Structure and Growth Mechanism of Lanthanum Chromate

The unit cell of lanthanum chromate was constructed by calculating equivalent points. By means of calculation of the hole octahedrally surrounded by O^2- ions, it was considered that the sintered property of lanthanu,n chromate and the stability of Cr - O octahedron might be promoted by mixing a little Ca^2 ions. The growth mechanism was discussed in terms of structural ledge observed by SEM, the surfaces of the structural ledges parallel to (001), (010) and (110)planes, respectively. The misfit between (110) and (001) planes is only 0.0021 on common atomic plane, and the interconnection of the structured ledge may occur during crystal growth.     

Microstructures and Phase Transition Points of As-Cast Mg-Zn-Y System Alloys

As-east mierostruetures and their distribution of Mg-Zn-Y ternary alloy with high magnesium, low zinc and yttrium were examined using Nikon Epiphot optical microscopy （OM）, RigakuD/max-3C X- ray diffraetion （XRD）, and JEOL JSM-6700F scanning electron microscopy （SEM） equipped with an energydispersive X-ray spectroscopy （EDS）. In the as-east mierostructures, Yttrium and zinc tend to segregate at grain boundaries,     

Sol-Gel Preparation and Phase Transition of RE Orthoborates

ｈｏｓｐｈｏｒｓｔｈａｔｗｏｒｋｕｎｄｅｒＶＵＶｅｘｃｉｔａ ｔｉｏｎ ,ａｓａｋｉｎｄｏｆａｄｖａｎｃｅｄｆｕｎｃｔｉｏｎａｌｍａｔｅｒｉ ａｌ ,ｃａｎｂｅａｐｐｌｉｅｄｉｎｍｅｒｃｕｒｙ ｌｅｓｓｆｌｕｏｒｅｓ ｃｅｎｃｅｌａｍｐｓａｎｄｐｌａｓｍａｄｉｓｐｌａｙｐａｎｅｌｓ .Ｔｈｅｒａｒｅｅａｒｔｈｂｏｒａｔｅｓ ,ｗｉｔｈｅｘｃｅｐｔｉｏｎａｌｄａｍａｇｅｔｈｒｅｓｈｏｌｄａｎｄｈｉｇｈｌｕｍｉｎｅｓｃｅｎｔｅｆｆｉｃｉｅｎｃｙ ,ａｒｅｐｒａｃｔｉｃａｌＶＵＶｐｈｏｓｐｈｏｒｓ .Ｈｏｗｅｖｅｒ ,…     

Development of Doped Lanthanum Gallate Solid Electrolytes

Development of the doped lanthanum gallate solid electrolytes in the recent years was reviewed. The structure and oxygen ion transference mechanism were discussed. Effects of alkali earths, transition metals, and impurities on electrical conductivity of the doped lanthanum gallates were also discussed. The applications of doped lanthanum gallate were described. The current problems and corresponding strategies were explored.     

Tribological Behavior of Lanthanum Phosphate and Zinc Dialkyldithiophosphate and Their Mixture as Additives in Lithium Grease

Tribological Behavior of Lanthanum Phosphate and Zinc Dialkyldithiophosphate and Their Mixture as Additives in Lithium Grease     

Influence of Lanthanum on Fluorescence Properties of Ag-BaO Thin Films

Ag-BaO thin films doped with lanthanum were prepared by vacuum deposition. Compared with the normal Ag-BaO thin film, there is almost no change with the shape and the peak site of the fluorescence spectrum; however, fluores-cence emission strength of the whole observation band(325 -600 nm)increases about 40%, and the increase of short wavelength range is more remarkable than that of long wavelength range, which we named “blue-stronger“ phenomenon. Analytic results show that, with the forming of intermetallic compounds between silver and lanthanum, the 4f-state energy levels lie just below the Fermi level within 5 eV. It is the energy exchange between the 4f energy levels and the conduction band that causes the increase effect of fluorescence emission, and it is the optical absorption cross section of 4f electron, which increases with the increase of energy of incidence photon, that gives rise to the “blue-stronger“ phenomenon.     

Preparation of Ca Doped Lanthanum Chromite by Sol-Gel Process

Super fine particles of calcium-doped lanthanum chromites were prepared by the sol-gel process in which the chelating agent was citric acid and the dispersant agent was ethylene glycol. The phase of fine particles was analyzed by XRD and the size and shape of the particles were investigated by TEM. The result shows that the nano-particles of La1-xCaxCrO3 can be obtained by the way of Ca2 complex singly with citric acid and being calcined at 700 ℃.     

Effect of Lanthanum on RuBPCase Activity of Tobacco Seedlings

Ｉｔｗａｓｐｒｏｖｅｄ[1] ｔｈａｔｒａｒｅｅａｒｔｈｅｌｅｍｅｎｔｓ(ＲＥＥ)ｐｒｏｍｏｔｅｔｈｅｇｒｏｗｔｈａｎｄｄｅｖｅｌｏｐｍｅｎｔｏｆｐｌａｎｔｓ ,ａｎｄｉｎｃｒｅａｓｅｔｈｅｙｉｅｌｄｏｆｃｒｏｐｓ .Ｈｏｗ ｅｖｅｒ ,ｔｈｅｉｒｍｅｃｈａｎｉｓｍａｒｅｓｔｉｌｌｌｉｔｔｌｅｋｎｏｗｎ .ＩｔｗａｓｋｎｏｗｎｔｈａｔＲＥＥｉｎｃｒｅａｓｅｓｔｈｅａｃｔｉｖｉｔｉｅｓｏｆｓｏｍｅｅｎｚｙｍｅｓａｎｄａｃｃｅｌｅｒａｔｅｓｔｈｅｐｒｏｃｅｅｄｉｎｇｏｆｐｈｏｔｏｓｙｎｔｈｅｓｉｓｉｎｐｌａｎｔｓ …     

Subchronic Toxicity of Lanthanum Nitrate on Liver in Rats

ｌｏｎｇｗｉｔｈｔｈｅｗｉｄｅｓｐｒｅａｄａｐｐｌｉｃａｔｉｏｎｏｆｔｈｅＲＥＥｉｎａｇｒｉｃｕｌｔｕｒｅ ,ａｎｉｍａｌｈｕｓｂａｎｄａｒｙａｎｄｍｅｄｉｃｉｎｅｏｆｏｕｒｃｏｕｎｔｒｙ ,ｔｈｅｉｎｃｒｅａｓｉｎｇｃｏｎｃｅｒｎｗｉｔｈｔｈｅＲＥＥｃａｌｌｓｆｏｒｔｈｅｘｔｅｎｓｉｖｅｓｔｕｄｉｅｓｏｎｔｈｅｉｒｍｅｔａｂｏｌｉｃａｃｃｕｍｕｌａｔｉｏｎａｎｄｂｉ ｏｌｏｇｉｃａｌｅｆｆｅｃｔｓ .ＴｈａｔｓｏｍｅｃｅｌｌｓｃａｎｔａｋｅｉｎＲＥＥｂｙｍｅａｎｓｏｆｐｈａｇｏｃｙｔｏｓｉｓｏｒｐｉ…     

Effects of Lanthanum Ion and Its Complexes on Permeability of Pollen Plasmalemma and Pollen Germination

Effects of Lanthanum Ion and Its Complexes on Permeability of Pollen Plasmalemma and Pollen Germination     

Effects of Lanthanum on Hydrolytic Enzyme Activities in Red Soil

The effects of La on some hydrolytic enzyme activities in red soil were studied in incubation and pet culture experiments. In the incubation experiment, La slightly stimulates the activities of urease and acidic phosphatase in soil and strongly stimulates sucrase activity in soil. In the pet culture experiment, La stimulates the activities of urease, acidic phosphatase and sucrase to different degrees. The stimulative effects of rare earth elements (REE) on hydrolytic enzyme activities in soil may result in increasing yield of eivps.     

Mechanochemical Reaction of Lanthanum Carbonate with Sodium Hydroxide and Preparation of Lanthanum Oxide Nanoparticle

Ｔｈｅｉｍｐｏｒｔａｎｃｅｏｆｎａｎｏｓｉｚｅｄｒａｒｅｅａｒｔｈｏｘｉｄｅｐｏｗｄｅｒｓｉｎｖａｒｉｏｕｓｔｅｃｈｎｉｃａｌａｐｐｌｉｃａｔｉｏｎｓｍａｋｅｓｔｈｅｉｒｐｒｅｐａｒａｔｉｏｎｔｅｃｈｎｏｌｏｇｙａｎｉｎｔｅｒｅｓｔ ｉｎｇｓｕｂｊｅｃｔｆｏｒｒｅｓｅａｒｃｈｗｏｒｋ[1 ] .Ｏｖｅｒｔｈｅｐａｓｔｄｅｃａｄｅｓ,ｍａｎｙｐｒｅｐａｒａｔｉｏｎｍｅｔｈｏｄｓｏｆｎａｎｏ ｓｉｚｅｄｒａｒｅｅａｒｔｈｏｘｉｄｅｓｈａｖｅｂｅｅｎｄｅｖｅｌｏｐｅｄ ,ｉｎｃｌｕｄｉｎｇｐｈｙｓｉｃａｌａｎｄ…     

Mechanism of Effect of Lanthanum Nitrate on Vigor of Aged Rice Seeds

Ｓｅｅｄｓｅａｒｌｙｄｅｇｅｎｅｒａｔｅｄｏｒａｇｅｄｂｙｕｎ ｓｕｉｔａｂｌｅｃｕｌｔｉｖａｔｉｏｎｏｒｕｎｓｔｏｒａｇｅｔｅｃｈｎｉｑｕｅｓｍａｙｒｅｓｕｌｔｉｎｄｅｃｒｅａｓｉｎｇｏｆｓｅｅｄｖｉｇｏｒａｎｄｏｆｔｈｅｃｒｏｐｓｏｕｔｐｕｔ,ｅｓｐｅｃｉａｌｌｙｆｏｒｒｉｃｅ.Ｒａｒｅｅａｒｔｈｓａｃｃｅｌｅｒａｔｅｔｈｅｇｅｒｍｉｎａｔｉｏｎａｎｄｇｒｏｗｔｈｏｆｔｈｅｃｒｏｐｓ ,ｓｕｃｈａｓｒｉｃｅ ,ｗｈｅａｔ,ｂａｒｌｅｙ ,ｖｅｇ ｅｔａｂｌｅｓａｎｄｏｉｌｐｌａｎｔｓ[1～ 3] .Ｔｈｅｓｔ…     

Existing Forms of Lanthanum in Purity Steels

Adding lanthanum to carbon-manganese purity steel, the existing forms of lanthanum were investigated. The results show that enrichment on grain boundary and solid solution in cementite are two kinds of important existing forms of lanthanum relating to micro-alloyed action. As a result of enrichment of lanthanum, the concentration of lanthanum aggregated on somewhere of grain boundary reaches as high as tens of times of its average content although the average content is very low. In addition, lanthanum atoms can replace partial Fe atoms that constitute cementite to form alloyed cementite, the solid solution amount of lanthanum in alloyed cementite increases as the increase of its average content in purity steel.     

Phase composition of SiC-ZrO2 composite materials synthesized from zircon doped La2O3

A study was carried out to determine the optimum parameters for synthesis of SiC-ZrO2 composite materials by carbothermal re-duction of zircon. Test samples were prepared by mixing average mesh size of less than 30 μm of carbon black and 40 μm of zircon with C/ZrSiO4 mass ratio of 0.2 and the extra addition amount of La2O3 was 0, 1 wt.% and 2 wt.%. Prepared samples were subjected to the car-bothermal reduction process at temperatures of 1723, 1753, 1773 and 1803 K for 4 h, respectively. The carbothermal reduction process was conducted in an atmosphere controlled tube furnace at an argon flow of 1.5 L/min. All products were examined by X-ray diffraction (XRD) to determine the transformation. The results showed that the best transformation of SiC-ZrO2 composite materials occurred at 1803 K for 4 h with the amount of 2 wt.%La2O3.     

Effect of Lanthanum on Plants under Supplementary Ultraviolet-B Radiation： Effect of Lanthanum on Flavonoid Contents in Soybean Seedlings Exposed to Supplementary Ultraviolet-B Radiation

The effects of solar ultraviolet-B (UV-B,280 ~320 nm) radiation on plants have been studiedintens-ively over the last two decades ,associated withthe re-search onthe biological i mpacts of stratospheric ozonedepletion .There are a large number of reports aboutthe effects of UV-B radiation on crops[1 ~5].Flavonoidcompounds , as secondary metabolites are consideredto play a major role in protecting plants from UV-Bdamage[6].These flavonoids generally absorbthe lightinthe region of 280 ~320 n…     

Synthesis and Characterization of Lanthanum Complexes with Amino Acid Schiff Base

Ｉｎｔｈｅｌｉｖｉｎｇｂｅｉｎｇｓ ,ｃａｌｃｉｕｍｉｏｎｐｏｓｓｅｓｓ ｅｓｍａｎｙｋｉｎｄｓｏｆｉｍｐｏｒｔａｎｔｂｉｏｌｏｇｉｃａｌｆｕｎｃｔｉｏｎ .Ｔｈｅｒａｄｉｕｓａｎｄｔｈｅｃｏｏｒｄｉｎａｔｅａｃｔｉｏｎｏｆｌａｎ ｔｈａｎｕｍｉｏｎａｒｅｓｉｍｉｌａｒｔｏｔｈａｔｏｆｃａｌｃｉｕｍｉｏｎ .Ｃｏｎｓｅｑｕｅｎｔｌｙ ,ｌａｎｔｈａｎｕｍｉｏｎ ,ｗｈｉｃｈｅｎｔｅｒｓｔｈｅｂｏｄｙ ,ｗｉｌｌｒｅｐｌａｃｅｃａｌｃｉｕｍｉｏｎａｎｄｓｈｏｗａｓｅｒｉｅｓｏｆｂｉｏｌｏｇｉｃａｌｅｆｆｅｃｔｓ…     

Effect of Lanthanum on Mechanical Properties of ZL702 Alloy at Room and High Temperature Condition

Effect of Lanthanum on Mechanical Properties of ZL702 Alloy at Room and High Temperature Condition     

Synthesis, Characterization and Antitumor Activity of Lanthanum(Ⅲ) Complex with Demethylcantharidate

A novel complex of lanthanum(Ⅲ) with demethylcantharidate group (DCA), Na[La(DCA)2(H2O)], was synthesized in aqueous solution and characterized by elemental analysis, molar conductance, IR, UV, 1H-NMR spectra and TG-DTA. The results suggest that lanthanum ion is seven-coordinated. Six oxygen atoms are from carboxyl groups and cyclic ethers of two DCA ligand, and on oxygen is from a H2O. The antitumor activities of the complex against HL-60 human leukemia, BGC-823 human gastric carcinoma, Bel-7402 human hepatic carcinoma, Hela human cervical carcinoma were investigated with MTT or SRB assays. Na[La(DCA)2(H2O)] exhibits stronger inhibition against certain kinds of cancer cells than Na2DCA in vitro.