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"Azo dyes are the largest class of dyes used in industry, mainly in textile and paper making sectors. These compounds are difficult to be degraded biologically and in anaerobic environments could transforms into aromatic amine, which may be toxic and carcinogenic. This article discusses preliminary identification of degradation products of Orange II, an azo dye, by a fungus isolate Penicilium sp. L2 in aerobic conditions. The decolorization of Orange II in a laboratory scale batch process with an initial concentration of 0.1 g/l was completed after 74 hours of incubation. The degradation products was observed as three distinct spots on thin layer chromatography plates in solvent system of 1-propanol-water (25:75). Using the same mobile phase, the result of highperformance liquid chromatography analysis demonstrated that the number of intermediate products was increasing at a longer incubation time, up to a certain point, where some of these compounds were further decomposed. After 74 hours to 144 hours of incubation. Orange II has been transformed into at least five intermediate-products, separated at retention times of 4.14, 4.73, 6.03, 8.14, and 14.88 minutes, having maximum wavelengths of 207, 254, 227, 203, and 227 nm, respectively."

"Kondisi kerja dari cetakan plastik menuntut ketahanan terhadap berbagai faktor eksternal yang kompleks. Kegagalan yang sering dihadapi adalah keausan permukaan, deformasi struktural, bahkan fraktur pada bagian tertentu. Cacat material yang umum terjadi pada proses pembuatan cetakan plastik adalah orange peel, yang merupakan cacat yang menghasilkan pola permukaan yang terlihat seperti kulit jeruk dengan lembah-lembah dan bukit-bukit yang acak menutupi sebagian besar permukaan. Metode penelitian yang dilakukan meliputi machining, preparasi sampel, perlakuan panas, karakterisasi sampel, dan pemolesan. Karakterisasi sampel meliputi uji komposisi, uji kekerasan, metallografi, dan uji kekasaran sebelum dan setelah perlakuan panas. Proses perlakuan panas merupakan suatu proses yang digunakan untuk mengubah sifat fisik dan mekanik dari suatu material, biasanya logam dan paduannya, dengan cara memanaskannya secara terkontrol kemudian mendinginkannya. Berdasarkan hasil pengujian, diperoleh nilai akhir Ra sebesar 0.02µm untuk permukaan yang telah dipoles. Nilai ini menunjukkan bahwa kekasaran permukaan telah berhasil ditingkatkan secara signifikan, yaitu mencapai tingkat kehalusan yang sangat tinggi karena memenuhi kriteria untuk mencapai mirror finish. Material 420 ESR telah memenuhi standar untuk pembuatan cetakan speedometer karena kandungan karbon bernilai 0.382wt%. Proses perlakuan panas berhasil menghasilkan kekerasan mencapai 56.6 HRC dengan kekuatan tarik yang mencapai kisaran 2070-2105 N/mm2.......The working conditions of plastic molds demand resistance to various complex external factors. Failures often encountered are surface wear, structural deformation, and even fracture of certain parts. A common material defect in the plastic mold manufacturing process is orange peel, which is a defect that produces a surface pattern that looks like an orange peel with random valleys and hills covering most of the surface. The research methods include machining, sample preparation, heat treatment, sample characterization, and polishing. Sample characterization includes composition test, hardness test, metallography, and roughness test before and after heat treatment. The heat treatment process is a process used to change the physical and mechanical properties of a material, usually metals and their alloys, by heating it in a controlled manner and then cooling it. Based on the test results, the final Ra value of 0.02µm was obtained for the polished surface. This value indicates that the surface roughness has been significantly improved, reaching a very high level of smoothness as it meets the criteria for achieving a mirror finish. The 420 ESR material meets the standard for making speedometer molds because the carbon content is 0.382wt%. The heat treatment process successfully produced a hardness of 56.6 HRC with a tensile strength that reached the range of 2070-2105 N/mm2."

"ABSTRAKPada industri otomotif terdapat proses elektroplating sebagai bagian dariproses produksi. Proses ini menghasilkan limbah dengan kandungan logam nikelyang cukup tinggi kisaran 27,6 - 34,8 mg/L. Adsorpsi merupakan salah satualternatif pengolahan limbah secara fisik yang memiliki desain sederhana danmudah dalam pengaplikasiannya. Salah satu adsorben alami yang dapat dipakaiuntuk menyisihkan logam nikel adalah kulit buah jeruk lokal dari jenis jeruk siam(Citrus nobilis var microcarpa). Pada penelitian ini, percobaan adsorpsi dilakukansecara batch dengan metode two-level full factorial design untuk mendapatkanwaktu kontak dan dosis adsorben optimum. Dari hasil penelitian, kulit jerukberhasil dijadikan sebagai karbon aktif dengan nilai bilangan iodin sebesar 364,29mg/gr, nilai kadar air sebesar 2,9%, dan densitas sebesar 0,623 g/mL. Prosesadsorpsi secara batch dapat menyisihkan nikel sebanyak 18,3% dengan kombinasidosis adsorben optimum sebesar 36 g/L dan waktu kontak optimum 70 menit. Dataekuilibrium adsorpsi nikel menunjukkan kecocokan dengan model isothermFreundlich dengan nilai kapasitas adsorpsi sebesar qe = 0,23 mg/g. Data kinetikaadsorpsi menunjukkan kecocokan dengan pseudo-second order model dengan nilailaju kinetika knikel = 0,04 g/mg.menit.

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ABSTRACTIn the automotive industry there is an electroplating process as a part ofthe production process. This process produces a waste with nickel metal contentthat high enough with range of 27.6 to 34.8 mg/L. Adsorption is one of physicalwaste treatment alternative which has a simple design and easy to apply. One ofnatural adsorbent that can be used to reduce a nickel metal is local orange peel fromtangerine family (Citrus nobilis var microcarpa). In this study, an activated carbonsuccessfully made from orang peel with iodine number 364,29 mg/gr, water content2,9%, and density 0,623 g/mL. Batch adsorption experiments with two-level fullfactorial design method was conducted to get the optimum contact time andoptimum adsorbent dosage. From the result of this research, the batch adsorptioncan reduce 18,3% nickel with a combination of 36 g/L optimum adsorbent dose and70 minutes optimum contact time. Adsorption equilibrium data of nickel were bestfitted by Freundlich isotherm model with adsorption capacity values of qe = 0,23mg/g. Adsorption kinetics data were best fitted by the pseudo-second order kineticsmodel with a rate value knikel = 0,04 g/mg.minute."

"By reading this book, business people, academics and chain practitioners have an opportunity to understand this chain. and can analyse all of its numbers and economics and exercise strategy building. This is needed since the orange juice market is a stable market in the world, growing only 1% per year, and the production costs of this chain are rising fast, due to structural changes faced by world food and agribusiness companies i.e. labour costs, energy costs, land costs, environmental costs and others. "

"The study aimed to reveal the role of literary work, especially a novel in reflecting the social fenomena, the juvenile delinquency in the twentieth century. The data source was an English novel 'Clockwork Orange' written by Anthony Burgess. The research applied library research by using reflection theory introduced by George Lukacs. Analysis was pesented in three part, those were the identification of major character, social setting, and the reflection of juvenile delinquency. The findings were as follows, first, the major character was Alex as his high intensity in all the events that build the whole story. Second, the social setting described the life of teenagers, especially the juvenile delinquency as racial fenomena in society. Third, the role of literary work in revealing the problem above faced by the twentieth century society. Finally, it can be concluded that the literary work has played a very important role in revealing the social fenomena."

"Tesis ini membahas mengenai perbedaan citra ras kulit hitam, kulit putih dan Hispanik yang direpresentasikan dalam serial drama Orange is the New Black. Serial drama ini menampilkan tahanan-tahanan perempuan yang bergabung ke dalam sebuah kelompok berdasarkan identitas ras. Dalam tesis ini, kelompok yang direpresentasikan dalam serial drama tersebut dilihat sebagai kelompok pseudo-family, kelompok yang khas di dalam penjara perempuan, yang mereplikasi hubungan yang ada di dalam sebuah keluarga. Pseudo-family sering dijelaskan sebagai sesuatu memberikan manfaat bagi tahanan perempuan di dalam penjara karena hubungan yang saling mendukung dan melindungi. Namun dalam Orange is the New Black, pseudo-family juga diperlihatkan sebagai sesuatu yang bersifat manipulatif dan mempengaruhi anggotanya melakukan pelanggaran hukum. Hal tersebut terutama ketika tayangan ini menggambarkan pseudo-family dari kelompok tahanan kulit hitam. Namun, kelompok Hispanik digambarkan lebih positif dengan penggambaran pseudo-family yang bersifat memberdayakan anggotanya.

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This thesis examines the difference of black, white, and Hispanic images who were represented by drama series tittled Orange is the New Black. This drama series represents women prisones who join prison group based on their race identity. In this thesis, the groups who are represented by this drama series refered as pseudo family, typically prisoner group in women prison. Pseudo family is often explained as group that gives benefit for women prisones who are join in group because they support and protect each member. Yet, in Orange is the New Black, Pseudo family is depicted as group that manipulative and influence their members to break the law, especially when the drama depicted black pseudo family. In the other hand, Hispanic group is depicted to be more positive by showing Hispanic pseudo family that empower their member."

"Studi adsorpsi methyl orange (MO) menggunakan adsorben karbon aktif dan lumpur alum telah dilakukan untuk mengetahui efektivitas adsorben serta mengetahui faktor-faktor yang mempengaruhi eksperimen pada tingkat penyisihan MO. Beberapa faktor pengaruh yang diamati pada proses adsorpsi ini adalah efek konsentrasi adsorben, konsentrasi polutan, pH, temperatur, kecepatan pengadukan, volume reaksi serta penggunaan kembali adsorben (reuse). Studi dilakukan karena MO merupakan salah satu zat pewarna yang berbahaya dalam industri tekstil yang memiliki dampak terhadap manusia dan lingkungan. Berdasarkan eksperimen parametrik yang dilakukan pada adsorben karbon aktif diketahui bahwa seiring dengan naiknya konsentrasi adsorben, efisien penyisihan polutan MO juga meningkat sebesar 99,87% pada 1 g/L karbon aktif. Sedangkan pada efek konsentrasi polutan MO berbanding terbalik dimana semakin besar konsentrasi polutan yang diberikan, tingkat penyisihan pada adsorben semakin menurun, yaitu dari 95,89% menjadi 16,8%. Dan untuk adsorben lumpur alum, efisiensi penghilangan polutan MO sangat kecil hanya 5% dengan aktivasi KOH. Dari kedua perbandingan adsorben yang telah dilakukan, karbon aktif merupakan adsorben yang efektif digunakan untuk menghilangkan polutan methyl orange di air dengan persentase removal hampir 100% pada konsentrasi adsorben 0.5 g/L. Karbon aktif juga dapat diregenerasi dengan efisiensi penyisihan mencapai 80%."