The present study deals with the sound absorption performance of natural fibres from the oil palm frond (OPF), mainly considered agricultural waste. Therefore, this study aimed to investigate the sound absorption performance of OPF fibre-reinforced composite under normal incidence sound. The materials used were OPF particles and urea-formaldehyde was used as an adhesive. The particleboards were produced with three particle sizes and four target densities. The absorption coefficient of normal incidence sound (α_n) was tested using an impedance tube. The effects of particle size and bulk density were also evaluated. The findings reveal thatα_n exceeded 0.45 at 1000 Hz and could reach 0.95 above 3.3 kHz. This occurred when the bulk density of the OPF composite particleboards ranged between 0.3–0.4 g/cm³, and the particle size varied between medium to coarse. The results also indicated that the absorption frequency and the degree of α_n significantly increased as the bulk density decreased. Therefore, OPF fibres can be used to create sound-absorbing composite particleboards.

Co-pyrolysis is a thermochemical process using more than one raw material to become a new energy source without oxygen at high or low temperatures. This study aims to determine the effect of co-pyrolysis if temperature and residence time are varied on the yield of bio-oil mixed with biomass and medical waste. The research was conducted using a small-scale batch reactor equipped with an electrically controlled band heater as a reactor tube heater. Co-pyrolysis was carried out with variations in temperature, namely 300°C, 400°C, and 500°C, as well as three different raw material waiting times in the reactor, namely 10, 15, and 20 minutes. The flow rate of nitrogen gas to the reactor is set at 0.5 liters per minute, and the number of samples taken for each batch procedure is 60 grams. The results showed that increasing the temperature positively affected bio-oil yield, but applying very high temperatures had the opposite effect, namely decreasing the amount of bio-oil but increasing the amount of syn-gas produced. Residence time dramatically affects the composition of the bio-oil and syn-gas compounds produced but does not significantly affect the biochar yield. At lower and moderate temperatures, prolonging the residence time enhances bio-oil production. However, at 500°C, extending the residence time diminishes bio-oil yield. The bio-oil obtained has a high calorific value of 46.334 MJ/kg, making it suitable for use as an alternative fuel.

Characterization of the Mechanical Properties of Fiberglass/Epoxy Prepreg Composites as Horizontal Axis Wind Turbine Blade Material: Influence of Fiber Orientation on Impact and Bending Strength

The quest for innovative, eco-friendly materials has spurred the exploration of agricultural biomass waste as a potential resource for polymer composites. The current study examines the impact of untreated oil palm frond (OPF) fiber on the multifunctional and sustainable performance of rigid polyurethane (PU) foam in the oil palm industry, in alignment with Sustainable Development Goals 12 and 13. Using a one-shot polymerization method, OPF foams were fabricated with fiber contents of 0, 5, 10, 20, and 30 (wt%). The foams were tested for density, morphology, compressive strength, and sound absorption performance in accordance with ASTM D1621 and ISO 10534-2. Experimental densities were compared with theoretical values to confirm that the foam production process was consistent. Scanning electron microscopy analysis revealed that OPF contents above 20 wt% disrupted the cellular structure, resulting in non-uniform cell sizes and increased cell wall collapse. These morphological defects contributed to a reduction in compressive strength from 0.1901 N/mm² for neat PU foam to 0.0697 N/mm² at 30 wt% OPF. In contrast, the 30 wt% OPF foam showed greater porosity and a higher proportion of open cells, resulting in superior sound absorption performance in the 1000–2500 Hz frequency range. Overall, the findings reveal a clear trade-off between mechanical strength and acoustic efficiency. PU foams with high OPF content possess eco-sustainable benefits and enhanced sound-absorbing qualities. Despite the reduction in compressive strength, high OPF-loaded PU foams show potential for lightweight, non-structural applications, such as automotive parts and interior building materials.

Perencanaan operasional yang tepat perlu dilakukan untuk meningkatkan efektifitas kerja PLTU Tanjung Balai Karimun karena berpengaruh langsung pada biaya operasional yang dikeluarkan oleh perusahaan. Performance setiap peralatan utama di PLTU khususnya Boiler perlu menjadi perhatian karena dari nilai efesiensi ini dapat dilihat langsung apakah sebuah pembangkit dapat dikatakan layak atau tidak untuk beroperasi. Semakin tinggi nilai efesiensi dari sebuah boiler maka unjuk kerjanya di lapangan juga bagus. Tujuan penelitian ini adalah Menghitung performance boiler dengan metode tidak langsung sesuai standar ASME PTC-4-1 Power Test Code Steam Generating Units sehingga dapat mengetahui neraca bahan dan energi yang lengkap untuk setiap aliran, yang dapat memudahkan dalam mengidentifikasi opsi-opsi untuk meningkatkan efisiensi boiler dan untuk memudahkan perhitungan efesiensi boiler dibuat software perhitungan yang dibangun berbasis macromedia flash. Dengan memasukkan data yang diambil langsung dari hasil pengujian performance di PLTU Tanjung Balai Karimun dihasilkan efisiensi boiler sebesar 82,7 %, dan Hasil perhitungan menggunakan aplikasi simulasi perhitungan ditemukan losses pada gas buang sebesar 5,14 %, loosses pada hidrogen in fuel sebesar 5,34 %, losses akibat moisture in fuel sebesar 5,47 %, losses pada moisture in air sebesar 0,21 %, losses akibat pembakaran tidak sempurna sebesar 0,07 %, losses akibat radiasi dan konveksi sebesar 1,05 % dan losses akibat batu bara tidak terbakar pada fly ash sebesar 0,00008% dan losses akibat batu bara tidak terbakar pada bottom ash sebesar 0,00021%

Jumlah angkatan kerja di Riau pada Februari 2015 mencapai 2.974.014 orang, atau naik 172,849 orang (6,17 persen) dibandingkan jumlah angkatan kerja pada Februari 2014 sebesar 2.801.165 orang. Jumlah penduduk yang bekerja di Riau pada Februari 2015 sebesar 2,774,245 orang atau bertambah 112,918 orang (4,2 persen) dibandingkan dengan keadaan pada Februari 2014. Tingkat pengangguran terbuka pada Februari 2015 sebesar 6,72 persen, lebih tinggi dibandingkan keadaan pada Februari 2014 (4,99 persen). Sebagian besar para remaja putus sekolah usia produktif tidak memiliki keterampilan berwirausaha sehingga tidak bisa mendapatkan atau menciptakan lapangan kerja. Jumlah bengkel las di kecamatan Sukajadi khususnya kelurahan sukajadi relatif masih kurang dibandingkan dengan jumlah pengguna jasa las. Masih kurangnya pembinaan terhadap Sebagian besar Para remaja putus sekolah usia produktif untuk mendapatkan/menciptakan lapangan pekerjaan khususnya dibidang teknik pengelasan. Teknik mesin fakultas teknik UMRI,menyelenggarakan pengabdian dalam bentuk kegiatan pelatihan keterampilan las pada remaja putus sekolah usia produktif di kelurahan Sukajadi Kecamatan Sukajadi kota Pekanbaru , pelatihan dilaksanakan selama lima hari dengan jumlah peserta 10 orang. Para peserta secara langsung praktek dibawah bimbingan dan pengawasan pelaksana pelatihan yang bertindak sebagai instruktur. Metode demontrasi dan peragaan ini sangat efektif untuk pelatihan las , peserta pelatihan menerapkan modul yang telah didiskusikan dengan tim pelaksana, secara langsung pada peralatan las yang telah disiapkan oleh panitia.