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Oxidative stress is associated with most traumatic or pathological bone defects, and seriously affects the effect of implantation. The construction of antioxidative and osteogenic coatings is of great significance to accelerate the bone regeneration of implants. In this study, baicalein (BAI), a nature flavonoid drug, was loaded in bovine serum albumin (BSA) by desolvent method to prepare BAI-BSA composite protein, and tannic acid (TA)/BAI-BSA coatings were further built via layer by layer self-assembly technology. BAI-BSA possesses good biocompatibility that showed no cytotoxicity to osteoblasts and erythrocytes, and helps to enhance the activity of alkaline phosphatase (ALP) and promote the formation of osteogenic mineralized calcium nodules. After assembled with TA, BAI-BSA coating significantly promoted cell adhesion and in vitro osteogenic mineralization of MC3T3-E1. Moreover, BAI drug loading improved the antioxidative function of BSA coatings effectively. The scavenging rates of (TA/BAI-BSA-10)

A millimeter-band dielectric embedded dual-beam antenna is designed and simulated, which is based on microstrip antenna theory, the Yagi antenna principle and the design method of dielectric embedded microstrip antenna. The antenna buries improved planar printed microstrip Yagi antenna in the dielectric to form a dielectric embedded antenna. The director element of traditional Yagi antenna is changed from one to two, which is used to constrain the beam direction and increase the gain. By using an additional parasitic patch to improve the antenna, a larger relative impedance bandwidth is obtained, and the relative bandwidth is increased from 6.87% to 7.62%, and the gain is 9.96dB, which can be applied to short-distance communication and has good application value.

High-Q dielectric materials ilmenite MgTiO3, columbite MgNb2O6 and cubic perovskite Ba3NiTa2O9 with negative temperature coefficient of resonant frequency (τ f ) were selected as candidates for compensating the τ f of hexagonal perovskite Ba8ZnTa6O24. X-ray diffraction data shows that Ba8ZnTa6O24 coexists with Ba3NiTa2O9 but is not compatible with MgTiO3 and MgNb2O6 at high temperature. The τ f for the mixed hexagonal/cubic perovskite Ba8ZnTa6O24–Ba3NiTa2O9 system is tunable via the temperature compensation effect and its quality factor may be improved via annealing the ceramics at high temperature to enhance the cation ordering in the cubic component. Permittivity e r ~ 22–25, Q×f > 30,000 GHz and tunable τ f within ±10 ppm/°C were achieved in the range of about 50–80 wt% Ba3NiTa2O9 for the hexagonal/cubic perovskite composite Ba8ZnTa6O24–Ba3NiTa2O9 ceramics, which is suitable for the application as dielectric resonators and filters.

A sensitive coefficient was put forward to study the effect of random errors on the directivity of six amplitude-weighted line arrays. Studies show that: random errors cause the loss of directivity, and amplitude weights influence that kind of loss slightly. In addition, that kind of loss has a linearity relationship with the distance between neighboring units; and the larger the line array is, the greater the loss will be.

This paper presents a newly dielectric embedded quasi-microstrip Yagi antenna with barrier (DE-QMYAB). It is a improved structure from dielectric embedded quasi-microstrip Yagi antenna (DE-QMYA).The parasitic patches are arranged nearby each main element patch. So as to the configuration of reflectors are formed. The electromagnetic wave is bared by the parasitic patches. This results in antenna performance improvement, including gain and bandwidth.

This article describes for high power microwave (abbreviation HPM) weapons research from its procedures and developing trends. In the process of researching, developing and using weapons, we have been seeking a real "multi-purpose" weapon which is able to attack the overall target, suitable in all climates and on multi-platform carrier, both for battle field and peace keeping operations. As a result of over twenty years of research, HPM weapons are found to be the optimum answer for all the questions.

The measurement of the target coordinate (estimated value) is one of the main tasks of the FCR (fire control radar). In addition, a high measurement precision is one of the important characteristics of the FCR. So, a study of the optimum signal-measurement of the FCR is of great significance. The Bayes estimation method of average minimum risk and the synthesis of the estimated distance value of the FCR is studied.

The measurement technology of VCM (Vision-based 3-D Coordinate Measurement) has the characteristics of intellectualized measurement and realization of noncontact measurement. It can expand the usage range of 3D coordinate measurement technology. It is the kind of measurement technology which has good development prospects. The process of determining the projection parameters is called calibration. In this paper, the parameters are calibrated without errors.

In this article, a radar with the characteristics of expenditure, short-period of research that can be designed to search and to detect effectively the low-altitude targets in a certain coverage is put forward. As for that of the airborne warning radar, many technological problems should still be worth discussing, especially in the signal-processing area.