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This paper provides an overview of recent advances in urea electro-oxidation. Urea sources are abundant from human urine, urea-containing wastewater, and industrial urea, thus becoming an attractive option as anodic fuel for the application in direct urea fuel cells (DUFCs). Besides, as a hydrogen-rich chemical fuel, urea can also be electrolyzed to produce hydrogen for energy storage in the near future. The exact mechanisms of urea decomposition are pretty different in alkaline or neutral mediums and are separately discussed in detail. More importantly, the development of anodic electro-catalysts is of great significance for improving the electrochemical performance of both DUFCs and urea electrolysis cells, which is systematically summarized in our review. Challenges and prospects on the future development of urea electro-oxidation are particularly proposed.

Unique nanostructure, high electrical conductivity, satisfactory energy density, and extraordinary cycling stability are important evaluation criteria for high-efficient energy storage devices. Herein, Fe

Flexible supercapacitor plays a progressively more important part in power source for smart electronic devices and how to enhance its energy density is the urgent issue to be addressed. Hence, a hybrid electrode of Polypyrrole@reduced graphene oxide hydrogel (PPy@rGOH) is synthesized via a combine hydrothermal treatment of GO solution to assemble hydrogel and subsequently in-situ electropolymerization preparation of PPy on the surface of graphene. Through controlling the time of electropolymerization, the resultant PPy@rGOH-20 s with high specific surface area exhibits an excellent specific capacitance of 340 F g−1 at a current density of 1 A g−1 and superior cycling stability of 87.4% capacitance retention after 10,000 charging/discharging cycles at 3 A g−1 in 1 M KNO3. The assembled flexible asymmetric supercapacitor (FASC) by employing the PPy@rGOH-20s as positive electrode and pure rGOH as negative electrode presents a maximum operational voltage window of 1.6 V and high energy density of 46.9 W h kg−1, which is higher than polymer/carbon-based supercapacitors previously reported.

The Grassmannian of affine subspaces is a natural generalization of both the Euclidean space, points being zero-dimensional affine subspaces, and the usual Grassmannian, linear subspaces being special cases of affine subspaces. We show that, like the Grassmannian, the affine Grassmannian has rich geometrical and topological properties: It has the structure of a homogeneous space, a differential manifold, an algebraic variety, a vector bundle, a classifying space, among many more structures; furthermore; it affords an analogue of Schubert calculus and its (co)homology and homotopy groups may be readily determined. On the other hand, like the Euclidean space, the affine Grassmannian serves as a concrete computational platform on which various distances, metrics, probability densities may be explicitly defined and computed via numerical linear algebra. Moreover, many standard problems in machine learning and statistics --- linear regression, errors-in-variables regression, principal components analysis, support vector machines, or more generally any problem that seeks linear relations among variables that either best represent them or separate them into components --- may be naturally formulated as problems on the affine Grassmannian., 25 pages, 1 figure. This article contains material in earlier versions of arXiv:1607.01833, which has been split into two parts at an editor's recommendation

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We have designed and constructed a portable extruder with a rotatable mandrel, which can be employed to study the multi-dimensional flow field (MDFF) induced crystallization of polymer combined with in situ wide angle x-ray scattering (WAXS). With the piston driving the melt sample to flow along the channel, a direct axial shear field is achieved. At the same time, the central mandrel keeps rotating under a stable speed, providing the sample with an additional circumferential shear field. By presetting different proportions of the two shear fields, namely, axial and circumferential, various flow states of the sample can be obtained, which makes it capable of investigating the effects of MDFF on polymer crystallization. We have performed an in situ WAXS experiment of MDFF induced crystallization of isotactic polypropylene based on the portable extruder at the beam line BL16B in Shanghai Synchrotron Radiation Facility. The rheological and structural information is collected simultaneously, which manifests the viability of the portable extruder on regulating MDFF and can provide guidance for polymer processing.

We study S-duality of Argyres-Douglas theories obtained by compactification of 6d (2,0) theories of ADE type on a sphere with irregular punctures. The weakly coupled descriptions are given by the degeneration limit of auxiliary Riemann sphere with marked points, among which three punctured sphere represents isolated superconformal theories. We also discuss twisted irregular punctures and their S-duality., Comment: 56 pages, 13 figures

In this paper, we show the equivalence between two seemingly distinct 2d TQFTs: one comes from the "Coulomb branch index" of the class S theory $T[\Sigma,G]$ on $L(k,1) \times S^1$, the other is the $^LG$ "equivariant Verlinde formula", or equivalently partition function of $^LG_{\mathbb{C}}$ complex Chern-Simons theory on $\Sigma\times S^1$. We first derive this equivalence using the M-theory geometry and show that the gauge groups appearing on the two sides are naturally $G$ and its Langlands dual $^LG$. When $G$ is not simply-connected, we provide a recipe of computing the index of $T[\Sigma,G]$ as summation over indices of $T[\Sigma,\tilde{G}]$ with non-trivial background 't Hooft fluxes, where $\tilde{G}$ is the simply-connected group with the same Lie algebra. Then we check explicitly this relation between the Coulomb index and the equivariant Verlinde formula for $G=SU(2)$ or $SO(3)$. In the end, as an application of this newly found relation, we consider the more general case where $G$ is $SU(N)$ or $PSU(N)$ and show that equivariant Verlinde algebra can be derived using field theory via (generalized) Argyres-Seiberg duality. We also attach a Mathematica notebook that can be used to compute the $SU(3)$ equivariant Verlinde coefficients., Comment: 40 pages, 7 figures, Mathematica Notebook attached; v2: misprints corrected; v3: Acknowledgement added, corrections made based on the journal version

We use Coulomb branch indices of Argyres-Douglas theories on $S^1 \times L(k,1)$ to quantize moduli spaces ${\cal M}_H$ of wild/irregular Hitchin systems. In particular, we obtain formulae for the "wild Hitchin characters" -- the graded dimensions of the Hilbert spaces from quantization -- for four infinite families of ${\cal M}_H$, giving access to many interesting geometric and topological data of these moduli spaces. We observe that the wild Hitchin characters can always be written as a sum over fixed points in ${\cal M}_H$ under the $U(1)$ Hitchin action, and a limit of them can be identified with matrix elements of the modular transform $ST^kS$ in certain two-dimensional chiral algebras. Although naturally fitting into the geometric Langlands program, the appearance of chiral algebras, which was known previously to be associated with Schur operators but not Coulomb branch operators, is somewhat surprising., 47+20 pages, 3 figures. v2: reference added, misprints corrected. v3: added corrections according to journal referee

We show how the Riemannian distance on $\mathbb{S}^n_{++}$, the cone of $n\times n$ real symmetric or complex Hermitian positive definite matrices, may be used to naturally define a distance between two such matrices of different dimensions. Given that $\mathbb{S}^n_{++}$ also parameterizes $n$-dimensional ellipsoids, and inner products on $\mathbb{R}^n$, $n \times n$ covariance matrices of nondegenerate probability distributions, this gives us a natural way to define a geometric distance between a pair of such objects of different dimensions., Comment: 9 pages

Paederia scandens has been used as a traditional medicine in Asian countries to treat jaundice, dysentery, and the pain of rheumatism. The complete chloroplast (cp) genome sequence of P. scandens w...

Herein, Polypyrrole was used as the conductive wrapping material electro-deposited on the MnO 2 nanoflakes covered on C/TiO 2 nanowire arrays to form PPy@MnO 2 @C/TiO 2 double shell/core structured arrays electrode for supercapacitor. Their structure and surface morphology were studied by using X-ray diffraction analysis, scanning electron microscopy and transmission electron microscopy. The results suggest that a thin layer of PPy was successfully wrapped on the surface of MnO 2 , and the shell/core structure of MnO 2 @C/TiO 2 nanowire arrays was not changed after electro-deposition of PPy. The electrochemical tests indicate that the PPy@MnO 2 @C/TiO 2 double shell/core arrays electrode exhibits high specific capacitance of 715 F g −1 at a charge/discharge current density of 1 A g −1 and improved specific capacitance retention to 84.0% after 1000 cycles. These results show that the unique three dimensional (3D) double shell/core structured electrode holds promise for high-performance energy storage devices. The superior capacitive perfomance may due to the unique 3D C/TiO 2 nanowires and the unique double shell/core structures. Firstly, the 3D C/TiO 2 nanowire arrays, as excellent platform for loading active materials, can facilitate the permeation of electrolyte. Moreover, the thin layer PPy tightly wrapped on the MnO 2 nanoflakes can improve the electrical conductivity of MnO 2 . Therefore, the PPy@MnO 2 @C/TiO 2 electrode is promising candidate for electrochemical energy applications.

M1/3Ni1/3Mn2/3O2 (M = Mg or Zn) is sucessfully synthesize from Na2/3Ni1/3Mn2/3O2 via a electrochemical conversion method. The structure and morphology of the as-prepared material are systematically characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), inductively coupled plasma atomic emission spectroscopy (ICP-AES) and X-ray photoelectron spectroscopy (XPS), respectively. The nano-sized morphology of M1/3Ni1/3Mn2/3O2 is beneficial for the reduction of diffusion length and transfer acceleration of cations from the surface into the bulk interiors. XRD patterns reveal that crystal structure is maintained after the reversible Mg2+ or Zn2+ intercalation/deintercalation. Its performance for Mg2+ and Zn2+ intercalation/deintercalation in aquesous electrolytes is evaluated by cyclic voltammetry, galvanostatic cycling and electrochemical impedance spectroscopy. Mg1/3Ni1/3Mn2/3O2 exhibits an initial capacity of 170.5 mAh g−1 in 1 mol L−1 Mg(NO3)2, Zn1/3Ni1/3Mn2/3O2 displays capacity of 113.7 mAh g−1 in 1 mol L−1 ZnSO4. Mg1/3Ni1/3Mn2/3O2 shows a good cycling performance and maintains 52.7 mAh g−1 at 1.0C after 200 cycles in 1.0 mol L−1 MgSO4.

Pt-modified Co nanosheet@carbon sponge (Pt-Co NS@carbon sponge) electrode is synthesized via a facile sponge carbonization method coupled with a direct Co electrodeposition and Pt chemical-deposition. The obtained electrodes are characterized by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDX) and transmission electron microscopy (TEM). The catalytic performances of H 2 O 2 electroreduction in alkaline medium are investigated by cyclic voltammetry (CV), chronoamperometry (CA) and electrochemical impedance spectroscopy (EIS). The Pt-Co NS@carbon sponge electrode exhibits unique nanosheet structure on the three-dimensional (3D) porous network skeleton with a large surface area and displays excellent catalytic performance. The Pt-Co NS@carbon sponge electrode achieves a reduction current density of −1.38 A cm −2 mg −1 in 3.0 mol L −1 KOH and 1.5 mol L −1 H 2 O 2 at −0.50 V (vs. Ag/AgCl) accompanied with a desirable stability, which is significantly higher than the catalytic activity of H 2 O 2 electroreduction achieved previously with precious metals as catalysts. The impressive electrocatalytic performance is largely attributed to the superior 3D open structure and high electronic conductivity, which ensures the full utilization of Pt surfaces and makes the electrode have higher electrochemical activity. Original Pt-Co NS@carbon sponge electordes have a great potential for the application in fuel cells due to its facile preparation, high performance and low cost.

In this paper, freestanding one-dimensional MnO 2 nanoflakes are successful prepared through a simple hydrothermal reaction by using the carbon shell of TiC/C core/shell arrays as the sacrificial template. Its structure and morphology are characterized by X-ray diffractometer, X-ray photoelectron spectroscopy, Raman spectroscopy, scanning electron microscopy, energy dispersive X-ray spectrometer and transmission electron microscopy. Results show that the thickness of the carbon shell decreased but also remained and the ultrathin MnO 2 nanoflakes with thickness less than 5 nm uniformly grow on the surfaces of the TiC/C nanowire to form a core/double shell structure after the hydrothermal reaction. The electrochemical performance of the as-prepared electrode is evaluated by cyclic voltammetrys, galvanostatic charging-discharging tests and electrochemical impedance spectroscopy, and high capacities, excellent rate capabilities and exemplary cycling performance is obtained. The as-prepared electrode shows a high specific capacitance of 598.8 F g −1 and 85.8% of its initial capacitance is retained after 10,000 cycles at a high discharge current density of 10 A g −1 , suggesting that this structure has a promising future as high-performance supercapacitor electrode.

The southern boundary of the central segment of the Central Asian Orogenic Belt (CAOB) with the Precambrian Alxa Block is not well constrained due to poor recognition of deep crust. Statistical analysis of zircon xenocrysts within igneous rocks from the northern Alxa and its adjacent regions was applied to resolve this problem. We compiled new and previously published geochronological zircon age data obtained by SHRIMP, SIMS, TIMS, and LA-ICP-MS for 316 igneous rock samples of which 61 samples contain zircon xenocrysts. New and previously published Hf isotopic compositions of these zircon xenocrysts are combined with zircon ages in this study. The zircon xenocrysts are mainly contained within Permian rocks from the Yabulai–Nurgong–Honggueryulin (YNH) zone and igneous rocks from the northwestern margin of the North China Craton (WNCC). A few xenocrysts were also found in Permian igneous rocks from the Zongnaishan–Shalazhashan (ZS) zone, Neo-proterozoic and Paleo-proterozoic intrusive rocks in the YNH zone, as well as Devonian to Carboniferous granitoids and volcanic rocks from southern Mongolia. Altogether we analyzed more than 270 zircon xenocrysts and considered only ages that are less than 10% discordant. Xenocryst ages within the Permian igneous rocks from the ZS zone are mainly around ca. 350 Ma, ca. 600 Ma and ca. 1400 Ma. The oldest age of zircon xenocrysts in this zone is similar to those of zircon xenocrysts from the CAOB (∼1.1 Ga). By contrast, abundant zircon xenocrysts within Permian igneous rocks from the YNH zone show highly variable age populations at ca. 2.6–2.1 Ga, 1.8–1.6 Ga, 930–750 Ma and 460–300 Ma. Zircon xenocrysts from the ZS zone have positive eHf(t) values of +6.3 to +13.9, whereas those from the YNH zone display highly variable eHf(t) values from −16.1 to +11.6. From the southern CAOB and the ZS zone to the YNH zone, the zircon xenocrysts show a significant shift from juvenile to crustal Hf isotopic compositions, suggesting that the area between the ZS and the YNH zones constitutes the southern boundary of the CAOB in the deep crust within this region. Our study indicates that statistical analysis (or isotopic mapping) of zircon xenocrysts is an effective method to trace the nature of the deep continental crust and to separate between newly-formed orogenic domain and ancient cratons.

Three dimensional (3D) honeycomb-like NiS 2 /NiO nano-multiple materials were successfully prepared by fabricating cribrate NiS 2 on the surface of NiO nanosheets through simple hydrothermal process on nickel foam. The morphology and phase structure of the NiS 2 /NiO are characterized by scanning electron microscopy equipped with energy dispersive X-ray spectrometer, transmission electron microscope, X-ray diffractometer and the electrochemical properties are tested by cyclic voltammetry, galvanostatic charge/discharge and electrochemical impedance spectroscopy. The NiS 2 /NiO electrode owns lower electrochemical impedance compared with bare NiO substrate and exhibits exceptional capacitance performance with a high specific capacitance of 2251 F g −1 delivered at current density of 1 A g −1 , while 1192 F g −1 retained at 20 A g −1 . What's more, after 2000 cycles, the specific capacitance remains 1275 F g −1 (at 5 A g −1 ) with a capacitance retention of 78%. Therefore, the NiS 2 /NiO electrode shows remarkable electrochemical performance and has a promising future for electrochemical supercapacitors.

OBJECTIVES The present study aimed to evaluate the prognostic value of preoperative carbohydrate antigen 125 (CA125) levels for clinical outcomes after off-pump coronary artery bypass grafting (OPCAB). METHODS A total of 314 consecutive patients who underwent OPCAB were enrolled in this study and divided into three groups corresponding to baseline CA125 level tertiles. Clinical outcomes of these patients were followed up after 1 year. The primary endpoint was the incidence of combined major adverse cardiac events (MACE). RESULTS Event-free survival was significantly associated with the CA125 tertile (log-rank P=0.021); specifically, hazard ratios (HRs) increased progressively from CA125 tertile 1 to tertile 3 [vs. tertile 1: tertile 2 h=1.8; 95% confidence interval (CI): 1.1-2.8, P=0.040; tertile 3 h=2.9; 95% CI: 1.1-8.1, P=0.018]. In the first multivariate Cox regression analytical model (all variables except EuroSCORE), CA125 was an independent predictor of MACE (HR=1.1, 95% CI: 1.0-2.4, P=0.016). In a second model (CA125 levels and EuroSCORE only), CA125 remained an independent predictor of MACE (HR=1.1, 95% CI: 1.0-1.3, P=0.036). CONCLUSION An increased preoperative CA125 level is an independent predictor of worse clinical outcomes after OPCAB during a 1-year follow-up.

Flexible and binder-free multi-walled carbon nanotube (MWNT)-modified sponge-based nickel (Ni) is employed as the electrode material for methanol (CH3OH) electrooxidation. The nano-spherical Ni is electrodeposited on the surface of the MWNTs which are assembled on the skeleton of a commercial sponge. The as-prepared MWNT-modified sponge-based Ni electrode (MSNi) is characterized by scanning electron microscopy, transmission electron microscope, and X-ray diffractometer. The catalytic activity of the MSNi electrode for CH3OH electrooxidation is investigated by means of cyclic voltammetry, chronoamperometry, and electrochemical impedance spectra. The preparation process of the flexible MSNi electrode does not use any binder and it exhibits a unique three-dimensional (3D) network-porous structure. The MSNi exhibits a high electrocatalytic performance of 23 mA (cm2 mg−1) in 0.5 mol dm−3 CH3OH at 0.5 V.

Highly porous nickel@carbon sponge electrode with low cost is synthesized via a facile sponge carbonization method coupled with a direct electrodeposition of Ni. The obtained electrodes are characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDX). The catalytic performances of urea electro-oxidation in alkaline medium are investigated by cyclic voltammetry (CV) and chronoamperometry (CA). The Ni@carbon sponge electrode exhibits three-dimensional open network structures with a large surface area. Remarkably, the Ni@carbon sponge electrode shows much higher electrocatalytic activity and lower onset oxidation potential towards urea electro-oxidation compared to a Ni/Ti flat electrode synthesized by the same procedure. The Ni@carbon sponge electrode achieves an onset oxidation potential of 0.24 V (vs. Ag/AgCl) and a peak current density of 290 mA cm −2 in 5 mol L −1 NaOH and 0.10 mol L −1 urea solutions accompanied with a desirable stability. The impressive electrocatalytic activity is largely attributed to the high intrinsic electronic conductivity, superior porous network structures and rich surface Ni active species, which can largely boost the interfacial electroactive sites and charge transfer rates for urea electro-oxidation in alkaline medium, indicating promising applications in fuel cells.

In this work, Au nanoparticles directly grown on the surface of TiO 2 core-C shell (Au/C@TiO 2 ) has prepared by a simple electrodeposition method for the first time. The morphology is characterized by scanning electron microscope, and its structure is investigated by X-ray diffraction. Au nanoparticles are uniformly distributed on the surface of C@TiO 2 nanowire array. Its catalytic performance for NaBH 4 oxidation is evaluated by cyclic voltammetry and chronoamperometry measurement. The results indicate that Au/C@TiO 2 shows a good and stable catalytic performance. In 2 mol cm −3 NaOH and 0.2 mol cm −3 NaBH 4 the oxidation current density for the electrooxidation of BH 4 − can reach 475 mA cm −2 at 0 V. The electrons transfer number released by BH 4 − electrooxidation on Au/C@TiO 2 electrode has been found to be a 6-electron process. The high performance is mainly attributed to its 3D structure which can promote the mass transport of NaBH 4 , electronic conductivity and Au utilization.

In this paper, the graphene oxide nanosheets are simultaneously reduced and deposited on nickel foam (denoted as Ni-foam@GNS) by one step electrodeposition method. The interconnected crumpled graphene nanosheets grown on Ni foam serve as a three-dimensional (3D) conductive skeleton for hydrothermal deposition of MnO 2 nanosheets by in-situ redox reaction. The MnO 2 nanosheets anchored on the graphene covered nickel foam (denoted as Ni-foam@GNS@MnO 2 ) show unique 3D porous interconnected networks. The samples are characterized by using X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), thermal gravimetric analysis (TGA), N 2 adsorption–desorption measurements and fourier transform infrared spectroscopy (FT-IR). The capacitive performances are researched by cyclic voltammetry (CV), galvanostatic charge–discharge and electrochemical impedance spectroscopy (EIS). The results reveal that the Ni-foam@GNS@MnO 2 electrode exhibits a high specific capacitance of 462 F g −1 at 0.5 A g −1 and excellent capacitance retention of 93.1% after 5000 cycles at 10 A g −1 . Furthermore, the Ni-foam@GNS@MnO 2 electrode delivers a high energy density of 26.1 Wh kg −1 even at a high power density of 3981 W kg −1 . These results demonstrate that the Ni-foam@GNS@MnO 2 composite offers great promise in large-scale energy storage device applications.

Fully metallic nickel nanowire arrays (NWAs) electrode is prepared by electrodepositing nickel within the pores and over-plating on the surface of polycarbonate template (PCT) with subsequent dissolution of the template in dichloromethane. The as-prepared electrode is characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM) and transmission electron microscopy (TEM). Urea electro-oxidation reaction in KOH solution on the nickel NWAs electrode is investigated by cyclic voltammetry (CV), chronoamperometry (CA) and electrochemical impedance spectroscopy (EIS) tests. The results show that the nickel NWAs electrode achieves an onset oxidation potential of 0.25 V (vs. Ag/AgCl) and a peak current density of 160 mA cm −2 in 5 mol L −1 KOH and 0.33 mol L −1 urea accompanied with considerable stability.

A novel multi-walled carbon nanotubes (MWNTs)-Plastic (MP) substrate was first fabricated by adhering MWNTs on a piece of obsoleted plastic bag, and Co nano-thorns were subsequently prepared by a simple electrodeposition method on the MP surface. The morphology and phase structure of the as-prepared Co@MWNTs-Plastic (CMP) catalytic electrode are characterized by scanning electron microscopy, transmission electron microscopy and X-ray diffractometer. The catalytic activity of the CMP electrode for NaBH 4 electrooxidation is investigated by means of cyclic voltammetry and chronoamperometry. The employing of waste plastic bags reduces white pollution and the MP substrate exhibits superior stability in alkaline solution. The 3D CMP catalytic electrode owns a high electrochemical activity for NaBH 4 oxidation. Moreover, we discussed the possible mechanisms of NaBH 4 electrooxidation on the CMP.

Direct carbon fuel cells are promising power sources with their performance significantly depending on the electrooxidation activity of carbon fuel. The impurities in the carbon fuel may affect the anode reactions. Sulfur and some of its inorganic compounds (CaSO4, K2SO3, K2S, FeS2) were added in molten carbonate and their effect on graphite electrooxidation was investigated. Cyclic voltammograms of gold electrode with addition of these sulfur compounds showed CaSO4 was stable and other compounds were electrochemically oxidized to high valence state sulfur compounds at operating voltage range. Linear sweep voltammetry of graphite with addition of sulfur compounds exhibited enhanced current density compared to pure graphite electrooxidation. Chronoamperometry was carried out to examine steady-state test of graphite electrooxidation in presence of sulfur compounds and the results indicated the enhanced current densities were caused by improved Boudouard reaction for CaSO4 and sulfur electrooxidation for other compounds, respectively. These inorganic sulfur compounds had no impact on electrooxidation process of graphite.

The Mongol–Okhotsk belt and adjacent areas are key areas to study the relationship between the Okhotsk and Paleo-Pacific tectonic regimes and their superposition on the older Paleo-Asian regimes during late Mesozoic times. This paper summarizes the spatial–temporal evolution of Late Mesozoic (Jurassic–Cretaceous) granitoids and related intrusions in these areas, and interprets the magmatic evolution in terms of a transition from contractional crustal thickening to extensional thinning. According to 407 published zircon ages, these granitoids were mainly emplaced during the intervals 200–180 Ma, 180–165 Ma, 165–145 Ma, 145–135 Ma and 135–100 Ma. Jurassic granitoids (200–145 Ma) predominately occur in the Baikal–NE Mongolia (BNEM) and Great Xing’an Range. Early Cretaceous (145–100 Ma) granitoids are mainly occur in the Great Xing’an Range, and display a southward-younging migration. Significantly, Early Cretaceous granitoids also extend into the Trans-Baikal area across the Mongol–Okhotsk suture, far away from the Paleo-Pacific plate margin (in NE China); thus they were more plausibly related to post-orogenic collapse of the Mongol–Okhotsk orogen. From the Late Jurassic to Early Cretaceous, the granitoids evolved compositionally from calc-alkaline and high-K calc-alkaline, I-type, with some adakite-like features, to high-K calc-alkaline and shoshonitic, highly fractionated I-, transitional I-A or, A-type, characterized by a significant decrease in their Sr/Y ratios. This evolution coincided with a tectonic transition from contractional crustal thickening to extensional thinning. Combined with regional geology, we speculate that the Jurassic granitoids were likely derived from melting of the deep-seated, thickened lower continental crustal (LCC) sources, whereas the Cretaceous granitoids produced through crustal melting from an extensional thinning setting. Our results provide a case study demonstrating that the petrogenesis of granitic magmatism was closely associated with crustal tectonics. Early Jurassic granitoids along the Okhotsk belt formed in a subduction/collision setting related to closure of the Mongol–Okhotsk Ocean, whereas Late Jurassic granitoids in the Great Xing’an Range and in the northern North China Craton may have formed in a syn- or post-collisional setting superposed by far-field affects of subduction of the Paleo-Pacific plate. Early Cretaceous granitoids in these areas formed in response to post-orogenic extensional collapse of the Mongol–Okhotsk belt, coupled with back-arc extension related to Paleo-Pacific plate subduction.

In this report, graphene nanosheets (GNS)/nickel sulfide (NiS) based material for high-performance supercapacitor is prepared by “dip and dry” and electrodeposition methods. Commercial flexible make-up cottons (MCs) are chose as skeletons to construct homogeneous three-dimensional (3D) interconnected graphene-wrapped macro-networks, which can support structures for high loading of active electrode materials and facilitate the access of electrolytes to active electrode materials. The hybrid GNS/NiS based MCs (denoted as MCs@GNS@NiS) electrode yields relatively high specific capacitance of 775 F g−1 at a charge/discharge specific current of 0.5 A g−1 and good capacitance retention of 88.1% after 1000 cycles at 2 A g−1. Furthermore, the MCs@GNS@NiS electrode delivers a high energy density of 11.2 Wh kg−1 at even a high power density of 1008 W kg−1. Therefore, such low-cost and high-performance energy MCs based on GNS/NiS hierarchical nanostructures offer great promise in large-scale energy storage device applications.

A piece of flexible and conductive A4 paper is prepared by coating a layer of graphite with a normal 8B pencil. Then, Co nano-plates and Pd are assembled by a simple electrodeposition and chemical-reduction methods on the surface of the electrified paper, respectively. The as-prepared paper substrate/graphite-Co film-Pd (PG-CoPd) electrode is characterized by scanning electron microscopy equipped with energy dispersive X-ray spectrometer, transmission electron microscope and X-ray diffractometer. The catalytic activity of the PG-CoPd electrode for H 2 O 2 electroreduction is investigated by means of cyclic voltammetry and chronoamperometry. The preparation process of the PG-CoPd electrode does not use any binder and it exhibits a three dimensional (3D) nano structure, high stability and good electric conductivity. The mass of the Pd in PG-CoPd is about 0.0535 mg cm −2 and the reduction current density reaches to −4.30 A cm −2 mg −1 in 1 mol dm −3 NaOH and 1.4 mol dm −3 H 2 O 2 at −0.5 V, which is higher than our previous reports of Au/Pd modified Co electrode.

A novel Pd/polyaniline/CFC electrode is prepared by electroless deposition of palladium (Pd) onto three-dimensional polyaniline networks. The polyaniline matrix on the carbon fiber cloth (CFC) in the reduction state is electro-synthesized by cyclic voltammetry and has a lower vertex potential of −0.4 V vs. Ag/AgCl. The particle size of the Pd coated on the polyaniline chains is gradiently distributed. The as-prepared Pd/polyaniline/CFC electrode is characterized using scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FITR) and X-ray diffraction (XRD). The hydrogen peroxide (H2O2) electro-reduction reaction in H2SO4 solutions on the Pd/polyaniline/CFC electrode is investigated using cyclic voltammetry (CV), linear sweep voltammetry (LSV), chronoamperometry (CA) and electrochemical impedance spectroscopy (EIS). The results reveal that the electrode exhibited high catalytic activity and excellent stability in the strong oxidizing solution of H2O2 and H2SO4. Polyaniline itself shows electro-catalytic activity towards H2O2 to some extent involving the chemical–electrochemical (C–E) coupling mechanism.

In this work, RGO is decorated on MnO2 nanoflakes, which are electrochemically deposited on preformed C/TiO2 shell/core nanowire arrays to form a RGO/MnO2/C/TiO2 shell/core array electrode. Their structure and surface morphology are studied using X-ray diffraction analysis, X-ray photoelectron spectroscopy, Fourier transform infrared spectroscopy, Raman microscopy, scanning electron microscopy and transmission electron microscopy. The results suggest that a RGO layer was coated on the MnO2 nanoflakes, and the MnO2 nanoflakes have a well-distributed coverage on the surface of the C/TiO2 shell/core nanowire arrays. The RGO/MnO2/C/TiO2 shell/core arrays are evaluated as a supercapacitor electrode material, which exhibits a high specific capacitance of 822.3 F g−1 at a charge/discharge current density of 1 A g−1 and 87.4% specific capacitance retention after 5000 cycles. The superior pseudo-capacitive properties may be due to the unique shell/core structure and the decoration of RGO. The RGO decorated on MnO2 can provide partial double-layer capacitance; on the other hand, the RGO can improve the electrical conductivity of the electrode and alleviate the volume change of MnO2 during charge/discharge processes given its mechanical flexibility. Our results show that the RGO/MnO2/C/TiO2 electrode can be regarded as advantageous for electrochemical energy applications.

Nanowire-like Cu(OH)2 arrays, microflower-like CuO standing on Cu(OH)2 nanowires and hierarchical CuO microflowers are directly synthesized via a simple and cost-effective liquid–solid reaction. The specific capacitance of Cu(OH)2, CuO/Cu(OH)2 and CuO are 511.5, 78.44 and 30.36 F g−1, respectively, at a current density of 5 mA cm−2. Therefore, the Cu(OH)2/Cu-foil electrode displays the best supercapacitive performance. The capacitance retention reaches up to 83% after 5000 charge/discharge cycles with the columbic efficiency of ∼98%. More importantly, the nanowire Cu(OH)2 transformed into stable nanosheet CuO after about 600 constant current charge–discharge cycles. Additionally, we fabricate an asymmetric supercapacitor with nanowire Cu(OH)2/Cu-foil as a positive electrode, activated carbon (AC) as a negative electrode and 6 mol dm−3 KOH as electrolyte, which exhibits an energy density of 18.3 W h kg−1 at a power density of 326 W kg−1.

In this article, direct growth of Co3O4 with different morphologies on nickel foam is successfully achieved via a simple hydrothermal method by changing the volume ratio between ethanol and water. The morphology and structure of the as-prepared samples are examined by scanning electron microscopy, transmission electron microscopy, X-ray diffraction and Fourier transform infrared spectroscopy. The electrochemical performance of the Co3O4 electrodes is investigated as pseudocapacitor material by cyclic voltammetry and galvanostatic charge/discharge test in 3 mol L−1 KOH solution. Results show that the solvent composition plays an important role not only in the morphology but also in the capacitance. Co3O4 with a honeycomb structure obtained from the volume ratio of C2H5OH/H2O = 1 exhibits the highest capacitive performance, 2509.4 F g−1 at 1 A g−1 and 1754 F g−1 at 10 A g−1, which is much larger than that prepared in the pure water and pure ethanol solvent. The electrode also has a satisfactory cycling performance with capacity retention of 74% after 1000 cycles at 10 A g−1. The enhanced electrochemical performance is ascribed to the honeycomb nanostructure allowing facile electrolyte flow which speeds up electrochemical reaction kinetics. These findings may open up the opportunity for optimizing the hydrothermal synthesis conditions to control the morphology and performance of the products.

A high-performance capacitor battery AC/λ-MnO2 based on Na-ion insertion-deinsertion into λ-MnO2 in 1 mol dm−3 Na2SO4 solution is successfully demonstrated. A simple acid leaching technique is used to produce λ-MnO2 by treating LiMn2O4 with H2SO4. X-ray power diffraction and inductively coupled plasma analysis provide supporting evidences for the extraction of Li+ from the LiMn2O4, and the particle morphology of λ-MnO2 is studied by scanning and transmission electron microscopy. A high specific capacity of 390.7 mAh g−1 is obtained for the λ-MnO2 electrode at a current density of 13.6 mA g−1 with a nearly 100% efficiency. The capacitor battery AC/λ-MnO2 can operate at a cell voltage as high as 2.2 V, and it exhibits a specific energy of 19.7 Wh Kg−1 at a high power density of 3500 W Kg−1 and a high energy density of 71.7 Wh Kg−1 at a low power density of 403 W Kg−1. It has potentials to be used as an energy storage device for the integration of solar and wind power into the electrical power grid.

Cobalt and manganese oxides ((Co, Mn) 3 O 4 ) nanowires freely standing on nickel foam are prepared by a simple template-free growth process and heat treatment. The results show that the (Co, Mn) 3 O 4 composite forms a uniform film and densely covers the nickel foam substrate. The film is composed of nanowires with a diameter up to around 30–40 nm. The electrochemical capacitance behavior of the self-supported binderless nanowires electrode is investigated by cyclic voltammetry, galvanostatic charge/discharge test and electrochemical impedance spectroscopy. The (Co, Mn) 3 O 4 /Ni-foam electrode exhibits a high specific capacitance of 611 F g −1 at a charge/discharge current density of 2.38 A g −1 in 6.0 mol dm −3 KOH electrolyte. Furthermore, the (Co, Mn) 3 O 4 /Ni-foam electrode delivers a high energy density 13.6 Wh kg −1 , and even a high power density of 5.68 kW kg −1 . More importantly, the specific capacitance retention is 95% after 2000 charge/discharge cycles at 2.38 A g −1 and with columbic efficiency higher than 98%. This work suggests that the as-prepared (Co, Mn) 3 O 4 /Ni-foam electrode has potential application in electrochemical capacitors.

Three-dimensional (3D) multilayer porous MnO2/reduced graphene oxide composites are coated on a nickel foam substrate (denoted as MnO2/R-GO@Ni-foam) by a facile and scalable spray method following by low temperature annealing. The composite electrodes are characterized using X-ray diffraction, scanning electron microscopy, transmission electron microscopy and Fourier transform infrared spectroscopy. The content of MnO2 in the MnO2/R-GO@Ni-foam composites is determined by thermal gravimetric analysis. The supercapacitive performance of the composite electroides is investigated by cyclic voltammetry, galvanostatic charge–discharge and electrochemical impedance spectroscopy. The results show that the MnO2/R-GO@Ni-foam composite displays a high specific capacitance of 267 F g−1 at 0.25 A g−1 and excellent capacitance retention of 89.5% after 1000 cycles. This study provides a facile way for the preparation of composite electrodes for high-performance supercapacitor.

Three-dimensional (3D) lamination-like transition metal oxide Na 2/3 Ni 1/3 Mn 2/3 O 2 , assembled with two-dimensional (2D) ultrathin nanosheets, is successfully synthesized using a combined co-precipitation and thermal treatment method. The material was investigated, for the first time, as the positive electrode material of an aqueous Na-ion capacitor battery. The structure and morphology of the as-prepared material are systematically characterized by X-ray diffraction, scanning electron microscopy, energy-dispersive X-ray spectrometry and X-ray photoelectron spectroscopy. Its performance for Na-ion intercalation/deintercalation in a 1 mol L −1 Na 2 SO 4 aquesous electrolyte is evaluated by cyclic voltammetry, galvanostatic cycling test and electrochemical impedance spectroscopy. The Na 2/3 Ni 1/3 Mn 2/3 O 2 electrode is charged between -0.8∼1.0 V ( vs. SCE) with no water decomposed. The reversible capacity of the electrode reached 157 mAh g −1 at 0.05 C and retained to be 84 mAh g −1 and 51 mAh g −1 at 0.20 C and 0.50 C, respectively. After 80 cycles at 0.20 C, the specific capacity of Na 2/3 Ni 1/3 Mn 2/3 O 2 remains to be 42 mAh g −1 . The wide charge/discharge potential range and the high capacity reveal that the 3D lamination-like P2-Na 2/3 Ni 1/3 Mn 2/3 O 2 assembled with 2D ultrathin nanosheets can be a promising cathode material for low-cost aqueous Na-ion capacitor battery.

N-Myc downstream-regulated gene 2 (NDRG2) has recently revealed as a candidate tumor suppressor gene. To inhibit tumor growth and decrease morbidity of esophageal cancer (EC), this study aims to test the hypothesis that the upregulation of NDRG2 may suppress proliferation, invasion, migration and epithelial-mesenchymal transition (EMT) of EC cells by regulating the AKT/XIAP signaling pathway. Immunohistochemistry was conducted for the identification of NDRG2, protein kinase B (p-AKT), X-linked inhibitor of apoptosis protein (XIAP) in EC tissues. To identify the regulatory mechanism of NDRG2 on the AKT/XIAP signaling pathway and EMT in EC, over-expressed lentiviral vector and shRNA were applied for up-regulating and interfering NDRG2 expression, and a series of determinations on the biological behavior of EC cells were performed to validate this regulation action. The results of immunohistochemistry showed NDRG2 was lowly expressed in EC tissues while p-AKT and XIAP are highly expressed. Over-expression of NDRG2 suppresses the proteins related to AKT/XIAP signaling pathway and EMT. Besides, a series of determinations shows the proliferation, migration and invasion of TE-13 cells were suppressed by over-expressed NDRG2, while the cell cycle progression was blocked and cell apoptosis was promoted. And in vivo experiment also demonstrated NDRG2 could inhibit tumor growth. Our findings demonstrate over-expression of NDRG2 works as tumor suppressive role in EC through its effects on inhibition of cell migration, invasion, and EMT by inhibiting the AKT/XIAP signaling pathway.

The angiopoietin 1 (Ang1)/angiopoietin receptor (Tie2) signaling pathway may have a notable role in the pathogenesis of inflammatory diseases. The abnormal expression of angiopoietin 1 and Tie2 has also been reported in various malignant tumors, including papillary thyroid carcinoma (PTC). However, the role and mechanism of the Ang1/Tie2 pathway in the progression of PTC remains unclear. Therefore, the aims of the present study were to clarify this. Significantly high expression levels of Ang1 and Tie2 were observed in PTC tissues and cell lines. Furthermore, MTT and wound-healing assays revealed that the Ang1-mediated stimulation of human PTC cells resulted in increased proliferation and migration. Conversely, the downregulation of Tie2 levels using short hairpin RNA targeted at Tie2 abrogated the Ang1-mediated effect on cell proliferation and migration. In studying the expression of phosphoinositide-3 kinase (PI3K)/RAC serine/threonine-protein kinase (Akt) pathway, the upregulation of Ang1/Tie2 was found to be associated with the activation of the PI3K/Akt pathway in PTC. In conclusion, the data from the present study indicated that the Ang1/Tie2 induces PTC oncogenesis via the PI3K/Akt pathway, providing novel insights into human PTC therapy.

Mathematical teaching goal is the intended learning outcome and standard in mathematical teaching and learning. It can be represented as the concrete description of students’ learning results and behaviors, or an explanation of students’ growth in knowledge and skills and other aspects at the end of teaching activities. During the thirty odd years, China’s mathematical teaching goal has experienced a process of constant exploration and development, with a shift of focus from the evaluation of students’ grasp of fundamental knowledge and skills, to the evaluation of the process of students’ experience in mathematical activities and their solving of mathematical problems and their development mathematical literacy. The present teaching goal system can be seen as a three-dimensional one, which consists three aspects: knowledge and skill, process and method, emotions, attitudes and value.Under the new round of curriculum reform, the mathematical textbook editor and writer, academic experts, in-service teachers should work together in the designing, phrasing and final completing. The methodology for the design of mathematical teaching goal is an important technical problem, for which ABCD method and the method of combining internal and external are prominent. As for the realization of mathematical teaching goal, it shows both features of predetermination and estimated deviation.

Concrete is easily to crack due to its low tensile strength. Once harmful substances ingress through cracks, the service life of concrete will be endangered. The self-healing agent with a high healing efficiency and multiple autonomous is prepared based on pyrogallol and polyethylenimine. This self-healing agent is in liquid state, when the solution is exposed to air, there will be a film formed at the liquid/air interface. This film exhibited well regenerative properties which can be used to seal the cracks of concrete to reduce the risk of ingress of aggressive substances. In this paper, the ratio of the two components of the self-healing agent was investigated to achieve an optimization of strength and generation rate of this film. Then cement mortar specimens of Ф100×50 mm are immersed in the self-healing agent under a vacuum environment to let the pores fill with self-healing agent. Thereafter, the discs are subjected to gas permeability test to exam the effects of self-healing agent on the permeability of cement mortar before and after compressive loadings. Results showed that this material can effectively reduce the gas permeability coefficient of cement mortar with micro cracks. Scanning electron microscopy (SEM) results also confirmed the crack barrier effect of this self-healing agent. Through several loading cycles, this self-healing agent also retained a certain self-healing effect in cement matrix, indicating that this self-healing agent appears to be a promising approach to increase concrete durability.

Porous FeVO

Pd-Au/TiC electrodes with various three-dimensional structures are obtained by the pulsed potential electro-deposition in PdCl 2 /HAuCl 4 electrolytes. The morphologies of Pd-Au/TiC composite catalysts are significantly dependent on the component of deposited solutions. The surface appearance of Pd-Au catalysts changes from rime-shaped structure, to feather-like construction, then to pineapple root-like structure and finally to flower-like configuration with the increase of PdCl 2 content in electrolytes. These particular three-dimensional structures may be very suitable for H 2 O 2 electro-reduction, which assures a high utilization of Pd-Au catalysts and provides a large specific surface area. The electro-catalytic activities of H 2 O 2 reduction on the Pd-Au/TiC electrodes improve as increasing the Pd content in Pd-Au alloy catalysts. The pineapple root-like Pd 5 Au 1 /TiC electrode reveals remarkably excellent electrochemical property and desirable stability for catalyzing H 2 O 2 reduction in acid media. The direct peroxide-peroxide fuel cells with a 10 cm 3 min −1 flow rate display the open circuit voltage (OCV) of 0.85 V and the peak power density of 56.5 mW cm −2 at 155 mA cm −2 with desirable cell stability, which is much higher than those previously reported.

A kind of CMOS bandgap reference circuit with high order temperature compensation is introduced [1]. Compared to the traditional circuit, the bandgap reference proposed here has several advantages such as better temperature stability, smaller chip area, lower power consumption, self-power-on, and so on. Our design can be used in analog-to-digital or digital-to-analog converters, where high performance bandgap reference is required.