计算机模拟研究UO2+2在人体细胞液的形态分布

建立了由多种金属离子和小分子配体组成的多相细胞液热力学平衡模型.模拟研究了UO2 2在组织液和细胞液的形态分布及CO2-3、氨三乙酸（NTA）和乙二胺四乙酸（EDTA）浓度对细胞液中UO2 2形态分布的影响.在组织液中,正常生理pH下,当各形态UO2 2总摩尔浓度 [U]= 1.0×10-6 mol/L 或[U]=1.0×10-3 mol/L时,UO2 2均主要以[UO2(CO3)3]4-和[UO2(CO3)2]2-形态存在.在细胞液中,当[U]=1.0×10-6 mol/L时,UO2 2主要以[UO2(CO3)3]4-和[UO2(CO3)2]2-存在；当[U]=1.0×10-3 mol/L,pH为6.0～6.8时,细胞液中存在大量的固相(UO2)3(PO4)2·4H2O,当pH为6.8～7.4时,UO2 2主要以[UO2(CO3)3]4-、[UO2(CO3)2]2-和[(UO2)2CO3(OH)3]-存在.细胞液中(UO2)3(PO4)2·4H2O含量随[U]升高而增加.通过调节细胞液pH和增加细胞液CO2-3浓度均能降低其固相UO2 2配合物含量.在细胞液中增加NTA会增加(UO2)3(PO4)2·4H2O含量,当添加EDTA时会显著降低(UO2)3(PO4)2·4H2O含量.     

单体滑坡灾害风险预测

以重庆市万州区农机技校滑坡为例，讨论了单体滑坡灾害的风险预测方法。提出采用Monte-Carlo方法预测滑坡发生的概率，利用能量守恒原理和谢德格尔公式推算滑程；结合滑坡裂缝的展布方位，预测出滑坡灾害发生后的影响范围；根据承灾体自身特点和相对于滑坡所处的位置，确定出滑坡灾害影响范围内承灾体的易损性；利用GIS对空间数据的图形叠加功能，将滑坡危险性和灾害易损性叠加，并在考虑库区水位动态变化的基础上，动态预测滑坡灾害导致的经济损失，定量预测滑坡灾害风险大小。结果表明，该滑坡在坝前145m水位和50年一遇暴雨工况下可能的经济损失值最大为10260万元；而在滑坡危险性最大的工况下，滑坡灾害风险不一定最大。所得结果可为滑坡灾害防治工程或土地规划立项提供依据，使政府决策部门在防灾减灾工作中更有针对性。     

Canopy Spectra and Remote Sensing of Ashe Juniper and Associated Vegetation

A study was conducted in central Texas to determine the potential of using remote sensing technology to distinguish Ashe juniper (Juniperus ashei Buchholz) infestations on rangelands. Plant canopy reflectance measurements showed that Ashe juniper had lower near-infrared reflectance than other associated woody plant species and lower visible reflectance than mixed herbaceous species in spring and summer. Ashe juniper could be distinguished on color-infrared aerial photographs acquired in March, April, June, and August and on QuickBird false color satellite imagery obtained in June, where it had a distinct dark reddish-brown tonal response. Unsupervised classification techniques were used to classify aerial photographic and satellite imagery of study sites. An accuracy assessment performed on a computer classified map of a photographic image showed that Ashe juniper had producer's and user's accuracies of 100% and 92.9%, respectively, whereas an accuracy assessment performed on a classified map of a satellite image of the same site showed that Ashe juniper had producer's and user's accuracies of 94.1% and 88.1%, respectively. Accuracy assessments performed on classified maps of satellite images of two additional study sites showed that Ashe juniper had producer's and user's accuracies that ranged from 87.1% to 96.4%. These results indicate that both color-infrared photography and false color satellite imagery can be used successfully for distinguishing Ashe juniper infestations.     

长江三峡柑桔的冻害和热害（二）

本文从柑桔冻害和热害的危害因子和指标等级划分的研究和选取入手,着重探讨了长江三峡地区(湖北境内)两害显著的时空变化特征、差异与关联性及对柑桔生产的影响;揭示了80年代以来冬暖春热的重大气候变化是使两害向“两极分化”的根本原因;讨论了三峡水利工程对两害时空格局的可能调整及减灾原理;最后提出了可能的对策。     

Processes involved in uptake and release of nitrogen dioxide from soil and building stones into the atmosphere

Atmospheric NO₂ was taken up by samples of various soils and building stones. The NO₂ uptake rate constants were highest in soil samples taken during the summer months. However, the NO₂ uptake rate constants of the soils and building stones were not significantly correlated with any of the following variables: moisture, pH, ammonium, nitrite, or nitrate. NO₂ uptake by soil and stone was not abolished by autoclaving indicating a chemical uptake process. NO₂ uptake by acidic and air-dry soils and stones resulted in nearly stoichiometric reduction of NO₂ to NO. This reduction was enhanced by the addition of ferrous iron and was further enhanced by incubation under 1 ppmv SO₂. The results suggest that NO₂ reduction may be coupled to oxidation of ferrous to ferric iron which may be reduced again by atmospheric SO₂ thus regenerating the ferrous iron content of the soil or stone. Conversion of NO₂ to NO was not observed in neutral or/and moist soils and stones. NO₂ was also taken up by purified and sterilized quartz sand moistend with water. This uptake was enhanced by addition of humic material but not by addition of bacteria which both had been extracted from genuine soil. Under most conditions, only uptake but no release of NO₂ was observed. However, NO₂ was released in air-dry soils that were heated to 45–65°C, or in ammonium-fertilized soil or stone that was drying up at room temperature. Under the latter conditions mimicking field practice, the NO₂ release reached rates that were similar to the NO release rates.     

沟渠式生物接触氧化法对有机物和氨氮的去除研究

生物接触氧化工艺是目前较为成熟的水质净化技术,国内外在河流水质净化、水体修复中都有较多的研究和应用.在实验室采用沟渠式生物接触氧化组合系统处理模拟村庄面源污水,较好地去除了有机物并实现氨氮转化.结果表明,当进水COD为130～290mg/L、氨氮为30～40mg/L、水力负荷为0.19～0.24m3/(m2·d)的条件下,该系统稳定运行11周,COD和氨氮的平均去除率分别达85%和79%.     

Fe0/厌氧微生物联合体系处理2,4,6-三氯酚影响因素的研究

利用Fe⁰/厌氧微生物联合体系对2,4,6-三氯酚(2,4,6-TCP)进行降解研究。结果表明，Fe0/厌氧微生物联合体系可以有效降解2,4,6-TCP，Fe⁰与厌氧微生物之间存在明显的协同效应。Fe⁰/厌氧微生物联合体系处理2,4,6-TCP的最优条件为：微生物接种量0.434 g VSS/L，Fe⁰投加量15 g/L，体系初始pH值7.0～8.0。     

可持续旅游及其区域实现途径探讨—以井冈山风景名胜区为例

可持续旅游是 80年代中期以后提出的关于旅游业发展的新思想。经过十多年的不断拓展深化 ,已经得到世界各国的广泛认同 ,并作为跨世纪旅游业发展的战略指导思想。本文从可持续旅游的由来和对可持续旅游内涵实质的界定角度出发 ,结合可持续旅游实现途径的探讨 ,以井冈山风景名胜区为例 ,对风景区旅游业可持续发展进行了深入的探讨 ,为景区的发展规划提出了战略性构想 ,以期能对井冈山风景名胜区旅游资源的可持续利用和旅游业的可持续发展起到抛砖引玉的作用     

企业需要建立人性化的安全管理

由于我国对企业特别是海外来大陆投资的企业，缺乏严格的安全管理手段，致使不少企业屡次出现安全事故。为了减少企业安全事故的发生，提高企业安全度，要求企业在贯彻“安全第一，预防为主”的基本方针的基础上。建立“以人为本。以制度和伦理道德为约束的人性化的安全管理系统”。本文给出了该系统的模型，并对此模型进行了分析和解释，探讨了相关的几个理论基础，最后给出了人性化安全管理的实质。通过该系统的管理执行，使企业在尊重人权、尊重生命的前提下发展壮大，最终实现安全的全球化。