Do multiple cycles of aeolian deposit-pedogenesis exist in the reticulate red clay sections in southern China?

Since the Quaternary scientists successfully dis-closed the paleoclimatic significance of the loess-paleo- sol sequence in the Loess Plateau, Northwest China, the loess-paleosol sequence has become well-known terres-trial materials revealing the multiple cyclic changes of Quaternary climates. As a carrier of paleoenvironmental information, it could compare beauty with the deep ocean deposit[8]. In recent years, however, the researchers began to put their sights to southern China. They try t…     

The age of formation of the mirabilite and sand wedges in the Hexi Corridor and their paleoclimatic interpretation

The Hexi Corridor is located at the transition zone of the Asian summer monsoon and westerly airflow, and lies in an important position in terms of its ecological fragility and climatic sensitivity. During a recent field expedition to this region, we found a sedimentary mirabilite layer in a number of localities including Suwushan, Yanchi, Baitujing, Yanchi Gaotai, Huahai, Yumen, Halanuo扙r, and Dunhuang (Fig. 1), which have the potential to provide important information about environmenta…     

Temperature variations on the Tibetan Plateau over the last two millennia

The paleoclimate data recovered from ice cores,tree rings and lake sediments indicate regional features of cfimatic change on the Tibeta n Plateau (TP) during the last 2000 years. The composite temperature reconstructions in-dicate that several main climatic episodes, such as the “LittleIce Age“ between 1400 and 1900, the “Medieval Warm Pe-riod“ in 1150-1400, a less warm period in 800-1100, and an earlier cold period between the 3rd and 5th centuries,occurred in the TP. In addition, temperature varied from region to region. The period from AD 800 to 1100, which waswarm in northeastern TP, was contemporaneous with cool-ing in the western and southern TP. The southern TP ex-perienced warming between 1150 and 1400. For western TP,the δ^18O records of the Guliya ice core indicate that the pe-Hod 1250-1500 witnessed a clear warming. Large-scaletrends in the temperature history from northeastern TP aremore similar to those in eastern China than are the trendsfrom the Guliya ice cap far to the west and southern TP. The most prominent similarities between the temperature varia-tions of the TP and eastern China are such cold phases as 1100-1150, 1500-1550, 1650-1700 and 1800-1850, andthe latter three cold events match with three widespreadg lacial advances which occurred on the TP during the Little Ice A2e.     

Time-division phase modulated single-photon interference in a Sagnac interferometer

We introduce a stable, long-distance singlephoton Sagnac interferometer, which has a balanced configuration to efficiently compensate phase drift caused by change of the fiber-optic path. By using time-division phase modulation, single-photon interference was realized at 1550nm in a 5-km-long as well as 27-km-long Sagnac fiber loops,with a fringe visibility higher than 90% and long-term stability. The stable performance of the single-photon interference indicated that the time-division phase-modulated Sagnac interferometer might readily lead to practical applications in single-photon routing and quantum cryptography.     

谈谈多媒体课件教学的三大误区

在肯定多媒体课件教学在当今现代教育技术中的作用和优势的同时，剖析了现阶段多媒体课件在教学中的应用现状及存在的问题，探讨了如何正确应用多媒体课件教学这一先进教学手段以获得良好的教学效果。     

氧化铝表面有机改性及其在聚苯乙烯中分散性能的研究

为了增强无机化合物氧化铝的亲油性能，采用硅烷偶联剂对氧化铝表面进行预处理，并以本体聚合的方式制备了掺杂氧化铝聚苯乙烯．分别用红外光谱、热重分析和光电子能谱对氧化铝的处理结果进行分析，发现在氧化铝的表面化学吸附了有机层．扫描电镜结果表明经改性的氧化铝在聚苯乙烯中的掺杂量明显增大，分散性更强。     

横泉水库大坝安全自动化观测设计方案初探

针对横泉水库大坝监测点的类型及分布特点，结合大坝安全对监测系统的要求以及当前土石坝监测自动化水平的发展，提出了横泉水库大坝安全自动化观测设计方案，可供有相同或类似该水库大坝安全自动化观测设计参考。     

节水灌溉远程控制系统的结构及其通信设计

搞要：介绍一种以Visual Basic 6．0为开发平台，采用三级结构的计算机远程控制节水灌溉自动控制系统的设计方案．利用计算机，通过通信控制器(现场服务器FCC5000)远程控制灌区阀门，实时采集各种数据，以实现节水灌溉目的.     

基于广域网的金相显微镜远程监控系统

介绍了针对大型金相显微镜设计的远程监控系统。该系统通过广域网传输监控信号，利用微机和单片机实现对金相显微镜的远程监控。同时，提出了动态适应性编码方法，从而很好地协调了传输速度和传输数据量之间的矛盾，实现了视频数据的实时传输。