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In this study, an innovative hybrid process was proposed and examined as an alternative for nickel/cobalt separation from a synthetic pregnant leach solution. The first step was carried out by employing electrodeionization of a feed solution containing 950 ppm of nickel and 100 ppm of cobalt after adding EDTA to form (Ni-EDTA)−2 complex to suppress migration of nickel cations toward cathodic compartment. This process increased nickel percentage from 90.47 to 97 in the diluted feed solution. This solution was then subjected to cation exchanging process to adsorb the remaining cobalt cations, leading to a nickel purity of 99.7 wt% with an overall recovery 71.1%. On the other hand, the cathode rinse solution of EDI process which contained a major portion of the cobalt cations underwent three stages of extraction process using cyanex 272, resulting in recovery of 65.5 wt% of cobalt with a purity of 100%. It was seen that six stages of solvent extraction process were needed to reach the same purity of cobalt cations by the traditional extraction method. These findings highlight the superior performance of the proposed hybrid process, which not only yielded a relatively high recovery ratio but also ensured excellent purity of nickel and cobalt. [ABSTRACT FROM AUTHOR]

Carrageenans are polysaccharides from red algae which are widely used as food additives and in other applications. Their structure is often described by different disaccharide repeating units, although it was already demonstrated that reality is more complex. In many studies, commercial carrageenans were used to establish structure function relationships, but a structural and compositional analysis was rarely conducted. Therefore, the aim of our study was to systematically and comprehensively characterize a broad collection of commercial carrageenans with different specifications from different manufacturers. For a more detailed characterization, an analytical approach based on partial enzymatic hydrolysis in combination with HPLC–MS and HPSEC-RI was developed and applied. Furthermore, rheology was used to gain detailed insights into the functionality of selected samples. Our results demonstrate that significant structural variation can be observed for commercial carrageenans. The samples contained different cations and the carrageenan type specified by the manufacturer did not always represent the structure of the corresponding polysaccharides. This was especially true for λ-carrageenans: Of the six commercial samples analyzed, none contained structural elements from the λ-type. Instead, the corresponding carrageenans contained κ-, ι- and ν-units. The application of the developed enzymatic-chromatographic approach showed that different hybrid carrageenans are present. In addition, the rheological analysis of the commercial carrageenan samples showed clear differences in the gelling properties upon calcium addition which could influence their behavior in different applications. Our results demonstrate that before an investigation of structure–function relationships, commercial carrageenan samples should be analyzed for their structure and composition. We also showed that the enzymatic-chromatographic approach described in this study is well suited for this purpose. [ABSTRACT FROM AUTHOR]

In this paper, the effect of trace components in dolomite on the morphology of vaterite calcium carbonate is studied in the CaCl2‐NH3‐CO2 system, with a focus on the effect of cations (Mg2+, Fe3+, Si4+, and Al3+) in the solution. Ca2+, NH4+, Mg2+, Fe3+, Si4+, and Al3+ in the digestion solution are proportionally prepared into a solution by analyzing the calcium rich digestion solution which is obtained by digesting dolomite with ammonium chloride solution. Under the optimal conditions, NH3 is introduced at a rate of 0.5 L min−1 for 1 h, CO2 is introduced at a rate of 0.5 L min−1 for 1 h and rotation speed of 500 r min−1 to prepare the vaterite calcium carbonate. The results show that the addition of Mg2+, Fe3+, Si4+, and Al3+ can promote the growth of vaterite calcium carbonate. Among them, adding Mg2+ and Si4+ can promote the dispersion of vaterite, Fe3+ and Al3+ can cause agglomeration of vaterite. Material Studio software is used to predict the crystal morphology of vaterite calcium carbonate under ideal conditions, and the calculation results are basically consistent with the experimental results. [ABSTRACT FROM AUTHOR]

The title compound [systematic name: 1,10-phenanthrolinium 6-hy­droxy-5-(oxido­imino)-1,3-diazinane-2,4-dione–6-hy­droxy-5-(hy­droxy­imino)-1,3-diazin­ane-2,4-dione–water (1/1/5)], C12H9N2+·C4H2N3O4−·C4H3N3O4·5H2O, is a co-crystal salt hydrate comprising 1,10-phenanthrolinium cations, violurate anions, free violuric acid as co-former and five water mol­ecules of crystallization per formula unit. The violurate and the violuric acid residues each form distinct N—H⋯O hydrogen-bonded tapes with a common R²2(8) hydrogen-bond motif extending parallel to (103 ̅ ̅). Solvent water mol­ecules connect the tapes to form a tri-periodic hydrogen-bonded network with channels extending parallel to the a-axis direction, which accommodate the N—H⋯Owater hydrogen-bonded 1,10-phenanthrolinium cations. Direct N—H⋯O hydrogen bonds between the 1,10-phenanthrolinium and violurate ions are not encountered. [ABSTRACT FROM AUTHOR]

TRPM8 is a non-selective cation channel that is expressed in several tissues and cells and also has a unique property to be activated by low-temperature. In this work, we have analyzed the conservation of amino acids that are present in the lipid-water-interface (LWI) region of TRPM8, the region which experiences a microenvironment near the membrane surface. We demonstrate that the amino acids present in the LWI region are more conserved than the transmembrane or even full-length TRPM8, suggesting strong selection pressure in these residues. TRPM8 also has several conserved cholesterol-binding motifs where cholesterol can bind in different modes and energies. We suggest that mutations and/or physiological conditions can potentially alter these TRPM8-cholesterol complexes and can lead to physiological disorders or even apparently irreversible diseases such as cancer and neurodegeneration. [ABSTRACT FROM AUTHOR]

Multinuclear heterometallic oxo clusters, composed of two or more different metal cations bridged by oxo ligands, represent an important class of molecular complexes known for their unique magnetic, catalytic, and electrochemical properties resulting from cooperative interactions between the metal cations. If three or more types of metal cations can be arranged as designed, their chemical and physical properties can be precisely and flexibly controlled, potentially creating innovative materials. However, research on hetero‐trimetallic and hetero‐tetrametallic oxo clusters remains limited. This review presents an interdisciplinary search of multinuclear heterometallic oxo clusters, regardless of the type of ligand, to explain and classify their synthesis strategies and structures. By cataloging crystallographically characterized heterometallic oxo clusters using ligand‐per‐metal values and synthesis method notations, valuable insights have been gained into effective synthesis methods for the precise arrangement of metal cations. The advantages and disadvantages of one‐pot synthesis methods and synthesis strategies for achieving precise structural control of heterometallic oxo clusters are discussed with an emphasis on the prediction of their final structures. The insights from this review are expected to drive the development of synthetic and analytical techniques for the precise synthesis of heterometallic complexes in a predictable way. [ABSTRACT FROM AUTHOR]

Liquid‐solid triboelectric nanogenerator (LS‐TENG) harvests energy efficiently while eliminating wear issues associated with solid‐solid TENG. However, the effect of ions or charges in the liquid on output performance needs further examination. In this work, the impact of fluorine and copper ions introduced through deionized water with sodium fluoride (DI‐NaF) and deionized water with copper sulfate (DI‐CuSO4) solution on the output voltage, charge and current of a tubular LS‐TENG with polytetrafluoroethylene (PTFE) and Nylon as solid materials is examined. The results indicate that fluorine and copper ions have opposite effects on PTFE and Nylon LS‐TENG's output. The fluorine (F−) ions enhance the triboelectric effect and charge transfer in Nylon LS‐TENG, increasing output, while they hinder the charge transfer process in PTFE LS‐TENG, consequently decreasing its output. Conversely, the copper (Cu2+) ions have a positive effect on the output of PTFE LS‐TENG and a detrimental effect on Nylon LS‐TENG's output. Moreover, the results indicate that LS TENG's output performance depends on the charges of solid and liquid triboelectric materials. Thus, this study provides insights into material‐ion interaction in LS‐TENG and underscores the importance of triboelectric material selection for optimizing output performance. [ABSTRACT FROM AUTHOR]

The article discusses the definition of "molecular ion" in mass spectrometry, critiquing the current IUPAC definition as semantically misleading and biased. The authors propose an extended, more inclusive definition that encompasses various subclasses of ions formed from intact molecules. They argue against the use of terms like "quasimolecular ion" and advocate for a more contemporary and collective approach to defining molecular ions. The proposed definition aims to eliminate confusion and ambiguity in describing different types of ions generated by modern mass spectrometry methods. [Extracted from the article]

On the basis of field research, the current state of soils in the eastern zone of the Republic of Kalmykia was studied. The predominant soil cover in this area is represented by brown saline soils and brown-desert soils in a complex with salt licks. The purpose of the study is to study the absorption complex, as well as the composition and content of exchangeable cations in the soils of the eastern zone of the Republic of Kalmykia. cations: calcium (Ca2+) and magnesium (Mg2+) and an assessment of the level of soil absorption capacity in 7 settlements of the Yashkul district of the Republic of Kalmykia. To conduct the research, 15 monitoring sites were placed on the borders and in the center of settlements, the background sample was taken at a distance of 500 m from the boundaries of the residential zone. The determination of the physical and chemical properties of the soils was carried out according to GOST and generally accepted methods. The results of the study showed that the level of absorption capacity of soils in the study area ranges from low to medium. The absorbent complex is saturated with the cations Ca2+ and Mg2+, and the content of exchangeable Ca2+ predominates over the content of Mg2+ in the range of 2 to 4 times. [ABSTRACT FROM AUTHOR]

Chemical ionization in combustion systems forms concentrated ions of both polarities. Applying electric fields and plasmas to combustion systems has been shown to reduce emissions (such as particulate matter) potentially by controlling the ionic properties. Detailed flame-generated ion properties need to be characterized to better understand and predict the dynamics and roles of these ions in combustion and particle formation processes. In this work, we used a high-resolution differential mobility analyzer (HR-DMA) to map the mobility and size distributions of positive and negative ions generated from a premixed methane-air flat flame under atmospheric pressure. Measurements were conducted over a wide range of stoichiometric ratios (0.8 to 1.2) and heights above the burner (HAB, 7–42 mm). Positively charged ions are relatively stable over the entire range of experimental conditions, showing two major modes, one at 1.16 nm, and another at 1.42 nm. The mode corresponding to 1.42 nm showed a gradual increase in size with HAB, indicating the charging of hydrocarbon precursors. With the mobility values of the ions, we calculated their approximate mass values based on the empirical mobility–mass relationship and estimated the charging characteristics of particles in the flame. The ion profiles and particle charging characteristics obtained in this study will improve our understanding of electrostatic interactions in flame systems. [ABSTRACT FROM AUTHOR]

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Copyright of China Pulp & Paper is the property of China Pulp & Paper Magazines Publisher 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.)

Wildfires in the western U.S. have increased in severity and duration in recent decades. Severe wildfires can enhance the rates of nutrient mineralization, causing large exports of inorganic nitrogen and other ions from forests to streams. Measuring the degree to which streams respond to severe, stand-replacing wildfires is critical to estimate in ecosystems prone to disturbance. In 2003, two severe crown wildfires burned in Yellowstone National Park, WY, USA. We studied the extent to which these fires increased nitrogen (ammonium, nitrate and nitrite), sulfate, chloride, and total dissolved phosphorus concentrations and export in three watersheds prior to and during the first four years post-fire. We measured higher concentrations of most ions after wildfire, and nitrate and chloride concentrations increased the most, increasing > 1000 µg/L. Concentrations of nitrate (≤146 times pre-fire concentrations), total dissolved nitrogen (≤11 times), chloride (≤9 times), and total dissolved phosphorus (≤7 times) were higher four years post-fire than before the wildfires burned. Exports of nitrate (≤1392 times), sulfate (≤14 times), and chloride (≤37 times) were also higher after wildfire, while nitrite (≤2.9 times) and ammonium (≤6.4 times) increased to a lesser degree. Stream concentrations of most ions were higher in watersheds that had a larger percent of the area burned. Comparing ion concentrations in streams before and after severe wildfires provides critical information to managers as the climate warms and the frequency of fire-conductive weather increases. [ABSTRACT FROM AUTHOR]

The performance of many known fluorescent sensors for Ca2+ is pH‐dependent. We set out to address this by preparing a novel calcium sensor based on diacylated 1,10‐diaza‐18‐crown‐6 and containing no basic centres. The sensor is sensitive to sub‐millimolar levels of Ca2+ and partially tolerant of an aqueous environment. However, it suffers from a lack of selectivity over some other divalent cations, and retained pH sensitivity in the acidic range. The relations between these properties and the sensor's structure are discussed. [ABSTRACT FROM AUTHOR]

Wildfires in the western U.S. have increased in severity and duration in recent decades. Severe wildfires can enhance the rates of nutrient mineralization, causing large exports of inorganic nitrogen and other ions from forests to streams. Measuring the degree to which streams respond to severe, stand-replacing wildfires is critical to estimate in ecosystems prone to disturbance. In 2003, two severe crown wildfires burned in Yellowstone National Park, WY, USA. We studied the extent to which these fires increased nitrogen (ammonium, nitrate and nitrite), sulfate, chloride, and total dissolved phosphorus concentrations and export in three watersheds prior to and during the first four years post-fire. We measured higher concentrations of most ions after wildfire, and nitrate and chloride concentrations increased the most, increasing > 1000 µg/L. Concentrations of nitrate (≤146 times pre-fire concentrations), total dissolved nitrogen (≤11 times), chloride (≤9 times), and total dissolved phosphorus (≤7 times) were higher four years post-fire than before the wildfires burned. Exports of nitrate (≤1392 times), sulfate (≤14 times), and chloride (≤37 times) were also higher after wildfire, while nitrite (≤2.9 times) and ammonium (≤6.4 times) increased to a lesser degree. Stream concentrations of most ions were higher in watersheds that had a larger percent of the area burned. Comparing ion concentrations in streams before and after severe wildfires provides critical information to managers as the climate warms and the frequency of fire-conductive weather increases.

Early Mars was likely habitable, but could life actually have started there? While cellular life emerged from prebiotic chemistry through a pre-Darwinian selection process relevant to both Earth and Mars, each planet posed unique selection 'hurdles' to this process. We focus on drivers of selection in prebiotic chemistry generic to Earth-like worlds and specific to Mars, such as an iron-rich surface. Iron, calcium, and magnesium cations are abundant in hydrothermal settings on Earth and Mars, a promising environment for an origin of life. We investigated the impact of cations on the stability and disruption of different primitive cell membranes under different pH conditions. The relative destabilizing effect of cations on membranes observed in this study is Ca2+ > Fe2+ > Mg2+. Cation concentrations in Earth systems today are too low to disrupt primitive membranes, but on Mars concentrations could have been elevated enough to disrupt membranes during surface dehydration. Membranes and RNA interact during dehydration-rehydration cycles to mutually stabilize each other in cation-rich solutions, and optimal membrane composition can be 'selected' by environmental factors such as pH and cation concentrations. We introduce an approach that considers how life may have evolved differently under the Martian planetary conditions and selective pressures.

This is the third article in a series that investigates permanent charge effects on ion fluxes involving three ion species with two cations of different valences and one anion. Based on a quasi-one-dimensional classical Poisson-Nernst-Planck model, we analyze and propose a plausible universality of permanent charge effects as a counterpart of the recently established universality for two ion species. The new results in this paper are complement to those in previous two papers in this series, more precisely, previous results explore specifics in the sense that effects of permanent charges on ionic flows (in terms of flux ratios) can be qualitatively different, depending on boundary conditions, while the result in this paper establishes a universal property of permanent charge effects, independent of boundary conditions (under some conditions). This new result is unique and is a necessary component for a comprehensive understanding of basic roles of permanent charges on ionic flows. We hope and believe that these studies of ionic movement dynamics could present concrete properties and insights to stimulate investigations of dynamics of general electrodiffusion. [ABSTRACT FROM AUTHOR]

The fluid description is widely used for the multi-dimensional modeling of low temperature plasmas with complex chemistries due to their relative low computational cost. It relies, however, on a series of simplifying assumptions and some truncation of the moment equations for describing the non-equilibrium between the electrons, positive ions, negative ions, and the neutrals. In this paper, the classical assumption of isothermal negative ions is revisited for electronegative plasmas and, more particularly, for the fluid modeling of the transition between the plasma and its sheath. To do so, and in contrast to previous studies, the energy balance equation for the negative ions is also computed, and it allows us to derive the polytropic coefficient γ of the negative ions in addition to one of the positive ions. Strong variations in the sheath and presheath of the negative ions temperature and their polytropic coefficient are observed. The polytropic coefficient is shown to be a strongly varying function of space having for consequence that the negative ions are isothermal only in a very narrow extension of the presheath. For the case considered in this paper, both positive and negative ion flows are nearly adiabatic at the sheath-edge and become adiabatic inside the sheath. This paper shows that classical fluid modeling assumptions need to be verified for each system under consideration, most particularly while modeling the transition from plasma to a wall. [ABSTRACT FROM AUTHOR]

High-power lasers are routinely used to generate energetic positively charged ions, and this paper reports on the observation of negative ions in these experiments. A large number of negative ions and neutral atoms at MeV energies was obtained from the interaction of a high intensity laser pulse with a water spray along with positive ions [Abicht et al., Appl. Phys. Lett. 103, 253501 (2013)]. Beams of negative ions and neutral atoms have the same properties as beams of positive ions. However, the mechanism of negative ion formation and acceleration is still under discussion. In order to gain more information about physics of generation negative ions and neutrals, we present a new experiment where all species, positive, negative ions, and neutrals, are spatially separated, and the electron capture and loss of each in water spray is evaluated. The formation of negative ions and neutral atoms of hydrogen and carbon with energies up to 140 keV and 1.2 MeV, respectively, is confirmed. It is suggested that the electrification of spray droplets plays a decisive role in these charge-exchange processes. [ABSTRACT FROM AUTHOR]

Cation exchange is a versatile post-synthetic method to explore a wide range of nanoparticle compositions, phases, and morphologies. Recently, several studies have expanded the scope of cation exchange to magic-size clusters (MSCs). Mechanistic studies indicated that MSC cation exchange undergoes a two-stage reaction pathway instead of the continuous diffusion-controlled mechanism found in nanoparticle cation exchange reactions. The cation exchange intermediate, however, has not been well-identified despite it being the key to understanding the reaction mechanism. Only indirect evidence, such as exciton peak shifts and powder x-ray diffraction, has been used to indicate the formation of the cation exchange intermediate. In this paper, we investigate the unusual nature of cation exchange in nanoclusters using our previously reported CdS MSC. High-resolution mass spectra reveal two cation exchanged reaction intermediates [Ag2Cd32S33(L) and AgCd33S33(L), L: oleic acid] as well as the fully exchanged Ag2S cluster. Crystal and electronic structure characterizations also confirm the two-stage reaction mechanism. Additionally, we investigate the Cu/CdS MSC cation exchange reaction and find a similar two-stage reaction mechanism. Our study shows that the formation of dilutely exchanged intermediate clusters can be generally found in the first stage of the MSC cation exchange reaction. By exchanging different cations, these intermediate clusters can access varying properties compared to their unexchanged counterparts. [ABSTRACT FROM AUTHOR]

Soil salinity is a growing problem for agricultural production in irrigated areas of arid and semi-arid regions. The extent of salinity levels has not been fully studied in the Kesem irrigation scheme in Ethiopia's Afar region. The objective of the study was to identify the main issues related to soil salinity and their variations, and to assess the influence of environmental variables on soil salinity using multivariate analysis (MVA). The dominant cations in the soil were found to be soluble Na+, Ca2+ and K+ while SO42-and Cl- were the dominant anions. These ions are responsible for the salinity in the scheme. Groundwater table surveys showed that cultivated fields experienced greater fluctuations in groundwater levels compared to abandoned land due to frequent irrigation. The first two principal components (PCA) explained approximately 60% and 63% of the total variation in salinity for the top and bottom layers, respectively. The difference between the top and bottom layers suggests a management influence. According to redundancy analysis (RDA), the groundwater depth and length of irrigation years were identified as the major environmental factors contributing to 99% and 52% of the variability in salinity, respectively. These findings highlight the importance of considering the rising groundwater levels in future land management decisions.

Cyan-emitting phosphors are urgently needed to address the "cyan gap" in artificial full-spectrum lighting. In this research, a series of Sr(2−y)BayY4La4(SiO4)6O2:xEu2+ (0.005 ≤ x ≤ 0.08, 0.0 ≤ y ≤ 2.0) phosphors with tunable luminescence was synthesized. Through cation regulation, the luminescence color of Sr(2−y)BayY4La4(SiO4)6O2:xEu2+ can be adjusted from yellow to cyan. Crystal structure analysis revealed that Eu2+ ions simultaneously occupy [Sr1/Ba1Y1La1] and [Sr2/Ba2Y2La2] sites, resulting in multiple luminescence centers and a broadened emission spectrum. With increasing Ba2+ ion concentration, the PLE spectrum was red-shifted from 337 nm to 372 nm, and the excitation intensity in the violet region was significantly enhanced, making it more compatible with violet LED chips. Meanwhile, the PL spectrum was blue-shifted from 543 nm to 496 nm with increasing Ba2+ concentration, accompanied by an increase of about 10 times in the excitation and emission intensity. The optimized Ba2Y4La4(SiO4)6O2:0.02Eu2+ phosphor can be excited by violet light and emits bright cyan light effectively, which can be used to fill the "cyan gap". Eventually, a series of white LED devices was manufactured by combining the as-prepared luminescence-tunable phosphors with commercial phosphors. Among them, the 410 nm violet LED chip-based WLED(Ba2) device comprising Ba2Y4La4(SiO4)6O2:0.02Eu2+ exhibited the best electroluminescence performance, increasing the color rendering index from 82.0 to 98.6, verifying the compensation effect of the Ba2Y4La4(SiO4)6O2:Eu2+ phosphor on cyan light. [ABSTRACT FROM AUTHOR]

In a recent Communication in this journal, Bandyopadhyay and co‐workers proposed a rational design of chalcone photoswitches that are claimed to convert into the respective flavylium cations upon irradiation with blue, green, and red light in aqueous media. Here we argue that the reported improvements on the optical/photochemical properties of the new chalcone photoswitches are not substantiated and that the proposed design and data interpretation rely on assumptions that have yet to be validated. We also identify a series of control experiments that can be performed to verify the hypotheses and better support the conclusions presented by the authors. [ABSTRACT FROM AUTHOR]

The cascade carbon–carbon and carbon–nitrogen bond formation between in situ generated carbonyl ylides and azaoxyallyl cations, facilitated by Rh-catalysis and a base, has been achieved to furnish oxa-benzo[c]azepin-3-ones. Substrate scope, functional group diversity, scale-up and post-synthetic utilities are the important practical features. [ABSTRACT FROM AUTHOR]

Nickel-rich layered oxides are one of the most promising positive electrode active materials for high-energy Li-ion batteries. Unfortunately, the practical performance is inevitably circumscribed by the structural deterioration deriving from the Ni/Li antisite disorder, leading to severe capacity loss and life attenuation. Herein, we propose an economical and facile rejuvenation strategy by employing the magneto-electrochemical synergistic activation targeting the positive electrode in assembled Li-ion batteries. This approach induces a transition of Ni3+ from high-spin to low-spin, reducing the super-exchange interaction of Ni-O-transition metal (TM). Meanwhile, electrochemical reaction drives Li+ from the host material and promotes Ni3+ to reoccupy TM layer, recovering intrinsic Li site and extending cycle life. The strategy demonstrates that low-quality positive electrodes can be converted to high-quality ones. Notably, the method can revitalize an aged Li-ion pouch cell (SiC||NCM811, 8 Ah nominal capacity) via optimizing cation occupancy and increase its capacity by 10% from 6.49 to 7.14 Ah at 1 C, illustrating the benefits of the upcycling process. Severe Ni/Li antisite disorder in nickel-rich layered oxides leads to structural degradation and performance decay in Li-ion batteries. Here, authors report a noninvasive strategy of magnetoelectrochemical synergistic activation to realize ordered cation rearrangement and recovery battery capacity. [ABSTRACT FROM AUTHOR]

In this work, we report a rare ionic covalent organic framework (named as ECUT-iCOF-5) synthesized by the Knoevenagel reaction using an ionic liquid monomer. ECUT-iCOF-5 is found to show a promising potential for gold extraction with a high extraction ability towards gold, including a high extraction capacity (3260 mg g−1), good selectivity over both cations and anions, and good recycle use (at least six times). [ABSTRACT FROM AUTHOR]

The single H-bond capable N-H in triethylammonium triggers massive structural rearrangement in an inert Co(III) complex that tetraethylammonium cannot. The rearrangement provides a new way to distinguish two similar cations spectroscopically. The process is identical and instantaneous with labile iron(III) without any spectroscopic change. [ABSTRACT FROM AUTHOR]

ABSTRACT The study investigates the relaxation of a three‐component dusty plasma in the lunar atmosphere. By employing Ampère's law with momentum balance equation of the plasma species, which includes an electron, a positive ion, and a negatively charged dust particle, a Triple Beltrami (TB) state is obtained. This TB state is characterized by three scale parameters, which may be real or complex. The Cartesian coordinate geometry is employed to analyze the magnetic field profiles. The Beltrami parameters, mass of negative charged dust particulates and density variations at different height and angle have a significant impact on the magnetic properties of the self‐organized structures in lunar atmosphere. The study reveals that all scale parameters associated with diamagnetic structures are real and complex, while all scale parameters for paramagnetic structures are real. It has been shown that the magnetic field, along with its complex conjugate and real part, increases with height and angle, and only diamagnetic structures are formed in the lunar atmosphere. The findings of this study should help to explain relaxed structures found in other astronomical objects and in lab settings including negatively charged dust particles, ions, and electrons. [ABSTRACT FROM AUTHOR]

Structurally constrained, cationic PIII compound [LP][SbCl4] with an OCO pincer‐type ligand (L) having a central carbene donor was directly synthesized via an Sb‐to‐P metathesis reaction between PCl3 and LSb‐Cl. [LP][SbCl4] was isolated and its reactivity with small molecules (ROH and RNH2) was studied, showing that [SbCl4]− is not an innocent counter anion, but an active participant in these reactions. When the [SbCl4]− was replaced with the [CB11H12]− ([Cb]−) anion, the reactions were redirected to [LP]+ cation only. The reactions with alcohols and amines led to the equilibrium between the products of the formal E−H (E=O, N) bond oxidative addition to the P‐center and products of the P‐center/ligand‐assisted bond activation. Remarkably, [LP]+ activated the PhO−H and PhN(H)−H bonds in a reversible, thermoneutral fashion. [ABSTRACT FROM AUTHOR]

The doping of photocatalytic La5Ti2AgO7S5 particles with aliovalent metal cations was investigated. The incorporation of lower-valence Al3+ cations at Ti4+ sites improved the photocatalytic hydrogen evolution activity. In addition, the anodic photocurrent during oxygen evolution was increased upon adding higher-valence Ta5+ ions. The effect of doping on the carrier density in the photocatalytic particles was also examined in this work. [ABSTRACT FROM AUTHOR]

Besides excellent thermoelectric properties, composed of earth-abundant elements and featuring simple chemical compositions are more conducive to the practical fabrication and utilization of thermoelectric materials. In this study, a tellurium-free thermoelectric compound, AgSbSe 2 , was synthesized, and the impact of Ag deficiencies on its thermoelectric performance was examined. It was found that the density of charge carriers of AgSbSe 2 can be effectively modulated by introducing slight Ag deficiencies, thereby significantly optimizing its electrical transport performance. A peak power factor of 6.63 μWcm−1K−2 @623 K is achieved in the sample with a composition of Ag 0.99 SbSe 2 , which is similar to the maximum value observed in Pb doped samples prepared by the same experimental production. Meanwhile, extremely low thermal conductivity was restrained in AgSbSe 2 with Ag deficiencies due to the effect of phonon scattering caused by crystal defects, which offsets the increased electrical thermal conductivity. Finally, a maximum zT value of 0.97 @623 K is obtained for Ag 0.99 SbSe 2 , which is comparable to that of heavily doped AgSbSe 2 with the conventional divalent cations doping at the Sb site. [ABSTRACT FROM AUTHOR]

Vinyl cations were first proposed as reactive intermediates nearly eighty years ago by Jacobs, and their properties were closely studied in the second half of the twentieth century by Stang, Olah, Caple, Grob, Hanack, and others. Recent developments in the catalytic generation and reactions of vinyl cations with unactivated C(sp3) −H bonds prompted us to assemble a field guide based on our previous experiences that is geared for synthetic chemists who are looking to construct C−C bonds via vinyl cation C−H insertion or Friedel‐Crafts addition. In particular, this article focuses on silylium‐ and lithium‐initiated C−C bond forming reactions of vinyl cations generated from vinyl triflates and ultimately aims to provide the reader with context and accelerate their selection of optimal reaction conditions and starting materials. [ABSTRACT FROM AUTHOR]

This manuscript describes a study of diverse reaction outcomes that stem from the ionization of aza‐alkynyl‐Prins adducts. Experimental results have demonstrated unexpected behavior in the nitrogen‐containing systems compared to the analogous oxygen derivatives derived from oxa‐Prins/halo‐Nazarov sequences. In‐depth experimental studies and computational analysis revealed an intricate mechanism involving competing halo‐Nazarov and imino‐Nazarov pathways. These findings further elucidate the reaction chemistry of 3‐halo‐pentadienyl cation intermediates, and expand their utility in synthetic transformations. [ABSTRACT FROM AUTHOR]

Yttrium-based metal–organic frameworks built on hexanuclear clusters (Y6-MOFs) represent an important subgroup of MOFs that are assembled from Y6 clusters and diverse organic linkers, featuring a variety of topologies. Due to the robust Y–O bonds and high connectivity of hexanuclear SBUs, Y6-MOFs are generally thermally stable and resistant to water. Additionally, their pore structures are highly tunable through the practice of the reticular chemistry strategy, resulting in excellent performance in gas adsorption and separation related applications. Y6-MOFs are structurally analogous to Zr6-MOFs; however, the existence of charge-balancing cations in Y6-MOFs serves as an additional pore structure regulator, enhancing their tailorability with respect to pore shape and dimensions. In this Frontier article, we summarize the main advances in the design and synthesis of Y6-MOFs, with a particular focus on the precise engineering of their pore structure for gas separation. Future directions of research efforts in this field are also discussed. [ABSTRACT FROM AUTHOR]

The inherent structural flexibility and chiroptical activity of 2D chiral perovskites make them promising for the nonlinear optical (NLO) application. A comprehensive understanding of the second‐harmonic generation (SHG) mechanism in 2D chiral perovskites is essential for developing NLO devices. However, the rational design of 2D chiral perovskite structures to regulate SHG properties remains challenging. Herein, to regulate SHG response, an achiral organic spacer cation alloying strategy is employed to construct a series of 2D chiral perovskites. Through the measurement of temperature‐dependent photoluminescence (PL) spectra, it is revealed that the material design strategy can effectively modulating self‐trapped exciton (STE) emission. More importantly, it is confirmed that there is a competitive relationship between STE emission and SHG in 2D chiral perovskites. Meanwhile, the microscopic imaging of circularly polarized‐SHG is demonstrated in chiral perovskites. This work will not only advance the understanding of the SHG mechanism in 2D chiral perovskites but also provide inspiration for the rational design and synthesis of perovskites for NLO devices. [ABSTRACT FROM AUTHOR]

The development of new π‐conjugated motifs opens pathways to previously unexplored classes of organic semiconductors and functional dyes. In this study, five‐ and seven‐membered carbocycles were fused at the ortho and bay regions of electron‐deficient perylenes, starting from a common dialdehyde precursor. Structural analysis of the resulting perylene tetraesters, dianhydrides, and diimides (PDIs) revealed three distinct ring‐fusion patterns and defined stereochemistry. The fused PDI cycloheptatrienes demonstrated susceptibility to acid‐catalyzed transarylation, involving tropylium cation intermediates, which can be used preparatively. Under superacidic conditions, the PDI tropylium cations were directly observed and shown to undergo hydride‐transfer reductions. Additionally, a fused PDI bis(heptafulvene) was synthesized by dehydrogenating a suitably substituted PDI cycloheptatriene. The final system contains two quinomethane units, which can be protonated to yield a stable tropylium‐like dication. [ABSTRACT FROM AUTHOR]

Multistability on the molecular scale level required for molecular devices can be realized using metallocomplexes with redox-active ligands such as o-quinones, o-quinoneimines and o-diimines as building blocks. Herein, we prepared four sterically shielded di-o-quinones bridged with a dioxyarylene linker with different topology and steric characteristics and studied the properties of their reduced species. EPR spectroscopy investigation revealed that the intramolecular exchange interaction between paramagnetic centers in the biradical dianion derivatives of synthesized di-o-quinones predominantly depends on the steric environment of the linker and the nature of the counter cation at the dioxolene site, and the topology of the linker plays a secondary role. [ABSTRACT FROM AUTHOR]

A robust MOF with diethylammonium cations in its pores, enhances pore partitioning and modifies the environment, enabling selective and dense SO2 packing through hydrogen bonds. It achieves a reversible SO2 uptake with a high adsorption enthalpy and record IAST selectivity of 1182 for SO2/CO2 at 298 K and 1 bar. [ABSTRACT FROM AUTHOR]

Despite a bicentennial history, the interest in polyiodides and related systems still flourishes. The chemical puzzle provided by the intricate nature of chemical bonding in these polyanions remains challenging these days. The advent of the halogen bond and the spreading interest in supramolecular interactions of halogen-based systems promoted further recent interest. Research in the area of materials, where local bonding details eventually result in desired macroscopic properties, provided a further boost. Herein, we illustrate the consequences of contemplating a different bonding scheme for polyiodides, one making explicit use of electron-deficient multicenter bonds (EDMBs), an emerging concept in this area. We present a reinterpretation of polyiodide bonding using a revised approach to the Lewis dot formulas, leading to a clearer pen-and-paper understanding of their bonding. The model is general and can be applied to other related problems (here polyiodonium cations, and other homo- and hetero-polyhalides). Our alternative narrative has a few interesting consequences on several traditional and currently hot topics, including the nature of basic building blocks for polyiodides, hypervalency vs. hypercoordination, the distinction between covalent bonds and supramolecular interactions, and the nature of secondary and halogen bonds. [ABSTRACT FROM AUTHOR]

The lycid genus Ochinoeus, Kubecek, Bray & Bocak, 2015 is reviewed. The genus originally contained four species, three of which are from China: O. hainanensis Kubecek, Bray & Bocak, 2015, O. habashanensis Kubecek, Bray & Bocak, 2015, and O. xunyanbaensis Kubecek, Bray & Bocak, 2015. In this study, three new species are described from China, including O. guangxiensis sp. n., O. yunnanus sp. n., and O. xizangensis sp. n. All of the Chinese Ochinoeus species are illustrated with macrophotographs of their habitus and aedeagi. In addition, a distribution map and identifi cation key to males of all species of Ochinoeus are provided. [ABSTRACT FROM AUTHOR]

Anionic coordination frameworks stabilized by methylviologen (MV2+; 1,1′-dimethyl 4,4′-bipyridinium) as a photochromic module are a distinct class of functional materials. Herein, we report the first examples of alkaline earth metal methanesulfonates [MV{Mg(OSO2Me)3(H2O)2}2] (1), [MV{Ca(OSO2Me)3(H2O)2}2] (2), [2{Mg(OSO2Me)2(H2O)4}MV·2OSO2Me] (3), and [Me4-pip{Ca2(OSO2Me)6(H2O)2}]n (4) incorporating methylviologen or tetra-N-methylpiperazinium (Me4-pip) as a charge-balancing cation. X-ray crystallographic studies of 1–3 emphasize the role of isolated ion-pairs for the construction of hydrogen-bonded supramolecular assemblies and the ability of methanesulfonates to donate electrons (centroid⋯O = 3.09–3.15 Å) to promote photoinduced one-electron reduction of MV2+ to an MV˙+ radical cation in the solid state. The inorganic framework in 4 adopts a layered motif with an inter-lamellar spacing of 11.8 Å, providing spatial expanse to accommodate the organic cations. [ABSTRACT FROM AUTHOR]

A novel dimeric structure based on trilacunary Keggin-type [SbW9O33]9− was synthesized and comprehensively characterized. Different from the conventional dimeric structures, the compound (NH4)10[(SbW9O33)2(UO2)2(H2O)2(SbOH)2]·7H2O ({U2Sb4}) features two additional Sb3+ cations. The successful synthesis of {U2Sb4} reveals the significant role of heteroatoms in structural modulation. The dimer forms a hydrogen-bonded network with water molecules and NH4+ and is therefore expected to exhibit remarkable proton conductivity. Proton conduction studies revealed that {U2Sb4} was a temperature and humidity-dependent proton conductor with conductivity reaching up to 2.50 × 10−2 S cm−1 at 85 °C and 85% RH. [ABSTRACT FROM AUTHOR]

Electrochromic systems capable of switching absorption in the near‐infrared (NIR) region (750–2500 nm) are attractive from the viewpoint of applications for material and life science, and thus several examples have been reported to date. In general, the development of organic‐based systems is needed to reduce the environmental impact and improve biocompatibility. Although extending the switchable spectral range is crucial for the application of organic electrochromic molecules, the switching of NIR absorption based on redox interconversion is still a challenging issue regarding reversibility and durability during interconversion. To overcome this potential instability, the introduction of heteroatoms into the molecular backbone and/or π‐extension could be useful strategies in terms of effective delocalization of charge and spin in the corresponding redox states. In this review, we focus on redox‐active well‐defined small molecules that enable ON/OFF switching of NIR absorption based on precise control of the redox states, and present recent studies on their intrinsic electrochemical and spectroscopic properties and/or structural characterization of their charged states. [ABSTRACT FROM AUTHOR]

Hydride abstraction from the borane adduct, (BICAAC) ⋅ BH3 afforded the hydride bridged dinuclear borenium ion equivalent complexes 1 and 2 that have been characterized by various spectroscopic and spectrometric techniques followed by the assessment of Lewis acidity using the Gutmann‐Beckett method. The single crystal X‐ray structure of complex 2 revealed the presence of discrete ions in the solid state. The complex (BICAAC) ⋅ BH2(OTf) (3), obtained from the reaction of (BICAAC) ⋅ BH3 with MeOTf, formed the corresponding boronium cations [(BICAAC) ⋅ BH2(L)]+(OTf)− on reaction with Lewis bases (L= pyridine (4) and DMAP (5)). Complexes 1 and 2 demonstrated notable catalytic activity in the hydrosilylation of a diverse array of carbonyls using 1.0 mol % catalyst loading (achieving the highest turnover frequency (TOFmax) of up to 1200 h−1 with benzaldehyde. A broad substrate scope has been presented for aldehydes and ketones decorated with various electron‐donating and withdrawing substituents along with this the hydrosilylation of a few para‐quinone methides has also been presented. [ABSTRACT FROM AUTHOR]

A highly selective fluorescent "turn on" probe for Al3+ based on the conjugate of aminourea and pyrazolone was devised and synthesized. The fluorescence intensity of the probe solution was significantly enhanced by the addition of Al3+ to the probe solution. Other cations such as Cu2+, Ni2+, Fe3+, Co2+, Ag+, Mn2+, Sn2+, Sn4+, Mg2+, Li+, Zn2+, Zr4+, Ce3+, Ca2+, and Na+ did not interfere the detection of Al3+. The 1 : 1 complexation between Al3+ and the probe was confirmed by Job's plot curve. In addition, the solution of the complex formed by Al3+ and the probe can be used for the specific detection of Hg2+, appearing as fluorescence quenching. [ABSTRACT FROM AUTHOR]

Taking Nyingchi City as an example, this study explored the distribution of negative air ions (NAIs) in urban green spaces of plateau. Six representative areas of different types of urban green spaces in the main urban area of Nyingchi City were selected for NAIs observation and measurement. The results demonstrated that the NAI concentration in summer was significantly higher than the other three seasons in the study area. The NAI concentration in Fujian Park was significantly higher than the other observation sites, in the order of Fujian Park > the green space of Guangfu Avenue > Wetland Park of Happiness Community > the ecological scenic area of Biri Holy Mountain > Gala Peach Blossom Village > the scenic area of Cypress King's Garden. Pearson's correlation analysis showed that the NAI concentration was positively correlated with positive air ions and humidity, while humidity was positively correlated with NAIs and positive air ions, but negatively correlated with temperature and CO2 concentration (p < 0.05). The correlations between the other variables all have p > 0.05, indicating no statistically significant correlations among them. PCA analysis showed that the highest loading was positive ions with a value of 0.929, and the loading of humidity was −0.876, positively and negatively correlated, respectively. [ABSTRACT FROM AUTHOR]

Chiral hybrid organic–inorganic perovskites (HOIPs) have garnered considerable research interest in the field of optoelectronics, owing to their ability to integrate outstanding optoelectronic characteristics with distinct chiral or spin‐related properties. Although recent years have witnessed the rapid development of chiral perovskites, methods for producing perovskites with high absorption dissymmetry factors (gCD) enabling polarization‐resolved chiroptical applications are still lacking. This study introduces a strategic combination of dual spacer cations, i.e., achiral hexane‐1,6‐diammonium (HDA) and chiral 1‐(chlorophenyl)ethylammonium (ClPEA), for boosting the chiroptical performance of 2D lead iodide HOIPs. Interestingly, ortho‐ClPEA, incapable of forming 2D HOIPs independently, successfully creates 2D structures in collaboration with HDA, exhibiting CD signals aligned with the absorption characteristics of 2D HOIPs. This significant milestone leads to an outstanding gCD value of 0.018, positioning it among the top performers in the field of lead‐based HOIPs. Furthermore, this study demonstrates the fabrication of circularly polarized light (CPL) detectors with a photocurrent dissymmetry factor (gIph) of 0.12, utilizing the HOIPs with enhanced chiroptical activity. [ABSTRACT FROM AUTHOR]

Perovskite solar modules (PSMs) show outstanding power conversion efficiencies (PCEs), but long-term operational stability remains problematic. We show that incorporating N, N-dimethylmethyleneiminium chloride into the perovskite precursor solution formed dimethylammonium cation and that previously unobserved methyl tetrahydrotriazinium ([MTTZ]+) cation effectively improved perovskite film. The in situ formation of [MTTZ]+ cation increased the formation energy of iodine vacancies and enhanced the migration energy barrier of iodide and cesium ions, which suppressed nonradiative recombination, thermal decomposition, and phase segregation processes. The optimized PSMs achieved a record (certified) PCE of 23.2% with an aperture area of 27.2 cm2, with a stabilized PCE of 23.0%. The encapsulated PSM retained 87.0% of its initial PCE after ~1900 hours of maximum power point tracking at 85°C and 85% relative humidity under 1.0-sun illumination. [ABSTRACT FROM AUTHOR]

Background Glycated hemoglobin, or hemoglobin A1c (HbA1c), serves as a crucial marker for diagnosing diabetes and monitoring its progression. We aimed to assess the interference posed by common Hb variants on popular HbA1c measurement systems. Methods A total of 63 variant and nonvariant samples with target values assigned by the International Federation of Clinical Chemistry and Laboratory Medicine (IFCC)-calibrated methods were included. We assessed 6 methods for measuring HbA1c in the presence of HbS, HbC, HbD, HbE, and fetal hemoglobin (HbF): 2 cation-exchange high-performance liquid chromatography (HPLC) methods (Bio-Rad D-100 and HLC-723 G8), a capillary electrophoresis (CE) method (Sebia Capillarys 3 TERA), an immunoassay (Roche c501), an enzyme assay system (Mindray BS-600M), and a boronate affinity method (Primus Premier Hb9210). Results The HbA1c results for nonvariant samples from the 6 methods were in good agreement with the IFCC-calibrated method results. The Bio-Rad D-100, Capillarys 3, Mindray BS-600M, Premier Hb9210, and Roche c501 showed no interference from HbS, HbC, HbD, and HbE. Clinically significant interference was observed for the HLC-723 G8 standard mode. Elevated HbF levels caused significant negative biases for all 6 methods, which increased with increasing HbF concentration. Conclusion Elevated levels of HbF can severely affect HbA1c measurements by borate affinity, immunoassays, and enzyme assays. [ABSTRACT FROM AUTHOR]