Neodymium

The Master's programme Industrial Ecology is jointly organised by Leiden University and Delft University of Technology. Neodymium applications, especially the neodymium-iron-boron (NdFeB) permanent magnet, have substantially enabled continuous miniaturization in the electronics sector and have become increasingly vital to electric mobility and direct-drive wind turbines. With 86% of neodymium primary production, separation and refining monopolized by China combined with its significance to the global (decarbonizing) economy, neodymium has been identified as a critical raw material across virtually every non-fuel mineral criticality assessment hitherto. Through quantifying, modeling and characterizing neodymium stocks and flows using material flow analysis (MFA) and scenario mapping, this research aims to determine the theoretical potential of the neodymium urban mine using the an assessment in the Netherlands in 2010 and 2030 as a case study. Results demonstrate the salience of ...

The Authors, after having defined the phenomenon and the biological characteristics of natural magnets, evaluate their ability in accelerating the formation of bone callus in hand and wrist fractures compared to treatment with immobilization in a plaster cast. Forty patients (4 females and 37 males) between 20 and 86 years of age were treated. A small natural magnet was inserted in each of the plaster casts (diameter: 2cm, height: 0.5cm) made of 4 blocks in Neodymium-Iron-Boron, capable of generating 4 magnetic poles (2 positive and 2 negative) of diagonal alternate polarity that produced a symmetric, quadruple static magnetic field. The created magnetic flow was wavelike, concentrated in one direction, and developed a force up to 12,500 gauss. From this study it has emerged that inserting a quadruple magnet in a plaster cast in hand and wrist fractures results in the formation of bone callus in an average time that is 35% inferior to the "standard" time. Accelerating the ...

The purpose of this study was to assess the efficacy of Nd:YAG laser irradiation in disinfecting the root canal system. Seventy-five teeth were uniformly instrumented and sterilized, and their root canals were infected for 60 min with an overnight culture of Enterococcus faecalis in Tryptic Soy Broth. The teeth were divided into 6 groups: 1--non-infected controls; 2--infected controls; 3--infected, laser treated; 4--infected, laser dummy (dye only); 5--infected, laser dummy (dye and air-water spray); 6--infected, NaOCl-treated (reference group). After treatment, the root canals were dried and dentinal shavings removed for a post-treatment culture. Quantitative analysis of bacteria surviving the various treatments were performed and the bacterial counts for each group were compared. SEM analysis of teeth split longitudinally was used to illustrate the effect of treatment on the smear layer and on surface bacteria. Nd:YAG laser irradiation (group 3) significantly reduced the number of...

Neodymium applications, especially the neodymium-iron-boron (NdFeB) permanent magnet, have substantially enabled continuous miniaturization in the electronics sector and have become increasingly vital to electric mobility and direct-drive wind turbines. With 86% of neodymium primary production, separation and refining monopolized by China combined with its significance to the global (decarbonizing) economy, neodymium has been identified as a critical raw material across virtually every non-fuel mineral criticality assessment hitherto. Through quantifying, modeling and characterizing neodymium stocks and flows using material flow analysis (MFA) and scenario mapping, this research aims to determine the theoretical potential of the neodymium urban mine using the an assessment in the Netherlands in 2010 and 2030 as a case study. Results demonstrate the salience of neodymium flows via the electronics sector in 2010 and 2030 and based on clean technology trends, the role of neodymium in the automotive and renewable energy waste streams beyond 2030.

Layered anorthosite complexes are typical components of Archean crustal domains. However, the geodynamic settings in which they were emplaced are still discussed as geological relationships are often ambiguous. Here we report major, trace element and high-precision high-field-strength-element (HFSE) data for the recently discovered well preserved Naajat Kuuat Anorthosite Complex from the inner Ameralik fjord region, southern West Greenland. The dataset is complemented by the first combined Hf–Nd isotope analyses for Archean layered anorthosite complexes and U–Pb zircon geochronology. The data contribute to the small database on Archean layered anorthosite complexes and are used to unravel the origin of these complexes and the tectonic regime involved. Fractional crystallisation of olivine, pyroxene, plagioclase and possibly amphibole controls major and trace element variations in the layered intrusion. There are two groups of amphibolites: (1) a group with primitive mantle normalized trace element patterns are similar to those of MORB-like basalts and (2) typical island-arc tholeiites (IAT), apparently indicating an island-arc setting. Lu–Hf regression lines yield an age of 2985 ± 59 Ma (MSWD 4) within the error of the Sm–Nd regression age of 2929 ± 110 Ma (MSWD 17). The initial ɛHf(2985) for the Naajat Kuuat rocks range from +1.6 to +5.8 and the initial ɛNd(2985) range from +0.4 to +3.9, either indicating variably depleted mantle sources or variable degrees of crustal contamination. In contrast to most mafic assemblages, ratios of Nb/Ta are highly variable (7.85 to 18.6), reflecting fractionation and accumulation of amphibole, ilmenite and pyroxene. The MORB-like parental liquids have the highest Nb/Ta of ca. 18, consistent with a mantle source overprinted by melt-like components from subducting oceanic crust with high Nb/Ta. The accumulation of plagioclase forming the anorthosites and the primary fractionation of amphibole as well as the occurrence of high-Al basalts within the Naajat Kuuat complex argue for hydrous parental liquids in support of an island-arc related setting. Zircon U–Pb geochronology from the anorthosite and adjacent tonalites reveal major tonalite intrusion into the complex at ca. 2802 Ma and a second regional event at ca. 2710 Ma, in accord with crustal heating due to micro-continent amalgamation and crustal thickening. Altogether, the geochemical data can be interpreted with a geodynamic model, where anorthosite-complex associated rocks intrude into tectonically thickened island-arc crust. Crustal thickening is possibly triggered by island-arc accretion, leading to the emplacement of TTG bodies that further thickened the crustal pile. Further collision and amalgamation with other proto-crustal assemblages might have led to enhanced crustal magmatism and granulite facies metamorphism.

Abstrak Tujuan dari penelitian ini adalah merancang dan membuat generator fluks aksial putaran rendah serta mengamati grafik kinerja karakteristik yang diperoleh dari output generator. Penelitian ini merupakan jenis penelitian kualitatif. Penelitian yang dilakukan memiliki fokus pada disain sketsa perancangan dan pembuatan obyek komponen generator fluks aksial. Untuk mendapatkan data primer dan data sekunder, peneliti menggunakan teknik observasi, studi pustaka, serta teknik pengukuran dan pengujian. Tingkat performa generator dengan kemampuan sebagai prototipe atau purwarupa pada hasil akhir dari penelitian ini adalah pada putaran 800 rpm dengan frekuensi rata-rata 80 Hz generator dapat membangkitkan tegangan 128 VAC dengan nilai arus 24,5 mA. Kesimpulan penelitian ini adalah generator fluks aksial multi cakram 1 fasa untuk putaran rendah dapat dirancang dengan spesifikasi 6 buah stator dan 7 keping rotor berbahan aluminium menggunakan magnet neodymium (NdFeB) sebanyak 12 kutub. Masing-masing stator terdapat 6 buah kumparan kawat tembaga dengan diameter 0,6 mm memiliki jumlah lilitan rata-rata sebanyak 100 lilitan. Nilai perbandingan dari hasil perhitungan dan pengukuran pada generator tersebut adalah 5,69 % dan dikatakan telah mendekati nilai tingkat akurasi yang baik. Pada kecepatan 250 rpm nilai tegangan ketika sebelum diberi beban adalah 36,4 VDC dan pada saat diberi beban turun menjadi 16,46 VDC. Nilai faktor regulasi tegangan DC generator tersebut adalah 54,81 %. Drop voltage tersebut disebabkan karena generator tidak dilengkapi perangkat stabilizer tegangan. Kata Kunci: Generator Fluks Aksial, 1Fasa, Multi Cakram, Neodymium Magnet (NdFeB).

Nonablative laser resurfacing has been shown to improve the appearance photoaged skin. Clinical improvement has been associated with dermal collagen remodeling. The objective was to determine the efficacy of a 1320-nm Nd:YAG laser for the treatment of photoaging hands. Seven patients with photoaged hands received six monthly treatments with a 1320-nm Nd:YAG laser. Improvement in skin smoothness was evaluated by objective and patient assessment using a 6-point improvement scale: 1=no improvement and 6=80% to 100% improvement. Mild to moderate improvement was achieved as determined by both objective and patient assessment. Mean improvement by objective assessment was 2.4 points. Objective improvement was noted in four of seven patients, and these patients demonstrated a mean improvement score of 3.5 points. The mean improvement by patient assessment was 3.1 points. This case series demonstrates that the 1320-nm Nd:YAG laser with cryogen cooling can be effective for rejuvenation of photoaged hands.

We have performed a density functional calculation for the centrosymmetric neodymium gallate using a full-potential linear augmented plane wave method with the LDA and LDA+U exchange correlation. In particular, we explored the influence of U on the band dispersion and optical transitions. Our calculations show that U = 0.55 Ry gives the best agreement with our ellipsometry data taken in the VUV spectral range with a synchrotron source. Our LDA+U (U = 0.55) calculation shows that the valence band maximum (VBM) is located at T and the conduction band minimum (CBM) is located at the center of the Brillouin zone, resulting in a wide indirect energy band gap of about 3.8 eV in excellent agreement with our experiment. The partial density of states show that the upper valence band originates predominantly from Nd-f and O-p states, with a small admixture of Nd-s/p and Ga-p B-p states, while the lower conduction band prevailingly originates from the Nd-f and Nd-d terms with a small contribution of O-p-Ga-s/p states. The Nd-f states in the upper valence band and lower conduction band have a significant influence on the energy band gap dispersion which is illustrated by our calculations. The calculated frequency dependent optical properties show a small positive uniaxial anisotropy.

Dramatic changes from a cold and dry last glacial to a warm and wet Holocene period intensified the Indian summer monsoon
(ISM), resulting in vigorous hydrology and increased terrestrial erosion. Here we present seawater neodymium (Nd) data
(expressed in εNd) from Andaman Sea sediments to assess past changes in the ISM and the related impact of Irrawaddy–
Salween and Sittoung (ISS) river discharge into the Andaman Sea in the northeastern Indian Ocean. Four major isotopic
changes were identified: (1) a gradual increase in εNd toward a more radiogenic signature during the Last Glacial Maximum
(22–18 ka), suggesting a gradual decrease in the ISS discharge; (2) a relatively stable radiogenic seawater εNd between 17.2
and 8.8 ka, perhaps related to a stable reduced outflow; (3) a rapid transition to less radiogenic εNd signature after 8.8 ka,
reflecting a very wet early–mid-Holocene with the highest discharge; and (4) a decrease in εNd signal stability in the mid–late
Holocene. Taking into account the contribution of the ISS rivers to the Andaman Sea εNd signature that changes proportionally
with the strengthening (less radiogenic εNd) or weakening (more radiogenic εNd) of the ISM, we propose a binary model
mixing between the Salween and Irrawaddy rivers to explain the εNd variability in Andaman Sea sediments. We hypothesize
that the Irrawaddy river mainly contributed detrital sediment to the northeastern Andaman Sea for the past 24 ka. Our εNd
data shed new light on the regional changes in Indo-Asian monsoon systems when compared with the existing Indian and
Chinese paleo-proxy records.

Pr and Nd co-doped Ce-Zr oxide solid solutions (CZPN) were prepared using co-precipitation and microemulsion methods. It is found that only using supercritical CO(2) drying can result in a significant improvement of specific surface area and oxygen storage capacity at lower temperatures for CZPN after aging at 1000°C for 12 h in comparison with those using conventional air drying and even supercritical ethanol drying. Furthermore, the cubic structure was obtained in spite of the fact that the atomic ratio of Ce/(Ce+Zr+Pr+Nd) is as low as 29%. The high thermal stability can be attributed to the loosely aggregated morphology and the resultant Ce enrichment on the nanoparticle surface, which are caused by supercritical CO(2) drying due to the elimination of surface tension effects on the gas-liquid interface.

Cerium (III), lanthanum (III) and neodymium (III) complexes with 3,3'-benzylidenebis[4-hydroxycoumarin] were synthesized in view of their application as cytotoxic agents. The complexes were characterized by different physicochemical methods: elemental analysis, mass spectrometry, 1H NMR, 13C NMR and IR spectroscopy. The spectra of the complexes were interpreted on the basis of comparison with the spectrum of the free ligand. The vibrational analysis showed that in the complexes the ligand coordinated to the metal ion through both deprotonated hydroxyl groups; however, participation of the carbonyl groups in the coordination to the metal ion was also suggested. The evaluation of the cytotoxic activity of the novel lanthanide complexes on HL-60 myeloid cells revealed that they are potent cytotoxic agents. The cerium complex was found to exhibit superior activity in comparison to the lanthanum and neodymium coordination compounds, the latter being the least active. Our data give us reason to conclude that the newly synthesized lanthanide complexes should be submitted to further more detailed pharmacological and toxicological evaluation.

We report the case of a 46-year-old Caucasian female presenting with mucocutaneous pigmentation on the lips, oral mucosa, hands, feet and nails, as well as on a psoriatic plaque. She was successfully treated with Q-switched Nd-Yag laser, with double frequency, for both the mucosal and cutaneous lesions.

ILs based on the bis(trifluoromethylsulfonyl)imide anion ((CF3SO2)2N-, noted TFSI-) have recently gained a growing of interest because of their hydrophobic character, their superior chemical and thermal stability, their low viscosity, low melting point, high conductivity and high radiolytic stability. All of these criteria are very important for electrodeposition of actinides and lanthanides, known to be very electropositive elements. These TFSI - based ILs have then been selected to study the electrodeposition of neodymium and lanthanum. The work has been focused on the Nd(TFSI)3 and La(TFSI)3 salts, which are very water sensitive. Moreover, the redox properties of both ILs and metallic salts depend on the water content. All experiments have then been carried out in an argon – filled dry box (H2O < 10 ppm ; O2 < 1 ppm).

The Nd:YAG laser can be used in Dentistry to remove soft tissue, disinfect canals in endodontic procedures and prevent caries. However, there is no protocol for Nd:YAG laser application in dental bleaching. The aims of this in vitro study were: (a) to observe the tooth shade alteration when hydrogen peroxide whitening procedures are associated with dyes with different wavelengths and irradiated with Nd:YAG laser or halogen light; (b) to measure the Vickers (VHN) enamel microhardness before and after the whitening procedure; (c) to evaluate the tensile bond strength of two types of adhesive systems applied on bleached enamel; (d) to observe the failure pattern after bond strength testing; (e) to evaluate the pulpal temperature during the bleaching procedures with halogen light or laser; (f) to measure the kinetic reaction of hydrogen peroxide. Extracted sound human molar crowns were sectioned in the mesiodistal direction to obtain 150 fragments that were divided into five groups for each adhesive system: WL (H(2)O(2) + thickener and Nd:YAG), WH (H(2)O(2) + thickener and halogen light), QL (H(2)O(2) + carbopol + Q-switch and Nd:YAG), QH (H(2)O(2) + carbopol + Q-switch and halogen light), and C (Control, without whitening agent). Shade assessment was made with a shade guide and the microhardness tests were performed before and after the bleaching procedures. Immediately afterwards, the groups were restored with the adhesive systems Adper Single Bond 2 or Solobond M plus composite resin, and the tensile bond strength test was performed. The temperature was measured by thermocouples placed on the enamel surface and intrapulpal chamber. The kinetics of hydrogen peroxide was observed by ultraviolet analysis. The shade changed seven levels for Nd:YAG laser groups and eight levels for halogen light. According to the student&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;#39;s t-test, there was no statistical difference between the VHN before and after the whitening protocols (p &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;gt; 0.05). The tensile bond strength showed no statistical significance between the test groups and the controls, considering both adhesive systems tested by ANOVA and Tukey tests (p &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;gt; 0.05). The predominant failure pattern after bond strength testing was mixed. The temperature was safe for laser and halogen light. The kinetic reaction showed that after 5 min all the hydrogen peroxide had been consumed. Nd:YAG laser associated with hydrogen peroxide bleached the enamel, the shade being similar to that obtained with the traditional method performed with halogen light. Moreover, the Vickers&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;#39; microhardness and bond strength values were not altered in comparison with those for nonbleached enamel.

Isotopic characterization of aerosol mineral particles (atmospheric dust) of varying sizes is essential in
classifying source areas, and for determining the source of dust deposited over oceans and icesheets. However,
the effect of atmospheric transport on radiogenic isotopic compositions is not well constrained, making
provenance interpretation difficult. In order to investigate the isotopic variability of 176Hf/177Hf, 87Sr/86Sr and
143Nd/144Nd we analyzed eight airborne dust samples in two size fractions collected along a cross-Atlantic
transect through a dust storm originating in the Sahara in late 2002. Past measurements of 176Hf/177Hf, 87Sr/86Sr
and 143Nd/144Nd of dust have focused primarily on coarse sized particles (b30 μm), whereas far field deposition
is primarily finer particles (b2 μm). Strontium or neodymium isotopic sorting based on distance is not evident
in our dataset; however, the combined isotopic ratios of the dust collected suggest a Saharan origin. Hafnium
isotopic compositions show an east to west trend towards more radiogenic compositions across the Atlantic,
suggesting grain and mineral sorting during dust transport along the ~4000 km transect. Transport models
with variable dust particle diameter and wind speed demonstrate the preferential depletion of the highdensity
mineral zircon during transport of dust from the source area. The transport model combined with a
simple two component mixing model show that the Hf isotopic composition changes can be explained by the
loss of the mineral zircon during transport. Modeling of this “zircon effect” with distance from the dust source
in the Hf isotopic composition of marine, terrestrial and glacial dust deposits may reveal additional information
concerning dust transport and sources in the geologic past.

Since the development of the ruby laser by Maiman in 1960 and the application of the laser for endodontics by Weichman in 1971, a variety of lasers with a wide range of characteristics are now being used in endodontic therapy. In the past two decades much experience and knowledge has been gained The first purpose of the present paper is to provide an understanding of the essential physical science behind laser technology and information on the effects of laser beams on tissue (tissue interaction). A second purpose is to summarize laser applications in endodontics, including their use in pulp diagnosis, dentinal hypersensitivity, pulp capping and pulpotomy, modification of the root canal walls, sterilization of the root canal system, cleaning--shaping--obturation of the root canal, and endodontic surgery. It will be clear that a number of endodontic procedures with conventional treatments cannot provide comparable results or are less effective.

Open-field aluminum-nickle-cobalt magnets have been used in prosthodontics for many years, but success has been limited because these magnets are susceptible to corrosion by the saliva and because their retentive force is weak relative to the initial retention offered by mechanical attachments. More recently, magnets have been made from alloys of the rare earth elements samarium and neodymium, which provide stronger magnetic force per unit size. In addition, a new generation of laser-welded containers has improved protection from salivary corrosion. The current resurgence of interest in this type of attachment appears justified because, unlike mechanical attachments, magnets have potential for unlimited durability and might therefore be superior to mechanical ball or bar attachments for the retention of removable prostheses on implants. To date, no long-term prospective trials have been conducted to confirm the clinical durability of this new generation of magnets for retaining dentures on either teeth or implants. The aim of this study was to document initial clinical experiences and levels of satisfaction among edentulous patients treated with mandibular implant-supported overdentures retained using a new generation of rare-earth magnetic attachments. At the outset, all but one of the 17 patients had had several years of experience with implant-supported overdentures. During the first year, the mean overall satisfaction among these 17 patients increased from less than 70 to over 90 out of 100 (standardized visual analogue scale). No unusual difficulties were encountered in rendering the treatment or maintaining the attachments. This report offers preliminary evidence of the excellent potential of these magnets for retaining mandibular implant-supported overdentures.

Chromophore dyes can be employed to modify laser-tissue interaction. A number of dyes have been investigated for their effect on the absorption and transmission of argon and Nd:YAG laser energy by vascular tissue in vitro. Three histological dyes have been assessed as potential chromophores for the argon laser and four infrared dyes for the Nd:YAG. Segments of porcine coronary artery to which dye had been applied were lased (1,064 nm, 2.5 W, 83 W/cm2, 60 s and 488/514 nm, 400 mW, 10.5 W/cm2, 60s) and the tissue temperature measured remotely using an infrared thermometer. In addition, energy transmission was measured with a photodiode and tissue morphological changes assessed histologically.All three argon dyes significantly increased energy absorption (typically 60°C v. 20°C at 60 s, P < 0.001, 2-way ANOVA). Three of the four infrared dyes behaved similarly (40–70°C v. 20°C, P < 0.001). All dyes significantly increased the initial rate of rise in tissue temperature during lasing. A reduction in energy transmission was observed for each of the Argon dyes but not for the Nd:YAG dyes. Histological evidence of thermal damage in control tissue first occurred for the argon and Nd:YAG lasers at 800 mW and 7.5 W without chromophore and at 400 mW and 2.5 W with the chromophore, respectively.A number of effective chromophores have therefore been identified at each wavelength. © 1992 Wiley-Liss, Inc.

Chromophore dyes can be employed to modify laser-tissue interaction. A number of dyes have been investigated for their effect on the absorption and transmission of argon and Nd:YAG laser energy by vascular tissue in vitro. Three histological dyes have been assessed as potential chromophores for the argon laser and four infrared dyes for the Nd:YAG. Segments of porcine coronary artery to which dye had been applied were lased (1,064 nm, 2.5 W, 83 W/cm2, 60 s and 488/514 nm, 400 mW, 10.5 W/cm2, 60s) and the tissue temperature measured remotely using an infrared thermometer. In addition, energy transmission was measured with a photodiode and tissue morphological changes assessed histologically.All three argon dyes significantly increased energy absorption (typically 60°C v. 20°C at 60 s, P < 0.001, 2-way ANOVA). Three of the four infrared dyes behaved similarly (40–70°C v. 20°C, P < 0.001). All dyes significantly increased the initial rate of rise in tissue temperature during lasing. A reduction in energy transmission was observed for each of the Argon dyes but not for the Nd:YAG dyes. Histological evidence of thermal damage in control tissue first occurred for the argon and Nd:YAG lasers at 800 mW and 7.5 W without chromophore and at 400 mW and 2.5 W with the chromophore, respectively.A number of effective chromophores have therefore been identified at each wavelength. © 1992 Wiley-Liss, Inc.

Two novel mononuclear neodymium alkoxides [Nd{OC-(C 14 H 11 S 2 )} 3 (thf) 3 ]·thf (9) and [Nd{OC(C 16 H 13 S)} 3 (thf) 3 ]·thf (10) have been prepared by the reaction between Nd[N(SiMe 3 ) 2 ] 3 and the tertiary alcohols HO-C(C 14 H 11 S 2 ) (3) and HO-C(C 16 H 13 S) (4). The geometry around the neodymium metal is almost octahedral with a facial ligand arrangement similar to [Nd{OC(C 8 H 5 S 2 ) 3 } 3 (thf) 3 ]·4thf (5), [Nd(OC-(C 4 H 3 S) 3 } 3 (thf) 3 ]·thf (7) and Er[OC(C 4 H 3 S) 3 ] 3 (thf) 3 (8) (X-ray diffraction on single crystals). The cyclic voltammograms of a series of neodymium and erbium alkoxides indicate that the electrochemical properties are essentially dominated by the organic ligands. In comparison to the carbinols HOC(C 8 H 5 S 2 ) 3 (1), HO-C(C 4 H 3 S) 3 (2), HO-C(C 14 H 11 S 2 ) (3) or HO-C(C 16 H 13 S) (4), the oxidation peak potentials of the thienyl units for the neodymium alkoxides [Nd{OC(C 8 H 5 S 2 ) 3 } 3 -(thf) 3 ]·4thf (5), [Nd{OC(C 4 H 3 S) 3 } 3 (thf) 3 ]·thf (7), [Nd{OC-(C 14 H 11 S z )} 3 (thf) 3 ]·thf (9) and [Nd{OC(C 16 H 13 S)} 3 (thf) 3 ]·thf (10) are marginally shifted towards higher values by 0.03-0.10V, whereas for Er[OC(C 8 H 5 S 2 ) 3 ] 3 (thf) (6) and Er-[OC(C 4 H 3 S) 3 ] 3 (thf) 3 (8) a decrease of these potentials is noticed. Repetitive cyclic voltammetry does not generate polymeric films for 7-10, as found for the free organic ligands 2-4. Contrarily, the mononuclear precursors [Nd{OC(C 8 H 5 S 2 ) 3 } 3 -(thf) 3 ]·4thf (5) and Er[OC(C 8 H 5 S 2 ) 3 ] 3 (thf) (6) are electro-oxidized and electro-active polymer films are obtained and characterized. To investigate the positions of the excited states of the ligands, emission spectra of the carbinols 1-4 have been recorded. The luminescence studies of the neodymium alkoxides reveal an energy transfer from the ligand to the metal centre with a remarkable Nd emission efficiency upon ligand excitation in the case of 5.

In this study analysis of major elements and Sr-Nd isotopes is performed on 33 colourless glass fragments from two Roman shipwrecks discovered in the Northern Mediterranean Sea, the Julia Felix (first half of the third century AD) and the Ouest-Embiez (end of the second beginning of the third century AD). Two compositional groups are defined based upon the major elements analysis, suggesting the use of different raw materials, and possibly the production of the glass samples in two separate factories. Sr-Nd isotopes, promising indicators for provenancing geological resources used as raw materials in glass manufacturing, confirm the compositional groups. The Sr-87/Sr-86 signature is very close to the modern sea water signature (0.7092) for all samples, likely due to the use of shell as glass raw material. The Nd signature further subdivides the compositional groups, suggesting the use of three different sand raw materials for the production of glass.