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Orientation-dependent induced-charge electrophoresis (ICEP) behaviors are measured in magnetic metal-coated Janus particles, where the orientation of the particle with respect to the electric field is controlled by an external magnetic field. For a thin metallic coating (10 nm), the particle mainly moves normal to the electric field without the magnetic field. The velocities of ICEP in different directions are measured under the magnetic field and clear orientation-dependent velocities are observed. However, for a thick metallic coating (70 nm), the particle mainly moves parallel to the electric field without the magnetic field and shows an opposite tendency for orientation-dependent velocities compared with the thin metallic coated particles. We propose that the strength of the induced dipole of a Janus particle depends on the thickness of the metallic coating, which results in different orientation-dependent velocities of the Janus particle under electric fields.

This article provides a simple method to prepare partially or fully coated metallic particles and to perform the rapid fabrication of electrode arrays, which can facilitate electrical experiments in microfluidic devices. Janus particles are asymmetric particles that contain two different surface properties on their two sides. To prepare Janus particles, a monolayer of silica particles is prepared by a drying process. Gold (Au) is deposited on one side of each particle using a sputtering device. The fully coated metallic particles are completed after the second coating process. To analyze the electrical surface properties of Janus particles, alternating current (AC) electrokinetic measurements, such as dielectrophoresis (DEP) and electrorotation (EROT)- which require specifically designed electrode arrays in the experimental device- are performed. However, traditional methods to fabricate electrode arrays, such as the photolithographic technique, require a series of complicated procedures. Here, we introduce a flexible method to fabricate a designed electrode array. An indium tin oxide (ITO) glass is patterned by a fiber laser marking machine (1,064 nm, 20 W, 90 to 120 ns pulse-width, and 20 to 80 kHz pulse repetition frequency) to create a four-phase electrode array. To generate the four-phase electric field, the electrodes are connected to a 2-channel function generator and to two invertors. The phase shift between the adjacent electrodes is set at either 90° (for EROT) or 180° (for DEP). Representative results of AC electrokinetic measurements with a four-phase ITO electrode array are presented.

A method for fabricating a microlens array composite optical film by a seamless roller mold of self-assembly is presented. The roller with a lot of random cavities is used to produce a polyethylene terephthalate (PET) composite optical film with 3D random microlens arrays using the ultraviolet (UV) roll-to-roll printing. The luminance gain and haze are 1.247 and 86 %, respectively, giving the PET composite optical film the properties of a brightness enhancement film and a diffuser. Solid glass beads (SBs) are used for parameter testing for self-assembly. Then, 3 M glass bubble beads (BBs) are used to fabricate a seamless roller mold. The optimal parameters of the self-assembly process for the SB are a coating speed of 135 mm/h with a 39 % volume ratio, and those for the BB are a coating speed of 30 mm/h with a 3 % volume ratio. Finally, the PET optical film is used in the green energy lighting testing of a commercial bicycle light-emitting diode (LED). The results show increased lighting angle and light uniformity, making it similar to traditional tungsten light.

The paper studies the principle and the flaw of the hydraulic control organization of concrete mixer truck, and designs one kind of brand-new Digital Display control devise. According to principle of the new Digital Display control devise, it has determined shifting block’s displacement quantity and the displacement limit of the key component of unloading Control devise. At the same time, the design has realized the accelerograph’s control device, and compared with the merit and demerit between the new and old control devise based on the basis of the practice application.

The paper introduces the surge phenomenon of the axial-flow compressor. To ensure the blower running safely, we analyze the surge phenomenon and design a anti-surge control system by using the fuzzy control theory to control the position of the snorting valve. The result of simulation in Matlab proves that the fuzzy controller is feasible.

The paper discusses the principles and shortcomings of the concrete mixer truck’s hydraulic control mechanism. The stepper motor technology controlled by the electrical impulses is used to develop a new digital display control device, and determine design principle and implementation process of the electronic control part. At the same time, it develops control device’s digital display mechanism and wireless remote control devices. At last, it compares the performance advantages and disadvantages between the traditional mechanical control handler and the digital display remote controller according to the engineering practice.

This paper briefly describes the importance of coiling temperature control in the strip production process, and analysis which shows that the current existence of coiling temperature control is difficult, for the laminar cooling process is one with a strong non-linear, distributed parameter, time-varying. Intelligent control method is presented and carried out with the Matlab simulation. The simulation result shows that this method will enable the ultimate precision of coiling temperature control within 5 °C.

This investigation explores the deformation and annealing behaviors of high-entropy alloys using a ductile high-entropy alloy of Al0.5CoCrCuFeNi. This alloy had excellent workability and exhibited a large work hardening capacity in both hot forging and cold rolling. The main deformation and hardening mechanisms during cold work are uniquely associated with the nanotwinning deformation of this alloy. The easy formation of nanotwins appears to result from the blockage by the Widmanstatten Cu-rich precipitates of local slip deformation in a space of several tens nanometers, and the low stacking fault energy, which promotes the nucleation of nanotwins. This alloy was fully annealed in 5 h at 900 °C, revealing its significantly higher resistances to static anneal softening than traditional alloys with comparable melting points. This resistance is attributable to extensive solution hardening, low stacking fault energy, and the effect of sluggish diffusion on high-entropy alloys.

The competition between the constituent elements of the Cu 0.5 NiAlCoCrFeTiMo alloy system during mechanical alloying was investigated and ranked with their alloying rates in getting alloyed in the mixture. By using XRD analysis, EDS mapping, extended X-ray absorption fine structure technique, and synchrotron radiation diffraction, the alloying sequence for the present alloy system is determined as Al → Cu → Co → Ni → Fe → Ti → Cr → Mo in the order of decreasing alloying rate. The alloying rate is found to correlate best with the melting point of the elements among metallurgical factors. The mechanism for this correlation is explained through the effect of melting point on solid-state diffusion and mechanical disintegration which are critical for the final alloying. This finding is valuable in predicting the alloying sequence of elements, and thus the phase evolution in multi-component alloys during mechanical alloying.

A high-entropy alloy (HEA) has been defined by us to have at least five principal elements, each of which has an atomic concentration between 5% and 35%. In the exploration on this new alloy field, we find that HEAs are quite simple to analyze and control, and they might be processed as traditional alloys. There exist many opportunities to create novel alloys, better than traditional ones in a wide range of applications. In this paper, we review the basic microstructural features of HEAs and discuss the mechanisms of formation. Instead of multiple intermetallic phases, the HEAs tend to form simple solid solution phases mainly of cubic crystal structure, especially at elevated temperatures. This tendency is explained by the high entropy effect based on the simple relation: (Gmix = (Hmix – T(Smix, and the second law of thermodynamics. Moreover, nanostructures and amorphous phases are easily formed in HEAs. This tendency is explained by kinetics theory as due to slow atomic diffusion.

A new approach for the design of alloy systems with multiprincipal elements is presented in this research. The Al x CoCrCuFeNi alloys with different aluminum contents (i.e., x values in molar ratio, x=0 to 3.0) were synthesized using a well-developed arc-melting and casting method. These alloys possessed simple fcc/bcc structures, and their phase diagram was predicted by microstructure characterization and differential thermal analyses. With little aluminum addition, the alloys were composed of a simple fcc solid-solution structure. As the aluminum content reached x=0.8, a bcc structure appeared and constructed with mixed fcc and bcc eutectic phases. Spinodal decomposition occurred further on when the aluminum contents were higher than x=1.0, leading to the formation of modulated plate structures. A single ordered bcc structure was obtained for aluminum contents larger than x=2.8. The effects of high mixing entropy and sluggish cooperative diffusion enhance the formation of simple solid-solution phases and submicronic structures with nanoprecipitates in the alloys with multiprincipal elements rather than intermetallic compounds.

A novel method called Reciprocating Extrusion is exploited to realize the high potential of Mg-15Al-1Zn alloy to exhibit superior mechanical properties and superplasticity, bypassing the costly and complicated RS+PM route. Such refined alloys exhibit unique high-strain-rate superplasticity at 325 °C and maximum elongation larger than 1610% at 1×10 -2 s -1 . They also possess greater strength/density than 7075-T736 Al alloys.

In view of energy shortage and air pollution, ethanol-gasoline blended fuel used for motorcycle engine was studied in this work. The emissions of carbon monoxide (CO), nitrogen oxides (NO(X)) and engine performance of a 125 cc four-stroke motorcycle engine with original carburetor using ethanol-gasoline fuels were investigated. The model of three-variable Box Behnken design (BBD) was used for experimental design, the ethanol blend ratios were prepared at 0, 10, 20 vol%; the speeds of motorcycle were selected as 30, 45, 60 km/h; and the throttle positions were set at 30, 60, 90 %. Both engine performance and air pollutant emissions were then analyzed by response surface method (RSM) to yield optimum operation parameters for tolerable pollutant emissions and maximum engine performance. The RSM optimization analysis indicated that the most suitable ethanol-gasoline blended ratio was found at the range of 3.92-4.12 vol% to yield a comparable fuel conversion efficiency, while considerable reductions of exhaust pollutant emissions of CO (-29 %) and NO(X) (-12 %) when compared to pure gasoline fuel. This study demonstrated low ethanol-gasoline blended fuels could be used in motorcycle carburetor engines without any modification to keep engine power while reducing exhaust pollutants.

Biodiesel is a renewable alternative fuel produced from a wide range of vegetable oils and animal fats for use in compression ignition engines. It is rapidly expanding around the world, making it imperative fully to understand the impacts of biodiesel on the diesel engine combustion process and pollutant formation. Biodiesel can blend with diesel in any ratio, and the air pollutant emissions decreased with biodiesel content in fuels. However, biodiesel blend fuel reduced the diesel engine power output. Blend fuels containing 10, 20, 30, and 40% by volume of soybean biodiesel were used. ECOM-AC gas analyzer was used to measure the concentrations of CO, CO2, and NOx in the exhaust gas. The sampling of exhaust gas was taken in extension section of the exhaust pipe without catalytic converter. The engine experimental results showed these exhaust emissions were reduced for biodiesel blended fuels. However, additive for biodiesel was a slight increase in oxides of nitrogen (NOx) emission. From these statistical models, there are influences of biodiesel blend ratio, engine speed and throttle position. Statistical optimization methodology was used to investigate the mutual interaction between the emissions and engine performance. In this study, the suitable biodiesel blend ratio was about 2 ~ 7 %, it was the balance between exhaust emissions and engine performance.

TiN films are prepared on low carbon steel with a titanium interlayer by reactive RF planar magnetron sputtering. The titanium interlayer is sputtered in pure argon before coating TiN. Various argon/nitrogen ratios and substrate temperatures are employed during sputtering TiN. The role of Ti interlayer in the deposited TiN/Ti/Fe system is investigated and the effects of the processing variables on the mechanical properties of the deposited TiN films are evaluated. A semi-quantitative approach is employed to modify the concentrations measured in the AES depth profile and the quantities of oxygen and carbon due to outgassing are evaluated. The hardness of TiN coating reaches HK1500 at an applied load of 1 gf where the substrate effect is insignificant. It is observed that the adhesion measurement is affected by the structural orientation of the deposited TiN films. For films with strong preferred orientation (111), the failure occurs at the coating/substrate interface. However, those with random polycrystalline structure exhibit good adhesion.

Rutting is one of the main distresses in the asphalt pavements, especially in higher summer temperatures and/or under heavy loads. Efforts were made in this study to investigate rutting failures on Jing-Zhu expressway in China to determine the cause and the source of the rutting. The characteristic of the rutting on each asphalt pavement layer were analyzed by surveying the rutting depth, excavating transverse profile sections, and boring samples in the typical sections of expressways where different degrees of rutting damage were observed. It was found that 60% of the rutting was generated by the asphalt middle course layer and the remaining 40% came from the other surface layers, which was consistent with the mechanical analysis of the asphalt pavement that showed that the shear stress in middle asphalt course layer was the highest in magnitude, under load or temperature. With the combination of the indoor rutting tests on the samples from a corresponding location of the road shoulders, the influence of the high temperature stability of each asphalt pavement layer on rutting was analyzed using the method of ANOVA (Analysis Of Variance). The results indicated that the stability of the middle course layer impacted the rutting development the most. Finally, the relationship between the RD (rut depth) and the DS (dynamic stability) of each asphalt pavement layer was established using a nonlinear regression method. The governing criterion for the DS at the bottom course asphalt mixture was studied and recommendation made based on regression analysis.

A multi-functional remote sensing system (MFRSS) integrating Radio Frequency Identification (RFID) technology with remote spectral imaging and environmental sensing was developed to enhance seedling production and management in greenhouse. Consisted of a management traceability system (also known as management resume) and an environment traceability system (also known as environment resume), a traceable production management system is highly desirable for automated operations in greenhouse. This study is the first application of RFID to an automatic greenhouse seedling production system. The advantages of the MFRSS system are twofold: First, the production management information can be made traceable by establishing passive RFID on the multi-functional remote sensing system during variable boom cruising in the greenhouse. The spectral images were acquired using a color camera and a monochrome camera with a 780 nm optical filter, with the exposure time and signal gain controlled through an IEEE-1394 interface. Secondly, an automatic exposure algorithm eliminating interferences caused by sunlight variation was developed using Matlab 6.5 and LabVIEW 7.1. The tray position data were transferred to the look up table and delivered to the water management module through a DataSocket server and wireless network. The environment-sensing sub-system, including temperature, relative humidity, and photo-quantum measurements, was developed with a PCI-6023 interface to analyze their spatial distribution in the greenhouse. Not only does the mechanism established in the present study provide a basis for developing an automatic seedling production system, the environmental factors and facility status captured by the RFID-integrated MFRSS also enable a traceable seedling production management database, which is a crucial constituent for practical applications.

This study presents a novel broadband planar balun using multiple coupled lines, which are realized easily in thick-multi-layer structures, to improve broadband characteristics compared with the conventional planar Marchand balun. Additionally, an extra shunt capacitor is added to compensate the output amplitude and phase imbalances due to inductive grounding-vias. This balun is fabricated by LTCC (low temperature co-fired ceramic) technology and miniaturized successfully to 3.2 mm times 2.5 mm times 1 mm for UWB applications (3.1-8.0 GHz). Finally, the measured results agree well with the electromagnetic (EM) simulated responses

Ausaged Fe-33Ni-3Ti and Fe-34Ni-3Ti-0.5Al austenitic alloys were transformation strengthened through sequential martensite (α′ → γ) and reverse martensitic transfor-mations. An increase in yield strength of 20 to 30 ksi (130 to 210 MPa) was obtained, leading to alloy yield strengths near 180 ksi (1250 MPa) in the ausaged and transforma-tion strengthened condition. The presence of the γ′ precipitates formed on ausaging did not radically change the nature of the shear transformation nor the morphology and sub-structure of the transformation product. The presence of the γ′ precipitates did, how-ever, have the beneficial consequence that the α′→ γ reversion could be accomplished with slow heating rates without loss of transformation strengthening. The yield strength actually increased when a slow heating rate was used, a result attributed to the success-ful pinning of transformation induced defects by the γ′ precipitates and to the occurrence of additional precipitation during heating. The efficient pinning of transformation induced defects had the further consequence that the alloys could be annealed for long periods after reversion to austenite without significant loss of strength.