Palm oil deodorizer distillate as toughening agent in polylactide packaging films

Polylactide (PLA) is the most used biodegradable and biobased food packaging polymer for rigid containers and films. However, its low ductility is a hurdle for increasing its applications in flexible food packaging. A solution is the use of additives. Palm oil deodorizer distillate (PODC) is revealed to be an excellent additive promoting PLA ductility. PODC is a by‐product of vegetable oil refining, which is available in stable quality and in sufficient amounts. Amorphous PLA/PODC blends had an elongation at break of around 130% and that of semi‐crystalline blends was still around 55% compared to the initial 5% of neat PLA. At the same time the PLA rigidity and high glass transition temperatures were kept. PODC was also a very efficient processing aid, allowing for film blow extrusion. The blends were stable in properties during six months without exudation. They complied with legal norms of Food Contact Materials (EU 10/2011) and induced no sensorial alteration of packed food. Therefore PODC is a very interesting alternative to common plasticizers for the production of flexible PLA packaging films. © 2016 Society of Chemical Industry     

Separation of titanium dioxide from photocatalytically treated water by cross-flow microfiltration

This study focuses on the separation of titanium dioxide from water by cross-flow microfiltration (CMF) within wastewater treatment by photocatalysis using slurry reactor systems. The systematic studies have shown that the separation performance of TiO2 particles is strongly affected by cross-flow velocity, transmembrane pressure, feed concentration, pH of the suspension and ionic strength. An extreme sensitivity to pH and electrolyte concentration indicates the importance of interfacial effects in solid-liquid separation of TiO2 particles. Under optimal conditions, permeate fluxes of up to 1250 l m-2 h-1, approaching those of pure water, could be obtained with a polypropylene membrane which is not sensitive to abrasion. The obtained results makes TiO2 separation by cross-flow microfiltration attractive in solar-catalytic detoxification.     

Experimental and Theoretical Assessment of Multipath Effects on QPSK

Qualitative and quantitative agreement between experimental and theoretical results for binary error probability for a coherent QPSK system degraded by intersymbol interference is given. The source of intersymbol interference is a delayed and attenuated replica of the transmitted signal which may represent several forms of observed multipath. Although the experimental results pertain to a particular 1 Gbit/s modem, the theory is applicable for any data rate.     

A validity study of functionally-based behavioral consultation with students with emotional/behavioral disabilities.

Eighteen students (K-11th grade) with emotional/behavioral disorders who were at-risk for change of placement to more restrictive settings participated. Construct validity of functional behavioral assessment (FBA) was assessed with a multifunction-multimethod matrix that showed excellent convergent and divergent agreement with combined FBA methods and functional analysis results. Treatment validity was assessed with random assignment to either a FBA with consultation condition (FBC) or to a behavioral consultation without FBA condition (BC). Growth curve analysis showed a significant decrease in inappropriate behavior from baseline to treatment for both treatment groups compared to a control group. The efficiency of teachers' implementation effected treatment validity. Effect sizes showed that regardless of treatment condition that interventions with good fidelity realized the largest effect (d = -1.14). Social and habilitative validity was assessed with telephone interviews conducted a year after treatment. Sixty-five percent attributed the students' problem behaviors to their thoughts or feelings, whereas only 25% attributed it to classroom variables. Many (57%) indicated the most helpful intervention would be individual counseling, whereas only 14% indicated a more involved classroom management plan would be useful. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Transient Dynamic Response and Failure of Sandwich Composite Structures under Impact Loading with Fluid Structure Interaction

The objective of this study is to examine the Fluid Structure Interaction (FSI) effect on transient dynamic response and failure of sandwich composite structures under impact loading. The primary sandwich composite used in this study consisted of a 6.35?mm balsa core and a multi-ply symmetrical plain weave 6?oz E-glass skin. Both clamped sandwich composite plates and beams were studied using a uniquely designed vertical drop-weight testing machine. There were three impact conditions on which these experiments focused. The first of these conditions was completely dry (or air surrounded) testing. The second condition was completely water submerged. The final condition was also a water submerged test with air support at the backside of the plates. The tests were conducted sequentially, progressing from a low to high drop height to determine the onset and spread of damage to the sandwich composite when impacted with the test machine. The study showed the FSI effect on sandwich composite structures is very critical such that impact force, strain response, and damage size are generally much greater with FSI under the same impact condition. As a result, damage initiates at much lower impact energy conditions with the effect of FSI. Neglecting to account for FSI effects on sandwich composite structures results in very non-conservative analysis and design. Additionally, it was observed that the damage location changed for sandwich composite beams with the effect of FSI.     

Processing and properties of syntactic foams reinforced with carbon nanotubes

This article presents synthesis and mechanical characterization of carbon nanotube (CNT)‐reinforced syntactic foams. Following a dispersion approach (comprising ultrasonic, calendering, and vacuum centrifugal mixing), single‐ and multi‐walled functionalized CNTs (FCNTs) were incorporated into two foam composites containing various commercially available microballoon grades (S38HS, S60HS, and H50 from 3M). The FCNT‐reinforced composites were tested for compressive strength and apparent shear strength before and after hot/wet conditioning. The results showed that the FCNT‐reinforced composites' mechanical properties depended on the vacuum pressure used during processing. Compared with pristine and commercially available syntactic foam (EC‐3500 from 3M), the FCNT‐reinforced composites processed at high vacuum (0.2 kPa) showed significant increase in compressive strength and apparent shear strength before and after hot/wet conditioning. Dynamic mechanical analysis showed an increase of about 22°C in glass transition temperature for composites processed at high vacuum with 0.5 wt % FCNT and 45 wt % S38HS–5 wt % S60HS microballoons. Thermogravimetric analysis indicated water absorption and lower decomposition temperature for the FCNT‐reinforced composite mixed at atmospheric pressure, whereas no significant change was observed for the compound processed at high vacuum. Fracture analysis showed matrix failure for the composite processed at high vacuum and microballoon crushing for the composite mixed at atmospheric pressure. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012     

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Millimeter-wave propagation in vegetation: experiments and theory

Microwave/millimeter-wave propagation in woods and forests was investigated at 9.6, 28.8, and 57.6 GHz. The experiments were repeated over the same transmission paths, under both summer and winter conditions, i.e. with tree in leaf and without leaves. Of particular interest were the range dependence, beam broadening, and depolarization of millimeter-wave beams in vegetation and frequency dependence of these effects. The experiments have shown, in particular, that the range dependence is characterized by a high attenuation rate at short vegetation depths and a reduced attenuation rate at large depth. For trees fully in leaf, the transition between the two regimes can be abrupt and the change in attenuation rate substantial. Just after the transition significant beam broadening (and depolarization) occurs. A theory of millimeter-wave propagation in vegetation was derived using transport theory