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Developing a theoretical framework for conducting electronic fluids qualitatively distinct from those described by Landau's Fermi-liquid theory is of central importance to many outstanding problems in condensed matter physics. One such problem is that, above the transition temperature and near optimal doping, high-transition-temperature copper-oxide superconductors exhibit 'strange metal' behaviour that is inconsistent with being a traditional Landau Fermi liquid. Indeed, a microscopic theory of a strange-metal quantum phase could shed new light on the interesting low-temperature behaviour in the pseudogap regime and on the d-wave superconductor itself. Here we present a theory for a specific example of a strange metal--the 'd-wave metal'. Using variational wavefunctions, gauge theoretic arguments, and ultimately large-scale density matrix renormalization group calculations, we show that this remarkable quantum phase is the ground state of a reasonable microscopic Hamiltonian--the usual t-J model with electron kinetic energy t and two-spin exchange J supplemented with a frustrated electron 'ring-exchange' term, which we here examine extensively on the square lattice two-leg ladder. These findings constitute an explicit theoretical example of a genuine non-Fermi-liquid metal existing as the ground state of a realistic model., Over the past several decades, experiments on strongly correlated materials have routinely revealed, in certain parts of the phase diagram, conducting liquids with physical properties that are qualitatively inconsistent with [...]

This work reported for the first time the anodic electrochemiluminescence (ECL) of CdTe quantum dots (QDs) in aqueous system and its analytical application based on the ECL energy transfer to analytes. The CdTe QDs were modified with mercaptopropionic acid to obtain water-soluble QDs and stable and intensive anodic ECL emission with a peak value at + 1.17 V (vs Ag/AgCl) in pH 9.3 PBS at an indium tin oxide (ITO) electrode. The ECL emission was demonstrated to involve the participation of superoxide ion produced at the ITO surface, which could inject an electron into the 1Se quantum-confined orbital of CdTe to form QDs anions. The collision between these anions and the oxidation products of QDs led to the formation of the excited state of QDs and ECL emission. The ECL energy transfer from the excited CdTe QDs to quencher produced a novel methodology for detection of catechol derivatives. Using dopamine and L-adrenalin as model analytes, this ECL method showed wide linear ranges from 50 nM to 5 [micro]M and 80 nM to 30 [micro]M for these species. Both ascorbic acid and uric acid, which are common interferences, did not interfere with the detection of catechol derivatives in practical biological samples.

Discussing a quantitative study of the microstructure and critical current density of Nb-Ti superconductors that is produced with a varying combination of deformation intervals between anneals is presented. The TEM was used to quantitatively evaluate the degree of diffusional decomposition in a supersaturated solid solution at different stages of alloy statement.

Discussing the dependence of quench characteristics of HTS tapes on the amplitude of current and duration time is investigated by applying alternating current (AC) that is several times over the critical currents of HTS tapes is presented. Analyzing the quench development using voltage-current characteristics and examined the influence of pitch angles on resistance increase.

The study conducted shows that optimizing the rolling conditions and heat treatment temperature and time results in the formation of Ni substrate with sharp cube texture is discussed. The cube texture is promoted by recrystallization after cold rolling is concluded.

Students of general chemistry should understand that the concept of electronegativity (EN) is valuable as a tool for explaining many of the trends seen in chemistry, but that it has its limitations. EN difference is shown to be an improper function for separating ionic from covalent bonding. Pauling defined electronegativity as the power of an atom to attract electrons in a molecule. Metallic bonding can be included whenever electronegativity values and bonding characteristics are compared, and it should be included.

The article discusses research into the relationship between ligands and metal based on computational and optical absorption studies.

The reactive 3Fe cluster in the 7Fe ferredoxin from Desulfovibrio africanus, incorporating Fe and other metals to to form cubanes (M3Fe-4S) has a non-cystein ligation to the added metal (M). Connectivities among interconversion with different M, the influence of pH and the reactivities of certain cluster oxidation levels have been studied using electrochemical and spectroscopic methods.

Studies of homogeneous catalytic process in aqueous solutions have been extended to investigate other systems involving compounds of the group 10 metals. P(CHsub2OH)sub3, a water-soluble phosphine ligand was used to synthesize such metal derivatives. The synthesis and spectroscopic characterization of (Ni(NO)(PTA)sub3)-NOsub3, Ni(PTA)sub4, Pd(PTA)sub4, cis-PdC1sub2(PTA)sub2, (PdC1-(PTA)sub3)C1, Pt(PTA)sub4 and cis-PtC1sub2(PTA)sub2 is described.

Charge-carrier injection and transport have been studied in relation to light-emitting diodes based on poly-p-phenylene-vinylene (PPV). It was found that thermal conversion of the prepolymer on indium-tin-oxide (ITO) substrates leads to a p-type doping of PPV. It leads also to formation of an ohmic hole-injecting contact at the ITO/PPV interface. This is not like conversion on Au and other high-work-function metals. Devices made with low-work-function metals as the electron injecting contact display Schottky behavior, act as Schottky diodes, distinguished by a high rectification ratio and display electrolumiescence at bias voltages as low as 1.5 V for ITO/PPV/Ca light-emitting diodes.

Metal-assisted cycloaddition reactions are very useful in the synthesis of organic and organometal compounds, with the metal fragment having a number of roles. A metal complex and organic substrate firstly react in a stoichiometric way to yield the compound with which the metal-assisted cycloaddition reaction can begin. The sterical and electronic properties of a metal influence the reaction where the metal is bound to one or more of the starting materials. Metal-assisted cycloaddition reactions are analysed, including (2+1), (2+2), (3+2), (4+2) reactions, together with higher order and multicomponent metal-assisted cycloaddition reactions.

A simple experimental method for measuring the anomalous skin depth and Fermi velocity in metals is presented. The skin depth is evaluated by measuring the resistance at 77 K of a thick metal wire specimen at frequencies of 100 Hz and 0.1 MHz. The Fermi velocity is obtained by using the theoretical expression that relates the anomalous skin depth to the Fermi velocity.