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Chinese Journal of Polymer Science 2016年第6期34卷 730-738页

作者： ji-jie wen 吕宏光 de-e liu 高辉 School of Chemistry and Chemical engineering Tianjin Key Laboratory of Organic Solar Cells and Photochemical ConversionTianjin University of TechnologyTianjin 300384China

A series of β-cyclodextrin-conjugated 4-arm poly（ethylene glycol）-poly（lactide-co-glycolide）（4-arm PeG-PLGA） copolymers were synthesized by a ring-opening polymerization of D,L-lactide and glycolide using 4-arm PeG as initiator, and then conjugated with mono（6-ethylenediamine-6-deoxy）- β-cyclodextrin （CDen） or ethylenediamino-bridged bis- β-CD （BCDen）. The chemical structures of copolymers were confirmed by IH-NMR and FTIR spectroscopy. The , β-CD-conjugated PeG-PLGA formed stable reverse micelles due to the formation of fl-CD and bovine serum albumin （BSA） inclusion complexation, which could accommodate BSA in the organic solvent with improved encapsulation efficiency. Moreover, we demonstrated a one-step approach to construct macroporous protein-containing films using these reverse micelles. The films with ordered pore arrays were directly prepared from reverse micelles. Interestingly, the protein was totally located in the whole matrix except for the pores.

关键词： β-Cyclodextrin Copolymer Reverse micelles Ordered porous structures Proteins.

Optical bistability and multistability in a defect slab doped by GaAs/AlGaAs multiple quantum wells

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Chinese Physics B 2016年第5期25卷 223-228页

作者： Seyyed Hossein Asadpour G Solookinejad M Panahi e Ahmadi Sangachin Department of Physics Marvdasht Branch Islamic Azad University

We proposed a new model for controlling the optical bistability（OB） and optical multistability（OM） in a defect slab doped with four-level GaAs/AlGaAs multiple quantum wells with 15 periods of 17.5 nm GaAs wells and 15-nm Al_（0.3）Ga_（0.7）As barriers. The effects of biexciton energy renormalization, exciton spin relaxation, and thickness of the slab on the OB and OM properties of the defect slab were theoretically investigated. We found that the transition from OB to OM or vice versa is possible by adjusting the controllable parameters in a lab. Moreover, the transmission, reflection, and absorption properties of the weak probe light through the slab were also discussed in detail.

关键词： optical bistability optical multistability quantum well nanostructure

Petroleum hydrocarbon concentrations in eight mollusc species along Tamilnadu coast, Bay of Bengal, India

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Journal of environmental Sciences 2011年第7期23卷 1129-1134页

作者： S. veerasingam R. venkatachalapathy S. Sudhakar P. Raja v. Rajeswari Department of Physics Annamalai University Centre of Advanced Study in Marine Biology Faculty of Marine Sciences Annamalai University

eight mollusc species and sediment samples collected from three different stations along Tamilnadu coast, Bay of Bengal, India were analysed for the levels of petroleum hydrocarbons to elucidate the status of the petroleum residues in mollusc meant for human consumption. The concentrations of petroleum hydrocarbons in sediments along Tamilnadu coast varied from 5.04–25.5 μg/g dw （dry weight）. High concentration of petroleum hydrocarbons in the sediment of Uppanar estuary （25.5 ± 1.45 μg/g dw） was perhaps land and marine based anthropogenic sources of this region. The petroleum hydrocarbon residues in eight mollusc species collected from Uppanar, vellar and Coleroon estuaries varied between 2.44–6.04 μg/g ww （wet weight）. Although the concentration of petroleum hydrocarbons in sediment of the Uppanar region was markedly higher than the background, the petroleum hydrocarbon residues in mollusc collected from Uppanar estuary did not suggest bioaccumulation. The results signified that industrial growth has affected the aquatic environments and regular monitoring will help to adopt stringent pollution control measures for better management of the aquatic region.

关键词： petroleum hydrocarbons sediment mollusc pollution Tamilnadu coast

Tectonometamorphic Cycles in Different Geodynamic Conditions

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Journal of earth Science 2000年第4期19卷 11-19页

作者： Miller Yu v Dufour MS Institute of Precambrian Geology and Geochronology Russian Academy of ScienceSt-Petersburg 199034Russia Geological Faculty St-Petersburg State University St-Petersburg 199034Russia

Formation and attenuation of crust thermal anomalies, accompanied by development of geological structures, are governed by special laws, together with metamorphism and other endogenic process, form tectonometamorphic cycle (TMC). Because of rock rheology under metamorphic conditions, the structures, concurring with metamorphism, reflect geodynamic conditions much more perfect than those of the structures of nonmetamorphosed rocks. For this reason, structural investigations open wide, sometimes unique, possibilities for geodynamic research into regional metamorphosed terrains. The TMC features under different geodynamic conditions are shown with examples of California (subduction), Himalaya and Junggar Alatau (collision), and Northwest environs of the White Sea (polycyclic development). The analysis of these units serves as basis of some general conclusions. TMC, the steady pattern of crust thermal anomalies manifestation, does not practically depend on peculiarities of metamorphism. At lower and middle crust levels, occur the high-temperature complete cycles that include following two stages. The first is represented by nappes and paragenes of parallel bedding flow, the second, by linear folds, domes and faults. At top levels of fold complexes display the low-temperature reduced cycles, expressed only by structures of the second stage. There are gradual transitions between the complete and reduced cycles. Thermal anomalies in the first stage of complete cycles devolop against the background of large horizontal displacements at contacts between interacting plates or are genetically connected with their gently sloping fault planes. Of all structural elements of the cycles, in compressional environments (nappes, linear folds, domes etc.), only the structures of the first stage of complete cycles can be considered as indications of plate tectonics. Presence of such structures at the most ancient supracrustal complexes point to existence of plate tectonics already at

关键词： complete and reduced tectonometamorphic cycles nappe parallel bedding flow schistosity linear fold dome.

Physicochemical aspects of allanite flotation

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Journal of Rare earths 2014年第5期32卷 476-486页

作者： Adam Jordens Chris Marion Olga Kuzmina Kristian e.Waters Department of Mining and Materials engineering McGill University

This paper investigated the physicochemical properties of allanite, a Re-silicate, by measuring zeta potential in the absence and presence of three different flotation collectors （benzohydroxamic acid, sodium oleate and dodecylamine）. This data was then verified by microflotation experiments and with bubble-particle attachment pictures. The investigated properties of allanite were com- pared to those of quartz, a common gangue mineral in many Re deposits. The results of this work indicated that only dodecylamine was able to achieve a selective separation of allanite and quartz. This was accomplished by lowering the dodecylamine dosage so that only quartz was recovered by microflotation.

关键词： allanite flotation surface chemistry zeta potential bubble-particle attachment rare earths

Kinetic analysis via mathematical modeling for ferrous iron oxidation in a class of SBR-type system

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Chinese Journal of Chemical engineering 2019年第10期27卷 2472-2480页

作者： edgar NTec-Caamal Refugio Rodríguez-vázquez Luis GTorres-Bustillos Ricardo Aguilar-López Center for Research and Advanced Studies of the National Polytechnic Institute Av.Instituto Politécnico Nacional No.2508Colonia San Pedro ZacatencoC.P.07360 Ciudad de México D.F.Mexico Interdisciplinary Professional Unit of Biotechnology-National Polytechnic Institute(UPIBI-IPN) Acueducto s/nLa Laguna TicománGustavo A.Madero07340Ciudad de MéxicoMexico

This paper analyses the oxidation of ferrous iron via chemical and biological means in a class of Sequential Batch Reactors(SBR-type).For this,a kinetic model for the study of iron oxidation system is proposed,followed by a parametric sensitivity analysis and a bifurcation analysis,which allow selecting the most influential kinetic parameters in order to ensure a suitable prediction capacity of the mathematical *** system consists of two SBR bioreactors,the first being used to produce hydrogen peroxide(H2O2)that is fed to a second reactor where the iron oxidation is carried out by chemical–biological *** predictions were compared with experimental data for the production of H2O2 and for ferrous iron oxidation,finding suitable correlation coefficients(r2 N 0.98)for each state *** bifurcation analysis showed the trajectories of the main variables,such as,biomass,H2O2 and ferrous iron,under the change of the most influential kinetic *** analysis demonstrates the usefulness of the constructed model to predict the kinetic behaviour of the SBR-type process.

关键词： Bifurcation analysis Hydrogen peroxide Iron oxidation Modeling Simulation

Pituitary Apoplexy: A MRI Finding Case and Literature Review

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Open Journal of Radiology 2018年第1期8卷 13-21页

作者： e. v. Acko-Ohui I. Garba A. Setchéou U. v. Acko A. Konan P. Yapo Department of Radiodiagnosis and Medical Imaging University Hospital (UH) of Treichville Abidjan C&#244 te d’Ivoire Department of Radiodiagnosis and Medical Imaging University Hospital (UH) of Yopougon Abidjan C&#244 te d’Ivoire Department of Internal Medicine and Geriatrics University Hospital (UH) of Treichville Abidjan C&#244 te d’Ivoire

Introduction: Pituitary apoplexy is an ischemic or hemorrhagic rearrangement within a pituitary adenoma. Pituitary apoplexy is a rare disease that constitutes a diagnosis and therapeutic emergency. Most of the time, apoplexy is the manifestation inaugural of an adenoma unknown, but it can also complicate a known adenoma. All adenomas can be concerned with the occurrence of apoplexy, with an equivalent risk, whether they are secreting or not and whatever the type of secretion. We report the case of a patient in whom the cranio-encephalic MRI enabled to make the diagnosis. Observation: A 57-years-old woman abruptly presented severe cephalodynia, followed by a left visual field defect. The clinical examination revealed an alteration of the consciousness to the type of obstruction and a decrease in left visual acuity is 4/10th. The cranio-encephalic MRI performed revealed an expansive intrasellar process with suprasellar extension of heterogeneous signal on all the sequences performed alternating hemorrhagic stigmata in the central tumor zone suggesting a macroadenoma having bled, compatible with pituitary apoplexy. She received medical treatment and hormonotherapy, followed by surgical excision. The outcome was satisfactory. Conclusion: Pituitary apoplexy is a rare but serious complication of pituitary adenomas. It is responsible for various neuro-ophthalmologic. Pituitary apoplexy involves the patient’s functional and vital prognosis due to acute panhypopituitarism. It is a diagnostic and therapeutic emergency. MRI is a major contribution to diagnosis. Treatment is based on the combination of hormone replacement therapy and trans-sphenoidal tumor excision.

关键词： Hypophysis Cerebrovascular Apoplexy Cranio-encephalic MRI Cephalodynia Pituitary Adenoma

Dietary inclusion of multispecies probiotics to reduce the severity of post-weaning diarrhea caused by escherichia coli F18+ in pigs

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Animal Nutrition 2021年第2期7卷 326-333页

作者： Yawang Sun Marcos e.Duarte Sung Woo Kim Department of Animal Science North Carolina State UniversityRaleighNC27695United States

This study was aimed to determine the efficacy of multispecies probiotics in reducing the severity of post-weaning diarrhea caused by enterotoxigenic escherichia coli(eTeC)F18+on newly weaned ***-two pigs(16 barrows and 16 gilts,BW=6.99±0.33 kg)at 21 d of age were individually allotted in a randomized complete block design with 2×2 factorial arrangement of *** were selected from sows not infected previously and not vaccinated against *** were fed experimental diets for 25 d based on 10 d phase 1 and 15 d phase *** factors were eTeC challenge(oral inoculation of saline solution or *** F18+at 2×109 CFU)and probiotics(none or multispecies probiotics 0.15%and 0.10%for phase 1 and 2,respectively).Body weight and feed intake were measured on d 5,9,13,19,and *** scores were measured *** samples were taken on d 19 and *** d 25,all pigs were euthanized to obtain samples of digesta,intestinal tissues,and *** tumor necrosis factor alpha(TNFα),malondialdehyde(MDA),peptide YY(PYY),and neuropeptide Y(NPY)were measured in serum and intestinal *** were analyzed using the MIXeD procedure of *** fecal score of pigs was increased(PeTeC challenge at the post-challenge *** eTeC challenge decreased(Pejunal villus height and crypt depth,tended to increase(P=0.056)jejunal TNFα,increased(Peal crypt depth,and decreased(Perum *** probiotics decreased(Perum TNFα,tended to reduce(P=0.064)jejunal MDA,tended to increase(P=0.092)serum PYY,and increased(Pejunal villus height,and especially villus height-to-crypt depth ratio in challenged *** performance of pigs were not affected by eTeC challenge,whereas the probiotics increased(Pended to increase(P-0.069)G:F *** conclusion,eTeC F18+challenge caused diarrhea,intestinal inflammation and morphological damages without affecting the growth *** multispecies probiotics enhanced growth pe

关键词： escherichia coli Growth performance Gut health Nursery pig Post-weaning diarrhea Probiotic

Polyethoxylation and polypropoxylation reactions：Kinetics,mass transfer and industrial reactor design

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Chinese Journal of Chemical engineering 2018年第6期26卷 1235-1251页

作者： e.Santacesaria R.Tesser M.Di Serio eurochem engineering srl. Via Codogno 5 IT-20139 Milan Italy University of Naples 'Federico II' Department of Chemical Sciences Via Cinthia IT-80126 Naples Italy

ethoxylation and propoxylation reactions are performed in the industry to produce mainly non-ionic surfactants and ethylene oxide(eO)–propylene oxide(PO) *** the reactions occur in gas–liquid reactors by feeding gaseous eO,PO or both into the reactor containing a solution of an alkaline catalyst(KOH or Na OH).Non-ionic surfactants are produced by using liquid starters like fatty alcohols,fatty acids or alkyl-phenols,while when the scope is to prepare eO–PO copolymers the starter can be a mono-or multi-functional alcohol of low molecular *** reactions are strongly exothermic,and eO and PO,in some conditions,can give place to runaway and also to explosive side ***,the choice of a suitable reactor is a key factor for operating in safe conditions.A correct reactor design requires:(i) the knowledge of the kinetic laws governing the rates of the occurring reactions;(ii) the role of mass and heat transfer in affecting the reaction rate;(iii) the solubility of eO and PO in the reacting mixture with the non-ideality of the reacting solutions considered;(iv) the density of the reacting *** these aspects have been studied by our research group for different starters of industrial interest,and the data collected by using semibatch well stirred laboratory reactors have been employed for the simulation of industrial reactors,in particular Gas–Liquid Spray Tower Loop Reactors.

关键词： ethoxylation Propoxylation Kinetics Mass transfer Spray tower loop reactor

Proterozoic Dyke Swarms of the Siberian Craton and Their Geodynamic Implications

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Acta Geologica Sinica(english edition) 2016年第S1期90卷 6-7页

作者： Dmitry P.GLADKOCHUB Tatiana v.DONSKAYA Richard e.eRNST Sergei A.PISARevSKY Michael T.D.WINGATe Ulf SODeRLUND Institute of the earth’s Crust Siberian Branch of the Russian Academy of Sciences Department of earth Sciences Carleton University Faculty of Geology and Geography Tomsk State University Australian Research Council Centre of excellence for Core to Crust Fluid Systems(CCFS)and the Institute for Geoscience Research(TIGe R) Department of Applied GeologyCurtin University School of earth and environment University of Western Australia Geological Survey of Western Australia GeoB iosphere Science Centre Department of GeologyUniversity of Lund

We present a summary of late Paleoproterozoic to Neoproterozoic mafic magmatism in the Siberian craton which allows us distinguish following main pulses of mafic dyke emplacement:1)1860–1850 Ma mafic dykes are locali... 详细信息

关键词： Proterozoic Dyke Swarms of the Siberian Craton and Their Geodynamic Implications