Diamond with extraordinary properties, such as fast response, and extremely high thermal conductivity, is an ideal choice for the next generation radiation detectors. In this paper, a radiation detector based on a single crystal CVD diamond (3 mm × 3 mm × 200 μm) with (100) orientation is proposed to detect α radiation. The detector employs gold films on the diamond as an electrical contact, and the origin-symmetric current-voltage characteristics demonstrated excellent Ohmic contact behavior. At an electric field of 0.4 V/μm, a current dark value of 4 nA was measured. The detector's pulse speed was tested using 5.486 MeV 241 Am sources. The time response of the detector to α particles is fast, with a rise time of 260 ps, a fall time of 650 ps, and a pulse width of 1.6 ns. These findings indicate that the detector can be used as a sensor for α radiation.

High precision current measurement is very important for the calibration of various high-precision equipment and the measurement of other precision detection fields. A new current sensor based on diamond nitrogen-vacancy (NV) color center magnetic measurement method is proposed to realize the accurate measurement of current. This new current method can greatly improve the accuracy of current measurement. Experiments show that the linearity of the current sensor based on diamond NV color center can reach up to 33 ppm, which is superior to other current sensors and solves the problem of low linearity. When the range of input current is 5–40 A, the absolute error of the calculated current is less than 51 μA, and the relative error is 2.42 × 10−6 at 40 A. Combined with the research content and results of the experiment, the application of the current sensor in the field of current precision measurement is prospected.

Although single image dehazing has been widely studied as a common low-level computer vision task, it still faces serious challenges such as limited ability to dehaze real foggy pictures. We propose an efficient end-to-end self-adaptation feature attention (SAFA) network with multi-step fusion for this purpose. The proposed SAFA module can adaptively expand the receptive field to obtain the key structure information in space and extract more comprehensive and accurate features. In addition, considering the lack of connection between features acquired at low and high levels in the network, we also implement a multi-step fusion module, which makes the features of different layers in the network complementary effectively in the process of image recovery. The network structure is simplified, and the required computing resources are significantly reduced by decreasing network parameters. For multiple datasets and photographs with real haze, our method demonstrates better efficiency and availability, both quantitatively and qualitatively.

A compact deuterium–deuterium neutron generator for prompt gamma neutron activation analysis was developed at Institute of Nuclear Physics and Chemistry. A neutron yield of 3.6 × 108 s–1 was achieved during of the bombardment of a titanium drive-in target by a 6.8 mA deuteron beam at 115 keV. The deuteron beam was generated by a permanent magnet microwave ion source. An 85 h long run with 1.2 × 108 s–1 average neutron yield was performed at 85 keV and 3.7 mA. The operating mode of the neutron generator reached 99.95%.

The resonant optical gyro system requires the laser tracking to lock the resonant frequency for angular velocity detection, but there exists the optical power fluctuation problem in the semiconductor laser used in it.Affected by the residual intensity modulation of phase modulator, the center of demodulation curve of the system will be offset, resulting in lock-in deviation of the gyroscope system and long-term drift of the output path.In this regard, the simulation and experimental test are carried out in this paper.And by calibrating the optical power and the center point of the demodulation curve, the linear relationship between the two is obtained, and the gyro output error caused by the optical power fluctuation can be eliminated through real-time detection of the lock frequency point of the optical power compensation gyro system.In this scheme, the bias stability of the gyroscope system is tested to be 80 (°) /h, and the output path has no drift, which can improve the long-term working stability of the gyro system.

谐振式光学陀螺需要使用激光器频率锁定技术实现其中一路的频率锁定,探测另一路的谐振频率。在实现激光频率锁定后,陀螺系统会受环境因素的影响在锁频环路中产生超低频漂移,传统的比例积分伺服控制器产生的增益不能够抑制该漂移。本文采用一路为传统的比例积分控制器,另一路为低通滤波器与积分控制器,两路共同作用形成新型伺服控制器进行激光器的频率锁定,提高锁频环路的低频增益,抑制锁频路产生的超低频漂移,通过仿真理论证明其可行性,并进行系统测试,测得锁频环路中的Allan方差值为0.005°/s,且锁频路基本无漂移。

本文针对电磁法在深部找矿中的应用,结合理论实践,在简要阐述电磁法探测原理的基础上,分析了电磁法在深部找矿中的应用现状,接着论述了电磁法的数据处理方法,最后分析研究了电磁法在深部找矿中的具体应用.分析结果表明,在深部找矿中科学合理的应用电磁法,能有效提升找矿的精度和效率,而且操作比较方便,符合目前我国深部找矿相关规范和标准的要求,值得大范围推广应用.

A highly sensitive,fast and portable detection method for the micro food additives based on surface-enhanced Raman scattering (SERS) effect was proposed.Using the fiber ball structure,a highly sensitive and portable SERS signal detection probe based on the fiber ball structure coated with the silver nanoparticles was designed and developed.The parylene-C nanofilm was coated on the silver nanostructure to achieve the repeatability application and test of the probe.In the experiment,when the laser was inputted from the fiber probe end,the silver nanostructure on the probe surface was excited to enhance the Raman signals of the food additives.Then the Raman signals were gathered by the fiber ball,and were collected and tested through the end of the fiber probe.The detection of the micro R6G molecular with the concentration of 10-12 mol/L was realized,and the detection of the food additives in usual food was also realized.This probe has the portability,high efficiency,rapidity,high sensitive detection characteristics,and can be widely used to improve the detection ability of the food safety.

介绍了谐振式光学陀螺的系统构建及工作原理。针对谐振式光学陀螺系统中引入白噪声而影响其转动输出精度问题,该文从理论上对该系统中各信号间的互相关性原理进行了分析,并提出了一种采用数字低通滤波器对信号进行噪声滤除的处理方式。通过对该陀螺系统进行转动测试和零偏稳定性测试。研究发现,其转动输出信号幅度范围用数字量表示由原来的300减小到60。利用Allan方差对零偏稳定性测试数据进行拟合计算,得出其输出精度由265.29（°）/h提高到62.96（°）/h,结果表明,该系统输出精度得到有效提高。

A acceleration sensing method based on the ultrahigh resolution detection mechanism of the magnetic gradient field of the permanent magnet was reported.In the experiment,by embedding the permanent magnet on the upper surface of the polydimethylsiloxane (PDMS) flexible film material center and fixing the periphery of the PDMS film,the permanent magnet was suspended,and then the cantilever beam type permanent magnet mass block structure was prepared.The linear distribution region of the magnetic gradient field for the permanent magnet was obtained by the simulation,and the magnetic detection unit was fixed in the linear region of the magnetic gradient field.By detecting the magnetic field variation caused by the micro displacement of the permanent magnet under the acceleration,the sensing detection of the acceleration information was realized.The static test results show that in the range of 0.866g-1g,the acceleration sensing sensitivity is 4.68 Gs/g,and the acceleration detection resolution is approximate to 93μg.

为了更简单地制备出可用于应力测量的光栅褶皱结构,采用基于刚性薄膜/柔性衬底的自组装工艺制备了可调谐光栅。首先在聚乙烯对苯二酸脂（PET）薄膜上旋涂一层聚二甲基硅氧烷（PDMS）薄膜,将双层薄膜弯曲并用氧气等离子体处理,在其表面生成一层刚性氧化层,借助柔性PET对刚性层施加均匀应力,当应力超过临界值时,在PDMS基底上自组装形成光栅褶皱结构。然后根据光栅分光原理,将这种可调谐的光栅结构应用于应力测试。实验结果表明:当光栅的曲率半径为1.4mm时,制备的可调谐光栅褶皱在0%~10%的应变范围得到的波长变化为452~507nm;当光栅的曲率半径为5.6mm时,制备的可调谐光栅褶皱在0%~15%的应变范围得到的波长变化为498~572nm。本文提出的可调谐光栅制备方法是一种成本低、工艺简单、可批量化生产的工艺方法,也是一种制备变间距光栅的潜在方法,未来有望应用于光谱仪、光通讯等领域。

MEMS vibratory gyroscope has been widely used in military, automotive, and consumer electronics fields for its small size, low power consumption, high reliability, and impact resistance. Particularly, as one of the main directions of domestic and foreign research in the field of micro-gyroscope, the axial symmetry micro vibration gyroscope has higher quality factor, smaller frequency division and many other excellent characteristics. This paper gives a brief introduction of several typical structures of axial symmetry micro vibration gyroscope, then introduces the simulation and testing experiments of some axial symmetry micro vibration gyroscope we designed.

为实现谐振式光学陀螺中现场可编程门阵列（FPGA）主控芯片与上位机之间的数据传输需求,便于实时调整陀螺的各项参数、优化陀螺的工作状态。该文采用全双工通信RS422串口与USB接口实现了基于FPGA的谐振式光学陀螺数字检测系统与MATLAB上位机的连接。在分析了陀螺的工作原理的基础上,重点开展了RS422串口在陀螺系统中的软硬件和上位机通信功能设计。实验结果表明,该数据传输系统工作稳定,灵活可靠,能较好地实现谐振式光学陀螺与MATLAB上位机间的数据传输。

深部找矿—直以来难度较大且缺乏有效的手段,金属矿测井作为找矿手段已应用多年,但其深部找矿应用尚在探索中,效果也有待于评价.本文以福建省尤溪县梅仙镇峰岩—谢坑矿区钻孔测井资料为研究对象,解剖了三分量磁测、电阻率测井和激电测井等方法在该区深部找矿中的应用.通过对比钻孔取芯观察分析,对矿化段识别效果和多种测井响应特征进行了综合分析,认为在本区的几种测井方法中,电阻率测井对铅锌矿的识别效果稍好,磁测对部分矿体品位高的铅锌矿的识别井段有好的显示;总体上两种测井方法都分别有一定的显示效果,但对深部的钼矿井段显示都不好,也不存在对应关系.综合分析测井在该区深部找矿中的应用,认为要做好深部找矿应首先分析好测井应用条件是否合适,在矿产勘查过程中运用更为有效的测井手段探测与矿化的对应关系,有助于减少区域找矿工作的盲目性,适合条件的钻孔测井方法在发现和预测深部矿体,确定矿体产状,圈定矿体规模,指示矿体空间位置等方面可以起到一定的辅助作用,提升找矿成功率.

The principle of magnetic mass spectrometer is briefly introduced.According to types of equipment included in the magnetic mass spectrometer,a two-layer structure of control system based on Ethernet is designed.The basic functions of re-mote adjustment and monitor of parameters and interlock protection are realized.A set of trigger system is designed for a continu-ously adjustable delay time of 0~20 μs.Through the test,the system has obtained the spectral graph which satisfies the physical experiment requirements.After dozens of hours of experimental test,the system is stable and operable,which satisfactorily meets the user's experimental needs.

According to the application requirements of precision guidance,a "sandwich" capacitive accelerometer sensor with the range of 100g was designed.Using the ANSYS simulation software,the stress analysis and modal analysis were carried out under high overload conditions of 100g and 10 000g.The size of the sensitive structure of the accelerometer sensor was obtained by the MATLAB analysis and optimal structure parameters.The analysis results of the impedance analyzer show that the static capacitance of the sensor is 14.09 pF,the output sensitivity of the structure is 0.281 8 pF/g,the sensitivity of the sensor is 13.5 μV/g.According to the structural characteristics of the accelerometer sensor,the process flow was designed and the key processes were carried out,including the double-sided wet etching based on silicon,ICP dry etching and glass through-hole electroplating.Finally,the design feasibility of the capacitive accelerometer sensor was verified by experiments.

A new method was proposed to improve the microwave quality factor by using optical resonant cavities instead of long optical fibers as the delay device of optoelectronic oscillators.In this scheme,the photons can be circularly transmitted in the resonant cavity for many times.A 2 inches (1 inch =2.54 cm) plane waveguide resonator cavity can make the system produce the optimal microwave signal with the photon delay of 1 923.1 ns and output spectrum width of 0.52 MHz.The microwave quality factor reaches 12 077.1,and the delay effect of the optical resonant cavity is equivalent to that of the 388.7 m long fiber.By adding an optical waveguide resonant cavity in the system,the 1.2 GHz microwave signal with the phase noise of-93 dBc/ Hz@10 kHz at the center frequency of 1.2 GHz is generated.The advantages of this scheme are that using of optical resonant cavities instead of long optical fibers as the delay devices of optoelectronic oscillators can reduce the susceptibility of the long fiber to the environmental temperature and stress and decrease the phase noise of microwave signals.

The quality factor (Q) is an important parameter of the optical resonant cavity,and the large-size planar ring resonant cavity has larger single-lap loss,but has higher Q value.To solve this problem,the modeling analysis and simulation of the coupling structure of the ring resonant cavity were carried out based on the photon lifetime.The relation between the cavity length and the quality factor was characterized by using the equivalent unit transmission loss parameters.The silica optical waveguide-type ring resonant cavities with different cavity lengths (3.1,9.5,12.6 and 18.8 cm) were designed and fabricated,in which the coupling coefficient of the resonant cavity was kept constant.The test results show that with the increase of the cavity length,the equivalent unit transmission loss of the resonant cavity decreases and the Q value increases,which are consistent with the simulation results.This conclusion provides a new approach for the study of the optical waveguide resonant cavity with high Q value.

The amount of exposure received by the imaging device and the sensitivity of the device all had crucial impacts to the image quality and the polarization information in the polarization imaging technology. We analyzed the influence to the sky polarization information when changed the amount of exposure and the sensitivity of the imaging device respectively. In the sunny weather day,device is easy to overexposure,so the approach to be first taken was to reduced the amount of exposure.Experiments show that when reduced the amount of exposure by 5 times,the accurate of polarization information can be increased 48%. Secondly,the device sensitivity was changed by controlling the ISO degree. Experiments show that when each ISO level is lower in one grade,the similarity can be increased 5%. And the similarity can be achieved the maximum when the ISO is 100,the measurement accuracy can be up to about 70%.

To reduce the influence of the temperature change of filter based on micro ring resonator,study tempera?ture properties of micro-ring resonator,the simple ring and cascaded rings resonators based on silicon-on-insulator was designed and fabricated. The micro-ring resonators were heated by temperature controller and the transmission spectrum shift was observed via the vertical grating coupling method and the wavelength scanning way. From the theoretical analysis,experimental test and linear simulation,it has been concluded that the temperature coefficient is 105 pm/℃,97 pm/℃and 80 pm/℃,27 pm/℃in simple ring,double rings,triple rings and nine rings,respective?ly. In a word,the sensitivity to temperature is decreased and the temperature drift is inhibited with the increase of the number of rings.