Acute toxicities of potassium permanganate, formalin, and Lugol’s iodine solution to a marine ciliate, Pleuronema coronatum (ciliophora, scuticociliatida)

Acute toxicities of potassium permanganate, formalin, and Lugol’s iodine solution to a commonly occurred marine ciliate Pleuronema coronatum (Ciliophora, Scuticociliatida) were measured. Linear regression analysis of the results highlighted the close relationships between doses of the medicines and mortalities of the organisms, thus providing a capability to predict toxicity effects from the dose. Toxic effects of the medicines on the ciliates were described in the present paper, and the median lethal concentrations (LC₅₀ values) were given. Results of measurements indicated that 2 h-LC₅₀ and 12 h-LC₅₀ values of formalin on P. coronatum were 59.00×10⁻⁶ and 43.57×10⁻⁶, while those of Lugol’s solutions were 90.13 and 67.84×10⁻⁶ respectively. The tolerance of P. coronatum to formalin is apparently lower than that to Lugol’s iodine solution and potassium permanganate is a suitable medicine to kill ciliates in short time.     

兰州都市圈发展可行性与发展战略研究

近年来都市圈理论的引入和创新发展,对城市化理论有重要影响。我国西部地区的城市化有其特殊性,西部地区的城市化研究对促进西部地区的现代化发展、落实科学发展观、保障全国的可持续发展都具有重要理论与现实意义。都市圈理论对西部地区尤其是西北地区中心城市区域的发展具有指导性,以兰州为例分析了西北地区都市圈建设的可行性与前景。首先分析论证了兰州都市圈建设的可行性,得出了兰州不仅迫切需要建设都市圈而具备发展都市圈的良好条件的结论;接着,以定量与定性结合的方法,评价了兰州在我国西部地区中心城市中的地位和兰州都市圈发展水平,发现兰州都市圈的雏形已经形成,在区域开发中发挥着重要作用;最后,提出了兰州都市圈发展战略,包括战略目标、战略思路、战略重点等,展示了兰州都市圈发展的前景。兰州都市圈可行性的典型研究,也展示了都市圈发展模式在西北地区开发中的应用的可行性,对完善我国的城市化理论和实践具有重要意义。     

井下地震计的P波接收函数正演计算及其稳定性研究——以首都圈地区为例

井下地震计波形记录的P波垂向分量存在频谱极小（spectrum null）现象,导致接收函数的结果不稳定.本文以首都圈地区为例,基于平面波入射的传播矩阵理论,发展了用于计算井下地震计的接收函数正演方法.在此基础上,分析了井下地震计波形垂向分量频谱极小现象,研究其对接收函数稳定性的影响.结果表明,井下地震计波形记录垂向分量的频谱极小开始出现的频率和地震计的埋深相关.该现象可造成反卷积提取的接收函数不稳定,且不稳定情况出现在频谱极小附近的频段,可通过选择合适的高斯因子压制其对接收函数的影响.

     

A dimensional analysis of scaling viscosity and velocity in DEM of constant strain rate tests on asphalt

This paper presents the results from discrete element modelling (DEM) of an idealised (sand) asphalt mixture under constant strain rate (velocity) compressive loading using the Burgers viscoelastic model. Using dimensional analysis it is shown that the effect of scaling applied velocity is the same as that of scaling both viscosities in the Burgers model by the same factor. This has been shown to be the case for a bonded aggregate, and it also has been shown to be applicable even when bond breakage occurs within the sample. This scaling method will be of great benefit in modelling tests on asphalt under different constant strain rates, simply by scaling both viscosities to minimise computational time.     

地下工程震波技术与应用

激发的震波在工程岩土体中传播，检测其波动力学参数，来测试岩土体的工程力学性质。原位震波波速测试技术可以对井巷的岩体模量，支护选型，围岩性质进行检测；利用地震勘探，面波勘探方法可以对矿层厚度，超前探测等方面进行有效检测；震波CT、导波勘探等探测方法对于采面内的地质异常探测有较好的针对性；通过声发射检测技术可以解决地下工程安全问题。实际应用说明，震波探测技术从地下工程的开拓掘进，采场形成到采后管理等过程中有着广泛的应用前景。一些技术已作为地下工程中的日常工作加以应用，但进一步的生产应用还需深入研究。     

CHINA''S REGIONAL DEVELOPMENT IN THE 1980s

l.Introducti0nIntheseveraldecadestilltheendofthe1970s,therewasnoanyleastd0ubtthatChinahadbeenfollOwingabalancedregi0naldevelopmentstrategy.0bligedtotlledolnesticandinternationalsituationofthattime,capitalinvestlnentxvasn1ost1yf0rcedt0beputintotheundevel0pedarea(westeconomiczone),thisstrategyprovedtobelesseffectiveandincurredahugelossofinvestmentbenefit.Althoughthewestzoneisabundantinnatllralresources(mineral,energyresourcesetc.),thelevelofregionaldevel0pmentfromeastzonet0westzoneisgradua1lydec…     

脑囊虫病的CT诊断－附300例分析

作者报告了３００例脑囊虫。对脑囊虫病的ＣＴ表现进行了讨论。作者认为；（１）平扫为多发小囊状低密度灶，如囊壁上有高密度点。（２）较大囊状低密度灶，囊壁上有高密度点。（３）平扫为多发局灶性低密度区，增强出现多发结节及环形强化灶。为诊断脑囊虫病有价值的征象。本文还对脑囊虫病的病理及鉴别诊断进行了讨论。