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Pengaruh pH NH4OH pada Sintesis Mangan Ferrite (MnFe2O4) Berbasis Pasir Besi Alam dengan Metode Kopresipitasi sebagai Adsorben Ion Logam Berat
No full textMnFe2O4 has been synthesized by coprecipitation method with variation of pH NH4OH 11,7; 12,0; dan 12,7. The process of preparation started from mixing of Iron Sand and Mangan Clorida powder with HCl as solvent and NH4OH as setting solution. Sampels were dried and characterization include analyze morphology (SEM), powder density, crystal size and structure (XRD), magnetic properties (VSM) and absorption of heavy metal waste (Pb and Cu) (AAS). The result of SEM showed that MnFe2O4 has been able to aglomeration. The results of XRD showed the higher the pH is given the smaller the crystallite grain size so that the powder more tight. The result of VSM showed that the optimum coercivity was achieved when pH of NH4OH 12,7 with a value of 43,82 Oe, magnetic saturation 62.78 emu/g, remanence 1.96 emu/g. AAS characterization showed that nanoparticles MnFe2O4 were able to absorb heavy metal Pb is bigger than Cu.Telah dilakukan sintesis MnFe2O4 dengan variasi pH NH4OH 11,7; 12,0; dan 12,7 dengan metode kopresipitasi. Proses preparasi dimulai dari pencampuran serbuk Pasir Besi dan Mangan Clorida dengan pelarut HCl dan larutan pengendap NH4OH. Sampel kemudian dikeringkan dan dikarakterisasi, meliputi analisa morfologi (SEM), kerapatan serbuk (Densitas serbuk), ukuran dan struktur kristal (XRD), sifat magnetik (VSM) dan penyerapan limbah logam berat Pb dan Cu (AAS). Hasil SEM menunjukkan bahwa sampel MnFe2O4 mengalami aglomerasi (penggumpalan). Dari hasil uji XRD, bahwa semakin tinggi pH yang diberikan maka ukuran butir kristal semakin kecil sehingga serbuk semakin rapat. Hasil VSM menunjukkan koersivitas optimum terdapat pada saat pH NH4OH 12,7 dengan nilai koersivitas 43,82 Oe, saturasi magnetik 62,78 emu/g, saturasi remanensi 1,96 emu/g. Hasil penyerapan AAS menunjukkan bahwa nanopartikel MnFe2O4 mampu menyerap limbah logam berat Pb lebih besar dibandingkan dengan Cu.Skripsi Sarjan
Sintesis Mg1-xNixFe2O4 Berbasis Pasir Besi Alam Sebagai Adsorben Ion Logam Berat
No full textNanoparticle Magnesium Nickel Ferrite (Mg1-xNixFe2O4) has been synthesized by
using co-presipitation method. Manufacturing of Mg1-xNixFe2O4 are done by
varying composition MgCl2.6H2O and NiCl2.6H2O synthesis as x of Mg1-xNixFe2O4
x =(0,25 ;0,50 and 0,75) . To inform characteristic material from Mg1-xNixFe2O4 ,
Sample was characterized by SEM (Scanning Electron Microscopy), XRD (X-ray
Diffraction), VSM (Vibrating Sample Magnetometer), dan AAS (Atomic Adsorption
Spectroscopy). Based on analysis using SEM seen morphology of Mg1-xNixFe2O4.
From diffraction patterns from analize XRD seen that Mg1-xNixFe2O4 is single phase
Magnesium Nickel Ferrite, cubic crystal structure, and the grain parameters is
decreasing with increasing of composition Ni2+ is 8,395 – 8,377 Å and particle size
is 14,9 nm. The result of Vibrating Sample Magnetometer (VSM) shows that Mg1-
xNixFe2O4 is superparamagnetic. In addition, atomic adsorption spectroscopy (AAS)
was also tested to determine the adsorption ability of heavy metal ion (Pb) and (Cu)
by Mg1-xNixFe2O4 as adsorbent. Based on the result shows that when composition
Ni2+ Mg1-xNixFe2O4 is increasing and adsorption capacity is decreasing. So, the
largest adsorption capacity x=0,25 is Mg1-xNixFe2O4 on is 190,5 mg/g.Telah berhasil dilakukan sintesis nanoparikel Magnesium Nickel Ferrite (Mg1-
xNixFe2O4) dengan menggunakan metode kopresipitasi. Pembuatan nanopartikel ini
dilakukan dengan memvariasikan komposisi MgCl2.6H2O dan NiCl2.6H2O sebagai
penyusun yang dinyatakan dalam nilai x pada Mg1-xNixFe2O4 yaitu x= (0,25; 0,50
dan 0,75). Untuk mengetahui sifat-sifat bahan dari sampel Mg1-xNixFe2O4 maka
dilakukan karakterisasi sampel SEM (Scanning Electron Microscopy), XRD (X-ray
Diffraction), VSM (Vibrating Sample Magnetometer), dan AAS (Atomic Adsorption
Spectroscopy). Pada hasil SEM memberikan informasi tentang morfologi Mg1-
xNixFe2O4. Dari pola difraksi yang dihasilkan dari analisa menggunakan XRD
terlihat bahwa nanopartikel Mg1-xNixFe2O4 membentuk fase tunggal yaitu
Magnesium Nickel Ferrite, struktur kristal kubik, dan parameter kisi yang semakin
menurun seiring meningkatnya konsentrasi Ni2+ yaitu 8,395 – 8,377 Å, serta ukuran
partikel yang terbaik terdapat pada sampel x=0,50 yaitu 14,9 nm. Pada pengukuran
magnetik oleh Vibrating Sample Magnetometer (VSM) mengungkapkan bahwa
sampel tersebut adalah superparamagnetics. Pada pengukuran adsorpsi dengan
Atomic Adsorption Spectroscopy (AAS) didapat hasil bahwa semakin kecil
komposisi Ni2+ semakin besar pula kapasitas adsorpsinya terhadap ion logam berat
Pb dan Cu, yaitu pada sampel x=0,25memiliki kapasitas adsorpsi adalah 190,5 mg/g.Kertas Karya Diplom
Pengaruh pH NH4OH pada Sintesis Mangan Ferrite (MnFe2O4) Berbasis Pasir Besi Alam dengan Metode Kopresipitasi sebagai Adsorben Ion Logam Berat
No full textMnFe2O4 has been synthesized by coprecipitation method with variation of pH NH4OH 11,7; 12,0; dan 12,7. The process of preparation started from mixing of Iron Sand and Mangan Clorida powder with HCl as solvent and NH4OH as setting solution. Sampels were dried and characterization include analyze morphology (SEM), powder density, crystal size and structure (XRD), magnetic properties (VSM) and absorption of heavy metal waste (Pb and Cu) (AAS). The result of SEM showed that MnFe2O4 has been able to aglomeration. The results of XRD showed the higher the pH is given the smaller the crystallite grain size so that the powder more tight. The result of VSM showed that the optimum coercivity was achieved when pH of NH4OH 12,7 with a value of 43,82 Oe, magnetic saturation 62.78 emu/g, remanence 1.96 emu/g. AAS characterization showed that nanoparticles MnFe2O4 were able to absorb heavy metal Pb is bigger than Cu.Telah dilakukan sintesis MnFe2O4 dengan variasi pH NH4OH 11,7; 12,0; dan 12,7 dengan metode kopresipitasi. Proses preparasi dimulai dari pencampuran serbuk Pasir Besi dan Mangan Clorida dengan pelarut HCl dan larutan pengendap NH4OH. Sampel kemudian dikeringkan dan dikarakterisasi, meliputi analisa morfologi (SEM), kerapatan serbuk (Densitas serbuk), ukuran dan struktur kristal (XRD), sifat magnetik (VSM) dan penyerapan limbah logam berat Pb dan Cu (AAS). Hasil SEM menunjukkan bahwa sampel MnFe2O4 mengalami aglomerasi (penggumpalan). Dari hasil uji XRD, bahwa semakin tinggi pH yang diberikan maka ukuran butir kristal semakin kecil sehingga serbuk semakin rapat. Hasil VSM menunjukkan koersivitas optimum terdapat pada saat pH NH4OH 12,7 dengan nilai koersivitas 43,82 Oe, saturasi magnetik 62,78 emu/g, saturasi remanensi 1,96 emu/g. Hasil penyerapan AAS menunjukkan bahwa nanopartikel MnFe2O4 mampu menyerap limbah logam berat Pb lebih besar dibandingkan dengan Cu.Skripsi Sarjan
Sintesis Mg1-xNixFe2O4 Berbasis Pasir Besi Alam Sebagai Adsorben Ion Logam Berat
No full textNanoparticle Magnesium Nickel Ferrite (Mg1-xNixFe2O4) has been synthesized by
using co-presipitation method. Manufacturing of Mg1-xNixFe2O4 are done by
varying composition MgCl2.6H2O and NiCl2.6H2O synthesis as x of Mg1-xNixFe2O4
x =(0,25 ;0,50 and 0,75) . To inform characteristic material from Mg1-xNixFe2O4 ,
Sample was characterized by SEM (Scanning Electron Microscopy), XRD (X-ray
Diffraction), VSM (Vibrating Sample Magnetometer), dan AAS (Atomic Adsorption
Spectroscopy). Based on analysis using SEM seen morphology of Mg1-xNixFe2O4.
From diffraction patterns from analize XRD seen that Mg1-xNixFe2O4 is single phase
Magnesium Nickel Ferrite, cubic crystal structure, and the grain parameters is
decreasing with increasing of composition Ni2+ is 8,395 – 8,377 Å and particle size
is 14,9 nm. The result of Vibrating Sample Magnetometer (VSM) shows that Mg1-
xNixFe2O4 is superparamagnetic. In addition, atomic adsorption spectroscopy (AAS)
was also tested to determine the adsorption ability of heavy metal ion (Pb) and (Cu)
by Mg1-xNixFe2O4 as adsorbent. Based on the result shows that when composition
Ni2+ Mg1-xNixFe2O4 is increasing and adsorption capacity is decreasing. So, the
largest adsorption capacity x=0,25 is Mg1-xNixFe2O4 on is 190,5 mg/g.Telah berhasil dilakukan sintesis nanoparikel Magnesium Nickel Ferrite (Mg1-
xNixFe2O4) dengan menggunakan metode kopresipitasi. Pembuatan nanopartikel ini
dilakukan dengan memvariasikan komposisi MgCl2.6H2O dan NiCl2.6H2O sebagai
penyusun yang dinyatakan dalam nilai x pada Mg1-xNixFe2O4 yaitu x= (0,25; 0,50
dan 0,75). Untuk mengetahui sifat-sifat bahan dari sampel Mg1-xNixFe2O4 maka
dilakukan karakterisasi sampel SEM (Scanning Electron Microscopy), XRD (X-ray
Diffraction), VSM (Vibrating Sample Magnetometer), dan AAS (Atomic Adsorption
Spectroscopy). Pada hasil SEM memberikan informasi tentang morfologi Mg1-
xNixFe2O4. Dari pola difraksi yang dihasilkan dari analisa menggunakan XRD
terlihat bahwa nanopartikel Mg1-xNixFe2O4 membentuk fase tunggal yaitu
Magnesium Nickel Ferrite, struktur kristal kubik, dan parameter kisi yang semakin
menurun seiring meningkatnya konsentrasi Ni2+ yaitu 8,395 – 8,377 Å, serta ukuran
partikel yang terbaik terdapat pada sampel x=0,50 yaitu 14,9 nm. Pada pengukuran
magnetik oleh Vibrating Sample Magnetometer (VSM) mengungkapkan bahwa
sampel tersebut adalah superparamagnetics. Pada pengukuran adsorpsi dengan
Atomic Adsorption Spectroscopy (AAS) didapat hasil bahwa semakin kecil
komposisi Ni2+ semakin besar pula kapasitas adsorpsinya terhadap ion logam berat
Pb dan Cu, yaitu pada sampel x=0,25memiliki kapasitas adsorpsi adalah 190,5 mg/g.Kertas Karya Diplom
Pengaruh Variasi Suhu Sintering terhadap Karakteristik Keramik Berbasis Al2O3, Glass Beaddan Bentonit
No full textThe production of ceramics based on bentonite and glass beads and the addition of Al2O3 of 30 (wt%) with sinter temperature variation 900oC, 1000oC, 1100oC and 1200oC. Preparation process of raw materials ranging from mixing bantonite powder 35 wt%, glass bead 35 wt% t and alumina 30 wt%, then printed with style 8 ton to form pellet with diameter 18,5 and thickness 4,3 mm. The samples were then dried using an oven at 100 ° C for 24 hours. Characterization tested includes physical properties (density, porosity, water absorption and hardness), microstructure using Optical Microscope and phase analysis using XRD (X-Ray Diffraction). From the measurement of bulk density and hardness on ceramics based on bentonite and glass bead and alumina with temperature variation shows that bulk density and hardness value tends to increase while porosity and water absorption tends to decrease. The optimum condition is reached at 1100oC temperature yielding bulk density = 2,43 g / cm3, porosity = 1.91%, water absorption = 0,8% and hardness = 878,29 kgf / mm2..The effect of sinter temperature variation on bentonite based ceramic And glass beads and alumina tend to increase the density and hardness value but decrease the porosity and wter absorption. The phase formed is the major phase anorthite (Al2CaSi2O8) and microline minor phase (KAlSi3O8)Telah dilakukan pembuatan keramik berbasis bentonit dan glass bead dan penambahan Al2O3 sebanyank 30 (wt%) dengan variasi suhu sinter 900oC, 1000oC, 1100oC dan 1200oC. Proses preparasi bahan baku mulai dari pencampuranserbuk bantonite 35 wt%, glass bead 35 wt%t dan alumina 30 wt%,lalu dicetak dengan gaya 8 tonf sehingga membentuk pellet dengan diameter 18,5 dan tebal 4,3 mm. Sampel yang telah dicetak kemudian dikeringkan menggunakan oven dengan temperatur 100°C selama 24 jam. Karakterisasi yang diuji meliputi sifat fisis (densitas, porositas, water absorption dan kekerasan), mikrostruktur menggunakan Optical Microscope dan analisis fasa menggunakan XRD (X-Ray Diffraction). Dari hasil pengukuran bulk density dan kekerasan pada keramik berbasis bentonit dan glass bead dan alumina dengan variasi suhu menunjukkan bahwa nilai bulk density dan kekerasan cenderung meningkat sedangkan porositas dan water absorption cenderung menurun. Kondisi optimum dicapai pada suhu 1100oC menghasilkan bulk density = 2,43 g/cm3, porosity =1,91 %, water absorption = 0,8 % dan kekerasan = 878,29 kgf/mm2..Pengaruh variasi suhu sinter terhadap keramik berbasis bentonit dan glass bead dan alumina cenderung meningkatkan nilai densitas dan kekerasannya namun menurunkan porosity dan wter absorptinnya. Fasa yang terbentuk adalah fasa mayor anorthite (Al2CaSi2O8) dan fasa minor microline (KAlSi3O8).Skripsi Sarjan
Pengaruh Komposisi MgO Terhadap Karakterisasi Keramik Berbasis Bentonit dan Glass Bead
No full textCeramics have been made from the main material of bentonite and glassbead
(SiO2) with the addition of Magnesium Oxide (MgO) with variation of
composition 0, 10, 20 and 30 (wt%) using powder metallurgy method. Bentonite-
Glassbead and Magnesium Oxide powder in mixing using HEM for 120 minutes
(wet milling). The sample was compressed with a pressure of 7,845 MPa using a
hydraulic press (die pressing). The samples were sintered using a High
Temperature Furnace at 900 ° C with a holding time of 4 hours. Samples were
characterized by physical properties (bulk density, True Density, Particle
diameter, porosity, water Absorbtions), microstructure analysis of samples using
XRD, hardness test using Micro Hardness Tester, pore diameter with OM. It was
found that in the addition of MgO 0, 10, 20 and 30 (wt%) with sintering
temperature 900oC (4 hours) have physical properties, bulk Density 2,3 g/cm2
(SP-1) -2,72 g/cm2 (SP-4 ), true Density 2,16 g/cm2 (SP-1)-2,3 g/cm2 (SP-4),
mean particle diameter 5,86 μm (SP-1)- 5,21 μm (SP-4), porosity 32,57% (SP-2)-
29,19% (SP-4), water absosrtions 20,24% (SP-2)-15,09%(SP-4), pore diameter
(25,75 (1) - (13,03 (4))%, hardness 4851,87 N/mm2 (SP-1)- 3735,76 N/mm2(SP-4)
while the phase formed at 0% (nepheline, anorthite) and 30 % (Clinoenstatite and
forstatite).Telah dilakukan pembuatan keramik dari bahan utama bentonit dan glass bead
(SiO2) dengan penambahan Magnesium Oksida (MgO) dengan variasi komposisi
0 , 10 ,20 dan 30 (wt%) menggunakan metode metalurgi serbuk. Serbuk Bentonit-
Glassbead dan Magnesiom Oksida dimixing menggunakan HEM selama 120
menit (wet milling). Sampel dicetak dengan tekanan 7,845 MPa menggunakan
hydraulic press(die pressing). Sampel disinter menggunakan High Temperature
Furnace pada suhu 900oC dengan waktu penahanan selama 4 jam. Sampel
dikarakterisasi sifat fisis (bulk density, True Density ,Diameter partikel, porositas ,
water Absorbtions), analisis mikrostruktur sampel menggunakan XRD, uji
kekerasan dengan menggunakan Micro Hardness Tester, diameter pori dengan
OM. Didapatkan bahwa pada penambahan MgO 0 ,10 ,20 dan 30(wt%) dengan
suhu sintering 900oC (4 jam) memiliki sifat fisis,bulk Density 2,3 g/cm2 (SP-1) -
2,72 g/cm2 (SP-4 ), true Density 2,16 g/cm2 (SP-1)-2,3 g/cm2 (SP-4), mean
diameter partikel 5,86 μm (SP-1)- 5,21 μm (SP-4), porositas 32,57% (SP-2)-
29,19% (SP-4), water Absosrtions 20,24% (SP-2)-15,09%(SP-4), diameter pori
25,75μm(SP-1)-13,03 μm (SP-4), Kekerasan 4851,87 N/mm2 (SP-1)- 3735,76
N/mm2(SP-4) sedangkan fasa yang terbentuk pada 0%(nepheline, anorthite) dan
30% (clinoenstatite ,Nepheline dan forsterite).
Kata Kunci: Bentonit,glass bead,MgO, metalurgi serbuk, sinteringSkripsi Sarjan
Pengaruh Variasi Komposisi Al2O3 terhadap Sifat Fisis, Mekanis, Struktur Mikro, dan Fasa dalam Pembuatan Keramik Berbasis Bentonit dan Glass Bead.
No full textHas been made the manufacture of ceramics based on bentonite and glass bead with
various of composition Al2O3 in wt%. The process of preparation material by using
powder metallurgy method with composition of bentonite : glass bead : Al2O3 are
50:50:0 ; 45:45:10 ; 40:40:20 ; 35:35:30 wt% and then the powder mixture was wet
milling with toluene media using HEM for 2 hours. Then powder sample was dried
in the oven at 100oC for 24 hours and characterized including true density and
Particle Size Analyzer (PSA). Next powder sample was compressed with pressure 80
kgf/cm2 in room temperature into a pellet with diameter 16 mm, thickness 6 mm, and
mass 2,5 grams. Then pellet sample was sintered only at 900oC with 4 hours
detention and characterized including : Physical properties testing is bulk density,
porosity, and water absorption by using Archimedes principle. Testing mechanical
properties namely hardness by using Hardness Vickers (HV) method. Analysis of
microstructure and phase used Optical Microscope (OM) and X-Ray Diffraction. The
test result showed value of true density, bulk density, and hardness tends to increase
while the porosity value and water absorption tends to decrease with the addition of
Al2O3 more a lot. The optimum condition was obtained in addition of 30 wt% of
Al2O3 which resulted the value of true density 2,32 g/cm3, bulk density 2,39 gr/cm³,
porosity 5,57 %, water absorption 2,46 %, hardness 631,76 kgf/mm², and averages
size of particle diameter 4,27 μm. The result of analysis by using XRD there are 2
phases which formed namely major anorthite (Al2CaSi2O8) phase and microline
minor phase (KalSi3O8).96 HalamanSkripsi Sarjan
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Get PDF“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
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