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"The addition of alumina and wollastonite in geopolymer resin is expected to increase the thermal behavior of the geopolymer matrix composite. In this work, fine granules of solid alumina and acicular wollastonite used as filler were mixed with a fly ash-based geopolymer resin paste to form a composite matrix. The filler additions were 2.5% to 10.0% of the total weight with sodium silicates and sodium hydroxide used as activators. The results showed that the addition of alumina and wollastonite as filler did not have much effect on the flexural and compressive strength of the geopolymer matrix composite at room temperature. Wollastonite fiber, which was added in the form of a short-sized fiber, only produced a very small bridging effect. Nevertheless, alumina filler composite showed a good result after being exposed to a temperature at 200°C, although the strength was reduced as the temperature increased. Moreover, wollastonite fibers only managed to maintain 50% of their flexural strength after 2 hours exposure at a temperature of 200°C due to the damage of the wollastonite fiber."

"Mayoritas cangkang kapsul hingga tahun 2014 masih berbahan gelatin yang bersumber dari kulit dan tulang babi. Untuk mengatasi masalah tersebut, riset cangkang kapsul nabati mulai berkembang dengan berbahan dasar ekstrak rumput laut seperti karagenan, alginat, HPMC, dan pektin. Cangkang kapsul nabati yang sudah ada perlu diberi penambahan polihidroksibutirat (PHB), sebuah biopolimer yang tahan suhu tinggi, tahan pH ekstrem, biodegradable, biocompatible, hingga cocok untuk slow release. Metode isolasi dari S. platensis yang paling simpel dan ekonomis dengan tahapan umum berupa disrupsi sel, presipitasi PHB, dan pemurnian PHB. Sodium hipoklorit adalah pelarut pendisrupsi sel yang banyak digunakan untuk isolasi PHB dari mikroalga sedangkan sodium hidroksida bisa digunakan untuk isolasi PHB dari E. coli. Parameter yang diuji dalam penelitian ini adalah konsentrasi sel sampel S. platensis serta rasio konsentrasi pelarut NaClO dan NaOH yang ditambahkan. Metode identifikasi PHB adalah FTIR, kuantifikasi PHB dengan menghitung massa dan yield PHB secara manual, lalu mengestimasi perbandingan nilai ekonomi proses isolasi pada tiap variabel. Pada kondisi pelarut NaClO 0,0265 M, hasil dengan yield terbaik ditunjukkan pada variasi 0,04 g/mL dengan massa PHB 2 x 10-3 g dan yield 0,16 %. Hasil dengan keuntungan tertinggi adalah variasi konsentrasi sampel 0,06 g/mL dengan yield 0,12%. Penggunaan NaOH sebagai tambahan rasio pelarut meningkatkan pH larutan dengan terlalu drastis sehingga mengurangi efektivitas isolasi PHB oleh NaClO.

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The majority of capsule shells until 2014 are still made from gelatin sourced from pork skin and bones. To overcome this problem, research on vegetable capsule shells began to develop based on seaweed extracts such as carrageenan, alginate, HPMC, and pectin. Existing vegetable capsule shells need to be added with polyhydroxybutyrate (PHB), a biopolymer that is high temperature resistant, extreme pH resistant, biodegradable, biocompatible, and suitable for slow release. The simplest and most economical method of isolation from S. platensis with general stages is cell disruption, PHB precipitation, and PHB purification. Sodium hypochlorite is a cell disrupting solvent that is widely used for extraction of PHB from microalgae while sodium hydroxide can be used for extraction of PHB from E. coli. The parameters tested in this study were the concentration of S. platensis sample cells and the ratio of NaClO and NaOH solvent concentrations added. The PHB identification method is FTIR, PHB quantification by calculating mass and PHB yield manually, then estimating the comparison of the economic value of the extraction process for each variable. In the conditions of NaClO 0.0265 M, the best yield results were shown in the variation of 0.04 g/mL with a mass of PHB 2 x 10-3 g and a yield of 0.16%. The results with the highest gain are variations in sample concentration of 0.06 g/mL with yields of 0.12%. The use of NaOH in addition to the solvent ratio increases the pH of the solution too drastically thereby reducing the effectiveness of PHB isolation by NaClO."

"Unsur transisi merupakan unsur yang terdapat pada golongan 3-12. Unsur transisi ini memiliki bilangan oksidasi yang bervariasi. Dengan adanya hal tersebut menyebabkan unsur transisi memiliki kemampuan sebagai katalis yang baik dan memiliki kemampuan penyerapan zat pada permukaan yang baik. Selain unsur transisi juga terdapat Logam Tanah Jarang LTJ . Unsur LTJ terdapat pada deret lanthanida dan juga Yttrium Y dan Scandium Sc .Terak timah merupakan limbah slag dari proses peleburan timah. Terak timah yang digunakan yaitu terak timah I. Terak timah dapat dimanfaatkan untuk mendapatkan mineral berharga seperti Tantalum Pentaoksida Ta2O5 dan Niobium Pentaoksida Nb2O5 dan LTJ. Proses diawali dengan pemanggangan, pencelupan pada larutan NaOH 0.5M. Kadar Ta2O5 dan Nb2O5 mengalami penurunan setelah proses pemanggangan. Setelah itu dilakukann proses pelindian menggunakan larutan pelindi HCl dengan konsentrasi 4M, 6M dan 8M. Kadar dari mineral pengikut mengalami penurunan tetapi kadar dari Ta2O5, Nb2O5, Ce2O3 serta La2O3 juga mengalami penurunan.

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Transition elements or transition metal is an element contained in group 3 to 12 on the table periodic. The transition elements have two or more oxidation numbers. Given this causes the transition elements have the ability as a good catalyst, and has the ability absorption on the surface of the well. On the otherhand there is also a Rare Earth Elements REE . Rare Earth Elements are in series lanthanida and Yttrium Y and Scandium Sc . Tin slag is a waste from the lead smelting process. Tin slag has a valuable mineral that can be used as Tantalum Pentoxide Ta2O5 , Niobium Pentoxide Nb2O5 and Rare Earth Element REE . In this research, leaching is a process used to increase grade of Ta2O, Nb2O5 and REE Cerium Ce and Lanthanum La in tin slag. This research to found effect of roasting on 900 C, effect of using sodium hydroxide NaOH as a quenching agent and effect of variation chloride acid HCl concentration as leaching agent. The roasting result was obtained highest mass distribution on 100 and use to leaching process. But grade of Ta2O5, Nb2O5 and REE after roasting process was decreased. The result of leaching in variation concentration 4M, 6M, and 8M grade of gangue minerals was decreased but Ta2O5, Nb2O5 and REE also decreased."

"Tantalum dan Niobium masuk kedalam logam critical in mid term yang diperkirakan akan habis pada tahun 2020. Berdasarkan ketersediaan sumber, terak timah dapat menjadi sumber alternatif untuk mendapatkan logam tantalum dan niobium dalam bentuk Tantalum Pentaoksida Ta2O5 dan Niobium Nb2O5 . Di terak timah juga mengandung Logam Tanah Jarang LTJ oksida yang dapat ditingkatkan kadarnya. Penelitian ini bertujuan untuk mengetahui peningkatan kadar Tantalum, Niobium dan LTJ dengan menggunakan proses pelindian dengan variabel bebas temperatur pelindian Terak timah dilakukan pemanggangan di temperatur 900 C selama 2 jam lalu didinginkan dengan cepat menggunakan larutan NaOH 0.5 M, kemudian dilakukan pengayakan dengan ukuran 100, minus;100 120, minus;120 180. Setelah itu dilakukan pelinidan dengan menggunakan larutan HCl 6 M, S/L 1:30, dan lama pelindian ialah 50 menit. Pelindian dilakukan dengan variabel bebas yaitu temperatur pelindian. Temperatur pelindian yang digunakan ialah 25 , 45 , 65 C. Hasil penelitian ini menunjukan setelah pemanggangan dan pendinginan cepat distribusi ukuran terbanyak di ukuran 100 dan terjadi penurunan kadar Tantalum, Niobium, dan LTJ. Hasil pelindian menunjukan semakin tinggi temperatur maka kadar Tantalum, Niobium, dan LTJ di terak timah meningkat, didapatkan temperatur optimun pelindian di 45 C dengan peningkatan sebesar 240 untuk Niobium dan 164.3 untuk Tantalum.

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Tantalum and Niobium were known include as critical in mid term, expected to be exhausted in 2020. Based on availability sources, Tin Slag can be an alternative source for Tantalum Pentaoxide Ta2O5 , Niobium Pentaoxide Nb2O5 and Rare Earth Elements REE.

This research aimed to find out effect of effect Natrium Hydroxide as quenching media and leaching process with variable of temperatur leaching for increasing Tantalum, Nobium, and REE oxides grade with leaching process. Tin slang roasted at 900 C for two hours and quenched in NaOH 0.5 M, the sieved to the size of 100, minus 100 120, minus 120 180. Leaching process with Chloride Acid 6 M, S L 1 30, and leached for 50 minutes. The leaching variable temperature used were 25 , 45 , 65 C.

The roasting and quencheds result showed the highest mass distribution at 100 and the grade were decreased. The result of leaching, higher temperature leaching then Tantalum, Niobium, and REE oxides grade increased. The optimum temperature was 45 C, increased 240 for Niobium and 164.3 for Tantalum."

"Geopolimer concrete in the world of sustainable construction is not as popular as Portland concrete Because it doesn rsquo t have fixed mix design yet The goals of the this research are the mix design with strength of K225 K300 dan K350 by seeing the compressive strength dan flexural strength by 80 C curing The result age of this concrete is 7 days and it has been obtained high strength and flexural strength form the SNI.

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Beton geopolimer dalam dunia konstruksi ramah lingkungan belum sepopuler dari beton Portland Karena belum memiliki desain campuran yang pasti Tujuan dilakukan penelitian ini adalah untukmencari desain campuran dengan kekuatan K225 K300 dan K350 dengan melihat kuat tekan dan kuat lentur dengan dilakukan curing pada suhu 80 C Hasil yang didapat melalui penelitian ini dengan umur 7 hari mendapatkan hasil kuat tekan kuat lentur yang lebih baik dari SNI."

"The effect of steel slag substitution as coarse aggregate on compressive strength in fly ash based-geopolymer concrete was studied. The compressive strength was evaluated by measuring the maximum acceptable load using compression testing equipment. Compressive strength depends on several factors, such as time and temperature of curing and the mixing proportion. The compressive strength of geopolymer concrete with steel slag substitution was higher compared to geopolymer concrete with gravel aggregate. The optimum compressive strength was found on the third day of curing at a temperature of 60oC for both the geopolymer concrete with steel slag substitution and normal geopolymer concrete. Reinforcement corrosion was evaluated by measuring the corrosion current density using a linear polarization potentiostatic scan. The corrosion rate of reinforcing steel in geopolymer concrete with steel slag substitution was found to be higher compared to normal geopolymer concrete without steel slag in seawater medium, whereas in an acid rain environment, steel slag substitution increased corrosion resistance. The corrosion rate of geopolymer concrete with steel slag substitution was found to be lower compared to normal geopolymer concrete. The corrosion rate was found to be very high at an early stage and decreased with time."

"ABSTRAKReduksi selektif bijih nikel laterit tipe saprolitik dengan kandungan Ni, Fe, MgO, dan SiO2 masing-masing sebesar 1,71%, 18,93%, 13,4%, dan 24,64% telah dilakukan dengan variasi penambahan zat aditif sodium hidroksida dan sulfur. Reduktor yang digunakan terdiri dari dua jenis, yaitu lignite dan batubara sub-bituminous dengan temperatur reduksi divariasikan menjadi 900oC, 1000oC, dan 1100oC, masing-masing selama 60 menit. Kadar nikel meningkat dari 3,91% menjadi 4,2% dengan kenaikan temperatur dari 900oC hingga 1100oC, dan perolehan nikel juga mengalami peningkatan dari 83% pada suhu reduksi 900oC menjadi 91% pada suhu 1100oC. Penambahan sulfur menyebabkan kenaikan recovery nikel dari 60% pada penambahan 0% sulfur menjadi 87% dengan penambahan 9% sulfur. Reduksi tanpa penambahan NaOH hanya mampu mencapai recovery nikel maksimum sebesar 67%, sedangkan penambahan 16,4% NaOH mampu meningkatkanrecovery secara signifikan hingga 89%. Reduksi yang dilakukan dengan memanfaatkan reduktor lignite menghasilkan kecenderungan recovery Ni yang lebih tinggi dibandingkan dengan reduktor sub-bituminous. Reduksi dengan reduktor sub-bituminous menunjukkan hasil perolehan nikel maksimum 67%, sedangkan pemanfaatan reduktor lignite mampu menghasilkan nikel dengan perolehan hingga 89%.Fasa-fasa yang terbentuk pada reduksi selektif nikel laterit dengan penambahan NaOH, antara lain forsterite (Mg2SiO4), olivine [(Mg,Fe)2SiO4], taenite (FeNi), dan natrium silikat (Na2Si2O5). Sedangkan sulfur berperan penting dalam pembentukan fasa pyroxene [(Ca,Mg,Fe)2Si2O6] dan mencegah terjadinya pembentukan fasa olivine dan forsterite yang bersifat menyelubungi oksida nikel yang hendak direduksi. Selain itu sulfur juga berperan penting dalam prosesaglomerasi butiran metalik hingga 50μm dengan penambahan sulfur sebesar 9% dari ukuran butiran yang hanya mencapai 5μm dengan penambahan 0,5% sulfur.

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ABSTRACTSelective reduction of nickel laterit saprolitic ore with Ni, Fe, MgO, and SiO2 contents 1.71%, 18.93%, 13.4%, and 24.64% respectively, has been conducted with some variated sodium hydroxide and sulphur amounts. Reduction has been done by usingtwo types of reductors, such as lignite and sub-bituminous coal at various reduction temperatures (900oC, 1000oC, and 1100oC) along 60 minutes of reduction timefor each temperatures. Nickel grades increased from 3.91% to 4.2% due to increasing reduction temperature from 900oC to 1100oC. Nickel recovery rose up regarding to increasing temperature from 83% at 900oC to 87% at 1100oC. Sulphur addition gave significant effects on resulted nickel recoveries, from 60% without any addition to 87% with addition of 9% sulphur. Selective reduction with no NaOH addition could only reach 67% of nickel recovery, while 89% nickel could be attained with 16.4% of NaOH. The usage of lignite as solid reductor indicated higher nickel recoveries compared to those with sub-bituminous coal. Selective reduction using sub-bituminous as reductor had maximum nickel grade at 67%. Meanwhile, 89% of nickel recovery could be achieved with employing lignite as solid reductor.Some phases formed after reduction of saprolitic nickel ore with sodium hydroxide addition, such as forsterite (Mg2SiO4), olivine (Mg,Fe)2SiO4, taenite (FeNi), dan natrium silikat (Na2Si2O5). Whereas, sulphur had important role in the formation of iron-rich silicate (pyroxene) phase and impediment of the crystallization of olivine and forsterite phases that inhibit nickel and iron oxides to be reduced. According to backscatter imagesby SEM, fact that sulphur can induce the metallic grain agglomeration is also found. The grain size with excessive sulphur addition (9%) is 50μm, while the addition of only 0.5% sulphur had maximum metallic grain size by 5μm"

"ABSTRAKNama : Andi CleveriawanProgram studi : Ilmu Kesehatan MataJudul : Perbandingan Hasil Trabekulektomi MMC Dengan Dan Tanpa Viskoelastik Sodium Hyaluronat Terhadap Morfologi Bleb Pada Glaukoma PrimerPembimbing : Widya Artini, Joedo Prihartono Penelitian ini bertujuan mengetahui manfaat pemberian viskoelastik sodium hyaluronat pada pasien glaukoma primer yang dilakukan bedah trebekulektomi dengan mitomicin C di RSCM. Desain penelitian ini adalah uji klinis prospektif tersamar tunggal. Sebanyak 34 mata 33 pasien yang masing- masing terbagi menjadi 2 kelompok, yaitu 17 mata diberikan viskoelastik dan 17 mata pada kelompok yang diberikan tanpa viskoelastik. Pemeriksaan Tekanan bola mata TIO diukur pada hari 1, minggu 1, minggu 2, dan minggu ke 4 pasca operasi. Penilaian bleb dengan menggunakan Moorfield Bleb Grading System MBGS dilakukan pada minggu ke 4.Setelah 1 bulan pasca operasi, pada pemeriksaan MBGS area sentral, area maksimal, ketinggian, dan vaskularitas pada kedua kelompok tidak ditemukan perbedaan bermakna. Namun pada pemeriksaan TIO minggu 1 didapatkan terdapat perbedaan bermakna pada kelompok viskoelastik sebesar 8,94 3,36 dan pada kelompok tanpa viskoelastik sebesar 11,41 3,72 p = 0,034 . Meskipun pada TIO pada minggu ke 4 tidak didapatkan perbedaan bermakna pada kelompok viskoelastik sebesar 11,70 2,46 dan tanpa viskoelastik sebesar 12,35 3,08 p = 0,504 . Perubahan TIO pada kelompok viskoelastik didapatkan sebesar 21,88 12,29 dan tanpa viskoelastik sebesar 23,29 9,25 p = 0,352 . Pada pemeriksaan OCT ketinggan bleb pada kedua kelompok juga tidak didapatkan perbedaan bermakna yaitu 1,28 0,325 dan 1,17 0,324 p = 0,321 .Tekanan intra okular dan morfologi bleb pasca tindakan trabekulektomi MMC dengan penambahan viskoelastik tidak berbeda bermakna statisik namun memiliki kecenderungan lebih baik dibandingkan tanpa vikoelastik. Kata kunci :Glaukoma primer, MBGS, sodium hyaluronat, trabekulektomi, viskoelastik

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ABSTRACTName Andi CleveriawanStudy Program OphthalmologyTitle Comparison Of Trabeculectomy MMC With And Without Sodium Hyaluronate Viscoelastic Results To Bleb Morphology In Primary GlaucomaCounsellor Widya Artini, Joedo Prihartono To determine the benefits of viscoelastic sodium hyaluronate in primary glaucoma patients performed by trebeculectomy surgery with mitomycin C in RSCM. Clinical prospective single blinded clinical trial. A total of 34 eyes 33 patients , each split into 2 groups, 17 eyes were given viscoelastic and 17 eyes in the group administered without viscoelastic. Examination of Eye Pressure IOP was measured on day 1, week 1, week 2, and week 4 postoperatively. Assessment of bleb using Moorfield Bleb Grading System MBGS was performed at week 4. After 1 month postoperatively, MBGS examination of central area, maximal area, height, and vascularity in both groups found no significant difference. However, at week 1 IOP examination, there were significant differences in the viscoelastic group of 8.94 3.36 and in the no viscoelastic group of 11.41 3.72 p 0,034 . Although in the IOP at week 4 there was no significant difference in the viscoelastic group of 11.70 2.46 and without viscoelastic at 12.35 3.08 p 0,504 . IIO changes in the viscoelastic group were found to be 21.88 12.29 and without viscoelastic at 23.29 9.25 p 0.352 . In the OCT examination, bleb height in both groups also did not get significant difference that is 1.28 0.325 and 1.17 0.324 p 0.321 . Intraocular pressure and bleb morphology post trabeculectomy MMC action with viscoelastic addition did not differ significantly statistically but had a better tendency than without vicoelastic. Keywords MBGS, primary glaucoma, sodium hyaluronate, trabeculectomy, viscoelastic"