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This study investigated the impact of various Ge132 (Bis-carboxyethyl germanium sesquioxide) concentrations on frozen bovine semen. Ejaculates from three bulls were pooled and divided into six groups, each one with different Ge132 concentrations (0, 500, and 1000 µg/mL) and each group was incubated in different conditions (33°C for 30 min (D: D0, D500, and D1000), and the other was immediately cooled to 4°C (R: R0-control; R500 and R1000)). Thawed semen was evaluated for sperm characteristics by CASA and flow cytometer. Results showed better motility in the immediate cooling group without Ge132 compared with high Ge132 concentrations. Values for total motility dropped after 5 and 60 min in groups with high Ge132 levels and some control groups. Linearity increased with 1000 µg/mL Ge132, while straightness differed between moments in multiple groups. Membrane integrity was higher in a control group and certain Ge132 groups. Lower O2 - generation occurred without Ge132. After oxidative stress induction, lipid peroxidation intensity increased with arachidonic acid, but D1000 had lower peroxidation than R0. Overall, Ge132 appears to have provided protection against PLM when subjected to oxidative stress, since even at high concentrations it maintained sperm metabolism.

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Objective.In cities situated at high-altitude, the measured x-ray spectra are required to calculate the absorbed dose to water in radiobiology and medical dosimetry because of the air-density effect. This work aims to measure, in a high-altitude city, a set of x-ray spectra from an x-ray tube with tungsten anode generated at potentials of the M-series x-ray beams from NIST in the range of 20 and 150 kV as well as other beam qualities that have been characterized and used for dosimetry study in our group called W-series. To also measure some spectra of mammography interest in the energy range of 25 and 35 kV using additional filtration of rhodium (Rh), molybdenum (Mo) and silver (Ag).Approach.A tungsten anode x-ray tube with potential between 10 to and 160 kV was used. A high-purity germanium (HPGe) detector associated with a DSPEC Jr 2.0TMdigital signal processing module has been used for the spectra measurements. Prior the spectra measurements, the HPGe detector has been characterized and calibrated using several radioactive sources. Mainresults.The M80 spectrum was compared to a mathematically filtered beam from Physicalisch Technische Bundesanstalt corresponding to the same potential finding a difference of 0.7% in the average energy. So, the mathematically filtered beam from PTB matches very well our M80 beam. The beams M80, M100 and M120 were also compared with calculations for the corresponding kilovoltage from an executable that calculates x-ray spectra from tungsten anode x-ray tubes in the energy range between 40 to 300 kV called SpekCalc. The SpekCalc reproduces qualitatively the experimental spectra, but not quantitatively, mainly for M100 and M120 beams.Significance.These spectra can be used to simulate the patient dose as well as image quality using Monte Carlo (MC) codes or to evaluate the absorbed dose in dosimetry studies.

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In this work a plasmonic sensor with a D-Shaped microstructured optical fiber (MOF) is proposed to detect a wide range of analyte refractive index (RI ;na) by doping the pure silica (SiO2) core with distinct concentrations of Germanium Dioxide (GeO2), causing the presentation of high spectral sensitivity. In this case, the fiber is shaped by polishing a coating of SiO2, on the region that will be doped with GeO2, in the polished area, a thin gold (Au) layer, which constitutes the plasmonic material, is introduced, followed by the analyte, in a way which the gold layer is deposited between the SiO2. and the analyte. The numerical results obtained in the study shows that the sensor can determine efficiently a range of 0.13 refractive index units (RIU), with a limit operation where na varies from 1.32 to 1.45. Within this application, the sensor has reached an average wavelength sensitivity (WS) of up to 11,650.63 nm/RIU. With this level of sensitivity, the D-Shaped format and wide range of na detection, the proposed fiber has great potential for sensing applications in several areas.

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Here, we explore effects of metallophore-producing rhizobacteria on the plant availability of germanium (Ge) and rare earth elements (REEs). Five isolates of the four species Rhodococcus erythropolis, Arthrobacter oxydans, Kocuria rosea and Chryseobacterium koreense were characterized regarding their production of element-chelators using genome-mining, LC-MS/MS analysis and solid CAS-assay. Additionally, a soil elution experiment was conducted in order to identify isolates that increase solubility of Ge and REEs in soil solution. A. oxydans ATW2 and K. rosea ATW4 released desferrioxamine-, bacillibactin- and surfactin-like compounds that mobilized Ge and REEs as well as P, Fe, Si and Ca in soil. Subsequently, oat, rapeseed and reed canary grass were cultivated on soil and sand and treated with cells and iron depleted culture supernatants of A. oxydans ATW2 and K. rosea ATW4. Inoculation increased plant yield and shoot phosphorus (P), manganese (Mn), Ge and REE concentrations. However, effects of the inoculation varied substantially between the growth substrates and plant species. On sand, A. oxydans ATW2 increased accumulation of REEs in all plant species and root-shoot translocation in rapeseed, while K. rosea ATW4 enhanced REE accumulation in rapeseed only, without effects on other plant species. Sand-cultured oat plants showed increased Ge accumulation and root-shoot translocation in presence of A. oxydans ATW2 cells and K. rosea ATW4 supernatant; however, there was no effect on other plant species, irrespective the growth substrate used. In contrast, soil-cultured rapeseed showed enhanced REE accumulation in presence of cells of A. oxydans ATW2 while there were no effects on other plant species and Ge. The processes involved are not yet fully understood. Nevertheless, we demonstrated that chemical microbe-soil-plant relationships influence plant availability of nutrients together with Ge and REEs, which has major implications on our understanding of biogeochemical element cycling and development of sustainable bioremediation and biomining technologies.

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The interactions in model ionic YTX3···Z (Y = NC, F, Cl, Br; X = F, Cl, Br, Z = F-, Cl-, Br-, Li+) dyads containing the tetrel atoms, T = C, Si, Ge, were studied using ab initio computational methods, including an energy decomposition analysis, which found that the YTX3 molecules were stabilized by both anions (via tetrel bonding) and cations (via polarization). For the tetrel-bonded dyads, both the electrostatic and polarization forces make comparable contributions to the binding in the C-containing dyads, whereas, electrostatic forces are by far the largest contributor to the binding in the Si- and Ge-containing analogues. Model metastable Li+···NCTCl3···F- (T = C, Si, Ge) triads were found to be lower in energy than the combined energy of the Li+ + NCTCl3 + F- fragments. The pair energies and cooperative energies for these highly polar triads were also computed and discussed.

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A microwave-induced plasma optical emission spectrometer with N2-based plasma was combined with a multimode sample introduction system (MSIS) for hydride generation (HG) and multielemental determination of As, Bi, Ge, Sb, and Sn in samples of forage, bovine liver, powdered milk, agricultural gypsum, rice, and mineral fertilizer, using a single condition of prereduction and reduction. The accuracy of the developed analytical method was evaluated using certified reference materials of water and mineral fertilizer, and recoveries ranged from 95 to 106%. Addition and recovery experiments were carried out, and the recoveries varied from 85 to 117% for all samples evaluated. The limits of detection for As, Bi, Ge, Sb, and Sn were 0.46, 0.09, 0.19, 0.46, and 5.2 µg/L, respectively, for liquid samples, and 0.18, 0.04, 0.08, 0.19, and 2.1 mg/kg, respectively, for solid samples. The method proposed offers a simple, fast, multielemental, and robust alternative for successful determination of all five analytes in agricultural samples with low operational cost without compromising analytical performance.

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This study aimed at assessing the incorporation of radionuclides in animals in the proximity of the uranium mine in Caetité, Brazil. In 2014, samples of bovine and equine teeth and skull bones were collected and their contents of natural and artificial isotopes were assessed using nuclear spectrometry techniques. Gamma ray emission from 226,228Ra and 40K isotopes was determined using high-purity germanium (HPGe) spectrometry, 90Sr radioactivity was measured with liquid scintillation, and 234,238U, 232,230,228Th, 210Po and 239+240Pu radioactivity was assessed with alpha-spectrometry. Prior to the measurements, sample dissolutions and isotope separations were performed. Our results indicate a high 228Th isotope content in the skull bones and the teeth of animals, up to 179 Bq per kg of ash. The 226Ra and 228Ra concentrations were slightly lower. Activity concentrations of other isotopes were significantly lower or below the detection limit. We could not identify sources of technologically enhanced levels of 228Ra in the area we investigated; therefore we suggest that their origin is natural.

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Germanium- and tellurium-based glasses have been largely studied due to their recognized potential for photonics. In this paper, we review our recent studies that include the investigation of the Stokes and anti-Stokes photoluminescence (PL) in different glass systems containing metallic and semiconductor nanoparticles (NPs). In the case of the samples with metallic NPs, the enhanced PL was attributed to the increased local field on the rare-earth ions located in the proximity of the NPs and/or the energy transfer from the metallic NPs to the rare-earth ions. For the glasses containing silicon NPs, the PL enhancement was mainly due to the energy transfer from the NPs to the Er(3+) ions. The nonlinear (NL) optical properties of PbO-GeO2 films containing gold NPs were also investigated. The experiments in the pico- and subpicosecond regimes revealed enhanced values of the NL refractive indices and large NL absorption coefficients in comparison with the films without gold NPs. The reported experiments demonstrate that germanate and tellurite glasses, having appropriate rare-earth ions doping and NPs concentration, are strong candidates for PL-based devices, all-optical switches, and optical limiting.

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The vibrational dispersion relations of porous germanium (pGe) and germanium nanowires (GeNWs) were calculated using the ab initio density functional perturbation theory with a generalized gradient approximation with norm-conserving pseudopotentials. Both pores and nanowires were modeled using the supercell technique. All of the surface dangling bonds were saturated with hydrogen atoms. To address the difference in the confinement between the pores and the nanowires, we calculated the vibrational density of states of the two materials. The results indicate that there is a slight shift in the highest optical mode of the Ge-Ge vibration interval in all of the nanostructures due to the phonon confinement effects. The GeNWs exhibit a reduced phonon confinement compared with the porous Ge due to the mixed Ge-dihydride vibrational modes around the maximum bulk Ge optical mode of approximately 300 cm⁻¹; however, the general effects of such confinements could still be noticed, such as the shift to lower frequencies of the highest optical mode belonging to the Ge vibrations.

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This paper describes the adsorption of sodium dodecyl sulfate (SDS) molecules in a low polar solvent on Ge substrate by using Fourier transform infrared-attenuated total reflection (FTIR-ATR) spectroscopy and atomic force microscopy (AFM). The maximum SDS amount adsorbed is (5.0 ± 0.3) × 10(14) molecules cm(-2) in CHCl(3), while with the use of CCl(4) as subphase the ability of SDS adsorbed is 48% lower. AFM images show that depositions are highly disordered over the interface, and it was possible to establish that the size of the SDS deposition is around 30-40 nm over the Ge surface. A complete description of the infrared spectroscopic bands for the head and tail groups in the SDS molecule is also provided.

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This work reports on the spectral dependence of both nonlinear refraction and absorption in lead-germanium oxide glasses (PbO-GeO2) containing silver nanoparticles. We have found that this material is suitable for all-optical switching at telecom wavelengths but at the visible range it behaves either as a saturable absorber or as an optical limiter.

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Esta investigación trata sobre la determinación de germanio en exudado de hojas de zábila, mediante la técnica ana lítica espectrometría de absorción atómica con atomización electrotérmica (ETAAS). El exudado de las hojas de zábila es el líquido amarillo y de sabor amargo que emana de las hojas de la planta cortadas en la base. Es también conocido como zumo o látex. Ha sido utilizado en el tratamiento de diversas afecciones tales como: tratamiento de heridas, infecciones bucales, irritaciones de la piel, otras. El germanio es un oligoelemento que ha sido utilizado como inmunoestimulante y en pacientes con neoplasia. La concentración del germanio presente en el exudado de Aloe vera (L.) Burm.f. fue de 7.42 ± 2.33 μg/g. La metodología empleada fue validada por estudio de recuperación, ubicándose en un valor promedio de 97.43 ± 2.22%. La desviación estándar relativa fue de 2.88%, lo que es un indicativo de la precisión. El método utilizado para la determinación del elemento en cuestión es exacto, preciso y libre de interferencias.

The objective of this work was to determine the concentration of germanium in Aloe vera (zábila) from leaves exudated, using the electrothermal atomic absorption spectrometry analytical technic (ETAAS). The exudated is a yellow and bitter liquid, used in wounds healing, skin irritations, mouth infections, etc. The germanium is a trace element used as immunestimulant in patients with tumour. A concentration of 7.42 ± 2.33 μg/g was found. The method for the determination of germanium was validated by recovery studies, a value of 97.43 ± 2.22% was obtained for germanium, and the relative standar deviation (RSD%) was 2.88%. The method was exact, precise and free from interferences.

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A microscopic theory of the Raman scattering based on the local bond-polarizability model is presented and applied to the analysis of phonon confinement in porous silicon and porous germanium, as well as nanowire structures. Within the linear response approximation, the Raman shift intensity is calculated by means of the displacement-displacement Green's function and the Born model, including central and non-central interatomic forces. For the porous case, the supercell method is used and ordered pores are produced by removing columns of Si or Ge atoms from their crystalline structures. This microscopic theory predicts a remarkable shift of the highest-frequency of first-order Raman peaks towards lower energies, in comparison with the crystalline case. This shift is discussed within the quantum confinement framework and quantitatively compared with the experimental results obtained from porous silicon samples, which were produced by anodizing p--type (001)-oriented crystalline Si wafers in a hydrofluoric acid bath.

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The lung counter facility of the Nuclear Regulatory Authority (ARN) is presented. A calibration was carried out using the Lawrence Livermore National Laboratory (LLNL) phantom. This phantom is provided with a pair of lungs and lymph nodes containing uranium homogeneously distributed and a set of four overlay plates covering a chest wall thickness (CWT) ranging from 1.638 to 3.871 cm. Individual organ calibration factors were acquired for 235U photopeaks energies and for each effective chest thickness. Using these factors, a collection of theoretical fitting curves were found. A counting efficiency formulae and a curve for simultaneously active lymph nodes and lung was obtained and checked through measures. Background measurements of the chamber with and without volunteer persons were performed in order to obtain the detection limits (DL) of the system. As this task involves the knowledge of the volunteers CWTs, these magnitudes were determined through formulae selected from the literature taking into account the detection system characteristics. The deviation in the CWT assigned to an individual, generated by applying different equations, produces variations up to 33% in the estimations of the incorporated activity and DL. An analysis of the changes in efficiencies as consequences of the detectors locations and CWT was also performed. This reveals that the DL of the camera (detectors, shield and blank phantom) is between 2.7 and 6.4 Bq of 235U, which implies 4.9 and 11.5 mg lung burden of natural uranium. An estimation of the minimum detectable intake performed with the DL considering blank persons shows that a system with the characteristics described is only adequate for non-routine individual monitoring.

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The geometry of iodotrimethylgermane has been determined by experimental and computational methods. Fourier transform infrared spectra have been recorded over a range of temperatures along with the Raman spectrum to obtain comprehensive vibrational data for the fundamental modes. The stretching, rocking, and deformation bands of the methyl groups have been resolved into their components with the aid of low-temperature infrared spectroscopy using Fourier self-deconvolution and curve-fitting methods. The optimized geometries and vibrational harmonic frequencies were calculated by density functional theory methods employing Pople-type basis sets, as well as those with descriptions for an effective core potential describing both germanium and iodine atoms. A scaled quantum mechanical analysis was carried out to yield the best set of harmonic force constants and obtain a transferable set of scale factors that can be applied to the (CH3)(3-)GeX (X = H, Cl, Br, I) series.

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El germanio y el silicio poseen una estructura electrónica externa idéntica, así como características geoquímicas similares. Debido a esto, la mayor cantidad de Ge presente en la corteza terrestre se encuentra disperso en distintos silicatos, en cantidades cercanas a las pocas partes por millón. Comúnmente se presenta como elemento traza, con una concentración promedio de 1ppm en rocas de la corteza terrestre. Sin embargo, las mayores acumulaciones de Ge se presentan asociadas a dos ambientes geológicos no silicatados: a) depósitos de sulfuros enclavados en rocas sedimentarias y b) carbones y materiales leñosos carbonizados. La relación Ge/Si en rocas, aguas y sedimentos es afectada por diversos procesos exógenos. Este último aspecto ha permitido utilizar el fraccionamiento de estos elementos para estudiar el balance de masa de los océanos y como indicador geoquímico de variación en los procesos de meteorización. Por otro lado, su inclusión preferencial sobre materiales carbonosos ha permitido proponerlo como indicador de procesos singenéticos y diagenéticos en carbones, así como una potencial fuente de este elemento en la naturaleza. En Venezuela se presentan algunos ambientes potenciales para la acumulación de Ge, particularmente aquellos asociados a las grandes cuencas carboníferas y a los depósitos de sulfuros masivos

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Two new germanates, Ge7O12(OH)4 (C4N3H13)(0.5)(H2O)5 (1) and Ge7O12(OH)4(H2O)6 (2) have been synthesized under hydrothermal conditions and characterized by IR spectroscopy, powder XRD, TG, and single-crystal X-ray diffraction. Compound 1 crystallizes in cubic space group P3m (No. 215) with a = b = c = 7.7119(5) A, v = 458.65(5) A(3), z = 1. Compound 2: cubic, P3m, a = b = c = 7.7653(17) A, v = 457.48(17) A(3), z = 1. Both germanates keep the same topological novel inorganic framework, which is assembled from Ge4(OH)4 cubane and chiral intertwined Ge-O double helices.

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The Monte Carlo method was used to calculate the efficiency, escape and Compton curves of a planar high-purity germanium detector (HPGe) in the 20-150 keV energy. These curves were used for the determination of photons spectra produced by an X-ray machine in order to allow a precise characterization of photon beams applied to medical diagnosis. The detector was modeled with the MCNP5 computer code and validated by comparison with experimental data. The air kerma calculated after the spectra stripping was compared with ionization chamber measurements.

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Single microcrystals of the new compound samarium dimanganese germanium oxide, SmMn2GeO7, were grown using the flux method in a double spherical mirror furnace (DSMF). The micrometric crystals were observed and chemically analysed with scanning electron microscopy (SEM) and X-ray energy dispersive spectroscopy (EDX). The structural characterization and chemical analysis of these crystals were also carried out using transmission electron microscopy (TEM) and high-resolution transmission electron microscopy (HRTEM), together with electron-energy-loss spectroscopy (EELS). We found that the new quaternary compound crystallizes in the orthorhombic system with the point group mmm (D2h), space group Immm (No. 71) and cell parameters a=8.30 (10), b=8.18 (10), c=8.22 (10) A and V=558.76 A3.

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The X-ray spectra applied in diagnostic radiology to the energy range between 50 and 125 kVp, were experimentally determined using a high-purity germanium detector, (HP)Ge, coupled to a multichannel analyser. A simple stripping procedure was implemented, according to that described by Seelentag and Panzer, to correct the pulse height distribution and then to determine the photon spectra. The measurements were performed for those conditions where the X-ray beam is transmitted through Pb filters 0.2-0.7 mm thick. It was necessary to estimate the effective dose in the same way that it is done for radiology diagnosis room shielding projects. The spectra were also determined to the X-ray qualities recommended by the IEC for primary diagnostic X-ray and for X-ray beams attenuated by aluminium filters 2.5-42.5 mm thick. The spectra obtained were compared with data derived from the literature presenting good agreement.

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