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陕西小秦岭地区碳酸岩时空分布、地球化学特征及其与铀稀土成矿作用的关系

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地质力学学报 2024年第1期30卷 147-167页

作者：康清清陈正乐潘家永李鹏刘玉龙李雷江宏君高成东华理工大学核资源与环境国家重点实验室江西南昌330013 中陕核工业集团二二四大队有限公司陕西西安710024 中国地质科学院地质力学研究所北京100081 中国科学院广州地球化学研究所广东广州510640 中陕核工业集团二一四大队有限公司陕西西安710100

碳酸岩作为一种岩浆成因的岩石类型,是铀、稀土等矿产的重要含矿母岩。陕西小秦岭地区广泛分布着碳酸岩,呈大脉状、群脉状、网脉状沿断裂构造侵入太古代变质基底、长城系熊耳群火山沉积岩及蓟县系高山河群碎屑岩中。基于野外穿插关系,... 详细信息

碳酸岩作为一种岩浆成因的岩石类型,是铀、稀土等矿产的重要含矿母岩。陕西小秦岭地区广泛分布着碳酸岩,呈大脉状、群脉状、网脉状沿断裂构造侵入太古代变质基底、长城系熊耳群火山沉积岩及蓟县系高山河群碎屑岩中。基于野外穿插关系,结合碳酸岩主要矿物组合特征,将小秦岭碳酸岩划分为5个阶段,由老到新分别为:霓辉石正长岩阶段、霓辉石碳酸岩阶段、钾长石碳酸岩阶段、石英碳酸岩阶段和含沸石碳酸岩阶段,碳酸岩由早期铁碳酸岩向晚期钙碳酸岩演化。在空间上碳酸岩大致以近东西向小河断裂为界,南北部碳酸岩脉的主要类型存在明显的差异;在时间上碳酸岩总体形成于晚三叠世,但不同地段不同类型碳酸岩存在较为明显的时间差异性。碳酸岩地球化学特征显示高硅、富碱、低镁、高钡锶−稀土元素的特征,以及异常高的钾钠比值;CaO含量、TiO_(2)含量、Al_(2)O_(3)含量、铁镁质含量、全碱含量、稀土元素总量及分馏程度均有自早期碳酸岩到晚期碳酸岩逐渐降低的趋势;MnO含量与重稀土元素含量变化相反,且两者呈线性相关特征;与国内其他地区碳酸岩地球化学特征具有明显的差异性。不同类型碳酸岩具有显著的成矿专属性:早期的霓辉石正长岩、霓辉石碳酸岩、钾长石碳酸岩主要富集铀(铌),钾长石碳酸岩还富集钼;晚期的石英碳酸岩主要富集钼、重稀土元素。碳酸岩的侵入致使围岩发生了普遍的霓长岩化作用,由此导致的钾钠元素的迁移可能是碳酸岩成矿专属特征的重要指标和原因。研究结果为小秦岭地区碳酸岩型铀、稀土等多金属矿的区域勘探提供了有价值的信息。

关键词：陕西小秦岭碳酸岩类型划分地球化学成矿指示

Effects of surface topography and specimen thickness on high-speed raindrop impact damage of CFRP laminates

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Chinese Journal of Aeronautics 2023年第6期36卷 186-200页

作者： Naidan HOU Renxi ZHAO Xuan WANg Zhongbin TANg Hao CUI yulong LI School of Aeronautics Northwestern Polytechnical UniversityXi'an 710072China Joint International Research Laboratory of Impact Dynamics and Engineering Application Xi'an 710072China Shaanxi Key Laboratory of Impact Dynamics and Engineering Application Xi'an 710072China School of Civil Aviation Northwestern Polytechnical UniversitySuzhou 215400China NPU Yangzi River Delta Research Institute Suzhou 215400China

Raindrop impact erosion has been observed since early days of aviation,and can be catastrophic for exposed materials during supersonic flight.A single impact waterjet apparatus is established for mimicking drop impacts at the velocities between 350 m/s and 620 m/*** Fiber Reinforced Polymer(CFRP)laminates with three different surface morphologies and specimen thicknesses are tested here.A central region with no visible damage has been noticed,surrounded by a"failure ring"with common damage patterns including resin removal,matrix cracking,fiber breakage and mass fiber *** features are presented in the"failure ring"whose whole scope extends larger along the longitudinal direction than the transverse direction of the top *** mechanism of the resin removal is related to fiber-matrix debonding,and its onset and propagation can be facilitated by initial surface asperities with the shear action of the lateral *** cases of multiple impact,good surface quality can slow down the evolution of resin removal and fiber exposure on the CFRP surface,reducing the erosion speed and delaying the occurrence of structural damages in the subsequent *** wave dominates the occurrence of matrix cracking on the CFRP surface,and subsequently,results in material loss and peeling of the top-layer because of lateral *** the increase of the specimen thickness,both the interlaminar and intralaminar failures decrease as the impact damage mechanism changes from plate bending stress to the reflection of stress waves.

关键词： Carbon fiber reinforced plastics Failure analysis Impact testing Lateral jetting Surface roughness Waterjet

Damage sensitivity of a wing-type leading edge structure impacted by a bird

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Chinese Journal of Aeronautics 2023年第5期36卷 328-343页

作者： Jun LIU Chunyang ZHANg Bopeng JUAN Zhenhua LI Chao ZHANg yulong LI School of Aeronautics Northwestern Polytechnical UniversityXi’an 710072China

On the windward side of an aircraft,the components with higher probability of impact with birds are the wing-type leading edge structures,such as the wing and tail.A study on the damage sensitivity of a wing-type leading edge structure under bird strikes was presented in this ***,a bird strike test was carried out on a *** principles of the bird strike test equipment and method were introduced in detail,including the bird strike test system,bird projectile production process and data acquisition *** dynamic strain measurement results,the high-speed camera videos,and the final deformation and damage morphology observations of the structure were *** on the coupled Smooth Particle Hydrodynamics(SPH)-Finite Element Method(FEM),the commercial software PAM-CRASH was used to simulate the process of a bird strike with the *** good agreement between the finite element simulation results and the experimental results shows that the calculation method and the numerical model presented in this paper were *** this basis,wing-type leading edge structures can be designed by adding triangular *** bird strike resistances of an original structure and improved structure were studied by numerical *** calculated results show that the improved wing-type leading edge structure is less damaged than the original structure under bird *** improved leading edge structure satisfied the anti-bird strike airworthiness requirements,as the thickness of the triangular support was 1.2 mm,and the weight of the structure was reduced by 0.87 kg compared with the original *** indicated that the bird strike resistance of the improved structure is better than that of the original structure,and the improved design of the wing-type leading edge structure presented in this paper is reasonable.

关键词： Bird impact Damage sensitivity FEM SPH Wing-type leading edge

Surface wettability and flow properties of non-metallic pipes in laminar flow

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Chinese Journal of Chemical Engineering 2020年第3期28卷 636-642页

作者： Hongyuan Qi Aiguo Liang Huayi Jiang Jianying Shi Nana Sun yulong Wang College of Petroleum Engineering Xi'an Shiyou UniversityXi'an 710065China Shaanxi Key Laboratory of Advanced Stimulation Technology for Oil&gas Reservoirs Xi'an Shiyou UniversityXi'an 710065China Karamay Hongshan Oilfield Co.Ltd. Karamay 834000China No.1 Production Plant Xinjiang Oilfield Branch CompanyKaramay 834000China

In this paper,three liquids flowing in five pipes with the same inner diameter of 14 mm were studied to determine the relationship between the surface wettability and flow properties in laminar flow(Re b 2000).This was motivated by oilfield observations of increased pressure drops in non-metallic pipes compared to those in metal pipes,which was contrary to expectations.A new expression for the frictional coefficient that considers the Reynolds number and contact angleθin laminar flow for non-metallic pipes was proposed based on the experimental results of single-phase flow using dimension and regression *** solutions of the anomalous phenomenon were proposed from the perspectives of the pipe diameter,contact-angle difference,and the compatibility between flexible composite pipe and JLHW105 oil according to the new *** surprising finding was that the surface wettability could control the frictional resistance by the critical contact angle(39.9°)obtained at the same Reynolds *** 0°bθ≤39.9°,the frictional coefficient increased as the contact angle *** contrast,if 39.9°bθb 180°,the frictional coefficient decreased with increasing contact *** influences of the pipe diameter and contactangle difference on the pressure drop difference of JLHW105 oil showed an inversely proportional relation.A series of materials and liquids were *** selection of pipe material for transporting a given fluid can be based on the contact angle,surface tension,and critical limit of the contact angle *** research results are expected to provide some guidelines for the selection of the appropriate pipe material for a given set of fluids.

关键词： Wettability Contact angle Frictional coefficient Fluid mechanics Laminar flow Petroleum

DISTRIBUTED OPTICAL FIBER SENSOR FOR LONg-DISTANCE OIL PIPELINE HEALTH

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Chinese Journal of Mechanical Engineering 2006年第1期19卷 137-139页

作者： WANg Yannian JIANg Zhuangde CHEN xiaonan ZHAO yulong State Key Laboratory for Manufacturing Systems Engineering Xi＇ an Jiaotong University Xi＇ an 710049 China Institute of Precision Engineering Xi＇ an Jiaotong University Xi＇ an 710049 China

A fully distributed optical fiber sensor （DOFS） for monitoring long-distance oil pipeline health is proposed based on optical time domain reflectometry （OTDR）. A smart and sensitive optical fiber cable is installed along the pipeline acting as a sensor, The experiments show that the cable swells when exposed to oil and induced additional bending losses inside the fiber, and the optical attenuation of the fiber coated by a thin skin with periodical hardness is sensitive to deformation and vibration caused by oil leakage, tampering, or mechanical impact. The region where the additional attenuation occurred is detected and located by DOFS based on OTDR, the types of pipeline accidents are identified according to the characteristics of transmitted optical power received by an optical power meter, Another prototype of DOFS based on a forward traveling frequency-modulated continuous-wave （FMCW） is also proposed to monitor pipeline. The advantages and disadvantages of DOFSs based on OTDR and FMCW are discussed. The experiments show that DOFSs are capable of detecting and locating distant oil pipeline leakages and damages in real time with an estimated precision of ten meters over tens of kilometers.

关键词： Optical fiber sensor Fault diagnostic Leak detection Oil pipeline

局部枸橼酸抗凝在连续肾脏替代疗法串联人工肝治疗中的运用效果观察

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实用医学杂志 2024年第13期40卷 1879-1884页

作者：金玉峰申存毅张靖垚薛玉龙何栋西安交通大学第一附属医院西安710061

目的观察局部枸橼酸抗凝(regional citrate anticoagulation,RCA)在连续肾脏替代疗法(continuous renal replacement therapy,CRRT)串联人工肝治疗中的运用效果和安全性。方法收集2019年12月至2023年6月我中心收治的21例慢加急性肝衰竭(acute on chronic liver failure,ACLF)合并急性肾损伤(acute kidney injury,AKI)的患者行RCA的CRRT串联人工肝治疗54例次的临床资料,观察分析治疗前后肝肾功能指标改善情况、枸橼酸的抗凝效果和不良反应以及患者转归。结果54例次的CRRT串联人工肝治疗前后肝肾功能指标均有改善,差异有统计学意义(P0.05);但其中3例次CRRT串联PE和1例次CRRT串联DPMAS+LPE的患者治疗后发生枸橼酸蓄积,通过及时纠正和补充24 h后均恢复正常;21例患者30 d生存率:存活13例,死亡5例,自动出院3例。结论在严密监测和及时调整的情况下RCA在CRRT串联人工肝治疗中的运用安全可行,值得临床推广。

关键词：慢加急性肝衰竭急性肾损伤枸橼酸人工肝连续性肾脏替代疗法

Core-shell structured Co@NC@MoS_(2)magnetic hierarchical nanotubes:Preparation and microwave absorbing properties

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Journal of Materials Science & Technology 2022年第33期128卷 148-159页

作者： Yunfei Zhang yulong Li Mengmeng Wei Dengtao Yang Qiuyu Zhang Baoliang Zhang School of Chemistry and Chemical Engineering Northwestern Polytechnical UniversityXi’an 710072China xi’an Key Laboratory of Functional Organic Porous Materials Northwestern Polytechnical UniversityXi’an 710129China Shaanxi Engineering and Research Center for Functional Polymers on Adsorption and Separation Sunresins New Materials Co.Ltd.Xi’an 710072China

In this study,a new lightweight one-dimensional absorber Co@NC@MoS_(2)was designed and ***,polydopamine(PDA)was coated by oxidative self-polymerization with cobalt-nitrilotriacetic acid chelate nanowires(Co-NTAC)as *** core-shell structured magnetic hierarchical nanotubes(Co@PDA@MoS_(2))were prepared by one-step hydrothermal *** thermal annealing,PDA layer was transformed into nitrogen doped carbon layer(NC)to obtain the efficient microwave absorber Co@NC@MoS_(2).The removal of template and growth of MoS_(2)were completed simultaneously,the preparation process was *** of its good magnetic loss and dielectric loss,Co@NC@MoS_(2)shows excellent microwave absorption *** filler content of 15 wt.%,the minimum reflection loss(RL_(min))can reach-61.97 dB@9.2 gHz,and the effective absorption bandwidth(EAB)is 5.6 *** electromagnetic parameters of Co@NC@MoS_(2)can be further adjusted by changing the load of MoS_(2).Meanwhile,the structure and composition of Co@NC@MoS_(2)were systematically *** influence of the microstructure on the microwave absorbing properties was investigated,and the microwave attenuation mechanism is *** an efficient and lightweight absorber,Co@NC@MoS_(2)has potential application value in the construction of new stealth coatings.

关键词： Nanotubes Magnetic materials Core-shell structure MoS_(2)nanosheets Electromagnetic wave absorption

Temperature Effect on the Mechanical Behavior of Acrylic Polymers under Quasi-static and Dynamic Loading

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上海交通大学学报 2004年第Z2期38卷 89-95页

作者： Tao Suo yulong Li Hong Yu Fei Xu Zhongbin Tang Lei Li School of Aeronautics Northwestern Polytechnical University Xi''an710072 China School of Aeronautics Northwestern Polytechnical University Xi''an710072 China School of Aeronautics Northwestern Polytechnical University Xi''an710072 China School of Aeronautics Northwestern Polytechnical University Xi''an710072 China School of Aeronautics Northwestern Polytechnical University Xi''an710072 China Beijing Institute of Aeronautical Materials Beijing100095China

In this paper, the mechanical behavior of acrylic polymers at elevated temperature was investigated. Four acrylic polymers were tested at high strain rate by using compression Hopkinson bar and at quasi-static strain rate by using an Instron servo hydraulic axial testing machine with the testing temperature from 218K to 393K. The results show that the mechanical property of acrylic polymers depends heavily on the testing temperature. The yield stress and Young's modulus were found to decrease with increasing temperature at low strain rate. At very low temperature, the materials display typical brittle fracture; however their plasticity improves remarkably at high temperatures. The predictions of the mechanical behavior including the effect of temperature and strain rate using a proposed theoretical model have a good agreement with experimental results.

关键词： acrylic polymer compression Hopkinson bar quasi-static dynamic fracture

Construction of Short-Block Nonbinary LDPC Codes Based on Cyclic Codes

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China Communications 2017年第8期14卷 1-9页

作者： Hengzhou Xu Baoming Bai Min Zhu Bo Zhang yulong Zhang School of Network Engineering Zhoukou Normal UniversityZhoukou 466001China State Key Laboratory of Integrated Service Networks Xidian UniversityXi'an 710071China Zhoukou Hydrology and Water Resoures Survey Bureau of Henan Province Zhoukou 466001China

In this paper, we focus on shortblock nonbinary LDPC(NB-LDPC) codes based on cyclic codes. Based on Tanner graphs' isomorphism, we present an efficient search algorithm for finding non-isomorphic binary cyclic LDPC codes. Notice that the parity-check matrix H of the resulting code is square and not of full rank, and its row weight and column weight are the same. By replacing the ones in the same column of H with a nonzero element of fi nite fi elds gF(q), a class of NB-LDPC codes over gF(q) is obtained. Numerical results show that the constructed codes perform well over the AWgN channel and have fast decoding convergence. Therefore, the proposed NB-LDPC codes provide a promising coding scheme for low-latency and high-reliability communications.

关键词： nonbinary LDPC codes tanner graph isomorphism iterative decoding