Bianchimano AS¹, MG Murray^2,3, ME Aztiria¹, B Montes^2,3, ML Calfuán², MI Prat¹

Phyton-International Journal of Experimental Botany, Vol.83, pp. 9-15, 2014, DOI:10.32604/phyton.2014.83.009

Abstract Chenopodium album is a very polymorphic, cosmopolitan, annual herb that grows spontaneously in modified soils in wasteland in the outlying urban zones of Bahía Blanca. In this city, the flowering period is mainly during February and March, which coincides with the highest concentrations of this pollen type in the atmosphere of the city. The objective of this study was to characterize the pollen grains of Chenopodium album, both morphologically and immunochemically, that were obtained from three different zones in the urban area of Bahía Blanca. Samples were collected from the three separate zones in the city that were far apart.… More >

Rui Yu-kui, Zhang Fu-suo, Shen Jian-bo

Phyton-International Journal of Experimental Botany, Vol.78, pp. 101-104, 2009, DOI:10.32604/phyton.2009.78.101

Abstract Nitrogen fertilization has played a significant role in increasing crop yield, and solving problems of hunger and malnutrition worldwide. However, excessive nitrogen inputs do not significantly increase crop yields but may lead to many serious environmental problems. The effects of nitrogen fertilization rate were studied on heavy metal content of corn grains. Our results show that nitrogen fertilization management is beneficial for reducing production costs, protecting the environment, and improving the quality of farm products. More >

Junbo Wang^*, Leiting Dong

The International Conference on Computational & Experimental Engineering and Sciences, Vol.21, No.4, pp. 75-75, 2019, DOI:10.32604/icces.2019.04820

Abstract In this study, two/three-dimensional computational grains are developed for micromechanical modeling of heterogeneous materials with nanoscale inhomogeneities, considering the interface stress effect. Two types of computational grains are developed, depending on the types of inhomogeneity in each element. Each computational grain can include alternatively a spherical void or a spherical elastic inclusion. In these computational grains, an inter-element compatible displacement field is assumed along the element outer-boundary, and interior displacement fields in the matrix as well as in the inclusion are independently assumed as T-Trefftz trial functions. For planar problems, complex potentials are used to derive the Trefftz trial displacement… More >

Zone-Ching Lin¹, Ming-Long Huang¹

The International Conference on Computational & Experimental Engineering and Sciences, Vol.10, No.3, pp. 89-90, 2009, DOI:10.3970/icces.2009.010.089

Abstract The paper develops a two dimensional quasi-steady molecular staic model to simulate the vertical down press copper workpiece by down press the nanoscale depth of abrasive grains in different shapes. The research of the down pressing copper workpiece of abrasive grains in this paper uses the hexagonal close packed diamond abrasive grains to down press the perfect face-centered cubic copper. The paper's simulation of down pressing nanoscale depth model of abrasive grain by two dimensional quasi-steady molecular statics model is a step by step to down press copper workpiece by diamond abrasive grain. It is assumed that each atom of… More >

Z. T. Ma¹, X. Zhang^1,2, P. Huang¹

CMES-Computer Modeling in Engineering & Sciences, Vol.55, No.1, pp. 61-88, 2010, DOI:10.3970/cmes.2010.055.061

Abstract The Material Point Method (MPM) is more expensive in terms of storage than other methods, as MPM makes use of both mesh and particle data. Therefore, it is critical to develop an efficient MPM framework for engineering applications, such as impact and explosive simulations. This paper presents a new architecture for MPM computer code, developed using object-oriented design, which enables MPM analysis of a mass of grains, large deformation, high strain rates and complex material behavior. It is flexible, extendible, and easily modified for a variety of MPM analysis procedures. An MPM scheme combining contact algorithm with USF, USL and… More >

Xiangkui Zhou¹, Kai Wang¹, Zhifeng Xu¹, Qiang Wang², Guojian Li^1,, Jicheng He^1,

CMC-Computers, Materials & Continua, Vol.41, No.2, pp. 153-162, 2014, DOI:10.3970/cmc.2014.041.153

Abstract At present, the functionally gradient cemented carbide (FGCC) substrate with enrich cobalt on surface is mainly formed from medium grained WC grains. In order to further improve the properties of gradient cemented carbides, the ultrafine powder was chosen in this study and the functionally gradient cemented carbide with ultrafine grains was prepared by a two-step process, where the cemented carbide is first lower pressure pre-sintered and then subjected to a gradient sintering. The results show that it is possible to form gradient layer with enriched cobalt on surface by this method and also the grain growth can be inhibited by… More >

Leiting Dong^1,2, Salah H. Gamal³, Satya N. Atluri^2,4

CMC-Computers, Materials & Continua, Vol.37, No.1, pp. 1-21, 2013, DOI:10.3970/cmc.2013.037.001

Abstract In this paper, a simple and reliable procedure of stochastic computation is combined with the highly accurate and efficient Trefftz Computational Grains (TCG), for a direct numerical simulation (DNS) of heterogeneous materials with microscopic randomness. Material properties of each material phase, and geometrical properties such as particles sizes and distribution, are considered to be stochastic with either a uniform or normal probabilistic distributions. The objective here is to determine how this microscopic randomness propagates to the macroscopic scale, and affects the stochastic characteristics of macroscopic material properties. Four steps are included in this procedure: (1) using the Latin hypercube sampling,… More >