输入信号时序鉴别方法与电路研究

简要介绍一种新的输入信号时序鉴别方法与电路。该电路的主要功能是对输入信号的时序进行鉴别和分拣,它可以鉴别出一个输入信号串中包含的各个脉冲的序号,并且产生与各个序号相对应的输出信号。可以鉴别的输人信号的序号为N=1,2,3,…,8。适用于多路时间幅度转换器(TAC)和多路时间数字转换器(TDC)系统,其输出信号可作TAC和TDC的停止信号。该电路输出信号的前沿tr≤3.2ns,传输延迟tpd≤20ns.

两种保护剂对C离子诱导小鼠急性肝损伤的应答；Response of Two Protective Agents to Acute Injury Induced by ~(12)C~(6+) Ions in Mouse Liver

比较了N-乙酰半胱氨酸(NAC)及乙酰左旋肉毒碱(ALCAR)对12C6+离子照射小鼠的损伤效应,并探讨了其可能的作用机制。利用4Gy剂量的12C6+离子束对预先给予NAC(100mg/kg)和ALCAR(100mg/kg)保护的昆明小鼠进行单次全身照射。随后检测肝组织中总抗氧化能力(TAC)、DNA单链断裂和细胞凋亡率。结果显示,与照射对照组相比,提前给予NAC和ALCAR均极显著地增强了肝组织的抗氧化能力(P<0.001),减轻了12C6+离子导致的肝组织中DNA断裂(P<0.001)和细胞凋亡(P<0.001)。此外,还发现ALCAR组抗重离子辐照损伤的能力显著地高于NAC组(P<0.05)。实验结果提示了NAC和ALCAR可通过抵御组织内的氧化胁迫,阻止DNA链的断裂和细胞的凋亡,实现对C离子辐照损伤的保护效应。而且ALCAR比NAC可能更适合成为有潜力、有希望的抗C重离子辐射药物。

中子墙探测器前端电子学研究

随着国家大科学工程兰州重离子加速器冷却储存环(HIRFL-CSR)建成，CSRm实验探测系统也正在建设当中。CSRm实验探测系统由外靶系统和内靶系统构成。外靶系统主要有γ探测器、多丝漂移室（MWDC）、ToF墙(ToF Wall)、中子墙（Neutron Wall）等探测器组成，主要用于核物理研究。其中，用于探测中子的中子墙探测器是外靶系统中的一个重要组成部分，它有252个探测单元，每一个探测器单元都要求既有很好的能量分辨，也要有很好的时间分辨，同时还要求数据获取率达到每秒几千个事件。对于这样先进的探测器和大型实验探测系统采用传统的电子学仪器和方法已经无法构成读出电子学系统，建造与之相配的读出电子学系统是极为重要的和亟待解决的工作。为此，我们设计研发适合于中子墙探测器这样的大型闪烁体探测器的前端电子学读出系统。包括三大部分：16道电荷幅度转换电路（QAC），16道时间幅度转换电路（TAC）和有效信号判断电路。本论文的主要内容如下：在第一章绪论中，介绍了论文课题的出发点以及课题的意义，并对课题的背景进行了介绍。第二章介绍我们所自行设计的中子墙探测器的特点、结构。分析了中子墙探测器的输出信号的特点以及对后续前端电子学读出系统的要求。第三章是本论文两大核心部分之一，是本论文的创新点所在。主要介绍了我们电荷幅度转换的新方法，结合通常的QAC电路方法和具体的实际情况，我们自行提出了一种新的QAC电路，包括以下几个部分：差分输入电路、电流分割、上下恒流源、门控电流积分器。我们的创新点在于，我们用上下恒流源分别代替了通常QAC中作为电流分配的电流镜像和作为电流基准的电阻，这样一来更容易得到比较稳定的偏置电流，从而能够得到更高的转换精度。第四章是本论文的另外一个核心部分，首先我们论述了核电子学时间测量的几种方法，在对它们进行对比后，结合中子墙的实际特点，我们确定了采用起停型的TAC方法。然后介绍了TAC的原理，以及具体的电路结构。第五章主要的内容是对我们整个电路的逻辑电路进行了详细的介绍，它包括16道QAC和16道TAC的积分控制信号和泄放控制信号的产生电路以及有效信号判断电路。详细论述了这些逻辑关系以及如何在CPLD实现，并且给出了仿真结果。第六章详细讨论了我们在设计PCB板时遇到的问题及其解决方法。第七章介绍了多路QAC和多路TAC主要指标及其测试方法、步骤、结果并给出了误差分析。在总结部分我们回顾了我们整个工作的过程，介绍了论文的主要成果和创新点以及对于整个CSR工程的意义。本论文的创新点： 1、提出了一种新型的QAC电路。 2、将16道QAC和16道TAC以及有效信号判断电路集成在一个插件中提高了电路的集成度，并为最终集成在一片ASIC芯片中打下坚实的基础。 3、用可编程逻辑器件代替ECL器件来构建逻辑电路，降低了功耗和成本并提高了系统的可靠性

多通道电荷时间测量方法与电路研究

随着国家大科学工程兰州重离子加速器冷却储存环(HIRFL-CSR)建成，HIRFL-CSR实验探测系统也正在建设当中。实验探测系统由外靶系统和内靶系统构成。用于探测中子的中子墙探测器是外靶系统中的一个重要组成部分，它有252个探测单元，每一个探测器单元都要求很好的能量分辨和时间分辨，还要求有很高数据获取率。为此，我们设计研发适合于中子墙探测器这样的大型闪烁体探测器的前端电子学读出系统。论文从发展髙性能多路小型化前端电路和研究QAC、TAC的方法和电路两个方面进行研究，讨论了我们采用的新思路和新方法。 我们设计的新型的多道高精度的电荷-电压、时间转换电路.该电路主要用于在相关控制信号的配合下，将光电倍增管输出的快电流脉冲信号转化为电压信号,并在控制信号作用下,将电压信号通过数据采集系统直接送入计算机进行处理。电路采用新型的QAC方法，用于处理快速的电流信号,突出特点是转换速度快,电路结构简单,输入信号范围大,精度高,功耗低, 电路采用改进的TAC方法，用于处理快速的时间信号,利用高速DMOS开关，并优化控制逻辑时序，极大提高了测试精度。 实验室调试结果说明系统已能够适应物理实验的要求，并为最终建立一个完整的满足性能要求的前端电子学系统打下了坚实的基础

用于在线同位素分离器的激光离子源的研制

本文介绍了一种新型的用于在线同位素分离器的离子源——激光离子源。这种离子源将会大大提高在线同位素分离器的化学选择性，给新核素的合成及其衰变性质研究注入巨大的活力。论文首先介绍了激光离子源的工作原理和国际上研制激光离子源的情况。其次介绍了我们在研制热管式激光离子源方面取得的以下进展：(1)激光器系统已经可以使用，完成了光路传输与合成系统；（2）研制了一个用于研究激光离子源特性的离线实验装置；(3)获得了铥元素的激光多步共振电离信号，测量了Ta，Nb-Zr合金和内表面涂有了TaC的Nb-Zr合金电离管表面电离电流及激光共振电离电流随温度纷变化曲线，得到了热管式激光离子源的化学选择性，对元素铥的化学选择性可达封50-10000，论文最后对将要做的工作提出了进一步的设想，对激光离子源的前景做了展望。

Dynamic mechanical and thermal properties of plasticized poly(lactic acid)

The blends of low molecular weight triacetin (TAC) and oligomeric poly(1,3-butylene glycol adipate) (PBGA) were used as multiple plasticizers to lubricate poly(lactic acid) (PLA) in this study. The thermal and mechanical properties of plasticized polymers were investigated by means of dynamic mechanical analysis and differential scanning calorimetry. Atomic force microscopy (AFM) was used to analyze the morphologies of the blends. Multiple plasticizers were effective in lowering the glass transition temperature (T-g) and the melting temperature (T-m) of PLA. Moreover, crystallinity of PLA increased with increasing the con-tent of multiple plasticizers. Tensile strength of the blends decreased following the increasing of the plasticizers, but increased in elongation at break. AFM topographic images showed that the multiple plasticizers dispersed between interfibrillar regions. Moreover, the fibrillar crystallite formed the quasicrosslinkings, which is another cause for the increase in elongation at break.

Comparison of photobioreactors and optimal light regime for rapid vegetative propagation of transgenic Undaria pinnatifida gametophytes

BACKGROUND: Previously, tachyplesin gene (tac) has been successfully transferred into Undaria pinnatifida gametophytes using the method of microprojectile bombardment transformation. The objectives of this study were to compare and evaluate the performance of bubble-column and airlift bioreactors to determine a preferred configuration of bioreactor for vegetative propagation of transgenic U. pinnatifida gametophytes, and to then investigate the influence of light on vegetative propagation of these gametophytes, including incident light intensity, photoperiod and light quality to resolve the problems of rapid vegetative propagation within the selected bioreactor. RESULTS: Experimental results showed that final dry cell density in the airlift bioreactor was 12.7% higher than that in the bubble-column bioreactor under the optimal aeration rate of 1.2 L air min(-1) L-1 culture. And a maximum final dry cell density of 2830 mg L-1 was obtained within the airlift bioreactor using blue light at 40 mu mol m(-2) s(-1) with a light/dark cycle of 14/10 (h). Polymerase chain reaction (PCR) analysis indicated that genes (bar and tac) were not lost during rapid vegetative propagation within the airlift bioreactor. CONCLUSION: The airlift bioreactor was shown to be much more suitable for rapid vegetative propagation of transgenic U. pinnatifida gametophytes than the bubble-column bioreactor in the laboratory. The use of blue light allows improvement of vegetative propagation of transgenic U. pinnatifida gametophytes. (C) 2009 Society of Chemical Industry

A new method for the estimation of oceanic mixed-layer depth using shipboard X-band radar images

Shipboard X-band radar images acquired on 24 June 2009 are used to study nonlinear internal wave characteristics in the northeastern South China Sea. The studied images show three nonlinear internal waves in a packet. A method based on the Radon Transform technique is introduced to calculate internal wave parameters such as the direction of propagation and internal wave velocity from backscatter images. Assuming that the ocean is a two-layer finite depth system, we can derive the mixed-layer depth by applying the internal wave velocity to the mixed-layer depth formula. Results show reasonably good agreement with in-situ thermistor chain and conductivity-temperature-depth data sets.

转基因海带配子体的制备与高效增殖

海带具有很高的营养价值和经济社会价值。自20世纪90年代以来，本实验室在借鉴高等植物基因工程原理和方法的基础上，根据海带自身特点，建立了海带遗传转化体系（海带孢子体表达系统），它的基本原理是利用基因枪法转化海带配子体，经孤雌或受精途径再生幼孢子体后，用氯霉素筛选幼孢子体获得转基因海带，然后进行海上安全栽培和转基因产品的检测与提取。目前该表达系统已成功实现报告基因（β-半乳糖苷酶基因，lacZ）和功能基因（乙肝表面抗原基因，HBsAg）的稳定表达。 由于海带孢子体表达系统需经孢子体再生和海上栽培等阶段，周期较长，而且转基因安全性问题也在一定程度上制约其研究与应用。因此，我们在海带孢子体表达系统的基础上又建立和优化了海带配子体表达系统，并成功实现了报告基因（绿色荧光蛋白基因，GFP）的瞬间表达和功能基因（瑞替普酶基因，rt-PA）的稳定表达。虽然海带配子体表达系统能避免转基因安全性问题，周期较短，但在表达量和生物量积累方面，与孢子体表达系统相比还有较大差距。 本文首先在海带配子体表达系统中成功实现了人酸性成纤维细胞生长因子基因（hafgf）和鲎素基因（tac）的稳定表达，制备了转基因海带配子体，然后将光生物反应器培养技术应用于转基因海带配子体的高效增殖，以期解决阻碍海带配子体表达系统发展的量的问题，并为转基因海带配子体的大规模培养提供试验依据和技术支持。 本文的研究结果为： 1、人酸性成纤维细胞生长因子基因和鲎素基因可以稳定整合到海带配子体基因组中，实现转基因产物的表达。 2、根据转基因海带配子体的生长特点，研制开发了一套培养体积为300 ml的鼓泡式光生物反应器，它具有操作简便、成本低廉、适合海带配子体生长等特点。随后将培养体系扩大到2.5 L，并研究了光对转基因海带配子体生长的影响，试验结果显示，转基因海带配子体在光强为30 μE m-2 s-1时即可达到光饱和生长，最优光周期为14:10 LD，而且蓝光可促进转基因海带配子体的生长。 3、在前期研究工作的基础上，为改善反应器内的传质条件，我们又设计研制了2.5 L气升式光生物反应器用于转基因海带配子体的高效增殖。研究发现，气升式光生物反应器较鼓泡式光生物反应器能明显地改善反应器内的传质状态，实现转基因海带配子体更高密度的培养（生物量可达到1,990 mg L-1），是一套高密度悬浮培养转基因海带配子体的有效装置和设备。

一种快速获取激光拼焊焊缝错配的新算法

本文讨论了基于视觉和结构光的焊缝形貌视觉检测系统的组成原理,针对拼板激光焊接工程中对焊缝检测的实时性要求高的特点,创新性地提出了一种快速获得焊缝错配缺陷的算法,主要步骤为:首先基于有关标准的检测指标阈值的设定,再次,针对在线提取到的图像进行预处理,主要是加窗和中值滤波;最后为Radon变换与错配检测。该算法能减少计算任务,从而快速获得错配检测指标。实验给出了不等厚板拼焊时的线性错配的数值和分布,同时验证了该算法的有效性。

叠前地震数据规则化、重建及噪音压制

I address of reconstruction of spatial irregular sampling seismic data to regular grids. Spatial irregular sampling data impairs results of prestack migration, multiple attenuations, spectra estimation. Prestack 5-D volumes are often divided into sub-sections for further processing. Shot gathers are easy to obtain from irregular sampling volumes. My strategy for reconstruction is as follows: I resort irregular sampling gathers into a form of easy to bin and perform bin regularization, then utilize F-K inversion to reconstruct seismic data. In consideration of poor ability of F-K regularization to fill in large gaps, I sort regular sampling gathers to CMP and proposed high-resolution parabolic Radon transform to interpolate data and extrapolate offsets. To strong interfering noise--multiples, I use hybrid-domain high-resolution parabolic Radon transform to attenuate it. F-K regularization demand ultimately for lower computing costs. I proposed several methods to further improve efficiency of F-K inversion: first I introduce 1D and 2D NFFT algorithm for a rapid calculation of DFT operators; then develop fast 1D and 2D CG method to solve least-square equations, and utilize preconditioner to accelerate convergence of CG iterations; what’s more, I use Delaunay triangulation for weight calculation and use bandlimit frequency and varying bandwidth technique for competitive computation. Numerical 2D and 3D examples are offered to verify reasonable results and more efficiency. F-K regularization has poor ability to fill in large gaps, so I rearrange data as CMP gathers and develop hybrid-domain high-resolution parabolic Radon transforms which be used ether to interpolate null traces and extrapolate near and far offsets or suppress a strong interfere noise: multiples. I use it to attenuate multiples to verify performances of our algorithm and proposed routines for industrial application. Numerical examples and field data examples show a nice performance of our method.

叠前时间偏移：各向异性、多次波衰减及应用

At present, in order to image complex structures more accurately, the seismic migration methods has been developed from isotropic media to the anisotropic media. This dissertation develops a prestack time migration algorithm and application aspects for complex structures systematically. In transversely isotropic media with a vertical symmetry axis (VTI media), the dissertation starts from the theory that the prestack time migration is an approximation of the prestack depth migration, based on the one way wave equation and VTI time migration dispersion relation, by combining the stationary-phase theory gives a wave equation based VTI prestack time migration algorithm. Based on this algorithm, we can analytically obtain the travel time and amplitude expression in VTI media, as while conclude how the anisotropic parameter influence the time migration, and by analyzing the normal moveout of the far offset seismic data and lateral inhomogeneity of velocity, we can update the velocity model and estimate the anisotropic parameter model through the time migration. When anisotropic parameter is zero, this algorithm degenerates to the isotropic time migration algorithm naturally, so we can propose an isotopic processing procedure for imaging. This procedure may keep the main character of time migration such as high computational efficiency and velocity estimation through the migration, and, additionally, partially compensate the geometric divergence by adopting the deconvolution imaging condition of wave equation migration. Application of this algorithm to the complicated synthetic dataset and field data demonstrates the effectiveness of the approach. In the dissertation we also present an approach for estimating the velocity model and anisotropic parameter model. After analyzing the velocity and anisotropic parameter impaction on the time migration, and based on the normal moveout of the far offset seismic data and lateral inhomogeneity of velocity, through migration we can update the velocity model and estimate the anisotropic parameter model by combining the advantages of velocity analysis in isotropic media and anisotropic parameter estimation in VTI media. Testing on the synthetic and field data, demonstrates the method is effective and very steady. Massive synthetic dataset、2D sea dataset and 3D field datasets are used for VTI prestack time migration and compared to the stacked section after NMO and prestack isotropic time migration stacked section to demonstrate that VTI prestack time migration method in this paper can obtain better focusing and less positioning errors of complicated dip reflectors. When subsurface is more complex, primaries and multiples could not be separated in the Radon domain because they can no longer be described with simple functions (parabolic). We propose an attenuating multiple method in the image domain to resolve this problem. For a given velocity model，since time migration takes the complex structures wavefield propagation in to account, primaries and multiples have different offset-domain moveout discrepancies, then can be separated using techniques similar to the prior migration with Radon transform. Since every individual offset-domain common-reflection point gather incorporates complex 3D propagation effects, our method has the advantage of working with 3D data and complicated geology. Testing on synthetic and real data, we demonstrate the power of the method in discriminating between primaries and multiples after prestack time migration, and multiples can be attenuated in the image space considerably.

基于信息重建技术的地震信号处理方法研究

The dissertation addressed the problems of signals reconstruction and data restoration in seismic data processing, which takes the representation methods of signal as the main clue, and take the seismic information reconstruction (signals separation and trace interpolation) as the core. On the natural bases signal representation, I present the ICA fundamentals, algorithms and its original applications to nature earth quake signals separation and survey seismic signals separation. On determinative bases signal representation, the paper proposed seismic dada reconstruction least square inversion regularization methods, sparseness constraints, pre-conditioned conjugate gradient methods, and their applications to seismic de-convolution, Radon transformation, et. al. The core contents are about de-alias uneven seismic data reconstruction algorithm and its application to seismic interpolation. Although the dissertation discussed two cases of signal representation, they can be integrated into one frame, because they both deal with the signals or information restoration, the former reconstructing original signals from mixed signals, the later reconstructing whole data from sparse or irregular data. The goal of them is same to provide pre-processing methods and post-processing method for seismic pre-stack depth migration. ICA can separate the original signals from mixed signals by them, or abstract the basic structure from analyzed data. I surveyed the fundamental, algorithms and applications of ICA. Compared with KL transformation, I proposed the independent components transformation concept (ICT). On basis of the ne-entropy measurement of independence, I implemented the FastICA and improved it by covariance matrix. By analyzing the characteristics of the seismic signals, I introduced ICA into seismic signal processing firstly in Geophysical community, and implemented the noise separation from seismic signal. Synthetic and real data examples show the usability of ICA to seismic signal processing and initial effects are achieved. The application of ICA to separation quake conversion wave from multiple in sedimentary area is made, which demonstrates good effects, so more reasonable interpretation of underground un-continuity is got. The results show the perspective of application of ICA to Geophysical signal processing. By virtue of the relationship between ICA and Blind Deconvolution , I surveyed the seismic blind deconvolution, and discussed the perspective of applying ICA to seismic blind deconvolution with two possible solutions. The relationship of PC A, ICA and wavelet transform is claimed. It is proved that reconstruction of wavelet prototype functions is Lie group representation. By the way, over-sampled wavelet transform is proposed to enhance the seismic data resolution, which is validated by numerical examples. The key of pre-stack depth migration is the regularization of pre-stack seismic data. As a main procedure, seismic interpolation and missing data reconstruction are necessary. Firstly, I review the seismic imaging methods in order to argue the critical effect of regularization. By review of the seismic interpolation algorithms, I acclaim that de-alias uneven data reconstruction is still a challenge. The fundamental of seismic reconstruction is discussed firstly. Then sparseness constraint on least square inversion and preconditioned conjugate gradient solver are studied and implemented. Choosing constraint item with Cauchy distribution, I programmed PCG algorithm and implement sparse seismic deconvolution, high resolution Radon Transformation by PCG, which is prepared for seismic data reconstruction. About seismic interpolation, dealias even data interpolation and uneven data reconstruction are very good respectively, however they can not be combined each other. In this paper, a novel Fourier transform based method and a algorithm have been proposed, which could reconstruct both uneven and alias seismic data. I formulated band-limited data reconstruction as minimum norm least squares inversion problem where an adaptive DFT-weighted norm regularization term is used. The inverse problem is solved by pre-conditional conjugate gradient method, which makes the solutions stable and convergent quickly. Based on the assumption that seismic data are consisted of finite linear events, from sampling theorem, alias events can be attenuated via LS weight predicted linearly from low frequency. Three application issues are discussed on even gap trace interpolation, uneven gap filling, high frequency trace reconstruction from low frequency data trace constrained by few high frequency traces. Both synthetic and real data numerical examples show the proposed method is valid, efficient and applicable. The research is valuable to seismic data regularization and cross well seismic. To meet 3D shot profile depth migration request for data, schemes must be taken to make the data even and fitting the velocity dataset. The methods of this paper are used to interpolate and extrapolate the shot gathers instead of simply embedding zero traces. So, the aperture of migration is enlarged and the migration effect is improved. The results show the effectiveness and the practicability.

中国地下工程氡污染健康影响与防护研究-以内蒙古自治区为例

由于对人体健康的危害，氡越来越受到世界各国的广泛关注。经济的发展，使我国地下公共场所大量涌现，但其空气中氡浓度的大规模调查及系统研究还属空白。本论文采取瞬时法（美国SUN公司的1027型连续测氰仪）与累积法（CR一39SSNTD）相结合的测量方法，对我国23个城市的地下工程进行了为期一年的监测，获得了实测数据700多个。在监测的同时，收集了每个测点的各种相关情况资料。论文以内蒙古自治区的呼和浩特、包头、集宁、鄂尔多斯四个城市为例，从环境地球化学角度出发，在研究了各个测点的各种情况之后，探讨了氧在不同类型工程和不同城市的浓度规律。对长期有人在内工作的地下工程内氛所致工作人员的有效剂量当量进行了估算。最后对氨异常的测点进行了原因分析，并提出了地下工程内氰污染的治理和防范措施。本次研究主要得出以下结论：1、地下工程中氰浓度的季节变化规律为：从总平均值看，夏高冬低。与前人对坑道的调查结果一致，与地上氨浓度的变化规律相反。从两季浓度差来看，两季浓度差从大到小依次为：隧道类工程）单建式铜室类工程＞结建式嗣室类工程。2、总体来看内蒙三类工程的氰浓度值：隧道类工程）结建式铜室类工程）单建式铜室类工程。不管是单季还是年平均值，各城市三类工程的氧浓度都遵循隧道类．工程远大于结建式铜室工程和单建式铜室工程的规律。通过对结建式桐室工程和单建式铜室工程的对比分析，发现在地下工程内工程上部有无建筑物阻隔，并不是影响氨浓度高低的重要因素，即氰的纵向扩散作用小于横向扩散作用。3、呼和浩特、包头、集宁、鄂尔多斯四个城市的氛浓度年平均值分别为：190Bq／m3、700Bq／m3、190Bq／m3、270Bq／m3。去掉仅有一季结果的侧点值，包头、鄂尔多斯的氨浓度年平均值为：62oBq／m3、250Bq／m3。呼和浩特、包头、集宁、鄂尔多斯四个城市的氛浓度单季值的范围分别为：31-830Bq／m3、57-3500Bq／m3、26一65oBq／m，、64一69OBq／m'，；年平均值的范围分别为：39一580Bq／m：'、94一210oBq／m：，、35-460Bq／m3、110-390Bq／m3。呼和浩特、包头、集宁、鄂尔多斯四个城市分别有30.0%、44.4%、33.3%、50.0%的工程年平均氧浓度在200Bq／时以上。四个城市氦浓度的普遍水平：包头）鄂尔多斯）集宁）呼和浩特。4、对所有单建式铜室类地下工程和结建式铜室类工程内工作人员所受剂量当量进行了估算。单建式地下工程内工作人员所受剂量当量的范围是1.247mSv-6．SOgmsv，平均值是2.610Sv。结建式地下工程内工作人员所受剂量当量的范围是1．195Sv-8.531mSv，平均值是2.572mSv。两类地下工程内工作人员所受氨照射剂量当量都很高，有一半的工程剂量当量是地面上公众人员剂量当量0.924mSv的两倍以上。5、不管是从浓度角度还是从剂量估算角度分析，地下工程内的氛水平都比较偏高，需要采取一定防护措施，对现有状况进行改善。6、通风是地下工程防治氡污染最简便易行、见效最快的措施。使用防氡涂料是最经济的措施。