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植物生长调节剂 4

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

Shanmugam PRABHAKAR KARTHIKEYAN, I. JACOB RAGLEND, D. P. KOTHARI

《能源前沿（英文）》 2013年 第7卷 第4期   页码 448-455 doi: 10.1007/s11708-013-0262-x

摘要： In power system studies, congestion in transmission 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 simulations are conducted in a MATLAB 7.9-R2009b environment.

关键词： flexible alternating current transmission system (FACTS)     thyristor controlled switching capacitor (TCSC)     thyristor controlled phase angle regulator (TCPAR)     market power     must-run generation (MRG)     nodal must-run share (NMRS)    

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Synthesis and characterization of biocompatible polyurethanes for controlled release of hydrophobic and

Juichen YANG,Hong CHEN,Yuan YUAN,Debanjan SARKAR,Jie ZHENG

《化学科学与工程前沿（英文）》 2014年 第8卷 第4期   页码 498-510 doi: 10.1007/s11705-014-1451-9

摘要： Design of biocompatible and biodegradable polymer systems for sustained and controlled release of bioactive agents is critical for numerous biomedical applications. Here, we designed, synthesized, and characterized four polyurethane carrier systems for controlled release of model drugs. These polyurethanes are biocompatible and biodegradable because they consist of biocompatible poly(ethylene glycol) or poly(caprolactone diol) as soft segment, linear aliphatic hexamethylene diisocyanate or symmetrical aliphatic cyclic dicyclohexylmethane-4,4′-diisocyanate as hard segment, and biodegradable urethane linkage. They were characterized with Fourier transform infrared spectroscopy, atomic force microscope, and differential scanning calorimetry, whereas their degradation behaviors were investigated in both phosphate buffered saline and enzymatic solutions. By tuning polyurethane segments, different release profiles of hydrophobic and hydrophilic drugs were obtained in the absence and presence of enzymes. Such difference in release profiles was attributed to a complex interplay among structure, hydrophobicity, and degradability of polyurethanes, the size and hydrophobicity of drugs, and drug-polymer interactions. Different drug-polyurethane combinations modulated the distribution and location of the drugs in polymer matrix, thus inducing different drug release mechanisms. Our results highlight an important role of segmental structure of the polyurethane as an engineering tool to control drug release.

关键词： phase structure     degradation     polyurethanes     controlled release     drug delivery    

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Demand response based congestion management in a mix of pool and bilateral electricity market model

Ashwani KUMAR, Charan SEKHAR

《能源前沿（英文）》 2012年 第6卷 第2期   页码 164-178 doi: 10.1007/s11708-012-0187-9

摘要： The independent system operator (ISO) is a key element in the deregulated structure with one of the responsibilities of transmission congestion management (CM). The ISO opts market based solutions to manage congestion receiving bids from generation companies (GENCOs) as well as distribution companies (DISCOMs) to reschedule their generation and relocate demand. The nodal prices increases during the congestion hours and the demand response to nodal prices will be an effective tool for the control of congestion. In this paper, demand response-based CM has been proposed for a mix of pool and bilateral electricity market model. The linear bid curves have been considered for demand bids to respond to the congestion in the network. The bilateral demand has been obtained with minimum deviations in their preferred schedule. The impact of flexible alternating current transmission system (FACTS) devices viz static var compensator (SVC) and thyristor controlled series compensator (TCSC) has also been considered for demand management during congestion. Multi-line congestion cases have been considered to study the impact on demand response without and with FACTS devices. The proposed approach has been tested on the IEEE 24 bus test system.

关键词： bid function     congestion management (CM)     demand response     pool+bilateral electricity market     static var compensator (SVC)     thyristor controlled series compensator (TCSC)    

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Lamellar thickness transition of melt-crystallized polybuten-1 tetragonal phase: configurational change

Motoi YAMASHITA

《化学科学与工程前沿（英文）》 2009年 第3卷 第1期   页码 26-32 doi: 10.1007/s11705-009-0002-2

摘要： Lamellar crystal thickness of isotactic polybutene-1 ( -PB1) have been investigated for crystallization in the melt over a wide range of crystallization temperature from 40°C to 90°C by small angle X-ray scattering experiments and density measurements. The crystal thickness demonstrates two linear dependences on inverse supercooling and a transition from one dependence to the other has been observed around = 65°C. Each of the two dependences obeys the nucleation theory in the high and low supercooling ranges, respectively. Chain folding free energy determined from the low supercooling range is larger than that determined from the high supercooling range. Possible mechanisms for the transition are discussed taking account of entropy of chain folding directions.

关键词： isotactic polybutene-1     tetragonal phase     crystal thickness     melt growth     chain folding     small angle X-ray scattering     nucleation theory     end surface free energy    

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An interval type-2 fuzzy logic controller for TCSC to improve the damping of power system oscillations

Manoj Kumar PANDA, Gopinath PILLAI, Vijay KUMAR

《能源前沿（英文）》 2013年 第7卷 第3期   页码 307-316 doi: 10.1007/s11708-013-0269-3

摘要： In this paper an interval type-2 fuzzy logic controller (IT2FLC) was proposed for thyristor controlled series capacitor (TCSC) to improve power system damping. For controller design, memberships of system variables were represented using interval type-2 fuzzy sets. The three-dimensional membership function of type-2 fuzzy sets provided additional degree of freedom that made it possible to directly model and handle uncertainties. Simulations conducted on a single machine infinite bus (SMIB) power system showed that the proposed controller was more effective than particle swarm optimization (PSO) tuned and type-1 fuzzy logic (T1FL) based damping controllers. Robust performance of the proposed controller was also validated at different operating conditions, various disturbances and parameter variation of the transmission line parameters.

关键词： power system oscillations     thyristor controlled series capacitor (TCSC)     type-2 fuzzy logic system     interval type-2 fuzzy logic controller (IT2FLC)    

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植物生长调节剂TA乳粉对海带产量和品质的影响

刘德盛,张群

《中国工程科学》 2000年 第2卷 第2期   页码 68-73

摘要：

目前我国海带养殖面积约1.5万hm2，年产干品27t，占世界海藻总产量的50%。三十烷醇（TA）乳粉可显著提高海带的产量和品质，海带苗经2mg/L TA浸泡2h后放养，能促进假根生长，提高保苗率，增加叶绿素、岩藻黄素含量，促进碳、氮代谢，增加干物质积累。处理比对照平均增收干品6.57t/hm2,增产率为35%。同时，海带可比对照增收碘24.24kg/hm2、褐藻胶1.665t/hm2、甘露醇1.278t/hm2。TA乳粉属国内外首创，具有无毒、高效、成本低、不变质及贮运方便等优点，已在全国海带上推广1.6万hm2,创经济效益3亿多元。

关键词： 三十烷醇     海带     植物生长调节剂    

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Fibroblast growth factor 21: a novel metabolic regulator from pharmacology to physiology

null

《医学前沿（英文）》 2013年 第7卷 第1期   页码 25-30 doi: 10.1007/s11684-013-0244-8

摘要：

Fibroblast growth factor 21 (FGF21) is a member of the fibroblast growth factor family. It actually functions as endocrine hormones but does not regulate cell growth and differentiation. It is demonstrated that FGF21 acts on multiple tissue to coordinate carbohydrate and lipid metabolism, including enhancing insulin sensitivity, decreasing triglyceride concentrations, causing weight loss, ameliorating obesity-associated hyperglycemia and hyperlipidemia. Moreover, FGF21 also plays important roles in some physiological processes, such as fasting and feeding, growth hormone axis and thermogenic function of brown adipose tissue. Clinical relevance of FGF21 in humans is still unclear, and the basis and consequences of increased FGF21 in metabolic disease remain to be determined. Both the pharmacological actions and physiological roles make FGF21 attractive drug candidates for treating metabolic disease, but some questions remain to be answered. This article concentrates on recent advances in our understanding of FGF21.

关键词： FGF21     metabolism     pharmacology     physiology     clinical relevance    

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Two-dimensional self-assembly of melem and melemium cations at pH-controlled aqueous solution–Au(111)

Shinobu Uemura,Kenki Sakata,Masashi Aono,Yusuke Nakamura,Masashi Kunitake

《化学科学与工程前沿（英文）》 2016年 第10卷 第2期   页码 294-300 doi: 10.1007/s11705-016-1564-4

摘要： Two-dimensional self-assembly of melem at pH-controlled aqueous solution-Au(111) interfaces has been investigated by electrochemical scanning tunneling microscopy. In the solutions with pH>p of melem, two ordered self-assembled structures (honeycomb and close-packed structures) and one disordered fibrillar structure were observed as a function of the surface coverage of melem controlled by the electrode potential. In contrast, in the acidic solution with pH

关键词： self-assembly     scanning tunneling microscopy     electrochemistry     structural phase transition     melem    

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Precise semi-analytical inverse kinematic solution for 7-DOF offset manipulator with arm angle optimization

《机械工程前沿（英文）》 2021年 第16卷 第3期   页码 435-450 doi: 10.1007/s11465-021-0630-x

摘要： Seven-degree-of-freedom redundant manipulators with link offset have many advantages, including obvious geometric significance and suitability for configu-ration control. Their configuration is similar to that of the experimental module manipulator (EMM) in the Chinese Space Station Remote Manipulator System. However, finding the analytical solution of an EMM on the basis of arm angle parameterization is difficult. This study proposes a high-precision, semi-analytical inverse method for EMMs. Firstly, the analytical inverse kinematic solution is established based on joint angle parameterization. Secondly, the analytical inverse kinematic solution for a non-offset spherical–roll–spherical (SRS) redundant manipulator is derived based on arm angle parameterization. The approximate solution of the EMM is calculated in accordance with the relationship between the joint angles of the EMM and the SRS manipulator. Thirdly, the error is corrected using a numerical method through the analytical inverse solution based on joint angle parameterization. After selecting the stride and termination condition, the precise inverse solution is computed for the EMM based on arm angle parameterization. Lastly, case solutions confirm that this method has high precision, and the arm angle parameterization method is superior to the joint angle parameterization method in terms of parameter selection.

关键词： 7-DOF redundant manipulator     inverse kinematics     semi-analytical     arm angle     link offset    

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Evaluating the material strength from fracture angle under uniaxial loading

Jitang FAN

《结构与土木工程前沿（英文）》 2019年 第13卷 第2期   页码 288-293 doi: 10.1007/s11709-018-0480-8

摘要： The most common experimental methods of measuring material strength are the uniaxial compressive and tensile tests. Generally, shearing fracture model occurs in both the tests. Compressive strength is higher than tensile strength for a material. Shearing fracture angle is smaller than 45° under uniaxial compression and greater than 45° under uniaxial tension. In this work, a unified relation of material strength under uniaxial compression and tension is developed by correlating the shearing fracture angle in theory. This constitutive relation is quantitatively illustrated by a function for analyzing the material strength from shear fracture angle. A computational simulation is conducted to validate this theoretical function. It is full of interest to give a scientific illustration for designing the high-strength materials and engineering structures.

关键词： strength     fracture     mechanics    

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Autoimmune regulator regulates autophagy in THP-1 human monocytes

Liang SHI, Li-Hua HU, Yi-Rong LI

《医学前沿（英文）》 2010年 第4卷 第3期   页码 336-341 doi: 10.1007/s11684-010-0096-4

摘要： The autoimmune regulator (AIRE) is a crucial factor for the induction of central tolerance, and mutations in this gene lead to abnormal immune responses. However, the role of AIRE in autophagy in immune cells, especially in monocytes, is obscure. In the present study, we found that overexpression of AIRE in THP-1 human monocytes resulted in increased endogenous light chain 3 (LC3)-II level and elevated LC3 positive vesicles. Moreover, an autophagy inhibitor or knockdown of AIRE by small interference RNA attenuated these effects. In contrast, the expression of p62/SQSTM1 remained unchanged in THP-1 cells after the corresponding treatment. Our findings indicate that AIRE plays a role in the regulation of autophagy in THP-1 human monocytes.

关键词： autoimmune regulator     autophagy     monocytes     light chain 3 (LC3)    

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A linear quadratic regulator control of a stand-alone PEM fuel cell power plant

Amar BENAISSA, Boualaga RABHI, Ammar MOUSSI, Dahmani AISSA

《能源前沿（英文）》 2014年 第8卷 第1期   页码 62-72 doi: 10.1007/s11708-013-0291-5

摘要： This paper introduces a technique based on linear quadratic regulator (LQR) to control the output voltage at the load point versus load variation from a stand-alone proton exchange membrane (PEM) fuel cell power plant (FCPP) for a group housing use. The controller modifies the optimal gains by minimizing a cost function, and the phase angle of the AC output voltage to control the active and reactive power output from an FCPP to match the terminal load. The control actions are based on feedback signals from the terminal load, output voltage and fuel cell feedback current. The topology chosen for the simulation consists of a 45 kW proton exchange membrane fuel cell (PEMFC), boost type DC/DC converter, a three-phase DC/AC inverter followed by an LC filter. Simulation results show that the proposed control strategy operated at low commutation frequency (2 kHz) offers good performances versus load variations with low total harmonic distortions (THD) , which is very useful for high power applications.

关键词： modeling of proton exchange membrane fuel cell (PEMFC)     controlling of PEMFC     linear quadratic regulator (LQR)     DC/DC converter     DC/AC inverter    

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THE ANTHOCYANIN BIOSYNTHETIC REGULATOR MDMYB1 POSITIVELY REGULATES ASCORBIC ACID BIOSYNTHESIS IN APPLE

《农业科学与工程前沿（英文）》 2021年 第8卷 第2期

摘要：

Ascorbic acid (AsA, vitamin C) is involved in the regulation of many aspects of plant growth and development. It is an essential micronutrient for humans and can prevent scurvy, maintain the health of gums and blood vessels, reduce the level of plasma cholesterol and enhance the immune systen. Apple cultivars Orin and Guanghui were crossed to obtain a group of hybrid offspring with and without red flesh in the course of assessing apple germplasm resources. Unexpectedly, the red-flesh apples had higher AsA contents than other apples. Further studies showed that the anthocyanin biosynthetic regulator MdMYB1 directly activates the expression of dehydroascorbate reductase gene MdDHAR, thus promoting the activity of the DHAR enzyme and the accumulation of AsA. This finding reveals the mechanism leading to high AsA levels in red-flesh apples and suggests a new idea to cultivate red-flesh apples with high AsA contents and produce AsA efficiently and without pollution.

 

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THE ANTHOCYANIN BIOSYNTHETIC REGULATOR MDMYB1 POSITIVELY REGULATES ASCORBIC ACID BIOSYNTHESIS IN APPLE

Jianping AN, Xiaofei WANG, Chunxiang YOU, Yujin HAO

《农业科学与工程前沿（英文）》   页码 231-235 doi: 10.15302/J-FASE-2020367

摘要： Ascorbic acid (AsA, vitamin C) is involved in the regulation of many aspects of plant growth and development. It is an essential micronutrient for humans and can prevent scurvy, maintain the health of gums and blood vessels, reduce the level of plasma cholesterol and enhance the immune systen. Apple cultivars Orin and Guanghui were crossed to obtain a group of hybrid offspring with and without red flesh in the course of assessing apple germplasm resources. Unexpectedly, the red-flesh apples had higher AsA contents than other apples. Further studies showed that the anthocyanin biosynthetic regulator MdMYB1 directly activates the expression of dehydroascorbate reductase gene , thus promoting the activity of the DHAR enzyme and the accumulation of AsA. This finding reveals the mechanism leading to high AsA levels in red-flesh apples and suggests a new idea to cultivate red-flesh apples with high AsA contents and produce AsA efficiently and without pollution.

关键词： anthocyanin     apples     ascorbic acid     MdMYB1     vitamin C    

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Controlled synthesis of uniform silver nanowires with high aspect ratios in aqueous solutions of gemini

XU Jian, LIU Weijun, LIU Honglai, HU Ying

《化学科学与工程前沿（英文）》 2007年 第1卷 第3期   页码 221-227 doi: 10.1007/s11705-007-0040-6

摘要： A simple solution-phase approach has been demonstrated for the large-scale synthesis of silver nanowires with diameters in the range of 15 25 nm, and lengths usually in the range of tens of micrometers. In the presence of gemini surfactant 1,3-bis(cetyldimethylammonium) propane dibromide (16-3-16), the growth of silver could be directed into a highly anisotropic mode to form uniform nanowires with aspect ratios up to about 2,000. X-ray photoelectron spectroscopy (XPS), transmission electron microscopy (TEM), energy-dispersive X-ray (EDX), X-ray powder diffraction (XRD), electron diffraction (ED), and UV-vis absorption spectroscopy, were used to characterize the as-prepared silver nanowires, indicating the formation of a highly pure phase, good crystallinity, as well as a uniform diameter.

关键词： solution-phase     photoelectron spectroscopy     16-3-16     surfactant     transmission    

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标题 作者 时间 类型 操作

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

Shanmugam PRABHAKAR KARTHIKEYAN, I. JACOB RAGLEND, D. P. KOTHARI

期刊论文

Synthesis and characterization of biocompatible polyurethanes for controlled release of hydrophobic and

Juichen YANG,Hong CHEN,Yuan YUAN,Debanjan SARKAR,Jie ZHENG

期刊论文

Demand response based congestion management in a mix of pool and bilateral electricity market model

Ashwani KUMAR, Charan SEKHAR

期刊论文

Lamellar thickness transition of melt-crystallized polybuten-1 tetragonal phase: configurational change

Motoi YAMASHITA

期刊论文

An interval type-2 fuzzy logic controller for TCSC to improve the damping of power system oscillations

Manoj Kumar PANDA, Gopinath PILLAI, Vijay KUMAR

期刊论文

植物生长调节剂TA乳粉对海带产量和品质的影响

刘德盛,张群

期刊论文

Fibroblast growth factor 21: a novel metabolic regulator from pharmacology to physiology

null

期刊论文

Two-dimensional self-assembly of melem and melemium cations at pH-controlled aqueous solution–Au(111)

Shinobu Uemura,Kenki Sakata,Masashi Aono,Yusuke Nakamura,Masashi Kunitake

期刊论文

Precise semi-analytical inverse kinematic solution for 7-DOF offset manipulator with arm angle optimization

期刊论文

Evaluating the material strength from fracture angle under uniaxial loading

Jitang FAN

期刊论文

Autoimmune regulator regulates autophagy in THP-1 human monocytes

Liang SHI, Li-Hua HU, Yi-Rong LI

期刊论文

A linear quadratic regulator control of a stand-alone PEM fuel cell power plant

Amar BENAISSA, Boualaga RABHI, Ammar MOUSSI, Dahmani AISSA

期刊论文

THE ANTHOCYANIN BIOSYNTHETIC REGULATOR MDMYB1 POSITIVELY REGULATES ASCORBIC ACID BIOSYNTHESIS IN APPLE

期刊论文

THE ANTHOCYANIN BIOSYNTHETIC REGULATOR MDMYB1 POSITIVELY REGULATES ASCORBIC ACID BIOSYNTHESIS IN APPLE

Jianping AN, Xiaofei WANG, Chunxiang YOU, Yujin HAO

期刊论文

Controlled synthesis of uniform silver nanowires with high aspect ratios in aqueous solutions of gemini

XU Jian, LIU Weijun, LIU Honglai, HU Ying

期刊论文