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The development of economical and high-sensitive strain sensor is crucial for precise measurement of strain in industrial applications, such as bearings. During operation, bearing itself is a harsh environment, which usually has large temperature variations and large centrifugal forces. This paper presents a sawtooth MEMS capacitive strain sensor for passive telemetry in bearings. The interdigital fingers are designed into sawtooth shape to decrease the influence of centrifugal acceleration. The strain sensor chip is 4mm $\times4$ mm in size, and is fabricated by a simple SOI process. Connecting the sensitive capacitor with an inductor, an LC resonant tank is formed, and the strain signal can be read out wirelessly and passively through a readout coil. Measurement results show that, in the range of $0\sim 1000~\mu \varepsilon $ , the sensitivity of the LC strain sensor reaches 34kHz/ $\mu \varepsilon $ , and the gauge factor (GF) of the strain sensor reaches 430. The influence of thickness of adhesive layer on the strain sensitivity is investigated. When the thickness of the adhesive layer reaches $500~\mu \text{m}$ , the applied stress cannot be transferred at all. Finally, the LC strain sensor is tested on a rotating platform. The measured resonant frequency shows only 0.4% deviation under 1000m/s2 centrifugal acceleration.

This paper presents an impedance matching method for increasing the readout distance of an inductor-capacitor (LC) passive wireless sensor. When the impedance of the LC sensor system is equal to that of the measurement system, there is no reflection between the LC sensor system and the measurement system, which maximizes signal-to-noise ratio and readout distance. Complex impedance matching networks at the readout port of the LC sensor system have been analyzed and simulated. The matching capacitor at the readout port is required to change with the sensing capacitor in the LC sensor in order to maintain the same resonant frequency in both readout port and LC sensor. The matching resistor at the readout port has been analyzed and optimized. A varactor-based capacitor was inserted as the matching capacitor, which can be controlled by a DC voltage so that the resonant frequency of the readout port can be scanned within the full range of resonant frequency in the LC sensor. A capacitive humidity sensor constructed from a planar spiral inductor and an interdigital capacitor was used here to demonstrate the proposed impedance matching method. It shows that the readout distance under the impedance matching is 1.5 times as long as that without the impedance matching. The impedance matching analysis gives in-depth insight into the LC sensor system behavior, and the results presented here suggest that the impedance matching method may be utilized the long distance readout of the scaled LC sensor application based on the ${S}_{11}$ measurement.

Wireless, passive, and cost-efficient monitoring of moisture within packaged food and medicine is important to ensure their safety and freshness. This paper presents paper-based single spiral inductance–capacitance (LC) sensors and a distance-insensitive readout system. The parasitic capacitance of the single-spiral coil is used to form an LC resonant circuit with its inductance. The printing paper is utilized as a humidity sensing material. A model for the LC sensor is analyzed and compared with HFSS simulation, showing the relative error within 6.3%. Nano-silver paste for the single-spiral coil was screen printed on the printing paper. The LC sensors with 4, 6, and 8-turns coils were characterized at relative humidity levels of 15%-90%RH by a readout coil at a fixed position. Comparison shows that the 8-turn sensor has the best linearity with respect to humidity. The sensitivity and response time were measured to be 120 kHz/%RH and 60 minutes, respectively, with the hysteresis errors less than 0.9%. During the practical monitoring, the tested signal frequency will have a shift if the coil’s relative position alters. To weaken the influence of the coil’s position, a readout coil, working at the quasi-resonant with the LC sensor was utilized to enhance the readout, resulting in more stable signal. According to the experimental results, the improved readout system can restrain the frequency shift within 1.1% at a readout distance from 2–50 mm when the ambient humidity is 60%RH.

A passive inductor–capacitor (LC) wireless sensor is capable of continuous real-time detection in applications that require the sensor to be powered remotely and to occupy a small volume, such as harsh and sealed environments, where physical access is difficult. However, the previously reported sensor can only monitor one single parameter of interest at a time. Here, we report a symmetric LC topological circuit configuration that consists of two LC resonators and show that it can be used to monitor double parameters simultaneously. The symmetric LC configuration separates the resonant frequency of the two different LC resonators at the circuit networks from each other. We demonstrate the use of this configuration to detect both pressure and humidity. In our prototypes, the Polydimethylsiloxane elastomer with pyramidal microstructures was utilized to fabricate the pressure sensor, and graphene oxide was utilized to fabricate the humidity sensor. Experiments demonstrate that the sensitivity of the pressure sensor is −48.5 kHz/mmHg and the sensitivity of the humidity sensor is −67.7 kHz/%RH, showing that the sensors are independently response to pressure or humidity. Overall, this symmetric LC topological circuit configuration that consists of multiple LC resonators represents a versatile approach for multiple parameters monitoring.

Inductor-capacitor (LC) sensors utilize magnetic coupling to transfer signals to the readout coil, realizing a passive wireless working pattern. They are of high use in situations where wired connections are impossible to be established. An increasing number of demands, arising from the emerging applications in the Internet of Things and portable devices, require a simultaneous monitoring in sensors. This paper proposes a branching inductor to implement multiple resonances in a single inductor. Each branch of the inductor forms a secondary inductance, which is connected with a sensitive capacitor to work as an LC sensor. The multiple resonances in the branching inductor work in a multi-mode coupling pattern. The coupling, comprising inductive coupling, and capacitive coupling is analyzed and detected. In experiments, a double branching inductor is fabricated on PET substrate. Two sensitive capacitors for humidity and pressure, respectively, are connected to the inductor, resulting in two resonant peaks to monitor the ambient humidity and pressure level. The experimental results are decoupled to obtain final outcomes: the humidity sensor can respond from 15%RH ~ 90%RH with a sensitivity of −45.3 kHz/%RH; and the pressure sensor can work from 750 mmHg ~1000 mmHg with a sensitivity of −811.2 kHz/mmHg.

A novel N-doped magnetic covalent organic framework (N-Mag-COF) has been synthesized. It has been evaluated in the magnetic dispersive solid phase extraction (Mag-dSPE) procedure for textiles of fall protection equipment prior to the analysis of allergenic disperse dyes by liquid chromatography-tandem quadrupole mass spectrometry (LC-MS/MS). Compared with the matrix dilution procedure, much higher sensitivity of the analytical method has been achieved by the N-Mag-COF Mag-dSPE procedure. Furthermore, under the optimum conditions, the level of matrix effects can be dramatically reduced by the N-Mag-COF Mag-dSPE procedure with satisfactory recoveries in the range of 72.2–107%. The precision of the developed method was satisfactory, with relative standard deviations (RSDs) ranging from 2.3% to 7.1%. The limits of detection (LODs) and limits of quantification (LOQs) of 19 allergenic disperse dyes were in the range of 0.021–0.58 μg kg−1 and 0.069–1.91 μg kg−1, respectively. The developed analytical method was successfully applied to the analysis of 20 textile samples of fall protection equipment, in which disperse yellow 39 was found in two samples with concentrations at 0.081 μg kg−1 and 0.062 μg kg−1, respectively. The developed method can be applied to routine analyses for the determination of 19 allergenic disperse dyes in textiles of fall protection equipment.

The hydrogen evolution reaction is a key half reaction for water electrolysis and is of great significance. Pt-based nanomaterials are promising candidates for HER electrocatalysts. However, the high price of platinum and poor durability impede their practical applications. Herein, a new CoMo-bimetallic hybrid zeolite imidazolate framework is employed to load Pt nanoparticles in a highly dispersed manner as a precursor to synthesize an efficient pH-universal HER electrocatalyst (PtCoMo@NC), which displays overpotentials of 26, 51, and 66 mV at a current density of 10 mA cm−2 in acidic, basic, and neutral media, respectively. The strong synergistic effect of highly dispersed multi-type catalytic species, including cobalt, molybdenum carbide, and platinum (4.7%) promotes the catalytic activity in the HER process. Meanwhile, the aggregation of Pt nanoparticles is greatly restrained by the carbon matrix so that a brilliant long-time durability of 12 hours and a negligible current decrease in the LSV curve after 10 000 CV cycles are achieved.

Inductor-capacitor (LC) passive wireless sensors are implemented by loose coupling between an external read-out coil and an inductor that receives power through this inductive coupling. They allow for continuous real-time detection in harsh or sealed environments where physical access is difficult. Changes in the sensors are wirelessly and remotely detected by the read-out coil. For implanted medical devices or sealed package applications, however, geometrical constraints such as small and noninvasive coils reduce the inductive coupling, turning the remote distance into a fundamental challenge. Here we propose theoretically and demonstrate experimentally that a parity-time (PT) symmetry breaking regime can be utilized to extend the remote distance of the LC passive wireless sensors. In our prototypes, a capacitive humidity sensor is fabricated with graphene oxide (GO) as a sensing material. The variable capacitance in the external read-out coil is cyclic scanned so as to keep the PT-symmetric configuration. Our results show that the read-out distance of the sensors with the PT-symmetric configuration is approximately 4 times as long as that with conventional methods while keeping the same for their sensitivity. The use of PT-symmetry-breaking regimes for the LC passive wireless sensors should enable the interrogation of applications in the implanted or sealed fields.

Inductor-capacitor (LC) passive wireless sensors have been widely used in a variety of applications, ranging from medical diagnosis to industrial and environmental monitoring. In some certain circumstance, the sensors are required to be scaled down to small dimensions, which results in the limited readout distance. Here, a resonant reader is proposed to enhance signal strength and quality factor. The resonant frequency of the reader is changed by controlling varactor. An LC humidity sensor, as an example, is detected both with and without the proposed reader. Experimental results display that the signal strength get greatly enhanced and reflection coefficient S11 is enhanced to -43dB compared with the conventional -0.33 dB, at the same detection distance 1.2cm. Our results may have an impact on wireless sensing, particularly benefiting the emerging micro-machined sensors, and so on.

Mechanical pressures affect the rate and quality of dermal wound healing. It is therefore important to continuously monitor the mechanical pressure on a wound site so as to evaluate neovascularization and cellular proliferation under pressure. Based on an LC (inductor-capacitor) passive wireless principle, this paper presents the design, fabrication, and measurement of LC sensors embedded in a commercial bandage. Pyramidal polydimethylsiloxane elastomers used as the dielectric of the capacitive pressure sensor were fabricated by using a silicon anisotropic etching mold. Simulation and analysis of the LC sensor and wound environment effects were performed. The sensor embedded in the bandage stuck on the skin was measured, showing that its resonant frequency changes according to a linear function of applied pressure in a range of 0–200 mmHg with a sensitivity of −270.8 kHz/mmHg. The demonstrated LC sensor is completely flexible and wearable, which is proper for the future smart bandage.

This letter has experimentally investigated the effect of the external bending on inductor–capacitor ( LC ) wireless humidity sensors fabricated on flexible polyethylene terephthalate (PET) substrates. The LC humidity sensor consisting of interdigitated electrodes for the capacitor was fabricated on the PET substrate by a screen-printing method, and graphene oxide was utilized as the humidity sensing material. The measured sensitivity of the LC humidity sensor is −136.1 kHz/%RH. The behavior of the LC sensor when subjected to circular bending implemented by a customized bending setup has been tested through changes in resonant frequency. The ratio of the projected area under bending constraints to the initial area of the sensor is proposed to characterize the curvature of the sensor. It shows that the bending causes the ratio to decrease, which results in the resonant frequency ascent with the fitting slope being approximately 10.8 MHz/ratio for the ratio from 1 to 0.6. The reduction in capacitance and inductance of the LC sensor is subjected to circular bending accounts for the resonant frequency ascent. The results presented here would be a valuable reference for the future applications of the LC sensor on the flexible substrates. [2018-0066]

This paper presents a new method for real-time measuring the temperature-dependent relative dielectric constant and the thermal expansion coefficient of the silicone oil by using a low-cost microelectromechanical systems (MEMS) structure. The relative dielectric constant of the silicone oil can be obtained by measuring the capacitance of an MEMS temperature sensing structure, and the silicone oil is used as the temperature sensing material of the capacitive structure. A processing circuit on a printed circuit board is designed to complete the measurement. A theoretical model is constructed to describe the behavior of the relative dielectric constant and the thermal expansion coefficient over a certain range of temperatures. Preliminary experimental results show that the variation of the relative dielectric constant and the thermal expansion coefficient versus temperature could be detected real timely and simply based on this method.

Inductorcapacitor (LC) sensors have advantages in situations where wired connections are impossible in harsh environments. Due to the wireless mutual coupling, the LC sensor can resist most external influence brought by the ambient objects, even when they are in the propagation path. However, the metals can shield electromagnetic waves, which affects the signal readout. A metal plane is added at the back of the LC sensor to study the interrogating change. A simulation and an equivalent circuit are demonstrated to give a theoretical analysis. Then, experiments are conducted to conclude that the metal plane will shift the resonant frequency of the LC sensor to be greater and weaken the Q factor of the LC sensor.

The rate and quality of dermal wound healing can be greatly affected by mechanical pressure and moisture content, which need to be continuously monitored for wound management. Here we present a flexible passive wireless pressure and moisture sensor based on a LC-type dual resonant circuit. The sensor consists of a moisture sensitive interdigital capacitor, two identical pressure sensitive plate capacitors and two equivalent inductors. Pyramidal polydimethylsiloxane elastomer is utilized as the dielectric layer of the pressure sensitive capacitors, and graphene oxide is used as the moisture sensing material. Experimental results demonstrate that the fabricated sensor has humidity sensitivity of -61 kHz/%RH from 20 %RH to 90 %RH and pressure sensitivity of -388.6 kHz/mmHg from 0 mmHg to 100 mmHg.

The influence of low-mode-driven asymmetry on yield degradation in shaped-pulse indirect-drive implosions has been investigated at the 100 kJ laser facility. In this work, P2- and P4-driven asymmetries were tuned by varying hohlraum gas-fill density and capsule diameter. The measured neutron yield varied from 2.1 × 109 to 7.6 × 109 and the yield measured by a 1D simulation (YOC1D) was increased from 3% to 16%. Meanwhile, considering the temporal P2- and P4-driven asymmetries, the yields measured by 2D simulations (YOC2D) were from 26% to 81% (the YOC2D of the majority of the shots was higher than 50%). Furthermore, both the ion temperature and neutron bang-time showed good agreement between the measurements and the 2D simulations. The simulations demonstrated that the temporal P2- and P4-driven asymmetries can decrease the efficiency of PdV work and increase the energy loss due to electron thermal conduction. In addition, the internal energy of the deuterium (DD) fuel clearly decreased and the neutron yield was degraded by low-mode asymmetry. In a future work, we will enlarge the cylindrical hohlraum diameter or use an I-hohlraum to improve the low-mode-driven symmetry, along with measurement of the hot-spot shape.

In this study on the curing dynamics of phenol-formaldehyde novolac resins (PFNR) and hexamethylene tetramine (HMTA), two typical commercial PFNR were selected as examples and the curing reactions of the resins with HMTA were studied by differential scanning calorimetry (DSC). Based on the data calculated by the Kissinger equation and the Crane equation, a thermocuring dynamic model was established, from which the process conditions, activation energy, reaction kinetics equation and a first-order reaction of the curing reactions were derived.

In this paper, an overview of experimental research and production of 40.5mm DNV 485FDU heavy wall thickness pipeline steel for deep water trunkline project was introduced and analyzed systematically. Alloy design of the steel was introduced. Continuous cooling phase transformation behavior of the steel under deforming condition was investigated. The microstructure of the steel at different cooling rates was observed by the microscope. An optimized cooling process (OCP) after finish rolling was developed in Shouqin Steel Co., Ltd. (SQS). The optimized cooling process guaranteed the steady control of the final bainitic microstructure with optimum polygonal ferrite (PF) for heavy gauge DNV 485FDU plates. The plates produced by this process achieved good tensile strength and excellent lower temperature toughness. The pipes were produced via the JCOE pipe production process and had favorable forming properties and good weldability. Plate mechanical properties successfully met the required final pipe mechanical properties due to the ideal microstructure from the alloy/OCP design.

We discuss the formation of a Kelvin–Helmholtz instability (KHI) produced by a laser-driven thin separate plastic (CH) foil plasma. The experimental design consists of magnetized plasma driven by intense laser irradiation and a small cylindrical permanent magnet. By comparing situations with and without an external magnetic field, we found that the KHI showed different rolling features which could be effectively suppressed by an external magnetic field. A quantitative analysis shows the consistency between the experiments and theory.

Photocatalysis induced by sunlight is one of the most promising approaches to environmental protection, solar energy conversion, and sustainable production of fuels. The computational modeling of photocatalysis is a rapidly expanding field that requires to adapt and to further develop the available theoretical tools. The coupled transfer of protons and electrons is an important reaction during photocatalysis. In this work, we present the first step of our methodology development in which we apply the existing kinetic theory of such coupled transfer to a model system, namely, methanol photodissociation on the rutile TiO2(110) surface, with the help of high-level first-principles calculations. Moreover, we adapt the Stuchebrukhov-Hammes-Schiffer kinetic theory, where we use the Georgievskii-Stuchebrukhova vibronic coupling to calculate the rate constant of the proton coupled electron transfer reaction for a particular pathway. In particular, we propose a modified expression to calculate the rate constant, which enforces the near-resonance condition for the vibrational wave function during proton tunneling.

We have experimentally investigated the gas cell pressure effect of high-order harmonic generation in argon and neon. The selective enhancement of high-order harmonic intensity in the energy range of 60–70 eV in the spectrum has been obtained in argon. The experimental results are simulated theoretically, and the main characterizations of the experimental observations are reproduced. By studying the ionization term effect in the simulation, we conclude that it is the plasma effect improves the phase-matching condition for this specific spectrum range and finally brings the enhancement.

This paper presents an integrated wireless passive sensor for remotely monitoring both temperature and relative humidity. The sensor consists of a coil and a capacitor to form an inductor–capacitor ( $LC$ ) resonant circuit, which oscillates electrically at its resonant frequency. The inductor was a single-layer planar spiral copper inductor and the capacitor was fabricated by the silicon-on-glass process, which utilizes graphene oxide films as the sensing material. The change of the capacitance due to environmental humidity variation shifts the resonant frequency, while environmental temperature affects the resistance and capacitance of the $LC$ circuit and changes the resonant frequency and quality factor. By monitoring the real portion magnitude maximum of the impedance and the resonant frequency for the sensor, it is possible to get the capacitance and resistance from which the temperature and humidity can be extracted. The results presented here show that the sensitivity of the passive wireless sensor is about −17.80 kHz/%RH and $7.32~\Omega $ /%RH at 25 °C from 55%RH to 95%RH, and it is about −7.69 kHz/°C and $6.27~\Omega $ /°C at 65%RH from 10 °C to 40 °C. [2014-0311]

This paper presents a novel capacitive sensor for real-time monitoring of temperature in the silicone oil fan clutch. The structure of the temperature sensor is designed and fabricated by the Silicon-On-Glass (SOG) process based on the bonding technology. The silicone oil is designed as the temperature sensing materials in the capacitive sensor. The capacitance of the embedded sensor is changing with respect to temperature of the silicone oil fan clutch. Experimental results show that the sensor provides a sensitivity of 27.3fF/°C in the -30 to 40°C range, 58.2fF/°C in the 50 to 110°C rang. It is also demonstrated that the temperature sensitive capacitor can be integrated with a copper inductance antenna and tests as a passive wireless temperature sensor. The resonant frequency of the inductor-capacitor (LC) resonator changes with respect to the changing capacitance. Then temperature changes can be remotely determined towards a frequency spectrum study. Experimental results show that the LC type passive wireless sensor provides a sensitivity of 6.35kHz/°C in the -30 to 110°C range.

The parallel capacitive temperature micro-sensor is designed and fabricated based on the metal multi-user MEMS processes. The interdigitated capacitors parallelly connected with the plane capacitor are used as the temperature sensing structures. Thermal expansion of the top layer cause the out-of-plane deformation, and introduce horizontal and vertical displacements of the structure, which leads to the capacitance variation. Top metal layer is the cascaded bent beam with interdigitated end, which is used as the interdigitated capacitors. Polysilicon layer paired with metal layer to form the plane capacitor. Experimental results show that the sensor provides an average sensitivity of 32.45 fF/°C in the 0–100°C range. It is also demonstrated that the temperature sensor can be integrated with an inductor to form an LC passive wireless sensor, which provides a sensitivity of 46.61 kHz/°C in the whole temperature range.

This paper focused on a new direction of study on leakage current called substrate charge injection. The substrate leakage current of capacitive RF micro-electro-mechanical-system (MEMS) switches was measured, and the conduction mechanism was estimated. The study of the leakage current conduction mechanisms of the substrate dielectric film shows that leakage is mainly induced by hopping conduction at low electric fields, whereas both Schottky emission and hopping conduction may contribute to the leakage current at high fields. The quantitative relationship between the substrate leakage current and the dielectric layer leakage current was also determined for the first time. In the case of low drive voltage (0–30 V), the substrate leakage current significantly contributes to the total leakage current. Results show that the charging properties of the substrate should not be neglected at low drive voltage because such properties could significantly affect the functionality and reliability of RF MEMS switches.

An advanced experimental rig for heat pump water heaters was established. The performances of both a phase change heat-storage-type heat pump water heater (Type A) and a conventional heat pump water heater (Type B) were tested and compared according to GB/T 23137-2008 using the experimental rig. The results showed that the existence of phase transition temperature platform enabled the phase change heat-storage-type heat pump heater run longer and more steadily. When the same hot water heat capacity obtained, the volume of the accumulator in the Type A water heater accounted for about 56.9% of that of the water tank in the Type B water heater, which could save the overall size of water heater significantly and therefore promote the wide application of energy-saving heat pump water heaters.

The configuration sizes of multi-layer rectangle micro-channel heat sink are optimized, which has been widely used to cool electronic chip for its high heat transfer coefficient and compact structure. Taking the thermal resistance and the pressure drop as goal functions, a binary-objective optimization model was proposed for the multi-layer rectangle micro-channel heat sink based on Sequential Quadratic Programming (SQP) method. The number of optimized micro-channel in width n1 and that in height n2 are 24 and 3, the width of optimized micro-channel Wc and fin Wf are 360 and 55μm, the height of optimized micro-channel Hc is 1000μm, and the corresponding total thermal resistance of the whole micro-channel heat sink is 1.5429 °C/W. The corresponding pressure drop is about 2.3454 Pa. When the velocity of liquid is larger than 0.3 m/s, the effect of change of velocity of liquid on the thermal resistance and pressure drop can be neglected.

The single-phase flow and heat transfer for multi-layer rectangle micro-channel heat sink are numerically simulated. During the simulation, Finite Volume Method (FVM) was used to solve Computational Fluid Dynamics (CFD) problem. First order upwind scheme was used to discrete control equations, and semi-implicit method for pressure-linked equations was used to solve discretization equations. The maximum temperature difference is 76.2362 °C, and the total thermal resistance is 0.4765 °C/W, which agrees well with the result of analysis result 0.5145 °C/W. The corresponding pressure drop is about 54.1360 N/m2.

Fabrication of a novel in-plane field emission diode structure is presented. Sub-micro metal tips were obtained using a two-step lithography method. The Minimum width of the metal tips was less than 100nm, and the minimum spacing of 145.7nm was obtained. The I-V characters in atmospheric environment before and after the silicon etching were measured.

The purpose of this paper is to optimize the structural sizes of multi-layer rectangle micro-channel heat sink, which has been widely used to cool electronic chip for its high heat transfer coefficient and compact structure. Taking the thermal resistance and the pressure drop as goal functions, a binary-objective optimization model was proposed for the multi-layer rectangle micro-channel heat sink based on Sequential Quadratic Programming (SQP) method. The number of optimized micro-channel in width n1 and that in height n2 are 21 and 7, the width of optimized micro-channel Wc and fin Wf are 340 and 130μm, the height of optimized micro-channel Hc is 415μm, and the corresponding total thermal resistance of the whole micro-channel heat sink is 1.3354 °C/W. The corresponding pressure drop is about 1.3377 Pa. When the velocity of liquid is larger than 0.3 m/s, the effect of change of velocity of liquid on the thermal resistance and pressure drop can be neglected.

A capacitance-voltage (C- V) model is developed for RF microelectromechanical systems (MEMS) switches at upstate and downstate. The transient capacitance response of the RF MEMS switches at different switch states was measured for different humidity levels. By using the C -V model as well as the voltage shift dependent of trapped charges, the transient trapped charges at different switch states and humidity levels are obtained. Charging models at different switch states are explored in detail. It is shown that the injected charges increase linearly with humidity levels and the internal polarization increases with increasing humidity at downstate. The speed of charge injection at 80% relative humidity (RH) is about ten times faster than that at 20% RH. A measurement of pull-in voltage shifts by C- V sweep cycles at 20% and 80 % RH gives a reasonable evidence. The present model is useful to understand the pull-in voltage shift of the RF MEMS switch.

Effect of temperature to associated thermal physical characteristics is analyzed by establishing laser cutting model for stainless steel. Experiment shows the position of focus has an effect on cutting quality. Perfect positions of focus for different thickness are advanced. On this basis, applying the law of conservation of energy, where the total heat absorbed is equal to the sum of absorbed by melting and lost by conductive, heat onduction equation is set up. The function relation among cutting speed, thickness of plate and power is defined, which is verified to get perfect cutting quality in TRUMPF L3030. The formulations provide theoretical and practical support for actual laser cutting of stainless steel.

The character of microstructure in the segregation of 82B wire with two different stelmor control cooling procedures and kinetics of eutectoid transformation of segregation through thermal simulation in the range of 400-600°C were researched. The longitudinal section segregation microstructure and composition were analyzed by OM、SEM、WDS. The thermal simulation results show that the length of martensite segregation bands is decreased as holding time increases above a certain temperature, and martensite band in the core of wire where the content of Mn and Cr elements is higher than matrix because of segregation. Furthermore, Stelmor control cooling experiments in the high speed wire mill confirms that there is a critical temperature to 82B wire above which the eutectoid transformation in the segregation is possible, and enough time above the critical temperature in the Stelmor control cooling lids is the key to optimizing procedure.

This paper presents the design, analysis and measurement of a high linearity capacitive temperature sensor fabricated by MetalMUMPs process. The capacitive temperature sensor consists of two kinds of temperature sensitive capacitors, which are vertical movement temperature sensitive capacitor and lateral movement temperature sensitive capacitors. By using lateral capacitors to compensate the nonlinearity of vertical capacitor, high linearity and proper sensitivity characterization is achieved. The measured nonlinearity of the capacitive temperature sensor is less than 1%, and its sensitivity is 19.4 fF/K.

In order to study the performance of gas-spray water quenching, the gas-spray water quenching test to 9SiCr alloy steel was conducted. After quenching , the hardness and metallographic structures were investigated. The results show that the hardness of the specimen was greatly improved, and the inner hardness was a little higher than the outer. Besides, the uniform martensite was obtained after quenching.

The configuration sizes of multi-layer microchannel heat sink is optimized in order to enhance the performance of the high flux chip, which is 556W/cm2. Taking the thermal resistance and the pressure drop as goal functions, a double-objective optimization model was proposed based on the thermal resistance network model. The opimized microchannel heat sink is numerically simulated by computational fluid dynamics (CFD) software. The number of microchannel in width n1 and that in height n2 are 24 and 2, the width of optimized optimized microchannel and fin are 196 and 50 μm, respectively, and the corresponding total thermal resistance of the whole microchannel heat sink is 0.4025 °C/W. The highest temperature is less than 98°C, which can satisfy the requirement of chip to temperature. The maximum temperature difference is 77.8673°C, and the transferred power of heat flux is 200W, so the total thermal resistance is 0.3893 °C/W, which agrees well with the analysis result of thermal resistance network model.

Alloy steel 9SiCr is quenched by a certain proportion of mixture gas of nitrogen and spray water at atmosphere, and the continual cooling curve during quenching is determined, the rigidity of quenched workpiece is measured and the metallographic map is captured. The results show that it can improve the cooling effect of quenching medium on the one hand; on the other hand, it can decrease the deformation and residual stress of workpieces. The results show that the rigidity of quenched workpiece is about 62 (HRC), which is corresponding with the rigidity after oil quenching. Martensite phase transformation occurs at the end of quenching that can be seen from the metallographic map.

In this paper, a LC tank circuit has been designed, fabricated and tested, to study the temperature dependence of the quality factor in the LC-type passive wireless temperature sensors. The performance of the wireless signal transmission is studied by a group of inductances and by studying the impedance characterization of the LC tank. A theoretical model of temperature dependence of quality factor is established, and is found to be in good agreement with the experiment results. The quality factor Q as a function of temperature, expressed in Q-factor shift per temperature difference, is 0.0246/ °C, which compares well to the theoretically determined slope of 0.0275/ C. Up to 2.5% change in quality factor per C change of temperature is demonstrated. Both the resonance frequency and the quality factor Q of the LC sensor are strongly dependent on temperature.

A new method is described for measuring the temperature-dependent dielectric constant of the PDMS fluids by using a low cost MEMS sensor. The dielectric constant of the PDMS fluids is obtained by measuring the capacitance of a MEMS temperature sensor, which uses PDMS fluids as its sensitive material. Despite properties of the PDMS fluids in different temperature plays an important role in practical applications, few designs for measuring the relative static dielectric constant and the thermal expansion coefficient over different temperature have been developed. We construct a theoretical model which describes the behavior of the relative static dielectric constant and the thermal expansion coefficient over a certain range of temperatures. Preliminary experimental results show that the variation of the relative static dielectric constant and the thermal expansion coefficient versus temperature could be detected simply based on this method.

In this work, we mainly summarize the influence of the ion bombardment cathode (target) and relative factors of magnetron sputtering yield in production thin film. Magnetron sputter deposition permits a much wider selection of film materials, produces films with higher purity and better controlled composition, provides films with greater adhesive strength and homogeneity, and permits better control of deposit thickness. Unlike most other work described about sputtering yield, sputtering for thin-film production is performed using the plasma rather than a focused ion beam. When an ion with the energy hits a surface of the target, a small fraction of the energy and momentum of the incoming ion will, through lattice collisions, be reversed and may cause ejection of surface atoms (sputtering). The average number of the atoms ejected from the cathode surface per incident ion is called the sputtering yield. The sputtering yield varies with the target material, the kind of impinging ion, and the energy of that ion. At a given ion energy, The sputtering yield increases with increasing angle of incidence up to a maximum at an angle between 55 ° and 85 ° with respect to the surface normal [1, 3].

Unconfined compressive strength of various mixing proportions and ages of nanometer silicon and cement-stabilized soils（NCSS） are tested ,and the rules of compressive strength are got. Hydration products and microstructures of NCSS are discussed by means of XRD and SEM technology, and microstructural mechanisms of NCSS are analyzed. Results show that nanometer silicon powder added to cement-stabilized soil(CSS) can sharply improve the compressive strength of CSS. More Calcium silicate hydrates(C-S-H) and other hydration products can be produced in the process of secondary reaction of cement and water added nanometer silicon powder. X ray diffraction tests indicate the kinds and quantities of C-S-H increase with nanometer silicon contents. Strengths of NCSS are bettered by increasing jointed strength changed from edge-edge, edge-face connectios to cementation connections affected by increasing hydration products. Large pores of NCSS can be greatly decreased by adding nanometer silicon powder, and hydration products filling in the pores make NCSS more dense materials.

Cement-stabilized soil has been widely used to ground treatment, tracing of foundation pit, water resistance. Additives in cemented soil play an important role in improving its basic properties of cemented soil. In this paper, a new kind of additive, Nanometer Silicon Oxide (SiO2-x), was incorporated into cemented soil. Undrained triaxial compression tests were performed to discuss the reinforced effect of the nanometer silicon on the strength property of the cemented soil. Four main factors that influence the compressive strength of the nanometer silicon cemented soil (NCS) are considered: cement content, nanometer material content, confining pressure, and water\cement ratio. Based on orthogonal tests, the paper analyzed quantitatively the main influence factors of the compression strength of NCS and presented the optimum mix combination. A linear regression model for the compression strength were proposed. Finally, some conclusions have been achieved.

Different temperature rises during finishing rolling of T8 cord steel were obtained through normal procedure (process 1) and controlled cooling procedure (process 2), and its effects on the microstructure and the mechanical properties were studied. The microstructure of T8 cord steel obtained by process 1 consisted of clusters of coarser and inhomogeneity sorbite colonies, and that obtained by process 2 consisted of equiaxed and finer sorbite colonies, with the similar interlamellar spaces of sorbite cementite in the two microstructures. The results of tensile tests showed that the tensile strength of T8 cord steel obtained by process 2 was higher than that obtained by process1 by 20MPa, with higher reduction of area and tensile elongation. In addition, the tensile fracture of T8 cord steel obtained by process 1 consisted of a lot of lotus cleavage plane, while that of T8 cord steel obtained by process 2 mainly consisted of finer dimples. That indicated that the smaller temperature rise of process 2 during finishing rolling can improve the mechanical properties of T8 cord steel.

Though gas quenching has several advantages, such as minimal environmental impact, little deformation, low energy cost, clean products, and ability to control the cooling locally and temporally for best product properties, its cooling performance is less than that of oil and water. If gas is mixed with spray water, the mixture will has favorable cooling performance. The cooling performance of eject quenching by mixture of Nitrogen-spray water is studied experimentally. Alloy steel 9SiCr is specimen, and it is quenched by a certain proportion of mixture gas of Nitrogen and spray water under normal pressure and high velocity, and the continual cooling curve is determined. The experimental results show that it can improve the cooling effect of quenching medium on the one hand; on the other hand, it can decrease the deformation and residual stress of specimen. The results also show that cooling performance of the mixture and cooling velocity can be enhanced by increasing gas pressure when the mixture ratio is fixed, and it takes short time to cool to room temperature. The cooling performance of the mixture and cooling velocity can be enhanced by increasing the mixture ratio under same pressure, and it also takes short time to cool to the room temperature. The continual cooling curve is determined, which gives the information of cooling performance of eject quenching by mixture of Nitrogen-spray water under Normal pressure changed with the pressure and the mixture ratio of Nitrogen and spray water.

In order to analyses the effect of structure of collection loop on two-phase flow field in quenching furnace, the complex flow field in furnace for mixture of Nitrogen and spray water ejecting quenching under normal pressure and high velocity is numerically simulated with Mixture model of two-phase flow by CFD software FLUENT. Different inlet velocity, different volume percent of spray water, different velocity differences between Nitrogen and spray water, and different angle and dimension of collection loop affected on outlet velocity are analyzed. The research results show that the flow field is really complex, and around inner and outside canister and collection loop back flow exists. The angle of collection loop has less effect on outlet velocity, and the inner diameter of collection loop has more effect on outlet velocity. The simulation results show that the furnace can accelerate the flow of quenching media, which can cool specimen quickly.

An integrated humidity sensor capable of passive wireless sensing through inductive coupling is presented. The sensor chip consists of two stacked counter-rotating planar aluminium inductors (0.5 μm thick, 100 μm in width, 50 μm space and 6 mm outer diameter) separated by a maskless polyimide film. The two inductors are inductively and capacitively coupled together to form a resonant tank, whose resonant frequency changes with humidity. This topology eliminates the need of a connection bridge or via as used in the usual inductor–capacitor humidity sensors and offers higher sensitivity due to the inner humidity-sensitive parallel-plate capacitor in contrast with the single-layer self-resonant inductor. Three sensor devices with different inductor turns were fabricated and characterised. Measurements show a sensitivity of 45 kHz/%RH with a centre frequency of 50.5 MHz for sensor A (8 turns), 15.8 kHz/%RH, 22 MHz for sensor B (10 turns) and 65 kHz/%RH, 74 MHz for sensor C (4 turns).

In this paper, some virtuallab experiments have been done, in which the we get extraordinary transmission phenomenon by adding dielectric coating in the subwavelength periodic metallic slits. It is proved that dielectric coatings on the metal films can excite a surface wave which is transmitted in the metal slits by dielectric waveguides, and the symmetric wrapped dielectric cladding around the metal gains almost 10 times as great transmission as two surfaces cladding does. The paper explores a preliminary physics mechanism of this extraordinary transmission, which gets some valuable results in the application fields.