π°ΡΡ ΠΏΠΎΡΠ»Π΅Π΄ΡΡΡΡΡ ΠΎΠΏΡΠΈΠΌΠΈΠ·Π°ΡΠΈΡ ΠΏΠ°ΡΠ°ΠΌΠ΅ΡΡΠΎΠ² Π·Π°ΡΠ΅ΠΏΠ»Π΅Π½ΠΈΡ ΠΏΡΡΠΌΠΎΠ»ΠΈΠ½Π΅ΠΉΠ½ΠΎΠΉ ΡΠ΅ΡΠ²ΡΡΠ½ΠΎΠΉ ΠΏΠ΅ΡΠ΅Π΄Π°ΡΠΈ ΠΈ ΡΡΡΠ°Π½ΠΎΠ²Π»Π΅Π½ΠΈΠ΅ ΠΎΠΏΡΠ΅Π΄Π΅Π»ΡΡΡΠΈΡ
ΡΠ°ΠΊΡΠΎΡΠΎΠ². ΠΡΠΈΠΌΠ΅Ρ ΠΈΡΠΏΠΎΠ»ΡΠ·ΠΎΠ²Π°Π½ΠΈΡ ΡΠΏΠ΅ΡΠΈΡΠΈΡΠ΅ΡΠΊΠΎΠΉ ΡΠΈΠ»ΠΈΠ½Π΄ΡΠΈΡΠ΅ΡΠΊΠΎΠΉ ΡΠ΅ΡΠ²ΡΡΠ½ΠΎΠΉ ΠΏΠ΅ΡΠ΅Π΄Π°ΡΠΈ Π² ΡΠΎΠΎΡΠ²Π΅ΡΡΡΠ²ΠΈΠΈ ΡΠΎ ΡΡΠ°Π½Π΄Π°ΡΡΠΎΠΌ ΠΠΈΡΠ°Ρ (GB 10085-1988) ΠΏΠΎΠΊΠ°Π·ΡΠ²Π°Π΅Ρ, ΡΡΠΎ ΡΠ°ΡΠΈΠΎΠ½Π°Π»ΡΠ½ΡΠΉ Π²ΡΠ±ΠΎΡ ΠΏΠ°ΡΠ°ΠΌΠ΅ΡΡΠΎΠ² ΡΡΠΎΠΉ ΠΏΠ΅ΡΠ΅Π΄Π°ΡΠΈ ΠΌΠΎΠΆΠ΅Ρ ΡΠ²Π΅Π»ΠΈΡΠΈΡΡ Π»ΠΈΠ½ΠΈΡ ΠΊΠΎΠ½ΡΠ°ΠΊΡΠ°, Π° ΡΠ°ΠΊΠΆΠ΅ ΡΠ°ΡΡΠΈΡΠΈΡΡ ΡΠ°Π±ΠΎΡΠΈΠΉ Π΄ΠΈΠ°ΠΏΠ°Π·ΠΎΠ½ Π΅Π΅ Π·ΡΠ±ΡΠ°ΡΠΎΠΉ ΠΏΠΎΠ²Π΅ΡΡ
Π½ΠΎΡΡΠΈ ΠΈ/ΠΈΠ»ΠΈ ΠΎΠ±Π΅ΡΠΏΠ΅ΡΠΈΡΡ Π±ΠΎΠ»Π΅Π΅ ΡΠ°Π²Π½ΠΎΠΌΠ΅ΡΠ½ΡΠΉ ΠΊΠΎΠ½ΡΠ°ΠΊΡ ΠΏΠΎ ΡΠ΅ΡΠ²ΡΡΠ½ΠΎΠΌΡ ΠΊΠΎΠ»Π΅ΡΡ, ΠΏΠΎΠ²ΡΡΠ°Ρ ΡΠ΅ΠΌ ΡΠ°ΠΌΡΠΌ ΡΡΡΠ΅ΠΊΡΠΈΠ²Π½ΠΎΡΡΡ Π»ΠΎΠΊΠ°Π»ΡΠ½ΠΎΠ³ΠΎ Π·Π°ΡΠ΅ΠΏΠ»Π΅Π½ΠΈΡ
Thermo-elasticity for anisotropic media in higher dimensions
In this note we develop tools to study the Cauchy problem for the system of
thermo-elasticity in higher dimensions. The theory is developed for general
homogeneous anisotropic media under non-degeneracy conditions.
For degenerate cases a method of treatment is sketched and for the cases of
cubic media and hexagonal media detailed studies are provided.Comment: 33 pages, 5 figure
Contact angle measurement of free-standing square-millimeter single-layer graphene
Supramolecular & Biomaterials Chemistr
Graphene-stablized lipid monolayer heterostructures: a novel biomembrane superstructure
Supramolecular & Biomaterials Chemistr
Genome-wide association study for flour color-related traits and polyphenol oxidase activity in common wheat
This study aimed to clarify the genetic mechanisms behind wheat flour color. Flour colorrelated traits (L*, a*, and b*) and polyphenol oxidase (PPO) activity are important parameters that influence the end-use quality of wheat. Dissecting the genetic bases and exploring important chromosomal loci of these traits are extremely important for improving wheat quality. The diverse panel of 205 elite wheat varieties (lines) was genotyped using a highdensity Illumina iSelect 90K single-nucleotide polymorphisms (SNPs) assay to disclose the genetic mechanism of flour color-related traits and PPO activity. In 2 different environments and their mean values (MV), 28, 30, 24, and 12 marker-trait associations (MTAs) were identified for L*, a*, b* traits, and PPO activity, respectively. A single locus could explain from 5.52% to 20.01% of the phenotypic variation for all analyzed traits. Among them, 5 highly significant SNPs (P β€ 0.0001), 11 stable SNPs (detected in all environments) and 25 multitrait MTAs were identified. Especially, BS00000020_51 showed pleiotropic effects on L*, a*, and b*, and was detected in all environments with the highest phenotypic contribution rates. Furthermore, this SNP was also found to be co-associated with wheat grain hardness, ash content, and pasting temperature of starch in previous studies. The identification of these significantly associated SNPs is helpful in revealing the genetic mechanisms of wheat colorrelated traits, and also provides a reference for follow-up molecular marker-assisted selection in wheat breeding
Sensing at the surface of graphene field-effect transistors
Supramolecular & Biomaterials Chemistr
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