Hangzhou, China

Zhejiang Sci-Tech University is a university in Zhejiang province provides programs in the fields of engineering, science, humanities , economics, management and law with engineering being its main focus. It is run jointly by Ministry of Education and the Zhejiang provincial government, the latter being the main administrative body. Wikipedia.

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An absolute distance measurement apparatus and method using laser interferometric wavelength leverage includes a light source system, a wavelength-leverage laser interferometric system and an interference signal processing and controlling system. The light source system outputs a orthogonally linearly polarized beam with the wavelength _(1 )and the wavelength _(2). The orthogonally linearly polarized beam projects onto the wavelength-leverage laser interferometric system to form the interference beam. The interference beam projects onto the interference signal processing and controlling system. In the wavelength-leverage laser interferometric system, the synthetic wavelength and the single wavelength as well as the measured absolute distance and the moving displacement of the cube-corner prism in the reference arm form a wavelength-leverage absolute distance measurement relationship.

Wu X.-F.,Zhejiang Sci-Tech University | Wu X.-F.,Leibniz Institute for Catalysis at the University of Rostock | Neumann H.,Leibniz Institute for Catalysis at the University of Rostock | Beller M.,Leibniz Institute for Catalysis at the University of Rostock
Chemical Reviews | Year: 2013

The major developments of palladium-catalyzed carbonylative syntheses of heterocycles was reviewed. The application of palladium catalyzed carbonylation reactions in the synthesis of four membered lactones was first reported by Cowell and Stille in 1980. They used PdCl2(PPh3) 2 as catalyst, and the lactones were synthesized in high yields under mild conditions. Dupont and co-workers developed a Pd(OAc)2/2- PyPPh2 system for the production of various lactones from alkynols. Palladium catalyzed carbonylation of aziridines represents another convincing procedure for the synthesis of lactams. The methodologies developed by Brickner and Tsuji and their co-workers successfully avoid the use of aziridines in the preparation of lactams, but the specificity of starting materials limited the scope. Six-membered ring lactones were produced preferentially in acetonitrile using cationic palladium complexes coordinated by certain chelating diphosphines (dppb) as catalyst.

Northeast Agricultural University and Zhejiang Sci-Tech University | Date: 2016-01-27

Inclined interpolation wide and narrow row spacing rice seedling transplanting mechanism belongs to agricultural machinery. A left power output shaft and a right power output shaft are correspondingly assembled on the left side part and right side part of the power transmission case, wherein the axes of the left power shaft and the right power output shaft are symmetrically arranged and incline downwards relative to the horizontal plane, and wherein the left transplanting mechanism and the right transplanting mechanism are perpendicularly attached to the left power output shaft and the right power output shaft respectively to form a V-shaped symmetrical structure with constant seedling taking space and narrow rice seedling transplanting space in the whole. A driven bevel gear is attached to the right power output shaft or the left power output shaft. A driving bevel gear on a main driving shaft in the power transmission case meshes with the driven bevel gear. A left bevel gear and a right bevel gear are respectively attached to the left power output shaft and the right power output shaft and the left bevel gear meshes with the right bevel gear mesh, wherein the transmission ratio is 1:1. It is realized in the invention that the left and right transplanting mechanisms both offset inward to plant the seedlings after they fetched the seedlings. It has simple structure and small space occupation, which makes the inward inclined narrow row transplanting possible. It needs low cost and easy installation. The row spacing is increased by 10 cm compared with the transplanted line. Therefore the connect seedling line has less possibility of hilling mud and dammed water and the seedlings avoid being pushed down. The invention is particularly suitable for general riding-type transplanters with high speed operation and integrated floating boards.

Li Q.,Zhejiang Sci-Tech University
IEEE Transactions on Robotics | Year: 2010

Parasitic motion is a major drawback of the general 1T2R parallel mechanism (PM), where T denotes a translation degree of freedom (DOF) and R a rotational DOF. This paper investigates the type synthesis of the 1T2R PM without parasitic motion. First, a brief review on the planar spherical bond and its mechanical generators is presented. Then, the difference between the general and special aT bR motion is discussed. Relations between the parasitic motion and the general and special aTb R motion are revealed. An infinitesimal 1T2R PM with rotation bifurcation is presented as a special case. Further, the definition of the 1T2R PM without parasitic motion is presented, and the limb bond {G(u)}{S(N)} is identified. Geometrical conditions to construct an 1T2R PM without parasitic motion are presented, and nonoverconstrained 1T2R PMs without parasitic motion are synthesized. Idle pairs in the nonoverconstrained 1T2R PMs without parasitic motion are detected. Finally, overconstrained 1T2R PMs without parasitic motion are obtained by removing the idle pairs in the nonoverconstrained 1T2R PMs. © 2010 IEEE.

Wang Y.,Zhejiang Sci-Tech University
Physica Status Solidi - Rapid Research Letters | Year: 2010

Using first-principles calculations, we investigate the electronic properties of two-dimensional hydrogenated and semihydrogenated hexagonal boron nitride (BN) sheets. We find that the hydrogenation effects in BN sheets are quite different from those in the graphene sheets. The hydrogenization changes the band character of BN sheets, which causes the hydrogenated BN sheet having a smaller band gap than the pristine one. While for the semihydrogenated one, the stable B-semihydro BN sheet is a ferromagnetic metal due to the unpaired 2pz electrons of N atoms. Our studies demonstrate that the electronic properties of BN sheets can be well tuned by the hydrogenation. © 2010 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Salvia miltiorrhiza is one of the most important traditional Chinese medicinal plants because of its excellent performance in treating coronary heart disease. Phenolic acids mainly including caffeic acid, rosmarinic acid and salvianolic acid B are a group of active ingredients in S. miltiorrhiza. Abscisic acid (ABA), gibberellin (GA) and ethylene are three important phytohormones. In this study, effects of the three phytohormones and their interactions on phenolic production in S. miltiorrhiza hairy roots were investigated. The results showed that ABA, GA and ethylene were all effective to induce production of phenolic acids and increase activities of PAL and TAT in S. miltiorrhiza hairy roots. Effects of phytohormones were reversed by their biosynthetic inhibitors. Antagonistic actions between the three phytohormones played important roles in the biosynthesis of phenolic acids. GA signaling is necessary for ABA and ethylene-induced phenolic production. Yet, ABA and ethylene signaling is probably not necessary for GA3-induced phenolic production. The complex interactions of phytohormones help us reveal regulation mechanism of secondary metabolism and scale-up production of active ingredients in plants.

Pei D.,Zhejiang Sci-Tech University
International Journal of Approximate Reasoning | Year: 2012

Fuzzy reasoning includes a number of important inference methods for addressing uncertainty. This line of fuzzy reasoning forms a common logical foundation in various fields, such as fuzzy logic control and artificial intelligence. The full implication triple I method (a method only based on implication, TI method for short) for fuzzy reasoning is proposed in 1999 to improve the popular CRI method (a hybrid method based on implication and composition). The current paper delves further into the TI method, and a sound logical foundation is set for the TI method based on the monoidal t-norm based logical system MTL. © 2012 Elsevier Inc. All rights reserved.

Liao Z.,Zhejiang Sci-Tech University
Renewable and Sustainable Energy Reviews | Year: 2016

The rapid growth of China's installed wind power capacity in recent years is closely related to the wind energy policies issued by the Chinese government. Using content analysis and quantitative analysis methods, this paper studies the historical evolution of Chinese wind energy policies. Based on 72 wind energy policies issued in the past two decades (1995-2014), this paper analyzes the issuing organization, form, number and stringency of wind energy policies and compares different policy instruments in two periods. The results show that the number and stringency of wind energy policies fluctuated greatly from 1995 to 2014 and that more than twenty organizations had independently or jointly issued the policies. The main organization issuing wind energy policies, however, is the department that controls key economic and administrative resources and not the one that is in charge of wind energy. Of the 72 policies issued, twenty-three took the form of notices, and eleven were measures. As to the policy instrument, environmental policies are most widely applied by the Chinese government, and "regulation control" and "goal-planning" instruments are the ones most frequently adopted. Furthermore, the application of supply- and demand-type policies is inadequate, and few effective instruments have been adopted. © 2015 Elsevier Ltd. All rights reserved.

A laser heterodyne interferometric straightness measurement apparatus and method with six DOFs determination includes a part for determining the straightness and its position based on laser heterodyne interferometry and a part for error determination and compensation. The optical path for determination of four DOFs errors including three common beam-splitters, a polarizing beam-splitter, a planar mirror, a convex lens, a position-sensitive detector and two quadrant detectors is added in the optical configuration of the part for determining the straightness and its position based on laser heterodyne interferometry.

The present invention discloses a processing method for laser heterodyne interferometric signal based on locking edge with high frequency digital signal. A reference signal and a measurement signal of heterodyne interferometer, after being processed by photodetector, signal amplifier, filtering circuit, voltage comparator and high frequency digital edge locking module, are transferred to pulse counting synchronized latching processing module, to obtain entire cycle interference fringe numbers and filling pulse numbers in one interference fringe cycle, of the reference signal and the measurement signal; the numbers are transferred to a computer to obtain displacement and speed of a measured object; usage of a high frequency digital pulse signal to lock the rising edge of laser heterodyne interferometric signal can improve the gradient of the rising edge of interference signal and eliminate wrong pulse caused by noises, and improve the accuracy and stability of the processing for the following signals.

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