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"ABSTRAKLawson atau 2-hydroxy-1,4-naphtaquinone adalah senyawa yang berasal dari 1,4- naphtaquinone yang dilaporkan memiliki manfaat yang baik dalam hal uji aktivitas biologis dan farmakologi seperti antimikroba, antiretik, antioksidan, dan aktivitas baik untuk penderita tuberkulosis. Dalam skala produksi senyawa Lawson dapat meningkatkan waktu dan efisiensi dalam pembentukan senyawa antioksidan dengan menggunakan katalis asam amino (L-proline). Dalam penelitian ini asam amino (L-proline) yang digunakan sebagai katalisator untuk sintesis senyawa Lawson melibatkan pereaksi benzaldehida, sinamaldehida dan 2-hidroksibenzaldehida. Karakterisasi Katalis L-prolin dan sintesis senyawa Lawson dilakukan menggunakan FT-IR, GC-MS dan UV-Vis, Kromatografi Lapis Tipis dan uji antioksidan dengan metode DPPH.ABSTRACTLawson or 2-hydroxy-1,4-naphtaquinone is a compound derived from 1,4-naphtaquinone which is reported to have good benefits in terms of biological and pharmacological activity tests such as antimicrobial, antiretic, antioxidant, and good activity for tuberculosis sufferers. In the production scale of Lawson compounds, it can increase the time and efficiency in the formation of antioxidant compounds by using an amino acid catalyst (L-proline). In this study, the amino acid (L-proline) which is used as a catalyst for the synthesis of Lawson compounds involves the reagents benzaldehyde, cinamaldehyde and 2 hydroxybenzaldehyde. Characterization of L-proline catalyst and synthesis of Lawson compounds were carried out using FT-IR, GC-MS and UV-Vis, Thin Layer Chromatography and antioxidant assays using the DPPH method."

"Oleic imidozaline is one of the nitrogen containing heterocyclic compounds that has been widely used as commercial corrosion inhibitor, especially in minizing the carbon dioxcide induced corrosion process in oilfield mining....."

"Proses sintesis LiFePO 4/V/C dilakukan untuk membuat katoda baterai lithium ion. Sintesis diawali dengan membuat LiFePO4 melalui proses hidrotermal dengan bahan dasar LiOH, NH4H2PO4, dan FeSO4.7H2O. Setelah proses sintesis, LFP kemudian ditambahkan variasi vanadium dan karbon aktif sekam padi. Ketiga bahan dicampur menggunakan ball-miller kemudian dikarakterisasi analisis termal STA untuk menetukan temperatur sintering. Proses sintering dilakukan pada temperatur 850 C selama 4 jam. Hasil sintering kemudian dikarakterisasi dengan difraksi sinar-X XRD dan morfologi permukaan dianalisa dengan menggunakan mikroskop elektron SEM. Hasil karakterisasi dengan XRD menunjukkan terbentuknya fasa LiFePO4/V/C. Hasil SEM menunjukkan perbedaan morfologi penambahan vanadium dan karbon aktif. Proses pembuatan baterai dilakukan dengan bahan-bahan hasil sintesis. Pengujian konduktifitas dilakukan dengan menggunakan EIS. Hasil EIS menunjukkan bahwa dengan penambahan karbon aktif sekam padi memiliki konduktifitas yang lebih besar dibandingkan karbon gula dan carbon black. Hasilnya yaitu karbon aktif sekam padi dapat digunakan sebagai pelapis karbon pada katoda baterai lithium ion.

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Use of carbon pyrolized from rice husk in the synthesis of LiFePO4 V C used as lithoum ion battery cathode has been carried out. The synthesis was begun by syntesizing LiFePO4 LFP via hydrothermal route using the precursors of LiOH, NH4H2PO4, and FeSO4.7H2O. The as synthesized LFP was then added with variations of vanadium and a fix composition of activated carbon using rice husk as the resource of the carbon. These three ingredients were mixed using a ball miller and was characterized using thermal analyzer to determine the transition temperature from which temperature 850 C was obtained. The LiFePO4 V C was characterized using X ray diffraction XRD whereas the surface morphology was analyzed using scanning electron microscope SEM equipped with energy dispersive X ray spectroscopy EDX.

XRD results show that the LiFePO4 V C has been formed, whereas SEM results showed a difference in morphology of vanadium and activated carbon addition. The battery were prepared from the as synthesized materials and was tested using electrical impendance spectroscopy EIS. EIS results showed that the materials with addition of activated carbon from the rice husk has greater conductivity than that of pure LFP. This prove that the activated carbon from the rice husk can be used as a cheap carbon resource for developing lithium ion battery cathode."

"ABSTRAKSintesis LiFe1-0.5Mn0.5PO4/V/C sebagai katode baterai ion litium telah berhasil dilaksanakan. Material LiFe1-0.5Mn0.5PO4/V/C disintesis dengan prekursor intermediat garam besi yang terdiri dari FeSO4.7H2O, dan NH4H2PO4, prekursor LiOH, prekursor MnSO4.H2O, prekursor NH4VO3, serta prekursor C6H8O7. Prekursor intermediat garam besi disintesis dengan variasi kondisi pH meliputi suasana asam (pH 2), netral (pH 7), dan basa (pH 10), metode pemanasan yang digunakan, serta penambahan perlakuan ultrasonik. Hasil penelitian menunjukkan bahwa kondisi pH sintesis akan mempengaruhi morfologi serta struktur kristal senyawa intermediat yang dihasilkan. Morfologi partikel dari seri asam cenderung berbentuk bulat ataupun oktahedral, seri netral cenderung berbentuk persegi panjang, sementara dari seri basa cenderung berbentuk lembaran. Struktur kristal seri asam menyerupai mineral lipscombite, sedangkan struktur kristal seri netral dan basa memiliki struktur garam besi fosfat. Perlakuan ultrasonik juga memberikan pengaruh terhadap morfologi serta struktur kristal senyawa intermediat yang dihasilkan. Morfologi dari sampel yang dikenai perlakuan ultrasonik cenderung berbentuk oktahedral, sementara durasi perlakuan ultrasonik mempengaruhi ukuran kristalit material. Proses pemanasan mempengaruhi morfologi serta struktur kristal senyawa intermediat yang dihasilkan. Proses pemanasan tanpa metode hidrotermal menghasilkan partikel yang cenderung beragregat. Hasil pengujian memperlihatkan sampel katode yang memiliki konduktivitas optimum didapatkan dari sampel LiFe1-0.5Mn0.5PO4/V/C yang disinter dengan tube furnace sebesar 5.6870 x10-5 S.cm-1, dengan tegangan kerja serta kapasitas pengisian optimum dalam sistem baterai R2032 dengan susunan [Li|1 M LiPF6/EC-DMC| LiFe1-0.5Mn0.5PO4/V/C] masing-masingnya 4.7 V dan 5.6 mAh.g-1.

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ABSTRACTSynthesis and characterization of LiFe1-0.5Mn0.5PO4/V/C used as lithium ion battery cathode has been successfully conducted. The LiFe1-0.5Mn0.5PO4/V/C composite was synthesized using iron salt intermediate precursors, which consist of FeSO4.7H2O, and NH4H2PO4, LiOH precursor, MnSO4.H2O precursor, NH4VO3 precursor and C6H8O7 precursor. Iron salt intermediate precursors were synthesized at various variable including variations in pH conditions acidic atmosphere (pH 2), neutral (pH 7), and alkaline (pH 10), heat treatments, and the use ultrasonic treatment. The results show that the pH synthesis conditions affect the morphology and crystal structure of the intermediate compounds produced. The morphology of iron salt intermediates in acidic condition was round and octahedral, in neutral condition is rectangular, and in alkaline condition is in sheet form. The crystal in acidic condition favored lipscombite structures, while the neutral and alkaline conditions favored phosphate iron salt structure. The ultrasonic treatment affected morphology and crystal structure of the intermediate compounds produced. The samples subjected to ultrasonic treatment formed an octahedral structure. Heat treatment also affected the morphology and crystal structural of the intermediate compounds produced. Heat treatment without hydrothermal treatment produced aggregated particles. In this work, the best conductivity of the cathode was obtained from LiFe1-0.5Mn0.5PO4/V/C sintered with tube furnace at 5.6870 x10-5 S.cm-1 and a working voltage and charge discharge in R2032 coin cell battery [Li|1 M LiPF6/EC-DMC| LiFe1-0.5Mn0.5PO4/V/C] of 4.7 V and 5.6 mAh.g-1, respectively."

"Sintesis menggunakan kombinasi metode solution combustion synthesis (SCS) dan solid state telah dilakukan dan diuji coba untuk mendapatkan katode baterai ion litium LiNi0,8Mn0,1Co0,1- xMoxO2/C dengan prekursor LiNO3, Ni(NO)3.6H2O, Mn(NO3)2.4H2O, Co(NO3)2.6H2O, (NH4)6Mo7O24, dan CH4N2O sebagai bahan bakar dengan dilarutkan dengan aquades dan diaduk menggunakan hot plate magnetic stirrer pada temperatur ruangan. Larutan dipanaskan pada temperature 100oC selama 1 jam hingga 200oC selama 2 jam hingga terbentuk pasta cokelat. Pemanasan lanjutan dilakukan pada muffle furnace pada temperature 500oC selama 2 jam, dan kalsinasi pada temperature 900oC selama 3 jam. Super-p carbon black ditambahkan sebagai adisi sebanyak 0,5 wt% dan dicampurkan dengan serbuk NMC 811 menggunakan agathe mortar selama 1 jam dan kalsinasi pada 300oC selama 3 jam. Serbuk berwarna hitam hasil sintesis dianalisis mikroskop elektron (SEM) untuk melihat morfologi, Hasil SEM menunjukkan sampel hasil sintesis memiliki ukuran dengan kisaran 0,1-1,55 µm. uJI difraksi sinar-X (XRD) untuk melihat kristalinitas dan menunjukkan bahwa terjadi pergeseran puncak 2θ ke arah kanan karena pengaruh oksida logam yang terbentuk. Analisis elektrokimia dilakukan dengan impedansi elektrokimia (EIS) untuk melihat hambatan yang dihasilkan dan berpengaruh terhadap konduktivitas listrik dari katode. Hasil karakterisasi memperlihatkan bahwa penambahan Mo dengan jumlah tertentu dan karbon yang merata dapat meningkatkan konduktivitas listrik dari katode NMC 811. Uji Cyclic Voltamettry (CV) menunjukkan puncak oksidasi reduksi yang lebih dari 1 dan mengindikasikan pengotor.

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Synthesis using a combination of solution combustion synthesis (SCS) and solid state methods has been carried out and tested to obtain a lithium ion battery cathode LiNi0,8Mn0,1Co0,1-xMoxO2/C with precursors LiNO3, Ni(NO)3.6H2O, Mn(NO3)2.4H2O, Co(NO3)2.6H2O, (NH4)6Mo7O24, and CH4N2O as fuel by being dissolved in distilled water and stirred using a hot plate magnetic stirrer at room temperature. The solution was heated at a temperature of 100 oC for 1 hour to 200oC for 2 hours to form a dark brown paste. Further heating was carried out in a muffle furnace at a temperature of 500oC for 2 hours, and calcination at a temperature of 900oC for 3 hours. Super-p carbon black was added as addition as much as 0.5 wt% and mixed with NMC 811 powder using agathe mortar for 1 hour and calcined at 300oC for 3 hours. The synthesized black powder was analyzed by electron microscopy (SEM) to see morphology. SEM results showed that the synthesized sample had a size in the range of 0.1-1.55 m. X-ray diffraction test (XRD) to see the crystallinity and showed that there was a shift of the 2θ peak to the right due to the influence of the metal oxide formed. Electrochemical analysis was carried out with electrochemical impedance (EIS) to see the resulting resistance and its effect on the electrical conductivity of the cathode. The characterization results showed that the addition of a certain amount of Mo and an even distribution of carbon could increase the electrical conductivity of the NMC 811 cathode. Cyclic Voltamettry (CV) test showed an oxidation-reduction peak that was more than 1 and indicated an impurity."

"Asam oleat atau asam Z-Δ9-oktadekanoat diketahui sebagai salah satu asam lemak yang memiliki toksisitas yang rendah dan memiliki aktivitas antimikroba, sehingga dikembangkan penelitian untuk mendapatkan senyawa turunan dari asam oleat dan mengetahui bioaktivitasnya. Pada penelitian ini, dilakukan sintesis turunan asam amino dari senyawa asam oleat dengan reaksi esterifikasi dan amidasi, lalu dikarakterisasi dengan KLT dan FTIR. Asam oleat diesterifikasi dengan katalis basa, kemudian diamidasi dengan asam amino glisin dan asam amino fenilalanin. Setelahnya, dilakukan uji pendahuluan BSLT dan uji antimikroba dengan metode difusi cakram. Dari hasil penelitian didapatkan % kematian dari konjugat asam oleat, glisin oleat, dan fenilalanin oleat. Asam Oleat dengan konsentrasi 16,6 ppm memiliki % kematian paling tinggi yaitu 35%. Adapun hasil uji antimikroba konjugat asam oleat, glisin oleat, dan fenilalanin oleat tidak memiliki aktivitas antimikroba terhadap bakteri kulit gram positif yaitu Staphylococcus aureus dan bakteri kulit gram negatif yaitu Escherichia coli.

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Oleic acid or Z-Δ9-octadecanoic acid is known as a fatty acid that has low toxicity and antimicrobial activity, so research was developed to obtain compounds derived from oleic acid and determine its bioactivity. In this research, the synthesis of amino acid derivatives from oleic acid compounds by esterification and amidation reactions was carried out, then characterized by TLC and FTIR. Oleic acid is esterified with a base catalyst, then amides with the amino acid glycine and the amino acid phenylalanine. After that, a preliminary BSLT test and an antimicrobial test using the disc diffusion method were carried out. From the results of the study obtained % of deaths from conjugates of oleic acid, glycine oleic, and phenylalanine oleate. Oleic acid with a concentration of 16.6 ppm had the highest % mortality, namely 35%. The results of the antimicrobial conjugate test of oleic acid, glycine oleic, and phenylalanine oleate did not have antimicrobial activity against gram-positive skin bacteria, namely Staphylococcus aureus and gram-negative skin bacteria, Escherichia coli."