Search Options

Sort by:

Sort search results by

Publication Type:

Publication Type filter

Open access:

Publication Date:

Periodicals:

Periodicals filter

Search results

Online since: January 2018
Authors: Zbyněk Keršner, Hana Šimonová, Libor Topolář, Pavel Rovnaník, Pavel Schmid
Quartz sand with maximum grain size of 2.5 mm was used as aggregate in order to prepare AAS mortar.
GTDiPS software [4] was used to correct the diagrams (elimination of data point duplication and reduction of the number of such points).
Mechanical fracture parameters are accompanied by parameters of AE signals which were recorder until peak load, namely number of AE events NAE, duration of AE signals DAE, amplitude of AE signals AAE and energy of AE signals EAE.
The addition of graphite powder to AAS caused a decrease in the number of AE events detected until peak load.
Online since: October 2015
Authors: Leszek Adam Dobrzański, Wojciech Pakieła, Anna Ewa Tomiczek, Błażej Tomiczek
The tribological analysis reveals that composite materials – irrespective of the measuring cycles number and load – are characterised by much smaller wear volume in comparison to the matrix material.
The MMCs obtained as a result of mechanical alloying, cold compacting and hot extrusion are characterised with the microstructure of homogeneous distribution of halloysite particles in fine-grain matrix of AlMg1SiCu alloy, facilitate the obtainment of higher values of mechanical properties, compared to the base alloy.
Acknowledgements The project was financed by the National Science Centre granted on the basis of the decision number DEC-2011/03/B/ST8/06076.
Online since: May 2022
Authors: Nikolay Ferdinandov, Ivo Draganov
The two models are based on the finite elements method (FEM) and have different complexity and number of participating parameters.
A number of authors consider metallurgical processes.
Robson and Campbell [19] offer a model for recrystallization and grain growth.
[19] Robson J., Campbell L., Model for grain evolution during friction stir welding of aluminium alloys, Science and Technology of Welding and Joining, Vol. 15.
Online since: June 2014
Authors: Zhi Rong Wang, Wei Li Wang, Xiao Yan Zhu, Jing Lan Wang, Zhi Jie Han, Ya Hua
In recent years, a large number of studies about above factors had been launched, where soil texture was considered to be one of the important factors affecting microbial adsorption.
(1) (2) Where qe, qt is the solid microbial concentration of adsorption equilibrium and at time t respectively Table 1 The basic physical and chemical properties of the quartz sands Quartz sand number Soil texture Texture(%) Average grain diameter (μm) Organic matter (%) Available phosphorus (mg/g) Total nitrogen (g/kg) Total salt (g/kg) Clay Silt Sand 1 Sand 0.00 0.00 100.00 351 0.00 8.97 0.0126 0.55 2 Loamy sand 0.22 4.91 94.88 319 0.00 8.99 0.0113 0.53 3 Sandy loam 0.88 20.04 79.17 217 0.00 9.14 0.0074 0.48 4 Loam 1.82 41.23 56.06 71 0.00 9.05 0.0017 0.39 5 Silty sandy loam 1.53 48.17 49.69 27 0.00 9.17 0.0000 0.37 Note: International standard (clay(<0.002mm),Silt(0.02~0.002mm)and Sand(2~0.02mm)) were used to divide the quartz sand particles .
Table 2 Asorption dynamics equation parameters of E. coli Quartz sand number Measured value PFORE PSORE Elorich IDM qe (107cfu/g) R2 k1 qe1 (107cfu/g) δ1(%) R2 h k2 qe2 (107cfu/g) δ2(%) R2 R2 kp 1 54.61 0.9361 0.09 75.74 38.68 0.9959 5.18 0.0017 67.57 23.72 0.9886 0.9480 6.54 2 83.38 0.9074 0.16 102.64 23.10 0.9995 27.62 0.0038 88.50 6.14 0.9535 0.8610 5.24 3 84.88 0.9861 0.15 31.95 -62.35 0.9998 81.30 0.0113 86.96 2.45 0.8775 0.7541 2.61 4 86.24 0.8679 0.15 11.83 -86.28 1.0000 243.90 0.0328 86.96 0.83 0.7879 0.6429 1.13 5 87.02 0.8634 0.14 10.37 -88.09 1.0000 208.33 0.0275 87.72 0.80 0.8520 0.7185 1.21 Note: qe is the measured absorption capacity of quartz, qe1, qe2 is the absorption capacity calculated by PFORE and PSORE respectively, , Table 3 Desorption dynamics equation parameters of E. coli Quartz sand number Measured value  PFORE PSORE Elorich IDM qed (107cfu/g) R2 k1 qe1d (107cfu/g) δ1(%) R2 h k2 qe2d (107cfu/g) δ2(%) R2 R2 kp 1 2.66 0.9968 0.04 1.49 -44.24 0.9996
Indicating that the smaller quartz sands grain size was, the greater the adsorption rate would be, and the adsorption capacity would be larger.
Table 4 Adsorption and desorption isotherm parameters of Henry equation Quartz sand number Adsorption Desorption HI kh R2 kh R2 1 1.9045 0.9999 55.764 0.9990 28.27 2 2.2151 0.9997 118.54 1.0000 52.51 3 13.396 0.9892 225.48 1.0000 15.83 4 35.899 0.9873 390.42 0.9964 9.88 5 49.744 0.9599 616.33 0.9974 11.39 It can be seen from the correlation coefficients (Table 4), the Henry equation is also can be used to describe the desorption processes of E. coli.
Online since: July 2004
Authors: S. Schlabach, V. Szabó, D. Vollath, A. Braun, Rolf Clasen
EXAFS measurements show astonishingly low coordination numbers caused by high concentrations of Schottky defects (Table 1) corresponding perfectly with density values obtained by He-pycnometry (Table 2).
Nano-ZrO2/Al2O3 Coarse ZrO2(Y2O3) Calculated cubic ZrO2 Calculated tetragonal ZrO2 Shell Zr-O Zr-Zr Zr-O Zr-Zr Zr-O Zr-Zr Zr-O Zr-Zr Radial distance ± σ [nm] 0.214 ±0.0076 0.365 ±0.0089 0.219 ±0.0087 0.360 ±0.010 0.2238 0.365 0.207 / 0.245 0.364 / 0.368 Coordination number 4.1 6.4 5.4 10.5 8 12 4 / 4 4 / 8 Table 1.
Radial shell distances and coordination numbers for alumina coated nanosized zirconia particles compared with the data of coarse-grained cubic zirconia and calculated values of the cubic and tetragonal structure [4].
Online since: May 2006
Authors: Henrique Santos, Nuno Lourenço
Results The results obtained in the wear tests are presented in figure 2 and show that the non inserted ductile iron presents a loss of weight (measured by the slope of the curve of the weight loss versus number of wheel revolutions) approximately fifty percent higher than the inserted material.
Fig. 2 - Weight loss versus number of wheel revolutions for non inserted ductile iron (gray triangles), inserted ductile iron in the as-cast state (white balls) and inserted ductile iron with a rectified surface (black balls).
The non inserted ductile iron test piece surface has shown a uniform waviness with a wavelength around half a millimeter, equal to the average diameter of the sand grains, as one may see in see figure 3a); at higher magnification, much finer wear marks have been observed, as presented in figure 3b).
In fact, as presented in previous work [2], the base metal shows a hardness number close to 250 VHN/4.9N, whilst the hardness of the inserted material is in the range from 400 to 500 VHN/4.9N along 2.5 mm; this higher hardness is surely coresponsible for the less intense abrasive action during the wear test.
Online since: February 2011
Authors: An Guo Huang, Wei Huang, Jing Fu Liu, Hu Zhang, Wei Yu, Zhi Yuan Li
Diffusion bonding tests were carried out in a vacuum environment with 1.3 × 10-2Pa.[8,9,10] Table.1 connecting forming processing parameter of three kinds of samples Samples number Upper limit Temp.
The diffusion layer is a multi-phase organization, and layer thickness, which has a great influence on joint strength, augments with the increasing temperature and cycling numbers.
Fracture is of mixed type and dimply pit and cleavage plane exist in the local area, which show that the joint has certain toughness. 25-steel side TC4 side 25-steel side TC4 side Fig.5 fracture morphology of tensile sample At the side of TC4, because of the joint bearing tensile stress and the limited slip system, strain will occur between the lath interface of residual β grain and refinement α phase in the welding seam.
The atomic radius, crystal lattice type, lattice constants and atomic number of the outer electron of Al is close to Fe, which is beneficial for metal connection and helpful to the conduct of diffusion bonding.
Online since: September 2013
Authors: Xiao Yu Li, Tian Cheng Liu, Jing Ouyang, Hua Ming Yang
In fact, the mass of each ball and the number of the balls is determinate due to the same condition of b/r in the experiments.
The mass and the number of balls are ambivalent factors, because if the mass of each ball increases, the number of the balls must decrease.
But, steel slag milled by C ball for 3 h is finer-grained than A ball under the same conditions.
Online since: August 2013
Authors: Jin Bo Song, Xiong Ying Ye
Fig.1 Schematic diagram of overall structure At present, Nanchang traffic problems are: road construction is not perfect 45.7%; peak personnel flow is too large 51.4% bus system is not perfect; 42.8%. 51.4% of the people think the present Nanchang Nanchang city traffic situation is not good, there is the Development Zone City traffic problems: the traffic lights to set remains to be improved in 54.3%. 68.6% some people think that the number of Nanchang city traffic lights on the road too little, some junctions often traffic jam because of lack of traffic lights. 68.6% think that the road ditch is not wide enough too crowded, lane number is too small, the need to expand.
Nanchang as a piece of fruit production base, excellent transport links can make Nanchang fruit the fresh shipped to the field, and also make a single agricultural structure based on grain production to diversify the structure transformation.
Convenient transportation network gave birth to a large number of logistics companies, the goods shipped from all over the city at the remote can be reached in a short period of time.The logistics structure qualitative change.
Online since: March 2010
Authors: Tao Li, Dong Bo Wang, Xiu Tian Yan, Ning Sheng Guo
But the EDP model is hardly predictable and can therefore only be pre-planned on a coarse-grained level, besides there are many design making in the design process [5].
In the knowledge representation, the Michigan code is used and real number instead of binary coding is used for the convenience of EDP domain knowledge.
Table3 computation of fitness function Rule IF A THEN C IF A THEN NOT C IF NOT A THEN C IF NOT A THEN NOT C Number pp pn np nn AO Knowledge Learning Algorithm and Case Study.
The training data set normally is coming from the case history in EDP, and because the real number coding is used, the base vector is used to set the initial chromosome; in certain generation, the fitness is computed for the current population, and part of the chromosome is selected according to specific GAP determine the percentage of selection, the single crossover is used to recombine the sub-population before the sub-population mutation, then a set of new population is added into the sub-population for the next loop, the new rule then can be learned after certain generation.
Showing 21641 to 21650 of 28673 items