第四次数学危机

以清晰集理论为基础,阐明了模糊集合中的相等、包含、并、交等运算的不完备性(即词不达意)和产生的原因,进而阐明模糊集中的排中律(互补律)不成立,是个错误的结论。     

利比亚拜尼·沃利德给水工程规划

论述了利比亚拜尼·沃利德地区供水系统的基本特征、存在的主要问题以及解决措施.针对该沙漠地区供电、供水不连续,用水时间较为集中的实际情况,选择水塔供水代替常规的泵房直供,并且采用沙漠来水及地下水多水源供水以提高供水保障率.供水区域划分充分考虑了原有水池、水塔、水井等构筑物的利用,以减少工程投资.     

IEEE 802.11a DCF协议吞吐量与时延性能分析

为了准确评估IEEE 80211a系统性能,指导同层规划工作,提出了改进二维Markov模型. 从成帧效率和分布式协调功能（DCF）协议效率2个方面对IEEE 802.11a 无线局域网（WLAN）的性能进行分析,得出饱和条件下系统归一化吞吐率和平均分组时延,并以此为基础,给出了不同节点数条件下,基本接入模式和请求发送/确认发送（RTS/CTS）模式切换门限值,使网络性能达到最优.     

华能巢湖电厂水处理系统优化设计

在华能巢湖电厂一期工程水处理系统设计中,遵循着精简系统、布置紧凑、重视环境效益的设计优化理念,对水处理系统工艺和布置进行了优化设计,使整个系统的投资、布置占地、性能等指标突出,取得了良好的技术经济效果。     

槲皮素-3-O-乙酸乙酯的合成及清除自由基活性研究

以芦丁为原料,利用苄基选择性保护羟基,脱去芦丁糖,再经Williamson反应及脱苄基,合成了标题化合物,总收率63.8%。其结构经IR、~1HNMR、~(13)CNMR及MS进行了表征。分别采用邻二氮菲法和DPPH法测定了标题化合物对羟基自由基和DPPH自由基的清除作用。结果显示,标题化合物较槲皮素具有更强的清除羟基自由基及DPPH自由基活性。     

Energy analysis of stability of twin shallow tunnels based on nonlinear failure criterion

Based on nonlinear Mohr-Coulomb failure criterion, the analytical solutions of stability number and supporting force on twin shallow tunnels were derived using upper bound theorem of limit analysis. The optimized solutions were obtained by the technique of sequential quadratic programming. When nonlinear coefficient equals 1 and internal friction angle equals 0, the nonlinear Mohr-Coulomb failure criterion degenerates into linear failure criterion. The calculated results of stability number in this work were compared with previous results, and the agreement verifies the effectiveness of the present method. Under the condition of nonlinear Mohr-Coulomb failure criterion, the results show that the supporting force on twin shallow tunnels obviously increases when the nonlinear coefficient, burial depth, ground load or pore water pressure coefficients increase. When the clear distance is 0.5to 1.0 times the diameter of tunnel, the supporting force of twin shallow tunnels reaches its maximum value, which means that the tunnels are the easiest to collapse. While the clear distance increases to 3.5 times the diameter of tunnel, the calculation for twin shallow tunnels can be carried out by the method for independent single shallow tunnel. Therefore, 3.5 times the diameter of tunnel serves as a critical value to determine whether twin shallow tunnels influence each other. In designing twin shallow tunnels,appropriate clear distance value must be selected according to its change rules and actual topographic conditions, meanwhile, the influences of nonlinear failure criterion of soil materials and pore water must be completely considered. During the excavation process, supporting system should be intensified at the positions of larger burial depth or ground load to avoid collapses.     

黄河三门峡库区泥沙对COD的影响研究

为了研究黄河三门峡库区泥沙对化学需氧量（COD）的影响,在三门峡坝下、潼关和龙门3个断面取样,并按要求分别配制成清水、清浑水、浑水水样,测定相同水体加酸保存,相同水样的清浑水和清水,含沙量大于3kg/m3的清水、清浑水、浑水等水样的COD值。得出结论为：（1）三门峡库区黄河支流和枯水季节的干流,用CODcr测定能反映水体有机污染程度;（2）对于沙量大于3kg/m3的水体,清水CODcr浓度比较能够有代表性地反映水质有机污染状况。     

电石法PVC清洁生产总结

总结了电石法PVC清洁生产示范试点工作,介绍了包括电石渣清液回用、乙炔水环泵冷却水循环利用、水洗塔下水循环利用及PVC分馏尾气等项目的工艺流程及实施情况和效果。     

洁净煤技术发展概况

煤炭是世界一次能源的重要组成部分,煤炭占世界能源的首位。但是煤炭又是不洁净的能源。它在为社会做出具大贡献的同时,在其开采、加工、储运和使用过程中,也产生一系列环境污染问题。必须提高煤炭的利用率,减少燃煤对大气的污染,发展洁净煤技术,以解决中国煤炭在开发利用中效率低和污染严重的问题。     

Optical properties and adhesion performance of optically clear acrylic pressure sensitive adhesives using chelate metal acetylacetonate

Optically clear acrylic pressure-sensitive adhesives (PSAs) with different co-monomers were synthesized. This study employed metal chelate aluminum acetylacetonate and zirconium acetylacetonate as curing agents. The optical properties of the acrylic PSAs were examined by UV–visible spectroscopy and a prism coupler. In addition, the adhesion performance was obtained by assessing the peel strength, the tack, and the shear adhesion failure temperature. The decrease in the adhesion performance may be related to a higher crosslinking density, which also resulted in a higher gel content.