Peat properties of a tropical forest reserve adjacent to a fire-break canal

Tropical peat comprises decomposed dead plant material and acts like a sponge to absorb water,making it fully saturated.However,drought periods dry it readily and increases its vulnerability to fire.Peat fires emit greenhouse gases and particles contributing to haze,and prevention by constructing fire-break canals to reduce fire spread into forest reserves is crucial.This paper aims to determine peat physical and chemical properties near a fire-break canal at different fire frequency areas.Peat sampling was conducted at two forest reserves in Malaysia which represent low fire frequency and high fire frequency areas.The results show that peat properties were not affected by the construction of a fire-break canal,however lignin and cellulose content increased significantly from the distance of the canal in both areas.The study concluded that fire frequency did not significantly influence peat properties except for porosity.The higher fibre content in the high frequency area did not influence moisture content nor the ability to regain moisture.Thus,fire frequency might contribute differently to changes in physical and chemical properties,hence management efforts to construct fire-break canals and restoration efforts should protect peatlands from further degradation.These findings will benefit future management and planning for forest reserves.

Impacts of different drying strategies on drying characteristics,the retention of bio-active ingredient and colour changes of dried Roselle

The drying kinetics of Roselle （Hibiscus sabdariffa L） of variety Terengganu （UMKL-1） and the quality attribution of Roselle were studied. The experiments were conducted using four different drying methods, including solar greenhouse drying （SD）, solar greenhouse with intermittent heat pump drying （SIHP）, hot air drying （HA） and heat pump drying （HP）. Among the four drying methods, HP achieved the highest drying rate at a range from 0.054 g H20-（g DM）-1. rain-1 to 0.212 g H20-（g DM）-1. rain 1 while SD had the lowest drying rate, measured at 0.042 g H2O. （g DM） 1.min- 1. The analysis on colour kinetics revealed that there is no significant colour loss （p 〉 0.05） observed from HP＇s dried Roselle. Greater amount of flavonoid compounds i.e. protocatechuic acid was found in SD and SIHP dried finished product whereas HP＇s dried Roselle contains higher percentage of catechin as compared to other drying methods.

Short-Term Field Decomposition and Physico-Chemical Transformation of Jatropha Pod Biochar in Acidic Mineral Soil

Details regarding field decomposition and transformation of biochar in Malaysia are scarce. The objectives of this study were to investigate the physico-chemical changes experienced by Jatropha pod biochar (JPB) in acidic mineral soil under field condition. Elemental composition was determined using CHNS-O analyzer and surface area with Brunauer-Emmett-Teller (BET) method. The JPB surface chemistry and structure were studied using the Fourier Transform Infrared (FTIR) spectroscopy and 13C solid state Nuclear Magnetic Resonance (NMR) spectroscopy, respectively. The JPB short-term decomposition was investigated by using a litter bag study and decomposition data were best fitted by a hyperbolic decay model compared to an exponential decay model because no significant dry weight loss was detected after 4 months. Two phases (volatile and near stagnant) were detected for JPB field decomposition. The volatile phase was due to rapid loss of labile fraction such as carbohydrate during the initial 4 months. The near stagnant phase was probably due to adsorption of organic matter and soil minerals. The JPB was fragmented into smaller pieces, encouraging surface adsorption. Redox reaction was prominent as shown by the production of hydroxyl, carboxylic and phenolic functional groups. The JPB became more recalcitrant after 12 months of application to the soils.

Overview on Application of Response Surface Methodology （RSM） in Treatment of Palm Oil Mill Effluent （POME）

There are many factors affecting the performance of a treatment system especially in the treatment of palm oil mill effluent （POME） as its contains high amounts of suspended solid, low pH, high salt content and high chemical oxygen demand （COD）. However, one factor at a time approach is complicated method in establishing relationship between multiple parameters. Response surface methodology （RSM） is a recommended approach as it is widely used to analyze and study the interactions between multiple parameters and provides optimum output as well as minimizing the defects which result in good treatment system. This paper overviews the recent and current research in the application of RSM in optimizing the treatment development of POME.

Fractionation of Palm Kernel Oil by Short Path Distillation

Fractionation of palm kernel oil （PKO） by short path distillation （SPD） at two feed flow rates （135 g/h and 195 g/h） and six distillation temperatures, TD,s （200, 210, 220, 230, 240 and 250 ℃） was investigated. Other distillation parameters, such as vacuum pressure （0.001 mbar）, blade rotation speed （400 rpm） and temperature of the feed material （60 ℃） were kept constant. The fractionated products, known as residue and distillate, were analysed for physico-chemical properties including fatty acid composition （FAC）, triacylglycerol （TAG） composition, slip melting point （SMP）, thermal analysis by differential scanning calorimetry （DSC） and solid fat content （SFC）. Product yield was measured as well. Crystallisation behaviour of PKO and the fractionated products were studied by measurement of isothermal crystallisation, Tc,. at 0, 5, 10, 15, 20 and 25 ℃. The distillates, collected at all fractionation temperatures, were enriched with caprylic, capric and lauric acids. These fractions were also concentrated with low molecular weight and C36 TAGs. Distillates obtained at higher TDis （230-250 ℃） exhibited higher in SMP and SFC. On the other hand, the residual oils collected at all fractionation temperatures contained higher amount of long-chain fatty acid and palmitic acid. These fractions were enriched with high molecular weight TAGs. Residues obtained at lower Tois （200-220 ℃） were low in SMP and comparable SFC with PKO. Changes in fatty acid and TAG composition resulted in different crystallisation behaviour of the fractions. Distillates collected at all fractionation temperatures crystallised in a sharper peak while residues obtained at higher T Dis （230-250 ℃） showed broader crystallisation peaks, as shown by the DSC thermograms.

A facile and green synthetic approach toward fabrication of starch-stabilized magnetite nanoparticles

A facile and green synthetic approach for fabrication of starch-stabilized magnetite nanoparticles was implemented at moderate temperature. This synthesis involved the use of iron salts, potato starch,sodium hydroxide and deionized water as iron precursors, stabilizer, reducing agent and solvent respectively. The nanoparticles（NPs） were characterized by UV-vis, PXRD, HR-TEM, FESEM, EDX, VSM and FT-IR spectroscopy. The ultrasonic assisted co-precipitation technique provides well formation of highly distributed starch/Fe3O4-NPs. Based on UV–vis analysis, the sample showed the characteristic of surface plasmon resonance in the presence of Fe3O4-NPs. The PXRD pattern depicted the characteristic of the cubic lattice structure of Fe3O4-NPs. HR-TEM analysis showed the good dispersion of NPs with a mean diameter and standard deviation of 10.68 4.207 nm. The d spacing measured from the lattice images were found to be around 0.30 nm and 0.52 nm attributed to the Fe3O4 and starch, respectively. FESEM analysis confirmed the formation of spherical starch/Fe3O4-NPs with the emission of elements of C, O and Fe by EDX analysis. The magnetic properties illustrated by VSM analysis indicated that the as synthesized sample has a saturation magnetization and coercivity of 5.30 emu/g and 22.898 G respectively.Additionally, the FTIR analysis confirmed the binding of starch with Fe3O4-NPs. This method was cost effective, facile and eco-friendly alternative for preparation of NPs.

OPTICAL BAND GAP AND CONDUCTIVITY MEASUREMENTS OF POLYPYRROLE-CHITOSAN COMPOSITE THIN FILMS

Electrical conductivity and optical properties of polypyrrole-chitosan（PPy-CHI） conducting polymer composites have been investigated to determine the optical transition characteristics and energy band gap of composite films.The two electrode method and I-V characteristic technique were used to measure the conductivity of the PPy-CHI thin films,and the optical band gap was obtained from their ultraviolet absorption edges.Depending upon experimental parameter,the optical band gap（E_g） was found within 1.30-2.32 eV as estimated from optical absorption data.The band gap of the composite films decreased as the CHI content increased.The room temperature electrical conductivity of PPy-CHI thin films was found in the range of 5.84×10^（-7）-15.25×10^（-7） S·cm^（-1） depending on the chitosan content.The thermogravimetry analysis（TGA） showed that the CHI can improve the thermal stability of PPy-CHI composite films.

The flow behavior of powder stearin-based methyl ester sulfonates and the effect of glidant

The preparation and behavior of powder stearin-based methyl ester sulfonates(MES)with the addition of builder as a glidant agent was studied.MES is an anionic surfactant and its performance is equivalent to petroleum-based linear alkylbenzene sulfonates(LAS),the workhorses of the detergent industry.At the same time,zeolites or soda ash were the alternative builders for non-phosphate-based detergent.The behavior of powder MES properties was measured in terms of morphology,particle size,cohesion,caking,and compaction.Before that,these palm stearin-based MES of carbon chain 16–18 with ratios of 98:2,80:20,and 60:40 in flakes were ground using a high shear mixer by 23,000 rpm to produce powder particles.Decreasing the particle size of MES powder can reduce the powder's cohesion,caking,and compaction.The addition of zeolite or soda ash as a glidant in powdered MES can improve the caking behavior.The high stearic in MES greatly influenced getting fine particle powders and required more glidant agents.This powder MES with excellent powder characteristics can perform well as a bio-based cleaning product.