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Influences of ultrasonic irradiation on the morphology and structure of nanoporous Co nanoparticles during chemical dealloying

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Progress in Natural Science:Materials International 2016年第6期26卷 562-566页

作者： Hui Li Mu Zhu Yu Pang Huanhuan Du Tong Liu Key Laboratory of Aerospace Materials and Performance(Ministry of Education) School of Materials Science and EngineeringBeihang University

The Co-61.8 wt% Al nanoparticles of 45 nm were prepared by hydrogen plasma-metal reaction（HPMR）method. The nanoparticles display core shell structure with Al13Co4and CoAl core and aluminum oxide shell（about 2 nm）. Under ultrasonic irradiation, nanoporous fcc-Co nanoparticles were produced successfully by chemically dealloying the Co-Al nanoparticles at room temperature, whereas, without ultrasonic irradiation CoAl phase could hardly react with sodium hydroxide solution. At 323 K the Co-Al nanoparticles could be dealloyed to fcc-Co and hcp-Co phases even without ultrasonic irradiation. The surface area of the dealloyed nanoparticles under ultrasonic irradiation was larger than that of the dealloyed sample without ultrasonic irradiation at the same temperature. It is believed that the microjet and shock-wave induced by ultrasonic irradiation give rise to particles size reduction, interparticle collision and surface cleaning, and accelerate the dealloying process and the phase transformation.

关键词： Nanoporous nanoparticles Co ultrasonic irradiation Chemical dealloying Microstructure

Degradation of bisphenol-A using ultrasonic irradiation assisted by low-concentration hydrogen peroxide

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Journal of Environmental Sciences 2011年第1期23卷 31-36页

作者： Kejia Zhang Naiyun Gao Yang Deng Tsair Fuh Lin Yan Ma Lei Li Minghao Sui State Key Laboratory of Pollution Control and Resource Reuse Tongji University Shanghai 200092 China Department of Earth and Environmental Studies Montclair State University Montclair New Jersey 07043 USA Department of Environmental Engineering and Sustainable Environment Research Center 'National' Cheng Kung University Tainan 70101 Taiwan

This study investigated the degradation of bisphenol-A （BPA） by ultrasonic irradiation in the presence of different additives （H2O2, air bubbles and humic acid） under various operating conditions, i.e., ultrasonic frequency, power intensity and power density. The results demonstrated that the BPA degradation followed pseudo first-order kinetics under different experimental conditions. The optimum power intensities were 0.9, 1.8, and 3.0 W/cm2 at the frequencies of 400, 670, and 800 kHz, respectively. At the fixed frequency （800 kHz）, the degradation rate of BPA was shown proportional to the increase of power density applied. With this manner, the BPA sonolysis could be facilitated at H202 dosage being lower than 0.1 mmol/L; while BPA degradation was hindered at H202 concentration in excess of 1 mmol/L. Additionally, BPA removal was shown to be inhibited by the presence of aeration and humic acid during ultrasonic irradiation. The present study suggested that the degradation rate of BPA assisted by ultrasonic irradiation was influenced by a variety of factors, and high BPA removal rate could be achieved under appropriate conditions.

关键词： bisphenol-A (BPA) ultrasonic irradiation power density additives

Decomposition of Organic Compounds in Coke Plant Wastewater by ultrasonic irradiation and Its Combined Process

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Chemical Research in Chinese Universities 2004年第4期20卷 421-428页

作者： XUJin-qiu JIAJin-ping WANGJing-wei SchoolofEnvironmentalScienceandEngineering ShanghaiJiaotongUniversityShanghai200240P.R.China DepartmentofEnvironmentalEngineering ShanghaiSecondPoly-technicUniversityShanghai201206P.R.China

The paper deals with the degradation of the organic compounds in the coke plant wastewater by the combined process of ultrasonic irradiation and activated sludge. The influence factors of the ultrasonic degradation effect such as air atmosphere, initial concentration, ultrasonic power density and the category and consumption of catalyst were investigated. A water quality model was used to explain the degradation of different kinds of organic compounds in the coke plant wastewater by ultrasonic irradiation. After the wastewater was treated by the combined process of ultrasonic irradiation and activated sludge, the COD degradation efficiency was 95.74%, which is 63.49% higher than that by the process of activated sludge alone.

关键词： Coke plant wastewater Organic compounds ultrasonic irradiation Activated sludge Degradation Water quality model

Modifying Behaviors of ultrasonic irradiation and Rare Earth Metal Cerium on Electroless Co-Ni-B Alloy Coating

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Journal of Rare Earths 2003年第S1期21卷 185-189页

作者：宣天鹏章磊黄芹华 Material Science and Engineering Institute Hefei University of Technology

By plasma transmitting spectrograph,electron energy spectrometry,X-ray diffractometry,transmission electron microscopy and micro-hardometry,the effects of ultrasonic irradiation and rare earth metal cerium on the depositing speed,chemical composition,crystal structure and microhardness of electroless Co-Ni-B alloy coating were inspected and analyzed. The results show that cerium and ultrasonic irradiation can evidently raise the depositing speed of electroless Co-Ni-B alloy. The cerium content of electroless Co-Ni-B-Ce alloy coating also increases after ultrasonic irradiation applied to electroless Co-Ni-B plating process. Under the action of ultrasonic irradiation and rare metal cerium,the chemical composition of electroless Co-Ni-B alloy coating is changed. Electroless Co-Ni-B alloy with amorphous structure is transformed to electroless Co-Ni-B-Ce alloy with microcrystalline in general state and electroless Co-Ni-B-Ce alloy with crystalline structure in ultrasonic irradiation. In this way microhardness of the coatings increases remarkably.

关键词： metal materials ultrasonic irradiation cerium electroless plating cobalt crystal structure rare earths

Efficient Synthesis of Glycosylated Matijin-Su Derivatives via ultrasonic irradiation

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Chinese Journal of Chemistry 2016年第12期34卷 1353-1359页

作者： Guangping Liang Zhanxing Hu Jie Yuan Guangyi Liang Bixue XU College of Pharmacy Jinan University Guangzhou Guangdong 510632 China Key Laboratory of Chemistry for Natural Products of Guizhou Province and Chinese Academy of Sciences Guiyang Guizhou 550002 China

Matijin-Su （1） is a phenylalanine dipeptide compound with anti-hepatitis B virus （HBV） activity. Previous re- ports suggest that the synthesis of glycosylated Matijin-Su derivatives needs at least 10 steps. To simplify the syn- thetic procedure, we have developed a shorter and more efficient method for the preparation via ultrasound irradiation. Two galactopyranosylated （2） and two glucopyranosylated （3） derivatives were synthesized in 6 or 7 steps. The overall yields for the total synthesis of galactopyranosylated derivatives were markedly increased to 39% （2a） or 22% （2b）. And the yields for glucopyranosylated derivatives also reached 29% （3a） or 16% （3b）.

关键词： Matijin-Su dipeptide glycosylation ultrasonic irradiation

Sonication method synergism with rare earth based nanocatalyst:preparation of NiFe_(2–x)Eu_xO_4 nanostructures and its catalytic applications for the synthesis of benzimidazoles,benzoxazoles,and benzothiazoles under ultrasonic irradiation

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Journal of Rare Earths 2017年第4期35卷 374-381页

作者： Abolfazl Ziarati Ali Sobhani-Nasab Mehdi Rahimi-Nasrabadi Mohammad Reza Ganjali Alireza Badiei School of Chemistry College of Science University of TehranTehran ***lran Young Researchers and Elite Club Arak BranchIslamic Azad UniversityArak ***Iran Faculty of Pharmacy Baqiyatallah University of Medical SciencesTehran ***lran Department of Chemistry Imam Hossein UniversityTehran ***lran Center of Excellence in Electrochemistry University of TehranTehran *** lran

A simple and practical ultrasonically synthetic strategy for the preparation of rare-earth based catalyst, nanostructured NiFe2-xEuxO4 was developed. The structtre of NiFe2-xEuxO4 was characterized by various analyses such as X-ray diffraction （XRD）, scanning electron microscopy （SEM） and fourier transform infrared spectroscopy （FT-IR）. The catalytic performance of NiFe2-xEuxO4 was evaluated for the synthesis of benzimidazoles, benzoxazoles and benzothiazoles under ultrasonic irradiation. All reactions were completed in short times and all products were obtained in good to excellent yields in presence of the rare-earth based catalyst. Besides, NiFe2-xEuxO4 could be recovered for 6 times without noticeably decreasing the catalytic activity.

关键词： rare earths organic reactions nanocatalyst ultrasonic irradiation

One-pot synthesis of 2,5-disubstituted-1,3,4-thiadiazoles under ultrasonic irradiation

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Chinese Chemical Letters 2007年第9期18卷 1047-1048页

作者： Ying Jun Li Ya Zhen Sun Yong Ting Xu Kun Jin Li Ping Wen Ni Bo Hou Xiao Xiao Sun College of Chemistry and Chemical Engineering Liaoning Normal University Dalian 116029 China State Key Laboratory of Fine Chemicals Dalian University of Technology Dalian 116012 China

A facile one-pot synthesis of 2,5-disubstituted-1,3,4-thiadiazoles was achieved by ultrasonic irradiation of a mixture of 1-naphthylacetyl chloride, NH4CNS, CH2Cl2 and PEG-400 for 1.5 h at 10–20 °C and subsequent irradiation for 1.5 h in the presence of N-arylglycine hydrazides. This method requires short time and gives thiadiazoles in high yields.

关键词： One-pot ultrasonic irradiation 2,5-Disubstituted-1,3,4-thiadiazoles Synthesis

Degradation of chlorothalonil by ultrasonic irradiation:Kinetics and impact factors

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Journal of Central South University 2011年第4期18卷 1068-1073页

作者：郭洪光高乃云黎雷金玄雄陈喆 State Key Laboratory of Pollution Control and Resources Reuse Tongji University

Factors on degradation of chlorothalonil(CLT) in water by high frequency ultrasonic irradiation were *** effects of initial concentration of chlorothalonil,dosages of tertiary butyl alcohol,humic acid and initial pH value on degradation of chlorothalonil,as well as the reaction mechanism were *** results reveal that chlorothalonil could be effectively degradated by ultrasonic *** reaction constant value kapp decreased from 0.014 1 to 0.010 2 min-1 with the initial concentration increasing from 50 to 400 μg/L during 180 min *** butyl alcohol had negative effect on chlorothalonil degradation,while lower concentration of humic acid promoted the sonolysis,and kapp declined with the further concentration *** kapp varied little when the pH value ranged from 3.10 to *** may be concluded that mechanical and pyrolysis process played main roles on the degradation of chlorothalonil in ultrasonic irradiation rather than ·OH *** electrical energy per order(EEo) values for sonolysis degradation of CLT were also calculated to evaluate the cost of the process.

关键词： ultrasonic irradiation chlorothalonil kinetics impact factors

Phase Transfer Catalyzed Synthesis under ultrasonic irradiation and Bioactivity of N'-(4,6-Disubstituted-pyrimidin-2-yl)-N-(5-aryl-2-furoyl) Thiourea Derivatives

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有机化学 2004年第Z1期24卷 237-238页

作者： KE,Shao-Yong WEI,Tai-Bao XUE,Si-Jia DUAN,Li-Ping GUO,Yan-Ling Department of Chemistry Shanghai Normal University Shanghai 200234 Department of Chemistry Northwest Normal University Lanzhou 730070 Department of Chemistry Shanghai Normal University Shanghai 200234 Department of Chemistry Shanghai Normal University Shanghai 200234 Department of Chemistry Shanghai Normal University Shanghai 200234

　　Acylthiourea derivatives are useful as pesticides, herbicides, fungicides and regulator for plant growth, and also as important intermediates in the organic synthesis. In recent years, phase transfer catalysis reaction technique has been widely recognized as an efficient synthetic tool and attracted much attention. In view of these observations, a series of 5-aryl-2-furoyl thioureas containing substituted pyrimidine ring were synthesized using PEG-400 as solid-liquid phase transfer catalyst under ultrasonic irradiation. All of the new compounds have been exactly determined by IR, 1H NMRand elemental analysis.……

关键词： phase transfer catalyst ultrasonic irradiation elemental analysis organic synthesis plant growth