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喷淋作用下的深水测试放喷热辐射规律及关键参数

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天然气工业 2024年第2期44卷 111-121页

作者：孙巧雷刘语维张崇夏乐冯定邓龙任冠龙董钊长江大学机械工程学院湖北省油气钻完井工具工程技术研究中心中海石油(中国)有限公司湛江分公司

在深水天然气测试过程中,多相混合物会通过地面流程分离、泄压、加热后通过燃烧臂放喷燃烧,现场一般采用喷淋的方式来降低热辐射的影响。为了降低深水放喷测试作业时平台及燃烧臂的热辐射风险隐患,首先采用Thornton模型研究了火焰表面... 详细信息

在深水天然气测试过程中,多相混合物会通过地面流程分离、泄压、加热后通过燃烧臂放喷燃烧,现场一般采用喷淋的方式来降低热辐射的影响。为了降低深水放喷测试作业时平台及燃烧臂的热辐射风险隐患,首先采用Thornton模型研究了火焰表面辐射能量、视角系数以及水幕透射率等参数,构建了喷淋作用下放喷火焰的热辐射通量计算模型,并结合现场燃烧放喷下的仿真模型,应用有限元软件分析了放喷喷淋影响下的火焰温度和辐射量变化规律。研究结果表明:(1)喷淋形成的水幕使靠近平台区域的温度和辐射量明显降低,放喷管道附近的辐射量由2 050 W/m^(2)减小到了1 840 W/m^(2);(2)在单个水幕的作用下,水幕吸收了一定的热辐射量,水幕温度从11.85℃上升到约26.85℃;(3)由于平台附近的空气中CO_(2)和H_(2)O含量较低,空气的热辐射吸收系数较小,温度主要受到热对流的影响,空气温度基本保持在26.85~36.15℃之间;(4)不同放喷管径和产量变化下平台附近区域的温度和辐射量变化趋势基本一致,管径减小使得辐射峰值增大。结论认为,该研究成果进一步明确了深水测试放喷不同工况下的热辐射分布,为深水地面放喷热辐射设计分析及安全控制提供了技术支撑。

关键词：深水测试放喷燃烧嘴喷淋作用辐射温度辐射量辐射分布燃烧

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Quantum Stackelberg Duopoly Game in Depolarizing Channel

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Communications in Theoretical Physics 2008年第1期49卷 111-116页

作者： ZHU xia KUANG le-Man Department of Physics Hunan Normal University Changsha 410081 China

In this paper, we investigate the quantum Stackelberg duopoly （QSD） game in the noise environment with the depolarizing channel expressed by the Kraus-operator representation. It is found that the presence of the damping in the depolarizing channel always leads to the decrease of the quantities of the moves and payoffs of the two players in the QSD game. It is indicated that under certain conditions the first-mover advantage in the QSD game can be weakened due to the presence of the damping in the depolarizing channel.

关键词： quantum Stackelberg duopoly game Kraus operators depolarizing channel

壳聚糖改性生物炭的制备及其对水溶液中Cd^(2+)的吸附机制

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环境科学 2024年第2期45卷 873-884页

作者：姜凌安靖玥岳小琼李亚雄夏秋乐祝婷文佳柴丽红长安大学水利与环境学院西安710054 长安大学旱区地下水文与生态效应教育部重点实验室西安710054 长安大学土地工程学院西安710054

以猕猴桃枝为原料,壳聚糖作为胺基表面改性剂,制备了一种绿色环保、对环境中重金属有良好吸附效果的功能性生物炭材料.采用批量吸附实验研究了改性前后生物炭的吸附性能.借助SEM-EDS、FTIR和XPS表征方法,分析了改性前后生物炭的形貌结... 详细信息

以猕猴桃枝为原料,壳聚糖作为胺基表面改性剂,制备了一种绿色环保、对环境中重金属有良好吸附效果的功能性生物炭材料.采用批量吸附实验研究了改性前后生物炭的吸附性能.借助SEM-EDS、FTIR和XPS表征方法,分析了改性前后生物炭的形貌结构和官能团变化,探究了其对溶液中Cd^(2+)的吸附机制.结果表明,改性后的生物炭表面,引入了羟基(—OH)、羰基(—C=O)和氨基(—NH_(2))等基团,显著提高了吸附性能,对Cd^(2+)的吸附量较改性前增加107.12%.Lagergren准二级动力学模型和Langmuir等温吸附方程能较好地描述吸附过程,说明吸附速率由材料表面活性位点决定,吸附过程以化学吸附为主.对Cd^(2+)的吸附机制主要是配位作用、表面沉淀作用、离子交换作用和阳离子—π键作用,吸附过程为自发的吸热过程.经过5次吸附-解吸循环后,改性后生物炭对Cd^(2+)的吸附容量仍保持在初始吸附量的80%以上,表现出良好的可重复利用性.研究成果体现绿色化学的理念,所制备的壳聚糖改性生物炭可应用于镉污染水体和土壤的修复.

关键词：生物炭壳聚糖吸附剂镉(Cd)污染吸附机制

GH_2 Control for Uncertain Discrete-time-delay Fuzzy Systems Based on a Switching Fuzzy Model and Piecewise Lyapunov Function

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International Journal of Automation and computing 2009年第3期6卷 261-266页

作者： Zhi-le xia Jun-Min Li School of Science Xidian University Xi＇an 710071 PRC School of Mathematics and Information Engineering Taizhou University Taizhou 317000 PRC

Generalized H2 （GH2） stability analysis and controller design of the uncertain discrete-time Takagi-Sugeno （T-S） fuzzy systems with state delay are studied based on a switching fuzzy model and piecewise Lyapunov function. GH2 stability sufficient conditions are derived in terms of linear matrix inequalities （LMIs）. The interactions among the fuzzy subsystems are considered. Therefore, the proposed conditions are less conservative than the previous results. Since only a set of LMIs is involved, the controller design is quite simple and numerically tractable. To illustrate the validity of the proposed method, a design example is provided.

关键词： Generalized H2 (GH2) control fuzzy systems linear matrix inequalities (LMIs) piecewise Lyapunov function switchingfuzzy model.

深水测试密闭环空压力变化下的封隔器胶筒性能分析

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润滑与密封 2024年第4期49卷 147-153页

作者：孙巧雷夏乐刘语维冯定侯灵霞邓龙长江大学机械工程学院湖北荆州434000 湖北省油气钻完井工具工程技术研究中心湖北荆州434000

为探讨深水测试双封隔器由密闭环空压力变化引起的变形与强度问题,建立双封隔器胶筒结构的力学分析模型。根据工作过程中封隔器间密闭环空压力的变化,对胶筒的密封性能进行分析,得到各胶筒的应变量、等效应力以及接触应力的变化情况。... 详细信息

为探讨深水测试双封隔器由密闭环空压力变化引起的变形与强度问题,建立双封隔器胶筒结构的力学分析模型。根据工作过程中封隔器间密闭环空压力的变化,对胶筒的密封性能进行分析,得到各胶筒的应变量、等效应力以及接触应力的变化情况。分析采用胶筒不同圆形倒角参数时封隔器胶筒与套管的接触特性,研究胶筒倒角参数对封隔器密封性能的影响,得出封隔器的优化结构参数。结果显示:各胶筒的应变量、等效应力以及接触应力均随密闭环空压力的增大而增大,其中下胶筒的增大幅度最明显;各胶筒变形量随着胶筒倒角的增大无明显变化,但等效应力随着胶筒倒角的增大均减小,而随着胶筒倒角的增大上胶筒和中胶筒的接触应力均增大,下胶筒的接触应力先增大后减小。因此,一定程度上增大胶筒倒角有利于提升封隔器的密封性能,倒角半径为0.75 mm时为最优结构。

关键词：双封隔器密闭环空密封性能强度接触应力

Bilateral swap agreement and renminbi settlement in cross-border trade

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Economic and Political Studies 2020年第3期8卷 355-373页

作者： Ke Song le xia China Financial Policy Research Centre School of FinanceRenmin University of ChinaBeijingChina International Monetary Institute Renmin University of ChinaBeijingChina

This research empirically examines the impact of China’s renminbi(RMB)Bilateral Swap Agreements(BSAs)on the usage of the currency in cross-border trade *** using a unique dataset from SWIFT including cross-border settlement messages of 91 countries/regions between October 2010 and November 2015,we confirm that the signing of an RMB BSA helps increase the number,value and proportion of the RMB settlement in cross-border *** results are robust with respect to the choice of different models,including multi-level mixed model,two-stage regression model,and difference-in-difference *** addition to justifying the effectiveness of China’s BSA-signing strategy to promote the RMB usage in trade settlement,our results clarify that the signing of those RMB BSAs is not purely for China’s political ends as some scholars claim.

关键词： RMB bilateral swap agreement cross-border trade SWIFT

Self-healing Polymeric Hydrogels:Toward Multifunctional Soft Smart Materials

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Chinese Journal of Polymer Science 2021年第10期39卷 1262-1280,I0006页

作者： xiao-Ling Zuo Shao-Fan Wang xiao-xia le Wei Lu Tao Chen College of Materials Science and Engineering Guizhou Minzu UniversityGuiyang 550025China Key Laboratory of Bio-Based Polymeric Materials Technology and Application of Zhejiang Province Ningbo Institute of Material Technology and EngineeringChinese Academy of SciencesNingbo 315201China School of Chemical Sciences University of Chinese Academy of SciencesBeijing 100049China

The concept of self-healing that involves a built-in ability to heal in response to damage wherever and whenever it occurs in a material,analogous to the healing process in living organisms,has emerged a couple of decades *** primarily by the demands for life-like materials and soft smart materials,therefore,the development of self-healing polymeric hydrogels has continually attracted the attention of the scientific ***,this review is intended to give an in-depth overview of the state-of-the-art advances in the field of self-healing polymeric ***,recently emerging trends in self-healing polymeric hydrogels are summarized,and notably,recommendations to endow these hydrogels with fascinating multi-functionalities including luminescence,conductivity/magnetism and shape memory etc are *** close,the current challenges and future opportunities in this field are also discussed.

关键词： Polymeric hydrogels Self-healing Multi-functionalities Smart materials

间隙原子及颗粒对激光增材制造高熵合金微观结构与力学性能影响的研究进展

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航空制造技术 2024年第8期67卷 54-63,75页

作者：高宏亮苏海军郭一诺杨培鑫夏乐张卓郭敏西北工业大学深圳研究院深圳518057 西北工业大学材料学院西安710072

近年来,高熵合金(HEAs)由于其独特的多主元设计理念和优异的性能获得了研究者的广泛关注。激光增材制造能够获得具有超细晶和多尺度结构的高熵合金,使其具有优异的力学性能。同时间隙原子的掺杂及增强颗粒的添加有助于进一步改善合金的... 详细信息

近年来,高熵合金(HEAs)由于其独特的多主元设计理念和优异的性能获得了研究者的广泛关注。激光增材制造能够获得具有超细晶和多尺度结构的高熵合金,使其具有优异的力学性能。同时间隙原子的掺杂及增强颗粒的添加有助于进一步改善合金的强塑性,在航空航天高性能结构材料等领域应用前景开阔。基于此,首先介绍了选区激光熔化技术和激光定向能量沉积技术的原理和特点;然后,总结了间隙原子(C、B、N)及增强颗粒对激光增材制造高熵合金微观组织及力学性能的影响,并分析了各个间隙原子及增强颗粒对合金的强塑化机理;最后对激光增材制造高强塑性高熵合金的发展前景做了展望。

关键词：激光增材制造高熵合金间隙原子增强颗粒微观组织力学性能

Delay-dependent Non-fragile H_∞ Filtering for Uncertain Fuzzy Systems Based on Switching Fuzzy Model and Piecewise Lyapunov Function

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International Journal of Automation and computing 2010年第4期7卷 428-437页

作者： Zhi-le xia Jun-Min Li Jiang-Rong Li School of Science Xidian University Xi＇an 710071 PRC School of Mathematics and Information Engineering Taizhou University Taizhon 2317000 PRC College of Mathematics and Computer Science Yanan University Yanan 716000 PRC

This paper is concerned with the non-fragile H∞ filter design problem for uncertain discrete-time Takagi-Sugeno （T-S） fuzzy systems with time delay. To begin with, the T-S fuzzy system is transformed to an equivalent switching fuzzy system. Then, based on the piecewise Lyapunov function and matrix decoupling technique, a new delay-dependent non-fragile H∞ filtering method is proposed for the switching fuzzy system. The proposed condition is less conservative than the previous results. Since only a set of LMIs is involved, the filter parameters can be solved directly. Finally, a design example is provided to illustrate the validity of the proposed method.

关键词： Non-fragile H∞ filter delay-dependent piecewise Lyapunov function linear matrix inequalities (LMIs)