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Ditemukan 2003 dokumen yang sesuai dengan query
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"INTISARI. Dilakukan eksperimen teknik laser optogalvanik untuk mendeteksi transisi atom neon dalam lampu lucutan dengan cara mengarahkan berkas laser ke dalam lampu lucutan dan diamati perubahan tegangan akibat adanya serapan oleh transisi elektron dalam aras-aras tenaga atom neon. Eksperimen ini dikerjakan dengan menggunakan laser zat-warna (rhodarnine 6G + rhodamine B) tertala, yang dipompa dengan laser pulsa."
JURFIN 1:2 (1997)
Artikel Jurnal  Universitas Indonesia Library
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"Telah diteliti spektroskopi eksitasi dua foton dengan metode optogalvanik pada atom neon menggunakan lampu lucutan katoda berongga Na/Ne komersial dan laser zat warna Rh-B pulsa tertala. Laser zatwarna ini mempunyai rentang panjang gelombang antara 570 nm-603 nm dan lebar garis sekitar 0,6 nm. Variasi arus lucutan pada lampu dan intensitas lasr pengeksitasi yang cukup tinggi mampu mengidentifikasi 6 transisi dua foton neon dalam lampu katoda"
JURFIN 9:27 (2005)
Artikel Jurnal  Universitas Indonesia Library
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Wirya Sarwana
"[ABSTRAK
Peningkatan kesadaran akan ancaman polusi lingkungan mendorong pengembangan pengolahan limbah yang lebih efisien dan berkesinambungan. Material semikonduktor TiO2 merupakan material yang diharapkan memegang peranan penting dalam penyelesaian permasalahan polusi lingkungan melalui pemanfaatan energi matahari berbasis perangkat fotovoltaik termodifikasi. Sistem hibrid Dye Sensitized Solar Cell (DSSC)-katalisis merupakan salah satu pendekatan penyelesaian permasalahan limbah dikarenakan dapat mengoksidasi berbagai senyawa limbah serta pengaktifan dalam jangkauan panjang gelombang sinar tampak menyebabkan sistem ini menjadi lebih efisien.
Pada penelitian ini, fabrikasi sistem hibrid DSSC-katalisis menggunakan TiO2 nanotube yang disintesis melalui teknik Rapid Breakdown Anodization pada beda potensial 15 V dalam elektrolit 0,15 M HClO4. Pengujian performa sistem hibrid DSSC-katalisis menggunakan simulasi limbah rhodamine B dalam air. Beberapa variasi yang dilakukan adalah zat warna yang digunakan, perbandingan luas daerah warna dan daerah katalisis, serta perbandingan komposisi campuran fase anatase-rutil dalam TiO2. Variasi ini dilakukan untuk mengetahui kondisi optimum device DSSC-katalisis dalam mendegradasi rhodamine B.
TiO2 hasil sintesis dikalsinasi pada suhu 400°C selama 3 jam dan 2 jam serta 500°C selama 3 jam, lalu dikarakterisasi menggunakan XRD, UV Vis DRS, FTIR, FESEM, dan EDX. Hasil karakterisasi UV-Vis DRS menunjukkan band gap TiO2 hasil sintesis berkisar antara 3-3,5 eV. Sementara hasil uji FTIR yang menunjukkan ada puncak spesifik disekitar daerah 400-700 cm-1. Pada FESEM EDX, terlihat hasil yang cukup baik dalam bentuk bundle nanotube yang membuktikan bahwa teknik RBA dapat digunakan dalam proses sintesis TiO2 nanotube.
TiO2 hasil sintesis digunakan untuk merangkai sistem hibrid DSSC-katalisis menggunakan rhodamine B dan ekstrak buah naga sebagai zat warnanya. Zona katalisis pada hibrid DSSC diuji aktivitas katalisisnya, dimana persen degradasi oleh sistem bersensitizer rhodamine B sebesar 65,22% dan ekstrak buah naga sebesar 34,78% dengan lama penyinaran masing-masing 60 menit. Hal ini menunjukkan bahwa dalam sistem ini, rhodamine B memberikan hasil yang lebih baik. Pengujian selanjutnya menggunakan sensitizer rhodamine B dengan variasi perbandingan luas zona warna dan zona katalisis sebesar 1:2, 1:1, dan 1:0,5 dan diperoleh persen degradasi berturut-turut 40,19%; 25,01% ; dan 9,59%. Dengan demikian perbandingan optimum pada variasi ini adalah luas zona warna dan katalis yang paling baik adalah 1:2. Pengujian ketiga menggunakan TiO2 dengan komposisi campuran fase kristal anatase rutil sebesar 100% anatase 0% rutil.

ABSTRACT
An increasing concern on environmental pollution lead to development for more efficient and sustainable waste treatment. Titanium dioxide is expected to play an important role to solve the environmental pollution problem by using solar energy based on modified photovoltaic devices. Hybrid Dye Sensitized Solar Cell (DSSC) -catalysis system may become an efficient approach to solve the problem not only causes of the oxidizing power to degrade almost organic non biodegradable compounds in the waste but also the activation energy of this system still in visible light range. In this study, fabrication of hybrid DSSC - catalysis system used TiO2 nanotubes which was synthesized by Rapid Breakdown Anodization method, the potential difference was 15 V in 0.15 M HClO4. Degradating ability testing for hybrid DSSC ?catalysis system using simulated waste rhodamine B dispersed in water. Several variations has been done as kind of the dye used for the system, the wide comparison of dyes zone and catalytic zone, and composition of mixed crystalline phase ratio of anatase and rutile in TiO2 used. The purpose of the variation was to determine the optimum conditions for DSSC - catalysis device in degrading rhodamine B. TiO2 synthesized was calcined up to 400 ° C for 3 hours and 2 hours and 500°C for 3 hours. It was characterized using XRD, UV- Vis DRS, FTIR, FESEM, and EDX. UV- Vis DRS showed the band gap of samples between 3-3.5 eV. The result of FTIR measurements showed there was peak around the region 400-700 cm-1. FESEM EDX results showed very good shape of TiO2 nanotube bundle which proves that the RBA technique can be used in the synthesis process. Testing for determine the better sensitizer between rhodamine B and dragon fruit extract has been done. Based on the results of UV Vis measurements, percent degradation of rhodamine B system up to 65.22% and dragon fruit extract only 34.78%. Each of them exposure by visible light for 60 minutes. It indicates that in this system, rhodamine B sensitizer gives the better results. Further testing using sensitizer rhodamine B with a wide comparison of dye zone and catalytic zones by 1: 2, 1: 1 and 1: 0.5 and obtained percent of degradation respectively 40.19%; 25.01%; and 9.59%. Thus the optimum ratio in this variation is 1: 2. The third testing using the composition of the mixture TiO2 anatase-rutile crystalline phase 100% anatase 0% rutile, 92.88% anatase 7.12% rutile and 17.08% anatase 82.92% rutile with a percent of degradation for each sample were 66.80%, 81.01%, and 70.37%. The test results showed that the best phase in the system is the mixture of anatase 92.88% rutile 7.12%. Based on the three variations known that the system would work better if using rhodamine B as a;An increasing concern on environmental pollution lead to development for more efficient and sustainable waste treatment. Titanium dioxide is expected to play an important role to solve the environmental pollution problem by using solar energy based on modified photovoltaic devices. Hybrid Dye Sensitized Solar Cell (DSSC) -catalysis system may become an efficient approach to solve the problem not only causes of the oxidizing power to degrade almost organic non biodegradable compounds in the waste but also the activation energy of this system still in visible light range. In this study, fabrication of hybrid DSSC - catalysis system used TiO2 nanotubes which was synthesized by Rapid Breakdown Anodization method, the potential difference was 15 V in 0.15 M HClO4. Degradating ability testing for hybrid DSSC ?catalysis system using simulated waste rhodamine B dispersed in water. Several variations has been done as kind of the dye used for the system, the wide comparison of dyes zone and catalytic zone, and composition of mixed crystalline phase ratio of anatase and rutile in TiO2 used. The purpose of the variation was to determine the optimum conditions for DSSC - catalysis device in degrading rhodamine B. TiO2 synthesized was calcined up to 400 ° C for 3 hours and 2 hours and 500°C for 3 hours. It was characterized using XRD, UV- Vis DRS, FTIR, FESEM, and EDX. UV- Vis DRS showed the band gap of samples between 3-3.5 eV. The result of FTIR measurements showed there was peak around the region 400-700 cm-1. FESEM EDX results showed very good shape of TiO2 nanotube bundle which proves that the RBA technique can be used in the synthesis process. Testing for determine the better sensitizer between rhodamine B and dragon fruit extract has been done. Based on the results of UV Vis measurements, percent degradation of rhodamine B system up to 65.22% and dragon fruit extract only 34.78%. Each of them exposure by visible light for 60 minutes. It indicates that in this system, rhodamine B sensitizer gives the better results. Further testing using sensitizer rhodamine B with a wide comparison of dye zone and catalytic zones by 1: 2, 1: 1 and 1: 0.5 and obtained percent of degradation respectively 40.19%; 25.01%; and 9.59%. Thus the optimum ratio in this variation is 1: 2. The third testing using the composition of the mixture TiO2 anatase-rutile crystalline phase 100% anatase 0% rutile, 92.88% anatase 7.12% rutile and 17.08% anatase 82.92% rutile with a percent of degradation for each sample were 66.80%, 81.01%, and 70.37%. The test results showed that the best phase in the system is the mixture of anatase 92.88% rutile 7.12%. Based on the three variations known that the system would work better if using rhodamine B as a;An increasing concern on environmental pollution lead to development for more efficient and sustainable waste treatment. Titanium dioxide is expected to play an important role to solve the environmental pollution problem by using solar energy based on modified photovoltaic devices. Hybrid Dye Sensitized Solar Cell (DSSC) -catalysis system may become an efficient approach to solve the problem not only causes of the oxidizing power to degrade almost organic non biodegradable compounds in the waste but also the activation energy of this system still in visible light range. In this study, fabrication of hybrid DSSC - catalysis system used TiO2 nanotubes which was synthesized by Rapid Breakdown Anodization method, the potential difference was 15 V in 0.15 M HClO4. Degradating ability testing for hybrid DSSC ?catalysis system using simulated waste rhodamine B dispersed in water. Several variations has been done as kind of the dye used for the system, the wide comparison of dyes zone and catalytic zone, and composition of mixed crystalline phase ratio of anatase and rutile in TiO2 used. The purpose of the variation was to determine the optimum conditions for DSSC - catalysis device in degrading rhodamine B. TiO2 synthesized was calcined up to 400 ° C for 3 hours and 2 hours and 500°C for 3 hours. It was characterized using XRD, UV- Vis DRS, FTIR, FESEM, and EDX. UV- Vis DRS showed the band gap of samples between 3-3.5 eV. The result of FTIR measurements showed there was peak around the region 400-700 cm-1. FESEM EDX results showed very good shape of TiO2 nanotube bundle which proves that the RBA technique can be used in the synthesis process. Testing for determine the better sensitizer between rhodamine B and dragon fruit extract has been done. Based on the results of UV Vis measurements, percent degradation of rhodamine B system up to 65.22% and dragon fruit extract only 34.78%. Each of them exposure by visible light for 60 minutes. It indicates that in this system, rhodamine B sensitizer gives the better results. Further testing using sensitizer rhodamine B with a wide comparison of dye zone and catalytic zones by 1: 2, 1: 1 and 1: 0.5 and obtained percent of degradation respectively 40.19%; 25.01%; and 9.59%. Thus the optimum ratio in this variation is 1: 2. The third testing using the composition of the mixture TiO2 anatase-rutile crystalline phase 100% anatase 0% rutile, 92.88% anatase 7.12% rutile and 17.08% anatase 82.92% rutile with a percent of degradation for each sample were 66.80%, 81.01%, and 70.37%. The test results showed that the best phase in the system is the mixture of anatase 92.88% rutile 7.12%. Based on the three variations known that the system would work better if using rhodamine B as a, An increasing concern on environmental pollution lead to development for more efficient and sustainable waste treatment. Titanium dioxide is expected to play an important role to solve the environmental pollution problem by using solar energy based on modified photovoltaic devices. Hybrid Dye Sensitized Solar Cell (DSSC) -catalysis system may become an efficient approach to solve the problem not only causes of the oxidizing power to degrade almost organic non biodegradable compounds in the waste but also the activation energy of this system still in visible light range. In this study, fabrication of hybrid DSSC - catalysis system used TiO2 nanotubes which was synthesized by Rapid Breakdown Anodization method, the potential difference was 15 V in 0.15 M HClO4. Degradating ability testing for hybrid DSSC –catalysis system using simulated waste rhodamine B dispersed in water. Several variations has been done as kind of the dye used for the system, the wide comparison of dyes zone and catalytic zone, and composition of mixed crystalline phase ratio of anatase and rutile in TiO2 used. The purpose of the variation was to determine the optimum conditions for DSSC - catalysis device in degrading rhodamine B. TiO2 synthesized was calcined up to 400 ° C for 3 hours and 2 hours and 500°C for 3 hours. It was characterized using XRD, UV- Vis DRS, FTIR, FESEM, and EDX. UV- Vis DRS showed the band gap of samples between 3-3.5 eV. The result of FTIR measurements showed there was peak around the region 400-700 cm-1. FESEM EDX results showed very good shape of TiO2 nanotube bundle which proves that the RBA technique can be used in the synthesis process. Testing for determine the better sensitizer between rhodamine B and dragon fruit extract has been done. Based on the results of UV Vis measurements, percent degradation of rhodamine B system up to 65.22% and dragon fruit extract only 34.78%. Each of them exposure by visible light for 60 minutes. It indicates that in this system, rhodamine B sensitizer gives the better results. Further testing using sensitizer rhodamine B with a wide comparison of dye zone and catalytic zones by 1: 2, 1: 1 and 1: 0.5 and obtained percent of degradation respectively 40.19%; 25.01%; and 9.59%. Thus the optimum ratio in this variation is 1: 2. The third testing using the composition of the mixture TiO2 anatase-rutile crystalline phase 100% anatase 0% rutile, 92.88% anatase 7.12% rutile and 17.08% anatase 82.92% rutile with a percent of degradation for each sample were 66.80%, 81.01%, and 70.37%. The test results showed that the best phase in the system is the mixture of anatase 92.88% rutile 7.12%. Based on the three variations known that the system would work better if using rhodamine B as a]"
2015
T43280
UI - Tesis Membership  Universitas Indonesia Library
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"Telah dilakukan eksperimen yang memperlihatkan bahwa lampu lucutan dapat berlaku sebagai cuplikan dan detektor sekaligus, sehingga dapat dipergunakan untuk tehnik spektroskopi optogalvanik dengan cara mengarahkan berkas laser zatwarna (RmG, Rh-B, atau DCM) ke katoda lampu lucutan. Perekaman spektrum optogalvanik dan spektrum laser zatwarna secara bersamaan dilakukan dengan cara memisahkan berkas laser menjadi dua berkas, satu berkas kearah lampu lucutan untuk memperoleh sinyal optogalvanik dan berkas yang lain kearah meter panjang gelombang untuk menentukan panjang gelombang laser zatwarna pada saat terjadi resonansi. Pada puncak resonansi (2. = 588,3 dan 614,4 nm) diperoleh sinyal temporal optogalvanik. Sinyal ini memperlihatkan adanya osilasi seperti rangkaian listrik akibat ketakstabilan populasi elektTon yang dipengaruhi oleh parameter relaksasi elektron pada aras tenaga tersebut."
JURFIN 11:26 (2005)
Artikel Jurnal  Universitas Indonesia Library
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Satyani Maria Ratni
"Lipstik adalah sediaan kosmetika yang dibubuhi zat warna, dalam hal ini yang berperan adalah warna lipstik, untuk memberikan warna dan bentuk yang menarik pada bibir. Banyak lipstik yang beredar diduga mengandung zat warna terlarang maupun zat warna dengan kadar melebihi . batas yang ditetapkan. Pada penelitian ini akan diperiksa zat warna tersebut secara kualitatif dan kuantitatif menggunakan metode gabungan Kromatografi Lapis Tipis (KLT)- Kromatografi Cair Kinerja Tinggi (KCKT). Lipstik digoreskan secara langsung pada lempeng KLT Silica gel 60 (tanpa indikator fluore sensi). Minyak-minyak, malam-malam serta zat warna Permaton Red dan Permanent Orange dipisahkan dengan pengembangan berulang-ulang menggunakan diklormetan (pelarut KLTA). Pita-pita zat warna di bawah malam-malam dan minyak-minyak dikikis dari lempeng dan dilarutkan dalam diklormetan. Zat warna Tetrabromofluorescein dan Rhodamine B Stearate yang tersisa pada garis dasar dikembangkan menggunakan pelarut KLTB yaitu campuran etilasetat ammonia-air (3:7):metanol (15:3:3). Pita-pita zat warna dan garis dasar dikikis dari lempeng dan dilarutkan dalam campuran metanol-0,01 M TBAH-asam asetat (70:29:1). KCKT dilakukan pada kolom Spherisorb-ODS (30 em x 4,6 mm) dengan kecepatan aliran 1,0 ml/menit ; attenuasi, 2; dan kecepatan kertas, 5 mm/menit. Permaton Red dan Permanent Orange dapat dianalisis menggunakan campuran metanol-air-asam asetat (89 :10:1 ) sebagai fase gerak dan di deteksi pada 405 nm sedang Rhodamine B Stearate dan Tetrabromofluorescein dapat dianalisis menggunakan campuran metanol-0,01 M TBAH pH 3,5 (yang diperoleh dengan penambahan asam fosf at)-asam asetat (70:29:1) sebagai fase gerak dan dideteksi pada 546 nm. Dari penelitian ini diperoleh bahwa lipstik berwarna jingga kemerahan tidak mengandung Permanent Orange dan Permaton Red ; lipstik berwarna merah muda keu nguan tidak mengandung Rhodamine B Stearate dan Tetrabromofluorescein."
Depok: Fakultas Matematika dan Ilmu Pengetahuan Alam Universitas Indonesia, 1995
S32007
UI - Skripsi Membership  Universitas Indonesia Library
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Praditya Nugraha
"Fenomena localized surface plasmon resonance (LSPR) pada nanowire memiliki dua mode eksitasi berbeda yang sangat bergantung pada polarisasi gelombang eksitasinya, yaitu mode polarisasi longitudinal (mode transverse electric) dan mode polarisasi transversal (mode transverse magnetic). Kedua mode eksitasi masing – masing memiliki karakteristik yang unik. Mode transverse electric memiliki pola spektra LSPR dengan beberapa puncak resonansi yang terpisah jelas dan dapat dibedakan, sedangkan mode transverse magnetic hanya memiliki puncak resonansi tunggal pada frekuensi tinggi. Pada penelitian ini, akan dilakukan pemodelan spektra LSPR nanowire perak dengan beberapa variasi bentuk dan ukuran. Fungsi dielektrik perak diperoleh dari penelitian Johnson dan Christy (1972). Ada dua jenis nanowire yang dimodelkan: nanowire dengan tutup ujung rata (flat) dan tutup ujung setengah bola (hemi-spherical). Untuk mengetahui pengaruh perubahan bentuk dan ukuran nanopartikel, pemodelan yang dilakukan menggunakan nanowire dengan diameter 10, 30, dan 50 nanometer serta aspect ratio sebesar 10, 12, 14, 16, 18, dan 20. Hasil pemodelan mode TE menunjukkan spektra LSPR dengan beberapa puncak resonansi yang terpisah jelas. Banyaknya puncak resonansi ini diduga berasal dari adanya interferensi konstruktif gelombang berdiri surface plasmon polariton (SPP) pada nanowire. Berbeda dengan prediksi awal, hasil pemodelan mode TM menunjukkan dua buah puncak resonansi. Kedua puncak resonansi ini dapat dikaitkan dengan osilasi plasmon mode transversal dan longitudinal pada nanowire.

The localized surface plasmon resonance (LSPR) phenomenon on nanowires possess two distinct excitation modes that depend on the polarization of the exciting planewave, the longitudinal polarization mode (transverse electric mode) and the transversal polarization mode (transverse magnetic mode). Both excitation modes exhibit unique optical spectra characteristics. The optical spectra of the transverse electric mode exhibit multiple, wellseparated resonance peaks while the optical spectra of the transverse magnetic mode only exhibit a single resonance peak spectrally located at a high frequency. In this study, we have simulated the optical LSPR spectra of silver nanowires with several size variations. The dielectric function of silver was obtained through Johnson and Christy’s previous work (1972). Two nanowire types with different end-cap shapes on each end were simulated: one having a flat end-cap shape and the other having a hemi-spherical end-cap shape. In order to discover the effects of nanoparticle size change, the simulation was done on nanowires with diameters 10, 30, and 50 nanometers along with aspect ratios of 10, 12, 14, 16, 18, and 20. The TE mode simulations result in an optical spectrum exhibiting multiple, well-separated resonance peaks. These multiple peaks are assumed to arise from the constructive interference of surface plasmon polaritons (SPPs) excited on the surface of the nanowire. Unlike previous observations, the TM mode simulations result in an optical spectrum which exhibit two resonance peaks. Both peaks can be attributed to the transversal and longitudinal plasmon oscillations which occur on the nanowire."
Depok: Fakultas Matematika dan Ilmu Pengetahuan Alam Universitas Indonesia, 2020
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UI - Skripsi Membership  Universitas Indonesia Library
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Indriyanti Novitasari
"Pada penelitian ini telah berhasil disintesis Z-scheme heterojunction nanokomposit rGO/CeO2-BiVO4 yang digunakan sebagai fotokatalis dalam mendegradasi zat warna rhodamine b. Penggunaan rGO bertujuan sebagai mediator transfer elektron oleh dua semikonduktor CeO2 dan BiVO4. Keberhasilan sintesis nanopartikel CeO2, BiVO4, komposit CeO2–BiVO4 dan nanokomposit rGO/CeO2–BiVO4 didukung dengan energy band gap masing-masing 3,15 eV, 2,45 eV, 2,27 eV dan 2,30 eV. Hasil morfologi SEM menunjukkan terdapat nanokomposit CeO2–BiVO4 yang tersebar diatas permukaan rGO dan TEM diperoleh ukuran partikel rata-rata komposit CeO2–BiVO4 yang berada pada permukaan rGO adalah 18,3782 nm. Aktivitas fotokatalitik rGO/CeO2–BiVO4 terhadap degradasi rhodamine b diperoleh paling optimum sebesar 95,88% dalam waktu 40 menit dibawah sinar tampak. Kinetika reaksi terhadap degradasi rhodamine b mengikuti model kinetika pseudo orde satu dan isoterm adsorpsi Langmuir yang menunjukkan bahwa proses yang terjadi merupakan fotokatalisis. Mekanisme Z–Scheme Heterojunction pada nanokomposit rGO/CeO2–BiVO4 berhasil diusulkan didukung dengan peningkatan aktivitas fotokatalitik degradasi rhodamine b dibandingkan dengan material penyusunnya. Pengembangan fotokatalis berbasis mekanisme Z-Scheme Heterojunction yang memiliki aktivitas fotokatalitik yang baik dapat dipertimbangkan pada penelitian selanjutnya.

In this study, Z-scheme heterojunction nanocomposite rGO/CeO2-BiVO4 was successfully synthesized and used as a photocatalyst in degradation of rhodamine b dyes. The use of rGO is intended as an electron mediator of two CeO2 and BiVO4 semiconductors. The success of the synthesis of CeO2 nanoparticles, BiVO4, CeO2–BiVO4 composites and rGO/CeO2–BiVO4 nanocomposites was supported by energy band gaps of 3.15 eV, 2.45 eV, 2.27 eV and 2.30 eV, respectively. SEM morphology results showed that there were CeO2–BiVO4 nanocomposites spread over the surface of rGO and TEM results obtained the average particle size of CeO2–BiVO4 composites on the rGO surface was 18.3782 nm. The photocatalytic activity of rGO/CeO2–BiVO4 achieving the degradation efficiencies of 95.88% within 40 minutes under visible light. The reaction kinetics on the degradation of rhodamine b followed the pseudo-first-order kinetics model and the Langmuir adsorption isotherm which showed that the process was photocatalytic reaction. The Z–Scheme Heterojunction mechanism in the rGO/CeO2–BiVO4 nanocomposite was successfully proposed, supported by the increased photocatalytic activity of rhodamine b degradation compared to the pure CeO2 or BiVO4. Finally, the development of a photocatalyst based on the Z-Scheme Heterojunction mechanism with a great photocatalytic activity can be considered in further research."
Depok: Fakultas Matematika dan Ilmu Pengetahuan Alam Universitas Indonesia, 2022
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UI - Skripsi Membership  Universitas Indonesia Library
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Moto, Keba
"Substitusi Atom Ti dengan Al dalam kristal TiN untuk membentuk paduan (Ti1-xAlx)N sangat jelas diperagakan dari lapisan tipis yang dideposisi di atas substrat stainless steel dengan menggunakan teknik plasma CVD. Adanya atom Al dalam kristal TiN ditunjukkan dengan XRD dan EDX: penurunan konstanta kisi TiN sesuai dengan kenaikan fraksi Al (XRD) dan presipitasi fase hexagonal AlN (XRD) ketika fraksi Al melewati 0,8 (EDX). Kekerasan lapisan tipis ini hanya sekitar 30 GPa, yang melebihi hasil-hasil yang ada dalam literatur.

The substitution of Ti atoms by Al atoms in TiN lattice sites to form (Ti1-xAlx)N is clearly demonstrated by the coatings which were deposited on steel substrate and using plasma CVD technique. The presence of Al atoms in TiN lattice site is shown by means of XRD and EDX techniques: lattice parameters decreasing of TiN as the fraction of Al increases (XRD) and precipitation of hexagonal AlN phase (XRD) as the fraction of Al exceeding 0.8 (EDX). The hardness of these coating are just around 30 GPa, which is beyond the values reported in literatures."
Depok: Lembaga Penelitian Universitas Indonesia, 2002
AJ-Pdf
Artikel Jurnal  Universitas Indonesia Library
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Nabila Anisa
"Pencemaran limbah cair industri zat warna di Indonesia telah menjadi permasalahan lingkungan yang serius. Beberapa metode yang digunakan untuk mengatasi limbah zat warna diantaranya filtrasi membran, ozonisasi, klorinasi, proses elektrokimia, fotodegradasi, koagulasi flokulasi, oksidasi kimia, oksidasi biologi, dan adsorpsi. Adsorpsi memilki kelebihan yaitu berbagai macam bahan adsorben, preparasi dan operasi mudah, nilai ekonomis tinggi, efisiensi tinggi, reusabilitas baik, cocok untuk beragam zat warna ramah lingkungan dan dapat digunakan untuk menghilangkan pewarna organik dalam perairan dengan skala besar. Beragam adsorben dengan struktur pori dan luas permukaan spesifik telah dipelajari, salah satunya MOFs. MOFs memiliki keunggulan seperti luas permukaan spesifik yang tinggi, porositas yang baik, dan ukuran pori terkontrol. Dalam penelitian ini MOFs jenis MIL-101 (Fe) disintesis menggunakan logam Fe yang ramah lingkungan dan ligan BDC dengan metode solvothermal. Variasi suhu 100oC dan 120oC, jumlah prekursor FeCl3.6H2O 2,45 mmol, 4,9 mmol, dan 9,81 mmol dan jenis pelarut yaitu DMF dan campuran pelarut DMF : Aquades dengan perbandingan 2 : 3 dipelajari pengaruhnya terhadap sintesis MOF, MOF hasil sintesis kemudian diaplikasikan sebagai adsorben zat warna Methylene Blue dan Rhodamine B dalam air. Hasil sintesis dikarakterisasi menggunakan FTIR, XRD, TGA, BET, dan SEM untuk mengetahui ikatan kimia, topologi kerangka, kristanilitas, luas permukaan, dan stabilitas termal. Hasil karakterisasi menunjukan variasi suhu dan prekusor dihasilkan MOF dengan struktur polimorfik MIL-88B. Aplikasi adsorpsi zat warna Methylene Blue dan Rhodamine mencapai kapasitas absorpsi optimum pada pH 9 dan waktu kontak 180 menit adsorpsi Fe-BDC MOF pada Methylene Blue dan Rhodamine B mengikuti pemodelam isoterm adsorpsi Langmuir dengan kapasitas adsorpsi maksimum berturut-turut sebesar 162,82 mg/g dan144,65 mg/g.
Kata Kunci: Fe-Metal Organic Frameworks, Methylene Blue, Rhodamine B, Adsorpsi, Ligan BDC (Asam 1,4-benzena dikarboksilat), metode solvothermal.
The industrial dye-wastewater has been a tremendous environmental problem in Indonesia. Several techniques have been used to eliminate dye-waste water, such as membrane filtration, chlorinaton, ozonation, coagulation-floculation, chemical oxidation, biology oxidation, and adsorption. Adsorption technique is extensively used for removal of the dye-wastewater due the excellent properties of its method, having various of adsorbent material, simple preparation and operation, low cost, high efficiency, good reusability and capable of reducing the organic dyes widely. In this case, many adsorbents, having tunable pore and specific surface area, have been studied. MOFs have some advantages as adsorbents in that their large surface area, tunable pore size, and adjustable porosity. In this work, MOFs type MIL-101 (Fe) was synthesized assisted solvothermal reactions at 100 oC and 120 oC, and various amount of FeCl3.6H2O precursor of 2.45 mmol, 4.9 mmol, and 9.81 mmol. The effect of solvents in the synthesis was studied by using DMF and mixture of DMF: distilled water 3 : 2. Briefly, MIL-101 was synthesized with environmental friendly metal precursor, FeCl3.6H2O, and 1,4 benzenedicarboxylate (BDC) ligands. The material characteristics of the as-synthesized Fe-BDC MOF such as structure and topology of MOFs, surface area, and thermal stability were studied using XRD, FTIR, BET, TGA, and SEM. The XRD patterns show that the crystals of MIL101 was successfully formed with some impurities of MIL-88B. The application of Fe-BDC MOF as adsorbent for Methylene Blue (MB) and Rhodamine B (RhB) in aqueous solution is learned. The optimum adsorption condition showed when 5 mg Fe-BDC MOF is applied to the dyes after 180 minutes at pH 9. It was found that the isotherm data for Methylene Blue and Rhodamine B had a good correlation with the Langmuir isotherm. The maximum adsorption capacity of MOF was able to reach 162,82 mg/g for Methylene Blue and 144,65 mg/g for Rhodamine B.
Keyword(s): Fe-Metal Organic Frameworks, Methylene Blue, Rhodamine B, adsorption, 1,4 benzenedicarboxylate (BDC), and solvothermal method.
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Depok: Fakultas Matematika dan Ilmu Pengetahuan Alam Universitas Indonesia, 2020
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