气相色谱-串联质谱法同时测定卷烟滤嘴中15种多环芳烃

建立了气相色谱-串联质谱同时检测卷烟滤嘴中15种多环芳烃的方法。卷烟滤嘴用二氯甲烷振荡萃取后,经0.22μm有机相滤膜过滤,采用DB-5MS色谱柱(30 m×0.25 mm,0.25μm)进行分离,电子轰击源、正离子模式下以多反应监测模式进行检测,内标法进行定量。15种多环芳烃(苊烯、苊、芴、菲、蒽、荧蒽、芘、苯并[a]蒽、屈、苯并[b]荧蒽、苯并[k]荧蒽、苯并[a]芘、二苯并[a,h]蒽、苯并[g,h,i]苝和茚并[1,2,3-c,d]芘)的线性关系良好,相关系数(R~2)为0.991 4~0.999 9。15种多环芳烃在低、中、高3个添加水平下的平均回收率为81.6%~111.2%;除了芴在低添加水平时相对标准偏差为19.2%外,其他相对标准偏差均小于16%。15种多环芳烃的检出限为0.02~0.24 ng/滤嘴,定量限为0.04~0.80 ng/滤嘴。方法前处理简便,具有快速、准确、灵敏度高及重复性好的优点,适用于卷烟滤嘴中多环芳烃的分析。     

一种基于仿真资源包的虚拟教学训练系统设计与实现

国防现代化的加速发展对人才培养提出了更高的要求;为了更便捷、更高效的培训部队人才,用最低的消耗实现最佳的训练效果,提出了一种基于仿真资源包的虚拟教学训练系统设计与实现方法;支持仿真资源包的自定义扩展,采用资源包加运行平台的技术架构,满足了结构原理、岗位操作、维护保养、故障排除等方面的训练需求,构建了集教、学、训、考等功能于一体的虚拟教学训练系统;最后应用实例表明,该系统可有效满足教学需求,节省教学资源,提高教学效率,取得了良好的应用效果。     

Analysis of radiation environmental safety for China＇s Spallation Neutron Source （CSNS）

The China Spallation Neutron Source（CSNS） is going to be located in Dalang Town,Dongguan City in the Guangdong Province.In this paper we report the results of the parameters related with environment safety based on experiential calculations and Monte Carlo simulations.The main project of the accelerator is an under ground construction.On top there is a 0.5 m concrete and 5.0 m soil covering for shielding,which can reduce the dose out of the tunnel＇s top down to 0.2 μSv/h.For the residents on the boundary of the CSNS,the dose produced by skyshine,which is caused by the penetrated radiation leaking from the top of the accelerator,is no more than 0.68 μSv/a.When CSNS is operating normally,the maximal annual effective dose due to the emission of gas from the tunnel is 2.40×10-3 mSv/a to the public adult,and 2.29×10-3 mSv/a to a child,both values are two orders of magnitude less than the limiting value for control and management.CSNS may give rise to an activation of the soil and groundwater in the nearest tunnels,where the main productions are 3H,7Be,22Na,54Mn,etc.But the specific activity is less than the exempt specific activity in the national standard GB13376-92.So it is safe to say that the environmental impact caused by the activation of soil and groundwater is insignificant.To sum up,for CSNS,as a powerful neutron source device,driven by a highenergy high-current proton accelerator,a lot of potential factors affecting the environment exist.However,as long as effective shieldings for protection are adopted and strict rules are drafted,the environmental impact can be kept under control within the limits of the national standard.     

Brownian localization： A generalized coupling model yielding a nonergodic Langevin equation description

A minimal system-plus-reservoir model yielding a nonergodic Langevin equation is proposed, which originates from the cubic-spectral density of environmental oscillators and momentum-dependent coupling. This model allows ballistic diffusion and classical localization simultaneously, in which the fluctuation-dissipation relation is still satisfied but the Khinchin theorem is broken. The asymptotical equilibrium for a nonergodic system requires the initial thermal equilibrium, however, when the system starts from nonthermal conditions, it does not approach the equilibration even though a nonlinear potential is used to bound the particle, this can be confirmed by the zerotb law of thermodynamics. In the dynamics of Brownian localization, due to the memory damping function inducing a constant term, our results show that the stationary distribution of the system depends on its initial preparation of coordinate rather than momentum. The coupled oscillator chain with a fixed end boundary acts as a heat bath, which has long been used in studies of collinear atom/solid-surface scattering and lattice vibration, we investigate this problem from the viewpoint of nonergodicity.     

荧光粉Ba5-3x/2B4O11∶xEu3+的制备及发光性能

采用高温固相烧结法成功制备了Ba_5-3x/2B₄O₁₁∶xEu³⁺(x=0.02~0.22)荧光粉,利用XRD和SEM等对荧光粉进行了结构和形貌表征。 在激发波长为393 nm的条件下,发射峰(596、621、657和706 nm)与Eu³⁺的⁵D₀-⁷F_J(J=1,2,3,4)电子跃迁相对应,其中621 nm最强发射峰由Eu³⁺离子⁵D₀→⁷F₂电偶极跃迁造成。 文章还研究了Eu³⁺掺杂浓度对Ba_5-3x/2B₄O₁₁∶xEu³⁺发光性能的影响,结果表明,荧光粉的发光强度随着Eu³⁺掺杂量的增加呈现先增大后减小的趋势,Eu³⁺最佳掺杂量为0.16。     

悬浮固化分散液液微萃取技术的发展及应用进展

综述了悬浮固化分散液液微萃取技术的发展,及其在水、食品和生物样品分析中的应用进展,并对其前景作了简要展望(引用文献67篇)。     

Silicon-based optoelectronic heterogeneous integration for optical interconnection

The performance of optical interconnection has improved dramatically in recent years. Silicon-based optoelectronic heterogeneous integration is the key enabler to achieve high performance optical interconnection, which not only provides the optical gain which is absent from native Si substrates and enables complete photonic functionalities on chip, but also improves the system performance through advanced heterogeneous integrated packaging. This paper reviews recent progress of silicon-based opt...     

Piranha化学法与化学浴沉积制备Sb2S3薄膜

采用Piranha化学法与化学浴沉积技术相结合,在玻璃基板上成功制备了Sb2S3薄膜.研究了Piranha溶液不同处理时间对基板表面润湿性的影响,同时研究了Sb2S3薄膜相组成及形貌.结果表明,Piranha溶液能够有效地改善玻璃基板表面的润湿性,当处理时间为25 min时,基板表面润湿角达到最低值12.83°.Piranha溶液处理后的基板对于Sb2S3薄膜的沉积具有积极的诱导作用.沉积得到薄膜经200℃煅烧1h,由非晶态转变为正交相,薄膜在基板表面以单层球形颗粒平铺堆积生长.     

pH值对水热合成BiVO4粉体及其光催化性能的影响

以五水硝酸铋和偏钒酸铵为起始原料,在不同前驱液pH值(0.5、5、7、9、11)条件下水热合成制备BiVO4粉体,采用X射线衍射仪(XRD)和扫描电子显微镜(SEM)表征其晶相结构和微观形貌,以罗丹明B(RhB)为目标降解物研究BiVO4粉体紫外光催化性能,研究结果表明:水热合成的BiVO4粉体均为单斜相,且结晶良好,纯度较高;粉体具有四种微观形貌,分别为表面光滑致密的多面体、不规则棒状、细微树枝状、长径比稍小的长方柱状;pH =7合成的细微树枝状BiVO4粉体,紫外光照射30 min RhB降解率达到90;,照射120 min降解率达到98;以上.     

电感耦合等离子体质谱、中子活化分析及其它谱学方法测定环境、生物样品中铝形态和含量研究进展

本文综述了上世纪90年代以来电感耦合高频等离子体质谱(ICP-MS)、中子活化分析(NAA)以及其它谱学方法测定环境生物样品中铝形态的研究进展,共引用文献60篇。