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In this work, the degradation of mechanical properties of galvanized steel under wind and sand erosion environment was studied. The law of weight loss of galvanized steel in corrosive environment was studied by accelerated corrosion experiment. The micro‐morphology and formation mechanism of corrosion products were investigated in detail by scanning electron microscopy and x‐ray diffraction, respectively. In addition, the mechanical properties of galvanized steel such as elastic modulus, yield strength, ultimate strength and elongation were investigated in detail. The results show that the weight loss rate of the zinc layer on the surface of galvanized steel follows an exponential function. Without the protection of the zinc layer, the mechanical properties of the steel will decrease quickly. Therefore, a zinc layer on the steel is necessary. Besides, it is necessary to strengthen the hot‐dip galvanizing treatment on galvanized steel. This work provides a valuable reference for the corrosion behavior and protection measures of galvanized steel in the wind and sand environment. [ABSTRACT FROM AUTHOR]

A ramp edge-geometry superconductor-normal-superconductor configuration was used to develop high-temperature superconducting Josephson junctions and direct current superconducting quantum interference devices. The electrodes used was Ag-doped YBa2Cu3O7-x and the barrier employed was PrBa2Cu3O7-x. The devices exhibited a voltage modulation of 37 micro V and a magnetic field noise of -2 pTHz(super 1/2) at 1 kHz.

The structural and electric properties of high temperature superconducting YBCO SNS Josephson junctions fabricated via unique normal-metal layer construction are investigated using current-voltage measurements, x-ray diffraction analysis and Rutherford backscattering spectrometry. Results show that the junctions have an N layer which consists of a gradient Pr:YBCO multilayer configuration. They also show excellent electrical properties above liquid nitrogen temperature.

The optimal conditions for off-axis magnetron sputtering of multilayered YBa2Cu3O(7-x) (YBCO) films on magnesium oxide substrates were investigated with the further aim of developing superconducting-normal-superconducting junctions. Among the deposition parameters evaluated were film nucleation temperature, substrate-target relationship and oxygen annealing period. Consequently, it was shown that a lower nucleation temperature enhances the crystallinity and in-plane orientation of the YBCO films.

The pulsed laser deposition of YBa2Cu3O(7-delta)/BaTiO3/YBa2Cu3O(7-delta) (YBCO) multilayers on silicon substrates buffered by yttrium-stabilized zirconia layers was studied as a means of fabricating epitaxial ferroelectric capacitors. The approach, which employed YBCO layers as metallic electrodes, yielded multilayer structures with a c-axis orientation normal to the substrate.

The multiple-zone flow-through thallination process has been successfully employed to fabricate smooth Tl2Ba2CaCu2O8 and TlBa2CaCu2O7 thin films on LaAlO3 substrates. The scalable process requires the use of Ba2CaCu2O5 precursor films, thallic oxide and oxygen or argon as the carrier gas. It yields Tl2Ba2CaCu2O8 films with inductive transition temperatures of 107.6 K, critical current densities of 130 kA/cm2 at 75 K and surface resistances of 1.3 milli-ohm at 10 GHz and 80 K.

The characterization of Nd1.85Ce0.15CuO(4-y) (NCCO) thin films epitaxially grown on sapphire substrates with a yttria-stabilized zirconia buffer layer was performed. This was carried out via x-ray diffraction and transmission electron microscopy techniques as well as microwave surface resistance measurements. Based on the results, a heterostructure consisting of an yttrium-barium-copper-oxide layer, a dielectric layer of SrTiO3 and an NCCO layer was prepared.

Ion beam assisted deposition is used to create textured yttria-stabilized-zirconia buffer layers on flexible nickel substrates prior to the preparation of high current YBa2Cu3O7-gamma thick films. This approach enables the formation of c-oriented thick films with strong in-plane textures. The films produced using this method also exhibit excellent resistance to high magnetic fields at cryogenic temperatures.

Studies on the superconducting and structural properties of Nd(sub 2-x)Ce(sub x)CuO(sub 4-y) films of varying thickness grown on several substrates reveal that the differences in superconducting properties result from film strains introduced by lattice mismatch and the charge imbalance at the interface. n-type SuFET structures built on fluorite-type substrates of YSZ are better superconductors than perovskite-type substrates.

A study was conducted on the surface topography of superconducting YBCO thin films. The films were prepared by pulsed laser deposition. Critical current densities observed in the YBCO thin films were found to be larger than those existing in bulk materials. Screw dislocations were also found to be either repulsive or atractive depending on the dominant pinning mechanism and also affected current densities. Frequent oxygen defects were attributed to flux pinning.

Direct Observation of Structural Defects in Laser-Deposited Superconducting Y-Ba-Cu-O Thin Films THE MOST IMPORTANT QUESTION concerning the potential of the new high-superconducting transition temperature ([T.sub.c]) cuprate superconductors for large-scale applications [...]

Abstract Within a single integrated globalized economy featuring robust fluxes of interregional trades, the world economy is like a giant bathtub containing the world inventory of energy use. Based on different norms or ethic percepts, the energy use of the world economy is reallocated to nations and regions via global supply chain using normative accounting schemes. By combining typical statistics for world economy 2012, a new perspective is presented in this study to look into the energy use of regional economies from the side of genuine final consumers. Parallel to the final-demand-based accounting method, a total-consumption-based multi-region input-output accounting method is developed following the norm of consumption being the ultimate end and purpose of all producing activities. From a total-consumption-based perspective, the energy use of the United States economy is shown in magnitude 1.8 times that of mainland China, compared to a ratio of 88% from a territorial-based perspective. The consumer-product-related trade imbalances of major economies in terms of both currency and energy use are analyzed, with major interregional net trade flows illustrated. While the United States and mainland China are respectively revealed as the leading net exporter and net importer of currency, the energy trade deficit of the latter is in magnitude around four times the energy trade surplus of the former. The trade structures by geography and sector are respectively presented for the United States and mainland China as two distinct economies. It is found that around half of the United States' exports of energy use originate from transport and service industries, while nearly 90% of mainland China's exports of energy use come from heavy industry. The findings are supportive for nations to identify their roles in the global supply chain from the perspective of genuine final consumers and adjust the trade patterns for sustained energy use. Graphical abstract Unlabelled Image Highlights • A global energy profile is constructed from the side of genuine final consumers. • A total-consumption-based multi-region input-output accounting scheme is developed. • Energy use of the United States is 1.8 times that of mainland China. • Mainland China accounts for 40% of global total exports of energy use. • Energy trade imbalance of Mainland China is four times that for the United States. [ABSTRACT FROM AUTHOR]

Coal-based power generation accounts for over two fifths of global electricity supply and is supposed to be continuing its leading role in the coming decades. However, an integrated embodied energy accounting for typical coal-fired power system seems to be in its vacancy. To help erect a benchmark for energy analysis of electricity production, this study has for the first time established a complete inventory of energy inputs in the life cycle of a typical coal-fired power plant. Distinguished from previous works, with the support of ecological input–output database, this paper gives full consideration to the energy embodied in materials, equipment and services that have been traditionally neglected. The indirect energy cost is illustrated to be a non-negligible component, sharing around one-tenth of the total. This work could be a reference example for holistic energy evaluation of power generation systems worldwide. In current context of energy conservation and emissions abatement, it is of significant importance as the retrofitting of power generation systems may initiate large amounts of indirect energy cost. Besides, by calculating the nonrenewability indicator for the typical coal-fired power system, the energy saving potentials of several renewable alternatives are enunciated in this work. It may provide essential implications for policy makers in renewable deployment. [ABSTRACT FROM AUTHOR]

Energy-related greenhouse gas emission is emerging as a major concern to be addressed. The structure of the urban economy, as the center of energy consumption, has therefore arrested widespread attention on the globe. By employing input–output model as a dynamic approach to simulate urban metabolism processes, structure decomposition analysis is undertaken as a unified framework to clarify the underlying reasons behind increment of GHG emission in Beijing with the latest data. The eight components classified into three categories of changes, i.e., intensity structure, production linkage, and final demand are investigated from the perspectives of comparative contribution and hierarchical structure, identifying the crucial components for total changes and the characteristics within each category at the aggregated and sectoral levels. The asymmetries of contribution across the components and the essential implications for policy makers are presented. [ABSTRACT FROM AUTHOR]

Integrated biogas utilization has experienced a rapid development in recent years in rural China, for both renewable energy production and waste treatment. On the basis of a modified Ecological Footprint (EF) indicator, this paper provides a comprehensive assessment of a “pig–biogas–fish” system, a typical household integrated biogas-utilization system in southern China, by focusing on the resources consumed and produced within the system. The method of Emergy Environmental Footprint as a combination of EF and emergy accounting is introduced to quantify the sustainability of the overall biogas system and its three subsystems. Results reveal that the resource use intensity of the “pig–biogas–fish” system, defined as the ratio of footprint investment to footprint delivered, is 0.48. Compared with the conventional animal husbandry system, the “pig–biogas–fish” system proves to be of higher sustainability. And the findings have essential policy making implications supportive to a further spread of integrated biogas-utilization modes in rural areas. [ABSTRACT FROM AUTHOR]

With the expansion of urbanization in China, the integrated biogas-utilization system has gained its popularity for both renewable energy production and multi-level utilization of organic waste. To appraise the ecological performance of the integrated biogas system, systematic accounting is undertaken for an integrated “pig–biogas–fish” system in Hubei province, China. Based on Odum's concept of embodied solar energy as a unified measure for environmental resources, human labors and purchased goods, a set of emergetic indicators are employed to quantify the system sustainability. The results reveal that in a 20-year designed lifetime scenario, 94.69% of the total emergy inputs for the “pig–biogas–fish” system are attributed to purchased social resources. Three kinds of products, namely pig, biogas, fish are taken into consideration, and transformity of the “pig–biogas–fish” system is calculated as 1.26E + 05 seJ/J. Compared with the Chinese conventional agriculture system, the integrated biogas system shows a higher sustainability. Given that most biogas systems have a lifespan less than 20 years, for the “pig–biogas–fish” system, six other scenarios with different lifespans are studied to investigate the impact of the lifespan on sustainability. The findings suggest that the “pig–biogas–fish” system should be well operated for at least 8 years to prove its advantage in ecological economy over the conventional agriculture system. This has essential policy implications that local government should strengthen subsequent management on biogas production to extend the practical service life of the biogas system. [ABSTRACT FROM AUTHOR]

A multi-beam cylindrical lens antenna operating at mm-wave frequencies has been designed using dielectric-filled parallel plate techniques. The system is composed of a homogeneous cylindrical lens and an arc feed array of planar linearly tapered slot antenna (LTSA). The cylindrical lens is made out of Rexolite (∊T=2.54) and sandwiched between two parallel plates. The LTSA feed array is placed between the parallel plates at the periph-ery of the cylindrical lens to launch multiple beams. A ray-tracing method and CST-MWS are used to analyze and design this cylindrical lens antenna at 30 GHz. Measured results of a fabricated cylindrical lens, with a diameter of 100 mm, show good agreement with simu-lations. The measured 3-dB E- and H-plane beamwidths are 6.0° and 52°, respectively, and the sidelobe level in the E-plane is --14.7 dB. An impedance bandwidth of 16.7% is achieved over which the measured aperture efficiencies are better than 61.5%. The mea-sured £-plane patterns of a 25-beam array with a crossover of --3 dB and a scan angle of 150° are also demonstrated, which provide a wide scan angle at mm-wave band. [ABSTRACT FROM AUTHOR]

High-temperature superconducting Josephson junctions and dc SQUIDs were fabricated using a ramp edge-geometry SNS configuration. Ag-doped YBa/sub 2/Cu/sub 3/O/sub 7-x/ was used as electrodes and PrBa/sub 2/Cu/sub 3/O/sub 7-x/ as barrier. The I/sub c/R/sub n/ value of the junctions was in excess of 120 /spl mu/V at 75 K. The dc SQUIDs showed a flux modulation depth, /spl part/V//spl part//spl Phi/, over 150 /spl mu/V//spl Phi/, at 75 K. The flux noise of the devices, measured with dc bias currents operated at 75 K, showed a 1/f dependence at low frequency having values below 100 /spl mu//spl Phi//sub 0/Hz/sup - 1/2 / (the best values in the range of 30/spl sim/40 /spl mu//spl Phi//sub 0/Hz/sup - 1/2 /) at 1 Hz and less than 5 /spl mu//spl Phi//sub 0/Hz/sup - 1/2 / in the white noise region. The voltage modulation and magnetic field noise were 37 /spl mu/V and /spl sim/2 pTHz/sup - 1/2 / at 1 kHz for the directly-coupled dc SQUID magnetometers (with a pick-up loop 6 mm/spl times/ 3.5 mm) based on the ramp edge-geometry SNS configuration. [ABSTRACT FROM PUBLISHER]