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Construction of strong interactions between oxides is compelling for modulating the active sites towards acidic oxygen evolution reaction (OER) electrocatalysts. Here, a solid solution oxide electrocatalyst constructed by alloying of IrO 2 and CrO 2 (labeled as Ir 0.3 Cr 0.7 O 2) is reported with an overpotential of 255 mV at a current density of 10 mA cm−2 for OER in 0.5 M H 2 SO 4 solution, which is much lower than that of the state-of-the-art IrO 2 (357 mV). The mass activity at 1.50 V vs. RHE is 47 folds than that of IrO 2 , and it can maintain such OER stability for more than 200 h. Detailed analysis concludes that the organic ligands-assisted synthesis of Ir 0.3 Cr 0.7 O 2 can enlarge the surface-active area and provide more active sites for water oxidation, while the leaching of Cr and its strong interaction with Ir sites resulting in the formation of high chemical state oxides of Ir with superior activity for acidic OER. It is found that the significantly increasement of oxygen vacancies content during electrochemical test together with the two points mentioned above jointly promote the water oxidation activities of Ir 0.3 Cr 0.7 O 2 electrocatalyst in acidic media. Ir 0.3 Cr 0.7 O 2 solid solution oxides with nanosphere packing morphology exhibit outstanding electrocatalytic activity and ultralong stability (over 200 h) for efficient oxygen evolution in acidic media. [Display omitted] • Ir 0.3 Cr 0.7 O 2 solid solution oxide catalyst is rationally designed and synthesized. • Ir 0.3 Cr 0.7 O 2 exhibits stable and remarkable behaviors for acidic water oxidation. • Ir 0.3 Cr 0.7 O 2 realizes η 10 at 255 mV and OER stability within 200 h in 0.5 M H 2 SO 4. [ABSTRACT FROM AUTHOR]

• The catalytic performance of Ni loaded on different supports was studied. • The Ni/Al 0.5 Ce 0.5 O x catalysts exhibited high catalytic activity. • The introduction of Ce reduced the energy barrier of N associative decomposition. • A potential low-cost approach for NH 3 partial cracking was provided. Partial cracking is a feasible strategy to improve ammonia (NH 3) combustion. The nickel (Ni) based catalysts have become promising non-noble metal NH 3 decomposition catalysts owing to the low cost and decent performance. In order to meet the demand of reducing cost and expanding production, a batch of Ni catalysts were obtained by using low-cost supports and traditional impregnation preparation method. It was found that the Al 2 O 3 was the optimal support for Ni catalysts by comparing the catalytic performance. On the basis of Ni/Al 2 O 3 catalysts, the catalytic activity was further improved by introducing cerium (Ce) modification. The catalytic performance of Ce-doped catalysts enhanced at first and then decreased with the rise of Ce contents. Among all of catalysts in this work, the Ni/Al 0.5 Ce 0.5 O x catalysts possessed the highest activity and the lowest apparent activation energy. The characterization results suggested that the addition of Ce could destroy the pore structure of Al 2 O 3 supports, but it might promote the formation of more B5 active sites. The NH 3 temperature programmed desorption (NH 3 -TPD) results implied that the introduction of Ce strengthened the strong interactions between meatal and support, which improved the activity and stability of the Ce-doped catalysts. The Ni/Al 0.5 Ce 0.5 O x catalysts were proved to possess excellent resistance to the high temperature sintering through the 32 h's thermal stability test. This study provides a feasible path for preparing low-cost Ni catalysts for NH 3 decomposition. [ABSTRACT FROM AUTHOR]

A key challenge for isopropanol fuel cell is to find efficient catalyst for the catalytic ability improvement of isopropanol electro-oxidation reaction. Here, we anchor Pt nanoparticles on the Ni 2 P/resin carbon (RC) to form a Pt–Ni 2 P/RC assembly. Strong interactions at Ni 2 P–Pt interface induce the Ni 2 P to donate electrons to stabilize Pt, thus effectively decreasing the adsorbed energy of isopropanol. As a result, Pt–Ni 2 P/RC exhibits much higher mass activity and better stability than those of Pt/RC and Pt/C. When assembled into a direct isopropanol fuel cell, Pt–Ni 2 P/RC shows a peak power density of 0.095 W cm−2, which is 31.9% greater than that of Pt/C catalyst. Our results offer a new strategy to stabilize Pt by an electron donor for developing affordable direct isopropanol fuel cells. Image 1 • A facile and effective method to synthesize Pt–Ni 2 P/RC nanocomposite. • Pt–Ni 2 P/RC is an active and stable isopropanol electro-oxidation catalyst. • Mass activity of Pt–Ni 2 P/RC is 1.90 times higher compared to Pt/C. • Direct isopropanol fuel cell with Pt–Ni 2 P/RC generates a high power density. [ABSTRACT FROM AUTHOR]

Abstract We study the interaction of scalar glueball with quark–antiquark and four-quark spinless meson fields within the framework of a generalized linear sigma model in which the trace anomaly of QCD is exactly realized. To determine the pure scalar glueball mass (m h), we consider the decoupling limit in which the scalar glueball decouples from the meson fields. We find the exact relationship m h = 2 h 0 where h 0 is the vacuum expectation value of the scalar glueball field independent of the properties of the framework used. [ABSTRACT FROM AUTHOR]

Phase transitions in a non-perturbative regime can be studied by ab initio Lattice Field Theory methods. The status and future research directions for LFT investigations of Quantum Chromo-Dynamics under extreme conditions are reviewed, including properties of hadrons and of the hypothesized QCD axion as inferred from QCD topology in different phases. We discuss phase transitions in strong interactions in an extended parameter space, and the possibility of model building for Dark Matter and Electro-Weak Symmetry Breaking. Methodological challenges are addressed as well, including new developments in Artificial Intelligence geared towards the identification of different phases and transitions. [ABSTRACT FROM AUTHOR]

Recently, the ZrO 2 -based catalysts for PDH exhibited high activity owing to the formation of oxygen vacancy and coordinatively unsaturated Zr (Zr cu) sites. However, industrial C 3 H 8 raw gases typically contain trace amounts of oxygen at 10–1000 ppm, which can significantly decrease the PDH activity of nano-sized ZrO 2 catalyst, because that oxygen vacancy can be filled by the O 2 molecules rapidly, while the rate of lattice oxygen consumption is relatively slow. Here, highly dispersed NiO x species loading on ZrO 2 significantly increased C 3 H 6 formation rate (up to 6.6 times) and decreased the activation energy. The strong interaction between NiO x species and ZrO 2 enhances the ability of ZrO 2 to release its lattice oxygen, and increases the concentration of oxygen vacancy and unsaturated Zr-O acid-base pairs for PDH. This strategy can expand to other metal oxides interacted with ZrO 2 to eliminate the inhibiting effect of trace oxygen, such as GaO x , CoO x , CrO x , LaO x , and InO x. [Display omitted] • A trace O 2 in C 3 H 8 /N 2 feed gas can significantly decrease the PDH activity of nano-sized ZrO 2 catalyst. • Highly dispersed NiO x species loading on ZrO 2 significantly increased C 3 H 6 formation rate under oxygen-lean PDH condition. • The strong interaction between NiO x and ZrO 2 enhances the ability of ZrO 2 to release lattice oxygen and and form oxygen vacancy. [ABSTRACT FROM AUTHOR]

The exploitation of efficient OER electrocatalysts has become the key to realize the commercial-application of H 2 production from electrocatalytic water splitting. In this research, the novel defect-induced N, S co-doped carbon-supported Co 3 C nanoparticles were successfully fabricated as OER electrocatalyst by combination of wet-impregnation treatment of Co/sulfonated polybenzimidazole (sPBI) and subsequent thermal annealing treatment, which was denoted as Co 3 C/CNS-X (X=700, 800, 900) electrocatalyst. Among them, Co 3 C/CNS-800 delivered the more favorable architecture due to its large specific surface area, high dispersion of Co 3 C nanoparticles and especially the generation of abundant defects sites, which not only improved its conductivity and the amounts of electrocatalytically active sites but also imparted the extremely important functionality in accelerating the interfacial electron-transfer and facilitated the adsorption ability of intermediates, thus exerting the extraordinary activities for catalyzing OER. What's more, there were some evidences demonstrating the generation of the strong interfacial interactions through the Co-N coordination bonds and the formation of more pyridinic-N species though annealing treatment, which allowed the structural stability to be further strengthened and simultaneously gave impetus to the O 2 release for the reduction of OER overpotential. In recognition of these approvable structural characteristics, the Co 3 C/CNS-800 exhibited the lowest overpotential of 300 mV at an anodic current density of 10 mA cm−2, and a small Tafel slope of 70 mV dec−1 in 1 M KOH electrolyte as well as a long durability. [Display omitted] [ABSTRACT FROM AUTHOR]

We consider a generalization of the Standard Model whose action displays conformal invariance in d dimensions. The model contains a strongly coupled dark matter sector which breaks conformal symmetry dynamically. The model evades conformal anomaly and leads to identically zero vacuum energy in flat space-time. Hence it does not suffer from the problem of fine tuning of the cosmological constant. We determine the contribution of non-relativistic matter to the energy-momentum tensor and determine a parameter regime in which it approximately reduces to the standard result. We show how dark energy and dark matter arises in this model. We discuss the parameter range for which the model reduces to the Λ CDM model and hence is consistent with observations. [ABSTRACT FROM AUTHOR]

Abstract: Recent progress in hadron structure calculations within lattice QCD is reviewed. Results on key observables such as the axial charge, the quark momentum fraction and the spin content of the nucleon are discussed with focus on open issues. Lattice QCD studies of the transition as well as the form factors are also presented. [Copyright &y& Elsevier]

Abstract: Commonly used techniques to study non-perturbative aspects of the strong interactions have a deep connection with rational approximants, and in particular with Padé approximants to meromorphic functions. However, only recently this connection has been acknowledged and efforts at fully exploiting it are only starting. In this article I will briefly review the most prominent techniques used in non-perturbative strong interactions with special emphasis on its relation with Padé approximants. I will then concentrate on a set of open problems outside the scope of these conventional techniques where Padé approximants might be extremely useful. [ABSTRACT FROM AUTHOR]

Abstract: A heavy fourth family is an example of new physics which is well defined and familiar in some respects, but which nevertheless has radical implications. In particular it eliminates a light Higgs description of electroweak symmetry breaking. We discuss an early signal for heavy quarks at the LHC in the form of an excess of “W-jets”, and as well show how W-jets may be useful in the reconstruction of the heavy quark masses. We argue that fourth family quarks can be distinguished from vector-like quarks of a similar mass at roughly the same time that a same sign lepton signal becomes visible. Given the large mass of the fourth neutrino we describe how a picture for neutrino mass emerges in the absence of right-handed neutrinos, and how it suggests the existence of a remnant flavor gauge symmetry. [Copyright &y& Elsevier]

Abstract: We study the structure of the confining string in Yang–Mills theory using the method of the field strength correlators. The method allows us to demonstrate that both the local fluctuations of the topological charge and the gluon condensate are suppressed in the vicinity of the string axis in agreement with results of lattice simulations. [Copyright &y& Elsevier]

• The assembly of ultrathin CoOOH nanosheets into the PANI network can be realized as OER catalyst. • The nitrogen species derived from PANI can work as bridging sites to coordinate with Co metal ions. • The electron delocalization of Co/PANI HNSs can regulate its own electronic structural states. • The Co/PANI HNSs presents a hierarchical porous with both structure of mesopores and macropores. • The high-stability Co/PANI HNSs catalyst can afford a low overpotential with a small Tafel slope. Polyaniline (PANI)-based composite materials have shown to be promising candidates for oxygen evolution reaction (OER) electrocatalysts because of their non-ignorable merits of conductivity, flexibility, durability and environmental friendly. Herein, we develop a facile strategy to realize in-situ assembly of CoOOH nanosheets into the PANI network, which is denoted as Co/PANI HNSs for OER performance. The nitrogen species derived from PANI building blocks can work as bridging sites to preferentially coordinate with Co metal ions, which impart coupling effects between CoOOH nanosheets and PANI as well as the structure stability. Besides the Co-N coordination, the occurred electron delocalization between Co d-orbitals and PANI π-conjugated ligands can also modulate the electronic structural states of Co/PANI HNSs, enabling the efficient interfacial electron transfer from CoOOH to PANI. In addition, the Co/PANI HNSs possesses a hierarchical porous with both structure of mesopores and macropores that allows electrolyte to be more efficiently transported to the highly oxidative active sites, resulting in fast reaction kinetics. In recognition of these advanced structural characteristics, the Co/PANI HNSs electrocatalyst can give a low overpotential of 291 mV at an anodic current density of 10 mA cm−2 and a small Tafel slope of 54 mV dec−1 in 1 M KOH electrolyte as well as a good durability. [ABSTRACT FROM AUTHOR]

• The Co 3 O 4 /CN HNPs is successfully fabricated as high-efficiency OER electrocatalyst. • The Co 3 O 4 /CN HNPs has the advantages of high conductivity and exposed active sites. • The formation of Co-N bonds is instrumental in strengthening structural stability. • The existence of defects over Co 3 O 4 nanoparticles is favorable for OER kinetics. • The Co 3 O 4 /CN HNPs presents excellent OER performance and unprecedented stability. The development of earth-abundance electrocatalyst with high performance for oxygen evolution reaction (OER) is of paramount importance in sustainable water splitting. Herein, the novel defect-induced nitrogen-doped carbon-supported Co 3 O 4 nanoparticles is successfully fabricated as OER electrocatalyst (denoted as Co 3 O 4 /CN HNPs) through a wetness-impregnation treatment of Co/polyaniline (PANI) followed by a thermal annealing. This advanced architecture of Co 3 O 4 /CN HNPs can not only improve its conductivity and electrocatalytically active sites but also generate a large number of oxygen-vacancy defects and crystal defects, which effectively exert the preponderance in facilitating interfacial electronic transfer and optimizing the adsorption energy for intermediates, thus imparting the extraordinary activities in catalyzing OER. In addition, there are evidences demonstrating the formation of C-N coordination bonds through the strong interaction of the interconnected interface and the generation of pyridinic-N species after the annealing treatment, which enables the structural stability to get further strengthened and accelerates oxygen releasing for reduction of OER overpotential, respectively. Benefiting from the above desirable properties, the Co 3 O 4 /CN HNPs affords a lower overpotential of 290 mV at a current density of 10 mA cm−2 as compared to those of pure Co 3 O 4 and PANI, outperforming commercial IrO 2 and the representative Co 3 O 4 -based OER electrocatalysts as recently reported. Moreover, the Co 3 O 4 /CN HNPs also exhibits long durability with negligible activity degeneration at a current density of 10 mA cm−2 for 20 h. ̵. [ABSTRACT FROM AUTHOR]