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Tsallis holographic dark energy under complex form of quintessence model
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作者 J Sadeghi S Noori Gashti T Azizi 《Communications in Theoretical Physics》 SCIE CAS CSCD 2023年第2期157-167,共11页
In this paper,we use a Tsallis holographic dark energy model in two forms,interacting and noninteracting cases,to acquire some parameters as the equation of state for the energy density of the Tsallis model in the FRW... In this paper,we use a Tsallis holographic dark energy model in two forms,interacting and noninteracting cases,to acquire some parameters as the equation of state for the energy density of the Tsallis model in the FRW Universe concerning the complex form of quintessence model.We will study the cosmology of complex quintessence by revamping the potential and investigating the scalar field dynamics.Then we analyze(w-w’)and stability in two cases,i.e.noninteracting and interacting.We will explore whether these cases describe a real Universe by calculating fractional energy densityΩ_(D)and concerning two parts of the quintessence field effect(complex and real part)by considering the real part of this field to be a slow-roll field.We know that the part in which the fractional energy density(Ω_(D)>1)does not describe a real Universe.Also,we specified an interacting coupling parameter b2that depends on the constant parameter of the Tsallis holographic model(δ)with respect to fractional energy density(0.73).Unlike independence between the fractional energy density and interacting coupling in the real quintessence model,we determine a relationship among these parameters in this theory.Finally,by plotting some figures,we specify the features of(w-w’)and(ν^(2)_(s))in two cases and compare the result with each other. 展开更多
关键词 Tsallis holographic model complex form of quintessence model STABILITY
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SLANT IMMERSIONS OF COMPLEX SPACE FORMS AND CHEN'S INEQUALITY 被引量:10
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作者 李光汉 吴传喜 《Acta Mathematica Scientia》 SCIE CSCD 2005年第2期223-232,共10页
A submanifold in a complex space form is called slant if it has constant Wirtinger angles. B. Y. Chen and Y. Tazawa proved that there do not exist minimal proper slant surfaces in CP2 and CH2. So it seems that the sla... A submanifold in a complex space form is called slant if it has constant Wirtinger angles. B. Y. Chen and Y. Tazawa proved that there do not exist minimal proper slant surfaces in CP2 and CH2. So it seems that the slant immersion has some interesting properties. The authors have great interest to consider slant immersions satisfying some additional conditions, such as unfull first normal bundles or Chen’s equality holding. They prove that there do not exist n-dimensional Kaehlerian slant immersions in CPn and CHn with unfull first normal bundles. Next, it is seen that every Kaehlerian slant submanifold satisfying an equality of Chen is minimal which is similar to that of Lagrangian immersions. But in contrast, it is shown that a large class of slant immersions do not exist thoroughly. Finally, they give an application of Chen’s inequality to general slant immersions in a complex projective space, which generalizes a result of Chen. 展开更多
关键词 Slant immersion IDEAL Chen's inequality complex space form
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Simulating Some Complex Phenomena in Hydrothermal Ore-Forming Processes by Reaction-Diffusion CNN 被引量:1
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作者 Xu Deyi Yu Chongwen Bao Zhengyu Geochemistry Institute, China University of Geosciences, Wuhan 430074 《Journal of China University of Geosciences》 SCIE CSCD 2003年第3期215-219,共5页
Complexity phenomena like dynamic and static patterns, order from disorder, chaos and catastrophe were simulated by the application of 2-D reaction-diffusion CNN of two state variables and two diffusion coefficients t... Complexity phenomena like dynamic and static patterns, order from disorder, chaos and catastrophe were simulated by the application of 2-D reaction-diffusion CNN of two state variables and two diffusion coefficients transformed from Zhabotinksii model. They revealed somehow the mechanism of hydrothermal ore-forming processes, and answered several questions about the onset of ore forming. 展开更多
关键词 hydrothermal ore forming complexity reaction-diffusion CNN
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KOPPELMAN-LERAY FORMULA ON COMPLEX MANIFOLDS 被引量:1
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作者 钟同德 《Acta Mathematica Scientia》 SCIE CSCD 1995年第1期90-94,共5页
The Koppelman-Leray formula on complex manifolds is obtained, and under suitable condition the continuous solution of partial derivative-equation on complex manifolds is obtained.
关键词 complex MANIFOLDS CHERN form KOPPELMAN-LERAY formULA PARTIAL-DERIVATIVE-EQUATION
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COMPLEX INNER PRODUCT AVERAGING METHOD FOR CALCULATING NORMAL FORM OF ODE 被引量:1
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作者 CHEN Yu-shu(陈予恕) +1 位作者 SUN Hong-jun(孙洪军) 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2001年第12期1368-1374,共7页
This paper puts forward a complex inner product averaging method for calculating normal form of ODE. Compared with conventional averaging method, the theoretic analytical process has such simple forms as to realize co... This paper puts forward a complex inner product averaging method for calculating normal form of ODE. Compared with conventional averaging method, the theoretic analytical process has such simple forms as to realize computer program easily. Results can be applied in both autonomous and non-autonomous systems. At last, an example is resolved to verify the method. 展开更多
关键词 nonlinear dynamic system normal form complex inner product averaging method
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Chen's Inequalities for Totally Real Submanifolds in Complex Space Forms with a Semi-Symmetric Metric Connection
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作者 Pan ZHANG Liang ZHANG Weidong SONG 《Journal of Mathematical Research with Applications》 CSCD 2014年第5期587-596,共10页
In this paper, we obtain Chen's inequalities for totally real submanifolds in complex space forms with a semi-symmetric metric connection. Also, some results of A. Mihai and C. Ozgiir's paper have been modified.
关键词 Chen's inequalities complex space forms totally real submanifolds semi-symmetricmetric connection.
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RIGIDITY THEOREMS OF COMPLETE K?HLER-EINSTEIN MANIFOLDS AND COMPLEX SPACE FORMS
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作者 Tian CHONG Yuxin DONG +1 位作者 Hezi LIN Yibin REN 《Acta Mathematica Scientia》 SCIE CSCD 2019年第2期339-356,共18页
We concentrate on using the traceless Ricci tensor and the Bochner curvature tensor to study the rigidity problems for complete K?hler manifolds. We derive some elliptic differential inequalities from Weitzenb?ck form... We concentrate on using the traceless Ricci tensor and the Bochner curvature tensor to study the rigidity problems for complete K?hler manifolds. We derive some elliptic differential inequalities from Weitzenb?ck formulas for the traceless Ricci tensor of K?hler manifolds with constant scalar curvature and the Bochner tensor of K?hler-Einstein manifolds respectively. Using elliptic estimates and maximum principle, several L^p and L~∞ pinching results are established to characterize K?hler-Einstein manifolds among K?hler manifolds with constant scalar curvature and complex space forms among K?hler-Einstein manifolds.Our results can be regarded as a complex analogues to the rigidity results for Riemannian manifolds. Moreover, our main results especially establish the rigidity theorems for complete noncompact K?hler manifolds and noncompact K?hler-Einstein manifolds under some pointwise pinching conditions or global integral pinching conditions. To the best of our knowledge,these kinds of results have not been reported. 展开更多
关键词 rigidity theorems Kahler-Einstein complex space forms
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Crystalline inclusion complexes formed between the drug diflunisal and block copolymers
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作者 Zhi Zhong Xiaotong Yang +4 位作者 Xiao-Bin Fu Ye-Feng Yao Bao-Hua Guo Yanbin Huang Jun Xu 《Chinese Chemical Letters》 SCIE CAS CSCD 2017年第6期1268-1275,共8页
The solid form of drugs plays a central role in optimizing the physicochemical properties of drugs,and new solid forms will provide more options to achieve the desirable pharmaceutical profiles of drugs.Recently,certa... The solid form of drugs plays a central role in optimizing the physicochemical properties of drugs,and new solid forms will provide more options to achieve the desirable pharmaceutical profiles of drugs.Recently,certain drugs have been found to form crystalline inclusion complexes(ICs) with multiple types of linear polymers,representing a new subcategory of pharmaceutical solids.In this study,we used diflunisal(DIF) as the model drug host and extended the vip of drug/polymer ICs from homopolymers to block copolymers of poly(ethylene glycol)(PEG) and poly(s-caprolactone)(PCL).The block length in the vip copolymers showed a significant influence on the formation,thermal stability and dissolution behavior of the DIF ICs.Though the PEG block could hardly be included alone,it could indeed be included in the DIF ICs when the PCL block was long enough.The increase of the PCL block length produced IC crystals with improved thermal stability.The dissolution profiles of DIF/block copolymer ICs exhibited gradually decreased aqueous solubility and dissolution rate with the increasing PCL block length.These results demonstrate the possibility of using drug/polymer ICs to modulate the desired pharmaceutical profiles of drugs in a predictable and controllable manner. 展开更多
关键词 Pharmaceutical solid forms Inclusion complexes Drugs Block copolymers Thermal stability Aqueous solubility Dissolution profiles
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Commuting Structure Jacobi Operator for Real Hypersurfaces in Complex Space Forms
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作者 U-Hang Ki Hiroyuki Kurihara 《Advances in Pure Mathematics》 2013年第2期264-276,共13页
Let M be a real hypersurface of a complex space form with almost contact metric structure (φ,ξ,η,g). In this paper, we prove that if the structure Jacobi operator Rξ=(·,ξ) ξ is φ▽ξξ-parallel and Rξ com... Let M be a real hypersurface of a complex space form with almost contact metric structure (φ,ξ,η,g). In this paper, we prove that if the structure Jacobi operator Rξ=(·,ξ) ξ is φ▽ξξ-parallel and Rξ commute with the shape operator, then M is a Hopf hypersurface. Further, if Rξ is φ▽ξξ-parallel and Rξ commute with the Ricci tensor, then M is also a Hopf hypersurface provided that TrRξ is constant. 展开更多
关键词 complex Space form Hopf HYPERSURFACE STRUCTURE JACOBI OPERATOR Shape OPERATOR RICCI Tensor
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Drug-polymer inclusion complex as a new pharmaceutical solid form
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作者 Xiaotong Yang Zhi Zhong +1 位作者 Jun Xu Yanbin Huang 《Chinese Chemical Letters》 SCIE CAS CSCD 2017年第11期2099-2104,共6页
The solid forms of drugs play a central role in controlling their physicochemical properties and consequently the bioavailability. Multiple types of drug solid forms have been developed to achieve the desirable pharma... The solid forms of drugs play a central role in controlling their physicochemical properties and consequently the bioavailability. Multiple types of drug solid forms have been developed to achieve the desirable pharmaceutical profiles, but new solid forms will provide more options for the solid-state property optimization and hence are highly desirable. This review focuses on a new pharmaceutical solid form, drug-polymer inclusion complexes (ICs), and summarizes their structural features, structure- property relationships, as well as potential pharmaceutical applications 展开更多
关键词 Pharmaceutical solid forms Crystalline inclusion complex Thermal stability Dissolution profiles Homopolymers Block copolymers
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Residues of Logarithmic Differential Forms in Complex Analysis and Geometry
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作者 A.G.Aleksandrov 《Analysis in Theory and Applications》 2014年第1期34-50,共17页
In the article, we discuss basic concepts of the residue theory of logarithmic and multi-logarithmic differential forms, and describe some aspects of the theory, de-veloped by the author in the past few years. In part... In the article, we discuss basic concepts of the residue theory of logarithmic and multi-logarithmic differential forms, and describe some aspects of the theory, de-veloped by the author in the past few years. In particular, we introduce the notion of logarithmic differential forms with the use of the classical de Rham lemma and give an explicit description of regular meromorphic differential forms in terms of residues of logarithmic or multi-logarithmic differential forms with respect to hypersurfaces, com-plete intersections or pure-dimensional Cohen-Macaulay spaces. Among other things, several useful applications are considered, which are related with the theory of holo-nomic D-modules, the theory of Hodge structures, the theory of residual currents and others. 展开更多
关键词 Logarithmic differential forms de Rham complex regular meromorphic forms holo-nomic D-modules Poincare lemma mixed Hodge structure residual currents.
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ON THE DECOMPOSITION OF COMPLEX VECTOR SPACES AND THE JORDAN CANONICAL FORM OF COMPLEX LINEAR TRANSFORMATIONS
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作者 肖衡 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 1994年第11期997-1003,共7页
New objects characterizing the structure of complex linear transformations areintroduced. These new objects yield a new result for the decomposition of complexvector spaces relative to complex lrnear transformations a... New objects characterizing the structure of complex linear transformations areintroduced. These new objects yield a new result for the decomposition of complexvector spaces relative to complex lrnear transformations and provide all Jordan basesby which the Jordan canonical form is constructed. Accordingly, they can result in thecelebrated Jordan theorem and the third decomposition theorem of space directly. and,moreover, they can give a new deep insight into the exquisite and subtle structure ofthe Jordan form. The latter indicates that the Jordan canonical form of a complexlinear transformation is an invariant structure associated with double arbitrary. choices. 展开更多
关键词 complex vector space complex linear transformation. decompo-sition theorems. Jordan canonical form
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A method for calculation of ion distribution in reaction system forming hydroxide
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作者 金哲男 郑大录 +3 位作者 洪正秀 郑英勋 路殿坤 陈国宝 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2013年第12期3793-3798,共6页
A formula was proposed to calculate the distribution of metal ions quantitatively in chemical reaction system forming hydroxide where precipitation and complex are formed together. The effects of some factors on forma... A formula was proposed to calculate the distribution of metal ions quantitatively in chemical reaction system forming hydroxide where precipitation and complex are formed together. The effects of some factors on formation of precipitation and complex were investigated, and the corresponding precipitation rates of zinc, iron (III), aluminum, copper and magnesium were calculated. As a result, it shows that the proposed formula is reliable. By the proposed formula, the existence state of metal ions in hydroxides reaction system with any metal ions can be well described and the effects of some factors on the distribution of metal ions were determined. 展开更多
关键词 HYDROXIDE metal ions distribution precipitation rate complex forming rate
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19世纪英国小说中的阶级形态
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作者 陈珍 《鲁东大学学报(哲学社会科学版)》 2026年第1期9-15,共7页
19世纪的英国小说形象生动地反映了当时英国的社会现实和阶级形态。19世纪英国社会变革动摇了固有的社会形态和阶级结构,资本成为衡量阶级层次的价值尺度,中产阶级势力逐渐壮大,贵族势力日渐式微,工人阶级亦存在上升空间,阶级层次呈现... 19世纪的英国小说形象生动地反映了当时英国的社会现实和阶级形态。19世纪英国社会变革动摇了固有的社会形态和阶级结构,资本成为衡量阶级层次的价值尺度,中产阶级势力逐渐壮大,贵族势力日渐式微,工人阶级亦存在上升空间,阶级层次呈现上下流动态势,阶级身份随之起伏变化。19世纪30年代后,阶级形态尤其呈现出明显的流动性、复杂性、多样性,并由此引起人物身份危机和心理困惑。通过对19世纪英国小说的分析可以看出,阶级形态既有宏观上的社会形态,又有微观上的个人形态,既有社会历史根源,又有个人家庭原因。 展开更多
关键词 阶级形态 流动性 复杂性 多样性 身份危机
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基于MBSE的复杂成形装备概念设计方法
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作者 王博雅 王绍宗 +3 位作者 杨万然 周兴炜 侯亮 熊成悦 《图学学报》 北大核心 2026年第1期179-193,共15页
复杂成形装备的传统研制方式通常采用基于文档的系统工程(DBSE)方法开展,存在需求分析不完善导致研发缓慢、文本二义性导致需求覆盖不全、装备进展落后于技术迭代等问题,造成设计出的复杂成形装备存在设计指标不满足使用要求、反复修改... 复杂成形装备的传统研制方式通常采用基于文档的系统工程(DBSE)方法开展,存在需求分析不完善导致研发缓慢、文本二义性导致需求覆盖不全、装备进展落后于技术迭代等问题,造成设计出的复杂成形装备存在设计指标不满足使用要求、反复修改致使设计效率低下等问题。因此,在复杂成形装备概念设计阶段,参考美国国防部体系结构框架(DoDAF),结合基于模型的系统工程(MBSE),提出了基于MBSE的复杂成形装备概念设计方法。并以全景、能力、运行、系统及标准共5类视角作为复杂成形装备概念设计的切入点,通过多类视角切入分析开展复杂成形装备顶层需求获取、需求细化分析、功能分析及系统建模共4层级设计,并使用系统建模语言(SysML)建立起11种模型,实现复杂成形装备概念设计阶段的数字化和流程化表达。最后,以超塑成形装备作为典型实例进行设计方法的应用演示。通过实际应用解决了传统设计方式痛点问题,表明了方法对复杂成形装备的正向研制有良好的指导作用。 展开更多
关键词 复杂成形装备 MBSE DODAF SYSML 概念设计方法
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RESEARCH ON HOT FORMING PROCESS OF A RETAINING RING OF HIGH-NITROGEN STEEL 被引量:4
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作者 H.Q.Chen J.S.Liu H.G.Guo 《Acta Metallurgica Sinica(English Letters)》 SCIE EI CAS CSCD 2004年第5期767-770,共4页
Mn18Cr18N, the high-nitrogen steel, is the 2nd generation material for manufacturing the retaining ring of firepower generators. In this paper, the hot deformation behavior of the material was investigated by thermo-m... Mn18Cr18N, the high-nitrogen steel, is the 2nd generation material for manufacturing the retaining ring of firepower generators. In this paper, the hot deformation behavior of the material was investigated by thermo-mechanical modeling tests. And the flow stress curves of the steel were obtained for various combinations of the temperature and strain rate. Based on the results of the tests, the complex forming process of a retaining ring including punching, expanding and extrusion with an enclosure was put forward and simulated by means of numerical simulation method. The results indicate that the process is a novel and force-saved practical technology for manufacturing heavy retaining rings. 展开更多
关键词 Mn18Cr18N high-nitrogen steel a retaining ring the punching with an enclosure process expanding-extrusion complex forming
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Study on precision cutting technology of complex shape microparts
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作者 王贵林 张飞虎 戴一帆 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2007年第4期528-532,共5页
Relatively to non-traditional and high-energy-beam micro-manufacturing technique, the micro-cutting technology has many merits. For instance, the machining range is bigger, the cost of equipments is much lower, and th... Relatively to non-traditional and high-energy-beam micro-manufacturing technique, the micro-cutting technology has many merits. For instance, the machining range is bigger, the cost of equipments is much lower, and the productivity and machining accuracy are higher. Therefore, the micro-cutting technology will take an important effect on the machining technique of complex shape microparts. In this paper, based on selfly-developed machine tool, the precision cutting technology of complex shape microparts made of metal material was studied by analyzing the modeling method on complex shape, the means of toolpaths layout and the optimal selection for cutting parameters. On the basis of above work, a typical duralumin specimen of high precision, low surface roughness and complex shape micropart was manufactured. This result will provide favorable technical support for farther research on the micro-cutting technology. 展开更多
关键词 complex form microparts MOLDING CUTTING
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高强钢复杂特征板件辊压数值仿真分析
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作者 晏培杰 李丹阳 +1 位作者 郭宇彤 胡成亮 《锻压技术》 北大核心 2026年第3期73-81,共9页
为提升高强钢板辊压后的性能,围绕复杂特征板件辊压工艺展开研究,重点考察了阵列特征辊压成形工艺对板件变形行为的影响。该工艺在传统辊弯成形前,采用表面具有周期性阵列凸点的回转模具对板材进行局部塑性变形,在常温条件下实现材料强... 为提升高强钢板辊压后的性能,围绕复杂特征板件辊压工艺展开研究,重点考察了阵列特征辊压成形工艺对板件变形行为的影响。该工艺在传统辊弯成形前,采用表面具有周期性阵列凸点的回转模具对板材进行局部塑性变形,在常温条件下实现材料强化与结构预制。选取DP590和DP980两种典型双相钢作为研究对象,建立了考虑各向异性的本构模型,并基于有限元仿真系统,以咬合量为核心工艺参数,分析了成形过程中的应力、应变及厚度的变化规律。结果表明:两种材料在咬合量从原始板厚1/2增加至原始板厚时最大减薄区域的厚度均呈线性下降趋势,减薄幅度由约5%提升至约14%,成形后板材总厚度从原始板厚的1.5倍增加至2.6倍;模具所受纵向载荷和扭矩也随咬合量的增加呈线性增长趋势。进一步的工艺实验表明,仿真预测的厚度变化与实测结果误差在±5%以内,证明了有限元模型的有效性。研究结果对阵列特征辊压成形工艺的参数优化与模具设计具有重要参考价值。 展开更多
关键词 辊压成形 复杂特征板件 双相钢 咬合量 阵列特征
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复杂曲面复合材料成型模具加工研究
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作者 尤玉祥 《机械管理开发》 2026年第3期269-271,274,共4页
为了提升复杂曲面复合材料成型模具的加工精度与效率,通过介绍数控加工中的装夹方案设计、工艺参数确定、加工区域划分、刀具轨迹生成及后处理优化等关键环节,分析了模具在加工过程中的变形控制、机床可达性及轨迹精度等核心问题,提出... 为了提升复杂曲面复合材料成型模具的加工精度与效率,通过介绍数控加工中的装夹方案设计、工艺参数确定、加工区域划分、刀具轨迹生成及后处理优化等关键环节,分析了模具在加工过程中的变形控制、机床可达性及轨迹精度等核心问题,提出一种结合倾斜装夹、多阶段加工与动态步距控制的综合加工方法。研究结果表明:该方法能够有效提高刀具轨迹的一致性,减小加工偏差,提升模具型面精度与表面质量,为复杂曲面复合材料成型模具的高质量制造提供可靠的技术支持。 展开更多
关键词 复杂曲面 复合材料 成型 模具 加工 装夹方案
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燃料电池双极板冲压成形研究
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作者 覃业彬 唐昌悟 +1 位作者 解玄 吴桂勇 《模具工业》 2026年第2期28-33,共6页
燃料电池双极板冲压成形因高效、低成本、高材料利用率等优势正取代传统石墨加工与化学蚀刻,316L不锈钢冲压性能优于纯钛,其流道深度可达0.72 mm,纯钛仅0.53 mm且易破裂。经CrN涂层、激光微加工毛细孔及微凸起结构处理,燃料电池双极板... 燃料电池双极板冲压成形因高效、低成本、高材料利用率等优势正取代传统石墨加工与化学蚀刻,316L不锈钢冲压性能优于纯钛,其流道深度可达0.72 mm,纯钛仅0.53 mm且易破裂。经CrN涂层、激光微加工毛细孔及微凸起结构处理,燃料电池双极板接触电阻稳定于5~10 mΩ·cm^(2),腐蚀电流密度<1μA/cm^(2),排水效率提升40%。目前产业化瓶颈是0.05 mm超薄板冲压开裂及涂层2000 h后性能衰减>8%,未来需开发纳米晶合金、智能多轴冲压系统及梯度复合涂层,以突破高深宽比流道制造难题。 展开更多
关键词 冲压成形 双极板 表面处理 复杂流道
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