Dioxygen Affinities and Catalytic Epoxidation Performanceof Transition-Metal Hydroxamates

The dioxygen affinities and catalytic epoxidation performance of transition-metal hydroxamates were investigated for the first time. The effects of substituents on these properties were also discussed in the paper.

Dioxygen Affinities and Catalytic Oxidation Performance of Cobalt (Ⅱ)Complexes with N—Aryl Hydroxamic Acid

The oxygenation of cobalt (II) hydroxamates (CoL2) and its catalytic performance in oxidation of p-xylene to p-toluic acid (PTA) were examined. The effects of X and Y bonded to hydroxamate group on dioxygen affinities and catalytic oxidation performance were also investigated.

Dioxygen Affinities and Catalytic Oxidation Performance of Co （Ⅱ） Complexes with Phenol Ether Bridged Dihydroxamic Acids

The oxygenation constants and thermodynamic parameter （△H°, △S°） of a series of novel Co （Ⅱ） complexes with phenol ether bridged dihydroxamic acids CoL^1-CoL^6 were measured, their catalytic performance in oxidation of p-xylene to p-toluic acid （PTA） were examined. The modulation of O2-binding capabilities and catalytic oxidation activities by X （X = Cl, OCH3） and Y （Y = H, CH3, Cl） groups bonded to the aromatic rings of the Co （Ⅱ） complexes were investigated.

Affinities Between “The Grapes of Wrath” and the “Bible”──A Study of Biblical Allusions

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Metal affinities in single and multiple ion adsorption reaction at sulfide mineral surfaces

Sulfide minerals are found in porous media in both aerobic and anaerobic environments, they should have a high affinities for certain metals. The relative binding affinities and reaction processes for 10 metal/metalloid ions reacting with four sulfide mineral surfaces has been defined.The order of reactivity is chalcocite > pyrite > galena >> sphalerite. For any particular metal and mineral, the greater reactivity occurs in the single-ion metal system except Ag(I) on pyrite and Cu(II) on galena.Both precipitation and adsorption reaction can decrease metal ion mobility on porous media, the order of metal mobility in the presence of the four sulfide minerals is predicted to be: Zn(II), Cd(II) and Ni(II) - mobile; Cu(II), Pb(II), Fe(III), As(III) and Cr(III) - variable mobility and Ag(I) - immobile.MINTEQA1 predictions on metal phase distribution / partitioning compared quite well with those observed experimentally. Solubility product considerations, intrinsic acidity constant of the mineral, EH, pH and the carbonate equilibrium are major factors controlling the phase distribution of metals reacting singularly or in combination with sulfide mineral surfaces.

Dioxygen Affinities and Biomimetic Catalytic Oxidation Performance of Transition-metal Complexes with Unsymmetrical Bis-Schiff Bases

The oxygenation constants and thermodynamic parameter (ΔHo, ΔSo) of Co (II) complexes with unsymmetrical bis-Schiff baeses were measured and their Mn(III) complexes as models of mimicking monooxygenase were employed to catalyze epoxidation of styrene. The effect of substituent R in a salicylidene of ML1~ML4 [ M = Co (II), Mn (III)Cl ] on the dioxygen affinities and biomimetic catalytic oxidation performance were also investigated. Among them, the MnL4Cl containing a pendant benzoaza crown ether ring showed highest conversion and selectiviy up to 54.9% and 96.9% respectively.

Petrogenesis of Triassic Mafic Complexes with MORB/OIB Affinities from the Western Garzê-Litang Ophiolitic Mélange, Central Tibetan Plateau

There is a general consensus that most ophiolites formed above subduction zones(Pearce,2003),particularly during forearc extension at subduction initiation(Shervais,2001;Stern,2004;Whattam and Stern,2011).'Supra-Subduction zone'(SSZ)ophiolites such as the well-studied Tethyan ophiolites,generally display a characteristic sequential evolution from mid-oceanic ridge basalts(MORBs)to island arc tholeiities(IATs)or bonites(BONs)(Pearce,2003;Dilek and Furnes,2009,2011),which were generated in sequence from the decompression melting of asthenospheric mantle and partial melting of subduction-metasomatized depleted mantle(Stern and Bloomer,1992;Dilek and Furnes,2009;Whattam and Stern,2011).However,ophiolites with MORB and/or oceanic-island basalt(OIB)affinities are rare,and their origin and tectonic nature are poorly understood(Boedo et al.,2013;Saccani et al.,2013).It is interesting that the composition of these ophiolites from the central Tibetan Plateau(CTP)is dominated by MORBs and minor OIBs and a distinct lack of IATs and BONs,which is inconsistent with most ophiolites worldwide(Robinson and Zhou,2008;Zhang et al.,2008).But the generation and tectonic nature of these ophiolites are still controversial.*In this study,we present new geochronological,mineralogical and Sr-Nd isotopic data for the Chayong and Xiewu mafic complexes in the western Garzê-Litang suture zone(GLS),a typical Paleo-Tethyan suture crossing the CTP(Fig.1).The Triassic ophiolite in the western GLS has been described by Li et al.(2009),who foundthat it mainly consists of gabbros,diabases,pillow basalts and a few metamorphic peridotites.The ophiolite has been tectonically dismembered and crops out in Triassic clastic rocks and limestones as tectonic blocks.The Chayong and Xiewu mafic complexes are generally regarded as important fragments of the Triassic ophiolites(e.g.,Jin,2006;Li et al.,2009).Zircon LA-ICP-MS U-Pb ages of234±3 Ma and 236±2 Ma can be interpreted as formation times of the Chayong and Xiewu mafic complexes,respectively.The basalts and gabbros of the Chayong complexexhibitenrichedMORB(E-MORB)compositional affinities except for a weak depletion of Nb,Ta and Ti relative to the primitive mantle,whereas the basalts and gabbros of the Xiewu complex display distinct E-MORB and OIB affinities.The geochemical features suggest a probable fractionation of olivine±clinopyroxene±plagioclase as well as insignificant crustal contamination.The geochemical and Sr-Nd isotopic data reveal that the Chayong mafic rocks may have been derived from depleted MORB-type mantle metasomatized by crustal components and Xiewu mafic rocks from enriched lithosphericmantlemetasomatizedbyOIB-like components.The ratios of Zn/Fet,La/Yb and Sm/Yb indicate that these mafic melts were produced by the partial melting of garnet+minor spinel-bearing peridotite or spinel±minor garnet-bearing peridotite.We propose thatback-arcbasinspreadingassociated with OIB/seamount recycling had occurred in the western GLS at least since the Middle Triassic times,and the decompression melting of the depleted MORB-type asthenospheremantleandpartialmeltingof sub-continental lithosphere were metasomatized by plume-related melts,such as OIBs,which led to the generation of the Chayong and Xiewu mafic melts.

Ionization Potentials and Electron Affinities of Cu_n Atomic Clusters

Ionization potentials and electron affinities of Cux (n = 2-7) atomic clusters with the optimal geom etries have been calculated by use of SC F-Xa-SW method and Slater's transition state theory. Theo retical calcuIations show that the ionization potentiaIs and electron affinities of Cu. (n = 2-7) atom ic clusters have a sharp even / odd alternation with increasing their sizes, which are related to the electronic structure of Cun atomic clusters. The theoretical results are consistent with the related ex perimental ones.

DFT Study of Electron Affinities of o-, m-,p-Halobenzyl Radicals

The electron affinities of the isomer XC6H4CH2/ XC6H4CH2- (X=F, Cl, Br) species have been determined using seven density functional theory (DFT) methods. The basis set used in this work is of double-ζ plus polarization quality with additional diffuse s- and p-type functions, denoted DZP++. Three different types of the neutral-anion energy separations reported in this work are the adiabatic electron affinity (EAad), the vertical electron affinity (EAvert), and the vertical detachment energy (VDE). The most reliable adiabatic electron affinities are obtained at the DZP++ BPW91, BP86, and B3LYP level of theory. The BPW91 methods are the closest to the experiment values; The BHLYP method predicts the smallest EAad and B3P86 method predicts the largest EAad, which are the worst reliable methods. In addition, for a given halogen substituent, the meta isomer has the largest electron affinity and the para isomer has the smallest.

Prediction of the Atomic Electron Affinities Using a Wavelet Neural Network

Wavelet Neural Network (WNN) was employed in a rapid calculation of the atomic electron affinities, with atomic ionization potentials and atomic electron configurations chosen as input parameters. Many unmeasured values were obtained, and the estimates appeared to be sufficiently accurate for potential applications.

ON PHYTOGEOGRAPHICAL AFFINITIES OF THE FOREST FLORAS BETWEEN EAST CHINA AND JAPAN

The flora of the eastern China is the main part of Sino-Japaners floristic region. It shows from the analysis and comparison that the floristic relation of East China with Japan is closer than that with northeast China and Korea. The similarity indices of genera and species of seed plants in the two regions are very high, being 72.6% and 43.3% respectively. The structure and species composition of broad-leaval evergreen forests in the two regions are also similar, and there exist many corresponding communities, such as the forests of Castanopsis carlesii and C. sieboldii. Many plants in East China are conspecific with there in Japan, such as Cercidiphyllum japonicum, Magnolia sieboldii, Nandina domestica etc. Though the genera of Ginkgo, Liriodendron, Sassafras etc. existing now in China are extinct from Japan, their fossils have been discovered from the Tertiary strata in Japan. It seems to indicate that the phytogeographical affinities between East China and Japan are closer in ancient the than it is now, and both of the forest floras originated from the same flora. The flora in Japan did not evolve independently until it separated from Chinese continent and drifted northeastwards in the late period of the Tertiary.

Dioxygen Affinities and Biomimetic Catalytic Performance of Transition-metal Complexes with Benzoin Schiff Bases

The oxygenation constants of transition-metal complexes with benzoin Schiff bases were measured and these complexes were first employed as models for mimicking monooxygenase in catalytic epoxidation of styrene. The highest conversion and selectivity were up to 39.6% and 100% respectively at ambient temperature and pressure. The effects of structures of the bridge group R in the ligands on the dioxygen affinities and catalytic activities to epoxidize styrene were also investigated.

Dioxygen Affinities and Biomimetic Catalytic Performance of Transition-metal Complexes with Crowned Bis-Schiff Bases

The dioxygen affinities and biomimetic catalytic performance of transition-metal complexes with (15-crown-5) salophen and its substituted derivatives Mere examined. The oxygenation constants of Co(II) complexes with crowned bis-Schiff bases were measured and their Mn(III) complexes were employed as models to mimic monooxygenase in catalytic epoxidation of styrene. The highest conversion and selectivity were up to 57.2% and 100% respectively at ambient temperature and pressure. The effects of crown ether ring and substituents R on the dioxygen affinities and catalytic activities were also investigated through comparing with the uncrowned analogues.

Dioxygen affinities and catalytic oxidation performance of cobalt(Ⅱ) hydroxamates with benzo-15-crown-5 pendants

The oxygenation constants （Ko2） of cobalt（Ⅱ） hydroxamates （CoL^1 2-CoL^3 2） with benzo-15-crown-5 （B15C5） pendants were measured over the range of -5 to ＋20 ℃, and the values of thermodynamic parameters （ΔH^0 and ΔS^0） were calculated based on these （Ko2） values, Meanwhile, these crowned complexes were employed to the oxidation for p-xylene to p-toluic acid with air at 110Δ under normal atmospheric pressure. The effects of B15C5 pendant and the length of chain bonded to B15C5 in these complexes on the O2-binding capabilities and oxidation for p-xylene were investigated with the comparison of crown-free analogues CoL^4 2.

Quantitative Structure-Activity Relationships in the Lithium and Sodium Affinities of n-Alkyl Fluorides

B3LYP/6-31+g (d, p) method was used to calculate the lithium and sodium affinities of n-alkyl fluoride. These affinities were found to obey the Holmes relationship, i.e. they correlate linearly with the quotient n/(n+1), where n is the number of carbon atoms in the alkyl chain. From the correlation the limiting values of lithium and sodium affinities for very long alkyl chain were predicted to be 153.3 kJ/mol and 108.4 kJ/mol, respectively.

Theoretical Studies on Structures and Electron Affinities of 5-and 6-Halouracils

The molecular structures and electron affinities of 5- and 6-halouracils（XU, X=F, Cl, Br） were determined by means of five different density functional methods. The basis set used in this work is of double-（plus polariza- tion（DZP） quality with additional diffuse s- and p-type functions, denoted DZP＋＋. The geometries were fully optimized with each density functional theory（DFT） method, and discussed. Three different types of the neutral-anion energy separations reported in this work are the adiabatic electron affinity（AEA）, the vertical electron affinity（VEA）, and the vertical detachment energy（VDE）. An excellent agreement between our B3LYP results and those obtained by other calculations regarding the structural modifications and electron affinities of neutral and anion 5XU was found. The differences in charge distribution between uracil and halogenated uracils were indicated, thus the ability to form the hydrogen bonds of halogenated uracils was discussed. It shows the applicability of the DFT/DZP＋＋ method to predict the similar molecular models at a highly economical computational cost.

Multiply Charged Anions,Maximum Charge Acceptance,and Higher Electron Affinities of Molecules,Superatoms,and Clusters

The addition of electrons to form gas-phase multiply charged anions(MCAs)normally requires sophisticated experiments or calculations.In this work,the factors stabilizing the MCAs,the maximum electron uptake of gas-phase molecules,X,and the electronic stability of MCAs X^(Q-),are discussed.The drawbacks encountered when applying computational and/or conceptual density functional theory(DFT)to MCAs are highlighted.We develop and test a different model based on the valence-state concept.As in DFT,the electronic energy,E(N,v_(ex)),is a continuous function of the average electron number,N,and the external potential,v_(ex),of the nuclei.The valence-state-parabola is a second-order polynomial that allows extending E(N,v_(ex))to dianions and higher MCAs.The model expresses the maximum electron acceptance,Q_(max),and the higher electron affinities,A_Q,as simple functions of the firstelectron affinity,A_1,and the ionization energy,I,of the"ancestor"system.Thus,the maximum electron acceptance is Q_(max,calc)=1+12A_1/7(I-A_1).The ground-state parabola model of the conceptual DFT yields approximately half of this value,and it is termed Q_(max,GS)=?+A_1/(I-A_1).A large variety of molecules are evaluated including fullerenes,metal clusters,super-pnictogens,super-halogens(OF_3),super-alkali species(OLi_3),and neutral or charged transition-metal complexes,AB_(m )L_n^(0/+/-).The calculated second electron affinity A_(2,calc)=A_1-(7/12)(I-A_1)is linearly correlated to the literature references A_(2,lit) with a correlation coefficient R=0.998.A_2 or A_3 values are predicted for further 24 species.The appearance sizes,n_(ap)^(3-),of triply charged anionic clusters and fullerenes are calculated in agreement with the literature.

Phytogeographical Affinities of Forest Floras between China and Japan

The flora of eastem China is the main part of Sino-Japanese floristic region. It shows by the analysis and com-parison that the floristic relations of Eastem China with Japan are closer than that ofnortheast China with Korea. The simi-larity indices of genera and species of seed plants in the two regions are very high, being 72.6% and 43.3% respectively.The strure and species compositi6n of broad-leaved evergreen forests in the two regions are also similar, in which there'exist the corresponding communities, such as the forests of Castanopsis carlesii,C.Sieboldii.. Many plants in Easter Chinaare nonspecilic with those in Japan, e. g, Cercidiphyllum japonicum, Magolia sieboldii, Nandina domestica etc.. Though thegnera Ginkgo, Liriodendron, Sassafixis etc. existing now in China are extinct from Japan, their fossils have been discov-ered from the Tertiary Strata in Japan. It seems to indicate that the Phytogeographical affinities between Japan and E. Chinawas closer in ancient time than it is now; and both of the forest floras originated from one same flora. The flora in Japan did not evolve indepently until it separated from Chinese continent and drifted to northeast in the late period of the Tertiary.

Structures,Electron Affinities and Vibrational Frequencies of SF_5OX/SF_5OX^-(X=F,Cl,Br)

The molecular structures,electron affinities,vibrational frequencies and IR intensities of the SF5OX/SF5OX-（X=F,Cl,Br）species have been determined by four different density functional theory（DFT）methods（B3LYP,BHLYP,BP86,BLYP）in conjunction with DZP＋＋ basis set.The BHLYP method predicts the best geometry parameters.The adiabatic electron affinities（EAad）predicted by the B3LYP/DZP＋＋ method are 4.36 eV（SF5OF）,4.13 eV（SF5OCl）,4.12 eV（SF5OBr）,respectively.Large electron affinity implies the corresponding anions are stable.The total intensities in the near IR ＂window＂ of the anions SF5OX-（X=F,Cl,Br）at B3LYP level are 1 602 km/mol（SF5OF-）,1 868 km/mol（SF5OCl-）and 1 916 km/mol（SF5OBr-）,respectively,larger than those of the corresponding neutrals.It suggests that SF5OX/SF5OX-（X=F,Cl,Br）may be used to ＂warm＂ Mars.

Principles of amino-acid–ribonucleotide interaction revealed by binding affinities between homogeneous oligopeptides and singlestranded RNA molecules

We have determined the binding strengths between ribonucleotides of adenine(A),guanine(G),uracil(U),and cytosine(C)in homogeneous single-stranded ribonucleic acids(ssRNAs)and homo-decapeptides consisting of 20 common amino acids.We use a bead-based fluorescence assay for these measurements in which decapeptides are immobilized on the bead surface and ssRNAs are in solutions.The results provide a molecular basis for analyzing selectivity,specificity,and polymorphisms of amino-acid–ribonucleotide interactions.Comparative analyses of the distribution of the binding energies reveal unique binding strength patterns assignable to each pair of amino acid and ribonucleotide originating from the chemical structures.Pronounced favorable(such as Arg–G)and unfavorable(such as Met–U)binding interactions can be identified in selected groups of amino acid and ribonucleotide pairs that could provide basis to elucidate energetics of amino-acid–ribonucleotide interactions.Such interaction selectivity,specificity,and polymorphism manifest the contributions from RNA backbone,RNA bases,as well as main chain and side chain of the amino acids.Such characteristics in peptide–RNA interactions might be helpful for understanding the mechanism of protein–RNA specific recognition and the design of RNA nano-delivery systems based on peptides and their derivatives.