亚硝酸型SND工艺中DO的选择

为了准确、快捷地选定亚硝酸型同时硝化／反硝化生物脱氮工艺(简称亚硝酸型SND工艺)的最适宜溶解氧浓度(DO)并优化该工艺的控制过程，探讨了最佳DO的影响因素及操作过程中DO的选择方法。由于氨氮浓度、有机物浓度、氧传质阻力和构筑物类型等许多操作条件对DO的影响非常复杂，对其研究还不广泛和深入，目前DO的选择一般参照经验值或通过现场试验研究来确定。     

FISH技术在污水生物除磷脱氮研究中的应用

在简单介绍荧光原位杂交(FISH)的基本原理后,着重讨论了该技术在污水生物除磷、脱氮工艺中的应用现状、特点和前景。尽管污水生物除磷、脱氮工艺的宏观性能与微生物相的关系密切,但因缺乏适宜的检测技术,对工艺系统中微生物类型、数量和结构等了解还很不充分。研究表明：FISH技术能够为除磷菌、硝化菌的识别与再分类提供优越的检测手段;与聚合酶链反应(PCR)等其它技术相结合,可使FISH技术更具生命力。     

The Distortion of Energy Deposit Distribution of (12)～C Ions in Water

The transport process of 12C ions in water was studied with SRIM code and Geant4 toolkit.The SRIM results indicate that the transverse diffusion of 12C ion beam causes distortion of energy deposit along the beam direction.The distortion becomes more notable as the trans-verse diffusion increases.The simulation results of Geant4 indicate that the influence of secondary fragments on energy deposit distribution would be the main factor causing the distortion in higher energy range.In the region adjacent to the beam line where the contribution from 12C ions domi-nates,the contributions from secondary fragments are ignorable.The further from the beam axis the region locates,the larger the contributions from secondary fragments,until the contributions from secondary fragments are ignorable.The further from the beam axis the region locates,the larger the contributions from secondary fragments,until the contributions from secondary frag-ments exceed that of 12C.Among all the secondary fragments,the contributions of H,He and B ions are mostly notable.It is also found that some positron-emitting secondary fragments could be very useful for position emitting tomography (PET).     

探求国际／区域分销商未来发展趋势

国际和区域分销商通过自己的实力和贴心的服务获得了制造商的认可。随着分销市场竞争日益加剧,他们必须不断寻找维持长久竞争优势的妙方。与大陆本地元器件分销商相比,国际和区域分销商的最大优势在于其广泛的国际知名品牌代理线资源和全球或区域网络的运作     

基于双吸收结构的谐振腔增强型光探测器

为了实现对传统谐振腔增强型（RCE）光探测器的优化,提出了一种具有双吸收结构的RCE光探测器。首先从理论上分析了它的量子效率和高速响应特性,然后将其与传统的RCE光探测器进行了比较。结果表明,双吸收结构RCE光探测器在保持高速响应特性的基础上,其量子效率较传统RCE光探测器得到了进一步提高。实验上成功制备了双吸收结构的...