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Hohhot, China

Inner Mongolia University of Science and Technology is a university in Inner Mongolia, China under the authority of the Inner Mongolia government and the education department of Chinese Education. Wikipedia.

Hao X.,Tongji University | Hao X.,Inner Mongolia University of Science and Technology | Zhai J.,Tongji University | Kong L.B.,Nanyang Technological University | Xu Z.,City University of Hong Kong
Progress in Materials Science

Lead zirconate (PbZrO3 or PZ)-based antiferroelectric (AFE) materials, as a group of important electronic materials, have attracted increasing attention for their potential applications in high energy storage capacitors, micro-actuators, pyroelectric security sensors, cooling devices, and pulsed power generators and so on, because of their novel external electric field-induced phase switching behavior between AFE state and ferroelectric (FE) state. The performances of AFE materials are strongly dependent on the phase transformation process, which are mainly determined by the constitutions and the external field. For AFE thin/thick films, the electrical properties are also strongly dependent on their thickness, crystal orientation and the characteristics of electrode materials. Accordingly, various strategies have been employed to tailor the phase transformation behavior of AFE materials in order to improve their performances. Due to their relatively poor electrical strength (low breakdown fields), most PZ-based orthorhombic AFE ceramics are broken down before a critical switching field can be applied. As a consequence, the electric-field-induced transition between AFE and FE phase of only those AFE bulk ceramics, with compositions within tetragonal region near the AFE/FE morphotropic phase boundary (MPB), can be realized experimentally at room temperature. AFE materials with such compositions include (Pb,A)ZrO3 (A = Ba, Sr), (Pb1-3/2xLa x)(Zr1-yTiy)O 3 (PLZT x/(1-y)/y), (Pb0.97La0.02)(Zr,Sn,Ti) O3 (PLZST) and Pb0.99(Zr,Sn,Ti)0.98Nb 0.02O3 (PNZST). As compared to bulk ceramics, AFE thin and thick films always display better electric-field endurance ability. Consequently, room temperature electric-field-induced AFE-FE phase transition could be observed in the AFE thin/thick films with orthorhombic structures. Moreover, AFE films are more easily integrated with silicon technologies. Therefore, AFE thin/thick films have been a subject of numerous researches. This review serves to summarize the recent progress of PZ-based AFE materials, focusing on the external field (electric field, hydrostatic pressure and temperature) dependences of the AFE-FE phase transition, with a specific attention to the performances of AFE films for various potential applications, such as high energy storage, electric field induced strains, pyroelectric effect and electrocaloric effect. © 2014 Elsevier Ltd. All rights reserved. Source

Hao X.,Inner Mongolia University of Science and Technology | Zhai J.,Tongji University
Applied Physics Letters

In this letter, orthorhombic Pb(Nb,Zr,Sn,Ti)O3 (PNZST) and tetragonal (Pb,La)(Zr,Sn,Ti)O3 (PLZST) antiferroelectric (AFE) thin films were deposited on LaNiO3/Pt(111)/TiO2/SiO 2/Si(100) substrates via a sol-gel method. The electrocaloric effect (ECE) of PNZST and PLZST films originated from phase transition between AFE and ferroelectric were studied, based on their pyroelectric results. A large tunable ECE near room temperature was realized in these films under the function of electric field. As the applied electric field increased, the temperature corresponding to the peak of ECE was decreased for the orthorhombic PNZST films, while the temperature was increased for the tetragonal PLZST films. The maximum ECE of 0.040 K · cm/kV in PNZST films and 0.048 K · cm/kV in PLZST films was received at 323 and 305 K, respectively. The results indicated that AFE thin films had the potential for application in tunable cooling devices near room temperature. © 2014 AIP Publishing LLC. Source

Guo J.,CAS Institute of Botany | Guo J.,Inner Mongolia University of Science and Technology | Xu W.,CAS Institute of Botany | Ma M.,CAS Institute of Botany
Journal of Hazardous Materials

Transgenic Arabidopsis thaliana were developed to increase tolerance for and accumulation of heavy metals and metalloids by simultaneous overexpression of AsPCS1 and YCF1 (derived from garlic and baker's yeast) based on the fact that chelation of metals and vacuolar compartmentalization are the main strategies for heavy metals/metalloids detoxification and tolerance in plants. Dual-gene transgenic lines had the longest roots and the highest accumulation of Cd and As than single-gene transgenic lines and wildtype. When grown on cadmium or arsenic (arsenite/arsenate), Dual-gene transgenic lines accumulated over 2-10 folds cadmium/arsenite and 2-3 folds arsenate than wild type or plants expressing AsPCS1 or YCF1 alone. Such stacking modified genes involved in chelation of toxic metals and vacuolar compartmentalization represents a highly promising new tool for use in phytoremediation efforts. © 2011 Elsevier B.V. Source

Zhang Y.,Inner Mongolia University of Science and Technology
Mathematical and Computer Modelling

This paper studies the modelling and identification problems for multi-input single-output (MISO) systems with colored noises. In order to obtain the unbiased recursive estimates of the systems, this paper presents a recursive least squares (RLS) identification algorithm based on bias compensation technique. The basic idea is to eliminate the estimation bias by adding a correction term in the least squares (LS) estimates, a set of stable digital prefilters are suitably designed to preprocess the input sampled data from multi-input channels for the purpose of getting the bias term arisen by colored noises in LS estimates, and further to derive a bias compensation based RLS algorithm. The performance of the developed method is both analyzed theoretically and shown by means of simulation results. © 2011. Source

Chu K.-H.W.,Inner Mongolia University of Science and Technology
Physica B: Condensed Matter

We investigate electric-field-driven transport of electrons in metallic as well as amorphous high-temperature superconductors by using the verified transition-rate approach which has been successfully adopted to study the critical transport of glassy solid helium in very low temperature environment. The critical temperatures related to the nearly frictionless transport of electrons were found to be directly relevant to the (onset) phase-transition temperature of high-temperature superconductors (like MgB 2 and Hg1-xPbxBa2Ca2Cu3O8δ [Hg(x Pb) 1:2:2:3]) after selecting specific activation energies and activation volumes. © 2010 Elsevier B.V. All rights reserved. Source

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