自模板法制备介孔空心无机微/纳米结构

与传统的软、 硬模板法相比, 近期发展的自模板法具有反应步骤少和无需额外模板等众多优点, 同时, 介孔空心无机微/纳米结构在催化、 能源和医药等领域的巨大应用前景也使其制备方法备受关注. 本文根据不同的反应机理, 从Ostwald熟化、 表面保护刻蚀、 柯肯达尔效应和电偶置换反应4个方面分别综述了自模板法的最新研究进展和应用现状, 并展望了自模板法的研究与应用前景.     

无衰变二能级原子在电磁场中态的演化

求解了经典电磁场中二能级原子系统的密度矩阵演化方程 。     

靛酚蓝显色法直接测定血浆氨

建立了血浆氨的靛酚蓝直接显色测定新方法,研究了介质酸度、显色时间、共存物质及抗凝剂等的影响。结果表明,以柠檬酸钠作抗凝剂,在pH 10.5～11.2的磷酸盐缓冲体系中显色强度高,干扰小。有色化合物最大吸收波长位于630 nm,表观摩尔吸光系数为2.48×104 L·mol-1·cm-1。血浆氨浓度在0～1 500 μmol·L-1范围线性关系良好(r=0.999 9),检测下限为1.7 μmol·L-1,相对标准偏差RSD为1.13%(n=11),回收率为93.6%～101.6%,平均回收率97.0％。用本法测定43例正常人和97例各型肝病患者血浆氨含量均获得满意结果。     

热中子分析探雷的中子源慢化装置设计与优化

与传统的地雷探测技术相比,热中子分析(Thermal Neutron Analysis,简称TNA) 探雷技术具有准确率高、虚警率低和对环境适应性强的特点,但探测速度较慢,制约了其广泛应用。为了提高地雷位置处的慢热中子通量,缩短探测时间,提出了一种基于252Cf 的中子源慢化装置设计构型,主要包含中子慢化层、中子反射层、本底 屏蔽层和侧向中子吸收层4 个部分。采用数值模拟的方法比较了4种常用中子慢化(反射) 材料的性能,优选高密度聚乙烯作为慢化材料,石墨作为反射材料。同时,为了满足辐射安全要求,对屏蔽材料的结构进行了优化计算。按照设计构型搭建了TNA 探雷实验平台。在104 n/s 中子源强下优化了慢化层和反射层的厚度,测试了装置慢化效能,在107 n/s 中子源强下评估了装置辐射安全性能。结果表明,采用该装置可使地雷位置处的慢热中子通量提升11 倍以上,并能有效保障辐射安全。Compared with the traditional landmine detection methods, Thermal Neutron Analysis (TNA) landmine detection has the advantages of high accuracy, low false alarm rate and strong adaptability to the environmental change.But the long detection time restrict the wide application of this technology. In order to shorten the detection time, one possible design of neutron moderation device based on 252Cf neutron source is proposed to enhance the moderated neutronflux in mine position. The device consists of four parts, the neutron moderator, the neutron reflector, the background shield and the useless neutron absorbing layer. Then, the performance of four widely used materials in neutronics was compared with MCNP5 code, and HDPE was chosen as the neutron moderator material, graphite as the neutron reflector material. The thickness of the useless neutron absorbing layer was optimized at the same time. Finally, an experimental platform of 252Cf neutron moderation device was assembled on the basis of simulation results, and a series of experiments were carried out to optimize the geometric dimensions and evaluate the dose equivalent with two different strengths neutron source, 104 and 107 n/s. The results indicate that this device can effectively enhance the thermal neutron flux at mine position by more than 11 times and ensure the radiation safety.     

Template identification technology of nuclear warheads and components

Template identification technology （TIT） is designed for the scenarios where a batch of disarmed nuclear weapons or components would be dismantled to observe a nuclear disarmament treaty. The core function played by the TIT is to make a judgment on whether the verified item belongs to a certain kind of nuclear weapons or component （NW/NC） or to which kind the verified item belongs. This paper analyses the functions played by the TIT in the process of NW/NC dismantlement, and proposes that two phases would be followed when applying the TIT： firstly to establish NW/NC templates with a sample of size n drawn from a certain kind of disarmament NW; secondly to authenticate NW/NC by means of the TIT. This paper also expatiates some terms related to the concept of the TIT and investigates on the development status of NW/NC TIT based on radiation signatures. The study concludes that the design of template structure is crucial to the establishment of an effective TIT and that starting from different research angles and aiming at the same goal of classification different template structures and corresponding template identification methods can be built up to meet specific identification requirements.     

模板识别技术在核弹头及其核部件销毁过程中的应用场景和作用

模板识别技术是认证核弹头及其核部件的一项关键技术。模板识别技术是指利用真实核弹头及其核部件的测量数据建立相应的模板，然后利用这些模板，通过特定的比较算法，判断核查对象的类别。图1是模板识别技术在核弹头及其核部件销毁过程中的应用场景假设，虚线表示模板建立的流程，实线表示模板应用的流程。     

无衰变二能级原子在电磁场中态的演化

求解了经典电磁场中二能级原子系统的密度矩阵演化方程 ,得到了系统状态的演化规律。     

密封容器中钚材料同位素丰度和年龄的测量

根据相对效率法的原理，利用PC/FRAM分析软件，开展了用高分辨γ谱仪测量密封容器中钚材料的同位素丰度和年龄的实验研究.研究结果表明，同位素丰度和年龄的分析精度随能谱测量精度的提高而提高，如果能谱的测量精度不够，通过PC/FRAM分析得出的钚材料的同位素丰度和年龄有偏低的可能.因此，在能谱测量过程中，建议通过监测某个特征峰的峰面积计数来判定239Pu丰度和年龄的测量精度是否已满足测量要求.Based on the concept of relative detection efficiency, some experiments have been conducted to measure the isotopic abundance and the age of the plutonium material in a sealed container by a high-resolution γ-ray spectrometer. The PC/FRAM software analyzes the spectra. The study shows that the analysis precision of the isotopic abundance and the age will rise as the spectral measurement precision increases, and that If the spectral measurement precision is not enough, the analyzed results by the PC/FRAM software might be lower. Hence, the study suggests that a spectral peak is monitored to show lights on the spectral measurement precision during the process of spectrum acquirement.     

钚部件属性γ射线综合测量原型系统

通过γ射线辐射探测、能谱分析和信息屏障等技术集成，建立了一套可用于核裁军核查的钚部件的钚存在、武器级钚和年龄属性的HAM-1型γ射线综合测量系统.在不泄漏核部件敏感设计信息的前提下，探测核部件是研制HAM-1型γ射线综合测量系统的基本出发点.根据信息屏障的设计要求，选用ARM微处理器作HAM-1的控制中心，自行研发了高分辨γ能谱的解谱分析技术和属性分析技术，编制了HAM-1型γ射线综合测量系统的应用软件，实现了能谱采集、数据分析、结果显示的自动化和核部件敏感设计信息的保护. 关键词： 钚部件 属性测量 信息屏障 γ射线综合测量系统     

逆向案例教学法在普通化学教学中的应用及体会

分析了普通化学课程目前在教学环节所存在的问题,并针对这些问题提出了逆向案例教学法的改革举措。