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Salt solubility is generally determined under isotropic stress conditions. Yet, in the context of salt weathering of porous media, mechanical constraints on the in-pore growth of salt crystals are likely to be orientation-dependent, resulting in an anisotropic stress state on the crystal. In this paper, we determine by molecular simulation the solubility of NaCl in water when the crystal is subjected to anisotropic stress. Such anisotropy causes the chemical potential of the crystal to be orientation-dependent, and proper thermodynamic formulation requires describing the chemical potential as a tensor. The solute and crystal chemical potentials are computed from free energy calculations using Hamiltonian thermodynamic integration, and the usual condition of solubility is reformulated to account for the tensorial nature of the crystal chemical potential. We investigate in detail how the uniaxial compression of the crystal affects its solubility. The molecular simulation results led to revisiting the Correns law under anisotropic stress. Regarding the solute, the non-ideal behavior of the liquid phase is captured using Pitzer's ion interaction approach up to high concentrations of interest for in-pore crystallization and beyond the concentrations addressed in the existing literature. Regarding NaCl crystals, the validity of the generalized Gibbs–Duhem equation for a tensorial chemical potential is carefully verified, and it is found that crystallization progresses almost orthogonally to the crystal surface even under high shear stresses. Comparing uniaxial and isotropic compression highlights the major differences in solubility caused by stress anisotropy, and the revisited Correns law offers an appropriate framework to capture this phenomenon. [ABSTRACT FROM AUTHOR]

Evaporation-induced salt crystallization in complex porous structures is highly important for diverse scientific and industrial fields. Individual capillary tubes are elementary components used for investigating flow and transport in the interparticle interstices of porous media. In this study, the effects of the angularity and size of capillary tubes on water evaporation and salt crystallization were investigated through monitoring the receding meniscus, salt crystal morphology and growth process in capillary tubes with different cross sections. The Stefan diffusive and two-regional models were used to simulate evaporation from capillaries of different cross-sectional shapes in the absence and in the presence of salt, respectively. The evaporation process of deionized water in round tubes could be divided into two stages: the falling rate and the receding front stages. However, the evaporation process of deionized water for the square tubes, where a liquid film was formed, could be divided into three stages: a constant rate, receding front and falling rate stages. The salt evaporation rate was lower than that of deionized water owing to the lower water activity and obstruction from the salt crystals. The evaporation rate was proportional to the tube diameter for the round capillaries and inversely proportional to the inner side length of the square capillaries for both deionized water and the salt solution. Owing to the effect of thick liquid films on both the drying rate and ion transport, crystallization occurred in the bulk meniscus within a round tube, while crystallization preferentially occurred at the tube entrance for the square tubes. The agreement between the experimental observations and model simulations revealed that the two-region model was capable of describing the evaporation-induced salt crystallization in the square tubes. [ABSTRACT FROM AUTHOR]

In light of its complicated makeup and fluctuating states of ice and salt crystals, it is challenging to forecast the strength of sodium sulfate saline sand. To examine the strength and deformation properties of sodium sulfate saline sand with various salt levels, many indoor triaxial shear tests were conducted at −2°C, −5°C, −8°C, and 25°C. The strength of sodium sulfate saline sand was found to be affected by temperature and the salt content, and the probable corresponding processes were then demonstrated. The introduction of the linear comparison composite (LCC) approach and homogenization theory led to the development of an upscaling strength model for sodium sulfate sand. Each phase's mechanical characteristics and the interactions between different components were taken into consideration. The triaxial tests of both unfrozen and frozen saline sand served as a basis for the developed strength prediction model's validation. It is believed that the findings of this study would shed light on how saline sand gains its strength from macroscopic and mesoscopic viewpoints. [ABSTRACT FROM AUTHOR]

Three crystalline organic salts (melamine)2: (itaconic acid): 3H2O [(Hmem)22+·(itca2−)·(H2O)3, itca2− = itaconate] (1), (melamine)2:(2-bromo-but-2-enedioic acid):DMF:2H2O [(Hmem+)2·(bbda2−)·DMF·(H2O)2, bbda2− = 2-bromo-but-2-enedioate] (2) and (melamine):(α-ketoglutaric acid) [(Hmem+)·(Hketglua−), Hketglua− = hydrogen α-ketoglutarate] (3) were featured by X-ray diffraction analysis, IR, mp, and elemental analysis. Significant non-covalent interactions were calculated by means of the Hirshfeld surface analysis. All salts involve extensive N–H···OH-bonds as well as other non-covalent associations. The melamine polymers/dimers were set up at 1–2/3 by the pair of complmentary N–H···NH-bonds. The role of these non-covalent interactions in the crystal packing is ascertained. These weak interactions combined, all salts exhibited 3D framework motifs. The crystal structures of the salts from melamine, itaconic acid, 2-bromo-but-2-enedioic acid and α-ketoglutaric acid are predominantly stabilized by the classical hydrogen bonds as well as CH2···O, CH3···O, Br···Br, C···C, O···C, and π···π interactions. [ABSTRACT FROM AUTHOR]

A new type of material, organic salts in the crystal and crystalline powder state, with both excitation wavelength dependent (Ex‐De) fluorescence and Ex‐De phosphorescence under ambient conditions have been reported. The single component triphenylsulfonium chloride displays tunable fluorescent colors ranging from light purple to sky blue and tunable afterglow colors varying from green to yellowish green, to yellow (lifetimes: 57, 141, 66 ms, afterglow lasting for 2.1, 2.0, 2.3 s). The relationship between the structure and luminescence performance of 17 sulfonium salt derivatives confirms the pivotal roles of both the anions and the electronic and steric effect of substituent factors for luminescence. Single‐crystal analysis reveals that unique ionic bonding and intermolecular interaction can promote an ordered arrangement of organic salts in a crystal state, which then can facilitate molecular aggregation for phosphorescence generation. Theoretical calculations have also confirmed this viewpoint. More importantly, these sulfonium salt derivatives can be used for advanced multimodal anti‐counterfeiting and mitochondrial imaging, respectively. This study has not only expanded the scope of Ex‐De materials but also extended their applications. [ABSTRACT FROM AUTHOR]

Two-dimensional carbon nanosheets have garnered considerable interest as promising anode materials in energy storage devices due to their large specific surface area and excellent conductivity. The efficient synthesis of ultrathin nitrogen-doped carbon nanosheets is achieved with the aid of cysteine, employing a green ice/salt-assisted strategy. Ice influences the growth direction of salt crystals and determines the distribution of sodium lignosulfonate on the surfaces of both ice and salt crystals. The introduction of methionine incorporates heteroatoms, altering the electronic structure and chemical activity of the material, thereby effectively enhancing its lithium storage performance. The initial charge capacity of the optimized sample reached 766.4 mA h g−1 at a current density of 0.2 A g−1, maintaining a capacity of 571.1 mA h g−1 after 100 cycles. This study presents an innovative method for fabricating ultrathin carbon nanosheets using eco-friendly, cost-effective sodium lignosulfonate, showcasing a promising candidate for lithium-ion batteries and future energy storage technologies. [ABSTRACT FROM AUTHOR]

The performance and stability of perovskite solar cells rely crucially on the purity of their active perovskite phase. While the two‐step method has emerged as a well‐known technique for fabricating high‐performance cells, it suffers from significant PbI2 phase impurities at the buried layer due to inefficient diffusion of cationic molecules into the preprepared PbI2 layer. Herein, a simple yet highly effective method is presented to boost phase purity within the buried layer by introducing formamidinium iodide (FAI) seed molecules into the underlying PbI2 layer. X‐Ray diffraction analysis result reveals that this process significantly reduces the PbI2 phase and enhances the purity of the perovskite's phase. It is also observed that this technique can produce perovskite layer with a remarkably smooth surface structure and large interconnected crystal grains, forming a continuous layer. These characteristics are subjected to further enhancement when hexamethylenetetramine molecules are concurrently introduced with FAI into the PbI2 layer. Solar cells fabricated using this method, with an active area of 0.1 cm2, achieve a remarkable power conversion efficiency of up to 24.52% with Voc as high as 1.18 V, representing a substantial improvement over cells produced using the standard two‐step method, which attains only 22.18% efficiency. With its simple yet impactful approach, the present method should find widespread adoption in the production of high‐performance perovskite solar cells. [ABSTRACT FROM AUTHOR]

We demonstrate a machine learning-based approach which predicts the properties of crystal structures following relaxation based on the unrelaxed structure. Use of crystal graph singular values reduces the number of features required to describe a crystal by more than an order of magnitude compared to the full crystal graph representation. We construct machine learning models using the crystal graph singular value representations in order to predict the volume, enthalpy per atom, and metal versus semiconductor/insulator phase of DFT-relaxed organic salt crystals based on randomly generated unrelaxed crystal structures. Initial base models are trained to relate 89,949 randomly generated structures of salts formed by varying ratios of 1,3,5-triazine and HCl with the corresponding volumes, enthalpies per atom, and phase of the DFT-relaxed structures. We further demonstrate that the base model is able to be extended to related chemical systems (isomers, pyridine, thiophene and piperidine) with the inclusion of 2000 to 10,000 crystal structures from the additional system. After training a single model with a large number of data points, extension can be done at significantly lower cost. The constructed machine learning models can be used to rapidly screen large sets of randomly generated organic salt crystal structures and efficiently downselect the structures most likely to be experimentally realizable. The models can be used as a stand-alone crystal structure predictor, but may serve CSP efforts best as a filtering step in more sophisticated workflows. [ABSTRACT FROM AUTHOR]

Many studies have examined the morphological and micromorphological responses of different halophytes to determine their salt tolerance mechanisms. However, few studies have focused on the South African edible halophytes. This study examined the leaf micromorphology, elemental composition, and anatomical responses using scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDX) to examine salt tolerance levels in Trachyandra ciliata (L.F) Kunth. The treatments included varying sodium chloride (NaCl) concentrations: 50 mM, 100 mM, 150 mM and 200 mM, while control (0 mM) was watered with nutrient solution only. From the SEM micrographs, salt glands were observed protruding from the epidermis along the vascular system under low salinity and salt crystals appeared under higher concentrations, which makes this plant maintain cellular homeostasis under high salinity, and the plant can be classified as a recretohalophyte. Stomatal distribution, stomatal density and the number of open stomata decreased with increasing salinity. EDX revealed the presence of some important elements such as potassium, magnesium, phosphorus, calcium and more in the leaves. The results showed that increased salinity led to a decrease in the percentage composition of P, K and Ca2+, while Mg2+ was high under the control and low salinity (50 mM), decreased under 100 mM and increased again with increasing salinity. On the contrary, increasing salinity caused an increase in Na+ and Cl- in a stable manner. These findings reveal that T.ciliata acquires salt tolerance through changes to its leaf surface properties, osmotic adjustment, and the regulation of Na+ uptake and distribution in the leaves. [ABSTRACT FROM AUTHOR]

The structures of three multicomponent crystals formed with imidazole‐based drugs, namely metronidazole, ketoconazole and miconazole, in conjunction with trithiocyanuric acid are characterized. Each of the obtained adducts represents a different category of crystalline molecular forms: a cocrystal, a salt and a cocrystal of salt. The structural analysis revealed that in all cases, the N—H...N hydrogen bond is responsible for the formation of acid–base pairs, regardless of whether proton transfer occurs or not, and these molecular pairs are combined to form unique supramolecular motifs by centrosymmetric N—H...S interactions between acid molecules. The complex intermolecular forces acting in characteristic patterns are discussed from the geometric and energetic perspectives, involving Hirshfeld surface analysis, pairwise energy estimation, and natural bond orbital calculations. [ABSTRACT FROM AUTHOR]

The vibrational spectra of the natural ammonium sulfates tschermigite NH4Al(SO4)2(H2O)12, lonecreekite NH4Fe(SO4)2(H2O)12, ammoniovoltaite (NH4)2Fe2+5Fe3+3Al(SO4)12(H2O)18, sabieite NH4Fe(SO4)2, ammonioalunite NH4Al3(SO4)2(OH)6, and ammoniojarosite NH4Fe3(SO4)2(OH)6 were studied to determine the behavior of ammonium in symmetry-inappropriate positions. Disorder of the ammonium cation in salt crystals caused by the need to adjust the tetrahedral cation to the symmetry of the position to preserve the crystal symmetry was revealed. If the symmetry group of the position was not a subgroup of the tetrahedral symmetry group, the NH4 tetrahedron was distorted by the subgroup Hʹ common for Td and H, where H is the symmetry group of the position. Then, a polyhedron corresponding to the symmetry of the position was constructed from N = |H|/|Hʹ| (|H| and |Hʹ| are the orders of these groups) distorted tetrahedra. The disordered ammonium cation had several orientations (N), the superposition of which formally gave a polyhedron corresponding to the local symmetry. The maximum common subgroups for the given salts were C3v and C3. Distortion of ammonium led to activation of ν1 and ν2 [NH4+ ] vibrations in the IR spectrum and splitting of ν3 and ν4 [NH4+ ]. However, the effect was barely noticeable for ammonium in a centrosymmetric position, as in ammonioalunite and ammoniojarosite. The ν4 [NH4+] band was noticeably split and ν1 and ν2 [NH4+ ] vibrations were clearly visible in spectra of the ammonium alums, ammoniovoltaite, and sabieite. [ABSTRACT FROM AUTHOR]

Cementing wells in salt rock is a challenging operation, particularly due to changes in cement properties as a result of interaction with dissolved rock, which can lead to poor cementing quality and risks associated with leakage. In this paper, the effects of NaCl content on the properties of the cement in contact with selected salt rock samples are investigated. The results are suitable for determining the dependencies of cement properties required for the selection of a plugging system formulation suitable for the geological and technical target conditions in well construction. The cement samples were exposed to aqueous NaCl solutions for 28 days after which no significant changes in mechanical properties, such as compressive strength, gas permeability coefficient, expansion/shrinkage and contact strength with the salt rock, were observed. Based on the results, the optimum strength properties of the cement were determined at a saturation coefficient (Kn) between 0.6 and 0.8 where up to 21% increase in the compressive strength was identified possibly due to the formation of strong bondings between the cement and the salt rock. In addition, the growth of salt crystals inside the cement at high concentrations of NaCl was determined through increasing linear dimensions of the cement sample by 2.5% that leads to the formation of microcracks and channels as confirmed by the obtained results of gas permeability tests, namely an increase from 0.38 to 0.91 mD. [ABSTRACT FROM AUTHOR]

Highlights: Inspired by transport system in trees, a two-way water and salt transport mechanism is realized in a structurally graded aerogel, enabling simultaneous fast water uptake and salt rejection. The horizontally aligned pore channels near the surface achieve excellent heat localization by maximizing solar absorption and minimizing heat loss. The integrated water, salt, and thermal transports impart an impressive evaporation rate of 1.94 kg m−2 h−1 in a 20 wt% NaCl solution for 8 h without salt accumulation. Solar-powered interfacial evaporation is an energy-efficient solution for water scarcity. It requires solar absorbers to facilitate upward water transport and limit the heat to the surface for efficient evaporation. Furthermore, downward salt ion transport is also desired to prevent salt accumulation. However, achieving simultaneously fast water uptake, downward salt transport, and heat localization is challenging due to highly coupled water, mass, and thermal transport. Here, we develop a structurally graded aerogel inspired by tree transport systems to collectively optimize water, salt, and thermal transport. The arched aerogel features root-like, fan-shaped microchannels for rapid water uptake and downward salt diffusion, and horizontally aligned pores near the surface for heat localization through maximizing solar absorption and minimizing conductive heat loss. These structural characteristics gave rise to consistent evaporation rates of 2.09 kg m−2 h−1 under one-sun illumination in a 3.5 wt% NaCl solution for 7 days without degradation. Even in a high-salinity solution of 20 wt% NaCl, the evaporation rates maintained stable at 1.94 kg m−2 h−1 for 8 h without salt crystal formation. This work offers a novel microstructural design to address the complex interplay of water, salt, and thermal transport. [ABSTRACT FROM AUTHOR]

Background. The creation of safe and highly effective drugs in pharmacology is relevant. Purpose. Synthesis of molecular complexes of organic salts based on levofloxacin, determination of the structure and crystallographic size. Methodology. The crystal structures of the complex (X Calibur-R Oxford Diffraction) were registered with the corresponding programs, the Hirschfeld surface analysis of the synthesized complex was performed. Originality. The surface analysis of the complex according to Hirschfeld was carried out and the energies of intermolecular interactions were calculated. Findings. A new molecular complex of the salt [LEVH]2∙[S2O6]∙2H2O was obtained. Its molecular characteristics and crystal structure were determined by X-ray structural analysis. [ABSTRACT FROM AUTHOR]

The results of the studies performed at the Shubnikov Institute of Crystallography and devoted to the development of UV optical filters based on complex nickel and cobalt compounds are reviewed. The structural dependence of the optical properties of these crystals and their thermal stability is discussed. The fundamental features of mixed crystals grown from solution and developed approaches to the design of optical filters based on structurally perfect mixed K2(Co,Ni)(SO4)2⋅6H2O crystals are described. The possibility of designing UV-А optical filters by partial substitution of the ligand environment of transition metal ions is demonstrated. [ABSTRACT FROM AUTHOR]

The common technique of traditional salt production in Indonesia is seawater evaporation technology, which uses sunlight to produce salt crystals from seawater. However, in general, the applied technology only produces salt with about 80% NaCl and water contents >7%, impurities >2%, and other contaminants. This produced salt is not suitable to be used as industrial salt. This study aimed to determine the effects of liquid organic fertilizer Gracilaria sp. addition into the culture media of Tetraselmis chuii on Artemia sp. growth, to identify the profile of length, weight, and survival rate of Artemia sp., and finally attempted to uncover the contribution of Artemia sp. in impurity mineral absorption and NaCl content improvement. The results of the study showed that the density of T. chuii based on the concentration of liquid organic fertilizer Gracilaria sp. was significantly different (p<0.05) in each treatment. T. chuii cultivation using liquid organic fertilizer Gracilaria sp. 16 mg N/mL resulted in the highest density on the culture days. However, the studies showed that there was no significant effect (p>0.05) on the weight and length gain of Artemia sp. The research conducted can support the downstream use of products from engineering research in the field of technology to increase the added value of salt products and be part of the contribution to the achievement of the 14th SDG on life below water. [ABSTRACT FROM AUTHOR]

Tuning the lattice spacing or stop bands holds great significance in the design and application of materials with colloidal crystals. Typically, particle surface modifications or the application of external physical fields are needed. In this study, we demonstrated the ability to expand or compress the lattice of colloidal crystals simply by utilizing a salt solution, without the need for any special treatments to the colloidal particles. We found that by only considering the diffusiophoresis effect we cannot explain the reversion of lattice expansion to lattice compression with the increase in the salt concentration and that the diffusioosmotic flow originating from the container wall must be taken into account. Further analysis revealed that variations in the salt concentration altered the relative amplitudes between diffusiophoresis and diffusioosmosis through changing the zeta potentials of the particles and the wall, and the competition between the particle diffusiophoresis and wall diffusioosmosis lay at the center of the underlying mechanism. [ABSTRACT FROM AUTHOR]

Nylon 514 is one of the new long-chain bio-based nylon materials; its raw material, 1,5-pentanediamine (PDA), is prepared by biological techniques, using biomass as the raw material. The high-performance monomer of nylon 514, 1,5-pentanediamine-tetradecanedioate (PDA-TDA) salt, was obtained through efficient crystallization methods. Here, two crystal forms of PDA-TDA, anhydrous and dihydrate, were identified and studied in this paper. From the characterization data, their crystal structures and thermal behaviors were investigated. Lattice energy was calculated to gain further insight into the relationship between thermal stability and crystal structures. The contribution of hydrogen bonds and other intermolecular interactions to the crystal structure stability have been quantified according to detailed Hirshfeld and IRI analyses. Additionally, the transformation mechanism of the anhydrate and dihydrate was established through a series of well-designed stability experiments, in which the temperature and water activity play a significant role in the structural stability of crystalline forms. Eventually, we obtained nylon 514 products with good thermal stability and low absorption using stable dihydrate powders as monomers. The properties of nylon 514 products prepared by different polymerization methods were also compared. [ABSTRACT FROM AUTHOR]

A total of 66 sets of pullout specimens were prepared to investigate the bonding properties of basalt fiber-reinforced polymer reinforcement (hereinafter referred to as BFRP) with seawater sand concrete (hereinafter referred to as SSC). The volume dosages of mono-doped glass fibers and mono-doped polypropylene fibers were 0.1%, 0.2%, and 0.3%; the total volume dosage was set to be constant at 0.3%; and the doping ratios of the hybrid fibers were 1:2, 1:1, and 2:1. The effect on the bonding performance of BFRP reinforcement with SSC was studied on the condition of the diameter D of the BFRP reinforcement being 12 mm; the bond length of SSC being 3D, 5D, and 7D; and the surface characteristics of the reinforcement being sandblasted and threaded. The research showed that due to internal cracks in the matrix, salt crystals in the pores, chloride salts with high brittleness and expansion, as well as sulfate corrosion products such as "Frederick salts" in SSC, the concrete became brittle, resulting in more brittle splitting failures during the pullout test. Doped fibers can increase the ductility effect of concrete, but the bonding effect between the threaded fiber reinforcement and the SSC was not as good as that of the sandblasting group. When the bond length was 5D, the bonding effect between the BFRP reinforcement and SSC was the best, and the bonding performance of the experimental group with doped fibers was better than that of the threaded group. Finally, by combining the ascending segment of the Malvar model with the descending segment of the improved BPE model, a constitutive relationship model suitable for the bond–slip curve between BFRP reinforcement and SSC was fitted, which laid a theoretical foundation for future research on SSC. [ABSTRACT FROM AUTHOR]

Hydrogen can be a critical part of the energy transition and salt caverns have been considered for underground hydrogen storage. Although there have been some successful experiences of hydrogen storage in salt caverns in Europe and the United States, it is essential to exercise caution when selecting caverns for storage to ensure safe operations. This study investigates the relationship between rock heterogeneity and helium diffusion by testing salt-rock cores from the Lotsberg Formation, Alberta, Canada. We characterized salt rock heterogeneity by analyzing the results of X-ray diffraction (XRD) analysis, thin-section microscopy, scanning electron microscopy/energy dispersive X-ray spectrometry (SEM/EDS), and high-resolution CT scans. Then, diffusion tests were conducted using a custom-designed HPHT visualization cell on core samples with different compositions and crystal sizes. The samples in this study were categorized as Lotsberg Salt and Lotsberg Marlstone. Lotsberg Salt mainly consisted of halite with trace amounts of carbonate impurities, while Lotsberg Marlstone comprised halite with a carbonate matrix containing carbonates, clays, quartz, and muscovite. Helium diffusion through pure and intact halite crystals was negligible, and the micro-scale halite crystal boundaries are non-open or poorly unconnected for helium diffusion. Halite samples with macro-scale grain boundaries and carbonate impurities exhibited more interconnected pore networks, resulting in increased rates of helium diffusion. However, the formation of secondary halite veins between grain boundaries can lead to tightly sealed boundaries that have poor connectivity, limiting helium diffusion within the sample. Salt-rock cores with intergranular fractures and unsealed grain boundaries showed accelerated pressure declines, attributed to the preferential diffusion of helium through these fracture and crack pathways. • Gas transport into salt rocks depends on mineralogy, crystal shape and size. • Gas diffusion through intact halite crystals with no discontinuities is negligible. • Salt crystal boundaries and fractures within grains can be the preferential flow paths for Gas diffusion. [ABSTRACT FROM AUTHOR]

Semi-exposed relics within an air–soil system often have earthworks partially buried, leading to moisture migration and substantial salt accumulation. Salt accumulation threatens relic preservation, but destructive sampling is hindered by conservation concerns. We conducted a case study on salt enrichment at K9901 Armour Pit of Emperor Qinshihuang 's Mausoleum Site Museum. Environmental factors and soil salt characteristics were assessed through sampling and monitoring. A relic-soil coupling system was established with a soil column device containing burned bricks. Using 5-TE sensors, water and salinity movement was tracked, and X-ray diffraction analyzed relic salt crystals. The soil column experiment effectively simulated water-salt migration in relics. Salts, like Cl−, NO3−, SO42−, Na+, and Mg2+, concentrated on the soil surface during evaporation. Simulation linked specific salt species to relic ailments. Salt solution from soil migrated to bricks, forming CaSO4 crystals. Results highlight coupling's role in salt-related deterioration and the need to protect it for optimal relic preservation. Findings impact semi-exposed relic conservation, revealing salt accumulation processes and their impact on historical artifacts. [ABSTRACT FROM AUTHOR]

Studies of Rochelle salt crystals such as colemanite (Ca2B6O11.5H2O), which exhibits ferroelectricity below −7 °C, are performed using a modified two-sublattice pseudospin model Hamiltonian. This Hamiltonian model includes terms for phonon anharmonic interactions up to the fourth order. Using this and the dual thermal Green's function, formulations for ferroelectric mode frequencies, permittivity, and loss tangent for colemanite crystals were derived. The model values were fitted to the derivation to obtain the above quantities of thermal variation. The theoretical variations in these quantities were compared with the experimental variations reported by Gavrilova et al. reported to be in good agreement. [ABSTRACT FROM AUTHOR]

In this work, we applied a hydrophilicity-enhanced solid substrate and an alternating laser-ablation data sampling (ALADS) scheme to improve laser-induced breakdown spectroscopy (LIBS) measurement precision and demonstrated the performance in analyzing K, Mg, Ca, and S contained in commercially available edible salt products. Five edible salt products from Australia, Bolivia, France, and South Korea were dissolved in water and a tiny volume of each solution was dropped on the solid substrate, that is, a miniaturized salt pond. After being dried, the residual salt crystals distributed still inhomogeneously, but the homogeneity could be significantly improved in comparison with that from typical drop-and-dry methods. The ALADS scheme was applied to extract three precise measurements from 9798 single-shot LIBS spectra covering the entire salt pond. The measurements obtained by ALADS were found to agree well with one another regardless of the inhomogeneous distribution of salt crystals. As a result, the measurement precision was proved remarkably. Limits of detection for K, Mg, Ca, and S were estimated to be 0.64, 1.7, 14, and 530 mg/kg, respectively, which are enough to analyze those elements contained in salts typically at the level of 100 parts per million (ppm) to ∼3 wt% for the purpose of salt quality assessment. Graphical abstract This is a visual representation of the abstract. [ABSTRACT FROM AUTHOR]

Salt, one of the most commonly consumed food additives worldwide, is produced in many countries. The chemical composition of edible salts is essential information for quality assessment and origin distinction. In this work, a simple laser-induced breakdown spectroscopy instrument was assembled with a diode-pumped solid-state laser and a miniature spectrometer. Its performances in analyzing Mg and Ca in six popular edible sea salts consumed in South Korea and classification of the products were investigated. Each salt was dissolved in water and a tiny amount of the solution was dropped and dried on the hydrophilicity-enhanced silicon wafer substrate, providing homogeneous distribution of salt crystals. Strong Mg II and Ca II emissions were chosen for both quantification and classification. Calibration curves could be constructed with limits-of-detection of 87 mg/kg for Mg and 45 mg/kg for Ca. Also, the Mg II and Ca II emission peak intensities were used in a k-nearest neighbors model providing 98.6% classification accuracy. In both quantification and classification, intensity normalization using a Na I emission line as a reference signal was effective. A concept of interclass distance was introduced, and the increase in the classification accuracy due to the intensity normalization was rationalized based on it. Our methodology will be useful for analyzing major mineral nutrients in various food materials in liquid phase or soluble in water, including salts. [ABSTRACT FROM AUTHOR]

Plants and animals that thrive in arid regions utilize the diurnal changes in environmental temperature and humidity to optimize their water budget by combining water-harvesting mechanisms and morphophysiological traits. The Athel tamarisk (Tamarix aphylla) is a halophytic desert shrub that survives in arid, hypersaline conditions by excreting concentrated solutions of ions as droplets on its surface that crystallize into salt crystals and fall off the branches. Here, we describe the crystallization on the surface of the plant and explore the effects of external conditions such as diurnal changes in humidity and temperature. The salt mixtures contain at least ten common minerals, with NaCl and CaSO4·2H2O being the major products, SiO2 and CaCO3 main sand contaminants, and Li2SO4, CaSO4, KCl, K2Ca(SO4)2·H2O, CaMg(CO3)2 and AlNaSi3O8 present in smaller amounts. In natural conditions, the hanging or sitting droplets remain firmly attached to the surface, with an average adhesion force of 275 ± 3.5 µN measured for pure water. Rather than using morphological features of the surface, the droplets adhere by chemical interactions, predominantly by hydrogen bonding. Increasing ion concentration slightly increases the contact angle on the hydrophobic cuticle, thereby lowering surface wettability. Small amounts of lithium sulfate and possibly other hygroscopic salts result in strong hygroscopicity and propensity for deliquescence of the salt mixture overnight. Within a broader context, this natural mechanism for humidity harvesting that uses environmentally benign salts as moisture adsorbents could provide a bioinspired approach that complements the currently available water collection or cloud-seeding technologies. [ABSTRACT FROM AUTHOR]

This study investigates a salt design principle for aqueous battery electrolytes by combining chaotropic ions, guanidium cations (Gdm) and bis(trifluoromethanesulfonyl)imide anions (TFSI), forming GdmTFSI. This salt's crystal structure was solved via single-crystal X-ray diffraction and characterized using Fourier-transform infrared spectroscopy. Study reveals that GdmTFSI salt disrupts the hydrogen bonding network of aqueous solutions, impacting water reactivity at electrochemical interfaces. [ABSTRACT FROM AUTHOR]

[Display omitted] At ambient conditions, we found salt crystals formed from unsaturated solutions on an iron surface; these salt crystals had abnormal stoichiometries (i.e. Na 2 Cl and Na 3 Cl), and these abnormal crystals with Cl:Na of 1/2–1/3 could enhance iron corrosion. Interestingly, we found that the ratio of abnormal crystals, Na 2 Cl or Na 3 Cl, with ordinary NaCl was relative to the initial NaCl concentration of the solution. Theoretical calculations suggest that this abnormal crystallisation behaviour is attributed to the different adsorption energy curves between Cl−–iron and Na+–iron, which not only promotes Na+ and Cl− adsorbing on the metallic surface to crystallise at unsaturated concentration but also induces the formation of abnormal stoichiometries of Na–Cl crystals for different kinetic adsorption process. These abnormal crystals could also be observed on other metallic surfaces, such as copper. Our findings will help elucidate some fundamental physical and chemical views, including metal corrosion, crystallisation and electrochemical reactions. [ABSTRACT FROM AUTHOR]

Bionic multifunctional structural materials that are lightweight, strong, and perceptible have shown great promise in sports, medicine, and aerospace applications. However, smart monitoring devices with integrated mechanical protection and piezoelectric induction are limited. Herein, we report a strategy to grow the recyclable and healable piezoelectric Rochelle salt crystals in 3D-printed cuttlebone-inspired structures to form a new composite for reinforcement smart monitoring devices. In addition to its remarkable mechanical and piezoelectric performance, the growth mechanisms, the recyclability, the sensitivity, and repairability of the 3D-printed Rochelle salt cuttlebone composite were studied. Furthermore, the versatility of composite has been explored and applied as smart sensor armor for football players and fall alarm knee pads, focusing on incorporated mechanical reinforcement and electrical self-sensing capabilities with data collection of the magnitude and distribution of impact forces, which offers new ideas for the design of next-generation smart monitoring electronics in sports, military, aerospace, and biomedical engineering. Smart monitoring devices with integrated mechanical protection and piezoelectric induction are limited. Here, the authors report a strategy to grow piezoelectric Rochelle salt crystals in 3D-printed cuttlebone-inspired structures to produce smart monitoring devices with integrated mechanical protection and electrical sensing capability. [ABSTRACT FROM AUTHOR]

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Unprecedentedly, crystals of the bis(tetramethylammonium) salt of p-tert-butylcalix[4]arene-1,3-diphosphonic acid, having a preorganized hydrophilic guest recognition space sandwiched by hydrophobic host layers, have been prepared for the selective collection of Yb(III) from 0.01 M HCl solution under thermodynamic control. [ABSTRACT FROM AUTHOR]

Monolayer MoS2 is a two‐dimensional transition‐metal dichalcogenide (TMD), and its atomic‐level thickness makes it an appealing research target in beyond‐silicon devices. Future practical uses are intimately related to controllable synthesis of materials at present, and salt‐assisted chemical vapor deposition (SA‐CVD) offers a promising way. However, the specific growth mechanism of alkali metal salts on MoS2 crystal development and their influence on optoelectronic characteristics of the as‐grown MoS2 crystals is not fully identified. Here, based on large amount experiments, we present a vapor‐liquid‐solid (VLS) edge‐adsorbed growth model for synthesizing MoS2 nanoflakes, emphasizing the edge‐adsorbed phenomena of the alkali metal element Na in regulating MoS2 crystal shape. Through controlling flow rate of carrier gas, the MoS2 defective morphology can be effectively suppressed. This study contributes to a better understanding of the role of alkali metal halide salts in TMD development by providing experimental and theoretical evidence, which is critical for synthesizing high quality TMD by alkali metal halide salts catalyst. [ABSTRACT FROM AUTHOR]

Hypersaline wastewater management is a crucial issue for water‐energy nexus. Evaporation‐based zero liquid discharge (ZLD) desalination shows great promise to detoxify the hypersaline wastewater. However, salt formed on the evaporation surface compromises the efficiency and continuity of desalination. Here, the study reports a photothermal lubricant‐infused surface (PLIS), capable of inducing mobile salt crystallization and eliminating salt scaling during desalination. Few nuclei initiate away from the PLIS, followed by migration inward as salt growth, leading to compact crystal. The final dewetting process leaves only scattered protrusions from crystal bottom contacting with the PLIS. Such a converged small area plus pinpoint contacting mode produce an ultralow adhesion of salt to the substrate (≈2 mN mg−1), ≈40 times lower than that on a regular‐used hydrophobic surface. The salt crystal precipitated on the PLIS can be blown off easily by air flow, refreshing the evaporating surface for continuous desalination and realizing ZLD. [ABSTRACT FROM AUTHOR]

Solid‐state fluorescent materials are in huge demand owing to their potential applications in sensors, imaging, and LEDs. The molecular aggregations in the solid state limit their usage in practical applications. Typically, J‐aggregates show enhanced emission, while H‐aggregates show quenching in the solid state. Few supramolecular approaches (like creating hydrogen bonds) were developed to disturb the π–π and other supramolecular interactions in solid‐state H‐aggregates. Herein, we are reporting a p‐toulenesulfonyl hydrazide derivative of tri(biphenyl‐4‐yl)amine (TBA‐THZ) in the solid state showed negligible emission while grinding with M+X− (M+=alkali and alkali earth metal) salts showed enhanced emission. Existing supramolecular interactions were disturbed by dipole‐ion interactions between S=O⋅⋅⋅M+. The micro/nanometer‐sized salt crystal particles serve as templates for the TBA‐THZ molecules, and in the broad sense, the salt crystal surfaces act as a "solid‐state solvent." The TBA‐THZ ground with various metal salts showed varied emission intensities; the BaCl2 ⋅ 2H2O salt ground sample exhibited the maximum emission intensity. The KPF6+18‐Crown‐6 sample showed 84 times enhanced emission than the pristine TBA‐THZ. The role of 18‐crown‐6 ether was observed as a donor type for K+ ions. The expected S=O⋅⋅⋅K+ dipole‐ion interactions were elucidated through FT‐IR and computational modelling. The slight change in emission wavelength to the higher side after grinding with metal salt indicates that dipole‐ion interactions might slightly modify the chromophore's electronic structure, encouraging radiative decay and higher emission intensity. In contrast, a similar molecule, TBA‐PH, with no sulfonyl functional group, was silent in emission intensity. The TBA‐PH solid has no significant emission even after grinding with metal salts. The emission capacity of the TBA‐THZ salt‐ground powder remained unchanged at higher temperatures and in a highly humid environment. The fluorescent active salt ground matrix of the TBA‐THZ responded admirably to HCl acid fumes and was regenerated upon exposure to ammonia vapours. [ABSTRACT FROM AUTHOR]

The article explains reasons of elongation (0.019 Å) of the bond between iron–cyclopentadienyl ring in the 1,2,4,1',2',4'-hexamethylferricinium (sym. Ме6Fc+ ) cation formed due to the one-electron oxidation of iron atom of sym.1,2,4,1',2',4'-hexamethylferrocene (sym. Ме6Fc) molecule which is 2-2.5 times smaller (0.04–0.05 Å) than that observed in pairs of ferrocene/ferricinium (Fc/Fc+ ), sym. octamethylferrocene/sym.octamethylferricinium (Ме8Fc/Me8Fc+ ) and decamethylferrocene/decamethylferricinium (Ме10Fc/Ме10Fc+ ). For this purpose, X-ray structural parameters characterizing the interaction between cation and anion in the sym.Ме6Fc+PF6 – complex was compared with appropriate parameters in Ме8Fc+BF4 –, Ме10Fc+Br3 and Ме10Fc+PF6 – complexes; and it was mooted that there is an F …H type hydrogen bond in this complex taking into account the length of the non-valent F…H contact (bond) in the sym. Ме6Fc+PF6 – complex. The lengths of Р–F bonds and F–P–F angles of the PF6 – anion in the listed 4 sandwich complexes were compared with appropriate parameters in the РF6 – anion of the LiРF6 crystal. It has been unequivocally proved that F…H hydrogen bonds exist in the sym.Ме6Fc+PF6 – complex. [ABSTRACT FROM AUTHOR]

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This study aims to investigate the potential factors affecting hydraulic fracturing of inter-salt oil shale reservoirs in the Qianjiang Depression, China. Using the inter-salt shale samples, the re-crystallization seepage tests, rock mechanical tests under high temperature and pressure, salt rock creep tests, and direct shear tests were conducted. The testing results suggest several major factors that affect hydraulic fracturing effects in the end. First, the seepage of reservoir and fracturing fluid through hydraulic fractures leads to salt dissolution and crystallization, reducing the effective seepage area of fractures. Second, the salt crystal may block the pore throats or micro fractures after brine invades the shale, decreasing the overall permeability. Third, the low strength and obvious plasticity of inter-salt shale and the strong creep characteristics of salt rock raise difficulties for proppant to effectively support fracture walls, thereby sharply narrowing the hydraulic fracture width. Lastly, the weak interfaces (bedding planes and lithology interfaces) in inter-salt oil shale reservoirs restrict the height of hydraulic fractures, resulting in the disconnection of seepage channels between multiple inter-salt shale reservoirs. Thus, several factors together reduce reservoir permeability, weaken the fluid flow capacity in the fracture, narrow the fracture width, and limit the effective stimulation volume, resulting in weaken the effect hydraulic fracturing. [ABSTRACT FROM AUTHOR]

Based on the unique ubiquity of similar solvate structures found in solvate crystals and superconcentrated electrolytes, we performed a systematic study of four reported solvate crystals which consist of different lithium salts (i.e., LiMPSA, LiTFSI, LiDFOB, and LiBOB) solvated by acetonitrile (MeCN) based on first principles calculations. Based on the calculations, these solvate crystals are predicted to be electronic insulators and are expected to be similar to their insulating liquid counterpart (e.g., 4 M superconcentrated LiTFSI-MeCN electrolyte), which has been confirmed to be a promising electrolyte in lithium batteries. Although the MeCN molecule is highly unstable during the reduction process, it is found that the salt-MeCN solvate molecules (e.g., LiTFSI-(MeCN)2, LiDFOB-(MeCN)2) and their charged counterparts (anions and cations) are both thermodynamically and electrochemically stable, which can be confirmed by Raman vibrational modes through the unique characteristic variation in C≡N bond stretching of MeCN molecules. Therefore, in addition to the development of new solvents or lithium salts, we suggest it is possible to utilize the formation of superconcentrated electrolytes with improved electrochemical stability based on existing known compounds to facilitate the development of novel electrolyte design in advanced lithium batteries. [ABSTRACT FROM AUTHOR]

Avicennia marina , a mangrove plant growing in coastal wetland habitats, is frequently affected by tidal salinity. To understand its salinity tolerance, the seedlings of A. marina were treated with 0, 200, 400 and 600 mM NaCl. We found the whole-plant dry weight and photosynthetic parameters increased at 200 mM NaCl but decreased over 400 mM NaCl. The maximum quantum yield of primary photochemistry (Fv/Fm) significantly decreased at 600 mM NaCl. Transmission electron microscopy observations showed high salinity caused the reduction in starch grain size, swelling of the thylakoids and separation of the granal stacks, and even destruction of the envelope. In addition, the dense protoplasm and abundant mitochondria in the secretory and stalk cells, and abundant plasmodesmata between salt gland cells were observed in the salt glands of the adaxial epidermis. At all salinities, Na+ content was higher in leaves than in stems and roots; however, Na+ content increased in the roots while it remained at a constant level in the leaves over 400 mM NaCl treatment, due to salt secretion from the salt glands. As a result, salt crystals on the leaf adaxial surface increased with salinity. On the other hand, salt treatment increased Na+ and K+ efflux and decreased H+ efflux from the salt glands by the non-invasive micro-test technology, although Na+ efflux reached the maximum at 400 mM NaCl. Further real-time quantitative PCR analysis indicated that the expression of Na+/H+ antiporter (SOS1 and NHX1), H+-ATPase (AHA1 and VHA-c1) and K+ channel (AKT1 , HAK5 and GORK) were up-regulated, and only the only Na+ inward transporter (HKT1) was down-regulated in the salt glands enriched adaxial epidermis of the leaves under 400 mM NaCl treatment. In conclusion, salinity below 200 mM NaCl was beneficial to the growth of A. marina , and below 400 mM, the salt glands could excrete Na+ effectively, thus improving its salt tolerance. [ABSTRACT FROM AUTHOR]

A change in the parameters of electrical switching in an applied magnetic field has been found in a Rochelle salt single crystal. The modified hysteresis loop in the case of switchable polarization implies a deceleration in the motion of ferroelastic domains. The effect is apparently related to the magnetically stimulated enhancement of the domain wall pinning. [ABSTRACT FROM AUTHOR]

The results of comprehensive studies of structural and phase transformations in (K0.43(NH4)0.57)3H(SO4)2 superprotonic crystals under the influence of atmospheric moisture are presented. The real structure, composition, and thickness of the modified surface layers have been analyzed using scanning electron microscopy and X-ray microscopy. The local characteristics of nanostructures, formed on the freshly cleaved (001) crystal surface subjected to the electrostatic effect, have been investigated by conductive atomic force microscopy. A correlation has been established between the time changes in the structure, composition, and magnitude of the electrostatic potential of the crystal surface. The results are considered in the context of evaluation of the chemical stability of the samples and searching for the ways to optimize the compositions and functional properties of superprotonic compounds. [ABSTRACT FROM AUTHOR]

We present a novel technique that elucidates the mechanism of the formation of small aerosolizable salt particles from salty frozen samples. We demonstrated that CsCl may be a suitable probe for sea salts due to its similar subzero properties and sublimation outcomes: CsCl substantially increased the visibility of the salt both during and after ice sublimation. Hence, we identified the factors that, during the sublimation of a frozen salty solution, are important in generating fine salt particles as a possible source of salt aerosol. The number, size, and structure of the particles that remain after ice sublimation were investigated with respect to the concentration of the salt in the sample, the freezing method, and the sublimation temperature. The last-named aspect is evidently of primary importance for the preference of fine salt crystals over a large compact piece of salt; we showed that the formation of small salt particles is generally restricted if the brine is liquid during the ice sublimation, i.e. at temperatures higher than the eutectic temperature (Teu). Small salt particles that might be a source of atmospheric aerosols were formed predominantly at temperatures below Teu , and their structures strongly depended on the concentration of the salt. For example, the sublimation of those samples that exhibited a concentration of less than 0.05 M often produced small aerosolizable isolated particles that are readily able to be windblown. Conversely, the sublimation of 0.5 M samples led to the formation of relatively stable and largely interconnected salt structures. Our findings are in good agreement with other laboratory studies which have unsuccessfully sought salt aerosols from, for example, frost flowers at temperatures above Teu. This study offers an explanation of the previously unexplored behaviour. [ABSTRACT FROM AUTHOR]

The impact of salt crust formation over porous media on water evaporation is an important issue in relation with the water cycle, agriculture, building sciences and more. The salt crust is not a simple accumulation of salt crystals at the porous medium surface but undergoes complex dynamics with possible air gap formation between the crust and the porous medium surface. We report on experiments that allow to identify various crust evolution regimes depending on the competition between evaporation and vapor condensation. The various regimes are summarized in a diagram. We focus on the regime where dissolution–precipitation processes lead to the upward displacement of the salt crust and the generation of a branched pattern. It is shown that the branched pattern results from the crust upper surface destabilization whereas the crust lower surface remains essentially flat. We show that the resulting branched efflorescence salt crust is heterogeneous with a greater porosity in the salt fingers. This leads to the preferential drying of the salt fingers followed by a period in which the crust morphology change only occurs in the salt crust lower region. The salt crust eventually tends toward a frozen state where no visible change occurs in the salt crust morphology, but without blocking the evaporation. These findings provide in-depth insights into the salt crust dynamics and pave the way for the better understanding of the impact of efflorescence salt crusts on evaporation and the development of predictive models. [ABSTRACT FROM AUTHOR]

Poly (triazine imide) photocatalysts prepared via molten salt methods emerge as promising polymer semiconductors with one‐step excitation capacity of overall water splitting. Unveiling the molecular conjugation, nucleation, and crystallization processes of PTI crystals is crucial for their controllable structure design. Herein, microscopy characterization was conducted at the PTI crystallization front from meso to nano scales. The heptazine‐based precursor was found to depolymerize to triazine monomers within molten salts and KCl cubes precipitate as the leading cores that guide the directional stacking of PTI molecular units to form aggregated crystals. Upon this discovery, PTI crystals with improved dispersibility and enhanced photocatalytic performance were obtained by tailoring the crystallization fronts. This study advances insights into the directional assembling of PTI monomers on salt templates, placing a theoretical foundation for the ordered condensation of polymer crystals. [ABSTRACT FROM AUTHOR]

Deliquescence is a first-order phase transition, happening when a salt absorbs water vapor. This has a major impact on the stability of crystalline powders that are important for example in pharmacology, food science and for our environment and climate. Here we show that during deliquescence, the abundant salt sodium sulfate decahydrate, mirabilite (Na2SO4·10H2O), behaves differently than anhydrous salts. Using various microscopy techniques combined with Raman spectroscopy, we show that mirabilite crystals not only lose their facets but also become soft and deformable. As a result, microcrystals of mirabilite simultaneously behave crystalline-like in the core bulk and liquid-like at the surface. Defects at the surface can heal at a speed much faster than the deliquescence rate by the mechanism of visco-capillary flow over the surface. While magnesium sulfate hexahydrate (MgSO4⋅6H2O) behaves similarly during deliquescence, a soft and deformable state is completely absent for the anhydrous salts sodium chloride (NaCl) and sodium sulfate thenardite (Na2SO4). The results highlight the effect of crystalline water, and its mobility in the crystalline structure on the observed softness during deliquescence. Controlled hydrated salts have potential applications such as thermal energy storage, where the key parameter is relative humidity rather than temperature. Crystalline solids are commonly associated with their hard and faceted nature. Here, the authors report the transition from hard to soft and deformable, observed in the gradual dissolution of salt crystals that harbor water in their crystalline framework. [ABSTRACT FROM AUTHOR]

Halite (NaCl mineral) has exhibited the potential to preserve microorganisms for millions of years on Earth. This mineral was also identified on Mars and in meteorites. In this study, we investigated the potential of halite crystals to protect microbial life-forms on the surface of an airless body (e.g., meteorite), for instance, during a lithopanspermia process (interplanetary travel step) in the early Solar System. To investigate the effect of the radiation of the young Sun on microorganisms, we performed extensive simulation experiments by employing a synchrotron facility. We focused on two exposure conditions: vacuum (low Earth orbit, 10−4 Pa) and vacuum-ultraviolet (VUV) radiation (range 57.6–124 nm, flux 7.14 W/m2), with the latter representing an extreme scenario with high VUV fluxes comparable to the amount of radiation of a stellar superflare from the young Sun. The stellar VUV parameters were estimated by using the very well-studied solar analog of the young Sun, κ1 Cet. To evaluate the protective effects of halite, we entrapped a halophilic archaeon (Haloferax volcanii) and a non-halophilic bacterium (Deinococcus radiodurans) in laboratory-grown halite. Control groups were cells entrapped in salt crystals (mixtures of different salts and NaCl) and non-trapped (naked) cells, respectively. All groups were exposed either to vacuum alone or to vacuum plus VUV. Our results demonstrate that halite can serve as protection against vacuum and VUV radiation, regardless of the type of microorganism. In addition, we found that the protection is higher than provided by crystals obtained from mixtures of salts. This extends the protective effects of halite documented in previous studies and reinforces the possibility to consider the crystals of this mineral as potential preservation structures in airless bodies or as vehicles for the interplanetary transfer of microorganisms. [ABSTRACT FROM AUTHOR]

In this paper, we report on the crystal structure of salt 1-(4-bromo-2,3,5,6-tetrafluorophenyl)-3-(3-phenylbenzyl)-4-methylimidazolium bromide, 3, synthesized by the sequential nucleophilic attack of 4-methylimidazole on bromopentafluorobenzene and then 3-phenylbenzyl bromide. The salt was characterized by 1H, 13C, and 19F NMR spectroscopy and mass spectrometry. [ABSTRACT FROM AUTHOR]