Effect of Morphology of Instantaneous Inoculant on Inoculated Result of Melted Iron

In 192 2 ,AmericanMeehanappliedthefirstpatentforinoculatedcastiron .Nowtherearemorethan 10 0 0kindsofinoculantsintheworld .Thein oculationmeansthatsomematerialisputintomeltedirontocausesome physicalandchemicalchangeswhicharedifferentfromthosecausedbythealloyingelementinthecastiron .Intheearlydays ,themaincontentofinoculantwassilicon ,andsoonafterwardscalcium ,aluminium ,barium ,strontiumandmanga nese ,etcwereincluded .In 196 1,ceriumwasintro ducedintoinoculant .Nowtheinoculantsarewidelyappli…     

Computer Simulation of Effect of Intergrain Exchange Interaction on Magnetic Properties of Nanocomposite Magnets

Nanocompositemagnetsareoneofcandidatesformagnetsinthenextgeneration .Inananocompositemagnet,theexistenceofmagneticallysoftgrainswithahighsaturationmagnetizationenhancestherema nence,andconsequentlyahigh (BH ) max valueisachieved[1] .Asthemagnetizationinthesoftgrainsispreventedfromtheirreversalbytheintergrainex changeinteractionbetweensoftandhardgrains ,theintergrainexchangeinteractionplaysanimportantroleindeterminingmagneticproperties .Therefore ,itscontrolisconsideredtobeakeytechnologyforobt…     

The Characteristics of Adsorption and Desorption of Rare Earth Elements by the Main Types of Soils of China

The adsorption-desorption behavior of the mixed rare earth elements(RE)on the main types ofsoils of China,kaolinite and synthetic oxides was studied.The isothermal adsorption of RE was fitted toLangmuir.Freundlich and Temkin equations.The main factors determining the RE adsorption capacity ofthe soils are the type of clay mineral and the content of amorphous iron oxide in the soils.The above two fac-tors and the pH of soil determine the RE adsorption ability of the soils.The soil and synthetic iron,manga-nese oxides strongly adsorb RE specifically.     

Influence of Light Rare Earth on Toughness of Welded Seam of LAHS Steel

The influence mechanism of light rare earth elements, which are transited to the welding seam of low-alloy high strength (LAHS) steel through the covering of the electrode, on the toughness of the welding seam was studied. The experimental results show that proper amount of rare earth elements can desulfurate, dehydrogenate, reduce inclusions and purify the structure of the welding seam. Rare earth element additions have .the effect on welding seam and, at the same time, the transformation of side-batten ferrite is resisted while the pin-ferrite structure is promoted. The improvement of the toughness of the welding seam is due to the purifying action of rare earth elements as well as their refining effect on the structure. However, the toughness of the welding seam can decrease when the amount of light rare earth elements are added excessively because the crystal grains become coarser, porosities appear and the inclusions increase as well. The experimental results show that the suitable amount of light rare earth element additions is about 2%.     

of tend

on transplant are as follows: autologous tendon, allogeneic tendon, artificial tendon and tissue engineered tendon. Recently, studies on allogeneic tendon are more and more favorable. In late 1980s, establishment and development of tissue engineering bring a new way for repairing de     

Giant Magnetoimpedance Effect of As-Spun Nanocrystalline Ribbon of FeZrBCu Alloy

Now ,alotofkindsofmagneticsensorshavebeenwidelyusedinmanyfieldssuchascomputersandindustrialrobots .In 1992 ,MohriKetal[1] re portedthatthereisgiantmagneto inductanceinFe CoSiBamorphouswires .ACvoltageofthewireschangeswiththeexternalDCmagneticfieldsensi tively .WhentheACcurrentfrequencyisweak ,theskineffectisnotevident ,andthevariationofthevoltagemainlycomesfromtheinductanceeffect ,calledasgiantmagneto inductanceeffect .Within creasingACfrequency ,theskineffectbecomesstronger.Inthiscase ,…     

Standard Enthalpies of Formation of Solid Complexes of Lanthanide Nitrates with Alanine

Ｇｒｅａｔｉｎｔｅｒｅｓｔｈａｓｂｅｅｎａｒｏｕｓｅｄｉｎｔｈｅｓｔｕｄｙｏｆｃｏｍｐｌｅｘｅｓｏｆｒａｒｅｅａｒｔｈｓａｌｔｓｗｉｔｈａｍｉｎｏａｃｉｄｓｂｅｃａｕｓｅｒａｒｅｅａｒｔｈｉｏｎｓｐｏｓｓｅｓｓｓｏｍｅｓｐｅｃｉａｌｆｕｎｃｔｉｏｎｓｉｎｂｉｏｃｈｅｍｉｓｔｒｙ .Ｔｈｅｙｃａｎｂｅｕｓｅｄａｓａｐｒｏｂｅｔｏｌａｂｅｌｔｈｅｃａｌｃｉｕｍｉｏｎ .Ｍｏｒｅｏｖｅｒ,ａｍｉｎｏａｃｉｄｓａｒｅｔｈｅｓｔｒｕｃｔｕｒｅｕｎｉｔｏｆｐｒｏｔｅｉｎｓ .Ｇａｏａｎｄｃｏｗｏｒｋｅｒｓｒｅｃｅ…     

Phase Chemistry of the Complexes of RE Amino Acids

Forty-three phase diagrams of ternary system concerning rare earth salts, a-amino acids and water,which were constructed by phase equilibrium methods, were expounded. The influences of the factors such as cations, anions, the structure of amino acids, temperature on the phase diagrams were discussed. Under the guidance of phase equilibrium results, over 150 new solid complexes were prepared. IR, reflecting, UV, FS, and Raman spectra for these complexes were investigated and the regularity of ““tripartite effect“, “tetrad effect“,“Nephelanxeric effect“, “Oddo-Harkins“ was observed. Thermal decomposition processes of the complexes were confirmed. Based on the comparison with the known crystal structures of rare earth-amino acid-complexes, an estimarion method for predicting the crystal structure data of series complexes was founded. The constant volume combustion energies of the complexes were determined by RBC-1 type rotating bomb calorimeter. The standard enthalpies of combustion and standard enthalpies of formation were calculated for these complexes.     

Performance of Low Fluoride Dephosphorization Slag of Hot Metal

 The purpose of this study is decreasing content of CaF2 in dephosphorization slag. The dephosphorization effects with CaF2 replaced by B2O3 were investigated. The dephosphorization experiments were carried at 1450℃ in air atmosphere. The results show that the melting points and dephosphorization ratios change little when B2O3 replaced CaF2. The dephosphorization ratios which are all greater than 80% and melting points can meet the requirement of hot metal pretreatment. Because of the change of alkalinity caused by B2O3, the oxidation of slag increases with increasing of B2O3 contents. It is beneficial to pre-dephosphorization. As a result, for decreasing its pollution, CaF2 can be replaced by B2O3 to dispose fluoride-free pre-dephosphorization slag.     

Effect of Cerium on Morphology of Phosphide Eutectic

At present, in cast iron fine melting, lowering phosphorus concentration with no loss ofother favorable elements at the same timeseems to be a problem, which still has notbeen solved thoroughly. Therefore, looking foran appropriate nodulizer to modify the morphology of phosphide eutectic, especially inhigh strength cast iron, is necessary. On theother hand, phosphorous can also exhibit itsfaVorable effect on mechanical properties aswell as processing behaviors. For instance,gray cast iron cont…     

Effects of Lanthanum on Redox Systems in Plasma Membranes of Casuarina equisetifolia Seedlings Under Acid Rain Stress

Theplasmamembraneisapenetrablebarrier ,whichcancontroltheexchangeofsubstancesacrossmembranesincells ,andalsoistheintermediumandreceptorofenergyorinformationtransferencebetweencellsandenvironment.Theplasmamembraneredoxsystem(PMRS)meanstheelectrontransferchainsonplasmamembrane .Owingtohavethepossibilityofejectingprotons ,energizingplasmamembraneandhavingthefunctionofacceleratingtransportationofsoluteacrossmembrane ,theplasmamembraneredoxsystemswerepaidmuchattentionto[1] .Acidrainisoneofthemost…     

The Role of the Plasma Membrane H+-ATPase in Plant-Microbe Interactions

T Plasma membrane (PM) H+-ATPases are the primary pumps responsible for the establishment of cellular membrane potential in plants. In addition to regulating basic aspects of plant cell function, these enzymes contribute to signaling events in response to diverse environmental stimuli. Here, we focus on the roles of the PM H+-ATPase during plantpathogen interactions. PM H+-ATPases are dynamically regulated during plant immune responses and recent quantitative proteomics studies suggest complex spatial and temporal modulation of PM H+-ATPase activity during early pathogen recognition events. Additional data indicate that PM H+-ATPases cooperate with the plant immune signaling protein RIN4 to regulate stomatal apertures during bacterial invasion of leaf tissue. Furthermore, pathogens have evolved mechanisms to manipulate PM H+-ATPase activity during infection. Thus, these ubiquitous plant enzymes contribute to plant immune responses and are targeted by pathogens to increase plant susceptibility.     

Control effect of lanthanum against plant disease

Effect of La on emergence, growth and development of Isatis indigotica Fort. and Festuca arundinacea seedlings was researched by pot experiments of inoculating Rhizoctonia solani and with the mixture ofRhizoctonia solani and Fusarium solani in disinfected soil after the seeds were soaked in the solution with different concentrations of La^3＋. The results indicated that infection rate decreased and there were significant disease controlling effects on seed rot, bud rot and root rot caused by pathogenic fungi when the seeds were soaked by La^3＋. Thus, the rates of emergence of Isatis indigotica Fort. and turfgrass Festuca arundinacea were increased, When La^3＋ concentration was in a proper range, the growth and development of plant seed/ings were promoted. Spraying La on rice plants showed a significant controling effect on Rhizoctonia solani. Furthermore, the EC50 of La^3＋performed 128.7 and 128.1 mg/L at 1 and 7 d after spraying La in rice plants, respectively. The EC50 of La^3＋ performed in vivo （in rice plant） was lower than that in vitro （171.9 mg/L）.     

Effect of Ln3＋ on Inhibition of Tobacco RuBPcase

Ｉｔｗａｓｐｒｏｖｅｄｂｙｐｒｅｖｉｏｕｓｗｏｒｋｓ[1] ｔｈａｔｒａｒｅｅａｒｔｈｅｌｅｍｅｎｔｓｐｒｏｍｏｔｅｔｈｅｇｒｏｗｔｈａｎｄｄｅ ｖｅｌｏｐｍｅｎｔｏｆｐｌａｎｔｓａｎｄｉｎｃｒｅａｓｅｔｈｅｙｉｅｌｄｏｆｃｒｏｐｓａｔｌｏｗｃｏｎｃｅｎｔｒａｔｉｏｎ ,ｂｕｔｗｈｅｎｔｈｅｃｏｎ ｃｅｎｔｒａｔｉｏｎｉｓｈｉｇｈ ,ｔｈｅｙｗｉｌｌｉｎｈｉｂｉｔｔｈｅｇｒｏｗｔｈｏｆｐｌａｎｔｓ .Ｉｔｗａｓａｌｓｏｐｒｏｖｅｄ[2 ,3] ｔｈａｔｒａｒｅｅａｒｔｈｅｌｅｍｅｎｔｓｅｘｈｉｂｉｔｂｏｔｈｐｏｓ…     

Development and characterization of antibodies directed against the mouse D4 dopamine receptor

Different approaches were utilized to investigate the mechanism by which fusicoccin (FC) induces the activation of the H(+)-ATPase in plasma membrane (PM) isolated from radish (Raphanus sativus L.) seedlings treated in vivo with (FC-PM) or without (C-PM) FC. Treatment of FC-PM with different detergents indicated that PM H(+)-ATPase and the FC-FC-binding-protein (FCBP) complex were solubilized to a similar extent. Fractionation of solubilized FC-PM proteins by a linear sucrose-density gradient showed that the two proteins comigrated and that PM H(+)-ATPase retained the activated state induced by FC. Solubilized PM proteins were also fractionated by a fast-protein liquid chromatography anion-exchange column. Comparison between C-PM and FC-PM indicated that in vivo treatment of the seedlings with FC caused different elution profiles; PM H(+)-ATPase from FC-PM was only partially separated from the FC-FCBP complex and eluted at a higher NaCl concentration than did PM H(+)-ATPase from C-PM. Western analysis of fast-protein liquid chromatography fractions probed with an anti-N terminus PM H(+)-ATPase antiserum and with an anti-14-3-3 antiserum indicated an FC-induced association of FCBP with the PM H(+)-ATPase. Analysis of the activation state of PM H(+)-ATPase in fractions in which the enzyme was partially separated from FCBP suggested that the establishment of an association between the two proteins was necessary to maintain the FC-induced activation of the enzyme.     

Toxic Effects of Lanthanum, Cerium, Chromium and Zinc on Potamogeton Malaianus

iththerapiddevelopmentofrareearthindustryandextensiveapplicationofrareearthinagriculture ,agreatmanyofrareearthelements (REEs)werere leasedintoenvironment ,especiallywaterenviron ment ,andtheconsequentseriousenvironmentpollu tionhasattractedpeople′satten…     

Activity of the plasma membrane H(+)-ATPase and optimal glycolytic flux are required for rapid adaptation and growth of Saccharomyces cerevisiae in the presence of the weak-acid preservative sorbic acid

The weak acid sorbic acid transiently inhibited the growth of Saccharomyces cerevisiae in media at low pH. During a lag period, the length of which depended on the severity of this weak-acid stress, yeast cells appeared to adapt to this stress, eventually recovering and growing normally. This adaptation to weak-acid stress was not due to metabolism and removal of the sorbic acid. A pma1-205 mutant, with about half the normal membrane H+-ATPase activity, was shown to be more sensitive to sorbic acid than its parent. Sorbic acid appeared to stimulate plasma membrane H+-ATPase activity in both PMA1 and pma1-205. Consistent with this, cellular ATP levels showed drastic reductions, the extent of which depended on the severity of weak-acid stress. The weak acid did not appear to affect the synthesis of ATP because CO2 production and O2 consumption were not affected significantly in PMA1 and pma1-205 cells. However, a glycolytic mutant, with about one-third the normal pyruvate kinase and phosphofructokinase activity and hence a reduced capacity to generate ATP, was more sensitive to sorbic acid than its isogenic parent. These data are consistent with the idea that adaptation by yeast cells to sorbic acid is dependent on (i) the restoration of internal pH via the export of protons by the membrane H+-ATPase in an energy-demanding process and (ii) the generation of sufficient ATP to drive this process and still allow growth.     

Oxidative damage to sarcoplasmic reticulum Ca2+-ATPase AT submicromolar iron concentrations: evidence for metal-catalyzed oxidation

The sarcoplasmic reticulum (SR) calcium ATPase carries out active Ca2+ pumping at the expense of ATP hydrolysis. We have previously described the inhibition of SR ATPase by oxidative stress induced by the Fenton reaction (Fe2+ + H2O2 --> HO. + HO- + Fe3+). Inhibition was not related to peroxidation of the SR membrane nor to oxidation of ATPase thiols, and involved fragmentation of the ATPase polypeptide chain. The present study aims at further characterizing the mechanism of inhibition of the Ca2+-ATPase by oxygen reactive species at Fe2+ concentrations possibly found in pathological conditions of iron overload. ATP hydrolysis by SR vesicles was inhibited in a dose-dependent manner by micromolar concentrations of Fe2+, H2O2, and ascorbate. Measuring the rate constants of inactivation (k inact) at different Fe2+ concentrations in the presence of saturating concentrations of H2O2 and ascorbate (100 microM each) revealed a saturation profile with half-maximal inactivation rate at ca. 2 microM Fe2+. Inhibition was not affected by addition of 200 microM Ca2+ to the medium, indicating that it was not related to iron binding to the high affinity Ca2+ binding sites in the ATPase. Furthermore, inhibition was not prevented by the water-soluble hydroxyl radical scavengers mannitol or dimethylsulfoxide, nor by butylated hydroxytoluene (a lipid peroxidation blocker) or dithiothreitol (DTT). However, when Cu2+ was used instead of Fe2+ in the Fenton reaction, ATPase inhibition could be prevented by DTT. We propose that functional impairment of the Ca2+-pump may be related to oxidative protein fragmentation mediated by site-specific Fe2+ binding at submicromolar or low micromolar concentrations, which may occur in pathological conditions of iron overload.     

镧对黑曲霉生理代谢的Hormesis效应

应用含有梯度外源镧(La)(0、16mg/L、64mg/L、256mg/L、512mg/L和1024 mg/L)的液体培养基培养黑曲霉,每间隔8h取样测定黑曲霉对还原糖和蛋白质的吸收和利用率。培养3天后,测定黑曲霉质膜三磷酸腺苷酶(ATPase),胞内乳酸脱氢酶(LDH)和淀粉酶活性,以及脂质过氧化产物(MDA)的变化。结果表明,在0～64mg/L外源La作用下,黑曲霉对还原糖和蛋白质的吸收与利用率、质膜Na+,K+-ATPase、Ca2+-ATPase、Mg2+-AT-Pase、胞内LDH酶和淀粉酶活性均随La3+的增加而升高,而MDA呈现下降趋势。在64mg/L～1024mg/L剂量范围内,上述生理指标则呈现相反的变化趋势。因此,La3+诱导了黑曲霉生理代谢的Hormesis效应。     

Dissociation of intracellular Ca2+ release and Ca2+ entry response to 5-hydroxytryptamine in cultured canine tracheal smooth muscle cells

The relationship between the agonist-sensitive Ca2+ pool and those discharged by the Ca2+ -ATPase inhibitor thapsigargin (TG) were investigated in canine tracheal smooth muscle cells (TSMCs). In fura-2-loaded TSMCs, 5-hydroxytryptamine (5-HT) stimulated a rapid increase in intracellular Ca2+ ([Ca2+]i), followed by a sustained plateau phase that was dependent on extracellular Ca2+. In such cells, TG produced a concentration-dependent increase in [Ca2+]i, which remained elevated over basal level for several minutes and was substantially attenuated in the absence of extracellular Ca2+. Application of 5-HT after TG demonstrated that the TG-sensitive compartment partly overlapped the 5-HT-sensitive stores. Pre-treatment of TSMCs with TG significantly inhibited the increase in [Ca2+]i induced by 5-HT in a time-dependent manner. Similar results were obtained with two other Ca2+ -ATPase inhibitors, cyclopiazonic acid and 2,5-di-t-butylhydroquinone. Although these inhibitors had no effect on phosphoinositide hydrolysis, Ca2+ -influx was stimulated by these agents. These results suggest that depletion of the agonist-sensitive Ca2+ stores is sufficient for activation of Ca2+ influx. Some characteristics of the Ca2+ -influx activated by depletion of internal Ca2+ stores were compared with those of the agonist-activated pathway. 5-HT-stimulated Ca2+ influx was inhibited by La3+, membrane depolarisation, and the novel Ca2+ -influx blocker 1-?beta-[3-(4-methoxyphenyl) propoxy]-4-methoxyphenethyl?-1H-imidazole hydrochloride (SKF96365). Likewise, activation of Ca2+ influx by TG also was blocked by La3+, membrane depolarisation, and SKF96365. These results suggest that (1) in the absence of PI hydrolysis, depletion of the agonist-sensitive internal Ca2+ stores in TSMCs is sufficient for activation of Ca2+ influx, and (2) the agonist-activated Ca2+ influx pathway and the influx pathway activated by depletion of the inositol 1,4,5-trisphosphate-sensitive Ca2+ pool are indistinguishable.