Reversed signal propagation BDD based low‐power pass‐transistor logic synthesis

Binary decision diagrams (BDDs) are the most frequently used data structure for the representation and manipulation of Boolean functions in the area of Very Large Scale Integration (VLSI) CAD. In this paper, we propose the reversed‐signal‐propagation (RSP) BDD‐based low‐power pass‐transistor logic (PTL) synthesis. In RSP BDD, the signal flow direction is opposite to that of the forward BDD. So the power supply is taken as a root node and the terminal nodes 0 and 1 represent the function in its normal and complement form. We propose an efficient way to construct the multi‐output function RSP BDD and its PTL realization. Simulation results of the proposed method give lower power consumption and high performance as a result of reduced switching activity than the existing techniques. The power improvement is about 70–80% compared to the existing techniques. © 2013 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc.     

Progress and Prospects of Pyrrole‐Imidazole Polyamide–Fluorophore Conjugates as Sequence‐Selective DNA Probes

Recently, the versatility of N‐methylpyrrole (Py)‐N‐methylimidazole (Im) polyamide conjugates, which have been developed from the DNA‐binding antibiotics distamycin A and netropsin, has been shown. These synthetic small molecules can permeate cells to bind with duplex DNA in a sequence‐specific manner, and hence can influence gene expression in vivo. Accordingly, several reports demonstrating the sequence specificity and biological activity of Py‐Im polyamides have accumulated. However, the benefits of Py‐Im polyamides, in particular those conjugated with fluorophores, has been overlooked. Moreover, clear directions for the employment of these attractive artificial small molecules have not yet been shown. Here, we present a detailed overview of the current and prospective applications of Py‐Im polyamide–fluorophore conjugates, including sequence‐specific recognition with fluorescence emission properties, and their potential roles in biological imaging.     

EFFECT OF DRYING ON FLUIDISATION BEHAVIOUR OF PACKED BEDS OF SHREDDED COCONUT

Drying of shredded coconut is usually carried out commercially in order to facilitate storage over reasonable periods of time and to obtain advantages of reduction of weight and volume in transport and packaging. Fluidised bed drying of materials is generally accepted to be an efficient method of drying. Experiments were carried out to investigate the behaviour of fluidisation of shreddet coconut at various moisture contents. The pressure drop was measured across random packings of shredded coconut. It is seen that shredded coconut does not fluidise easily at moisture contents greater than 0.55 (55 weight percent moisture). It is also seen that fluidisation can be easily achieved by drying shredded coconut to moisture contents between approximately 0.25 to 0.55. The pressure drop characteristics within this region is seen to closely resemble the theoretical behaviour of a fluidised bed. It is also seen that particles of shredded coconut in beds of moisture contents less than 0.25 tend to undergo pneumatic transport if efforts are made to fluidise such beds.     

STUDIES ON STIFLING AND DRYING OF COCOONS FOR LONGER STORAGE

ABSTRACT

Long term storage of stifled cocoons is an important problem during unfavourable seasonal conditions. Cocoons could be stifled within 20 minutes by using steam al 90°C. The shade drying of steam stifled cocoons in thin layers reduced the moisture content from 228 per cent (db) to 3 1.7 per cent (db) within 10 days. By hot air conditioning method the cocoons could be stifled and dried simultaneously. Using hot air at 90°C the cocoons could be stifled within 10 minutes, and dried to the equilibrium moisture content within 2 hours. The cocoons stifled by the hot air conditioning method could be reeled even just after stifling.     

Tolerance limit of chloride for steel in blended cement mortar using the cyclic polarisation technique

The tolerance limit for chloride in ordinary Portland cement (OPC) and blended cements such as Portland pozzolana cement (PPC) and Portland slag cement (PSC) was assessed by cyclic polarisation. This study covers both cement extracts and mortar. The salient features of this investigation were: in extracts, the tolerance limit for chloride actually doubles for PSC when compared to PPC and OPC. The tolerance limit for chloride for various mortars follows the order: PSC > PPC > OPC. In OPC and PPC mortar, the repassivation potential (E _rep) shifted negatively with higher amounts of free chloride but in PSC mortar E _rep shifted positively (+590 mV) even in the presence of 5,000 ppm of free chloride. PSC takes longer time (50 days) to reach E _rep indicating perfect passivity maintained for the embedded steel.     

Optimization of Microwave-Assisted Extraction of Phenolic Antioxidants from Grape Seeds (Vitis vinifera)

Grape seeds (Vitis vinifera) are rich in phytochemicals that have antioxidant properties. The influence of independent variables such as microwave power (100, 150, and 200 W), extraction time (2, 4, and 6 min), and solvent concentration (30%, 45%, and 60% ethanol) and their interactions on total phenols and the antioxidant activity (1,1-diphenyl-2-picrylhydrazyl (DPPH) and ferric ion reducing antioxidant power (FRAP)) were determined; and the microwave-assisted extraction (MAE) process was optimized using a central composite design. The total phenols that were expressed as gallic acid equivalents (GAE), catechin equivalents (CAT), and tannic acid equivalents (TAE) were significantly influenced by the solvent concentration and the time of extraction. A numerical optimization was carried out to obtain the overall conditions for MAE of phenolic antioxidants from grape seed. The response variables were maximized for 6 min of MAE of grape seed (GS) with 32.6% ethanol at 121 W with a desirability function of 0.947. The predicted extraction yields were 13?±?0.89, 21.6?±?1.59, and 15.9?±?1.32 mg GAE, CAT, and TAE, respectively per gram of GS. The predicted antioxidant activity per gram of dry weight GS was 80.9% for the inhibition of DPPH and 135 μM ascorbic acid equivalents for FRAP test. The predicted response values were significantly correlated with the observed ones as follows: GAE r?=?0.995, CAT r?=?0.990, TAE r?=?0.996, DPPH r?=?0.996, and FRAP r?=?0.996.     

Innovative multi‐processed N‐doped carbon and Fe3O4 cathode for enhanced bioelectro‐Fenton microbial fuel cell performance

A novel bioelectro‐Fenton microbial fuel cell (BEF‐MFC) cathode has been fabricated by modification of electrode using multi‐processing of nitrogen‐doped carbon (NDC)/nano‐Fe₃O₄ method with the aims of cost‐effectiveness, high oxygen reduction reaction (ORR) efficiency, and power performance enhancement. In this study, BEF‐MFC with carbon cloth (CC) cathode pyrolyzed with NDC‐M100/Fe₃O₄ at 700°C achieved higher ORR activity compared with the commercial Pt/C under same operational conditions. It also exhibited excellent crystalline structure according to high‐resolution transmission electron microscope (HRTEM) analysis. Moreover, using NDCN/Fe₃O₄ can facilitate further Fenton‐like reaction for the treatment of wastewater. Chemical oxygen demand (COD) removal efficiency of the reactor was 78% with maximum power density of 1.57 W/m³ in 216 hours. Thus, an innovative multi‐processing method with feasibility for enhanced wastewater treatment and improved power performance of the MFC was investigated. This can be effectively applied in related alternative energy production techniques and bio‐electrochemical systems in the future.     

Pretreatment of second and third generation feedstock for enhanced biohythane production: Challenges,recent trends and perspectives

In the context of biofuel production and achieving sustainable bioeconomy, the use of lignocellulosic and algae biomass in anaerobic fermentation processes yields biohythane that has a typical composition of 10–15% H₂, 50–55% CH₄ and 30–40% CO₂. Using organic biomass-based substrates has been shown to minimize environmental impacts due to the versatile production of high-value products under normal operating conditions that are practically achievable. However, the biohythane yield depends on different factors such as the biomass type, the organic loading rate, soluble metabolic products formed, the type of fermentation (single/dual stage) and the pretreatment strategy adopted for the biomass. Different pretreatment strategies based on physical, chemical and biological processes have been proposed in the literature. In this review, improvements in biohythane yield as a result of these pretreatment strategies, the need/effect of inoculum enrichment, the effects of pH, temperature, trace element addition and organic loading rate has been reviewed. Finally, the major developments of improving biohythane yield due to the addition of co-substrates and the current trends are discussed.