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1.
Artigo em Inglês | MEDLINE | ID: mdl-39229749

RESUMO

Research concerning coordination polymers has been intense due to their significant variability and structural stability. With this in mind, an ionic neodymium coordination polymer was synthesized, composed of an anionic one-dimensional polymer interconnected to a cationic three-dimensional porous polymer, poly[dodecaaquabis(µ-pyridine-4-carbohydrazide-κ2N:O)bis(µ2-4-sulfobenzoato-κ2O:O')bis(µ3-4-sulfobenzoato-κ3O:O':O'')trineodymium(III)] catena-poly[aquabis(µ-pyridine-4-carbohydrazide-κ2N:O)bis(µ2-4-sulfobenzoato-κ2O:O')neodymium(III)] 4.33-hydrate, {[Nd3(C7H4O5S)4(C6H7N3O)2(H2O)12][Nd(C7H4O5S)2(C6H7N3O)2(H2O)]·4.33H2O}n. The ligands used were 4-sulfobenzoate (PSB) and pyridine-4-carbohydrazide, popularly known as isoniazid (INH), an antibiotic drug. The compound crystallizes in the monoclinic space group C2/c, with Z = 4. Solid-state calculations suggest that the crystal structure is mainly stabilized by hydrogen bonds, i.e. O-H...O and N-H...O interactions among the polymers, and by van der Waals interactions involving the organic side chains. This net is tetragonal, 2-nodal 3,4-connected, and can be described as the dmd (sqc 528) type.

2.
Small ; : e2401964, 2024 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-39162112

RESUMO

Exploring efficacious low-Ir electrocatalysts for oxygen evolution reaction (OER) is crucial for large-scale application of proton exchange membrane water electrolysis (PEMWE). Herein, an efficient non-precious lanthanide-metal-doped IrO2 electrocatalyst is presented for OER catalysis by doping large-ionic-radius Nd into IrO2 crystal. The doped Nd breaks the long-ranged order structure by triggering the strain effect and thus inducing an atomic rearrangement of Nd─IrO2 involving the forming of Nd─O─Ir bonds along with an increased amount of oxygen vacancies (Ov), giving rise of a long-ranged disorder but a short-ranged order structure. The formed Nd─O─Ir bonds tailor the electronic structure of Ir, leading to a lowered d-band center that weakens intermediates absorption on Ir sites. Moreover, doping Nd triggers Nd─IrO2 to catalyze OER mainly through lattice oxygen mechanism (LOM) by activating lattice oxygen owing to abundant Ov. The optimal catalyst only requires a relatively low overpotential of 263 mV@10 mA cm-2 with a high mass activity of 216.98 A gIr -1 (at 1.53 V) (eightfold of commercial IrO2), and also shows a superior durability at 50 mA cm-2 (20 h) than commercial IrO2 (3 h) due to the oxidation-suppressing effect induced by Nd doping. This work offers insights into designing high-performance low-Ir electrocatalysts for PEMWE application.

3.
J Lasers Med Sci ; 15: e24, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39188929

RESUMO

Introduction: Facial partial unilateral lentiginosis (PUL) is an infrequent skin pigmentation disorder characterized by multiple lentigines. Despite the availability of various treatment modalities, there is no standard treatment for PUL. This study reports a successful treatment of facial PUL in a female patient using a novel 532-nm Nd:YAG fractional picosecond laser (FPL). Case Report: The patient underwent four treatment sessions at four-week intervals. The treatments were administered using a 9 mm high coverage handpiece micro lens array (MLA), with a fluence of 0.2-0.4 J/cm2, a frequency of 2 Hz for 2-3 passes, and approximately 10% overlap. The treatment was well-tolerated by the patient, with significant improvement in pigmentation and no significant side effects observed. The outcomes confirmed the efficacy of the 532-nm Nd:YAG FPL in treating facial PUL. Conclusion: The 532-nm Nd:YAG FPL appears to be an effective and well-tolerated treatment for facial PUL, offering significant improvement in pigmentation without notable side effects.

4.
Heliyon ; 10(12): e33006, 2024 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-39022042

RESUMO

We compared the posterior capsule opacification incidences at 5 years postoperatively and the neodymium-yttrium-aluminum-garnet capsulotomy rates at 10 years postoperatively for two types of intraocular lenses with different optical properties and shapes. This randomized, controlled, prospective, single-blinded study with intra-individual comparisons was conducted between July 21, 2009, and August 31, 2011, at the Dokkyo Medical University Hospital, Tochigi, Japan. Thirty patients (60 eyes) underwent bilateral cataract surgery and received a XY1 intraocular lens in one eye and a FY-60AD intraocular lens in the other. Both intraocular lenses are acrylic and manufactured by HOYA. The XY1 lens is a single-piece, tinted intraocular lens featuring an ultraviolet/ozone treatment on the posterior surface of the lens optic, aimed at enhancing posterior capsule adhesion to prevent posterior capsule opacification. Conversely, the FY-60AD is a tinted intraocular lens with modified polymethylmethacrylate C-loops and no ultraviolet/ozone treatment of the optic. Scheimpflug images were taken using EAS-1000 (NIDEK Co., Ltd., Aichi, Japan), and the scattered light intensity (computer compatible tape) on the posterior surface of the intraocular lens was calculated and evaluated as the posterior capsule opacification. The scattered light values of the XY1 and FY-60AD groups were 6.50 ± 5.69 and 11.64 ± 5.30 computer compatible tape, respectively, at 5 years postoperatively. The cumulative survival incidence after neodymium-yttrium-aluminum-garnet laser capsulotomy was 74.8 % in the XY1 group and 13.8 % in the FY-60AD group at 10 years postoperatively. The surface-modified intraocular lens XY1 reduced the incidence of posterior capsule opacification even 10 years after surgery. Surface modification to increase the adhesion between the intraocular lens and the capsule effectively prevents posterior capsule opacification.

5.
Cureus ; 16(6): e63370, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-39070462

RESUMO

A 71-year-old, one-eyed female patient presented with a loss of vision in the right eye due to trauma 20 years ago and a progressive diminution of vision in the left eye over the past six years. An ambiguous history of some surgery performed on the left eye was elicited, with no available records, adding an element of uncertainty to this case. Visual acuity (VA) was noted as no light perception (No PL) in the right eye and light perception with accurate projection of rays (PL+, PR accurate) in the left eye. Anterior segment slit-lamp evaluation of the right eye showed a shrunken globe with low intraocular pressure (IOP). The left eye exhibited signs of chronic uveitis with occlusio pupillae, non-visualization of the lens, and a doubtful conjunctival bleb with scleral thinning superior to the limbus. B-scan evaluation was suggestive of phthisis in the right eye and an equivocal lens shadow in the left eye. A yttrium aluminum garnet (YAG) pupillary membranotomy was planned for the left eye under steroid cover and was cautiously attempted, successfully detaching the occlusio membrane and revealing an underlying complicated cataract beneath it. Post-laser, medical management included topical anti-glaucoma and steroid medications, along with systemic steroids. The VA improved from PL+, PR accurate to 3/60 (improving to 6/60 with a Retinal Acuity Meter). After stabilization of the uveitis over the next few weeks and under a steroid cover, a temporal clear-corneal phacoemulsification was cautiously performed with intra-operative management of the small pupil, and a hydrophobic lens was implanted. At one month post-surgery, the patient's best-corrected visual acuity had improved to 6/12 for distance and N6 for near. This report highlights a compelling instance wherein the neodymium:Yttrium-aluminum-garnet (Nd:YAG) laser was efficaciously employed for a lesser-known application in resolving a diagnostic dilemma and for instituting an interim treatment strategy in a challenging case involving a one-eyed patient prior to planning a definitive surgery. This case emphasizes the importance of thinking out of the box, ensuring comprehensive preoperative and careful intra-operative precautions in the management of patients diagnosed with complex ocular inflammatory conditions, so as to optimize visual outcomes, eventually resulting in achieving a gratifying reduction of visual disability and improvement of quality of life.

6.
Int Med Case Rep J ; 17: 683-693, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39071183

RESUMO

Posterior capsular opacification (PCO), also known as "secondary cataract", is a common complication following cataract surgery that can significantly impair visual acuity. The incidence of PCO varies widely in the literature, influenced by intraocular lens (IOL) type and patient risk factors. Neodymium-doped yttrium-aluminum-garnet (YAG) laser posterior capsulotomy is the standard treatment for PCO-related visual impairment. Recurrence of PCO after initial treatment with YAG capsulotomy, though more common in children, is rare in adults. Its underlying pathophysiological mechanisms are similar to that of primary PCO, which includes proliferation, migration, and/or clustering of lens epithelial cells (LECs), with subsequent reclosure of the posterior aperture. Potential risk factors for PCO recurrence that have been speculated through a comprehensive search of the current literature include younger age, female sex, high myopia, diabetes, vitrectomized status, uveitis, low-diopter IOLs, and certain IOL types with higher water content. We present a case of recurrent PCO in a highly myopic 48-year-old male following cataract surgery and implantable collamer lens (ICL) explantation who received a hydrophobic acrylic lens with 4% water content. Surgical techniques that may reduce recurrent PCO occurrence and appropriate postoperative care are emphasized to assist surgeons in their approach to patients at high-risk for this complication.

7.
Luminescence ; 39(7): e4832, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-39031322

RESUMO

The aim of this research is to investigate novel compositions of oxyfluoride glasses doped with Neodymium (Nd3+) rare earth ions in the visible spectrum. This area has not been extensively studied in the existing literature, so it is vital to understand the favorable photoluminescence characteristics within this part of the electromagnetic spectrum. Therefore, we synthesized and characterized SiO2-PbO-PbF2 (SPF) doped with 1% neodymium (Nd3+) ions glasses. Spectroscopic analyses, based on Judd-Ofelt theory, were conducted on absorption spectra. These analyses enabled to determine absorption cross-sections, transition probabilities, and Judd-Ofelt intensity parameters Ω2, Ω4, and Ω6 for the different transition. Additionally, we calculated various radiative properties, such as branching ratios, integrated cross-sections, radiative lifetimes, emission cross-section, optical gain, and the multicolor behavior (chromaticity coordinates, CIE diagram) under different excitation wavelengths. The results suggest promising prospects for using these oxyfluoride silicate glasses doped with Nd3+ as a fluorophore, potentially for lasing materials around 630-nm emission and in other photonic applications.


Assuntos
Vidro , Neodímio , Silicatos , Dióxido de Silício , Neodímio/química , Vidro/química , Silicatos/química , Dióxido de Silício/química , Fluoretos/química , Chumbo/química , Óxidos/química , Fenômenos Ópticos , Luminescência , Cor
8.
Lasers Med Sci ; 39(1): 167, 2024 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-38954050

RESUMO

Nowadays, lasers are used in various medical fields. Ophthalmology was the first medical specialty to utilize lasers in patient treatment and still remains the leading medical field that uses laser energy for both therapeutic and diagnostic purposes. The neodymium: yttrium-aluminum-garnet (Nd: YAG) laser is one of the most common lasers used in ophthalmology. It is a solid-state laser with a wavelength of 1064 nm that works on the principle of photodisruption. Since its introduction in ophthalmology over 40 years ago, it has found various applications, mainly for procedures where cutting or disruption of ocular tissue is required. Compared to surgical alternatives, the use of Nd: YAG lasers on ocular tissue is minimally invasive. In this review, we focus on the two most common ophthalmic applications of Nd: YAG laser - laser peripheral iridotomy and posterior capsulotomy. The history of the techniques, current trends, potential complications, and the prognosis for future use is discussed.


Assuntos
Lasers de Estado Sólido , Humanos , Lasers de Estado Sólido/uso terapêutico , Terapia a Laser/métodos , Terapia a Laser/instrumentação , Capsulotomia Posterior/métodos , Iridectomia/métodos , Oftalmologia , Iris/cirurgia
9.
J Fluoresc ; 2024 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-38954085

RESUMO

In the present study, the synthesis of BaSrSiO4 co-doped Yb3+ and Nd3+ nanophosphors (NPs) was successfully achieved through the conventional sol-gel method, as confirmed by X-ray diffraction and SEM analysis, verifying the formation of pure NPs. The FTIR and Raman spectra analysis confirm the formation of silicates, as different modes and vibrations of Si-O and Si-O-Si were seen at 800-1000 cm-1. The energy transfer (ET) mechanism between Nd3+ and Yb3+ ions was seen as the emission spectra showed a rise in intensity of one over another. PLE emission spectra showed transitions at 2F7/2-2F5/2 for Yb3+ and from 4F3/2 to (4I9/2, 4I11/2, and 4I13/2) for Nd3+ when excited at 785 nm. All the samples record low activation energy, which shows that the rate of reaction will be higher in all the samples, and it will be highest for 1 mol% Nd3+ and 1 mol% Yb3+. An increasing value of τ was seen with increasing Yb3+ concentration, which confirms the increase in the population of trap centers. The positron annihilation lifetime (PAL) curve showed that 1 mol% Yb3+ and 2 mol Nd3+ have single vacancies or shallower positron traps, whereas 3 mol% Yb3+ and 2 mol% Nd3+ have larger defects like surface oxygen vacancy clusters. The other two samples have balance vacancies, which makes them best for thermometry applications. The fluorescence intensity ratio (FIR) was calculated to get sensitivity for thermometry application. 2.13% K-1 sensitivity achieved at 303-333 K temperature.

10.
Environ Pollut ; 358: 124527, 2024 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-38992831

RESUMO

Neodymium oxide (Nd2O3) is a rare earth element that can lead to various type of tissue and organ damage with prolonged exposure. The long noncoding RNA small nucleolar ribonucleic acid host gene 5 (lncRNA SNHG5) plays a role in disease progressiong. However, its connection with Nd2O3 induced reproductive harm in males has not been thoroughly investigated. Our research discovered that exposure to Nd2O3 increases the expression of SNHG5 in the testes of mice, which in turn binds directly to and reduces in the protein levels of insulin like growth factor 2 mRNA-binding protein 1 (IGF2BP1) both in vivo and in vitro. This process disrupts the cytoskeleton of blood-testis barrier(BTB) by impacting the stability of the tight junction protein Occludin (Ocln) mRNA structure and the permeability of the BTB. In summary, our study elucidates the regulatory mechanism of SNHG5/IGF2BP1/Occludin axis in Nd2O3-induced BTB injury, providing valuable insights for the treatment of male infertility.


Assuntos
Barreira Hematotesticular , Ocludina , RNA Longo não Codificante , Animais , Masculino , Camundongos , Barreira Hematotesticular/metabolismo , Ocludina/genética , Ocludina/metabolismo , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo , Proteínas de Ligação a RNA/metabolismo , Proteínas de Ligação a RNA/genética , Testículo/metabolismo
11.
Cureus ; 16(6): e63036, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-39050360

RESUMO

This case report describes the successful treatment of refractory vesicourethral anastomosis (VUA) pain in an 82-year-old man following radical prostatectomy using a combination of non-ablative erbium:YAG and neodymium:YAG laser therapy with Fotona SP Dynamis. Despite various conventional treatments, the patient's pain persisted, which significantly impaired his quality of life. The rationale for using laser therapy is based on its potential to promote tissue healing and nerve regeneration and reduce inflammation at the anastomosis site. The patient underwent monthly laser irradiation sessions, with the erbium:YAG laser targeting the area around the urethral anastomosis site via the anus and the neodymium:YAG laser irradiating the base of the penis and scrotum. Urethral pain gradually decreased from a visual analog scale score of 10 to 0 over the course of treatment. This highlights the importance of considering alternative approaches when conventional methods fail to provide relief. The targeted, minimally invasive nature of laser therapy may offer a safer and more effective alternative to systemic medications for managing chronic post-surgical pain. Although further research is needed to establish the generalizability and long-term effectiveness of this approach, this case provides a promising foundation for future investigations of the role of laser therapy in managing refractory VUA pain following radical prostatectomy.

12.
Materials (Basel) ; 17(14)2024 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-39063724

RESUMO

Composite plates comprising a blend of rare earth neodymium-(Nd) doped M-type barium ferrite (BaM) with CNTs (carbon nanotubes) and polyethylene WERE synthesized through a self-propagating reaction and hot-pressing treatment. The plates' microscopic characteristics were analyzed utilizing X-ray diffraction (XRD), Fourier transform infrared spectrophotometry (FTIR), thermo-gravimetric analysis (TGA), Raman, and scanning electron microscopy (SEM) analytical techniques. Their microwave absorption performance within the frequency range of 8.2 to 18 GHz was assessed using a vector network analyzer. It showed that CNTs formed a conductive network on the surface of the Nd-BaM absorber, significantly enhancing absorption performance and widening the absorption bandwidth. Furthermore, dielectric polarization relaxation was investigated using the Debye theory, analyzing the Cole-Cole semicircle. It was observed that the sample exhibiting the best absorbing performance displayed the most semicircles, indicating that the dielectric polarization relaxation phenomenon can increase the dielectric relaxation loss of the sample. These findings provide valuable data support for the lightweight preparation of BaM-based absorbing materials.

13.
ACS Appl Mater Interfaces ; 16(27): 35484-35493, 2024 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-38934218

RESUMO

Noncontact optical nanothermometers operating within the biological transparency windows are required to study temperature-sensitive biological phenomena at the nanoscale. Nanoparticles containing rare-earth ions such as Nd3+ have been reported to be efficient luminescence-based ratiometric thermometers, however often limited by poor water solubility and concentration-related quenching effects. Herein, we introduce a new type of nanothermometer, obtained by employing low-dimensional carbon nanodots (CNDs) as matrices to host Nd3+ ions (NdCNDs). By means of a one-pot procedure, small (∼7-12 nm), water-soluble nanoparticles were obtained, with high (15 wt %) Nd3+ loading. This stable metal-CND system features temperature-dependent photoluminescence in the second biological window (BW II) upon irradiation at 808 nm, thereby allowing accurate and reversible (heating/cooling) temperature measurements with good sensitivity and thermal resolution. The system possesses remarkable biocompatibility in vitro and promising performance at a high penetration depth in tissue models.

14.
J Chromatogr A ; 1729: 465033, 2024 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-38852269

RESUMO

Efficient rare earth element (REE) separations are becoming increasingly important to technologies ranging from renewable energy and high-performance magnets to applied radioisotope separations. These separations are made challenging by the extremely similar chemical and physical characteristics of the individual elements, which almost always occupy the 3+ oxidation state under ambient conditions. Herein, we discuss the development of a novel REE separation aimed at obtaining purified samples of neodymium (Nd) on a multi-milligram scale using high-speed counter-current chromatography (HSCCC). The method takes advantage of the subtle differences in ionic radii between neighboring REEs to tune elution rates in dilute acid through implementation of the di-(2-ethylhexyl)phosphoric acid (HDEHP)-infused stationary phase (SP) of the column. A La/Ce/Nd/Sm separation was demonstrated at a significantly higher metal loading than previously accomplished by HSCCC (15 mg, RNd/REE > 0.85), while the Pr/Nd separation was achieved at lower metal loadings (0.3 mg, RNd/Pr = 0.75 - 0.83). The challenges associated with scaling REE separations via HSCCC are presented and discussed within.


Assuntos
Distribuição Contracorrente , Neodímio , Distribuição Contracorrente/métodos , Neodímio/química , Neodímio/isolamento & purificação , Organofosfatos
15.
Front Chem ; 12: 1259032, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38690011

RESUMO

In this study, we report the synthesis of a new cubic neodymium-rhenium metallic alloy NdRe2 through the utilization of high pressure and laser heating in a diamond anvil cell. NdRe2 crystallizes in the Fd3¯m space group with a lattice parameter equal to 7.486 (2) Å and Z = 8 at 24 (1) GPa and 2,200 (100) K. It was studied using high-pressure single-crystal X-ray diffraction. The compound crystallizes in the cubic MgCu2 structure type. Its successful synthesis further proves that high-pressure high-temperature conditions can be used to obtain alloys holding a Laves phase structure. Ab initio calculations were done to predict the mechanical properties of the material. We also discuss the usage of extreme conditions to synthesize and study materials present in the nuclear waste.

16.
J Conserv Dent Endod ; 27(4): 378-382, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38779207

RESUMO

Background: The world of esthetic dentistry is constantly making efforts toward the management of tooth staining. Laser-assisted bleaching is needed before adhesive restorations and has become common and advantageous as it accelerates bleaching action, reduces postoperative sensitivity, and promotes recrystallization of enamel. Aim: The study aimed to evaluate and compare the bond strength of diode (Biolace: EpicX) and neodymium-doped:yttrium aluminum garnet (Nd:YAG) (LightWalker, Fotona, Slovenia) assisted bleached (Pola Office, SDI) enamel with nanofilled composite (GC Solare Sculpt). Materials and Methods: The samples were divided into three groups (n = 11): Group A - Conventionally bleached enamel, Group B - Diode laser-assisted bleached enamel, Group C - Nd:YAG laser-assisted bleached enamel. After storing samples in Artificial Saliva for 2 weeks, bonding was performed, and nanofilled composite resin was applied through an incremental method. Samples were subjected to shear bond strength (SBS) analysis. Conclusion: The use of Nd:YAG laser on bleached enamel significantly increases the bond strength with nanofilled composite resin.

17.
Small ; : e2403130, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38751304

RESUMO

Polycrystalline yttrium aluminum garnet (YAG) ceramic doped with neodymium (Nd), referred to as Nd:YAG, is widely used in solid-state lasers. However, conventional powder metallurgy methods suffer from expenses, time consumption, and limitations in customizing structures. This study introduces a novel approach for creating Nd:YAG ceramics with 3D free-form structures from micron (∼70 µm) to centimeter scales. Firstly, sol-gel synthesis is employed to form photocurable colloidal solutions. Subsequently, by utilizing a home-built micro-continuous liquid interface printing process, precursors are printed into 3D poly(acrylic acid) hydrogels containing yttrium, aluminum, and neodymium hydroxides, with a resolution of 5.8 µm pixel-1 at a speed of 10 µm s-1. After the hydrogels undergo thermal dehydration, debinding, and sintering, polycrystalline Nd:YAG ceramics featuring distinguishable grains are successfully produced. By optimizing the concentrations of the sintering aids (tetraethyl orthosilicate) and neodymium trichloride (NdCl3), the resultant samples exhibit satisfactory photoluminescence, emitting light concentrated at 1064 nm when stimulated by a 532 nm laser. Additionally, Nd:YAG ceramics with various 3D geometries (e.g., cone, spiral, and angled pillar) are printed and characterized, which demonstrates the potential for applications, such as laser and amplifier fibers, couplers, and splitters in optical circuits, as well as gain metamaterials or metasurfaces.

18.
ChemSusChem ; : e202400286, 2024 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-38786929

RESUMO

Permanent magnets (PMs) containing rare earth elements (REEs) can generate energy in a sustainable manner. With an anticipated tenfold increase in REEs demand by 2050, one of the crucial strategies to meet the demand is developing of efficient recycling methods. NdFeB PMs are the most widely employed, however, the similar chemical properties of Nd (20-30 % wt.) and Dy (0-10 % wt.) make their recycling challenging, but possible using appropriate ligands. In this work, we investigated commercially available 8-hydroxyquinolines (HQs) as potential Fe/Nd/Dy complexing agents enabling metal separation by selective precipitation playing on specific structure/property (solubility) relationship. Specifically, test ethanolic solutions of nitrate salts, prepared to mimic the main components of a PM leachate, were treated with functionalized HQs. We demonstrated that Fe3+ can be separated as insoluble [Fe(QCl,I)3] from soluble [REE(QCl,I)4]- complexes (QCl,I -: 5-Cl-7-I-8-hydoxyquinolinate). Following that, QCl - (5-Cl-8-hydroxyquinolinate) formed insoluble [Nd3(QCl)9] and soluble (Bu4N)[Dy(QCl)4]. The process ultimately gave a solution phase containing Dy with only traces of Nd. In a preliminary attempt to assess the potentiality of a low environmental impact process, REEs were recovered as oxalates, while the ligands as well as Bu4N+ ions, were regenerated and internally reused, thus contributing to the sustainability of a possible metal recovery process.

19.
Ophthalmic Res ; 67(1): 292-300, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38718759

RESUMO

INTRODUCTION: Cataract extraction is the most frequently performed ophthalmological procedure worldwide. Posterior capsule opacification remains the most common consequence after cataract surgery and can lead to deterioration of the visual performance with cloudy, blurred vision and halo, glare effects. Neodymium-doped yttrium aluminum garnet (Nd:YAG) laser capsulotomy is the gold standard treatment and a very effective, safe and fast procedure in removing the cloudy posterior capsule. Damaging the intraocular lens (IOL) during the treatment may occur due to wrong focus of the laser beam. These YAG-pits may lead to a permanent impairment of the visual quality. METHODS: In an experimental study, we intentionally induced YAG pits in hydrophilic and hydrophobic acrylic IOLs using a photodisruption laser with 2.6 mJ. This experimental study established a novel 3D imaging method using correlative X-ray and scanning electron microscopy (SEM) to characterize these damages. By integrating the information obtained from both X-ray microscopy and SEM, a comprehensive picture of the materials structure and performance could be established. RESULTS: It could be revealed that although the exact same energies were used to all samples, the observed defects in the tested lenses showed severe differences in shape and depth. While YAG pits in hydrophilic samples range from 100 to 180 µm depth with a round shape tip, very sharp tipped defects up to 250 µm in depth were found in hydrophobic samples. In all samples, particles/fragments of the IOL material were found on the surface that were blasted out as a result of the laser shelling. CONCLUSION: Defects in hydrophilic and hydrophobic acrylic materials differ. Material particles can detach from the IOL and were found on the surface of the samples. The results of the laboratory study illustrate the importance of a precise and careful approach to Nd:YAG capsulotomy in order to avoid permanent damage to the IOL. The use of an appropriate contact glass and posterior offset setting to increase safety should be carried out routinely.


Assuntos
Lasers de Estado Sólido , Lentes Intraoculares , Lasers de Estado Sólido/uso terapêutico , Imageamento Tridimensional , Microscopia Eletrônica de Varredura/métodos , Humanos
20.
IUCrdata ; 9(Pt 3): x240175, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38586517

RESUMO

Neodymium(III) ortho-oxidotungstate(VI) was synthesized as a side-product in an unsuccessful synthesis attempt at fluoride derivatives of neodymium tungstate in fused silica ampoules, using neodymium(III) oxide, neodymium(III) fluoride and tungsten trioxide. Violet, platelet-shaped single crystals of the title compound emerged of the bulk, which crystallize in the defect scheelite type with a trigonal dodeca-hedral coordination of oxide anions around the Nd3+ cations and the hexa-valent tungsten cations situated in the centers of oxide tetra-hedra.

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