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The thermal stress damage process of 1080 nm laser ablation of single crystal germanium was recorded in real time using a high-speed CCD. A three-dimensional finite element numerical model based on Fourier's heat conduction equation, Hooke's law and Alexander Hasson equation was developed to analyze the thermal stress damage mechanism involved. The damage morphology of the ablated samples was observed using an optical microscope. The results show that the cooling process has an important influence on the fracture in the laser irradiated region of single crystal germanium. The fracture is the result of a combination of thermal stress and local yield strength reduction.

A brief description of EMC (electromagnetic compatibility) design in FSECU (Flap and Slat Electronic Control Unit) is proposed. FSECU (Flap and Slat Electronic Control Unit) is the core component of High Lift System. The FSECU’s EMC design for case, I/O interface circuit, ground and PWB is described in detail. In parallel, the analysis for the electromagnetic environment difference of HLS is proposed. The EMC design methodology of FSECU is introduced, which includes the chassis, interface circuit, grounding and PWB. The requirements of controlling the electromagnetic leakage and interference are satisfied by using this way. Several tests of DO-160G are to be performed and the EMC requirements need to be met.

The synchronization of the spin Hall nano-oscillator (SHNO) device driven by the pure spin current has been investigated with micromagnetic simulations. It was found that the power spectra of nanowire-based SHNO devices can be synchronized by varying the current flowing in the heavy metal (HM) layer. The synchronized signals have relatively high power and narrow linewidth, favoring the potential applications. We also found that the synchronized spectra are strongly dependent on both the number and length of nanowires. Moreover, a periodic modulation of power spectra can be obtained by introducing interfacial Dzyaloshinskii–Moriya interaction (iDMI). Our findings could enrich the current understanding of spin dynamics driven by the pure spin current. Further, it could help to design novel spintronic devices.

Once the metalenses are fabricated, the functions of most metalenses are invariable. The tunability and reconfigurability are useful and cost-saving for metalenses in realistic applications. We demonstrate this tunability here via a novel hybrid metalens with the strategic placement of an ultra-thin VO2 layer. The hybrid metalens is capable of dynamically modulating the focusing intensity of transmitted light at a wavelength of 1550 nm, and demonstrate a 42.28% focusing efficiency of the incident light and 70.01% modulation efficiency. The hybrid metalens’ optothermal simulations show an optothermal conversion process of dynamic focusing, and a maximum laser density of 1.76×103 W/cm2 can be handled at an ambient temperature lower than 330 K. The hybrid metalens proposed in this work, a light-dose sensitive tunable smart metalens that can protect other instruments/systems or materials from being damaged, has its specific applications such as in anti-satellite blinding, bio-imaging, etc.

In this paper, a linear distribution model, a double exponential distribution model and a hyperbolic number distribution model are developed, and the effect of dust particle size distribution on its attenuation coefficient is considered. On this basis, the transmission characteristics of electromagnetic waves in dusty plasma under different electron density distribution models are investigated. The attenuation coefficients of electromagnetic waves are derived in detail using analytical methods, and the effects of electromagnetic wave frequency, particle collision frequency and dust particle density on the transmission characteristics of electromagnetic waves are discussed. The results show that the choice of terahertz wave as the carrier wave and the appropriate change of particle collision frequency can improve the attenuation of electromagnetic waves. In summary, the relevant research can provide some theoretical references for propagation science.

With the rapid development of science and technology in the world today, the development of the Internet is even more remarkable. Especially under the stimulation of continuous breakthroughs in the computer field, the network economy, as an important part of the knowledge economy, is growing rapidly and has become a new driving force for world economic growth. In order to meet the needs of the development of the network economy, traditional enterprises should implement e-commerce to be able to quickly respond to customer needs, improve business processes with customer relationships, provide personalized services, shorten sales cycles and sales costs, increase revenue, and develop markets, to enhance the competitiveness of enterprises.

Mining subsidence, a major geological disaster caused by underground mining, will seriously damage the land. In this paper, the author predicts the surface subsidence in mining subsidence area of certain mineral deposits and strata condition by applying the Probability Density Function Method, and designs two evaluation schemes for calculation of the overlying rock formation stability. Study results provide a reliable basis for the disastrous governance of mining subsidence in mining areas.

Preparation of activated carbon from biomass ash residue can effectively treat solid waste and improve the economics of the biomass power generation industry. However, the low thermal conductivity of activated carbon (AC) cannot make it widely used. A strategy was reported herein modify the activated carbon by AlN increase its thermal conductivity. Effects of reaction temperature, nitriding time, and nitrogen flow rate on the formation AlN and summarized the optimal process of AlN modified activated carbon. The result showed that the optimal preparation process is to inject nitrogen at a rate of 300 ml/min, under the condition of 1550°C, nitriding reaction for 50 min. The thermal conductivity of AlN-modified activated carbon prepared by this process is twice that of unmodified activated carbon.

In this article, we chose carbon nanofibers (CNFs) with high aspect ratio and excellent mechanical strength to investigate the evolution of the assemble behavior belong to the nanofillers and its effect on mechnaical properties of CNFs enhanced polymethyl methacrylate (PMMA) base denture resins. Test specimens were manufactured by mixing 0.5%, 1% and 3% content of CNFs with PMMA powder and the flexural properties of the specimens were tested by three-points testing. Comparing with the low flexural strength of pure PMMA base denture resins, Statistical evaluation results revealed that CNFs fillers highly improved the flexural strength of the composite resins to 66.44 ± 1.40 MPa, 68.75 ± 6.82 MPa and 89.26 ± 1.97 MPa at content reached 0.5%, 1% and 3%, respectively. Flexural modulus of neat PMMA was 2.79 ± 0.48 GPa, and the flexural modulus of the sample contains 0.5%, 1% and 3% reached 6.42 ± 0.75 GPa, 5.95 ± 0.29 GPa and 6.27 ± 0.14 GPa, respectively. Scanning electron microscopy revealed the aggregation of CNFs fillers, which is considered a stereoscopic framework that played the role of a special enhancing reinforcement under low filler content, and this strategy is considered to be expanded and developed to a common strategy that guiding our design in composite denture resins.

A yoke-based permanent magnet, which has been employed in many watt balances at national metrology institutes, is supposed to generate strong and uniform magnetic field in an air gap in the radial direction. However, in reality the fringe effect due to the finite height of the air gap will introduce an undesired vertical magnetic component to the air gap, which should either be measured or modeled towards some optimizations of the watt balance. A recent publication, i.e., {\it Metrologia} 52(4) 445 [1], presented a full field mapping method, which in theory will supply useful information for profile characterization and misalignment analysis. This article is an additional material of [1], which develops a different analytical algorithm to represent the 3D magnetic field of a watt balance magnet based on only one measurement for the radial magnetic flux density along the vertical direction, $B_r(z)$. The new algorithm is based on the electromagnetic nature of the magnet, which has a much better accuracy., Comment: 19 pages, 10 figures, submitted to Metrologia

The joule balance experiment has been carried out at the National Institute of Metrology, China (NIM) since 2007. By the end of 2013 the first generation of the joule balance (NIM-1) achieved a measurement uncertainty of 7.2 × 10−6 (k = 1). To reduce the measurement uncertainty further, the next generation of the joule balance apparatus (NIM-2) system is under construction. A new coil system using ferromagnetic material is being adopted in NIM-2 to reduce self-heating in the coils. However, the effects on the measurement of the mutual inductance from the nonlinearity and hysteresis of the ferromagnetic material will bring a considerable measurement uncertainty. Inspired by the watt balance, the measurement of the mutual inductance is replaced by an equivalent measurement of the magnetic flux linkage difference. The nonlinearity and hysteresis will not be a problem in the measurement of the magnetic flux linkage difference. This technique comes from the watt balance method. It is called the generalized joule balance method, which is actually a modification of the watt balance method. However, it still represents a valid change that can reduce the difficulty of dynamic measurement experienced using the watt balance. Permanent magnets can also be adopted in the generalized joule balance. To check the feasibility of the generalized joule balance method, some preliminary experiments have been performed on NIM-1. A yokeless permanent magnet system has been designed and used to replace the exciting coils in NIM-1. In this paper, the structure of the yokeless permanent magnet system is introduced. Furthermore, a determination of the Planck constant with the permanent magnet system is presented. The value of the Planck constant h we obtained is 6.626 069(17) × 10−34 J s with a relative standard uncertainty of 2.6 × 10−6.

Geohazards caused significant damages to people and economical properties. The prevention and mitigation of geohazards in China is facing great challenges. To solve the problem, establishing a national geohazard information system is important in accessing the distribution of geohazards, optimizing the efforts of prevention and mitigation, and improving the public awareness and risk reduction capabilities. After two decades’ of development, China national geohazard information system have upgraded from client-server (C/S) to browser-server (BS) architecture, and now to the micro-service based architecture, more than 320 thousands of geohazards which were mainly collected through field surveys and the routine field inspections have been saved in the database; through the information system, data acquisition and integration, classified storage, efficient data processing, real-time statistics and data services have been achieved and standardized by numerous technical specifications. In this paper, the current status of China national geohazard information system, including the development progress, database architecture, system functionality and data applications are introduced, and expected to provide references of establishing an efficient and comprehensive geohazard information system to improve the geohazard risk reduction capabilities for the countries or regions suffering from geohazards.

The automatic driving of trains is an inevitable trend of the modern development of railway transportation, and it is also a necessary requirement for energy conservation and emission reduction. A train automatic driving speed planning scheme with only one operation state transition point in the simplified slope section is proposed based on slope simplification principle and speed limit regulation on an interval line, which reduces the control complexity and energy consumption for automatic driving. An improved fitness function of genetic algorithm (GA) is explored to solve an operation state transition point position of the train, then train energy-saving operation strategy is presented. Practical energy costing experiment for freight train (HXD3) with 2,800 tons for a 33.7km line on Bin-Zhou railway line is obtained and compared with the proposed algorithm. Results show that energy consumption is saved by 15.2% for the speed strategy from the proposed method. So operation strategy is simplified greatly because of only one state transition point in a simplified interval which is more suitable for automatic driving. On the other hand, one point operation strategy is also more energy efficient than manual manipulation. Therefore, the proposed method provides a simple and efficient control strategy for train automatic driving.

Waterfront caisson wall is commonly seen port structure that could be heavily damaged by liquefaction. Although the mitigation measures were mostly proved efficient in theory, yet insufficient, particularly in providing an easily implemented remedial plan with design parameters for routine practices of liquefaction risk reduction. In this study, using the damaged caisson wall structure recorded from case history as the unimproved benchmark, the remediation effectiveness of a joint method - the stone column and deep mixing method for liquefaction risk reduction is examined based on the deformation comparison between the damaged and hypothetically improved seismic performance of the wall-soil system. Highlights on the establishment of liquefaction risk reduction process for caisson walls are generated as recommendations for practices.

Improving the capability of geohazard data online analysis and evaluation for geohazard prevention and mitigation is the major developing trend of geohazard information service and relevant research. Making use of the information technologies to solve the technical challenges and difficulties encountered in geohazard big data processing and analysis is important to effectively improve the capacity of geohazard information service. By using the micro-service, one of the advanced information technology, this study proposed an technical solution for the construction of geohazard data online analysis and processing service, which was designed and constructed based on the working mechanism and procedure of the analysis. As an example, the geohazard online susceptibility analysis service was designed and developed. In the proposed technical solution, the online susceptibility analysis service was splitted into multiple operational-independent and also interconnected micro-services for the completion of the analytical process. The developments of each individual micro-service provide support for further revision, upgrade and expansion of the data analysis ultimization or model optimization. The propose of the technical solution further deepens the integration of geohazard research and information technology to improve the level and practical efficiency of geohazard information service leading by the advancement of information technology.

The joule balance is one of the mass traceability devices in the revised International System of Units, and its smooth operation relies on a compensation coil to reduce the effect of the external magnetic field. In this paper, the interaction between the magnetized coil-suspension system and the compensation coil, which has never been noticed, is theoretical analyzed and experimental verified. First, an additional induced voltage can be detected in the compensation coil when it moves relative to the magnetized coil-suspension system, which will lead to a measurement deviation of several parts in E6 in the moving phase. Second, if the excitation current also flows through the compensation coil in the weighing phase, then an additional magnetization force which can not be canceled out by the mass-on and mass-off measurements will be applied on the coil-suspension system. Theoretical analysis indicates that the deviations introduced in the two phases are nearly equivalent, so that the final mass measurement result will not be affected at least on the magnitude of E-9. However, this conclusion can only be verified at E-8 level due to the current measurement limitations of the joule balance.

The completeness of pipelines is tremendous influenced by landslide in unfavorable geological conditions. The quantifying appraisal techniques is a valid means for risk management of pipelines affected by geological disasters. By using the finite element method to simulate going steadily downhill, mechanics characteristic of pipeline and pipe/soil interaction with changes in physical dimension consisted of the landslide area (LA), landslide thickness (LT), pipeline length in landslide (PLL), calibre (CA) and wall thickness (WT) of pipeline, the fragility appraisal system of pipeline affected by landslide can be constructed. The regular pattern of stress and strain variation of pipeline affected by landslide can be acquired with number analysis and computeration. The results show that the physical dimension of landslide and the PLL have strong effect on pipeline fragility, and the effect increases with increasing of the above indicators; the WT has a smaller role of pipeline fragility and the effect can be ignored. In the end, the weighting factors and marks of every fragility appraisal indicator can be given on the basis of the above conclusion.

The effect of stress level and loading path on rehological behavior of alternating distribution of soft and hard rock layers are investigated with triaxial creep and uniaxial experiments. The results have shown that Different stress states and loading paths have some influence on the rheological behavior of the rock mass. The creep displacement of the rock mass is increased and the lower the confining pressure is, the more obvious the rheological property of the rock mass is, which indicates that the confining pressure has a certain inhibitory effect on the rheology of rock mass.

In this paper, three-dimensional unsteady Navier-Stokes equations coupled with six-degree-of-freedom equations are solved numerically to simulate the process of multi-body separation in the condition of high speed and high altitude. Overset grids are adopted to deal with the relative motion between two different parts. In order to study the security of separating process, the trajectories and attitudes of different parts are calculated and the characteristics of flow field during separation are analyzed carefully. Different initial angles of attack are considered during the simulation and its influence on the separation process is analyzed. The result shows that the initial angle of attack has significant impact on the flow field. Large angle of attack would cause shock/shock interactions between the two parts, threatening the safety of the separating process.

The layer composite rock mass is composed of soft rock and hard rock. The difference of their mechanical characteristics is obvious. It is difficult to describe comprehensively the complicated property with the existent constitutive model. Based on the rheological properties of soft rock and hard rock in the composite rock mass and the creep experiment curves, the rheological model can be used by connecting Burgers model in series with a plastic component. The rheological curves of the composite model under diverse stress level can be attained by multi-staged loading. The simulated result is proved good by comparing the theory curves and the experiment curves. The rheology principium of the complicated rock mass can be illuminated well by the model so that it could be popularly used in engineering practice.

In order to face emergency situation of the rail vehicle air conditioning system, a cool storage device was designed. The device was made up of phase change paraffin and heat exchanger. For the purpose of optimum system design, the mathematic model of phase change and heat transfer in process of cool discharging was established, numerical simulation was finished. Discharging rate of cool and cooling capacity of the device was analyzed. According to the calculation results, the wind speed and air temperature had the greatest influence on the cooling effect, while the thermal conductivity had little effect on it.

As a new technical means, e-commerce provides a new idea for the reform of power supply enterprises. At present, the power company is in the context of economic transformation. To create a world-class power supply enterprise, it is necessary to keep track of the world’s advanced management ideas, methods and means, and integrate the various management services of the enterprise into the increasingly becoming an Internet society. Taking the power supply company of Jilin Province as an example, this paper proposes some improvement schemes for the operation mode of the existing power supply system according to the requirements of the power market for power supply enterprises and the advantages of e-commerce. According to the actual situation of the power supply enterprises in Jilin Province, the network model, structure model and database model of the power supply enterprise, as well as the website design scheme of the e-commerce of the power supply enterprise are designed.

The integrity of oil and gas pipelines is seriously impacted by unstable slopes in tough terrain in western China. The quantitative evaluation technology is an effective method for pipelines risk management under the threat of geohazard. In order to establish the pipeline vulnerability evaluation indexes under effect of unstable slope, the finite element method is adopted to simulate unstable slope movement, pipeline mechanical behavior and pipe-soil interaction by changing geometrical sizes and mechanical characteristics of them, such as the material composition of unstable slope, movement type of unstable slope, diameter and wall thickness pipelines. The regularity for change of stresses and deformations of pipeline subjected to unstable slope can be obtained by means of numerical calculation.

The design of route selection in mountain areas is the foundation and soul of survey and design of suspended monorail transport, which directly determines the project cost, operation cost and so on. As the corresponding technical standards or design specifications of the suspended monorail have not been formally promulgated in China, this paper expounds the structure form and technical characteristics of the suspension monorail, and analyzes the key points of the route selection technology of the suspended monorail in mountain areas in order to provide a reference for the similar project in mountain areas.

The watt balance is operated in two asynchronous measurement modes to obtain the voltage?velocity ratio U/v and the force?current ratio mg/I, respectively. The magnetic flux density will change between the two modes when the effect due to the coil current is taken into account, particularly for watt balances using a soft magnetic material in the magnetic circuit. Normally, the linear component of the magnetic flux density change can be easily eliminated by reversing the coil current; however, the quadratic component remains as a systematic error, i.e. a non-linear error. In this paper, we use a theoretical analysis and a differential finite element method to investigate the behaviour of the quadratic dependence in a typical magnetic circuit. Several strategies are discussed to minimize this error in the magnetic system design for the watt balance.

A quasi-elastic electrostatic oscillation method is proposed for the absolute determination of inertial mass, which is distinguished from the gravitational mass measurement in the watt balance experiment. The value of the kilogram is determined by comparing oscillation periods of the quasi-elastic electrostatic oscillator with different test masses and applying different dc voltages on a symmetrical twin-Kelvin-capacitor system. The required measuring quantities for this method include the capacitance, voltage, vertical distance and oscillation periods, which in principle can be measured with high accuracy. In addition, this experiment is insensitive to the air buoyancy and the heating problem, and it can be operated in air. Both the theory and experimental verifications are presented. (Some figures may appear in colour only in the online journal)

The work aims at understanding the changes in magnetic properties and the magnetoimpedance (MI) effect for the Fe84.5Zr4B8.5Nb2Cu1 (FZBNC) nanocrystalline alloys with the annealing temperature (Ta) from the microstructure point of view. The as-quenched FZBNC ribbons were annealed in a vacuum condition at selected temperatures for 20?min. The microstructures of the specimens were examined by the x-ray diffraction technique. The bcc ?-Fe phase is identified from the XRD patterns. The mean grain size of the ?-Fe phase (D1) at different annealing temperatures (Ta) was estimated using Scherrer's equation. The results show that D1 for the sample annealed at 575??C is about 20?nm, which is the smallest value among all the samples. Measurements on the MI effect reveal that the FZBNC ribbon annealed at 575??C exhibits the most drastic MI ratio of 756% at 600?kHz accompanied by the field sensitivity of 108%?Oe?1, while a large MI effect is not observed in the sample annealed at other temperatures. The origin of the excellent MI effect is investigated in this paper.

The magnetoimpedance (MI) of as-spun amorphous Co72−xFexZr8B20 (CFZB, x = 0, 2, 5, 7 at.%) alloys has been measured at a frequency ranging from 310 to 1110 kHz and a dc magnetic field between 0 to 70 Oe. The maximum MI ratio ΔZ/Z(%)max of the CFZB alloys increases with increasing frequency for each sample and decreases with the increment of Fe content at any frequency. The most drastic MI effect, the maximum value of about 90% at 1110 kHz accompanied by the field sensitivity of 18% Oe−1, is observed in CFZB without Fe. Magnetic measurements reveal that coercivity of CFZB decreases first and then increases with increasing Fe content, and the minimum value of about 1.6 Oe is obtained in the sample with x = 2 at.%. The permeability of CFZB was evaluated from quasi-static hysteresis loops, indicating that the Fe-free CFZB is of the largest permeability. Measurements on electrical resistivity suggest that the Fe-free sample possesses smaller resistivity while the sample with x = 7 at.% has a much larger resistivity compared with CFZB with 2 and 5 at.% Fe. The correlation between MI effect and magnetic properties together with electrical resistivity for the CFZB alloy is discussed in this paper.

Carrier lifetime maps and distributions of doped n-InGaAs in a MBE-grown p-InP/n-InGaAs/n-InP double heterostructure (DH) were measured at 300 K and 85 K using the μ-PCD lifetime screening technique. The theoretical considerations required in this technique are discussed in detail. The average carrier lifetimes are 168.2 ns and 149.4 ns at 300 K and 85 K, respectively. The results are consistent with those of ZnS/n-InGaAs/n-InP DHs. InGaAs lifetime mapping of the InP/InGaAs/InP DH is easily obtained without destruction by μ-PCD carrier lifetime measurement. Therefore, it could be a potential method to characterize the uniformity of the wafers, which is necessary to fabricate InGaAs focal plane arrays (FPAs).

Epitaxial Ti2Ba2CaCu2Ox thin film dc superconducting quantum interference devices (dc SQUIDs) have been fabricated on bicrystal SrTiO3 (STO) substrates. By using the Tl-2212 single phase film, a flux noise density, S-Phi(1/2), of 2.0 x 10(-5)Phi(0) Hz(-1/2) at liquid nitrogen temperature was obtained in the white noise region, which is more than one order of magnitude lower than previous Tl-based SQUIDs made by multiphase thin films. The Tl-2212 thin film bicrystal grain boundary Josephson junctions have demonstrated resistively shunted junction (RSJ) behaviour. The characteristic voltage, VC, which is the product of critical current I-C and junction resistance R-N, was 45 muV at 95 K. The dependence of the critical current on temperature near T-C ( 105 K) was measured as I-C(T) similar to (1 - T / T-C)(1.5-1.98). The dc SQUIDs can operate at temperatures up to 99 K.

In this paper, we establish a model of the micromachined SrTiO3 substrate steps for high-T-c direct-current (dc) superconducting quantum interference devices (SQUIDs). The step angle is determined by the local ion milling rate and re-deposition rate, which is caused by back sputtering of ion milling. At dynamic balance, the maximum possible step angle is predicted to be 75degrees with an ion beam incidence angle of 45degrees, which agrees well with the measured value of 71degrees. In order to obtain a better step sidewall profile, we consider the influences of Nb metal mask micromachining. To avoid a rounded angle at the step upper corner, the minimum thickness of the Nb mask should be 440 nm when the desired step height is 300 nm. At optimized process conditions, steps with sharp, steep angles, and flawless profiles have been fabricated. Nine of the twelve dc SQUIDs thus obtained exhibited resistively shunted junction current-voltage behavior and magnetic field modulation at 77 K.

A novel technique, high temperature high pressure in situ Fourier transform infrared diffuse reflection spectroscopy, was successfully used to investigate the formation and stability of shallow trap states in P25 TiO2 nanoparticles. Two types of shallow traps (with and without H atoms) were identified. The H-containing shallow trap can be easily generated by heating in H2 atmosphere. However, the trap is unstable in vacuum at 600 °C. In contrast, the H-free shallow trap, which can be formed by heating in vacuum, is stable even at 600 °C. The energy gaps between shallow trap states and the conduction band are 0.09 eV for H-containing shallow trap and 0.13 eV for H-free shallow trap, indicating that the H-containing shallow trap state is closer to the conduction band than that without H.

High-spin states in 84Rb have been studied by using the 70Zn (18O, p3n) 84Rb reaction at a beam energy of 75 MeV. The γ - γ coincidence, excitation function and ratios for directional correlation of oriented states were performed. A new level scheme was established in which the positive and negative parity bands have been extended up to 17+ and 17- with excitation energy about 7 MeV. The signature splitting and signature inversion of the positive parity yrast bands were observed and are discussed.

Single-event transient susceptibility of phase-locked loops has been investigated. The charge pump is the most sensitive component of the PLL to SET, and it is hard to mitigate this effect at the transistor level. A test circuit was designed on a 65 nm process using a new system-level radiation-hardening-by-design technique. Heavy-ion testing was used to evaluate the radiation hardness. Analyses and discussion of the feasibility of this method are also presented.

A magnetic-parameter measurement system for study of ferromagnetic materials under high pressure using a diamond-anvil cell is built. The factors affecting the measurement sensitivity are analyzed and the possibility of improving the sensitivity is mentioned. Based on the system, the magnetization curves of iron as a function of pressure are obtained. The start point and end point of pressure-induced magnetic transition of iron are observed at room temperature.

In this paper, a self-sensing carbon nanotube (CNT)/cement composite is investigated for traffic monitoring. The cement composite is filled with multi-walled carbon nanotubes whose piezoresistive properties enable the detection of mechanical stresses induced by traffic flow. The sensing capability of the self-sensing CNT/cement composite is explored in laboratory tests and road tests. Experimental results show that the fabricated self-sensing CNT/cement composite presents sensitive and stable responses to repeated compressive loadings and impulsive loadings, and has remarkable responses to vehicular loadings. These findings indicate that the self-sensing CNT/cement composite has great potential for traffic monitoring use, such as in traffic flow detection, weigh-in-motion measurement and vehicle speed detection.

The luminescence properties of Ce3+ activated Ba2Ca(BO3)2 with K+ as a charge compensator have been investigated and compared with those with Na+-compensating. Energy transfer of Ce3+ in Ba2+ (i.e. Ce(1)3+) and Ca2+ (i.e. Ce(2)3+) sites has been proven by VUV–UV excitation and emission spectra, luminescence decays and time-resolved emission spectra. In addition, by combining Ba2Ca(BO3)2 : Ce3+ phosphors with near-ultraviolet (n-UV) InGaN chips, the fabricated light-emitting diodes (LEDs) show intense bluish-green emission, and the phosphors exhibit good thermal stability.

The spectroscopic properties of Ce3+ activated YBa3B9O18, prepared by a solid-state reaction technique at high temperature, were investigated in the vacuum ultraviolet–ultraviolet range. Though Y–O polyhedra were characterized with regular octahedra in the host YBa3B9O18, five 5d absorption bands were observed due to distorted Ce–O octahedra. The spectroscopic characteristics which include split 5d levels and crystal-field splitting for Ce3+ in the host lattice were interpreted in terms of the crystal structure in combination with centroid shift and spectroscopic polarizability αsp. In addition, temperature and concentration dependence of luminescent properties as well as luminescence decay for YBa3B9O18 : Ce3+ was discussed.