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This paper aimed to determine the characteristics of physical and mechanical properties of rice straw hand sheet and investigated the optimal conditions for making rice straw paper. The chemical composition of rice straw determined with the TAPPI standards. The conditions of making paper hand sheet composed of pulping time: 2 hours, 4 hours, pulping temperature: 100°C, 130°C, pulping solvent: 2 wt% NaOH, 4 wt% NaOH and bleaching: unbleached pulp, bleached pulp with 2% H2O2. The paper hand sheet was tested based on TAPPI methods, basic weight TAPPI- T410-om-93, thickness TAPPI- T411-om-89, moisture content TAPPI- T412-om-93, brightness TAPPI T452 om-92, opacity TAPPI standard T 425 om-91, burst strength TAPPI T403 om-97, tensile strength TAPPI T494 om-01, and tear strength TAPPI-T414-om-88. The results showed that the optimal conditions of rice straw hand sheet including pulping time: 2 hours, pulping temperature: 100°C, pulping solvent: 2 wt% NaOH, and bleaching: unbleached pulp gave the highest the physical and mechanical properties form other conditions. This conditions showed as the basic weight 62.27 g/m2, thickness 259.30 µ, opacity 93.34 ISO%, burst strength 64.75 kPa.m2/g, tensile strength 95.33 N.m/g, and tear strength 473.55mN.m2/g. In this condition, the paper hand sheet used at the lowest concentration of pulping solvent and non-bleached, which reduces environmental pollution.

Anode surface plays important role for extracellular electron transfer (EET) of exoelectrogenic microbes in microbial fuel cell (MFC). In this report, the electrochemical performance of a TiO2nanorod array modified carbon paper electrode (TiO2NRs/CP) is greatly improved by controlled chemical etching process. The etching process keeps the array morphology but yields obvious hollows on tops of TiO2nanorods. The etched electrode (TiO2NRs-HOT/CP) exhibits better hydrophilicity than carbon paper (CP) and TiO2NRs/CP electrode as seen from smaller contact angle (CA) and more attached microbes S.loihica PV-4. Meanwhile, the hollows allow higher local concentration of microbial self-secreted flavins that can act as electron mediators for interfacial electron transfer of PV-4 through in-direct pathway. Accordingly, PV-4 produces larger current density at TiO2NRs-HOT/CP electrode with maximum current density of 0.038 mA cm–2, which was much higher than that at CP electrode, and almost five times higher than that at un-etched TiO2NRs/CP electrode.

Panicum repens is a species of grass known by many common names, including torpedo grass, creeping panic, panic rampant, couch panicum, wainaku grass, quack grass, dog-tooth grass, and bullet grass. The paper has been made from non-wood materials for long times. This research was used Panicum repens for made grass pulp as non-wood fiber. The influence of sodium hydroxide (NaOH) concentrations on properties of pulp from Panicum repens was investigated under room temperature. NaOH concentration levels were varied at 0%, 5%, 10%, 15%, and 20%, respectively. Moreover, Paper pulp from Panicum repens was observed by scanning electron microscope (SEM). This research has controlled the length of fiber approximately 0.5-2.5 cm before soaked with NaOH concentration at 1 hour and soak with water for controlled pH value at 7-8. Paper pulp was formed on a sieve. The result showed that color of paper pulp made from Panicum repens was light brown and green. SEM showed that NaOH concentration affects the physical properties of paper pulp. Moreover, true density of paper pulp was also investigated in this research.