Properties of resin impregnated oil palm wood (Elaeis Guineensis Jack)

Oil palm wood (OPW) was treated with medium-molecular weight PF resin (mmw-PF) through a modified impregnation-compression method. The method consists of four steps, namely, drying, impregnation, heating, and hot pressing densification. The objective of the study was to optimize the impregnation variables. The overall density of the OPW increased, whereas the density gradient between the two OPW structural elements (namely, parenchyma tissues and vascular bundles) decreased. The weight percent gain (WPG) significantly increased even with a very short impregnation period (i.e. 1 hour). Young`s Modulus of the compression parallel to the grain increased by 15 times (from 170 to 2600 MPa) and the shear strength increased by 7 times (from 1.9 to 13 MPa). The strength of the samples was increased exponentially against density increment. The treatment also made the two OPW structural elements to be strongly bonded that helped in enhancing the durability and machining characteristics of the material

Dichlorido{4-cyclo­hexyl-1-[1-(2-pyridyl-κN)ethyl­idene]thio­semicarbazidato-κ2 N 1,S}phenyl­tin(IV)

The SnIV atom in the title compound, [Sn(C6H5)(C14H19N4S)Cl2], exists within a distorted octa­hedral geometry defined by the N,N′,S-tridentate monodeprotonated Schiff base ligand, two mutually trans Cl atoms, and the ipso-C atom of the Sn-bound phenyl group; the latter is trans to the azo-N atom. The greatest distortion from the ideal geometry is found in the nominally trans angle formed by the S and pyridyl-N atoms at Sn [151.03 (4)°]. With the exception of the cyclo­hexyl group (chair form), the Schiff base ligand is almost planar (r.m.s. deviation of non-H and Sn atoms = 0.053 Å). The nearly orthogonal orientation of the Sn-bound phenyl group [N—Sn—C—C torsion angle = 70.8 (5)°] to the planar portion of the Schiff base allows for the formation of significant intra­molecular C—H⋯Cl inter­actions which preclude the Cl atoms from participating in N—H⋯Cl hydrogen bonds. Instead, C—H⋯π contacts, involving methyl­ene H and the Sn-bound phenyl group, lead to the formation of supra­molecular chains that pack in the bc plane. Connections between these layers are of the type C—H⋯Cl

Biological durability of injection moulded wood plastic composite boards

The steadily growth of Wood Plastic Composite (WPC) in exterior applications resulted a need to understand their durability. In Malaysia, the durability of WPC is not only affected by mold and decay fungi as biodegradation agents but also due the termites attack. Therefore, this study was carried out to investigate the durability of WPC produced from different wood fine loadings (60, 65 and 70%) and MAPP (1, 2, 3 and 4%) concentration. The aim of this study is to determine the optimum WPC formulation associate with higher durability against biodegradation agents. Commercial polypropylene, wood fines and coupling agent premixed in dumper mixer for 30 min prior to extrusion process at temperature of 190°C using 110 mm counter-rotating twin-screw extruder. The premixed raw materials were then subjected to injection moulded using 40 ton press moulding machine and pressed into size of 30 mmx30 mm and 3 mm thick board. Biological durability tests were carried out according to ASTM D4445 for mold, ASTM method D 2017 for decay fungi and ASTM D 3345 for termites. From the result, 70% wood fine loading showed significantly lower durability due to the insufficient encapsulation of wood fine with polymer matrix. Higher percentage of coupling agent (MAPP) used in the WPC boards will provide higher durability of WPC. Conclusively, the optimum formulation for WPC i.e., 4% MAPP and 60% wood fine loading gave the highest protection against mold, decay fungi and termites

Thermal, physical properties and flammability of silane treated kenaf/ pineapple leaf fibres phenolic hybrid composites

Silane treated pineapple leaf fibre (PALF) and kenaf fibre were analyzed by Thermogravimetric analysis (TGA) that indicated the treated hybrid composite showed better thermal stability as compared to untreated hybrid composites. Dynamic mechanical analysis was carried out to evaluate the storage modulus (E′), loss modulus (E″), and tan delta as a function of temperature. Storage modulus of treated hybrid composites displayed highest storage and loss modulus as in comparison of untreated hybrid composites. The peak heights of tan α were highest in treated hybrid composites. Cole-Cole analysis was also carried out to understand the phase behaviour of the composite samples. Thermal mechanical analysis was used to study mechanical stability of hybrid composites in the presence of temperature. The effect of different fibre ratios in hybridization on density, void content, water absorption (WA), thickness swelling (TS) of PALF/KF hybrid composites were also analyzed. Treated hybrid composites were not very affective to improve the flammability of PALF/KF hybrid composites. The overall results showed that treated PALF/KF/phenolic hybrid composites improved the thermal and dynamic mechanical properties over untreated PALF/KF hybrid composites

Bis{4-methylbenzyl 2-[4-(propan-2-yl)benzylidene]hydrazinecarbodithioato-κ2N2,S}nickel(II): crystal structure and Hirshfeld surface analysis

The complete molecule of the title hydrazine carbodithioate complex, [Ni(C19H21N2S2)2], is generated by the application of a centre of inversion. The NiII atom is N,S-chelated by two hydrazinecarbodithioate ligands, which provide a trans-N2S2 donor set that defines a distorted square-planar geometry. The conformation of the five-membered chelate ring is an envelope with the NiII atom being the flap atom. In the crystal, p-tolyl-C—H...π(benzene-iPr), iPr-C—H...π(p-tolyl) and π–π interactions [between p-tolyl rings with inter-centroid distance = 3.8051 (12) Å] help to consolidate the three-dimensional architecture. The analysis of the Hirshfeld surface confirms the importance of H-atom contacts in establishing the packing

Synergistic effect of oil palm based pozzolanic materials/oil palm waste on polyester hybrid composite

This research work aims to investigate the synergistic effect of pozzolanic materials such as oil palm ash (OPA) and oil palm empty fruit bunch (OPEFB) on the developed hybrid polymer composites. The OPEFB and OPA fillers of different particle sizes (250, 150, and 75 µm) were mixed at OPEFB:OPA ratios of (0:100; 20:80; 40:60; 60:40; 80:20 and 100:0) and incorporated into an unsaturated polyester resin. Furthermore, both mechanical and morphological properties of the composites were analyzed and it was found that tensile, flexural, and impact properties were significantly improved at OPEFB:OPA of 75 µm particle size hybridization of the polymer. The increase of OPEFB to OPA filler ratio up to 80:20 significantly improved the tensile properties of the composites while 40:60 ratio of 75 µm gave the optimum filler ratio to obtain the highest flexural and impact properties of the composites among all studied samples. Scanning electron micrograph images showed strong particle dispersion of the embedded fillers with resin which explained the excellent mechanical strength enhancement of the composite

Anomaly gait detection in ASD children based on markerless-based gait features

Children with autism are known for their difficulties in social interaction, communication, and behaviour characteristics. Hence, this study proposed to develop a markerless-based gait method for anomaly gait detection in children with autism spectrum disorder (ASD). Firstly, a depth sensor is used during walking gait data collection of the 23 ASD children and 30 typical healthy developing (TD) children. Further, these walking gait data are divided into the Reference Joint (REF) and Direct Joint (DIR) features. For each type, five sets of features are derived that represents the whole body, upper body, lower body, the right and left side of the body. The three classifiers used to validate the effectiveness of the proposed method are Naïve Bayes (NB), Support Vector Machine (SVM), and Artificial Neural Network (ANN). Results showed that the highest accuracy, precisely 94.22%, is achieved using the ANN classifier with DIR1 gait features representing the whole body. The highest sensitivity and specificity obtained are 94.49% and 93.93% accordingly. In addition, the proposed markerless model using the DIR1 gait features and the ANN as classifier also outperformed previous studies that have utilised the marker-based model. This promising result showed that the proposed method could be used for early intervention for the ASD group. The markerless-based gait technique also has fewer experiment protocols, thus causing the ASD children to feel more comfortable

Properties of particleboards made from Acacia seyal var. using UF-tannin modified adhesives

The aim of this study was to investigate the effect of adding a blend of tannins to commercial urea formaldehyde (UF) on the properties of particleboard made from wood particles of Acacia seyal var. seyal. The tannins were extracted from the bark of Acacia seyal var. seyal (Ass) and Acacia nilotica subsp. tomentosa (Ant) with hot water (initial temperature was 90 ºC), using a ratio of powdered b ark to water of 1:6 (w/v). The tested Acacia specie s (Ass and Ant) exhibited high tannin contents (82.18% and 73.09%, respectively). A blend from the two tannin types (B T) was made (1:1 w/w) and added to UF in the form of a concentrated solution (35%) at three different percentages (5%, 10% and 15%, weight/weight). The different UF–BT formulations were used to produce particleboards (340 mm × 340 mm × 10 mm in size). The obtained panels were tested according to the BSEN relevant standards and showed high mechanical properties, compared to the ones produced by solely UF. It was also observed that the addition of BT to UF did not improve the physical properties of the panels (thickness swelling (TS) and water absorption (WA)), but the results obtained were slightly higher than the ones for the UF panels

Optimization of torrefaction conditions for high energy density solid biofuel from oil palm biomass and fast growing species available in Malaysia

Without appropriate treatment, lignocellulosic biomass is not suitable to be fed into existing combustion systems because of its high moisture content, low bulk energy density and difficulties in transport, handling and storage. The aim of this study was to investigate the effects of torrefaction treatment on the weight loss and energy properties of fast growing species in Malaysia (Acacia spp., and Macaranga spp.) as well as oil palm biomass (oil palm trunk and empty fruit bunch). The lignocellulosic biomass was torrefied at three different temperatures 200, 250 and 300 °C for 15, 30 and 45 min. Response surface methodology was used for optimization of torrefaction conditions, so that biofuel of high energy density, maximized energy properties and minimum weight loss could be manufactured. The analyses showed that increase in heating values was affected by treatment severity (cumulated effect of temperature and time). Our results clearly demonstrated an increased degradation of the material due to the combined effects of temperature and treatment time. While the reaction time had less impact on the energy density of torrefied biomass, the effect of reaction temperature was considerably stronger under the torrefaction conditions used in this study. It was demonstrated that each biomass type had its own unique set of operating conditions to achieve the same product quality. The optimized torrefaction conditions were verified empirically and applicability of the model was confirmed. The torrefied biomass occurred more suitable than raw biomass in terms of calorific value, physical and chemical properties. The results of this study could be used as a guide for the production of high energy density solid biofuel from lignocellulosic biomass available in Malaysia

Kaempferol Regresses Carcinogenesis through a Molecular Cross Talk Involved in Proliferation, Apoptosis and Inflammation on Human Cervical Cancer Cells, HeLa

Kaempferol, a flavonoid, contains a plethora of therapeutic properties and has demonstrated its efficacy against cancer. This study aims to unravel the molecular targets that are being modulated by kaempferol on HeLa cells. Various assays were performed, namely: MTT assay, flow cytometry to analyze DNA content and quantitate apoptosis. Quantitative PCR and protein profiling were performed to evaluate the modulated manifestation of different genes involved in apoptosis, cell growth and inflammation. Kaempferol exhibited reduction in cell viability of HeLa cells (IC50 = 50 µM 48 h), whereas it did not show any significant effect on viability of the AC-16 cell line. Kaempferol-impacted apoptosis was definitive, as it induced DNA fragmentation, caused disruption of membrane potential, accumulation of cells in the G2-M phase and augmented early apoptosis. Consistently, kaempferol induced apoptosis in HeLa cells by modulating the expression of various genes at both transcript and protein levels. It upregulated the expression of pro-apoptotic genes, including APAF1, BAX, BAD, Caspases 3, and 9, etc., at the transcript level and Bad, Bax, p27, p53, p21, Caspases 3 and 8 etc. at the protein level, while it downregulated the expression of pro-survival gene BCL-2, BIRC8, MCL-1, XIAP, and NAIP at the transcript level and Bcl-2, XIAP, Livin, clap-2 at the protein level. Kaempferol attenuated oxidative stress by upregulating GSH activity and anti-inflammatory response by suppressing NF-kB pathways. Moreover, kaempferol averted rampant cell division and induced apoptosis by modulating AKT/MTOR and MAP kinase pathways. Hence, kaempferol can be considered as a natural therapeutic agent with a differential profile