LaCl3 Research Articles

Acidic Stress Induces Cytosolic Free Calcium Oscillation, and an Appropriate Low pH Helps Maintain the Circadian Clock in Arabidopsis

Acidic stress is a formidable environmental factor that exerts adverse effects on plant growth and development, ultimately leading to a potential reduction in agricultural productivity. A low pH triggers Ca2+ influx across the plasma membrane (PM), eliciting distinct responses under various acidic pH levels. However, the underlying mechanisms by which Arabidopsis plant cells generate stimulus-specific Ca2+ signals in response to acidic stress remain largely unexplored. The experimentally induced stimulus may elicit spikes in cytosolic free Ca2+ concentration ([Ca2+]i) spikes or complex [Ca2+]i oscillations that persist for 20 min over a long-term of 24 h or even several days within the plant cytosol and chloroplast. This study investigated the increase in [Ca2+]i under a gradient of low pH stress ranging from pH 3.0 to 6.0. Notably, the peak of [Ca2+]i elevation was lower at pH 4.0 than at pH 3.0 during the initial 8 h, while other pH levels did not significantly increase [Ca2+]i compared to low acidic stress conditions. Lanthanum chloride (LaCl3) can effectively suppress the influx of [Ca2+]i from the apoplastic to the cytoplasm in plants under acid stress, with no discernible difference in intracellular calcium levels observed in Arabidopsis. Following 8 h of acid treatment in the darkness, the intracellular baseline Ca2+ levels in Arabidopsis were significantly elevated when exposed to low pH stress. A moderately low pH, specifically 4.0, may function as a spatial-temporal input into the circadian clock system. These findings suggest that acid stimulation can exert a continuous influence on intracellular calcium levels, as well as plant growth and development.

Crosstalk of methylglyoxal and calcium signaling in maize (Zea mays L.) thermotolerance through methylglyoxal-scavenging system

Methylglyoxal (MG) and calcium ion (Ca2+) can increase multiple-stress tolerance including plant thermotolerance. However, whether crosstalk of MG and Ca2+ exists in the formation of maize thermotolerance and underlying mechanism still remain elusive. In this paper, maize seedlings were irrigated with MG and calcium chloride alone or in combination, and then exposed to heat stress (HS). The results manifested that, compared with the survival percentage (SP, 45.3%) of the control seedlings, the SP of MG and Ca2+ alone or in combination was increased to 72.4%, 74.2%, and 83.4% under HS conditions, indicating that Ca2+ and MG alone or in combination could upraise seedling thermotolerance. Also, the MG-upraised SP was separately weakened to 42.2%, 40.3%, 52.1%, and 39.4% by Ca2+ chelator (ethylene glycol tetraacetic acid, EGTA), plasma membrane Ca2+ channel blocker (lanthanum chloride, LaCl3), intracellular Ca2+ channel blocker (neomycin, NEC), and calmodulin (CaM) antagonist (trifluoperazine, TFP). However, significant effect of MG scavengers N-acetylcysteine (NAC) and aminoguanidine (AG) on Ca2+-induced thermotolerance was not observed. Similarly, an endogenous Ca2+ level in seedlings was increased by exogenous MG under non-HS and HS conditions, while exogenous Ca2+ had no significant effect on endogenous MG. These data implied that Ca2+ signaling, at least partly, mediated MG-upraised thermotolerance in maize seedlings. Moreover, the activity and gene expression of glyoxalase system (glyoxalase I, glyoxalase II, and glyoxalase III) and non-glyoxalase system (MG reductase, aldehyde reductase, aldo-keto reductase, and lactate dehydrogenase) were up-regulated to a certain extent by Ca2+ and MG alone in seedlings under non-HS and HS conditions. The up-regulated MG-scavenging system by MG was enhanced by Ca2+, while impaired by EGTA, LaCl3, NEC, or TFP. These data suggest that the crosstalk of MG and Ca2+ signaling in maize thermotolerance through MG-scavenging system. These findings provided a theoretical basis for breeding climate-resilient maize crop and developing smart agriculture.

Lanthanum chloride exerts therapeutic potential for chronic kidney disease by suppressing nanohydroxyapatite-induced mitophagy and mitochondria-mediated apoptosis

ObjectiveTo investigate the protective effect of lanthanum chloride on kidney injury in chronic kidney disease and its mechanism. Methods1. Patients with CKD stage 2–5 were selected to analyze the effect of lanthanum-containing preparations on CKD. 2. Sixty healthy male Wistar rats were randomly divided into control group, model group, lanthanum chloride groups (0.03 ng/kg, 0.1 ng/kg, 0.3 ng/kg, q.3d., i.v.), and lanthanum carbonate group (0.3 g/kg, q.d., p.o.). The model group was given 2 % adenine suspension (200 mg/kg, q.d., p.o.) for the first two weeks, followed by adenine (200 mg/kg, b.i.d., p.o.) for 2 weeks, and all animals were sacrificed after eight weeks of administration. 3. The serum and kidneys of rats in each group were collected to detect the oxidative stress indicators and the expressions of LC3B-Ⅱ/Ⅰ, p62, Bcl-2, Bax, Caspase-3 and Cleaved Caspase-3. 4. Human renal tubular epithelial cells (HK-2 cells) were divided into control group, model group, lanthanum chloride group, pyrophosphate (PPI) group, chloroquine (CQ) group, rapamycin group, doxorubicin (DOX) group and N-acetyl-L-cysteine (NAC) group. The mitochondrial status, mitophagy and apoptosis levels were detected. Results1.Lanthanum-containing preparations can significantly reduce the biochemical indexes of kidney injury in patients with CKD. 2. In the model group, the glomerular and renal tubular edema, the mitochondria were short and round, and the expression of LC3B-Ⅱ/Ⅰ and Bax increased, while the expression of P62, Bcl-2 and Caspase-3 decreased, and there was a significant improvement in the administration group, especially the 0.1 ng/kg group and lanthanum carbonate group. 3. In the HK-2 cell model group, mitochondrial membrane potential decreased, morphology changed and the results were reversed by lanthanum chloride. ConclusionLanthanum chloride may alter the morphology of nano-hydroxyapatite, thereby inhibiting its induced mitophagy and mitochondria-mediated apoptosis, and ultimately improve CKD renal injury effectively.

Lanthanum hydroxide@cellulose membranes with tunable pore sizes for selective removal of dyes with the same charges

Adsorptive membranes for the efficient separation of dyes with the same charges are quite desirable. Herein, a novel membrane of lanthanum hydroxide/cellulose hydrogel coated filter paper (LC) was prepared through a facile strategy of dip-coating followed by freeze-shaping. With the aid of cellulose gel, the generated La(OH)3 achieved fine dispersion. In addition, the pore size of LC membrane could be regulated by altering the cellulose concentration or the lanthanum chloride dosage, which was crucial for its water flux. In particular, the obtained membrane possessed a high water flux (128.4 L m−2 h−1) and a high dye rejection (97.2 %) for anionic Congo red (CR) only driven by the gravity, which outperformed many previously reported membranes. More intriguingly, its dye rejection for anionic methyl orange (MO) was only 0.9 %, exhibiting high selectivity for dyes with the same charges. Single-solute adsorption experiments indicated that the CR adsorption on the membrane was best fitted by the pseudo-first-order kinetic model, and it followed the Langmuir monolayer adsorption mechanism.

Exogenous Calcium Alleviates the Photosynthetic Inhibition and Oxidative Damage of the Tea Plant under Cold Stress

Calcium (Ca2+), a second messenger, plays a crucial role in plant growth and development as well as in responding to biotic and abiotic stresses. In this work, we explored the role of exogenous calcium in alleviating cold stress and examined the relationship between calcium chloride (CaCl2) and calcium channel blockers, lanthanum chloride (LaCl3), in tea plants under cold stress at the physiological and transcriptional levels. Exogenous Ca2+ partially offsets the negative impacts of cold stress which increased the tolerance of tea plants by significantly raising the photochemical efficiency of PSII, protective enzyme activities, and the ABA content, which reduced the relative electrical conductivity (REC) level and the malondialdehyde (MDA) concentration. At the transcriptome level, exogenous Ca2+ significantly enhanced the expression of key genes involved in cold response pathways. Nevertheless, LaCl3 treatment not only significantly inhibited the activities of antioxidant enzymes including superoxide dismutase (SOD), peroxidase (POD) and catalase (CAT), but also increased cold damage. This study aims to provide essential insight into the role of exogenous Ca2+ in tea plants responding to cold stress, and to better understand the molecular mechanisms that facilitate Ca-mediated cold tolerance.

Enhancing fire performance and thermal stability of flexible PVC with lanthanum phytate montmorillonite

This study presents a breakthrough approach to enhance the thermal stability, mechanical properties, and flame retardancy of flexible PVC (fPVC). It introduces lanthanide phytate montmorillonite (Pa-La-Mt) as an innovative nanofiller. Pa-La-Mt was synthesized by intercalating sodium phytate and lanthanum chloride into the interlayer space of montmorillonite (Mt), effectively increasing the layer spacing. The analysis of this study, using X-ray diffraction (XRD) and Fourier infrared spectrometer (FTIR), confirmed this structural transformation. The influence of Pa-La-Mt on the structural and performance aspects of fPVC composites was thoroughly examined. Scanning electron microscopy (SEM), thermogravimetric analysis (TGA), mechanical testing, limit oxygen index (LOI), and cone calorimeter (CONE) revealed compelling outcomes. Pa-La-Mt not only improved the dispersion and compatibility of Mt. within the fPVC matrix but also enhanced the thermal stability and mechanical performance of fPVC composites. Most notably, Pa-La-Mt exhibited remarkable flame retardant and smoke suppression effects on fPVC composites. It led to a substantial increase in LOI value, a reduction in the peak heat release rate and total heat release amount, and a decrease in CO and CO2 emissions. This underlines Pa-La-Mt as a promising nanofiller with profound implications for various fPVC applications.

Metachrony drives effective mucociliary transport via a calcium-dependent mechanism.

The mucociliary transport apparatus is critical for maintaining lung health via the coordinated movement of cilia to clear mucus and particulates. A metachronal wave propagates across the epithelium when cilia on adjacent multiciliated cells beat slightly out of phase along the proximal-distal axis of the airways in alignment with anatomically directed mucociliary clearance. We hypothesized that metachrony optimizes mucociliary transport (MCT) and that disruptions of calcium signaling would abolish metachrony and decrease MCT. We imaged bronchi from human explants and ferret tracheae using micro-optical coherence tomography (µOCT) to evaluate airway surface liquid depth (ASL), periciliary liquid depth (PCL), cilia beat frequency (CBF), MCT, and metachrony in situ. We developed statistical models that included covariates of MCT. Ferret tracheae were treated with BAPTA-AM (chelator of intracellular Ca2+), lanthanum chloride (nonpermeable Ca2+ channel competitive antagonist), and repaglinide (inhibitor of calaxin) to test calcium dependence of metachrony. We demonstrated that metachrony contributes to mucociliary transport of human and ferret airways. MCT was augmented in regions of metachrony compared with nonmetachronous regions by 48.1%, P = 0.0009 or 47.5%, P < 0.0020 in humans and ferrets, respectively. PCL and metachrony were independent contributors to MCT rate in humans; ASL, CBF, and metachrony contribute to ferret MCT rates. Metachrony can be disrupted by interference with calcium signaling including intracellular, mechanosensitive channels, and calaxin. Our results support that the presence of metachrony augments MCT in a calcium-dependent mechanism.NEW & NOTEWORTHY We developed a novel imaging-based analysis to detect coordination of ciliary motion and optimal coordination, a process called metachrony. We found that metachrony is key to the optimization of ciliary-mediated mucus transport in both ferret and human tracheal tissue. This process appears to be regulated through calcium-dependent mechanisms. This study demonstrates the capacity to measure a key feature of ciliary coordination that may be important in genetic and acquired disorders of ciliary function.

A study on the performance of a recyclable adsorbent La@Fe for phosphate adsorption in wastewater

Phosphorus(P) is the key element of the growth of phytoplankton, and is also significant cause of water eutrophication. In this work, the magnetic Fe3O4 (FE) microspheres were employed as the core material, the La compound was coated on the surface of the FE microspheres and the adsorbent obtained was denoted as La@Fe. The effects of preparation conditions including the dosage of NaOH, the preparation time, the ratio of FE and LaCl3 (LC), and the stirring time were discussed. The optimized La@Fe has a good adsorption capacity (130–160 mg·g−1) and strong magnetic recovery capacity (43.4 emu/g). In the low concentration (1 mg·L−1), the optimized La@Fe still had an excellent performance. It can keep a good adsorption in a wide pH range (3−8). Except Na2CO3, common anions (NaHCO3, NaCl, NaNO3, Na2SO4, KF, KNO2) in the wastewater could not affect the adsorption capacity of La@Fe. After 7 regeneration, the adsorption capacity of La@Fe reduced by 25% indicating the excellent regeneration property of La@Fe. The La@Fe was analyzed by SEM, TEM, XRD, XPS, BET, and LPS, and the obtained results showed that the particles of La@Fe were spherical, the particle sizes were between 0.1 and 100μm. The main components at the surface of La@Fe was La-(OH), which adsorbed phosphate to form La-PO4. The specific surface area of La@Fe was small and the mesopores were main pore structure. In addition, the adsorption kinetics analysis indicated that the Elovich model worked well on modeling La@Fe adsorbing phosphate, so the adsorption was chemical adsorption with heterogeneous adsorbing surfaces. Adsorption isotherms experiments revealed that the increasing adsorption temperature would enhance the adsorption capacity of La@Fe. It could be obtained from the thermodynamic experiments that the adsorption process was endothermic and chemical adsorption. Therefore, La@Fe is an excellent phosphate adsorbent and has a good application prospect in the field of phosphorus recovery and adsorbent reuse.

Improving uniformity and performance of electroformed copper using rare earth element additives

Electroforming can realize high precision and complex shape parts manufacturing, making it widely used in the field of micromachining and micromanufacturing. The drawback lies in the nonuniform thickness distribution, which can cause quality issues including voids, pitting, and particles. In order to enhance the microstructure uniformity and electroforming performance, lanthanum chloride and cerium chloride were employed as additives in the copper electroforming experiment. This study analyzes the effects of lanthanum chloride and cerium chloride on the surface morphology, microhardness, tensile strength, and uniformity of electroformed copper deposits. The results show that adding rare earth elements into the electrolyte solution can improve thickness uniformity, promote ion mass transfer, and refine the copper deposit’s grain. Compared to the microstructure without adding additives, the copper deposit’s nonuniformity prepared with 1.0 g/L lanthanum chloride is 76.9% lower, and with cerium chloride, it is 72% lower. Additionally, the copper deposit prepared with lanthanum chloride exhibits superior overall quality compared to that prepared with cerium chloride.

Screening of salt hydrates and cellulose nanocrystal composites for thermochemical energy storage using life cycle assessment

Salt hydrate systems via thermochemical reactions can provide thermal storage for renewable-sourced alternatives to traditional heating systems like natural gas. In this study, we use life cycle analysis (LCA) along with the material prices to screen salts based on environmental impact and cost. Additionally, we performed LCA of producing a composite material of salt and cellulose nanocrystals (CNC) at a weight ratio of four to one. CNC is a stabilizing agent for salt. We assessed the salt-CNC composites based on a laboratory scale and scaled-up processing to identify low environmental impact formulations and to identify high environmental impact processes in the composite production. In general, lanthanum chloride, lithium hydroxide, and lithium chloride should be avoided due to high environmental impact or cost. For pure salts, our results showed magnesium sulfate, zinc sulfate, and calcium chloride are typically preferred with a close second tier of magnesium and strontium chlorides and strontium bromide. For the composite material, magnesium sulfate was preferred followed by zinc sulfate, sodium sulfide, and strontium chloride. CNC has a significant environmental impact, contributing over 50% of the environmental impact for these composites. Therefore, CNC production with lower environmental impacts needs to be pursued. In composite production, the environmental impact of mixing and sonication can be reduced by scaling production. However, drying remains a high-impact process. These results can help guide salt selection for other salt-based thermochemical materials and further development of the salt-CNC composite.

Preparation of Lanthanum by the Lithium-thermic Method

Purification of unwanted impurities from rare earth products was carried out using inorganic and organic precipitating reagents. A 1 M solution of 8-hydroxycholine was used as organic precipitants. The use of organic precipitants forms stable intracomplex compounds with metal cations. Solutions of barium chloride and ammonia solution were used as inorganic precipitants. For the precipitant, specific and highly volatile precipitant reagents were chosen when heated. Iron, aluminum, sodium and sulfate ions were extracted from the product under study, because the chemical composition of the slag contains more of them. Enriched concentrated lanthanum chloride powder was reduced with lithium to lanthanum metal. Lanthanum is obtained in the form of large crystals with a purity of 99.6% by weight.

Preparation, spectroscopic and anticancer investigations of metal-drug complexes associated between flumequine antibiotic drug with lanthanum(III), samarium(III) and terbium(III) chloride

Flumequine ligand (FLQ) metal complexes of the [M(FLQ)2(Cl)(H2O)].nH2O type, where M are (La(III), Sm(III), and Tb(III)) and FLQ is flumequine have been synthesized. The FLQ metal complexes could be prepared using MCl3 : flumequine in stoichiometry of 1:2 in situ bidentate chelation. The characterization of FLQ complexes obtained have been done using elemental analyses (%C, %H and %N), molar conductivity (Ʌm), infrared spectroscopy (FTIR), electronic spectra (UV-Vis), thermal analysis (TGA), and physicochemical techniques such as X-ray powder diffraction (XRD), scanning electron microscopy (SEM), and energy dispersive X-ray (EDX) measurements at room temperature. Accordingly, these complexes are indicative of an octahedral coordination structure. Flumequine ligand has a bidentate fashion through the oxygen atoms of carbonyl (quinolone) and carboxylic groups. The findings demonstrated the anti-cancer efficacy of these compounds against HepG-2 and MCF-7 cancer cell lines at extremely low doses of up to 58.2 mg/mL. The La(III) complex was shown to have the highest selectivity against cancer cells in comparable with both samarium and terbium(III) complexes.&#x0D; KEY WORDS: Flumequine, Lanthanide metal ions, FTIR, EDX, Complexation, Anticancer activity&#x0D; Bull. Chem. Soc. Ethiop. 2024, 38(3), 671-684. &#x0D; DOI: https://dx.doi.org/10.4314/bcse.v38i3.10

Synthesis, spectroscopic characterization and optical studies of poly(AN-co-St) composites with doped lanthanum (III) chloride for aerospace applications

Synthesis, spectroscopic characterization and optical studies of poly(AN-co-St) composites with doped lanthanum (III) chloride for aerospace applications

A new method for preparation of RE2(CO3)3 by multi-membrane electroconversion

Preparing rare earth carbonates from rare earth chlorides is a common step in the smelting process for all rare earth ores; however, it produces large amounts of ammoniacal nitrogen wastewater and a chloride-rich precipitate. This study proposes a novel, green and simple process for preparing low-chlorine lanthanum carbonate via a multi-membrane electroconversion approach. The effects of the CO2 flow rate, current density, lanthanum chloride concentration, and electroconversion time on the electroconversion process were systematically explored. Under the optimal process conditions (CO2 flow rate = 0.5 L/min, current density = 25 mA/cm2, LaCl3 concentration = 0.3 mol/L, electroconversion time = 60 min), a current efficiency of 75.77% was obtained, along with a unit energy consumption of 5.44 kW h/kg. X-ray diffraction, Fourier transform infrared spectroscopy, thermogravimetric analysis, and laser particle size analysis results indicate that a pure La2(CO3)3·8H2O product is obtained with a median particle size of 6.53 μm and chlorine content of 0.0021%. In addition, scanning electron microscopy and transmission electron microscopy observations indicate that the crystallisation and growth of La2(CO3)3·8H2O conform to the oriented attachment and Ostwald ripening mechanisms. Thus, the proposed multi-membrane electroconversion method provides guidance toward the clean transformation of rare earth chlorides to low-chlorine lanthanum carbonates.

Unraveling the impact of lanthanum on methane consuming microbial communities in rice field soils.

The discovery of the lanthanide requiring enzymes in microbes was a significant scientific discovery that opened a whole new avenue of biotechnological research of this important group of metals. However, the ecological impact of lanthanides on microbial communities utilizing methane (CH4) remains largely unexplored. In this study, a laboratory microcosm model experiment was performed using rice field soils with different pH origins (5.76, 7.2, and 8.36) and different concentrations of La3+ in the form of lanthanum chloride (LaCl3). Results clearly showed that CH4 consumption was inhibited by the addition of La3+ but that the response depended on the soil origin and pH. 16S rRNA gene sequencing revealed the genus Methylobacter, Methylosarcina, and Methylocystis as key players in CH4 consumption under La3+ addition. We suggest that the soil microbiome involved in CH4 consumption can generally tolerate addition of high concentrations of La3+, and adjustments in community composition ensured ecosystem functionality over time. As La3+ concentrations increase, the way that the soil microbiome reacts may not only differ within the same environment but also vary when comparing different environments, underscoring the need for further research into this subject.

Degradation of deoxynivalenol by a mixed bacteria with lanthanum chloride as a growth factor

Food and feed are susceptible to deoxynivalenol (DON) infection during storage. Biodetoxification is a way to reduce the harmful effects of DON and ensure food and feed safety. In this study, lanthanum chloride was used as a growth factor to enrich DON degrading bacteria and the mixed bacteria SH7 was obtained. The DON degrading mechanism of SH7 and its application in corn DON detoxification were explored. Results showed that lanthanum chloride promoted DON degradation of SH7 by affecting its microbial composition, related gene expression level and metabolites. SH7 may have quorum sensing of DON and collectively initiate the expression of DON detoxification genes. SH7 could also utilize a large amount of arginine to resist the toxic effects of DON. In addition, the DON degrading rate of SH7 in corns was 26.95 %. This research provides a theoretical basis for applying the mixed bacteria SH7 in the detoxification of DON in corns.

Synthesis, Growth, and Characterization of Structural, Optical, and Nonlinear Optical Properties of L‐Proline Tartrate Added by Lanthanum Chloride Single Crystal

L‐proline tartrate (LPT), 1 and 2 mol% of lanthanum chloride‐ (LaCl3‐) doped LPT single crystals have been synthesized and grown using a slow evaporation solution method at room temperature. The crystals have undergone different characterization studies to test their suitability for device fabrication. The single crystal X‐ray diffraction studies have revealed that both 1 and 2 mol% of LaCl3‐doped LPT single crystals have been crystalized monoclinic crystal structure and space group P21. The UV‐Vis‐NIR spectrum analysis has shown that pure, 1, and 2 mol% of LaCl3‐doped LPT single crystals have good optical transparency in the entire visible and near IR region. The optical band gap energy for pure, 1 and 2 mol% of LaCl3‐doped LPT single crystals to be 4.9, 5, and 5.1 eV, respectively. The energy dispersive X‐ray analysis confirmed that LaCl3 has been incorporated into LPT crystal. The second harmonic generation (SHG) efficiency for 1 and 2 mol% of LaCl3‐doped LPT single crystals has been tested and found to be 1.27 and 1.6 times greater than that of the reference KDP crystal, respectively.

Calcium signal regulated carbohydrate metabolism in wheat seedlings under salinity stress.

This study aimed to explore the mechanism by which calcium (Ca) signal regulated carbohydrate metabolism and exogenous Ca alleviated salinity toxicity. Wheat seedlings were treated with sodium chloride (NaCl, 150mM) alone or combined with 500μM calcium chloride (CaCl2), lanthanum chloride (LaCl3) and/or ethylene glycol tetraacetic acid (EGTA) to primarily analyse carbohydrate starch and sucrose metabolism, as well as Ca signaling components. Treatment with NaCl, EGTA, or LaCl3 alone retarded wheat-seedling growth and decreased starch content accompanied by weakened ribulose-1,5-bisphosphate carboxylation/oxygenase (Rubisco) and Rubisco activase activities, as well as enhanced glyceraldehyde-3-phosphate dehydrogenase, phosphoglycerate kinase, alpha-amylase, and beta-amylase activities. However, it increased the sucrose level, up-regulated the sucrose phosphate synthase (SPS) and sucrose synthase (SuSy) activities and TaSPS and TaSuSy expression together, but down-regulated the acid invertase (SA-Inv) and alkaline/neutral invertase (A/N-Inv) activities and TaSA-Inv and TaA/N-Inv expression. Except for unchanged A/N-Inv activities and TaA/N-Inv expression, adding CaCl2 effectively blocked the sodium salt-induced changes of these parameters, which was partially eliminated by EGTA or LaCl3 presence. Furthermore, NaCl treatment also significantly inhibited Ca-dependent protein kinases and Ca2+-ATPase activities and their gene expression in wheat leaves, which was effectively relieved by adding CaCl2. Taken together, CaCl2 application effectively alleviated the sodium salt-induced retardation of wheat-seedling growth by enhancing starch anabolism and sucrose catabolism, and intracellular Ca signal regulated the enzyme activities and gene expression of starch and sucrose metabolism in the leaves of sodium salt-stressed wheat seedlings.

Characterization of Water Vapor Sorption Performance and Heat Storage of MIL-101 (Cr) Complex MgCl2, LiCl/LaCl3 System for Adsorptive Thermal Conversion.

Adsorption heat conversion systems can provide heating and cooling across time and space in a more environmentally friendly way. Porous materials are potential candidates for water-based adsorption thermal conversion, in which a metal-organic framework (MOF) has a larger specific surface area and porosity than other porous matrices. However, many MOFs with high saturated adsorption capacity have great deficiencies in performance at low water vapor partial pressure, which hinder their application in adsorption thermal conversion. To improve the water vapor adsorption performance of MIL-101 (Cr), different contents of magnesium chloride, lithium chloride, and lanthanum chloride are mixed into MIL-101 (Cr) by an impregnation method. The properties and structures of the materials are characterized by XRD, SEM, nitrogen adsorption tests, water vapor adsorption tests, TG, FTIR, and so on. The results show that the saturated water vapor adsorption capacity of the sample impregnated with salt increases by 1.5-2.3 times, up to 2.24 g/g, compared with that of the unimpregnated sample. When the partial pressure of water vapor is 0.3, the adsorption capacity increases by 5.3-7.5 times and reaches 0.68 g/g at most. The maximum heat storage density of impregnated samples can be increased by 866 J/g. Impregnated MgCl2 can greatly improve the adsorption and thermal conversion performance of MOF, and impregnated MgCl2 and the proper amount of LiCl can further improve the performance of the material system. Our experiments show that the composite impregnation of magnesium chloride and the proper amount of lithium chloride can improve the application performance of the MOF materials in the adsorption thermal conversion process.

INVESTIGATION OF THE MECHANISM OF LANTHANUM IONS ELECTROREDUCTION ON NICKEL ELECTRODE IN CHLORIDE MELT

The electrochemical behavior of lanthanum ions on a nickel electrode has been studied using various electrochemical methods such as cyclic voltammetry, chronopotentiometry, open circuit chronopotentiometry (on-off curves), and square wave voltammetry in an equimolar melt of potassium and sodium chlorides at 973 K. The cyclic voltammetry curves has several reduction waves on the cathodic branch and corresponding oxidation waves on the anodic branch. The first wave A is located in the potential region –(0.0–0.1) V, where the reduction of Ni2+ ions takes place. The second wave B is in the region of potentials –(1.72–1.77) V, on it occurs electroreduction of ions \({\text{LaCl}}_{6}^{{3 - }}\) on nickel electrode with certain depolarization with formation of intermetallide of lanthanum with nickel LaxNiy. The appearance of the third wave C in the potential region –(2.09–2.13) V, we associate with the electroreduction of chloride complexes \({\text{LaCl}}_{6}^{{3 - }}\) on intermetallide LaxNiy with the formation of metallic lanthanum. On the basis of the obtained data it is shown that during the electroreduction of lanthanum chloride complexes in KCl–NaCl melt at T = 973K the nickel electrode interacts with the released lanthanum, causing a significant depolarization of the process of electroreduction of the chloride complex, also formation of intermetallide with Ni electrode occurs.