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Abstrak :
Kompleks Paladium terutama banyak digunakan sebagai katalis dalam bidang industri dan obat antikanker Penelitian ini bertujuan untuk mempelajari sintesis, karakteristik spektra, dan kegunaan senyawaan kompleks Paladium(II) dengan 2,2'-bipiridin (DPY) dan 2,9~dimeti|-1,10-fenantrolin (fen) sebagai katalis pada aikoholisis urea. Senyawaan kompleks Pa|adium(II) dengan bpy dan fen masing-masing disintesis dengan perbandingan 1:1 dan 1:2 Serta dikarakterisasi menggunakan spektrofotometer uitraungu-tampak dan inframerah. Selain itu, senyawaan kompleks dengan perbandingan 1:1 diaplikasikan sebagai katalisator pada alkohoiisis urea. Kompleks Pd(bpy)CI2 berwama kuning tua, sedangkan kompleks [Pd(bpy)2]Cl2 berwama kuning. Kompleks [Pd(fen)(H;0)2](C|04)2 berwarna coklat muda, sedangkan kompleks [Pd(fen)2](C|04)2 berwarna putih bening. Puncak serapan IE--HC* untuk ligan bpy terkompleks bergeser ke arah panjang gelombang Iebih besar daripada bpy bebas, sedangkan untuk Iigan fen terkompleks bergeser ke arah panjang gelombang Iebih kecil dibandingkan fen bebas. Serapan transisi d->d untuk kompleks Pd(II) dengan bpy terjadi pada panjang gelombang sekitar 373 nm dan dua puncak serapan transisi tersebut untuk kompleks Pd(II) dengan fen terjadi pada panjang gelombang antara 301 sampai 337 nm. Spektra senyawa kompleks Pd(II) dengan bpy pada frekuensi antara 199 sampai 245 om" memperlihatkan dua puncak serapan baru yang menandakan adanya ikatan antara ion Pd(II) dengan ligan akibat pengompleksan. Spektra inframerah ligan bpy dan fen terkompleks pada frekuensi 400-4000 cm°? menunjukkan adanya pergeseran vibrasi ulur C=N dan C=C, serta vibrasi tekuk C-H ke arah frekuensi yang Iebih besar daripada bpy bebas. Kompleks Pd(ll) dengan ligan dalam perbandingan 1:1 dapat dimanfaatkan sebagai katalis dalam alkoholisis urea. Tempat koordinasi yang diisi oleh ligan lemah dapat digantikan oleh urea. Urea yang terikat sebagai ligan akan bereaksi dengan metanol membentuk ester karbamat melaiui metanolisis. Ester karbamat ini akan terdisosiasi secara cepat dan kompleks kembali ke bentuk semula.

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Abstract
Complexes of Palladium are widely used as catalyst in industry and anticancer drugs. The aims of this research were to study of synthesis, spectra characteristic and preliminary test of complexes of Palladium(II) with 2,2'-bipyridine(bpy) and 2,9-dimethyl-1,10-phenanthroline (fan) for catalyst in urea alcoholysis. Complexes of Pd(ll) with bpy and fen were synthesized with 1:1 and 1:2 ratio, respectively and there were characterized with UV-We and IR spectrophotometers. Complex compounds with 1:1 ratio were applicated as catalyst in urea alcoholysis complex of [Pd(bpy)Cl2] is yellow, while complex of [Pd(bpy)2]Cl2 is dark yellow. Complex of [Pd(fen)(H2O)2](Cl04)2 is brown, while complex of [Pd(fen)2](CIO4)2 is white-Peaks of absorption cause of 1:->1r* transition for bpy complex is shifted to higher wavelength than of free bpy, while for fen complex are shifted to lower wavelength than free fen. Absorptions d->d transition for complex of Pd(II) with bpy occurs about 373 nm and two peaks of those transition for complex of Pd(ll) with fen occurs between 301 until 337 nm. Spectra of complexes of Pd(ll) with bpy between 199 until 245 cm" showed two peaks. infrared spectra of bpy and fen complexed in frequency 400-4000 cm" showed a shift C=N and C=C vibrations and C-H vibration to higher frequency than free ligand. Complexes of Pd(Il) with 1:1 ratio can used as catalyst in alooholysis urea. Coordination of weak ligand can changed with urea. Urea is bonded as ligan will react with metanol foml ester carbamate via metanolysis Ester carbamate will dissociated fast and complex revert to first form.

Abstrak :
Elektroda Boron-Doped Diamond termodifikasi core-shell nanopartikel AuPd telah berhasil dipreparasi dengan cara perendaman BDD terminasi N dalam koloid nanopartikel AuPd. Lapisan shell Pd NP terbentuk pada core nanpartikel Au dari hasil reduksi larutan HAuCl4 dengan variasi penambahan H2PdCl4 1,0 mM dan asam askorbat. Spektrum UV-Vis dari nanopartikel Au menunjukkan panjang gelombang maksimum pada ? = 523 nm yang diikuti dengan penurunan absorbansi AuPd NP seiring pembentukan nanopartikel palladium. Karakterisasi nanopartikel menggunakan Transmission Electron Microscopy TEM menunjukkan bahwa core-shell AuPd NP memiliki bentuk flower shape dengan diameter Au NP sebesar 14,26 nm dan ketebalan Pd NP masing-masing 6,91 nm dan 4,05 nm. AuPd NP yang dideposisi ke permukaan elektroda BDD-N dikarakterisasi menggunakan Scanning Electron Microscopy Energy Dispersive X-Ray SEM-EDX dan X-Ray Photoelectron Spectroscopy XPS. Penentuan kadar oksigen dilakukan menggunakan teknik siklik voltammetri dalam larutan buffer fosfat PBS dengan variasi lamanya waktu aerasi oksigen yang diukur menggunakan DO meter. Hasil pengukuran menujukkan bahwa kemampuan pemisahan sinyal arus terhadap background pada elektroda BDDN-AuPdNP 1 S/B = 2,82 lebih baik dibandingkan BDDN-AuNP S/B = 2,59 dan BDDN-AuPdNP 2 S/B = 1,12 . Pembentukan Pd NP pada permukaan Au NP mempengaruhi sensitifitas pada elektroda sehingga modifikasi elektroda BDD-N dengan nanopartikel AuPd diharapkan dapat menghasilkan elektroda yang lebih sensitif untuk pengukuran oksigen dan dapat dikembangkan selanjutnya untuk penentuan BOD dalam air. ......Core shell nanoparticle Au Pd modified Boron Doped Diamond electrode has been succesfully prepared by immersion of BDD terminating N in Au Pd colloid nanoparticles. The Pd shell layer was formed on Au nanoparticle cores from the reduction of HAuCl4 solution with variations of 1.0 mM H2PdCl4 volume addition and ascorbic acid. UV Vis spectra of Au nanoparticles showed the maximum wavelength was obtained at 523 nm which followed by the decreasing of absorbance of AuPdNP as the formation of Pd shell. Characterization of nanoparticles using Transmission Electron Microscopy TEM shows that the AuPd Np core shell has a flower like shape with 14.26 nm of AuNP core diameter and PdNP shell thickness of 6.91 nm and 4.05 nm, respectively. The AuPd NPs were deposited on BDD N surface and were characterized using Scanning Electron Microscopy Energy Dispersive X Ray SEM EDX and X Ray Photoelectron Spectroscopy XPS. Determination of oxygen level was carried out using cyclic voltammetry in phosphate buffer solution PBS at various oxygen aeration time where its concentration was measured using DO meter. The results show that BDDN AuPdNP 1 had a better current to background signaling capability S B 2.82 than BDDN AuNP S B 2.59 and BDDN AuPdNP 2 S B 1.12 . It is belived that the formation of Pd shell on the surface of Au NP affects the sensitivity of the electrode. As the result, modification of BDD N electrodes with Au Pd nanoparticles are expected to produce more sensitive electrodes for oxygen measurements which can be further developed for Determination of BOD in the water.

Abstrak :
Effects of additing 1 percent (w/o) palladium (Pd) on the thermal behavior of a lathe cut type high copper amalgam (13 w/o copper) were studied. The identical alloys, with and without 1% Pd were fabricated. X-ray diffraction studies of the amalgams revealed the elimination of the y2-phase by Pd addition. DSC thermogram of non-Pd containing amalgam indicated the existence of two y1-phasesone with the transition temperature (endothermic peak) at 88°C and the other at 109°C. The thermogram data of the Pd containing amalgam showed an endothermic peak at 110,7°C. The transition temperature of the n phase of the palladium containing amalgam is 4,9°C lower than the transition temperature of the n phase of the non Pd containing amalgam. This result indicates that the n phase of the Pd containing amalgam includes more of Tin (Sn) than the non-Pd containing amalgam. The thermogravimetri diagram showed that the phase decomposition occured at about 390°C for the non-Pd containing amalgam and at about 410°C for the Pd containing amalgam. It's concluded that the addition of 1% Pd into a lathe cut type of high copper amalgam (13%) could eliminate the formation of y2 phase as well as an unstable y1 phase, promoting strong mercury bonding to silver.

Abstrak :
Industri tekstil merupakan penyumbang terbesar limbah zat warna ke dalam air, contohnya zat warna metilen biru yang bersifat racun, karsinogenik, dan tidak dapat terurai secara alami. Salah satu teknik mengurangi kadar metilen biru adalah melalui degradasi secara fotokatalitik dengan menggunakan semikonduktor. CuBi2O4 merupakan semikonduktor tipe-p dengan celah pita yang sempit (1,5 – 1,8 eV) dapat digunakan sebagai fotokatalis untuk degradasi metilen biru karena memiliki respon cahaya tampak. Penambahan logam mulia Paladium (Pd) dapat meningkatkan kinerja aktivitas fotokatalitik CuBi2O4 karena dapat menekan rekombinasi pasangan e− dan h+. Penelitian ini, telah berhasil mensintesis CuBi2O4 melalui metode solvotermal, dan mensintesis nanokomposit Pd/CuBi2O4 dengan variasi perbandingan rasio mol Pd:CuBi2O4 (1:1, 1:2, dan 2:1) melalui metode presipitasi dan reduksi. CuBi2O4 dan Pd/CuBi2O4 hasil sintesis telah dibuktikan melalui karakterisasi dengan XRD, TEM, FTIR, dan UV-Vis DRS. Uji sifat katalis dilakukan pada larutan Metilen Biru dengan variasi penambahan massa katalis sebesar 5 mg, 10 mg, dan 15 mg, serta variasi kondisi (fotolisis dan adsorpsi). Persentase degradasi metilen biru paling optimum adalah pada katalis Pd/CuBi2O4 (2:1) 10 mg, yaitu sebesar 82,63% dengan laju degradasi 8,9 × 10-3 min-1. ......Textile industry is the largest contributor of colorant waste into water, for instance, the toxic, carcinogenic, and non-biodegradable dye methylene blue. One of the techniques to reduce the concentration of methylene blue is through photocatalytic degradation using a semiconductor. CuBi2O4 is a p-type semiconductor with a narrow bandgap (1.5 - 1.8 eV) that can be utilized as a photocatalyst for methylene blue degradation due to its visible light response. The addition of the noble metal Palladium (Pd) can enhance the photocatalytic activity of CuBi2O4 by suppressing the recombination of electron-hole pairs (e− dan h+). In this research, CuBi2O4 has been successfully synthesized through the solvothermal method, and Pd/CuBi2O4 nanocomposites have been synthesized with various ratios of Pd:CuBi2O4 (1:1, 1:2, and 2:1) using the precipitation and reduction method. CuBi2O4 and Pd/CuBi2O4 synthesized products have been characterized using XRD, TEM, FTIR, and UV-Vis DRS. The catalytic properties test was performed on Methylene Blue solutions with varying catalyst masses of 5 mg, 10 mg, and 15 mg, as well as different conditions (photolysis and adsorption). The optimum percentage of methylene blue degradation was observed with the catalyst Pd/CuBi2O4 (2:1) 10 mg, which was 82.63%, with a degradation rate of 8,9 × 10-3 min-1.

Abstrak :
The author has developed novel methodologies for highly efficient construction of functionalized heterocycles by palladium-catalyzed domino/cascade cyclization of allenes and related compounds containing appropriate nucleophilic group(s). Based on these methodologies, enantioselective total syntheses of bioactive natural products, pachastrissamine (26% overall yield in seven steps), lysergic acid (4.0% overall yield in fifteen steps), lysergol (3.6% overall yield in fifteen steps) and isolysergol (8.2% overall yield in eleven steps) have been achieved.