超临界萃取技术在生物资源开发和有机废水处理中的应用研究

超临界萃取技术在生物资源开发和有机废水处理中的应用研究＠刘华￥中国科学院地球化学研究所超临界ＣＯ＿２萃取,有机废水处理,珊瑚姜油,辣椒色素超临界萃取技术在生物资源开发和有机废水处理中的应用研究刘华（中国科学院地球化学研究所,贵阳５５０００２）收稿日期：１９...     

Flow of groundwater with variable density and viscosity, Atikokan Research Area, Canada

 Flow of groundwater with variable density and viscosity was simulated at the Atikokan Research Area (ARA) in northwestern Ontario, Canada. An empirical viscosity–concentration equation was modified to include total-dissolved-solids (TDS) data from the ARA. The resulting equation was used successfully to estimate reasonably accurate viscosity values over the expected range of temperature and concentration, in comparison with experimental values derived for sodium chloride solutions. A three-dimensional finite-element code, MOTIF, developed by Atomic Energy of Canada Limited, was used in the simulations. The inclusion of the effects of depth-increasing temperature and TDS-dependent fluid-density distribution, while maintaining only a temperature-dependent viscosity relationship in a simulation, resulted in a more penetrative flow against expected buoyancy effects (i.e., the physics of the system was not honored). Accounting for concentration in the viscosity equation caused water to be less penetrative and more in accordance with the expected physics of the system. A conclusion is that fluid concentration should be considered simultaneously in calculating the density and viscosity of a fluid during modeling of variable-density flow in areas underlain by fluids with high TDS. Results of simulations suggest that both flow directions and magnitudes should be employed simultaneously during the calibration of a model. Large-scale groundwater movement in the ARA may be analyzed with carefully selected vertical no-flow boundaries. By incorporating the geothermal temperature gradient, groundwater recharge increases by 12%; thus, this gradient plays a significant role in groundwater flow at the ARA. Variability in the fluid concentration at the ARA neither decreases nor increases recharge into the groundwater system. The hypothesis that an isolated continuous regional flow system may exist at depth in the ARA is not supported by these simulations. Received, September 1996 Revised, September 1997, February 1998 Accepted, February 1998     

环境污染及保护对策

环境保护中一个非常重要的工作,是广泛深入地开展环境地质工作。在赣南、江西乃至全国,环境地质工作的主要内容是防治水土流失,严禁废渣、废水随意排放,控制人口激增,保护有限耕地;为保护生态平衡,必须加强环境立法与执法,提高环境保护的重要性和必要性的认识,大规模切实地保护耕地,因地制宜植树造林。     

A coupled model for prediction of settlement and gas flow in MSW landfills

Prediction of long‐term settlement and control of gas pollution to the environment are two principle concerns during the management of municipal solid waste (MSW) landfills. The behavior of settlement and gas flow in MSW landfills is complicated due to the combined effect of mechanical deformation of the solid skeleton and continuous biodegradation of the waste. A one‐dimensional settlement and gas flow model is presented in this paper, which is capable of predicting time evolution of settlement as well as temporal and spatial distribution of gas pressure within multi‐layered landfills under a variety of operating scenarios. The analytical solution to the novel model is evaluated with numerical simulation and field measurements. The resulting efficiency and accuracy highlight the capability of the proposed model to reproduce the settlement behavior and gas flow in MSW landfills. The influences of operating conditions and waste properties on settlement and gas pressure are examined for typical MSW landfills. Copyright © 2009 John Wiley & Sons, Ltd.     

闪电和固、液态降水关系差异的数值模拟

为了进一步认识闪电和固、液态降水的关系,本文利用三维雷暴云动力-电耦合数值模式,通过设置敏感性试验组,模拟了一次雷暴过程,分析雷暴中闪电和降水的特征,以及闪电和固、液态降水对垂直风速的依赖关系,探讨闪电与固、液态降水的时空分布关系和单次闪电表征的降水量(RPF:rainyields per flash)。结果表明:对流云降水中,液态降水占主要部分,但固态降水比液态降水对于垂直风速的依赖性更强。随着对流的增强,固态降水在总降水中占的比重越来越大。首次放电时间不断提前,闪电峰值落后垂直风速峰值,总闪数一开始随对流的增强而增加,对流一旦增强到一定程度,总闪数则逐渐减小。固态降水和液态降水的开始时间和峰值时间均随着对流的增强而不断提前,而液态降水出现时间和峰值时间均提前于固态降水。雷暴云首次放电的时间滞后于液态降水,而闪电峰值提前固态降水峰值或与固态降水峰值同时产生。雷暴云中的放电活动集中在强降水区域前缘的较弱降水区,强降水区对应的闪电较少,对流的增强会使降水区域面积、降水量和降水强度增加。由于液态降水总量远大于固态降水总量,固、液态RPF的数值相差达到一个量级,但单位时间内固态降水和液态降水增加的速率相近。在单位时间内闪电次数越多,RPF则越小,而固态RPF和闪电次数的线性相关性明显好于液态RPF,所以利用固态降水可以更好地预报闪电。这些结果有助于进一步认识闪电和降水的关系,并可为闪电预报提供新的思路。     

Quantitative assessment of dissolved radiotracers in the English Channel: Sources, average impact of la Hague reprocessing plant and conservative behaviour (1983, 1986, 1988, 1994)

Knowledge of long-term movements of water-masses in the English Channel has been substantially improved using hydrodynamic modelling coupled with radio-tracers studies; nevertheless, the precision of results so obtained is still largely dependent on measurement precision. New tools are now available to make more accurate determinations of radio-tracer distribution: (1) Repositioning of station locations at the same tide reference-time, giving a homogeneous spatial data set, coupled with the possibility of interpolating and quantifying the amounts of dissolved radioactivity flowing through the English Channel; (2) the first measurements of tritium (³H) in seawater on a large scale in the English Channel demonstrate that this fully conservative radionuclide is a clearly identifiable marker of industrial releases; (3) recent campaigns carried out during the FLUXMANCHE II CCE (1994) programme show the general distribution of dissolved radionuclides ¹³⁷Cs, ¹³⁴Cs, ⁶⁰Co, ¹²⁵Sb, ¹⁰⁶Ru and ³H in the English Channel and the Irish Sea; and (4) the re-utilisation of data from previous campaigns (1983, 1986, 1988) provides indications, at any given location in the English Channel, about the average dilution and distribution of releases derived from the La Hague reprocessing plant. Excesses and losses of radionuclides are now quantified with respect to known source terms; estimates of losses are provided for non-conservative radionuclides, while an excess of ¹³⁷Cs was observed in the English Channel during the period 1983–1994. This excess, which has the same order of magnitude as the quantities released from La Hague plant in the English Channel, could be explained by about 1% of the Sellafield reprocessing plant releases entering the Channel. These results confirm and give a more detailed picture of the previously known distribution of water masses in the English Channel. They lead to clear information about transit times and dilution at this scale, and provide directly comparable data for the validation of hydrodynamic models.     

我国高放废物处置库的选址与能动断层研究

随着我国核电工业建设步伐的加快,高放废物处置库的场址选择成为当前极为紧迫的课题。本文分析了甘肃北山高放废物处置库的选址现状,提出应加快相关核安全法规的建设以指导场址的选择;应对北山地区补充地震地质调查工作,特别是对区内的几条断层要进行断层能动性的研究。这对场址的适宜性是一个带有颠覆性的问题。     

排土场滑坡与泥石流灾害控制技术与方法

对排土场滑坡破坏模式进行了FLAC3D模拟分析。结合具体工程实例,分析形成潜在滑坡、泥石流灾害的原因。针对排土场灾害,强调以防为主,防治结合的思想。提出以逆序排土工艺及倾斜分层排土工艺进行排土,提高排土场自身稳定;结合坡面疏导排水、底部泄流体等综合技术,对排土场灾害进行防治。对排土场灾害的预防与治理有一定的借鉴意义。     

黄山风景区旅游废弃物生态足迹历时性分析

历时性旅游废弃物演化规律及生态影响研究是制定旅游地可持续发展战略的基础性工作。以生态足迹理论为基础,利用1979—2018年相关统计资料与团队实地调研数据,对黄山风景区旅游废弃物生态足迹的长时间序列动态变化进行特征研究。结果表明（：1）黄山风景区旅游废弃物生态足迹演变具有明显的阶段性特征,共分为1979—1987年持续上升、1988—1996年小范围浮动式下降、1997—2005年剧烈振荡以及2006—2018年趋于稳定四个阶段。（2）黄山风景区旅游废弃物生态足迹的来源及构成占比随着当地垃圾处理方式及污染防治措施的变化而变化。其中,固体垃圾的足迹占比最多且达到52.18%～97.99%,并从显性与隐性两方面对当地生态环境产生影响。（3）随着黄山风景区旅游经济增长,区域资源利用效益持续升高,环境质量稳定改善,始终处于可持续发展状态。（4）黄山风景区的实践表明成熟的环境管理体制和不断改进的卫生治理措施可将旅游废弃物造成的生态影响控制在一定范围之内,从而为其他山岳型景区可持续发展提供有益参考。     

东营市胜利油田工矿废弃地调查与整治潜力分析

当前,城市的快速扩张导致建设用地供需矛盾日益突出,油田工矿废弃地整治作为土地综合整治规划的重要组成部分,在建设用地指标转移、有效耕地面积增加、生态环境改善等方面可以起到积极的作用。因此,为查清东营市胜利油田工矿废弃地的复垦利用潜力,首先对石油开采对土地利用的影响进行了综述,在此基础上确定了胜利油田工矿废弃地的基本类型,进而对工矿废弃地的现状进行了调查,依据废弃地所在区域的规划用途、灌溉条件、排水条件,盐碱程度、区位条件进行了潜力分区和测算,最终获得了东营市胜利油田工矿废弃地潜力测算的相关数据,可以为该区域工矿废弃地的整治及建设用地、耕地指标的流转与保护提供参考依据。