The Tiegelongnan Cu(Au,Ag)deposit in central Tibet contains more than 10 Mt of copper ranking 29 th in the world.It is characterized by typical porphyry-epithermal alteration and mineralization.In order to improve the...The Tiegelongnan Cu(Au,Ag)deposit in central Tibet contains more than 10 Mt of copper ranking 29 th in the world.It is characterized by typical porphyry-epithermal alteration and mineralization.In order to improve the understanding of porphyry-epithermal copper deposit in Tibet,new zircon U-Pb age and sulfur isotope data along with published data in the Tiegelongnan are presented to investigate the formation and preservation mechanism.Ore-related intrusive rocks in the Tiegelongnan including Early Cretaceous(about 120 Ma)granodiorite porphyry and diorite porphyry are closely related to the northward subduction of Bangongco-Nujiang ocean.Sulfur mainly comes from deep magma,and ore-forming fluid is affected by both magmatic and meteoric water.The metallogenic setting of Tiegelongnan is consistent with those of Andean porphyry copper deposits in South America.The cover of the Meiriqiecuo Formation volcanic rocks,Lhasa-Qiangtang collision and India-Eurasian collision have significance in the preservation and uplift of the deposit.The formation,preservation and discovery of Tiegelongnan play an important role in exploration of ancient porphyry-epithermal deposits in Tibet.展开更多
设计了一种基于四阶脉冲幅度调制(PAM4)技术的50 Gbit/s 40 km QSFP28封装的长距离光传输模块,以应对现代社会对通信传输的带宽、速率和容量等要求的不断增长。使用了PAM4技术以提高单波长的数据传输容量,使得单波传输速率达到50 Gbit/s...设计了一种基于四阶脉冲幅度调制(PAM4)技术的50 Gbit/s 40 km QSFP28封装的长距离光传输模块,以应对现代社会对通信传输的带宽、速率和容量等要求的不断增长。使用了PAM4技术以提高单波长的数据传输容量,使得单波传输速率达到50 Gbit/s;在模块的接收单元使用雪崩光电二极管(APD)作为光探测器,使得模块对小光信号的接收能力得到提高;测试结果表明,模块的性能较为稳定,优化了APD部分电路设计,以获得更佳的传输效果,能够满足50 GE 40 km传输。展开更多
The low accuracy using unstructured meshes to solve complicated geometry problems is a significant challenge in practical engineering.It is the key to solve this issue through enhancing the accuracy of tetrahedral ele...The low accuracy using unstructured meshes to solve complicated geometry problems is a significant challenge in practical engineering.It is the key to solve this issue through enhancing the accuracy of tetrahedral element.This work develops a simple strategy to enhance the accuracy of tetrahedral element with the Shepard interpolation function.In which the strain field is reconstructed by introducing the weighted strains of adjacent tetrahedral elements to central tetrahedral element.The stiffness of the discrete system is significantly softened with this simple operation,which leads to a great accuracy improvement.Furthermore,this simple modification makes linear tetrahedral element owns higher accuracy even compared with hexahedral element.The high precision tetrahedral element makes finite element analysis more acceptable for engineers.It provides a novel solution to finite element analysis using unstructured meshes for practical engineering problems with complicated geometry.In order to validate the accuracy and feasibility of present modified tetrahedral element(M-T4)in complicated geometry problems,several engineering examples are performed,including linear static analysis,modal analysis,frequency response analysis,transient response analysis,and response spectrum analysis.The remarkable performance of the M-T4 suggests its wide applicability to practical engineering problems.展开更多
基金funded by the National Natural Science Foundation of China(42002103)the Technical Service for Quality Monitoring of Mineral Exploration in Tiegelongnan Mining Area,Duolong Ore district,Gaize County,Tibet(XZJL-JS-2021-004)+1 种基金the Chinese Geological Survey(DD20190167)the Basal Research Fund of Chinese Academy of Geological Sciences(KK2017)。
文摘The Tiegelongnan Cu(Au,Ag)deposit in central Tibet contains more than 10 Mt of copper ranking 29 th in the world.It is characterized by typical porphyry-epithermal alteration and mineralization.In order to improve the understanding of porphyry-epithermal copper deposit in Tibet,new zircon U-Pb age and sulfur isotope data along with published data in the Tiegelongnan are presented to investigate the formation and preservation mechanism.Ore-related intrusive rocks in the Tiegelongnan including Early Cretaceous(about 120 Ma)granodiorite porphyry and diorite porphyry are closely related to the northward subduction of Bangongco-Nujiang ocean.Sulfur mainly comes from deep magma,and ore-forming fluid is affected by both magmatic and meteoric water.The metallogenic setting of Tiegelongnan is consistent with those of Andean porphyry copper deposits in South America.The cover of the Meiriqiecuo Formation volcanic rocks,Lhasa-Qiangtang collision and India-Eurasian collision have significance in the preservation and uplift of the deposit.The formation,preservation and discovery of Tiegelongnan play an important role in exploration of ancient porphyry-epithermal deposits in Tibet.
文摘设计了一种基于四阶脉冲幅度调制(PAM4)技术的50 Gbit/s 40 km QSFP28封装的长距离光传输模块,以应对现代社会对通信传输的带宽、速率和容量等要求的不断增长。使用了PAM4技术以提高单波长的数据传输容量,使得单波传输速率达到50 Gbit/s;在模块的接收单元使用雪崩光电二极管(APD)作为光探测器,使得模块对小光信号的接收能力得到提高;测试结果表明,模块的性能较为稳定,优化了APD部分电路设计,以获得更佳的传输效果,能够满足50 GE 40 km传输。
基金supported by the National Key R&D Program of China(No.2022YFB2503505)National Natural Science Foundation of China(No.12002124)+3 种基金National Natural Science Foundation of China(No.12302259)China Postdoctoral Science Foundation(No.2021M690965)Changsha Municipal Natural Science Foundation(No.kq2014035)Natural Science Foundation of Hunan Province(No.2022JJ40031).
文摘The low accuracy using unstructured meshes to solve complicated geometry problems is a significant challenge in practical engineering.It is the key to solve this issue through enhancing the accuracy of tetrahedral element.This work develops a simple strategy to enhance the accuracy of tetrahedral element with the Shepard interpolation function.In which the strain field is reconstructed by introducing the weighted strains of adjacent tetrahedral elements to central tetrahedral element.The stiffness of the discrete system is significantly softened with this simple operation,which leads to a great accuracy improvement.Furthermore,this simple modification makes linear tetrahedral element owns higher accuracy even compared with hexahedral element.The high precision tetrahedral element makes finite element analysis more acceptable for engineers.It provides a novel solution to finite element analysis using unstructured meshes for practical engineering problems with complicated geometry.In order to validate the accuracy and feasibility of present modified tetrahedral element(M-T4)in complicated geometry problems,several engineering examples are performed,including linear static analysis,modal analysis,frequency response analysis,transient response analysis,and response spectrum analysis.The remarkable performance of the M-T4 suggests its wide applicability to practical engineering problems.
