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Industrial fusion of microalloying elements in steelmaking is imperative in defining and optimizing certain steel properties due to their strengthening and significant grain refinements effects at minute quantities. Copper, vanadium, and columbium are explored in this investigation to monitor their respective dissolution processes in a ladle metallurgy furnace (LMF), with concise parametric studies on effects of number of plugs and variations in argon gas flow rates for stirring. To track particle disintegration in the molten bath inside, intricate numerical processing was carried out with the use of mathematical models and to simulate the mixing process; turbulent multiphase computational fluid dynamics (CFD) models were combined with a user-defined function. The numerical findings highlight the connection between mixing time and gas blowing since the quantity of stirring plugs employed and the gas flow rates directly affect mixing effectiveness. The amount of particles to be injected and their total injection time were validated using industrial measurement; an average difference of 9.9% was achieved. In order to establish the need for an exceptionally high flow rate and inevitably reduce resource waste, extreme charging of flow rates for gas stirring were compared to lesser gas flow rates in both dual- and single-plug ladles. The results show that a single-plug ladle with a flow rate of 0.85 m3/min and a dual-plug ladle with a total flow rate of 1.13 m3/min have the same mixing time of 5.6 min, which was the shortest among all scenarios. [ABSTRACT FROM AUTHOR]

Industrial fusion of microalloying elements in steelmaking is imperative in defining and optimizing certain steel properties due to their strengthening and significant grain refinements effects at minute quantities. Copper, vanadium, and columbium are explored in this investigation to monitor their respective dissolution processes in a ladle metallurgy furnace (LMF), with concise parametric studies on effects of number of plugs and variations in argon gas flow rates for stirring. To track particle disintegration in the molten bath inside, intricate numerical processing was carried out with the use of mathematical models and to simulate the mixing process; turbulent multiphase computational fluid dynamics (CFD) models were combined with a user-defined function. The numerical findings highlight the connection between mixing time and gas blowing since the quantity of stirring plugs employed and the gas flow rates directly affect mixing effectiveness. The amount of particles to be injected and their total injection time were validated using industrial measurement; an average difference of 9.9% was achieved. In order to establish the need for an exceptionally high flow rate and inevitably reduce resource waste, extreme charging of flow rates for gas stirring were compared to lesser gas flow rates in both dual- and single-plug ladles. The results show that a single-plug ladle with a flow rate of 0.85 m3/min and a dual-plug ladle with a total flow rate of 1.13 m3/min have the same mixing time of 5.6 min, which was the shortest among all scenarios.

In this work it a strong evidence of the hydrated electrons production was shown in a film of condensed water, by directing the injection of electrons in localized and/or delocalized water electronic states using a system of high voltage made in laboratory. The results show that the water layers on the silica particles are electrically charged by injection of electrons from a metal electrode when silica is placed in high electric field. This charging process also appears to depend on the thickness of these water layers and of the spatial arrangement required by the silica surface. [ABSTRACT FROM AUTHOR]

Demonstrates the occurrence of continuous injection processes. Charge injection data on epoxy resin samples; Calculation of the space-charge formation within the field-limiting space-charge model.

Injecting N2 to displace methane is an effective way to enhance coalbed methane drainage, and the influence radius of this process is an important factor in borehole arrangement. To determine reasonable spacing between injection boreholes and discharge boreholes, experimental and theoretical studies were carried out. The change of rule for the influence radius was determined based on the flow rate changes at the discharge boreholes when injecting gas into a coal seam in the field. Based on gas seepage-diffusion theory, a model for injecting N2 to displace coalbed methane was established. Through numerical simulation, the time characteristics of the influence radius were analyzed. The results show the following: Under different gas injection pressure conditions, the influence radius increases exponentially as injection time increases, but the rate of increase of the influence radius decreases gradually. For the same injection time, the higher the injection pressure, the wider the influence radius will be. After obtaining field results, regression analysis was applied to analyze the numerical results of gas injection at different pressures, and then, the quantitative relationship between the injection influence radius r, the injection time t, and the injection pressure p was found. According to the results calculated using this formula at an injection pressure of 0.5 MPa, the optimum spacing between boreholes was determined to be 1.5 m at the Shigang Coal Mine. The analysis of reasonable spacing between injection and extraction boreholes at different injection pressures shows that the reasonable spacing between boreholes was linearly correlated with gas injection pressures. This study has important theoretical and practical significance for the spacing between boreholes in a reasonable arrangement when injecting N2 to displace methane. [ABSTRACT FROM AUTHOR]

In this paper, a multi-relaxation time (MRT) pseudo-potential based lattice Boltzmann model is implemented to investigate the isothermal injection filling of 2D cavities with arbitrary shapes. The model is capable of handling relatively large density ratios and low viscosities. First, the model is validated by a comparison of the numerical results with those of the experiments reported in the literature for a broken dam problem where a good agreement is observed. Next, the filling process of a rectangular cavity is simulated and effects of the Reynolds and Froude numbers as well as the cavity aspect ratio are investigated. Two filling regimes namely steady and splashing are identified. The formation of gas bubbles are observed in the splashing regime while in the case of steady filling, no bubbles are trapped and the liquid jet fills the cavity smoothly. Furthermore, the threshold Re number for the onset of splashing is evaluated by changing the effective variables. It was found that this threshold Re is increased by a reduction of the cavity aspect ratio ( H / L ) less than 0.5. Decreasing the Fr number and increasing the ratio D / L also increase the threshold Re for the onset of splashing. In the next case, filling a circular cavity with a solid core is also simulated at relatively low and high Re numbers and results at a Re of 81 are compared with those of the SPH method reported in the literature. Finally, a multi-branch header discharging into eight uniform cavities is studied. It was found that the filling sequence of the branches is different for low and relatively high Re numbers. [ABSTRACT FROM AUTHOR]

Papers presented at the International Ferrous Metallurgy Conference AISTech 2017 (Nashville, USA, May, 8-11 2017) on the problem of improving the efficiency of blast furnace smelting and reducing the cost of cast iron with coal-dust fuel and natural gas injection are reviewed. [ABSTRACT FROM AUTHOR]

Blend of diesel and gasoline (Dieseline) has been proven useful to improving premixed compression ignition (PCI) combustion but it is associated with combustion instability at low load conditions. In this study, a new strategy is developed using high rate of hot-EGR and lower injection pressure for the combustion control. The viability and benefits of PCI using the new strategy are evaluated with the low cetane-number (<30) and wide boiling range G75-Dieseline (a blend of 75% gasoline in diesel based on volume). Experiments were conducted on a light-duty 4-cylinder CI engine with 15.5 compression ratio and at 1.4 and 3 bar BMEP. Different fuel injection and intake/exhaust handling strategies were investigated, and the results concerning combustion performance and emission characteristics were compared to those obtained when using diesel fuel at the same operating loads as the baselines. Utilising the hot-EGR strategy as an incentive to increase the intake temperature and lower fuel injection pressure to reduce overmixing and fuel wall-impingement are necessary for PCI combustion of volatile and low cetane-number fuels at lower engine operating loads. Oxides of nitrogen and smoke emissions were decreased by up to 99% while maintaining similar range brake thermal efficiency compared to diesel combustion. [ABSTRACT FROM AUTHOR]

A better understanding on the effects of fuel properties and injection timing is required to improve the performance of advanced engines based on low temperature combustion concepts. In this work, an experimental and computational study was conducted to investigate the effects of physical and chemical kinetic properties of low octane fuels and their surrogates in partially premixed compression ignition (PPCI) engines. The main objective was to identify the relative importance of physical versus chemical kinetic properties in predicting practical fuel combustion behavior across a range of injection timings. Two fuel/surrogate pairs were chosen for comparison: light naphtha (LN) versus the primary reference fuel (PRF) with research octane number of 65 (PRF 65), and FACE (fuels for advanced combustion engines) I gasoline versus PRF 70. Two sets of parametric studies were conducted: the first varied the amount of injected fuel mass at different injection timings to match a fixed combustion phasing, and the second maintained the same injected fuel mass at each injection timing to assess resulting combustion phasing changes. Full-cycle computational fluid dynamic engine simulations were conducted by accounting for differences in the physical properties of the original and surrogate fuels, while employing identical chemical kinetics. The simulations were found to capture trends observed in the experiments, while providing details on spatial mixing and chemical reactivity for different fuels and injection timings. It was found that differences in physical properties become increasingly important as injection timing was progressively delayed from premixed conditions, and this was rationalized by analysis of mixture stratification patterns resulting from injection of fuels with different physical properties. The results suggest that accurate descriptions of both physical and chemical behavior of fuels are critical in predictive simulations of PPCI engines for a wide range of injection timings. [ABSTRACT FROM AUTHOR]

A prototype of a continuous injection direct rolling (CIDR) imprint system was developed and applied to CIDR tests to evaluate its feasibility for the large-area replication of an optical micro device. The developed system adopts the theories of injection compression and thermal imprinting and presents the capacity to fabricate a 200 mm-wide and over 10 m-long PMMA plate and to replicate ultra-precision structures on its surface at a rolling speed range of 1.1-11.5 mm/s. Under the given CIDR conditions (injection temperature, 280 °C; injection pressure, 6 MPa; rolling force, 13 MPa; roller temperature, 85 °C), complete fabricating of a 0.7 mm-thick Polymethyl methacrylate (PMMA) plate with 17.3 μm-deep and 35 μm-wide V-groove microstructures was achieved at a rolling speed of 3.4 mm/s. Finally, a light guide plate for a backlight panel was fabricated by CIDR. The light transmittance of this plate reached 90.8 %, the maximum birefringence was ~99 nm and its average haze was 0.51 %. [ABSTRACT FROM AUTHOR]

To extend the scope of fuel types used in iron making process, the possibilities to utilize semi-coke as injected fuel for blast furnace and alternative fuel for sintering were studied comprehensively. Both the basic properties (proximate and ultimate analysis) and technological properties (grindability, explosivity, fluidity, igniting temperature, calorific value, etc.) were analysed and compared with traditional fuels used in the pulverized coal injection and sintering processes. Furthermore, the results of industrial application confirmed the technological and economical advantages to utilize semi-coke in those two processes. [ABSTRACT FROM AUTHOR]

This study evaluates the risk for CO2 leakage from a storage site using a risk assessment criterion, the safety index, which considers the contributions of residual gas, solubility, ionic, and mineral trapping mechanisms. We present a case of CO2 storage in a deep saline aquifer in Yutengping (YTP) sandstone, Tiehchanshan (TCS) field, Taiwan. The numerical method was used to estimate the amount of different CO2 phases sequestered by the various trapping mechanisms. The CO2 injection rate was 1 million tons per year for 20 years. The total simulation time was 1000 years. In the case of down-dip well injection, the safety index was 0.77 at the storage time of 1000 years and much higher than the safety index of 0.45 for the up-dip well. More mobile supercritical CO2 had to be sealed using a caprock in the up-dip well injection case. Injecting CO2 using a down-dip well is a better engineering strategy because the safety index is higher. [ABSTRACT FROM AUTHOR]

Jet grouting is a known ground improvement technique largely used worldwide for different applications. One of the major limitations of this technique is mainly related to obtaining good predictions of the geometry of the final grouted body, as it is a function of the injection parameters and soil properties. Over the years, many studies have been conducted and few models and design methodologies have been developed to obtain more accurate predictions. A short review on some models found in the literature with a theoretical background is provided in this paper, highlighting the advantages and the limitations of each approach presented. A brief overview on emerging approaches is presented as well. [ABSTRACT FROM PUBLISHER]

In order to reduce the cost of microbial-induced carbonate precipitation, an in situ soil improvement technique, two cost-effective methods have been developed. At first, possible replacement of costly yeast extract medium with sodium acetate for Sporosarcina pasteurii growth was evaluated. Thereafter, a sequencing batch mode of injection has been introduced. The unconfined compressive strength of 525 kPa with uniform CaCO3 distribution was obtained even for poorly graded coarse sand using the proposed injection method. According to economic considerations, by using this injection method, a substantial cost saving (53.4%) has been achieved, inducing the feasibility of biocementation technology for practical applications. Copyright © 2016 Curtin University of Technology and John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Similar quantitative relations between individual constituents of the liquid sample established by its direct injection can be obtained applying Polydimethylsiloxane (PDMS) fiber in the headspace solid phase microextraction (HS-SPME) system containing the examined sample suspended in methyl silica oil. This paper proves that the analogous system composed of sample suspension/emulsion in polyethylene glycol (PEG) and Carbowax fiber allows to get similar quantitative relations between components of the mixture as those established by its direct analysis, but only for polar constituents. It is demonstrated for essential oil (EO) components of savory, sage, mint and thyme, and of artificial liquid mixture of polar constituents. The observed differences in quantitative relations between polar constituents estimated by both applied procedures are insignificant (F exp < F crit ). The presented results indicates that wider applicability of the system composed of a sample suspended in the oil of the same physicochemical character as that of used SPME fiber coating strongly depends on the character of interactions between analytes-suspending liquid and analytes-fiber coating. [ABSTRACT FROM AUTHOR]

Weathered crust elution-deposited rare earth ores are rich in the middle and heavy rare earths. The present study investigated the content of exchangeable aluminum and the exchangeable rare earth in the different layer of orebody and the partitioning of rare earth was determined as well to understand the mode of occurrence of rare earth. Furthermore, the swelling of clay minerals from different layers was investigated. The results shown that, in completely weathered layer and partly weathered layer, the content of exchangeable rare earth was more than 0.06% and the content of exchangeable aluminum was below 0.02%. However, in humic layer, the content of exchangeable rare earth was below 0.015% and the exchangeable aluminum was more than 0.03%. In the weathered crust elution deposited rare earth ore, the exchangeable aluminum is mainly found in the humic layer, whereas the rare earth elements are abundant in the completely weathered layer and partly weathered layer and the rare earth in humic layer belong to light rare earth group. Additionally, the swelling of clay minerals in humic layer was ranged between 2.5% and 2.7%, which were higher than the swelling of clay minerals in completely weathered layer and partly weathered layer. Based on these findings, a novel in-situ leaching technology of weathered crust elution-deposited rare earth ores is proposed. The leaching agents were directly injected into the completely weathered layer without infiltrating through the humic layer. Avoiding the humic layer, only the completely weathered layer and partly weathered layer were leached. According to this method, the exchangeable aluminum in the rare earth leaching solution can be decreased and the purity of rare earth product can be improved. Meanwhile, the ammonium chloride was alternatively applied to leach rare earth and the choices of available leaching reagents were broadened. [ABSTRACT FROM AUTHOR]

It is important to study the CO2 corrosion behavior in CCS operation, which applies CO2 injection. In oil and gas exploration and production environments, reservoirs may contain acidic gases such as CO2, and corrosion environments become harsh for OCTG and line pipes. In this paper, research work on CO2 corrosion and countermeasures against it is reviewed. CO2 corrosion can be characterized by its relatively high corrosion rate and localized corrosion (ringworm corrosion). It is also recognized that the corrosion behavior depends on such environmental factors as CO2 partial pressure and temperature; as well, the effect of flow velocity is appreciable. The addition of Cr as an alloying element is effective in mitigating CO2 corrosion; therefore, stainless steels such as Super 13Cr have been widely applied as OCTG and line pipes. [ABSTRACT FROM AUTHOR]

In this study, a kerosene-fueled high-velocity thermal spraying model is used to examine the flame and particle behavior in a thermal spray process. The gas flow characteristics (including temperature, velocity, and pressure), mass fraction of the gas components, and the particle characteristics (including the particle temperature, velocity, and in-flight trajectory) are successfully simulated. Besides, the effects of particle diameter, particle shape, and particle injection velocity on the particle behavior in the spraying flame are also investigated. The optimal particle size range is found to be between 20 and 40 μm. In this case, most of the particles are located towards the center of the gun and are in a semi-solid state before impacting the substrate. When the shape factor falls from 1 to 0.6, the non-spherical particles gain more momentum and less heat than spherical particles in the process owing to their higher drag coefficient and shorter dwell time within the flame flow. A comprehensive consideration of the injection velocity on the spray particle dynamics revealed that the optimal particle injection velocity should be greater than 5 m/s but no more than 20 m/s. [ABSTRACT FROM AUTHOR]

For the gas flood process, crude oil physical properties including oil volume and viscosity would be greatly changed resulting from gas solution and extraction. First, solubility of natural gas in oil and brine was measured and compared. Meanwhile, the resulting oil expansion and viscosity reduction were experimentally tested. Second, oil viscosity increase due to extraction was studied by extraction experiments. Finally, oil recovery of natural gas and propane-enriched natural gas flood was studied under different pressures. Results show that solubility of natural gas in oil is dozens of times of that in brine. Variation of crude oil physical properties during natural gas injection mainly includes the remarkable volume expansion and viscosity reduction caused by gas dissolution into oil, and the oil volume shrinkage and viscosity increase caused by extraction are not so significant. The oil recovery of natural gas flood grows linearly with increased injection pressure and gas solubility in oil, but is still less than 90% even at 55 MPa, which indicates immiscible flood at 55 MPa. Addition of propane to natural gas is proved to be helpful for enhancing oil recovery and achieving miscibility. [ABSTRACT FROM AUTHOR]

Mn doped Ag-In-Zn-S nanoparticles (Mn:AgInZnS) were successfully synthesized by using a practical hot-injection method. The as-prepared Mn:AgInZnS nanoparticles were triangular shape with average radius of 6(± 0.5) nm, and the composition of doped Mn was about 7.29 by wt.%. Moreover, the Mn:AgInZnS nanoparticles demonstrated strong and stable photoluminescence emission at about 620 nm, and the UV-vis absorption spectrum further revealed band gap absorption around 600 nm. Furthermore, the photoluminescence lifetime of Mn:AgInZnS nanoparticles was about 1.38 µs which indicated the tremendous potential applications in cell labelings, fluorescent imaging, solar cells and LEDs. [ABSTRACT FROM AUTHOR]

In this paper, Al 2 O 3 –Cr 2 O 3 composite coating was fabricated by plasma spraying. It has better mechanical performances than Al 2 O 3 coating. Erosion–wear resistance of the coatings was evaluated by a new type of solid particle impact test (slurry jet). Slurry was mixed with compressed air in the nozzle and eventually injected on coating surface at high velocity. Injected slurry on coating surface resulted in a wear progression (wear rate) proportionately to the erosion strength of the coating material. Al 2 O 3 –Cr 2 O 3 composite coating possesses better erosion–wear resistance than pure Al 2 O 3 coating. [ABSTRACT FROM AUTHOR]

Degradable fiber can temporarily plug a natural fracture or artificial fracture. It has been successfully applied in the stimulated reservoir volume (SRV) fracturing or re-fracturing of unconventional reservoirs. Based on the classical analytical stress field equation, a new mathematical model is established in this paper to model the crack reorientation path after injecting fiber diversion fluid according to the tensile failure criterion. Factors influencing the diverting radius are intensively analyzed through numerical simulation. The results indicate that the horizontal stress difference, fracturing fluid viscosity, and injection time (fracturing fluid volume) have larger effects on the diverting radius than do the formation permeability (1–50 mD) and bottomhole pressure (90–160 MPa). The simulation results are successfully verified, matching well with the experimental data from the true tri-axial fracture reorientation tests in the laboratory. The model is successfully applied to the heterogeneous carbonate reservoirs in northwest China. [ABSTRACT FROM AUTHOR]

Reverse recovery behavior of semiconductor power diode is usually involved in the operation of electrical equipment, which is mainly determined by the internal factor and external circuit of the device. In the present paper, the spatial-temporal distribution of minority carriers (MCs) in base region (BR) and waveforms of current and voltage in reverse recovery of p-n-n type 4H-SiC diode were numerically probed via an analytical model with injection conditions, of which parameters such as diffusion coefficient and length depend on the concentration of injection carriers. The storage time and the recovery time were evaluated. The results indicate that the current and voltage transient characteristics in reverse recovery process are affected by the width, concentration of majority carriers and lifetime of minority carriers in base region, also by the doped levels in anode and cathode, as well as by the forward current density and reverse biased voltage at initial state. The characteristic frequency was also influenced by these factors. These obtained consequences could guide for device optimized design and application. [ABSTRACT FROM AUTHOR]

MgO-doped lithium niobate that is simultaneously congruent and stoichiometric, denoted cs-MgO:LN (Li 2 O:Nb 2 O 5 :MgO=45.3:50.0:4.7) [1] , has a partition coefficient of unity for each of its constituent species, including ionic species. As such, this material exhibits no segregation of ions during crystal growth. However, a crystallization electromotive force (c-EMF) is observed during growth by the micro-pulling down (μ-PD) method, due to segregation of the cs-MgO:LN ionic species. This arises from a steep temperature gradient at the solid–liquid interface that generates an electric field due to the Seebeck effect. In this case, the equilibrium partition coefficient, k 0 , must be modified to k E0 to take into account the effect of an electric field on the partitioning of ionic species. A coefficient of k E0 rather than k 0 has a value of non-unity and therefore can lead to generation of a c-EMF. An electric current was injected into the melt in such a way that the Seebeck effect was canceled, and this demonstrated that the value of k 0 is unity for all constituent ionic species of cs-MgO:LN. It has thus been confirmed that an injected electric current reduces the c-EMF. Only cs-MgO:LN attained a zero c-EMF value at a specific current that was valid at all growth rates, whereas s-MgO(2.5 mol%):LN and ZnO-doped LN required velocity-dependent currents to reduce their c-EMFs to zero. The observation of a zero c-EMF at all growth rates upon removing the Seebeck field effect indicates that the value of k 0 is unity for all constituent species of cs-MgO:LN in both the melt and crystal phases, including ionic species. Therefore, the activity of all components of cs-MgO:LN in both phases is unity and this compound is simultaneously stoichiometric and congruent. [ABSTRACT FROM AUTHOR]

An alternative energy technology to save power consumption in the steelmaking process was developed with supplementary oxygen injection in a new shaft electric arc furnace (EAF). The optimisation of oxygen injection for enhancing post-combustion was carried out to increase the preheating temperature of the scrap in the shaft using preheating simulation and trial tests. The conditions of oxygen injection from supersonic burners and an oxygen lance, and the appropriate injection distance between molten bath and oxygen lance, were established through fluid flow simulation and practical tests. In addition, the optimal conditions for supersonic burners and oxygen injection to enhance the post-combustion were deduced. From comparisons of the present and conventional results, it was found that the electric energy and operating time of the shaft EAF were decreased through practical improvements, resulting in energy savings and increase in productivity on the shaft EAF. [ABSTRACT FROM AUTHOR]

Inverted transparent organic light-emitting diodes (i-TOLEDs) were fabricated using thermal evaporation and spray methods. Only oxide compounds were used for the electron injection layer (EIL) of the diodes, and no alkali metals were included. Furthermore, these i-TOLEDs were fabricated with a nanoscale metal/dielectric multilayered transparent conductive film, which served as the anode. [ABSTRACT FROM AUTHOR]

Highlights: [•] Fluid flow in a PS converter with three injection points is described. [•] Plume features with three injection points are described. [•] Bubbling to jetting transition is represented by the Kutateladze number. [Copyright &y& Elsevier]

As the large thin-walled and hollow investment casting is widely used, control of core deflection during wax injection becomes increasingly important. Core deflection during wax injection can cause wall thickness to exceed tolerance in final cast part. This paper presents the numerical and experimental study on the core deflection of a thin-walled hollow wax pattern. The predicted deflection displacements were compared with the experimental data to find good agreement. The mechanism of core deflection was found through 3D numerical analysis. The packing pressure differentials in packing phase are the major cause for core deflection during wax injection, which can be reduced by low packing pressures. The results show that more fixed core-pins can also reduce the thickness variation in the two sides of the thin-walled wax pattern. In this study, the core deflection during wax injection was successfully modeled, which will significantly help to understand the core deflection behavior in complex geometries during injection molding. [ABSTRACT FROM PUBLISHER]

Despite recent advances in numerical modeling of machining processes showing a significant potential for shortening product and process design activities, the broader application of the Finite Element Method (FEM)–based modeling approaches in the manufacturing industry is still limited by the expensive and time-consuming techniques involved in obtaining accurate material flow stress data. This study proposes a new efficient approach consisting of a combined numerical-empirical methodology for inversely identifying the thermomechanical material behavior ofAISI 316Lstainless steel from machining experiments. In order to establish the work material's flow stress properties under the extreme conditions of machining, the Johnson–Cook (JC) constitutive equation is chosen to consider the impacts of strain, strain-rate, and temperature. Due to the unstable material behavior ofAISI 316Lstainless steel under certain thermomechanical conditions in the primary shear zone, the calibration of a damage model is integrated into the process for evaluating the flow stress data. The methodology approximates the material constants of the JC relationship by systematically comparing experimentally measured machining results with those predicted equivalents of a 2D implicit FEM process model. The methodology is experimentally verified onAISI 316Lstainless steel with respect to cutting forces, chip geometries and temperatures in the tool-chip interface. [ABSTRACT FROM PUBLISHER]

Liquid silicone rubber is an interesting material at an industrial level, but there are great difficulties in the design and machining of molds, and in addition, it cannot be processed using conventional equipment. Therefore, new lines of research have focused on the search for new materials capable of providing final properties similar to liquid silicone rubber, that can also be engineered using simple, conventional processes and machinery. In this investigation, a range of compatible blends, based on two commercial grades of styrene-b-ethylene-co-butylene-b-styrene (SEBS) thermoplastic elastomer, was studied in order to obtain a range of different Shore A hardness blends for industrial applications where liquid silicone rubber (different hardness) is currently used. The two blended elastomers used had widely differing Shore A hardness values (5 and 90). Once the blended materials had been characterized, the Cross and Williams et al. [20] (Cross-WLF) mathematical model was applied in order to obtain theoretical performance curves for the viscosity of each of the blends. After this, a model was developed using the Computer Aided Engineering (CAE) software package Autodesk Moldflow 2012™. This computer modeling validated the results obtained from the mathematical models, thus making available to process engineers the full range of hardnesses necessary for industrial products (where liquid silicone rubber is used), while still providing the advantages of thermoplastic injection molding. [ABSTRACT FROM PUBLISHER]

This letter investigates the degradation behavior under hot-carrier stress in InGaZnO thin film transistors with I- and U-shaped asymmetric electrodes. After hot-carrier stress, a serious Vt shift, as well as on-current and subthreshold swing degradations are observed in Id-Vg transfer curve under reverse mode. Moreover, it is found that the Vt instability is caused by hot-electron injection near the drain side, and this phenomenon which is verified by C-V measurement. Furthermore, the location of trapped hot-electron is estimated from the two-stage rise in the gate-to-drain/gate-to-source capacitance curves and then verified by the simulation tool. [ABSTRACT FROM AUTHOR]

Highlights: [•] Numerical simulations examine potential performance of microhole-based EGS. [•] Injection of working fluid through microhole array may increase heat mining efficiency. [•] Microhole-based EGS is more robust to uncertainty in rock properties. [Copyright &y& Elsevier]

The article offers information on the results obtained by coreflood experiments carried out in a core under natural water-wet conditions including water injection, gas injection and water-alternating-gas injection used for oil recovery. It informs that WAG injection performs better than water injection and gas injection. It also mentions that oil recovery by gas injection is considerably higher than water injection in the water-wet system but lower in the mixed-wet system.

Abstract: Al356/5vol.% SiCp cast composites were fabricated by the injection of reinforcement particles into the melt in three different forms, i.e. as untreated SiCp, milled particulate Al–SiCp composite powder, and milled Al–SiCp–Mg composite powder. The resultant composite slurries were then cast in the semisolid temperature range of the alloy, upon which the effects of the type of injected powder on the distribution and incorporation of the reinforcement particles, along with the hardness of the cast composites, were investigated. Injection of milled composite powders resulted in considerable improvement in SiCp wetting as well as the incorporation and distribution of SiCp in the Al356 matrix alloy. Al356/5vol.% SiCp composite with well dispersed reinforcement particles of less than 3μm average diameter was successfully produced by injecting Al–SiCp–Mg composite powder into the melt. The best microstructural characteristics in terms of the reinforcement incorporation and distribution, and the highest hardness value of the cast composites, were achieved when magnesium was added through the injected composite powder and not directly into the melt. [Copyright &y& Elsevier]

Toward higher efficiency and lower emissions, modern direct injection (DI) engines employ various injection strategies. This leads to more complex in-cylinder spray evaporation and combustion processes, requiring more comprehensive modeling approaches. In this study, an extended flamelet model is developed to describe DI engine combustion over a wide range of injection timings. A key feature of the model is to fully incorporate the interaction between spray evaporation and gas-phase combustion. Additional source terms representing the effect of evaporation were incorporated in the flamelet equation solved in the reactive space. A simple test problem demonstrated that the new formulation successfully accounts for the history of the spray evaporation. The extended formulation was implemented into a multidimensional computational fluid dynamics (CFD) code KIVA3v for full cycle engine simulation. The modeling results were successfully validated against available experimental data obtained from a rapid compression facility. [ABSTRACT FROM AUTHOR]

Abstract: The copper thin films were deposited by an alternating injection of Cu(ethylketoiminate)2 and H2, and the effects of substrate temperature on the atomic layer deposition and the properties of the deposited thin film were investigated. Continuous films with a small sheet resistance were obtained at a deposition temperature of 140°C. The sheet resistance and the surface roughness increased with increasing deposition temperature due to the agglomeration of copper. The growth rate at 140°C was 0.12nm/cycle, with a copper precursor exposure greater than 1.0×107 L and H2 exposure greater than 3.0×108 L. [Copyright &y& Elsevier]

Abstract: In this paper, the cyclic variation characteristics of a hydrogen-enriched gasoline engine under various operating conditions were experimentally investigated. The test was carried out on a modified four-cylinder gasoline engine equipped with an electronically controlled hydrogen injection system. A hybrid electronic control unit was developed to govern the injection timings and durations of hydrogen and gasoline to accomplish the on-line adjusting of the hydrogen blending level and excess air ratio. The engine was first run at idle condition with an idle speed of 790 rpm and then operated at 1400 rpm to investigate the cyclic variation in a hydrogen-blended gasoline engine at different hydrogen volume fractions in the total intake, excess air ratios, spark timings and manifolds absolute pressures. The test results demonstrated that the coefficient of variation in indicated mean effective pressure was distinctly decreased with the increase of hydrogen blending ratio. At 1400 rpm and a manifolds absolute pressure of 61.5 kPa, the relevant excess air ratio for the engine lean burn limit was extended from 1.45 to 2.55 when the hydrogen volume fraction in the intake was raised from 0% to 4.5%. Besides, for a specified hydrogen addition level, the coefficient of variation in indicated mean effective pressure was continuously increased but the coefficient of variation in the peak cylinder pressure was first raised and then decreased with the increase of excess air ratio. The experimental results also showed that hydrogen addition was more effective on reducing engine cyclic variation at low loads rather than at high loads. [Copyright &y& Elsevier]

Abstract: In computer assisted optimization of liquid chromatography it has been known for some years that it is important to use experimental injection profiles, instead of rectangular ones, in order to calculate accurate elution bands. However, the incorrectly assumed rectangular profiles are still mostly used especially in numerical optimizations. The reason is that the acquisition of injection profiles, for each injection volume and each flow rate considered in a computer-assisted optimization requires a too large number of experiments. In this article a new function is proposed, which enables highly accurate predictions of the injection profiles and thus more accurate computer optimizations, with a minimum experimental effort. To model the injection profiles for any injection volume at a constant flow rate, as few as two experimental injection profiles are required. If it is desirable to also take the effect of flow rate on the injection profiles into account, then just two additional experiments are required. The overlap between fitted and experimental injection profiles at different flow rates and different injection volumes were excellent, more than 90%, using experimental injection profiles from just four different injection volumes at two different flow rates. Moreover, it was demonstrated that the flow rate has a minor influence on the injection profiles and that the injection volume is the main parameter that needs to be accounted for. [Copyright &y& Elsevier]

Abstract: Understanding and controlling charge transport are crucial to achieve optimized organic devices, including light emitting diodes. In this study, we investigate the charge injection in devices made with a hybrid composite (HC) containing Zn2SiO4:Mn (ZSP:Mn) in a polymeric blend consisting of poly(o-methoxyaniline) (POMA) and poly(vinylidene co-trifluorethylene) P(VDFTrFE), with the architecture ITO/HC/metallic electrode (ME). Charge injection was found to depend mainly on the POMA semiconducting phase. For ITO/HC/Au, an Ohmic junction was observed because the work function of ITO is close to that of Au, which also matches the energy levels of HC. Holes are injected through the HC/Au junction, as the highest occupied molecular orbital (HOMO) level of POMA matches the Fermi level of Au. The impedance spectroscopy data for the ITO/HC/ME devices were analyzed with a theoretical model where charge injection was assumed to occur via hopping with a distribution of potential energy barriers. The average hopping distance was estimated as 5.5Å and only the device with the Al electrode had the current limited by the interface mechanism (charge injection). For ITO/HC/Cu and ITO/HC/Au devices the limiting factor for the charge transport was the bulk resistance of the samples, in spite of the existence of a small interface energy barrier. The disorder parameter was 0.18 and 0.19 for the HC/Cu and HC/Al interfaces, respectively, which arises from the disordered nature of the hybrid material. The combination of the Cole–Cole model and the Miller–Abrahams function are a good approach to describe charge a.c. injection processes in disordered materials. [Copyright &y& Elsevier]

The non-local spin injection in lateral spin valves is strongly expected to be an effective method to generate a pure spin current for potential spintronic application. However, the spin-valve voltage, which determines the magnitude of the spin current flowing into an additional ferromagnetic wire, is typically of the order of 1??V. Here we show that lateral spin valves with low-resistivity NiFe/MgO/Ag junctions enable efficient spin injection with high applied current density, which leads to the spin-valve voltage increasing 100-fold. Hanle effect measurements demonstrate a long-distance collective 2? spin precession along a 6-?m-long Ag wire. These results suggest a route to faster and manipulable spin transport for the development of pure spin-current-based memory, logic and sensing devices. [ABSTRACT FROM AUTHOR]

Abstract: The geometries, frontier molecular orbitals, charge injection and transfer, as well as spectroscopic properties of a series of novel bis(8-hydroxyquinolinato) (Ptq2) derivatives with oligothiophenes moiety were investigated theoretically. The calculated results indicated that incorporating of oligothiophene units into the Ptq2 had major role in the tailoring the optical properties. Furthermore, from the analyses of ionization potentials (IP), electron affinity (EA), reorganization energy (λ), it was found that these Pt derivatives have excellent hole and electron injection and transfer ability by introducing the oligothiophenes at the 7-positions of the quinoline ligand. These results are favorable to establish the structure–photophysical property relationship for enhancing the carrier transfer abilities of Ptq2. [Copyright &y& Elsevier]

mathematical model is proposed for the process of injection of material from a two-component sample of limited weight into a discharge plasma in atomic emission spectral analysis. An analytical expression is obtained for the time dependence of the intensity of the spectral line for the element associated with a small impurity. It is shown that based on the ratio of the volatility factors for the impurity material and the matrix, three groups of analyte elements can be isolated with similar injection behavior. Comparison of the theoretical and experimental results shows their qualitative agreement. [ABSTRACT FROM AUTHOR]