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广元烟区烤烟化学成分年度间变异分析 被引量:2
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作者 顾会战 鲁黎明 吴绍军 《安徽农业科学》 CAS 北大核心 2010年第34期19305-19307,共3页
分析了2006~2008年广元烟区烤烟主要化学成分的年度变异情况。结果表明,广元烤烟总糖和还原糖含量呈逐年增加趋势,年度间差异明显;总植物碱与总氮含量呈逐年下降趋势,但均在适宜的含量范围内;钾含量偏低,且年度间变化较小;糖碱比逐年增... 分析了2006~2008年广元烟区烤烟主要化学成分的年度变异情况。结果表明,广元烤烟总糖和还原糖含量呈逐年增加趋势,年度间差异明显;总植物碱与总氮含量呈逐年下降趋势,但均在适宜的含量范围内;钾含量偏低,且年度间变化较小;糖碱比逐年增加,年度间差异明显。 展开更多
关键词 烤烟 化学成分 年度变异 广元
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美国硬红冬和硬红春小麦籽粒品质比较及与中国强筋小麦标准对标分析
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作者 蒋佳丽 刘丰 +8 位作者 谢凯 周琴 蔡剑 王笑 黄梅 仲迎鑫 戴廷波 曹卫星 姜东 《麦类作物学报》 CAS CSCD 北大核心 2024年第5期594-604,共11页
随着人们消费结构的改变,面包市场发展迅速,但中国优质强筋小麦生产供应不足,质量差异较大,而美国硬麦有良好的加工性能和稳定的品质,制粉和烘焙特性优异。研究美国硬红冬小麦和硬红春小麦籽粒品质年度间变化特点及品质指标间相关性,可... 随着人们消费结构的改变,面包市场发展迅速,但中国优质强筋小麦生产供应不足,质量差异较大,而美国硬麦有良好的加工性能和稳定的品质,制粉和烘焙特性优异。研究美国硬红冬小麦和硬红春小麦籽粒品质年度间变化特点及品质指标间相关性,可为中国强筋小麦籽粒品质研究与发展提供参考。本文汇总了美国小麦协会1999—2021年间发布的硬红冬小麦、硬红春小麦品质相关性状数据,分析了两类小麦品质指标间相互关系,并探讨了美国硬麦品质对中国现有强筋小麦标准的适配度。结果表明,与硬红冬小麦相比,硬红春小麦蛋白含量高,筋力强,形成时间、稳定时间等面团品质更高,烘焙品质更优,且籽粒、面粉品质稳定性高。对标中国强筋小麦标准可以发现,硬红春小麦对标中国强筋小麦标准的达标率高于硬红冬小麦,蛋白含量、湿面筋达标率差距尤为明显。综合考虑中国强筋小麦生产现状,并结合美国硬麦对中国强筋小麦标准达标率,中国强筋小麦标准可将蛋白含量调整为>14.5%,湿面筋含量为>32.0%,稳定时间>10 min,容重、硬度分别大于760 g·L^(-1)和65。硬红春小麦品质指标的相关性分析显示,拉伸面积与面包烘焙吸水率显著负相关,与面包体积显著正相关,可用于预测强筋小麦面包品质;中国标准可设置拉伸面积为105 cm^(2)。 展开更多
关键词 硬红冬小麦 硬红春小麦 品质性状 年度变异 达标度
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年度间收缩压变异性与体位性低血压的相关性 被引量:3
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作者 高竞生 李志芳 +7 位作者 吴云涛 赵海燕 阮春雨 赵华灵 宋路 李春慧 陈朔华 吴寿岭 《中华高血压杂志》 CAS CSCD 北大核心 2016年第3期245-249,共5页
目的探讨年度间收缩压变异性(ASBPV)与体位性低血压(OH)的相关性。方法 2006-2007年第1次对开滦集团公司在职及离退休职工进行健康体检,此后分别于2008-2009、2010-2011年进行第2、3次健康体检,并于第3次体检时按25%的比例随机分层... 目的探讨年度间收缩压变异性(ASBPV)与体位性低血压(OH)的相关性。方法 2006-2007年第1次对开滦集团公司在职及离退休职工进行健康体检,此后分别于2008-2009、2010-2011年进行第2、3次健康体检,并于第3次体检时按25%的比例随机分层抽取年龄≥60岁的开滦集团离退休员工进行卧立位血压等检查。符合入选标准及资料完整的2050人纳入统计分析。ASBPV采用2006-2007、2008-2009、2010-2011年度的收缩压值的标准差计算。采用多因素Logistic回归分析不同ASBPV水平对OH的影响。结果 2050人(男性1385人,女性665人)平均年龄为67.5岁。按照ASBPV三分位数(6.34、12.41mm Hg)将研究对象分为3组,随着ASBPV水平的升高,OH检出率逐渐上升(18.9%、20.2%、24.9%;P=0.017)。多因素Logistic回归分析显示:校正了年龄、性别等因素后,与ASBPV第1三分位组相比,第3三分位组为OH的危险因素(OR=1.37,95%CI 1.03~1.81)。结论 ASBPV与OH发病呈正相关。 展开更多
关键词 年度间收缩压变异 体位性低血压 老年人
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Variability of Tropical Cyclone in High Frequent Occurrence Regions over the Western North Pacific 被引量:1
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作者 YANG Yuxing HUANG Fei WANG Faming 《Journal of Ocean University of China》 SCIE CAS 2014年第3期347-355,共9页
In this study, three high frequent occurrence regions of tropical cyclones(TCs), i.e., the northern South China Sea(the region S), the south Philippine Sea(the region P) and the region east of Taiwan Island(the region... In this study, three high frequent occurrence regions of tropical cyclones(TCs), i.e., the northern South China Sea(the region S), the south Philippine Sea(the region P) and the region east of Taiwan Island(the region E), are defined with frequency of TC's occurrence at each grid for a 45-year period(1965–2009), where the frequency of occurrence(FO) of TCs is triple the mean value of the whole western North Pacific. Over the region S, there are decreasing trends in the FO of TCs, the number of TCs' tracks going though this region and the number of TCs' genesis in this region. Over the region P, the FO and tracks demonstrate decadal variation with periods of 10–12 year, while over the region E, a significant 4–5 years' oscillation appears in both FO and tracks. It is demonstrated that the differences of TCs' variation in these three different regions are mainly caused by the variation of the Western Pacific Subtropical High(WPSH) at different time scales. The westward shift of WPSH is responsible for the northwesterly anomaly over the region S which inhibits westward TC movement into the region S. On the decadal timescale, the WPSH stretches northwestward because of the anomalous anticyclone over the northwestern part of the region P, and steers more TCs reaching the region P in the greater FO years of the region P. The retreating of the WPSH on the interannual time scale is the main reason for the FO's oscillation over the region E. 展开更多
关键词 high frequent occurrence regions frequency of tropical cyclone's occurrence western Pacific subtropical high
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Interannual Climate Variability of the Past Millennium from Simulations
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作者 YANG Kai-Qing JIANG Da-Bang 《Atmospheric and Oceanic Science Letters》 CSCD 2015年第3期160-165,共6页
The interannual variability of global temperature and precipitation during the last millennium is analyzed using the results of ten coupled climate models participating in the Paleoclimate Modelling Intercomparison Pr... The interannual variability of global temperature and precipitation during the last millennium is analyzed using the results of ten coupled climate models participating in the Paleoclimate Modelling Intercomparison Project Phase 3. It is found that large temperature(precipitation) variability is most dominant at high latitudes(tropical monsoon regions), and the seasonal magnitudes are greater than the annual mean. Significant multi-decadal-scale changes exist throughout the whole period for the zonal mean of both temperature and precipitation variability, while their long-term trends are indistinctive. The volcanic forcings correlate well with the temperature variability at midlatitudes, indicating possible leading drivers for the interannual time scale climate change. 展开更多
关键词 interannual variability volcanic impacts last millennium
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A study on variations of non-dipole magnetic field over Chinese mainland during 2000 BC to 1990 AD 被引量:1
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作者 FENG Yan JIANG Yong +2 位作者 SUN Han AN ZhenChang MAO Fei 《Science China Earth Sciences》 SCIE EI CAS 2014年第6期1229-1244,共16页
We calculated and analyzed variation of the non-dipole(ND)magnetic field at the millennium scale over the Chinese mainland during 2000 BC–1900 AD using the newest global geomagnetic model,CALS3K.4(3K.4).The newest-ge... We calculated and analyzed variation of the non-dipole(ND)magnetic field at the millennium scale over the Chinese mainland during 2000 BC–1900 AD using the newest global geomagnetic model,CALS3K.4(3K.4).The newest-generation IGRF(IGRF11)was used to verify the results.Taking component Z for example,we calculated and analyzed the distribution and annual change rates of the ND field during 1900–1990 AD every 5 yr,using two models.To thoroughly analyze the contributions of field sources,quadrupole and octupole fields,and others within the ND field at the surface and core-mantle boundary(CMB)were investigated.Results show that there were three main variation phases of the field during the period 2000BC–1900 AD.The mean amplitude roughly reflected the ND field because of the distribution and variation of that field,corresponding somewhat to the mean amplitude change.A magnetic anomaly of the ND field over East Asia(EA)first emerged in 1682 AD,and its extreme intensity had increased a total of 15276.95 nT by 1900 AD.Its location moved continuously southeastward after 1690 AD.The asymmetry between location and intensity of extreme points over EA,particularly during1740–1760 AD,indicates irregularity of fluid motion inside the outer core.Mean annual changes of Z are generally divided into four phases,which first oscillated between 2000 and 800 BC,then increased,decreased and increased in the periods 800BC–300 AD,300–900 AD and 900–1900 AD,respectively.The intensity of mean annual change increased a total of 22.87nT/yr.Anomaly extreme locations based on 3K.4 and IGRF11 over EA centered around 44°N and 103°E for degree(n)greater than 5,and intensities continuously increased with n.During 2000 BC–1990 AD,ND energy of Z at the surface and CMB had decreased in total by 18.29%and 23.23%,respectively.The field source of 26–210 pole fields are more or less affected by the lithospheric field.Energies of higher degree at the surface attenuate by almost 99%compared with CMB,but mean attenuation speeds of the low-degree ND field are faster than high-degree,which implies that the low-degree ND field has a deeper source. 展开更多
关键词 non-dipole geomagnetic field CALS3K.4 IGRF11
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