Asian-Pacific Oscillation index and variation of East Asian summer monsoon over the past millennium

To study the long-term variation of the East Asian summer monsoon （EASM）, the Asian-Pacific Oscillation index （IAPO）, representing a zonal thermal contrast between Asia and the North Pacific, is reconstructed over the past millennium. During the Little Ice Age （LIA）, the variability of the reconstructed IAPO is closely linked to dry-wet anomalies in eastern China on the centennial scale. This correlation pattern is consistent with the observation during the current period, which suggests that the reconstructed IAPO may generally represent the centennial-scale variation of the EASM and rainfall anomalies over eastern China during the LIA.     

Inverse correlation between ancient winter and summer monsoons in East Asia？

There is a scientific debate on the relationship between ancient winter and summer monsoons in East Asia. Some scholars think that East Asian winter and summer monsoons are anti-correlated, and others think not. For this reason, this study is motivated to assess their linkage from the paleoclimate simulation perspective, through analyzing the Last Glacial Maximum （LGM） and mid-Holocene （MH） climate simulated by CCSM3 model. Compared to the present climate, the Aleutian low is found to be deepened and the East Asian winter monsoon （EAWM） is stronger during the LGM winter. The Pacific high in summer is noticed to be weakened and the East Asian summer monsoon （EASM） is weaker at the LGM. During the MH, the Aleutian low and the Asian high in winter are intensified, and the Asian low and the Pacific high in summer are enhanced, indicating that the EAWM and EASM are both stronger than today. Therefore, the EAWM is not always negatively correlated to the EASM. Their relationship may be different at different geological stages. It can be obtained at least from the numerical simulation results that the EAWM and the EASM is negatively correlated during the cooling period, while positively correlated during the warming period.     

京沪高速铁路无砟轨道夏季、雨季施工技术保证措施

京沪高速铁路无砟轨道施工中采用无砟轨道夏季、雨季施工技术，达到了预期的质量目标和进度目标。本文对其施工技术加以总结，旨在推广。     

中国西部岩画的研究方法探讨——以西南、青藏高原岩画研究为例

关于岩画的研究,每位研究者都不免受限于其所处时代及当时流行的学术观念,只能看到其力所能及之处。本文追述了西南及青藏高原岩画研究中各种不同的研究焦点和方法,进而探讨了西部岩画的研究方法。     

夏季桃树修剪技术

夏季桃树修剪主要针对生长旺盛的幼树、初结果树。修剪作用使其达到平衡树势，加速成形，达到早结果、早丰产的效果。夏季修剪次数以树龄、品种、树势和土壤条件而定，一般每年修剪3—4次。第一次修剪方法是抹芽除梢，矫正骨干枝；第二次修剪方法是控制竞争枝和徒长枝。调整枝的角度；第三次修剪方法是果枝、副梢摘心；第四修剪方法是控制二次副梢，促进花芽分化。     

浅议高层住宅建筑混凝土工程夏季施工过程的质量控制

混凝土工程作为高层建筑物竖向和水平方向承受荷载的主要部位,施工时若受到夏季气候变化的影响,对混凝土施工质量控制难度较大。本文将结合混凝土工程的施工过程,简要论述了混凝土夏季施工质量控制问题。     

青藏高原东缘30种禾本科植物种子萌发对光的响应及其与生活史的关联

在野外自然条件下设置三个不同光照强度的人工遮阴对青藏高原东缘30种不同生活型禾本科植物种子的萌发行为进行了研究.结果表明:各光照梯度下30种禾本科植物种子的萌发率差异不显著,平均萌发时间差异显著,外在环境因子光照主要影响植物种子萌发的进程.植物在存在竞争的环境中会选择快速萌发来争取幼苗茎杆伸长开始的时间,以截获更多的光...     

夏季不是断奶好时机

婴儿夏季勿断奶的三大理由 1、易患暑热综合征 夏季的气温升高，婴儿神经系统调节功能不能像正常成年人那样完善，较容易发生暑热，出现脱水症、中暑等情况。如果夏季婴儿仍采用母乳喂养，母乳会增强婴儿神经系统的调节功能，减少或避免以上病症的发生。