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"Metilamina yang disintesis dari metanol dan amoniak diteliti pada studi ini menggunakan katalis garam parsial kalium heteropoli (Cs3-xHxPW12O40 disingkat KPW). KPW dipreparasi dari asam heteropoli dan kalium karbonat dengan metode pertukaran ion. Reaksi dilakukan pada 600~800K dan tekanan atmosfir menggunakan reaktor alir kontinyu pada W/F=0,1~0,9g-kat.mnt./cc. Analisis konsentrasi produk dan reaktan menggunakan gas kromatografi sedangkan karakterisasi struktur katalis menggunakan XRD (X-ray diffraction) dan adsorbsi isothermal untuk menentukan ukuran pori katalis Hasil penelitian menunjukkan bahwa pertukaran ion H dengan K untuk membentuk garam kalium heteropoli menyebabkan perubahan interstisial space yang teramati dengan berubahnya lattice constant dari kristal katalis. Ukuran pori yang lebih kecil dari Trimetilamina (TMA) akan tetapi lebih besar dari Monometilamina (MMA) dan Dimetilamina (DMA) menyebabkan TMA menjadi tidak diproduksi. Kristal KPW bersifat rigid sehingga pori yang terbentuk tidak berubah sepanjang reaksi, sebaliknya kristal (NH4)3PW12O40 tidak rigid dan ukuran pori mudah berubah tergantung dari ukuran metilamina yang teradsorbsi sehingga katalis ini menjadi tidak selektif terhadap metilamina yang berukuran kecil.

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Role of K3-xHxPW12O40 as a Catalyst in Selective Catalysis of Methylamine Synthesis from Ammonia and Methanol. Synthesize of methylamine from methanol and ammonia was studied in this research work using a partially potassium heteropoly salt (K3-xHxPW12O40 abbreviated as KPW) as a catalyst. KPW was prepared from heteropoly salt and potassium carbonate by using ion exchange method. The reaction was conducted at 600 ~ 800K and at the atmospheric pressure. Reactor used was a continue flow reactor with W/F=0,1~0,9g-kat.mnt./cc. Concentration of reactants and products were analyzed by gas chromathography while catalyst structure was observed by XRD (X-ray diffraction). Isothermal adsorption method was used for determining catalyst pore size. The result showed that ion exchange between H ion in zeolit with K ion produced potassium heteropoly salt that caused the change of interstitial space. The change of interstitial space was observed by the change of the lattice constant of the catalyst crystal. Trimethylamine(TMA) has molecule size smaller than catalyst pore size but bigger than molecular size of Dimethylamine (DMA) and Monimethylamine (MMA). This phenomenon caused the suppression of TMA formation. KPW has a rigid crystal structure and stabil during reaction. On the other hand, crystal structure of a non selective catalyst (NH4)3PW12O40 was not rigid and its pore size is easy to change depending on the product molecule size."

"Cervical cancer is the second most frequently occurring cancer among females all over the world. Since the best strategy against cancer is to kill the cancer cells without endangering the normal cells, discovering a potentially selective anticancer agent from plants has become very challenging for researchers worldwide. A previous study on Anredera cordifolia, known as binahong in Indonesia, revealed its cytotoxic activity on HeLa cervical cancer cells with IC50 75 µg/mL. However, the selectivity of the chemical agent and its molecular target was not investigated. Thus, this study was aimed at determining the selectivity of ethanolic extract of Anredera cordifolia leaf (EAC) on Vero cells and its molecular target on HeLa cells. The extracts were prepared by macerating A. cordifolia leaf powder in 70% ethanol. The viability of Vero cells was assessed using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. While the cell cycle of HeLa cells was analyzed using the flow cytometry, the molecular target of the extract was investigated by using the immunocytochemical staining. The results exhibited the selective cytotoxicity of EAC on HeLa cells compared to Vero cells with a Selectivity Index (SI) of 17.36. It arrested the G1/S phase of the cell cycle and suppressed the Bcl–2 expression, the anti-apoptotic protein, which also regulates the cell cycle. These findings confirmed the use of A. cordifolia leaf extract as a promising anticancer agent against cervical cancer, particularly the HeLa cells."

"Intervensi yang dilakukan menggunakan Cognitive Behaviour Therapy dalam menangani selective eating problem pada anak laki~1aki berusia sembilan tahurt Tujuan intervensi adalah untuk mengidentiiikasi dan rnengubah distorsi kognitif anak tentang makanan sehingga anak diharapkan mampu menemukan makanan lain yang dapat dikonsumsi olehnya. Intervensi dilakukan dalam 15 sesi yang berlangsung dalam jangka walcu dna bulan. Sesi terbagi atas dua bagian, yaitu sesi intervensi kognitif untuk mengubah distorsi kognitif pada anak scrta scsi perilaku dimana anak berhadapan langsung dengan makanan dan mcngaplikasikan materi yang diclapatkan pada sesi kognitifi Setelah 15 sesi intervensi selesai dilakukan, terlihat bahwa anak dapat menemulcan dan memahami distorsi pikirannya tentang makanan sehingga akhimya anak mampu berpikir sccara Iebih seimbang. Kondisi tersebut akhimya berpengaruh terhadap perilakunya, yaitu anak bersedia mencoba makan dan menemukan satu jenis makanan yang dapat dikonsumsi sebagai menu makan siang atau makan malam. Beberapa saran yangdapat diberikan antara lain: orangtua sebaiknya tidak memaksa dan mengancam anak untuk makan. Orangtua juga pcrlu lebih bersabar dan membedkan pujian untuk setiap perlgembangan positif serta berdiskusi bersama dengan anak dalam menentukan menu makan siang atau makan malam.

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The intervention has been done using Cognitive Behavior Therapy to treat a 9 years old boy with selective eating problem. The objective of the intervention are to identify and change the child’s cognitive distortion about food so that he is expected to be able to find the other food he can consume. Intervention was implemented in 15 sessions during two months period. Sessions were divided into two segments, consisting of cognitive intervention session to change the child’s cognitive distortion and behavior session where he was directly faced with the food and applied the material given in cognitive session. After 15 sessions were done, it can be seen that the child can recognize and understand their cognitive distortion about food in such a way- that he can be able to think more proportionately. That condition on eventually affects his behavior, i.e., he is willing to try the food and find one type of food that can be'eaten as lunch or dinner menu. Some recommendations given include : parents should not force and threaten their child to eat. Parents also need to be more patient and give compliments for each of positive improvement, and also discuss together with their child to decide the lunch or dinner menu that the child desires."

"Pengolahan bijih nikel laterit untuk menghasilkan feronikel memerlukan konsumsi energi yang tinggi. Sehingga perlu teknik pengolahan bijih nikel laterit terutama yang berkadar rendah agar tetap ekonomis. Reduksi selektif bijih nikel laterit diaggap sebagai proses yang potensial untuk menghasilkan nikel berkadar tinggi pada feronikel. Reduksi selektif terjadi karena penambahan sejumlah aditif pada bijih nikel laterit kemudian dilakukan separasi magnetik. Pada penelitian ini, digunakan aditif natrium karbonat, natrium klorida dan natrium sulfat serta 5 arang cangkang sawit sebagai reduktor. Reduksi dilakukan pada variasi temperatur 950, 1050 dan 1150 oC selama 60 menit. Kemudian dilakukan metode separasi magnetik basah dengan kekuatan magnet 500 Gauss untuk memisahkan konsentrat yang bersifat magnetik dan tailing. Karakterisasi bijih laterit hasil reduksi dilakukan menggunakan X-ray Diffraction XRD , mikroskop optik dan Scanning Electron Microscope SEM yang dilengkapi Energy Dispersive X-ray Spectroscopy EDS serta konsentrat feronikel dan tailing diidentifikasi menggunakan X-ray Fluororescene XRF. Hasil percobaan menunjukkan bahwa penambahan aditif menghasilkan peningkatan kadar dan recovery nikel serta recovery besi pada konsentrat jika dibandingkan dengan bijih reduksi tanpa penambahan aditif. Penambahan 15 aditif natrium sulfat dapat meningkatkan kadar dan recovery nikel hingga mencapai 5,3 dan 83,7 pada temperatur reduksi 1150 oC selama 60 menit. Pada penambahan 5 aditif natrium karbonat dan natrium klorida menghasilkan recovery nikel optimum sebesar 73,1 dan 72,8. Peningkatan temperatur reduksi hingga 1150 oC selama 60 menit berpotensi meningkatkan ukuran partikel feronikel, dengan penambahan dosis 10 natrium sulfat, natrium karbonat dan natrium klorida dihasilkan rata-rata ukuran partikel feronikel sebesar 30,6 mm, 12,8 mm dan 8,0 mm hingga 30,6 mm. Partikel feronikel mengalami aglomerasi seiring dengan peningkatan temperatur pada penambahan aditif yang memberikan kondisi yang menguntungkan untuk migrasi dan agregasi Ni dan Fe.

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The processing of nickel laterite to produce ferronickel requires high energy consumption. Therefore, it needs low cost technology in mineral processing the low grade nickel laterite to keep it economically. Selective reduction of nickel laterite ore is a potential method for producing high grade ferronickel. Selective reduction is performed due to the addition of additives to lateritic nickel ore and followed by magnetic separation. In this study, the additives were sodium carbonate, sodium chloride and sodium sulphate and 5 palm shell charcoal were used as reducing agents. The temperature reduction was carried out at 950 and 1150 oC for 60 min. Magnetic separation used in this study was a wet magnetic separation with 500 Gauss and the magnetic product magnetic product that was resulted from the magnetic separation was ferronickel concentrate. The characterization of reduced ore was performed by using by X ray Diffraction XRD , optical microscope and Scanning Electron Microscope SEM with Energy Dispersive X ray Spectroscopy EDS and ferronickel concentrate was identified by X ray Fluororescene XRF.

The results showed that the addition of additives was significantly affected to the increasing of nickel grade, nickel recovery and iron recovery at concentrate than the reduced ores without additives. When the sodium sulfate dosage was increased to 15 at 1150 oC for 60 min, the nickel grade and nickel recovery were increased to 5.3 and 83.7 , respectively. By the increasing of the addition of sodium carbonate and sodium chloride up to 5 , the yielded optimum nickel recovery was 73.1 and 72.8 , respectively. The increasing of reduction temperature to 1150 oC for 60 min potentially increased the particle size of ferronickel up to 30.6 m by the addition of a 10 sodium sulfate. In the presence of sodium carbonate and sodium chloride result on the average of ferronickel particle size approximately 12.8 and 8.0 m, respectively. The ferronickel particle was agglomerated with increasing reduction temperature and addition additives and it provides favorable conditions for the migration and aggregation of Ni and Fe."

"Latar Belakang: Di Indonesia, belum diketahui berapa jumlah kadar ion fluor yang terdapat pada pasta gigi dewasa. Tujuan: Mengetahui kadar ion fluor yang terdapat pada pasta gigi dewasa dan membandingkan kadar ion fluor hasil analisis dengan kadar ion fluor yang tertera pada kemasan pasta gigi dewasa dan kesesuaiannya dengan standar dari EBD dan regulasi BPOM. Metode: Penelitian ini merupakan penelitian studi analitik laboratorik, yaitu analisis in vitro terhadap total fluoride(TF) dari 10 pasta gigi dewasa yang dijual di Indonesia dibeli dengan kelipatan 3 dari toko berbeda dianalisa mengunakan alat fluoride ion selective electrode. Hasil: Kadar ion fluor hasil analisis berbeda bermakna dengan kadar ion fluor yang tertera pada kemasan pada semua sampel. 5 dari 10 sampel yang diuji mengandung kadar ion fluor dibawah 1000 ppm F, sedangkan 4 sampel lainnya mengandung kadar ion fluor diatas 1500 ppm F. Hanya terdapat satu sampel yang mengandung kadar fluor yang sesuai standar dari EBD dan regulasi BPOM. Kesimpulan: Terdapat pasta gigi di Indonesia yang tidak menyajikan kadar fluor dengan jumlah yang efektif untuk mengontrol karies

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Background: In Indonesia, no information is available regarding the fluoride ion content in adult's toothpastes.

Objective: To enumerate fluoride content in adult's toothpastes marketed in Indonesia and to determine if the fluoride content is accordance with the information provided on the packaging and following to the standard from evidence based dentistry and BPOM regulation.

Methods: This research is an analytical laboratory study, in vitro analysis of total fluoride (TF)in 10 adult's toothpastes in Indonesia purchased in triplicate from different store analysed using ion selective electrode.

Result:The available fluoride content in adult's toothpastes found in analysis did not match the fluoride content provided on the packaging for all samples. 5 out of 10 toothpaste contain fluoride less than 1000 ppm F while the other 4 contain fluoride greater than 1500 ppm F. Only one toothpaste contain fluoride which match the standard from evidence based dentistry and BPOM regulation.

Conclusion: Most adult's toothpastes marketed in Indonesia do not present available fluoride concentration for caries control."

"Skripsi ini membahas mengenai pemanfaatan jasa informasi terbaru dan terseleksi di perpustakaan BAKOSURTANAL. Tujuannya adalah untuk mengetahui apakah jasa informasi terbaru dan terseleksi dimanfaatkan pengguna untuk menunjang kegiatan penelitian dan kendala apa yang dihadapi pengguna dalam memanfaatkan jasa tersebut. Penelitian ini adalah penelitian deskriptif dengan pendekatan kuantitatif melalui penyebaran kuesioner dalam pengumpulan data. Populasi dalam penelitian ini adalah seluruh pengguna yang dikirimkan melalui e-mail. Sampel yang digunakan dengan menggunakan rumus Slovin, dengan teknik pengambilan sampel acak berlapis (stratified random sampling), sehingga sampel yang diambil 93 responden dengan metode penarikan sampel acak berdasarkan masing-masing pusat atau balai. Teknik analisis data melalui beberapa tahap yaitu penyuntingan, pengkodean, penyusunan dan perhitungan data dengan SPSS 17.0. Hasil penelitian ini menggambarkan bahwa jasa informasi terbaru dan terseleksi dimanfaatkan pengguna untuk menambah pengetahuan saja dan kendala yang dihadapi ketika memanfaatkan jasa ini adalah keterbatasan waktu. Saran penelitian ini, yaitu perpustakaan perlu mengembangkan jasa informasi terbaru dan terseleksi dalam forum diskusi ilmiah; perlu adanya evaluasi bidang minat pengguna supaya informasi yang diberikan relevan dan dibutuhkan dengan segera.

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The Focus of this study is about the use of current awareness service and selective dissemination information at library BAKOSURTANAL. The purpose of this study is to understand whether the users use the current awareness service and selective dissemination information for research and to understand their difficulties in using theses services. The research method to make this study is a descriptive research with quantitative method by distributing questioner in collecting the data The population in this research is the library user who was sent by e-mail. I used Slovin formula to make the sample by stratified random sampling therefore the sample taken, 93 respondents with stratified random sampling are based on each centers and offices. The techniques of data analyze use three steps which are codifying, compiling, and data counting with SPSS 17.0. By comparing to the result of this research, it is informed that the current awareness service and selective dissemination information are only used to enrich their knowledge and their difficulty is the limit time. The result of this research suggests the library to improve current awareness service and selective dissemination information in a discussion forum; it is important that there is a user?s interest in order to give relevant information and also make the information immediately needed."

"Titanium dan paduannya menjadi salah satu material pilihan untuk manufaktur beragam objek, terutama pada implan karena sifat mekanik, biokompatibilitas, dan ketahanan korosinya. Titanium dan paduannya dapat difabrikasi menggunakan beragam metode seperti Selective Laser Melting yang memakan waktu singkat dan waste-nya yang sedikit namun kekurangannya adalah getas. Salah satu cara meningkatkan ketangguhan dan keuletannya adalah dengan perlakuan panas. Hasil penelitian ini menunjukkan efek perlakuan panas pada suhu 900 C selama 2 jam menghasilkan mikrostruktur dominan berfasa α-Ti kolumnar yang memiliki nilai kekerasan 656 HV, sedangkan HT pada suhu 900 C selama 1 jam dilanjut di 550 C selama 2 jam menghasilkan mikrostruktur dan hasil XRD yang mengindikasikan campuran α dan β-Ti dengan kenaikan kekerasan menjadi 665 HV. Perlakuan panas yang lebih lama yaitu pada 900 C selama 2 jam dan 550 C selama 2 jam dan 900 C selama 2 jam dilanjut dengan 550 C selama 3 jam menunjukkan mikrostruktur dominan berfasa α-Ti ekuiaksial, dengan nilai kekerasannya menurun menjadi 622 HV dan 593 HV.

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Titanium and its alloy have become a material of choice for manufacturing various objects, particularly implants, due to their mechanical properties, biocompatibility, and corrosion resistance. Titanium and its alloys can be fabricated using various methods such as Selective Laser Melting, which is time-efficient and produces minimal waste, though its drawback is brittleness. The closest approach to enhancing the toughness and ductility of the SLM product is through post- processing by heat treatment. This study shows that heat treatment process which is done at 900°C for 2 hours holding resulting in a microstructure dominated by columnar α-Ti phase with a hardness value of 656 HV. Another heat treatment process is performed at 900° for 1 hour holding followed by 550°C for 2 hours holding, resulting in a microstructure and XRD which indicates a mixture of α and β-Ti with an increase in hardness to 665 HV. A longer heat treatment process is conducted at 900°C for 2 hours holding followed by 550°C for 3 hours holding, which shows a domination of equiaxed α-Ti phase in its microstructure, with a decrease in hardness to 622 HV and 593 HV."

"Imprinted polymer untuk ion Pb2+ (Pb-IIP) disintesis melalui proses self assembly antara monomer fungsional 4-vinil piridin dan asam metakrilat serta ion Pb2+ sebagai template. Kompleks template/monomer yang terbentuk dipolimerisasi menggunakan metode polimerisasi suspensi dengan pengikat silang etilen glikol dimetakrilat (EGDMA) dan inisiator 2,2?-azobis isobutironitril (AIBN). Proses leaching menggunakan HNO3 0,5 M dilakukan pada Pb-IIP hasil sintesis untuk mengelusi ion Pb2+, sehingga didapatkan rongga spesifik yang berfungsi sebagai situs pengenalan. Keberhasilan sintesis polimer dianalisis menggunakan FTIR. Puncak gugus C=C ulur vinil pada panjang gelombang 1630 cm-1 tidak muncul menandakan putusnya ikatan rangkap akibat adanya proses polimerisasi. Hasil karakterisasi EDX menunjukkan bahwa pengompleksan dan pengelusian ion Pb2+ berhasil dilakukan yang dikonfirmasi dengan munculnya intensitas Pb sebelum dilakukan elusi dan tidak munculnya intensitas Pb setelah dilakukan elusi. Hasil karakterisasi menggunakan PSA menunjukkan distribusi ukuran partikel Pb-IIP yaitu 34,5μm. Adsorben Pb-IIP diuji sifat adsorpsi serta desorpsinya dan diperoleh persen adsorpsi di atas 99% dan persen desorpsi sebesar 92,45%. Sebagai pembanding, pada non imprinted polymer (NIP) diperoleh persen adsorpsi sebesar 21,63% dan persen desorpsi sebesar 52,57%. Pb-IIP memiliki persen adsorpsi yang lebih besar terhadap Pb2+ dibandingkan dengan ion logam lainnya yaitu Ni2+, Co2+, Cu2+, dan Fe3+. Kemampuan adsorpsi maksimum pada Pb-IIP dapat dicapai saat pH 7 dan waktu kontak 60 menit. Pb-IIP dapat diaplikasikan pada sampel air di lingkungan dengan % recovery sebesar 110%.

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An imprinted polymer for Pb2+ ion (Pb-IIP) was synthesized by self-assembly method using 4-vinyl pyridine, methacrylic acid as functional monomer and Pb2+ ion as template. Template/monomer complex was polymerized using a suspension polymerization method with crosslinker ethylene glycol dimethacrylate (EGDMA) and initiator 2,2'-azobis isobutyronitrile (AIBN). Pb-IIP was leached using 0.5 M HNO3 to remove Pb2+ ion that would produce the specific cavity as a recognition site. The success of synthesis was analyzed using FTIR resulting the absence of peak for C=C stretching at 1630 cm-1 indicated the bond rupture due to the polymerization process.

EDX characterization indicated that complexing and leaching of Pb2+ ion were successfully confirmed by the appearance of Pb elements prior to elution and disappearance of Pb elements after elution. PSA characterization showed the particle size distribution of Pb-IIP was 34.5 μm. Adsorption and desorption process were performed on Pb-IIP adsorbent obtained > 99% for adsorption and 92.45% for desorption. NIP adsorbent used for comparison with Pb-IIP resulting 21.63% for adsorption and 52.57% for desorption. Pb-IIP had a better adsorption towards Pb2+ compared with other metal ions such as Ni2+, Co2+, Cu2+, and Fe3+. The maximum adsorption capacity of Pb-IIP could be achieved when the pH was 7 and contact times was 60 minutes. Pb-IIP could be applied to environmental water samples resulting % recovery 110%."

"ABSTRAKKebutuhan CaCO3 murni (>98%) baik di dunia maupun di Indonesia terus meningkat. Untuk memenuhi kebutuhan ini Indonesia mengimpor CaCO3 murni dalam jumlah yang cukup besar tiap tahunnya. Hal ini sangat disayangkan mengingat Indonesia memiliki sumber daya alam yang melimpah. Salah satu sumber daya alam yang melimpah di Indonesia adalah batuan dolomit. Dalam upaya meningkatkan nilai tambah mineral dolomit, perlu dilakukan kajian teknologi yang dapat diaplikasikan secara tepat dalam mengolah mineral dolomit tersebut. Penelitian ini bertujuan untuk dapat memisahkan kandungan CaCO3 dalam dolomit sehingga menghasilkan CaCO3 dengan tingkat kemurnian yang tinggi agar dapat memenuhi kebutuhan masyarakat Indonesia. Pada penelitian ini dilakukan modifikasi proses leaching yaitu berupa selective leaching dimana pada metode ini digunakan HCl dalam konsentrasi yang sangat rendah sehingga hanya ion Ca yang larut dalam HCl. Karakterisasi yang dilakukan meliputi komposisi dolomit dan produk CaCO3 menggunakan XRF dan metode penimbangan. Selective leaching dengan menggunakan HCl dilakukan pada variasi konsentrasi, waktu, rasio, dan kecepatan pengadukan. Kondisi optimum untuk menghasilkan CaCO3 dengan kemurnian diatas 98% didapat dengan menggunakan HCl 0.05M sebanyak 100mL selama 1 jam dan dilakukan tanpa pengadukan.

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ABSTRACTThe needs of pure CaCO3 (>98%) both in the world and in Indonesia continues to increase every year. To meet this need, Indonesia imports CaCO3 in large quantities each year. This is very unfortunate because Indonesia has abundant natural resources, and one of them is dolomite. In an effort to increase the value of dolomites in Indonesia, it is necessary to study technologies that can be applied appropriately in processing the dolomites. This study aims to produce pure CaCO3 from dolomites in order to fulfill the needs in Indonesia. In this research, leaching process is modified into selective leaching. In this method, the concentrations of HCl that being used is very low that only Ca ion is dissolved in HCl. Characterization of dolomites composition is conducted by using XRF. Selective leaching using HCl performed at various concentrations, times, ratios, and stirring speeds. The optimum conditions to produse CaCO3 with a purity above 98% is obtained by using 100mL of 0.05M HCl for 1 hour and is done without stirring."