bluuebunny/crossref_metadata_2025_split huggingface dataset:
Some important properties of strandboard manufactured from andong bamboo (Gigantochloa pseudoarundinacea)
Authors: Sulastiningsih I M , Indrawan D A , Trisatya D R 
Published: August 2019

Abstract
Andong bamboo (Gigantochloa pseudoarundinacea) is one of the most important bamboo species widely planted in West Java, Indonesia, and play a prominent role in the rural economy. The bottom and the middle parts of Andong bamboo culms are suitable for laminated bamboo lumber raw material. To improve the efficiency of bamboo utilization, the upper part of Andong bamboo culms were use as raw material for strandboard production. The objective of the study was to determine the effect of strand length and specific pressure on the properties of bamboo strandboard. Laboratory scale of bamboo strandboards were fabricated using three different strand lengths (75, 100, and 150 mm), two different specific pressures applied (25 kg/cm2 and 30 kg/cm2) and glued with phenol formaldehyde with the targeted density of 0.75 g/cm3. Some physical and mechanical properties of bamboo strandboards were determined. Results showed that the average physical properties of bamboo srandboards were 9.3% (moisture content), 0.76 g/cm3 (density), 3.1% (thickness swelling), 1.6% (wide expansion), and 25.1% (water absorpsion). The average mechanical properties of bamboo srandboards were 760.5 kgf/cm2 (MOR), 92.3 103kgf/cm2 (MOE), 5.6 kgf/cm2 (IB), and 56.5 kgf (screw holding power). Some physical and mechanical properties of bamboo strandboard were significantly affected by strand length and specific pressure.
Structural and Mechanical Properties of Carbon-Carbon Biocomposites
Authors: Tahir D , Sattar S , Fatimah S , Rauf N , Armynah B 
Published: August 2019

Abstract
Carbon-carbon composites (C/C composites) have been synthesized from organic sawdust as a carbon filler material and carbon asphalt as matrix of composites. The structural and mechanical properties of carbon-carbon composites from sawdust-asphalt are focused in this experiment. The structural has been characterized by using FTIR, XRD and XRF. The mechanical properties has been resulted from hardness, strength, and attrition testing. According to XRF data, CaO is the main content from carbon filler in composite decrease with increasing carbon asphalt matrix and vice versa for SO3 as the main content from carbon tar as a matrix. Changing structure of C/C composites indicated sawdust as carbon has been bound to asphalt as carbon composites. Beside this, adding carbon to carbon composites shows increasing hardness from 6,57 to 9,27 kg/mm2, strength of sample from 11,90 to 18,56 N/mm2, and decreasing attrition of material from 1,64 to 0,28 gr. According to the data shows that adding sawdust to asphalt makes increasing hardness and strength of C/C composites. It means that the C/C composites from organic material sources has a good material composites which has low degradation under high temperature, economically, and eco-friendly to apply in asphalt as material of road construction. It means that organic material very potential as a carbon-carbon composite materials for various applications.
Citric acid, an environmentally friendly adhesive and wood impregnation material-review of research
Authors: Cahyono T D , Syahidah  
Published: August 2019

AbstractCitric acid’s potency to be adhesive is proven with an increasing quality of product bonding resulted from wood and other lignosellulosic materials. Wood waste, bagasse, sorghum and corn stalks, and bamboo are quality particleboard materials after addition of 20% citric acid. Moulding made of a mixture of tree bark and citric acid with the same concentration is also able to pass repeated boiling test without having any damage. Ester bond between wood’s hydroxyl group and citric acid’s hydroxyl group is formed at 180ºC and gets more optimal as the pressing temperature increases during production process. This results in an increase of board’s physical-mechanical properties pursuant to the standard. Some researches remain presenting non-standard test parameters and this is a challenge to be answered with further research. The density of Samama wood impregnated with 10% citric acid has its density increased between 17.11% and 20.13%. Samama wood does not experience a recovery of set after it has been pressed for 50 minutes at 180°C.
Characteristics of the Cement Board Using CO2 Injection Technology from Wood and Non-Wood Species
Authors: Taskirawati I , Agussalim A , Baharuddin B , Suhasman S 
Published: August 2019

Abstract
The fundamental weakness of the technology in manufacturing cement board is that the curing process takes a long time, which is about 28 days. CO2 injection technology has been shown to accelerate the hardening process. However, each of the wood species has a different response due to the presence of inhibitors, namely extractive component. This study aims to compare the characteristics of CO2 injection cement boards from three wood species. These three species came from hardwood, softwood, and non-wood groups, namely agathis (Agathis sp.), Gmelin (Gmelina arborea) and parring bamboo (Gigantochloa atter), respectively. The type of cement used was Portland Cement Composite (PCC). The three cement boards were made using the CO2 injection method. The characteristics of the cement board were tested according to JIS A 5417–1992. The results showed that agathis has good characteristics in terms of mechanical properties. Both Internal bonding and modulus of elasticity were better than others, but not with its modulus of rapture. As for physical properties, parring bamboo actually showed good performance. However, in general, these three species of cement boards did not meet the standard.
Characteristic of Chitosan Adhesive from Shell Shrimp Litopenaeus vannamei and Their Application For Producing Particleboard
Authors: Ningsi D W , Suhasman  , Saad S 
Published: August 2019

Abstract
The shrimp shell that rich compounds of chitin can be converted to produce polysaccharides called chitosan. The chitosan can be utilized as bioadhesive for substitute chemical based adhesive for producing particleboard. The purpose of this study was to evaluate the effect of different concentration acetic acid (CH3COOH) as the solvent to made chitosan adhesive and physical and mechanical properties of the produced particleboard by using sawdust waste. Chitosan adhesive formulation will be used as an adhesive by dissolving chitosan powder with CH3COOH solvent. This research focused on optimization the solvent content wich is CH3COOH in different concentration such as 0.5%, 2% and 4%. Particleboard with size of 25 cm x 25 cm x 0.7 cm with 8%, target density 0.75 g/cm3 were produced using sawdust waste of Paraserianthes falcataria. The processing condition were 180°C in temperature during 12 minutes with pressure of 25 kg/cm2. The research showed, there is no particular trend in particle board characteristics related to solvent concentration. Physical and mechanical Properties fulfill requirement of JIS A 5908-2003 for Moisture Content, MOE and IB. The produced particleboard that using chitosan as bioadhesive and sawdust waste as particle is potentially to be developed technically based on the quality of the particleboards produced.
Mathematical Modelling Time Dependent for Heat Transfer Process in Homogenous Composite ZnO/Activated CNF
Authors: Latief M F , Tahir D , Juarlin E , Suarga  
Published: August 2019

Abstract
A theoretical study of heat transfer on composite Zinc Oxide (ZnO)/Activated Carbon Nanofibers (CNF) by using mathematical model from diffusion equation for stationary composite with various heating time was studied. The equation and boundary conditions are interpreted by using Taylor series expansion to obtain a steady-state numerical solution from the Jacobi iteration algorithm. The composites where put inside the furnace model by filaments on the two sides of the walls as the source of heat (general model for furnace). By using this model, the position of sample to receive the homogeneous temperature determined. We compared the steady-state and unsteady-state conditions to identify the temperature distribution at real-time. The results show that the heat distribution will reach an asymptotic state by performing a numerical analysis is 200 K and 300 K for 25 minute time of heating. In this study, shows the efficient way for annealing homogenous materials to identify the position inside the furnace which can be used as a guide to receive the homogenous temperature during the annealing processes.
Spatial Analysis For Pinus merkusii Land Suitability At Agroforestry Land In Telagah Village Sumatera Utara Indonesia
Authors: Rahmawaty  , Frastika S , Rauf A 
Published: August 2019

Abstract
Pinus (Pinus merkusii) is commonly found in North Sumatra Forest. Community of Telagah Village, Sei Binge Sub District, Langkat, North Sumatera, generally manage the land with agroforestry system. Pinus is the one of agroforestry constituent in the community land in Telagah Village. This study aimed to analyse the suitability of the land for pinus in Telagah Village Sei Bingai Sub District, Langkat District, North Sumatra, Indonesia. This research was conducted on May to September 2018. The survey method was conducted to collect soil samples in the field. Spasial analysis for pinus land suitability was evaluated based on the matching method. The reference and criteria were adopted from the Land Suitability for Agricultural Plants by the Centre for Soil and Agroclimate Research, Bogor-Indonesia. The Geographic Information System (GIS) was used to map the actual and potential land suitability in Telagah Village. The results showed that the actual land suitability classes for pinus in this area were moderately suitable (S2) (97.26%) and marginal suitable (S3) (2.74%). The potential land suitability classes for pinus in this area were Suitable (S1) (52.04), moderately suitable (S2) (46.04%) and marginal suitable (S3) (1.92%) in Telagah Village. The temperature (tc) and erosion hazard (eh) were the dominant of limiting factor in this area.
Performance of Particleboard with Varying Jabon Wood and Andong Bamboo Composition Against Subterranean Termite Attack
Authors: Arsyad W M , Trisatya D R , Sulastiningsih I M 
Published: August 2019

AbstractThis study investigated the effect of mixed material composition of jabon (Anthocephalus cadambaMiq.) and andong (Giganthochloa pseudoarundinaceaeSteud.) particleboards on their resistance to subterranean termite (Coptotermes curvignatusHolmgren). Six types of 35cm × 35cm × 1.2 cm particleboards were produced and glued with phenol formaldehyde in the proportion of 100:0, 70:0, 60:40, 50:50, 40:60 and 30:70 for jabon and andong. Those panels were tested according to SNI 727-2014. The results showed that material composition of jabon and andong was significantly influenced weight loss and termite mortality. Particleboard with 30:70 jabon-andong proportions had the lowest weight loss (4.28%) and classified as resistant class. Termite mortality rate escalated as jabon composition in the panel decreased.
Optimization of SC-CO2 Time Conditions and Permethrin Concentration in Laminated Bamboo Production Using Surface Response Methodology
Authors: Uslinawaty Z , Muin M , Putranto B , Suhasman S 
Published: August 2019

Abstract
Supercritical carbon dioxide method has starting to be used as environmental friendly method in preserving wood. It is expected to maintain physical and mechanical properties of bamboo. The purpose of this study was to determine the effect of the duration times of supercritical conditions and permethrin preservative concentrations on optimization of shear strength of laminated bamboo impregnated by using supercritical carbon dioxide in the initial process (blades) and final process (laminated bamboo). The RSM-CCD experimental design was used to determine the effect of duration times of supercritical carbon dioxide for 20, 25, 30, 35, 40 minutes and the effect of permethrin concentrations 0.1, 0.3, and 0.5% against the shear strength of laminated bamboos. Response surface analysis, using 10 version of design expert software, has been done to get the optimum condition which would produce maximum of shear strength. The results showed that permethrin concentrations have stronger influenced (based on RSM analysis) on the shear strength and durability of laminated bamboo than the times of supercritical carbon dioxide conditions. Optimization of the two combinations of increasing shear strength and endurance were supercritical conditions = 22.71 minutes, and preservative permethrin concentration = 0.24%. Shear strength of shear strength and decrease in combination weight is 85 kg / cm2 and 0.38%.
Medicinal Plant inventory at the Agroforestry Land in Buffer Area of Gunung Leuser National Park
Authors: Rahmawaty  , Amalia R , Batubara R , Rauf A 
Published: August 2019

Abstract
The inventory of medicinal plants in North Sumatra Province are important, especially those that are often utilized by the community. This study aimed to map the distribution of medicinal plants (herbs) under the agroforestry land in buffer area Gunung Leuser National Park. This research was conducted in Simpang Kuta Buluh Village, Sei Bingai Sub District, Langkat District, North Sumatra Province. This research was conducted on March to June 2018. The survey method was used by making plots in the field. A Geographic Information System (GIS) was used to analyze the distribution of the medicinal plants and a Global Positioning System (GPS) was used to record the coordinate points of medicinal plants in the area. The results showed that there were found thirty four (34) species of herbs plant in the area with the total of 307 individuals herb,. Sampelulut (Urena lobata L.) was dominant spesies which is found (56 individuals) in this area, followed by Asar-asar (Selaginella deoderleinii) (42 individuals) and Senduduk Bulu (Clidemia hirta) (30 individuals). Constituent plants in Agroforestry land, namely: Mahoni (Swietenia mahagoni), Durian (Durio zibethinus), Karet (Hevea brasiliensis), Pisang (Musa paradisiaca), Angsana (Pterocarpus indicus), Coklat (Theobroma cacao L.), Petai (Parkia speciosa), Cengkeh (Syzygium aromaticum), Asam Glugur (Garcinia atroviridus, and Kelapa (Cocos nucifera). The data of medicinal plants distribution is vital to provide information for community, researchers, and government.
Improving Degradation Ability of Composite Starch/Chitosan by Additional Pineapple Leaf Microfibers for Food Packaging Applications
Authors: Mutmainna I , Tahir D , Gareso P L , Ilyas S , Saludung A 
Published: August 2019

Abstract
Structural, mechanical properties, and bonding characteristic of plastic bio-composites (starch/chitosan) with an additional Pineapple leaf microfibers (PLM) for 3%, 6% and 9% were carried out by using X-Ray diffraction (XRD), tensile strength test, and Fourier transform infra-red (FTIR) spectroscopy, respectively. The value of tensile strength shows highest for plastic bi-composite with 9% PLM and also XRD spectra shows the amorphous phase with new structure was formed for all bio-composite + PLM. FTIR spectra shows the strong bonding formation as the effect of PLM indicated by increase the intensity of C-H and C=C bond with increasing the amount of PLM. From the biodegradation test shows the PLM strongly influenced to the degradation ability of bio-composite and the highest is for 9% PLM (>80% ). In addition, the lowest browning index is about 37.5% for bio-composite with additional 9% PLM which was determined by using fresh cherry (Muntingia calabura. L). It’s indicated that the plastic bio-composite with an additional PLM shows high potentials for new food packaging applications.
Surface photovoltage spectroscopy of semiconductor materials for optoelectronic applications
Authors: Donchev V 
Published: August 2019

Abstract
The present contribution reviews the basic principles of the surface photovoltage (SPV) spectroscopy in the metal-insulator-semiconductor operation mode emphasizing on the crucial necessity of combined analysis of the SPV amplitude and phase spectra for the understanding and correct interpretation of the experimental data. Several results are presented obtained by the application of the SPV spectroscopy to semiconductor bulk materials and nanostructures designed for applications in optoelectronic devices. These include: (i) AlAs/GaAs superlattices with GaAs embedded quantum wells for optical emitters, (ii) multilayer structures with InAs/GaAs submonolayer quantum dots for infra-red photodetectors, (iii) Si nanowires for light trapping in solar cells and (iv) dilute nitrides Ga(In)As(Sb)N layers for photovoltaic applications. Valuable information about the investigated materials is obtained such as the optical absorption spectrum defined by the quantum confinement and excitonic effects, the optical transition energies, the effect of surface states on the minority carrier diffusion length, the type of the residual doping in the layers, and the alignment of the energy bands across the structures. It is shown that the SPV spectroscopy is a powerful highly sensitive non-destructive technique for room temperature characterization of various semiconductor materials applied in optoelectronics.
Causality in quantum field theory with classical sources
Authors: Skagerstam Bo-Sture K , Eriksson Karl-Erik , Rekdal Per K 
Published: August 2019

Abstract
In an exact quantum-mechanical framework we show that space-time expectation values of the second-quantized electromagnetic fields in the Coulomb gauge in the presence of a classical conserved source automatically lead to causal and properly retarded ℏ-independent electromagnetic field strengths. The classical ℏ-independent and gauge invariant Maxwell’s equations naturally emerge in terms of quantum-mechanical expectation values and are therefore also consistent with the classical special theory of relativity. The fundamental difference between interference phenomena due to the linear nature of the classical Maxwell theory as considered in, e.g., classical optics, and interference effects of quantum states is clarified. In addition to these issues, the framework outlined also provides for a simple approach to invariance under time-reversal, some spontaneous photon emission and/or absorption processes as well as an approach to Vavilov-Čherenkov radiation. The inherent and necessary quantum uncertainty, limiting a precise space-time knowledge of expectation values of the quantum fields considered, is, finally, recalled.
Portugal under austerity: from financial to renewable crisis?
Authors: Andreas Jan-Justus , Burns Charlotte , Touza Julia 
Published: August 2019

Abstract
Portugal was hit hard by the global financial crisis, with concomitant effects upon the development of its renewable energy sector. The imposition of austerity has had negative impacts upon the further development of the Portuguese renewables sector, prompting the question of whether we have seen a critical juncture that will lead to a new policy trajectory. Historical institutionalist analysis demonstrates a range of unintended consequences arising from the pursuit of austerity in Portugal, yet no true critical juncture to the country’s commitment to renewable electricity. The path dependent structure of the Portuguese electricity market and the export bottleneck between the Iberian Peninsula and Central Europe are identified as critical variables explaining the sub-optimal policy trajectory. We conclude that resolving this bottleneck will be critical for Portugal to reduce current financial and electricity price pressures, and continue its renewable energy transition.
The relationship of cognitive change over time to the self-reported Ascertain Dementia 8-item Questionnaire in a general population
Authors: Passler Jesse S , Kennedy Richard E , Crowe Michael , Clay Olivio J , Howard Virginia J , Cushman Mary , Unverzagt Frederick W , Wadley Virginia G 
Published: August 2019

AbstractObjectiveThe aim of the study was to examine the relationship between longitudinally assessed cognitive functioning and self-reported dementia status using the Ascertain Dementia 8-item questionnaire (AD8) in a national population-based sample.MethodsThe analysis included 14,453 participants from the REasons for Geographic and Racial Differences in Stroke study. A validated cutoff of ≥2 symptoms endorsed on the AD8 (administered 10 years after enrollment) represented positive AD8 status. Incident cognitive impairment was defined as change from intact to impaired status in the Six-Item Screener score, and cognitive decline was defined by trajectories of Letter “F” Fluency from the Montreal Cognitive Assessment, and Animal Fluency, Word List Learning, and Word List Delayed recall, all from the Consortium to Establish a Registry for Alzheimer’s Disease battery. Logistic regression models controlled for demographics, health variables, and depressive symptoms.ResultsSensitivity and specificity of the AD8 to detect incident cognitive impairment were 45.2% and 78.4%, respectively. Incident cognitive impairment and a one-word decline in WLL increased the odds of self-reported positive AD8 by 96% (95% CI: 1.68–2.28) and 27% (95% CI: 1.17–1.37), respectively. There was a strong association between high depression risk and self-reported positive AD8 in sensitivity analyses.ConclusionsIncident cognitive impairment and high depression risk were the strongest predictors of self-reported positive AD8 in this population-based sample. Our results inform the utility of the AD8 as a self-report measure in a large, national sample that avoids selection biases inherent in clinic-based studies. The AD8 is screening measure and should not be used to diagnose dementia clinically.
MOOMIN – Mathematical explOration of ’Omics data on a MetabolIc Network
Authors: Pusa Taneli , Ferrarini Mariana Galvão , Andrade Ricardo , Mary Arnaud , Marchetti-Spaccamela Alberto , Stougie Leen , Sagot Marie-France 
Published: August 2019

Abstract

Motivation
Analysis of differential expression of genes is often performed to understand how the metabolic activity of an organism is impacted by a perturbation. However, because the system of metabolic regulation is complex and all changes are not directly reflected in the expression levels, interpreting these data can be difficult.

Results
In this work, we present a new algorithm and computational tool that uses a genome-scale metabolic reconstruction to infer metabolic changes from differential expression data. Using the framework of constraint-based analysis, our method produces a qualitative hypothesis of a change in metabolic activity. In other words, each reaction of the network is inferred to have increased, decreased, or remained unchanged in flux. In contrast to similar previous approaches, our method does not require a biological objective function and does not assign on/off activity states to genes. An implementation is provided and it is available online. We apply the method to three published datasets to show that it successfully accomplishes its two main goals: confirming or rejecting metabolic changes suggested by differentially expressed genes based on how well they fit in as parts of a coordinated metabolic change, as well as inferring changes in reactions whose genes did not undergo differential expression.

Availability and implementation
github.com/htpusa/moomin.

Supplementary information
Supplementary data are available at Bioinformatics online.