Control of upland bank erosion through tidal marsh construction on restored shores: Application in the maryland portion of Chesapeake Bay

During the period of 1972 through 1993, Environmental Concern Inc. (EC) and its recent (1989) affiliate Environmental Construction Company (ECC) have completed 216 marsh construction projects to control upland bank erosion in tributaries of the Maryland portion of Chesapeake Bay. Of these projects, 26 have involved marsh construction on unaltered existing shores and 190 have utilized marsh construction on shores that have been restored to former increased elevations through shoreline filling and grading. This paper describes the latter restoration technique. Throughout the 21-year period of applying the technique for long-term upland bank erosion control, refinements to the design standards and criteria for site suitability have been made so as to optimize its successful application. As a result of this experience, a reliable bioengineering restoration technique has evolved to control upland bank erosion. This paper describes the details of this successful technique through a review of: (1) its objectives and benefits, (2) suitability of sites for its application, (3) the design of its shore restoration, (4) its construction, (5) its maintenance, and (6) comparison of its cost with those of structural techniques for bank erosion control. Although the technique has only been applied in the Maryland portions of Chesapeake Bay, its applicability should, with modifications, be broadly applicable to all water bodies.     

广深准高速铁路安全管理模式探讨

广深准高速铁路的开通运营，以及广深铁路公司股份制改造，从客观上要求改革与优化铁路安全管理体制，建工新的铁路安全管理模式。本文构造了广深铁路安全管理模式，满足国家确定的“企业负责，行业管理，国家监察，群众监督”的安全工作体制要求，引入风险管理，实行事故保险，提出应该以安全文化作为新模式的软件，优化新的安全管理体制。     

地面水中叶枯灵的高效液相色谱测定

本文采用反相高效液相色谱法，在质控条件下，对河水，塘水两种地面水中叶枯灵的检验方法进行了测试，用Shimapck ODS柱为分析柱，以甲醇：水＝50：50为流动相，并用冰醋酸调PH至4－5，紫外检测波长281nm，两种水样的平均回收率分别为91．7－96．3％，90－95．8％，相对标准偏差为4．3％，最低检出限为0．0261mg/l，为地面水中叶枯灵卫生标准的实施提供了简便，灵敏，正确的配套测试手段。     

高频超声波降解4-氯酚的反应机理及试验研究

探讨了高频超声波（1.7MHz)降解4-氯酚的反应过程和反应机理，研究了高频超声波降解4-氯酚的效果及4-氯酚的初始浓度，高级氧化方法（AOPs)等因素对降解效果的影响。试验结果表明，高频超声波降解4-氯酚为一级反应，超声波空化效应在降解过程中起主导作用。超声波与其他氧化方法联用可大大提高降解效率。具有良好的工业应用前景。     

高温堆肥法处理污泥的探讨

对于污水处理后所产生的污泥,较好的方法是采用无害化、资源化农用技术,利用污泥为原料,制成有机复合肥,不仅解决了污水污泥的处理问题,还可推动环保产业的发展,促进农业生产,具有明显的经济、社会和环境效益。     

大中城市震害预测与辅助决策的空间分析

利用GIS的空间分析功能，对大中城市防震减灾示范研究成果进行了空间区划分析，给出了城市高危害街区的计算方法和结果，同时给出了各种结构类型房屋破坏面积、人员伤亡和无家可归人口数在各个街区的空间分布结果，以及基于此空间分布结果的医疗救护、人员疏散和物资供应等辅助决策分析。该分析的主要意义在于能充分了解大中城市潜在震害的空间分布，为震前采取相应预防措施和震后开展应急救灾工作提供了方便。     

杂交水稻节水高产栽培技术研究

通过多年的试验、示范证明,杂交稻具有旱能保产、湿能增产的特点,特别是在通气式大田水层栽插、湿润管理的条件下,具有节水、增产、改良土壤的作用。对在灌溉条件较差的丘陵山区和圩区发展水稻生产有积极的作用。     

利用城市生活垃圾制取有机复合肥

用城市生活垃圾经好氧高温制成堆肥,并向其中加入无机化肥和微量元素添加剂可制成有机复合肥。本文简要阐述了好氧高温堆肥的生产工艺,推荐了用垃圾生产有机复合肥的两类配方。     

架空管道震害预测实用方法的研究

根据震害调查分析和试验研究结果,建立了由环境因素和管道结构参数组成的,对架空管道震害预测进行二级多因素模糊综合评判的方法。文中给出了计算、评价构成二级评判因素地震烈度、场地类型、工作状态和结构种类各档次正态模糊数范数ａｋ的参数和对实际情况如何确定的方法。本文为面广量大的已建架空管道的震害预测工作提供了一套科学性强,方便实用的计算方法。     

Sensitivity of Ozone Production to the Nmhc Composition, Aerosol Back-Scattering and High Chimney Emission

In this paper, three sensitivity studies are designed to analyze the effect of the NMHC (Non-Methane HydroCarbon) composition, the aerosol back-scattering and the high chimney NO_x emission to the photochemical prodution of ozone by using a one-dimensional photochemistry-diffusion model under a favourable meteorological condition. Measurements of the NMHC composition in Taipei indicated that the percentage of iso-butene, cis-2-butene, trans-2-butene and benzene in a unit volume was much higher than of those observed in other major cities. the high ratio of benzene was directly linked to its high percentage in gasoline. As to the unusually high amount of iso-butene, cis-2-butene and trans-2-butene, more researches are needed to identify their source. Concerns are raised as to how productive is NMHC composition is to the photochemical production of the surface ozone. A rough estimate shows that the total reactivity of the Taipei NMHC composition is about 1.21 × 10^-9 cm³ s^-1 which is 1.6 times that of the Los Angeles (LA) NMHC composition, while the simulated noon peak will be different by 28 ppbv, i.e. 18% more than that simulated with a LA composition.

Meanwhile, high aerosol loading is a serious problem in Taipei. the attenuation of the UV radiation by aerosols cannot be ignored. A numerical simulation shows that the noon ozone level will decrease from 178 to 141ppbv, i. e. about 21% reduction, with deterioration of the visual range from 85 to 5 km.

In the southern Taiwan, industry parks are mixed with the populated Kaohsiung city, hence the large emission of NO_x from high chimneys cannot be ignored. in this study, NO_x is assumed to be emitted in the layer between 235-460 m high with an emission rate of 0.05 or 0.145 ppbv/sec. the results show that the NO_x emitted from the elevated stack lead to a considerable reduction of surface ozone. Such conclusion is obtained due to the fact that a one-dimensional model is used in this paper. Whereas, if a three-dimensional regional model was used, then a higher productivity of ozone downstream would be simulated.