Effects of ultrasound on cross-flow ultrafiltration of skim milk: Characterization from macro-scale to nano-scale

2014 ◽  
Vol 470 ◽  
pp. 205-218 ◽  
Author(s):  
Y. Jin ◽  
N. Hengl ◽  
S. Baup ◽  
F. Pignon ◽  
N. Gondrexon ◽  
...  
Keyword(s):  
Author(s):  
Angel G. Perez ◽  
Julie S. Linsey

There are countless products that perform the same function but are engineered to suit a different scale. Designers are often faced with the problem of taking a solution at one scale and mapping it to another. This frequently happens with design-by-analogy and bioinspired design. Despite various scaling laws for specific systems, there are no global principles for scaling systems, for example from a biological nano-scale to macro-scale. This is likely one of the reasons bioinspired design is difficult. Very often scaling laws assume the same physical principles are being used, but this study of products indicates that a variety of changes occur as scale changes, including changing the physical principles to meet a particular function. Empirical product research was used to determine a set of principles by observing and understanding numerous products to unearth new generalizations. The function a product performs is examined in various scales to view subtle and blatant differences. Principles are then determined. This study provides an initial step in creating new innovative designs based on existing solutions in nature or other products that occur at very different scales. Much further work is needed by studying additional products and bioinspired examples.


2019 ◽  
Vol 956 ◽  
pp. 332-341 ◽  
Author(s):  
Jia Fu

The performance prediction of C-S-H gel is critical to the theoretical research of cement-based materials. In the light of recent computational material technology, modeling from nano-scale to micro-scale to predict mechanical properties of structure has become research hotspots. This paper aims to find the inter-linkages between the monolithic "glouble" C-S-H at nano-scale and the low/high density C-S-H at the micro-scale by step to step method, and to find a reliable experimental verification method. Above all, the basic structure of tobermorite and the "glouble" C-S-H model at nano-scale are discussed. At this scale, a "glouble" C-S-H structure of about 5.5 nm3 was established based on the 11Å tobermorite crystal, and the elastic modulus ​​of the isotropic "glouble" is obtained by simulation. Besides, by considering the effect of porosity on the low/high density of the gel morphology, the C-S-H phase at micro-scale can be reversely characterized by the "glouble". By setting different porosities and using Self-Consistent and Mori-Tanaka schemes, elastic moduli of the low density and high density C-S-H ​​from that of "glouble" are predicted, which are used to compare with the experimental values of the outer and inner C-S-H. Moreover, the nanoindentation simulation is carried out, where the simulated P-h curve is in good agreement with the accurate experimental curve in nanoindentation experiment by the regional indentation technique(RET), thus the rationality of the "glouble" structure modeled is verified and the feasibility of Jennings model is proved. Finally, the studies from the obtained ideal "glouble" model to the C-S-H phase performance has realized the mechanical properties prediction of the C-S-H structure from nano-scale to micro-scale, which has great theoretical significance for the C-S-H structural strengthening research.


2003 ◽  
Vol 38 (7) ◽  
pp. 1549-1560 ◽  
Author(s):  
Darko M. Krstic ◽  
Miodrag N. Tekic ◽  
Marijana D. Caric ◽  
Spasenija D. Milanovic
Keyword(s):  

1997 ◽  
Vol 7 (12) ◽  
pp. 849-861 ◽  
Author(s):  
A. Guerra ◽  
G. Jonsson ◽  
A. Rasmussen ◽  
E. Waagner Nielsen ◽  
D. Edelsten

Author(s):  
Polina Prokopovich ◽  
Stephanos Theodossiades ◽  
Homer Rahnejat ◽  
Darren Hodson

In many drug dispensing devices, such as syringes and inhalers, a rubber ring is used as a seal. During device actuation the seal is subjected to friction which in turn causes it to deform. This can lead to suboptimal performance of the device and as a consequence variability in the delivered dose. Seal friction is complex, arising from adhesion of rubber in contact with a moving counterface, viscous action of a thin film of entrained fluid into the contact and ploughing of seal asperities. Therefore, the first step in the understanding of the conjunctional behaviour of rubber seals is the fundamental study of these friction mechanisms. A developed model can then be validated against measurements, prior to its use in a multi-body dynamic model of the inhaler valve to predict product performance, robustness and variability due to manufacturing tolerances. This paper undertakes two distinct studies. Firstly, a friction model for the rough elastomeric material, typically used for valve seals is developed. The model is then validated against measurements in nano-scale. Friction data is presented for nitrile rubber, using a silicon nitride AFM tip for nano-scale interactions. The validation is then extended to macro-scale motion of an instrumented trolley, incorporating an elastomeric surface sliding on a polymeric counterface. These tests are carried out for polybutylene terephthalate (PBT). Secondly, the validated friction model is used in an elastomeric seal model in-situ within the valve and in contact with a polymeric stem surface and subject to both global fittment deformation and canister pressure. Reasonable agreement is found between the measurements and model predictions for the nano-scale coefficient of friction of rubber against silicon nitride. Similarly, good agreement has been obtained for the mean coefficient of friction of rubber against PBT. In addition, the mechanism of adhesion between contacting surfaces of gasket and stem is taken into account.


Soft Matter ◽  
2018 ◽  
Vol 14 (26) ◽  
pp. 5420-5427 ◽  
Author(s):  
Fereshteh Samadi Taheri ◽  
Hossein Fazli ◽  
Masao Doi ◽  
Mehdi Habibi

Macro-scale experiment and nano-scale simulation of a chain/polymer show the same escape behavior through the pore in the wall in the presence of particles.


2022 ◽  
Vol 2150 (1) ◽  
pp. 012004
Author(s):  
S A Isaev ◽  
A I Leontiev ◽  
D V Nikushchenko ◽  
D Kong ◽  
K M Chung ◽  
...  

Abstract An energy-efficient flat surface is formed when applying single-row cross-flow zigzag grooves (VVVVVV) in a dense arrangement. Convective heat transfer is considered in turbulent flow around a longitudinal fragment of a plate with a length of 40 and a width of 4 with a package of 14 singlerow inclined backslash(\)-shaped grooves with symmetry conditions at the lateral boundaries. The width of the grooves is 1, the depth is 0.25, the edge rounding radius is 0.2, the angles of inclination are 30°, 45°, 50° and 60°, the pitch is 2.4, the Reynolds number is 104, and the thickness of the incoming boundary layer is 0.175. The phenomenon of anomalous enhancement of the separation flow and heat transfer in zigzag grooves and acceleration of the wall flow discovered in inclined oval-trench dimples has been confirmed.


2021 ◽  
Vol 8 ◽  
Author(s):  
Shijun Wang ◽  
Amardeep Singh ◽  
Qiong Liu

Adding conductive materials to cement-based composites can lead to pressure-sensitive properties. In this study, different scales of conductive materials were incorporated, including macro-scale steel fibers, micro-scale carbon black powder, and nano-scale graphene. The coupling effect of three scales of materials ensured that the intelligent concrete had improved strength, lower cost, and comparable pressure-sensitive performance. The results show that the strength of intelligent concrete with multi-scale conductive materials is higher than that of the contrast group of ordinary concrete and intelligent concrete when adding nano-scale graphene alone. Especially, the addition of steel fibers significantly improved the crack resistance of the intelligent concrete. In the elastic stage, the resistivity of intelligent concrete of multi-scale conductive materials decreases with the increase in compression, and the decrease range of resistivity is approximately proportional to the external force. After reaching the peak load, the resistivity of the intelligent concrete gradually increases and can illustrate the damage evolution. This study lays a foundation for the application of intelligent concrete in deformation and damage monitoring.


2009 ◽  
Vol 15 (S3) ◽  
pp. 77-78 ◽  
Author(s):  
A. Pelaez-Vargas ◽  
N. Ferrell ◽  
M. H. Fernandes ◽  
D. Hansford ◽  
F. J. Monteiro

AbstractFrom a biomaterials perspective, it is now understood that success in the osseointegration of a dental implant is conditioned by its “macro”, “micro” and “nano” scale features. Macro-scale roughness is necessary to improve primary stabilization in the post-surgical phase inducing a peri-implant thin fibrous layer. However, the more complex process in the true cell-material interaction is dependent on micro and nano scale phenomena. There is clear evidence that cell adhesion, proliferation, organization and phenotype are modulated at the micro-scale and that protein absorption is fundamentally a process conditioned at nano-scale.


Sign in / Sign up

Export Citation Format

Share Document