浅谈海域地区节段箱梁预制场场地建设

近年来公路节段箱梁短线匹配法预制施工技术在跨海桥梁施工中得到了广泛应用,文章结合泉州湾跨海大桥实体工程成功实践经验,从梁场的选址、布置及规划,工装设备的配备等方面进行了阐述,以期通过科学、合理的规划布置,达到节约用地,提高机械化施工程度,降低施工成本,节能创效的目的。

保护我国沿海及海域地区的地质环境势在必行

我国地处太平洋西岸,拥有漫长的海岸线和广阔的海域.在大陆的东部有渤海,面积为7700平方公里,平均水深为18米;黄海为38万平方公里,平均水深为44米,东海为77万平方公里,平均水深为370米;

浅谈海域地区电气化铁道绝缘子污闪特征及防治措施

对海域地区电气化铁道绝缘子污闪的成因和特征进行了分析,提出了污闪防治措施,指出绝缘子清扫适合短效绝缘污闪的防治,只有结合现场绝缘子类别和积污情况采取针对性的措施,才能防治绝缘污闪问题。

寒冷地区冰冻海域混凝土桥梁耐久性现场检测及评估

寒冷地区跨海桥梁长期受到氯盐和冻融等环境因素的叠加作用,耐久性问题非常突出。对服役7年的山东某跨海大桥开展耐久性检测,采用多重手段对典型构件混凝土碳化深度、电阻率以及氯离子侵蚀情况进行了分析;通过Fick第二定律和非线性参数拟合,进一步研究了不同腐蚀条件下海工混凝土的氯离子现场扩散系数及分布特征。研究结果表明:掺加粉煤灰和矿粉有效降低了混凝土电阻率,提升了混凝土抗氯离子侵蚀性能;混凝土现场施工采用了表面涂层加透水模板布工艺,可以提升跨海混凝土结构的耐久性;寒冷地区冰冻海域冻融引起的冰涨压力和渗透压力改变了混凝土表层的孔隙结构,增加了混凝土内部的微裂缝和氯离子迁移通道。

生物降解原油中吡咯氮化合物组成的变化

渤海海域地区近50个原油样品中性氮组分的GC/MS定量分析资料表明,油藏中的生物降解作用对原油的吡咯氮化合物含量和分布有明显影响。经与同源未降解原油比较,各种烷基咔唑和苯并咔唑在3～4级中轻度降解油中就出现明显降解迹象,随生物降解程度增高其含量逐渐减少,在6～8级严重降解油中它们的总含量降低到原有的五分之一左右。在3～4级中轻度降解油中,裸露型甲基咔唑异构体更容易被微生物侵袭而代谢,抗生物降解能力按1-甲基咔唑>4-甲基咔唑>2-、3-甲基咔唑顺序递减;当降解程度更高时,这些化合物降解速率相当,1-/4-MCA等比值相对稳定。低—中等降解阶段,不同类型二甲基咔唑异构体的抗生物降解能力也存在明显差异性,呈屏蔽型>半屏蔽型>裸露型降低;在生物降解水平进一步增高时,这些异构体之间的相对含量变化不大。生物降解作用对苯并咔唑系列化合物分布的影响具有不确定性,且随降解程度的增加变得更为显著,降解油中[a]/[c]苯并咔唑比值或增高或降低。生物降解原油中吡咯氮化合物的组成变化,使降解油的二次运移示踪面临新的问题。

Characteristics of Nitrogen and Phosphorus Losses in Different Crop Rotation Systems in the North of Erhai Lake Basin

[Objective] Nitrogen and phosphorus losses of surface runoff in various crop rotation systems in the north of Erhai Lake basin were studied with the objective to provide references for risk evaluation of environmental pollution and formulating countermeasures to control the nonpoint source pollution from agriculture.[Method] Water samples collected in four typical crop rotation systems distributed in seven towns（townships） in the north of Erhai Lake basin were investigated,as well as the fertilizer input,to explore the dynamic change of nitrogen and phosphorus content in surface water of farmland and ditch water,and the correlation between fertilizer input and the concentrations of nitrogen and phosphorus in the surface water of farmland and in the ditch water.[Result] The results showed that nitrogen loss in surface water of farmland in different crop rotation systems differed greatly,and the risk of nitrogen loss was 38% lower in broad bean-rice crop rotation than that in garlic-rice crop rotation.The water soluble nitrogen was the primary form of nitrogen loss.The content of water soluble nitrogen was significantly higher in garlic-rice crop rotation than that in the other rotation systems,and the concentrations of nitrogen in the surface water of farmland in different crop rotation systems followed the sequence below：garlic-rice crop rotationryegrass-rice crop rotationbroad bean-rice crop rotationrape-rice crop rotation.The loss of phosphorus in the surface water of farmland was relatively low and phosphorus combined with silt was the primary form for phosphorus loss.There was no significant difference of the loss of various forms of phosphorus in different crop rotation systems.The contents of total nitrogen and total phosphorus in the surface water of farmland were higher than that in ditch water,with increasing rates of total nitrogen and total phosphorus in ditch water of 72% and 82%,respectively.Topdressing was the critical reason for the high concentrations of nitrogen and phosphorus in the surface water,which also caused the increasing load to the ditch water.[Conclusion] Both the nitrogen and phosphorus loss were the highest in garlic-rice crop rotation.Reasonable crop rotation systems should be established based on both the environmental and economic benefits.This study provided references for controlling the nonpoint source pollution of farmland and improving the water quality of Erhai Lake.

宁波陆源入海排污口优势菌群的数量、组成分析与研究

研究了宁波地区海域2011年3月、5月、8月、10月的排污口污水水体中可培养细菌的数量、组成及其分布,探讨了优势菌群与当地环境的相关关系.结果表明:各地区细菌分布各月份性差异明显,5月份、8月份细菌数量明显高于3月与10月,其均值数量级能达到106cfu mL-1;象山、余姚地区排污口细菌数量高于奉化、宁海、北仑地区,细菌数量最高均值为8月份象山地区排污口(4.7×106cfu mL-1).优势菌群分布具有季节性分布特征:3月份特有优势菌群为假单胞菌属(Pseudomonas sp.)与海单胞菌属(Marinomonas sp.);5月份为假单胞菌属(Pseudomonas sp.)、海单胞菌属(Marinomonas sp.)与弧菌属(Vibrio sp.);8月份为泛菌属(Pantoea sp.)、弧菌属(Vibriosp.)、肠杆菌属(Enterobacter sp.);10月份为不动杆菌属(Acinetobacter sp.)、弧菌属(Vibrio sp.)、希瓦氏菌属(Shewanella sp.).多维尺度分析表明:临近海域类型与排污口类型为排污口细菌群落变化的两个关键因素.

Review of research on interactions between deepwater steel catenary risers and soft clay seabeds

Steel catenary risers （SCR） have become an enabling technology for deepwater environments. A comprehensive review was conducted on recent research that examined interactions between deepwater steel catenary risers and soft clay seabeds. This included the STRIDE （steel risers in deepwater environments） and CARISIMA （catenary riser soil interaction model for global riser analysis） joint jndustry jrogram＇s test data as well as information from existing papers.

海砂换填和强夯排水法处理软土地基施工技术

沿海地区基础设施所在位置大都处于新近吹填海砂区,淤泥土较多,目前针对此类淤泥土地区的地基处理尚无相关技术规程。结合工程实例,介绍了河北曹妃甸港区用海砂换填并将履带式挖掘机配合清运淤泥、试验段施工得出控制参数以及大面积挤淤换填、降水强夯等施工方法相结合进行地基处理的施工工艺及操作要点。

A New Approach to Measurement of Regional Inequality in Particular Directions

Regional inequality is a core issue in geography,and it can be measured by several approaches and indexes.However,the global inequality measures can not reflect regional characteristics in terms of spatiality and non-mobility,as well as correctly explore regional inequality in particular directions.Although conventional between-group inequality indexes can measure the inequality in particular directions,they can not reflect the reversals of regional patterns and changes of within-group patterns.Therefore,we set forth a new approach to measure regional inequality in particular directions,which is applicable to geographic field.Based on grouping,we established a new index to measure regional inequality in particular directions named Particular Direction Inequality index(PDI index),which is comprised of between-group inequality of all data and between-group average gap.It can reflect regional spatiality and non-mobility,judge the main direction of regional inequality,and capture the changes and reversals of regional patterns.We used the PDI index to measure the changes of regional inequality from 1952 to 2009 in China.The results show that:1) the main direction of China's regional inequality was between coastal areas and inland areas;the increasing extent of inequality between coastal areas and inland areas was higher than the global inequality;2) the PDI index can measure the between-region average gap,and is more sensitive to evolution of within-region patterns;3) the inequality between the northern China and the southern China has been decreasing from 1952 to 2009 and was reversed in 1994 and 1995.

Impact of Autumn SST in the Japan Sea on Winter Rainfall and Air Temperature in Northeast China

We studied the impact of sea surface temperature anomaly(SSTA) in the Japan Sea and the sea area east of Japan on the winter rainfall and air temperature in Northeast(NE) China using the singular value decomposition(SVD) and empirical orthogonal function(EOF). The monthly-mean rainfall data observed at 160 stations in China, monthly-mean sea surface temperature(SST) of the Hadley Center for Climate Prediction and Research and monthly-mean air temperature from the NCEP reanalysis during 1960–2011 were used. Correlation analysis indicates that the SSTAs in the Japan Sea in September may last for three or four months and are an important index for forecasting the winter rainfall and air temperature in NE China. Positive SSTAs in the central Japan Sea and in the sea area east of Tokyo correspond to positive rainfall anomaly and negative air temperature anomaly in NE China. With the rise of SST in the Japan Sea, a weak cyclone appears over the Japan Sea. The northeasterly wind transports water vapor from the Okhotsk to NE China, resulting in more rainfall and lower air temperature. Negative SSTA years are accompanied by warmer air temperature and less snow in NE China. The 1000 h Pa geopotential height anomaly and wind anomaly fields are simulated by IAP-9L model, which supports the analysis results.

Approach to Delimiting Metropolitan Regions' Boundary and Grading Urban Hierarchy Within a Metropolitan Region——A Case Study of Shanghai Metropolitan Region

In metropolitan regions, the change in the strength of "flows" between a core city and surrounding cities re-flects the range of the core city's influence, while the gravity between core city and other cities reflects the strength of potential relation between them. This article firstly attempts to delimit the boundary of metropolitan regions with the two dimensions measure combining "flows" and gravitation. The former is measured through the flow of people be-tween the core city and surrounding cities, and the latter is measured through both population and gross domestic products (GDP) of the core city and surrounding cities. The hierarchy of the cities within a metropolitan region is classified in order to emphasize the roles of the cities belonging to the metropolitan regions, different from the general way through population scale and administrative level, and is typical in China. This paper uses the Shanghai metropolitan region as a research case, determining boundary of this metropolitan region clearly and classifying hierarchy of the cities within the region. The final results are significantly different to previous work, even overthrowing the traditional system of urban hierarchy partly. It is helpful to highlight the function of cities in organizing the regional economy, the level structure of metropolitan regions, and each city's relative importance in a metropolitan region, which can be taken as scientific basis for planning integrated regions or urban systems.

A Preliminary Study on the New Activity Features of the Lajishan Mountain Fault Zone in Qinghai Province

The Lajishan Mountain fault zone consists of two NE_protruding arcuate faults, i.e. the northern and southern margin fault of Lajishan Mountain with the fault length of 230km and 220km respectively. The fault zone is located in the large_scale compressional structure zone and tectonic gradient zone in_between the NNW_trending right_lateral strike_slip Reshui_Riyueshan fault zone and the NWW_trending left_lateral strike_slip northern margin of west Qinling Ranges fault zone is also an important boundary fault zone, separating the Xining_Minhe basin and the Xunhua_Hualong basin at the southern and northern sides of the Lajishan Mountain respectively. Geologic geomorphic evidences of new activity revealed by field investigations indicate that the latest movement of the Lajishan fault zone was in late Epipleistocene (only a few segments were active in early Holocene) and is mainly of compressive thrusting with slightly left_lateral strike_slip component. The above movement has possibly resulted in the occurrence of about 20 moderate earthquakes of magnitude around 5.0. The Lajishan region can therefore be regarded as a seismotectonic window to reflect tectonic movement and earthquake activity.

The application of environmental economics in marine functional zoning and coastal city conceptual planning

There are a lot of functions of marine resources. The various and competing conflicts between different users and different sectors in the use of marine resources will cause the disorderly development of marine resources, and even destroy the marine ecosystem. Marine functional zoning is an effective tool to solve the conflicts. However, there are some shortcomings in the current understanding on marine functional zoning and its practice. In this paper, a case study on the resource-oriented marine functional zoning of Xiangshan Port is introduced. By the principles of resource-oriented and public participation, Xiangshan Port is divided into seven zones, and the main function of the whole port and seven zones are determined by the environmental economics analysis. A case study of Xiamen is also introduced for how to integrate marine functional zoning into a coastal city conceptual planning. Under the conservation principle, resources-oriented principle and so on, the advantages and disadvantages of natural ecosystem, social ecosystem and economic ecosystem are holistically analyzed, the urban orientation of Xiamen is determined as a regional international tourism city, and the whole city is divided into five function zones according to its leading industry -tourism. Resource-oriented marine functional zoning has a long-term guidance for sustainable use of marine resources and development strategy of a coastal city. And environmental economics analysis is an effective tool for resource-orientation.

Suspended sediment concentration mapping based on the MODIS satellite imagery in the East China inland, estuarine, and coastal waters

The purpose of this research is to improve the retrieval accuracy for the suspended sediment concentration(SSC) from in situ and satellite remote sensing measurements in turbid East China estuarine and coastal waters. For this aim, three important tasks are formulated and solved: 1) an estimation of remote-sensing reflectance spectra R_(rs)(λ) after atmospheric correction; 2) an estimation of R_(rs)(λ) from the radiometric signals above the air-water surface; and 3) an estimation of SSC from R_(rs)(λ). Six different models for radiometric R_(rs)(λ) determination and 28 models for SSC versus R_(rs)(λ) are analyzed based on the field observations made in the Changjiang River estuary and its adjacent coastal area. The SSC images based on the above-mentioned analysis are generated for the area.

A Study on Marine Region Carrying Capacity and Eco-compensation

With the using up of land resources, people are beginning to pay attention to the exploitation of the ocean and the use of marine resources is becoming more and more intense. Whether and how the ocean can be sustainably exploited as it is being exploited is an academic hot topic. This question is addressed in this paper based on the theories of carrying capacity of a marine region and marine eco-compensation, and the amount of the loss is calculated by the method of Time Value of Capital. This thesis covers the study of eco-compensation between two specific subjects with clear compensation objects, and as a defined approach and standard, the proposed method has good operability and positive practical significance in the good use of the ocean.

Two new records of Spiochaetopterus Sars, 1856 (Chaetopteridae, Polychaeta) from Chinese waters

The present paper records two chaetopterid species, S piochaetopterus koreana and S. sanbanzensis not reported previously from China Seas. S piochaetopterus koreana is distributed in the Yellow, East China and South China Seas. Sp iochaetopterus sanbanzensis is widely distributed in the muddy benthic environment of the Yellow Sea. Detailed descriptions and illustrations of each species are provided.

PH_3 monitoring in Arctic and Dalian bay areas

In this paper, we use pre-column 2 times low-temperature cryo-trap enrichment--gas chromatography（GC） /nitrogen and phosphorus detector（NPD）to detect and analyze phosphine in Arctic pole area for the first time. The results show phosphine exists in all of the samples in Arctic pole biosphere and phosphine concentration in Arctic atmosphere is between 18.54- 132.18 ng/m^3, almost the same as that in Antarctic atmosphere; phosphine concentration in Dalian bay sea surface sediments is between 116. 8- 554.3 ng/kg, almost the same as that reported in Jiao-zhou bay. Our research of phosphine will shed new light on the mechanisms showing how the phosphorus supplement influences the biogeochemical cycle and global warming.

Quantitative Seismic Risk Evaluation on Blind Faults in Offshore Areas of Tianjin,China

Based on faults surveying and research data in the Tianjin offshore areas,through studying tectonic structure,Quaternary activity,deep structure,stress and strain fields and seismicity in the Tianjin offshore areas,the activity and tectonic features of the faults are determined synthetically.Using seismo-geological data,and the historical and modern seismicity data,the frequency-magnitude relationship model normalized by 500a is established and based on the relationship between the upper limit of maximum magnitude M u and a t/b,the maximum magnitudes of the sea section of the Haihe river fault and the Haiyi fault are calculated.Then Poisson probability model is adopted and the quantitative parameters,such as the maximum magnitude,occurrence probability,recurrence cycle of the faults in the south Tianjin offshore areas in the coming 50～200a,are calculated.

The interactive development of economy in Hebei coastal region and local universities

This article taking national current affairs decisions as entry points, the theory related to regional economy as basis, analyzes the development relation between regional economy and local universities, thus puts forward countermeasures to achieve the interactive and coordinating development of Hebei coastal regional economy and local universities.