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    题名 作者 年代 出处 被引量
1西天山“亚洲金腰带”及其动力背景和成矿控制与找矿显示文摘天山西段,从乌兹别克斯坦向东,经吉尔吉斯斯坦到中国新疆西部,在中天山及南北缘巨型和世界级金矿集中产出,构成世人瞩目的巨型金成矿带,即'亚洲金腰带'。为什么能在这个东西延伸近2 500km的带状区域形成'亚洲金腰带'?成矿具有怎样的动力背景?受何要素控制又是怎样发生发展?'亚洲金腰带'内巨型和世界级金矿床主要产在乌兹别克斯坦和吉尔吉斯斯坦,能否在新疆西天山实现金矿找矿重大突破?都是颇受关注的重大地质找矿问题。论文在较多学习前人成果并结合作者研究结果基础上,综述了'亚洲金腰带'动力背景和地质环境、金矿床基本特征,分析了成矿系统类型和关键控制,对接了新疆西天山与乌兹别克斯坦-吉尔吉斯斯坦的构造成矿带。研究认为Terskey洋和Turkestan-南天山洋的发生、发展和消亡是'亚洲金腰带'基本地球动力学背景;'亚洲金腰带'中巨型和世界级金矿分属造山型和斑岩型两个主要成矿系统,'古老地壳+构造变形+岩浆热液'是造山型金成矿关键控制和勘查准则,而成熟岛弧环境、深源岩浆浅成侵入、叠加复合长期成矿是斑岩型金成矿关键控制;中天山是'亚洲金腰带'的核心,自西而东从乌兹别克斯坦经吉尔吉斯斯坦到我国新疆西天山具有可对接和贯通性,'亚洲金腰带'向东延伸确切进入我国新疆西天山;新疆西天山那拉提山—额尔宾山一带的中天山及南北缘造山型金成矿要素齐全且配置好,有望实现金矿找矿重大突破。薛春纪 赵晓波 莫宣学 董连慧 顾雪祥 Bakhtiar Nurtaev Nikolay Pak 张招崇 王新利 俎波 张国震 冯博 刘家瑛 2014地学前缘2014,21,5:81
2西天山巨型金铜铅锌成矿带构造成矿演化和找矿方向显示文摘西天山产有Muruntau、Kumtor、Kalmakyr等巨型金矿床和Kalmakyr、Dal′neye等世界级铜矿床以及Tekeli等超大型铅锌矿床,构成世人瞩目的巨型金铜铅锌成矿带。新疆西天山金、铜、铅锌矿找矿面临重大突破,不断认识乌兹别克斯坦—吉尔吉斯斯坦—哈萨克斯坦东南部—中国新疆西部整个西天山的构造成矿过程,明确新疆西天山金、铜、铅锌矿重大找矿突破方向,预测大型矿集区十分必要。本文通过境内外野外地质矿产广泛调研和对相关文献综合研究,认为西天山造山带形成演化经历前寒武纪古陆边缘裂陷盆地、古生代洋-陆俯冲增生、晚古生代陆-陆碰撞造山、中—新生代坳陷盆地四个主要地质过程,造就出四类重要成矿系统和类型:1元古宙边缘裂陷盆地铅锌成矿系统SEDEX型;2古生代俯冲岛弧金铜铅锌成矿系统斑岩-矽卡岩-浅成低温热液型;3晚古生代碰撞造山金铅锌成矿系统造山型-MVT;4中—新生代坳陷盆地铅锌铜成矿系统砂岩型。综合对比西天山境内外成矿系统地质发育特点,预测新疆西天山那拉提-额尔宾中天山隆起带是造山型金矿找矿重大突破区,吐拉苏盆地和巴音布鲁克中天山以及那拉提山北坡有望实现斑岩型金铜找矿突破,伊犁地块南缘元古宇SEDEX型铅锌找矿值得关注,山间/山前盆地无疑是砂岩型铅锌铜找矿优先选择。薛春纪 赵晓波 莫宣学 陈毓川 董连慧 顾雪祥 张招崇 Bakhtiar NURTAEV Nikolay PAK 李志丹 王新利 张国震 亚夏尔亚力坤 冯博 俎波 刘家瑛 2014地质学报2014,88,12:71
3西天山金铜多金属重要成矿类型、成矿环境及找矿潜力显示文摘西天山跨乌兹别克斯坦、塔吉克斯坦、吉尔吉斯斯坦、哈萨克斯坦南部和中国新疆西天山,东西绵延2500 km,是'亚洲金腰带'核心地带,金铜铅锌矿产优势明显,中国新疆西天山金铜铅锌重大找矿发现令人期待。通过广泛深入的文献调研和较全面的地质矿产调查,论文针对重要成矿类型、成矿环境和找矿潜力的研究表明,西天山金铜铅锌成矿重要类型是造山型金矿、斑岩型金铜矿、SEDEX型和砂岩型铅锌矿等。造山型金矿形成于古生代俯冲增生和碰撞造山两类地质环境,斑岩型金铜矿形成于古生代不同时期的成熟岛弧环境,SEDEX型铅锌矿在新元古代陆缘盆地富集,砂岩型铅锌矿形成于中—新生代山前盆地。西天山金铜铅锌成矿类型和环境优越,找矿潜力巨大,新疆西天山有望实现金铜铅锌找矿持续重大突破。本文为西天山区域成矿研究和金铜铅锌找矿勘查提供了新的参考和引导。薛春纪 赵晓波 张国震 莫宣学 顾雪祥 董连慧 赵树铭 米登江 Bakhtiar Nurtaev Nikolay Pak 李志丹 王新利 俎波 亚夏尔亚力坤 冯博 2015中国地质2015,42,3:39
4西天山造山带构造单元划分及古生代洋陆转换过程显示文摘西天山造山带位于哈萨克斯坦—准噶尔板块与卡拉库姆—塔里木板块的结合部,是由一系列前寒武纪微陆块、古生代洋壳残片及陆缘弧相互拼贴而成的多聚合带、多成矿带,其独特的造山-成矿过程受到了国内外的广泛关注。本文通过构造单元划分与编图,建立了古生代西天山造山带的构造格架,认为古生代西天山造山带的构造演化依次经历了:罗迪尼亚大陆裂解与北天山早古生代多岛洋盆形成阶段(Z-O_2),北天山早古生代多岛洋盆闭合与南天山洋盆开始形成阶段(O_3-S),南、北天山洋晚古生代洋盆形成与发展阶段(D-C_1),南、北天山晚古生代洋盆全面闭合与天山碰撞造山带形成阶段(C1-C_2)和碰撞后板内演化阶段(C_2-P)。王宗秀 李春麟 Pak Nikolai Ivleva Elena 余心起 周高 肖伟峰 韩淑琴 Halilov Zailabidin Takenov Nurgazy 鄢犀利 2017中国地质2017,44,4:20
5Total hip arthroplasty for surgical management of advanced tuberculous hip arthritis:Case report显示文摘Tuberculosis(TB) arthritis of the hip is a debilitating disease that often results in severe cartilage destruction and degeneration of the hip. In advanced cases,arthrodesis of the hip confers benefits to the young,high-demand and active patient. However, many of these patients go on to develop degenerative arthritis of the spine, ipsilateral knee and contralateral hip,necessitating the need for a conversion to total hip arthroplasty. Conversion of a previously fused hip to atotal hip arthroplasty presents as a surgical challenge due to altered anatomy, muscle atrophy, previous surgery and implants, neighbouring joint arthritis and limb length discrepancy. We report a case of advanced TB arthritis of the hip joint in a middle-aged Singaporean Chinese gentleman with a significant past medical history of miliary tuberculosis and previous hip arthrodesis. Considerations in pre-operative planning, surgical approaches and potential pitfalls are discussed and the operative technique utilized and post-operative rehabilitative regime of this patient is described. This case highlights the necessity of pre-operative planning and the operative technique used in the conversion of a previous hip arthrodesis to a total hip arthroplasty in a case of TB hip arthritis.Shi Ming Tan Pak Lin Chin 2015World Journal of Orthopedics2015,6,2:10
6Generation of hircine-induced pluripotent stem cells by somatic cell reprogramming显示文摘Jiangtao Ren Yongjun Pak Lixiazi He Lei Qian Yijun Gu Hui Li Lingjun Rao Jing Liao Chun Cui Xun Xu Jinqiu Zhou Hakchol Ri Lei Xiao 2011Cell Research2011,21,5:10
7Testicular sperm extraction and intracytoplasmic sperm injection in non obstructive azoospermia显示文摘Objective To report the experience in sperm extraction from testicular biopsies (TESE) performed from March 1996 to July 1998 in men with non obstructive azoospermia (NOA) Methods Comparisons of age, volume of both testes, serum FSH and testosterone in men, and histology of testicular samples in the first cycles between cycles with spermatozoa found and those without spermatozoa found were performed Comparisons of fertilization, cleavage and pregnancy rates between cycles with spermatozoa injected and those with spermatids injected were performed Results Spermatozoa were found in only 12 out of 26 first TESE cycles (46 2%) and other cycles had spermatids (round cells) only Age of men, history of mumps orchitis/oligozoospermia, volume of both testes and serum FSH/testosterone levels in men were not significantly different between cycles with and without spermatozoa The fertilization rate was significantly higher in cycles with spermatozoa injected than those with round cell injections (63 3% vs 23 2%, P <0 0001, Chi squared test) The pregnancy rate was 14 3% per cycle when spermatozoa were injected Conclusions TESE followed by Intracytoplasmic sperm injection (ICSI) is an effective treatment in patients with NOA Less than half of the patients undergoing TESE had spermatozoa recovered Age of men, volume of both testes and serum FSH/ testosterone levels in men were not useful in predicting successful recovery Compared to using ejaculated and epididymal spermatozoa, fertilization and pregnancy rates were achieved when testicular spermatozoa were used forNg Hung Yu Ernest, Lau Yee Lan, Yeung Shu Biu, So Wai Ki, Tam Po Chor and Ho Pak Chung 2000Chinese Medical Journal2000,,3:7
8Investigation of rock salt layer creep and its effects on casing collapse显示文摘Casing collapse is one of the costly incidents in the oil industry. In the oil fields of southwest Iran, most casing collapses have occurred in Gachsaran formation, and the halite rock salt layer in this formation may be the main cause for these incidents because of its peculiar creep behavior. In this research, triaxial creep experiments have been conducted on Gachsaran salt samples under various temperatures and differential stresses. The main purpose was to determine the creep characteristics of Gachsaran rock salt,and to examine the role of creep in several casing collapses that occurred in this formation. Results indicated that the halite rock salt of Gachsaran formation basically obeys the power law;however, its creep parameters are quite different from other halite rocks elsewhere. The time-dependent creep of Gachsaran rock salt exhibits strong sensitivity to temperature change;however, its sensitivity to variation of differential stress is rather low. The numerical simulation of the rock salt creep in a real oil well demonstrated the importance of creep and reservoir conditions on the safety factor of the tubing related to casing collapse.S.Reza Taheri Ali Pak Saeed Shad Behzad Mehrgini Meisam Razifar 2020International Journal of Mining Science and Technology2020,30,3:6
9Effects of land use change and water reuse options on urban water cycle显示文摘The aim of this article was to study the effects of land use change and water reuse options on an urban water cycle.A water cycle analysis was performed on the Goonja drainage basin,located in metropolitan Seoul,using the Aquacycle model.The chronological effects of urbanization were first assessed for the land uses of the Goonja drainage basin from 1975 to 2005,where the ratio of impervious areas ranged from 43% to 84%.Progressive urbanization was identified as leading to a decrease in evapotranspiration (29%),an increase in surface runoff (41%) and a decrease in groundwater recharge (74%),indicating a serious distortion of the water cycle.From a subsequent analysis of the water reuse options,such as rainwater use and wastewater reuse,it is concluded that wastewater reuse seemed to have an advantage over rainwater use for providing a consistent water supply throughout the year for a country like Korea,where the rainy season is concentrated during the summer monsoon.Jiho Lee Gijung Pak Chulsang Yoo Sangdan Kim Jaeyoung Yoon 2010Journal of Environmental Sciences2010,22,6:6
10PLINK: A Tool Set for Whole-Genome Association and Population-Based Linkage Analyses显示文摘Shaun Purcell Benjamin Neale Kathe Todd-Brown Lori Thomas Manuel A.R. Ferreira David Bender Julian Maller Pamela Sklar Paul I.W. de Bakker Mark J. Daly Pak C. Sham 2007The American Journal of Human Genetics2007,,3:5
11玉米秸秆生物炭对水中对苯醌的吸附性能研究显示文摘资源环境问题一直受到人们的广泛关注,农业废弃物玉米秸秆可以用来提取油气,副产物生物炭预期能够用于环境治理。在600℃条件下,通过简单的限氧热解法制备得到玉米秸秆生物炭,将其用于吸附去除在高级氧化过程中产生的中间氧化产物——对苯醌,研究了玉米秸秆生物炭的投加量和溶液初始pH值对吸附效果的影响,玉米秸秆生物炭吸附对苯醌的动力学、热力学作用机理,玉米秸秆生物炭的再生利用性能等。研究结果表明:①玉米秸秆生物炭能够高效吸附去除对苯醌,投加量为0.8 g/L时的去除率可达到97.2%。②在较宽的pH值变化范围内(3.0-11.0)均表现出了较高的去除能力,且生物炭和对苯醌之间产生的∏-∏电子供体-受体(∏-∏electron-donor-acceptor interaction)相互作用占主导。③Elovich和准二级动力学模型均能较好地拟合试验动力学数据,表明玉米秸秆生物炭与对苯醌之间可能存在扩散控制的化学吸附过程。④基于Langmuir模型的玉米秸秆生物炭对对苯醌的最大吸附量qmax为94.6 mg/g;与Langmuir模型相比,Freundlich模型能够更好地拟合试验热力学数据,且玉米秸秆生物炭对对苯醌的吸附在很大程度上是多分子层吸附过程。⑤多次循环再生后的玉米秸秆生物炭仍具有较好的吸附去除率。李国亭 康恒嘉 赵宝龙 张帅阳 李康丽 PAK Tannaz 2020华北水利水电大学学报(自然科学版)2020,41,4:5
12Rational use of mesenchymal stem cells in the treatment of autism spectrum disorders显示文摘Autism and autism spectrum disorders(ASD) refer to a range of conditions characterized by impaired social and communication skills and repetitive behaviors caused by different combinations of genetic and environmental influences. Although the pathophysiology underlying ASD is still unclear, recent evidence suggests that immune dysregulation and neuroinflammation play a role in the etiology of ASD. In particular, there is direct evidence supporting a role for maternal immune activation during prenatal life in neurodevelopmental conditions. Currently, the available options of behavioral therapies and pharmacological and supportive nutritional treatments in ASD are only symptomatic. Given the disturbing rise in the incidence of ASD, and the fact that there is no effective pharmacological therapy for ASD, there is an urgent need for new therapeutic options. Mesenchymal stem cells(MSCs) possess immunomodulatory properties that make them relevant to several diseases associated with inflammation and tissue damage. The paracrine regenerative mechanisms of MSCs are also suggested to be therapeutically beneficial for ASD.Thus the underlying pathology in ASD, including immune system dysregulation and inflammation, represent potential targets for MSC therapy. This review willfocus on immune dysfunction in the pathogenesis of ASD and will further discuss the therapeutic potential for MSCs in mediating ASD-related immunological disorders.Qiang Liu Mo-Xian Chen Lin Sun Chloe U Wallis Jian-Song Zhou Li-Juan Ao Qi Li Pak C Sham 2019World Journal of Stem Cells2019,11,2:5
13A cross-sectional study on compliance with topical glaucoma medication and its associated socioeconomic burden for a Chinese population显示文摘AIM: To estimate the overall drug compliance for local Chinese glaucoma patients on long-term topical treatment.METHODS: This was a retrospective cross-sectional study.Fifty-seven primary glaucoma patients from the subspecialty clinic of a publicly-funded tertiary care hospital in Hong Kong completed a questionnaire on compliance with topical glaucoma medication,attitude towards glaucoma and therapy and vision related quality of life.Noncompliance was defined as reporting missing more than or equal to 10% of the prescribed topical glaucoma medication during the 2wk immediately prior to the consultation.Relationships between noncompliance and demographics,attitude,disease and treatment status was studied.Cost was estimated with quality of life and direct medical cost involved with noncompliance.Multivariable logistic regression on noncompliance was performed on selected factors.RESULTS: Compliance was calculated as 75%(95% CI: 64%-87%) among 57 subjects(mean age 69 y,female 51%).No statistical significant relationship was established between noncompliance and any single factors or outcomes.Age(P=0.048) and forgetfulness(P=0.064) were found to be marginally significant predictive factors on noncompliance in multivariable logistic regression.Noncompliance might be related(P=0.130) to poorer self-rated vision-associated quality of life.The societal cost of noncompliance was estimated to be over 2510 life-years and US$ 3.7 million territory-wide.CONCLUSION: The compliance of Chinese glaucoma patients in Hong Kong is comparable to other parts in the world,and carries detrimental impacts on individual and societal levels.Age and forgetfulness are two possible independent predictors for noncompliance.Man-Hin Lui Jason Chun Ho Lam Yi Lee Kwong Tak Siu Wong Pak Long Cheung Sherri Shun Yan Lai Pak Lun Yuen Wai Yiu Lam Ho Yan Chan Yiu Fai Wong Jimmy Shiu Ming Lai Kendrick Co Shih 2017International Journal of Ophthalmology(English edition)2017,10,2:5
14中国及境外天山铅锌成矿作用与找矿方向显示文摘中国及境外天山铅锌矿床多有发现,如哈萨克斯坦Tekeli、Shalkiya和Achisai,乌兹别克斯坦Kurgashinkan和Uchkulach,塔吉克斯坦Altyntopkan,中国新疆乌拉根、彩霞山、阿齐山、阿尔恰勒等大型—超大型铅锌矿床,构成了天山巨型铅锌成矿带。这些铅锌矿床形成于怎样的地球动力学背景?铅锌成矿的基本地质特征是什么?有哪些重要成矿类型?受何要素控制?未来找矿突破方向在哪里?这些都是颇受关注的地质找矿问题。在广泛矿产地质调查和综合分析前人研究成果的基础上,将中国及境外天山作为整体,综述了天山造山带构造演化和重要铅锌成矿环境、典型矿床特征与成矿系统/成矿类型,总结了天山地区铅锌成矿演化过程,并分析了区域铅锌成矿特点与找矿突破方向。结果表明:天山造山带经历了前寒武纪古陆形成、洋-陆俯冲增生、陆-陆碰撞造山和陆内成盆4个地球动力学过程,先后出现了元古宙古陆边缘裂陷盆地、古生代洋-陆俯冲增生岛弧、晚古生代陆-陆碰撞造山与中—新生代山前/山间盆地4类重要铅锌成矿环境。在元古宙古陆边缘裂陷盆地环境,主要受同生断层、还原性细碎屑岩-碳酸盐岩建造等控制,形成了古陆边缘裂陷盆地铅锌成矿系统与SEDEX型铅锌矿床;在古生代洋-陆俯冲增生岛弧环境,主要受弧岩浆活动、断裂构造、地层等控制,形成了增生岛弧铅锌成矿系统与矽卡岩型、斑岩型、岩浆热液脉型、VMS型铅锌矿床;在晚古生代陆-陆碰撞造山环境,主要受被动陆缘海相碳酸盐岩、张性开放空间、逆冲推覆构造等控制,形成了碰撞造山铅锌成矿系统与MVT型铅锌矿床;在中—新生代山前/山间盆地环境,主要受盆地三元结构、油气运移与红层“漂白”、硫酸盐岩等控制,形成了山前/山间盆地铅锌成矿系统与砂岩型铅锌矿床。由此可见,天山地区存在多种铅锌成矿环境和不同铅锌成矿系统与成矿类型,其铅锌成矿表现出长时间、多期次、多类型叠合成矿和一定继承性的演化特点。尽管沉积岩容矿铅锌矿床(包括SEDEX型、MVT型和砂岩型)在全球铅锌矿产资源中占据主导地位,而在天山地区增生岛弧铅锌成矿系统则占有更为重要的地位,特别是北天山岛弧带,哈萨克斯坦—伊犁板块南、北缘和中天山地块应该给予高度重视。与此同时,哈萨克斯坦—伊犁板块北缘与东天山中天山地块元古界SEDEX型铅锌找矿、境外中天山地块北缘与南天山造山带古生代被动陆缘碳酸盐岩地层MVT型铅锌找矿、新疆西南天山山前/山间盆地砂岩型铅锌找矿前景良好,也仍值得持续关注。高荣臻 薛春纪 满荣浩 代俊峰 赵晓波 赵云 亚夏尔·亚力坤 Bakhtiar NURTAEV Nikolay PAK 莫宣学 2021地球科学与环境学报2021,43,1:4
15An Adaptive Nonsingular Fast Terminal Sliding Mode Control for Yaw Stability Control of Bus Based on STI Tire Model显示文摘Due to the bus characteristics of large quality,high center of gravity and narrow wheelbase,the research of its yaw stability control(YSC)system has become the focus in the field of vehicle system dynamics.However,the tire nonlinear mechanical properties and the effectiveness of the YSC control system are not considered carefully in the current research.In this paper,a novel adaptive nonsingular fast terminal sliding mode(ANFTSM)control scheme for YSC is proposed to improve the bus curve driving stability and safety on slippery roads.Firstly,the STI(Systems Technologies Inc.)tire model,which can effectively reflect the nonlinear coupling relationship between the tire longitudinal force and lateral force,is established based on experimental data and firstly adopted in the bus YSC system design.On this basis,a more accurate bus lateral dynamics model is built and a novel YSC strategy based on ANFTSM,which has the merits of fast transient response,finite time convergence and high robustness against uncertainties and external disturbances,is designed.Thirdly,to solve the optimal allocation problem of the tire forces,whose objective is to achieve the desired direct yaw moment through the effective distribution of the brake force of each tire,the robust least-squares allocation method is adopted.To verify the feasibility,effectiveness and practicality of the proposed bus YSC approach,the TruckSim-Simulink co-simulation results are finally provided.The co-simulation results show that the lateral stability of bus under special driving conditions has been significantly improved.This research proposes a more effective design method for bus YSC system based on a more accurate tire model.Xiaoqiang Sun Yujun Wang Yingfeng Cai Pak Kin Wong Long Chen 2021Chinese Journal of Mechanical Engineering2021,34,4:4
16一般人群中腹型肥胖和新发心房颤动的关系显示文摘已知身高越高,体质量越大,心房颤动发生风险越高。然而,心房颤动的风险是否与腹型肥胖有关尚不清楚。Baek等纳入韩国国民健康保险计划全国样本队列中基线无心房颤动的成人501 690人,年龄(47.6±14.3)岁,女性250 664人,占50%。测定其体质量指数(body mass index,BMI)和腰围,将BMI〈18.5kg/m2定义为低体质量,18.5~〈25.0kg/m2定义为正常体质量;25.0~〈30.0kg/m2定义为超重;≥30.0kg/m2定义为肥胖;将腰围≥90(男性)和≥80cm(女性)定义为腹型肥胖。刘莉 叶鹏 Baek YS Yang PS Kim TH Uhm JS Park J Pak HN Lee MH Joung B 2017中华高血压杂志2017,25,9:4
17南阿尔金尤努斯萨依高压花岗质片麻岩原岩的形成时代与地球化学特征:对南阿尔金陆壳深俯冲板片属性的进一步限定显示文摘南阿尔金尤努斯萨依地区出露的高压花岗质片麻岩的SiO2=71.01%~75.07%,Al2O3=12.31%~14.21%,全碱Na2O+K2O=7.44%~8.37%,MgO=0.26%~0.60%,TFeO=1.75%~2.62%,CaO=0.95%~1.70%,具有高硅、高铝、高碱性的特征,属于钙碱性过铝质花岗质岩石。其稀土总量为131.15×10^-6~234.34×10^-6,相对富集Rb、Th、La等大离子亲石元素而亏损Ba、Ta、Nb、Sr、Ti,∑LREE/∑HREE=5.07~7.67,(La/Yb)N=4.82~9.58,具有强烈的Eu亏损(δEu=0.42~0.63),显示出S型花岗岩的特征。岩石Sr/Ba值(0.11~0.15)较低,CaO/Na2O=0.44~0.75>0.3,显示原岩可能为陆壳沉积的杂砂质岩石。LA-ICP-MS锆石U-Pb定年表明该花岗质高压岩石原岩的形成时代约为900 Ma,指示其所代表的构造岩浆事件可能与阿尔金及其周缘广泛报道的新元古代Rodinia超大陆汇聚的地质事件相关,并进一步限定其侵入的阿尔金杂岩的形成时代主体应为早新元古代。该高压花岗质片麻岩原岩的形成时代(~900 Ma)远大于其发生高压变质的时代(~500 Ma),表明其原岩就位于地壳约400 Ma之后才发生俯冲遭受高压变质作用。显然,该高压岩石的形成是陆壳俯冲作用的产物,为进一步限定南阿尔金早古生代陆壳俯冲-深俯冲作用提供了新的依据。PAK Sang Wan 马拓 盖永升 康磊 王超 廖小莹 刘良 2019西北地质2019,52,4:4
18中阿尔金南缘志留纪高压泥质片麻岩的发现及其构造地质意义显示文摘在中阿尔金南缘西段尤努斯萨依北部原划长城系巴什库尔干岩群中首次发现一套高压泥质片麻岩。根据岩相学观察和矿物化学成分可识别出其四期矿物共生组合:早期为石榴子石+多硅白云母+单斜辉石(?)+斜长石+黑云母+石英+金红石+钛铁矿;第二期为石榴子石+蓝晶石+钾长石+斜长石+黑云母+石英+金红石+钛铁矿;第三期为石榴子石+夕线石+钾长石+斜长石+黑云母+石英+金红石+钛铁矿;晚期为石榴子石+夕线石+斜长石+黑云母+石英+钛铁矿。依据矿物内部一致性热力学数据,基于THERMOCALC 3. 40程序平台,计算出P-T视剖面图,并结合矿物等值线、矿物对温压计等计算,依次确定四期变质温压条件为15. 8~18. 3kbar/646~729℃、10. 30~12. 30kbar/781~821℃、8. 50~9. 60kbar/812~838℃和4. 65~5. 70kbar/698~725℃。上述四期变质阶段共同构成一个早期降压升温后降压降温的顺时针型演化的P-T轨迹,指示出与陆壳俯冲-折返相关的变质地质事件。利用LA-ICP-MS进行的锆石原位微区U-Pb定年和微量元素分析结果表明,该岩石记录了432. 0±2. 7Ma、401. 4±2. 5Ma和381. 1±2. 4Ma三期变质年龄,可能分别代表了该岩石早期高压、中期高压麻粒岩相-麻粒岩相和后期角闪岩相变质阶段的时代。该高压岩石出露于中阿尔金地块西段南缘长城系巴什库尔干岩群之中,与南侧以断裂带分隔的赋存于阿尔金岩群之中的南阿尔金高压-超高压岩石出露的构造位置明显不同,其峰期变质时代(~432Ma)亦明显不同于南阿尔金高压-超高压岩石的峰期变质时代(~500Ma)。因此,该高压岩石与南阿尔金高压-超高压岩石显然不能构成同一条变质岩带。结合区域地质背景和前人关于柴北缘陆壳属性高压-超高压岩石峰期变质时代(~430Ma)的研究成果综合分析,本文初步认为该高压岩石可能是柴北缘高压-超高压变质岩带的西延或是被中新生代以来阿尔金复杂多期次走滑断裂系迁移而就位于中阿尔金南缘的部分柴北缘高压-超高压变质岩片/岩块。马拓 刘良 盖永升 杨文强 王超 康磊 廖小莹 PAK SangWan 2019岩石学报2019,35,6:4
19A modeling method for vibration analysis of cracked beam with arbitrary boundary condition显示文摘This paper establishes a cracked Timoshenko beams model to investigate the vibration behavior based on the ultraspherical polynomials.Timoshenko beam theory is applied to model the free vibration analysis of the cracked beam and the numerical results are obtained by using ultraspherical orthogonal polynomials.The boundary conditions of both ends of the cracked beam are modeled as the elastic spring and the beam is divided into two parts by the crack section,and continuous conditions at the connecting face are modeled by the inverse of the flexibility coefficients of fracture mechanics theory.Ignoring the influence of boundary conditions,displacements admissible functions of cracked Timoshenko beam can be set up as ultraspherical orthogonal polynomials.The accuracy and robustness of the present method are evidenced through comparison with previous literature and the results achieved by the finite element method(FEM).In addition,the effects of flexibility coefficient on the natural frequencies are also investigated by using the proposed method.Numerical examples are given for free vibration analysis of cracked beams with various boundary conditions,which may be provided as reference data for future study.Kwanghun Kim Sok Kim Kyongjin Sok Chanil Pak Kwangbok Han 2018Journal of Ocean Engineering and Science2018,3,4:4
20论香港国际机场起飞着陆滑行区域气象回避路线的识别(英文)显示文摘空中交通的安全和效率明显受恶劣天气的影响,在机场起飞着陆滑行区域(TMA)尤其如此。在此区域,除了受天气影响之外,潜在的气象回避路线还受到空中交通管制的严格限制。因此气象回避模型DIVMET被开发出来。该模型给出一条建议路线,可以通过正在形成雷暴但尚未在里面实施任何空中交通管制的场地。DIVMET被应用到香港国际机场的TMA区域,因为此处的空中交通管制(ATC)单位有兴趣通过模拟回避路线来提高管制员的工作量,尤其是用于管理进场飞机交通。ATC单位对模拟的回避路线进行目视检查,其结果令人满意,但是商定了用实际观察到的路线对模拟情况进行定量验证。本文选择了香港TMA区域内有雷暴且交通严重扭曲时的两种真实恶劣天气情况。但是,进行任何验证之前的主要目标是识别仅仅受到天气影响但并未显示任何管制标志的路线。在飞行位置数据的基础上完成路线选择,选择若干着陆航班,并分析与标准进场路线的偏差。结果显示,272架航班中大多数同时受到天气和管制的影响(60%),这突出表明空中交通管制员在恶劣天气下要安全有效地管理着陆交通是存在挑战的。只有少数受天气影响的航班(7%)未受到管制,可以用于验证。DIVMET模拟路线被传给当地空中交通管制员,证明了这些路线是潜在切实的回避路线。在TMA区域内的DIVMET气象回避路线模拟有一定参考价值,但是进一步的模型开发必须将管制纳入考虑,至少要考虑停候、近道和减速。Manuela SAUER Thomas HAUF Ludmila SAKIEW Pak Wai CHAN Shuk-Mei TSE Patrick HUPE 2016Journal of Zhejiang University-Science A(Applied Physics & Engineering)2016,17,3:3
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