Why do greater forest tenure rights not enthuse local communities? An early observation on the new community forestry scheme in state forests in Indonesia

The Indonesian Ministry of Environment and Forestry recently issued a 35-year permit-based social forestry, called Izin Pemanfaatan Hutan Perhutanan Sosial (IPHPS), which was implemented in forestlands managed by the State Forest Corporation (SFC). IPHPS is a unique scheme because social forestry permits were previously granted on forestland unencumbered with rights. It provides more secure tenure rights (long-term permits), greater decision-making authority, and improved profit-sharing arrangements compared with the SFC’s co-management model. However, IPHPS has not attracted widespread interest from local communities. This paper aims to identify and to analyse factors that explain local communities’ low interest in the policy. Results show that local communities have not been attracted by the scheme because it requires them to undertake substantial investments in reforestation and make several payments to the government beyond their means. This paper highlights the specific challenges related to access mechanisms and benefits to local communities from the granted rights. Lastly, local communities were prone to manipulative persuasion by the SFC to continue the co-management model

Physicochemical characteristics of recycled tyre tread compounds

The present work was aimed at evaluating the physicochemical characteristics of seven recycled tyre tread compounds. The materials were characterized for elemental composition, surface morphology, surface chemistry, oil content, ash content, thermal degradation and dielectric properties. Some of the materials were analyzed according to the Rubber Research Institute Malaysia (RRIM) in-house methods for comparison. Natural rubber, butadiene rubber and styrene-butadiene rubber were also employed to validate the thermal degradation profile. Results show that all materials exhibit comparable elemental composition, and dielectric and surface properties, but dissimilar composition of rubber compounds as revealed by the simple mass balance-thermogravimetric approach. The finding is consistent with the RRIM in-house methods. The proposed thermogravimetric approach is sufficient to assess the composition and quality of recycled tyre tread compounds

Influence of Rubber Content on Mechanical, Thermal, and Morphological Behavior of Natural Rubber Toughened Poly(Lactic Acid)-Multiwalled Carbon Nanotube Nanocomposites

The effects of natural rubber (NR) on the mechanical, thermal, and morphological properties of multiwalled carbon nanotube (CNT) reinforced poly(lactic acid) (PLA) nanocomposites prepared by melt blending were investigated. A PLA/NR blend and PLA/CNT nanocomposites were also produced for comparison. The tensile strength and Young's modulus of PLA/CNT nanocomposites improved significantly, whereas the impact strength decreased compared to neat PLA. The incorporation of NR into PLA/CNT significantly improved the impact strength and elongation at break of the nanocomposites, which showed approximately 200% and 850% increases at 20 wt % NR, respectively. However, the tensile strength and Young's modulus of PLA/NR/CNT nanocomposites decreased compared to PLA/CNT nanocomposites. The morphology analysis showed the homogeneous dispersion of NR particles in PLA/NR/CNT nanocomposites, while CNTs preferentially reside in the NR phase rather than the PLA matrix. In addition, the incorporation of NR into PLA/CNT lowered the thermal stability and glass-transition temperature of the nanocomposites

Solubility assessment of castor (Ricinus communis L) oil in supercritical CO<inf>2</inf> at different temperatures and pressures under dynamic conditions

A simple dynamic technique was used to obtain the solubility of castor oil in supercritical carbon dioxide. The solubility was measured at temperatures ranging from 313 to 335K and pressures from 20 to 36MPa. Under extraction conditions, the measured solubilities were in the range from 1.29×10-3 to 4.88×10-3 (g of oil)/(g of CO2). Measurements confirmed that temperature and pressure have direct effects on solubility-enhancement factors. Five semi-empirical models were tested for their ability to correlate experimental data: the Chrastil, Del Valle Aguilera (VA), Bartle, Kumar and Johnston (KJ), and Mendez-Santiago and Teja (MST) models. Over the temperature and pressure ranges studied, solubilities from these models had the following average absolute relative deviations from experimental data: Chrastil, VA, Bartle, KJ and MST models with an average absolute relative deviation percent (AARD%) of 0.05%, 0.30%, 0.38%, 5.98% and 28.4%, respectively. Thus, the Chrastil, VA and Bartle models correlated the castor oil solubility data with the lowest AARD%

Acid Hydrolysis and Optimization Techniques for Nanoparticles Preparation: Current Review

Nanostarch is unique in that it is highly soluble, thermally stable, non-toxic and inex�pensive. Hence, it is utilized in numerous well-established applications, including drug delivery, cosmetics, textiles, foods, and enhanced oil recovery (EOR). These applications take advantage of the special functions that can be achieved through modifcations to the structure and properties of native starch. The most common method for the preparation of nanostarch with a relatively higher crystallinity and stability is acid hydrolysis. Technically, the properties of nanostarch are highly dependent on several factors during the hydrolysis process, such as the acid, concentration of acid, reaction time, reaction temperature, and source of starch. The production of nanostarch with desired properties requires a detailed understanding on each of the factors as they are inevitably afected the physical and chemi�cal properties of nanostarch. Hence, it is vital to incorporate optimization technique into the production process to achieve the full potential of nanostarch. Therefore, the current review comprehensively elaborates on the factors that afect acid hydrolysis as well as the optimization techniques used in the preparation of nanostarch

The chemistry insight: epoxy sealant as an alternative remedial operation for well integrity

Epoxy resin is commonly used in the oil and gas industry due to its excellent toughness, low shrinkage, good adhesive strength, and relatively good thermal resistance. It is used for water shutoff, zonal isolation, cementing, enhanced oil recovery, and preventing leakage in wells. This paper reviews the chemistry aspect of using an epoxy resin system as a sealant to prevent well leakage and it offers insights into the chemistry of the epoxy resin system, as applied in previous studies. The paper also unveils the reasons for the application of this system from the chemistry perspective, allowing this aspect to be better understood. Success in the investigated cases depended on the formulation design. The epoxide and hydroxyl func�tional groups have been found to contribute substantially to the excellent performance of the sealant system. Furthermore, the amine curing agent triggers the abrupt reaction of the oxirane ring to stabilise when the cured sealant is perfectly applied. Based on the findings, it is suggested that other types of epoxies, namely epoxidised oils, require further study. Finally, in terms of safety an

Minimum CO2 Miscibility Pressure Evaluation using Interfacial Tension (IFT) and Slim-tube Hybrid Tests

The effectiveness of CO2-enhanced oil recovery (EOR) is strongly dependent on the CO2−oil minimum miscible pressure (MMP) value, which can be estimated using various methods. In this study, interfacial tension (IFT) and slim-tube tests were used to estimate the MMP value. Experimental results indicated that the IFT test had a higher MMP value than the slim-tube test. Particularly, the outcomes of IFT and the slim-tube tests differed slightly, i.e., 0.7% and 4.3% at 60 and 66 °C, respectively. Furthermore, the current work also compares MMP data gathered using visual observation and equation of state (EOS) simulation. The MMP estimated by EOS is higher but close to the IFT and slim-tube recovery factor method, where all results are within the 1650− 1700 psi and 1700−1800 psi visual observation ranges at 60 and 66 °C, respectively. However, MMP deviations concerning the slim-tube test and EOS were consistent at different temperatures. This study offers an alternative to estimate and evaluate CO2−oil MMP for EOR applications accurately and efficiently

A survey on industry 4.0 for the oil and gas industry: upstream sector

The market volatility in the oil and gas (O&G) sector, the dwindling demand for oil due to the impact of COVID-19, and the push for alternative greener energy are driving the need for innovation and digitization in the O&G industry. This has attracted research interest from academia and the industry in the application of industry 4.0 (I4.0) technologies in the O&G sector. The application of some of these I4.0 technologies has been presented in the literature, but the domain still lacks a comprehensive survey of the application of I4.0 in the O&G upstream sector. This paper investigates the state-of-the-art efforts directed toward I4.0 technologies in the O&G upstream sector. To achieve this, first, an overview of the I4.0 is discussed followed by a systematic literature review from an integrative perspective for publications between 2012-2021 with 223 analyzed documents. The benefits and challenges of the adoption of I4.0 have been identified. Moreover, the paper adds value by proposing a framework for the implementation of I4.0 in the O&G upstream sector. Finally, future directions and research opportunities such as framework, edge computing, quantum computing, communication technologies, standardization, and innovative areas related to the implementation of I4.0 in the upstream sector are presented. The findings from this review show that I4.0 technologies are currently being explored and deployed for various aspects of the upstream sector. However, some of the I4.0 technologies like additive manufacturing and virtual reality are least explored

Compatibiliser effects on properties of polyamide-6/acrylonitrile-butadiene-styrene and polyamide-6/acrylonitrile-butadiene-styrene/short glass fibrethermoplastic composite

Polyamide-6 (PA6), acrylonitrile-butadiene-styrene (ABS) and their blends are an important class of engineering thermoplastics that are widely used in electronic and automotive industries. Many efforts have been taken to improve the properties of both pure components and the blends. It was for this reason that the dynamic mechanical and rheological properties of PA6/ABS blend systems compatibilised by acrylonitrile-butadiene-styrene–maleic anhydride (ABS-g-MAH) was studied. The compatibiliser levels were kept up to 5wt. % in the blends. Short glass fibre (SGF) was used to improve the stiffness of the compatibilised blends and the fibre contents were from 10 to 30 wt. %. Therefore, the reason behind blending the PA6/ABS blends with short glass fibre was to balance the toughness and stiffness. Both the blends and corresponding composites were compounded using a counter-rotating twin screw extruder. Tensile, flexural and impact properties were determined using the injection moulded test samples according to ASTM standards. The mechanical properties of the blends and the composites were investigated in both static and dynamic modes. Rheological properties were investigated using rotational and capillary rheometer. In general, the mechanical strength either dynamic (refer to dynamic mechanical properties) or static conditions improved by incorporation of compatibiliser to the PA6/ABS blends. The incorporation of SGF into the PA6/ABS blends enhanced the mechanical strength but reduced the toughness of the composites. The rheological measurements confirmed the interaction between the blend components with the incorporation of compatibiliser has been improved. However, the compatibiliser has no favourable effect on the mechanical properties of the composites although it has significant effect on the blends of PA6/ABS. The compatibiliser increased the melt viscosity of the blends. The SGF increased the rheological properties especially viscosity and flowability of the composites. The optimum ratio of compatibiliser and SGF concentration were determined using power law, n and consistency index, K analyses. From the analysis, the optimum ratio obtained was 1.5 wt. % for 50/50 and 60/40 PA6/ABS blends and 3 wt. % for 70/30 PA6/ABS blends. The n values drastically decreased, when concentration of the SGF was about 20 wt % indicating more pseudoplastic nature for the composites and suggesting that, 20 wt % is the optimum SGF concentratio