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Search Results: 1 - 10 of 303617 matches for " <br>宋利娜 "
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非对称放行方式下的干道双向绿波协调控制
,清华
公路交通科技 , 2011,
Abstract: 通过对对称放行和非对称放行两种方式下的双向绿波设计进行比较,针对非对称放行方式的特点,根据绿波协调控制需求,进行独特的搭接相位设计,并在相位差的计算过程中考虑各路段行驶车速和红灯排队车辆的影响。在此基础上,提出了一种新的干道绿波协调控制实用设计方案,并通过其在昆明市滇池路上的应用验证了其准确性与有效性。
Atomic-scale study of structural change of TiAl alloy film during the cooling process
TiAl合金薄膜在冷却过程中结构变化的原子尺度计算研究

Song Cheng-Fen,Fan Qin-N,Li Wei,Liu Yong-Li,Zhang Lin,<br>成粉,樊沁,李蔚,刘永,张林
物理学报 , 2011,
Abstract: Microstructural changes of molten TiAl films are investigated by using molecular dynamics simulations within the framework of embedded atom method in quenching and continuous cooling processes. Atomic local structures in these films are analyzed by using atom average energy, pair distribution functions, and pair analysis technique. The local structure changes in the TiAl films can be divided in to three stages on quenching, and they are divided in to two stages on continuous cooling.
Comprehensive analysis of emissions and global warming effects of greenhouse gases in winter-wheat fields in the high-yield agro-region of North China Plain
华北平原高产农区冬小麦农田土壤温室气体排放及其综合温室效应

SONG Li-N,ZHANG Yu-Ming,HU Chun-Sheng,ZHANG Xi-Ying,DONG Wen-Xu,WANG Yu-Ying,QIN Shu-Ping,<br>,张玉铭,胡春胜,张喜英,董文旭,王玉英,秦树平
中国生态农业学报 , 2013,
Abstract: Comprehensive studies on greenhouse gas emissions and the related global warming potential (GWP) under different agricultural management practices had the benefits of mitigated greenhouse gas emissions, reduced GWP and strengthened theoretical basis for measurements of greenhouse gas emissions. Based on experiment with four agricultural management patterns (T1: conventional pattern; T2: high-yield and high-efficiency pattern; T3: super-high-yield pattern; T4: super-high-yield, high-efficiency and soil fertility improvement pattern), N2O, CO2 and CH4 fluxes in winter-wheat fields were monitored from October 2009 to September 2011 using the static chamber method and the gas chromatographic technique. Total greenhouse gas emissions and GWP were then accordingly estimated. The results indicated that the winter-wheat field was the sources of N2O and CO2, but the sink of CH4. The effects of the different agricultural management patterns on the different greenhouse gas sources and sinks were different. High N application and sufficient irrigation increased the CO2 and N2O in the soil and strengthened the characteristics of soil as the emission source of CO2 and N2O. Meanwhile, CH4 oxidation in soils was restrained and soil characteristics as CH4 sink decreased. The carbon equivalent of emitted greenhouse gases in treatments T1, T2, T3 and T4 in 2009-2010 were respectively 8 880 kg(CO2)·hm-2, 8 372 kg(CO2)·hm-2, 9 600 kg(CO2)·hm-2 and 9 318 kg(CO2)·hm-2; and 13 395 kg(CO2)·hm-2, 12 904 kg(CO2)·hm-2, 13 933 kg(CO2)·hm-2 and 13 189 kg(CO2)·hm-2 in 2010-2011. Differences in greenhouse gas emissions among different treatments were caused by different fertilization and irrigation managements. Straw return or non-return largely led to the differences in greenhouse gas emissions between 2009-2010 and 2010-2011. GWP was relatively low while yield and input-output ratio relatively high in T2. Treatment T2 was therefore considered the optimal management mode for winter-wheat cultivation in the North China Plain.
Effect of fertilization and irrigation on wheat-maize yield and soil nitrate nitrogen leaching in high agricultural yield region in North China Plain
水肥耦合对华北高产农区小麦-玉米产量和土壤硝态氮淋失风险的影响

ZHANG Yu-Ming,ZHANG Jia-Bao,HU Chun-Sheng,ZHAO Bing-Zi,ZHU An-Ning,ZHANG Li-Zhou,SONG Li-Na,<br>张玉铭,张佳宝,胡春胜,赵炳梓,朱安宁,张立周,
中国生态农业学报 , 2011,
Abstract: Field experiment with several coupled fertilization and irrigation treatments was conducted in State Experimental Station of Agro-Ecosystem in Fengqiu.Effect of fertilization and irrigation on wheat-maize yield,distribution of nitrate nitrogen in soil profile and the risk of nitrate nitrogen leaching under wheat-maize rotation system was studied.The results indicated that reasonable combined application of nitrogen and phosphorus fertilizers was the key to improve crop yield under appropriate irrigation rat...
Research advances on source/sink intensities and greenhouse effects of CO2, CH4 and N2O in agricultural soils
农田土壤主要温室气体(CO2、CH4、N2O)的源/汇强度及其温室效应研究进展

ZHANG Yu-Ming,HU Chun-Sheng,ZHANG Jia-Bao,DONG Wen-Xu,WANG Yu-Ying,SONG Li-Na,<br>张玉铭,胡春胜,张佳宝,董文旭,王玉英,
中国生态农业学报 , 2011,
Abstract: 气候变化是当今全球面临的重大挑战, 人类社会生产生活引起的温室气体排放是全球气候变暖的主要原因。大气中CO2、CH4 和N2O 是最重要的温室气体, 对温室效应的贡献率占了近80%。据估计, 大气中每年有5%~20%的CO2、15%~30%的CH4、80%~90%的N2O 来源于土壤, 而农田土壤是温室气体的重要排放源。本文重点阐述了农田土壤温室气体产生、排放或吸收机理及其影响因素, 指出土地利用方式和农业生产力水平等人为控制因素通过影响土壤和作物生长条件来影响农田土壤温室气体产生与排放或吸收。所以, 我们可以从人类活动对农田生态系统的影响着手, 通过改善农业生产方式和作物生长条件来探索温室气体减排措施, 达到固碳/氮增汇的目的。对国内外关于农田温室气体排放的源/汇强度及其综合温室效应评估的最新研究进展进行了综述, 指出正确估算与评价农田土壤温室气体的源/汇强度及其对大气中主要温室气体浓度变化的贡献, 有助于为温室气体减排以及减少气候变化预测的不确定性提供理论依据。
GPS时间序列中同震和震后形变的自动识别和估计
Automatic Detection and Estimation of Coseismic and Postseismic Deformation in GPS Time Series

, 张勇<br>SU Lina, ZHANG Yong
- , 2018, DOI: 10.13203/j.whugis20170016
Abstract: 地震发生时,附近GPS观测站会捕捉到同震和震后形变,同震和震后形变对地学研究和维持动态参考框架具有重要作用,识别和估计同震和震后形变也是GPS时间序列处理的重要内容。提出综合检校法识别和估计GPS时间序列中的同震和震后形变,首先利用该方法对GPS站建模,综合考虑多源的同震阶跃及兼容性和均方根RMS减小率来判断测站是否受到地震影响,然后用试错法搜索最优衰减常数τ后,利用最小二乘估计包含同震和震后形变的所有参数,最后以真实震例验证了该方法的有效性
Cultivated Land Quality Assessment Based on SPOT Multispectral Remote Sensing Image:A Case Study in Jimo City of Shandong Province
基于SPOT多光谱影像的耕地质量评价——以山东省即墨市为例

FANG Linna,SONG Jinping,<br>方琳,金平
地理科学进展 , 2008,
Abstract: The cultivated land quality assessment study was carried out in Jimo city,Shandong Province,based on SPOT multispectral remote sensing image(2004) and data using in cultivated land fertility survey in 2004.Cultivated land quality assessment indicators were abstracted from SPOT multispectral image,e.g.NDVI,DVI and RVI,which represented soil fertility,water availability and soil degradation respectively.The assessment indicator system was constructed using the indicators mentioned above.By virtue of PSR framework,the assessment model was developed in order to explore the feasibility of RS technology in cultivated land quality assessment.The result showed that local cultivated land prevalently had a good quality.This paper classified the local cultivated land into six grades and corresponding suggestions were put forward respectively to promote policy making for land protection.The paper showed that the model was competent for its work in the study area and evaluation results would supply beneficial information for sustainable land management.
Measuring Spatial Accessibility to Health Care Facilities Based on Potential Model
基于潜能模型的医疗设施空间可达性评价方法

SONG Zhengna,CHEN Wen,<br>,陈雯
地理科学进展 , 2009,
Abstract: Access to health service is recognized as an important facilitator of overall population health, and spatial accessibility is one of the vital indexes to assess whether the distribution of health care facilities is balanced or not. Traditional methodology to assess spatial accessibility usually focuses on alternative of the ratio of supply (provider) versus demand (population) in the administrative unit or the travel impedance between population and health service providers. However, both of them can't be comprehensive to reveal the health care resource quantity which any population location can access due to travel impedance. In the paper, we use the measure of spatial accessibility based on potential model to analyze spatial accessibility from village population location to hospitals with Universal Kriging to interpolate the accessibility values in Rudong County of Jiangsu Province, which integrates three main factors including the service capacity of health care facilities, the population demand impact factor and travel impedance between population location and provider location. Through our study, the following conclusions are reached: after selecting the proper travel friction coefficient which is the key factor to affect sensitively the accuracy of spatial accessibility results when using potential model, the measure of spatial accessibility based on potential model can be more comprehensive and accurate to measure spatial accessibility to health care facilities among the small units of the studied area in the spatial interaction between population and service providers, and by GIS, the methodology is able to reveal directly the difference of spatial accessibility to health care facilities in the studied area, furthermore, health professional shortage areas of the studied area can be defined effectively with certain standards developed by public health management sector, which can support the basis for decision-making of health service planning.
LncRNA HOTAIR 表达水平与肿瘤患者预后关系的 Meta 分析
Prognostic value of lncRNA HOTAIR expression in patients with cancer: A Meta-analysis

席文,伟<br>XI Wenna, SONG Wei
- , 2016, DOI: 10.11817/j.issn.1672-7347.2016.12.017
Abstract:
Study on Reproductive Toxicity of Perfluorooctane Sulfonate(PFOS)in Female Quail
全氟辛烷磺酸对雌鹌鹑的生殖毒性研究

锦兰,金一和,李晓,,于红瑶
生态毒理学报 , 2008,
Abstract: 为了探讨全氟辛烷磺酸(PFOS)对雌性禽类的生殖毒性,以雌鹌鹑为禽类指示动物进行了PFOS经口染毒实验.染毒组PFOS染毒剂量分别为12.5、25.0、50.0mg·kg-1(以饲料中的PFOS计),同时设对照组,连续染毒71天,检测体重、产卵率、受精率、孵化率及雏鹌鹑死亡率、畸形率等指标.结果表明,染毒第33天起50.0mg·kg-1剂量组雌鹌鹑体重显著低于对照组(p<0.01),并出现死亡;各染毒组开始产卵时间均滞后于对照组,产卵率均低于对照组;各染毒组雌鹌鹑受精率、孵化率、孵化12h后雏鹌鹑体重均低于对照组,雏鹌鹑畸形率、孵化后12h内雏鹌鹑死亡率均高于对照组;随着染毒剂量的增加,雌鹌鹑血清及卵黄中PFOS含量也相应升高,均呈显著正相关(P<0.01);各染毒组雌鹌鹑开始产卵5天内所产卵中PFOS含量均显著高于实验结束前3天所产卵(p
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