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"Treatment of pulp bleaching effluent using Upflow Anaerobic Sludge Blanket (UASB) and Suspended Carrier Biofilm (SCB) systems have been carried out. Upflow Anaerobic Sludge Blanket (UASB) and Suspended Carrier Biofilm (SCB) reactors were run on the Hydraulic. Retention Time (HRT) of 12 hours, respectively. Micronutrient solution containing some traces elements was added into feed wastewater of UASB reactor to accelerate the growth of granular sludge. Sludge characteristics of UASB and activeted sludge reactors were observed and analyzed. Settling rate of granular reactor was also measured. Effluent of UASB reactor was treated further in Susoended Carrier Biofilm (SCB) reactor. Concentration of COD, TSS and AOX parameters both influent and effluent of UASB reactor as well as suspended carrier biofilm (SCB) reactor were analyzed. Result revealed that UASB reactor run on the Hydraulic Retention Time (HRT) of 12 hours could remove COD up to 90 % and AOX up to 84 %. Addition of micronutrient solution has accelerated the growth of granular sludge. Dark-brownesh color of granular sludge with the diameter of 1-4 mm having settling rate of 70-120 m/hr has been formed. SCB reactor as post-treatment could remover COD of 85%, TSS of 73 % and AOX of 76%. Sequential UASB and SCB reactor could increase the effectivity of pulp and paper mill wastewatertreatment with the removal of dissolved and suspended organic pollutant more than 94%."

"Tempat Pembuangan Akhir (TPA) Bantargebang merupakan tempat pembuangan terbesar di Indonesia yang menjadi pembuangan akhir kota Jakarta dan sekitarnya. Salah satu masalah yang sering timbul dari TPA adalah adanya limbah lindi yang dihasilkan. Lindi yang dihasilkan dari TPA mengandung polutan tinggi yang berpotensi merugikan kesehatan dan lingkungan sehingga pengolahan lindi dibutuhkan untuk mencegah dampak negatif terhadap lingkungan dan kesehatan masyarakat. Salah satu proses pengolahan lindi yang saat ini banyak dikembangkan adalah Advanced Oxidation Processes (AOPs) berbasis ozon dan plasma. Proses yang terjadi adalah dengan menginjeksikan gas ke dalam reaktor plasma dielectric barrier discharge (DBD) sehingga menghasilkan radikal hidroksil (OH•) dan ozon (O3) sebagai oksidator kuat yang akan mendegradasi limbah. Pengolahan limbah lindi yang dilakukan saat ini adalah menggunakan Reaktor Ozon Plasma Nanobubble (ROPN) yang mana telah terbukti dapat menghasilkan degradasi jauh lebih tinggi daripada reaktor ozon plasma saja. Untuk meningkatkan efektivitas degradasi, dilakukan penambahan karbon aktif granular (GAC) ke dalam sistem ROPN sebagai adsorben dan katalis. Penelitian dilakukan selama 60 menit dengan variasi tegangan, konfigurasi, dan jenis umpan gas. Hasil yang diperoleh pada kondisi optimum adalah terjadinya penurunan pH sebesar 5,59%; Chemical Oxygend Demand (COD) sebesar 87,49%; Total Suspended Solids (TSS) sebesar 100%; Total Dissolved Solids(TDS) sebesar 45,46%; Nitrat sebesar 91,12%; dan Biological Oxygen Demand (BOD) sebesar 93,67%.

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The Bantargebang Waste Disposal Site (TPA) is the largest landfill in Indonesia which is the final disposal site for the city of Jakarta and its surroundings. One of the problems that often arises from TPA is the leachate waste produced. Leachate produced from TPA contains high levels of pollutants that have the potential to be detrimental to health and the environment, so leachate processing is needed to prevent negative impacts on the environment and public health. One of the leachate processing methods that is currently being developed is Advanced Oxidation Processes (AOPs) based on ozone and plasma. The process occurs by injecting gas into the dielectric barrier discharge (DBD) plasma reactor to produce hydroxyl radicals (OH•) and ozone (O3) as strong oxidants that will degrade the waste. The current processing of leachate waste is using a Nanobubble Plasma Ozone Reactor (ROPN) which has been proven to produce much higher degradation than a plasma ozone reactor alone. To increase the effectiveness of degradation, granular activated carbon (GAC) was added to the ROPN system as an adsorbent and catalyst. The research was carried out for 60 minutes with variations in voltage, configuration and type of gas feed. The results obtained under optimum conditions were a decrease in pH of 5.59%; Chemical Oxygen Demand (COD) of 87.49%; Total Suspended Solids (TSS) of 100%; Total Dissolved Solids (TDS) of 45.46%; Nitrate of 91.12%; and Biological Oxygen Demand (BOD) of 93.67%."

"Cooling systems in tropical countries consume a large portion of the overall energy usage in a building, especially in tropical climates, where there is an especially high demand on cooling systems throughout the year. This paper presents a simulation of the effect of zeolite adsorbent granular size on a zeolite-water solar adsorption chiller for Universitas Indonesia. The adsorption chiller is being mathematically modeled and calculated numerically, using MATLAB®. The mathematical modeling is based on heat transfer principles inside the system for the water inlet and outlet of the system. The adsorption chiller is based on the most recent chiller developed by Shanghai Jiao Tong University (SJTU). The simulation results generally demonstrated the running characteristics of the chiller under a range of different values of granular size. The average granular sizes used in the simulation ranged from 0.5 mm to 1.5 mm. Furthermore, the simulation results showed in detail that the smaller the average granular size of zeolites, the faster the time needed to reach the maximum hot water temperature and the balance state of chilled water outlet temperature."

"This textbook explores the theory of Cosserat continuum mechanics, and covers fundamental tools, general laws and major models, as well as applications to the mechanics of granular media. While classical continuum mechanics is based on the axiom that the stress tensor is symmetric, theories such as that expressed in the seminal work of the brothers Eugène and François Cosserat are characterized by a non-symmetric stress tensor. The use of von Mises motor mechanics is introduced, for the compact mathematical description of the mechanics and statics of Cosserat continua, as the Cosserat continuum is a manifold of oriented “rigid particles” with 3 dofs of displacement and 3 dofs of rotation, rather than a manifold of points with 3 dofs of displacement. Here, the analysis is restricted to infinitesimal particle displacements and rotations. This book is intended as a valuable supplement to standard Continuum Mechanics courses, and graduate students as well as researchers in mechanics and applied mathematics will benefit from its self-contained text, which is enriched by numerous examples and exercises. "

"Dalam masa pakainya, kerusakan refraktori di dalam tanur tidak dapat dihindari. Namun demikian, tidak berarti kerusakan akan terjadi dalam waktu yang singkat, seperti halnya dalam studi kasus ini. Pada umumnya perbaikan pada kerusakan refraktori dilakukan satu atau dua kali dalam satu tahun.Kondisi pemakaian yang dapat menyebabkan refraktori menjadi tidak efektif adalah pengaruh kimia, seperti : gas, kerak, dll. Cara pengoperasian pabrik; serta tegangan mekanis. Sampel refraktori yang dipakai dalam pengamatan ini berasal dari patahan bata magnesia dari bagian busur tanur dan refraktori alumina yang terdegradasi dari bagian pengapian. Kompilasi data, pengamatan mikro, sifat fisik, perlakuan termal serta kandungan unsure/senyawa dilakukan dengan tujuan untuk mengetahui penyebab kerusakan pada refraktori. Hasil analisa menunjukkan terjadinya dekomposisi reduksi MgO, tegangan termal dan kejut termal yang cukup besar pada bata magnesia sehingga sifat kerefraktorian bata berkurang. Sedangkan pada refraktori alumina terdapat penetrasi senyawa baru yang tidak teridentifikasi, refraktori mengalami swelling -40% ekspansi linier, yang menimbulkan kerusakan intergranutar dan transgranular. Pada keduanya diketahui adanya pengaruh atmosfir yang korosif.

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Damage in refractories used as kiln linings is common, Generally, repairs to fracture linings are about twice a year. On the contrary, the furnace component lifetimes in this case study have been shortened. Service conditions that might impair effectiveness of refractories include chemical attack by, eg. , slags, gases, etc, operational conditions, and mechanical stress. Sample for analysis were obtained from two sources ; (1) fracture magnesia refractory from arches of the furnace, and (2) degraded alumina refractory from the burner side of the furnace. Research was conducted to identify caused of the refractories fracture by data compilation, macroscopic and microscopic examinations, physical and chemical analysis, and behavior of samples on elevated temperature. Result indicated that reduction -- decomposition of MgO, thermal stress and thermal shock have been of concern as a potential mechanism of recession of magnesia refractories, while unidentified new compound penetrated alumina refractories. A combination of transgranular and intergranular fracture caused swelling to the alumina bricks -40% of lineair expansion. Both are also exposured to corrosive atmosphere."

"Tujuan penelitian ini adalah untuk mengetahui pengaruh prestrain terhadap perilaku korosi retak tegang stainless steel AISI 304 dalam larutan H2SO4 konsentrasi 10% dengan pembebanan kantilever statis (ASTM E-1681). Prestrain dilakukan dengan meregangkan spesimen hingga mencapai regangan merata 5% dan 10% diatas tegangan luluh bahan, menggunakan servopulser UTM 9506 dengan kontrol kecepatan 0,3 mm/sec.Hasil pengujian menunjukan bahwa spesimen dengan 5% prestrain lebih cepat mengalami kegagalan daripada spesimen 10% prestrain dan tanpa prestrain. Hal ini disebabkan menurunnya keuletan dan periode inkubasi yang singkat. Perubahan defleksi hanya dapat diamati pada pembebanan 20% tegangan luluh bahan. Retak intergranular ditemukan pada spesimen 10% prestrain pada pembebanan statis 616 MPa. Sedangkan pada specimen 10% prestrain ditemukan retak transgranular pada pembebanan statis 554,4 MPa. Retak kombinasi ditemukan pada specimen 5% prestrain pada pembebanan statis 369,6 MPa. Semakin tinggi densitas dislokasi pada lapisan permukaan akibat deformasi plastis, semakin sulit difusi hidrogen pada ujung retak. Konsekuensinya, periode inkubasi dapat diperlama.

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Stress Corrosion Cracking Behavior of Stainless Steel 304 in the Sulfuric Acid Environment Due to Prestrain. The aim of research is to investigate the effect of prestrain on the stress corossion cracking behavior of AISI 304 stainless steel in the sulfuric acid of 10% concentration under the static cantilever loading according to ASTM E-1681 standart. The specimen of 304 Stainless steel was strain up over the yield strength until reaching the uniform strain of 5% and 10% using servopulser UTM 9506 under the displacement control of 0,3 mm/sec.The results of test show that the prestrain of 5% specimen is faster failure than both of the prestrain of 10% and unprestrain specimen. It was caused by both of the decrease of ductility and the short incubation period. The change of deflection could be only recorded under the loading 20% of yield strength. Intergranular crack was the prestrain of 10% specimen under the static loading of 616 MPa. Whereas, for the prestrain of 10% specimen transgranular crack was found under the static loading of 554,4 MPa. The prestrain of 5% specimen was mixed crack under the static loading of 369.6 MPa. Higher dislocation density on the layer surface due to plastic deformation with increasing the percentage of pre-strain, so more difficult hydrogen diffused into the crack tip. Consequently, The incubation period can be prolonged."

"Indonesia has imported asphlt from other countries to meet the need for road construction and annual maintenance. Mearwhile in Buton Island, Southeast Sulawesi Province, there is natural asphalt known asbuton that as been produced since 1926"

"Tahanan gelincir pada jalan merupakan salah satu parameter yang sangat penting untuk keselamatan berkendara. Nilai tahanan gelincir ini menentukan kekesatan dari suatu jalan yang dimana jalan dapat menjadi lebih licin saat basah dan dapat membahayakan pengendara saat melakukan perjalanan. Penelitian ini menggunakan alat British Pendulum Tester (BPT) yang sudah dimodifikasi. Pengujian ini dilakukan untuk mengetahui pengaruh suhu terhadap tahanan gelincir aspal buton dengan campuran hangat yang berisar dari 100 ˚C-140 ˚C yang dimodifikasi dengan penambahan aspal minyak pen 60/70, oli bekas, dan Nano Crumb Rubber (NCR). Aspal buton yang digunakan merupakan Lawele Granular Asphalt (LGA) merupakan Rock Asphalt yang diperkirakan berbentuk linear belt yang membentang dari Teluk Sampolawa hingga Teluk Lawele (Darsana, 2005). Pengujian dilakukan pada permukaan yang basah dengan suhu yang digunakan pada penelitian ini adalah 26 ˚C, 30 ˚C, 35 ˚C, 40 ˚C, 45 ˚C, dan 50 ˚C. Pengujian ini dilakukan sebanyak dua kali untuk pengujian skid resistance standard dan pengujian skid resistance immersion. Sehingga kedua hasil tersebut dibandingkan. Nilai skid resistance menurun seiring dengan kenaikan suhu permukaan. Pada pengujian ini didapatkan nilai uji skid resistance immersion lebih besar daripada nilai uji skid resistance standard yang dimana nilai SN tertinggi adalah 54.9 pada suhu 26 ˚C untuk uji skid resistance immersion dan untuk uji skid resistance standard nilai SN tertinggi adalah 42.6 pada suhu 26 ˚C. Hal ini menandakan bahwa benda uji skid resistance immersion lebih kesat dibandingkan dengan nilai skid resistance standard.

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Skid resistance on the road is one of the critical parameters that are for driving safety. The value of skid resistance determines the surface roughness of a road, where the road can become more slippery when the road is wet and can endanger the driver when traveling. This research used the modified British Pendulum Tester (BPT) tool. This test was conducted to determine the influence of temperature against the Buton Asphalt with a warm mixture ranging 100 ° C-140 ° C and modified with the addition of pen 60/70 asphalt oil, used oil, and Nano Crumb Rubber (NCR). Buton asphalt used is the Lawele Granular Asphalt (LGA) is a Rock Asphalt which is thought to form a linear belt stretching from Sampolawa Bay to Lawele Bay (Darsana, 2005). Tests conducted on wet surfaces with the temperatures used in the study were 26 °C, 30 °C, 35 °C, 40 °C, 45 °C, and 50 °C. This test was done twice for testing standard skid resistance and immersion skid resistance testing. So the two results are compared. The value of skid resistance decreases as the surface temperature rises. In this test, the value of skid resistance immersion is greater than the standard skid resistance test value, where the highest SN value is 54.9 at 26 °C for immersion skid resistance test and for standard skid resistance test the highest SN value is 42.6 at 26 °C This indicates that the test object of immersion skid resistance is rougher than the standard skid resistance value"

"This text provides a comprehensive investigation of the role of disorder in the nonlinear optical propagation both in transparent media and lasers. Eventually, disorder promotes and enhances complex nonlinear dynamics opening new perspectives in applied research driven by the processes of localization of the electromagnetic field. The first experimental study of laser emission in granular media unveils how randomness magnifies and largely affect laser-matter interactions. "

"Penelitian tesis ini berbasis pada dekomposisi ozon keluaran reaktor pengolahan air minum kemasan, proses desinfeksi pada industri susu dan makanan yang dapat membahayakan kesehatan makhluk hidup dan merusak lingkungan. Dekomposisi ozon menggunakan katalis berinti aktif MnOx dengan loading nominal 0?2%. Sebagai komparasi digunakan penyangga katalis seperti Zeolit Alam Lampung, Karbon Aktif Granular dan Pasir Hijau dengan diameter 18?100 mesh. Katalis dipreparasi dengan cara incipient wetness impregnation dan kalsinasi pada temperatur 300°C. Kinerja katalis sebagai konversi dekomposisi ozon diuji dalam reaktor unggun tetap secara kontinu. Diketahui bahwa katalis berpenyangga Karbon Aktif Granular berdiameter 60?100 mesh dan konsentrasi loading nominal 1% lebih efektif dan efisien dibandingkan yang lain dengan konversi dekomposisi 100% selama 24 jam. Kualitas katalis dikarakterisasi dengan metode BET dan SEM EDX dengan hasil luas permukaan 558,754 m2/g dan loading aktual 0,47%.

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This thesis based on ozone decomposition from water bottled processing reactor, desinfection in dairy and food industry emissions which its dangerous for the living things and destruct the environment. Ozone decomposition use MnOx as active site with nominal loading 0?2%. Catalyst support as comparative study use Lampung Natural Zeolite, Granular Activated Carbon and Green Sand with 18 ? 100 mesh in diameter. Catalyst is prepared by incipient wetness impregnation and calcination at 300°C.

Catalyst performance as ozone decomposition conversion is tested in continue fixed bed reactor. It knew that Granular Activated Carbon as catalyst support with 60?100 mesh in diameter and 1% loading nominal has decomposition conversion 100% for 24 hours, is the most effective and efficient than others. The catalyst quality is characterized by BET methode and SEM EDX which the surface area is 558.754 m2/g and actual loading 0.47%."