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"ABSTRAKScope and Research method : In order to find out the prevalence rate of respiratory obstruction due to exposure to jute's dust and other risk factors, such as work place, age group, length of work, smoking habit, usage of personal protection device, clinical symptom and allergy history, a cross sectional study regarding the influence of jute's dust on lung function among jute factory worker has been done in Tangerang. Total sample of respondent for this study is 135 workers, who are working in 4 working unit in the factory. There are 4 methods of data collection used in this study. First, interview by using Pneumomobile Project Indonesia questioner. Second, physical examination to all employees especially related to respiratory disorder. Third, measurement of lung function using spirometer. Fourth, examination of jute's dust at work place used low volume dust sampler. Result and Conclusion: This study find out the concentration of total jute's dust in high exposure working place is 13,3mg/m3, while in low exposure working place is 1,5 mg/m3. Result of statistic soon significant different (p<0,05). The study also finds out that the prevalence rate of chronic respiratory obstruction among the workers who work in high concentration dust environment is 25,9% and with low exposure is 2,8%. Statistically it is significantly different (p<0,05). There are a significant relationship between occurrence of chronic respiratory obstruction disease and dust concentration, while there are no relationship with age group, length of work, education level, height of body, smoking habit, use of personal protection device, previous clinical symptom and allergy history. The prevalence rate of acute respiratory obstruction among the workers who work in high concentration dust environment is 11,1%, while in low concentration dust environment is 3,7%. Statistically has not significantly different (p0,05). There are no relationship between acute respiratory obstruction disease and work place, age group, length of work, educational level, height of body, smoking habit, use of personal protection device, previous clinical symptom and allergic history. Analysis of smoking habit as risk factor and its relationship with obstruction can't be done since the prevalence rate of smoking habit among the workers is low (1,5%). "

"Tingginya penggunaan material polimer dengan matriks komposit (PMC) dalam berbagai aplikasi akhir ? akhir ini menimbulkan permasalahan baru terkait dengan ketebatasan sumber daya dalam memenuhi kebutuhan yang terus berkembang dan pengaruhnya terhadap lingkungan. Salah satu jalan keluarnya adalah mencoba mencari material PMC alternatif yang lebih ramah lingkungan serta memiliki kekuatan yang baik yaitu material komposit dengan matriks polimer berpenguat serat alam.Salah satu matriks untuk material PMC yang sering digunakan dan mudah dalam proses fabrikasinya adalah resin poliester tidak jenuh, matriks ini kemudian ditambahkan serat rami yang merupakan salah satu serat alam dengan kapasitas produksi dunia mencapai 100,000 ton pertahun.Pada penelitian ini ingin diketahui pengaruh fraksi volum serat rami terhadap kekuatan impak, kekuatan tekuk dan kekuatan tekan material komposit. Fraksi volum rami yang digunakan antara 15% - 35% dengan interval 5%. Proses fabrikasi dilakukan dengan menggunakan metode hand lay up, yang dikombinasikan dengan penambahan tekanan selama proses curing. Hal ini dikarenakan metode hand lay up merupakan metode paling sederhana dalam proses pembuatan komposit walaupun memiliki beberapa catatan tekait kualitas material komposit yang dihasilkan berupa ketidak-merataan matriks dan ketidaklurusan serat.Penambahan konsentrasi serat rami terhadap material komposit rami ?poliester secara umum memberikan pengaruh berupa peningkatan ketahanan impak dan kekuatan tekuk. Sedangkan untuk kekuatan tekan walaupun dari grafik hasil pengujian terlihat adanya peningkatan, namun kekuatan tekan material komposit rami ? poliester masih sangat rendah jika dibandingkan dengan material lain bahkan dibawah kekuatan material poliester murni. Hal ini dikarenakan rendahnya kualitas material komposit hasil fabrikasi dengan metode hand lay up.Nilai optimum konsentrasi serat pada penelitian ini terdapat pada konsentrasi serat rami 35 % Vf. Yaitu dengan kekuatan impak rata ? rata sebesar 82.38 KJ/m2, kekuatan tekuk rata ? rata sebesar 125 MPa dan kekuatan tekan rata?rata sebesar 80.22 MPa.

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The highly use of polymer matrix composite (PMC) in various application this days has caused another issues like environment and limited natural resources. One of the way out is to find alternative PMC materials which have good properties and also environment friendly like natural fiber reinforced composite (NFRC)Polyester is one of PMC matrix which has widely use in composite with various fiber and jute as fiber is natural fiber which production scale in the whole country extend one hundred million tons in one year.The purpose of this research is to know effect of jute fiber concentration on mechanical properties of jute polyester composite such as impact resistance, flexural strength and compressive strength. For fabrication, hand lay up process combining compressive load during curing time is used. This is because the hand lay up is the most simply method in accordance to making PMC. Although this method has some notes related to quality product such as fiber misalignment and matrix distributed.The addition of jute concentration in jute ? polyester composite has increased the value of impact resistance and flexural strength. While for compressive test decreased because of fabrication product by hand lay up method has low quality surface performance, compressive strength of jute polyester composite is very low compare to another materials even pure unsaturated polyester resin has higher compressive strength than jute ? polyester composite.The optimum volume fraction in this research is held by 35 % Vf of jute fiber concentration with impact resistance 82.38 KJ/m2, Flexural strength rate 125 MPa and compressive strength of material 80.22 MPa."

"Serat jute merupakan salah satu serat alam yang ramah lingkungan dengan harga relatif murah dan volume produksi relatif tinggi. Polipropilena dipilih sebagai matriks karena sifat unggul yang dimiliki dan dapat didaur ulang. Penelitian ini bertujuan mengetahui pengaruh fraksi berat serat jute sebagai penguat pada matriks polipropilena untuk mendapatkan nilai optimum fraksi berat serat jute pada komposit. Serat jute mendapat perlakuan awal dengan alkalisasi. Fabrikasi komposit polipropilena diperkuat serat jute diawali dengan metoda ekstruksi untuk polipropilena dan kemudian menyusun matriks polipropilena dan serat jute menjadi lamina menggunakan metode hot-press. Hasil uji tarik dan uji Heat Deflection Temperature memperlihatkan bahwa penambahan 40 wt% serat jute pada komposit polipropilena menaikkan kuat tarik sebesar 6% menjadi (38,2±4,9)MPa, modulus Young sebesar 50,2% menjadi (3,20±0,26)GPa dan suhu defleksi sebesar 143% menjadi (143,3±1,14)°C dibandingkan dengan PP murni. Hasil pengamatan dengan Scanning Electron Microscopy pada permukaan patahan diketahui bahwa mode kegagalan pada komposit adalah fiber pull-out. Dalam penelitian ini ditemukan bahwa komposit polipropilena diperkuat serat jute memiliki sifat mekanik yang tidak terlalu baik karena ikatan antarmuka serat-matriks yang tidak terlalu kuat "moda kegagalan fiber pull-out" menunjukan bahwa proses transfer beban dari matriks ke serat tidak terjadi dengan baik.

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Jute is one of eco-friendly natural fiber with relatively low cost and high volume production. Polypropylene was selected as a matrix due to good specific properties and recyclable. This study aimed to determine the effect of weight fractions of jute fiber as an reinforcement in the polypropylene matrix to obtain an optimum weight fraction of jute fiber on composites. Jute fiber was pre-treated through alkalization. The polypropylene based reinforced jute fiber composite was initially produced by extrusion process for the polypropylene, followed by fabricated the composites by compiling a polypropylene matrix and jute fiber into lamina using a hot-press methods.

The results of tensile test and heat deflection Temperature test showed that the addition of 40 wt% jute fiber to polypropylene composites increased the tensile strength about 6% up to (38.2±4.9)MPa, the Young modulus about 50.2% up to (3.20±0.26)Gpa, and the deflection temperature about 143% up to (143.3±1.14)°C compared to pure PP. Based on the observation on the fracture surfaces by Scanning Electron Microscopy, it was shown that the mode of failure on the composites failure surfaces are "fiber pull-out". It was found that the tensile properties of the jute fiber reinforced polypropylene composites were not very good due to the weak interface bond between the fiber and the matrix, the "fiber pull-out" failure, indicated that the load from matrix to fiber was not well transfered."