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Abstrak :
Telah dilakukan penelitian pengaruh tekanan terhadap konstanta kisi dan konstanta dielektrik untuk material Barium Titanat dan Kuarsa sampai 2,13 x 109 Pa. Harga konstanta kisi tanpa tekanan untuk Barium Titanat adalah a = 3,99 dan c = 4,04Å dan untuk Kuarsa a = 4,91 dan c= 5,40 Å. Untuk kedua material tersebut harga konstanta kisi berbanding terbalik dengan tekanan yang diberikan. Harga konstanta dielektrik Barium Titanat tanpa tekanan adalah 1243. Harga konstanta dielektrik maksimum sebesar 16900 didapatkan pada tekanan transisi sekitar 1,79 x 109 Pa. di atas tekanan ini harga, konstanta dielektrik akan menurun kembali. Sedangkan pada Kuarsa harga konstanta dielektrik menur un dengan naiknya tekanan.

Abstrak :
[ABSTRAK
Fe-Cr adalah paduan yang memiliki ketahanan temperatur tinggi dan potensial digunakan sebagai interkonektor pada sel bakar (SOFC=solid oxide fuel cell). Sintesis paduan Fe-Cr terus dikembangkan untuk mendapatkan metode yang efektif, dan efisien. Metode sintesis paduan Fe-Cr yang ada sekarang ini adalah metode peleburan, metalurgi serbuk ataupun metode pemaduan mekanik. Metodemetode tersebut memiliki kelemahan misalnya paduan yang tidak homogen, terdapat oksida, proses panjang dan membutuhkan waktu lama. Untuk meminimumkan permasalahan ini, adalah penting untuk menghasilkan paduan mikro Fe-Cr yang memiliki kestabilan fasa dan sifat mekanis baik. Metode ultrasonik dapat dimanfaatkan untuk sintesis paduan mikro homogen melalui penggunaan gelombang suara ultrasonik. Gelombang suara ultrasonik menghasilkan gelembung-gelembung kavitasi, setiap runtuhan kavitasi dapat dianggap sebagai reaktor mikro yang mampu menghasilkan temperatur sekitar 4737 oC dan tekanan sekitar 1000 atm dan yang terbentuk dengan sangat cepat, serta menghasilkan gelombang kejut. Dengan demikian metode ultrasonik dapat dimanfaatkan dalam pembuatan paduan mikro Fe-Cr yang homogen serta tanpa oksida dan diharapkan bisa mengatasi kelemahan metode pembuatan paduan berbasis Fe saat ini. Pada penelitian ini telah dilakukan sintesis paduan mikro Fe- Cr dengan metode ultrasonik pada frekuensi 20 kHz dalam cairan toluene. Tahapan yang telah dilakukan adalah perlakuan ultrasonik sebagai variasi waktu terhadap partikel prekursor (Fe, Cr), kemudian terhadap campuran partikel precursor untuk mendapatkan paduan mikro Fe-Cr. Kemudian dilakukan pembuatan bongkah paduan Fe-Cr dari partikel hasil perlakuan ultrasonik melalui kompaksi tanpa lubrikan dan sintering dalam kapsul kaca kuarsa. Karakterisasi yang dilakukan adalah menggunakan Scanning Electron Microscopy (SEM) terhadap partikel precursor hasil rekayasa ultrasonic. Untuk partikel campuran prekursor Fe-Cr hasil perlakuan ultrasonik karakterisasi dilakukan menggunakan SEM-EDS (Energy Dispersive Spectroscopy), X-Ray Diffraction (XRD) disertai analisis dengan metode Rietveld, Transmission Electron Microscopy-Selected Area Electron Diffraction (TEM-SAED). Untuk bongkah Fe-Cr hasil konsolidasi dengan menggunakan SEM-EDS, XRD disertai analisis dengan metode Rietveld, pengukuran densitas sebenarnya, pengujian kekerasan Vickers. Efek perlakuan ultrasonik terhadap partikel Fe adalah pengurangan ukuran, penyatuan, dan aglomerasi. Setelah perlakuan ultrasonik 40 jam terjadi peningkatan ukuran partikel Fe (>2μm). Terhadap partikel Cr memberikan efek erosi permukaan, pengurangan ukuran dan pemecahan partikel aglomerasi. Partikel Cr aglomerasi terurai sepenuhnya menjadi partikel Cr kecil (< 2 m) setelah 63 jam. Terhadap campuran partikel Fe dan Cr dapat menyatukan partikel kohesif (Fe-Fe, Cr-Cr) dan adhesif (Fe-Cr), terbentuk paduan mikro Fe-Cr seutuhnya (setelah 20 jam) ataupun paduan mikro Fe-Cr sebagian (setelah 50 jam). Pembentukan paduan mikro Fe-Cr diawali pada ukuran partikel Fe ataupun Cr < 2m. Bongkah paduan mikro Fe-Cr yang diperoleh adalah homogen dan tanpa oksida, dengan karakteristik densitas melalui sintering dua tahap yaitu tipe O = 8.655 gr/cm3, tipe B=8.179 gr/cm3, dan tipe A=8.196 gr/cm3, dan melalui proses sintering satu tahap tipe O = 7.678 gr/cm3, tipe B=7.587gr/cm3, dan tipe A=7.092 gr/cm3. Kekerasan bongkah Fe-Cr terbesar melalui sintering satu tahap yaitu 88 VHN adalah tipe B, sementara terbesar dua tahap yaitu 81 VHN adalah tipe A. Proses perlakuan ultrasonik memberikan dampak positif baik dari sisi waktu proses maupun kualitas hasil paduan Fe-Cr. Dengan demikian metode ultrasonik bisa diandalkan sebagai alternatif dalam pembuatan paduan berbasis Fe untuk mengatasi kendala homogenisasi dan oksidasi yang dihadapi pada metode saat ini.;

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ABSTRACT
Fe-Cr alloys have the potential for use as an interconnection material for solid oxide fuel cell (SOFC) due to its being resistance to high temperatures. Synthesis methods of Fe-Cr alloy continue to be developed in order to obtain a method that is both effective and efficient. Presently, the synthesis of Fe-Cr alloys include the casting, the powder metallurgy, and the mechanical alloying method. These methods have several drawbacks such as inhomogeneity in the resulting products, oxidation, and require a very time-consuming process to accomplish. In order to minimize this problem, it is important to produce Fe-Cr microalloys. Fe- Cr microalloys exhibit phase stability and good mechanical properties. Ultrasonic methods can be used in the synthesis of homogeneous microalloys by employing the ultrasonic sound waves. Ultrasonic sound waves will generate cavitation bubbles. Any cavitation collapse can be considered as a micro reactor in which a temperature of about 4737 oC and a pressure of about 1000 atm a very rapidly created, thereby generating a shock wave. Thus, the ultrasonic method can be used in producing homogeneous and free-oxide Fe-Cr microalloys and can be expected to overcome the limitations imposed by the current methods. In this work the formation of Fe-Cr microalloys by ultrasonic treatment at a frequency of 20 kHz in toluene liquid is presented. In the synthesis procedure, the procedure steps followed were: (1) the treatment of precursor particles (Fe, Cr) through ultrasonic method with a time-variation, followed by (2) the same time-varying ultrasonic treatment on the admixture of these specially prepared precursor particles in order to obtain the Fe-Cr microalloys, and (3) finally, the lubricantless compaction method was employed on these precursor particles admixture followed by sintering process inside quartz tubes to obtain a bulk of Fe-Cr alloy. Observations of the specially prepared precursor particles using ultrasonic technique were carried out by scanning electron microscopy (SEM) method. Observation of the precursor mixture of Fe-Cr particles mixture treated ultrasonically was performed using a SEM-EDS (energy-dispersive spectroscopy) apparatus, a X-Ray diffractometer and accompanied by the Rietveld analysis method, and transmission electron microscopy (TEM)-selected area electron diffraction (SAED) apparatus. The bulk of Fe-Cr alloy were observed using SEMEDS, XRD accompanied by analysis by the Rietveld method, true density measurement, and Vickers microhardness testing. Ultrasonic treatment has caused Fe particles to form agglomerations, an interparticles neck formation, and a fusing among the particles. The size of the Fe particles increased (>2μm) after 40 hours treatment. The agglomerated Cr particles experienced fragmentation, surface erosion, and reduction of particle size. The agglometrated Cr particles fully disintegrated into Cr microparticles (<2μm) after 63 hours treatment. The mixture of Fe-Cr forming cohesive (Fe-Fe, Cr-Cr) and adhesive (Fe-Cr) particles, forming completely (after ultrasonic treatment for 20 hours) and partially (after ultrasonic treatment for 50 hours) Fe-Cr microalloys. The complete formation of Fe-Cr microalloy was possible with an equal particle size of the precursor Fe and Cr (approximately <2 μm). The bulk of Fe-Cr alloy results are homogenous and oxide-free. For two-step sintering, its density (in gr/cm3 unit) is 8.655 for type O, is 8.179 for type B, and is 8.196 for type A, and for one-step sintering its density is 7.678 for type O, is 7.587 for type B, and is 7.092 for type A. The greatest microhardness number of 88 VHN is of type B (one-step sintering), and of 81 VHN is of type A (two-step sintering). The ultrasonic treatment process has a positive impact, with respect to both of quality and time-consumption to finish the Fe-Cr alloying process. Therefore the ultrasonic method can be relied upon as an alternative method in the production of Fe-based alloys to solve problems in homogenization and oxidation encountered in current methods;Fe-Cr alloys have the potential for use as an interconnection material for solid oxide fuel cell (SOFC) due to its being resistance to high temperatures. Synthesis methods of Fe-Cr alloy continue to be developed in order to obtain a method that is both effective and efficient. Presently, the synthesis of Fe-Cr alloys include the casting, the powder metallurgy, and the mechanical alloying method. These methods have several drawbacks such as inhomogeneity in the resulting products, oxidation, and require a very time-consuming process to accomplish. In order to minimize this problem, it is important to produce Fe-Cr microalloys. Fe- Cr microalloys exhibit phase stability and good mechanical properties. Ultrasonic methods can be used in the synthesis of homogeneous microalloys by employing the ultrasonic sound waves. Ultrasonic sound waves will generate cavitation bubbles. Any cavitation collapse can be considered as a micro reactor in which a temperature of about 4737 oC and a pressure of about 1000 atm a very rapidly created, thereby generating a shock wave. Thus, the ultrasonic method can be used in producing homogeneous and free-oxide Fe-Cr microalloys and can be expected to overcome the limitations imposed by the current methods. In this work the formation of Fe-Cr microalloys by ultrasonic treatment at a frequency of 20 kHz in toluene liquid is presented. In the synthesis procedure, the procedure steps followed were: (1) the treatment of precursor particles (Fe, Cr) through ultrasonic method with a time-variation, followed by (2) the same time-varying ultrasonic treatment on the admixture of these specially prepared precursor particles in order to obtain the Fe-Cr microalloys, and (3) finally, the lubricantless compaction method was employed on these precursor particles admixture followed by sintering process inside quartz tubes to obtain a bulk of Fe-Cr alloy. Observations of the specially prepared precursor particles using ultrasonic technique were carried out by scanning electron microscopy (SEM) method. Observation of the precursor mixture of Fe-Cr particles mixture treated ultrasonically was performed using a SEM-EDS (energy-dispersive spectroscopy) apparatus, a X-Ray diffractometer and accompanied by the Rietveld analysis method, and transmission electron microscopy (TEM)-selected area electron diffraction (SAED) apparatus. The bulk of Fe-Cr alloy were observed using SEMEDS, XRD accompanied by analysis by the Rietveld method, true density measurement, and Vickers microhardness testing. Ultrasonic treatment has caused Fe particles to form agglomerations, an interparticles neck formation, and a fusing among the particles. The size of the Fe particles increased (>2μm) after 40 hours treatment. The agglomerated Cr particles experienced fragmentation, surface erosion, and reduction of particle size. The agglometrated Cr particles fully disintegrated into Cr microparticles (<2μm) after 63 hours treatment. The mixture of Fe-Cr forming cohesive (Fe-Fe, Cr-Cr) and adhesive (Fe-Cr) particles, forming completely (after ultrasonic treatment for 20 hours) and partially (after ultrasonic treatment for 50 hours) Fe-Cr microalloys. The complete formation of Fe-Cr microalloy was possible with an equal particle size of the precursor Fe and Cr (approximately <2 μm). The bulk of Fe-Cr alloy results are homogenous and oxide-free. For two-step sintering, its density (in gr/cm3 unit) is 8.655 for type O, is 8.179 for type B, and is 8.196 for type A, and for one-step sintering its density is 7.678 for type O, is 7.587 for type B, and is 7.092 for type A. The greatest microhardness number of 88 VHN is of type B (one-step sintering), and of 81 VHN is of type A (two-step sintering). The ultrasonic treatment process has a positive impact, with respect to both of quality and time-consumption to finish the Fe-Cr alloying process. Therefore the ultrasonic method can be relied upon as an alternative method in the production of Fe-based alloys to solve problems in homogenization and oxidation encountered in current methods, Fe-Cr alloys have the potential for use as an interconnection material for solid oxide fuel cell (SOFC) due to its being resistance to high temperatures. Synthesis methods of Fe-Cr alloy continue to be developed in order to obtain a method that is both effective and efficient. Presently, the synthesis of Fe-Cr alloys include the casting, the powder metallurgy, and the mechanical alloying method. These methods have several drawbacks such as inhomogeneity in the resulting products, oxidation, and require a very time-consuming process to accomplish. In order to minimize this problem, it is important to produce Fe-Cr microalloys. Fe- Cr microalloys exhibit phase stability and good mechanical properties. Ultrasonic methods can be used in the synthesis of homogeneous microalloys by employing the ultrasonic sound waves. Ultrasonic sound waves will generate cavitation bubbles. Any cavitation collapse can be considered as a micro reactor in which a temperature of about 4737 oC and a pressure of about 1000 atm a very rapidly created, thereby generating a shock wave. Thus, the ultrasonic method can be used in producing homogeneous and free-oxide Fe-Cr microalloys and can be expected to overcome the limitations imposed by the current methods. In this work the formation of Fe-Cr microalloys by ultrasonic treatment at a frequency of 20 kHz in toluene liquid is presented. In the synthesis procedure, the procedure steps followed were: (1) the treatment of precursor particles (Fe, Cr) through ultrasonic method with a time-variation, followed by (2) the same time-varying ultrasonic treatment on the admixture of these specially prepared precursor particles in order to obtain the Fe-Cr microalloys, and (3) finally, the lubricantless compaction method was employed on these precursor particles admixture followed by sintering process inside quartz tubes to obtain a bulk of Fe-Cr alloy. Observations of the specially prepared precursor particles using ultrasonic technique were carried out by scanning electron microscopy (SEM) method. Observation of the precursor mixture of Fe-Cr particles mixture treated ultrasonically was performed using a SEM-EDS (energy-dispersive spectroscopy) apparatus, a X-Ray diffractometer and accompanied by the Rietveld analysis method, and transmission electron microscopy (TEM)-selected area electron diffraction (SAED) apparatus. The bulk of Fe-Cr alloy were observed using SEMEDS, XRD accompanied by analysis by the Rietveld method, true density measurement, and Vickers microhardness testing. Ultrasonic treatment has caused Fe particles to form agglomerations, an interparticles neck formation, and a fusing among the particles. The size of the Fe particles increased (>2μm) after 40 hours treatment. The agglomerated Cr particles experienced fragmentation, surface erosion, and reduction of particle size. The agglometrated Cr particles fully disintegrated into Cr microparticles (<2μm) after 63 hours treatment. The mixture of Fe-Cr forming cohesive (Fe-Fe, Cr-Cr) and adhesive (Fe-Cr) particles, forming completely (after ultrasonic treatment for 20 hours) and partially (after ultrasonic treatment for 50 hours) Fe-Cr microalloys. The complete formation of Fe-Cr microalloy was possible with an equal particle size of the precursor Fe and Cr (approximately <2 μm). The bulk of Fe-Cr alloy results are homogenous and oxide-free. For two-step sintering, its density (in gr/cm3 unit) is 8.655 for type O, is 8.179 for type B, and is 8.196 for type A, and for one-step sintering its density is 7.678 for type O, is 7.587 for type B, and is 7.092 for type A. The greatest microhardness number of 88 VHN is of type B (one-step sintering), and of 81 VHN is of type A (two-step sintering). The ultrasonic treatment process has a positive impact, with respect to both of quality and time-consumption to finish the Fe-Cr alloying process. Therefore the ultrasonic method can be relied upon as an alternative method in the production of Fe-based alloys to solve problems in homogenization and oxidation encountered in current methods]

Abstrak :
ABSTRACT
Meningkatnya luas permukaan kedap air seperti lahan parkir menyebabkan berkurangnya infiltrasi alami ke dalam tanah sehingga berdampak pada meningkatnya volume limpasan air hujan. Limpasan air hujan mengandung berbagai macam polutan seperti logam berat, nutrien, organik maupun sedimen. Konsentrasi logam berat dan nutrien amonia yang terkandung dalam limpasan di lahan parkir mobil FTUI telah melebihi baku mutu berdasarkan Peraturan Pemerintah No. 82 Tahun 2001, yaitu Pb, Zn dan NH3 masing ndash;masing 0,73 mg/L, 0,39 mg/L dan 3,7 mg/L. Bioretensi merupakan salah satu LID yang dapat mengolah limpasan air hujan. Untuk meningkatkan efisiensi penyisihan pada bioretensi, maka dilakukan kombinasi pada media filter. Penelitian menggunakan 3 reaktor bioretensi skala pilot berukuran 30 30 80 cm3 dan tanaman Iris pseudacorus untuk mengetahui efisiensi penyisihan Pb, Zn dan NH3. Variasi komposisi media filter yang terdiri dari pasir kuarsa dan zeolit dibedakan pada setiap reaktor dengan perbandingan 1:3, 1:1, 3:1 berurut dari reaktor 1,2, dan 3. Setelah 5 kali pengaliran synthetic runoff dengan konsentrasi berbeda, hasil menunjukkan bahwa variasi konsentrasi influen memiliki pengaruh yang kecil yaitu 20-40 terhadap persentase penyisihan logam berat dan amonia. Rata-rata efisiensi penyisihan bioretensi 1, 2 dan 3 berturut ndash;turut yaitu 91, 78, 83 untuk Pb, 88, 95, 94 untuk Zn dan 97, 98, 96 untuk NH3. Kombinasi media filter pasir kuarsa dan zeolit terbukti meningkatkan efisiensi penyisihan sebesar 11,5 untuk NH3, 18 Pb dan 20 Zn yang dibandingkan dengan penelitian sebelumnya. Tanaman menyerap polutan sebesar 18 dengan akar menyerap 9-14 kali lebih besar daripada daun, sedangkan media filter menyerap 70 polutan. Bioretensi dengan komposisi 35 pasir kuarsa, 40 zeolit, 10 tanah dan 10 kompos serta Iris pseudacorus diusulkan sebagai kombinasi media filter dengan kinerja terbaik untuk peningkatan efisiensi penyisihan.

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ABSTRACT
Increasing impervious surface areas such as parking lots cause a reduction in natural infiltration into the soil, resulting in an increase in stormwater runoff volume. Stormwater runoff contains a variety of pollutants such as heavy metals, nutrients, organic and sediments. The concentration of heavy metals and nutrients ammonia contained in stormwater runoff in FTUI rsquo s car park has exceeded the quality standard of Government Regulation No. 82 of 2001, such as Pb, Zn and NH3 approximately 0,73 mg L 0,39 mg L and 3,7 mg L, respectively. Bioretention is one of the LID that can affecting treat stormwater runoff. To increase removal efficiency on bioretention, a combination of filter media is applied. Observation was conducted on a pilot scale using three reactor each 30 30 80 cm3 and Iris pseudacorus as plant to determine removal efficiency of Pb, Zn and NH3. Variation of filter media composition consists of quartz sand and zeolite with ratio 1 3, 1 1, 3 1, on bioretention 1, 2 and 3, respectively. After 5 times running of synthetic runoff with different concentration, the results showed that variations in influent concentrations has a small effect of 20 40 on the removal efficiency of heavy metals and ammonia. The average removal efficiency of bioretention 1, 2 and 3 for Pb was 91, 78, 83, respectively, followed 88, 95, 94 for Zn and 97, 98, 96 for NH3. The combination of quartz sand and zeolite as filter media proved to increase the removal efficiency by 11,5 for NH3, 18 Pb and 20 Zn compared to previous research. The plants absorb pollutants by 18 with roots absorbing 9 14 times larger than leaves, while filter media absorbing 70 pollutants. Bioretention with a combination of filter media with composition of 35 quartz sand, 40 zeolite, 10 soil, 10 compost and Iris pseudacorus is proposed to have best performance to increasing removal efficiency.

Abstrak :
Pembuatan polikristal Copper Galium Diselenide (CuGaSe2) telah dilakukan dengan menggunakan tungku horizontal zona temperatur tunggal. Unsur-unsur penyusun dicampur, dilelehkan dan selanjutnya didinginkan sehingga menghasilkan polikristal. Kristal yang dihasilkan dikarakterisasi meliputi identifikasi struktur menggunakan XRD (X Ray Diffraction), analisis reaksi kimia selama penumbuhan menggunakan DTA (Differensial Thermal Analysis) dan komposisi unsur menggunakan SEM (Scanning Electron Microscopy). Kristal yang dihasilkan secara visual cukup baik dan tidak menempel pada dinding ampoule. Struktur kristal sampel adalah chalcopyrite. Berdasarkan pengukuran diperoleh nilai parameter kisi ingot a=b, secara berurutan untuk ingot bagian atas, tengah dan bawah adalah 5,613 A; 5,612 A dan 5,615 A; dan nilai c adalah 11,014 A; 10,992 A dan 11,013 A.

Abstrak :
Kamper merupakan sumber karbon yang dapat diperbaharui untuk digunakan sebagai bahan baku didalam sintesis CNT. Kamper merupakan zat yang dapat ditemukan pada pohon Cinnamomum camphora. Dalam penelitian ini, metode yang digunakan untuk mensintesis ACNT dari kamper adalah Floating Catalyst Chemical Vapor Deposition (FC-CVD) dengan katalis Ferrocene pada suhu 800oC dan gas hidrogen sebagai ko-reaktan serta gas argon sebagai carrier gas. Metode ini merupakan metode paling populer dalam mensintesis ACNT yang terorientasi dan memiliki densitas tinggi. Kamper akan terdekomposisi menjadi senyawa benzena, toluena, dan xylena pada suhu 800oC. Dengan menggunakan uji karakterisasi GC-FID, hasil penelitian menunjukkan dekomposisi kamper pada suhu 800oC didominasi oleh senyawa benzena dengan konsentrasi sebesar 92,422-97,656%. Penelitian dilakukan, dengan memvariasikan laju alir carrier gas berupa argon sebesar 40, 55, 70, 85 dan 100 mL/ menit pada suhu 800oC selama 60 menit waktu reaksi. Laju alir carrier gas argon sebesar 70 mL/ menit menghasilkan yield yang terbaik, namun hal ini tidak diikuti oleh kualitas CNT yang terbaik. Kualitas CNT yang terbaik diperoleh pada laju alir carrier gas argon sebesar 55 mL/ menit berdasarkan hasil uji karakterisasi SEM, EDX, Mapping, dan Spektroskopi RAMAN. Penelitian ini belum memperoleh CNT dengan bentuk aligned (ACNT).

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Camphor is a renewable carbon source that can be used as raw material for synthesizing CNT. Camphor is a substance that can be found on the Cinnamomum camphora tree. In this research, the method used to synthesize ACNT from camphor is Floating Catalyst Chemical Vapor Deposition (FC-CVD) with Ferrocene as catalyst at temperature of 800oC, hydrogen gas as the co-reactant and argon gas as carrier gas. This method is the most popular method of synthesizing ACNT which oriented and have a high density. Camphor decomposes into benzene, toluene, and xylene at a temperature of 800oC. By using GC-FID for characterization test, the results showed decomposition at a temperature of 800oC camphor dominated by benzene with a concentration of 92.422 to 97.656%. The research was conducted by varying the flow rate of carrier gas such as argon at 40, 55, 70, 85 and 100 mL / min at a temperature of 800oC for 60 minutes of reaction time. Argon carrier gas flow rate of 70 mL / min producing CNT with the highest yield, but this is not followed by best quality of CNT. CNT with best quality is obtained at a flow rate of argon carrier gas at 55 mL / min based on test results characterization by using SEM, EDX, Mapping, and RAMAN Spectroscopy. This research have not obtained CNT with aligned structured.

Abstrak :
Aligned Carbon Nanotube (ACNT) adalah salah satu jenis nanomaterial yang memiliki sifat luar biasa dan dapat digunakan untuk berbagai aplikasi di masa depan. LPG adalah salah satu sumber karbon yang dapat menghasilkan ACNT dengan metode Water Asssisted Chemical Vapour Deposition (WA-CVD). Penelitian ini mempelajari bagaimana kinerja dari substrat kuarsa dan bagaimana pengaruh suhu pertumbuhan dan waktu reaksi terhadap kualitas ACNT yang dihasilkan. Penelitian ini menghasilkan nanokarbon dengan yield yang cukup tinggi yaitu mencapai 2,70 mg/cm2. Hasil dari variasi waktu 100 menit dan 120 menit, didapatkan morfologi CNT yang dihasilkan pada waktu reaksi 100 menit lebih merata. Selanjutnya, uji pengaruh suhu terhadap hasil CNT menghasilkan produk pada suhu 800oC sebagai suhu optimum dimana yield dari nanokarbon adalah 2,22 mg/cm2 dan morfologi yang lebih merata dengan diameter 38 nm dilihat dari karakterisasi TEM, SEM-EDX, dan mapping. Sementara itu, keberadaan dari pengotor seperti karbon amorf dan CNT yang terenkapsulasi oleh katalis pada suhu 850oC didapatkan karena trade-off suhu tinggi dimana laju pelarutan karbon dalam katalis melebihi laju difusi dari karbon. Sedangkan sintesis dengan suhu 750oC hanya menghasilkan Carbon Nanofibers (CNF). Dengan hasil ini, dapat dikatakan bahwa orientasi dari CNT yang dihasilkan belum aligned atau dengan kata lain belum terbentuk ACNT. Meskipun demikian, orientasi dan morfologi paling merata didapatkan pada waktu reaksi 100 menit dengan 800oC. Perlakuan terhadap katalis menjadi suatu permasalahan belum didapatkannya ACNT. Selain itu, kinerja steam juga menjadi suatu masalah yang belum teratasi sehingga ACNT belum didapatkan. Waktu reaksi juga harus diturunkan untuk mendapatkan aligned dan penurunan waktu reaksi tidak akan jadi masalah untuk yield karena substrat kuarsa mampu menghasilkan yield yang tinggi. ......Aligned Carbon Nanotube (ACNT) is a nanomaterial with extraordinary properties and has very wide future applications. LPG is one of carbon source to produce ACNT through Water Assisted Chemical Vapour Deposition (WA-CVD) method. This research investigates performance of quartz substrate and effects of growth temperature and reaction time on the quality of ACNT. The synthesis in this research produced nanocarbon with high yield reaching 2.70 mg/cm2. At the varied reaction time (100 and 120 minutes), morphology of ACNT produced at 100 minutes is more uniform. Afterwards, growth temperature effect shows that 800oC is the optimum where the yield is reaching 2.22 mg/cm2 and more uniform morphology with diameter 38 nm characterized by TEM, SEM-EDX, and mapping. However, existence of polluter such as amorphous carbon and encapsulated CNT by the catalyst was obtained as trade-off of high temperature at 850oC where dissolution rate of carbon to catalyst is higher than diffusion rate of carbon. Meanwhile, at 750oC only Carbon Nanofiber (CNF) can be produced. Therefore, this research could not produced aligned structured of CNT. Yet, good orientation and morphology of CNT were produced at 100 minutes synthesis and at 800oC. Catalyst pretreatment is one of root cause of not producing ACNT. Besides that, the performance of steam could be another source of the problem. Reaction time has to be reduced until below 100 minutes to get aligned carbon nanotube. The reduced reaction time could still produced high yield since quartz substrate could bear high yield of nanocarbons including ACNT.

Abstrak :
Peningkatan jumlah penduduk menyebabkan berkurangnya Ruang Terbuka Hijau RTH karena lahan dialihfungsikan untuk memenuhi kebutuhan manusia, akibatnya terjadi peningkatan volume air limpasan yang menggenang. Genangan air limpasan ini mengandung polutan yang berbahaya sehingga memerlukan adanya pengelolaan. Tujuan dari penelitian ini adalah mengurangi konsentrasi polutan logam pada air limpasan dengan teknologi sistem bioretensi. Digunakan tiga reaktor yang diisi dengan komposisi media berupa pasir kuarsa 60, tanah 20, dan kompos 20. Ketiga reaktor ini mewakili variasi usia tanaman Reaktor I dan II, yaitu 4 dan 6 bulan serta variasi jenis tanaman Reaktor II dan III, yaitu 1 dan 2 jenis tanaman. Tanaman yang digunakan adalah Iris pseudacorus dan Chrysopogon zizanioides L. Roberty. Air limpasan sintetis yang digunakan berada pada rentang konsentrasi antara 0.04-0.11 ppm, baik untuk logam Pb maupun Zn. Pengaliran air limpasan sintetis dilakukan sebanyak 6 kali dengan debit sebesar 2.75 L/menit. Hasil menunjukkan bahwa kondisi optimal penurunan konsentrasi kedua jenis logam terjadi pada reaktor II berisi 2 jenis tanaman berusia 6 bulan, dengan efisiensi sebesar 83.3 untuk logam Pb dan 98.3 untuk logam Zn. Reaktor bioretensi dengan 2 jenis tanaman berusia 6 bulan lebih signifikan dalam mengurangi konsentrasi logam pada air limpasan.

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Population growth can reduce Green Open Space since the land is converted to fulfill human needs, as a results the volume of water runoff increased. This water contains harmful pollutants that need to manage. The purpose of this study is to reduce metal pollutants in water runoff by bioretention technology. Three reactors were filled with media composition in the form of quartz sand 60, soil 20, and compost 20. Those reactors represent the variation of plant age Reactor I and II, ie 4 and 6 months and variation of plant species Reactor II and III, ie 1 and 2 plant species. The plants species are Iris pseudacorus and Chrysopogon zizanioides L. Roberty. Concentration range of synthetic runoff water is between 0.04-0.11 ppm, both for Pb and Zn metals. Synthetic runoff drainage was conducted 6 times with discharge of 2.75 L min. The results showed that the optimum condition of concentration reduction for both metals occurred in reactor II 2 types of plants aged 6 months, with efficiency of 83.3 for Pb and 98.3 for Zn. Bioretention reactor with 2 types of plants aged 6 months is more significant in reducing metal concentration in runoff water.