bluuebunny/crossref_metadata_2025 huggingface dataset:
Synthesis, Spectroscopic Study and Crystal Structure Determination by X‐ray Powder Diffractometry of [CdCl2(TzTn)] [TzTn=2‐(3,4‐dichlorophenyl)imino‐N‐(2‐thiazolin‐2‐yl)tetrahydro‐1,3‐thiazine]
Authors: Lozano‐Vila A. M. , Cumbrera F. L. , Luna‐Giles F. , Ortiz A. L. , Bernalte‐García A.
Published: August 2007

The cadmium(II) complex, dichloro[2‐(3,4‐dichlorophenyl)imino‐κN‐N‐(2‐thiazolin‐κN‐2‐yl)tetrahydro‐1,3‐thiazin]cadmium(II), was synthesized in the form of fine powder with small crystals unsuitable for structure determination by X‐ray single‐crystal diffractometry, and was therefore characterized by X‐ray powder diffractometry. To that end, the molecular structure was first analyzed using various instrumental techniques including elemental analysis, FAB‐mass spectroscopy, and infrared spectroscopy, and then optimized via molecular modeling with a semi‐empirical quantum‐chemistry model. From the optimized molecule, the crystal structure wasresolved within the methodological framework of the direct‐space methods using a ‘Monte‐Carlo/parallel tempering’ search algorithm, and then refined using the Rietveld method. It was found that the title compound crystallizes in the triclinic system, with the space group $\rm P{\bar 1}$, two C13H13Cl4CdN3S2 molecules in the asymmetric unit, and the following unit cell dimensions: a = 13.558(4) Å, b = 13.579(7) Å, c = 10.117(4) Å, α = 91.07(3)°, β = 95.44(3)°, and γ = 93.03(3)°. It was also found that the environment around the cadmium(II) ion may be described as distorted tetrahedral, with the metallic atom coordinated to two chlorine atoms [Cd(A)‐Cl(1A) = 2.44(3) Å; Cd(A)‐Cl(2A) = 2.44(3) Å; Cd(B)‐Cl(1B) = 2.45(3) Å; Cd(B)‐Cl(2B) = 2.45(3) Å], one imino nitrogen atom [Cd(A)‐N(3A) = 2.37(10) Å; Cd(B)‐N(3B) = 2.37(9) Å], and one thiazoline nitrogen atom [Cd(A)‐N(1A) = 2.33(8) Å; Cd(B)‐N(1B) = 2.33(10) Å].
Two‐dimensional Holodirected Lead(II) Coordination Polymer, [Pb(μ‐bpp)(μ‐SCN)2]n (bpp = 1,3‐di(4‐pyridyl)propane)
Authors: Taheri Syavash , Mojidov Ajdar , Morsali Ali
Published: August 2007

A lead(II) complex with 1,3‐di(4‐pyridyl)propane (bpp) and thiocyanate ligands, [Pb(μ‐bpp)(μ‐SCN)2]n (1), has been synthesized and characterized by CHN elemental analysis, IR‐, 1H‐ and 13C NMR spectroscopy. The single crystal X‐ray data of compound 1 show that the complex is two‐dimensional coordination polymer and the Pb atom has less‐common six–coordinate holodirected arrangement.
Ferrocenophanes with Interannular Nitrogen‐Aluminum Bridges – Synthesis and Structure
Authors: Wrackmeyer Bernd , Klimkina Elena V. , Milius Wolfgang
Published: August 2007

The reaction of 1,1′‐bis(trimethylsilylamino)ferrocene (1) with trimethyl‐ or triethylaluminum proceeds by elimination of methane or ethane, respectively, to novel ferrocenophanes 2a,b containing an N2Al2 bridge. Addition of pyridine to 2 affords the pyridine adducts of 1,3‐diaza‐2‐alkylalumina‐[3]ferrocenophanes (4a,b) and of AlR3. The [3]ferrocenophanes 4 can be converted into 2 by addition of AlR3. The solution‐state structure of the new compounds follows from a consistent set of NMR spectroscopic data (1H, 13C, 15N, 27Al and 29Si NMR) measured at variable temperature. The molecular structures of the 2b and 4a,b were determined by single crystal X‐ray analyses.
Incidence of Microwave Hydrothermal Treatments on the Crystallinity Properties of Hydrotalcite‐like Compounds
Authors: Benito P. , Guinea I. , Herrero M. , Labajos F. M. , Rives V.
Published: August 2007

Layered double hydroxides with different cations in the layers, MgAl, ZnAl and CoAl, have been prepared. The solids were obtained by the coprecipitation method and then they were submitted to the microwave radiation in order to improve the crystallinity and minimize the particle size of the solids. The samples were characterized by element chemical analysis, powder X‐ray diffraction, FT‐IR spectroscopy, particle size distribution, and transmission electron microscopy.
Synthesis, Crystal Structure and Magnetic Properties of 4,4′‐ Bipyridine Bridged Dinuclear Iron(III) Complex containing N,N′‐Ethylene‐Bis(salicylideneiminato)
Authors: Feng Xun , Wang Jian‐Ge , Xie Cheng‐Zhi , Ma Ning
Published: August 2007

A new bis‐Schiff base iron(III) dinuclear complex [(Fe2(salen)2bipy(NCS)2] (salen = N,N′‐ethylene‐bis(salicylideneiminato), 4,4′‐bipy = 4,4′‐bipyridine) has been prepared by one–pot template condensation and characterized by X‐ray diffraction and magnetochemistry. The structure consists of two pseudo‐octahedral high‐spin iron(III) units linked by 4,4′‐bipy. The iron(III) ion has distorted octahedral coordination with a N2O4 donor set. The symmetry moiety of N, N′ bis‐(salicylideneamino)ethanato ligand coordinates to the iron(III) ion in equatorial plane in a tetradentate mode including phenol oxygen and imine nitrogen atom, the axial positions are occupied by the nitrogen atoms from isothiocyanato group and the 4,4′‐bipy ligand. Variable–temperature magnetic measurements in the range 2‐300 K of the complex indicate the presence of weak antiferromagnetic exchange between the two nearest Fe3+ ions with J = –0.38 cm−1.
Syntheses, Structures and Luminescent Properties of Three Silver(I) Complexes with a Novel Imidazole‐Containing Schiff Base Ligand
Authors: Lu Xi‐Hong , Huang Yong‐Qing , Kong Ling‐Yan , Okamura Taka‐aki , Sun Wei‐Yin , Ueyama Norikazu
Published: August 2007

Three novel silver(I) complexes [Ag2(L)2](NO3)2 (1), [Ag2(L)2](BF4)2 (2) and [Ag2(L)2](CF3CO2)2 (3) have been synthesized by reactions of Schiff base ligand 1‐(imidazol‐4‐yl)‐5‐(imidazol‐1‐yl)‐2‐azapent‐1‐ene (L) with the corresponding metal salts and characterized by single crystal X‐ray diffraction analysis. Complex 1 has one dimensional (1D) chain structure, while complex 2 has two‐dimensional (2D) network structure, in which two unique 1D chains with different shapes are linked together via Ag···Ag interactions. Complex 3 features a discrete M2L2 molecular ring. The results show that the nature of the counterions has remarkable impact on the structure of the supramolecular structures. The photoluminescent properties of the synthesized complexes were studied in the solid state at room temperature. In addition, complex 1 was further investigated by electrospray mass spectrometry.
The Influence of the Methyl Substituents at C2 Carbon of Thiosemicarbazones {R1R2C2=N3‐N2H‐C1(=S)N1H2} on Bonding and Structures of Copper(I) Complexes
Authors: Lobana Tarlok S. , Khanna Sonia , Butcher Ray J.
Published: August 2007

Reaction of copper(I) halides with acetone thiosemicarbazone (Hactsc) and acetaldehyde thiosemicarbazone (Hmtsc) in CH3CN in the presence of PPh3 has formed dimeric complexes of type, [Cu2(μ‐X)2(η1‐S‐Htsc)2(Ph3P)2] (Htsc: X; Hmtsc, Br, 1; I, 2; Hactsc, I, 3; Cl, 5), and a monomer, [CuBr((η1‐S‐Hactsc)(Ph3P)2 (4). The complexes have been characterized using analytical data, spectroscopy and X‐ray crystallography (1–4). The presence of methyl substituents at C2 carbon of thiosemicarbazone seems to alter inter‐ and intra‐molecular hydrogen bonding. Intermolecular and intramolecular interactions by amino and imino hydrogen atoms respectively with bridging halogen atom shorten X–Cu–X bond angle, and open up Cu–X–Cu bond angle, resulting in longer Cu···Cu separation (3.50–3.61Å) in complexes 1–3.
Synthesis and Structure of Half‐Sandwich Zincocenes
Authors: Resa Irene , Álvarez Eleuterio , Carmona Ernesto
Published: August 2007

Half‐sandwich zinc complexes (η5‐C5Me5)ZnR have been prepared for R= Me,2; Et,3; Mes,4and Ph,5, by the conproportionation reaction of Zn(C5Me5)2and the corresponding ZnR2reagent. The new compounds have been fully characterized by spectroscopy and in the cases of2and4by X‐ray crystallography. Since the reaction of Zn(C5Me5)2and ZnEt2yields3, together with the known dizincocene Zn2(η5‐C5Me5)2, the rearrangements of the related zincocenes ZnCp2′ and ZnEt2were investigated, with the result that only the half‐sandwich (η5‐Cp′)ZnEt derivatives (Cp′= C5Me4SiMe3(6); C5Me4CMe3(7) and C5Me4H (8)) were produced.
Electrochemical Synthesis and Characterization of Zinc(II) and Cadmium(II) Complexes of Dianionic Tetradentate Schiff Base Ligand
Authors: Rodríguez Laura , Labisbal Elena , Sousa‐Pedrares Antonio , Romero Jaime , García Vázquez José‐Arturo , Sousa Antonio
Published: August 2007

The electrochemical oxidation of anodic metal (zinc or cadmium) in acetonitrile solution of the potentially chelating Schiff base N,N‐(dithiodiethylenebis(aminylydenemethylydene)bis(1,2‐phenylene)ditosylamide (H2L) afforded stable complexes of empirical formula [ML]. The crystal and molecular structures of [ZnL]·CH3CN (1) and [CdL] (2) have been determined by X‐ray diffraction. In both complexes the metal atom is in a distorted tetrahedral environment with the Schiff base acting as a tetradentate N4 donor. Spectroscopic data for the complexes (IR, ES MS and 1H NMR spectra) are discussed and related to the structural information.
Synthesis, Crystal Structures and Properties of [Cu(L1)2(py)2(H2O)](H2O)[HL1 = N‐(5‐ethyl‐[1,3,4]–thiadiazole‐2‐yl)‐toluenesulfonamidate] and [Cu(L2)2(py)2(H2O)] [HL2 = N‐(5‐ethyl‐[1,3,4]–thiadiazole‐2‐yl)‐benzenesulfonamidate]
Authors: Hangan Adriana , Borras Joaquin , Liu‐Gonzalez Malva , Oprean Luminita
Published: August 2007

A series of new N‐sulfonamidate ligands and their cooper(II) complexes, [Cu(N‐(5‐ethyl‐[1,3,4]‐thiadiazole‐2‐yl)‐toluenesulfonamidate)2(py)2(H2O)](H2O) (1) and [Cu(N‐(5‐ethyl‐[1,3,4]‐thiadiazole‐2‐yl)‐benzenesulfonamidate)2(py)2(H2O)] (2) have been synthesized and characterized. The X‐ray crystal structures of the complexes 1 and 2 have been determined. In the both two complexes, the Cu2+ ion is five‐coordinated, forming a CuN4O chromophore. The ligands act as monodentate, coordinating the metal ion through a single Nthiadiazole atom. The molecules from the reaction medium (pyridine and water) also participate to the coordination of Cu2+ ion as monodentate ligands. Both two complexes have a slightly distorted square pyramidal geometry. The chemical properties of the complexes have been studied by FT‐IR, electronic and EPR spectroscopic methods.
Metal Complexes with a New Ethyl Acetate Pendant‐Armed Macrocyclic Ligand – Crystal Structures of [MnL](ClO4)2 and [NiL](ClO4)2·CH3CN
Authors: López‐Deber M. , Bastida de la Calle R. , Macías A. , Pérez‐Lourido P. , Rodríguez A. , Valencia Matarranz L.
Published: August 2007

A new ligand, L, bearing two ethyl acetate pendant groups has been synthesized by reaction of the precursor ligand LA with ethylbromoacetate. The coordination capability towards transition [Mn2+, Ni2+], post‐transitional [Zn2+ and Cd2+] and Pb2+ ions has been investigated starting from the hydrated perchlorate salts of the metals. The new ligand L and the metal complexes obtained were characterized by elemental analysis, FAB MS, conductivity measurements, magnetic studies, IR, UV‐vis and 1H and 13C NMR spectroscopy. Furthermore, the crystal structures of the complexes [MnL](ClO4)2 and [NiL](ClO4)2·CH3CN were determined.
Synthesis and Characterization of Cobalt Complexes of Heterocyclic Bidentate Ligands (N,X), X= S, Se
Authors: Valenzuela E. , Sousa‐Pedrares A. , Durán‐Carril M. L. , García‐Vázquez J. A. , Romero J. , Sousa A.
Published: August 2007

The synthesis and structural characterization of a series of homoleptic cobalt complexes of general formula [Co(R‐pyX)3] is reported, where X = S, Se; R = H, 3‐CF3 and 5‐CF3. The compounds were synthesized by electrochemical oxidation of the metal in a cell containing an acetonitrile solution of the corresponding ligand. When 2,2′‐bipyridine (bipy) or 1,10‐phenanthroline (phen) were added to the electrolytic cell, mixed cobalt(II) compounds [Co(R‐pyX)2L] (L = bipy, phen) were also isolated. All of the complexes obtained have been characterized by microanalysis, vibrational and electronic spectroscopy, FAB mass spectrometry and, in the case of diamagnetic compounds that were sufficiently soluble, by 1H and 13C NMR spectroscopy. Crystals of [Co(3‐CF3‐pyS)3] and [Co(5‐CF3‐pyS)3] were obtained and studied by X‐ray diffraction. The crystal structures consist of monomeric molecules with the metal atom in an octahedral environment and the ligands in a meridional disposition.
Comparative Study of Reactivity of Copper(II) Salts with N,N′‐Dipyridyl Ligands. Structural Diversity and Magnetic Properties
Authors: Delgado S. , Medina M. E. , Pastor C.J. , Jiménez‐Aparicio R. , Priego J. L.
Published: August 2007

The coordination chemistry of 1,2‐bis(2‐pyridyl)butadiyne (dpb) 2,5‐bis(2‐pyridylethynyl)thiophene (dpet) (rigid ligands) and 4,4′‐dipyridyldisulfide (4‐dpds) (flexible ligand) with Cu(tfac)2 (tfac= trifluoroacetylacetonate) and Cu(BF4)·xH2O have been investigated in order to test the influence of different anions on the overall structure. Three of the resulting metal‐organic assemblies have been determined. These crystal structures have shown that the geometry and coordinating properties of the corresponding anions together with the positional orientation of the nitrogen atoms in the ligands are essential in determining the final structures of the assemblies. So, reactions with Cu(tfac)2 lead to dimeric compounds [Cu2(tfac)4(L)] for L = dpb 1 and dpet 2 and one‐dimensional polymer [Cu(tfac)2(4‐dpds)]n (3) for 4‐dpds ligand. On the other hand analogous reactions with Cu(BF4)·xH2O afforded the copper(II) complexes [Cu(dpb)(BF4)2·(CH3OH)1.5]n (4) and [Cu(4‐dpds)2/(BF4)2(MeOH)(CH2Cl2)]n (6) for dpb and 4‐dpds ligands as well as the copper(I) compound [Cu(dpet)2]n(BF4)·CH2Cl2 (5) for dpet ligand. In addition to this, magnetic properties have been studied.
Synthesis and Characterization of Triphenylphosphinesilver(I) Sulfanylcarboxylates of the Type [HQ][Ag(PPh3)(L)] [HQ] = Diisopropylammonium
Authors: Barreiro Elena , Casas José S. , Couce María D. , Sánchez Agustín , Sordo José , Varela José M. , Vázquez‐López Ezequiel M.
Published: August 2007

Compounds of the type [HQ][Ag(PPh3)(L)] {H2L = H2xspa: x = p (3‐phenyl‐), Clp [3‐(2‐chlorophenyl)‐], ‐o‐mp [(3‐(2‐methoxyphenyl)‐], ‐p‐mp [(3‐(4‐methoxyphenyl)‐], ‐o‐hp [3‐(2‐hydroxyphenyl)‐], ‐p‐hp [3‐(4‐hydroxyphenyl)‐], diBr‐o‐hp [3‐(3,5‐dibromo‐2‐hydroxyphenyl)‐], f [3‐(2‐furyl)‐], t [3‐(2‐thienyl)‐], ‐o‐py 3‐(2‐pyridyl); spa = 2‐sulfanylpropenoato and 2‐cyclopentylidene‐2‐sulfanylacetic acid (H2cpa)} were synthesized and characterized by IR, Raman and NMR (1H, 13C and 31P) spectroscopy and by FAB mass spectrometry. The structure of [HQ][Ag(PPh3)(pspa)] (1) shows that the crystal contains hydrogen‐bonded diisopropylammonium cations and [Ag(PPh3)(pspa)]22− anions, which have a central Ag2S2 planar ring, to give extended chains.
Cycloplatination of Thiosemicarbazones Derived from Furane. Crystal and Molecular Structure of [{Pt[(OC4H2)C(Me)=NN=C(S)NHEt]}2{μ‐Ph2P(CH2)2PPh2}]
Authors: Adrio Luis , Antelo José M. , Ortigueira Juan M. , Lata Darío , Pereira Teresa , López‐Torres Margarita , Vila José M.
Published: August 2007

Treatment of thiosemicarbazones (OC4H3)C(Me)=NN(H)C(=S)NHR (R: Me, a; Et, b) with [cis‐PtMe2(cod)] afforded the tetranuclear compounds [Pt{(OC4H2)C(Me)=NN=C(S)NHR}]4 (R: Me, 1a; Et, 1b). The reaction of 1a and 1b with triphenylphosphine in 1:4 molar ratio gave rise to the mononuclear compounds [Pt{(OC4H2)C(Me)=NN=C(S)NHR}(PPh3)] (2a, 2b). Treatment of 1a and 1b with large‐bite diphosphines Ph2P(CH2)nPPh2 (n = 2, dppe; n = 3, dppp; n = 4, dppb) afforded the dinuclear compounds ‐[{Pt[(OC4H2)C(Me)=NN=C(S)NHR]}2{μ‐Ph2P(CH2)nPPh2}], (3a–5a, 3b–5b), with the diphosphine in a bridging mode. Similar reactions with the short‐bite diphosphines Ph2PCH2PPh2 (dppm) and Ph2PC(=CH2)PPh2 (vdpp) yielded the mononuclear compounds [Pt{(OC4H2)C(Me)=NN=C(S)NHR}‐(Ph2PCH2PPh2‐P)] (6a, 6b) and [Pt{(OC4H2)C(Me)=NN=C(S)NHR}(Ph2P‐C(=CH2)PPh2‐P)] (7a, 7b) with the diphosphine in a monodentate coordination. Treatment of 1a and 1b with [W(CO)5(Ph2CH2PPh2)] gave the novel heterodinuclear species [{Pt[(OC4H2)C(Me)=NN=C(S)NHR]}{W(CO)5(Ph2CH2PPh2‐P)}] (8a, 8b), which could also be synthesized by reaction of 6a and 6b with [W(CO)5(THF)]. 1H, 31P‐{1H} and 13C‐{1H} NMR and IR data are given. The crystal structure of compound 3b has been determined by X‐ray crystallography.
Copper(II) and Nickel(II) Complexes of two Nitrogen‐Functionalized N‐Salicylidene Carbonic Acid Hydrazides: Molecular and Supramolecular Architectures
Authors: Roth Arne , Buchholz Axel , Gärtner Martin , Malassa Astrid , Görls Helmar , Vaughan Gavin , Plass Winfried
Published: August 2007

Copper(II) and nickel(II) complexes with the new Schiff‐base ligands N‐salicylidene‐3‐(2‐pyridyl)‐propionic acid hydrazide (H2salhypyp) and the newly synthesized N‐Salicylidene‐3‐(1‐benzylimidazol‐2‐yl)‐propionic acid hydrazide (H2salhyimp) have been synthesized and structurally characterized. The crystal structure analysis of the metal complexes reveals two fundamentally different structural motifs. Cationic di‐μ‐phenolate‐bridged dimers are observed for the complexes with the H2salhypyp ligand, [{Cu(H2salhypyp)(MeOH)(ClO4)}2](ClO4)2 (1) and [{Ni(H2salhypyp)Cl(MeOH)}2]Cl2(MeOH)2 (2), whereas neutral dimeric units aggregated via the side chain nitrogen donors are observed for the complexes with the H2salhyimp ligand, [{Ni(salhyimp)}2](H2O)4 (4) and [{Cu(salhyimp)}2](MeOH)4 (3). The formation of either motif depends on the charge of the ligand species and consequently on the pH‐value of the reaction solution. For the complexes 1 and 2 extensive hydrogen‐bonding networks are observed which involve the perchlorate (N–H···O–Cl) and chloride anions (N–H···Cl), respectively. The M2O2 core unit of complexes 1 and 2 facilitates the formation of intramolecular M–(Me)O–H···X–M hydrogen‐bonding interactions $\rm (X = ClO^{-}_{4}, Cl^{-})$. The copper complex 3 exhibits an unusual one‐dimensional coordination polymer which is linked through the axial coordination of phenolate oxygen atoms of adjacent dimeric units. Complex 4 exhibits a layered structure with each layer composed of hydrophobic π‐stacks of the dimeric complex units which are interlaced by hydrogen‐bonded chains of water molecules. The supramolecular structures of 3 and 4 are governed by π‐π‐stacking interactions. For 4 additional CH/π interactions are found within and between individual sheets of the layered structure.
Synthesis, Structure and Chemical Bonding of RE4RuMg (RE = La–Nd, Sm, Gd–Ho)
Authors: Tuncel Selcan , Chevalier Bernard , Matar Samir F. , Pöttgen Rainer
Published: August 2007

The rare earth metal rich compounds RE4RuMg (RE = La–Nd, Sm, Gd–Ho) were obtained by induction‐melting of the elements in sealed tantalum tubes in a water‐cooled sample chamber of a high‐frequency furnace. The RE4RuMg compounds were studied by powder X‐ray diffraction: Gd4RhIn type, $F {\rm {\bar 4}}{\rm 3}m$, a = 1433.6(2) pm for La4RuMg, a = 1408.1(2) pm for Ce4RuMg, a = 1405.9(1) pm for Pr4RuMg, a = 1399.5(3) pm for Nd4RuMg, a = 1384.7(1) pm for Sm4RuMg, a = 1381.4(2) pm for Gd4RuMg, a = 1371.1(2) pm for Tb4RuMg, a = 1367.2(2) pm for Dy4RuMg, and a = 1361.4(5) pm for Ho4RuMg. The structures of RE4RuMg with RE = La, Pr, Nd, and Sm were refined from single crystal diffractometer data. The RE4RuMg structures consist of a three‐dimensional network of edge‐ and corner‐sharing RuRE6 trigonal prisms. In contrast to the isotypic series RE4CoMg and RE4RhMg, the ruthenium atoms displace from the centers of the prisms. The voids within the three‐dimensional network are filled by regular Mg4 tetrahedra at a Mg–Mg distance of 316 pm in La4RuMg. The magnesium atoms have icosahedral coordination by three magnesium and nine rare earth metal atoms. The samarium based crystal revealed a small homogeneity range Sm3−xRu1+yMg1+x−y leading to the refined composition Sm3.92Ru1.16Mg0.92. Chemical bonding in La4RuMg was studied in comparison with La4CoMg. The La1–Mg bonding is found to be dominating among the La–Mg interactions in both systems. Differences in chemical bonding due to a reduced valence electron concentration and different La2–Ru versus La3–Ru distances within RuLa23La33 prisms are traced out.
Isolation of a Manganese Complex of a Tridentate Azo‐aromatic Ligand from an Unusual Mn2(CO)10 Promoted Simultaneous Reductive Azo Cleavage and Aromatic Ring Amination Reactions
Authors: Chatterjee Sudipta , Sanyal Anasuya , Hung Chen‐Hsiung , Goswami Sreebrata
Published: August 2007

The reaction of Mn2(CO)10 with pap [pap = 2‐(phenylazo) pyridine, L1] in boiling n‐octane affords a violet complex, [Mn(L2)2] (1, HL2 NH4C5N=NC6H4N(H)C6H5). This reaction exemplifies an unusual transformation wherein the anionic tridentate ligand (L2)− is formed by the fusion of phenyl imide fragment, originated from the splitting of the –N=N‐ function of L1, to pendant phenyl ring of the coordinated azo ligand. X‐ray structure of the manganese complex is reported.
Primary and P‐Alkylated o‐Phosphanylphenols: Synthesis by Reduction and Reductive Alkylation of Diethyl Arylphosphonates and Screening in Ethylene Polymerization
Authors: Heinicke Joachim , Musina Elvira , Peulecke Normen , Karasik Andrey A. , Kindermann Markus K. , Dobrynin Alexey B. , Litvinov Igor A.
Published: August 2007

Various diethyl aryl phosphates 1a‐e and the 2‐bromo derivatives 2a,d were ortholithiated to access the corresponding rearranged O‐lithiated 2‐hydroxy‐benzene‐phosphonates 3a‐e. These compounds or the isolated free hydroxyl derivatives 4 were reduced by LiAlH4 in the absence and presence of alkyl halides to give primary 2‐phosphanylphenols 5 and P‐alkylated derivatives 6‐11. The reductive alkylation allows a one‐step access to P‐secondary or P‐tertiary 2‐phosphanylphenols from 3 or 4. The selectivity depends on the substitution pattern. Screening of 2‐phosphanylphenol / Ni(COD)2 solutions in ethylene batch polymerizations revealed higher conversion and polymer chain lengths by catalysts with O‐basic secondary and even primary than with 2‐diphenylphosphanylphenolate ligands.
Chloro‐2‐(diphenylphosphino)benzaldehyde 4‐phenylsemicarbazonato‐P, N, N′)methoxooxorhenium(V) – a Semicarbazone Complex with an Unusual Coordination Mode
Authors: Barandov Ali , Abram Ulrich
Published: August 2007

(NBu4)[ReOCl4] reacts with 2‐(diphenylphosphino)benzaldehyde 4‐phenylsemicarbazone (HL1) in methanol under formation of the red rhenium(V) complex [ReO(Cl)(OMe)(L1)]. The semicarbazonato ligand is singly deprotonated and coordinates meridionally via the phosphorus atom and two nitrogen atoms. This unusual coordination mode of a semicarbazone is confirmed by IR and NMR spectroscopy and by the solid state structure of the product.
The First Crystal Structures of Mercury(II) Complexes of Tetra‐amides (L1 and L2) and Tetramethylamides (L3 and L4) of EDTA and PDTA. Formation of Distorted Octahedral and Distorted Capped Octahedral Mercury(II) Complexes and of a Trinuclear Complex containing HgCl2‐bridged [Hg(L3)Cl]+ Moieties
Authors: Krot Krystyna , Llamas‐Saiz Antonio L. , Vembu Nagarajan , Nolan Kevin B.
Published: August 2007

The first crystal structures of HgII complexes of EDTA and PDTA tetra‐amides are reported. Reaction of EDTA and PDTA tetra‐amides (L1 and L2) and tetramethylamides (L3 and L4) with HgCl2 in water/ethanol/acetone produced complexes of formula [Hg(L1)Cl][HgCl4]0.5·0.5H2O, (1), [Hg(L2)Cl]2[HgCl4]·6H2O, (2), [Hg3(L3)2Cl4][HgCl3]2·2H2O, (3), [Hg(L3)Cl]2(PF6)2·5H2O, (4), and [Hg(L4)Cl]2[HgCl3]2·1.5H2O, (5), in which the denticity of the tetraamide ligand is 6 in complexes 1 ‐ 4 but 5 in complex 5 giving distorted capped octahedral 7‐coordinate complexes and distorted octahedral 6‐coordinate complexes, respectively. Complex 3 contains a trinuclear cation resulting from HgCl2‐bridging of two [HgL3(Cl)]+moieties. The X‐ray crystal structures of the complexes reveal the existence of supramolecular aggregates resulting from infinite 3D frameworks of H‐bonds.
New Neutral Metal Complexes from the 4‐N‐Phenylthiosemicarbazone‐2‐pyridinecarboxaldehyde Ligand – 113Cd and 207Pb NMR Studies
Authors: Bermejo Manuel R. , González‐Noya Ana M. , Martínez‐Calvo Miguel , Pedrido Rosa , Maneiro Marcelino , Fernández M. Isabel , Gómez‐Fórneas Esther
Published: August 2007

The metal complexes studied in this report derive from the ligand 4‐N‐phenylthiosemicarbazone‐2‐pyridinecarboxaldehyde, abbreviated HL, and the transition and post‐transition metals manganese, iron, cobalt, nickel, copper, silver, zinc, cadmium and lead.

The new complexes were obtained by an electrochemical procedure and were found to be of the form ML2·nH2O (n = 1−4) for divalent metals and ML·nH2O (n = 0, 4) for Cu and Ag metals. These complexes have been wholly characterized by elemental analysis, mass spectrometry, infrared spectroscopy, magnetic measurements and molar conductivities. NMR studies in solution (1H, 113Cd and 207Pb NMR) were also performed. [MnL2]·CHCl3 (1), [ZnL2]·CH3CN (2) and [CdL2]·CH3CN (3) could be crystallographically characterized and their crystal structures show the metal atoms in a distorted octahedral environment.
Neutral Mono‐ and Cationic Bis‐Aziridine d6‐Metal Complexes of the Type [(π‐arene)M(Az)Cl2] and [(π‐arene)M(Az)2Cl]Cl (π‐arene/M = η6‐C6Me6/Ru; η5‐C5Me5/Rh, Ir)
Authors: Bobka Roman , Roedel J. Nicolas , Neumann Bernd , Krinninger Christoph , Mayer Peter , Wunderlich Stefan , Penger Alexander , Lorenz Ingo‐Peter
Published: August 2007

The synthesis of neutral mono‐ and cationic bis‐aziridine complexes of ruthenium(II), rhodium(III) and iridium(III) are described. The dimeric complexes [MCl2L]2 (M = RuII, L = C6Me6; M = RhIII/IrIII, L = C5Me5) (1‐3) react with a series of aziridines (Az = C2H4NH, C2H3MeNH, C2H2Me2NH, C2H3EtNH, C2H3PhNH) (a‐e) in a 1:2 or 1:5 molar ratio to give the neutral mono‐aziridine complexes [MCl2L(Az)] (4e‐6e) or cationic bis‐aziridine complexes [MClL(Az)2]Cl (7a‐9d), respectively. After purification, all of the complexes were fully characterized and the IR, MS, 1H and 13C NMR spectra are reported and discussed. The single crystal structure analysis revealed a distorted octahedral structure for all complexes.
Evolution of Ceramics with Medical Applications
Authors: Salinas Antonio J. , Vallet‐Regí María
Published: August 2007

Bioceramics are those ceramics designed to be implanted into the human body. In the last fifty years these materials experienced an enormous evolution. Initially, the objective was bio–inertness, that is a minimum interaction with the living organism. These bioceramics are nowadays called first generation. The second generation bioceramics started to be widely investigated in the 1980s with the goal of a positive interaction with living tissues. This group collects bioactive and resorbable bioceramics. At the beginning of the 21stCentury it is clear that the medical paradigm of tissue substitution must be replaced with tissue regeneration. Bioceramics must be supplemented with cells and biologically active molecules. The investigation in third generation bioceramics has just started. In this article, a description of the main second generation ceramics and new advanced ceramics currently under our investigation aimed to be used as scaffolds and templates in third generation biomaterials is presented.
A Double Chain Metal‐organic Framework Constructed by Tetrameric Nickel(II) Units and 1,3,5‐Benzenetricarboxylic Trianions
Authors: Xie Linhua , Liu Shuxia , Cao Ruige , Gao Chaoying , Cao Jianfang
Published: August 2007

Hydrothermal reaction of nickel sulfate, 1,3,5‐benzenetricarboxylic acid and deprotonation agent ethylenediamine yields a metal‐organic framework [Ni4(μ3‐OH)2(H2O)10(BTC)2]·H2O, which consists of double chains constructed from tetrameric nickel(II) units and 1,3,5‐benzenetricarboxylic trianions. Hydrogen bonds and π‐π stacking interactions among these chains result in the three‐dimensional structure of the compound. Magnetic study reveals there are ferromagnetic interactions among the Ni2+ ions of each Ni4 units in the compound.
Reaction of [Fe2(CO)6{μ‐COLi(THF)3}2] with Me3SiCl – Crystal Structure of [Fe3(CO)9(μ3‐COSiMe3){μ3‐COLi(THF)3}]
Authors: Petz Wolfgang , Neumüller Bernhard
Published: August 2007

From the reaction of [Fe2(CO)6{μ‐COLi(THF)3}2] (1) with two equivalents of Me3SiCl in THF solution the trinuclear cluster [Fe3(CO)9(μ3‐COSiMe3){μ3‐COLi(THF)3}] (2) could be isolated, in which the COLi(THF)3 ligand bridges two iron atoms and is bonded to the third Fe atom in a semibridging manner. 2 is characterized by an X‐ray analysis; it crystallizes in the monoclinic space group P21/n with a = 1471.6(2), b = 1169.6(1), c = 2043.8(2) pm, β = 94.05(1), Z = 4.
Crystal Structures and EPR Spectra of Cu2+‐Doped Magnesium(II) and Cadmium(II) Methoxyacetates
Authors: Hitchman Michael A. , Hockless David C. R. , Skelton Brian W. , Stratemeier Horst , White Allan H.
Published: August 2007

Magnesium methoxyacetate crystallizes from aqueous solution as a dihydrate, isomorphous with its nickel(II) and copper(II) counterparts, the six‐coordinate metal atoms being disposed on crystallographic inversion centres in space group P21/n. The cadmium complex is anhydrous, the six‐coordinate metal atoms being linked into a two‐dimensional polymer parallel to the ab plane in space group P21/c by bridging coordination through carboxylate oxygen atoms. The powder EPR spectra of traces of Cu2+ doped into the magnesium(II) and cadium(II) compounds show slight temperature dependences, with the higher two g‐values converging as the temperature is raised from ∼77 K to 290 K. This is analysed in terms of an equililibrium between complexes having similar geometries, but with the long and intermediate bond directions interchanged. The behaviour is in contrast to that of the pure copper(II) complex, where the thermal properties appear to be influenced by cooperative interactions.
Synthesis, Crystal Structure of 1‐D Double‐helical Chain Manganese(II) Coordination Polymer Constructed by 2,2′‐bpy and Flexible Dicarboxylate Ligand with Strong Fluorescent Emission
Authors: Yang Li , Yu Wei , Zhang Tong‐Lai , Zhang Jian‐Guo , Wang Shao‐Zong , Wu Rui‐Feng
Published: August 2007

A new coordination polymer [Mn2(nbdoa)2(2,2′‐bpy)2]n was obtained by hydrothermal reaction, which was constructed by 2,2′‐bpy and flexible ligand 2‐nitro‐benzene‐1,4‐di(oxyacetate). The crystal structure reveals that there exists 1‐D double‐helical chain, which is connected to 2‐D network via π‐π stacking interactions. The thermal analysis shows that the complex begins to decompose at 567 K. The luminescence property was investigated and the complex shows photoluminescence in the solid state at room temperature.
Tin(IV) Complexes with Thiosemicarbazide and 4‐Methyl‐3‐thiosemicarbazide Derivatives
Authors: Calatayud David G. , López‐Torres Elena , Mendiola Antonia , Procopio Jesús R.
Published: August 2007

Five new complexes were isolated from a CH2Cl2 solution of SnCl4 and the ligands benzil bis(thiosemicarbazone) L1H6, benzil bis(4‐methyl‐3‐thiosemicarbazone) L1Me2H4, 5‐methoxy‐5,6‐diphenyl‐4,5‐dihydro‐2H‐[1,2,4]‐triazine‐3‐thione, L2H2OMe and 5‐methoxy‐4‐methyl‐5,6‐diphenyl‐4,5‐dihydro‐2H‐[1,2,4]‐triazine‐3‐thione, L2MeHOMe. The characteristics of the complexes depend on the ligand. Compounds were characterized by elemental analysis, mass spectrometry, IR, 13C and 119Sn CP/MAS NMR spectroscopy.
Synthesis, Structure and Magnetic Characterization of Two Phosphate Compounds Related with the Mineral Struvite: KNiPO4μ·μ6H2O and NaNiPO4μ·μ7H2O
Authors: Trobajo Camino , Salvadó Miguel A. , Pertierra Pilar , Alfonso Belén F. , Blanco Jesús A. , Khainakov Serguei A. , García José R.
Published: August 2007

Two new phosphate compounds, KNiPO4·6H2O and NaNiPO4·7H2O, have been synthesized, identified and their crystal structure studied by powder X‐ray diffraction. KNiPO4·6H2O crystallizes in the monoclinic system, with lattice parameters a = 6.8309(3) Å, b = 11.0610(4) Å, c = 6.1165(2) Å, and angle β = 91.045(2)°, volume of the unit cell V = 462.07(3) Å3, space group P21, and Z = 2, while NaNiPO4·7H2O does so in the tetragonal system with a = 6.7390(2) Å, c = 10.9690(4) Å, V = 498.15(4) Å3, space group P42/mmc, and Z = 2. KNiPO4·6H2O has the structure as the struvite analogue KMgPO4·6H2O, whereas NaNiPO4·7H2O is isostructural with the compound NaMgPO4·7H2O. Neither material presents a magnetic order in the range of temperatures measured from 300 K down to 1.8 K.
LV systolic impairment in patients with asymptomatic coronary heart disease and type 1 diabetes is related to coronary atherosclerosis, glycaemic control and advanced glycation endproducts
Authors: Steine Kjetil , Larsen Jakob R. , Stugaard Marie , Berg Tore Julsrud , Brekke Magne , Dahl‐Jørgensen Knut
Published: August 2007

Aims:

To evaluate whether heart failure in type 1 diabetes is linked to poor glycaemic control, coronary atherosclerosis or advanced glycation endproducts (AGEs).

Methods:

Twenty six patients with type 1 diabetes (mean duration 32±5years), and 16 age matched controls were recruited. Mean HbA1c through 18years (HbA1c18), serum levels of AGEs and coronary atherosclerotic burden (CAB) were determined by IVUS. Peak tissue velocities and strain by tissue Doppler imaging were measured in 12 LV regions as an evaluation of LV function.

Results:

Systolic tissue velocity was inversely correlated to CAB (r=0.53, p<0.01), to HbA1c18 (r=0.46, p<0.05) and to the duration of diabetes (r=0.46, p<0.05). Systolic strain was inversely correlated to HbA1c18 (r=0.45, p<0.05), to duration of diabetes (r=0.41, p<0.05), and tended to correlate with AGEs (r=0.37, p=0.07). In multiple regression analyses, CAB and HbA1c18 were significant independent predictors for systolic velocity, while AGEs and duration of diabetes were significant predictors of systolic strain.

Conclusion:

LV systolic function was impaired by increasing coronary atherosclerosis and worsening of glycaemic control. AGEs might be another mechanism for the increased risk of heart failure in type 1 diabetes.
Evidence for fast conformational change upon ligand dissociation in the HemAT class of bacterial oxygen sensors
Authors: Mokdad Audrey , Nissen Mark , Satterlee James D. , Larsen Randy W.
Published: August 2007

Here we report the results of transient absorption and photoacoustic calorimetry studies of CO photodissociation from the heme domain of the bacterial oxygen sensor HemAT‐Bs. The results indicate that CO photolysis is accompanied by an overall ΔH of −19 kcal mol−1 and ΔV of +4 ml mol−1 as well as a red‐shifted kinetic difference spectrum all occurring in <50 ns. Analysis of the ΔH/ΔV reveals that a conformational change takes place with a ΔH
conf of −40 kcal mol−1 and ΔV
conf of −22 ml mol−1. These thermodynamic changes are consistent with an increase in the solvent accessible surface area of the protein upon ligand dissociation, as observed in the X‐ray structure of the ferric CN‐bound and CN free forms of HemAT‐Bs.
Rev‐erbα gives a time cue to metabolism
Authors: Duez Hélène , Staels Bart
Published: August 2007

Normal physiological processes are under control of circadian rhythms. Moreover, certain pathological events, such as cardiovascular accidents (myocardial infarction, stroke) occur more frequently at specific times of the day. Recent observations demonstrate a causal relationship between alterations in circadian rhythmicity and metabolic disorders. Disruption of clock genes results in dyslipidemia, insulin resistance and obesity, all predisposing to atherosclerosis. The nuclear receptor Rev‐erbα is part of the clock circuitry and plays an important role in keeping proper timing of the clock. Rev‐erbα also regulates lipid metabolism, adipogenesis and vascular inflammation. Interestingly, Rev‐erbα also cross‐talks with several other nuclear receptors involved in energy homeostasis. Therefore Rev‐erbα may serve to couple metabolic and circadian signals.
Seasonal variations in the Amazon plume‐related atmospheric carbon sink
Authors: Cooley S. R. , Coles V. J. , Subramaniam A. , Yager P. L.
Published: August 2007

The Amazon River plume is a highly seasonal feature that can reach more than 3000 km across the tropical Atlantic Ocean, and cover ∼2 million km2. Ship observations show that its seasonal presence significantly reduces sea surface salinity and inorganic carbon. In the western tropical North Atlantic during April–May 2003, plume‐influenced stations exhibited surface DIC concentrations lowered by as much as 563 μmol C kg−1 (∼28%) and pCO2 as low as 201 μatm. We combine our data with other data sets to understand the annual uptake and seasonal variability of the plume‐related CO2 sink. Using flux estimates from all seasons with monthly plume areas determined by satellite, we calculate the annual carbon uptake by the outer plume alone (28 < S < 35) to be 15 ± 6 TgC yr−1. Diazotroph‐supported net community production enhanced the air‐sea CO2 disequilibrium by 100x and reversed the typical CO2 outgassing from the tropical North Atlantic. The carbon sink in the Amazon plume depends on climate‐sensitive conditions that control river hydrology, CO2 solubility, and gas exchange.
Characteristics of inertio‐gravity waves revealed in rawinsonde data observed in Korea during 20 August to 5 September 2002
Authors: Chun Hye‐Yeong , Goh Jung‐Suk , Kim Young‐Ha
Published: August 2007

Characteristics of inertio‐gravity waves (IGWs) observed at six operational rawinsonde stations in Korea from 20 August to 5 September 2002 and their relationship with convective sources are investigated. Several types of convective systems, including mesoscale convective complexes and Typhoon Rusa, passed the Korean peninsula during the observing period. To categorize the observed waves with and without convective sources, wet and dry periods are defined at each observing site using hourly precipitation and satellite data. Although waves with extremely large values of intrinsic frequency and vertical wavelength are observed mostly in wet periods, the mean values of wave parameters for wet and dry periods are similar. Low‐frequency IGWs can originate far from and long before the observing sites, implying that it is unreasonable to correlate convective sources and observed waves at the same location and time. For better correlation of the observed waves and their sources, a three‐dimensional ray‐tracing model is used. A new wet case is defined on the basis of the occurrence of convection when and where a ray locates in mid‐to‐upper troposphere. Characteristics of the observed waves for new wet and dry cases differ significantly: the intrinsic frequency is larger but the horizontal wavelength is much smaller for wet than dry cases. Sources for wet cases are mostly convective clouds located northeast and southeast of the observing sites below 5 km. This is clearly distinguished from dry cases, where sources are located mostly in the northwest above 15 km and southeast far from the observing sites below 5 km.
An adaptive neural network embedded genetic algorithm approach for inverse water quality modeling
Authors: Zou Rui , Lung Wu‐Seng , Wu Jing
Published: August 2007

This paper proposes a neural network (NN)‐embedded genetic algorithm (GA) approach for solving inverse water quality modeling problems to overcome the computational bottleneck of inverse modeling by replacing a water quality model with an efficient NN functional evaluator. An existing one‐step, NN‐embedded GA approach is found incapable of solving an inverse water quality modeling problem because it tends to fail in guiding the global search process to converge toward the near optima. As a remedy, an adaptive NN‐GA approach is proposed to achieve a gradual convergence toward the near optima through an iterative network learning method. The proposed approach is applied to a full‐scale, numerical example, and the result shows that the adaptive NN‐GA approach is capable of obtaining near‐optimal solutions for the inverse problem of a complicated water quality model.
Rheologic controls on slab dynamics
Authors: Billen Magali I. , Hirth Greg
Published: August 2007

Several models have been proposed to relate slab geometry to parameters such as plate velocity or plate age. However, studies on the observed relationships between slab geometry and a wide range of subduction parameters show that there is not a simple global relationship between slab geometry and any one of these other subduction parameters for all subduction zones. Numerical and laboratory models of subduction provide a method to explore the relative importance of different physical processes in determining subduction dynamics. Employing 2‐D numerical models with a viscosity structure constrained by laboratory experiments for the deformation of olivine, we show that the observed range in slab dip and the observed trends between slab dip and convergence velocity, subducting plate age, and subduction duration can be reproduced without trench motion (i.e., slab roll‐back) for locations away from slab edges. Successful models include a stiff slab that is 100–1000 times more viscous than previous estimates from models of plate bending, the geoid, and global plate motions. We find that slab dip in the upper mantle depends primarily on slab strength and plate boundary coupling, with a small dependence on subducting plate age. Once the slab sinks into the lower mantle the primary processes controlling slab evolution are (1) the ability of the stiff slab to transmit stresses up dip, (2) resistance to slab descent into the higher‐viscosity lower mantle, and (3) subduction‐induced flow in the mantle‐wedge corner.
Hydrothermal activity on the ultra‐slow spreading southern Knipovich Ridge
Authors: Connelly D. P. , German C. R. , Asada M. , Okino K. , Egorov A. , Naganuma T. , Pimenov N. , Cherkashev G. , Tamaki K.
Published: August 2007

We report first evidence for hydrothermal activity from the southern Knipovich Ridge, an ultra‐slow spreading ridge segment in the Norwegian‐Greenland Sea. Evidence comes from optical backscatter anomalies collected during a systematic side‐scan sonar survey of the ridge axis, augmented by the identification of biogeochemical tracers in the overlying water column that are diagnostic of hydrothermal plume discharge (Mn, CH4, ATP). Analysis of coregistered geologic and oceanographic data reveals that the signals we have identified are consistent with a single high‐temperature hydrothermal source, located distant from any of the axial volcanic centers that define second‐order segmentation along this oblique ridge system. Rather, our data indicate a hydrothermal source associated with highly tectonized seafloor that may be indicative of serpentinizing ultramafic outcrops. Consistent with this hypothesis, the hydrothermal plume signals we have detected exhibit a high methane to manganese ratio of 2–3:1. This is higher than that typical of volcanically hosted vent sites and provides further evidence that the source of the plume signals reported here is most probably a high‐temperature hydrothermal field that experiences some ultramafic influence (compare to Rainbow and Logachev sites, Mid‐Atlantic Ridge). While such sites have previously been invoked to be common on the SW Indian Ridge, this may be the first such site to be located along the Arctic ultra‐slow spreading ridge system.
Asymmetric thin current sheets in the Earth's magnetotail
Authors: Malova H. V. , Zelenyi L. M. , Popov V. Y. , Delcourt D. C. , Petrukovich A. A. , Runov A. V.
Published: August 2007

In a frame of self‐consistent model of thin current sheets (TCSs), where the tension of magnetic field lines is balanced by the inertial force of ion motion, we investigated the influence of the asymmetry of plasma sources on the structure and spatial localization of the equilibrium solution. For simplicity only one ion source is considered. It is shown that the asymmetry of plasma sources does not modify dramatically the bulk of the current carried by ions at meandering orbits. Negative diamagnetic currents are significantly stronger at the side of a plasma source due to enhanced plasma density in this region. The center of TCS is displaced to the opposite side of the plasma source to keep the pressure balance. One could speculate that this phenomenon might be a cause of flapping motions of the TCS due to the natural variability of plasma sources.
Estimating properties of concentrated parallel electric fields from electron velocity distributions
Authors: Vedin Jörgen , Rönnmark Kjell , Bunescu Costel , Marghitu Octav
Published: August 2007

Information about the magnitude of the field‐aligned potential drop along auroral field lines is usually derived from the velocity distribution of the particles. So far the electron distribution functions have been used systematically only to derive the total potential drop above the satellite, by setting it equal to the peak energy of the electrons. When the electrons are accelerated by a concentrated electric field, their velocity distribution will have features different from those produced by a weak, spread‐out, electric field. Quantifying these features, we obtain a method that can provide details about the strength and thickness of a concentrated electric field layer when it is located not too far above the satellite. The method is checked and proved to work satisfactory on simulated and measured data.
Heat‐model analysis of wall rocks below a diabase sill in Huimin Sag, China compared with thermal alteration of mudstone to carbargilite and hornfels and with increase of vitrinite reflectance
Authors: Wang Dayong , Lu Xiancai , Zhang Xuejun , Xu Shijin , Hu Wenxuan , Wang Liangshu
Published: August 2007

This paper presents an application of heat flow modeling in a study on the thermal alteration of the underlying sedimentary rocks caused by an isolated intrusive sill in Huimin Sag, Bohai Bay Basin, China. It is found that during the cooling of the sill, the assignment of the heat transferred into its both sides can be acquired according to the ratio of the thickness of the overlying and underlying thermally altered rocks. Heat‐transfer modeling indicates that the transition temperatures for the alteration from calcareous mudstone to carbargilite and successively to hornfels are identified as 245 ± 9°C and as 449 ± 19°C, respectively. The peak temperature calculated from vitrinite reflectance higher than 3.0% of the altered wall rocks is generally lower than expected values. Especially in the hornfels zone, vitrinite reflectance ever decreased with increased temperature. The thermal alteration of mudstone is possibly an important factor causing such a decrease.
Parameterization of cloud droplet formation in large‐scale models: Including effects of entrainment
Authors: Barahona Donifan , Nenes Athanasios
Published: August 2007

This work offers for the first time a comprehensive parameterization suitable for large‐scale models which is robust, computationally efficient, and from first principles links chemical effects, aerosol heterogeneity and entrainment with cloud droplet formation. The parameterization is based on the entraining ascending parcel model framework; mixing of outside air is parameterized in terms of a per‐length entrainment rate. The integration of the droplet growth is done using the “population splitting” concept of Nenes and Seinfeld (2003). Formulations for lognormal and sectional aerosol representations are given, as well as simplifications that allow the treatment of entrainment with high computational efficiency without loss of accuracy. The concept of “critical entrainment,” a value beyond which droplet activation is not favored, is introduced and shown that it is important for defining (1) whether or not entrainment effects have an impact on droplet formation and (2) the characteristic temperature and pressure for cloud droplet formation. The performance of the parameterization was evaluated against a detailed numerical parcel model over a comprehensive range of droplet formation conditions. The agreement is always very good (mean relative error 2.3% ± 21%); errors tend to increase as entrainment approaches the critical value, but are never above 40%.