Thyristor Controlled Phase Shifter:A Comprehensive Survey

Thyristor control phase shifter (TCPS) is one of the new facilities implemented in power network, leading to the development of economically efficient and technically reliable system. This paper introduces the function of TCPS in power system, describes its working principle and structure, and suggests some simple models used in its study and briefly presents the comparison between different types of TCPSs and their applications.

固—液相转移催化羧甲基化反应——IAA 的合成

IAA 是一种高效的植物生长调节剂。采用固—液相转移催化法,由吲哚与氯乙酰聚乙醇酸(CPGA),在相转移催化剂聚乙二醇和固体 KOH 的存在下,于240℃回流5小时,常压下反应制得。相转移催化剂以 PEG 1500为好,PEG/KOH(wt.%)为20,吲哚:(?)CH双_2CO_2(?):KOH 为1:2.3～2.5:4.0～4.2,产率可达87.5%～88.5%。

Regulating the crystal phase of bismuth-based semiconductors for promoted photocatalytic performance

Numerous bismuth-based semiconductors(BBSs)with sophisticated and desirable structures used as photocatalysts for efficient photocatalytic degradation of water organic contaminants have attracted considerable attention.However,regulating the crystal phases and phase transition of BBSs for promoted photocatalytic performance is ignored.Herein,the unique crystal structure and band structure features of each typical BBSs,and the vital roles on phase controlling of each phase were systematically presented based on the classification of BBSs.Notably,the critical factors for the phase transition of BBSs and intrinsic driving forces endowed by phases of BBSs for enhanced photocatalytic performance of organic contaminants removal were also elucidated.This review will provide systematical guidelines and horizons for regulating the crystal phase and phase transition of BBSs,promoting photocatalytic degradation and mineralization of organic contaminants.

Constitutive model for epoxy shape memory polymer with regulable phase transition temperature

The epoxy shape memory polymer(SMP)with adjustable phase transition temperature is a kind of high-performance shape mem-ory polymer,which can change its phase transition temperature and improve its mechanical properties through the process of photo curing.An epoxy SMP constitutive model combining phase transition and viscoelasticity is established by discretizing the epoxy SMP into several glass phase units and rubbery phase units in this paper.The model includes the viscoelastic constitutive equa-tions of glass phase units and rubber phase units,the parameter expression during shape memory process,and material parameter equation during photocuring process.And the stress relaxation behavior of epoxy SMP at different temperatures and the change of material parameters during the photo-curing process are simu-lated numerically,and the simulation results perform consistency with the experimental data.The model can not only relate shape memory effect and phase transformation in physics but also better characterize the viscoelastic properties of SMP and predict the shape memory response of SMP.

Phase regulated suppression and enhancement switches of four-wave mixing and fluorescence

We experimentally study the phase regulated switch between elcctromagnctically induced trans- parency and electromagmetically induced absorption in probe transmission signal and the conver- sion between enhancement and suppression in four-wave mixing and fluorescence signals for the first time. By changing the relative phase, electromagnetically induced transparency can be eonverted into electromagnetically induced absorption. In this process, the conversion from suppression to enhancement is also obtained in four-wave mixing and fluorescence signals. This research can be applied in non-linear optical device like optical switch and optical wavelength convertor.

Phase transition regulation and caloric effect

Solid state refrigeration based on caloric effect is regarded as a potential candidate for replacing vapor-compression refrigeration.Numerous methods have been proposed to optimize the refrigeration properties of caloric materials,of which single field tuning as a relatively simple way has been systemically studied.However,single field tuning with few tunable parameters usually obtains an excellent performance in one specific aspect at the cost of worsening the performance in other aspects,like attaining a large caloric effect with narrowing the transition temperature range and introducing hysteresis.Because of the shortcomings of the caloric effect driven by a single field,multifield tuning on multicaloric materials that have a coupling between different ferro-orders came into view.This review mainly focuses on recent studies that apply this method to improve the cooling performance of materials,consisting of enlarging caloric effects,reducing hysteresis losses,adjusting transition temperatures,and widening transition temperature spans,which indicate that further progress can be made in the application of this method.Furthermore,research on the sign of lattice and spin contributions to the magnetocaloric effect found new phonon evolution mechanisms,calling for more attention on multicaloric effects.Other progress including improving cyclability of FeRh alloys by introducing second phases and realizing a large reversible barocaloric effect by hybridizing carbon chains and inorganic groups is described in brief.

The correlation between serum uric acid level and early- phase insulin secretion in subjects with normal glucose regulation

Objective To investigate the correlation between serum uric acid(SUA)level and early-phase insulin secretion in subjects with normal glucose regulation(NGR).Methods Totally 367 community NGR residents confirmed by a 75g oral glucose tolerance test were enrolled.

Impact of FACTS devices on exercising market power in deregulated electricity market

In power system studies, congestion in trans- mission lines and utilization of flexible alternating current transmission system （FACTS） devices are closely associated. These devices are very important due to their role in power delivery system enhancement. It is to be noted that the generation companies can exercise their market power which depends on the line flows, line constraints, generators＇ location and its share to the individual loads. This issue cannot be overlooked as it creates monopoliness which is against the deregulated market policy. The objective of this paper is to study the impact of market power when FACTS devices like thyristor controlled switching capacitor （TCSC） and thyristor controlled phase angle regulator （TCPAR） are used under steady state operation. The market power is determined using nodal must-run share （NMRS） index for the standard IEEE 14- bus system with and without the above FACTS devices and the results obtained are compared. All the above simula- tions are conducted in a MATLAB 7.9-R2009b environment.