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Copyright of Kemija u Industriji is the property of Croatian Society of Chemical Engineers and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The global consumption of raw materials has shifted from the use of non-renewable materials to renewable materials. Studies on greener epoxidation by using vegetable oils to produce eco-friendly epoxides have also increased. In this study, the epoxidation of palm oleic acid was carried out by in situ generated performic acid. Fourier transform infrared spectroscopy of the products was conducted to confirm the success of the epoxidation. Lastly, a mathematical model was developed using the numerical integration of the 4th order Runge–Kutta method, and the results showed good agreement between the simulation and experimental data, which validates the kinetic model. [ABSTRACT FROM AUTHOR]

The aim of the study was to identify the motivations for involvement of members of the Parumasaan rural community in Serang District in visiting Posyandu. Such studies are useful in broadening the horizons of early childhood development in rural areas in addition to disseminating the benefits for community-based early childhood education through Posyandu. Qualitative research methods are the main instrument with observation, interviews and documentation. The interviews were mainly addressed to the visitors from women. The results of the activities show that there are many Posyandu activities and programs that have an impact on the knowledge of visitors in caring for early childhood, whether received directly from the organizers or discussions with fellow mothers. Such knowledge can change people's mindset about nutrition and child development from an early age.

The purpose of this study relates to the identification of Islamic relations and national culture from Abdurrahman Wahid, a national figure who has extraordinary education and experience in the plurality of the Indonesian nation, to then analyze democracy as an important way of religion along with Indonesia's plural culture in the perspective of Maqashid Syariah. A qualitative descriptive character study relies on a basic literature review of Abdurrahman Wahid's various works, including relevant secondary sources. Everything is analyzed for its content so that it can be concluded that Islamization is a model that is not needed in the relations of Islam and national culture in Indonesia. Appreciation for the diversity of the nation is a safe gate so that the religion of Islam becomes a staple color in the nation's culture. This would not have been possible unless they put forward a just democratic life in their society. Options that do not deviate from maqashid Sharia

Copyright of Kemija u Industriji is the property of Croatian Society of Chemical Engineers and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Base isolation is a technique installed to absorb any movement or vibration on the structures. The incorporation of nanocomposites into elastomer as the interesting materials especially for the active stiffness and vibration control of structural systems. A base isolator is made up of alternate layers of steel and rubber. The performance of magnetic rubber device is dependent on mechanical and magnetic properties of composite rubber materials. A vibrating sample magnetometer (VSM) is an instrument to detect the magnetic properties. The article provides information on the magnetic properties corresponding to different carbon nanotubes loadings of 0%, 1%, 3% and 5% and different loading of microcarbonyl iron (MCI) i.e. 0% (B0), 10% (B10), 20% (B20) and 30% (B30) in natural rubber compound. The magnetic properties dataset described the data from compression test.

The growing demand for natural aggregates in the construction industry has motivated researchers to utilize recycled concrete aggregates (RCA) to preserve the natural resources and provide sustainable structure. However, the use of RCA in concrete applications has revealed defects in performance with low strength and rapid collapse under static and dynamic loads, respectively. Thus, the objective of present research is to improve these properties by using multi-walled carbon nanotubes (MWCNT). This study involves evaluating the fresh and hardened properties of recycled aggregate concrete (RAC) modified with different levels of MWCNT. The study involves RCA (i.e., 0 %, 25 %, 50 %, 75 % and 100 %) as replacement for natural aggregates, and MWCNT (i.e., 0.05 %, 0.1 % and 0.25 %) as weight of cement. The experimental testing consists of 240 specimens prepared from different mixtures. Workability is assessed using slump tests. Mechanical properties including static compressive strength and dynamic impact resistance are evaluated at 7 and 28 days. Experimental results show that incorporating MWCNT at all levels significantly reduces the slump values for all specimens. On the other hand, the compressive strength is increased by adding MWCNT to the concrete samples. The compressive strength of the RAC increased by as much as 70 % when modified with MWCNT. Furthermore, the inclusion of MWCNT is found to significantly increase the impact resistance of RAC specimens with percentage developments reaching approximately 11–508 % and 110–679 % at 7 and 28 days, respectively, at both first crack and failure stages. The dosage of 0.1 % MWCNT is shown to exhibit the highest percentage enhancement in impact resistance among the other nano levels. The failure patterns and cracks propagation are presented as well.

The use of recycled aggregates concrete (RAC) contributes effectively to reduce CO2 emissions from concrete manufacturing process while also protecting natural resources by utilizing existing available concrete as an aggregates source for a new one. Studies on the behaviour of RAC have revealed negative effects on concrete strength and microstructure development, resulting in deterioration of mechanical and durability properties. As a result, numerous practical studies have been implemented to enhance the RAC properties using various treatment techniques such as chemical, physical and heating treatments. However, most of these techniques are ineffective compared to conventional concrete applications due to poor mechanical performance of RAC, insufficient environmental requirements, and prolonged treatment times. Recently, the use of nanomaterials has been given significant concern in RAC research. Their nano-sized particles can help to reduce micropores formation by acting as a filling agent to produce a high-density microstructure, thereby enhancing the mechanical properties and durability of RAC. This had led to a wide range of studies being published on improving RAC properties by using nanomaterials. However, relatively few literatures had been conducted on the effects of different types of nanomaterials on the performance of RAC exposed to various types of loads and various external environmental impacts. Besides, the conditions used by authors in these literatures limit comparisons, and in some cases contradictory findings are observed. Thus, this paper aims to bridge the knowledge gap between researchers. This would allow the potential of nanotechnology in innovations to be applied in appropriate areas of RAC applications to benefit the general public good. This paper aims to provide a critical review and comprehensive conclusions on the performance of nano-modified RAC under external loads, environmental impacts and other various conditions. The effects of nanomaterials on the compressive, tensile, and flexural strength of RAC are discussed. The nanomaterials considered are nano-SiO2, nano-CaCO3, nano-TiO2, nano-Clay, nano-Al2O3, and nano-Carbon. Durability characteristics including water absorption, chloride penetration, fire exposure, abrasion resistance, acid and carbonation diffusions are extensively discussed. Microstructure characteristics using SEM, XRD, EDS, and micro-hardness of nano-modified RAC are addressed as well.