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Various studies are employed to describe the change in the redox behavior of plastocyanin, a blue copper protein, at low pH by the protonation of the solvent-exposed copper-coordinating histidine, as it can also help in the down regulation of photosynthesis. It is proven that the single, as well as the double mutants do not change the protonation behavior and hence the interactions have no influence.

Fluorescently labeled models of the prion protein that allow prion-prion (PrP-PrP) interactions and metal binding ([Cu.sup.2+] and [Zn.sup.2+]) to be investigated on the molecular level were developed. The results show that PrP-PrP interactions are promoted by addition of [Cu.sup.2+] and [Zn.sup.2+] and glutamine and tryptophan residues also play an important role in PrP-PrP interactions.

The ceramic liquid droplet of Cu[O.sub.x]-added Bi[O.sub.x] at high temperature in vacuum is studied. The Cu[O.sub.x]-added Bi[O.sub.x] is found to be stable in the liquid phase at high temperature in vacuum, making it useful for cleaning the CaO impurities on MgO single crystal surface, resulting in the preparation of the atomically flat MgO(001) surface.

The instrumented nanoindentation test is used to investigate the mechanical properties and deformation behaviors of copper with different grain sizes. The results have shown that the critical shear stresses for the initiation of plastic deformation in the copper specimens with large grain sizes are close to the theoretical value and comparatively much lower for electroless copper films with an ultrafine grain size.

The synthesis, X-ray crystal structure and magnetic studies of an example of organic/inorganic spin hybrid clusters extended in infinite ladder-type chain [[Cu[([C.sub.5][F.sub.6]H[O.sub.2]).sub.2]].sub.7][([C.sub.35][H.sub.35][N.sub.5][O.sub.4]).sub.2] formed by the reaction of a high spin nitronylnitroxide biradical [C.sub.35][H.sub.35][N.sub.5][O.sub.4] and bis(hexafluroacetylacetonate)copper(II) are described. The analysis has highlighted the importance of considering unexpected and complex regiospecific interactions due to the structural novelty.

The relative proportions of metal residing in ore in the lithosphere, in use in products providing services, and in waste deposits measure our progress from exclusive use of virgin ore toward full dependence on sustained use of recycled metal. In the U.S. at present, the copper contents of these three repositories are roughly equivalent, but metal in service continues to increase. Providing today's developed-country level of services for copper worldwide (as well as for zinc and, perhaps, platinum) would appear to require conversion of essentially all of the ore in the lithosphere to stock-in-use plus near-complete recycling of the metals from that point forward. copper | material flow analysis | metal services

Abstract -- It was shown that anodic voltammetry at graphite electrodes can be used for determining thiourea in solutions of copper refinery electrolytes. The proposed procedure involves dilution, the addition [...]

Abstract -- 1-(2-Thenoyl)-4-trifluoro-2-[2-hydroxy-3-sulfo-5-nitrophenylazo]butadione-1,3 ([H.sub.2]L) was synthesized from 2-thenoyltrifluoroacetone. The formation of a copper(II) complex of the synthesized reagent was studied in the presence and absence of 8-hydroxyquinoline (HR). Monoligand [Cu(HL)[.sub.2]] [...]

The synthesis and structural characterization of polynuclear copper (II) complexes derived from 1,3-bis (dimethylamino)-2-propanolato is described. The magnetic behavior of these complexes has been investigated, showing strong antiferromagnetic coupling in all the cases.

The synthesis of supramolecular copper hydroxide tennis balls by self-assembly is described. The structure of this compound was determined by using X-ray crystallography.

Density functional theory calculations are conducted to explore the potential energy surface (PES) associated with the gas-phase reactions between ethylenediamine (En) and Cu(super +). The structures and bonding characteristics of the different stationery points in the PES are investigated at the B3LYP/6-311G(d,p) level.

Heterobinuclear copper (II)- zinc (II) complexes and their homobinuclear dicopper (II) counterparts (1-4) of two asymmetric ligands (H (sub 2) L (super 1) and H (sub 2) L (super 2)), based on 2-amicoyclopent-1-ene- 1-dithicarboxylate are reported. The ligands are capable of providing both donor set and coordination number asymmetry in tandem.

Sulfur bridging interaction between three cis-planar Ni(super II)-S2N2 complex and Ni(super II), Cu(super I, II), Zn(super II), and Hg(super II) reactants are investigated by synthesis and X-ray crystal structures of some 24 complexes. This work is stimulated by recent crystallographic structures of the A-cluster of carbon monoxide dehyrogenase/acetylcoenzeme a synthase.

Diaryl hydrazides prepared from the Pd(0)- or Cu(I)-catalyzed coupling reactions of aryl hydrazides and aryl halides underwent the acid-catalyzed rearrangements to a series of previously unknown 2,2'-diaminobiaryls in good overall yields. The mildness of the reaction conditions allows the presence of various functional groups.

The morphology, structure, and magnetism of Fe films on an oxygen-precovered, stepped Cu(1 1 25) surface are investigated by scanning tunneling microscopy, low-energy electron diffraction, and magneto-optical Kerr effect analysis. It is concluded from the study that oxygen adsorption strongly affects the structure and spin-reorientation transition of Fe films.

A simple complex-surfactant-assisted hydrothermal reduction process was developed to synthesize copper nanowires with average diameters of ~85 nm and lengths of several tens of micrometers. Results reveal that the surfactant sodium dodecyl benzenesulfonate (SDBS) played a significant role on the copper nanowires growth and the concentrations of NAOH, and glycerol also had significant effects in finding the morphology of the final product.

The molecular structure of small Cu (sub x) S (sub y)(super -) anionic clusters was studied by the combination of ab initio and atom-in-molecules (AIM) calculations. The results stated that covalent Cu-Cu bonding was weak, unstable and not realized even when the intratomic distances were found to be within normal Cu-Cu bond range.

The structure of the heme a(sub 3)-C (triple bond) N-Cu(sub B) complex of the oxidized cytochrome aa(sub 3) oxidase is studied. The resonance Raman and FTIR spectroscopies are used to discuss the properties of the complex.

Copper is underpotentially deposited on electrochemically roughened Au(111) by using the applications of self-assembled monolayers (SAMs). The characteristics of autopolymerizaion and electropolymerization are studied.

A multitechnique [electron paramagnetic resonance (EPR), XANES, EXAFS and IR of absorbed NO] study of the coordination and oxidation chemistry of copper species hosted in mordenite (MOR) zeolite under different conditions is presented. The differences observed between these two systems are explained in terms of the different structural characteristics.

A theoretical density functional study of the exchange coupling in hexanuclear polysiloxanolato-bridged complexes of Cu(II) and Ni(II) is presented. The study shows that by calculating the energies of three different spin configurations, one can obtain estimates of the first, second and third-neighbor exchange coupling constants.

The structure of Copper(II) complex formed within the course of a stereoselective Diels-Alder reaction was investigated by EXAFS, CW-EPR at X- and W-band, HYSCORE, pulsed ENDOR, and UV-vis spectroscopy. The experimental techniques indicate that the chiral bis(sulfoximine) ligand (S,S)-1 and the dienophile forma tetragonally distorted complex in CH2Cl2.

The formation of a series of Xe-CuEtiol [Cu(II) etioporphyrin I] complexes on Cu(001) surface was identified by scanning tunneling microscopy (STM) at cryogenic condition. The structural parameters obtained through STM complement results from spectroscopic studies of van der Waals complexes.

Polymer-protected Cu/Pd bimetallic nanoclusters colloidally dispersed in a glycol solution are investigated by means of extended X-ray absorption fine structure (EXAFS). Cu/Pd alloy structures are observed in a wide range of Cu/Pd composition.

Absorption and laser-induced fluorescence spectra of copper dibromide in a solid neon matrix are described. The high-resolution matrix study provides detailed information about the copper halide electronics states and their vibrational structures.

The adsorption of 4-picoline (4-methylpyridine) on the Cu(110) surface is examined with the help of time-of-flight electron stimulated desorption ion angular distribution (TOF-ESDIAD) and other methods. TOF-ESDIAD is used for the first time to image different structural regions of a chemisorbed molecule, which has been separately labeled with H and D atoms.

A combination of framework-builder (Cu(II) ion and 4,4'-bipyridine (4,4'-bpy) ligand) and framework-regulator (AF6 type anions; A = Si, Ge, and P) provide a series of novel porous coordination polymers. The findings imply that the 4,4'bpy - bridged porous coordination polymers are suitable for the construction of not only the second-generation compounds but also the third generation compounds.

The Dipic:Py pair is presented in the context of duplex DNA with base pairing parameters. The study demonstrates that metal coordination can replace hydrogen bonding while preserving helical structure.

A theoretical and computational study of the nitrogen super hyperfine structure in Cu(II) complexes is reported. The results suggest that the small anisotropy in the nitrogen hyperfine parameters is caused by spin polarization of the nitrogen valence shell orbitals.

The structure and coordination of Cu(super +) ion in ferrierite and Cu(super +) in the ZSM-5 zeolite are composed. The results obtained for the Cu(super+) ferrierite system are compared with those previously obtained for the differences in catalytic activity along with an explanation for the differences in catalytic activity are presented.

The magnetic structures of the distorted wolframitetype oxides CuWO(sub 4), CuMoO(sub 4)-III an Cu(Mo(sub 0.25)W(sub 0.75)-O(sub 4) consist of two-dimensional magnetic sheets defined by one suerexchange(Cu-O-Cu) and three super exchange (Cu-O...O-Cu) paths. The findings indicate that the magnetic unit cell is doubled along the a-axis in CuWO(sub 4), along the c-axis in CuMoO(sub 4)-III and along the a- and b-- axes in Cu(Mo(sub 0.25)W(sub 0.75)-O(sub 4).

The use of oxadiazole fragment for the formation of bimetallic complexes, which can incorporate acetate, hydroxide and oxo supporting bridges between the two metals are illustrated. The results show that the seldom-employed oxadiazole ring can be used effectively for generating bimetallic complexes.

A series of Cu complex assembled compounds with stable pillared layer and noninterpenetrated structure were synthesized and measured the adsorption isotherms of N(sub-2), Ar, and CO(sub-2) on these compounds. The microporosity of the compounds was confirmed by N(sub-2), Ar, and CO(sub-2) adsorption.

Voltage-current (V-I) curves are measured in symmetrical metal/[Pr.sub.0.7][Ca.sub.0.3]Mn[O.sub.3]/metal structures with metal like Ag, Cu, Pt, and Au. The results have shown that Cu/[Pr.sub.0.7][Ca.sub.0.3]Mn[O.sub.3]/Cu produces the largest hysteresis loop, yielding an enhanced colossal electroresistance of 227% at a current of 0.5 Angstrom.

The two dimensional copper halides were hydro-thermally synthesized and characterized. Both compounds are constructed from D6R Cu6I6 cores.

Sterically demanding triazapentadiene [N{C (sub3) F (sub 7) C (Dipp) N (sub 2)] H is synthesized in good yield. The findings indicate that [N{C (sub3) F (sub 7) C (Dipp) N (sub 2)] H reacts with copper (I) oxide in acetonitrite leading to [N{C (sub3)F(sub 7)C(Dipp) N}(sub 2)] CuNCCH(sub 3).

An epitaxial growth technique is applied in order to improve the uniaxial magnetic anisotropy K(sub u)(super grain) of c-plane-oriented columnar grains for CoCr-based perpendicular recording media. It is observed that in the media with a high concentration of B or Cr, the thermal stability was improved mainly due to an increase of K(sub u)(super grain) rather than an enlargement of activation volume (V (sub act)).

The postannealing effects on the magnetic and structural properties of CoCrPt perpendicular films are investigated. The results indicate that the interdiffusion of Cr and Mn into the film through the grain boundaries during annealing decoupled the grains, which improves the magnetic properties.

A semiclassical model of the spin momentum transfer in ferromagnetic film (FM)/normal metal (NM) structures is described. The experimental results are explained by assuming that the Cu/Pt interface acted as a perfect spin sink and hence the increase in the Gilbert damping is described by the maximum strength of spin pumping in Cu.

A new method is described for phthalocyanine (Pc) structural diversity and the incorporation of a functional group that has allowed the fabrication of solvent resistant Pc nanostructures formed by using a newly developed nanoimprint by melt processing (NIMP) technique, a variant of standard nanoimprint lithography (NIL). Copper(I)-catalyzed azide-alkyne cycloaddition (CuAAC), a click chemistry reaction, is used as an approach to structural diversity in Pc marcocycles.

The large-scale molecular-dynamics simulations of dynamic deformation under biaxial tensile strain of prestrained single-crystalline nanometer-scale-thick face-centered cubic (fcc) copper films are described. The results have shown that stacking faults have played a major role in the dissociation, cross slip and eventual annihilation of dislocations in small-volume structures of fcc metals.

An efficient method is described for preparing N-substituted 2H-1,4-benzoxazine-3-(4H)-ones from 2-halophenols via a nucleophilic substitution with 2-chloroacetamides followed by a CuI-catalyzed coupling cyclization. The method has involved simple reaction conditions, a short reaction time, and a broad substrate scope and it is useful for the efficient preparation of biologically and medicinally interesting molecules.

An efficient method is developed for preparing various substituted 2-mercapto benzimidazoles from their corresponding thioureas. 2-Mercapto benzimidazoles substituted with a p-methoxybenzyl group has allowed access to benzimidazole thiones.

A copper-catalyzed process is developed for the N-arylation reaction under very mild conditions in the absence of additional ligand. This protocol has not only tolerated an array of thermally sensitive functional groups, but has also achieved high chemoselectivity.

The nitrogen/bromine sources of 4-TsN[H.sub.2] and NBS are used to obtain the regio- and stereoselective aminobromination of [alpha],[beta]-unsaturated ketones catalyzed by copper powder. The method provides an easy route for preparation of vicinal aminohalo derivatives in the presence of 1 mol% catalyst.

The density functional theory and the COSMO continuum solvent model are used to characterize the structure and stability of [[Cu[([H.sub.2]O).sub.n].sup.2+] hydrated clusters as a function of coordination number (4,5 and 6) and cluster size (n=4-18). The results showed that the compact five-coordinate square-pyramidal geometry is more stable than either the four-coordinate or six-coordinate clusters in aqueous phase.