Evaluating the Influence of Specific Mechanical Energy on Biopolymer Blends Prepared via High-Speed Reactive Extrusion

2019 ◽  
Vol 1 (6) ◽  
pp. 1410-1419 ◽  
Author(s):  
Bárbara A. Calderón ◽  
Matthew S. McCaughey ◽  
Conor W. Thompson ◽  
Vincenzo L. Barinelli ◽  
Margaret J. Sobkowicz
Keyword(s):  
High Speed ◽  
Mechanical Energy ◽  
Reactive Extrusion ◽  
Specific Mechanical Energy ◽  
Biopolymer Blends

In-line Measurement of the Viscous Behaviour of Wheat Starch During Extrusion. Application to Starch Cationisation

2007 ◽  
Vol 17 (2) ◽  
pp. 21222-1-21222-7 ◽  
Author(s):  
F. Berzin ◽  
A. Tara ◽  
L. Tighzert
Keyword(s):  
Water Content ◽  
Mechanical Energy ◽  
Processing Condition ◽  
Reactive Extrusion ◽  
Wheat Starch ◽  
Line Measurement ◽  
Specific Mechanical Energy ◽  
Slit Die ◽  
Viscous Behaviour ◽  
Temperature Water

Abstract A specific twin channel slit die was used to measure in-line the viscous behaviour of an extruded wheat starch. This allows to put in evidence the influences of temperature, water content and specific mechanical energy (SME). The proposed rheological law permits to satisfactorily predict the viscosity of a wheat starch for any processing condition. Original results are presented for the behaviour of cationic starches obtained by reactive extrusion.

scholarly journals Physicochemical and Sensorial Evaluation of Meat Analogues Produced from Dry-Fractionated Pea and Oat Proteins

Foods ◽  
2020 ◽  
Vol 9 (12) ◽  
pp. 1754
Author(s):  
Davide De Angelis ◽  
Aleksei Kaleda ◽  
Antonella Pasqualone ◽  
Helen Vaikma ◽  
Martti Tamm ◽  
...  
Keyword(s):  
Soy Protein ◽  
Mechanical Energy ◽  
Absorption Capacity ◽  
Process Conditions ◽  
Oil Absorption ◽  
Water Absorption Capacity ◽  
Protein Isolates ◽  
Pea Protein ◽  
Specific Mechanical Energy ◽  
Sensorial Evaluation

Pea protein dry-fractionated (PDF), pea protein isolated (PIs), soy protein isolated (SIs) and oat protein (OP) were combined in four mixes (PDF_OP, PIs_OP, PDF_PIs_OP, SIs_OP) and extruded to produce meat analogues. The ingredients strongly influenced the process conditions and the use of PDF required higher specific mechanical energy and screw speed to create fibrous texture compared to PIs and SIs. PDF can be conveniently used to produce meat analogues with a protein content of 55 g 100 g−1, which is exploitable in meat-alternatives formulation. PDF-based meat analogues showed lower hardness (13.55–18.33 N) than those produced from PIs and SIs (nearly 27 N), probably due to a more porous structure given by the natural presence of carbohydrates in the dry-fractionated ingredient. PDF_OP and PIs_PDF_OP showed a significantly lower water absorption capacity than PIs OP and SIs_OP, whereas pea-based extrudates showed high oil absorption capacity, which could be convenient to facilitate the inclusion of oil and fat in the final formulation. The sensory evaluation highlighted an intense odor and taste profile of PDF_OP, whereas the extrudates produced by protein isolates had more neutral sensory characteristics. Overall, the use of dry-fractionated protein supports the strategies to efficiently produce clean-labeled and sustainable plant-based meat analogues.

scholarly journals Effect of exchange reactions and free radical grafting on the high‐speed reactive extrusion of poly(butylene succinate) and poly(propylene carbonate) blends

2019 ◽  
Vol 59 (10) ◽  
pp. 1986-1998
Author(s):  
Bárbara A. Calderón ◽  
Conor W. Thompson ◽  
Vincenzo L. Barinelli ◽  
Matthew S. McCaughey ◽  
Margaret J. Sobkowicz
Keyword(s):  
Free Radical ◽  
Propylene Carbonate ◽  
High Speed ◽  
Reactive Extrusion ◽  
Exchange Reactions ◽  
Butylene Succinate ◽  
Poly Propylene

Factors Contributing to Maximum Height of Dives after Takeoff from the 3M Springboard

1988 ◽  
Vol 4 (3) ◽  
pp. 231-259 ◽  
Author(s):  
Ross H. Sanders ◽  
Barry D. Wilson
Keyword(s):  
Vertical Velocity ◽  
Kinetic Data ◽  
High Speed ◽  
Mechanical Energy ◽  
Center Of Gravity ◽  
Whole Body ◽  
Maximum Height ◽  
Body Angle ◽  
High Speed Cinematography ◽  
Hip Flexion

This study investigated factors contributing to the maximum height achieved by divers after takeoff from the 3m springboard. Twelve elite male divers and 12 elite female divers competing in the 1986 Australian National Championships were filmed using high-speed cinematography. Kinematic and kinetic data for the takeoff phase were derived from the digitized film. Variables analyzed included center of gravity (CG) displacement and velocity, the acceleration of the CG relative to the springboard, and the components of mechanical energy contributing to height achieved by the diver’s CG. Body orientation was described in terms of the angles at the hip, knee, and ankle, and whole body angle of lean. Comparison of timing differences among dive groups and divers was aided by normalizing the data with respect to time. It was found that the height achieved was highly dependent on the rotational requirements of the dive, with males achieving greater heights than females. Divers who achieve good height compared to other divers performing the same dive are characterized by a large vertical velocity at touchdown from the hurdle and a minimization of hip flexion (forward dives) and knee flextion (reverse dives) at takeoff.

scholarly journals The Cross-Bridge Spring: Can Cool Muscles Store Elastic Energy?

Science ◽  
2013 ◽  
Vol 340 (6137) ◽  
pp. 1217-1220 ◽  
Author(s):  
N. T. George ◽  
T. C. Irving ◽  
C. D. Williams ◽  
T. L. Daniel
Keyword(s):  
Energy Storage ◽  
Elastic Energy ◽  
Molecular Motors ◽  
High Speed ◽  
Mechanical Energy ◽  
Elastic Strain Energy ◽  
Time Resolved ◽  
X Ray ◽  
Cross Bridge ◽  
Cross Bridges

Muscles not only generate force. They may act as springs, providing energy storage to drive locomotion. Although extensible myofilaments are implicated as sites of energy storage, we show that intramuscular temperature gradients may enable molecular motors (cross-bridges) to store elastic strain energy. By using time-resolved small-angle x-ray diffraction paired with in situ measurements of mechanical energy exchange in flight muscles of Manduca sexta, we produced high-speed movies of x-ray equatorial reflections, indicating cross-bridge association with myofilaments. A temperature gradient within the flight muscle leads to lower cross-bridge cycling in the cooler regions. Those cross-bridges could elastically return energy at the extrema of muscle lengthening and shortening, helping drive cyclic wing motions. These results suggest that cross-bridges can perform functions other than contraction, acting as molecular links for elastic energy storage.

Structural and Rotordynamic Force Coefficients of a Shimmed Bump Foil Bearing: An Assessment of a Simple Engineering Practice

2015 ◽  
Vol 138 (1) ◽  
Author(s):  
Luis San Andrés ◽  
Joshua Norsworthy
Keyword(s):  
Loss Factor ◽  
High Speed ◽  
Static Load ◽  
Low Cost ◽  
Mechanical Energy ◽  
Excitation Frequency ◽  
Engineering Practice ◽  
Force Coefficients ◽  
Damping Coefficients ◽  
Stiffness And Damping

High speed rotors supported on bump-type foil bearings (BFBs) often suffer from large subsynchronous whirl motions. Mechanically preloading BFBs through shimming is a common, low cost practice that shows improvements in rotordynamic stability. However, there is an absence of empirical information related to the force coefficients (structural and rotordynamic) of shimmed BFBs. This paper details a concerted study toward assessing the effect of shimming on a first generation BFB (L = 38.1 mm and D = 36.5 mm). Three metal shims, 120 deg apart, are glued to the inner surface of the bearing cartridge and facing the underside of the bump foil strip. The shim sets are of identical thickness, either 30 μm or 50 μm. In static load tests, a bearing with shims shows a (nonlinear) structural stiffness larger than for the bearing without shims. Torque measurements during shaft acceleration also demonstrate a shimmed BFB has a larger friction coefficient. For a static load of 14.3 kPa, dynamic loads with a frequency sweep from 250 Hz to 450 Hz are exerted on the BFB, without and with shims, to estimate its rotordynamic force coefficients while operating at ∼50 krpm (833 Hz). Similar measurements are conducted without shaft rotation. Results are presented for the original BFB (without shims) and the two shimmed BFB configurations. The direct stiffnesses of the BFB, shimmed or not, increase with excitation frequency, thus evidencing a mild hardening effect. The BFB stiffness and damping coefficients decrease slightly for operation with rotor speed as opposed to the coefficients when the shaft is stationary. For frequencies above 300 Hz, the direct damping coefficients of the BFB with 50 μm thick shims are ∼30% larger than the coefficients of the original bearing. The bearing structural loss factor, a measure of its ability to dissipate mechanical energy, is derived from the direct stiffness and damping coefficients. The BFB with 50 μm thick shims has a 25% larger loss factor—average from test data collected at 300 Hz to 400 Hz—than the original BFB. Further measurements of rotor motions while the shaft accelerates to ∼50 krpm demonstrate the shimmed BFB (thickest shim set) effectively removes subsynchronous whirl motions amplitudes that were conspicuous when operating with the original bearing.

A Kind of Active Control Damping Shock Absorber

2014 ◽  
Vol 620 ◽  
pp. 511-515
Author(s):  
Han Song Yang ◽  
Peng Li ◽  
Li Zhi Gu ◽  
Hui Juan Guo
Keyword(s):  
Active Control ◽  
High Speed ◽  
Shock Absorber ◽  
Mechanical Energy ◽  
Control Variable ◽  
Suspension System ◽  
High Speed Train ◽  
Proportional Valve ◽  
The Road ◽  
Variable Damping

It is the main decrease press type used in high speed train of semi suspension system, as the parameter can not be regulated freely of the semi suspension system, to design a kind of damping shock absorber which with the sensitive and soft system are very important, this system which using of the Electro hydraulic proportional valve to regulation the safety valve, the guide valve and the damping force of shock absorber, get the recycle method of the hydraulic system from inner to outside, and also using the suspension active control variable damping shock absorber to detect the road, this device, in fact, by vibration, which let the valve move relation, turn the mechanical energy into hot and release outside, thus decrease the vibration. To design this variable damping shock absorber ,compared with the semi suspension system ,for it has the connect system and Electro hydraulic proportional valve, and with the road detectors, and various variable parameters, Which let the high speed train more stable and safety, overcome the short of parameter regulation for the semi-automatic suspension system.

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