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"The production and/or worldwide consumption of chicken at an industrial or domestic level lead to a considerable quantity of chicken feather residue as a waste by-product. Chicken feathers have a possible application in preparing lightweight composites. The use of chicken feathers as a constituent to prepare hybrid composites leads to a solution for disposal of the feathers. In this study, chicken feathers were used as filler material to prepare hybrid composites. Different varieties of composites were prepared by a chicken feather hand-layup technique, and by varying the percentage weight of the chicken feathers. Specimens were prepared and tested according to ASTM standards. The 10 wt. % chicken feather-filled hybrid composites indicated the maximum tensile strength (193 MPa), flexural strength (148 MPa) and impact strength (3.65 Joules). Scanning Electron Microscopy (SEM) analysis was carried out to find the fracture and interfacial characteristics of the composites. The results indicated that, these composites can be used in domestic, automobile and structural applications which carry nominal loads."

"Penggunaan komposit sandwich dalam berbagai aspek kehidupan semakin meningkat belakangan ini. Komposit sandwich banyak digunakan karena mempunyai rasio modulus terhadap berat yang tinggi, rasio kekuatan terhadap berat yang tinggi, ketahanan aus, hingga ketahanan terhadap korosi. Penelitian ini bertujuan untuk membandingkan pengaruh teknik fabrikasi yang digunakan terhadap sifat mekanik komposit sandwich. Komposit sandwich dibuat dari serat gelas anyam dan resin poliester tak-jenuh sebagai kulit dan busa poliuretan kaku sebagai inti menggunakan dua teknik fabrikasi yakni adhesive-cold press dan Vacuum Assisted Resin Infusion (VARI). Pada komposit sandwich kemudian dilakukan uji tarik, uji tekan, uji lentur, dan uji densitas. Untuk komposit sandwich yang difabrikasi dengan teknik adhesive-cold press, didapatkan nilai kuat tarik, kuat tekan, kuat lentur dan densitas berturut-turut sebesar (1,55 ± 0,01) MPa, (1,30 ± 0,01) MPa, (11,04 ± 0,45) MPa, dan (0,29 ± 0,01) g/cm3. Sementara itu, untuk komposit sandwich yang difabrikasi dengan teknik VARI, didapatkan nilai kuat tarik, kuat tekan, kuat lentur dan densitas berturut-turut sebesar (2,25 ± 0,42) MPa, (1,41 ± 0,01) MPa, (13,84 ± 0,42) MPa, dan (0,33 ± 0,01) g/cm3. Hasil ini menunjukkan bahwa sifat mekanik dari komposit sandwich yang difabrikasi dengan teknik VARI lebih tinggi dari pada yang difabrikasi dengan teknik adhesive-cold press. Tidak ada perbedaan mode kegagalan yang terjadi pada kedua tipe komposit sandwich. Untuk uji tarik dan tekan, mode kegagalan yang terjadi adalah kerusakan inti busa, sedangkan untuk uji lentur adalah kerusakan kulit bagian atas. Hal ini menunjukkan bahwa ikatan inti dan kulit dengan kedua teknik sangat baik.

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The use of sandwich composites in various aspects of life has increased lately. Sandwich composites are widely used because of their high modulus-to-weight ratio, high strength-to-weight ratio, wear resistance, and corrosion resistance. This study aimed to compare the effect of the fabrication techniques used on the mechanical properties of sandwich composites. The sandwich composites were fabricated from woven glass fiber reinforced unsaturated polyester resin as skin and rigid polyurethane foam as core using two fabrication techniques, namely adhesive-cold press and Vacuum Assisted Resin Infusion (VARI). The sandwich composites were then tested for tensile, compressive, flexural, and density tests. For the adhesive-cold pressed sandwich composites, the values of tensile strength, compressive strength, flexural strength, and density were (1.55 ± 0.01) MPa, (1.30 ± 0.01) MPa, (11.04 ± 0.45) MPa, and (0.29 ± 0.01) g/cm3, respectively. Meanwhile, for the VARI fabricated sandwich composites, the values of tensile strength, compressive strength, flexural strength, and density were (2.25 ± 0.42) MPa, (1.41 ± 0.01) MPa, (13,84 ± 0.42) MPa, and (0.33 ± 0.01) g/cm3, respectively. These results indicated that the mechanical properties of sandwich composites fabricated with the VARI technique were higher than those fabricated with the adhesive-cold press technique. For the tensile and compressive tests, the failure mode was foam core failure, while for the flexural test was upper skin failure. These results indicated that the bonding of the core and skin with both techniques is excellent."

"Menyongsong era pasar bebas terutama di Asia Tenggara pada tahun 2003, mendorong pimpinan perusahaan mengambil langkah-langkah penting ke depan untuk meningkatkan kualitas produk serta nama baik perusahaannya masing-masing. Perhatian publik (masyarakat, pemerintah, badan usaha, investor) saat ini tidak hanya terpaku pada mutu produk tetapi juga bagaimana produk tersebut diproses dari awal hingga akhir. Tujuan penelitian yang dilakukan mulai 17 September hingga awal Desember 1999 pada PT Gunung Putri Graha Mas, selaku produsen fiberglass reinforced & composite plastik, adalah untuk meningkatkan efisiensi produksi dengan metode pencegahan pencemaran (pollution prevention). Berdasarkan pengamatan langsung di pabrik, keterangan pihak perusahaan, bimbingan dosen, serta studi literatur didapatkan hasil bahwa sebagian besar produksi telah berjalan dengan baik. Walaupun demikian masih terdapat kekurangan pada bidang pengecatan (spraying), penggunaan bahan baku, kontrol polusi udara, hasil akhir, penanganan limbah, dan kondisi lingkungan kerja. Untuk meningkatkan efisiensi melalui program pencegahan pencemaran pada bidang-bidang di atas, dapat dilakukan antara lain : penggantian spray gun menjadi Airless spray gun, substitusi acetone dengan dibasic ester, perbaikan prosedur dan teknik kerja, penambahan blower baru, penanganan limbah secara benar, dan perbaikan kondisi lingkungan kerja. Diharapkan dengan program pencegahan pencemaran ini akan memberikan dampak positif kepada perusahaan sehingga industri fiberglass sekarang menjadi industri berwawasan lingkungan."

"Komposit sandwich merupakan komposit struktur yang diproduksi menjadi panel atau balok ringan yang memiliki sifat kekakuan dan kekuatan yang tinggi. Penelitian ini bertujuan untuk membandingkan sifat mekanik dan morfologi komposit sandwich kulit polyester berpenguat woven roving E glass dan inti honeycomb polypropylene yang difabrikasikan dengan teknik VARI dan adhesif cold-press. Pengujian mekanik yang dilakukan pada penelitian ini adalah uji lentur, uji tarik, dan uji tekan. Pengamatan morfologi pada sebelum dan sesudah pengujian dilakukan dengan menggunakan kamera. Hasil penelitian ini menunjukkan bahwa fabrikasi adhesif cold-press memiliki nilai kekuatan lentur, tarik, dan tekan yang lebih unggul dibandingkan dengan metode VARI yaitu masing-masing sebesar (24,93 ± 0,21) MPa, (0,52 ± 0,02) MPa, dan (1,95 ± 0,05) MPa. Setelah uji lentur, tarik, dan tekan, sampel mengalami kerusakan pada bagian inti.

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Sandwich composites are structural composites that are manufactured into lightweight panels or beams with high stiffness and strength properties. This study aimed to compare the mechanical properties and morphological of polyester skin sandwich reinforced with woven roving E-glass reinforced polyester as skins and a polypropylene honeycomb core fabricated by the VARI and cold-press adhesive techniques. The mechanical tests which were flexural, tensile, and compressive tests were conducted. Morphological observations before and after testing were carried out using a camera. The results of this study indicated that the cold-press adhesive fabrication had superior flexural, tensile, and compressive strength values compared to the ones of VARI method, namely (24,93 ± 0,21) MPa, (0,52 ± 0,02) MPa, and (1,95 ± 0,05) MPa respectively. After bending, tensile, and compressive tests, all samples were failed in the core."

"ABSTRAKKonsep Industri Hijau berawal dari konsep efisiensi dan efektivitas, yang awalnya menjadi daya saing industri. Konsep ini kemudian berkembang menjadi konsep berkelanjutan sustainability , produksi bersih cleaner production , dan dengan memasukkan unsur lingkungan dan sosial masyarakat kemudian menjadi konsep industri hijau green industry . Dikarenakan beragamnya persepsi terkait industri hijau, dibuatlah Standar Industri Hijau SIH . SIH disusun berdasarkan konsensus antar perwakilan pemerintah, industri, asosiasi, stake holder terkait dan difasilitatori akademisi. Sehingga terdapat standar berupa kesepakatan bersama yang tentunya berbeda dengan negara lain. Penyusunan SIH dilakukan secara bertahap sesuai prioritas industrinya. Namun untuk kasus SIH Industri Kaca Lembaran IKL , perumusannya minim akan kajian akademis. Sehingga hal tersebut menjadi salah satu faktor yang mendasari dilakukannya penelitian ini. SIH tersebut dapat berkembang dan ditinjau di kemudian hari. Maka, dalam penelitian ini, SIH keluaran Kemenperin RI menjadi suatu bahasan yang ditinjau untuk mendapatkan level ketetatannya dibandingkan negara lain dan sebagai masukan saat peninjauan nantinya. Selanjutnya, dilakukan studi kasus penerapan SIH IKL Kemenperin RI pada PT. X dengan melakukan evaluasi capaiannya dan strategi untuk mencapai SIH tersebut. Hasil penelitian yang diperoleh adalah, pertama, terdapat 7 faktor yang mendasari pentingnya SIH bagi IKL. Faktor teknisnya yaitu: konsumsi energi, emisi, dan efisiensi produksi, dengan faktor yang paling dominan adalah efisiensi produksi. Sedangkan untuk faktor nonteknis yaitu: skala industri, nilai ekspor, sumbangsih terhadap PDB, dan Market Demand, dengan faktor yang paling signifikan adalah Market Demand. Kedua, level ketetatan SIH IKL Kemenperin adalah 0,53. Sehingga terdapat peluang untuk pengetatan. Ketiga, hasil evaluasi menunjukkan PT. X belum comply terhadap SIH IKL Kemenperin. Aspek yang tidak terpenuhi adalah RPB 81 dengan standar minimum 81,5 dan penggunaan energi listrik 1,18 GJ/ton dengan standar maksimum 0,7 GJ/ton. Sedangkan untuk penggunaan energi panas, air make-up, emisi, dan OEE sudah memenuhi SIH. Namun masih terdapat peluang untuk improvisasi. Keempat, dari hasil analisis kondisi aktual, terdapat 10 strategi yang diusulkan kepada PT. X, dari hasil kuesioner AHP dipilihlah strategi mempertahankan B/C ratio pada 75/25 dan melakukan strategi heat recovery pada flue gas keluaran furnace dengan mengaplikasikan boiler tube pada bottom regenerator. Dimana peluang recovery panasnya adalah 25-30 .Keyword : Standar Industri Hijau, Industri Kaca Lembaran, efektivitas, efisiensi, berkelanjutan

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ABSTRACTThe Green Industry Concept originated from the concept of efficiency and effectiveness, which initially became industry competitiveness. This concept then evolves into sustainability, cleaner production, and by incorporating environmental and social elements into a green industry concept. Due to the variety of the perceptions about green industry, a Green Industry Standard GIS was created. GIS is compiled based on consensus among government representatives, industries, association, stakeholders and facilitated by academics. So there are standards of mutual agreement which is certainly different from other countries. The preparation of GIS is done gradually according to the priority of the industry. But for the case of GIS for Flat Glass Industry FGI , its formulation was lack of academic studies. So it becomes one of the factors that underlie this research. The GIS may develop and be reviewed in the future. Thus, in this study, the GIS from Ministry of Industry of RI became a reviewed subject to get its stringent level compared to other countries and as the recommendations later. Furthermore, GIS of FGI from Kemenperin RI implementation at PT. X by evaluating its achievements and strategies to achieve the GIS became the case study. The results of the research are, first, there are 7 factors underlying the importance of GIS for FGI. The technical factors are energy consumption, emissions, and production efficiency, with the most dominant factor is production efficiency. While for nontechnical factors are industrial scale, export value, contribution to GDP, and Market Demand, with the most significant factor is Market Demand. Second, the stringent level of GIS FGI from Kemenperin is 0.53. So there is an opportunity for tightening. Third, the evaluation results show that PT. X especially F2 is not complying with GIS FGI from Kemenperin. Unfulfilled aspect is RPB 81 with minimum standard 81.5 , and electricity consumption is 1.18 GJ ton with maximum standard 0.7 GJ ton. As for the use of heat energy, make up water, CO2 emission, and OEE already meet the GIS. But there are still opportunities for improvisation. Fourth, there are 10 strategies proposed to PT. X F2, the results of the AHP questionnaire were chosen to maintain the B C ratio at 75 25 and to perform a heat recovery strategy on the flue gas of furnace output by applying the boiler tube to the bottom regenerator. Where is the heat recovery opportunities are 25 30 .Keyword Green Industry Standard, Flat Glass Industry, effectiveness, efficiency, sustainability"

"ABSTRAKBambu sebagai salah satu serat alam yang ada di Indonesia berpotensi menjadi penguat pada komposit yang ramah lingkungan. Penelitian ini dilakukan untuk menentukan jenis komposit dan kuat lengkung dari komposit polipropilena/serat Bambu Tali (PP/SBT) sesuai dengan SNI 01-4449-2006 untuk papan serat dan kekeraannya. Serat Bambu Tali diberi perlakuan alkali sebelum dijadikan penguat komposit. Single Fiber Test dan analisa FTIR dilakukan pada serat Bambu Tali sebelum dan sesudah proses alkalisasi. Fabrikasi komposit menggunakan mesin ekstruder dengan variasi fraksi berat serat Bambu Tali 10wt%, 20wt%, dan 30wt%, dengan ukuran serat 0.5 mm. Uji lengkung dan kekerasan dilakukan pada komposit dan polipropilena murni, dan pengamatan Scanning Electron Microscope (SEM) dilakukan pada permukaan patahan uji lengkung. Hasil uji lengkung dan densitas menunjukkan bahwa komposit PP/SBT merupakan tipe Papan Serat Kerapatan Tinggi (PSKT) T1, dengan modulus lengkung dan kuat lengkung terbaik pada PP/SBT 30wt% masing-masing yaitu (79,01±4,47) GPa dan (36,97±3,03) MPa. Nilai ini meningkat 15,5% dan 25,6% dari polipropilena murni. Nilai uji kekerasan terbaik pada komposit PP/SBT 30wt% yaitu (61,86±0,67) HD yang meningkat 26% dari nilai kekerasan polipropilena murni. Hasil pengamatan SEM terlihat patahan serat terjadi pada permukaan patahan uji lengkung.

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ABSTRACT

Bamboo as one of the natural fibers in Indonesia has the potential to become an environmental friendly composite reinforcement. This study was conducted to determine the density of composite and bending properties of polypropylene/Tali Bamboo fiber (PP/TBF) composites in accordance with SNI 01-4449-2006 for fiberboard and their hardness. Tali Bamboo Fiber was treated with alkali before being fabricated. Single Fiber Test and FTIR analysis were conducted on Tali Bamboo fibers before and after the alkalization process. Composites were fabricated using an extruder machine with variations in the weight fraction of Tali Bamboo fiber i.e 10wt%, 20wt%, and 30wt%, with a fiber size of 0.5 mm. Bending and hardness tests were carried for composites and pristine polypropylene ; fracture surfaces after bending test were ensured using Scanning Electron Microscope (SEM). The density and bending test results showed that all PP/TBF composites were categorized as Papan Serat Kerapatan Tinggi (PSKT) T1 type. PP/TBF30 composites had the highest bending modulus and strength of (79.01±4.47) GPa and (36.97±3.03) MPa respectively. These values increased 15.5% and 25.6% compared to the pristine polypropylene. The highest hardness value belong to PP/TBF30 i.e (61,86±0.67) HD, in which increased 26% from the value of pristine polypropylene hardness. SEM observations showed that fiber failure occurred on the fracture surfaces after bending test.

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"The traditional fiber reinforced composite (FRC) contains bishpenol A glycidyl methacrylate (bis-GMA) in the resin matrix, which is thought to have some disadvantages. This research aimed at replacing bis-GMA with another monomer-urethane dimethacrylate (UED-MA), with the desired properties for dental use still retained. Four groups were prepared with light-curing (n = 30), one Control group with a bis-GMA-based resin matrix and three experimental groups with UEDMA-based matrices (Exper 1, Exper 2 and Exper 3 with a varying UEDMA weight percentage). Specimens were stored in dry conditions for 24 h or in deionized water for 1, 3, 6 or 12 months prior to the tests. Water sorption (n = 6), Vicker's hardness (n = 6) and flexural properties (n = 6) after each storage time were investigated.Scanning electron microscopy (SEM) images were taken at the fracture sites after 3-point bending. All the results were statistically analyzed (α = 0.05). The Exper 1 group exhibited the lowest weight increase after water storage among the experimental groups. As for dry conditions, 1- and 6-month storage, different resin matrix compositions made no significant difference to hardness, while for 3- and 12- month storage, "Control" possessed the highest hardness. The Control group's strength and modulus, Exper 1 and Exper 2's modulus were stable during water storage. Compared to other experimental groups, Exper 1 had the highest strength and modulus values with most of the storage times. SEM images showed relatively good adhesion between the fiber and the matrix. With all the tested properties considered, the Exper 1 group had superior performance among all the three experimental groups."

"Design couch spect gamma camera. Design has been carried out couch spect gamma camera. This plan aims to complement the patient's bed gamma camera of fiber glass materials. Methods of making fiber by fiber glass casting. The shape of the bed made curved in the middle to add strength. From the result of design gain is expected to be on the couch spect gamma camera is made of fiber glass."