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1.
The effects of Ce (Ⅳ) on callus growth, anthocyanin content, and expression of anthocyanin biosynthetic genes in callus suspension cultures of Solanum tuberosum cv. Chieftain were studied by the measurement of fresh weight, spectrophotometric assays, and semiquantitative RT-PCR. The results indicate that 0.1 mmol·L-1 Ce (Ⅳ) can promote callus growth, increase the accumulation of anthocyanins, and enhance the expression of five anthocyanin biosynthetic genes (CHS, F3H, F3′5′H, DFR, and 3GT) most efficiently. At high concentrations of 1 mmol·L-1, Ce (Ⅳ) partially inhibits callus growth and at 2 mmol·L-1 eventually lends to cell death. The results show that Ce(Ⅳ) can induce the expression of anthocyanin biosynthetic genes to produce and accumulate anthocyanins and increase the yield of anthocyanins.  相似文献   

2.
Ceriumis one of the cheapest[1]and most abun-dant rare earths (RE) .However ,high purityis usual-ly required for its utilization in industry , where it isusedfor sulfur control insteels ,pyrophoric alloys ,ce-ramic ,catalyst support ,polishing powders ,etc .In its minerals ,as well as in the spent nuclearfuel ,ceriumis accompanied by other RE.They basi-cally exist in solution as stable RE(Ⅲ) species ,which makes their mutual separation rather difficult .In contrast to other RE, Ce(Ⅲ) can…  相似文献   

3.
It is knownthat rare earthions ,8-hydroxyquino-line and salicylic acid are antibacterial[1 ~5].Synthesisand characterization of the rare earth complexes withsalicylic acid were reported by Sun[6].Synthesis andcharacterization of the rare earth complexes …  相似文献   

4.
The adsorption properties of 4-amino-1,2,4-triazole resin (4-ATR) for Re(VII) were investigated by static and dynamic adsorption–desorption measurements with ultraviolet–visible spectroscopy. The influence of conditions such as temperature, initial solution pH and contact time on the adsorption curve was studied. It was found that the 4-amino-1,2,4-triazole resin was suitable for adsorption of Re(VII). The saturated adsorption capacity was 354 mg·g− 1resin at pH 2.6 in HAc–NaAc medium at 298 K. The adsorption rate constant was k298 = 8.2 × 10− 5 s− 1. The adsorption behavior of 4-ATR for Re(VII) obeyed the Freundlich empirical equation; whilst changes in adsorption with temperature gave an enthalpy change ΔH  = − 11.8 kJ·mol− 1. The molar ratio of the functional group of 4-ATR to Re(VII) was about 2:1. Re(VII) adsorbed on 4-ATR was eluted by 1.0 ~ 5.0 mol·L− 1 HCl with 100% quantitative elution in 4.0 mol·L− 1 HCl solution. The resin can be regenerated and reused without apparent decrease in adsorption capacity.  相似文献   

5.
In the novel clean chromate production process, the alkali liquor recycled to decompose the chromite ore mainly consists of KOH and K2CO3 which accumulates aluminium impurity and affects the quality of the product greatly. Aluminium impurity can be removed by adding CaO to precipitate as 3CaO · Al2O3 · 6H2O (C3AH6). A study of the effects of various parameters, such as KOH concentration, K2CO3 concentration and temperature on the behaviour of C3AH6 show that C3AH6 is decomposed to 3CaO · Al2O3 · CaCO3 · 11H2O and CaCO3 below 150 g L− 1 KOH, and decomposed to Ca(OH)2 above 150 g L− 1 KOH. With K2CO3 concentration increasing, C3AH6 decomposes significantly, which results in more CaCO3 or 3CaO · Al2O3 · CaCO3 · 11H2O produced. Temperature has a large positive effect on the decomposition of C3AH6 at 45 g L− 1 KOH but has no significant effect at 150 g L− 1 KOH. The optimal condition for removing aluminium impurity in the KOH + K2CO3 + H2O system is 150 g L− 1 KOH, 50 g L− 1 K2CO3 and 80 °C.  相似文献   

6.
Europiumis one of the most important rare earth(RE) element .It is widely used as a component ofcathode ray tubes , with screen coated with red phos-phor ,as phosphorescent pigments ,andinlaser optics .It can also be used as neutron-absorbing material .In…  相似文献   

7.
The effect of NO on lanthanum-induced antioxidant activities in rice was evaluated. The results showed that the uptake and translocation of La from root to shoot were obviously inhibited by 10μmol·L^-1 sodium nitropmsside (SNP), a donor of NO, in the seedlings grown in Mura B nutrient solution with 100μmol·L^-1 La. Although the content of ascorbate acid (AsA) were scarcely affected by La or NO in our experiment, La decreased significantly the activity of SOD and content of GSH, while promoted H202 content in leaves. Furthermore, NO blocked these La effects. Taken together, the results suggested that NO relieved La toxicity in rice. A possible role for NO effects on antioxidant activity was discussed.  相似文献   

8.
(Bi2O3)0.73(Y2O3)0.27 fine powders prepared by wet chemical precipitation method were cold isostatically pressed to form solid electrolyte tubes, and sintered at 900 ℃ for 10 h in the air. Their pumping oxygen characteristics in non-dehydrated Ar gas were investigated, where a ZrO2 (Y2O3 stabilized) oxygen sensor was used to measure the oxygen partial pressure Po2. The results showed that the Po2 value reached magnitudes of 1×10^-2-1×10^-10 Pa at the applied pumping oxygen voltage of 0.5 V, 1×10^-37-1×10^-27 Pa at 1.0 V and 1×10^-53-1×10^47 Pa at 2.0 V within the temperature range from 550 to 650 ℃. Moreover, no cracks were found in the tested solid electrolyte tubes. Thus, the Bi2O3-Y2O3 system might be used in solid electrolyte oxygen pump for purifying gases.  相似文献   

9.
Results of density and viscosity measurements for aqueous solutions of MgCl2 (0.5–3.5 mol L− 1) and MgCl2 + 10% NiCl2 (0.5–3.5 mol L− 1) at temperatures of 25, 60 and 90 °C show an almost linear increase in density with total concentration, while low nickel contents and temperature have comparatively small effects. Viscosities of MgCl2 solutions rise sharply at 25 °C but are significantly lower at 90 °C. The viscosity of 3–4 mol kg− 1 MgCl2 at 90 °C is similar to water at 25 °C. Nickel has no significant effect on the viscosity of these solutions.Results of heat capacity measurements for aqueous solutions of MgCl2 (0.5–3.5 mol L− 1) and MgCl2 + 10% NiCl2 (0.5–3.5 mol L− 1) at temperatures of 60 and 90 °C show that the heat capacities of these solution decrease significantly with total concentration, while the effects of low nickel contents and temperature are again comparatively small.  相似文献   

10.
It is well known that sulfur dioxide(SO2) , morethan50%of which arise fromcombustion of fossil fu-els ,are precursors of acidrain andtheir emission pos-es a global threat tothe atmosphere .Environmental a-gencies have ,therefore ,regulated emissions of SO…  相似文献   

11.
The diameter of the colony of Fusarium oxysporum in solid medium, and the mycelium growth, pectinase activity, and mycelium permeability of Fusarium oxysporum in liquid medium under varying concentrations of Nd^3+ (0, 2, 4, 10, 20, 40, 60, 80, 100, 120, 140, 160, 180, 200, 300, and 400 mg·L^-1) were measured. The results indicated that the growth of Fusarium oxysporum was stimulated in solid medium when the concentration of Nd^3+ ranges from 2 to 180 mg·L^-1, whereas it was inhibited when Nd^3 + concentration was greater than 200 mg· L^-1. The colonies were fewer and smaller when Nd^3 + was used in the solid medium. The growth of Fusarium oxysporum was inhibited in liquid medium when Nd^3+ was used. The inhibition rate showed by the dry weight of mycelium ranged from 4.83% to 52.18% and inereased with Nd^3 + concentration. The pectinase activity decreased compared with that of controls. When the concentration of Nd^3 + was 10 and 400 mg· L^- 1, the pectinase activity decreased by 95 % at both concentrations. Mycelium cell membrane permeability increased when Nd^3 + concentrations ranged from 10 to 400 mg· L^-1 but decreased when Nd^3+ concentration was 2 mg· L^-1.  相似文献   

12.
(C5H5)3Ln(THF)reacted with amine bis(phenol) LH2 [ L = Me2NCH2CH2N {CH2-(2-O-C6H2-But^1-3-Me- 5)}2 ] in a 1:1 molar ratio in THF to generate the amine bis(phenolato) cyclopentadienyl lanthanide complexes LLn(C5H5) (THF)·(THF),(Ln = La (1), n =0; Ln = Sm(2), n = 1) in high yields. Complexes 1 and 2 were fully characterized by elemental analysis, NMR (for 1) and IR spectra, and X-ray structural determination. The crystal data of complex 1 are monoclinic, P21/c space goup, a= 1.1595(1) nm, b = 1.8588(2) nm, c = 1.6647(1) nm, β = 98.490(2)°, V =3.5486(5) nm^3, Z =4, Dc = 1.338 mg· m^3,μ = 1240 mm^-1, F(000)= 1488, R =0.0249, wR = 0.0568. The crystal data of complex 2 are monoclinic, P21/c sp ace goup, a = 0.9692 (1) nm, b = 1.4583 (2) nm, c = 2.8192 (3) nm, = 96.805 (2)°, V = 3.9584 (7) nm^3, Z=4, Dc =1.340 mg · ma, μ = 1.524 mm^-1, F(000)= 1668, R =0.0346, wR =0.0756. The attempts failed to synthesize the amine bis(phenolate) lanthanide alkoxides by the reactions of complexes 1 and 2 with alcohols. The preliminary results revealed that complex 1 can initiate ε-caprolactone polymerization.  相似文献   

13.
A A cerium-based chemical conversion process was studied. First, zinc coating obtained from a free-cyanide alkaline bath, with derivative of imidazol with new brightener, was investigated, zinc-plated steel specimens were treated with a solution of 50 mmol· L^-1 Ce(NO3 )3 The corrosion behavior of bare and treated mild galvanized steel was evaluated during exposure to 0.5 mol · L^-1 NaCl for different immersion time, using Tafel polarization curves and electrochemical impedance spectroscopy (EIS) measurements. The surface morphology of the coating was studied using scanning electron microscopy (SEM). The composition and chemical percent of the coating were examined by X-ray dispersion energy (EDAX). The results of these measurements showed that the newly developed cerium-based conversion coating process was a promising candidate for replacing the conventional chromate treatments used at present for galvanized steel.  相似文献   

14.
The scavenging of molybdenum from MnSO4 solution with freshly precipitated “nascent” Mn3O4 is reported. Firstly, nascent Mn3O4 was prepared from MnSO4 solution by adding NaOH and aerating. The aeration time had a significant influence on the preparation of nascent Mn3O4, but other factors such as pH and ageing time had little effect. SEM, XRD, particle size and surface area analysis were used to characterize nascent Mn3O4. A study was then carried out on the effects of time, concentration of Mn, initial pH, temperature and dosage of nascent Mn3O4 on the adsorption of Mo from MnSO4 solution. The results showed that the concentration of Mo in 70–200 g L− 1 MnSO4 at pH 1–3 could be reduced from about 1 mg L− 1 to less than 0.015 mg L− 1 in 30 min at 80 °C by the addition of about 0.3 g L− 1 nascent Mn3O4 in suspension. Accordingly, the removal capacity of nascent Mn3O4 can reach 4.42 mg Mo/g Mn3O4. This Mo removal exceeds the requirement for special electrolytic MnO2 used in the production of alkaline zinc–manganese batteries.  相似文献   

15.
The complex of lanthanum chloride with Glycine and Alanine, La(Gly)2(Ala)3Cl3 · 2H2O, was synthesized and characterized by IR, elementary analysis, thermogravimetric analysis, and chemical analysis. The dissolution enthalpies of LaCl3 · 7H2O(s), 2Gly(s) + 3Ala(s) and La(Gly)2(Ala)3Cl3 · 2H2O(s) were determined in 2 mol · L−1 HCl by a solution-reaction isoperibol calorimeter. By designing a thermochemical cycle in terms of Hess' Law and through calculation, the reaction enthalpy of lanthanum chloride seven-hydrate with Glycine and Alanine was obtained: ΔrHθm(298.15 K) = (29.652 ± 0.504) kJ · mol−1, and the standard enthalpy of formation of La(Gly)2(Ala)3Cl3 · 2H2O(s) ΔfHθm[La(Gly)2 (Ala)3Cl3 · 2H2O, s, 298.15 K] = −4467.6 ± 8.3 kJ · mol−1.  相似文献   

16.
Zirconium dioxide is a significant material withgood physicochemical characteristics . It is used inmanyfields such as energysources ,material and envi-ronment . Cubic phase zirconium dioxide doped withyttria (YSZ) is alreadyin wide use in solid oxygenfu-…  相似文献   

17.
Ceriumiswidelyusedinindustry,mainlyinthe formofceria(CeO2),asamaterialforceramic,cata lysts,polishingpowdersandsoon.Inmetallurgyceri umhasbeenusedassulfidecontrollingadditivefor steelandotheralloys.Itsabundanceinvariousminer als,inwhichCebeisaccompaniedbyotherrare earths,makesCeoneofthecheapestRE[1].Ce(Ⅲ),incontrasttootherbasicallytrivalentREions,canbe oxidizedtorelativelystableCe(Ⅳ)statethathas quitedifferentchemicalproperties.Tetravalentcerium isusedasanoxidizingagentinorganicsynthesis…  相似文献   

18.
A complete characterization was carried out on a jarositic residue from the zinc industry. This residue consists of ammonium jarosite, with some contents of H3O+, Ag+, Pb2+, Na+ and K+ in the alkaline “sites” and, Cu2+ and Zn2+ as a partial substitution of iron. The formula is: [Ag0.001Na0.07K0.02Pb0.007(NH4)0.59(H3O)0.31]Fe3(SO4)2(OH)6. Some contents of franklinite (ZnO·Fe2O3), gunninguite (ZnSO4·H2O) and quartz were also detected. The jarosite is interconnected rhombohedral crystals of 1–2 μm, with a size distribution of particles of 2–100 μm, which could be described by the Rosin–Rammler model.The alkaline decomposition curves exhibit an induction period followed by a progressive conversion period; the experimental data are consistent with the spherical particle with shrinking core model for chemical control. The alkaline decomposition of the ammonium jarosite can be shown by the following stoichiometric formula:NH4Fe3(SO4)2(OH)6(s)+3OH(aq)→(NH)4(aq)++3Fe(OH)3(s)+2SO4(aq)2−.The decomposition (NaOH) presents an order of reaction of 1.1 with respect to the [OH] and an activation energy of 77 kJ mol−1. In NaOH/CN media, the process is of 0.8 order with respect to the OH and 0.15 with respect to the CN. The activation energy was 46 kJ mol−1. Products obtained are amorphous. Franklinite was not affected during the decomposition process. The presence of this phase is indicative that the franklinite acted like a nucleus during the ammonium jarosite precipitation.  相似文献   

19.
Eu-chelate were used to construct a two-site sandwich-type assay for pepsinogen I (PGI) with time-resolved flu-oroimmunoassay (TRFIA) as a detection technique. On the noncompetitive assay, captured monoclonal antibodies (McAbs) coated on wells were directed against a specific antigenic site on the PGI. Another McAbs, called as labeling McAbs, were prepared with the Eu-chelate of N-(p-isothiocyanatobenzyl)-diethylenetriamine-N, N, N, N-tetraacetie acid and directed against a different antigenic site on the PGI. The fluorescence counts of bound Eu3+ -McAbs were measured with the auto DELFIA1235 system. The PGI in sera from healthy volunteers were determined by PGI-TRFIA. The within-run and between-run CVs of the PGI-TRFIA were 1.9% and 4.7%, respectively, and the recovery rate was 102.65%. The assay had a detection limit of 0.05 μg·L−1. The PGI-TRFIA provided a linear response from 3.5 to 328 μg·L−1. The cross-reacting rate with pepsinogen II was negligible. The linear correlation of PGI-TRFIA and radioimmunassay measurements resulted in a correlation coefficient of 0.977. The means of healthy volunteers were 154 ± 43 μg·L−1 for serum PGI. The availability of a highly sensitive, reliable, and convenient method for quantifying PGI will allow investigations into the possible diagnostic value of this analyte in various clinical conditions, including gastric carcinoma, duodenal ulcer, gastritis and severe atrophic gastritis.  相似文献   

20.
Research on bismuthlayer structuredferroelectricceramics as piezoelectric material with high Curie tem-perature ,strong anisotropic characters ,lowdielectricdissipationfactor and lowaging rate has attracted in-creasing interest[1,2].It can be used to manu…  相似文献   

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