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Bent Dinuclear Platinum(II) Halo-Bridged Carbonyl Complexes  [PDF]
Daniela Belli Dell'Amico,Luca Labella,Fabio Marchetti
Molecules , 2011, DOI: 10.3390/molecules16076082
Abstract: Crystals of trans-Pt2(μ-X)2X2(CO)2 (X = Br, I) have been grown and their molecular and crystalline structures have been solved by X-ray diffraction methods. In both cases the dinuclear molecules are bent, with a bending angle of 164.6° and 156.5° for the bromide and the iodide, respectively. While the structure of the bromo-derivative is reported here for the first time, a modification of trans-Pt2(μ-I)2I2(CO)2 with planar centrosymmetric molecules is known. This appears to be a rare case of a platinum(II) halo-bridged derivative structurally characterized in both bent and planar forms.
Inorganic-organic hybrids constructed of bis(undecatungstogermanate)lanthanates polyoxoanions and oxalate-bridged dinuclear copper complexes and their magnetic properties
Ping Sun,FengJi Ma,ShuXia Liu
Chinese Science Bulletin , 2011, DOI: 10.1007/s11434-011-4488-x
Abstract: A series of inorganic-organic hybrids K2Na m H9 m [{Ln(GeW11O39)2}{Cu2(bpy)2(μ-ox)}]·nH2O (bpy = 2,2-bipyridine and ox = oxalate; Ln = La, Nd, Sm, Eu, Gd; n = 19, 17, 22, 20, 19; m = 4, 4, 4, 9, 2) were isolated after reacting in a potassium acetate buffer. X-ray structural analyses show that compounds 1–5 are isomorphic and consist of [Ln(GeW11O39)2]13 polyoxoanion building blocks and oxalate-bridged dinuclear copper metalorganic complex with a 1D chain structure. The 1D chain further connects into the 3D framework by π-π interactions with neighboring bpy groups. The magnetic susceptibility data indicate that antiferromagnetic coupling between the neighboring Cu2+ ions in the structure and the rare earth ions affects magnetic property of the structure.
Hydroformylation of Synthetic Naphtha Catalyzed by a Dinuclear gem-Dithiolato-Bridged Rhodium(I) Complex
gemAlvaro J. Pardey, José D. Suárez, Marisol C. Ortega, Clementina Longo, Jesùs J. Pérez-TorrenteLuis A. Orooxooxo
The Open Catalysis Journal , 2008, DOI: 10.2174/1876214X01003010044]
Abstract: This work focuses on the use of a gem-dithiolato-bridged rhodium(I) [Rh2(μ-S2CBn2)(cod)2] complex (cod = 1,5-cyclooctadiene, Bn2CS2- = 1,3-diphenyl-2,2-dithiolatopropane) dissolved in toluene in the presence of monodentate phosphite P-donor ligand (P(OPh)3) under carbon monoxide/hydrogen (1:1, syngas) atmosphere as an effective catalyst for hydroformylation of some olefins (oxo-reactions). The capability of this system to catalyze the hydroformylation of hex-1-ene, cyclohexene, 2,3-dimethyl-but-1-ene and 2-methyl-pent-2-ene and their quaternary mixture (synthetic naphtha) has been demonstrated. This innovative method to perform the in situ hydroformylation of the olefins present in naphthas to oxygenated products would be a promissory work for a future industrial catalytic process applicable to gasoline improving based on oxo-reactions. An important observation is that variation of CO/H2 pressure (6.8 – 34.0 atm), temperature (60 – 80 °C), reaction time (2 – 10 h), rhodium concentration ((1.0 – 1.8)x10-3 mol/L) affect hydroformylation reaction rates. Optimal conversion to oxygenated products were achieved under [Rh] = 1.8 x10-2 mol/L, P(CO/H2) = 34 atm (CO/H2 = 1:1) at 80 °C for 10 h.
Synthesis, characterization and X-ray structural studies of four copper (II) complexes containing dinuclear paddle wheel structures
Samson Jegan Jenniefer, Packianathan Thomas Muthiah
Chemistry Central Journal , 2013, DOI: 10.1186/1752-153x-7-35
Abstract: Four compounds, each containing dinuclear Copper (II) units (with the most robust, frequently occurring paddle wheel structures) were synthesized and characterised by single crystal X-ray diffraction and by IR spectroscopy. The compounds 1 & 2 have the general formula Cu2(RCOO) 4(L)2 [(for (1) RCOO= 4-Chloro Benzoate , L= Isopropanol ; for 2 RCOO= Benzoate , L= 2-Amino-4,6-dimethyl pyrimidine )] while 3 & 4 have the general formula, Cu2(RCOO) 4(S)2 Cu2(RCOO) 4(L)2 [RCOO=5-Chloro-thiophene-2-carboxylate L= 2-Amino-4,6-dimethyl pyrimidine, for 3 S= ethanol ; for 4 S= methanol ]. A wide range of hydrogen bonds (of the O-H...O, N-H...O and N-H...N type) and pi-pi stacking interactions are present in the crystal structures.All compounds contain the dinuclear units, in which two Cu(II) ions are bridged by four syn,syn-eta1:eta1:mu carboxylates, showing a paddle-wheel cage type with a distorted octahedral geometry. The compounds 1 & 2 contain a single dimeric unit while 3 & 4 contain two dimeric units. The structures 3 and 4 are very interesting co-crystals of two paddle wheel molecules. Also it is interesting to note that the compounds 3 & 4 are isostructural with similar cell parameters. Both the compounds 3 & 4 differ in the solvent molecule coordinated to copper in one of the dimeric units. In all the four compounds, each of the copper dimers has an inversion centre. Every copper has a distorted octahedral centre, formed by four oxygen atoms (from different carboxylate) in the equatorial sites. The two axial positions are occupied by copper and the corresponding ligand.
Fusion Probability in Dinuclear System  [PDF]
Juhee Hong
Physics , 2015,
Abstract: Fusion can be described by the time evolution of a dinuclear system with two degrees of freedom, the relative motion and transfer of nucleons. In the presence of the coupling between two collective modes, we solve the Fokker-Planck equation in a locally harmonic approximation. The potential of a dinuclear system has the quasifission barrier and the inner fusion barrier, and the escape rates can be calculated by the Kramers' model. To estimate the fusion probability, we calculate the quasifission rate and the fusion rate. We investigate the coupling effects on the fusion probability and the cross section of evaporation residue.
Dinuclear concept - cluster model of fusion  [PDF]
G. G. Adamian,N. V. Antonenko,E. A. Cherepanov,A. K. Nasirov,W. Scheid,V. V. Volkov
Physics , 1999,
Abstract: The synthesis of superheavy elements is analysed within the dinuclear system concept of compound nucleus formation. The perspectives for using radioactive beams in complete fusion reactions are discussed.
Influenza - flu  [PDF]
Val?i? Miroslav A.,Radoji?i? Sonja
Veterinarski Glasnik , 2010, DOI: 10.2298/vetgl1002109v
Abstract: In epidemiology or in epizootiology, there are some infectious diseases that have potential for significant reduction of the susceptible species population. Over the past few decades, epidemiologists were concentrated on diseases that were 'modern' and made front-page news in tabloids. One should recall diseases like bovine spongiform encephalopathy, SARS and AIDS syndromes. However, we should always be aware of the most dangerous diseases such as our old friend, influenza, or simply, flu. In the past decade, we heard about 'bird' or 'swine' influenza. It is the same disease for different animal species as well as for man. Influenza owes its characteristics to specific virus biology as well as to the epidemiology-epizootiology characteristics of the susceptible species. Antigenic changes that took place thanks to reassortment mechanisms of the viral gene segments cause the onset of the new antigenic combinations of the hemaglutinin and neuraminidase molecules. As a result, new H and/or N antigenic formulas appear for the first time in totally susceptible animal and human populations. That means that in such circumstances, no person in the world is immune to the virus. In that case, such a virus can cause a pandemic with disastrous consequences since influenza is a disease with significant mortality, especially in some segments of the human (as well as animal) population. Birds and swine are virus reservoirs, but these species are at the same time live test tubes in which the virus resides, changes and adapts itself not only to the original species but to other species as well. That means that there is no 'bird' or 'swine' flu. Influenza is an infection of several important animal species as well as man that have potential not only for the reduction of the population size but, in case of the human population, for influencing social and economic life. .
dmf应用研究  [PDF]
食品科学 , 1995,
Abstract: ?dmf应用研究王盛良,韩承平南京市卫生防疫站210003引言近年来,人们对dmf(富马酸_jp酯)进行不了少研究。islam(]984)[’‘报道,将dmf用一厂天米饼中,其防霉效果在同等添加量的情况一下大大优于两酸钙。mora(1983)[’j指出...
TAF Preventive Medicine Bulletin , 2005,
Abstract: Avian influenza (bird flu) is a contagious disease of animals caused by influenza A viruses. These flu viruses occur naturally among birds. Actually, humans are not infected by bird flu viruses.. However, during an outbreak of bird flu among poultry, there is a possible risk to people who have contact infect birds or surface that have been contaminated with excreations from infected birds. Symptoms of bird flu in humans have ranged from typical flu-like symptoms to eye infections, pneumonia, severe respiratory diseases and other severe and life-threatening complications. In such situation, people should avoid contact with infected birds or contaminated surface, and should be careful when handling and cooking poultry.
Katarzyna Łuczyńska-Szymczak,Wojciech Starosta,Janusz Leciejewicz
Acta Crystallographica Section E , 2012, DOI: 10.1107/s1600536812023240
Abstract: The asymmetric unit of the polymeric title compound, [Mg3(C9H3O6)2(C3H7NO)4]n, contains three MgII ions bridged by carboxylate O atoms from two fully deprotonated benzene-1,3,5-tricarboxylate (BTC) trianions and four metal-coordinated dimethylformamide (DMF) molecules. One MgII ion is octahedrally coordinated by six carboxylate O atoms. The other two cations are each octahedrally coordinated by four carboxylate O atoms and two O atoms donated by two DMF molecules: in one, the DMF molecules are cis and in the other they are trans. The three MgII octahedra form clusters, which are bridged by the BTC trianions, generating a three-dimensional structure.
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