Growth characteristics of agrowaste‐immobilised lactobacilli in soymilk during refrigerated storage

We aimed at evaluating agricultural wastes as solid supports for the immobilisation of lactobacilli in a liquid media, namely soymilk. Lactobacillus acidophilus FTDC 1331, L. acidophilus FTDC 2631, L. acidophilus FTDC 2333, L. acidophilus FTDC 1733 and L. bulgaricus FTCC 0411 were immobilised on solid supports produced from durian (Durio zibethinus), cempedak (Artocarpus champeden) and mangosteen (Garcinia mangostana). The immobilised cells were inoculated into soymilk and stored at 4 °C over 168 h. Soymilk inoculated with non‐immobilised cells was used as the control. Immobilised cells showed higher survivability over 168 h compared to the control, accompanied by higher reduction of simple sugars and oligosaccharides in soymilk. Higher growth and higher utilisation of substrates also led to the higher production of lactic and acetic acids, which lowered the pH in soymilk compared to the control. Our results illustrated that agrowastes could be used as immobilisers to enhance the growth of lactobacilli in a liquid medium.     

Leakage mitigation in NW FET using negative Schottky junction drain and its process variation analysis

Journal of Computational Electronics - In this work, a Schottky junction on the drain side employing low workfunction (WF) metal is proposed as a method to suppress the OFF-state leakage in...     

New simple transistor realizations of second- generation voltage conveyor

In this paper, two new complementary metal oxide semiconductor (CMOS) realizations for second-generation voltage conveyor (VCII) are presented. The first proposed VCII has a very simple structure employing only six transistors. The second proposed VCII employs 11 transistors, and none of the transistors at both proposed circuits suffer from the body effect. Small-signal analysis, parasitic elements, and input-referred noise of the proposed VCIIs are given. Moreover, a new active element called voltage controlled second-generation voltage conveyor (VC-VCII) is proposed as dual element of current controlled second-generation current conveyor (CCCII) active element. Its parasitic resistance at the Y terminal can be controlled electronically. Two presented CMOS structures of VCII are worked as VC-VCII with slight modification. Proposed circuits are simulated in Cadence Analog environment using TSMC 0.18-μm process parameters with ±0.9-V supply voltages. Both CMOS structures occupy a small chip area of 276.8 and 271 μm², respectively. The bandwidth of the current follower stage of the proposed VCIIs is found as 794 MHz, whereas the bandwidth of the voltage follower stage for the first and second proposed VCIIs is found as 2.57 and 1.92 GHz, respectively. As an application example, voltage-mode first-order low-pass filter has been given with its tunable gain by using VC-VCII.     

Rotational molding cycle time reduction through surface‐enhanced molds,Part B: Experimental study

Rotational molding is a process used to manufacture hollow plastic products, and has been heralded as a molding method with great potential. Because of long production cycle times, which are limited by the time required to heat‐up and cool‐down the mold and the product, its productivity is hampered. To address this issue, exterior mold modification techniques (i.e. the application of extended and rough surfaces) have been employed to enhance heat transfer to and from molds, ultimately reducing cycle times. Extended surfaces have the potential to enhance heat transfer by increasing the surface area. Roughness elements are utilized in conjunction with turbulent flows, also producing significant increases in heat transfer rates. Experimental results presented here demonstrate very significant cycle time reductions through the use of surface‐enhanced molds. The experimental savings are in the order of 18 and 28%, whereas the predicted cycle time reductions are around of 21 and 32% for roughness‐enhanced and pin‐enhanced molds, respectively. Although the prediction methods have been unable to forecast the exact experimental cycle times very accurately, they have proved to be useful for predicting the approximate cycle time reductions and the relative rankings of the plain and the surface‐enhanced molds. POLYM. ENG. SCI., 47:1420–1429, 2007. © 2007 Society of Plastics Engineers     

Enzyme Processing of Soy Flour with Minimized Protein Loss

The enzymatic treatment of defatted soy flour (SF) to reduce indigestible carbohydrates can result in undesirable protein loss. Here protein loss was minimized with quantitation of the effects of ionic strength (IS), protease activity, and SF toasting. At the enzyme processing condition (25% w/v SF, 50 °C, pH 4.8, 48 hours), protein loss increased linearly with the IS in enzyme broths (EB); e.g., contacting untoasted SF with water or heat-deactivated EB showed protein loss of 28% in water but up to 40% when IS was increased in the range of 0.04–0.19 M. Protein loss also increased with protease in EB (nondeactivated): after adjusted for IS-related loss, approximately 10% and 25% additional protein loss occurred in EB of 73 and 490–557 U/(g SF) protease, respectively. SDS-PAGE results showed that proteolysis was not extensive, mainly on β-conglycinin α'/α and glycinin acidic 37-kDa subunits; and most of the proteolytic products could be recovered by heat-induced precipitation. SF toasting effects were studied, particularly at 2-hours 160°C, with material balances, protein distributions, and monosaccharide yields in hydrolysates. Overall, protein loss was minimized to 5.2% and the conversion of carbohydrate to monomeric sugars increased to 89.2%.     

Crashworthiness characteristics of natural ramie/bio-epoxy composite tubes for energy absorption application

Using metallic materials in automotive structures increases weight, fuel consumption and cost, therefore, certain trends have begun to use lightweight and cheaper materials. Fibre composites are used in automotive applications because they are stiff, lightweight and stronger than bulk material, as well as they have a comparable energy-absorbing capacity to that of metallic materials. The aim of this study is to investigate the potentials in natural ramie/bio-epoxy composite in crash energy absorption applications. Cubic specimens consisted of 12, 24 and 30 plies of ramie/bio-epoxy laminates with 50, 80 and 120 mm long which were prepared by hand layup method. Static axial compression load was then applied and the energy-absorbing capability of the ramie/epoxy composite was evaluated. The crashworthiness characteristics of the composite tubes were evaluated by measuring the average and peak crushing load, specific energy absorption, total absorbed energy and crush force efficiency in quasi-static axial compression. The failure mode and behaviour of the tubes were investigated by taking photographs and recording the load–displacement curves during the test accomplishment. The test results indicated that natural ramie/bio-epoxy composite tube has the great potential to be used as an effective energy-absorbing device.     

Polylactide‐perylene derivative for blue biodegradable organic light‐emitting diodes

In this work we demonstrate, for the first time, the use of polylactic acid (PLA) as a biodegradable host matrix for the construction of the active emissive layer of organic light‐emitting diode (OLED) devices for potential use in bioelectronics. In this preliminary study, we report a robust synthesis of two fluorescent PLA derivatives, pyrene‐PLA ( AH10 ) and perylene‐PLA ( AH11 ). These materials were prepared by the ring opening polymerisation of l ‐lactide with hydroxyalkyl‐pyrene and hydroxyalkyl‐perylene derivatives using 1,8‐diazabicyclo[5.4.0]undec‐7‐ene as catalyst. OLEDs were fabricated from these materials using a simple device architecture involving a solution‐processed single‐emitting layer in the configuration ITO/PEDOT:PSS/PVK:OXD‐7 (35%): AH10 or AH11 (20%)/TPBi/LiF/Al (ITO, indium tin oxide; PEDOT:PSS, poly(3,4‐ethylenedioxythiophene) doped with poly(styrenesulfonic acid); PVK, poly(vinylcarbazole); OXD‐7, (1,3‐phenylene)‐bis‐[5‐(4‐tert‐butylphenyl)‐1,3,4‐oxadiazole]; TPBi, 2,2′,2″‐(1,3,5‐benzenetriyl)tris(1‐phenyl‐1H‐benzimidazole)). The turn‐on voltage for the perylene OLED at 10 cd m^–2 was around 6 V with a maximum brightness of 1200 cd m^–2 at 13 V. The corresponding external quantum efficiency and device current efficiency were 1.5% and 2.8 cd A^–1 respectively. In summary, this study provides proof of principle that OLEDs can be constructed from PLA, a readily available and renewable bio‐source. © 2020 The Authors. Polymer International published by John Wiley & Sons Ltd on behalf of Society of Industrial Chemistry.