Lightweight concrete application in construction field is growing rapidly in these recent years due to its advantages over ordinary concrete. In this paper, pumice breccia which can be found abundantly in Indonesia is proposed to be utilized as the coarse aggregate. In spite of its benefits, lightweight concrete exhibits more brittle characteristics and lower tensile strength compared with normal concrete. On the other hand, fiber addition into concrete has become widely used to improve its tensile properties. Furthermore, the utilization of hybrid fiber in a suitable combination may potentially improve the mechanical properties of concrete. This paper experimentally examines the effects of hybrid polypropylene-steel fiber addition on some hardened properties of pumice breccia aggregate lightweight concrete. Five groups of test specimens with fixed volume fraction of polypropylene fiber combined with different amounts of steel fiber were added in concrete to investigate the density, compressive strength, modulus of elasticity, splitting tensile strength, and the modulus of rupture of the concrete mixtures. Test results indicate that hybrid fiber addition leads to significant improvement to the compressive strength, modulus of elasticity, splitting tensile strength, and the modulus of rupture of the pumice breccia lightweight aggregate concrete and meet the specification for structural purposes.

This conceptual study is a literature study. It includes various interrelated concepts which are discussed to obtain the whole idea about literati class; environment education to accustom the students’ literacy skills in primary schools. In simple perspective, literacy means the ability or competence of a person in terms of reading and writing. Recently, literacy has been viewed as an absolute need to be majored by each individual, in this case, including students in elementary school. Literacy competency in lower levels emphasizes the literacy learning more on the development of the basic foundations of students’ ability. That students’ ability is focused on the introduction of symbols, pictures or letters. Meanwhile, literacy in higher levels emphasizes on teaching students to critically analyze such as conducting interviews, observing the environment, writing reports, and doing such observations. Students could make written report, present their activity in front of the class, or display the results of their observations in the classroom. Environment education is considered as a solution to cope with literacy problem and the implant of environment care toward students earlier. Environment education is integrated in teaching and learning activity which supports the students’ literacy skills. Therefore, developing a literati class based on environment education needs enough preparation including conditioning students, the learning environment, and active participation of every component of education.

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In this research, thick film technology has been used to design and fabricate relative humidity sensors with Polyvinyl Alcohol (PVA) as the sensing layer. The design was optimized to produce an ideal geometry according to the limitations of thick film technology. The sensor fabrication process used screen printing techniques on Alumina (Al2O3) substrate with Silver (Ag) as the electrode material. SnO2 was added to the PVA sensing layer with variations in the composition of 1:1 and 1:2. FTIR analysis showed that the addition of SnO2 did not affect the structure of the PVA, which indicated that there was no chemical reaction between PVA and SnO2. The deposition of the sensing layer was carried out using spin coating method, and the fabricated sensors were then tested by varying 5 humidity points inside a chamber with a hygrometer as a reference. Based on the test results, it was found that the sensors showed responses to humidity variation in the form of changes in resistance values. When the humidity in the chamber increased, the sensor resistance value decreased. The addition of SnO2 could reduce the relatively high resistance value of the PVA-based humidity sensor and also increase the sensor's time response to humidity variation. However, the humidity sensor's sensitivity decreased for the higher composition of SnO2. With this technique, a simple yet stable humidity sensor could be fabricated using thick-film technology with a wide range of potential applications.

Objective: The development of a Self-Compacting Concrete (SCC) mixture requires a different composition compared to normal vibrated concrete. This experimental study was designed to propose a modification of the concrete mix design formula to produce an SCC mix that meets the specified requirements for both fresh and hardened concrete using Ground Calcium Carbonate (GCC) as local fine powder material. Methods: The research was carried out with a targeted compressive strength between 30 and 60 MPa. The materials that were used in this research were fine natural aggregate, crushed stone as a coarse aggregate with a maximum size of 19 mm, Portland pozzolan cement (PPC), GCC, freshwater, and high-range water reducer. The properties of fresh concrete were tested using the slump-flow test method, while the compressive strength test was carried out on 50 standard cylinders after 28 days of curing with water immersion. Results: Test results indicated that the compressive strength and fresh properties of SCC significantly depend on the water content, the water/cement ratio, the volume ratio between water to the total binder, and the weight ratio between the GCC and Portland cement. Conclusion: Furthermore, using the experimental data based on varied water content and binder compositions produces equations with a good fit for SCC mix design in the compressive strength range between 30 MPa to 60 MPa.

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Hybrid lipid polymers significantly changed the postulation of low or less bioavailability of conventional drug delivery systems. Several drug delivery systems already exist for the encapsulation and subsequent release of lipophilic drugs with enhanced therapeutic efficacy and are well described in the scientific literature. Among these, lipid polymer-based nanoparticles have specifically come up for dermal, transdermal, mucosal, intramuscular, and ocular drug administration routes in the last 20 years. Moreover, lipid nanoparticles showed potential for active targeting of anticancer therapy, delivery of DNA or RNA materials, and use as a diagnostic imaging agent. Therefore, the multifarious nanostructured lipid carriers can reduce the undesired effects with maximum utilization of active moiety. In this, chapter a brief discussion is presented on the source of synthetic and natural lipid polymers with the use of surfactants. Moreover, a summary on formulation and pharmaceutical characterization of nanostructured lipid carriers considering solid lipid nanoparticles and vesicular drug delivery systems has been taken into consideration. In addition, a light on bioactive fortified with lipid nanoparticles was reviewed for maximizing its therapeutic efficacy. Furthermore, this chapter’s focus to bring out the latest applications via recent scientific publications from the Scopus database on nanostructure carriers that showed promising application for the treatments of potentially life-threatening diseases has been summarized.

Structural performance evaluation of composite concrete slabs that were constructed using partially precast concreting system which utilized Hybrid Fiber-Reinforced Lightweight Aggregate Concrete (HyFRLWAC) as stay in-place formwork and self-compacting concrete (SCC) as topping layer was conducted in this research. This paper focused on determining the appropriate strength limit criteria of interface between two different concrete layers. The tensile strength was tested using pull-off test, while concrete cohesion was investigated based on modified bisurface shear test, and dual L-shaped shear test was used to determine the effect of normal force on the shear strength of concrete interface. Sample variants were designed based on the substrate surface conditions, compressive strength of the topping layer, and magnitude of perpendicular normal force acting on interface area. The substrate surfaces were prepared in as-placed and grooved conditions for tensile test, cohesion, and shear strength test. Test results indicate that tensile strength, cohesion, and shear strength of the concrete interface are affected by surface condition of the substrate, compressive strength of the topping layer, and the normal force acting perpendicularly on the concrete interface area. Proposed formulation for bond strength prediction between HyFRLWAC as substrate and SCC as topping layer is also presented in this paper.