LOCAL CHEMISTRY AND THE COHESIVE STRENGTH OF GRAIN BOUNDARIES IN Ni_3Al

Local chemistry plays an important role in determining the cohesive strength of grain boundaries in Ni3Al. Doping with B increases the room temperature ductility and changes the fracture mode from intergranular to transgranular, while doping with Zr increases the ductility but leaves the fracture mode predominantly intergranular.Electron Energy Loss Spectroscopy (EELS) and Energy Dispersive X-ray Spectroscopy (EDS) were used to probe the changes in local bonding (and hence the cohesive strength) produced by changes in local chemistry at large angle boundaries in Ni3Al.In addition , small angle tilt boundaries were studied to correlate structure with Nienrichment at the interface. B segregation to Ni-rich grain boundaries was shown to make the bonding similar to that of the bulk, thereby increasing their fracture resistance. Ni-enrichment does not occur in the presence of Zr segregation to grain boundaries. Ni-enrichment to antiphase boundaries (APB) in small angle tilt boundaries lowers the APB energy by reducing the number of high energy Al-Al interactions across the interface. Ni-enrichment to large angle boundaries is expected to produce a similar effect on energy.

LOCALIZED STUDIES ON ELECTRONIC STRUCTURE AND CHEMICAL BOND FOR [NCCuS_2MoS_2]^(2-) CLUSTER

The canonical and locatized molecutar orbiters of [NCCuS_2NoS_2]^(2-) cluster were calculated by means of CNDO quantum chemistry method. Then the energy and properties of corresponding chemicat bonds were discussed, especially, Cu-Sb-No three center conjugated π bonds and No-St-No conjugated π bonds were accounted for.

Charge state modulation on boron site by carbon and nitrogen localized bonding microenvironment for two-electron electrocatalytic H_(2)O_(2)production

Design of electrochemical active boron(B)site at solid materials to understand the relationships between the localized structure,charge state at the B site and electrocatalytic activity plays a crucial role in boosting the green electrochemical synthesis of hydrogen peroxide(H_(2)O_(2))via two-electron oxygen reduction(2eORR)pathway.Herein,we demonstrate a carbon(C)and nitrogen(N)localized bonding microenvironment to modulate the charge state of B site at the boron-carbon nitride solid(BCNs)to realize the efficient selective electrocatalytic H_(2)O_(2)production.The localized chemical structure of N-B-N,N-B-C and C-B-C bonds at B site can be regulated through solid-state reaction between boron nitride(BN)and porous carbon(C)at variable temperatures.The optimized BCN-1100 achieves an outstanding H_(2)O_(2)selectivity of 89%and electron transfer number of 2.2(at 0.55 V vs.RHE),with the production of 10.55mmol/L during 2.5 h and the catalytic stability duration for 15000 cycles.Further first-principles calculations identified the dependency of localized bonding microenvironment on the OOH~*adsorption energies and relevant charge states at the boron site.The localized structure of B site with BNC_(2)-Gr configuration is predicted to be the highest 2eORR activity.

Analysis of the Pull Effect of Local Government Special-Purpose Bond Investment on Economic Growth Under the Input-Output Framework

In this paper,we discuss the development process of local government special bonds,and the role channels of local government special debt investment in driving China’s economic growth.Based on the specific decomposition of Xinjiang local government special bond investment,this paper uses the non-competitive input-output model for the first time to analyze the net pulling effect of Xinjiang local government special bond investment on Xinjiang’s GDP and employment in 2020.Two measure calibers are set in this paper based on whether the financing costs are considered or not;in addition,we set up four scenarios based on two conditions:Whether to consider retained fun and whether to consider using special-purpose bond investment to leverage social capital.The results show that:1)when financing costs are not considered,the RMB77.4 billion local government special-purpose bonds can push the GDP of Xinjiang to grow by RMB42.27 billion,RMB35.12 billion,RMB77.548billion and RMB69.34 billion respectively under the four scenarios;2)when financing costs are not considered,the number of jobs driven by the RMB77.4 billion local government special-purpose bonds was respectively 372,300,324,500,718,500 and 601,300 in the four scenarios;3)when financing costs are considered,the RMB77.4 billion local government special-purpose bonds can push the GDP of Xinjiang to grow by RMB71.876 billion and RMB64.268 billion under scenario 3)and scenario 4).

Why Local Bonds Failed to Sell

The Central Government is allowing all provincial governments to issue local bonds to help finance the construction of public welfare facilities. But so far investors haven’t shown much interest in the bonds-the first of their kind to be issued in China. Ni Xiaolin, a senior commentator at Xinhua News Agency, discusses why in the following article she wrote for Beijing Review.