Search

Copyright of Pamukkale Medical Journal is the property of Pamukkale Journal of Medicine and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Triglycine sulfate (TGS) crystals are pyroelectric crystals that exhibit ferroelectricity in a room-temperature environment. They have application as infrared detector elements. In this study, it was found that irradiation with 40-GHz electromagnetic waves accelerates the growth of TGS crystals, with a growth rate about 2.2 times faster than that without irradiation. This leads to a reduction in process time and therefore crystals that will be used as elements in the production of detectors can be obtained more quickly. The TGS crystals were irradiated with a CO2 laser at a wavelength of 10.6 μm. The maximum voltage value obtained was about 0.24 V, the photosensitivity was 24.7 V/W, and the noise equivalent power (NEP) was 2.7 × 10−8 W/Hz½. In addition, it was confirmed that the sensitivity increased with decreasing area of the crystal. These results show that TGS crystals grown under electromagnetic irradiation can be used as infrared detector elements. [ABSTRACT FROM AUTHOR]

In this study, a detector is developed using deuterated L‐alanine doped triglycine sulfate (DLATGS) crystals capable of detecting circularly polarized light (CPL) and various polarization states. As a primary pyroelectric detection crystal, DLATGS has exhibited notable optical responses to both linearly and circularly polarized light during the tests, demonstrating a favorable polarization ratio of 3.86 and an anisotropic factor glph${g}_{lph}$ of 0.529. The research discovers the broad‐spectrum bulk photovoltaic (BPVE) characteristics in DLATGS, highlighting its potential for CPL detection. By integrating linear and circular bulk photovoltaic effect theories (LBPV and CBPV), the crystal's ability to differentiate between various polarization modes, including left‐/right‐handed polarized light, is confirmed. The BPVE and pyro‐phototronic coupling responses is characterized, laying a theoretical foundation for a rare pyroelectric effect‐based multifunctional polarization detector. The overall consistency of phenomena and theoretical framework bridges the gap between theoretical predictions and experimental validation. This work not only advances the understanding of DLATGS crystals but also sets the stage for further exploration into chiral materials and the development of TGS‐type crystals in future photoelectronic detectors. [ABSTRACT FROM AUTHOR]

Introduction: Iron deficiency is the most common cause of anemia in both sexes, although it is more common in women. Intravenous (IV) iron replacement is preferred in patients who cannot tolerate oral treatment or when iron stores need to be replenished rapidly. In this study, we wanted to share the ferric carboxymaltose (FCM) desensitization protocol that we self-created and successfully applied. Methods: This retrospective cross-sectional study included patients with a history of hypersensitivity reactions (HSRs) to IV or oral iron replacement and patients who were planned to receive IV iron replacement but were referred to the allergy clinic because of have risk factors (atopic diseases, history of HSR to other drugs, high serum tryptase levels, etc.) for HSRs. Before desensitization, some of the patients underwent skin tests (skin prick test and intradermal test) with FCM, and the results were recorded. Skin tests were not performed in patients with a history of drug use (antihistamine, systemic steroid, omalizumab, etc.) that affected the results of skin tests. All patients underwent a one-bag 8-step desensitization protocol with 500 mg FCM and were observed for 2 h after desensitization. Results: A total of 15 patients (14 females and 1 male) with a mean age of 41.13 ± 11.18 years were included in the study. When the patients were evaluated in terms of the risk of allergic reactions according to their clinical history, 8 patients had a history of anaphylaxis with iron preparations (FCM, n = 4; ferric hydroxide sucrose, n = 2; iron [II] glycine sulfate, n = 1; and iron [III] hydroxide polymaltose, n = 1), and 7 patients had a history of HSR other than anaphylaxis with iron preparations (urticaria, n = 6 [FCM, n = 2; iron (II) glycine sulfate, n = 2; and iron (III) hydroxide polymaltose, n = 2] and urticaria + angioedema [ferric hydroxide sucrose, n = 1]). Desensitization was successfully completed in all patients. No HSR was observed during or after the procedure in any of the patients. Conclusion: IV iron replacement is a very effective method, especially in cases where iron stores need to be replenished more rapidly. In patients with a history of iron HSR or at risk of developing HSR, replacement can be safely performed without an allergic reaction with successful desensitization protocols. [ABSTRACT FROM AUTHOR]

Simple Summary: The way poultry are fed affects the fatty acid profile of the meat. A sufficient supply of zinc (Zn) is crucial because this element is capable of modulating fatty acid metabolism and can affect the dietary quality of meat. Our study aimed to determine whether Zn glycine chelate used in the diets of Ross 308 broiler chickens can improve the dietary quality of meat due to a beneficial modification of the fatty acid profile. Using statistical methods, we confirmed the effect of the form (sulphate vs. glycine chelate) and/or quantity of Zn used (100% or 50% of the requirement) on the fatty acid profile and dietary quality of thigh meat. However, our results imply that it is sufficient to supply any form of Zn in the amount satisfying 50% of the chicken requirements for Zn to ensure satisfactory dietary quality of their meat. Studies concerning nutritional strategies for the modification of the dietary quality of meat by altering the fatty acid profile are significant to consumers, as such modification can produce good-quality meat for safe consumption without increasing the risk of diet-related civilisational diseases and can even contribute to reducing such a risk. The present study aimed to investigate the effect of mineral (sulphate) or organic (glycine chelate) forms of Zn used in quantities covering 100% or 50% of the Zn requirement on the fatty acid profile of the thigh muscles of Ross 308 broiler chickens. We also analysed the dietary value of this meat based on its fatty acid profile. The experimental factors did not influence the content of basic chemical components and the meat's pH. Although, in terms of statistics, the presented study supports the statement that the form (sulphate vs. glycine chelate) and/or amount of Zn used (100% or 50% of the requirement) affects the fatty acid profile and dietary value of thigh meat, the results imply that the requirement of Ross 308 broiler chickens for Zn was also covered in full when in it was used in amounts covering 50% of the requirement, irrespective of the form in which Zn was used. However, it cannot be explicitly confirmed that the form of Zn affects the analysed parameters of thigh meat. [ABSTRACT FROM AUTHOR]

In our studies, we combined two powdered materials, i.e., ferroelectric triglycine sulfate (TGS) and ferrimagnetic magnetite Fe3O4, to obtain a magnetoelectric composite. The ferroelectric (E) part, i.e., TGS, was a hybrid organic–inorganic crystal, which we obtained as a pure single crystal from an aqueous solution using a static water evaporation method. The magnetic (M) part of the composite was commercially available magnetite. The samples used for the dielectric and magnetoelectric measurements were cold-pressed and made in the form of a circular tablet. The measuring electrodes were made of silver-based conductive paste and were attached to the sample. We measured the temperature dependencies of selected electrical parameters (e.g., dielectric permittivity, electrical capacity, and loss angle tangent). We used the dynamic lock-in method to check whether magnetoelectric coupling existed between the E and M phases. In this paper, we present the dielectric properties of pure monocrystalline TGS as a reference sample and compare the results for TGS powder, TGS + carbon powder, and TGS + Fe3O4 powder. The magnetoelectric coupling presumably appeared for the composite TGS + 10 wt. % Fe3O4, as evidenced by the shift in the phase transition temperature in the TGS. Moreover, the theoretical interpretation of the effect is proposed. [ABSTRACT FROM AUTHOR]

The present work is a continuing study on anomalous properties of the ferroelectric nanocomposite from triglycine sulfate (TGS) and oxidized multiwalled carbon nanotubes (OMWCNT). In this study, the nature of frequency response in a region of 102–107 Hz at low temperatures (63–273 K) will be clarified by analyzing structural changes when reducing temperature. It was found that the interaction between TGS and OMWCNT inhibited the switching of SO4- groups, leading to a significant increase in relaxation time, activation energies and coercive fields. Consequently, the domain – wall freezing occurred at higher temperatures than those in pure TGS. [ABSTRACT FROM AUTHOR]

Objectives. Ferroelectric triglycine sulfate (TGS) belongs to a group of crystals whose properties are sensitive even to minor changes in growth conditions. The mechanism of spontaneous polarization in TGS is associated with the adjustment of protons which participate in the formation of hydrogen bonds. Therefore, the state of the parent solution plays an important role in the crystal formation. The study aims to investigate the structural features of TGS crystals grown using aqueous alcoholic solutions of technologically processed antibodies to interferon-gamma, in comparison with those of the crystals grown using the control solutions (technologically processed phosphate-buffered saline and intact aqueous alcoholic solution).Methods. X-ray diffraction assay and Raman spectroscopy.Results. The effect of solutions of the technologically processed antibodies to interferongamma added to a parent solution on the growth of TGS single crystals is established. This effect manifests in the changing in occupancy of the proton sublattice of the crystal grown from the parent solution containing technologically processed antibodies to interferon-gamma, as compared with the crystals grown from the control solutions. In the case of the crystal grown from the solution containing technologically processed antibodies to interferon-gamma, this change in the occupancy of the proton lattice is expressed in an increase in the length of N2–C3 bonds.Conclusions. Adding the technologically processed antibodies in the parent solution before the crystal growth can affect the structure of TGS crystals.

The Lucy Thermal Emission Spectrometer (L'TES) will provide remote measurements of the thermophysical properties of the Trojan asteroids studied by the Lucy mission. L'TES is build-to-print hardware copy of the OTES instrument flown on OSIRIS-REx. It is a Fourier Transform spectrometer covering the spectral range 5.71–100 μm (1750–100 cm−1) with spectral sampling intervals of 8.64, 17.3, and 34.6 cm−1 and a 7.3-mrad field of view. The L'TES telescope is a 15.2-cm diameter Cassegrain telescope that feeds a flat-plate Michelson moving mirror mounted on a linear voice-coil motor assembly to a single uncooled deuterated l-alanine doped triglycine sulfate (DLATGS) pyroelectric detector. A significant firmware change from OTES is the ability to acquire interferograms of different length and spectral resolution with acquisition times of 0.5, 1, and 2 seconds. A single ∼0.851 μm laser diode is used in a metrology interferometer to provide precise moving mirror control and IR sampling at 772 Hz. The beamsplitter is a 38-mm diameter, 1-mm thick chemical vapor deposited diamond with an antireflection microstructure to minimize surface reflection. An internal calibration cone blackbody target, together with observations of space, provides radiometric calibration. The radiometric precision in a single spectrum is ≤2.2 × 10−8 W cm−2 sr−1 /cm−1 between 300 and 1350 cm−1. The absolute temperature error is <2 K for scene temperatures >75 K. The overall L'TES envelope size is 37.6 × 29.0 × 30.4 cm, and the mass is 6.47 kg. The power consumption is 12.6 W average. L'TES was developed by Arizona State University with AZ Space Technologies developing the electronics. L'TES was integrated, tested, and radiometrically calibrated on the Arizona State University campus in Tempe, AZ. Initial data from space have verified the instrument's radiometric and spatial performance. [ABSTRACT FROM AUTHOR]

The adsorption of limonene enantiomers on chiral crystals of the ferroelectric triglycine sulfate was investigated. Homochiral crystals were synthesized under Viedma maturation conditions. Adsorption isotherms were obtained at temperatures below the Curie point (at 45°C), above the Curie point (100°C), and below the Curie point after heating at 100°C. Van Deemter curves for limonene enantiomers on the sample were constructed. Differences in equilibrium adsorption values were validated using the t-test. It was found that, below the Curie point, a difference in the adsorption isotherms of the limonenes is observed in the nonlinear adsorption isotherm region. At 100°C, no differences in the isotherms were observed. Furthermore, when the column temperature was reduced back to 45°C, no differences were observed either. It can be concluded that triglycine sulfate crystals do not possess chiral memory and that transition into the para-phase leads to irreversible loss of homochirality. [ABSTRACT FROM AUTHOR]

The dielectric hysteresis loops of a uniaxial triglycine sulfate (TGS) ferroelectric have been studied in a wide range of switching field frequencies. The experimental dependence of the coercive field on the switching frequency is compared with the Kolmogorov–Avrami domain switching model and the domain nucleation model. It is shown that both switching models agree reasonably well with the experiment and that the character of switched domain motion changes with a change in the switching field frequency. [ABSTRACT FROM AUTHOR]

The dielectric properties of ferroelectric composites and the specific features of the phase transitions occurring in them are discussed in comparison with the homogeneous ferroelectrics incorporated in the composites studied. The components incorporated into the dielectric matrix of ferroelectrics are considered to be triglycine sulfate, single crystals of potassium dihydrogen phosphate group, sodium nitrite, and perovskite-type materials. The factors changing the temperature range of polar phase existence in the ferroelectric composites under consideration are revealed and discussed. The results of the studies performed in this field are briefly reviewed. The work with the ferroelectric components incorporated into the aforementioned composites was performed in cooperation and under the guidance of L.A. Shuvalov. [ABSTRACT FROM AUTHOR]

The influence of a permanent magnetic field on macro- and nanoscopic properties of triglycine sulfate (TGS) crystals with impurity chromium (TGS-Cr) has been investigated. This work continues the previous studies of magnetically induced effects in ferroelectrics. A specific feature of TGS crystals is the presence of a nanoscale relief on a polar (010) cleavage; this nanorelief is a qualitative characteristic of the crystal defect structure. It is shown that the exposure of a crystal in a magnetic field of 2 T leads to a change in its dielectric properties, accompanied by a long-term transformation of the nanorelief. The results obtained are indicative of a magnetically induced change in the defect crystal structure. A qualitative difference is found between the magnetically induced effects in TGS-Cr crystals and undoped TGS crystals. The relationship between the magnetically induced effects and structural defects is discussed. [ABSTRACT FROM AUTHOR]

Copyright of China Surfactant Detergent & Cosmetics (2097-2806) is the property of China Surfactant Detergent & Cosmetics Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

A study on the effect of swift Heavy Ions Ti7+ @ (100 MeV) irradiated on TGS single crystal has been performed at various ion fluencies. UV–Vis-NIR absorption measurements suggest the tuning of energy gap upon irradiation and Eg values linearly decreased with respect to increase in ion fluences. From the Dielectric study, it has been identified that Curie temperature (Tc) of 〈011〉 TGS decreases to 322 K from 325 K upon irradiation, and peak boarding due to induced strain was also notified therein. Strikingly, upon irradiation the piezoelectric coefficient of the irradiated sample of 〈011〉 TGS got increased from 41 pC/N to a maximum of 52 pC/N for an ion fluencies of 1013 ions/cm2. The other significant results have been discussed in detail. [ABSTRACT FROM AUTHOR]

In this work, composite films of a copolymer of vinylidene fluoride with trifluoroethylene P(VDF-TrFE) comprising microcrystals of deuterated triglycine sulfate (DTGS) were produced. The pyroelectric properties of the composite samples were studied by the dynamic method. Pyroelectric measurements indicated an extreme dependence of the pyroelectric coefficient on the concentration of DTGS inclusions in the composite. Piezoelectric modules were macroscopically measured in static mode. The measured piezoelectric moduli d31 and d33 show ambiguous dependences on the volume fraction of DTGS inclusions. [ABSTRACT FROM AUTHOR]

The paper presents the results of the analysis of experimental dielectric hysteresis loops and field dependens of polarization switching of initial and annealed crystals of triglycine sulfate, doped copper (the concentration range (4,2–8,7) 10-3 wt.%). It has been experimentally established that their dielectric hysteresis loops do not have distortions. It has been found that the relative and effective permittivities and switchable polarization increase with increasing impurity concentration in crystals of TGS:Cu2+. The field dependences of the effective permittivity have extrema: before annealing the samples, the maxima of the εeff(E) curves correspond to a field value of about (20-40)∙103 V∙m-1, and for annealed samples these fields have a value of ~(15-30)∙103V∙m–1. Annealing of the samples increases the mobility of domain walls, which promotes the transformation of lenticular nuclei of domains into lamellae.

To fill the gap of earlier works for the nanocomposite based on a ferroelectric of triglycine sulfate (TGS) and a dielectric inclusion of cellulose nanoparticles (CNP), the present study provides experimental results for investigating anomalous switching properties via analyzing the features of dielectric (P-E) hysteresis loops. Different dielectric content of CNP (5, 15, 30, 50, 70 wt.%) was chosen. The P-E loops were measured at temperatures placed at the same distances from the phase transition point for all compositions. Besides, the influence of humidity (RH = 30, 60, 80, 100 %) was also investigated. It was clarified that the increase in cellulose content and relative humidity caused the increase in coercive field, accompanying the transformation of hysteresis loops from saturated into unsaturated ones. The nature of these anomalies was proposed to be associated with the role of hydrogen bonds in the composite.

Ferroelectric domain walls, across which there is a divergence in polarization, usually have enhanced electrical conductivity relative to bulk. However, in lead germanate, head-to-head and tail-to-tail walls are electrically insulating. Recent studies have shown that this is because, when oppositely oriented domains meet, polar divergence is obviated by a combination of domain bifurcation and suspected local dipolar rotation. To explore the uniqueness, or otherwise, of this microstructure, we have used tomographic piezoresponse force microscopy to map three-dimensional domain morphologies in another uniaxial ferroelectric system: triglycine sulfate. This mapping reveals an abundance of domain wall saddle points, which are characteristic of interlocking bifurcated domains. Conducting atomic force microscopy, performed close to the saddle points, showed no evidence for highly localized conducting domain wall sections, across which a divergence in polarization might be implied; this supports the notion that localized dipolar rotation occurs to minimize any potential polar discontinuity. Overall, our study, therefore, confirms that mutual domain bifurcation and suspected local dipolar rotation are not unique to lead germanate and instead may be widely present in other uniaxial ferroelectrics. [ABSTRACT FROM AUTHOR]

A polymorph of glycyl-L-alanine HI.H2O is synthesized from chiral cyclo-glycyl-L-alanine dipeptide. The dipeptide is known to show molecular flexibility in different environments, which leads to polymorphism. The crystal structure of the glycyl-L-alanine HI.H2O polymorph is determined at room temperature and indicates that the space group is polar (P21), with two molecules per unit cell and unit cell parameters a = 7.747 Å, b = 6.435 Å, c = 10.941 Å, α = 90°, β = 107.53(3)°, γ = 90° and V = 520.1(7) Å3. Crystallization in the polar point group 2, with one polar axis parallel to the b axis, allows pyroelectricity and optical second harmonic generation. Thermal melting of the glycyl-L-alanine HI.H2O polymorph starts at 533 K, close to the melting temperature reported for cyclo-glycyl-L-alanine (531 K) and 32 K lower than that reported for linear glycyl-L-alanine dipeptide (563 K), suggesting that although the dipeptide, when crystallized in the polymorphic form, is not anymore in its cyclic form, it keeps a memory of its initial closed chain and therefore shows a thermal memory effect. Here, we report a pyroelectric coefficient as high as 45 µC/m2K occurring at 345 K, one order of magnitude smaller than that of semi-organic ferroelectric triglycine sulphate (TGS) crystal. Moreover, the glycyl-L-alanine HI.H2O polymorph displays a nonlinear optical effective coefficient of 0.14 pm/V, around 14 times smaller than the value from a phase-matched inorganic barium borate (BBO) single crystal. The new polymorph displays an effective piezoelectric coefficient equal to d e f f = 280   p C N − 1 , when embedded into electrospun polymer fibers, indicating its suitability as an active system for energy harvesting. [ABSTRACT FROM AUTHOR]

The synthesis and growth of bulk size Glycine Zinc Sulphate Pentahydrate (GZS) single crystals are carried out by adopting the slow evaporation solution technique (SEST). Single crystal X-ray diffraction (XRD) study was carried out to confirm the structural parameters of the grown crystal. The structure belongs to the triclinic system with centrosymmetric space group of P 1 ¯ . The presence of point defects and grain boundaries was investigated by high-resolution X-ray diffraction analysis. FT-IR spectrum of GZS was analyzed and major functional groups were identified. Computational analysis was performed on the molecule by Gaussian 09W software using B3LYP/6-311G (d, p) and 6-311G + + (d, p) as the basis set and various theoretical parameters were determined. Optical transmittance was examined by UV–Visible spectroscopy and it was shown that the crystal is highly transparent with a UV–Vis cut-off of 230 nm. The optical band gap was evaluated as 5.12 eV. The photoluminescence (PL) showed that major emission occurs at 400 nm, and the average lifetime was evaluated using time-resolved photoluminescence (TRPL). Z-scan measurement was carried out to study the third-order nonlinear behaviour of the grown sample by Ti- sapphire laser. [ABSTRACT FROM AUTHOR]

Single crystals of pure triglycine sulfate (TGS) and yttrium‐acetate (0.5 mol%)‐doped triglycine sulfate (YTGS) crystals are synthesized and the crystals are grown from aqueous solution by slow evaporation solution growth method. The grown crystals are subjected to single crystal and powder X‐ray diffraction studies to identify the morphology and structure. Both the grown crystals are packed in a monoclinic crystal system and the lattice parameters of YTGS crystal are a = 9.138 Å, b = 12.72 Å, and c = 5.728 Å, whereas the doped TGS are, a = 9.134 Å, b = 12.61 Å, and c = 5.723 Å. The lattice parameters are slightly distorted due to the incorporation of yttrium ion into the lattice sites of the TGS crystal. The thermal stability of the grown crystals is investigated by differential thermal analysis (DTA) and thermogravimetric studies. DTA curve shows a lower decomposition temperature for YTGS crystal than for pure TGS crystal. The functional groups of the grown crystals are identified by Fourier transform infrared spectral studies. The surface morphology of the crystals is examined by scanning electron microscopy. Dielectric studies are carried out to identify the phase transition temperature and to find the dielectric constant of the YTGS crystals. [ABSTRACT FROM AUTHOR]

Peptides have essential structural and catalytic functions in living organisms. The formation of peptides requires the overcoming of thermodynamic and kinetic barriers. In recent years, various formation scenarios that may have occurred during the origin of life have been investigated, including iron(III)‐catalyzed condensations. However, iron(III)‐catalysts require elevated temperatures and the catalytic activity in peptide bond forming reactions is often low. It is likely that in an anoxic environment such as that of the early Earth, reduced iron compounds were abundant, both on the Earth's surface itself and as a major component of iron meteorites. In this work, we show that reduced iron activated by acetic acid mediates efficiently peptide formation. We recently demonstrated that, compared to water, liquid sulfur dioxide (SO2) is a superior reaction medium for peptide formations. We thus investigated both and observed up to four amino acid/peptide coupling steps in each solvent. Reaction with diglycine (G2) formed 2.0 % triglycine (G3) and 7.6 % tetraglycine (G4) in 21 d. Addition of G3 and dialanine (A2) yielded 8.7 % G4. Therefore, this is an efficient and plausible route for the formation of the first peptides as simple catalysts for further transformations in such environments. [ABSTRACT FROM AUTHOR]

The temperature behavior of the hysteresis loops and switching current parameters measured in the increasing field have been studied in single crystals of deuterated triglycine sulfate. We have revealed the hysteresis loops doubling leading to appearance of additional maxima at the field/time dependence of the switching current during cooling from 59.3 to 51.4°С. This effect was attributed to the bias fields arising as a result of bulk screening of depolarization field. Different current maxima corresponded to the switching in the areas with different values of bias field. [ABSTRACT FROM AUTHOR]

A combination of high‐resolution X‐ray diffraction and X‐ray diffraction topography was used for analysis and visualization of elastic strain in ferroelectric triglycine sulfate (TGS) single crystals under uniaxial compression. Diffraction peaks and topographs were obtained for both the 400 and 060 reflections of TGS in transmission geometry under gradually increased compression stress up to 3.5 MPa applied along the [100] and [010] crystallographic directions. All the diffraction data from the sample were obtained from the whole crystal volume with wide beam illumination. Analysis of diffraction patterns revealed a nonlinear increase in integral intensity versus stress and a linear increase in peak broadening versus stress for all compression measurement combinations. The topographs confirmed that the formation of uniform and non‐uniform strain fields depended on the direction of crystal compression and its relationship with integral intensity. A twinning process was found for the in‐plane reflection along the [100] direction. All the effects induced by compression were reversible after decompression of the sample. According to the results, a significant anisotropy of deformation processes depending on the crystallographic direction was observed, which can be explained by the proposed deformation mechanism with superposition of compression stress, the piezoelectric effect and ferroelectric domain evolution. [ABSTRACT FROM AUTHOR]

For the first time, the influence of fatigue and aging effects on phase transition and ferroelectric switching is studied for the composite based on ferroelectric polycrystals of triglycine sulfate and nanocellulose with different concentrations. The fatigue in samples was created by the exposure to a sinusoidal electric field, while the aging was investigated for samples after 240 h under dry conditions without the pre-exposure. It was figured out that the exposure led to the increase in phase transition temperature and the inhibition of polarization switching. On the contrary, the aging resulted in improving polarization switching and reducing the phase transition temperature. [ABSTRACT FROM AUTHOR]

To fill a gap of previous studies, the present work considers possible effects near electrodes for nanocomposites based on classical ferroelectrics (triglycine sulfate and potassium dihydrogen phosphate) filled with pristine and oxidized multiwalled carbon nanotubes by analyzing the spectra of electric impedance at low frequencies (10−3–106 Hz). FTIR technique was utilized to explore composite structures. The results indicated that using the oxidized carbon nanotubes helped to partially suppress the near-electrode effects due to the poor electrical conductivity of OH groups appeared after oxidization. Besides, the frequency region in which the effects existed was expanded with increasing the filler content. [ABSTRACT FROM AUTHOR]

The dynamics of the phase transition (PT) in triglycine sulfate crystals, either nominally pure or doped in different ways (upon homogeneous and profiled impurity introduction into the crystal) with chrome impurity (Сr3+), has been studied by analyzing the dielectric spectra measured in the ranges of frequencies 1–107 Hz and temperatures 23–60°C upon heating and cooling. It is shown that the introduction of impurity shifts the PT temperature range both upon heating and cooling. The PT temperature dynamics is found to depend both on the presence of impurity and on the way of its introduction into the crystal. The dependence of the width of the PT temperature range on the frequency at which the dielectric spectra were measured was shown to increase directly proportion to frequency. [ABSTRACT FROM AUTHOR]

In this work, we introduce lead-free organic ferroelectric perovskite N-methyl-N′-diazabicyclo[2.2.2]octonium)–ammonium triiodide (MDABCO-NH4I3) nanocrystals embedded in three different polymer fibers fabricated by the electrospinning technique, as mechanical energy harvesters. Molecular ferroelectrics offer the advantage of structural diversity and tunability, easy fabrication, and mechanical flexibility. Organic–inorganic hybrid materials are new low-symmetry emerging materials that may be used as energy harvesters because of their piezoelectric or ferroelectric properties. Among these, ferroelectric metal-free perovskites are a class of recently discovered multifunctional materials. The doped nanofibers, which are very flexible and have a high Young modulus, behave as active piezoelectric energy harvesting sources that produce a piezoelectric voltage coefficient up to geff = 3.6 VmN−1 and show a blue intense luminescence band at 325 nm. In this work, the pyroelectric coefficient is reported for the MDABCO-NH4I3 perovskite inserted in electrospun fibers. At the ferroelectric–paraelectric phase transition, the embedded nanocrystals display a pyroelectric coefficient as high as 194 × 10−6 Cm−2k−1, within the same order of magnitude as that reported for the state-of-the-art bulk ferroelectric triglycine sulfate (TGS). The perovskite nanocrystals embedded into the polymer fibers remain stable in their piezoelectric output response, and no degradation is caused by oxidation, making the piezoelectric perovskite nanofibers suitable to be used as flexible energy harvesters. [ABSTRACT FROM AUTHOR]

As reported in the literature, the doping of L,α-alanine (LA) led to increasing the phase transition temperature in triglycine sulfate (TGS) – a bio-ferroelectric material that has been widely applied in industry. The nature of this anomaly is commonly investigated by considerably complicated theoretical and experimental techniques. Unlike previous studies, the present work proposes a simple physical method of analyzing frequency spectra for dielectric loss to clarify the relationship between the movement of phase transition positions and the shift of relaxation frequencies observed in the spectra. The experimental results obtained for LA-doped TGS samples synthesized at different LA contents (0, 5, 10, 20, and 30 wt.%) were used for the analysis. It was indicated that the increase in phase transition temperature was accompanied by the decrease in relaxation frequencies due to the enhanced viscosity created by strong hydrogen bonds formed between amino acids of alanine and TGS structure.

Precise single-crystal structure analyses of the title compound, bis(glycinium) sulfate–glycine (1/1), 2C2H6NO2+·SO42−·C2H5NO2 (or C6H17N3O10S), non-deuterated triglycine sulfate (HTGS) at 20 K and 298 K were undertaken using time-of-flight neutron diffraction data. At 20 K for the O—H...O hydrogen bond between the glycinium cation and the zwitterionic, unprotonated glycine molecule that is associated with the ferroelectric behaviour of HTGS, O—H = 1.070 (3), H...O = 1.408 (3) [δ = 0.338 (4)], O...O = 2.4777 (15) Å and O—H...O = 179.0 (4)°, which is in good agreement with previous studies. Two reasonable structures for the same three atoms were refined for the 298 K dataset. One is a single-minimum potential-energy model, with O—H = 1.090 (12), H...O = 1.361 (12) [δ = 0.271 (17)], O...O = 2.450 (7) Å and O—H...O = 179.2 (10)°, having the H atom with a large ellipticity along the bond path between the O atoms. The other is a double-minimum potential-energy model having two H atom sites with occupancies of 0.876 (8) and 0.124 (8): for the major occupancy component, O—H = 1.065 (12), H...O = 1.387 (12), O...O = 2.451 (7) Å and O—H...O = 178.2 (11)° and for the minor component, O—H = 1.06 (4), H...O = 1.41 (4), O...O = 2.451 (7) Å and O—H...O = 166 (2)°. These models did not show any significant differences in R factors. In addition, the unit-cell parameters and other structural parameters of HTGS did not show any major differences compared to those of partially deuterated TGS and fully deuterated TGS for both 20 K and 298 K.

The third order nonlinear optical properties i.e. nonlinear refraction (n 2), absorption coefficient (β) and third order susceptibility χ(3) of glycine zinc sulphate pentahydrate (GZS) semi-organic single crystal was investigated under the excitation of Q-switched Nd-YAG laser pulsed radiations (λ = 532 nm & 1064 nm) by familiar Z-scan method. The values of nonlinear refraction (n 2), at 532 nm were 1.19 × 10−5 (cm2/GW), 2.09 × 10−5 (cm2/GW), 2.27 × 10−5 (cm2/GW), 2.48 × 10−5 (cm2/GW), and 2.55 × 10−5 (cm2/GW) at incident optical beam intensities of 0.76 (GW/cm2), 1.13 (GW/cm2), 1.17 (GW/cm2), 1.63 (GW/cm2) and 1.88 (GW/cm2) respectively while that of values at 1064 nm were 4.31 × 10−5 (cm2/GW), 4.69 × 10−5 (cm2/GW), 5.41 × 10−5 (cm2/GW) and 6.39 × 10−5 (cm2/GW) at incident optical beam intensities of 1.20 (GW/cm2), 1.25 (GW/cm2), 1.32 (GW/cm2) and 1.38 (GW/cm2) respectively. The values of nonlinear absorption coefficient (β) at 532 nm were −1.45 (cm/GW), −0.79 (cm/GW), −0.5 (cm/GW), 0.12 (cm/GW) and 0.64 (cm/GW) at incident optical beam intensities of 0.76 (GW/cm2), 1.13 (GW/cm2), 1.17 (GW/cm2), 1.63 (GW/cm2) and 1.88 (GW/cm2) respectively while that of values at 1064 nm were 0.62 (cm/GW), 0.74 (cm/GW), 0.77 (cm/GW) and 0.81 (cm/GW) at incident optical beam intensities of 1.20 (GW/cm2), 1.25 (GW/cm2), 1.32 (GW/cm2) and 1.38 (GW/cm2) respectively. The values of third order susceptibilities χ(3) at 532 nm were 0.83 × 10−12 (esu), 1.32 × 10−12 (esu), 1.42 × 10−12 (esu), 1.55 × 10−12 (esu) and 1.56 × 10−12 (esu) at intensities of 0.76 (GW/cm2), 1.13 (GW/cm2), 1.17 (GW/cm2), 1.63 (GW/cm2) and 1.88 (GW/cm2) respectively while that of values at 1064 nm were 2.71 × 10−12 (esu), 2.96 × 10−12 (esu), 3.4 × 10−12 (esu) and 4.02 × 10−12 (esu) at incident optical beam intensities of 1.20 (GW/cm2), 1.25 (GW/cm2), 1.32 (GW/cm2) and 1.38 (GW/cm2) respectively. It was seen that the sample showing saturable absorber to reverse saturable absorber at 532 nm wavelength at incident optical beam peak intensity (I 0) of 1.53 GW/cm2. Thus the crystal could be a potential candidate of optical switching application. It was also seen that the material possess positive nonlinearity. It was also found that the values of nonlinear absorption coefficient (β) and nonlinear refraction (n 2) increase with increase of excitation intensity irrespective of excitation wavelengths. [ABSTRACT FROM AUTHOR]

The article presents the results of studies of thermally induced domain processes in chromium-containing crystals of triglycine sulfate (TGS). It is shown that a change in the temperature of TGS:Cr3+ crystals in the absence of external electric fields is accompanied by a rearrangement of the domain structure, that occurs most intensively in the region of the phase transition. A depolarizing field of ~1,4·10^5 V m-1, which is generated by a gradient change in the temperature of the sample, causes the process of switching its domain structure. In unannealed crystals at impurity concentrations exceeding 5·10^(-3) wt.%, switching processes are hindered, and the intensity of thermally induced domain processes is significantly lower than that for samples with a lower impurity content. The intensity of the switching processes of TGS:Cr3+ crystals is significantly influenced by the rate of their heating. The dependences of the integral number of polarization-reversal jumps on the heating rate of the samples N=f(V) are extreme. The extrema of the N=f(V) curves lie in the rate intervals (0,2-0,8) K·sec^(-1). The domain structure of TGS:Cr3+ crystals consists of a matrix of the main domain, lenticular and lamellar domains. Evolution of the domain structure is observed under the influence of an electron beam, accompanied by the growth of domains, their coalescence, and sample switching. High-temperature annealing of crystals leads to their polydomenization.

Triglycine sulphate (TGS) and 1 and 2 mol% of magnesium chloride-doped TGS single crystals have been grown by using the slow evaporation solution method at room temperature. Pure and magnesium chloride-doped triglycine sulphate single crystals in a dimension of 12 × 12 × 5 cm3 have been grown at room temperature. The grown samples have been investigated by various characterization techniques such as single crystal X-ray diffraction, UV-VIS/NIR spectroscopy, dielectric studies, and energy dispersive X-ray analysis (EDAX). The single crystal X-ray diffraction studies revealed that both 1 and 2 mol% of MgCl2-doped TGS single crystals have been crystallized in monoclinic crystal structure with space group P21/m. The UV-VI/NIR spectra analysis confirmed that both pure and 1 and 2 mol% of MgCl2-doped TGS single crystals have wide optical transparency in the wavelength range of 236–1100 nm. The bandgap energy of both samples has been found to be 5.25 eV. The dielectric properties of the grown samples were recorded by measuring the dielectric constant as a function of temperature from 45 to 55°C with various frequencies (100 Hz – 1 MHz). The dielectric studies revealed that the dielectric constants of 1 and 2 mol% of MgCl2-doped TGS single crystals were increased with decreasing frequency and that the transition temperature was found to be 51°C. The EDAX spectrum confirmed the incorporation of MgCl2 into TGS single crystals. [ABSTRACT FROM AUTHOR]

Metabolomic analyses in alkaptonuria (AKU) have recently revealed alternative pathways in phenylalanine-tyrosine (phe-tyr) metabolism from biotransformation of homogentisic acid (HGA), the active molecule in this disease. The aim of this research was to study the phe-tyr metabolic pathway and whether the metabolites upstream of HGA, increased in nitisinone-treated patients, also undergo phase 1 and 2 biotransformation reactions. Metabolomic analyses were performed on serum and urine from patients partaking in the SONIA 2 phase 3 international randomised-controlled trial of nitisinone in AKU (EudraCT no. 2013-001633-41). Serum and urine samples were taken from the same patients at baseline (pre-nitisinone) then at 24 and 48 months on nitisinone treatment (patients N = 47 serum; 53 urine) or no treatment (patients N = 45 serum; 50 urine). Targeted feature extraction was performed to specifically mine data for the entire complement of theoretically predicted phase 1 and 2 biotransformation products derived from phenylalanine, tyrosine, 4-hydroxyphenylpyruvic acid and 4-hydroxyphenyllactic acid, in addition to phenylalanine-derived metabolites with known increases in phenylketonuria. In total, we observed 13 phase 1 and 2 biotransformation products from phenylalanine through to HGA. Each of these products were observed in urine and two were detected in serum. The derivatives of the metabolites upstream of HGA were markedly increased in urine of nitisinone-treated patients (fold change 1.2–16.2) and increases in 12 of these compounds were directly proportional to the degree of nitisinone-induced hypertyrosinaemia (correlation coefficient with serum tyrosine = 0.2–0.7). Increases in the urinary phenylalanine metabolites were also observed across consecutive visits in the treated group. Nitisinone treatment results in marked increases in a wider network of phe-tyr metabolites than shown before. This network comprises alternative biotransformation products from the major metabolites of this pathway, produced by reactions including hydration (phase 1) and bioconjugation (phase 2) of acetyl, methyl, acetylcysteine, glucuronide, glycine and sulfate groups. We propose that these alternative routes of phe-tyr metabolism, predominantly in urine, minimise tyrosinaemia as well as phenylalanaemia. [ABSTRACT FROM AUTHOR]

Copyright of Archives of Clinical & Experimental Medicine is the property of Archives of Clinical & Experimental Medicine and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Professor Boris Anatol'evich Strukov, a renowned scientist in the field of ferroelectrics, passed away at the age of 88 in Munich, Germany. He had a distinguished career at Moscow State University, where he made significant contributions to the study of phase transitions in ferroelectric crystals. Professor Strukov was known for his meticulous approach to experimental research and his dedication to understanding the underlying theories. His work challenged existing theories and provided valuable insights into the behavior of ferroelectric materials. He also co-authored a popular textbook on ferroelectricity and continued to engage in conceptual discussions even after retiring from teaching. Professor Strukov's legacy includes his numerous publications and his passion for scientific curiosity. [Extracted from the article]

A technique for studying the local elastic properties of inhomogeneous ferroelectrics has been proposed by the example of growth striations in triglycine sulfate crystals, layer-by-layer doped with chromium and L-α-alanine impurities. The data on the width and impurity compositions of stripes were obtained by X-ray fluorescence analysis and X-ray topography. The positions of the boundaries of the stripes emerging at the surface and the domain structure morphology were determined by the methods of correlation electrical atomic-force microscopy. The force curves were measured and Young's moduli were calculated for impurity-free and doped crystal stripes using contact atomic-force spectroscopy. The introduction of impurity decreases Young's modulus: the difference was found to be 20–25 and 12–14% for chromium and L-α-alanine, respectively. [ABSTRACT FROM AUTHOR]

A detailed description of a flexible and portable atomic layer deposition (ALD) system is presented for conducting in situ Fourier transform infrared (FTIR) absorption spectroscopy studies during the evolution and growth of ALD films. The system is directly integrated with a commercial FTIR spectrometer (Bruker Vertex 80V) to avoid the necessity of an external optical path to the instrument, thereby mitigating complexity and optical losses. In this work, we use potassium bromide (KBr) with a 5 nm layer of sputtered Si as a substrate due to higher infrared transmittance when compared to a single-side polished Si wafer. The FTIR absorption study is conducted at normal incidence in transmission mode using a deuterated L-alanine doped triglycine sulfate (DTGS) detector owing to its potential applicability for reliable measurements at wavenumbers below ∼700 cm−1. We demonstrate this by measuring ex situ the transverse optical phonon of bulk Al2O3 centered at 680 cm−1. The integrity and functionality of the system to track the nucleation stage are validated by conducting in situ FTIR absorption measurements of Al2O3 using tri-methyl aluminum (TMA) and H2O. The measured IR absorption spectra for the Al2O3 growth after each cycle of TMA and H2O show the formation and removal of CH3 (2800–3000 cm−1) groups on the substrate surface and CH4 (3016 and 1306 cm−1) molecules in the reactor, thus confirming the successful tracking of ligand exchange. Thus, this instrument, together with the choice of KBr as substrate, can enable straightforward ALD nucleation studies using a DTGS detector having sufficient signal without additional optical setup and modifications to off-the-shelf FTIR systems that allow low wavenumber experiments. [ABSTRACT FROM AUTHOR]

The combination of chirality and magnetism has steadily grown over the last decennia into an area of intense research. Magnetochiral anisotropy, chirality-induced spin-selectivity and helimagnetism are the most prominent phenomena resulting from this combination, touching different systems like topological (semi-)metals and insulators, quantum magnets, type II multiferroics and enantio-selective synthesis. As an extension to this area, we argue, based on symmetry arguments, that magnetochiral anisotropy will manifest itself in the displacement current in chiral dielectrics in a magnetic field. We confirm this conjecture by the experimental observation of very strong dielectric magnetochiral anisotropy near the ferroelectric phase transitions of triglycine sulfate and Rochelle salt, two of the oldest and most investigated chiral ferroelectrics. This effect opens a new playground in the study and characterisation of all chiral dielectrics. With our discovery, magnetochiral anisotropy now covers the (di)electrical properties of all condensed matter, from insulators to superconductors. The interplay between chirality and magnetism has been attracting much. Here, the authors show that the movement of bound charges in a chiral dielectric depends on the relative orientation between this movement and an external magnetic field. [ABSTRACT FROM AUTHOR]

[Display omitted] • Single crystals of glycine cobalt sulphate pentahydrate are effectively grown by slow evaporation solution technique at room temperature. • The Hirshfeld surface analysis of GCS reveals a complex landscape of intermolecular interactions within the crystal, with a predominant presence of O···H interactions. • The value of nonlinear optical parameter, the NLA coefficient was found to be 5.93 × 10−10 cm/W. This article encapsulates about synthesis and growth aspects of glycine cobalt sulfate pentahydrate (GCS) single crystal. It was grown using slow evaporation solution technique (SEST) at ambient conditions. The structural details were scrutinized from single crystal X-ray diffraction. FTIR analysis was carried out to confirm the presence of functional groups. The evaluation of intermolecular interactions was done through Hirshfeld surface analysis. Among the computational details, HOMO-LUMO studies were used to explain the electronic properties of the grown molecule. To understand the areas that are chemically active, the molecular electrostatic potential (MEP) was developed. The Mulliken atomic charge was done to know the distribution of charges within atoms. Optical quality of titled crystal was analysed through UV–visible spectroscopy. The investigation of third order nonlinear property was done using Z-scan technique with a femtosecond Ti:sapphire laser and estimation of nonlinear absorption coefficient was done. [ABSTRACT FROM AUTHOR]

Triglycine sulfate (TGS) single crystals doped with croconic acid (CA) were grown by evaporation from aqueous solutions. X-ray diffraction analysis shows a slight reduction in unit cell volume in TGS:CA compared to pure TGS crystals. The polarized Raman and near-infrared absorption spectra show that the positions of most lines resulting from inter- and intramolecular vibrations are in good agreement with those in spectra of undoped TGS crystals. The inclusion of CA in TGS is confirmed by the presence of bands characteristic of CA in the infrared-Fourier transform spectra. The ultraviolet-visible absorption spectra of TGS:CA are characterized by the presence of additional absorption bands (compared to the spectra of pure TGS) located in the transparent region of pure TGS. In the photon energy region 1.6–3.6 eV, a strong "green" luminescence band is present in TGS:CA upon excitation at λ = 325 nm. The position of the emission band depends on the wavelength of the exciting light. Doping of TGS with CA causes pinning of domain walls, which is accompanied by a decrease in amplitude and frequency dispersion of the dielectric anomaly at the phase transition, a decrease in the switchable polarization and an increase in the coercive field of hysteresis loops. [ABSTRACT FROM AUTHOR]

Dielectric properties of mixed composites based on TGS and nanocrystalline cellulose (1-x)TGS-xnCell composites with x = 0.2; 0.7, and 0.9 (x is the mass fraction of the cellulose) were studied within temperature range of 20 ÷ 120 °C. A smearing of the ferroelectric phase transition and an increase in its temperature in TGS crystallites included in the composite were found. An analysis of the experimental results for the 0.3TGS-0.7nCell composite showed that the diffuse ferroelectric phase transition ended abruptly in the vicinity of the temperature Tm ≈ 100 °C due to a structural rearrangement in TGS particles. [ABSTRACT FROM AUTHOR]

The dielectric and IR pyroelectric properties of a commercially available deuterated l-alanine-doped triglycine sulfate (DLATGS) material in wafer and microfilm form have been investigated experimentally. The DLATGS wafer exhibits a novel ferroelectric behavior at room temperature with a dielectric constant and loss tangent of 17 and 0.047 at 1 kHz, respectively. In contrast, The DLATGS microfilm shows an exceptional IR properties at frequency of 1 kHz in the room temperature. The results and analysis of DLATGS detector at 1 kHz using dielectric and IR pyroelectric test station show a specific detectivity (D*) between (2.61–3.44) × 108 (cm Hz1/2/W) with relatively low signal-to-noise ratio between (3.35–4.42) × 10–10 W/√Hz. The measured IR pyroelectric and dielectric results of DLATGS detector are greatly improved compared to standard values. The proposed results can be used in many applications, including, but not limited to: Fourier transform infrared, air quality monitoring, alcohol detection, anesthesiology testing, fire alarm systems, IR-flame detection, atmospheric temperature measurement, biomedical imaging, border patrol systems, earth resource detection, engine analysis, gas analyzers, human sensors, IR detection and spectrometers, and laser detection. [ABSTRACT FROM AUTHOR]

Formation and growth of isolated lenticular domains created by local switching using a biased tip of the scanning probe microscope in nominally pure triglycine sulfate single crystals have been studied experimentally. The obtained unusual change in the domain shape during growth has been considered in terms of a kinetic approach and attributed to simultaneous stochastic step generation for domain widening and deterministic nucleation (step generation at the domain vertices) for domain elongation. The main parameters of the domain wall motion have been extracted by fitting of the field dependence of the domain length and width. The obtained results provide a useful insight into the features of the domain structure kinetics in the uniaxial ferroelectrics and can be used for development of the domain engineering methods. [ABSTRACT FROM AUTHOR]

In the temperature range ΔT ≈ 321 K ÷ 322 K, the kinetics of the nonequilibrium domain structure of triglycine sulphate crystals, both pure and with specially introduced defects, has been studied by means of piezoresponse force microscopy technique. The temporal change in the domain structure as a set of regions with a scalar order parameter of P (r, t) = +1 and −1 for oppositely polarized domains was analysed by the behaviour of the space-time correlation function C(r,t) = ·Р(r,t)Р(0,t)Ò. At different distances from the Curie point Tc, the characteristic length Lc, as a scale measure of the average domain size, increases with time according to the power law Lc(t)~(t−t0)a. A decrease of the exponent a with distance from Tc can be a consequence of the transition of the domain structure of TGS crystals from a non-conservative state to a conservative one.

Polarization P(T) of triglycine sulfate (TGS) crystal shows distinct properties versus temperature, between 28 °C and the Curie point Tc. Carefully measured polarization versus temperature on several ranges is presented. The slopes on the curve P(T) on three temperature ranges between 28 ÷ 46 °C appear quite normal, while near the Curie point (47 °C ÷ Tc) behave abnormally, due to the domain walls. The relaxation time LOW, MIDDLE and HIGH appear very interesting. The MIDDLE relaxation time τM, between 40 ÷ 46 °C behave like the HIGH relaxation time τH between 47 and 48 °C and between −20 ÷ 10 °C (25 KBT) similar to LOW relaxation time τL (28KBT). The diagrams Cole-Cole of TGS are analyzed here for the first time. Roughly, several parameters change their slopes at 30, 42, and 47 °C. The values of ε′H and εʺH show about the same slope on the zones 42–47 °C and 30–42 °C. For the same zones, ε′L shows several increasing activation energies toward Curie point, except εʺL and RL whose activation energy decreases. Finally, we mention the opposite variation of the negative ordinate YCH, YCL of both arcs Cole-Cole and of the radius RH and RL. [ABSTRACT FROM AUTHOR]

Surface displacements of a few picometers, occurring after application of an electric potential to piezoelectric materials, can be detected and mapped with nanometer-scale lateral resolution by scanning probe methods, the most notable being piezoresponse force microscopy (PFM). Yet, absolute determination of such displacements, giving access for instance to materials' piezoelectric coefficients, are hindered by both mechanical and electrostatic side-effects, requiring complex experimental and/or post-processing procedures for carrying out reliable results. The employment of quartz tuning-fork force sensors in an intermittent contact mode PFM is able to provide measurements of electrically-induced surface displacements that are not influenced by electrostatic side-effects typical of more conventional cantilever-based PFM. The method is shown to yield piezoeffect mapping on standard ferroelectric test crystals (periodically-poled lithium niobate and triglycine sulfate), as well as on a ferroelectric polymer (PVDF), with no visible influence from the applied dc electric potential. [ABSTRACT FROM AUTHOR]

The Emirates Mars Mission Emirates Mars Infrared Spectrometer (EMIRS) will provide remote measurements of the martian surface and lower atmosphere in order to better characterize the geographic and diurnal variability of key constituents (water ice, water vapor, and dust) along with temperature profiles on sub-seasonal timescales. EMIRS is a FTIR spectrometer covering the range from 6.0-100+ μm (1666-100 cm−1) with a spectral sampling as high as 5 cm−1 and a 5.4-mrad IFOV and a 32.5×32.5 mrad FOV. The EMIRS optical path includes a flat 45° pointing mirror to enable one degree of freedom and has a +/- 60° clear aperture around the nadir position which is fed to a 17.78-cm diameter Cassegrain telescope. The collected light is then fed to a flat-plate based Michelson moving mirror mounted on a dual linear voice-coil motor assembly. An array of deuterated L-alanine doped triglycine sulfate (DLaTGS) pyroelectric detectors are used to sample the interferogram every 2 or 4 seconds (depending on the spectral sampling selected). A single 0.846 μm laser diode is used in a metrology interferometer to provide interferometer positional control, sampled at 40 kHz (controlled at 5 kHz) and infrared signal sampled at 625 Hz. The EMIRS beamsplitter is a 60-mm diameter, 1-mm thick 1-arcsecond wedged chemical vapor deposited diamond with an antireflection microstructure to minimize first surface reflection. EMIRS relies on an instrumented internal v-groove blackbody target for a full-aperture radiometric calibration. The radiometric precision of a single spectrum (in 5 cm−1 mode) is <3.0×10−8 W cm−2 sr−1/cm−1 between 300 and 1350 cm−1 over instrument operational temperatures (<∼0.5 K NE Δ T @ 250 K). The absolute integrated radiance error is < 2% for scene temperatures ranging from 200-340 K. The overall EMIRS envelope size is 52.9×37.5×34.6 cm and the mass is 14.72 kg including the interface adapter plate. The average operational power consumption is 22.2 W, and the standby power consumption is 18.6 W with a 5.7 W thermostatically limited, always-on operational heater. EMIRS was developed by Arizona State University and Northern Arizona University in collaboration with the Mohammed bin Rashid Space Centre with Arizona Space Technologies developing the electronics. EMIRS was integrated, tested and radiometrically calibrated at Arizona State University, Tempe, AZ. [ABSTRACT FROM AUTHOR]