Dysprosium Research Articles

Correlation of Pr, Dy, and Tb addition with physical properties of InP layers prepared by liquid phase epitaxy

The characterisation of thick (>10 μm) InP layers prepared by liquid phase epitaxy with Pr, Dy and Tb rare earth element (REE) addition in the growth melt for applications in radiation detector structures is reported. A significant improvement of all the studied parameters with increasing concentration of REE up to critical value (0.25 wt%) was observed. The structural defect density was reduced by one order of magnitude and the residual impurity concentration by three and a half order of magnitude (< 1015 cm–3). The conductivity has been changed from n to p-type when REE exceeded certain concentration limit in the melt (0.15 wt% for Pr, 0.05 wt% for Tb and 0.03 wt% for Dy). The low-temperature photoluminescence (PL) spectra narrowed and the corresponding fine lines were resolved. Comparison of PL peaks of n and p- type conducting layers with the obtained electrical data leads to the conclusion that the dominant acceptor impurity for the n to p-type crossover is Ge for Pr addition and Mn for Tb and Dy addition.

Microstructure and hard magnetic properties of atomized iron-neodymium-boron powder: O. Tong et al. (Academy of Science, Beijing, China). PM Technology, vol 13, no 1, 1995, 3–7. (In Chinese.)

The Sm-Co/Fe-Co and Sm-Co/Fe-Co-Dy nanowire arrays with smaller diameter are prepared by electrochemical deposition on the anodic aluminum oxide (AAO) templates in this paper. The crystal structure and magnetic properties of nanowires are characterized and analyzed. It is found that the Sm-Co nanowires change from amorphous phase to nanocrystalline state with hard magnetic characterization through annealing at 660 °C for 3 h. In this experiment, rare earth element Dy is added to the Fe-Co solution, and the three alloy nanowires are prepared and researched for the first time. The addition of Dy element produces a new Fe23Dy6 phase in the nanowires. The magnetic hysteresis loops illustrate that the magnetic properties of as-deposited nanowires is improved dramatically after heat treatment and the direction parallel to the nanowire arrays is the easy direction of magnetization which leads to nanowires possessing obvious shape anisotropy. The effect of different Dy ion concentration on nanowires' magnetic properties is investigated in this paper.

Formation Range and Thermal Stability of Cu-rich Cu&ndash;Mg&ndash;Ln (Ln=La, Sm, Eu, Tb, Er or Lu) Amorphous Alloys Tinged with Gold Color

Cu-rich amorphous alloys with Cu concentrations above 80 at% were formed in melt-spun Cu–Mg–Ln (Ln=La, Sm, Tb, Er or Lu) alloys. The amorphous alloys containing more than 84 at%Cu exhibit a gold-like color with high glossiness of about 450%. The glossiness decreases to about 78% by the precipitation of a crystalline phase in the amorphous phase. The Cu-rich amorphous alloys are formed in wider composition ranges for the alloys containing the Ln (Ln=Ce, Pr, Nd, Sm, Gd, Tb, Dy or Ho) elements with intermediate atomic radii of 0.175 to 0.183 nm. The formation of the Cu-rich amorphous alloys is attributed to the simultaneous dissolution of the three elements with significantly different atomic size ratios and large negative heats of mixing. The crystallization temperature (Tx) is in the range of 490 to 602 K and there is a tendency for Tx to decrease with increasing atomic number, i.e., with decreasing atomic radius of the Ln elements. The finding of the Cu-rich amorphous alloys with the gold-like color and high glossiness is important for future development of Cu-rich amorphous alloys as an engineering material.

Theoretical Calculations on Rare Earth Elements in Barium Fluoride Crystal

In the present work we used Hartree-Fock-Slater local-density discrete variational method to calculate the energy level of some rare earth doped BaF2 crystals and proposed that the Eu, Dy and Yb elements will change their valence from +3 to +2 under irradiation and thus change the optical properties of the crystals. The results show that this radiation effect model is in good agreement with experiments.

The Radiation Effect Mechanism of Some Rare Earth Doped BaF2 Crystal

ABSTRACTIn this paper, we used the Discrete Variational Xα, (DV-Xα) method to calculate the energy level of some rare earth doped BaF2 crystals and indicated that the Eu, Dy and Yb elements will change their valence from +3 to +2 under irradiation and thus change the optical properties of the crystals.The results show that this radiation effect model presented agree well with experiments.

Investigation on Mössbauer spectra of151Eu double rare-earth oxides

The151Eu double rare-earth oxides (EuR)O3(R=Gd, Dy, and other rare-earth elements except for Eu) which synthesized by means of high pressure and high temperature, were investigated using Mossbauer spectroscopy. Owing to that the asymmetry parameter of EFG η≠0, each experimental spectrum was fitted by twelve transitional lines. The results show that the isomer shift depends on atomic number of the second rare-earth element and in linear relationship with unit-cell volume V1/3.

Investigation of thermostimulated phenomena of the dysprosium ion in yttrium–aluminium (YAG) and dysprosium-aluminium (DAG) garnet lattices

Assumptions are examined of using Dy2+ as active ion of garnet optical generators pumped by ionizing irradiation. The defective structure of YAG:Dy and DAG is investigated using thermostimulated currents and thermostimulated luminescence by different methods. The results thus obtained are discussed. Annahmen werden untersucht uber die Verwendung von Dy2+ als aktives Ion in optischen Generatoren auf Granatbasis, die mit ionisierender Strahlung gepumpt werden. Die Defektstruktur von YAG:Dy und DAG wird mit der Methode thermisch angeregter Strome und mit thermostimulierter Lumineszenz bei verschiedenen Methoden untersucht. Die so erhaltenen Ergebnisse werden diskutiert.

Effect of dysprosium oxide on the properties of nickel-zinc ferrites

Advances being made in various fields of engineering have great ly stimulated r e sea rches aiming at developing new fe r r i t e mater ia l s possess ing cer ta in desi rable combinations of magnetic and e lect r ical propert ies. In recent yea r s , a number of attempts have been made to determine the effect of alloying with oxides of the r a r e e a r t h elements on the proper t ies of fe r r i tes [1-3]. In this connection, the present work was under taken with the aim of studying the effect of dyspros ium oxide, the tr ivalent ion of which has a localized magnetic moment equal to 10.59 Bohr magnetons, on the proper t ies of 600NN, a n i cke l z inc fe r r i te extensively used in industry.

ASESORÍAS INNOVADORAS EN RECURSOS HUMANOS PARA LAS PYMES MEDIANTE EL USO DE LA RED DE INTERNET

Splicing of exons 2 and 3 of a-tropomyosin (TM) involves mutually exclusive selection of either exon 3, which occurs in most cells, or of exon 2 in smooth muscle (SM) cells. The SM-specific selection of exon 2 results from the inhibition of exon 3. At least two essential cis-acting elements are required for exon 3 inhibition, the upstream and downstream regulatory elements (URE and DRE). These elements are essential for repression of TM exon 3 in SM cells, and also mediate a low level of repression of exon 3 in an in vitro 5' splice site competition assay in HeLa extracts. Here, we show that the DRE consists of at least two discrete components, a short region containing a number of UGC motifs, and an essential pyrimidine-rich tract (DY). We show that the specific sequence of the DY element is important and that DY is able to bind to factors in HeLa nuclear extracts that mediate a low background level of exon 3 skipping. Deletion of a sequence within DY identified as an optimal binding site for PTB impairs (1) regulation of splicing in vivo, (2) skipping of exon 3 in an in vitro 5' splice site competition, (3) the ability of DY competitors to affect the 5' splice site competition in vitro, and (4) binding of PTB to DY. Addition of recombinant PTB to in vitro splicing reactions is able to partially reverse the effects of the DY competitor RNA. The data are consistent with a model for regulation of TM splicing that involves the participation of both tissue-specific and general inhibitory factors and in which PTB plays a role in repressing both splice sites of exon 3.

ESR of Dysprosium in Cubic Fields in SrF2

ESR of Dysprosium in Cubic Fields in SrF₂

Determination of cerium, gadolinium, dysprosium, erbium, and ytterbium

酸化トリウム中のセリウム,ガドリニウム,ジスプロシウム,エルビウムおよびイッテルビウムの濃度を同位体希釈法により測定した.スパイクとして電磁分離で濃縮した同位体(140Ce, 155Gd, 164Dy,167Er, 173Yb)を用いた.試料を溶解したのち,既知量のスパイクの溶液をそれぞれ加えて,希土類元素をチオシアン酸塩-TBP抽出法によりマトリックスから分離し,さらに逆相クロマトグラフィーによりランタンからユーロピウムまでとガドリニウムからルテチウムまでのグループに分離する.前者についてはセリウム,後者についてはガドリニウム,ジスプロシウム,エルビウムおよびイッテルビウムの同位体組成を表面電離型質量分析計(CEC21-702B)を用いて測定し,その結果から各元素の濃度を算出する.この方法は酸化トリウム中のppmからppbまでの濃度範囲のセリウム,ガドリニウム,ジスプロシウム,エルビウムおよびイッテルビウムの定量に満足すべき精度と正確度で適用することができた.

A New Naturally Occurring Isotope of Dysprosium

A New Naturally Occurring Isotope of Dysprosium