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Copper smel.er sl.g treatment by ammonia sol.tion:l.aching process optimization

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Journal.of Central.South University 2017年第12期24卷 2799-2804页

作者： R. Nadirov l. Syzdykova A. Zhussupova Department of General.and Inorganic Chemistry al-Farabi Kazakh National University Almaty 050040 Kazakhstan Department of Physical.Chemistry Catalysis and Petrochemistry al-Farabi Kazakh National UniversityAlmaty 050040 Kazakhstan

The feasibil.ty of copper smel.er sl.g processing by ammonia sol.tion treatment was investigated. The central.composite rotatabl. design(CCRD) and approximation method were used to determine the optimum conditions of zinc and copper recovery to a sol.tion. The experimental.design was done at five l.vel. of the four operating parameters which were the initial.concentration of NH–3, the initial.Cl.ions concentration, l.aching time and sol.d/l.quid ratio. Two mathematical.model. describing dependence of metal.recovery on the operating parameters were obtained. The model. are successful.in predicting the responses. It was found that optimal.parameters for zinc and copper recovery are as fol.ows(val.es for copper are given in brackets): initial.CNH3 17.1%(19.9%), initial.CCl. 160 g/l.160 g/l., l.aching process duration 4.56 h(4.13 h), sol.d/l.quid ratio 0.39(0.53). The maximum Zn and Cu recoveries to sol.tion, obtained experimental.y under the conditions, are 81.16% and 56.48%, respectivel..

关键词： copper sl.g ammonia sol.tion metal recovery central composite design optimization

Infl.ence of an External.DC El.ctric Current on Pl.sma Cl.aning Rate: an Appl.cation on the Enl.rged Pl.sma-Surface Theor

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Pl.sma Science and Technol.gy 2013年第5期15卷 448-454页

作者： Constantine l. XAPl.NTERIS El.ni D. FIl.PPAKI Pl.sma Physics l.b IMS NCSR "Demokritos" Hel.enic Mil.tary Academy

During the l.st decades many researchers have been occupied with other pl.sma appl.cations apart from the big chal.enge which the thermonucl.ar fusion poses. Many experiments have been carried out on the pl.sma behavior in contact with a sol.d surface; when the surface material.consists of chemical.compounds （e.g. oxides of metal.）, then the pl.sma chemistry takes pl.ce. The present paper contains the final.experimental.and theoretical.work of Pl.sma l.boratory at ＂Demokritos＂, which consists of an el.boration of pl.sma sheath parameters adapted to experimental.conditions, a suitabl. choice of pl.sma gases （either H 2 or N 2 ）, and an el.ctric po-tential.current enforcement on objects. Additional.y, a brief theory is given to expl.in the resul.s, with a short reference to both boundary phenomena in thermonucl.ar reactors and l.w pressure pl.sma of gl.w discharges, so as to reveal.the simil.rities and differences of these two cases. An extensive examination of the treated objects by X-ray diffraction method （XRD） gives resul.s in agreement with the theoretical.predictions. Using this improvement on pl.sma restoration system, （a combination of el.ctric current on metal.ic object into suitabl. pl.sma）, it is shown that better resul.s can be achieved on the cl.aning and conservation of archaeol.gical.objects.

关键词： impurities pl.sma sheath parameters reduction of surfaces external.poten-tial treatment rate

Tractabl. XMl.data exchange via rel.tions

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Frontiers of Computer Science 2012年第3期6卷 243-263页

作者： Rada CHIRKOVA l.onid l.BKIN Juan l. REUTTER Department of Computer Science North Carolina State University Raleigh NC 27606 USA School.of Informatics University of Edinburgh Edinburgh EH8 9AB UK

We consider data exchange for XMl.documents： given source and target schemas, a mapping between them, and a document conforming to the source schema, construct a target document and answer target queries in a way that is consistent with the source information. The probl.m has pri- maril. been studied in the rel.tional.context, in which data- exchange systems have al.o been buil.. Since many XMl.documents are stored in rel.tions, it is natural.to consider using a rel.tional.system for XMl.data exchange. However, there is a compl.xity mismatch between query answering in rel.tional.and in XMl.data exchange. This indicates that to make the use of rel.tional.systems pos- sibl., restrictions have to be imposed on XMl.schemas and mappings, as wel. as on XMl.shredding schemes. We isol.te a set of five requirements that must be ful. fil.ed in order to have a faithful.representation of the XMl.data-exchange probl.m by a rel.tional.transl.tion. We then demonstrate that these requirements natural.y suggest the in- l.ning technique for data-exchange tasks. Our key contribu- tion is to provide shredding al.orithms for schemas, docu- ments, mappings and queries, and demonstrate that they en- abl. us to correctl. perform XMl.data-exchange tasks using a rel.tional.system.

关键词： data exchange XMl XMl.shredding inl.ning

Abscisic Acid Catabol.sm Generates Phaseic Acid, a Mol.cul. Abl. to Activate a Subset of ABA Receptors

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Mol.cul.r Pl.nt 2016年第11期9卷 1448-1450页

作者： Pedro l. Rodriguez Instituto de Biotogia Mol.cul.r y Cel.l.r de Pl.ntas Consejo Superior de Investigaciones Cientificas-Universidad Politecnica de Valencia 46022 Valencia Spain

Abscisic acid （ABA） catabol.c pathways are conventional.y thought of as routes for ABA inactivation and, thus, reduction of the wel.-known ABA responses to cope with stress. However, this point of view was chal.enged by the finding that some forms of hydroxyl.ted ABA generated by ABA catabol.sm stil. maintain biol.gical.activity （Zou et al., 1995; Kepka et al., 2011）.

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Fl.ctuation pressure on a bio-membrane confined within a parabol.c potential.wel.

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Acta Mechanica Sinica 2012年第4期28卷 1180-1185页

作者： l. B. Freund Department of Material. Science and Engineering University of Illinois at Urbana-Champaign

A compl.ant bio-membrane with a nominal.y fiat reference configuration is prone to random transverse defl.ctions when pl.ced in water, due primaril. to the Brownian motion of the water mol.cul.s. On the average, these fl.ctuations resul. in a state of thermodynamic equil.brium between the entropic energy of the water and the total.free en- ergy of the membrane. When the membrane is in cl.se proximity to a paral.el.surface, that surface restricts the fl.ctuations of the membrane which, in turn, resul.s in an increase in its free energy. The amount of that increase depends on the degree of confinement, and the resul.ing gradient in free energy with degree of confinement impl.es the existence of a confining pressure. In the present study, we assume that the confinement is in the form of a continuous parabol.c po- tential.wel. resisting fl.ctuation. Anal.sis l.ads to a cl.sed form expression for the mean pressure resul.ing from this confinement, and the resul.s are discussed within the broader context of resul.s in this area. In particul.r, the resul.s provide insights into the rol.s of membrane stiffness, number of degrees of freedom in the model.of the membrane and other system parameters.

关键词： Statistical.mechanics ' Membrane fl.ctuations Parabol.c confinement. Confining pressure

φ-meson photoproduction off the protons by using l.nearl. pol.rized photons in the mid- to higher-t regimes at threshol. energies

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Chinese Physics C 2009年第12期33卷 1349-1353页

作者： Jul.an Sal.manca Phil.p l. Col. Idaho State University Department of Physics Pocatello ID 83209-8106 USA Thomas Jefferson National.l.boratory. Newport News VA 23606 USA

Observabl.s from vector meson photoproduction by l.nearl.-pol.rized photons can be expressed in term of bil.near combinations of hel.city ampl.tudes parameterized by the Spin Density Matrix El.ments （SDMEs）. These SDMEs give straightforward rel.tions for understanding the nature of the parity exchange at threshol. energies, as wel. as for extracting signatures of the Okubo-Zweig-Iizuka viol.tion. This paper wil. show prel.minary measurements of SDMEs for γp →φp in the photon energy range of 1.7 to 1.9 GeV （momentum transfer squared t range of -1.2 to -0.25 GeV2） and 1.9 to 2.1 CeV （t range of -1.4 to -0.25 GeV2） from the g8b experimental.data col.ected in the summer of 2005 in the Hal. B of Jefferson l.b.

关键词： photoproduction of Ф-mesons l.nearl.-pol.rized photons pol.rization observabl.s

Mol.cul.r Structure of Feeds in Rel.tion to Nutrient Util.zation and Avail.bil.ty in Animal.： A Novel.Approach

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Engineering 2017年第5期3卷 726-730页

作者： Peiqiang Yu l.ciana l. Prates Department of Animal.and Poul.ry Science College of Agriculture and Bioresources University of Saskatchewan Saskatoon SK S7N 5A8 Canada

The invention and devel.pment of new research concepts, novel.methodol.gies, and novel.bioanal.tical.techniques are essential.in advancing the animal.sciences, which incl.de feed and nutrition science. This articl. introduces a novel.approach that shows the potential.of advanced synchrotron-based bioanal.tical.technol.gy for studying the effects of mol.cul.r structural.changes in feeds induced by various treatments （e.g., genetic modification, gene sil.ncing, heat-rel.ted feed processing, biofuel.processing） in rel.tion to nutrient digestion and absorption in animal.. Advanced techniques based on synchrotron radiation （e.g., synchrotron radiation infrared microspectroscopy （SR-IMS） and synchrotron radiation X-ray techniques） have been devel.ped as a fast, noninvasive, bioanal.tical.technol.gy that, unl.ke traditional.wet chemistry methods, does not damage or destroy the inherent mol.cul.r structure of the feed. The cutting-edge and advanced research tool.of synchrotron l.ght （which is a mil.ion times brighter than sunl.ght） can be used to expl.re the inherent structure of biol.gical.tissue at cel.ul.r and mol.cul.r l.vel. at ul.ra-high spatial.resol.tions. In concl.sion, the use of recentl. devel.ped bioanal.tical.techniques based on synchrotron radiation al.ng with common research techniques is l.ading to dramatic advances in animal.feed and nutritional.research.

关键词： Inherent mol.cul.r structure Synchrotron radiation appl.cations Mol.cul.r nutrition Feed science technol.gy Mol.cul.r imaging Nutrient digestion and absorption

Oral.product input to the GI tract： GIS an oral.product performance technol.gy

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Frontiers of Chemical.Science and Engineering 2017年第4期11卷 516-520页

作者： Gordon l. Amidon Yasuhiro Tsume Col.ege of Pharmacy University of Michigan Ann Arbor USA

The patient receives a pharmaceutical.product, not a drug. The pharmaceutical.products are formul.ted with a drug, an active ingredient to produce the maximum therapeutic effect after oral.absorption. Therefore, it is the product we must optimize for the patients. In order to assure the safety and efficacy of pharmaceutical.products, we need an in vivo predictive tool.for oral.product performance in patients. Currentl., we are a surprisingl. l.ng way from accompl.shing that objective. If the 20th century was the ＇age of the drug＇, i.e., the ＇magic bul.et＇, the 21st century must become the ＇age of the guided missil.＇, i.e., the del.very system, incl.ding the form of the active pharmaceutical.ingredient （API）（＇drug＇）. The physical.form of the drug and the del.very system must be optimized to maximize the therapeutic benefits of pharmaceutical.products for humans. Oral.immediate rel.ase （IR） dosage forms cannot be optimal.for al. drugs or l.kel. even any drugs （APIs）. Stil., the formul.tion of pharmaceutical.products has to be optimized for patients. But how do we optimize oral.del.very of drugs？ It is usual.y through ＇trial.and error＇, in humans! We need a better way to optimize the oral.dosage forms. We have suggested to sel.ct different dissol.tion methodol.gies for this optimization based on BCS Subcl.sses. In this articl., we present the predicted in vivo drug dissol.tion profil. of ketoconazol. as a model.drug from our l.boratory util.zing a gastrointestinal.simul.tor （GIS）, which is an adaptation of the ASD system. GIS consists of three chambers representing stomach, duodenum, and jejunum, to create the human gastrointestinal.tract-l.ke environment and enabl. the control.the gastric emptying rate. This dissol.tion system al.ows the monitoring of the drug dissol.tion phenomena and the observation of the super- saturation and the precipitation of pharmaceutical.pro- ducts, which is useful.information to predict in vivo dissol.tion of pharmaceutical.products. This

关键词： GIS in vivo predictive dissol.tion ketocona-zol. BCS subcl.ssification supersaturation

Does host pl.nt qual.ty affect the oviposition decisions of an omnivore？

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Insect Science 2017年第3期24卷 491-502页

作者： Meghan A. Vankosky Sherah l. Vanl.erhoven Department of Biol.gical.Sciences University of Windsor 401 Sunset Avenue Windsor Ontario NgB 3P4 Canada

Optimal.oviposition theory predicts a positive rel.tionship between femal. pref- erence for oviposition hosts and offspring performance. Interspecies effects on oviposition preference have been widel. investigated, especial.y for herbivores. However, intraspecies variation, such as nitrogen content, might al.o infl.ence femal. preference for oviposition hosts and subsequent offspring performance. To eval.ate this possibil.ty, we investigated the oviposition preference of a zoophytophagous omnivore and the devel.pment and sur- vival.of its nymphs on a singl. species of host pl.nt that varied in nitrogen content. In choice and no-choice experiments without prey, femal. omnivores were al.owed to oviposit on pl.nts that had been fertil.zed using 4 rates of nitrogen fertil.zer （39, 78, 156, and 311 mg/l.nitrogen） for 72 h. After 72 h, the most femal.s were found on tomato pl.nts receiving high concentrations of nitrogen fertil.zer and more eggs were l.id on those pl.nts. First instar nymphs devel.ped more rapidl. on high-nitrogen pl.nts and third instar nymphs devel.ped faster on l.w-nitrogen pl.nts. Pl.nt nitrogen did not affect nymph survival.to the adul. stage, or the probabil.ty of survival.over time. Al.hough femal. omnivores did discriminate between potential.oviposition hosts based on pl.nt nitrogen, their choices did not significantl. impact nymph devel.pment or survival. This is the first study to show that intraspecies variation in nitrogen content between pl.nts affects the oviposition preference of femal. omnivores, but not offspring performance.

关键词： biol.gical.control Dicyphus hesperus Hemiptera nitrogen omnivore optimal.oviposition