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Engineering 2021年第11期7卷 1603-1610页

作者： yong Cai Guang-wen Chu yong Luo Meng-Jun Su Bao-Ju Wang Bao-Chang Sun Jian-feng Chen State Key Laboratory of Organic–Inorganic Composites Beijing University of Chemical TechnologyBeijing 100029China Research Center of the Ministry of Education for High-Gravity Engineering and Technology Beijing University of Chemical TechnologyBeijing 100029China

Pollution involving pharmaceutical components in bodies of water is an increasingly serious environmental *** discharge for the degradation of antibiotics is an emerging technology that may be relevant toward addressing this *** this work,a plasma-assisted rotating disk reactor(plasma-RDR)and a photocatalyst—namely,titanium dioxide(TiO_(2))—were coupled for the treatment of metronidazole(MNZ).Discharge uniformity was improved by the use of a rotating electrode in the plasma-RDR,which contributed to the utilization of ultraviolet(UV)light radiation in the presence of TiO_(2).The experimental results showed that the degradation efficiency of MNZ and the concentration of generated hydroxyl radicals respectively increased by 41%and 2.954 mg∙L^(-1) as the rotational speed increased from 0 to 500 r∙min^(-1).The synergistic effect of plasma-RDR plus TiO_(2) on the generation of hydroxyl radicals was *** intermediate products were identified using three-dimensional(3D)excitation emission fluorescence matrices(EEFMs)and liquid chromatography-mass spectrometry(LC-MS),and a possible degradation pathway is proposed *** plasma-catalytic process has bright prospects in the field of antibiotics degradation.

关键词： Plasma-assisted rotating disk reactor Pulsed discharge Metronidazole Degradation TiO_(2)

Axial ligands tailoring the ORR activity of cobalt porphyrin

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Science Bulletin 2019年第16期64卷 1158-1166页

作者： Yue Zhou yong-Fang Xing Jing wen Hai-Bo Ma feng-Bin Wang Xing-Hua Xia School of Chemistry and Chemical Engineering Nanjing University

In an effort to provide visualization and understanding to the electronic ‘‘push effect' of axial ligands on the catalytic activity of cobalt macrocyclic molecules, we design a simple model system involving an[5,10,15,20-tetrakis(4-methoxyphenyl)porphyrin]cobalt(II)(TMMPCo) monolayer axially-coordinated on thiol ligand modified Au electrode and explore the activity of the axial-ligand coordinated TMPPCo toward oxygen reduction reaction(ORR) in acidic medium. Three different ligands, with a decreasing order of coordinating ability as: 4-mercaptopyridine(MPy) > 4-aminothiolphenol(APT) > 4-mercaptobenzonitrile(MBN) are used and a maximum difference in ORR onset potential of 80 mV is observed between the MPy(highest onset potential) and MBN systems(lowest onset potential). The ORR activity of TMPPCo increases with the increase in binding strength of the axial ligand. A detailed mechanism study reveals that ORR on the three ligand coordinated TMPPCo systems shares the same2-electron mechanism with H2 O2 as the terminal product. Theoretical calculation into the structure of the ligand coordinated cobalt porphyrins uncovers the variation in atomic charge of the Co(II) center and altered frontier molecular orbital distribution among the three ligand systems. Both properties have great influence on the back-bonding formation between the Co(II) center and O2 molecules, which has been suggested to be critical toward the O2 adsorption and subsequent activation process.

关键词： Oxygen reduction reaction(ORR) Cobalt porphyrin Axial ligands Push effect

Response of Nematodes in a Hapli-Udic Argosol to Urea Amended with Urease and Nitrification Inhibitors

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Pedosphere 2006年第4期16卷 428-434页

作者： HUA Jian-feng JIANG yong LIANG wen-Ju Soil Ecology Laboratory Institute of Applied Ecology Chinese Academy of Sciences Shenyang 110016 （China） Graduate School of the Chinese Academy of Sciences Beijing 100039 （China）

Effects of urea amended with urease and nitrification inhibitors on soil nematode communities were studied in a Hapli- Udic Argosol （Cambisol, FAO） in Liaoning Province of Northeast China. A completely random design with four treatments, i.e., conventional urea （CU）, slow-release urea amended with a liquid urease inhibitor （SRU1）, SRU1 ＋nitrification inhibitor dicyandiamide （SRU2）, and SRU1 ＋ nitrification inhibitor 3,5-dimethylpyrazole （SRU3） and four replicates were applied. Thirty-nine genera of nematodes were identified, with Cephalobus and Aphelenchus being dominant; and in all treatments, the dominant trophic group was bacterivores. In addition, during the growth period of spring wheat （Triticum aestivum L.）, soil urease activity was lower in SRUs than in CU. The numbers of total nematodes and bacterivores at wheat heading and ripening stages, and omnivores-predators at ripening stage were higher in SUR3 than in CU, SRU1 and SRU2 （P 〈 0.05）.

关键词： Hapli-Udic Argosol nitrification inhibitor slow-release urea soil nematodes urease inhibitor

Dissipation and residue of ethephon in maize field

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Journal of Integrative Agriculture 2015年第1期14卷 106-113页

作者： DONG Jian-nan MA yong-qiang LIU feng-mao JIANG Nai-wen JIAN Qiu Department of Applied Chemistry College of ScienceChina Agricultural University Institute for the Control of Agrochemicals Ministry of Agriculture

A rapid and reliable method was developed for analysis of ethephon residues in maize, in combination with the investigation of its dissipation in field condition and stabilities during the sample storage. The residue analytical method in maize plant, maize kernel and soil was developed based on the quantification of ethylene produced from the derivatization of ethephon residue by adding the saturated potassium hydroxide solution to the sample. The determination was carried out by using the head space gas chromatography with flame ionization detector （HS-GC-FID）. The limit of quantification （LOQ） of the method for maize plant was 0.05, 0.02 mg kg-1 for maize kernel and 0.05 mg kg-1 for soil, respectively. The fortified recoveries of the method were from 84.6-102.6%, with relative standard deviations of 7.9-3.8%. Using the methods, the dissipation of ephethon in maize plant or soil was investigated. The half life of ethephon degradation was from 0.6 to 3.3 d for plant and 0.7 to 5.7 d for soil, respectively. The storage stabilities of ethephon residues were determined in fresh and dry kernels with homogenization and without homogenization process. And the result showed that ethephon residues in maize kernels were stable under-18℃ for 6 mon. The results were helpful to monitor the residue dissipation of ethephon in the maize ecosystem for further ecological risk assessment.

关键词： ethephon residue maize degradation storage stability

Elemental Composition and Geochemical Characteristics of Iron-Manganese Nodules in Main Soils of China

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Pedosphere 2006年第1期16卷 72-81页

作者： TAN wen-feng LIU Fan LI yong-Hua HU Hong-Qing HUANG Qiao-Yun College of Resources and Environment Huazhong Agricultural University Wuhan 430070 （China）. Institute of Geographical Sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100101（China）

Elemental composition and geochemical characteristics of iron-manganese nodules from nine main soils in China were studied by chemical and multivariate statistical analyses to better understand the reactions and functions of iron-manganese nodules in soils and sediment. Compared to the corresponding soils, Mn, Ba, Cd, Co and Pb had strong accumulation, Ni had moderate accumulation, while Ca, Cu, Fe, Na, P, Sr and Zn accumulated to a minor degree in the iron-manganese nodules. In contrast, Si, Al, K, Mg and Ti were reduced in the iron-manganese nodules. The contents of Ba, Cd, Co, Cu, Ni, Pb and Zn were positively and significantly correlated with that of MnO2 in the iron-manganese nodules, while the contents of Cr, Cu, Ni, Pb and Zn were positively and significantly correlated with that of Fe2O3 in soils. Based on a principle component analysis, the elements of iron-manganese nodules were divided into four groups: 1) Mn, Ba, Cd, Co, Cu, Li, Ni, Pb and Zn that were associated with Mn oxides, 2) Fe, Cr and P that were associated with Fe oxides, 3) Si, K, and Mg that were included in the elemental composition of phyllosilicate, and 4) Ca, Na, Al and Ti that existed in todorokite, birnessite, lithiophorite and phyllosilicate. It was suggested that accumulation, mineralization and specific adsorption were involved in the formation processes of soil iron-manganese nodules.

关键词： elemental composition geochemical characteristics iron-manganese nodule soil

Dynamic Recrystallization Behavior and Microstructure Evolution of AISI 304N Stainless Steel

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Journal of Iron and Steel Research International 2013年第10期20卷 107-112页

作者： WANG Chang-jun feng Han ZHENG wen-jie SONG Zhi-gang yong Qi-long Central Iron and Steel Research Institute

Dynamic recrystallization of 304N stainless steel was investigated at deformation temperatures of 900- 1 300 ℃ and strain rates of 0.01 10 s by a Gleeble-1500 thermo-mechanical simulator. And the microstructure evolu lions of specimens with different deformation temperatures were observed by using a transmission electron micro scope. Results indicated that compared with conventional AISI 304 austenitie stainless steel, 304N stainless steel has higher deformation resistance force and deformation activation energy under similar conditions. In addition, the flow stress constitutive equation of 304N stainless steel was obtained by regression analysis of experimental stress strain data, and the calculated values proposed by the mathematical model agree well with the experimental results.

关键词： 304N stainless steel dynamic recrystallization constitutive equation microstructure evolution

New route to synthesize preceramic polymers for zirconium carbide

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Chinese Chemical Letters 2012年第9期23卷 1075-1078页

作者： Xue Yu Tao wen feng Qiu Hao Li Tong Zhao Xian yong Wei School of Materials Science and Engineering China University of Mining and TechnologyChina Xuzhou 221116 Laboratory of Advanced Polymer Materials lnstute of ChemistryChinese Academy of SciencesChina Beijing 100190 School of Chemical Engineering and Technology China University of Mining and TechnologyChina Xuzhou 221116

A preceramic polymer, polyzirconosaal （PZSA）, was synthesized by the ligand-exchange reaction between polyzirconoxane （PZO） and salicyl alcohol （SA）. The precursor was air-stable and exhibited excellent solubility and rheology. These properties are useful for the processing of C/C-ZrC composites v/a precursor infiltration and pyrolysis （PIP） process. The polymer to ceramic conversion was investigated by TG, XRD and TEM. Nanosized ZrC was formed by pyrolysis of this precursor at 1300 ℃ in argon with ceramic yield of 57.8%.

关键词： Preceramic polymer Zirconium carbide Precursor infiltration and pyrolysis

A method of determining nonlinear large strain consolidation parameters of dredged clays

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Water Science and Engineering 2014年第2期7卷 218-226页

作者： Yu-peng CAO Xue-song Wang Long DU Jian-wen Ding yong-feng DENG Institute of Geotechnical Engineering Southeast University Municipal Facilities Authority Weifang Economic Development Zone

A method of obtaining the large strain consolidation parameters of dredged clays considering the influence of the initial water content is investigated in this study. According to the test results of remolded clays with high initial water contents reported by Hong et al. （2010）, a relationship between the void ratio （e） and effective stress （a3 is established. Furthermore, based on the available permeability data from the literature, a new relationship between the permeability coefficient （k） and the ratio （e/eL） of the void ratio to the void ratio at the liquid limit （eL） is proposed. The new proposed expression considering the initial water content improves the e-k equation established by Nagaraj et al. （1994）. Finally, the influence of the initial void ratio and effective stress on the large strain consolidation coefficient g（e） defined by Gibson et al. （1981） and k/（1 ＋e） in large strain analysis is discussed. The results show that, under a constant effective stress, the value of k/（1 ＋e） increases with the initial void ratio. The large strain consolidation coefficient shows the law of segmentation change, which decreases with the increase of the effective stress when the effective stress is less than the remolded yield stress, but increases rapidly with the effective stress when the effective stress is larger than the remolded yield stress.

关键词： initial void ratio permeability large strain consolidation parameter remolded yieldstress dredged clay

Facile three-component synthesis and insecticidal evaluation of hexahydroimidazo[1,2-a]pyridine derivatives

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Chinese Chemical Letters 2015年第1期26卷 1-5页

作者： Ye-feng Fan wen-wen Zhang Xu-Sheng Shao Zhi-Ping Xu Xiao-yong Xu Zhong Li Shanghai Key Lab of Chemistry Biology School of PharmacyEast China University of Science and Technology Shanghai Collaborative Innovation Center for Biomanufacturing Technology

A series of new hexahydroimidazo[1,2-a]pyridine derivatives were synthesized via convenient and practical three-component reactions. Preliminary bioassays showed that majority of the target compounds exhibited moderate to excellent insecticidal activity against cowpea aphids （Aphis craccivora）. Among them, compound 91 demonstrated significant activity with LCso value of 0.00918 mmol/L which was about 3.8-fold higher than that of imidacloprid （IMI）. Furthermore, the study of stereostructure-activity relationship of four isomers of 9k indicated that configuration played a key role in insecticidal activity of these compounds.

关键词： Neonicotinoids Hexahydroimidazo[ 1,2-a]pyridine Three-component reaction Configuration Insecticidal activity

Intra-abdominal inflammatory pseudotumor-like follicular dendritic cell sarcoma associated with paraneoplastic pemphigus: A case report and review of the literature

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World Journal of Clinical Cases 2020年第14期8卷 3097-3107页

作者： Jia-Yi Zhuang Fang-Fei Zhang Qing-wen Li yong-feng Chen Department of Dermatology Dermatology HospitalSouthern Medical University/Guangdong Provincial Dermatology HospitalGuangzhou 510091Guangdong ProvinceChina

BACKGROUD Follicular dendritic cell(FDC)sarcomas are rare neoplasms that occur predominantly in the lymph *** can also occur *** FDC sarcomas most commonly present as solitary *** pseudotumor(IPT)-like FDC sarcomas,a subcategory of FDC sarcomas,are rarer than other sarcoma *** are composed of spindle or ovoid neoplastic cells and exhibit an admixture of plasma cells and prominent lymphoplasmacytic *** pemphigus(PNP),also known as paraneoplastic autoimmune multiorgan syndrome,is a rare autoimmune bullous disease that is associated with underlying *** has a high mortality,and its early diagnosis is usually *** SUMMARY We describe a 27-year-old woman who presented with stomatitis,conjunctivitis,and skin blisters and erosions as her first symptoms of PNP with an intraabdominal IPT-like FDC *** patient underwent surgical tumor resection and received tapering oral corticosteroid *** showed no recurrence at the 1-year *** IPT-like FDC sarcomas are rare underlying neoplasms that have an uncommon association with ***-associated FDC sarcomas predominantly occur in intra-abdominal sites and suggest a poor *** resection is an essential and effective treatment for PNP and primary and recurrent FDC sarcomas.

关键词： Inflammatory pseudotumor-like follicular dendritic cell sarcoma Paraneoplastic pemphigus Follicular dendritic cell sarcoma Resection Case report