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"Polyhydroxyalkanoate(PHA) is one of the alternatively biodegradable plastics which can besynthesized from a particular micro-organism after the fermentation process,considering the optimization of nutrients. In this research, the yeaststrain Rhodotorula graminis TISTR 5124 was selected to be fermented with a carbonsource in the standard nutrient in order to conduct a preliminarily study on thebest conditions for thisyeast in PHA production. The growth rate curve of yeast in the composition of imbalancednutrients, i.e. the limitationof phosphorus and nitrogen, was also investigated and compared with another sample cultured in standard nutrients. Experimental results indicated that thecondition that gave the maximum growth rate of this yeast strain was aP-limited condition at 81 hours, whereby the cell number of 3.1×109cells/mL wasobtained and corresponded to the optical density (OD) of 0.95 measured at awavelength of 600 nm. The synthesized PHA extracted from yeast cells after 81hours of incubation was examined by Fouriertransform infra-red (FT-IR) and nuclear magnetic resonance (1H NMR) spectroscopy. The results indicated stretchingvibrations similar to the copolymer PHBV (or a PHA derivative). Maximum PHA content of 54.4% wasfound in the P-limited condition which correspondedto a PHA yield of 65.1 (g/g-total sugar consumed) in which the yeast consumed the least glucose amount of 3.2 g/L, butgrew the most rapidly. Rhodotorulagraminis TISTR 5124 is therefore promising as a good candidate for alternativelybiodegradable plastics, considering the potential to produce PHA and its derivatives. This process can be beneficial as an option to replace conventional plastics inthe future."

"Polyhydroxyalkanoate (PHA) is one of the alternatively biodegradable plastics which can be synthesized from a particular micro-organism after the fermentation process, considering the optimization of nutrients. In this research, the yeast strain Rhodotorula graminis TISTR 5124 was selected to be fermented with a carbon source in the standard nutrient in order to conduct a preliminarily study on the best conditions for this yeast in PHA production. The growth rate curve of yeast in the composition of imbalanced nutrients, i.e. the limitation of phosphorus and nitrogen, was also investigated and compared with another sample cultured in standard nutrients. Experimental results indicated that the condition that gave the maximum growth rate of this yeast strain was a P-limited condition at 81 hours, whereby the cell number of 3.1×109cells/mL was obtained and corresponded to the optical density (OD) of 0.95 measured at a wavelength of 600 nm. The synthesized PHA extracted from yeast cells after 81 hours of incubation was examined by Fourier transform infra-red (FT-IR) and nuclear magnetic resonance (1H NMR) spectroscopy. The results indicated stretching vibrations similar to the copolymer PHBV (or a PHA derivative). Maximum PHA content of 54.4% was found in the P-limited condition which corresponded to a PHA yield of 65.1 (g/g-total sugar consumed) in which the yeast consumed the least glucose amount of 3.2 g/L, but grew the most rapidly. Rhodotorula graminis TISTR 5124 is therefore promising as a good candidate for alternatively biodegradable plastics, considering the potential to produce PHA and its derivatives. This process can be beneficial as an option to replace conventional plastics in the future."

"Barium strontium titanate (BST) or Ba1-xSrxTiO3 with x=0-1 possesses superior dielectric properties, which are widely used in many applications like in communication technology, electronic instrumentations, and various electrical devices. In this paper, the characterization of the particle and crystallite size of Ba1-xSrxTiO3 (x: 0; 0.3; 0.7) is described. A two-step refinement commenced: first by mechanical milling, and then a further refinement under ultrasonic irradiation in a high power sonicator was applied to Ba1-xSrxTiO3 (x: 0; 0.3; 0.7) particles. The crystalline powders were obtained through mechanically alloyed standard research grade BaCO3, TiO2, and SrCO3 precursors in a planetary ball mill.The powders were first found heavily deformed after 60 hours of milling and then went through a sintering process at 1200°C for 4 hours to form multicrystallite particles. The presence of a single phase in the three samples was solidly confirmed in their respective X-ray diffraction (XRD) patterns. The changes of multicrystallite particles into monocrystallite particles were obtained only after crystalline powders were irradiated ultrasonically in a high power sonicator. The processing variable during ultrasonic irradiation was limited to the duration time of irradiation and particle concentration in the exposed media. It is shown that the average sizes of BST particles at x=0; 0.3; 0.7 before ultrasonic irradiation were 353, 348, and 385 nm, respectively. These respective sizes decreased drastically to 52, 35, and 49 nm, respectively, after 12 hours of ultrasonic irradiation. These particle sizes are almost identical with that of their crystallite size. Hence, the synthesis of monocrystallite particles has been achieved. As the particle concentration of media takes effect, it is shown that an exposed media with a higher particle concentration tends to form multicrystallite particles."

"Sintesis nanozeolit telah dilakukan dengan teknik seeding, dimana seed merupakan zeolit Y dengan tetraetilortosilikat (TEOS) sebagai sumber silika dan aluminium isopropoksida Al[((CH3)2CHO)]3 sebagai sumber aluminium dan tetrametilammonium hidroksida (TMAOH) sebagai molekul pengarah struktur. Proses kristalisasi dilakukan dengan teknik refluks pada suhu 100oC selama 192 jam. Kondisi optimum untuk pertumbuhan kristal zeolit adalah pada pH 9 dengan lama pertumbuhan kristal FAU selama 18 jam pada suhu 100oC dengan volume seed 10 mL dalam 20 mL larutan koloid FAU. Nanozeolit hasil sintesis dikarakterisasi menggunakan XRD, SEM-EDS, FTIR dan BET. Pola XRD menunjukkan nanozeolit memiliki struktur zeolit Y, yang diperkuat dengan rasio Si/Al sebesar 1,84 dari karakterisasi dengan EDS. Pencitraan dengan SEM menunjukkan bahwa kristal zeolit tumbuh saling bertumpuk membentuk agregat dengan ukuran 2 µm. Analisis dengan metode BET menunjukkan luas permukaan spesifik zeolit, diameter pori rata-rata dan volume pori berturut-turut adalah 521,682 m2/g, 10,667 Å, dan 0,2783 cc/g. Untuk pemisahan gas, telah dilakukan sintesis membran nanozeolit pada suatu kasa baja stainless dengan teknik redispersi. Membran selanjutnya diuji untuk aplikasi pemisahan gas metanol-etanol sebagai gas model dan dideteksi menggunakan GC-FID. Pengamatan awal menunjukkan bahwa gas etanol dapat tertahan oleh membran.

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AbstractNanozeolit synthesis was conducted by seeding method, in which the seed is a zeolite Y with tetraethyil orthosilicate (TEOS) as silica source and aluminium isopropoxide Al[((CH3)2CHO)]3 as a source of aluminum and tetramethylammonium hydroxide (TMAOH) as the structure directing agent. Crystallization process carried out by using reflux at a temperature of 100oC for 192 hours. The optimum conditions for crystal growth of zeolite crystals at pH 9 with FAU-term growth for 18 hours at a temperature of 100oC with seed volume 10 mL in 20 mL of colloid solution FAU. Nanozeolite synthesis products were characterized using XRD, SEM-EDS, FTIR and BET. XRD pattern shows nanozeolite has the structure of zeolite Y, which is reinforced with Si/Al ratio of 1.84 from the characterization by EDS. SEM imaging showed that the zeolite crystals grow over one another to form aggregates with a size of 2 µm. The analysis by the BET method shows specific surface area of zeolite, average pore diameter and pore volume are 521.682 m2/g, 10.667 Å and 0.2783 cc/g, respectively. For gas separation, synthesis membrane of nanozeolite has been done in a stainless steel mesh by redispersion method. Membranes were then tested for gas separation applications of methanol-ethanol as a gas model and detected using GC-FID. Initial observations indicate that ethanol gas can be restrained by the membrane. "

"Optimasi kontrol kuantum merupakan teknik untuk mengontrol suatu sistem kuantum melalui pulsa medan eksternal. Teori tersebut digunakan untuk mencapai tujuan tertentu pada pengukuran kuantum hingga menghasilkan presisi yang maksimum. Penelitian ini berfokus pada optimasi kontrol pada sistem kuantum hibrida antara sirkuit Qubit Superkonduktor Transmon dengan Nitrogen Vacancy Centers Ensemble. Sirkuit tersebut dihubungkan dengan Transmission Line Resonator yang dibantu oleh driving field. Metode optimasi pulsa yang diterapkan pada sistem ini menggunakan algoritma Chopped RAndom Basis. Hasil penelitian menunjukkan bahwa optimasi kontrol yang diterapkan pada driving field dapat meningkatkan nilai fidelitas transfer state dari 92% sampai 100% untuk menghasilkan gerbang kuantum c-phase dalam waktu 1.1 ns.

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Quantum control optimization is a technique for controlling a quantum system through external field pulses. The theory is used to achieve certain goals in quantum measurements to produce maximum precision. This research focuses on control optimization on a hybrid quantum system between the Transmon Superconducting Qubit circuit and the Nitrogen Vacancy Centers Ensemble. The circuit is connected to a Transmission Line Resonator assisted by a driving field. The pulse optimization method applied to this system uses the Chopped Random Basis algorithm. The results show that the control optimization applied to the driving field can increase the transfer state fidelity value from 92% until 100% to produce a c-phase quantum gate in 1.1 ns."

"Timbulan sampah di Kota Jakarta Selatan mencapai 1,937.54 ton per hari di tahun 2021. Rata-rata timbulan sampah terus merangkak naik hingga 17 ton setiap tahunnya. Permasalahan ini diakibatkan oleh pengelolaan sampah yang kurang baik, salah satunya pengelolaan di tempat penampungan sampah (TPS). Kelurahan Pejaten Barat memiliki TPS yang berlokasi di belakang Kantor Kelurahan Pejaten Barat yang dinamakan TPS Siaga. TPS Siaga menampung sampah dari seluruh RW di Kelurahan Pejaten Barat dan lokasi lainnya. Dalam situs SIPSN, sampah yang masuk pada TPS Siaga di tahun 2022 mencapai 19,130.36 ton per tahun. Sedangkan sampah yang terkelola hanya sebesar 222.7 ton per tahun, perbedaan antara sampah yang masuk dengan yang dikelola sangat signifikan. TPS Siaga juga bersinggungan dengan kali, ketika hujan lebat dan/atau kali meluap terjadi bencana banjir. Penelitian dilakukan untuk mengkaji pengelolaan dan pengolahan sampah di TPS Siaga, mengukur berat dan volume timbulan sampah yang masuk, mengidentifikasi komposisi limbah dan persentase jenis sampah sesuai, dan menganalisis potensi reduksi sampah yang mampu dicapai oleh TPS Siaga. Metode penelitian yang digunakan pada penelitian ini adalah observasi dan wawancara untuk mengetahui pengelolaan sampah yang dilakukan pada TPS Siaga, pengukuran timbulan sampah menggunakan metode load-count analysis, dan identifikasi komposisi menggunakan SNI 19-3964-1994. Hasil penelitian menunjukkan timbulan sampah yang masuk ke TPS Siaga dari wilayah pelayanan Kelurahan Pejaten Barat sebesar 3,477.368 kg per hari dengan volume sebesar 31.174 m3 serta timbulan sampah sebesar 0.081 kg/orang/hari atau 0.729 L/orang/hari. Komposisi sampah didominasi oleh sisa makanan sebesar 46.61%. Persentase komposisi sampah lainnya ialah kayu/ranting/daun sebesar 1.16%, kertas/karton 10.78%, plastik 18.17%, logam 1.05%, kain/tekstil 6.38%, karet/kulit 0.23%, kaca 1.69%, B3 0.71% dan sampah lainnya 13.21%. Pengelolaan sampah dari Kelurahan Pejaten Barat di TPS Siaga belum dilakukan dengan maksimal, karena nilai reduksi sampah hanya sebesar 27.77%. Hal ini menyebabkan timbulan sampah yang diangkut ke TPST Bantar Gebang mencapai 72.32% atau 2,511.768 kg per hari. Apabila sampah anorganik dipilah secara maksimal, dan sampah organik direduksi menggunakan maggot BSF dan pengomposan, maka nilai potensi reduksi sampah dapat mencapai 84.37% atau 2,933.805 kg per hari. Jumlah timbulan sampah yang tereduksi ke TPST Bantar Gebang mencapai 56.6% atau 1,968.205 kg per hari.

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Waste generation in South Jakarta City is up to 1,937.54 tons per day in 2021. The average waste generation continues to climb up to 17 tons every year. This problem is caused by poor waste management, such as what happened in the garbage collection site (TPS). Kelurahan Pejaten Barat has a TPS located behind Kelurahan Pejaten Barat Office called TPS Siaga. TPS Siaga accommodates waste from all RWs in Kelurahan Pejaten Barat and other locations. According to the SIPSN website, the waste entering TPS Siaga in 2022 is up to 19,130.36 tons per year. While the managed waste is only 222.7 tons per year, the difference between incoming and managed waste is very significant. TPS Siaga also intersects with rivers, when it rains heavily and/or overflows, floods occur. This research was conducted to study the management and processing of waste at TPS Siaga, measure the weight and volume of incoming waste generation, identify the composition of waste and the percentage of appropriate types of waste, and analyze the waste reduction potential that TPS Siaga can achieve. The research methods used in this study were observation and interviews to find out the waste management carried out at TPS Siaga, measurement of waste generation using the load-count analysis method, and composition identification using SNI 19-3964-1994. The results showed that waste generation that entered TPS Siaga from Kelurahan Pejaten Barat service area was 3,477,368 kg per day with a volume of 31,174 m3 and waste generation was 0,081 kg/person/day or 0,729 L/person/day. While the composition of the waste is dominated by food waste by 46.61%. The percentage composition of other waste is wood/branches/leaves of 1.16%, paper/cardboard 10.78%, plastic 18.17%, metal 1.05%, cloth/textile 6.38%, rubber/leather 0.23%, glass 1.69%, B3 0.71% and other waste 13.21%. Waste management from Kelurahan Pejaten Barat at TPS Siaga has not been carried out optimally, because the waste reduction value is only 27.77%. This causes the generation of waste transported to TPST Bantar Gebang up to 72.32% or 2,511.768 kg per day. If inorganic waste is optimally processed and organic waste is reduced using BSF maggot and composting, the potential value of waste reduction can be up to 84.37% or 2,933.805 kg per day. The amount of waste generated that is reduced to TPST Bantar Gebang is up to 56.6% or 1,968,205 kg per day."