Revealing the Role of d Orbitals of Transition-Metal-Doped Titanium Oxide on High-Efficient Oxygen Reduction

Precise catalysis is critical for the high-quality catalysis industry. However, it remains challenging to fundamentally understand precise catalysis at the atomic orbital level. Herein, we propose a new strategy to unravel the role of specific d orbitals in catalysis. The oxygen reduction reaction (ORR) catalyzed by atomically dispersed Pt/Co-doped Ti$_{1−x}$O$_{2}$ nanosheets (Pt$_{1}$/Co$_{1}$–Ti$_{1−x}$O$_{2}$) is used as a model catalysis. The z-axis d orbitals of Pt/Co–Ti realms dominate the O$_{2}$ adsorption, thus triggering ORR. In light of orbital-resolved analysis, Pt$_{1}$/Co$_{1}$–Ti$_{1−x}$O$_{2}$ is experimentally fabricated, and the excellent ORR catalytic performance is further demonstrated. Further analysis reveals that the superior ORR performance of Pt$_{1}$–Ti$_{1−x}$O2 to Co$_{1}$–Ti$_{1−x}$O$_{2}$ is ascribed to stronger activation of Ti by Pt than Co via the d–d hybridization. Overall, this work provides a useful tool to understand the underlying catalytic mechanisms at the atomic orbital level and opens new opportunities for precise catalyst design

Where Brain, Body and World Collide

The production cross section of electrons from semileptonic decays of beauty hadrons was measured at mid-rapidity (|y| < 0.8) in the transverse momentum range 1 < pt < 8 Gev/c with the ALICE experiment at the CERN LHC in pp collisions at a center of mass energy sqrt{s} = 7 TeV using an integrated luminosity of 2.2 nb^{-1}. Electrons from beauty hadron decays were selected based on the displacement of the decay vertex from the collision vertex. A perturbative QCD calculation agrees with the measurement within uncertainties. The data were extrapolated to the full phase space to determine the total cross section for the production of beauty quark-antiquark pairs

Production of inclusive ϒ(1S) and ϒ(2S) in p–Pb collisions at √sNN = 5.02 TeV

We report on the production of inclusive Υ(1S) and Υ(2S) in p-Pb collisions at sNN−−−√=5.02 TeV at the LHC. The measurement is performed with the ALICE detector at backward (−4.46<ycms<−2.96) and forward (2.03<ycms<3.53) rapidity down to zero transverse momentum. The production cross sections of the Υ(1S) and Υ(2S) are presented, as well as the nuclear modification factor and the ratio of the forward to backward yields of Υ(1S). A suppression of the inclusive Υ(1S) yield in p-Pb collisions with respect to the yield from pp collisions scaled by the number of binary nucleon-nucleon collisions is observed at forward rapidity but not at backward rapidity. The results are compared to theoretical model calculations including nuclear shadowing or partonic energy loss effects

Exclusive J/ψ\mathrm{J/}\psi photoproduction off protons in ultra-peripheral p-Pb collisions at sNN=5.02\sqrt{s_{\rm NN}}=5.02 TeV

We present the first measurement at the LHC of exclusive J/$\psi$ photoproduction off protons, in ultra-peripheral proton-lead collisions at $\sqrt{s_{\rm NN}}=5.02$ TeV. Events are selected with a dimuon pair produced either in the rapidity interval, in the laboratory frame, 2.5We present the first measurement at the LHC of exclusive J/ψ photoproduction off protons, in ultraperipheral proton-lead collisions at sNN=5.02  TeV. Events are selected with a dimuon pair produced either in the rapidity interval, in the laboratory frame, 2.5<y<4 (p-Pb) or -3.6<y<-2.6 (Pb-p), and no other particles observed in the ALICE acceptance. The measured cross sections σ(γ+p→J/ψ+p) are 33.2±2.2(stat)±3.2(syst)±0.7(theor)  nb in p-Pb and 284±36(stat)-32+27(syst)±26(theor)  nb in Pb-p collisions. We measure this process up to about 700 GeV in the γp center of mass, which is a factor of two larger than the highest energy studied at HERA. The data are consistent with a power law dependence of the J/ψ photoproduction cross section in γp energies from about 20 to 700 GeV, or equivalently, from Bjorken x scaling variable between ∼2×10-2 and ∼2×10-5, thus indicating no significant change in the gluon density behavior of the proton between HERA and LHC energies.We present the first measurement at the LHC of exclusive J/\psi$photoproduction off protons, in ultra-peripheral proton-lead collisions at$\sqrt{s_{\rm NN}}=5.02$TeV. Events are selected with a dimuon pair produced either in the rapidity interval, in the laboratory frame,$2.5<y<4$(p-Pb) or$-3.6<y<-2.6$(Pb--p), and no other particles observed in the ALICE acceptance. The measured cross sections$\sigma (\gamma + {\rm p} \rightarrow J/\psi + {\rm p})$are 33.2$\pm$2.2 (stat)$\pm$3.1 (syst)$\pm$0.7 (theo) nb in p-Pb and 284$\pm$36 (stat)$^{+27}_{-32}$(syst)$\pm$26 (theo) nb in Pb-p collisions. We measure this process up to about 700 GeV in the$\gamma {\rm p}$centre-of-mass, which is a factor of two larger than the highest energy studied at HERA. The data are consistent with a power law dependence of the$J/\psi$photoproduction cross section in$\gamma {\rm p}$energies from about 20 to 700 GeV, or equivalently, from Bjorken-$x$between$\sim 2\times 10^{-2}$to$\sim 2\times 10^{-5}$, thus indicating no significant change in the gluon density behaviour of the proton between HERA and LHC energies

Measurement of electrons from semileptonic heavy-flavor hadron decays in pp collisions at √s = 2.76 TeV

The pT-differential production cross section of electrons from semileptonic decays of heavy-flavor hadrons has been measured at mid-rapidity in proton-proton collisions at s√=2.76 TeV in the transverse momentum range 0.5 < pT < 12 GeV/c with the ALICE detector at the LHC. The analysis was performed using minimum bias events and events triggered by the electromagnetic calorimeter. Predictions from perturbative QCD calculations agree with the data within the theoretical and experimental uncertainties

Production of inclusive ϒ(1S) and ϒ(2S) in p–Pb collisions at sNN=5.02\sqrt{s_{\rm NN}} = 5.02 TeV

We report on the production of inclusive ϒ (1S) and ϒ (2S) in p–Pb collisions at sNN=5.02 TeV at the LHC. The measurement is performed with the ALICE detector at backward ( −4.46<ycms<−2.96 ) and forward ( 2.03<ycms<3.53 ) rapidity down to zero transverse momentum. The production cross sections of the ϒ (1S) and ϒ (2S) are presented, as well as the nuclear modification factor and the ratio of the forward to backward yields of ϒ (1S). A suppression of the inclusive ϒ (1S) yield in p–Pb collisions with respect to the yield from pp collisions scaled by the number of binary nucleon–nucleon collisions is observed at forward rapidity but not at backward rapidity. The results are compared to theoretical model calculations including nuclear shadowing or partonic energy loss effects