Hasil Pencarian  ::  Simpan CSV :: Kembali

"

Pada penelitian ini, dilakukan investigasi karakteristik pelarutan plastic komoditas dalam biodiesel kelapa sawit dan pengaruhnya terhadap sifat biodiesel sebagai bahan bakar. Penelitian dilakukan melalui tiga tahap; (1) uji pendahuluan untuk memilah tipe plastik yang sesuai; (2) eksperimen utama untuk mengamati sifat pelarutan terhadap beberapa parameter, yakni: rasio plastic-biodiesel (0.5 – 2% w/w), temperatur pencampuran (25 – 150 °C), dan kecepatan agitasi (0 – 600 rpm), serta (3) evaluasi sifat laju alir dingin campuran bahan bakar plastik-biodiesel. Pelarutan yang seketika dapat terjadi untuk polistirena (PS), polietilena (PE) and polipropilena (PP) pada suhu 120 °C, 150 °C and 165 °C. Campuran polistirena-biodiesel cenderung untuk membentuk kembali endapan plastik pada suhu ruangan, sehingga pemakaian stabilizing agent (aseton) juga diuji untuk mempertahankan stabilitas campuran. Sifat laju alir dingin bahan yang terbaik adalah dengan penambahan 2% w/w polietilena yang mampu menurunkan titik awan dan titik tuang biodiesel menjadi 7 °C dan 0 °C. Ini adalah perbaikan yang cukup signifikan dari titik awan dan titik tuang biodiesel murni (13 °C dan 6 °C). Secara garis besar, aplikasi semacam ini dapat menjadi solusi gabungan untuk mengatasi kelemahan pada sifat bahan bakar biodiesel sekaligus sebagai upaya penanggulangan sampah plastik yang berlimpah - seturut dengan peribahasa ‘cencang dua segeragai’.

---

This research project investigated the dissolution characteristics of commodity plastics in palm biodiesel to enhance the fuel properties. The study was conducted in three stages; (1) preliminary testing to screen the suitable types of plastic; and (2) main experiment to assess the dissolution behaviour against few selected parameters, namely: plastic-to-biodiesel ratio (0.5 – 2% w/w), mixing temperature (25 – 150 °C), and agitation speed (0 – 600 rpm), and (3) assessment of plastic-biodiesel cold flow properties. Rapid dissolutions were achievable for polystyrene (PS), polyethylene (PE) and polypropylene (PP) at 120 °C, 150 °C and 165 °C, respectively. Unadulterated polystyrene-biodiesel tended to re-polymerize and precipitate in ambient temperature, which leads to the necessity of a stabilizing agent (acetone) to preserve blend stability. The best stable fuel blend was shown with the incorporation of 2% w/w polyethylene; capable of reducing the cloud and pour point to as low as 7 °C and 0 °C, respectively. It is a noteworthy improvement from 13 °C and 6 °C for neat palm biodiesel. In a wider picture, such application can help overcome the waste plastic pandemic and at the same time enhance palm biodiesel properties – resonating to the expression ‘to kill two birds with one stone’.

"

"Penelitian mengenai identifikasi keanekaragaman serta perhitungan kelimpahan mikroalga epiplastik di substrat sampah plastik makanan kemasan jenis polypropylene yang berpotensi menyebabkan Harmful Algal Blooms di lakukan di Pantai Lagoon Ancol dengan metode purposive random sampling pada 3 titik stasiun dengan metode subsample di bawah mikroskop. Tujuh belas genus mikroalga epiplastik ditemukan yang berasal dari tiga kelas, yaitu Bacillariophyceae (14 genus), Dinophyceae (1 genus), dan Cyanophyceae (2 genus) dengan 3 genus yang berpotensi toksik. Tujuh belas genus tersebut adalah Achnanthes, Cocconeis, Coscinusdiscus, Cymbela, Gyrosigma, Lyngbya, Mastogloia, Merismopedia, Navicula, Nitzschia, Paralia, Pleurosigma, Prorocentrum, Skeletonema, Stephanopyxis, Thalassionema, dan Thalassiosira. Hasil penelitian menunjukan kelimpahan total mikroalga epiplastik berkisar 249 – 24.051 sel/gram dengan kelimpahan terbesar dari genus Navicula sebesar 121.342 sel/gram dan terkecil dari genus Merismopedia sebesar 249 sel/gram. Berdasarkan perhitungan korelasi Pearson, hampir semua parameter lingkungan yang diukur berpengaruh sangat tinggi dengan rentang koefisien ± 0.80 – ± 1.00, dengan koefisien korelasi terendah oleh intensitas cahaya yaitu 0.3 dimana termasuk kedalam rentang berpengaruh rendah.

---

Research on identifying diversity and calculating the abundance of epiplastic microalgae in polypropylene plastic food packaging waste substrates that have the potential to cause Harmful Algal Blooms was conducted at Ancol Lagoon Beach with purposive random sampling method at 3 station points and using the subsample method under a microscope. Seventeen genera of epiplastic microalgae were found from three classes, namely Bacillariophyceae (14 genera), Dinophyceae (1 genus), and Cyanophyceae (2 genera) with 3 potentially toxic genus. The seventeen genera are Achnanthes, Cocconeis, Coscinusdiscus, Cymbela, Gyrosigma, Lygbya, Mastogloia, Merismopedia, Navicula, Nitzschia, Paralia, Pleurosigma, Prorocentrum, Skeletonema, Stephanopyxis, Thalassionema, and Thalassiosira. The results showed that the total abundance of epiplastic microalgae ranged from 249 – 24.051 cells/gram with the greatest abundance from the genus Navicula of 121.342 cells/gram and the smallest from the genus Merismopedia of 249 cells/gram. Based on Pearson correlation calculations, almost all environmental parameters measured have a very high effect with a coefficient range of ± 0.80 – ± 1.00, with the lowest correlation coefficient by light intensity of 0.3 which is included in the low influential range."

"Setiap tahun, ada sekitar 7.8 juta ton sampah plastik yang tidak dikelola di Indonesia. Metode yang banyak digunakan dalam pengolahan sampah tersebut adalah reduce, recycling, dan reusing. Dari ketiga metode tersebut, recycling menjadi solusi terbaik dalam penanganan sampah plastik karena kapasitas pengelolaan yang besar. Botol plastik menjadi jenis plastik yang paling banyak di recycling karena tingkat kemurnian material plastiknya tinggi. Namun, masalah terbesar dalam recycling sampah botol plastik adalah klasifikasi sampah plastik berdasarkan material penyusunya. Proses recycling saat ini sudah dimudahkan karena memanfaatkan machine learning. Machine learning dapat melakukan suatu pekerjaan tanpa harus diberi perintah berulang sehingga dapat dimanfaatkan untuk melakukan klasifikasi sampah botol plastik. Salah satu metode dalam Machine learning yang digunakan adalah Convolutional Neural Network karena dapat mengklasifikasikan sampah botol plastik PET, HDPE, LDPE, dan PP. Diperoleh akurasi testing PET terbaca sepuluh kali dari sepuluh percobaan sedangkan HDEP, LDPE, dan PP terbaca sembilan kali dari sepuluh percobaan. Selain itu, metode tersebut juga mampu mengklasifikasi sampah botol plastik dengan beberapa kondisi yaitu botol yang menggunakan tutup, kotor, serta remuk. Diperoleh akurasi testing untuk ketiga kondisi terbaca sepuluh kali dari sepuluh percobaan.

---

There are around 7.8 million tons of unmanaged plastic waste in Indonesia each year. Solving the problem there are three method that are widely used in processing the waste namely reduce, recycle, and reuse. From those methods, Recycling is the best solution in handling plastic waste because of its large management capacity. Plastic bottles are the type of plastic that is most widely recycled because of the high level of purity of the plastic material. However, the biggest problem in recycling plastic bottle waste is the classification of plastic waste based on its materials. The recycling process is now much easier because it utilizes machine learning. Machine learning can do a job without having to be given repeated orders so that it can be used to classify plastic bottle waste. One of the machine learning methods used is convolutional neural network because it can classify PET, HDPE, LDPE, and PP plastic bottles. PET testing accuracy was read ten times from ten times testing while HDPE, LDPE, and PP read nine times from ten times testing. In addition, this method is also able to classify plastic bottle waste under several conditions, namely using a lid, dirty, and crumbling. Obtained testing accuracy for all three condition read ten times from ten time testing."

"Kerjasama penelitian UI-Wika Beton dalam pengujian pada struktur spun pile yang tersambung ke pile cap dan dibebani secara siklik sampai mencapai keruntuhan guna mempelajari perilaku sambungan. Meskipun telah mencapai keruntuhan dan secara fisik struktur sudah masuk ke tahap damage atau non repairable, namun studi lanjutan dilakukan untuk mempelajari perilaku dari ketiga benda uji dengan memberikan perbaikan cepat berupa SikaPlate/SikaRod dan FRP Wrap. Studi lanjutan dengan pemodelan OpenSees dilakukan untuk mensimulasikan benda uji repair tersebut untuk menkaji lebih dalam stress dan strain development yang terjadi pada penampang spun pile.  Pemodelan dilakukan dalam 2 dimensi menggunakan software OpenSees. Non-linier fiber element digunakan untuk mensimulasikan penampang spun pile yang mengalami repair. Ditemukan bahwa OpenSees mampu memodelkan benda uji eksperimen dengan sangat baik pada fase linear sampai kondisi maksimum, namun kurang mampu menggambarkan fase damage pasca maksimum. Dari beberapa sensitivity analysis yang dilakukan, pemodelan yang paling mendekati benda uji yang mengalami rusak dan di-repair dengan memodelkan cross section tanpa memodelkan tulangan PC wire yang putus, menggunakan material steel01, memodelkan sambungan dengan bond slip, reduksi mutu beton sejauh  50% sebagai representasi berkurangnya kepadatan beton, serta reduksi tulangan infill  20% sebagai representasi regangan sisa. Hasil analisa menunjukkan bahwa repair terhadap sambungan spun pile mengakibatkan terjadinya tambahan plastic hinge yang semula berada pada daerah sambungan dengan pile cap ke bagian atas dengan tambahan plastic hinge baru di daerah berbatasan perkuatan. Hal yang menarik lainnnya yang ditemukan dari studi pemodelan OpenSees ini adalah nilai curvature yang terjadi pada spunpile dengan tulangan dan beton pengisi mampu mencapai curvature demand yang dibutuhkan pile untuk bertahan terhadap beban gempa.

---

A collaboration of research between UI-Wika Beton did a spun pile structure testing, where a spun pile that was attached to a pile cap was given cyclical load until it reached failure, in order to understand the behavior of connections. Although had reached failure, and physically entered the damage or non-repairable stage, further studies were conducted to study the behavior from 3 test specimens by giving rapid repair in the form of SikaPlate/SikaRod and FRP Wrap. A further study with OpenSees modeling is conducted to simulate the repair test specimen to have a deeper insight regarding the stress and strain development on spun pile cross sections. The modeling is done in 2 dimensions using OpenSees software. Non-linear fiber element was used to simulate spun pile cross section enduring the repair. It was discovered that OpenSees were able to excellently model experimental test specimens on a linear phase up until maximum condition, but are not able to illustrate the post-maximum damage phase. From several sensitivity analysis done, the closest modeling is obtained by modeling the cross section without modeling the snapped PC reinforcement, using steel01 material, modeling connections with bond slip, concrete quality reduction to 50% as void representation, and infill reinforcement reduction by 20% as residual strain representation. The analysis shows that a repair to a spun pile connection causes an increase of plastic hinge that was before located on a connection area from pile cap to the upper area, but now is included with the additional new plastic hinges in the area adjacent to the reinforcement. Another interesting thing discovered in the OpenSees modeling is that the curvature value for the spun pile is within the curvature demand range needed to survive seismic load."

"Tulisan ini ingin melihat bagaimana proses cheapening terjadi di dalam kapitalosen melalui infrastruktur, struktur, dan superstruktur pada sampah dengan kemasan plastik. Rumusan masalah ingin melihat bagaimana proses cheapening terjadi pada masyarakat Komplek Bumi Sawangan Indah Blok H, menjalani kesehariannya dengan plastik, dan mengapa barang FMCG sekali pakai masih digunakan. Metode yang digunakan adalah observasi partisipan dan wawancara. Kesimpulannya dalah bahwa kerusakan alam bukanlah bersifat anthropogenic, melainkan capitalogenic.

---

This writing wants to see how the cheapening process occurs in the capitalocene through the infrastructure, structure, and superstructure of goods with plastic packaging. The formulation of the problem wants to see how the cheapening process occurs in the people of the Bumi Sawangan Indah Complex Blok H, living their daily lives with plastic, and why single-use FMCG goods are still used. The methods used are participant observation and interviews. The conclusion is that natural damage is not anthropogenic, but capitalogenic."

"Pesatnya perkembangan industri membuat jumlah limbah plastik meningkat. Sulitnya limbah plastik untuk terdegradasi membuat penanganannya menjadi penting guna menghindari pencemaran lingkungan. Penelitian ini mengubah limbah plastik menjadi produk karbon bernilai ekonomi dalam upaya meningkatkan penerapan metode daur ulang sekaligus mendorong penggunaan energi terbarukan dengan menjadikan karbon tersebut sebagai bahan anoda baterai membentuk komposit LTO/C. Li4Ti5O12 memiliki keunggulan sebagai baterai litium ion seperti tingkat keamanan dan stabilitas termal yang baik namun konduktivitasnya buruk. Karbon hasil daur ulang tersebut diaktifasi menggunakan NaOH untuk mendapatkan struktur berpori yang dapat meningkatkan konduktifitas komposit tersebut. Penelitian ini ditujukan untuk mempelajari pengaruh penambahan karbon aktif hasil daur ulang terhadap kinerja baterai keseluruhan. Penelitian ini mensintesis LTO/C menggunakan metode ball mill dengan variasi waktu 90 menit, 120 menit, dan 150 menit guna mengetahui waktu sintesis komposit yang optimum untuk baterai. Uji EIS menunjukan penambahan karbon aktif hasil daurulang mampu meningkatkan konduktivitas LTO. Berdasarkan hasil uji EIS, CV dan CD waktu ball mill optimal adalah 90 menit untuk menghasilkan baterai dengan kinerja terbaik dan memiliki hambatan terendah dan kapasitas spesifik sebesar 149,8 Ω.

---

The rapid development of the industry makes the amount of plastic waste increase. The difficulty of plastic waste to be degraded makes its handling important to avoid environmental pollution. This research converts plastic waste into carbon products with economic value in an effort to increase the application of recycling methods while encouraging the use of renewable energy by making the carbon as an anode material for batteries to form LTO/C composites. Li4Ti5O12 has advantages as a lithium ion battery such as a good level of safety and thermal stability but poor conductivity. The recycled carbon is activated using NaOH to obtain a porous structure that can increase the conductivity of the composite. This study aimed to study the effect of adding recycled activated carbon to the overall battery performance. This study synthesized LTO/C using the ball mill method with variations in time of 90 minutes, 120 minutes, and 150 minutes in order to determine the optimum composite synthesis time for the battery. The EIS test showed that the addition of recycled activated carbon was able to increase the LTO conductivity. Based on the results of EIS, CV and CD the optimal ball mill time is 90 minutes to produce a battery with the best performance and has the lowest resistance and a specific capacity of 149.8 Ω."

"Litium Titanat atau Li4Ti5O12 (LTO) merupakan salah satu material yang menguntungkan sebagai bahan dasar anoda baterai lithium ion. Dalam penelitian ini, LTO disintesis dengan karbon aktif (AC) yang berbahan dasar dari sampah pelastik (PET), dengan komposisi karbon aktif yang berbeda sebesar 3 wt%, 5 wt%, and 7 wt%. Karbon aktif tersebut terbuat dari campuran sampah pelastik dan bentonite (9:1) yang dikarbonisasi melalui tungku pembakaran pada suhu 400°C dalam atmosfer inert nitrogen menjadi karbon amorf hitam. Setelah karbonisasi, karbon tersebut diaktivasi melalui empat proses utama: pencampuran dengan NaOH, sintering dalam atmosfir nitrogen, pencucian, dan pengeringan. LTO/AC yang sudah disintesis lalu diubah menjadi anoda baterai lithium-ion setengah sel. Kemudian anoda tersebut dikarakterisasi melalui Uji Voltametri Siklus, Uji Pengisian Daya Muatan (CD) dan Spektroskopi Impedansi Listrik (EIS). Hasil akhir dari pengujian ini menunjukan bahwa penambahan karbon aktif dapat meningkatkan konduktifitas dari baterai lithium-setengah sel. Sesuai dengan hasil pengujian CV, penambahan karbon sebesar 7% wt% menghasilkan kapasitas spesifik sebesar 143.4 (mAh/g). Hasil pengujian pada penelitian ini menunjukan bahwa penambahan karbon aktif optimal adalah sebesar 7 wt%.

---

Lithium titanate or Li4Ti5O12 (LTO) is a favorable contender as lithium-ion battery anode material. In this research, LTO/AC was synthesized with activated carbon made of plastic waste, the different composition of 3 wt%, 5 wt%, and 7 wt% has been carried out. The activated carbon was made using the mixture of plastic waste and bentonite nano clay (9:1) that will go through the slow pyrolysis carbonization process, which is performed under 400°C in an inert atmosphere of N2 with the help of a furnace into black amorphous carbon. After the carbonization, the carbon is activated through four main stages: mixing with NaOH, sintering under a nitrogen atmosphere, washing, and drying. The synthesized LTO/AC materials are then formed into a half-cell lithium-ion battery anode. The half cell lithium-ion battery anodes are then examined using the Cycle Voltammetry Test, Charge Discharge (CD) Test, and Electrical Impedance Spectroscopy (EIS). The final result of this research shows that activated carbon can increase the conductivity of the half-cell lithium battery. According to the results of the CV test, the addition of 7% wt% carbon resulted in a specific capacity of 143.4 (mAh/g). The test results in this research indicate that the optimal addition of activated carbon is 7 wt%."

"Bio-oil hasil produksi dari co-pyrolysis CPO-PP tidak dapat langsung digunakan sebagai bahan bakar untuk mesin karena masih mengandung oksigenat yang cukup banyak, korosif, dan tidak stabil. Pada penelitian ini, katalis ZrO2/α-Al2O3-TiO2 diharapkan dapat memperbaiki karakteristik bio-oil dan menciptakan bahan bakar yang memiliki karakteristik mendekati bahan bakar komersial. Katalis disintesis dengan suhu variasi suhu kalsinasi 1150oC dan laju pemanasan 7oC/menit. Pada proses catalytic co-pyrolysis dilakukan variasi komposisi polipropilena pada umpan yang digunakan (0%PP, 50%PP, dan 90%PP) dengan memasukkan katalis sebanyak 15% dari total umpan. Penelitian ini dilakukan menggunakan reaktor tangki berpengaduk dengan jumlah umpan 200 gram, kecepatan pemanasan 10oC/menit, suhu pirolisis 550oC, kecepatan pengadukan 80 rpm, dan laju alir gas nitrogen 100 ml/menit. Produk bio-oil terbaik dihasilkan pada variasi 50%PP dengan yield bio-oil sebesar 50%. Penggunaan katalis ZrO2/α-Al2O3-TiO2 dapat meningkatkan produksi alkana dan alkena dengan menurunkan kandungan asam karboksilat dan keton di dalam biofuel. Hal ini menunjukkan bahwa penggunaan katalis mampu memaksimalkan reaksi deoksigenasi, Berdasarkan analisis GC-MS, H-NMR, dan C-NMR senyawa yang paling dominan adalah alkana dan alkena.

---

Bio-oil produced from co-pyrolysis CPO-PP cannot be used directly as fuel for engines because it still contains a lot of oxygenate, is corrosive, and unstable. In this study, the ZrO2 / α-Al2O3-TiO2 catalyst is expected to improve the characteristics of bio-oil and create a fuel that has characteristics close to commercial fuels. The catalyst was synthesized with calcination temperature variations of 1150oC and heating rates of 7oC/minute. In the catalytic co-pyrolysis process, variations in the composition of polypropylene in the feed is used (0% PP, 50% PP, and 90% PP) and were carried out by adding a catalyst as much as 15% of the total feed. This research was conducted using a stirred tank reactor with a feed amount of 200 grams, heating rate 10oC/minute, pyrolysis temperature 550oC, stirring speed 80 rpm, and nitrogen gas flow rate of 100 ml/minute. The best bio-oil products are produced in variations of 50% PP with a bio-oil yield of 50%. The use of ZrO2/α-Al2O3-TiO2 catalysts can increase the production of alkanes and alkenes by reducing the carboxylic acid and ketone content in biofuels. This shows that the use of a catalyst is able to maximize the deoxygenation reaction. Based on the GC-MS, H-NMR, and C-NMR analysis the most dominant compounds are alkanes and alkenes."

"Written by leading teledermatologists and telemedicine experts, this hands-on guide addresses the practical needs of the many emerging teledermatology services worldwide. It covers the medical and technical prerequisites for such services as well as the photographic imaging essentials. It also illustrates the performance of teledermatology by means of clinical examples, discusses teledermatology in underdeveloped countries, and presents specialized methods of teledermatology. The impact of telemedicine on the doctor-patient relationship is explored, and the advantages that accrue from improving access to expert knowledge are explained. In addition, quality assurance, legal assumptions, economic aspects, and the future horizons of such health care services are all considered. A comprehensive appendix provides information on training opportunities, sample protocols, consent forms, information sheets, references, and relevant web links."

"This book focuses on strengthening and joining materials by means of plastic deformation, gathering extended research papers presented at the AIMTDR 2016 conference. Plastic deformation is used in materials processing to improve the strength of the material. For example, the rod/screw used to connect the cooker handle to the main body has to be strong and sustainable; such rods can be strengthened by plastic deformation (using multi-stage forming operations etc.). Similarly, joining by means of plastic deformation is highly valuable since it avoids the material and environmental degradation often caused by fusion welding processes. The book discusses various processing techniques in which plastic deformation is used to strengthen materials – e.g. in equal channel angular extrusion, autofrettage etc., or to join materials without melting them – e.g. in friction stir processing, riveting etc. Offering an extensive guide, the book includes chapters on roll bonding, equal channel angular pressing, autofrettage, friction stir processing/welding, magnetic pulse welding, and riveting – processes used to strengthen and join a variety of materials for lightweight applications and sustainable manufacturing. The contents of this book will be useful to researchers and practitioners alike. "