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Non-woven kenaf fiber (KF) mat reinforced acrylic-based polyester resin composites were prepared by an impregnation process followed by compression molding. They were exposed to durability test of accelerated weathering and water absorption. Accelerated weathering test through UV irradiation caused modification in chemical, mechanical, surface appearance, and color change of the composites. Two competing reactions occurred throughout the exposure period, i.e., post-crosslinking and photo-oxidation process. FTIR analysis revealed that the former occurred at the early stage of exposure while the latter toward the end of the exposure, exhibited by an accentuated increase in carbonyl and vinyl index. The post-crosslinking process contributes to the improvement in flexural properties and thermal stability of the composites, whereas the oxidation process does not. SEM observation showed that the degradation by photo-oxidation resulted in the formation of voids and blisters on composite's sample. Water uptake of all composites was found to follow Fickian behavior. Good recoveries (exceeding 79%) of flexural properties were obtained upon re-drying. However, a significant reduction in flexural strength and modulus was obtained in the wet state condition. SEM observation revealed that full recovery was not possible because of the impairment of the—matrix interfacial region. Relatively higher flexural properties were exhibited by alkali-treated KF composites even after the durability test due to the improved strength and—matrix adhesion following the treatment.

To determine the effect of investment decisions, funding decisions and company size on business risk in hotel, restaurant and inn division companies recorded on the Indonesia Stock Trade, the period utilized in this think about is 5 (five) a long time, beginning from 2017-2021. This think about employments a quantitative approach. The populace in this think about is 35 companies in the hotel, restaurant and hotel sector which are still recorded on the Indonesia Stock Trade for the period 2017-2021. The sampling technique used was purposive sampling and a sample of 12 companies was obtained. The information examination method utilized is board information relapse examination with the assistance of the Eviews 9 and SPSS programs. The results of the study show that investment decisions have no effect on business risk and are not significant. Funding decisions have a positive and significant effect on business risk and company size has no effect on business risk and is not significant on business risk. Simultaneously investment decisions, funding decisions and company size have a positive and significant effect on business risk in the 2017-2021 period. [ABSTRACT FROM AUTHOR]

Chitin is a naturally abundant polymer and most of it was used as a surfactant and cosmetic raw materials. Chitin be able to derive from natural sources like shrimp shell waste. The aim of this research was to study the kinetic model of chitin demineralization with approach to shrinking core model (SCM) with variation of hydrochloric acid concentration. There models were used: Fluid Film Layer Diffusion, Ash Layer Diffusion and Chemical Reaction. It was began with deproteination at first with NaOH 3,5 % and continued with demineralization using hydrochloric acid at concentration 0,3 N; 0,6 N; 0,9 N and 1,2 N with variation of reaction time at 15, 30 and 15 minute. The calcium content in the product was analyzed after it was dried in the air oven. The results showed calcium concentration decrease along with increasing of hydrochloric acid concentration. It get kinetic model at concentration 0,3 N of hydrochloric acid usage with form: 1−rcR3=XB with the highest value of R2 is 0,9555 and the smallest percentage error is 5,92%. Meanwhile with usage of hydrochloric acid at concentration 0,6 N; 0,9 N and 1,2 N were get kinetic model with form: tτ=1−31−XB2/3+21−XB with the highest value of R2 is 0,9794.

Arbitration has witnessed significant development in recent years, and the judiciary has played an active role in its advancement through innovative interpretations, flexible reasoning, and the recognition of principles that helped fill gaps faced by arbitration bodies. The role of the judiciary has been evident in defining the scope of arbitration agreements. Judicial precedents have allowed the extension of the effects of arbitration agreements to non-signatories in specific circumstances. The judiciary has embraced interpretations that permit arbitration to operate outside of specific domestic laws, expanding the realm of commercial arbitration beyond the confines established by national legislation. It has adopted a broad understanding of commercial activity to include actions that may not be considered commercial under national laws. Notable contributions by the judiciary include laying the groundwork for the principle of the independence of the arbitration clause and the doctrine of kompetenz-kompetenz (the competence of the tribunal to determine its own jurisdiction). These developments were responses to practical justifications aimed at preventing the nullification or collapse of the arbitration process when the agreement containing the arbitration clause is deemed invalid. The doctrine of kompetenz-kompetenz has also helped prevent delay tactics and achieve expeditious resolution. This has been reinforced by the adoption of the Estoppel Rule, which gives power to waste the objector's defenses if a blatant contradiction is found in their position: participating seriously in the arbitration proceedings for a long time and then invoking the invalidity of the arbitration agreement. [ABSTRACT FROM AUTHOR]

The purpose of this study is to determine the direct and indirect effects of business networks and online marketing capabilities on the performance of SMEs fostered by PT. Perkebunan Nusantara III through a partnership program. The population and sample are from 100 SME partners who are considered successful in developing their business. Research questionnaires were used to obtain research data in the form of primary data. While the data analysis using path analysis using the Smart PLS approach. The results showed that the business network directly had a significant effect on the partnership program and the performance of the SMEs fostered by PT. Perkebunan Nusantara III. Directly, the ability of online marketing has no significant effect on the partnership program but does affect the performance of the SMEs fostered by PT. Perkebunan Nusantara III. Lastly, indirectly, the partnership program has a significant role in mediating the business network on the performance of the SMEs fostered by PT. Perkebunan Nusantara III, while online marketing capabilities have no significant effect on the performance of the SMEs fostered by PT. Perkebunan Nusantara III. [ABSTRACT FROM AUTHOR]

Optimum process condition of preparation of porous hydroxyapatite bodies has been successfully achieved using response surface methodology. This optimum process condition is gotten by optimizing the three parameters: porosity, density and compressive strength, through response surface methodology based on central composite design using design-Expert software. This research used replica method to produce porous hydroxyapatite bodies. Analysis of XRD, SEM, and compressive strength test are used to characterize the produced porous hydroxyapatite bodies. The results were then evaluated by response surface methodology method using design-Expert software. Porous hydroxyapatite was characterized by using XRD, SEM, and compressive strength test. Porous hydroxyapatite bodies were obtained with 54.3–65.4% porosity, 1.085–1.436 g/cm3 density, 1.4–6.8 MPa compressive strength, and 70.68–89.13 µm pore sizes. The RSM results revealed that density and porosity were affected by the parameters with R2 0.9218 and 0.9902, respectively, and R2adj 0.8513 and 0.9814, respectively. The optimum condition was obtained at process condition of 9 g hydroxyapatite, 12% sago starch, and 2.5%wt darvan821A with compressive strength response 5.7 MPa, 63.1% porosity, and 1.159 g/cm3 density. The desirability value was 0.795 which was close to 1.0 and considered as acceptable value. [ABSTRACT FROM AUTHOR]

The multi-scale hybridisation of alumina (Al2O3) and carbon nanotubes (CNTs) was synthesised with the use of chemical vapour deposition (CVD). The CNTs were grown directly on the Al2O3 particle by utilising a nickel catalyst while being under an atmosphere of methane. When incorporated into the epoxy matrix, the CNT-Al2O3 hybrid filler provided new opportunity for the development of high performance multifunctional composites. The goal of hybridizing CNTs and Al2O3 particles is to avoid CNT agglomeration as a result of van der Waals attractions. The particles of Al2O3 serve as "vehicles" for CNTs so that they can homogenously disperse in the epoxy matrix. As a comparative study, preparation of CNT-Al2O3 was also done through a physical mixing method. The result revealed that compared to the CNT-Al2O3 filler that was physically mixed, the CNT-Al2O3 hybrid filler exhibited a more homogeneous dispersion within the epoxy matrix and it had a higher dielectric constant. Furthermore, compared to the neat epoxy, the dielectric constant of the CNT-Al2O3 hybrid epoxy nanocomposites was enhanced by up to 22%. [ABSTRACT FROM AUTHOR]

Morphology character is the result of interaction between genetic and environmental factor, and the last factor is the dominant factor of variation. Morphometric character of shrimp is required to determine the value of portion of body part that can be consumed, so that it can be used as baseline in designing breeding program. This research aimed to study the variation of morphometric and meristic of Macrobrachium lar population from several rivers i.e. Andai, Wariori, Muara Prafi and Pami, in Manokwari West Papua Province. We found eight morphometric characters which were significanly different (p<0.01) among lar shrimp populations. Among the eight characters, there were three best morphometric characters, body weight (BT), total length (PT), and rostrum length (PR) that could be used for determining the differences between populations. Total number of upper teeth rostrum ranged between 7-9, while lower teeth ranged between 0-5. The meristic characters between populations were not significanlly different (p>0.05). Morphometric characters of Andai and Pami population tended to similar each other as well as those of Wariori and Muara Prafi population. It showed that the similarity of the characters might related to close distance of the rivers. Although the four those rivers came from different upstream source, the closer distance of the M. lar population, the closer genetic relationship of M. lar population. [ABSTRACT FROM AUTHOR]

Magnetite nanoparticles (Fe3O4) are a type of magnetic particle with huge potential for application as a drug carrier due to their excellent superparamagnetic, bioCompatible, and easily modified surface properties. One characteristic of nanoparticles is that they can be controlled by studying the evolution of crystal growth. The purpose of this research is to study the evolution of magnetite-crystal growth and determine the crystal growth kinetics using the Ostwald ripening model. Magnetite nanoparticles were synthesized from FeCl3, citrate, urea, and polyethylene glycol using the hydrothermal method at 220°C for times ranging from 1–12 hours. The characterizations using X-ray diffraction (XRD) indicated that the magnetite began to form after 3 hours synthesis. The crystallinity and crystal size of the magnetite increased with the reaction time. The diameter size of the magnetite crystals was in the range of 10–29 nm. The characterizations using a transmission electron microscope (TEM) showed that magnetite nanoparticles had a relatively uniform size and were not agglomerated. The core-shell nanoparticles were obtained after 3 hours synthesis and had a diameter of 60 nm, whereas the irregular-shaped nanoparticles were obtained in 12 hours and had a diameter of 50 nm. The characterizations using a vibrating sample magnetometer (VSM) revealed that magnetite nanoparticles have superparamagnetic properties. The magnetization saturation (Ms) value was proportional to the degree of crystallinity. The magnetite-crystal growth data can be fitted to an Ostwald ripening model with the growth controlled by the dissolution of the surface reaction (n≈4). [ABSTRACT FROM AUTHOR]

Thin films of Co xCu yO z have been coated on aluminum substrates via sol-gel route using low concentration of copper and cobalt precursors at annealing temperatures in range of 500-650 °C. The coatings were characterized by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), UV-Vis-NIR spectrophotometry, and nanoindentation. The XRD analysis in 2 θ-range of 30°-42° revealed that the coatings exhibited low crystallinity of CoCu2O3, CoCuO2, and CuCoO2. The surface bonding structure analyzed using XPS indicated that the coating contained: Cu (tetrahedral Cu+ and octahedral Cu2+), Co (octahedral Co3+, tetrahedral Co2+, and mixed Co2+ and Co3+), and O (lattice, surface, and sub-surface oxygens). The optical properties characterized using UV-Vis-NIR showed that the reflectance spectra of coatings formed a spectrally solar selective absorber profile associated with the interference peaks and the absorption edges around wavelengths of below 1.2 μm. The maximum absorptance ( α = 75.8%) was shown by coating synthesized at 500 °C. The mechanical properties of coatings showed that the increase of annealing temperature increased the coating's hardness ( H) and the elastic modulus ( E) due to the enhancement of the [CoCuO2/CuCoO2]:[CoCu2O3] oxide phases ratio, as the result, an excellent stability of the wear resistance ( H/E) of around ∼0.035 was recorded. [ABSTRACT FROM AUTHOR]

Filler treatment is one of the recognized methods that can be implemented to improve the mechanical properties of composite materials. However, no research has examined this particular issue from the dynamic perspective. Hence in this study, both untreated and treated polypropylene (PP)/muscovite (M)-layered silicate composites were tested under static and dynamic loadings of up to 1100 s−1, using a universal testing machine and split Hopkinson pressure bar apparatus, respectively. M particles were treated with lithium nitrate and cetyltrimethylammonium bromide as a surfactant, through an ion exchange treatment. This treatment process was successfully proven, using Fourier transform infrared, X-ray diffraction, and transmission electron microscopy analyses. Results show that the treated PP/M specimens with a fine state of dispersion level show better mechanical performances under a wide range of strain rates that were investigated, when compared with the untreated PP/M specimens. In addition, the mechanical properties of both the tested PP/M-layered silicate composites also show great dependency on the strain rate applied, where yield stress, compression modulus, ultimate compressive strength, and absorbed energy steadily increased when the strain rate was increased. However, the yield strain shows a contrary trend. Postdamage analyses were found to be consistent with the mechanical results for both tested specimens. [ABSTRACT FROM AUTHOR]

Polymer-layered silicate nanocomposites containing polypropylene, compatibilisers, muscovite, and organomuscovite were prepared through the hot compression technique. Muscovite particles were initially treated with lithium nitrate, followed by cetyltrimethylammonium bromide, to obtain the organomuscovite through an ion-exchange treatment. Maleic anhydride and polyhedral oligomeric silsesquioxane were used as compatibilisers to modify the polypropylene/organomuscovite nanocomposite systems. The effectiveness of the ion-exchange treatment and the implementations of both compatibilisers were successfully proven using the Fourier transforms infrared, X-ray diffraction, as well as the transmission electron microscopy. The overall thermal properties of the polypropylene/muscovite layered silicate composites were investigated by applying both differential scanning calorimetry and thermogravimetric analysis. It was found that the polypropylene reinforced with organomuscovite recorded higher thermal properties in terms of crystallisation temperature and thermal stability than its counterpart; whereas, the melting temperature and the degree of crystallinity displayed an opposite trend. For the effect of the compatibiliser, it was found that compatibilised polypropylene/organomuscovite nanocomposites recorded higher values of decomposition and crystallisation temperatures than that of non-compatibilised polypropylene/organomuscovite nanocomposites. However, the melting temperature and the degree of crystallinity of compatibilised polypropylene/organomuscovite nanocomposites were slightly lower, as compared to non-compatibilised polypropylene/organomuscovite nanocomposites. [ABSTRACT FROM AUTHOR]

Objective. Ulcerative colitis (UC) is generally considered a disease of the Caucasian populations in developed countries, but its incidence is increasing rapidly in many developing countries, including the Middle East. The objective of this study was to determine the clinical epidemiology of UC in Arabs. Material and methods. This cross-sectional medical record-based descriptive study collected sociodemographic and clinical information on 182 Arab patients with UC in Kuwait. Age at diagnosis, extent and severity of disease were determined according to the Montreal classification. Results. Among the 182 patients, 91 (50.0%) were males. The median age at diagnosis was 28.5 years. Family history of UC was reported by 26 (14.3%) patients. The extent of the disease was limited to the rectum in 34 (18.7%) patients, left sided in 67 (36.8%) and pan colitis in 81 (44.5%). At the time of inclusion in the study, 127 (69.8%) patients were in clinical remission, 53 (29.1%) had mild-to-moderate disease and 2 (1.1%) had severe colitis. Younger age at diagnosis and non-smoking were associated with more extensive colitis. The majority of patients were treated with mesalamine, steroids and immunomodulators, while biologic therapy and surgery were needed in 5% and 4% of the patients, respectively. Conclusions. UC presents more commonly at younger age among Arabs in Kuwait. Extensive disease at presentation is associated with younger age at diagnosis and absence of tobacco smoking. There also appears to be less need for surgery and biologic therapy for the disease in this population. [ABSTRACT FROM AUTHOR]