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    题名 作者 年代 出处 被引量
1ASTER数据在浅覆盖区蚀变遥感异常信息提取中的应用-以新疆西准噶尔包古图斑岩铜矿岩体为例显示文摘遥感卫星的多光谱数据应用于找矿已取得显著成效,2004年7月中国卫星地面站开始提供ASTER(Advanced Space-borne Thermal Emission and Reflection Radiometer,高级星载热发射反照辐射计)数据,因涵盖波长范围宽[VNIR(Visible and Near Infra-red)、SWIR(Short wave-length Infra-red)、TIR(Thermal Infra-red)]、波段多(14个波段)、性价比合理等因素,ASTER数据的研究迅速发展。长久以来,对覆盖区进行蚀变遥感异常信息提取一直是遥感找矿的关注点之一。笔者等利用ASTER数据对浅覆盖区——包古图斑岩铜矿的Ⅱ号、Ⅴ号斑岩体进行蚀变遥感异常提取,提取的蚀变异常与野外地质情况吻合性好。分别提取了光谱特征谱带差异明显的2组蚀变矿物的异常信息:第一组是蒙脱石、埃洛石、伊利石与绢云母;第二组是方解石、黑云母与绿泥石。提出了需要进一步工作的异常靶区。耿新霞 杨建民 张玉君 姚佛军 2008地质论评2008,54,2:81
2Tectonic thermal history and its significance on the formation of oil and gas accumulation and mineral deposit in Ordos Basin显示文摘The analyzing data on stratigraphic temperature measurement , thermal conductivity of the strata and radioactive heat production rate show that the present average geothermal gradient in the Ordos Basin is 2.93℃/100 m, and the average heat flow value is 61.78 mW/m2, which belongs to the mesothermal basin, and the value of the present geothermal gradient and heat flow in the east is higher than that in the west. The sandstone radioactive heat production rate of Zhiluo Group in Dongsheng Uranium deposits of Yimeng uplift is obviously higher in the mudstone, indicating that there exists a uranium anomaly. Based on studies of the present thermal field of the basin, the late-Mesozoic paleotemperature and paleogeothermal gradient are determined by using different kinds of paleotemperature methods. According to the anomaly of the late-Mesozoic paleotemperature gradient and magmatic event age, there was a tectonic thermal event in the early Cretaceous epoch of late-Mesozoic. This article rebuilds tectonic thermal history of different tectonic units by thermal history simulation using basin simulating software. The evolution of oil-gas and coal, and accumulation (mineralization) of mineral uranium are all controlled by the tectonic thermal history in the Ordos basin, especially by the tectonic thermal event that happened in the late Mesozoic. For both the gas source rocks of upper Paleozoic group and lower paleozoic group, the gas was largely generated in the early Cretaceous epoch of the late Mesozoic. The main petroleum generation period for Yanchang Group in Triassic system is the early Cretaceous epoch too, and the highest thermal maturity of the coal of Permo-Carboniferous, Triassic, and Jurassic reaches is the early Cretaceous epoch also. Early Cretaceous epoch is still one of the most important mineralizing periods of uranium.REN ZhanLi ZHANG Sheng GAO ShengLi CUI JunPing XIAO YuanYuan XIAO Hui 2007Science China Earth Sciences2007,50,z2:44
3Resection vs thermal ablation of small hepatocellular carcinoma:What's the first choice?显示文摘Nowadays,hepatocellular carcinoma(HCC) is frequently diagnosed at an early stage,opening good perspectives to radical treatment by means of liver transplantation,surgical resection,or percutaneous ablation.Liver transplantation is considered the best option,but the lack of liver donors represents a major limitation.Therefore,surgical resection,offering a 5-year-survival rate of over 50%,is considered the first-choice treatment for patients with early stage HCC,whereas percutaneous ablation is usually reserved to patients who are not candidate to surgery.However,in the recent years some trials showed that percutaneous radiofrequency ablation(RFA) can be as effective as surgical resection in terms of overall survival and recurrencefree survival rates in patients with small HCC,and a retrospective comparative study reported 1-,3-,and 5-year overall survival rates and recurrence-free survival rates significantly better in patients with central HCC measuring 2 cm or smaller treated with RFA than in those treated with surgical resection.RFA is less expensive,less invasive,with lower complication rate and shorter hospital stay than surgical resection,and on the basis of the results of these studies it should be considered the first option in the treatment of very early HCC.However,RFA is size-dependent,so at present the need to achieve an adequate safety margin around the tumor limits to about 2 cm the diameter of the nodules that can be ablated with long-term outcomes comparable to or better than surgical resection.The main goal of the next technical developments of the thermal ablation systems should be the achievement of larger ablation areas with a single needle insertion.In this regard,the recent improvements in microwave energy delivery systems seem to open interesting perspectives to percutaneous microwave ablation,which could become the ablation technique of choice in the next future.Paola Tombesi Francesca Di Vece Sergio Sartori 2013World Journal of Radiology2013,5,1:50
4造山带中成对出现的高压麻粒岩与榴辉岩及其地球动力学意义显示文摘在一些典型碰撞造山带中,高压麻粒岩与榴辉岩在空间和时间上密切相关,它们之间的关系对揭示碰撞造山带的造山过程和造山机制具有重要意义。本文以中国西部的南阿尔金、柴北缘及中部的北秦岭造山带为例,详细陈述了这3个地区榴辉岩和相关的高压麻粒岩的野外关系、变质演化和形成时代,目的是要建立大陆碰撞造山带中榴辉岩和相关高压麻粒岩形成的地球动力学背景模式。南阿尔金榴辉岩呈近东西向分布在江尕勒萨依-玉石矿沟一带,与含夕线石副片麻岩、花岗质片麻岩和少量大理岩构成榴辉岩-片麻岩单元,榴辉岩中含有柯石英假象,其峰期变质条件为P=2.8~3.0GPa,T=730~850℃,并在抬升过程中经历了角闪岩-麻粒岩相的叠加;大量年代学研究显示其峰期变质时代为485~500Ma。南阿尔金高压麻粒岩分布在巴什瓦克地区,包括高压基性麻粒岩和高压长英质麻粒岩,它们与超基性岩构成了一个大约5km宽的构造岩石单元,与周围角闪岩相的片麻岩为韧性剪切带接触。长英质麻粒岩和基性麻粒岩的峰期组合均具有蓝晶石和三元长石(已变成条纹长石),形成的温压条件为T=930~1020℃,P=1.8~2.5GPa,并在退变质过程中经历了中压麻粒岩相变质作用叠加。锆石SHRIMP测定显示巴什瓦克高压麻粒岩的峰期变质时代为493~497Ma。都兰地区的榴辉岩分布柴北缘HP-UHP变质带的东端,在榴辉岩和围岩副片麻岩中均发现有柯石英保存,形成的峰期温压条件为T=670~730℃和,P=2.7~3.25GPa,退变质阶段经过了角闪岩相的叠加;榴辉岩相变质时代为420~450Ma。都兰地区的高压麻粒岩分布在阿尔茨托山西部,高压麻粒岩包括基性麻粒岩长英质麻粒岩,基性麻粒岩的峰期矿物组合为Crt+Cpx+Pl±Ky±Zo+Rt±Qtz,长英质麻粒岩的峰期矿物组合为:Grt+Kf+Ky+Pl+Qtz。峰期变质条件为T=800~925℃,P=1.4~1.85GPa,退变质阶段经历了角闪岩-绿片岩的改造,高压麻粒岩的变质时代为420~450Ma。北秦岭榴辉岩分布在官坡-双槐树一带,榴辉岩的峰期变质组合为Grt+Omp±Phe+Qtz+Rt,所计算的峰期温压条件为T=680~770℃和P=2.25~2.65GPa,年代学数据显示榴辉岩的变质时代为500Ma左右。北秦岭高压麻粒岩分布在含榴辉岩单元的南侧松树沟一带,包括高压基性麻粒岩和高压长英质麻粒岩,与超基性岩在空间上密切伴生,高压麻粒岩的峰期温压条件为T=850~925℃,P=1.45~1.80GPa,锆石U-Pb年代学研究显示其峰期变质时代为485~507Ma。以上三个实例显示,出现在同一造山带、在空间上伴生的高压麻粒岩和榴辉岩有各自不同的变质演化历史,但榴辉岩中的榴辉岩相变质时代和相邻的高压麻粒岩中的高压麻粒岩相变质作用时代相同或相近,这种成对出现的榴辉岩和高压麻粒岩代表了它们同时形成在造山带中不同的构造环境中,即榴辉岩的形成于大陆俯冲带中,而高压麻粒岩可能形成在俯冲带之上增厚的大陆地壳根部。张建新 于胜尧 孟繁聪 李金平 2009岩石学报2009,25,9:46
5A temperature prediction-correction method for estimating surface soil heat flux from soil temperature and moisture data显示文摘Surface soil heat flux is a component of surface energy budget and its estimation is needed in land-atmosphere interaction studies. This paper develops a new simple method to estimate soil heat flux from soil temperature and moisture observations. It gives soil temperature profile with the thermal diffusion equation and, then, adjusts the temperature profile with differences between observed and computed soil temperatures. The soil flux is obtained through integrating the soil temperature profile. Compared with previous methods, the new method does not require accurate thermal conductivity. Case studies based on observations, synthetic data, and sensitivity analyses show that the new method is preferable and the results obtained with it are not sensitive to the availability of temperature data in the topsoil. In addition, we pointed out that the soil heat flux measured with a heat-plate can be quite erroneous in magnitude though its phase is accurate.Kun Yang JieMin Wang 2008Science China Earth Sciences2008,51,5:39
6Global warming weakening the inherent stability of glaciers and permafrost显示文摘The Cryosphere has been undergoing a worldwide retreat, as seen in the decrease in the areal extent and volume of glaciers and in the areal extent of permafrost. This paper presents a systematic examination of the inherent stability changes of glaciers and permafrost caused by warming. Various study results suggest that over the past 30 years, the internal temperature of glaciers and permafrost exhibits an overall accelerating warming trend. The warming rate peaked in the mid-2000s and slowed slightly for several years afterward. In recent years, however, the warming rate has seemed to pick up again. The warming of glaciers and permafrost has exerted great impact on their stability, displayed as intensified melting,increased glacier surging, enlargement of supraglacial lakes, and increased permafrost degradation.Even without a future temperature increase, some glaciers will continue to shrink, and the number of surging glaciers will increase. The transition from low-temperature to high-temperature permafrost is a noticeable warning sign of a comprehensive degradation of permafrost. These results indicate that‘‘warming' glaciers and permafrost will exert significant impacts on the hydrology, ecology, and stability of engineering in cold regions.Yongjian Ding Shiqiang Zhang Lin Zhao Zhongqin Li Shichang Kang 2019Science Bulletin2019,64,4:37
7Hydrocarbon sources and stages of reservoir formation in Kuqa depression, Tarim Basin显示文摘Kuqa depression bears not only plenty ofnatural gas, but also a large amount of condensate and smallquantity of crude oil. Based on the geochemical correlationbetween the Jurassic and Triassic terrestrial hydrocarbonsource rock, this paper confirms that the natural gas in Kuqadepression belongs to coal-type gas and the main gas sourcerock is attributed to the middle to lower Jurassic coal seriesformation, while the main oil source rock is the upper Tri-assic lacustrine mudstone. The authors indicated that Kuqadepression was slowly subsided in Mesozoic, but rapidlywent down in Late Tertiary, which made the Jurassic andTriassic source rock suddenly deep-buried and rapidlyevolved to high and over-mature phase since 5 Ma. TheTriassic source rock is postponed to the Early Miocene dur-ing 23-12 Ma when entering the oil-generating peak, whilethe Jurassic is suspended to the latest 5 Ma, especially since2.5 Ma to the dry gas-generating period, which is one of thecharacteristics of the source rock thermal evolution in Kuqadepression. This paper presents a two-stage trapping andlate gas trapping model in Kuqa depression whose charac-teristics are: The main oil and gas reservoirs have differentsources. The oil reservoir is formed early while the gas res-ervoir is formed lately. During the early stage, it, mainly asoil, takes long distance lateral migration, while in the laterstage, it, mainly as gas, takes the vertical migration and alsohas lateral migration. The trap formed in different time onthe south and north sides of the depression and evolved intoa distributional pattern with oil in the south part and gas inthe north, also oil on the outer ring and gas on the inner ring.This paper points out that the late trapping of the naturalgas in Kuqa depression is favorable for the preservation oflarge gas fields.LIANG Digang ZHANG Shuichang ZHAO Mengjun WANG Feiyu 2002Chinese Science Bulletin2002,47,S1:34
8High intensity focused ultrasound in clinical tumor ablation显示文摘Recent advances in high intensity focused ultrasound(HIFU),which was developed in the 1940s as a viable thermal tissue ablation approach,have increased its popularity.In clinics,HIFU has been applied to treat a variety of solid malignant tumors in a well-defined volume,including the pancreas,liver,prostate,breast,uterine fibroids,and soft-tissue sarcomas.In comparison to conventional tumor/cancer treatment modalities,such as open surgery,radio-and chemo-therapy,HIFU has the advantages of non-invasion,non-ionization,and fewer complications after treatment.Over 100 000 cases have been treated throughout the world with great success.The fundamental principles of HIFU ablation are coagulative thermal necrosis due to the absorption of ultrasound energy during transmission in tissue and the induced cavitation damage.This paper reviews the clinical outcomes of HIFU ablation for applicable cancers,and then summarizes the recommendations for a satisfactory HIFU treatment according to clinical experience.In addition,the current challenges in HIFU for engineers and physicians are also included.More recent horizons have broadened the application of HIFU in tumor treatment,such as HIFU-mediated drug delivery,vessel occlusion,and soft tissue erosion(“histotripsy”).In summary,HIFU is likely to play a significant role in the future oncology practice.Yu-Feng Zhou 2011World Journal of Clinical Oncology2011,2,1:33
9Recent advances in solid-state LED phosphors with thermally stable luminescence显示文摘Phosphor-converted white light-emitting diode(LED) lighting has gained tremendous achievements since the invention of the InGaN blue LED by Nakamura et al., who won the Nobel Physics Prize in 2014.By far, a significant challenge comes from the thermal quenching(TQ) behavior of the present LED phosphors during the high-power LED operation or the updated laser lighting. But systematic research or review on the luminescence quenching character and/or how to realize thermally stable luminescence are lacking. Since TQ is an inherent property of phosphors, it can be diminished by different approaches.This review proceeds from the mechanism of TQ, summarizes previous researches on improving the thermal stability of LED phosphors and also discusses future research opportunities in this field. The developments of the phosphors with properties of high luminance and thermal stability, as well as the improved strategies involved,will benefit the basic researches and applications in high power lighting or high-luminance laser lighting.Jianwei Qiao Jing Zhao Quanlin Liu Zhiguo Xia 2019Journal of Rare Earths2019,37,6:34
10Research on solar aided coal-fired power generation system and performance analysis显示文摘Integrating solar power utilization systems with coal-fired power units, the solar aided coal-fired power generation (SACPG) shows a significant prospect for the large-scale utilization of solar energy and energy saving of thermal power units. The methods and mechanism of system integration were studied. The parabolic trough solar collectors were used to collect solar energy and the integration scheme of SACPG system was determined considering the matching of working fluid flows and energy flows. The thermodynamic characteristics of solar thermal power generation and their effects on the performance of thermal power units were studied, and based on this the integration and optimization model of system structure and parameters were built up. The integration rules and coupling mecha- nism of SACPG systems were summarized in accordance with simulation results. The economic analysis of this SACPG system showed that the solar LEC of a typical SACPG system, considering CO2 avoidance, is 0.098 $/kW·h, lower than that of SEGS, 0.14 $/kW·h.YANG YongPing CUI YingHong HOU HongJuan GUO XiYan YANG ZhiPing WANG NinLing 2008Science China(Technological Sciences)2008,51,8:30
11Future changes in thermal comfort conditions over China based on multi-RegCM4 simulations显示文摘使用4个不同全球模式模拟结果,驱动RegCM4区域气候模式,进行了RCP4.5中等温室气体排放情景下东亚地区21世纪气候变化的高分辨率(25 km)模拟。本文基于此套模拟集合,使用综合考虑了气温、相对湿度和风速因素的人体热感受指数有效温度(ET),给出了未来中国区域热舒适条件的变化。分析中同时考虑了未来人口数量和分布情景所引起的暴露度变化。研究发现,未来中国区域的ET的普遍升高引起炎热天气的人口暴露度大幅度增加(到21世纪末相对于当代全国平均将增加6倍‘人-天’(person–days),凉、冷和寒冷天气的暴露度则减少。同时尽管舒适日数有所增加,但相应的人-天数目则有22%的减少。不同因素(气候、人口和两者的相互作用)对于上述变化的贡献分析表明,在舒适度的热端,气候因素的作用更重要,而人口因素则在冷端起着主导作用。总体而言,即使是在中等水平温室气体排放情景下,中国区域未来的热强度也将增加,尽管结果表现出很强的地理依赖特征。相对使用单纯气候因素的结果,人口暴露度的引入对变化信号有着强烈的调制作用,从而更加强调了在与气候变化相关的风险评估分析中,考虑社会-经济因素的重要性。GAO Xue-Jie WU Jie SHI Ying WU Jia HAN Zhen-Yu ZHANG Dong-Feng TONG Yao LI Rou-Ke XU Ying GIORGI Filippo 2018Atmospheric and Oceanic Science Letters2018,11,4:30
12Hydrogen isotope composition of natural gases from the Tarim Basin and its indication of depositional environments of the source rocks显示文摘By measuring carbon and hydrogen isotope compositions for C1, C2 and C3 of 74 gas samples, natural gases from the Tarim Basin can be divided into six groups on the basis of their origins: (1) coal-type gas derived from coal measures; (2) coal-type gas generated from the T-J lacustrine mudstones; (3) oil-type gas derived from the Cambrian and low Ordovician marine source rocks; (4) oil-type gas from the source rocks deposited in the marine-transitional facies; (5) mixing gas between gas derived from the Carboniferous transitional source rocks and the Mesozoic humic gas, and (6) mixing gases of thermal genetic gas and little deep gas in the Southwest depression of the Tarim Basin. The δ D values of methane in natural gases originating from different type kerogens are affected by both palaeo-environments of the source rock formation (kerogen types) and thermal maturity, with sedimentary environment (kerogen type) as the main controlling factor. Under the similar thermal maturity, the hydrogen isotope composition of methane is more enriched in deuterium in marine environments than lacustrine one. With the increase of thermal maturity and the increase of carbon atomic numbers of gaseous alkanes, the hydrogen isotopes become enriched in deuterium. The δ D values of ethane and propane (δ D2, δ D3) are controlled mainly by thermal maturity and to a lesser degree by sedimentary environment of the source rock formation. The partial reversal of hydrogen isotopes for gaseous alkanes would be related to the microbial oxidation, mixing of sapropelic and humic gases and / or mixing of gases from similar kerogen sources with various thermal maturities. In the oil-type gas, the sulfate reduction reaction would result in the reversed order of δ D1 and δ D2 (e.g. δ D1>δ D2).LIU QuanYou DAI JinXing LI Jian ZHOU QingHua 2008Science China Earth Sciences2008,51,2:28
13NUMERICAL SIMULATION OF ROUND TO OVAL ROLLING PROCESS显示文摘Three dimensional thermal-mechanical coupled elasto-plastic FEM has been used for simulation of round to oval single pass rolling. The analysis was conducted using MARC/AUTOFORCE1. 2 code. The material is assumed to be elasto-plastic and it obey the Von Mises yield criterion and Prandtl- Reuss rule. Deformation of the workpiece is simulated in a step-by-step manner,updating the coordinates of material points and the property after each step, so that both nonsteady-state and stendy-state deformation can be simulated. The heat transfter between the workpiece, the rolls, and enviroment and the heat generation due to plastic work and friction force, are considered in the analys- is.Predicted the deformation shape of the workpiece, distributions of strains, stresses, strain rates and temperatures, roll-separating force and roll torque are presented.Y. W. Wang, Y. L. King, D. H. Yuan, S. G. Liu and Z. Y. Yu 1 ) University of Science and Technology Beijing, Beijing 100083, China 2) Daye Special Steel Co., Huangshi 435001, China 2000Acta Metallurgica Sinica(English Letters)2000,13,2:27
14A New Potential Function With Many-Atom Interactions in Solid显示文摘Based on the many-atom interaction model and valence bond theory of metals, a new potential function for the interaction among atoms in solid is proposed in the present work. Because the reduced bond length is taken as variable, the new potential function can be simplified to have the form analogous to the Lennard-Jones potential. Accoroding to Debye model, a series of equations for calculating various elasticities and constants K and Q in Gruneisen equation have been derived from the new potential function. The application of the new potential function to Ni, Cu and five alkli metals shows that these equations are correct.谢佑卿 1993Science China Mathematics1993,36,1:27
15Microwave ablation of hepatocellular carcinoma显示文摘Although surgical resection is still the optimal treatment option for early-stage hepatocellular carcinoma(HCC) in patients with well compensated cirrhosis,thermal ablation techniques provide a valid nonsurgical treatment alternative,thanks to their minimal invasiveness,excellent tolerability and safety profile,proven efficacy in local disease control,virtually unlimited repeatability and cost-effectiveness.Different energy sources are currently employed in clinics as physical agents for percutaneous or intra-surgical thermal ablation of HCC nodules.Among them,radiofrequency(RF) currents are the most used,while microwave ablations(MWA) are becoming increasingly popular.Starting from the 90s',RF ablation(RFA) rapidly became the standard of care in ablation,especially in the treatment of small HCC nodules;however,RFA exhibits substantial performance limitations in the treatment of large lesions and/or tumors located near major heat sinks.MWA,first introduced in the Far Eastern clinical practice in the 80s',showing promising results but also severe limitations in the controllability of the emitted field and in the high amount of power employed for the ablation of large tumors,resulting in a poor coagulative performance and a relatively high complication rate,nowadays shows better results both in terms of treatment controllability and of overall coagulative performance,thanks to the improvement of technology.In this review we provide an extensive and detailed overview of the key physical and technical aspects of MWA and of the currently available systems,and we want to discuss the most relevant published data on MWA treatments of HCC nodules in regard to clinical results and to the type and rate of complications,both in absolute terms and in comparison with RFA.Guido Poggi Nevio Tosoratti Benedetta Montagna Chiara Picchi 2015World Journal of Hepatology2015,7,25:28
16Temperature effect and thermal impact in lithium-ion batteries: A review显示文摘Lithium-ion batteries, with high energy density(up to 705 Wh/L) and power density(up to 10,000 W/L), exhibit high capacity and great working performance. As rechargeable batteries, lithium-ion batteries serve as power sources in various application systems. Temperature, as a critical factor, significantly impacts on the performance of lithium-ion batteries and also limits the application of lithium-ion batteries. Moreover, different temperature conditions result in different adverse effects. Accurate measurement of temperature inside lithiumion batteries and understanding the temperature effects are important for the proper battery management. In this review, we discuss the effects of temperature to lithium-ion batteries at both low and high temperature ranges.The current approaches in monitoring the internal temperature of lithium-ion batteries via both contact and contactless processes are also discussed in the review.Shuai Ma Modi Jiang Peng Tao Chengyi Song Jianbo Wu Jun Wang Tao Deng Wen Shang 2018Progress in Natural Science:Materials International2018,28,6:27
17A comprehensive physical pattern of land-air dynamic and thermal structure on the Qinghai-Xizang Plateau显示文摘According to the boundary layer observations of three stations (Garze, Damxung and Qamdu) and relevant earth satellite, radiosonde and surface observations during the intensive observational period (IOP) of the second Tibetan (Qinghai-Xizang) Plateau Experiment of atmospheric science (TIPEX), the land-air physical process and dynamic model on the Tibetan Plateau were comprehensively analyzed in this study. The dynamic characteristics of boundary layer and the rules of turbulent motion on the plateau were illustrated. The characteristics of distributions of wind speed and direction with mutiple-layer structure and deep convective mixed layer on the plateau, the strong buoyancy effect in turbulent motion on the plateau on which the air density is obviously smaller than on the plain, and the Ekman spiral and its dynamic pump effect of the plateau deep boundary layer have been found. The local static distribution of water vapor and the horizontal advection of water vapor in the plateau boundary layer were studied. The abnomal thermodynamic structure on the plateau surface and boundary layer, including the plateau strong radiation phenomenon and strong heating source characteristics of the middle plateau, was also analyzed. The authors synthesized the above dynamic and thermodynamic structures of both surface and boundary layers on the plateau and posed the comprehensive physical model of the turbulence and convective mixture mechanism on the plateau boundary layer. The characteristics of formation, development and movement for convective cloud cluster over the plateau influencing floods in the Yangtze River area of China were studied. The conceptual model of dynamic and thermodynamic structures of turbulent motion and convective plume related to the frequent occurrence of 'pop-corn-like' cloud system is given as well.徐祥德 卞林根 李诗明 索朗多吉 周明煜 张光智 张宏升 王继志 陈家宜 刘辉志 赵翼俊 2002Science China Earth Sciences2002,45,7:24
18秦岭岩群中两类斜长角闪岩的性质和时代及其地质意义显示文摘在北秦岭造山带核部秦岭岩群内发育两类不同产状的斜长角闪岩。一类与秦岭岩群中的大理岩紧密共生,呈规模较大的似层状或较小块体产于大理岩内,另一类则呈密集岩墙群型式侵入于秦岭岩群南段二云母石英片岩中。不同的产出状态表明两类斜长角闪岩的成因和时代存在显著差异,也具有不同的地质构造意义。地球化学上,两类不同产状的斜长角闪岩的原岩皆为玄武岩质的。侵入秦岭岩群二云母石英片岩中的斜长角闪岩墙群形成于板内拉张环境,SHRIMP锆石U-Pb测年揭示该类斜长角闪岩形成于晚奥陶世(449±11Ma),Sr-Nd同位素特征显示其岩浆源区为亏损地幔源区,^(40)Ar/^(39)Ar热年代学研究显示该类斜长角闪岩的角闪岩相变质作用发生于石炭纪末期(301.3±6.4Ma)。地球化学和Sr-Nd同位素特征显示与秦岭岩群大理岩共生的似层状或块状斜长角闪岩的形成环境与侵入云母石英片岩中的斜长角闪岩墙群的存在显著差异,其形成于洋岛(OIB)或海山环境。^(40)Ar/^(39)Ar热年代学研究显示该类斜长角闪岩于晚二叠世(258.1±5.7Ma)发生了角闪岩相变质作用。不同性质、形成和变质时代、相似的变质作用等特点表明,秦岭岩群中的两类角闪岩分属不同性质的构造块体,秦岭岩群高级变地质地体可能是一个构造拼合地体。斜长角闪岩岩墙为晚奥陶世(449±11Ma)侵入秦岭岩群云英片岩中的基性岩墙群,是北秦岭晚加里东期后造山期热收缩而致的地壳伸展或岩圈拆离减薄的产物。与秦岭岩群大理岩共生的斜长角闪岩则可能是洋隆体的基性喷出岩+碳酸盐岩帽组合,是中二叠世(312~260Ma)期间构造移置而来的外来块体。闫全人 王宗起 闫臻 陈隽璐 向忠金 王涛 张宏远 2009岩石学报2009,25,9:24
19Constraining the stepwise migration of the eastern Tibetan Plateau margin by apatite fission track thermochronology显示文摘Granites sampled from Garzê-Litang thrust, Longmen Shan thrust, Garzê and Litang strike-slip faults in the eastern Tibetan Plateau have been analyzed with apatite fission track thermochronological method in this study. The measured fission track apparent ages, combined with the simulated annealing mod- eling of the thermal history, have been used to reconstruct the thermal evolutionary histories of the samples and interpret the active history of the thrusts and faults in these areas. Thermal history mod- eling shows that earlier tectonic cooling occurred in the Garzê-Litang thrust in Miocene (~20―16 Ma) whereas the later cooling occurred mainly in the Longmen Shan thrust since ~5 Ma. Our study sug- gests that the margin of eastern Tibetan Plateau was extended by stages: through strike-slip faults deformations and related thrusts, the upper crust formed the Garzê-Litang margin in the Miocene epoch and then moved to the Longmen Shan margin since ~5 Ma. During this process, the deformations of different phases in the eastern Tibetan Plateau were absorbed by the thrusts within them and conse- quently the tectonic events of long-distance slip and extrusion up to hundreds of kilometers have not been found.LAI QingZhou DING Lin WANG HongWei YUE YaHui CAI FuLong 2007Science China Earth Sciences2007,50,2:24
20Advances on strategies for searching for next generation thermal barrier coating materials显示文摘Thermal barrier coating(TBC) materials play important roles in gas turbine engines to protect the Nibased super-alloys from the high temperature airflow damage. High melting point, ultra-low thermal conductivity, large thermal expansion coefficient, excellent damage tolerance and moderate mechanical properties are the main requirements of promising TBC materials. In order to improve the efficiency of jet and/or gas turbine engines, which is the key of improved thrust-to-weight ratios and the energysaving, significant efforts have been made on searching for enhanced TBC materials. Theoretically, density functional theory has been successfully used in scanning the structure and properties of materials, and at the same time predicting the mechanical and thermal properties of promising TBC materials for high and ultrahigh temperature applications, which are validated by subsequent experiments. Experimentally,doping and/or alloying are also widely applied to further decrease their thermal conductivities. Now, the strategy through combining theoretical calculations and experiments on searching for next generation thermal insulator materials is widely adopted. In this review, the common used techniques and the recent advantages on searching for promising TBC materials in both theory and experiments are summarized.Bin Liu Yuchen Liu Changhua Zhu Huimin Xiang Hongfei Chen Luchao Sun Yanfeng Gao Yanchun Zhou 2019Journal of Materials Science & Technology2019,35,5:24
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