Synthesis and electrochemical characterization of bimetallic ruthenium complexes with the bridging eta2(s,s)-1,3-butadiyne-1,4-diyl ligand

The bis(ruthenium)alkyne complex [cis-{RuCl (bpy)2(mu-CºC-)}]2 (1) was obtained by treatment of 1 equiv of either 1,4-bis(trimethylsilyl)-1,3-butadiyne or bis(trimetylsilyl)acetylene with 2 equiv of cis-[RuCl2(bpy)2].2H2O, NaF and NaBF4 salts in methanol/CH2Cl2 mixture (10/1) in 52% and 35% yields, respectively. ¹H, 13C{H} NMR and principally electrochemical analyses confirmed that the same product was obtained from the two reactions. Cyclic voltammetric analyses of (1) from 0 to 1.20 V displays two one-electron quasi-reversible oxidation peaks attributed to the Ru(II)/Ru(III) couple. The redox processes are separated by 520 mV, indicating a significant electronic communication between the two metallic centers.O complexo [cis-{RuCl(bpy)2(mi-CºC-)}] 2 (1) foi obtido pelo tratamento de 1 equive de 1,4-bis(trimetilsilil)-1,3-butadiino ou bis(trimetilsilil)acetileno com 2 equiv do complexo cis-[RuCl2(bpy)2].2H2O, NaF e NaBF4na mistura de solventes metanol/CH2Cl2 (10/1) com rendimentos de 52% e 35%, respectivamente. Análises de RMN de ¹H, 13C{H} e principalmente eletroquímica, confirmaram que o mesmo produto foi obtido dos dois métodos. Análise de (1) através de voltametria cíclica, no intervalo de potencial de 0 a 1,20 V mostrou dois picos de oxidação quasi-reversíveis referentes ao par redox Ru(II)/Ru(III). Os dois processos redox são separados por 520 V, indicando comunicação eletrônica significante entre os dois centros metálicos252256Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP

Uji Perbedaan Kualitas Pelayanan Proses Pembelajaran Sebelum dan Sesudah Pelaksanaan Program Hibah Kompetisi (PHK) A2 Jurusan Matematika FMIPA Universitas Sriwijaya

Beberapa upaya peningkatan kualitas pelayanan proses pembelajaran yang telah dilakukan di Jurusan Matematika adalah perbaikan berbagai fasilitas dan peningkatan pengetahuan/keahlian dosen melalui Program Hibah Kompetisi (PHK) A2 mulai tahun 2006 sampai tahun 2008. Penelitian ini bertujuan untuk mengevaluasi kualitas palayanan proses pembelajaran sebelum dan sesudah PHK A2, berdasarkan penilaian mahasiswa terhadap lima dimensi kualitas pelayanan. Metode yang digunakan adalah survei dengan teknik Simple Random Sampling terhadap mahasiswa aktif di jurusan. Teknik analisis yang digunakan adalah deskriptif dan inferensi dengan Uji Peringkat Bertanda Wilcoxon. Hasil penelitian menunjukkan bahwa kualitas pelayanan proses pembelajaran sesudah pelaksanaan PHK A2 cenderung lebih baik dibandingkan dengan sebelum PHK A2. Hal ini diperlihatkan dengan menurunnya persentase mahasiswa yang menyatakan sangat tidak puas dan tidak puas serta terjadi peningkatan persentase mahasiswa yang menyatakan cukup puas, puas dan sangat puas. Selain itu, hasil pengujian hipotesis menyimpulkan adanya perbedaan yang signifikan dari kualitas pelayanan proses pembelajaran sebelum dengan sesudah pelaksanaan PHK A2. Dengan kata lain, pelaksanaan PHK A2 memberikan pengaruh nyata terhadap peningkatan kualitas pelayanan proses pembelajaran di Jurusan Matematika Fakultas MIPA Universitas Sriwijaya

Electronic structure and effects of dynamical electron correlation in ferromagnetic bcc-Fe, fcc-Ni and antiferromagnetic NiO

LDA+DMFT method in the framework of the iterative perturbation theory (IPT) with full LDA Hamiltonian without mapping onto the effective Wannier orbitals. We then apply this LDA+DMFT method to ferromagnetic bcc-Fe and fcc-Ni as a test of transition metal, and to antiferromagnetic NiO as an example of transition metal oxide. In Fe and Ni, the width of occupied 3d bands is narrower than those in LDA and Ni 6eV satellite appears. In NiO, the resultant electronic structure is of charge-transfer insulator type and the band gap is 4.3eV. These results are in good agreement with the experimental XPS. The configuration mixing and dynamical correlation effects play a crucial role in these results

Analisis Dampak Penurunan Muka Tanah Terhadap Tingkat Ekonomi Menggunakan Kombinasi Metode Dinsar Dan Sig (Studi Kasus : Kota Semarang)

Semarang city is the capital city of Central Java Province which is geographically located in 110o16\u2720”- 110o30\u2729” E and 60o55\u2734”- 70o7\u2704” N, and it is about 391,2 km2. Semarang is a city in a coastal area which was formed alluvial sediment. It has it\u27s characteristic process where the land is still through the consolidation process. It causes a land subsidence in those area. Moreover, explorations of land water and the burden of the surface of the land also contribute the land subsidence in Semarang.The purpose of this research is to find out the land subsidence in Semarang by using DInSAR method. DInSAR is a side scan radar technology which uses a phase information, amplitudo, and the wave length to get topography and deformation data. The data which was used in the process is ALOS PALSAR level 1.0 images with the acquisition data in June 2007 (20070608), July 2008 (20080726), and September 2008 (20080910). DInSAR method which was used to process the data was two-pass interferometry with Shuttle Radar Topography (SRTM) as Digital Elevation Model (DEM) to give the topography reference. The DInSAR Process was processed with SARScape software and use a combination of Geographic Information Systems (GIS) for the analysis of economic losses.The result of this research showed the land subsidence in Semarang has got the maximum velocity rate is about 9.059±1.89 cm/year in 20070608-20080910 and it\u27s about 1.979±1.24 cm/year in 20080726-20080910. The area which got the worst impact of the land subsidence is around 69.58 km2 and showed the results in economic losses to the effects of subsidence from the infrastucture sector amounted to idr. 70.983 billion, public facilities idr.16.472 billion, agriculture idr. 1.563 billion and idr. 57.238 billion for settlement

Hydrothermal System and Seismic Activity of Hakone Volcano

The structure of the Hakone hydrothermal system and geochemistry of thermal waters are described. The subsurface temperature map and the zonal distribution of thermal waters strongly suggest that thermal energy of the Hakone system is essentially supplied by dense volcanic steam rich in sodium chloride coming up through the volcanic conduit, from which subsurface streams of sodium chloride waters are derived. The seismic activity of Hakone mostly takes place at relatively shallow depths in the central part of the caldera. The chemical and physical properties of the dense steam are examined assuming that the phase transformation of water to steam is the major cause for volcanic earthquakes. The Cl-SO{sub 4} chemistry permits estimation of sodium chloride content of 0.5 to 1% in original dense steam responsible for sodium chloride waters. Thanks to the work of Sourirajan and Kennedy (1962) temperature pressure condition of volcanic dense steam at depths of 1 to 2 km below sea-level is estimated to be about 385 C and 230 bars, dissolving 0.5 to 1% of sodium chloride in steam. Below the depth of 4 km, earthquakes seldom occur, the hydrothermal system is saturated with solid sodium chloride, resulting in lowered vapor pressure. This implies that the permeation of meteoric water to the volcanic steam system mostly takes place at a depth less than 4 km. The analogy of hot eyes (centers of geothermal fields) and cold eyelids (surroundings of low temperature area) is emphasized for better understanding of hydrothermal systems