光学相干层析技术在法庭科学中的新应用

光学影像技术是法庭科学物证检验分析的重要技术手段，具有无损、原位、快速等优势。近年来，随着光学影像技术的不断发展，一些新技术、新方法不断被引入法庭科学领域并付诸应用。光学相干层析技术（简称OCT技术）是一种光学断层成像技术，具有无损、高分辨、快速、断层成像的特点，特别是其可以无损地得到材料或生物组织内部的结构信息，突破了传统二维成像只能进行物质表面分析的局限，因此可成为一种很有前景的新型法庭科学光学影像技术。本文首先介绍了自主搭建的一套三维OCT成像系统，并着重介绍了基于该系统应用于法庭科学油漆物证检验、胶带指纹显现和毛囊特征分析等方面的研究。结果表明，OCT技术非常适合用于法庭科学物证检验分析，作为其他检验的先导技术手段，获取样品内部信息，提取新型光学特征参数。由于其采用光纤化技术，还有望实现便携化、小型化，在现场勘查中开展相关应用。     

基于线阵CCD的二维基准大视场传递方法研究

为实现快速定位定向的要求,利用线阵CCD测量方法,设计了二维基准传递系统,实现北斗定向信息实时传递功能。该系统由北斗定向天线、光源模块和光学测量模块等组成,采用N型目标光源和线阵CCD拼接技术,实现二维基准信息的快速精确传递。利用构建的二维基准传递系统设计精度验证实验,实验结果表明,在测量距离8 m条件下,该系统测角范围为1.5,测量精度在5以内。该方法为实现二维定向基准的大视场传递提供了一种有效的技术解决措施。     

Global well-posedness of the non-isentropic full compressible magnetohydrodynamic equations

In this paper, we are concerned with Cauchy problem for the multi-dimensional (N ≥ 3) non-isentropic full compressible magnetohydrodynamic equations. We prove the existence and uniqueness of a global strong solution to the system for the initial data close to a stable equilibrium state in critical Besov spaces. Our method is mainly based on the uniform estimates in Besov spaces for the proper linearized system with convective terms.     

Surface charge property governing co-transport of illite colloids and Eu(III) in saturated porous media

The transport of colloids and radionuclides is sophisticated because of the variety of charge properties between colloidal particles and host subsurface media, which causes great difficulty in establishing a reliable model of radionuclides migration by taking the colloid phase into consideration. In this work, the co-transport of illite colloids (IC) and Eu(III) in the quartz sand and iron-coated sand porous media was investigated by column experiments to address the predominant mechanism of charge properties on co-transport. Results showed that Eu(III) transport was driven by the illite colloids and electrostatic interaction was critical in governing the co-transport patterns. The promotion of Eu(III) transport by IC was attenuated in the iron-coated sand systems; more IC-Eu(III) complexes were retained uniformly in the column. The pore throat shrinkage caused by electrostatic attachment between aggregated IC and iron oxides exacerbated the physical straining and size exclusion effect of IC-Eu(III) complexes. An aggravated irreversible retention of IC-Eu(III) was detected in iron-coated sand column due to the electrostatic attraction of IC-Eu(III) to host media. The findings are essential for improving the understanding on the potential transport, retention and release risk of colloids associated radionuclides, and imply that the positively charged permeable reactive barrier is an effective strategy to reduce the transport risk of colloid associated radionuclides.     

Stable partial nitritation of mature landfill leachate in a continuous flow bioreactor: Long-term performance,microbial community evolution,and mechanisms

A continuous flow bioreactor was operated for 300 days to investigate partial nitritation (PN) of mature landfill leachate, establishing the long-term performance of the system in terms of the microbial community composition, evolution, and interactions. The stable operation phase (31–300 d) began after a 30 days of start-up period, reaching an average nitrite accumulation ratio (NAR) of 94.43% and a ratio of nitrite nitrogen to ammonia nitrogen (NO₂⁻-N/NH₄⁺-N) of 1.16. Some fulvic-like and humic-like compounds and proteins were effectively degraded in anaerobic and anoxic tanks, which was consistent with the corresponding abundance of methanogens and syntrophic bacteria in the anaerobic tank, and organic matter degrading bacteria in the anoxic tank. The ammonia-oxidizing bacteria (AOB) Nitrosomonas was found to be the key functional bacteria, exhibiting an increase in abundance from 0.27% to 6.38%, due to its collaborative interactions with organic matter degrading bacteria. In-situ inhibition of nitrite-oxidizing bacteria (NOB) was achieved using a combination of free ammonia (FA) and free nitrous acid (FNA), low dissolved oxygen (DO) with fewer bioavailable organics conditions were employed to maintain stable PN and a specific ratio of NO₂⁻-N/NH₄⁺-N, without an adverse impact on AOB. The synergistic relationships between AOB and both denitrifying bacteria and organic matter degrading bacteria, were found to contribute to the enhanced PN performance and microbial community structure stability. These findings provide a theoretical guidance for the effective application of PN-Anammox for mature landfill leachate treatment.     

高效液相色谱法鉴定蓝色圆珠笔油墨字迹的书写时间

由圆珠笔油墨形成的契约、合同、收据和借条等可疑文件的真伪及形成时间的鉴定是目前法庭科学实验室经常遇到的问题, 因此建立一种简便、灵敏和准确的检验圆珠笔油墨字迹色痕的异同及形成时间的方法是十分必要的。文章介绍了一种可以检验圆珠笔油墨的种类及形成时间的方法。这种方法是依据高效液相色谱法分析圆珠笔油墨中染料的种类及染料随时间的变化关系来确定圆珠笔油墨字迹的异同及书写时间,染料随时间的变化可以通过相应的色谱峰的峰面积比计算而得。     

光二极管阵列检测毛细管电泳法分析滚珠水性笔墨水

建立了利用毛细管电泳光二极管阵列检测器连续波长扫描分析滚珠水性笔墨水的方法。首先考查了缓冲溶液的类型、浓度、pH值,以及电泳分离电压对分析结果的影响,同时研究了管径分别为50,75和100 nm的熔融石英毛细管对光二极管阵列检测器检测结果的影响,实验表明毛细管内径的大小与检测器的吸光强度成正比,在保证分离效果的前提下,采用管径为100 nm的毛细管可以提高吸光信号检测强度,因此在紫外和可见光的波长范围内都可以检测到吸收峰。实验确定浓度为20 mmol·L-1 、pH值为8.5的四硼酸钠作为缓冲溶液,熔融石英毛细管从进样口至检测窗口的有效长度为40 cm,内径为100 μm,电泳分离电压为15 kV。利用光二极管阵列检测器在190～600 nm波长范围内进行连续扫描检测,根据三维电泳图中紫外区和可见区电泳吸收峰的特征分析不同种类滚珠水性笔墨水。     

HIV time hierarchy: winning the war while,loosing all the battles

AIDS is the pandemic of our era. A disease that scares us not only because it is fatal but also because its insidious time course makes us all potential carriers long before it hands us our heads in a basket. The strange three stage dynamics of aids is also one of the major puzzles while describing the disease theoretically (Pantaleo et al., N. Engl. J. Med. 328 (1993) 327). Aids starts, like most diseases, in a peak of virus expression [R.M. Zorzenon dos Santos, Immune responses: Getting close to experimental results with cellular automata models, in: D. Stauffer (Ed.), Annual Review of Computational Physics VI, 1999, pp. 159–202; R.M. Zorzenon dos Santos, S.C. Coutinho, On the dynamics of the evolution of HIV infection, cond-mat/0008081], which is practically wiped out by the immune system. However it then remains in the body at a low level of expression until later (some time years later) when there is an outbreak of the disease which terminally cripples the immune system causing death from various common pathogens. In this paper we show, using a microscopic simulation, that the time course of AIDS is determined by the interactions of the virus and the immune cells in the shape space of antigens and that it is the virus's ability to move more rapidly in this space (its high mutability) that causes the time course and eventual “victory” of the disease. These results open the way for further experimental and therapeutic conclusions in the ongoing battle with the HIV epidemic.     

结节性甲状腺肿的傅里叶变换红外光谱体表测定

利用ATR探头和中红外光导纤维红外光谱法在体表测定34个正常甲状腺和20个结节性甲状腺肿的傅里叶变换红外光谱。并比较了二者之间13条谱带的27个指标的差异。结果表明: 结节性甲状腺肿的体表红外光谱中：(1)～2 925 cm-1 谱带(—CH₂的反对称伸缩振动)的峰位, ～1 250 cm-1(PO的伸缩振动)谱带的峰位均明显地向低波数方向移动(P＜0.05);(2)谱带的相对强度(谱峰高度)比值H_{1 740}/H_{1 460}, H_{1 160}/Ｈ_{1 460}和H_{1 160}/H_{1 120} 较正常甲状腺明显降低(P＜0.05);(3)H_{1 080}/H_{1 460}比值明显升高(P=0.008)。这些差异是利用体表红外光谱诊断结节性甲状腺肿的基础。