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Journal of Environmental Sciences 2024年第12期146卷 15-27页

作者： Kai Zhao Ge Song Chaojie Lu Jiaqi Wang Ruiping Liu Chengzhi Hu State Key Laboratory of Environmental Aquatic Chemistry Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China University of Chinese Academy of Sciences Beijing 100049China Center for Water and Ecology State Key Joint Laboratory of Environment Simulation and Pollution ControlSchool of EnvironmentTsinghua UniversityBeijing 100084China

A large amount of sludge is inevitably produced during sewage ***(US)as anaerobic digestion(AD)pretreatment was implemented on different sludges and its effects on batch and semi-continuous AD performance were *** was ef-fective in sludge SCOD increase,size decrease,and CH_(4)production in the subsequent AD,and these effects were enhanced with an elevated specific energy *** indicated by semi-continuous AD experiments,the mean daily CH_(4)production of US-pretreated A^(2)O-,A^(2)O-MBR-,and AO-AO-sludgewere 176.9,119.8,and 141.7 NmL/g-VSadded,whichwere 35.1%,32.1%and 78.2%higher than methane production of their respective raw *** US of A^(2)O-sludge achieved preferable US effects and CH_(4)production due to its high organic con-tent andweak sludge structure *** response to US-pretreated sludge,amore diverse microbial community was observed in *** US-AD system showed negative net energy;however,it exhibited other positive effects,e.g.,lower required sludge retention time and less residual total solids for *** is a feasible option prior to AD to improve anaer-obic bioconversion and CH_(4)yield although further studies are necessary to advance it in practice.

关键词： ultrasonication Waste activated sludge Anaerobic digestion CH_(4)production Microbial community

Dimethylether production on zeolite catalysts activated by Cl^-,F^- and / or ultrasonication

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燃料化学学报 2016年第4期44卷 428-436页

作者： Sameh M.K.Aboul-Fotouh Noha A.K.Aboul-Gheit Mona A.Naghmash Chemistry Department Faculty of Education Ain Shams University Roxy Cairo 11757 Egypt Faculty of Science Chemistry Department Northern Border University Arar 91431 Kingdom of Saudi Arabia Egyptian Petroleum Research Institute Cairo 11787 Egypt

The chlorinated and fluorinated zeolite catalysts were prepared by the impregnation of zeolites( H-ZSM-5,H-MOR or H-Y) using two halogen precursors( ammonium chloride and ammonium fluoride) in this study. The influence of ultrasonic irradiation was evaluated for optimizing both halogen precursors for production of dimethylether( DME) via methanol dehydration in a fixed bed reactor. The catalysts were characterized by SEM,XRD,BET and NH3-TPD. The reaction conditions were temperatures from 100 to 300 ℃ and a WHSV = 15. 9 h-1. All halogenated catalysts showhigher catalytic activities at all reaction temperatures studied. However, the halogenated zeolite catalysts prepared under ultrasonic irradiation showhigher performance for DME formation. The chlorinated zeolite catalysts show higher activity and selectivity for DME production than the respective fluorinated versions.

关键词： ultrasonication DME zeolite Cl^- F^-

Effects of ultrasonication on the DBP formation and toxicity during chlorination of saline wastewater effluents

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Journal of Environmental Sciences 2022年第7期34卷 326-335页

作者： Yu Li Wanxin Li Xiangru Zhang Jingyi Jiang School of Environment Guangdong Provincial Key Laboratory of Chemical Pollution and Environmental Safety&MOE Key Laboratory of Theoretical Chemistry of EnvironmentSouth China Normal UniversityGuangzhou 510006China Department of Civil and Environmental Engineering Hong Kong University of Science and TechnologyHong KongChina

Chlorine disinfection of saline wastewater effluents rich in bromide and iodide forms relatively toxic brominated and iodinated disinfection byproducts(DBPs). ultrasonication is a relatively new water treatment technology, and it is less sensitive to suspended solids in wastewaters. In this study, we examined the effects of ultrasonication(in terms of reactor type and combination mode with chlorination) on the DBP formation and toxicity in chlorinated primary and secondary saline wastewater effluents. Compared with the chlorinated wastewater effluent samples without ultrasonication, ultrasonic horn pretreatment of the wastewater effluent samples reduced the total organic halogen(TOX) levels in chlorination by ~30%, but ultrasonic bath pretreatment of the wastewater samples did not significantly change the TOX levels in chlorination, which might be attributed to the higher energy utilization and decomposition extent of organic DBP precursors in the ultrasonic horn reactor. Moreover, the TOX levels in the chlorinated samples with ultrasonic horn pretreatment(USH–chlorination), simultaneous treatment(chlorination + USH) and subsequent treatment(chlorination–USH) were also significantly reduced, with the maximum TOX reductions occurring in the samples with ultrasonic horn pretreatment. A toxicity index was calculated by weighting and summing the levels of total organic chlorine, total organic bromine and total organic iodine in each treated sample. The calculated toxicity index values of the chlorinated wastewater effluent samples followed a descending rank order of “chlorination” > “chlorination + USH” > “chlorination–USH” > “USH–chlorination”, with the lowest toxicity occurring in the samples with ultrasonic horn pretreatment. Then, a developmental toxicity bioassay was conducted for each treated sample. The measured toxicity index values of the chlorinated wastewater samples followed the same descending rank order.

关键词： Disinfection byproducts DBPs Chlorination ultrasonication Developmental toxicity

Influence of clay concentration on the morphology and properties of clay-epoxy nanocomposites prepared by in-situ polymerization under ultrasonication

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Journal of University of Science and Technology Beijing 2008年第3期15卷 320-323页

作者： Jinwei Wang Xianghua Kong Lei Cheng Yedong He Beijing Key Laboratory for Corrosion Erosion and Surface Technology School of Materials Science and Engineering University of Science and TechnologyBeijing Beijing 100083 China

To investigate the effect of clay concentration on the structures and properties of bisphenol-A epoxy/nanoclay composites, three composites with organoclay concentrations of 2.5wt%, 5wt%, and 7.5wt% of the epoxy resin were prepared by in-situ polymerization under mechanical stirring followed by ultrasonic treatment. The clay aggregates on micro-scale indicate the absence of fully exfoliated nanocomposites. The layer space decreases with the increase of clay concentration, which suggests that the exfoliation would be constrained if more clay is added as the ultrasonic force is exerted. The thermal decomposition temperature remains almost unchanged with the increase of clay concentration. The glass transition temperature of the composites decreases slightly with the increase of clay concentration, whereas the storage modulus increases with the increase of clay concentration.

关键词： nanocomposite thermal properties mechanical properties clay concentration ultrasonication

Effect of ultrasonication on Optical Properties and Electronic States of Conjugated Polymer MEH-PPV

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Chemical Research in Chinese Universities 2008年第5期24卷 653-657页

作者： WU Meng YANG Gui-zhong WANG Meng WANG Wei-zhi WANG Min LIU Tian-xi Key Laboratory of Molecular Engineering of Polymers of Ministry of Education Department of Macromoleeular Science Laboratory of Advanced Materials Fudan University Shanghai 200433 P. R. China

Poly[2-methoxy-5-（2＇-ethyl-hexyloxy）-1,4-phenylene vinylene]（MEH-PPV）solutions with different concen-trations were prepared in chloroform for different ultrasonication *** ultraviolet absorption and photoluminescence（PL）spectra of the MEH-PPV solutions were measured,and the electronic states of the polymer chains under different experimental conditions were *** results showed that the effects of ultrasonication on the dilute and concentrated solutions were *** ultrasonication,the intensity of the absorption peak at 280 nm significantly decreased,relative to the absorption peak at 500 nm for both dilute and concentrated solutions,indicating that the proportion of the two excited states in the polymer chains had *** dilute MEH-PPV solutions,the blue-shifted absorption（at about 500 nm）and PL spectra show that ultrasonication also led to polymer chain degradation and thus shortened the effective conjugation *** concentrated solutions,however,the peak positions of the absorption spectra remained *** addition,the effects of the solution temperatures on the optical spectra for the MEH-PPV solutions were also discussed.

关键词： MEH-PPV Optical property Electronic state ultrasonication

Combination of salicylic acid and ultrasonication for alleviating chilling injury symptoms of longkong

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Food Quality and Safety 2022年第2期6卷 155-168页

作者： Paramee Noonim Karthikeyan Venkatachalam Faculty of Innovative Agriculture and Fishery Establishment Project Prince of Songkla University Surat Thani CampusMakham TiaMueangSurat ThaniThailand

Objectives Chilling injury is a prominent physiological disorder in longkong fruit pericarp when stored under 13℃for a prolonged *** study aimed to investigate the effects of individual salicylic acid(SA)and ultrasonication(US)treatments and of the combination salicylic acid and ultrasonication(SA-US)on alleviating the chilling injury symptoms in longkong fruit pericarp when in prolonged cold *** and Methods SA(1 mmol/L)and US(40 kHz,10 min at 90%amplitude,350 W)were used as individual and combined(SA-US)treat-ments to control the chilling injury in longkong *** various quality measures were checked every 2 d in longkong for up to 18 d of cold storage(13℃,90%relative humidity).Results The results revealed that the control fruits treated with water exhibited severe chilling injury symptoms followed in rank order by US,SA,and SA-US *** such as US and SA alone were more effective in controlling chilling injuries than control,while only minimal signifi-cant differences were noticed between *** the other hand,the longkong pericarp treated with the SA-US combination had significantly increased antioxidant enzyme(superoxide dismutase and catalase)activities and decreased levels of membrane lytic(phospholipase D and lipoxygenase)enzymes and browning-inducing enzymes(phenylalanine ammonia lyase and polyphenol oxidase).Consequently,in the longkong pericarp,the chilling injury index,electrolytic leakage,respiration rate,weight loss,firmness,malondialdehyde content,changes in unsaturated and saturated fatty acid contents,and reactive oxygen species were significantly controlled by this *** The present study concludes that longkong fruit treatment with a combination of US and SA is an excellent alternative for control-ling the chilling injury symptoms and extending the shelf-life.

关键词： Longkong cillig injury ultrasonication salicylic acid biochemic al qualities

Transformation of maize embryogenic calli mediated by ultrasonication and regeneration of fertile transgenic plants

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Science China(Life Sciences) 1997年第3期40卷 316-322页

作者：张宏王国英谢友菊戴景瑞许宁赵南明李太源田颖川乔利亚莽克强 School of Biological Sciences Beijing Agricultural University Beijing 100094 China Tsinghua University Beijing 100084 China Tsinghua University Beijing 100084 China Institute of Microbiology Chinese Academy of Sciences Beijing 100080 China

An insecticidal protein gene isolated from Bacillus thuringiensis was transferred into maize by using ultrasonication. The fertile transgenic plants and their progeny were obtained. The Southern hybridization results indi-cated that the foreign gene had integrated into the maize genome. It has been found that the acoustic intensity and the duration of treatment are the important parameters influencing transformation efficiency by ultrasonication. The maxi-mum relative transformation frequency of 34. 1 % was achieved after 30 min of sonication at 0. 5 W/cm2 acoustic inten-sity. With appropriate parameters the ultrasonication ran make a number of micropores formed on the cell surface and minimize the treatment damage to the foreign DNA molecules, thus facilitating the DNA molecules to enter the cells.

关键词： maize transformation ultrasonication transgenic plants.

Synthesis of Nanostructured TiO<sub>2</sub>Photocatalyst with ultrasonication at Low Temperature

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Journal of Materials Science and Chemical Engineering 2015年第1期3卷 29-36页

作者： Yong Tao Zhenan Han Zuolian Cheng Qishan Liu Fengxia Wei Kok Eng Ting Xi Jiang Yin Advanced Materials Technology Center Singapore Polytechnic Singapore City Singapore School of Chemical & Life Sciences Singapore Polytechnic Singapore City Singapore School of Architecture & the Building Environment Singapore Polytechnic Singapore City Singapore

A thin film TiO2 in hierarchical nano-structure with high photocatalytic activities was synthesized in simple steps with ultrasonication. The crystal structure and morphology of the photocatalyst were investigated by X-ray diffraction (XRD) and high-resolution field emission scanning electron microscope (FE-SEM). In the present work, nanostructured TiO2 was directly formed onto a Ti substrate via a solution approach. This nanostructured TiO2 photocatalyst can be reused and will not generate secondary contamination to treated water. The photocatalytic activity of the synthesized TiO2 photocatalyst was evaluated by the degradation of phenol under UVC irradiation in water and was compared with the general sol-gel derived TiO2 films as well as a commercial DP-25 TiO2 coating. It was found that the synthesized nanostructured TiO2has significantly high and stable photocatalytic activity.

关键词： Photocatalysis ultrasonication Semiconductor Titanium Dioxide Nanostructure

Monosaccharide Recovery from Peat and Peatified Wood by ultrasonication Pretreatment and Hydrothermal Treatment

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International Journal of Clean Coal and Energy 2017年第2期6卷 31-39页

作者： Moriyasu Nonaka Tsuyoshi Hirajima Satoshi Kumagai Department of Earth Resources Engineering Faculty of Engineering Kyushu University Fukuoka Japan Faculty of Agriculture Department of Applied Biochemistry and Food Science Saga University Saga Japan

Peat and peatified wood are significant carbohydrate resources in tropical rainforests. The carbohydrates of cellulose and hemicellulose are important sources of monosaccharides for both vital activities and industrial applications, such as furan production of furfural and hydroxymethyl furfural. Hydrothermal treatment at 200°C and ultrasonic irradiation pretreatment were used to recover monosaccharides from the abovementioned resources. The monosaccharide recovery from peat was shown to be higher than that from peatified wood. The conversion to organic acids is considered to proceed rapidly because acids are always detected with monosaccharides. This conversion is outstripped by the organic acid-to-gas reaction for treatment times longer than 20 min. The monosaccharide recovery from peatified wood was improved by the ultrasonication pretreatment. It is considered that ultrasonic irradiation broke down lignin blockages, enabling water molecules to access the carbohydrates more easily in the subsequent hydrothermal treatment.

关键词： Peat Peatified Wood Hydrothermal Treatment ultrasonication Monosaccharide

Low Frequency ultrasonication Induced Antitumor Effect in 5-Aminolevulinic Acid Treated Malignant Glioma

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Journal of Cancer Therapy 2013年第1期4卷 170-175页

作者： Fumio Yamaguchi Takayuki Asakura Hiroshi Takahashi Takayuki Kitamura Akira Teramoto Department of Neurosurgery Nippon Medical School Tokyo Japan

We investigated the feasibility of sonodynamic therapy for glioma by low frequency ultrasoundwith5-aminolevulinic acid (5-ALA), a precursor of protoporphyrin IX (PpIX) in heme synthetic process. In vivo tumor model was made by inoculating human glioma cell line U87-MG subcutaneously in nude mice. The tumor was sonicated by 25-kHz ultrasound 4 hours following administration of 5-ALA. The tumor size decreased in 5-ALA administered (ALA(+)US(+)) mice, while increased in non-5-ALA administrated (ALA(-)US(+)) mice and non-sonicated mice (ALA(+)US(-)). The immunohistochemical analysis revealed an apoptotic change in tumor tissue of ALA(+)US(+) mice. The results showed the therapeutic effect of 25 kHz ultrasound for the glioma in 5-ALA administered tumor-bearing mice by inducing apoptotic change of tumor cells. This is a first report to elucidate the feasibility of therapeutic use of 25 kHz, relatively low frequency, ultrasound in sonodynamic therapy using 5-ALA as a sonosensitizer precursor. The utilization of this frequency will contribute to the development of sonodynamic therapy for gliomas and the spread of this technique in many hospitals that possess ultrasonic aspirators.

关键词： Glioma Sonodynamic Therapy 5-Aminolevulinic Acid Protoporphyrin IX ultrasonication