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.     

简析《说文解字》中部分饮食文字的背景

本文选择了《说文解字》中与饮食有关的一部分字，把它们分为粮食、蔬菜、肉食、酒水4大类。根据字形与字义的关系，分析了当时社会的饮食文化背景，揭示了社会发展与文字发展的关系。     

有交流的博弈及其特点

从有交流的策略形式的博奕(strategic-form game)和有交流的贝叶斯博奕(Bayesian game)两个方面介绍了引入有交流的博奕(Game With Communication)的概念能极大地简化博奕模型，而且能够得出更易于分析的均衡解，并指出了有交流的博奕的概念在经济活动中设计激励相容的协调机制中的重要应用价值。     

太阳能集热铜片与铜管的超声波缝焊技术

研究了太阳能集热铜片和铜管的超声波缝焊机理，认为焊缝是由焊接界面金属原子之间的相互扩散，接触峰点之间的相互熔焊及焊缝界面金属之间的机械嵌合共同作用形成的，同时对焊接过程中材料硬度及焊接参数对拉伸强度的影响进行了试验研究。     

汽车悬架振动分析研究方法

提出了一种评价悬架振性能的分析方法，根据汽车振动特点建立八自由度振动模型，以隆格－库塔法为算法基础，运用计算机进行数值求解，计算出振动模型在运动过程中受到激励时的振动位移，速度和加速度值以及车轮相对动载与加速度有效值等评价指标。并对ＳＡＮＴＡＮＡ２０００车型进行了初步振动分析。     

基于PROLOG元级扩充的知识消化系统

通过对ＴＵＲＢＯ ＰＲＯＬＯＧ进行元级扩充，实现了一个能在知识获取时对新知识进行逻辑一致性检测的实用知识消化系统，所采用的技术和方法对提高微机ＰＲＯＬＯＧ知识库系统的质量和性能有重要参考价值。     

C／Cu复合材料的热膨胀性能及合金元素的影响

研究了３００Ｋ－１０７３Ｋ温度范围内两种纤维比Ｃ／Ｃｕ复合材料的热膨胀性能及合金元素的影响。结果表明，在α－Ｔ曲线的水平和下降阶段，合金元素对Ｃ／Ｃｕ复合材料热膨胀性能的影响主要取决于合金元素对其界面结合强度的影响程度。