Inter- and Intramolecular Palladium-Catalyzed Allyl Cross-Coupling Reactions Using Allylindium Generated In Situ from Allyl Acetates, Indium, and Indium Trichloride

Seomoon, Dong,Lee, Kooyeon,Kim, Hyunseok,Lee, Phil ,Ho Wiley - VCH Verlag GmbH & Co. KGaA 2007 Chemistry Vol.13 No.18

<P>Inter- and intramolecular palladium-catalyzed allyl cross-coupling reactions using allylindium generated in situ by treatment of allyl acetates with indium and indium trichloride in the presence of Pd<SUP>0</SUP> catalyst and nBuNMe<SUB>2</SUB> in DMF were successfully demonstrated. Allylindium species generated in situ by reductive transmetalation of π-allylpalladium(II) complexes, obtained from a variety of allyl acetates in the presence of Pd<SUP>0</SUP> catalyst together with indium and indium trichloride, were found to be capable of acting as effective nucleophilic coupling partners in Pd-catalyzed cross-coupling reactions. A variety of allyl acetates such as but-1-en-3-yl acetate, crotyl acetate, and 2-methylallyl acetate afforded the corresponding allylic compounds in good yields in cross-coupling reactions. Various electrophilic cross-coupling partners such as aryl iodides and vinyl bromides and triflates participate in these reactions. Not only intermolecular but also intramolecular Pd-catalyzed cross-coupling reactions work equally well to produce the desired allylic coupling products in good yields.</P> <B>Graphic Abstract</B> <P>Inter- and intramolecular cross-coupling reactions work equally well: Allylindium species generated in situ by reductive transmetalation of π-allylpalladium(II) complexes, obtained from a variety of allyl acetates in the presence of a Pd<SUP>0</SUP> catalyst together with indium and indium trichloride, were found to be capable of acting as effective nucleophilic coupling partners in intermolecular and intramolecular Pd-catalyzed cross-coupling reactions. <img src='wiley_img/09476539-2007-13-18-CHEM200601338-content.gif' alt='wiley_img/09476539-2007-13-18-CHEM200601338-content'> </P>

Influence of End-Effect and Cross-Coupling on Torque-Speed Characteristics of Switched Flux Permanent Magnet Machines

Z.Q. Zhu,Z. Azar 전력전자학회 2011 ICPE(ISPE)논문집 Vol.2011 No.5

Switched flux permanent magnet (SFPM) machines have the synergy of PM machines, including high torque density and high efficiency, and switched reluctance (SR) machines, such as simple and robust rotor structure. Therefore, they are potentially attractive for many applications, ranging from traction to aerospace. Comparing with conventional SFPM machines, multi-tooth SFPM machines have additional advantages of using less magnet material but higher torque capability. This paper investigates the influence of the end-effect and crosscoupling on the torque/power-speed characteristics of a multi-tooth (6-4 stator pole/tooth, 19-rotor pole) SFPM machine. Various models at different cross-coupling levels are considered, viz. full cross-coupling on both PM flux linkage and dq-axis inductances, partial cross-coupling on the PM flux linkage only and without cross-coupling. It is found that the partial cross-coupling model, which is much easier and faster, exhibits almost the same accuracy as the full cross-coupling model. Furthermore, the end-effect causes a large reduction in torque-speed characteristics. However, such reduction is more significant in the flux weakening operation region, as confirmed by the 3D finite element (FE) and experimental results.

Derivation of Transfer Function for the Cross-Coupled Filter Systems Using Chain Matrices

Kee-Hong Um 한국인터넷방송통신학회 2018 Journal of Advanced Smart Convergence Vol.7 No.1

In this paper, we derive a transfer function of cross-coupled microwave filter systems by using a characteristics of chain matrices. Depending on the lumped element of capacitor or inductor, the cross-coupled system is negatively- or positively system. We used a ladder network as a starting system composed of several subsystems connected in chain. Each subsystem is descrived by Laplace impedance. By solving the transmission zero characteristic equation derived from the cascaded subsystems, we can find the zeros of filter system with externally cross-coupled lumped elements. With the cross-coupled elements of capacitors, the numerator polynomial of system transfer function is used to locate the quadruplet zeros in complex plane. We show the polynomoials of numerator and denominator of cascaded transfer function, obtaining the zeros of the cross-coupled system.

Cross-Shaped Magnetic Coupling Structure for Electric Vehicle IPT Charging Systems

Siyuan Ren,Chenyang Xia,Limin Liu,Xiaojie Wu,Qiang Yu 전력전자학회 2018 JOURNAL OF POWER ELECTRONICS Vol.18 No.4

Inductive power transfer (IPT) technology allows for charging of electric vehicles with security, convenience and efficiency. However, the IPT system performance is mainly affected by the magnetic coupling structure which is largely determined by the coupling coefficient. In order to get this applied to electric vehicle charging systems, the power pads should be able to transmit stronger power and be able to better sustain various forms of deviations in terms of vertical, horizontal direction and center rotation. Thus, a novel cross-shaped magnetic coupling structure for IPT charging systems is proposed. Then an optimal cross-shaped magnetic coupling structure by 3-D finite-element analysis software is obtained. At marking locations with average parking capacity and no electronic device support, a prototype of a 720*720mm cross-shaped pad is made to transmit 5kW power at a 200mm air gap, providing a 1.54m2 full-power free charging zone. Finally, the leakage magnetic flux density is measured. It indicates that the proposed cross-shaped pad can meet the requirements of the International Commission on Non-Ionizing Radiation Protection (ICNIRP) according to the Australian Radiation Protection and Nuclear Safety Agency (ARPANSA).

교차 결합 현상을 고려한 매입형 영구자석 전동기의 인덕턴스 특성 해석

李相燁(Sang-Yub Lee),郭尙燁(Sang-Yeop Kwak),金在光(Jae-Kwang Kim),鄭炫敎(Hyun-Kyo Jung) 대한전기학회 2006 전기학회논문지 B Vol.55 No.4

In this paper, the inductance characteristics of interior permanent magnet synchronous motor (IPMSM) considering cross-coupling effect is analyzed. It is known that the IPMSM has it's operating point at the saturated region. So the cross-coupling effect exists, therefore cross-coupling inductance exists. With the application of Fixed Permeability Method (FPM), we can obtain more exact inductance characteristics of IPMSM. In this paper, a novel method based on the FPM is proposed, which can consider the cross-coupling effect. And the cross-coupling inductance which is the analysis result is shown. Finally, the validity of proposed method is verified by the comparison with the experimental result.

Cross-Shaped Magnetic Coupling Structure for Electric Vehicle IPT Charging Systems

Ren, Siyuan,Xia, Chenyang,Liu, Limin,Wu, Xiaojie,Yu, Qiang The Korean Institute of Power Electronics 2018 JOURNAL OF POWER ELECTRONICS Vol.18 No.4

Inductive power transfer (IPT) technology allows for charging of electric vehicles with security, convenience and efficiency. However, the IPT system performance is mainly affected by the magnetic coupling structure which is largely determined by the coupling coefficient. In order to get this applied to electric vehicle charging systems, the power pads should be able to transmit stronger power and be able to better sustain various forms of deviations in terms of vertical, horizontal direction and center rotation. Thus, a novel cross-shaped magnetic coupling structure for IPT charging systems is proposed. Then an optimal cross-shaped magnetic coupling structure by 3-D finite-element analysis software is obtained. At marking locations with average parking capacity and no electronic device support, a prototype of a 720*720mm cross-shaped pad is made to transmit 5kW power at a 200mm air gap, providing a $1.54m^2$ full-power free charging zone. Finally, the leakage magnetic flux density is measured. It indicates that the proposed cross-shaped pad can meet the requirements of the International Commission on Non-Ionizing Radiation Protection (ICNIRP) according to the Australian Radiation Protection and Nuclear Safety Agency (ARPANSA).

A comparative experimental study on the cross-plane thermal conductivities of nano-constructed Sb2Te3/(Cu, Ag, Au, Pt) thermoelectric multilayer thin films

Yang Gang,Pan Jiahui,Fu Xuecheng,Hu Zhiyu,Wang Ying,Wu Zhimao,Mu Erzhen,Yan Xue-Jun,Lu Ming-Hui 나노기술연구협의회 2018 Nano Convergence Vol.5 No.22

Thermoelectric multilayer thin films used in nanoscale energy conversion have been receiving increasing attention in both academic research and industrial applications. Thermal transport across multilayer interface plays a key role in improving thermoelectric conversion efficiency. In this study, the cross-plane thermal conductivities of nano-constructed Sb2Te3/(Cu, Ag, Au, Pt) thermoelectric multilayer thin films have been measured using time-domain thermoreflectance method. The interface morphology features of multilayer thin film samples were characterized by using scanning and transmission electron microscopes. The effects of interface microstructure on the cross-plane thermal conductivities of the multilayer thin films have been extensively examined and the thermal transfer mechanism has been explored. The results indicated that electron–phonon coupling occurred at the semiconductor/metal interface that strongly affected the cross-plane thermal conductivity. By appropriately optimizing the period thickness of the metal layer, the cross-plane thermal conductivity can be effectively reduced, thereby improving the thermoelectric conversion efficiency. This work presents both experimental and theoretical understanding of the thermal transport properties of Sb2Te3/metal multilayer thin film junctions with important implications for exploring a novel approach to improving the thermoelectric conversion efficiency. Introduction Thermoelectric multilayer thin films used in nanoscale energy conversion have been receiving increasing attention in both academic research and industrial applications. Thermal transport across multilayer interface plays a key role in improving thermoelectric conversion efficiency. In this study, the cross-plane thermal conductivities of nano-constructed Sb2Te3/(Cu, Ag, Au, Pt) thermoelectric multilayer thin films have been measured using time-domain thermoreflectance method. The interface morphology features of multilayer thin film samples were characterized by using scanning and transmission electron microscopes. The effects of interface microstructure on the cross-plane thermal conductivities of the multilayer thin films have been extensively examined and the thermal transfer mechanism has been explored. The results indicated that electron–phonon coupling occurred at the semiconductor/metal interface that strongly affected the cross-plane thermal conductivity. By appropriately optimizing the period thickness of the metal layer, the cross-plane thermal conductivity can be effectively reduced, thereby improving the thermoelectric conversion efficiency. This work presents both experimental and theoretical understanding of the thermal transport properties of Sb2Te3/metal multilayer thin film junctions with important implications for exploring a novel approach to improving the thermoelectric conversion efficiency. Introduction

Derivation of Transfer Function for the Cross-Coupled Filter Systems Using Chain Matrices

Um, Kee-Hong The Institute of Internet 2018 International journal of advanced smart convergenc Vol.7 No.1

In this paper, we derive a transfer function of cross-coupled microwave filter systems by using a characteristics of chain matrices. Depending on the lumped element of capacitor or inductor, the cross-coupled system is negatively- or positively system. We used a ladder network as a starting system composed of several subsystems connected in chain. Each subsystem is descrived by Laplace impedance. By solving the transmission zero characteristic equation derived from the cascaded subsystems, we can find the zeros of filter system with externally cross-coupled lumped elements. With the cross-coupled elements of capacitors, the numerator polynomial of system transfer function is used to locate the quadruplet zeros in complex plane. We show the polynomoials of numerator and denominator of cascaded transfer function, obtaining the zeros of the cross-coupled system.

An Integrated Approach to the Analysis and Design of a Three-Axis Cross-Coupling Control System

Sungchul Jee,Hakchul Lee 한국정밀공학회 2007 International Journal of Precision Engineering and Vol.8 No.2

We propose a controller design analysis for a cross-coupling control system, 'which is essential for achieving high contouring accuracy in multi-axis CNC systems. The proposed analysis combines three axial controllers for each individual feed drive system together with a cross-coupling controller at the beginning of the design stage in an integrated manner. These two types of controllers used to be separately designed and analyzed since they have different control objectives. The proposed scheme is based on a mathematical formulation of a three-dimensional contour error model and includes a stability analysis for the overall control system and a performance analysis in terms of contouring and tracking accuracy at steady state. A computer simulation was used to demonstrate the validity of the proposed methodology. The performance variation was investigated under different operating conditions and controller gains, and a design range was elicited that met the given performance specifications. The results provide basic guidelines in systematic and comprehensive controller designs for multi-axis CNC systems. A cross-coupling control system was also implemented on a PC-based three-axis CNC testbed and the experimental results confirmed the usefulness of the proposed control system in terms of contouring accuracy.

Cross-coupled Transistor Load Structure in Differential Pairs

Wenqin Xu,Qiang Li,Jing Wang,Yufeng Sun,Yasuaki Inoue 대한전자공학회 2015 ITC-CSCC :International Technical Conference on Ci Vol.2015 No.6

The cross-coupled transistor structure has been widely utilized in LSI circuits. This paper presents a cross-coupled transistor load structure for differential amplifiers and the performance of the structure is analyzed. The differential amplifier composed of the cross-coupled transistor load structure and the differential pair is verified by circuit simulation and the simulation results indicate that the structure can improve the performances of the differential amplifier in several parameters including the gain and the quiescent current.