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Journal : Sains dan Matematika

PEMURNIAN BATU KAPUR BERBASIS NANO KALSIT DENGAN METODE KOPRESIPITASI Putri, Nugrahani Primary; Kusumawati, Diah Hari
Sains & Matematika Vol 5, No 1 (2016): Oktober, Sains & Matematika
Publisher : Sains & Matematika

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Sintesis nano kalsit yang terbuat dari batu kapur menggunakan metode kopresipitasi berhasil diimplementasikan. Sintesis dilakukan dengan memvariasikan tekanan gas CO2 dan waktu pengendapan untuk mendapatkan kalsit dengan kemurnian tinggi dan ukuran partikel kecil. Data difraksi dikumpulkan menggunakan XRD, yang kemudian dianalisis menggunakan perangkat lunak Match dan Rietica untuk mendapatkan informasi tentang kecocokan, tingkat kemurnian, kepadatan, dan ukuran partikel. Dari analisis menggunakan Match, ditemukan bahwa batu kapur sebagai bahan dasar memiliki fase CaCO3 dan Ca(OH)2, sedangkan sampel yang disintesis dengan metode kopresipitasi memiliki fase kalsit. Hasil analisis berdasarkan Rietica menunjukkan bahwa hasil terbaik adalah sampel yang disintesis dengan variasi tekanan gas CO2 37,5 kgf/cm3 dan waktu pengendapan selama 36 jam.Synthesis nano calcite made of limestone using coprecipitation method has been succesfully implemented. Synthesis is held by varying the CO2 gas pressure and precipitation time in order to obtain calcite with high purity and small particle size. Diffraction data were collected using a XRD, which then analyzed using software Match and Rietica to obtain information about fitness, degree of purity, density and particle size. From analysis using Match, it was found that limestone as base material has CaCO3 and Ca(OH)2 phases, while samples which synthesized by coprecipitation method has calcite phase. Analysis result by Rietica shows that the best result is sample which synthesized with CO2 gas pressure variation of 37.5 kgf/cm3 and the settling time for 36 hours.
VARIASI MOLARITAS H2SO4 PADA POLIANILIN/H2SO4 Chomari, Moch. Nur; Kusumawati, Diah Hari
Sains & Matematika Vol 1, No 1 (2012): Oktober, Sains & Matematika
Publisher : Sains & Matematika

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Abstract

Synthetis of polyaniline has carried out using oxidation polymerization of aniline monomer to oxidant ammonium peroxydisulfat (NH)4S2O8 and H2SO4 as a source of proton doped. Variations in the molarity of H2SO4 conducted to determine of optimum polyaniline on electrical conductivity. Polyaniline samples were characterized by FTIR to determine the cluster function and the four-point probe method to determine the electrical conductivity. FTIR results showed that the samples were synthesized is polyaniline. Electrical conductivity test by used four point probe method showed higher acid molarity higher the electrical conductivity to the optimum. After reaching the optimum point, the electrical conductivity of polyaniline decreases followed by the molarity increases. Polyaniline has the most optimum conductivity of 1.833 S/cm when synthesized with 0.12 M H2SO4. 
KARAKTERISTIK TRANSMITANSI DAN ABSORBANSI KOMPOSIT EPOKSI/TIO2 SEBAGAI BAHAN ANTI ULTRAVIOLET Kusumawati, Diah Hari; Rachmawati, Dian Ayu
Sains & Matematika Vol 5, No 2 (2017): April, Sains & Matematika
Publisher : Sains & Matematika

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Nanopartikel TiO2 (titanium dioksida) telah banyak diteliti dan digunakan dalam aplikasi kehidupan sehari-hari, diantaranya sebagai bahan anti ultraviolet.  Karakteristik dari TiO2 selain mampu mentransmisikan Ultraviolet juga dapat mendegradasikan polutan organik menjadi air maupun karbondioksida. Namun titanium dioksida memerlukan material lain agar dapat diaplikasikan sebagai bahan anti UV, salah satunya adalah bahan perekat, dalam hal ini digunakan epoksi DGEBA.  Penelitian dilakukan dengan memvariasi titanium dioksida yang berfungsi sebagai filler pada komposit epoksi/TiO2 dan menganalisis pengaruhnya terhadap kemampuan transmitansi dan absorbansi gelombang ultraviolet.  Karakterisasi yang dilakukan adalah FTIR, UV-Vis dan pengukuran sudut kontak.  Hasil penelitian dengan variasi titanium dioksida 0,01-0,05 gram didalam epoksi diperoleh pola serapan Ti-O, Ti milik TiO2 dan O milik Epoksi DGEBA terletak pada 970,23 cm-1, transmitansi optimum sebesar 21% pada penambahan massa TiO2 sebanyak 0,03 gram. Hasil karakterisasi UV-Vis diperoleh absorbansi optimum pada 3,934, dan komposit termasuk dalam bahan hidrofilik dengan sudut kontak 30º-90º sehingga komposit epoksi/TiO2 bisa digunakan sebagai bahan anti debu (fogging) dan self cleaning.TiO2 nanoparticles (titanium dioxide) have been widely studied and used in everyday life applications, including as an anti-ultraviolet material. The characteristics of TiO2 besides being able to transmit Ultraviolet can also degrade organic pollutants into water and carbon dioxide. However, titanium dioxide requires other materials to be applied as an anti-UV material, one of which is an adhesive, in this case DGEBA epoxy is used. The study was carried out by varying titanium dioxide which functions as a filler in epoxy/TiO2 composites and analyzing its effect on the transmittance and absorbance ability of ultraviolet waves. Characterization performed was FTIR, UV-Vis and contact angle measurements. The results of research with variations of titanium dioxide 0.01-0.05 grams in the epoxy obtained the absorption pattern of Ti-O, Ti-owned TiO2 and O-owned Epoxy DGEBA located at 970.23 cm-1, the most optimum transmittance of 21% on the addition of TiO2 mass 0.03 gram. UV-Vis characterization results obtained optimum absorbance at 3,934, and composites included in hydrophilic material with a contact angle of 30º-90º so that the composite epoxy/TiO2 can be used as an anti-dust material (fogging) and self cleaning.
SIFAT MEKANIK BETON POLIMER EPOKSI DENGAN PENGISI PARTIKEL NANOKALSIT-SILIKA Putri, Nugrahani Primary; Kusumawati, Diah Hari; Rohmawati, Lydia
Sains & Matematika Vol 2, No 2 (2014): April, Sains & Matematika
Publisher : Sains & Matematika

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Polymer concrete environmentally friendly by utilizing the waste has been developed, one with waste mussel shells and sidoarjomud. Utilization of the waste is not optimal, for it to be used as filler in polymer concrete waste will be expected to have a highereconomic value. This research aimed to utilize the waste of cockle's shells and sidoarjo mud as filler of polymer concrete. Both waste firstsynthesized into nano particles by taking calcite and silica alone (mussel shells into nanocalsite and sidoarjo mud into nanosilica), beforebeing used as a filler. Once formed nanocalsite and nanosilica, composites with epoxy resin matrix and filler nanocalsite and nanosilicacreated by varying the percentage weight of each filler 5-10% by weight. Then the characterization was conducted in the form of tensiletest, hardness, bending and impact test. The test results showed that the resulting polymer concrete has physical properties, mechanical,thermal and microscopic good and has an optimum value at 10% filler calcite + 10% silica, which is 218.39 MPa compressive strength,tensile strength of 3.32 MPa, a strong fracture of 8.04 MPa and hardness values ranged from 16.08 to 18.3 HVN. Overall the resultshave met the standards for the characterization of polymer concrete.
KARAKTERISASI SIFAT LISTRIK DAN MAGNETIK PANI/HCL/FE3O4 AKIBAT PENAMBAHAN FE3O4 PADA KOMPOSIT PANI/HCL Purwanto, Purwanto; Kusumawati, Diah Hari
Sains & Matematika Vol 2, No 1 (2013): Oktober, Sains & Matematika
Publisher : Sains & Matematika

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Abstract

Fabrication PANi/HCl has been carried out by interfacial polymerization method, Fe3O4 nanoparticles by coprecipitation method and composite with compacting method. In the manufacture of composites, the addition of Fe3O4 nanoparticles aims to improve the electrical properties and characteristics of the magnetic properties of the composite PANi/HCl/Fe3O4. Characterization was conducted on the electrical conductivity measurements, characterization of XRD and VSM. Characterization results in this study could be seen that with the addition of Fe3O4 in PANi/HCl/Fe3O4 the electrical conductivity decreases significantly with increasing addition of Fe3O4. The maximum electrical conductivity of PANi/HCl at 16,667 S/cm decreased with the highest reduction at 40% Fe3O4 with a value of 21.1 × 10-4 S/cm. With the addition of Fe3O4 nanoparticles of the magnetic properties PANi/HCl in PANi/HCl/Fe3O4 composites increased significantly with increasing addition of Fe3O4 nanoparticles. The enhancement magnetic properties was shown by the increasing value of saturation magnetization (Ms) PANi/HCl in the composite PANi/HCl/Fe3O4. For the PANi/HCl with a value of Ms = 25.48 × 10-4 emu/cm3 experienced the highest increase in the addition of 40% Fe3O4, that is the value of Ms = 18.5 emu/cm3.
Pemurnian Batu Kapur Berbasis Nano Kalsit dengan Metode Kopresipitasi Putri, Nugrahani Primary; Kusumawati, Diah Hari
Sains & Matematika Vol 5, No 1 (2016): Oktober, Sains & Matematika
Publisher : Sains & Matematika

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Abstract

Sintesis nano kalsit yang terbuat dari batu kapur menggunakan metode kopresipitasi berhasil diimplementasikan. Sintesis dilakukan dengan memvariasikan tekanan gas CO2 dan waktu pengendapan untuk mendapatkan kalsit dengan kemurnian tinggi dan ukuran partikel kecil. Data difraksi dikumpulkan menggunakan XRD, yang kemudian dianalisis menggunakan perangkat lunak Match dan Rietica untuk mendapatkan informasi tentang kecocokan, tingkat kemurnian, kepadatan, dan ukuran partikel. Dari analisis menggunakan Match, ditemukan bahwa batu kapur sebagai bahan dasar memiliki fase CaCO3 dan Ca(OH)2, sedangkan sampel yang disintesis dengan metode kopresipitasi memiliki fase kalsit. Hasil analisis berdasarkan Rietica menunjukkan bahwa hasil terbaik adalah sampel yang disintesis dengan variasi tekanan gas CO2 37,5 kgf/cm3 dan waktu pengendapan selama 36 jam.Synthesis nano calcite made of limestone using coprecipitation method has been succesfully implemented. Synthesis is held by varying the CO2 gas pressure and precipitation time in order to obtain calcite with high purity and small particle size. Diffraction data were collected using a XRD, which then analyzed using software Match and Rietica to obtain information about fitness, degree of purity, density and particle size. From analysis using Match, it was found that limestone as base material has CaCO3 and Ca(OH)2 phases, while samples which synthesized by coprecipitation method has calcite phase. Analysis result by Rietica shows that the best result is sample which synthesized with CO2 gas pressure variation of 37.5 kgf/cm3 and the settling time for 36 hours.
Karakterisasi Sifat Listrik dan Magnetik PANI/HCl/Fe3O4 akibat Penambahan Fe3O4 pada Komposit PANI/HCl Purwanto, Purwanto; Kusumawati, Diah Hari
Sains & Matematika Vol 2, No 1 (2013): Oktober, Sains & Matematika
Publisher : Sains & Matematika

Show Abstract | Download Original | Original Source | Check in Google Scholar

Abstract

Fabrication PANi/HCl has been carried out by interfacial polymerization method, Fe3O4 nanoparticles by coprecipitation method and composite with compacting method. In the manufacture of composites, the addition of Fe3O4 nanoparticles aims to improve the electrical properties and characteristics of the magnetic properties of the composite PANi/HCl/Fe3O4. Characterization was conducted on the electrical conductivity measurements, characterization of XRD and VSM. Characterization results in this study could be seen that with the addition of Fe3O4 in PANi/HCl/Fe3O4 the electrical conductivity decreases significantly with increasing addition of Fe3O4. The maximum electrical conductivity of PANi/HCl at 16,667 S/cm decreased with the highest reduction at 40% Fe3O4 with a value of 21.1 × 10-4 S/cm. With the addition of Fe3O4 nanoparticles of the magnetic properties PANi/HCl in PANi/HCl/Fe3O4 composites increased significantly with increasing addition of Fe3O4 nanoparticles. The enhancement magnetic properties was shown by the increasing value of saturation magnetization (Ms) PANi/HCl in the composite PANi/HCl/Fe3O4. For the PANi/HCl with a value of Ms = 25.48 × 10-4 emu/cm3 experienced the highest increase in the addition of 40% Fe3O4, that is the value of Ms = 18.5 emu/cm3.
Karakteristik Porositas dan Antibakteri Wound Dressing Nanofiber PVA-Pare (Momordica charantia) Fadhlurrahman Nur, Ahmad Faruq; Kusumawati, Diah Hari
Sains dan Matematika Vol. 8 No. 2 (2023): Oktober, Sains & Matematika
Publisher : Universitas Negeri Surabaya

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.26740/sainsmat.v8n2.p32-40

Abstract

Ekstrak buah pare (Momordica charantia) dikenal memiliki beragam manfaat dalam bidang medis dengan sifat penyembuhan yang sangat baik. Sifat penyembuhan pada Momordica charantia dipengaruhi oleh adanya kandungan bioaktif seperti; asam fenolik, flavonoid, karotenoid, triterpenoid, dan fitosterol, yang juga dapat menghambat pertumbuhan beberapa bakteri seperti B. subtilis dan E. coli yang banyak ditemukan pada luka. Tujuan penelitian ini adalah untuk menganalisis karakteristik porositas dan efektivitas sifat antibakteri pada nanofiber PVA-Momordica charantia terhadap bakteri B. subtilis dan E. coli. Proses fabrikasi nanofiber PVA-Momordica charantia dilakukan dengan metode electrospinning. Adapun jenis uji yang dilakukan pada nanofiber PVA-Momordica charantia adalah FTIR, SEM, dan antibakteri. Hasil penelitian menunjukkan bahwa nanofiber PVA-Momordica charantia memiliki gugus fungsi C=O dan CH2 yang menunjukkan adanya kandungan Momordica charantia dan PVA, memiliki ukuran diameter pori dengan rentang 1.310-860 nm, memiliki ukuran diameter fiber dengan rentang 147-185 nm dan porositas antara 53-60%. Nanofiber PVA-Momordica charantia dengan konsentrasi Momordica charantia 25% merupakan komposisi nanofiber yang paling optimum untuk aplikasi wound dressing, konsentrasi tersebut memiliki aktivitas antibakteri yang sangat baik terutama pada bakteri gram positif dengan efektivitas sebesar 90% (B. Subtilis) serta pada gram negatif dengan efektivitas 58% (E. coli).      
Karakteristik Antibakteri dari Wound Dressing PVA – Sodium Alginat Putri Ramadhani, Novtantian Erlinda; Kusumawati, Diah Hari
Sains dan Matematika Vol. 8 No. 2 (2023): Oktober, Sains & Matematika
Publisher : Universitas Negeri Surabaya

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.26740/sainsmat.v8n2.p41-49

Abstract

Sodium Alginat merupakan polimer bahan alam yang berkembang dalam bidang kesehatan dengan sifat biokompatibel, biodegradasi, dan sifat antibakteri yang baik. Tujuan penelitian ini adalah menganalisis karakteristik wound dressing dari PVA-Sodium Alginat dan menganalisis efektivitas antibakteri dari wound dressing PVA-Sodium Alginat. Sintesis nanofiber dilakukan menggunakan metode electrospinning dengan parameter yang digunakan yaitu laju alir 1 ml/jam, jarak jarum antar kolektor sejauh 13 cm, serta tegangan sebesar 15 kV. Nanofiber yang dihasilkan kemudian dikarakterisasi menggunakan FTIR, SEM, uji antibakteri, dan uji tarik. Hasil FTIR nanofiber PVA-Sodium Alginat diperoleh gugus fungsi C-H yang menunjukkan adanya PVA , serta COO asimetris dan simetris dari kandungan Sodium Alginat. Karakterisasi SEM menunjukkan morfologi berbentuk serat dengan ukuran diameter pada rentang 99 – 142 nm, porositas 43% - 47%, dan ukuran pori 0,915 m – 1,121 m . Hasil karakterisasi SEM meliputi struktur morfologi, ukuran diameter, porositas dan ukuran pori nanofiber PVA-Sodium Alginat yang memenuhi karakteristik sebagai wound dressing yaitu pada variasi Sodium Alginat 3%. Hasil uji tarik nanofiber PVA-Sodium Alginat didapatkan nilai kuat tarik 3,26 MPa, regangan sebesar 6%, dan modulus elastisitas sebesar 0,54 MPa. Nanofiber PVA-Sodium Alginat memiliki aktivitas antibakteri yang sangat baik pada bakteri gram negatif (Eschericia coli) dengan efektivitas antibakteri sebesar 97,5%, namun tidak dapat menghambat pertumbuhan untuk bakteri gram positif (Staphylococcus aureus).