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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]

• Global socio-hydrology is reflected by tracing virtual water use from source to sink. • An embodiment accounting model is developed by taking account of primary inputs. • Global virtual water transfer is 30% of the direct freshwater withdrawal. • Virtual water transfer in intermediate trade is 1.4 times that in final trade. • Water self-sufficiency rate by source and that by sink are devised as new indices. To reflect a key aspect of global socio-hydrology, this paper explores global virtual water use from source of exploitation to sink of final consumption via interregional trades within the world economy as reflected by world input-output database for 2014. An embodiment accounting model is developed, which takes full account of virtual water feedbacks related to primary inputs. Global total trade volume of virtual water is estimated to be in magnitude around 30% of the global direct freshwater withdrawal. Moreover, it is revealed that global virtual water transfer in intermediate trade is in magnitude around 1.4 times that in final trade. In intermediate trade of virtual water, China, Japan and the United Kingdom turn out to be the three leading net importers, while India, Russia and the United States are revealed as the leading net exporters. In final trade of virtual water, the United States, Japan and Russia are the major net importers, in contrast to China, India and Mexico as the leading net exporters. Trade connections and imbalances of major economies in terms of virtual water are quantified and analyzed. Two new indicators in terms of water self-sufficiency rate by source and that by sink are devised. It is found that around 40% of the use of China's freshwater withdrawal finally sinks into foreign economies while only 20% of China's virtual water use originates from other regions. With regard to Germany, Canada and France, they behave like active pumps driving vast virtual water inflows and outflows, demonstrating their high involvement in the global supply chain in terms of virtual water. With the increasingly frequent virtual water transfer within the world economy, nations and regions ought to assess their behaviors in intermediate and final trades of virtual water for sustainable use of freshwater resources. [ABSTRACT FROM AUTHOR]

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]

A crucial aspect of the energy and water nexus is reflected with the revelation of the surprisingly high amount of industrial water use induced by plant infrastructure of a pilot solar power generation system in China, by means of a concrete hybrid of process analysis and Input-Output analysis. With an inclusive collection of all the input items as products of the economy, this scoping distinguishes from existing accountings that either overlook the construction stage or simply cover the plant infrastructure of solar power system as some primary materials. Supported by embodied water database from input-output analysis, the industrial water use induced by each input item is fully addressed. The industrial water use induced by the solar power plant infrastructure is revealed to be over one order of magnitude higher than that in previous scoping: this magnitude approximately doubles the life cycle industrial freshwater withdrawal of typical coal-fired power generation system for per unit amount of electricity generated. Under the 2020 scenario raised in the newly issued 13th Five Year Plan for Renewable Energy Development , the annual industrial water use induced by solar thermal power infrastructure in China is accordingly estimated, in magnitude up to around 30% of the total industrial freshwater use in Beijing in the year 2014, one-fourth of that in Tianjin, and one-tenth of that in Shanxi, respectively. In the long term water-saving planning, the promotion of solar power installations is afforded further consideration. [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]

Though carbon capture and storage (CCS) gains its momentum in China in context of the energy-mix that features heavy reliance on coal, it is currently obscure and full of uncertainty, of which a primary concern goes to the cost viability of CCS. However, previous technical-economic studies mainly take a static perspective to look into the cost of carbon capture systems, without fair consideration of the potential future cost slide brought by continuous expansion of CCS technologies and technical improvement. In recognition of this, a dynamic cost analysis is undertaken in our work by applying learning curve to exploring CCS prospect in China, together with a detailed review of domestic CCS progress. An oxyfuel power plant retrofitted from a typical traditional 2×600 MW power plant in China is chosen as a case study. The result suggests that the unit capital cost for the oxyfuel combustion plant will fall from 4926.30 RMB¥/kW to around 2977.02–3981.20 RMB¥/kW and the cost of electricity is supposed to drop drastically from the initial level 459.70 RMB¥/MWh to around 342.29–399.37 RMB¥/MWh when the aggregated capacity reaches 100 GW. The sharp decline forecasts that in the long term CCS technology could be a cost-effective option to be deployed together with other clean energy options. In addition, compared with IGCC and post-combustion systems with carbon capture, the oxyfuel combustion technology is illustrated quite competent in the long-term deployment. [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]

Abstract: Explosion containment vessels (ECVs) are widely used to completely contain the effects of explosions. A theoretical model for calculating the dynamic plastic responses of discrete multi-layered explosion containment vessels (DMECVs) has been established, which considered the effects of the strain-hardening and strain-rate on the material. The maximum displacement and equivalent plastic strain formulae have been derived for “moving separately” and “moving together” response modes. With the considerations of the effects of strain-hardening and strain-rate, three-dimensional finite element models have been developed in LS-DYNA to calculate the dynamic plastic responses of DMECVs under partial loadings. It shows that analytical and numerical results support each other, which indicates their validity. The two response modes of DMECV are confirmed in different material combinations, and a non-membrane response phase of the outer ribbon layers has been identified. Furthermore, the equivalent plastic strain of the outer ribbon layer does not change during the non-membrane response phase, which is an important characteristic for the dynamics of DMECVs. [Copyright &y& Elsevier]

• Global supply chain in terms of embodied carbon emissions is studied. • Intermediate trade of embodied carbon emissions is 2.3 times as much as final trade. • China's carbon trade deficit is twice the trade surplus of the United States. • Mainland China's final trade deficit is 1.2 times its intermediate trade deficit. • India's embodied carbon emissions are projected to double from 2012 to 2040. By differentiating intermediate trade from final trade, this paper combines typical statistics for the world economy in 2012 to explore the transfer of embodied carbon emissions via the global supply chain and the related trade imbalance. The emission transfer embodied in interregional trade is in magnitude around 40% of global direct carbon emissions. The global intermediate trade volume of embodied carbon emissions is estimated to be 2.3 times as much as the final trade volume. While Mainland China obtains a considerable economic trade surplus, its carbon trade deficit is about twice the carbon trade surplus of the United States. Mainland China's final trade deficit is around 1.2 times as much as its intermediate trade deficit of embodied carbon emissions. EU27, the United States, ASEAN and Japan serve as the major contributors to China's intermediate and final trade deficits. For the United States, its intermediate carbon trade surplus is almost equal to its final trade surplus. The United States gains a carbon surplus with most of its trading partners in both intermediate and final trades. A future scenario analysis in terms of carbon emission projection is conducted. While the direct and embodied carbon emissions of the United States and Japan are estimated to change slightly from 2012 to 2040, India's carbon emissions are projected to experience a twofold increase during the period. In the long term, though with ups and downs, the economic globalization will be inevitably moving forward, leading to a highly sliced-up global supply chain and increasingly delicate regional specialization as well as frequent intermediate trade between regions. It is suggested that nations and regions should follow this trend and adapt themselves to the global value chain by carefully assessing their roles in intermediate and final trades in terms of both currency and embodied carbon emissions. [ABSTRACT FROM AUTHOR]

Investigates the properties of YBa[sub 2]Cu[sub 3]O[sub 7-delta] (YBCO) thick films on flexible buffered metallic substrates. Utilization of pulsed layer deposition in depositing layer of YBCO; Correlation of the transport critical current density (J[sub c]) with the YBCO mosaic spread; Value of the J[sub c] obtained in the thick YBCO films.

Investigates the growth of Ruthenium Oxide thin films by pulsed laser deposition. Heteroepitaxial growth of RuO[sub 2] on Lanthanum compounds; Inquiry on the crystallinity of RuO[sub 2] thin films using Rutherford backscattering channeling measurements; Room temperature resistivity of RuO[sub 2] thin films.

Describes the structural and electrical properties of barium[sub 0.5]strontium[sub 0.5]titanium oxygen[sub 3] (BST) thin films with conductive strontium ruthenium oxygen[sub 3] bottom electrodes. Deposition of epitaxial BST thin films by pulsed laser deposition; Determination of dielectric constant and dielectric loss; Results of Rutherford backscattering spectrometry.

Fabricates high-temperature superconductor YBa[sub 2]Cu[sub 3]O[sub 7-delta] superconducting-normal-superconducting Josephson junctions using a pulsed laser deposition technique. Manifestation of the gradient doping; Confirmation of x-ray diffraction and Rutherford backscattering on good growth structure; Demonstration of microwave induced Shapiro steps.

Investigates the synthesis of epitaxial platinum films on (100)silicon using titanium nitride buffer layer. Application of pulsed laser deposition; Percentage of ion beam channeling; Properties of the multilayer structure.

Presents a method for making high current YBa[sub 2]Cu[sub 3]O[sub 7-delta] (YBCO) thick films on nickel substrates with an ion beam assisted deposition on yttria-stabilized zirconia buffer layers. Degree of in-plane mosaic spread of the films; Characteristics of the material; Effectiveness of the method for fabricating YBCO tapes in long lengths.

Prepares epitaxial YBa[sub 2]Cu[sub 3]O[sub 7-delta] (YBCO) thin films using pulsed laser deposition on strontium ruthenate buffer layers. Characteristic of the films; Indication for YBCO film crystallinity; Determination of the multilayer structure orientation relationship.

Investigates the electrical and structural properties of epitaxial SrRuO[sub 3] thin films. Use of pulsed laser deposition method; Orientation of the thin film to the substrate surface; Display of metallic behavior with a room temperature resistivity; Compatibility with high temperature superconductors.

Investigates the creation of 45 degree grain-boundary junctions. Types of substrates used; Application of continuous lattice match and photolithographic technique; Importance of the crystallinity of the bridge layer.

Examines the a-axis oriented YBa[sub 2]Cu[sub 3]O[sub 7-x] thin films on Si with CeO[sub 2] buffer layers. Orientation and texture of the films; Implications of absence of diffusion at the interface for CeO[sub 2]; Measurement of the resistance superconducting transition temperature.

Details the preparation of epitaxial (100)cesium dioxide (CeO[sub 2]) thin films on LaAlO[sub 3], sapphire, and yttria-stabilized zirconia using pulsed laser deposition. Cystallinity of the films; X-ray spectrum of the CeO[sub 2]; Random and channeling spectra for the film; Dynamic impedance for the thin film.

Details the pulsed laser deposition (PLD) of epitaxial yttria-stabilized zirconia (YSZ) on sapphire for YB[sub 2]Cu[sub 3]O[sub 7-delta] (YBCO) thin films. Film formation; Ion beam channeling measurements; Random and aligned spectra for a YSZ film; Epitaxial growth of YBCO/YSZ/sapphire by PLD.

The evolution of microstructure and texture of CuCrZr sheet is studied during cryogenic rolling. It indicates that the grains of CuCrZr alloy rolled both at room temperature and at cryogenic temperature are elongated along the rolling direction. After annealing, the grains become equiaxed with a little smaller of cryogenic rolling than that of room temperature rolling. On the other hand, as the rolling reduction increases, the dislocation density increases with a feature of twinning deformation during deep cold rolling, which results of the texture of CuCrZr alloy during cryogenic rolling occurred mainly with composition of Goss {011}< 100 > texture and Brass {011}< 211 > texture accompanied by a strong Taylor {44 11}< 11 11 8 >and Copper {112}< 111 >textures. Meanwhile, R {124}< 211 > and S {123}< 634 > textures also appear on the section of φ2 = 65°. With the increase of processing reduction, twinning deformation is occurred, and Goss {011}< 100 > orientation continues to flow to Brass {011}< 211 > orientation, with no change in the strength of Copper and Taylor textures. However, the strength of R {124}< 211 > and S {123}< 634 > textures gradually increase, but the increase is smaller than the main Brass {011}< 211 > orientation so that the yield strength, tensile strength and uniform elongation of CuCrZr alloy sheet prepared by cryogenic rolling are higher than those of room temperature cold rolling at the same deformation conditions. • During the cryogenic rolling of CuCrZr alloy with low deformation, the Goss and Brass textures are dominant. • With the increase of reduction, Brass orientation becomes stronger, and Goss orientation is weakened. • Strong Goss {011}<100>orientation and weak rotating cubic {001}<110> orientation are exhibit after solution treatment. • The texture types of room temperature cold rolling are roughly the same, but the extreme density is smaller. [ABSTRACT FROM AUTHOR]

The yield criterion is the basis of the material model that can describe the plastic behavior of the material under any possible stress states. The influence of diverse yield criteria on the formability prediction was explored via analyzing the hardening behavior and the forming limit of DP590 and DP780 sheets in this paper. The potential of the yield criterion to describe the hardening behavior of sheet metal was evaluated by comparing the equivalent stress-strain curves from the cruciform biaxial tensile tests with the uniaxial stress-strain curve. To characterize the hardening behaviors of dual-phase steel sheets under large strain condition, the hydraulic bulge tests were employed to obtain the equivalent stress-strain data based on different yield criteria. Accordingly, the material models including diverse yield criteria and hardening laws were used to calculate the theoretical forming limit curves (FLCs) based on the M-K model. Through comparing the predicted FLCs and the experimental ones from Nakazima tests, it was found that the theoretical FLCs based on the M-K model largely depend on the accurate yield criterion and hardening law. In addition, the numerical simulations of two stretch tests were carried out to verify the validity of the material models and the theoretical FLCs. The results indicated that the accurate yield criterion is of great significance to the description of hardening behavior and the prediction of FLCs. [ABSTRACT FROM AUTHOR]

Concerns surrounding climate change and environmental challenge make the coal utilization network essential not only for understanding the pattern of energy provision and transfer, but also for illustrating the interaction between anthropogenic activities and ecological systems at global level. This paper fills the research gap by dint of multi-regional input output model to outline coal embodied routes from natural boundaries to economic activities, and to identify the central hubs in the global coal supply chain, based on the most recent available statistics for 2011. As the economic value and environmental influences of different kinds of coals could be remarkably diverse, the separation of coal categories in systematic analysis could provide fundamental information regarding the displacement and teleconnection of coal utilization in the world. The estimation shows that in weight 64.99% of coal direct supply is ultimately embodied in international trade, indicating the crucial roles of trade interlinks in global coal utilization. Apart from this, the findings pertinent to sectoral structure, regional supply chain and per capita characteristics of coal embodied utilization, could be valuable to identify the global energy routes driven by international trade as well as to facilitate energy and environmental policy. [ABSTRACT FROM AUTHOR]

The household-scale biogas system gains its popularity in rural China, and is now playing a prominent role in relieving energy shortages and reducing environmental pollution. A comprehensive review is performed for related environmental and ecological assessment studies. For an overall assessment of the biogas system, especially for its renewability and sustainability, an updated exergy methodology in terms of cosmic exergy is introduced in this paper, and is concretely illustrated by a case study to an integrated biogas engineering in Hubei, China. Associated with the fundamental universal scale of the cosmic-solar-terrestrial ecosystem, this new approach aggregates natural resources, economic inputs and environmental contamination on a common basis. Furthermore, a series of cosmic exergy based indicators are established to quantify the renewability and sustainability of the system. The integrated biogas engineering is proved to be with remarkable positive net ecological benefits, around twice that of the corresponding conventional production system. Near half of resource inputs in the integrated biogas system are found to be renewable. The renewability and sustainability of the biogas system turn out to be respectively double and six times those of the conventional system. The findings are fully supportive for policy makers in their action towards further progress of biogas project for sustainable development. [ABSTRACT FROM AUTHOR]

Abstract: A new rolling force model was put forward for temper rolling strip mill considering the inhomogeneous stress distribution along the thickness of strip by investigating the similar case on the condition of totally elastic contact between roll and strip. The computing results from this model coincide well with experiments. [Copyright &y& Elsevier]

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]

Abstract Seawater desalination is one of the most essential strategies to solve freshwater shortage issues worldwide. Though having the possibility of providing abundant freshwater resources, desalination projects are also limited by the pressure of freshwater consumption. Based on the systems process analysis, the freshwater cost of seawater desalination is assessed with the case study of a 25,000 tons/day seawater desalination plant in Huanghua Port, Hebei Province, China. The total embodied water consumption is 9.02E+06 m3, which is estimated in magnitude as five percent of the total freshwater production in the design cycle. Among all the sub-projects, the embodied water consumption in the technology system engineering represents the largest component, accounting for 60.12% of the total. The productivity level of the project is calculated to be 19.29, which highlights the potential of the desalination project for alleviating the shortage of freshwater. It is necessary to notice that the water yield of the project is calculated to be 9.12E+06 m3, which could achieve the freshwater balance of the construction phase in the first year of operation. The comprehensive inventory and procedure of the embodied water accounting in this work are expected to provide useful references for rational allocation of water resources and optimal design for other desalination projects. Graphical abstract Image 1 The pyramid model of freshwater cost levels. Highlights • The freshwater costs of the Huanghua Seawater Desalination are 9.02E+06 m3. • The productivity of the project is 19.29 m3 net water/m3 required water. • Materials with different levels of freshwater costs are compared and assessed. • The net freshwater volume per year of the project reaches 8.70E+06 m3. • The water demands of 8 enterprises in Cangzhou are meet by the project. [ABSTRACT FROM AUTHOR]

To identify the size effects on the mechanical behavior of microparts is essential for micro-forming. Here, the size effect on the tensile properties of commercial pure titanium foils with thickness ranging from 5 µm to 200 µm has been investigated. The tensile strength, yield strength and work-hardening rate reach a minimum value at the thickness of 30 µm because the main deformation microstructures including dislocations, twins and deformation induced face-centered cubic titanium (fcc-Ti) are different in different foils. The density of deformation twins decreases as the thickness decreases. However, the density of fcc-Ti increases and reaches a maximum value at the thickness of 30 µm. The dominant deformation mechanism is dislocation slip when the thickness is below 20 µm. The yield strength decreases with the decrease in thickness because of the strengthening effect of fcc-Ti being smaller than that of twins when the thickness is above 30 µm. When the ratio of the thickness to grain size is below 5, the yield strength increases with the decrease in thickness due to the large volume fraction of oxides layer on the surface. Based on these, two kinds of constitutive equations have been well established in consideration of the grain size or the ratio of the thickness to grain size. [ABSTRACT FROM AUTHOR]

To identify the size effects on the mechanical behavior of microparts is essential for micro-forming. Here, the size effect on the tensile properties of commercial pure titanium foils with thickness ranging from 5 µm to 200 µm has been investigated. The tensile strength, yield strength and work-hardening rate reach a minimum value at the thickness of 30 µm because the main deformation microstructures including dislocations, twins and deformation induced face-centered cubic titanium (fcc-Ti) are different in different foils. The density of deformation twins decreases as the thickness decreases. However, the density of fcc-Ti increases and reaches a maximum value at the thickness of 30 µm. The dominant deformation mechanism is dislocation slip when the thickness is below 20 µm. The yield strength decreases with the decrease in thickness because of the strengthening effect of fcc-Ti being smaller than that of twins when the thickness is above 30 µm. When the ratio of the thickness to grain size is below 5, the yield strength increases with the decrease in thickness due to the large volume fraction of oxides layer on the surface. Based on these, two kinds of constitutive equations have been well established in consideration of the grain size or the ratio of the thickness to grain size. [ABSTRACT FROM AUTHOR]

The forming limit curve (FLC) provides a convenient way to forecasting the failure of metallic sheet in stamping process. In this paper, the FLC in hot stamping of the advanced high strength steels was evaluated through applying the M–K model and Hill 48 criterion with the consideration of the sheet temperature history. The temperature variation and the limit strains of the deformed sheet in the Nakazima test were both experimentally and theoretically studied. The comparison between the experimental and theoretical results in terms of temperature history and limit strain revealed that the predicted FLC, which was dissimilar to the conventional one under the isothermal condition, could well fitted the experimental data. The effect of the temperature history on sheet formability was theoretically demonstrated, the improvement of the forming limit was interpreted through comparing the limit major strains in different temperature histories and strain states. The results illustrated that the temperature history made the limit major strain in balanced biaxial strain state increasing by 12.7%. [ABSTRACT FROM AUTHOR]

In this paper, a modified ductile fracture criterion was established to predict the fracture behavior of DP590 sheet based on Lou-Huh model. Considering the change of loading path during the plastic forming process, the C-H model was introduced to interpret the whole loading history. According to C-H model, the plastic loading process is divided into three stages including homogeneous deformation, deformation localization and localized instability. In addition, the variations of stress triaxiality and Lode parameter were tracked by the corresponding stress ratios under three tensile deformation patterns including uniaxial tension, plane strain tension and equi-biaxial tension. Based on the optimization algorithm, the material constants of the original and modified Lou-Huh fracture criteria were determined and their theoretical fracture limit strains were compared with the experimental one. Furthermore, the morphology of fracture surfaces was also taken to characterize the ductile fracture behavior of DP590 sheet. Results showed that the modified Lou-Huh model is more suitable for the prediction of ductile fracture of DP590 sheet, and the growth and shear coalescence of microvoids are correlated with stress triaxiality and Lode parameter, which change with the development of plastic deformation. [ABSTRACT FROM AUTHOR]

Virtual water consumption accounting for an entire building construction engineering project including nine sub-projects is presented in this study to reveal the full picture of water consumption in building construction engineering. With the most comprehensive first-hand project data, this study is the first attempt to quantify a whole engineering project's virtual water consumption to the best of our knowledge. As numerous works have been undertaken for on-site water conservation in buildings, further efforts should be devoted to assessing water embodied in the construction process and intermediate material inputs. This research selects the construction engineering of a cluster of landmark commercial buildings in Beijing Economic-Technological Development Area as a case study and derives more than 1000 items of first-hand project data from the Bill of Quantities. Based on the standard building construction classification, the total virtual water consumption of the nine sub-projects is quantified as 1.92E+06 m 3 , almost 24 times as much as the on-site water consumption. As the dominant sub-project, Structure and outside decoration engineering contributes more than half of the total water consumption. Fully considering the direct and indirect water embodied in the construction engineering, building materials, in particular steel, cement, lime, and metal products, contribute to more than 3/4 the total water consumption. As the virtual water consumption of China's annual increased building areas reaches 1/4 the direct national water consumption, both direct and indirect water consumed in the process of building construction should gain full attention. [ABSTRACT FROM AUTHOR]

The facilitation of regional trade has boosted the fragmentation in global supply chain, integrating the production, energy and other ecological factors across the regional boundaries by virtue of vertical specialization. The consequences of this trend on urban energy consumption are firstly analyzed by constructing multiregional input–output table and decomposing the value added export in Beijing. Energy consumption per unit of GDP in Beijing is only half of that per unit of value added after adjusting the export by virtue of decomposition techniques and Beijing displays no obvious advantages in energy usage when considering the value added processes. Energy intensive parts of production are relocated outside the metropolis by the downstream and upstream participation in global areas. The results of value added export for energy consumption reveal that the vertical specialization in this metropolis slashes the amount of energy consumption in the city but raises that in the outside. The unified framework by integration of the value added export and energy consumption in this paper could be extended to other related topics. [ABSTRACT FROM AUTHOR]

Hydropower fuels the overall societal development by contributing a notable proportion to the whole global power generation. Although much attention has been paid to the development of hydropower, few of them attempted to gather global systematic data and conduct a large-scale review of scientific studies. In such situation, a bibliometric approach is employed in this study to quantitatively evaluate global scientific research on hydropower sustainable development, with a long time span ranging from 1991 to 2012. 434 publications in accordance with the search criteria from Science Citation Index Expanded (SCI-Expanded) database are analyzed statistically, and assessments on research development, current trends, and future directions are conducted in regard to eight categories. By synthetically analyzing the keywords, the dominant hotspots of hydropower sustainable research could be concluded as “Turkey”, “Eco-”, “Small hydro-”, and “Fish”. Along with a comparable number of publications to the United State, the keyword “Turkey” has exhibited a notable increase since 2000, revealing its predominance in the research on the hydropower sustainable development. Increasing attention has also been directed to the prefixes “Small hydro-” and “Eco-” in recent years. The keywords related to fish are identified from the keyword analyses as well, suggesting that the significance of fish studies has been recognized by researchers. Given the trend during the past several years, these topics are likely to become primary research focuses in the coming period. [ABSTRACT FROM AUTHOR]

• An automatic method for measuring welding quality based on deep learning is proposed. • A semantic segmentation algorithm for detecting welding defects is implemented. • The radiographic dataset for training and evaluation the algorithm is collected. • A suitable deep learning neural network architecture is selected and a corresponding optimization strategy is designed. • The robustness and versatility of the measurement method are verified. In order to remove the limitations of human interpretation, many computer-aided algorithms have been developed to automatically detect defects in radiographic images. Compared with traditional detection algorithms, deep learning algorithms have the advantages of strong generalization ability and automatic feature extraction, and have been applied in welding defect detection. However, these algorithms still need further research in the acquisition and cleaning of welding radiographic image data, the selection and optimization of deep neural networks, and the generalization and interpretation of network models. Therefore, this paper proposes an automatic welding defect detection system based on semantic segmentation method. Firstly, a dataset of radiographic images of welding defects, called RIWD, is set up, and the corresponding data preprocessing and annotation methods are designed for the training and evaluation of the algorithm. Secondly, an end-to-end FPN-ResNet-34 semantic segmentation network-based defect detection algorithm is implemented, and the network architecture is experimentally demonstrated to be suitable for defect features extraction and fusion. Thirdly, to improve the detection performance of the algorithm, an optimization strategy for the network is designed according to the data characteristics of defects, which includes data augmentation based on combined image transformations and class balancing using a hybrid loss function with dice loss and focal loss. Finally, to ensure the reliability of the algorithm, the generalization ability of the algorithm is tested using external validation, and the defect features learned by the network are visualized by post-interpretation technique. The experimental results show that our method can correctly discriminate defect types and accurately describe defect boundaries, achieving 0.90 mPA, 0.86 mR, 0.77 mF1 and 0.73 mIoU, which can be applied to automatically interpret radiographic images. [ABSTRACT FROM AUTHOR]

Abstract: Shot peening is an effective surface treatment method, which can improve the fatigue properties of metallic materials. In the present paper, the residual compressive stress field induced in TC4-DT titanium alloy under different shot peening conditions and the thermal relaxation behaviors of shot-peened TC4-DT were discussed. The shot peening can cause residual compressive stress on the material surface compared to un-peened materials. The subsurface residual stress distributions of original and shot-peened specimens were measured by an X-ray diffraction method. The residual compressive stress profiles accord with the characteristic curve of residual stress field. The maximum residual compressive stress is located at subsurface layer. Surface roughness also increases with increasing shot peening intensity. There is relaxation of residual compressive stress during temperature. Thermal relaxation behavior of residual stress was studied at 150 and 300°C with different ageing time. The residual stress relaxation is influenced by temperature and time during ageing. Thermal relaxation of residual stress is a thermal recovery process. The relaxation process of thermal residual stress is analyzed by applying the Zener–Wert–Avrami function. [Copyright &y& Elsevier]

In-depth understanding of the evolving plastic yielding behaviors and insight into their micro-scaled mechanisms are critical for fully exploiting of the formability of sheet metals, accurately forming of the needed shape and geometries, and precisely tailoring of the needed quality and property of the deformed parts. In this research, the in-plane yielding behaviors of dual-phase steel and aluminum alloy sheets were extensively investigated by biaxial tension experiments with the original and pre-strained specimens. It is found that the profile of the experimental plastic work contours changes with the increase of plastic deformation, no matter what the proportional or complex loading condition is. This indicates that the evolving yield behavior cannot be neglected. Based on the Yld2000-2d yield function, a modified yield function with introducing a variable exponent to represent the evolving yield behavior was proposed and then employed to model the evolving yielding of the given metallic sheets. To investigate the yielding micro-mechanisms, the simulated biaxial tension tests were conducted by using the established representative volume elements (RVEs) with a crystal plasticity model. The simulation results showed that the texture of the given sheet metals has a significant effect on the profile of the yield loci. Moreover, when the hard secondary phase is added into the polycrystalline aggregate, the optimum exponent of yield function for the given RVEs is increased, instead of decrease within a certain range of the plastic strain. The micro-mechanism of the evolving yielding behavior could be attributed to the 'pinning' effect of hard inclusions to the polycrystalline grains, i.e. the hardly-deformable particles strengthening the kinetic constraints to the polycrystalline matrix and further obstructing the rotation and plastic deformation of the neighboring grains. This research thus provides a comprehensive understanding of the effect of microscopic structure (crystal structure, texture and secondary hard phase) on the macroscopic plastic yielding behavior of metallic materials as well as a new high-fidelity modelling technique to describe the evolving yielding behavior phenomenologically, in such a way to support the application of FE simulation in sheet metal forming processes. Image 1 • The multiple biaxial tensile results revealed the evolving yielding behavior of the given sheet metals. • A modified yield function with a variable exponent was proposed to model the evolving yield behavior. • The evolving yield behaviors were found to be caused by polycrystal grain rotation. • Hard phase affects the evolving yielding behavior by obstructing the rotation of adjacent grains. • The modified yield function with a variable exponent enhances the accuracy in FE simulation. [ABSTRACT FROM AUTHOR]

Investigates ab-plane anisotropy of the critical currents in twinned YBa[sub 2]Cu[sub 3]O[sub 7-delta] superconductor films. Deposition of films on crystalline yttria-stabilized zirconia (YSZ); Effect of the alignment of the twin boundary mosaic diagonal; Nucleation of the YSZ buffer layer in large grains.

Investigates the pulsed laser deposition of thick YBa[sub 2]Cu[sub 3]O[sub 7-delta] films. Determination of the critical densities of the thinnest films; Effect of increasing the film thickness; Orientation and texture of the film.

Characterizes the formation of epitaxial metallic lanthanum nickel trioxide (LNO) thin films using pulsed laser deposition. Crystallinity of LNO films; Resistivity of LNO films to electricity; Diffusion of nickel ion from the LNO film into yttrium barium copper oxide films.

Examines the growth of (110)-oriented cerium dioxide (CeO[sub 2] layers on (100) silicon substrates. Importance of the electron-beam evaporation in CeO[sub 2] growth; Characteristics of CeO[sub 2] epitaxial layers; Interface between the amorphous layer and the silicon substrate.

Measures the residual loss in epitaxial YBa[sub 2]Cu[sub 3]O[sub 7] thin films from microwave to submillimeter wave frequencies. Use of weakly coupled superconducting grain model and a homogeneous two-fluid model.

Demonstrates that uniform, two-sided 90 K coatings can be deposited on five-centimeter-diameter substrates by pulsed laser deposition. Efficacy in producing superconducting films on both sides of substrate wafers; Values of the obtained thickness and stoichiometric variations.

Prepares single-crystalline epitaxial YBa[sub 2]Cu[sub 3]O[sub 7-x] thin films by a plasma-enhanced metalorganic chemical vapor deposition (MOCVD). Formation of the films on lanthanum aluminum oxide substrates; Degree of epitaxial crystallinity of the films; Applications of MOCVD.

Investigates the influence of processing parameters on the quality of YBa[sub 2]Cu[sub 3]O[sub 7-x] thin films produced by pulsed laser deposition. Evolution of microscopic columnar structures; Decrease in deposition rate; Alignment of columnar structures.