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基于背景噪声反演华南块体岩石圈三维S波速度结构

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北京大学学报（自然科学版） 2024年第3期60卷 442-452页

作者：吕杰陈永顺郭震北京大学地球与空间科学学院北京100871 南方科技大学海洋科学与工程系深圳518055

利用背景噪声方法,对布设在华南块体及其周边区域数个流动地震台阵中共704个地震台站的连续数据进行分析,反演得到华南岩石圈的三维S波速度结构。结果表明,地表附近S波速度结构与华南块体的地表构造高度相关,低速异常区集中在四川盆地... 详细信息

利用背景噪声方法,对布设在华南块体及其周边区域数个流动地震台阵中共704个地震台站的连续数据进行分析,反演得到华南岩石圈的三维S波速度结构。结果表明,地表附近S波速度结构与华南块体的地表构造高度相关,低速异常区集中在四川盆地和江汉盆地等沉积层较厚的区域。江南造山带的中上地壳呈现明显的高速异常,该高速异常即为华夏块体与扬子块体的分界区域。华夏块体中地壳低速异常区与该区域广泛分布的中生代花岗岩对应较好。华南上地幔岩石圈的东部与西部存在显著的速度差异,西部呈现显著的高速异常,反映西部四川盆地底部稳固的克拉通结构;上地幔的低速异常揭示华南东部岩石圈因太平洋板块俯冲的影响而明显减薄(<70km)。推测华夏块体以琼州海峡为中心的上地幔显著低速区可能对应海南地幔柱的热物质上涌。

关键词：华南块体 S波速度结构江南造山带板块俯冲

unveiling a novel metal-to-metal transition in luH_(2):Critically challenging superconductivity claims in lutetium hydrides

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Matter and Radiation at Extremes 2024年第3期9卷 65-73页

作者： Dong Wang Ningning Wang Caoshun Zhang Chunsheng Xia Weicheng Guo Xia Yin Kejun Bu Takeshi Nakagawa Jianbo Zhang Federico Gorelli Philip Dalladay-Simpson Thomas Meier Xujie lü liling Sun Jinguang Cheng Qiaoshi Zeng Yang Ding Ho-kwang Mao Center for High-Pressure Science and Technology Advanced Research Beijing 100094China Beijing National laboratory for Condensed Matter Physics and Institute of Physics Chinese Academy of SciencesBeijing 100190China Shanghai Key laboratory of Material Frontiers Research in Extreme Environments(MFree) Shanghai Advanced Research in Physical Sciences(SHARPS)Shanghai 201203China

Following the recent report by Dasenbrock-Gammon et al.[Nature 615,244–250(2023)]of near-ambient superconductivity in nitrogendoped lutetium trihydride(luH_(3-δ)N_(ε)),significant debate has emerged surrounding the composition and interpretation of the observed sharp resistance ***,we meticul.usly revisit these claims through comprehensive characterization and *** definitively identify the reported material as lutetium dihydride(luH_(2)),resolving the ambiguity surrounding its *** similar conditions(270–295 K and 1–2 GPa),we replicate the reported sharp decrease in electrical resistance with a 30%success rate,aligning with the observations by Dasenbrock-Gammon et ***,our extensive investigations reveal this phenomenon to be a novel pressure-induced metal-to-metal transition intrinsic to luH_(2),distinct from ***,nitrogen doping exerts minimal impact on this *** work not only elucidates the fundamental properties of luH_(2)andluH_(3),but also critically challenges the notion of superconductivity in these lutetium hydride *** findings pave the way for future research on lutetium hydride systems,while emphasizing the crucial importance of rigorous verification in claims of ambient-temperature superconductivity.

关键词： resistance hydride superconductivity

To treat or not to treat Alzheimer’s disease by the ketogenic diet? That is the question

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Neural Regeneration Research 2020年第5期15卷 857-858页

作者： Marzena ulamek-Koziol Ryszard Pluta laboratory of Ischemic and Neurodegenerative Brain Research Mossakowski Medical Research CentrePolish Academy of SciencesWarsawPoland First Department of Neurology Institute of Psychiatry and NeurologyWarsawPoland

Alzheimer’s disease (AD) and current treatments: AD is a serious neurological disorder worldwide that affects about 26 million people,and whose prevalence has been cal.ulated to quadruple by 2050,thus reaching over 1% of the total population,with the highest prevalence occurring in both adults and elderly (Pluta et al.,2018).Neurodegenerative processes of the sporadic form of AD probably start 20 years before the clinical onset of the disorder (Pluta et al.,2018).This disease is the most important cause of dementia in world aged society (~75%).AD is a disorder that affects not only patients but also their *** social and economic burden associated with AD was cal.ulated as an example in the united States alone;600 billion dollars annually is spent on caring for AD patients (Pluta et al.,2018).AD is the one of the great health-care challenges of the 21st *** incidence of AD,a chronic and progressive neurodegenerative disorder,is increasing,as well as the need for efficient methods of diagnosis,prevention and treatment (Pluta et al.,2018).The characteristic clinical and neuropathological hallmarks of AD are: dementia as the main clinical symptom and in post-mortem neuropathological examination,the presence of amyloid plaques as well as neurofibrillary tangles and loss of neurons in the brain of AD *** role of amyloid and tau protein is questioned in the etiology of AD and other causes such as ischemic etiology are being considered (Pluta and u?amek-Kozio?,2019).There are several treatments that are not causal but symptomatic that are not effective,especially for advanced *** date,only a few drugs are approved,such as acetylcholinesterase inhibitors and *** that regulate partly the activity of neurotransmitters and partly alleviate behavioral *** treatment options include active and passive immunization,anti-aggregation specifics,and secretase *** road to clarity AD etiology,early final ante mortem dia

关键词： diagnosis Alzheimer prevention protein vitamin or cause has

Hybrid uncertainties-based analysis and optimization design of powertrain mounting systems

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Science China(Technological Sciences) 2020年第5期63卷 838-850页

作者： CAI BoHao SHANGGuAN Wen-Bin lÜHui BO Tao School of Mechanical and Automotive Engineering South China University of TechnologyGuangzhou 510641China

In this study,a hybrid uncertainties-based analysis and optimization method is presented for the designs of the powertrain mounting system(PMS)involving mixed *** the presented method,the PMS parameters with sufficient data are treated as random variables,while those with limited information are defined as interval ***,an uncertainty-based analysis method called as hybrid interval-random perturbation-central difference method(HIRP-CDM),is proposed to compute the hybrid interval-random outputs of the inherent characteristics of the PMS in concerned *** addition,the hybrid interval-random-Monte Carlo method(HIR-MCM)is developed to verify the computational accuracy of ***,an optimization model mixed uncertainties is built up for the PMS design based on HIRP-CDM,in which the hybrid intervalrandom outputs of the concerned inherent characteristics are adopted to construct the design objective and *** complex optimization problem can be effectively settled by means of *** effectiveness of the presented method is verified by a numerical example.

关键词： powertrain mounting system hybrid uncertainties uncertainty analysis optimization design

long-Term Application of Organic Manure and Mineral Fertilizer on N_2O and CO_2 Emissions in a Red Soil from Cultivated Maize-Wheat Rotation in China

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Agricul.ural Sciences in China 2011年第11期10卷 1748-1757页

作者： ZHAI li-mei l.u Hong-bin ZHANG Ji-zong HuANG Jing WANG Bo-ren Key laboratory of Nonpoint Pol.ution Control Ministry of Agriculture~Institute of Agricultural Resources and Regional Planning ChineseAcademy of Agricultural Sciences Beijing 100081 P.R.China

A long-term field experiment was established to determine the influence of mineral fertilizer and organic manure on soil fertility. A tract of red soil （Ferralic Cambisol） in Qiyang Red Soil Experimental Station （Qiyang County, Hunan Province, China） was fertilized beginning in 1990 and N20 and CO2 were examined during the maize and wheat growth season of 2007-2008. The study involved five treatments： organic manure （NPKM）, fertilizer NPK （NPK）, fertilizer NP （NP）, fertilizer NK （NK）, and control （CK）. Manured soils had higher crop biomass, organic C, and pH than soils receiving the various mineralized fertilizers indicating that long-term application of manures could efficiently prevent red soil acidification and increase crop productivity. The application of manures and fertilizers at a rate of 300 kg N ha-1 yr-1 obviously increased NzO and CO2 emissions from 0.58 kg N20-N ha-~ yr-~ and 10565 kg C ha-~ yr-~ in the CK treatment soil to 3.0l kg N20-N ha-~ yr-~ and 28 663 kg C ha-~ yr-I in the NPKM treatment. There were also obvious different effects on N20 and CO2 emissions between applying fertilizer and manure. More N20 and CO2 released during the 184-d maize growing season than the 125- d wheat growth season in the manure fertilized soils but not in mineral fertilizer treatments. N20 emission was significantly affected by soil moisture only during the wheat growing season, and CO2 emission was affected by soil temperature only in CK and NP treatment during the wheat and maize growing season. In sum, this study indicates the application of organic manure may be a preferred strategy for maintaining red emissions than treatments only with mineral fertilizer. soil productivity, but may result in greater N20 and CO2

关键词： red soil N fertilizer organic manure temperature WFPS

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桩的模糊随机可靠性分析

岩土力学 2008年第7期29卷 1993-1996页

作者：吕玺琳吕龙吕恩琳同济大学地下建筑与工程系上海200092 西南交通大学峨嵋校区土木工程系四川峨嵋山614202 重庆大学工程力学系重庆400030

利用一次二阶矩法,考虑可靠性分析模型中随机参数的模糊性,建立了模糊随机可靠性分析模型。利用分解定理,取一系列λ截集,将模糊数转换为一系列区间数进行运算,得到了一种模糊随机可靠度的计算方法。将该法应用到桩的可靠性分析中,实例... 详细信息

利用一次二阶矩法,考虑可靠性分析模型中随机参数的模糊性,建立了模糊随机可靠性分析模型。利用分解定理,取一系列λ截集,将模糊数转换为一系列区间数进行运算,得到了一种模糊随机可靠度的计算方法。将该法应用到桩的可靠性分析中,实例表明,该方法是合理实用的。

关键词：一次二阶矩法模糊随机可靠度 λ截集区间数桩

Matrix Methods for Analysing Optical Resonators

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光电子.激光 1989年第2期 93-95页

作者： l.u|¨) BaidaDepartment of physics,Sichuan university, Chengdu,Tel. 55411-962

This paper deals with the applications of matrix methods to optical resonators. It has been shown that the important characteristics of resonators i.e.,mode characteristic parameters, misalignment sensitivity,condition for dynamic stability etc, can be expressed in terms of ABCD-matrix elements or resonator g parameters in general, some typicalresonators are analysed in detail。

关键词： Matrix Methods for Analysing Optical Resonators mode

A good surgical option for ischemic mitral regurgitation in co-morbid patients: semicircular reduction annuloplasty

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Journal of Geriatric Cardiology 2013年第2期10卷 141-145页

作者： Bilgin Emrecan Gokhan Onem Ahmet Coskun Ozdemir smail Do u K l Yusuf zzettin Alihano lu Department of Cardiac and Vascular Surgery Pamukkale University Kn klDenizli 20070 Turkey Department of Cardiac and Vascular surgery Denizli Cerrahi Hastanesi Acipayam yolu 5 Ba baDenizli 20225 Turkey Department of Cardiology Pamukkale University K n klDenizli 20070 Turkey

Background Ring annuloplasty is the standard treatment of ischemic mitral regurgitation (MR), however, it has been associated with some drawbacks. It abolishes normal annular dynamics and freezes the posterior leaflet. In the present study, we evaluated Paneth suture annuloplasty in chronic ischemic MR and both early and mid-term outcomes of the technique on a selected *** The study period was from June 2010 to June 2012. We operated on 21 patients who had the diagnosis of coronary artery disease andMR of grade 3 or 4. The patients had both a coronary artery bypass operation and the mitral semicircular reduction annuloplasty described by Paneth-Burr. The data on the patients were retrospectively collected. Patients were contacted by outpatient clinic controls for mid-term results. Results The male/female ratio was 10/11. The mean age of the patients was 71.0 ±6.4 years. Preoperative and postoperative left ventricular ejection fraction was statistically similar (P = 0.973). Early postoperative MR grade (mean, 0.57 ±0.51) was statistically lower than the preoperative MR grades (mean, 3.38 ±0.50) (P leeding. Two patients had prolonged hospitalization, one for sternal infection and the other for severe chronic obstructive pulmonary disease. No hospital or late postoperative deaths occurred. The mean late postoperative MR grade was 0.66 ±0.97 degrees. One patient had progression of MR in the later follow-up, which was treated by mitral valve replacement. Conclusion Semicircular reduction annuloplasty is an effective, inexpensive and easy surgical annuloplasty technique with lowmortality and morbidity in severe symptomatic ischemic MR.

关键词： Mitral valve Myocardial ischemia Surgery

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金属矿田地质勘探类型及其评价方案

地学前缘 2015年第4期22卷 13-21页

作者：吕古贤中国地质科学院地质力学研究所北京100081 长安大学地球科学与资源学院陕西西安710064 中国地质大学(北京)地球科学与资源学院北京100083

地质勘探类型是科学地质调查和有效矿产资源评价的基础和前提。矿田是包含几个矿床的成矿空间,单个矿床的勘探类型不一定适用于矿田的地质勘探。文中遵循"成矿作用、地质工作程度和资源经济条件"的思路,探讨矿田勘探类型和分类问题。以... 详细信息

地质勘探类型是科学地质调查和有效矿产资源评价的基础和前提。矿田是包含几个矿床的成矿空间,单个矿床的勘探类型不一定适用于矿田的地质勘探。文中遵循"成矿作用、地质工作程度和资源经济条件"的思路,探讨矿田勘探类型和分类问题。以地质勘查工作程度(地质调查或勘探报告所遵循的工作精度,即成果图件的比例尺为指标)和资源技术经济条件(各级资源储量的比例,并结合矿山生产规模为指标)为指标,作者建立"地质勘查程度资源经济条件"评价系统。经该系统的综合评价,研究预查矿田(Ⅲ)、普查矿田(Ⅱ)和详查矿田(Ⅰ)的基本地质勘探类型。矿田地质勘探类型的确定,为推动整装勘查区的找矿突破、制定勘查规划和勘探工作的投入提供了可参考的方法和思路。文中选择6个典型矿田,详细展示矿田勘探类型的评价过程和方法。

关键词：矿田勘探类型地质勘查程度资源经济条件评价指标 “地质勘查程度-资源经济条件”评价系统