枸杞外观品质与气象条件的关系

利用 2 0 0 0～ 2 0 0 1年枸杞实验资料及相应的气象观测资料 ,通过统计分析方法 ,进行相关普查 ,确定影响枸杞外观品质包括坏果率、百粒重、百粒长的气象因子 ,研究单因子与枸杞外观品质的定量关系。在此基础上 ,建立枸杞外观品质与气象条件的综合定量关系。为从气象条件上改进枸杞商品品质 ,提高种植效益服务。     

Remediation of TCE-contaminated groundwater using zero valent iron and direct current: experimental results and electron competition model

The objectives of this study are to design an optimal electro-enhanced permeable reactive barrier (E2PRB) system for the remediation of trichloroethylene (TCE)-contaminated water using zero valent iron (ZVI) and direct current (DC) and to investigate the mechanisms responsible for TCE degradation in different ZVI-DC configurations. A series of column experiments was conducted to evaluate the effect of different arrangements of electrodes and ZVI barriers in the column on the TCE removal capacity (RC). In twelve different combinations of ZVI and/or DC application in the test columns, the rate of reductive dechlorination of TCE was improved up to six times with simultaneous application of ZVI and DC compared to that using ZVI only. The most effective arrangement of electrode and ZVI for TCE removal was the column set with ZVI and a cathode installed at the down gradient. Based on the electrokinetic study for the column systems with only DC input, single acid front movement could explain different RCs. An enhanced dechlorination rate of TCE using E2PRB systems, compared to a conventional PRB system, was observed, and is considered to be attributed to more electron sources: (1) external DC, (2) electrolysis of water, (3) oxidation of ZVI, (4) oxidation of dissolved Fe²⁺, (5) oxidation of molecular hydrogen at the cathode, and (6) oxidation of Fe²⁺ in mineral precipitates. Each of these electron sources was evaluated for their potential influencing the TCE RC through the electron competition model and energy consumption. A strong correlation between the quantity of electrons generated, RC, and the energy-effectiveness was found.     

外强迫引起的夏季大气环流异常及其机制探讨

本文主要探讨了夏季模式大气对热带海温和高纬极冰异常的外强迫响应机制,结果表明,在大气环流模式长时间积分以后,不同的外强迫源均可在全球大气的一些关键性区域激发产生相同的环流异常型,即夏季大气主要异常型对外强迫源地理位置不敏感,很大程度上依赖于大气内部动力学过程.根据以上特点本文提出外强迫引起大气异常存在两类机制,其中外强迫和大气内部动力学过程相互作用机制是产生大气异常的重要动力学途径.     

大地重力学关于场源研究的方法,进展及面临的问题

将大地重力学的理论、方法加以拓展使其研究范畴深入至对地球内部引力场源的探求，是现代大地重力学深入发展及与地球物理相互渗透的迫切需要。近年来，国际大地重力学界已将该研究作为学科的重要分支，即大地重力学反问题，对该研究的学科发展背景、概念及原理、研究途径及方法、具代表性的赋值模式、主要结果、最新进展及在大地重力学与地球物理学相结合的进程中所起的作用和有待解决的问题进行了较为详尽的综述。     

Airline Network Carbon Emission Model and the Analysis of External Factors

In the face of the challenges posed by low-carbon aviation development to the aviation industry and the transformation of the emission reduction mechanism, based on the external perspective, firstly, the general expression of the environment damage model of aviation carbon emission and the element about the damage factors of carbon emission environment and the application of sensitivity analysis method were introduced and analyzed. Then, the external factors of carbon emissions in the airline network were analyzed systematically—The influence of the flight operation stage (LTO phase and cruise phase), the sector distance, the flight type and the terminal area airspace. The existing research showed that the two types of airline network model about the environment damage of aviation carbon emission were in different ways and sizes, and the city-pairs was lower than the hub-spoke; the environment damage of aviation carbon emission was the formation of the above four elements with the aircraft type and airline type. The hub airport’s carbon emissions triggered a challenge to the hub-spoke airline network model. In the low-carbon economy, corresponding suggestions on the airline network model were also faced with the hinterland market.     

过去2000年东亚夏季风降水百年际变化特征及成因的模拟研究

利用地球系统模式CESM过去2 000年气候模拟试验结果,探讨了在百年尺度上东亚夏季风降水的时空变化特征及其成因,对于认识百年尺度气候变化规律、区分外强迫因子对东亚季风的影响有着重要的科学意义。研究表明:1东亚夏季风降水与温度基本同相变化,降水存在准100年、准150年和准200年周期。2降水标准化EOF第一模态为由北向南"负—正—负—正"的条带状空间分布,而EOF第二模态基本为全区一致的分布型态。3东亚夏季风降水准100年周期主要受太阳辐射、火山活动和气候系统内部变率的共同影响;准150年周期主要受太阳辐射的影响;准200年周期主要受太阳辐射和火山活动的影响。东亚夏季风降水在温带地区主要受温室气体和土地利用/覆盖的影响;在副热带地区主要受太阳辐射和火山活动的影响;在热带地区主要受太阳辐射、火山活动和气候系统内部变率的影响。     

Scenario Prediction of China’s Oil Resource Demand in 2020-2030

Oil plays an important role in ensuring national energy security. It is of great significance for China’s energy policy-making to predict the future oil demand scientifically. Combined with the grey correlation analysis and combination model of ARIMA-BP neural network, data on six driving variables of China’s GDP, international oil price, energy consumption per unit GDP, industrial structure, urbanization rate and oil production in 1999-2018 were selected to predict China’s oil demand under different scenarios in 2020-2030. The results show that the selected driving variables are highly correlated with China’s oil demand, and the combined model is more accurate than the single model. From 2020 to 2030, China’s oil demand and import will continue to increase, but the growth rate will gradually slow down. Under the three scenarios, the predicted average oil demand in 2020, 2025 and 2030 will be 675.7703 million tons, 732.2725 million tons and 760.8155 million tons, respectively; the predicted average external dependence in 2020-2030 will be 76.19%, far exceeding the international warning line of 50%. The contradiction between China’s oil supply and demand will be more acute, and accordingly, some policy suggestions were put forward.     

The Study of Two Geomagnetic Jerks in China

This paper analyzes the first differences of the annual means (annual rate) for the Y and Z components of the geomagnetic field from nine magnetic observatories in China, measured from 1985 to 2003. The 1991 jerk was obvious in the Y component measured but not clear for the Z component. Rapid changes in the Z components were ubiquitous around 2000 -2001, but not seen for the Y component. External effects were removed from the monthly means by comparing the monthly mean of the geomagnetic field components at the observatories with the monthly time series of the Ap geomagnetic index. However, some examples were analyzed and showed whether external effects were removed or not, there was no marked distinction in determining the jerks in China for the Y component and the Z component of the geomagnetic field. Finally, the isolines of the first differences of the annual means were used to analyze the spatial and temporal distributions of the jerks.     

外源S_q等效电流体系电流涡中心电流强度与太阳活动关系

本文选取了INTERMAGNET地磁台网2001年到2012年的地磁数据,对其进行世界时(UT)到地方时(LT)的转换后利用自然正交分量法(NOC)从所选资料中提取出太阳静日变化Sq成分,再通过球谐分析方法建立模型分离内、外源Sq成分,逐日反演出内、外源Sq等效电流体系,并得到外源Sq等效电流体系南北电流涡中心电流强度.本文将外源Sq等效电流体系南北电流涡中心电流强度与同一时期的Dst指数进行了对比分析,研究表明它们之间具有同步变化的规律,且北半球电流涡中心电流强度在磁暴发生时的异常现象远高于南半球.对F10.7cm太阳射电流量与外源Sq等效电流体系南、北半球电流涡中心电流强度的长短周期分析发现,Sq等效电流表现出明显的11年周期特点,与太阳活动周期一致.外源南、北半球电流涡中心电流强度和F10.7cm年均值的相关系数分别达到了0.93和0.90,说明太阳活动是导致外源Sq电流体系变化的最直接也最主要的因素,这可能与电离层电导率受控于太阳的电磁辐射相关.     

Prospects of interventions to alleviate rural–urban migration in Jiangsu Province,China based on sensitivity and scenario analysis

ABSTRACT

Rural–urban migration is an adaptive response to location-specific environmental or socio-economic stressors. Jiangsu Province, China is witnessing rapid economic growth fuelled by manufacturing and services sector. Rural–urban migration in Jiangsu, which brings higher stress to resource-carrying capacity of urban areas, is driven by rural “push” factors, principally labour surplus and unemployment in agriculture. This study investigates possible policy interventions aimed at relieving the rapid rural–urban migration in Jiangsu based on a sensitivity analysis of driving factors in rural agricultural production. It shows that rural–urban migration is sensitive to input elasticities of precipitation and labour. Two groups of scenario analysis corresponding to possible policy interventions are implemented. The first policy focuses on providing government subsidies to rural non-agricultural industries then compensate for the shrinking agricultural production. Another policy supports education in rural areas to provide more skilled labour resource which can be absorbed by non-agricultural industries. Both two policies are effective in reducing rural unemployment and alleviating rural–urban migration.