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Journal of environmental Protection 2019年第4期10卷 562-576页

作者： helen Ataikiru Felix e. Okieimen College of education Warri Nigeria Department of Chemistry University of Benin Benin City Nigeria

Heavy metals are non-biodegradable. They accumulate in the environment and subsequently contaminate the food chain. It is therefore essential to monitor heavy metals content in the soil, so as to prevent too much accumulation in human beings and animals through food chain. Test soil samples were collected from Nigeria Ports Authority (NPA) expressway open dump, and background (control) soil samples were also collected at about 2 km from the open dump and spatial test samples were also collected. The physicochemical properties of the soil were determined. Tessier’s sequential extraction protocols were used to assess the geochemical forms of Cr, Pb, Zn, and Mn in the soil of the open dump. The concentrations of the heavy metals in the extracts were determined in a pre-calibrated atomic absorption spectrophotometer and they are above the background sample values. The metal assessment index (Igeo) evaluated, indicated that the soil in the vicinity of the open dump was highly polluted. The results obtained showed the mobile metal pools which are available to plants roots.

关键词： Contamination Risk Assessment Soil Heavy Metals Dump

Sequential extraction and Mobility Factor of Metals in the Urban Soil of Warri-Nigeria (A Case Study of the environment of esisi Open Dump)

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Journal of environmental Protection 2021年第3期12卷 196-208页

作者： helen Ataikiru I. e. Okieimen College of education Warri Nigeria Department of Chemistry University of Benin Benin Nigeria

Sequential fractionation of Cr, Zn, Pb and Mn in soil samples collected 5 m - 104 m away from esisi open dump was determined to evaluate the potential health danger posed by the metals. Spatial test soil samples were collected at various increasing distances (5 m - 104 m) from the epicentre of the dump using a stainless steel auger. Tessier’s sequential extraction protocols were employed. The concentrations of the metals in the various fractions were determined, the fractions are exchangeable fraction, carbonate fraction, Fe-Mn oxide fraction, organic fraction and residual fraction. The metals were found mostly concentrated in the Fe-Mn oxide fraction. This study has provided information on the mobility factors and chemical forms of Cr, Zn, Pb and Mn in the soil of the environment of esisi open dump and the environmental risk of the metals in the environment of esisi open dump.

关键词： environment Open Dump Health Risk Fraction Mobility

SCI citation analysis and impact factor prediction of JZUS-A in 2008

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Journal of Zhejiang University-Science A(Applied Physics & engineering) 2009年第1期10卷 149-150页

作者： Zi-yang ZHAI Xiu-fang WU Yue-hong (helen) ZHANG editors Journals of Zhejiang University SCIENCE (A &B) Zhejiang University Press Hangzhou 310027 China

Journal of Zhejiang University-SCIeNCe A(JZUS-A),its former version named Journal of Zhejiang University-SCIeNCe(ISSN 1009-3095),has been covered by Science Citation Index expanded(SCI-e)since *** now,all the 500 pape... 详细信息

关键词：期刊编辑出版《浙江大学学报》

Favorable response to subcutaneous administration of infliximab in rats with experimental colitis

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World Journal of Gastroenterology 2005年第43期11卷 6843-6847页

作者： John K Triantafillidis Apostolos e Papalois Aikaterini Parasi emmanuel Anagnostakis Stavros Burnazos Aristofanis Gikas emmanuel G Merikas emmanuel Douzinas Maria Karagianni helen Sotiriou Department of Gastroenterology experimental Research Unit Department of Pathology

AIM： To investigate the influence of infliximab （Remicade） on experimental colitis produced by 2,4,6,trinitrobenzene sulfonic add （TNBS） in rats. MeTHODS： Thirty-six Wistar rats were allocated into four groups （three groups of six animals each and a fourth of 12 animals）. Six more healthy animals served as normal controls （Group 5）. Group 1： colitis was induced by intracolonic installation of 25 mg of TNBS dissolved in 0.25 mL of 50% ethanol and infliximab was subcutaneously administered at a dose of 5 mg/kg BW; Group 2： colitis was induced and infliximab was subcutaneously administered at a dose of 10 mg/kg BW; Group 3： colitis was induced and infliximab was subcutaneously administered at a dose of 15 mg/kg BW; Group 4： colitis was induced without treatment with infliximab. Infliximab was administered on d 2-6. On the 7^th d, all animals were killed. The colon was fixed in 10% buffered formalin and examined by light microscopy for the presence and activity of colitis and the extent of tissue damage. Tumor necrosis factor-alpha （TNF-α） and malondialdehyde （MDA） were also measured. ReSULTS： Significant differences concerning the presence of reparable lesions and the extent of bowel mucosa without active inflammation in all groups of animals treated with infliximab compared with controls were found. Significant reduction of the tissue levels of TNF-α in all groups of treated animals as compared with the untreated ones was found （0.47＋0.44, 1.09＋0.86, 0.43＋0.31 vs 18.73＋10.53 respectively）. Significant reduction in the tissue levels of MDA was noticed in group 1 as compared to group 4, as well as between groups 2 and 4. CONCLUSION： Subcutaneous administration of infliximab reduces the inflammatory activity as well as tissue TNF-α and MDA levels in chemical colitis in rats. Infliximab at a dose of 5 mg/kg BW achieves better histological results and produces higher reduction of the levels of TNF-α than at a dose of 10 mg/kg BW. Infliximab at a dose of 5 mg/kg BW produces

关键词： experimental colitis Infliximab Inflammatorybowel disease Tumor necrosis factor-alpha Malondialdehyde Ulcerative colitis

Microwave-assisted catalyst-free hydrolysis of fibrous cellulose for deriving sugars and biochemicals

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Frontiers of Chemical Science and engineering 2019年第4期13卷 718-726页

作者： Songshan Jiang helen Daly Huan Xiang Ying Yan Huiping Zhang Christopher Hardacre Xiaolei Fan School of Chemical engineering and Analytical Science The University of ManchesterManchester M139PLUK School of Chemistry and Chemical engineering Chongqing University of Science and TechnologyChongqing 401331China School of Chemistry and Chemical engineering South China University of TechnologyGuangzhou 510640China

Microwave(MW)assisted catalyst-free hydrolysis of fibrous cellulose(FC,cellulolysis)at 200℃promoted a cellulose conversion o f ca.37.2%and quantitative production o f valuable C5/C6 sugars(e.g.,glucose)and the according platform biochemicals(e.g.,5-hydroxymethylfurfliral),corresponding to an overall selectivity o f 96.5%.Conversely,conventional hydrothermal cellulolysis under similar conditions was not effective,even after 24 h,carbonising the *** on the systematic study of MW-assisted cellulolysis,the specific interaction between water molecules and macroscopic FC under the MW irradiation was proposed,accounting for the interpretation o f the experimental *** kinetic energy o f water molecules under the MW irradiation facilitated the C-C(in the non-hindered surface-CH2OH groups)and C-O-C bond breaking(inside the cellulose cavities)in FC,producing primary cellulolysis products of xylose,glucose and cellobiose.

关键词： microwave fibrous cellulose hydrolysis sugars mechanism

Magneto-elastic Coupling in a Sinusoidal Modulated Magnet Cr_(2)GaN

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Chinese Physics Letters 2022年第9期39卷 72-75页

作者： Hui-Can Mao Yu-Feng Li Qing-Yong Ren Mi-Hai Chu helen e.Maynard-Casely Franz Demmel Devashibhai Adroja Hai-Hu Wen Yin-Guo Xiao Hui-Qian Luo Beijing National Laboratory for Condensed Matter Physics Institute of PhysicsChinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China National Laboratory of Solid State Microstructures and Department of Physics Collaborative Innovation Center of Advanced MicrostructuresNanjing UniversityNanjing 210093China Institute of High energy Physics Chinese Academy of SciencesBeijing 100049China Spallation Neutron Source Science Center Dongguan 523803China School of Advanced Materials Shenzhen Graduate SchoolPeking UniversityShenzhen 518055China Australian Centre for Neutron Scattering Australian Nuclear Science and Technology OrganisationLucas Heights NSW-2232Australia ISIS Facility Rutherford Appleton LaboratoryChiltonDidcot Oxon OX110QXUnited Kingdom Songshan Lake Materials Laboratory Dongguan 523808China

We use neutron powder diffraction to investigate the magnetic and crystalline structure of Cr_(2)GaN.A magnetic phase transition is identified at T≈170 K,whereas no trace of structural transition is observed down to 6 *** Rietveld refinement with irreducible representations,the spin configuration of Cr ions in Cr_(2)GaN is depicted as an incommensurate sinusoidal modulated structure characterized by a propagating vector k=(0.365,0.365,0).Upon warming up to the paramagnetic state,the magnetic order parameter closely resembles to the temperature dependence of c-axis lattice parameter,suggesting strong magneto-elastic coupling in this ***,Cr_(2)Ga N provides a potential platform for exploration of magnetically tuned properties such as magnetoelectric,magnetostrictive and magnetocaloric effects,as well as their applications.

关键词： magnetic elastic Coupling

Biodegradable stent or balloon dilatation for benign oesophageal stricture: Pilot randomised controlled trial

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World Journal of Gastroenterology 2014年第48期20卷 18199-18206页

作者： Anjan Dhar helen Close Yirupaiahgari K Viswanath Colin J Rees helen C Hancock A Deepak Dwarakanath Rebecca H Maier Douglas Wilson James M Mason Department of Gastroenterology County Durhamand Darlington NHS Foundation Trust Co. Durham DL14 6ADUnited Kingdom Durham Clinical Trials Unit School of Medicine Pharmacy and Health Durham University Queen’s Campus Wolfson Research Institute University Boulevard Stockton-on-Tees TS17 6BH United Kingdom Department of Surgery James Cook University Hospital Marton Road Middlesbrough TS4 3BW United Kingdom Department of Gastroenterology South Tyneside Hospitals NHS Foundation Trust Harton Lane South Shields NE34 0PL United Kingdom Department of Gastroenterology University Hospitals of North Tees Hardwick Stockton on Tees TS19 8PE United Kingdom

AIM: To undertake a randomised pilot study comparing biodegradable stents and endoscopic dilatation in patients with strictures.

关键词： Benign oesophageal stricture Biodegradable stent endoscopic balloon dilatation Pilot study Randomised controlled trial Dysphagia

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Hybrid solar cells based on poly（3-hexylthiophene） and electrospun TiO2 nanofibers modified with CdS nanoparticles

作者： (新西兰)海伦·布朗(helen brown)

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Progress in Natural Science:Materials International 2013年第5期23卷 514-518页

作者： Shingchung Lo Zhike Liu Jinhua Li helen Laiwa Chan Feng Yan Department of Applied Physics and Materials Research Centre The Hong Kong Polytechnic University

Organic–inorganic hybrid solar cells based on poly(3-hexylthiophene) and electrospun TiO2 nano bers were fabricated by solution *** ef ciency of the device was improved by modifying CdS nanoparticles on the surface of TiO2 by electrochemical *** CdS layer can lead to the increase of both open circuit voltage and short circuit current of the device,which are attributed to enhanced exciton dissociation and light absorption and suppressed carrier recombination by CdS at the ***,too thick CdS layer led to increased series resistance and decreased ef ciency of the ***,the optimum condition of the CdS deposition was obtained,which increased the power conversion ef ciency of the device for about 50%.Our results indicate that the surface modi cation on the inorganic semiconductor layer is an effect way to improve the performance of the hybrid solar cells.

关键词： Organic solar cells TiO2 nanofiber CdS nanoparticle Surface modification

Magnetoelectric and converse magnetoelectric responses in Tb_xDy_(1-x)Fe_(2-y) alloy & Pb(Mg_(1/3)Nb_(2/3))_(1-x)Ti_xO_3 crystal laminated composites

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Chinese Science Bulletin 2008年第14期53卷 2129-2134页

作者： JIA YanMin LUO HaoSu OR Siu Wing WANG YaoJin CHAN helen L W State Key Laboratory of High Performance Ceramics and Superfine Microstructure Shanghai Institute of Ceramics Chinese Academy of Sciences Shanghai 201800 China Department of Applied Physics The Hong Kong Polytechnic University Hong Kong China

Measured results of magnetoelectric (Me) and converse magnetoelectric (CMe) effects of TbxDy1-xFe2-y/ Pb(Mg1/3Nb2/3)(1-x)TixO3/TbxDy1-xFe2-y (TD/PMNT/TD) and PMNT/TD/PMNT laminated composites are pre- sented. Me effect was determined by measuring laminate voltage output under a Helmholtz-gener- ated AC field biased by a DC field (0―1 kOe) (1 Oe = 79.58 A/m). The CMe effect was measured by re- cording the voltage induced in a solenoid encompassing the Me sample while exposed to a DC bias field and PMNT layer driven by a 10 V AC source. The Me and CMe responses in the two laminated structure are linear. The highest values of Me coefficients in TD/PMNT/TD and PMNT/TD/PMNT com- posites are 384 mV/Oe and 158 mV/Oe, respectively, while the highest values of CMe coefficients in the two composites are 118 mG/V and 162 mG/V (1 G=10-4 T), respectively.

关键词：磁电效应压电性复合材料合金晶体结构