[Co(μ-ox)(Hpmtz)] - A New CoII Zig-Zag Chain Complex with the In Situ Generated Oxalate Bridging and Hpmtz Chelating Ligands (Hpmtz = 5-pyrimidyltetrazole) Exhibiting Spin-Canted Antiferromagnetism

2011 ◽  
Vol 2012 (2) ◽  
pp. 203-207 ◽  
Author(s):  
A. Rodríguez-Diéguez ◽  
José Manuel Seco ◽  
E. Colacio
Keyword(s):  
Chain Complex ◽  
Chelating Ligands ◽  
Oxalate Bridging

scholarly journals Lanthanoid Complexes Supported by Retro-Claisen Condensation Products of β-Triketonates

2018 ◽  
Author(s):  
Laura Abad Galán ◽  
Alexandre N. Sobolev ◽  
Eli Zysman-Colman ◽  
Mark Ogden ◽  
Massimiliano Massi
Keyword(s):  
Chelating Ligands ◽  
X Ray Diffraction ◽  
Reaction Conditions ◽  
Claisen Condensation ◽  
X Ray ◽  
Condensation Products ◽  
Complexation Reactions ◽  
The Impact ◽  
Low Solubility

<i>β</i>-Triketonates have been recently used as chelating ligands for lanthanoid ions, presenting unique structures varying from polynuclear assemblies to polymers. In an effort to overcome low solubility of the complexes of tribenzoylmethane, four <i>β</i>-triketones with higher lipophilicity were synthesised. Complexation reactions were performed for each of these molecules using different alkaline bases in alcoholic media. X-ray diffraction studies suggested that the ligands were undergoing decomposition under the reaction conditions. This is proposed to be caused by <i>in situ</i>retro-Claisen condensation reactions, consistent with two examples that have been reported previously. The lability of the lanthanoid cations in the presence of a varying set of potential ligands gave rise to structures where one, two, or three of the molecules involved in the retro-Claisen condensationreaction were linked to the lanthanoid centres. These results, along with measurements of ligand decomposition in the presence of base alone, suggest that using solvents of lower polarity will mimimise the impact of the retro-Claisen condensation in these complexes. <br>

scholarly journals Lanthanoid Complexes Supported by Retro-Claisen Condensation Products of β-Triketonates

2018 ◽  
Author(s):  
Laura Abad Galán ◽  
Alexandre N. Sobolev ◽  
Eli Zysman-Colman ◽  
Mark Ogden ◽  
Massimiliano Massi
Keyword(s):  
Chelating Ligands ◽  
X Ray Diffraction ◽  
Reaction Conditions ◽  
Claisen Condensation ◽  
X Ray ◽  
Condensation Products ◽  
Complexation Reactions ◽  
The Impact ◽  
Low Solubility

<i>β</i>-Triketonates have been recently used as chelating ligands for lanthanoid ions, presenting unique structures varying from polynuclear assemblies to polymers. In an effort to overcome low solubility of the complexes of tribenzoylmethane, four <i>β</i>-triketones with higher lipophilicity were synthesised. Complexation reactions were performed for each of these molecules using different alkaline bases in alcoholic media. X-ray diffraction studies suggested that the ligands were undergoing decomposition under the reaction conditions. This is proposed to be caused by <i>in situ</i>retro-Claisen condensation reactions, consistent with two examples that have been reported previously. The lability of the lanthanoid cations in the presence of a varying set of potential ligands gave rise to structures where one, two, or three of the molecules involved in the retro-Claisen condensationreaction were linked to the lanthanoid centres. These results, along with measurements of ligand decomposition in the presence of base alone, suggest that using solvents of lower polarity will mimimise the impact of the retro-Claisen condensation in these complexes. <br>

scholarly journals Lanthanoid Complexes Supported by Retro-Claisen Condensation Products of β-Triketonates

2018 ◽  
Author(s):  
Laura Abad Galán ◽  
Alexandre N. Sobolev ◽  
Eli Zysman-Colman ◽  
Mark Ogden ◽  
Massimiliano Massi
Keyword(s):  
Condensation Reaction ◽  
Chelating Ligands ◽  
X Ray Diffraction ◽  
Claisen Condensation ◽  
X Ray ◽  
Condensation Products ◽  
The Stability ◽  
Decomposition Pathway ◽  
Complexation Reactions

<i>β</i>-Triketonates have been recently used as chelating ligands for lanthanoid ions presenting unique structures varying from assemblies to polymers. Despite their novel complexation behaviour little is known about the stability of these molecules. Indeed, two examples of possible <i>in situ</i>retro-Claisen condensation reactions have been reported previously. To better understand this possible decomposition pathway, four new <i>β</i>-triketones were synthesised. Complexation reactions were performed for each of these molecules using different alkaline bases in alcoholic media, aiming to isolate the potentially varying ligands present in solution. The X-ray diffraction studies revealed the formation of structures where one, two, or three of the molecules involved in the retro-Claisen condensation reaction were linked to the lanthanoid centres.

scholarly journals Lanthanoid Complexes Supported by Retro-Claisen Condensation Products of β-Triketonates

2018 ◽  
Author(s):  
Laura Abad Galán ◽  
Alexandre N. Sobolev ◽  
Eli Zysman-Colman ◽  
Mark Ogden ◽  
Massimiliano Massi
Keyword(s):  
Chelating Ligands ◽  
X Ray Diffraction ◽  
Reaction Conditions ◽  
Claisen Condensation ◽  
X Ray ◽  
Condensation Products ◽  
Complexation Reactions ◽  
The Impact ◽  
Low Solubility

<i>β</i>-Triketonates have been recently used as chelating ligands for lanthanoid ions, presenting unique structures varying from polynuclear assemblies to polymers. In an effort to overcome low solubility of the complexes of tribenzoylmethane, four <i>β</i>-triketones with higher lipophilicity were synthesised. Complexation reactions were performed for each of these molecules using different alkaline bases in alcoholic media. X-ray diffraction studies suggested that the ligands were undergoing decomposition under the reaction conditions. This is proposed to be caused by <i>in situ</i>retro-Claisen condensation reactions, consistent with two examples that have been reported previously. The lability of the lanthanoid cations in the presence of a varying set of potential ligands gave rise to structures where one, two, or three of the molecules involved in the retro-Claisen condensationreaction were linked to the lanthanoid centres. These results, along with measurements of ligand decomposition in the presence of base alone, suggest that using solvents of lower polarity will mimimise the impact of the retro-Claisen condensation in these complexes. <br>

In situ hybridisation mapping of genomic clones for five human respiratory chain complex I genes

1997 ◽  
Vol 78 (1) ◽  
pp. 21-24 ◽  
Author(s):  
D.R. Dunbar ◽  
Y. Shibasaki ◽  
L. Dobbie ◽  
B. Andersson ◽  
A.J. Brookes
Keyword(s):  
Respiratory Chain ◽  
Complex I ◽  
In Situ Hybridisation ◽  
Chain Complex ◽  
Respiratory Chain Complex ◽  
Genomic Clones

Unconventional Lanthanoid Complexes Supported by Retro-Claisen Condensation Products of β-Triketonates

2018 ◽  
Author(s):  
Laura Abad Galán ◽  
Alexandre N. Sobolev ◽  
Eli Zysman-Colman ◽  
Mark Ogden ◽  
Massimiliano Massi
Keyword(s):  
Condensation Reaction ◽  
Chelating Ligands ◽  
X Ray Diffraction ◽  
Claisen Condensation ◽  
X Ray ◽  
Condensation Products ◽  
The Stability ◽  
Decomposition Pathway ◽  
Complexation Reactions

<i>β</i>-Triketonates have been recently used as chelating ligands for lanthanoid ions presenting unique structures varying from assemblies to polymers. Despite their novel complexation behaviour little is known about the stability of these molecules. Indeed, two examples of possible <i>in situ</i>retro-Claisen condensation reactions have been reported previously. To better understand this possible decomposition pathway, four new <i>β</i>-triketones were synthesised. Complexation reactions were performed for each of these molecules using different alkaline bases in alcoholic media, aiming to isolate the potentially varying ligands present in solution. The X-ray diffraction studies revealed the formation of structures where one, two, or three of the molecules involved in the retro-Claisen condensation reaction were linked to the lanthanoid centres.

scholarly journals Adsorption of heavy metal with modified eggshell membrane and the in situ synthesis of Cu–Ag/modified eggshell membrane composites

2018 ◽  
Vol 5 (9) ◽  
pp. 180532 ◽  
Author(s):  
Yaqing Xin ◽  
Caihong Li ◽  
Jianing Liu ◽  
Jinrong Liu ◽  
Yuchen Liu ◽  
...  
Keyword(s):  
Heavy Metals ◽  
Catalytic Performance ◽  
Eggshell Membrane ◽  
Chelating Ligands ◽  
Ag Nps ◽  
Key Factor ◽  
Coordination Effect ◽  
Effective Sorbent ◽  
Excellent Catalytic Performance

The objectives of this study were to remove heavy metals from wastewater through the biosorption method with modified biomass as an effective sorbent and to prepare metal/biomass composites with the same modified biomass as a direct template. Eggshell membrane (ESM) was selected and modified to adsorb heavy metals. Adsorption of metal ions on the modified ESM (MESM) might be attributed to electrostatic interaction, ion exchange and coordination effect with chelating ligands containing N and S on the surface of the MESM. The pH of the solution was a key factor affecting the adsorption. The Cu–Ag/MESM composites with uniform Cu–Ag NPs were prepared with MESM as matrices, and with Cu 2+ and Ag + adsorbed as metal sources. The Cu–Ag/MESM showed excellent catalytic performance in the reduction of 4-nitrophenol to 4-aminophenol in the aqueous phase. Because of the high stability of the Cu–Ag NPs supported on the macro-dimension supporter, Cu–Ag/MESM can be easily separated after the catalytic reaction and recycled.

Rendez vous with Saturn's rings

1984 ◽  
Vol 75 ◽  
pp. 743-759 ◽  
Author(s):  
Kerry T. Nock
Keyword(s):  
Solar Energy ◽  
Electric Propulsion ◽  
Power Source ◽  
Propulsion System ◽  
Low Thrust ◽  
Ring Plane ◽  
The Earth ◽  
Total Impulse ◽  
Saturn's Rings

ABSTRACTA mission to rendezvous with the rings of Saturn is studied with regard to science rationale and instrumentation and engineering feasibility and design. Future detailedin situexploration of the rings of Saturn will require spacecraft systems with enormous propulsive capability. NASA is currently studying the critical technologies for just such a system, called Nuclear Electric Propulsion (NEP). Electric propulsion is the only technology which can effectively provide the required total impulse for this demanding mission. Furthermore, the power source must be nuclear because the solar energy reaching Saturn is only 1% of that at the Earth. An important aspect of this mission is the ability of the low thrust propulsion system to continuously boost the spacecraft above the ring plane as it spirals in toward Saturn, thus enabling scientific measurements of ring particles from only a few kilometers.

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