Exchange Of Cl Research Articles

Enhanced leaching control of chromium, antimony, and chlorine utilizing CO2-curing slag-fly ash-based agent

This study strives to address the technical bottleneck posed by leaching risks associated with Cr, Sb, and soluble Cl in low-carbon slag-fly ash-based cementitious materials (BFCM) according to our previous research. The introduction of CO2 activation significantly enhances the dissociation of BFS, leading to superior mechanical performance and environmental safety of BFCM. LT3 matrix of BFCM (BFS: MSWI fly ash: FGDG: cement= 42: 20: 10: 28) showed excellent compressive strength (46.79Mpa at 7d). The LT3 matrix enables effective solidification/stabilization (S/S) of Cr, Sb, and Cl with CO2-curing (7d). Furthermore, the leaching concentrations of Sb and Cl within LT system, exhibit a positive correlation, while they demonstrate a negative correlation with Cr. Sb primarily relies on the levels of Ca2+ and OH- in the leaching solution, critical for the formation and stability of Ca-Sb precipitation based Visual MINTEQ fitting. CO2-curing enhances the S/S efficiency of Cl by accelerating the ion exchange of Cl- with OH- in C-A-H and SO42- in the AFm phase, leading to the formation of functional Friedel’s salt. This process is characterized by OH- dissolution and subsequent CaSO4 crystallization. The LT system activated by CO2 exhibited accelerated reaction kinetics relative to traditional hydration (LH), characterized by rapid BFS dissociation and the formation of functional hydration products such as ettringite, C-(A)-S-H, and Friedel's salt. This process also reduced macropores and capillary pores of BFCM, a positive correlation exists between the relative macropore content and Cl leaching levels, whereas the decrease in both macropores and capillary pores is associated with ettringite crystallization.

Primary biliary cholangitis: primary autoimmune disease or primary secretory defect

ABSTRACT Introduction Primary biliary cholangitis (PBC) is a chronic cholestatic liver disease characterized by the immune-mediated destruction of small and medium intrahepatic bile ducts, involving predominantly females. PBC has long been described as an autoimmune liver disease, also because it is very often associated with many autoimmune conditions. More recently, another pathogenic mechanism exploring the damage of cholangiocytes has been hypothesized, i.e. a defect in the biliary umbrella which is physiologically responsible for the exchange of the ions Cl− and HCO3 − and maintains the integrity of glycocalyx. To provide a state-of-the-art analysis of this topic, a systematic review of literature in PubMed, Scopus, and Science Direct was conducted (inclusive dates: 1986–2023). Area covered Although the etiology remains unknown, pathogenesis consists of a complex immune-mediated process resulting from a genetic susceptibility. PBC can be triggered by an immune-mediated response to an autoantigen, which leads to a progressive destruction of bile ducts and eventually to a progressive fibrosis with cirrhosis. The defect in the ‘bicarbonate umbrella’ acts as a protection against the toxic hydrophobic bile acids, leading to a toxic composition of bile. Expert opinion This review offers a summary of the current knowledge about the pathogenesis of PBC, indicating that this is probably based on the mutual relationship between the immune insult and the unbalanced secretory mechanisms.

Phosphorus fluoride exchange: Multidimensional catalytic click chemistry from phosphorus connective hubs

Phosphorus Fluoride Exchange (PFEx) represents a cutting-edge advancement in catalytic click-reaction technology. Drawing inspiration from Nature's phosphate connectors, PFEx facilitates the reliable coupling of P(V)-F loaded hubs with aryl alcohols, alkyl alcohols, and amines to produce stable, multidimensional P(V)-O and P(V)-N linked products. The rate of P-F exchange is significantly enhanced by Lewis amine base catalysis, such as 1,5,7-triazabicyclo[4.4.0]dec-5-ene (TBD). PFEx substrates containing multiple P-F bonds are capable of selective, serial exchange reactions via judicious catalyst selection. In fewer than four synthetic steps, controlled projections can be deliberately incorporated along three of the four tetrahedral axes departing from the P(V) central hub, thus taking full advantage of the potential for generating three-dimensional diversity. Furthermore, late-stage functionalization of drugs and drug fragments can be achieved with the polyvalent PFEx hub, hexafluorocyclotriphosphazene (HFP), as has been demonstrated in prior research.

Zr4+ and glutaraldehyde cross-linked polyethyleneimine functionalized chitosan composite: Synthesis, characterization, Cr(VI) adsorption performance, mechanism and regeneration

In order to improve the stability, electrostatic interaction and ion exchange ability of chitosan for Cr (VI) removal, it is an effective strategy to introduce polyvalent metal ions and polymers into chitosan molecular chain through crosslinking. In this paper, Zr4+ and glutaraldehyde crosslinked polyethyleneimine functionalized chitosan (CGPZ) composite was successfully synthesized and characterized by XRD, SEM, FTIR, BET, and XPS. The results showed that polyethyleneimine was successfully grafted onto chitosan by Schiff base reaction, while the appearance of ZrO and ZrN bonds verified the successful preparation of CGPZ. The monolayer maximum adsorption capacity of Cr(VI) by CGPZ was 593.72 mg g−1 at 298 K and t = 210 min. The removal efficiency of 100 mg L−1 Cr(VI) reached 95.7 %. The thermodynamic, isotherm and kinetic results show that the adsorption process of Cr (VI) by CGPZ is a spontaneous endothermic process controlled by entropy, which accords with Freundlich model and pseudo-second-order kinetic model. The regeneration experiments show that both HCl and NaOH can effectively desorb Cr(III) and Cr(VI) from the adsorbent surface, and the adsorbent has good acid-base resistance and regeneration performance. The removal of Cr(VI) mainly involves electrostatic attraction, ion exchange, reduction and complexation. CGPZ can synergistically adsorb Cr(VI) by electrostatic interaction of -NH2/-C=N and ion exchange of Cl− ion in the center of Zr, then reduce Cr(VI) to Cr(III) (45.4 % at pH = 2.0) by the -OH group on its surface, and chelate Cr(III) through COO- and -NH- groups.

LDH conversion films for active protection of AZ31 Mg alloy

• Zn−Al and Li−Al LDHs with Li-, Mo- and W-based corrosion inhibitors were prepared. • Zn−Al LDH W and Li−Al LDH Li showed the highest corrosion resistance. • XRD, FTIR and XPS analysis confirmed the incorporation of inhibitors. • Active corrosion properties were confirmed by SVET analysis for the Zn−Al LDH W layer. • An inhibition corrosion mechanism is proposed based on several phenomena. Zinc aluminium (Zn-Al) and lithium aluminium (Li-Al) – layered double hydroxides (LDH) coatings with incorporated inhibitors (Li−, Mo− and W−based) were successfully synthesized on AZ31 Mg alloy. Zn−Al LDH W and Li−Al LDH Li showed the highest corrosion resistance and were selected for further evaluation. SEM cross−section examination revealed a bi−layer structure composed of an outer part with loose flakes and a denser inner layer. XRD, FTIR, and XPS analysis confirmed the incorporation of the inhibitors. Post−treatments with corrosion inhibitors containing solutions resulted in the selective dissolution of the most external layer of the LDH coating, reducing the surface roughness, hydrophilicity and paint adhesion of the layers. Active corrosion properties were confirmed by SVET evaluation for the Zn−Al LDH W coating. The proposed active corrosion mechanism involves the ion−exchange of aggressive Cl − ions, deposition of hydroxides and competitive adsorption of W−rich corrosion inhibitors.

Frist principle study of double perovskites Cs2AgSbX6 (X = Cl, Br, I) for solar cell and renewable energy applications

The double perovskites are potential aspirant for clean energy harvesting purposes to cover up the globally shortcomings of energy. Here in the present article, the optoelectronic and thermoelectric characteristics of Cs2AgSbX6 (X = Cl, Br, I) are thoroughly investigated. The dynamic and structural behaviors are determined by tolerance factor, octahedral factor, formation energy and phonon dispersion band structures. It is found the band gaps decreases from 1.94 eV to 1.70 eV, and 0.70 eV by the exchange of Cl with Br and I, respectively. The responsible of reducing band gaps is the p-d hybridization among Ag, Sb, and halogen ions. The first and second absorption peaks are recorded at (344 nm, 400 nm, 620 nm) and (282 nm, 335 nm, 460 nm) for Cs2AgSbCl6, Cs2AgSbBr6 and Cs2AgSbI6, respectively. Therefore, absorption bands shift from ultraviolet to visible and infrared regions. Besides, transport characteristics are evaluated by Boltzmann transport theory. The large Seebeck coefficient, electrical conductivity, and ultralow thermal conductivity enrich the figure of merit at room temperature. Therefore, the studied materials are highly recommended for energy harvesting applications.

Cuprous species distribution over CuCl/NaY dependent on acidity and their CO Adsorption/desorption performance study

• NaY zeolite was synthesized and its acidity was adjusted through NH 4 Cl exchange methods. • Three NaY-Cu samples with identical Cu loading presented different Cu + /Cu 2+ distribution dependent on their acidity. • NaY-Cu presented superior CO storage compared with NaY supports for strong Cu + CO bond. • Cu + cations located in site III and V dominated the CO adsorption compared to site I, II and IV. The impact of acidity on copper species distribution during solid exchange process of CuCl/NaY mixture and their CO storage performance were evaluated in this work. Firstly, the acidity of home-made Na form faujasite (NaY-10) was adjusted through ammonium ion exchange method to obtain its H from supports with different acidity. The bulk characterization results demonstrated the NaY-Cu structure collapsed in varying degrees during solid exchange process, but NaY-Cu samples exhibited superior CO storage ability compared with the corresponding NaY supports. DRIFTs of CO adsorption and simulation through first-principles calculations were further examined to reveal the CO adsorption sites and CO adsorption behaviors over hydroxyls, Na + cations and Cu + /Cu 2+ cations. Finally, the relation between faujasite acidity and CuCl distribution was systematically concluded and the CO adsorption/desorption difference between NaY supports and NaY-Cu samples was directly summarized to illustrate their industrial application potential.

Phosphate sequestration by lanthanum-layered rare earth hydroxides through multiple mechanisms while avoiding the attenuation effect from sediment particles in lake water

Lanthanum-based adsorbents have been used extensively to capture phosphate from wastewater. However, the attenuation effect that arises from the coexistence of sediment and humic acid is the major drawback in practical applications. The Lanthanum-layered rare earth hydroxides (LRHs)-Cl (La-LRH-Cl) was synthesized and achieved high elemental phosphorus (P) adsorption capacity (138.9 mg-P g−1) along with a fast adsorption rate (k2 = 0.0031 g mg−1·min−1) over a wide pH range while avoiding the attenuation effect that arises from the coexistence of sediment and humic acid in lake water. The La-LRH-Cl effectively captured phosphate through multiple interactions, such as the ion exchange of Cl− and phosphate, the memory effect of LRH and the inner-sphere complexation of La-P. Moreover, physical models demonstrated that the adsorption of phosphate onto La-LRH-Cl was a monolayer endothermic process, during which PO43− interacted by multi-docking via parallel orientation at 293 K and multi-ionic interactions through pure non-parallel orientation at 303 K. Hence, 1000 L of 11.08 mg-P L−1 of the acquired lake water was decontaminated by 30 g of La-LRH-Cl to 0.09 mg-P L−1 within 7 days. In addition, over ~12,125 BV of an industrial effluent containing 3.26 mg-P L−1 was treated to below USEPA's discharge limit in fixed-bed tests. It was found that the memory effect of LRH was responsible for the stable performance and reusability. Therefore, more focus should be placed on the collective role of La and LRH layered structure as a means of preventing the attenuation effect in the real water matrix.

Zn/Cu complexes constructed through selective in situ Br–Cl exchange: synthesis, structures, properties, and DFT insights into the Cu-catalyzed mechanism

The coordination polymers of Cu(ii) and Zn(ii) have been synthesized. Simultaneously, the selective in situ Br–Cl exchange mechanism, structures, magnetic properties, and the fluorescence lifetimes of complexes 1–2 are discussed in detail.

Functionalization of nanocellulose to quaternized nanocellulose tri-iodide and its evaluation as an antimicrobial agent

The reported research involves formation of quaternized nanocellulose triiodide for use as an agent for controlled release of iodine. Nanocellulose was extracted from bagasse and the extracted cellulose nanofibers (CNFs) were quaternized with 3-chloro-2-hydroxypropyltrimethyl ammonium chloride (CHPTAC) in NaOH/urea solution. This was followed by exchange of Cl− with I3− by reaction with KI/I2. Nanofibers having I3− anions were characterized by SEM, TEM, XRD, XRF and FTIR spectroscopy. The iodine content was estimated to be 33.42% and the fibers showed no leaching of molecular I2 in detectable amounts. The fibers showed a maximum activity of 94.73% and 99.86% against E. coli and S. aureus, respectively. These are capable of sustaining 100% antimicrobial activity over a period of six months. These fibers can thus find potential applications as a disinfectant agent in biomedical and water purification processes.

Water-soluble ionic liquid as a fluorescent probe towards distinct binding and detection of 2,4,6-trinitrotoluene and 2,4,6-trinitrophenol in aqueous medium

Owing to the escalating threat of criminal activities and pollution aroused by 2,4,6-trinitrotoluene (TNT) and 2,4,6-trinitrophenol (TNP), development of a proficient sensor for the detection of these explosives is highly demanded. Herein, a water-soluble ionic liquid-tagged fluorescent probe, 1-ethyl-3-(3-formyl-4-hydroxybenzyl)-1H-benzimidazol-3-ium chloride (EB-IL) has been designed and synthesized for the detection of TNT and TNP in 100% aqueous medium. The EB-IL fluorescent probe displayed strong cyan-blue fluorescence at 500 nm which gets quenched upon the addition of TNT/TNP over other concomitant nitro-compounds. The distinct binding response of EB-IL towards TNT could be due to the formation of hydrogen bonding between the acidic proton of benzimidazolium (C2–H) and nitro group of TNT. Meanwhile, the selective binding of TNP with EB-IL could be due to the exchange of counter Cl− anion of EB-IL with picrate anion. The fluorescence quenching of EB-IL by TNT could be attributed to the resonance energy transfer (RET) and that of TNP is ascribed to the anion-exchange process. The developed sensor is extremely selective and sensitive towards TNT and TNP with high quenching constants of 1.94 × 105 M−1 and 2.32 × 106 M−1 and shows a lower detection limit of 159 nM and 282 nM, respectively.

Mechanochemical disproportionation reaction of sulfur on Bi2O3 to synthesize Bi2O2S for simultaneous removals of Cu2+ and Cl- from waste solution

As to chemical precipitation for heavy metal removals, sulfide formations will give much lower concentrations of remaining heavy metals and the accompanying salts in the solutions than alkaline neutralization due to much smaller constants of solubility products of the precipitates. However, the preparation of sulfide precipitant such as Na2S by reducing the sulfate with carbon at high temperature is very environmentally risky and bad in cost performance. In this regard, a new approach is proposed just by co-grinding sulfur with bismuth oxide (Bi2O3) with an aid of NaOH to induce a disproportionation reaction of sulfur to prepare Bi2O2S, which can precipitate both Cu2+ and Cl- in case of CuCl2 in the solution at the same time. Under the optimized experimental conditions, removal efficiencies of Cu2+ and Cl- as high as 99.83% and 98.17%, respectively have been achieved at one step. Bi2O2S has a layered structure composed of [Bi2O2]2+ and S2- layers by weak electrostatic interaction. Through the exchange of Cl- to S2-, two kinds of precipitates as BiOCl and copper sulfide can be obtained, offering a new concept to remove both cations and anions simultaneously for the treatment of wastewater, besides the environment-friendliness of the synthesis process itself.

Phosphorus-nitrogen compounds: part 53-synthesis, characterization, cytotoxic and antimicrobial activity, DNA interaction and molecular docking studies of new mono- and dispirocyclotriphosphazenes with pendant arm(s).

Mono-/dispirocyclotriphosphazenes with pendant arm(s) are robust, but they are less investigated inorganic ring systems. In this study, a series of mono (3 and 4)- and dispirocyclotriphosphazenes with 4-chloro-benzyl pendant arm(s) (13-16) was obtained from the Cl exchange reactions of hexachlorocyclotriphosphazene with sodium (N-benzyl)aminopropanoxides (1 and 2). When compound (3) reacted with excess pyrrolidine, morpholine, tetra-1,4-dioxa-8-azaspiro[4,5]decane (DASD) and piperidine, the fully substituted monospirocyclotriphosphazenes (7, 9, 10 and 12) occurred. But, the reactions of 4 with excess piperidine and morpholine produced the gem-piperidino (5)- and morpholino (6)-substituted monospirocyclotriphosphazenes, whereas the reactions of 4 with excess pyrrolidine and DASD gave the fully substituted monospirocyclotriphosphazenes (8) and (11). However, it should be indicated that these derivatives were obtained to be used for the investigation of their spectral, stereogenic and biological properties. The structures of 5, 7 and 14 were determined crystallographically. X-ray data of 5 and 14 displayed that both of compounds were chiral in solid state, and their absolute configurations were assigned as R and RR. Additionally, the antimicrobial activities of phosphazenes were investigated. Minimum inhibitory concentrations, minimal bacterial concentrations and minimum fungicidal concentrations of phosphazenes were determined. The interactions of phosphazenes with plasmid DNA were evaluated by agarose gel electrophoresis. The cytotoxic activities of compounds were studied against L929 fibroblast and DLD-1 colon cancer cells. In addition, density functional theory calculations of 5, 7 and 14 were reported, and their molecular docking studies with DNA, E. coli DNA gyrase and topoisomerase IV were presented.

Anion Exchange‐Induced Crystal Engineering via Hot‐Pressing Sublimation Affording Highly Efficient and Stable Perovskite Solar Cells

Crystalline, dense, and uniform perovskite thin films are crucial for achieving high‐power conversion efficiency solar cells. Herein, a universal method of fabricating highly crystalline and large‐grain perovskite films via crystal engineering is demonstrated. Anion exchange of Cl− and I−, and annealing perovskite films, in an ultraconfined and uniform temperature enclosed space with saturated MAI (or FAI) vapor using hot‐pressing sublimation technology are conducted. This process ensures a rapid crystal growth rate due to fast exchange between the gas phase and the crystalline film to reduce vertically oriented grain boundaries. The generation of the commonly observed PbI2 phase is also suppressed due to the chemical equilibrium state during the thermal annealing process. Using this approach, pinhole‐free perovskite films with preferred crystal orientation and micrometer‐scale grains are obtained, leading to a high steady‐state efficiency of 22.15% based on mixed‐cation perovskite composition. In addition, devices based on different perovskite compositions all exhibit enhanced photovoltaic performance based on the crystal engineering method. The device (without encapsulation) has an efficiency loss of about only 4% after 2520 h of aging in ambient conditions and retains 87% of its initial efficiency after 1000 h of continuous 1 Sun light soaking, thus demonstrating considerably improved stability.

H(+)/Cl(‑) exchange transporter 7 promotes lysosomal acidification‑mediated autophagy in mouse cardiomyocytes.

Autophagy protects cardiomyocytes in various pathological and physiological conditions; however, the molecular mechanisms underlying its influence and the promotion of autophagic clearance are not completely understood. The present study aimed to explore the role of H(+)/Cl(−) exchange transporter 7 (CLC-7) in cardiomyocyte autophagy. In this study, rapamycin was used to induce autophagy in mouse cardiomyocytes, and the changes in CLC-7 were investigated. The expression levels of CLC-7 and autophagy-related proteins, such as microtubule associated protein 1 light chain 3, autophagy related 5 and Beclin 1, were detected using western blotting or immunofluorescence. Autolysosomes were observed and analyzed using transmission electron microscopy and immunofluorescence following CLC-7 silencing with small interfering RNAs. Cellular viability was assessed using Cell Counting Kit-8 and lactate dehydrogenase assays. Lysosomal acidification was measured using an acidification indicator. Increased CLC-7 co-localization with lysosomes was identified during autophagy. CLC-7 knockdown weakened the acidification of lysosomes, which are the terminal compartments of autophagy flux, and consequently impaired autophagy flux, ultimately resulting in cell injury. Collectively, the present study demonstrated that in cardiomyocytes, CLC-7 may contribute to autophagy via regulation of lysosomal acidification. These findings provide novel insights into the role of CLC-7 in autophagy and cytoprotection.

Effect of Sodium Benzenesulfonate on SO42− Removal from Water by Polypyrrole‐Modified Activated Carbon

Sodium benzenesulfonate was doped into polypyrrole‐modified granular activated carbon (pyrrole‐FeCl3·(6H2O)‐sodium benzenesulfonate‐granular activated carbon; PFB‐GAC) with the goal of improving the modified GAC’s ability to adsorb sulfate from aqueous solutions. At a GAC dosage of 2.5 g and a pyrrole concentration of 1 mol L−1, the adsorption capacity of PFB‐GAC prepared using a pyrrole:FeCl3·(6H2O):sodium benzenesulfonate ratio of 1000 : 1500 : 1 reached 23.05 mg g−1, which was eight times higher than that for GAC and two times higher than that for polypyrrole‐modified GAC without sodium benzenesulfonate. Adsorption was favored under acidic conditions and high initial sulfate concentrations. Doping with sodium benzenesulfonate facilitated polymerization to give polypyrrole. Sodium benzenesulfonate introduced more imino groups to the polypyrrole coating, and the N+ sites improved ion exchange of Cl− and SO42− and increased the adsorption capacity of sulfate. Adsorption to the PFB‐GAC followed pseudo‐second‐order kinetics. The adsorption isotherm conformed to the Langmuir model, and adsorption was exothermic. Regeneration using a weak alkali (NH3·H2O), which released OH− slowly, caused less damage to the polypyrrole than using a strong alkali (NaOH) as the regeneration reagent. NH3·H2O at a concentration of 12 mol L−1 (with the same OH− concentration as 2 mol L−1 NaOH) released 85% of the sorbed sulfate in the first adsorption‐desorption cycle, and the adsorption capacity remained >6 mg g−1after five adsorption‐desorption cycles.

Synthesis and Characterization of Ionic Graft Copolymers: Introduction and In Vitro Release of Antibacterial Drug by Anion Exchange.

Amphiphilic graft copolymers based on [2-(methacryloyloxy)ethyl]trimethyl- ammonium chloride (TMAMA) were obtained for the delivery of pharmaceutical ionic drugs, such as p-aminosalicylate (PAS) and clavunate (CLV) anions. The side chains were attached by grafting from a multifunctional macroinitiator via atom transfer radical polymerization (ATRP) to get polymers with different grafting degrees and ionic content. The self-assembling ability, confirmed by determining the critical micelle concentration (CMC) through interfacial tension (IFT) with the use of goniometry, was reduced after ion exchange (CMC twice higher than for chloride anions contained copolymers 0.005–0.026 mg/mL). Similarly, the hydrophilicity level (adjusted by the content of ionic fraction) evaluated by the water contact angle (WCA) of the polymer film surfaces was decreased with the increase of trimethylammonium units (68°–44°) and after introduction of pharmaceutical anions. The exchange of Cl− onto PAS− and CLV− in the polymer matrix was yielded at 31%–64% and 79%–100%, respectively. The exchange onto phosphate anions to release the drug was carried out (PAS: 20%–42%, 3.1–8.8 μg/mL; CLV: 25%–73%, 11–31 μg/mL from 1 mg of drug conjugates). Because of the bacteriostatic activity of PAS and the support of the action of the antibiotics by CLV, the designed water-soluble systems could be alternatives for the treatment of bacterial infections, including pneumonia and tuberculosis.

Decoding the oxygen fugacity of ore-forming fluids from garnet chemistry, the Longgen skarn Pb-Zn deposit, Tibet

The relationship between the compositional zonation of garnet in skarn deposits and the evolution of physicochemical conditions of ore-forming fluids is not clear and needs further investigation. This study presents the characteristics of trace elements of garnet from the Longgen skarn Pb-Zn deposit, Tibet with an aim to reveal the evolution trend of the physical and chemical conditions (fO2 and pH) of ore-forming fluids and to explore the fingerprint of garnet trace elements in different types of skarn deposits.Based on robust alteration halo, mineral assemblages and petrographic observation, the garnets of the Longgen skarn Pb-Zn deposit are divided into two types: (1) distal exoskarn garnet near limestone with ore-bearing and fine oscillatory zoning (Adr39.9-75.0; Grt1, Adr represents andradite) and (2) proximal exoskarn garnet (core: Adr32.9-70.7; rim: Adr83.3-99.5) with Pb-Zn-rich mineral and coarse oscillatory zoning (Grt2). According to the total rare earth element (ΣREE) content in the garnet compositional zone, Grt1 is further divided into three component zones: Grt1-1 (heavy rare earth element (HREE)-enriched chondrite-normalized REE distribution patterns and positive Eu-anomaly (δEu > 1, δEu = 2*(Eusample/Euchondrite)/(Smsample/Smchondrite + Gdsample/Gdchondrite)), Grt1-2 (HREE-enriched REE patterns with negative Eu-anomaly (δEu < 1)), and Grt1-3 (light rare earth element (LREE)-enriched REE patterns with δEu > 1). Similarly, five component zones were identified in Grt2: Grt2-1 (REE-rich REE patterns with δEu < 1), Grt2-2 (LREE-depleted REE patterns with δEu < 1), Grt2-3 (steady REE patterns with δEu < 1), Grt2-4 (LREE-enriched REE patterns with δEu > 1), and Grt2-5 (LREE-enriched REE patterns with δEu < 1) from the core to rim, respectively.The fractionation of LREE with HREE and the behavior of Eu indicate that the physical–chemical conditions during the formation of Grt1-1-Grt1-2 and Grt2-1-Grt2-3 were near neutral (pH = 6–7), and changed to mildly acidic in Grt1-3 and Grt2-4-Grt2-5 (pH < 6–7). In addition, the characteristics of low U (<1 ppm) and the linear relationship between Sn and Eu indicate that the fO2 of the ore-forming fluid was relatively oxidized in comparison to the garnets found in other skarn deposits, and Grt1-1-Grt1-3 and Grt2-1-Grt2-5 have a gradual increasing oxidative ability. The linear relationship between ΣREE and Y/Ca indicates that Grt1 and Grt2 grew in a near-closed system. The incorporation of REE3+ into the garnet was mainly controlled by a “yttrogarnet” (YAG)-type substitution, Ca site vacancy, fluid chemistry, and physicochemical conditions of precipitation. However, the compositional zone at the transition zone between Al-rich and Fe-rich segments in Grt2-4 may be formed in an open system, as suggested by the exchange of LREE and Cl−. In conclusion, garnet crystal growth was affected by the crystal chemistry and physicochemical conditions of the skarn deposit. This study demonstrates that factor analysis and discrimination diagrams (log Sn vs. log U, log Ce vs. log U, and log (Ce + Hf) vs. log U) are effective methods for distinguishing different types of skarn deposits by their contents of redox-sensitive trace elements in garnet.

The order of addition and time matters: Impact of electrolyte processing on micelle-assisted electrosynthesis of mesoporous alloys

Mesoporous thin films are currently awaking a considerable interest for their prospective use in applications ranging from catalysis to energy storage. Yet, some of the synthetic parameters enabling a reproducible development of mesoporosity remain uncontrolled. In this research, we demonstrate that a subtle change in the procedure for the electrolyte preparation for the electrosynthesis of mesoporous Co‒Pt films is critical for reproducing the mesoporosity of the alloys. Specifically, we show that dissolution of the platinum salt (Na2PtCl6·6H2O) in water and storage of the solution (referred to as ‘equilibration time’) before adding the remaining reagents and additives (CoCl2 and P-123) are imperative to consistently reproduce the films mesoporosity. Highly mesoporous Pt-rich Co‒Pt films (10–23 at.% Co), with a pore diameter of 10‒17 nm, were obtained from an electrolyte that involved an equilibration time, while mesoporosity was often absent in films grown from a freshly prepared electrolyte (i.e., upon dissolving all chemicals immediately before electrodeposition). The results suggest that pore formation is governed by the complexation dynamics of Pt(IV) in water, which was investigated by UV–vis spectroscopy. Namely, the concentration of hydroxochloroplatinate complexes ([PtCl6-x(OH)x]2–) originating from the exchange of Cl– by OH– ions increase during the equilibration time. [PtCl6-x(OH)x]2– species would interact more favorably with the hydrophilic poly(ethylene oxide) moieities of P-123 micelles than [PtCl6]2–. The distinct interaction between micelles and the complexes of platinum is key for the reproducible generation of a mesoporous network. Our finding highlights the relevant role of electrolyte processing for the control of mesoporosity in metallic systems prepared by micelle-assisted electrodeposition, which we believe can be extended to many electrolytic processes.

Mono- and dispirocyclotriphosphazenes containing 4-bromobenzyl pendant arm(s): Synthesis, spectroscopy, crystallography and biological activity studies

The N/N donor-type bromobenzyldiamines (1–3) were successively prepared by reduction of Schiff bases formed as a result of condensation reactions of 4-bromobenzaldehyde with aliphatic diamines. The Cl exchange reactions of hexachlorocyclotriphosphazene (HCCP; trimer; N3P3Cl6; 4) with the bidentate ligands (1–3) produced the new monospiro- (5–7) and dispirocyclotriphosphazenes (8–13) containing 4-bromo-benzyl pendant arm(s). The tetrachloro phosphazenes (5–7) were reacted with pyrrolidine, tetra-1,4-dioxa-8-azaspiro [4.5]decane (DASD) and piperidine to give the tetraamino substituted monospirophosphazenes (5a-7c). The spectral analyses of all the phosphazenes were made using appropriate spectroscopic methods; such as FTIR, 1H, 13C, 31P NMR and ESI-MS. The molecular and crystal structures of 5, 6, 7 and 12 were also determined by X-ray crystallography. On the other hand, the antimicrobial activities of the phosphazenes were evaluated against G (−) and G (+) bacteria and fungi. Some of the tetraaminophosphazenes were found to be very active against several bacteria and fungi. Besides, the interactions of the cyclotriphosphazenes with plasmid DNA were investigated using agarose gel electrophoresis.