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"Telah dilakukan pengukuran keluaran pesawat teleterapi 60Co dalam medium akrilik dan air. Pengukuran bertujuan untuk memperoleh informasi mengenai nilai persentasi dosis kedalaman (PDD) dan bacaan relatif berkas radiasi gamma 60Co dalam medium akrilik dan air. Pengukuran dilakukan menggunakan bilik ionisasi plan parallel Markus 23343 dan Farmer PTW 30013 dengan teknik SSD 80 cm dan variasi luas lapangan penyinaran 4 x 4 cm2 sampai dengan 30 x 30 cm2.Hasil pengukuran PDD medium akrilik dan air tidak jauh berbeda, yaitu kurang dari 1.2 %. Nilai bacaan relatif lapangan radiasi dari 6 x 6 cm2 sampai dengan 30 x 30 cm2 dalam medium akrilik tidak berbeda jauh dengan pengukuran dalam medium air yaitu kurang dari 2 %. Ini menunjukkan bahwa fantom akrilik dapat menggantikan fantom air dalam dosimetri berkas gamma pada kondisi tertentu.

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Measurement of 60Co output has been performed in acrylic (PMMA) and water media using Markus ionization chamber 23343 and Farmer PTW 30013 with SSD 80 cm and field sizes variation from 4 x 4 cm2 until 30 x 30 cm2. The purpose is to get comparative information on Percentage Depth Dose (PDD) and relative reading of gamma ray radiation in acrylic and water media.Results showed PDD in acrylic to be approximative to that in water medium, not more than 1.2 % difference. Relative reading for field sizes from 6 x 6 cm2 until 30 x 30 cm2 in acrylic medium is also close to that in water, not more than 2 % difference. This showed that acrylic phantom may be used as a substitute of water phantom in a certain condition."

"PMMA is one of the main raw materials for the injection molding process in the lens industries. Since this process requires extremely careful techniques to obtain lens with the best quality, it leads to a high rate of product rejection. These rejected products do not only pose an issue for the industrial environment and require storage space,their price also falls significantly. Among the solutions to this problem is to reuse the rejected products as substitute materials for the manufacture of another product?s part such as lamp holders. This process reuses rejected PMMAcontaining products in the ABS base polymer industries so as to generate PMMA-containing products with better physical properties. In this experiment, 10 to 40 % (w/w) of rejected PMMA was blended with ABS resins. Themonomer content in the ABS resins was analyzed by NMR. Moreover, the mechanical, thermal, and morphological properties of the blended products were also examined. The NMR analysis showed that the resin contained 21.6 % butadiene monomer, in which its value was higher than the value required for materials with high-impact classapplication. The blend of resins and rejected PMMA (10-30% w/w) could increase the tensile strength value and decrease Izod impact strength and elongation percentage. The morphological analysis showed that this increased PMMA content may also result in widespread brittle areas. Since the blend was designed without compatibilizers,the DSC analysis indicated that the resulting blend in any ratios was not completely miscible. It was revealed that ABS resins containing 10% PMMA was the best blend for the polymer engineering application and this blend still had adequate properties and elastomer content required."

"Sebuah penelitian sistematis telah dilakukan untuk mengetahui penyebab utama rendahnya tingkat kristalinitas nanopartikel titania (TiO2) di dalam nanokomposit TiO2-PMMA hasil proses sol-gel. Dari hasil investigasi diketahui bahwa fasa TiO2 amorfus di dalam nanokomposit disebabkan oleh pembentukan cepat dari jaringan kaku Ti-OH selama tahapan hidrolisis dan kondensasi."

"ABSTRAKNPS belakangan mulai banyak muncul di pasar gelap narkoba di berbagai negara di dunia termasuk Indonesia. NPS umumnya disintesis dengan memanipulasi struktur kimia dari suatu senyawa psikoaktif sehingga menghasilkan produk dengan struktur yang serupa namun tidak identik dengan senyawa psikoaktif ilegal. Pada tahun 2016, para-metoksimetamfetamina PMMA , metamfetamina dengan substituen metoksi merupakan NPS yang paling banyak ditemui pada sampel yang dikirim ke Balai Laboratorium Narkoba BNN oleh penyidik. Keterbatasan bahan pembanding PMMA menjadi hambatan dalam mengidentifikasi sampel narkotika. Tujuan dari penelitian ini adalah untuk mensintesis PMMA dari metamfetamina sabu melalui 4 tahap reaksi : nitrasi, reduksi, hidrolisis garam diazonium, dan metilasi. Identifikasi dan karakterisasi senyawa menggunakan KLT, UV, dan GC-MS. Purifikasi senyawa PMMA menggunakan KLT preparatif Silica Gel RP18 F254S dengan komposisi eluen etil asetat: metanol: ammonia 85: 10: 5 yang ditunjukkan dengan bercak pada Rf 0.3. PMMA hasil sintesis dengan kemurnian 99,3790 telah digunakan sebagai bahan pembanding untuk analisis sampel. Tablet mengandung PMMA dan sampel spike dianalisis menggunakan metode GC-MS dengan kolom kapiler HP-5MS 30 m x 0.25 mm i.d dan waktu analisis kurang dari 30 menit. Kromatogram menunjukkan puncak pada 8,504 menit dengan pola fragmentasi 58, 91, 121, 149 and 179 m/z.

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ABSTRACTRecently, New Psychoactive Substances NPS have rapidly emerged on the illicit drug market in many countries around the world including Indonesia. NPS commonly are created by manipulating chemical structures of other psychoactive drugs so that the resulting products are structurally similar but not identical to illegal psychoactive. In 2016, Para methoxymethamphetamine PMMA , a methoxy substituted methamphetamine was the most common NPS sample submitted to Drug Testing Laboratory National Narcotics Board of Indonesia by investigators. Lack of reference standard of PMMA became an obstacle to identify this compound in narcotic samples. The aim of this study was to synthesize PMMA from methamphetamine sabu through 4 stages of reactions nitration, reduction, hydrolysis of diazonium salts, and methylation. Identification and characterization of the compounds were performed by employing TLC, UV, and GC MS. Purification of PMMA was carried out using preparative TLC Silica Gel RP18 F254S with eluent composition ethyl acetate methanol ammonia 85 10 5 showed PMMA spots at Rf 0.3. The synthesized PMMA with purity 99,3790 was used as reference standard for analyzing samples. Tablet samples containing PMMA and spiked samples were investigated by using GC MS method with capillary column HP 5MS 30 m x 0.25 mm i.d and run time less than 30 minutes. The chromatogram showed at 8.504 minutes with fragmentation pattern 58, 91, 121, 149 and 179 m z. "

"The aim of this study was to synthesize high luminescence materials containing the optimal combination of ternary europiumpicrate complex and matrices. The ternary europium-picrate-triethylene glycol (Eu-EO3-Pic) complex was doped in poly(methyl methacrylate), PMMA. The composites were impregnated in several matrices to form thin filmsvia spin coating technique. The microparticles of Eu-EO3-Piccomplex were prepared by reprecipitation-evaporation, then they were compared to analogous complex or microcomposite prepared by in-situ method. The Eu-EO3-Pic/PMMA microcomposites were characterized by fluorescence spectroscopy in acetone solution. The particle sizes distribution of microcomposites synthesized by reprecipitation-evaporation method (110.3 to 426.8 nm) were smaller compared to the microcomposites by in-situ method (641.7 nm). The PMMA was able to significantly enhance the fluorescence intensity of Eu-EO3-Pic microparticles. The fluorescence intensity of microcomposite by in situ-preparation was lower than that found in the microcomposites by reprecipitation-evaporation method. We also investigated the effect of different matrices on the photophysical properties. The effective intermolecular energy transfer from PMMA to the Eu-EO3-Pic complex would produce high sensitization efficiency. These microcomposites are very potential used as the emission material for organic light emitting devices."

"ABSTRAKDengan berkembangnya kemampuan rekayasa material, polimer blend menjadisalah satu metode untuk merekayasa material polimer yang penting karenaaplikasinya yang luas salah satunya usaha me-recycle limbah polimer. Telahdilakukan penelitian tentang pengaruh blending antara material polimer Poli(metilmetakrilat) (PMMA) regrind dengan Akrilonitril Butadiena Stirena (ABS).PMMA regrind merupakan limbah produksi berbentuk serpihan, berasal darilensa lampu motor yang cacat dan kemudian dihancurkan dengan mesin pencacah.Komposisi PMMA regrind yang ditambahkan kedalam ABS adalah 10%, 20%,30% dan 40% (% berat). ABS yang digunakan telah diidentifikasi persentasekomposisi monomernya dengan 1H-NMR. Proses blending menggunakan alatekstruder twin screw dengan setting parameter 210oC-240oC pada putaran 120rpm. Hasil blending ABS/PMMA dikarakterisasi sifat mekaniknya seperti tensilestrength, impact strength dan sifat termalnya dengan DSC serta morfologinyadengan SEM. Hasil analisis monomer ABS dengan 1H-NMR adalah akrilonitril9,26% ,butadiena 21,68% dan stirena 69,06%. Karakterisasi hasil blendingABS/PMMA menunjukkan bahwa semakin tinggi persentase PMMA yangditambahkan akan menaikkan nilai tensile strength material dan menurunkan nilaielongation dan impact strength-nya. Hasil DSC menyatakan blending tersebutimmiscible dan tidak compatible dilihat dari nilai Tg dari masing-masing blendingyang terdapat lebih dari satu Tg dan nilainya yang tidak berubah signifikan darinilai Tg penyusunnya yaitu ABS dan PMMA. Oleh karena itu, blending ABSdengan PMMA regrind dapat diaplikasikan untuk produk dengan kekuatanterhadap benturan dan fleksibilitas yang moderat seperti housing lampu kendaraanbermotor.

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ABSTRACT With the growing capabilities of materials engineering, polymer blend becomes auseful method to simulate polymer material. One example of it?s broadapplications is to recycle waste polymer. A research about the effects of blendingABS (Acrylonytrile Butadiene Styrene) with regrind-PMMA (PolymethylMethacrylate) has been done. The regrind-PMMA used were taken from the wasteproduction of housing lamp for automotive that has been through grindingprocess. The composition of regrind-PMMA added to the ABS is 10%, 20%, 30%and 40% from the total weight of mixture. The composistion of monomers insidethe ABS was previously identified by using 1H-NMR. Blending process is doneby using twin screw extruder which temperature was kept between 210oC-240oCon 120 rpm. The final blending product is characteristize by it?s mechanicalproperties such as tensile strength, impact strength, thermal properties (by usingDSC) and morphology properties (by using SEM). By using 1H-NMR, thecomposition of monomers inside ABS are 9,26% of acrylonitrile, 21,68% ofbutadiene and 69,06% of styrene. As the results of blending regrind-PMMA andABS is the higher percentage of regrind-PMMA added, the higher tensile strengthof the material, but in the other hand, the elongation and impact strenght arelower. DSC?s result shows that the blending is immicible and not compatible.Therefore, the blending of regrind-PMMA with ABS can be applied for producingnew product with moderate impact resistance and flexibility, such as housinglamp for automotive."

"Elektroda selektif ion (ISE) Kalium merupakan salah satu sensor kimia yangbanyak dikembangkan karena penting dan praktis dalam aplikasi biomedis. Prinsip kerjaISE yaitu dengan mengukur aktivitas ionik menggunakan metode potensiometri. ISEyang digunakan dalam penelitian ini adalah Screen Printed Electrode (SPE) , denganmenggunakan voltametri siklik (CV), lapisan polianilin diendapkan pada elektrodakarbon, dengan pemindaian mikroskop elektron. Polianilin (PANI) digunakan sebagaitransduser karena memiliki konduktivitas yang tinggi di dalam air dan mudah disintesis.Polimetil metakrilat – Butil Akrilat digunakan sebagai ion selektif membran (ISM) danvalinomisin digunakan sebagai ionofor selektif. Modifikasi dilakukan dengan metodepotensiometri melalui voltametri siklik. Hasil modifikasi ISE dikarakterisasimenggunakan Fourier-TransformInfraRed Spectroscopy (FTIR) dan Scanning ElectronMicroscopy (SEM). Uji performma analisis terhadap ion kalium dilakukan denganpengukuran linearitas, Limit of Detection (LOD), selektivitas, presisi dan akurasi.Persamaan yang didapat dari uji linearitas ,dengan y = - 61,119x + 407,46 dengan nilaiR2 sebesar 0,9924, yang menunjukkan bahwa nilai sensitivitas yang didapat dari ISEtermodifikasi yaitu sebesar 58,175 mV, dan limit of detection (LOD) pada penelitian inisebesar 10-5,4866 dimana ion Kalium dapat terdeteksi.ISE memmiliki selektifitas yang baikdengan nilai koefisien selektifitas masing- masing terhadap ion Na sebesar 3,659 x 10-4,Mg sebesar 1,719 x 10-10, dan Ca sebesar 2,351 x 10-9

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Potassium ion selective electrode (ISE) is one of the chemical sensors that has been

widely developed because it is important and practical in biomedical applications. The

working principle of ISE is to measure ionic activity using the potentiometric method.

The ISE used in this study is a Screen Printed Electrode (SPE), using cyclic voltammetry

(CV), a polyaniline layer is deposited on a carbon electrode, by scanning electron

microscopy. Polyaniline (PANI) is used as a transducer because it has high conductivity

in water and is easy to synthesize. Polymethyl methacrylate – Butyl Acrylate was used as

an ion selective membrane (ISM) and valinomycin was used as a selective ionophore.

Modification is done by potentiometric method through cyclic voltammetry. The

modified ISE was characterized using Fourier-Transform InfraRed Spectroscopy (FTIR)

and Scanning Electron Microscopy (SEM). The analysis performance test of potassium

ion was carried out by measuring linearity, Limit of Detection (LOD), selectivity,

precision and accuracy. The equation obtained from the linearity test, with y = -61.119x

+ 407.46 with an R2 value of 0.9924, which indicates that the sensitivity value obtained

from the modified ISE is 58.175 mV, and the limit of detection (LOD) in this study of

10-5.4866 where Potassium ions can be detected. ISE has a good selectivity with a

selectivity coefficient of 3.659 x 10-4 for Na ions, 1.719 x 10-10 for Mg, and 2.351 x 10-

9 for Ca."

"Elektroda selektif ion (ISE) Kalium merupakan salah satu sensor kimia yang banyak dikembangkan karena penting dan praktis dalam aplikasi biomedis. Prinsip kerja ISE yaitu dengan mengukur aktivitas ionik menggunakan metode potensiometri. ISE yang digunakan dalam penelitian ini adalah Screen Printed Electrode (SPE) , dengan menggunakan voltametri siklik (CV), lapisan polianilin diendapkan pada elektroda karbon, dengan pemindaian mikroskop elektron. Polianilin (PANI) digunakan sebagai transduser karena memiliki konduktivitas yang tinggi di dalam air dan mudah disintesis. Polimetil metakrilat – Butil Akrilat digunakan sebagai ion selektif membran (ISM) dan valinomisin digunakan sebagai ionofor selektif. Modifikasi dilakukan dengan metode potensiometri melalui voltametri siklik. Hasil modifikasi ISE dikarakterisasi menggunakan Fourier-TransformInfraRed Spectroscopy (FTIR) dan Scanning Electron Microscopy (SEM). Uji performma analisis terhadap ion kalium dilakukan dengan pengukuran linearitas, Limit of Detection (LOD), selektivitas, presisi dan akurasi. Persamaan yang didapat dari uji linearitas ,dengan y = - 61,119x + 407,46 dengan nilai R2 sebesar 0,9924, yang menunjukkan bahwa nilai sensitivitas yang didapat dari ISE termodifikasi yaitu sebesar 58,175 mV, dan limit of detection (LOD) pada penelitian ini sebesar 10-5,4866 dimana ion Kalium dapat terdeteksi.ISE memmiliki selektifitas yang baik dengan nilai koefisien selektifitas masing- masing terhadap ion Na sebesar 3,659 x 10-4 ,Mg sebesar 1,719 x 10-10, dan Ca sebesar 2,351 x 10-9.

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Potassium ion selective electrode (ISE) is one of the chemical sensors that has been widely developed because it is important and practical in biomedical applications. The working principle of ISE is to measure ionic activity using the potentiometric method. The ISE used in this study is a Screen Printed Electrode (SPE), using cyclic voltammetry (CV), a polyaniline layer is deposited on a carbon electrode, by scanning electron microscopy. Polyaniline (PANI) is used as a transducer because it has high conductivity in water and is easy to synthesize. Polymethyl methacrylate – Butyl Acrylate was used as an ion selective membrane (ISM) and valinomycin was used as a selective ionophore. Modification is done by potentiometric method through cyclic voltammetry. The modified ISE was characterized using Fourier-Transform InfraRed Spectroscopy (FTIR) and Scanning Electron Microscopy (SEM). The analysis performance test of potassium ion was carried out by measuring linearity, Limit of Detection (LOD), selectivity, precision and accuracy. The equation obtained from the linearity test, with y = -61.119x + 407.46 with an R2 value of 0.9924, which indicates that the sensitivity value obtained from the modified ISE is 58.175 mV, and the limit of detection (LOD) in this study of 10-5.4866 where Potassium ions can be detected. ISE has a good selectivity with a selectivity coefficient of 3.659 x 10-4 for Na ions, 1.719 x 10-10 for Mg, and 2.351 x 10- 9 for Ca."