中国20年一遇气温和降水极值变化的高分辨率模拟

基于25 km高分辨率区域气候模式（RegCM3）嵌套MIROC3.2_hires全球气候模式结果,进行IPCC SRES A1B情景下21世纪气候变化的模拟,分析中国区域未来气温和降水极值重现期的变化。首先检验模式对当代（1981-2000年）极端事件重现期的模拟能力,结果表明,模式能够较好地再现中国地区20年一遇极端事件的基本分布型,但所模拟的数值与观测相比还有一定偏差,特别是在极端降水方面。21世纪中期（2041-2060年）和末期（2081-2100年）20年一遇的高温极值在整个区域内均将升高,东北地区增幅最大;低温极值将增大,中心位于内蒙古、新疆及青藏高原南麓;降水极值也将普遍增大。气温和降水极值在21世纪末期的增加幅度均比中期要大。在未来全球变暖背景下,中国地区极端高温事件将明显增多,面积增大;极端低温事件将大幅度减少,面积减少;强降水事件也将增多,面积不断扩大。     

过去千年中国不同区域干湿的多尺度变化特征评估

依据近年发表的新成果,对中国过去千年干湿的年至百年尺度变化特征进行了总结梳理与对比分析,综合评估了20世纪干湿变幅的历史地位。主要结论是：① 根据历史文献记载重建的东中部各区干湿序列在1400年以后均达高信度,但其前因存在记录缺失,仅有半数时段的重建结果达高信度。在东北及内蒙古东部,根据不同地点湖沼沉积物记录揭示的区域干湿百年尺度变化特征在多数时段不一致。在西部的黄土高原、河西走廊、新疆中北部、青藏高原东北部和东南部等地区,利用不同地点树轮资料重建的干湿序列显示的干湿变化特征在区内一致性高。② 过去千年中国各地干湿变化均存在显著的年际、年代际和百年尺度周期。其中准2.5 a、60~80 a和110~120 a等尺度的周期为所有地区共有;3.5~5.0 a、20~35 a等尺度周期则主要发生在东北、东中部地区、黄土高原和青藏高原;而准45 a周期则只发生在东北和东中部地区（均超过90%信度水平）;各区域间的干湿变化位相并不同步。③ 尽管已发现青藏高原东北部20世纪很可能是过去3000 a最湿的世纪之一,但其他大多数区域的重建结果显示：20世纪的干湿变幅在年代际尺度上均未超出其前各个时段的变率范围。     

非节肢类海洋无脊椎动物中蜕皮甾体及其功能研究

非节肢类海洋无脊椎动物的许多物种中都发现有蜕皮甾体的存在,且存在形式多样,但目前对其确切来源、生物体内的合成或加工途径仍缺乏足够的了解,在生长发育、生殖活动及其他生理功能中如何发挥作用也需要进一步研究。分子生物学和全基因组测序的发展为蜕皮甾体合成途径重要酶类及蜕皮激素信号传导所需受体研究提供了更多的信息,以帮助科学家逐步阐明相关机制。     

RD20Ⅱ型钻机及空气潜孔锤钻进施工中若干问题探讨

采用RD20Ⅱ型钻机及空气潜孔锤钻进工艺,有效地解决了大口径煤层气孔、矿井通风孔、电缆孔及水源井等钻探施工中硬岩钻进效率低,干旱缺水地区钻探成本高,地层遇水易坍塌、缩径等问题。在介绍了RD20Ⅱ型钻机和QL系列潜孔锤结构特点的基础上,总结了在空气潜孔锤钻进中的一些问题及解决思路和措施。     

文山铝土矿A12O3测试中半二甲酚橙的作用

一水硬铝石及含刚玉（A12O3）铝土矿的测试较困难。NaF置换滴定法以二甲酚橙及半二甲酚橙较敏锐。可用半二甲酚橙（变色酸度在PH=5～6）直接调节酸度,再用作滴定的指示剂,效果较好。     

Slip distribution and source parameters of the 20 July 2017 Bodrum-Kos earthquake (Mw6.6) from GPS observations

Greek-Turkish boundary near the cities Kos and Bodrum has been shaken on July 20, 2017 by a Mw6.6 earthquake. The mainshock is located offshore and did not generate an on-land surface rupture. Analyzing pre- and post-earthquake continuous/survey-type static GPS observations, we investigated co-seismic surface displacements at 20 sites to characterize source parameters and slip-distribution of the mainshock. Fault plane solutions as well as co-seismic slip distribution have been acquired through the inversion of co-seismic GPS displacements modeling the event as elastic dislocations in a half space. Fault plane solution shows a southward dipping normal-type fault segment extending a depth down to ~12 km, which remains within the brittle upper crust. Results from the distributed slip inversion show that the mainshock activated a ~65 km fault section, which has three high slip patches, namely western, central and eastern patches, where the coseismic slips reach up to 13, 26, and 5 cm, respectively. This slip pattern indicates that the pre-earthquake coupling, which is storing the slip deficit, occurred on these three patches.     

Surface Air Temperature Projection Under 1.5 ℃ Warming Threshold Based on Corrected Pattern Scaling Technique

The global mean temperature during the recent decade (2007-2016) has increased above 1 ℃ relative to the pre-industrial period (1861-1890). The climate change and impact under 1.5 ℃ warming in the future have become a great concern in global society. Temperature projections, especially in regional scale, show great uncertainty depending on used climate models. Taking advantage of pattern scaling technique and observed temperature changes during 1951-2005, we tried to project the temperature changes globally under 1.5 ℃ threshold relative to current climate state, i.e. about 1 ℃ warming around 2007-2016. The projections of 21 climate models from the Coupled Model Intercomparison Project - Phase 5 under four Representative Concentration Pathways (RCP2.6, RC4.5, RCP6.0 and RCP8.5) were used to correct the assumptions in pattern scaling. Results showed that the geographical distribution and warming amplitude of surface air temperature changes under 1.5 ℃ threshold are similar in the four scenarios. Warming over most of the land would be above 0.6 ℃, 0.3 ℃ warmer than ocean. The Northern Hemisphere would be 0.2 ℃ warmer than the Southern Hemisphere. The temperature over China region will increase by 0.7 ℃. The warming in the Northern and Central China under RCP2.6 was obviously higher than that in the other scenarios. Ignoring the impact of correction method, uncertainty in temperature projection based on pattern scaling was much smaller than that in climate models, both in global and regional scales.     

Mineral chemistry of a Cenozoic igneous complex,the Urumieh–Dokhtar magmatic belt,Iran: Petrological implications for the plutonic rocks

The Niyasar plutonic complex, one of the Cenozoic magmatic assemblages in the Urumieh‐Dokhtar magmatic belt, was the subject of detailed petrographic and mineralogical investigations. The Niyasar magmatic complex is composed of Eocene to Oligocene mafic rocks and Miocene granitoids. Eleven samples, representing the major rock units in the Niyasar magmatic complex and contact aureole were chosen for mineral chemical studies and for estimation of the pressure, temperature, and oxygen fugacity conditions of mineral crystallization during emplacement of various magmatic bodies. The analyzed samples are composed of varying proportions of quartz, plagioclase, K‐feldspar, hornblende, biotite, titanite, magnetite, apatite, zircon, garnet, and clinopyroxene. Application of the Al‐in‐hornblende barometer indicates pressures of around 0.2 to 0.4 kbar for the Eocene–Oligocene mafic bodies and around 0.5 to 1.7 kbar for the Miocene granitoids. Hornblende‐plagioclase thermometry yields relatively low temperatures (661–780 °C), which probably reflect late stage re‐equilibration of these minerals. The assemblage titanite–magnetite–quartz as well as hornblende composition were used to constrain the oxygen fugacity and H₂O content during the crystallization of the parent magmas in the Miocene plutons. The results show that the Miocene granitoids crystallized from magmas with relatively high oxygen fugacity and high H₂O content (~5 wt% H₂O). The Miocene granitoids show similar range of oxygen fugacity, H₂O contents and mineral chemical compositions, which indicate a common source for their magmas. Although the crystallization pressures of the Miocene plutons discriminate various categories of plutonic bodies emplaced at depths of about 5.7–6.5 km (Marfioun pluton), about 4.2 km (Ghalhar pluton) and 1.9–2.3 km (Poudalg pluton), they were later uplifted to the same level by vertical displacement of faults. The emplacement depths of the Niyasar plutons suggest that the central part of the Urumieh‐Dokhtar magmatic belt has experienced an uplift rate of ca. 0.25–0.4 mm/yr from the Miocene onwards.     

西藏扎北盐湖秋季卤水(硫酸钠亚型)5℃等温蒸发实验研究

西藏扎北盐湖硫酸钠亚型卤水中富含元素Li、B、K和微量元素Rb、Cs等.为了更好地了解卤水在自然条件下的蒸发结晶规律,需对相应卤水进行低温室内等温蒸发实验研究.本文对该盐湖卤水进行了5℃等温蒸发试验,并利用Na+、K+、Mg2+//Cl-、SO42--H2O五元水盐体系0℃相图,构筑了从干基立体图Na2SO4角顶的放射...     

艾比湖最近20Ka的氧碳同位素记录与气候突变

本文根据新疆艾比湖ＺＫｏｏＢ孔中３０个氧碳同位素样品的测试数据，制作了艾比湖最近二万年来的氧碳同位素变化曲线，氧碳同位素记录的研究表明，最近二万年来艾比湖的δ＾１８Ｏ变化主要是受湖水的蒸发作用和淡化过程所控制，艾比湖的水体环境在最近二万年中至少经历了八次明显的波动变化，δ＾１８Ｏ变化所反映的环境演变过程与全球性气候变化基本一致。二万年来δ＾１３Ｃ值的波动主要受湖泊水体中ＴＤＩＣ变化以及湖泊水体与大