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基于Production Module 3D数控铣削仿真技术在钛合金主吊挂加工中的应用 被引量:2
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作者 吴东华 邓志刚 +2 位作者 张德纯 赵万岳 丁代华 《机械工程师》 2021年第11期149-152,155,共5页
在钛合金主吊挂支架的铣削过程中,采用Production Module 3D软件对数控程序、材料、刀具及工件的综合分析,得到了在整个数控程序下的温度峰值、进给力、切削力及材料去除率等数据。然后采用完善数控程序中的吃刀量、切削速度及进给量来... 在钛合金主吊挂支架的铣削过程中,采用Production Module 3D软件对数控程序、材料、刀具及工件的综合分析,得到了在整个数控程序下的温度峰值、进给力、切削力及材料去除率等数据。然后采用完善数控程序中的吃刀量、切削速度及进给量来使加工过程中温度、切削力等符合要求,使负载平衡,降低振动。最终刀具的使用寿命提高20%,加工周期降低22%。 展开更多
关键词 钛合金 铣削 Production module 3d
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Identification of the highly active Zn-N_(4) sites with pyrrole/pyridine-N synergistic coordination by dz^(2)+s-band center for electrocatalytic H_(2)O_(2) production
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作者 Rui Chen Wei Liu +11 位作者 Zhiyuan Sang Jingjing Jia Zhenxin Li Jiahuan Nie Qiao Jiang Zixian Mao Baitong Guo Qiuying Wang Feng Hou Lichang Yin De'an Yang Ji Liang 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第11期105-113,共9页
Single metal atoms anchored on nitrogen-doped carbon materials(M-N_(4))have been identified as effective active sites for catalyzing the two-electron oxygen reduction reaction(2e-ORR).However,the relationship between ... Single metal atoms anchored on nitrogen-doped carbon materials(M-N_(4))have been identified as effective active sites for catalyzing the two-electron oxygen reduction reaction(2e-ORR).However,the relationship between the local atomic/electronic environments of the M-N_(4) sites(metal atoms coordinated with different types of N species)and their catalytic activity for 2e-ORR has rarely been elaborated clearly,which imposes significant ambiguity for the rational design of catalysts.Herein,guided by the comprehensive density-functional theory calculations and predictions,a series of Zn-N_(4) single-atom catalysts(SACs)are designed with pyrrole/pyridine-N(N_(Po)/N_(Pd))synergistic coordination and prepared by controlling the pyrolysis temperature(600,700,and 800℃),Among them,the dominated Zn-N_(4) configurations with rationally combined N_(Po)/N_(Pd)coordination show~*OOH adsorption strength close to the optimal value,much superior to those with mono N species.Thus,the as-prepared catalyst exhibits a high H_(2)O_(2) selectivity of over 90%both in neutral and alkaline environments,with a superb H_(2)O_(2) yield of up to 33.63 mol g^(-1)h^(-1)in an alkaline with flow cell.More importantly,a new descriptor,dz^(2)+s band center,has been proposed,which is especially feasible for predicting the activity for metal types with fully occupied s and d orbitals.This work thus presents clear guidance for the rational design of highly active SACs toward ORR and provides a complement to the d-band theory for more accurately predicting the catalytic activity of the materials. 展开更多
关键词 Zinc single-atom catalysts Hydrogen peroxide Local coordination environments d+s-Band modulation
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Generalized braided Hopf algebras
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作者 LU Zhong-jian FANG Xiao-li 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2009年第1期105-113,共9页
The concept of (f, σ)-pair (B, H)is introduced, where B and H are Hopf algebras. A braided tensor category which is a tensor subcategory of the category ^HM of left H-comodules through an (f, σ)-pair is constr... The concept of (f, σ)-pair (B, H)is introduced, where B and H are Hopf algebras. A braided tensor category which is a tensor subcategory of the category ^HM of left H-comodules through an (f, σ)-pair is constructed. In particularly, a Yang-Baxter equation is got. A Hopf algebra is constructed as well in the Yetter-Drinfel'd category H^HYD by twisting the multiplication of B. 展开更多
关键词 (f σ )-pair Yetter-drinfel’d modules category braided Hopf algebra
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A simple 2D modulation code in single-reader two-track reading BPMR systems
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作者 Wiparat Busyatras Chanon Warisarn +1 位作者 Santi Koonkarnkhai Piya Kovintavewat 《Digital Communications and Networks》 SCIE CSCD 2021年第1期100-106,共7页
A reduction in the track width of magnetic recording systems results in a welcome increase in Areal Density(AD),but can severely deteriorate system performance in the unfortunate appearance of extreme Inter-Track Inte... A reduction in the track width of magnetic recording systems results in a welcome increase in Areal Density(AD),but can severely deteriorate system performance in the unfortunate appearance of extreme Inter-Track Interference(ITI).The effect of severe ITI may be mitigated by using coding schemes.In this paper,therefore,we present a rate-5/62-Dimensional(2D)modulation code based on a proposed Single-Reader/Two-track Reading(SRTR)technique to cope with this serious problem in staggered Bit-Pattemed Magnetic Recording(BPMR)systems.We then evaluate the Bit-Error Rate(BER)performance of the proposed system in the presence of media noises,e.g.,position and size fluctuations.Our simulation results indicate that,at the same User Density(UD),the proposed system performs better than an uncoded system by about 1.0 dB at the BER of 105 and is also superior to the conventional recording system. 展开更多
关键词 Bit-pattemed media recording 2d interference 2d modulation code Single-reader/two-track reading
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The Realization of Mass Customization Using Modularization Method
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作者 SU Ju-ning 1, YANG Shui-li 1, DONG Peng-fei 2 (1. School of Business Administration, Xi’an University of Technology, Xi’an 710048, China 2. Jinduicheng Molybdenum Mining Corporation, Huaxian 714102, China) 《厦门大学学报(自然科学版)》 CAS CSCD 北大核心 2002年第S1期244-,共1页
In the view of the comparison of Mass Customization ( MC) with Mass Production and Customization Production, the objectives of MC are analyzed. It is pointed out that the core objectives of MC are to realize in dividu... In the view of the comparison of Mass Customization ( MC) with Mass Production and Customization Production, the objectives of MC are analyzed. It is pointed out that the core objectives of MC are to realize in dividuation customization, low cost, quick response to market demands. The modul arization theory is simply introduced. Based on the characteristics of modular ization, the mechanism of realizing MC with modularization is analyzed. The in dividuation customization can be realized with the different combinations of mod ules. The low cost can be realized with the scale economy and the category econo my of modules. The quick response can be realized with standard modules and its interfaces. So, the modularization is a kind of effective method in realizing MC . The modularization for MC is a systems engineering. With product modularized, production organization and management and manufacturing equipment will be chang ed. In addition, the paper also proposes a Mass Customization production model w hich is based on modularization. This Mass Customization production model is con sisted of modularization of product design, specialization of manufacturing, Vir tual Enterprises based on modularizing enterprises, and modularizing manufacturi ng equipment. The module design for MC, modularizing enterprises, and reconfigur able automation manufacturing equipment are discussed, and it is pointed out tha t they are the important supports for MC. 展开更多
关键词 Mass Customization (MC) MOdULARIZATION module d esign modularizing enterprise reconfigurable automation manufacturing equipmen t
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THE EFFECT OF HOT DRAWN ON THE PHYSICAL AGING OF ATACTIC POLYSTYRENE
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作者 宋锐 林辛 +2 位作者 陈晶 高金贵 范庆荣 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 1998年第2期176-184,共9页
The physical aging behavior of atactic polystyrene (aPS) films achieved under different drawing conditions has been studied by optical birefringence and modulate differential scanning: calorimeter (m.d.s.c.). The resu... The physical aging behavior of atactic polystyrene (aPS) films achieved under different drawing conditions has been studied by optical birefringence and modulate differential scanning: calorimeter (m.d.s.c.). The results show that on annealing at specific temperature below glass transition temperatue (T-g), the enthalpy relaxation (Delta H) and T-g decrease with increasing of birefringence (Delta n). On the other baud, the effect of molecular draw ratio (MDR) is confusing: Delta H and T-g decrease with increasing of MDR in the early stage of aging, but the MDR's effect become unobvious with the development of aging. It may be concluded that the ordered domain generated by the drawing below or above glass transition temperature will affect the development of physical aging behavior. The viewpoint of cohesional entanglement is used to account for the above observations. 展开更多
关键词 modulated differential scanning calorimetry (m d.s.c.) atactic polystyrene physical aging EXTENSION ORIENTATION
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CVD Diamond Sink Application in High Power 3D MCMs
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作者 谢扩军 蒋长顺 李承跃 《Journal of Electronic Science and Technology of China》 2005年第3期268-271,共4页
As electronic packages become more compact, run at faster speeds and dissipate more heat, package designers need more effective thermal management materials. CVD diamond, because of its high thermal conductivity, low ... As electronic packages become more compact, run at faster speeds and dissipate more heat, package designers need more effective thermal management materials. CVD diamond, because of its high thermal conductivity, low dielectric loss and its great mechanical strength, is an excellent material for three dimensional (319) multichip modules (MCMs) in the next generation compact high speed computers and high power microwave components. In this paper, we have synthesized a large area freestanding diamond films and substrates, and polished diamond substrates, which make MCMs diamond film sink becomes a reality. 展开更多
关键词 diamond film substrate SINK 3d multichip modules
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On global dimension of Yetter-Drinfel’d Hopf algebras 被引量:1
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作者 WANG YanHua Department of Applied Mathematics, Shanghai University of Finance and Economics, Shanghai 200433, China 《Science China Mathematics》 SCIE 2009年第10期2154-2162,共9页
In this paper, it is proved that the global dimension of a Yetter-Drinfel’d Hopf algebra coincides with the projective dimension of its trivial module k.
关键词 Hopf algebras Yetter-drinfel’d modules Yetter-drinfel’d Hopf algebras projective dimension global dimension 16W30 16E10
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Non-3d metal modulated zinc imidazolate frameworks for CO_(2) cycloaddition in simulated flue gas under ambient condition
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作者 Yan-Tong Xu Zi-Ming Ye +4 位作者 De-Xuan Liu Xiao-Yun Tian Dong-Dong Zhou Chun-Ting He Xiao-Ming Chen 《Chinese Chemical Letters》 SCIE CAS CSCD 2023年第7期390-393,共4页
Cycloaddition of CO_(2) and epoxide into cyclic carbonate is one of the most efficient ways for CO_(2) conversion with 100% atom-utilization. Metal–organic frameworks are a kind of potential heterogeneous catalysts, ... Cycloaddition of CO_(2) and epoxide into cyclic carbonate is one of the most efficient ways for CO_(2) conversion with 100% atom-utilization. Metal–organic frameworks are a kind of potential heterogeneous catalysts, however, high temperature, high pressure, and high-purity CO_(2) are still required for the reaction.Here, we report two new Zn(Ⅱ) imidazolate frameworks incoporating MoO_(4)^(2–)or WO_(4)^(2–)units, which can catalyse cycloaddition of CO_(2) and epichlorohydrin at room temperature and atomospheric pressure, giving 95% yield after 24 h in pure CO_(2) and 98% yield after 48 h in simulated flue gas(15% CO_(2)+ 85% N_(2)),respectively. For comparison, the analogic Zn(Ⅱ) imidazolate framework MAF-6 without non-3d metal oxide units showed 71% and 33% yields under the same conditions, respectively. The insightful modulation mechanisms of the MoO_(4)^(2–)unit in optimizing the electronic structure of Zn(Ⅱ) centre, facilitating the rate-determined ring opening process, and minimizing the reaction activation energy, were revealed by X-ray photoelectron spectroscopy, temperature programmed desorption and computational calculations. 展开更多
关键词 Non-3d metal modulation Metal-organic framework CO_(2)fixation Flue gas Cycloaddition reaction
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