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Precursor engineering enables high-performance all-inorganic CsPbIBr_(2) perovskite solar cells with a record efficiency approaching 13%
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作者 Qingyan Chang Yidan An +8 位作者 Huaiman Cao Yuzhen Pan Liangyu Zhao Yulong Chen Yi We Sai-Wing Tsang Hin-Lap Yip Licheng Sun Ze Yu 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第3期16-22,I0003,共8页
All-inorganic CsPbIBr_(2) perovskite has attracted widespread attention in photovoltaic and other optoelectronic devices because of its superior thermal stability.However,the deposition of high-quality solutionprocess... All-inorganic CsPbIBr_(2) perovskite has attracted widespread attention in photovoltaic and other optoelectronic devices because of its superior thermal stability.However,the deposition of high-quality solutionprocessed CsPbIBr_(2) perovskite films with large thicknesses remains challenging.Here,we develop a triple-component precursor(TCP) by employing lead bromide,lead iodide,and cesium bromide,to replace the most commonly used double-component precursor(DCP) consisting of lead bromide and cesium iodide.Remarkably,the TCP system significantly increases the solution concentration to 1.3 M,leading to a larger film thickness(~390 nm) and enhanced light absorption.The resultant CsPbIBr_(2) films were evaluated in planar n-i-p structured solar cells,which exhibit a considerably higher optimal photocurrent density of 11.50 mA cm^(-2) in comparison to that of DCP-based devices(10.69 mA cm^(-2)).By adopting an organic surface passivator,the maximum device efficiency using TCP is further boosted to a record efficiency of 12.8% for CsPbIBr_(2) perovskite solar cells. 展开更多
关键词 All-inorganic perovskite solar cells CsPbIBr_(2) Precursor engineering Solubility high performance
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Determination of Benzo[a]pyrene in Edible Oil by High Performance Liquid Chromatography-Fluorescence Detector (HPLC-FL)
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作者 Guixia YANG Jie LIU +3 位作者 Xiujuan WANG Fenglan ZHANG Kun XIN Chunli KONG 《Agricultural Biotechnology》 2024年第2期8-9,19,共3页
In this study, an optimized high performance liquid chromatography-fluorescence detector (HPLC-FL) method for the determination of benzo[a]pyrene in edible oil was established. HPLC was performed with Thermo Fisher Sc... In this study, an optimized high performance liquid chromatography-fluorescence detector (HPLC-FL) method for the determination of benzo[a]pyrene in edible oil was established. HPLC was performed with Thermo Fisher Scientific C18 column (250 mm×4.6 mm, 5 μm) as the chromatographic column and acetonitrile and water as the mobile phase, and the excitation wavelength and emission wavelength of fluorescence detector were 286 and 430 nm, respectively. The response was high, and the linear range was 0.5-10.0 ng/ml. The lowest limit of detection was 0.11 ng/ml, and the average recovery was 92.5%. This method is suitable for quantitative analysis of benzo[a]pyrene content in edible oil. 展开更多
关键词 BENZO[A]PYRENE high performance liquid chromatography Fluorescence detector
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A review of high performance computing applications in high-speed rail systems
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作者 Shenyuan Ren Yidong Li 《High-Speed Railway》 2023年第2期92-96,共5页
Further improving the railway innovation capacity and technological strength is the important goal of the 14th Five-Year Plan for railway scientific and technological innovation.It includes promoting the deep integrat... Further improving the railway innovation capacity and technological strength is the important goal of the 14th Five-Year Plan for railway scientific and technological innovation.It includes promoting the deep integration of cutting-edge technologies with the railway systems,strengthening the research and application of intelligent railway technologies,applying green computing technologies and advancing the collaborative sharing of transportation big data.The high-speed rail system tasks need to process huge amounts of data and heavy workload with the requirement of ultra-fast response.Therefore,it is of great necessity to promote computation efficiency by applying High Performance Computing(HPC)to high-speed rail systems.The HPC technique is a great solution for improving the performance,efficiency,and safety of high-speed rail systems.In this review,we introduce and analyze the application research of high performance computing technology in the field of highspeed railways.These HPC applications are cataloged into four broad categories,namely:fault diagnosis,network and communication,management system,and simulations.Moreover,challenges and issues to be addressed are discussed and further directions are suggested. 展开更多
关键词 high performance computing high-speed rail
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Air-Stable,Eco-Friendly RRAMs Based on Lead-Free Cs_(3)Bi_(2)Br_(9)Perovskite Quantum Dots for High-Performance Information Storage
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作者 Xiaofei Cao Zhuangzhuang Ma +4 位作者 Teng Cheng Yadong Wang Zhifeng Shi Jizheng Wang Li Zhang 《Energy & Environmental Materials》 SCIE EI CAS CSCD 2023年第5期406-414,共9页
Development of lead-free halide perovskites that are innocuous and stable has become an attractive trend in resistive random access memory(RRAM)fields.However,their inferior memory properties compared with the lead-ba... Development of lead-free halide perovskites that are innocuous and stable has become an attractive trend in resistive random access memory(RRAM)fields.However,their inferior memory properties compared with the lead-based analogs hinder their commercialization.Herein,the lead-free Cs_(3)Bi_(2)Br_(9)perovskite quantum dot(PQD)-based RRAMs are reported with outstanding memory performance,where Cs_(3)Bi_(2)Br_(9)quantum dots(QDs)are synthesized via a modified ligand-assisted recrystallization process.This is the first report of applying Cs_(3)Bi_(2)Br_(9)QDs as the switching layer for RRAM device.The Cs_(3)Bi_(2)Br_(9)QD device demonstrates nonvolatile resistive switching(RS)effect with large ON/OFF ratio of 105,low set voltage of-0.45 V,as well as good reliability,reproducibility,and flexibility.Concurrently,the device exhibits the notable tolerance toward moisture,heat and light illumination,and long-term stability of 200 days.More impressively,the device shows the reliable light-modulated RS behavior,and therefrom the logic gate operations including"AND"and"OR"are implemented,foreboding its prospect in logic circuits integrated with storage and computation.Such multifunctionality of device could be derived from the unique 2D layered crystal structure,small particle size,quantum confinement effect,and photoresponse of Cs_(3)Bi_(2)Br_(9)QDs.This work provides the strategy toward the high-performance RRAMs based on stable and eco-friendly perovskites for future applications. 展开更多
关键词 air stability high memory performance lead-free perovskite quantum dots light-assisted logic gate operation RRAM devices
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Preface to Special Issue on Towards High Performance Ga_(2)O_(3) Electronics: Epitaxial Growth and Power Devices(Ⅰ)
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作者 Genquan Han Shibing Long +2 位作者 Yuhao Zhang Yibo Wang Zhongming Wei 《Journal of Semiconductors》 EI CAS CSCD 2023年第6期4-6,共3页
There is currently great optimism within the electronics community that gallium oxide(Ga_(2)O_(3)) ultra-wide bandgap semiconductors have unprecedented prospects for eventually revolutionizing a rich variety of power ... There is currently great optimism within the electronics community that gallium oxide(Ga_(2)O_(3)) ultra-wide bandgap semiconductors have unprecedented prospects for eventually revolutionizing a rich variety of power electronic applications. Specially, benefiting from its ultra-high bandgap of around 4.8 eV, it is expected that the emerging Ga_(2)O_(3) technology would offer an exciting platform to deliver massively enhanced device performance for power electronics and even completely new applications. 展开更多
关键词 Epitaxial Growth and Power Devices Preface to Special Issue on Towards high performance Ga_(2)O_(3)Electronics POWER
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Simultaneous Determination of 14 β-Receptor Agonists Residues in Mutton by High Performance Liquid Chromatography-Tandem Mass Spectrometry (HPLC-MS/MS)
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作者 Zhe MENG Jianhua WANG +5 位作者 Bo LIU Yuhang GUO Haoshuang DONG Pingyang SHAN Dawei WANG Yajuan SONG 《Agricultural Biotechnology》 CAS 2023年第5期55-58,共4页
[Objectives]A high performance liquid chromatography-tandem mass spectrometry(HPLC-MS/MS)method was established for the determination of 14β-receptor agonist residues in mutton.[Methods]Samples were hydrolyzed byβ-g... [Objectives]A high performance liquid chromatography-tandem mass spectrometry(HPLC-MS/MS)method was established for the determination of 14β-receptor agonist residues in mutton.[Methods]Samples were hydrolyzed byβ-glucuronidase and extracted with 5%acetic acid-acetonitrile(1:99,V/V)solution.An Eclipse plus C 18 column was used for separation,and the MRM mode was used for qualitative analysis,and the external standard method was used for quantitative analysis of matrix standard solutions.[Results]Under the optimal conditions,the retention time of the 14 kinds ofβ-receptor agonists ranged from 1.0 to 9.5 min.When the mass concentration was in the range of 0.05-0.50μg/ml,the linear relationship ofβ-receptor agonists was good,with correlation coefficients(r)≥0.9992.The detection limits of the method were in the range of 0.04-0.87μg/kg,and the quantitative limits were in the range of 0.35-1.86μg/kg.The average recovery values were in the range of 82.8%-108.9%,with RSDs(n=6)in the range of 1.9%-6.7%.[Conclusions]The method is simple,sensitive,reproducible,accurate,and can be used for simultaneous determination of the 14 kinds ofβ-receptor agonist residues in mutton. 展开更多
关键词 MUTTON high performance liquid chromatography-tandem mass spectrometry β-receptor agonist RESIDUE
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Highly reinforce the interface stability using 2-Phenyl-1H-imidazole-1-sulfonate electrolyte additive to enhance the high temperature performance of LiNi_(0.8)Co_(0.1)Mn_(0.1)O_(2)/graphite batteries
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作者 Xin He Yiting Li +8 位作者 Wenlian Wang Xueyi Zeng Huilin Hu Haijia Li Weizhen Fan Chaojun Fan Jian Cai Zhen Ma Junmin Nan 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2023年第5期10-22,I0001,共14页
This work develops 2-Phenyl-1H-imidazole-1-sulfonate(PHIS)as a multi-functional electrolyte additive for H2O/HF scavenging and film formation to improve the high temperature performance of LiNi_(0.8)Co_(0.1)Mn_(0.1)O_... This work develops 2-Phenyl-1H-imidazole-1-sulfonate(PHIS)as a multi-functional electrolyte additive for H2O/HF scavenging and film formation to improve the high temperature performance of LiNi_(0.8)Co_(0.1)Mn_(0.1)O_(2)/graphite batteries.After 450 cycles at room temperature(25℃),the discharge capacity retentions of batteries with blank and PHIS-containing electrolyte are 56.03%and 94.92%respectively.After 230 cycles at high temperatures(45℃),their values are 75.30%and 88.38%respectively.The enhanced electrochemical performance of the batteries with PHIS-containing electrolyte is supported by the spectroscopic characterization and theoretical calculations.It is demonstrated that this PHIS electrolyte additive can facilitate the construction of the electrode interface films,remove the H2O/HF in the electrolyte,and improve the electrochemical performance of the batteries.This work not only develops a sulfonate-based electrolyte but also can stimulate new ideas of functional additives to improve the battery performance. 展开更多
关键词 LiNi_(0.8)Co_(0.1)Mn_(0.1)O_(2)/graphite battery high temperature performance H_(2)O/HF scavenger 2-Phenyl-1H-imidazole-1-sulfonate Electrolyte additive
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High-Performance of Power System Based upon ANFIS (Adaptive Neuro-Fuzzy Inference System) Controller 被引量:1
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作者 Yousif I. Al-Mashhadany 《Journal of Energy and Power Engineering》 2014年第4期729-734,共6页
The proposed controller incorporates FL (fuzzy logic) algorithm with ANN (artificial neural network). ANFIS replaces the conventional PI controller, tuning the fuzzy inference system with a hybrid learning algorit... The proposed controller incorporates FL (fuzzy logic) algorithm with ANN (artificial neural network). ANFIS replaces the conventional PI controller, tuning the fuzzy inference system with a hybrid learning algorithm. A tuning method is proposed for training of the neuro-fuzzy controller. The best rule base and the best training algorithm chosen produced high performance in the ANFIS controller. Simulation was done on Matlab Ver. 2010a. A case study was chopper-fed DC motor drive, in continuous and discrete modes. Satisfactory results show the ANFIS controller is able to control dynamic highly-nonlinear systems. Tuning it further improved the results. 展开更多
关键词 ANFIS controller power system high performance learning algorithm.
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High Performance Bilinear Differential Preamplifier for BESⅢ Time-of-Flight System
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作者 李玉生 冼泽 安琪 《Plasma Science and Technology》 SCIE EI CAS CSCD 2005年第3期2875-2878,共4页
A time-of-flight (TOF) detector has been used in the BESIII experiment to provide charged particle identification. In this paper, we present a novel high performance differential amplifier, which has been designed for... A time-of-flight (TOF) detector has been used in the BESIII experiment to provide charged particle identification. In this paper, we present a novel high performance differential amplifier, which has been designed for amplifying the signals from the detectors. The preamplifier can amplify differential signals, which can help to eliminate the common mode pickup, and increase the signal-to-noise ratio (SNR). Bilinear gain is one of the features of this preamplifier, which greatly increases the dynamic range and avoids the dead time of the preamplifier. In order to describe the bilinear gain, a 4-parameter function is developed. And this 4-parameter function can also be used in the calibration of the time walk caused by the amplitude due to the bilinear gain. The preamplifier has a gain about 10V/V with a small signal and about 1.0V/V with a large signal. The rise time of the preamp is less than 2 ns. 展开更多
关键词 bilinear gain high performance preamplifier differential signal
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Study on the Flow Injection Micro-Column Pre-Separation System Coupled With High Performance Liquid Chromatography for the Determination of Ecdysterone in Traditional Chinese Medicine
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作者 SHUAI Qin QIN Yong-chao +2 位作者 JIANG Zu-cheng LI Feng LIAO Zhen-huan (College of Chemistry and Environmental Science, Wuhan University, Wuhan 430072, China) 《Wuhan University Journal of Natural Sciences》 CAS 2000年第1期83-88,共6页
A flow injection (FI) micro-column system coupled with high performance liquid chromatography (HPLC) was proposed for the pre-separation and determination of active organic component (ecdysterone) in traditional Chine... A flow injection (FI) micro-column system coupled with high performance liquid chromatography (HPLC) was proposed for the pre-separation and determination of active organic component (ecdysterone) in traditional Chinese medicine, Loulu. The factors influencing separation performance were investigated and optimized. Under the optimal conditions, the contents of ecdysterone in Loulu were determined by HPLC system using MeOH-H_2O (40: 60,V/V) as the mobile phase at a flow rate of 1. 0 mL/min. The calibration curve was linear in the range of 0. 5~ 100 mg/L of ecdysterone concentrations. The detection limit of the analyte was 0. 11mol/L(3) with a precision of 0. 38% RSD (n=7 f c= 10. 0 mg/L). The average recovery of the method was 98. 7%. The proposed method has been applied to determine ecdysterone in practical samples, and the determined values by both external standard method and standard addition method were in good agreement. Compared to the traditional solid extraction method, the system proposed has the advantages of simple procedure, good reproducibility, minimum volume requirement, reduction of matrix interference and low contamination risk. 展开更多
关键词 high performance liquid chromatography(HPLC) Flow injection analysis (FIA) ECDYSTERONE traditional Chinese medicine
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STUDY ON OPTIMIZATION OF HIGH PERFORMANCE CONCRETE ADMIXTURES 被引量:7
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作者 刘俊龙 麻海燕 +2 位作者 李强 陈树东 张云清 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2011年第2期206-210,共5页
Influences of admixtures on the workability and strength of high performance concrete (HPC) are in- vestigated. The types of investigated admixtures include naphthalene series high range water reducing agent, polyca... Influences of admixtures on the workability and strength of high performance concrete (HPC) are in- vestigated. The types of investigated admixtures include naphthalene series high range water reducing agent, polycarboxlic series high range water reduce agent and sodium sulfate hardening accelerating agent. Two kinds of curing condition, namely steam curing condition and standard curing condition, are adopted. The result shows that HPC, added with polycarboxlic series of high performance water reducer, has high workability and strength, while sodium sulfate accelerating agent causes poor workability and low strength. Thus for vapor-cured HPC and its formulations, naphthalene series high range water reducing agent with less sodium sulfate should be given pri- ority. Therefore, the differences of curing conditions should be considered when selecting HPC admixtures. 展开更多
关键词 high performance concrete high performance water reducer hardening accelerating agent SLUMP compressive strength
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High Performance Liquid Chromatography-Electrospray Ionization-Mass Spectrometric Analysis of Bilobalide and Ginkgolides in Ginkgo biloba L. Leaves 被引量:1
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作者 卢定强 韦萍 +1 位作者 欧阳平凯 陈钧 《Journal of Chinese Pharmaceutical Sciences》 CAS 2002年第2期26-30,共5页
The ginkgo terpenoids including bilobalide and ginkgolides are the main pharmaceutical components in the leaves or extracts of Ginkgo biloba L. In this paper, the analysis of bilobalide and ginkgolides in leaves of Gi... The ginkgo terpenoids including bilobalide and ginkgolides are the main pharmaceutical components in the leaves or extracts of Ginkgo biloba L. In this paper, the analysis of bilobalide and ginkgolides in leaves of Ginkgo biloba L. by high performance liquid chromatography (HPLC)-electrospray ionization (ESI)-mass spectrometry (MS) was carried out. The separation was performed on Inertsil ODS3 column with methanol-water (36:64) as mobile phase, with 1 mL·min -1 of flow rate at 35℃. Then the mass spectrum analysis was conducted by ZMD micromass electrospray ionization (ESI)-mass spectrometer (MS). The HPLC total ion chromatogram and selected ion chromatogram (with 325, 407, 423, 439 of m/z) of the sample and ESI-/MS mass spectra of the peaks in the chromatograms were obtained. So bilobalide, ginkgolide A, B, C and J in Ginkgo biloba L. leaves were identified. The method is easy and rapid, with a good accuracy. 展开更多
关键词 high performance liquid chromatography Electrospray ionization Mass spectrometry Ginkgo terpene lactones
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High Performance 70nm CMOS Devices
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作者 徐秋霞 钱鹤 +5 位作者 殷华湘 贾林 季红浩 陈宝钦 朱亚江 刘明 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2001年第2期134-139,共6页
A high performance 70nm CMOS device has been demonstrated for the first time in the continent, China. Some innovations in techniques are applied to restrain the short channel effect and improve the driving ability, ... A high performance 70nm CMOS device has been demonstrated for the first time in the continent, China. Some innovations in techniques are applied to restrain the short channel effect and improve the driving ability, such as 3nm nitrided oxide, dual poly Si gate electrode, novel super steep retrograde channel doping by heavy ion implantation, ultra shallow S/D extension formed by Ge PAI(Pre Amorphism Implantation) plus LEI(Low Energy Implantation), thin and low resistance Ti SALICIDE by Ge PAI and special cleaning, etc. The shortest channel length of the CMOS device is 70nm. The threshold voltages, G m and off current are 0 28V,490mS·mm -1 and 0 08nA/μm for NMOS and -0 3V,340mS·mm -1 and 0 2nA/μm for PMOS, respectively. Delays of 23 5ps/stage at 1 5V, 17 5ps/stage at 2 0V and 12 5ps/stage at 3V are achieved in the 57 stage unloaded 100nm CMOS ring oscillator circuits. 展开更多
关键词 high performance 70nm CMOS device S/D extension nitrided gate oxide Ge PAI SALICIDE
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An Improved High Fan-in Domino Circuit for High Performance Microprocessors
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作者 冯超超 陈迅 +1 位作者 衣晓飞 张民选 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2008年第9期1740-1744,共5页
An improved high fan-in domino circuit is proposed. The nMOS pull-down network of the circuit is divided into several blocks to reduce the capacitance of the dynamic node and each block only needs a small keeper trans... An improved high fan-in domino circuit is proposed. The nMOS pull-down network of the circuit is divided into several blocks to reduce the capacitance of the dynamic node and each block only needs a small keeper transistor to maintain the noise margin. Because we omit the footer transistor, the circuit has better performance than the standard domino circuit. A 64-input OR-gate implemented with the structure is simulated using HSPICE under typical conditions of 0.13μm CMOS technology. The average delay of the circuit is 63.9ps, the average power dissipation is 32.4μW, and the area is l15μm^2. Compared to compound domino logic, the proposed circuit can reduce delay and power dissipation by 55% and 38%, respectively. 展开更多
关键词 high fan-in domino logic high performance keeper transistor
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Determination of trans-resveratrol in mouse liver by high performance liquid chromatography
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作者 姚倩 侯世祥 +3 位作者 何希辉 张瑄 颜军 苟小军 《Journal of Chinese Pharmaceutical Sciences》 CAS 2008年第2期158-162,共5页
To develop a sensitive high performance liquid chromatography (HPLC) assay for the determination of trans-resveratrol in mouse liver. The whole liver of a mouse was removed from the body, homogenated, and extracted ... To develop a sensitive high performance liquid chromatography (HPLC) assay for the determination of trans-resveratrol in mouse liver. The whole liver of a mouse was removed from the body, homogenated, and extracted by ethyl acetate. The organic layer was isolated and evaporated to dryness, the residue was reconstituted in 0.2 mL mobile phase for centrifugation, and 50 uL of the supernatant was injected into the/-IPLC instrument. The sample was separated on a Shimadzu ODS column (150 mm × 4.6 mm, 5 um) at 35 ℃ and detected by ultraviolet (UV) detector at the wavelength of 305 nm. The mobile phase consisted of methanol and 0.1 mol/L acetic acid (4:6, v/v) with the flow-rote at 1 mL/min. The limit of detection was 3.0 ng/g in liver homogenate with a signal/noise ratio of 3:1. The linear range of the calibration curve was 5.0-120.0 ng/g. The mean recoveries at the concentrations of 6, 10 and 80 ng/g were 102%, 96.0% and 91.5%, respectively. The RSDs for inter- and intra-day assays were less than 5%. Compared with other reported methods, this method was faster and more sensitive. It was also proved to be of good linearity, selectivity, accuracy and precision, and can be efficiently applied to the pharmacoldnetic study of trans-resveratrol in mouse liver. 展开更多
关键词 high performance liquid chromatography TRANS-RESVERATROL Mouse liver
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INFLUENCE OF AIRCRAFT DEICER ON FREEZE-THAW DURABILITY OF HIGH PERFORMANCE CONCRETE
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作者 麻海燕 曹文涛 +2 位作者 白康 周鹏 韩丽娟 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2010年第4期306-312,共7页
The influence of glycol,the main composition of the most frequently used aircraft dicer,on the freeze-thaw durability of high performance concrete(HPC)is investigated.Freeze-thaw durability of HPC is tested by accel... The influence of glycol,the main composition of the most frequently used aircraft dicer,on the freeze-thaw durability of high performance concrete(HPC)is investigated.Freeze-thaw durability of HPC is tested by accelerated freeze-thaw test.Four kinds of the solution,i.e.,tap water,3.5% NaCl solution,glycol solutions,and a LBR-A type commercial aircraft deicer are employed.Results show that freeze-thaw durability of HPC exposed to glycol solutions is closely related to the solution concentrations.The failure of HPC exposed to 3.5% glycol solution is similar to that of those exposed to 3.5% NaCl solution,i.e.,serious surface scaling.While the damage of HPC exposed to 12.5%—25% glycol solutions is postponed.Compared with glycol solution,the commercial aircraft deicer has much more negative effects on HPC freeze-thaw durability compared with 3.5% NaCl solution.In the presence of commercial aircraft deicer for HPC subjected to freeze-thaw cycles,the deterioration is mainly due to scaling and spalling. 展开更多
关键词 concrete pavements DURABILITY aircraft deicer freeze-thaw cycles high performance concrete
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Detection of 36 antibiotics in coastal waters using high performance liquid chromatography-tandem mass spectrometry 被引量:13
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作者 那广水 顾佳 +4 位作者 葛林科 张蓬 王震 刘春阳 张琳 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2011年第5期1093-1102,共10页
Among pharmaceuticals and personal care products released into the aquatic environment, antibiotics are of particular concern, because of their ubiquity and health effects. Although scientists have recently paid more ... Among pharmaceuticals and personal care products released into the aquatic environment, antibiotics are of particular concern, because of their ubiquity and health effects. Although scientists have recently paid more attention to the threat of antibiotics to coastal ecosystems, researchers have often focused on relatively few antibiotics, because of the absence of suitable analytical methods. We have therefore developed a method for the rapid detection of 36 antibiotic residues in coastal waters, including tetracyclines (TCs), sulfanilamides (SAs), and quinolones (QLs). The method consists of solid-phase extraction (SPE) and liquid chromatography-tandem mass spectrometry (LC-MS/MS) analysis, using electrospray ionization (ESI) in positive mode. The SPE was performed with Oasis HLB and Oasis MCX cartridges. Chromatographic separation on a Cr8 column was achieved using a binary eluent containing methanol and water with 0.1% formic acid. Typical recoveries of the analytes ranged from 67.4% to 109.3% at a fortification level of 100 ng/L. The precision of the method, calculated as relative standard deviation (RSD), was below 14.6% for all the compounds. The limits of detection (LODs) varied from 0.45 pg to 7.97 pg. The method was applied to detemaine the target analytes in coastal waters of the Yellow Sea in Liaoning, China. Among the tested antibiotics, 31 were found in coastal 'waters, with their concentrations between the LOD and 212.5 ng/L. These data indicate that this method is valid for analysis of antibiotics in coastal waters. The study first reports such a large number of antibiotics along the Yellow Sea coast of Liaoning, and should facilitate future comprehensive evaluation of antibiotics in coastal ecosystems 展开更多
关键词 ANTIBIOTICS high performance liquid chromatography-tandem mass spectrometry SOLID-PHASEEXTRACTION coastal waters
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Novel method for the determination of five carbamate pesticides in water samples by dispersive liquid-liquid microextraction combined with high performance liquid chromatography 被引量:10
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作者 Zhi Mei Liu Xiao Huan Zang Wei Hua Liu Chun Wang Zhi Wang 《Chinese Chemical Letters》 SCIE CAS CSCD 2009年第2期213-216,共4页
A novel method for the determination of five carbamate pesticides (metolcarb, carbofuran, carbaryl, isoprocard and diethofencard) in water samples was developed by dispersive liquid-liquid microextraction (DLLME) ... A novel method for the determination of five carbamate pesticides (metolcarb, carbofuran, carbaryl, isoprocard and diethofencard) in water samples was developed by dispersive liquid-liquid microextraction (DLLME) coupled with high performance liquid chromatography-diode array detector (HPLC-DAD). Some experimental parameters that influence the extraction efficiency were studied and optimized to obtain the best extraction results. Under the optimum conditions for the method, the calibration curve was linear in the concentration range from 5 to 1000 ng mL^-1 for all the five carbamate pesticides, with the correlation coefficients (r^2) varying from 0.9984 to 0.9994. Good enrichment factors were achieved ranging from 80 to 177- fold, depending on the compound. The limits of detection (LODs) (S/N = 3) were ranged from 0.1 to 0.5 ng mL^-1. The method has been successfully applied to the analysis of the pesticide residues in environmental water samples. 展开更多
关键词 Carbamate pesticides high performance liquid chromatography Diode array detection Dispersive liquid-liquid microextraction Water samples
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Combined effect of steel fibres and steel rebars on impact resistance of high performance concrete 被引量:9
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作者 陈相宇 丁一宁 C.Azevedo 《Journal of Central South University》 SCIE EI CAS 2011年第5期1677-1684,共8页
The impact properties of normal concrete (NC) and reinforced concrete (RC) specimens,steel fibre reinforced concrete (SFRC) specimens and RC+SFRC specimens with different steel fibre dosages were investigated with the... The impact properties of normal concrete (NC) and reinforced concrete (RC) specimens,steel fibre reinforced concrete (SFRC) specimens and RC+SFRC specimens with different steel fibre dosages were investigated with the drop-weight impact test recommended by ACI Committee 544.The results indicate that the number of blows to final failure is greatly increased by addition of steel fibres.Moreover,the combination of steel fibres and steel rebars demonstrates a significant positive composite effect on the impact resistance,which results in the improvement in impact toughness of concrete specimens.In the view of variation of impact test results,the two-parameter Weibull distribution was adopted to analyze the experimental data.It is proved that the probabilistic distributions of the blows to first crack and to final failure of six types of samples approximately follow two-parameter Weibull distribution. 展开更多
关键词 impact resistance high performance concrete FIBRE Weibull distribution
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Looking Ahead——A New Generation of High Performance Refractory Ceramics 被引量:10
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作者 ZHONG Xiangchong(Zhengzhou University, 75 Daxue Road, Zhengzhou, Henan 450052, China) 《China's Refractories》 CAS 2002年第3期3-13,共11页
It is expected that in the new century, to cope with developments of new high temperature technologies , a new generation of high performance refractory ceramics will e-merge and flourish which should include the foll... It is expected that in the new century, to cope with developments of new high temperature technologies , a new generation of high performance refractory ceramics will e-merge and flourish which should include the following (1) oxide and nonoxide composites characterized by a unique combination of high hot strength , high thermal shock resistance and high corrosion resistance ; (2) free CaO bearing basic refractories capable of purifying molten metal for improving cleanliness and of absorbing contaminants from waste gases for reducing environmental pollution ; (3) free flowing zero cement castables with improved thermome-chanical properties , thermal shock resistance and corrosion resistance and gradient castables with varying matrix composition and varying texture. 展开更多
关键词 Review REFRACTORIES high performance OXIDES Nonoxides composites
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