Enhancement of corrosion resistance of AZ31 Mg alloys by one-step in situ synthesis of ZnAl-LDH films intercalated with organic anions(ASP, La)

Inserting corrosion inhibitors into a lamellar protective coating is an effective way to improve the corrosion resistance of metal substrates.In this work,two kinds of environmentally friendly organic acid anions,aspartic acid(ASP)and lauric acid(La),were explored as corrosion inhibitors to in situ intercalate into the Zn Al-layered double hydroxides(Zn Al-LDHs)on AZ31 magnesium alloys by a facile one-step hydrothermal method.The morphology,composition,structure and the corrosion resistance of these two LDHs coating before and after corrosion experiment were investigated.It is found that both the two kinds of Zn Al-LDHs films consist of uniform and dense layered nanosheets(NSs),and the NSs of ZnAl-ASP-LDHs films grow vertically,but those of ZnAl-La-LDHs films exhibit a staggered tilted structure.The corrosion current density of the two Zn Al-LDHs films are two orders of magnitude lower than that of Mg alloy substrate.After one week’s immersion in NaCl solution,the NSs structure of two kind of ZnAl-LDHs films still remains the uniform and densely coverage on Mg alloy.Owing to the larger d(003)spacing,the ZnAl-La-LDHs have better ability to absorb Cl-and release interlayer anions than Zn Al-ASP-LDHs.These results indicate that the Zn Al-LDHs films intercalated with organic anions,specially La anions,can significantly improve the corrosion resistance of Mg alloy.

Synthesis of Three-Dimensional Hierarchical Flower-Like Mg–Al Layered Double Hydroxides with Excellent Adsorption Performance for Organic Anionic Dyes

In this work,a facile and effective strategy to prepare three-dimensional(3D)hierarchical flower-like Mg–Al layered double hydroxides(3D-LDH)was developed via a one-step double-drop coprecipitation method usingγ-Al 2O 3particles as a template.The characterization and experimental results showed that the calcined product,3D-LDO,features a large specific surface area of 204.2 m^(2)/g,abundant active sites,and excellent adsorption performance for Congo red(CR),methyl orange(MO),and methyl blue(MB).The maximum adsorption capacities of 3D-LDO for CR,MO,and MB were 1428.6,476.2,and 1666.7 mg/g,respectively;such performance is superior to that of most reported adsorbents.The adsorption mechanism of organic anionic dyes by 3D-LDO was extensively investigated and attributed to surface adsorption,the memory effect of 3D-LDO,and the unique 3D hierarchical flower-like structure of the adsorbent.Recycling performance tests revealed that3D-LDO has satisfactory reusability for the three organic anionic dyes.

Effects of Cangfudaotan Tang on Expression of Organic Anion Transporting Polypeptide (oatp2b1) in Liver and Kidney Tissues of Rats with Phlegm Dampness Type Polycystic Ovary Syndrome (PCOS)

Objective: To explore the effect of Cangfudaotan Tang on phlegm dampness type of PCOS and the role of oatp2b1 in transportation and transformation of phlegm dampness. Methods: 36 SD female rats were randomly divided into three groups: blank control group, model group and Cangfudaotan Tang group, 12 cases in each one. After PCOS rat models were made, rats of Cangfudaotan Tang group were treated with Cangfudaotan Tang (1.42 g/kg/d) by intragastric administration for 14 days;blank control and model group were given with isodose saline. The expression of oatp2b1 mRNA/Protein in liver and kidney tissues was measured and the level of testosterone (T), follicle stimulating hormone(FSH), estradiol (E2), luteinizing hormone(LH), Serum total cholesterol (TG), Triacylglycerols (TC), high density lipoprotein cholesterol (HDL-C) and low density lipoprotein cholesterol (LDL-C) were detected at the same time. Results: Compared with blank control group, the expression of oatp2b1 mRNA and the level of TC, TG, LDL, LH, FSH, T in model group were significantly increased (P < 0. 05), while the level of HDL was significantly decreased (P < 0. 05);compared with model group, the expression of oatp2b1 mRNA and the level of TC, TG, LDL in Cangfudaotan Tang group were significantly lowered (P < 0.05);the level of HDL was significantly higher;the oatp2b1 protein in kidney and liver tissues had different degrees of expression, while there was no statistical significance among the three groups. Conclusions: Oatp2b1 might be one of the material bases participating in transportation and transformation of phlegmy dampness. The mechanism of Cangfudaotan Tang treating phlegm dampness type of PCOS may be achieved by regulating the expression of oatp2b1.

Influence of organic anion transporting potypeptide(SLCO1B1 and SLCO1B3)genetic polymorphisms on mycophenolic acid in Chinese kidney transplantation patients

Objective To analyze the relationship between genetic polymorphisms of organic anion transporting polypeptide ( SLCO1B1 and SLCO1B3) and mycophenolic acid ( MPA) pharmacokinetics in Chinese kidney transplant recipients. Methods Gene mutations ( SLCO1B3 T334G,SLCO1B1 A338G) were detected in 68 recipi-

Deep dive into anionic metal-organic frameworks based quasi-solid-state electrolytes

The development and application of high-capacity energy storage has been crucial to the global transition from fossil fuels to green energy.In this context,metal-organic frameworks(MOFs),with their unique 3D porous structure and tunable chemical functionality,have shown enormous potential as energy storage materials for accommodating or transporting electrochemically active ions.In this perspective,we specifically focus on the current status and prospects of anionic MOF-based quasi-solid-state-electrolytes(anionic MOF-QSSEs)for lithium metal batteries(LMBs).An overview of the definition,design,and properties of anionic MOF-QSSEs is provided,including recent advances in the understanding of their ion transport mechanism.To illustrate the advantages of using anionic MOF-QSSEs as electrolytes for LMBs,a thorough comparison between anionic MOF-QSSEs and other well-studied electrolyte systems is made.With these in-depth understandings,viable techniques for tuning the chemical and topological properties of anionic MOF-QSSEs to increase Li+conductivity are discussed.Beyond modulation of the MOFs matrix,we envisage that solvent and solid-electrolyte interphase design as well as emerging fabrication techniques will aid in the design and practical application of anionic MOF-QSSEs.

Phenylhydrazone anions excitation for the photochemical carbonylation of aryl iodides with aldehydes

Spectroscopic investigations discovered that the in-situ generated phenylhydrazone anion was significantly bathochromically shifted to visible light region for photoactivation under irradiation. The photoexcited phenylhydrazone anion was potential to reduce aryl iodides via single electron transfer process for the subsequent radical chain reaction. A redox-neutral photochemical carbonylation of aryl iodides was developed on basis of the special spectroscopic features of phenylhydrazone anion. This protocol provided a convenient and efficient synthetic tool for accessing carbonylation products under redox neutral conditions without the need of transition-metals.

An Anionic Covalent Organic Framework as an Electrostatic Molecular Rectifier for Stabilizing Mg Metal Electrodes

Despite its potential as a high-capacity battery electrode,magnesium(Mg)metals are highly susceptible to electrolytes,resulting in the formation of unwanted passivation layers,which hinder charge transfer phenomena.Here,we first report an anionic covalent organic framework(a-COF)as an electrostatic molecular rectifier(that can preferentially trap solvent molecules)to stabilize Mg metal electrodes.Compared to a neutral COF(n-COF)as a control sample,the a-COF enhances Mg^(2+)transport by facilitating the desolvation of Mg^(2+)-solvent complexes and cationic mobility through its negatively charged one-dimensional columns,thereby achieving an ionic conductivity eight times higher than that of the n-COF.In addition,the anionic porous frameworks in contact with Mg metal electrodes enable a uniform Mg^(2+)flux and interfacial stability with Mg metal electrodes.Consequently,the a-COF exhibited reversible Mg plating/stripping cyclability on Mg metal electrodes compared to the n-COF,demonstrating the electrochemical viability of the anionic frameworks for Mg metal electrode stabilization.

Total Saponins from Dioscorea Septemloba Thunb Reduce Serum Uric Acid Levels in Rats with Hyperuricemia through OATP1A1 Up-regulation

The aim of this study is to evaluate the efficacy of total saponins of Dioscorea（TSD）, an extract of the Chinese herbal Bi Xie, on hyperuricemia and to elucidate the underlying mechanisms. The rat hyperuricemia model was established by administration of adenine. Thirty-two rats were randomly allocated into 4 groups： model group, low/high-dose TSD-treated groups, and allopurinol-treated group. Meanwhile, 8 rats were used as normal controls. Serum uric acid（UA）, blood urea nitrogen（BUN）, serum creatinine（Scr）, and organic anion transporting polypeptide 1A1（OATP1A1） levels were measured. Comparison between the model group and treatment（allopurinol and TSD） groups showed the serum UA levels were significantly decreased in treatment groups. TSD had similar effects to allopurinol. It was found that the OATP1A1 protein expression levels in treatment groups were higher than in model group and normal controls. And different from the allopurinol-treated groups, TSD-treated group had elevated OATP1A1 expression levels in the stomach, liver, small intestine and large intestine tissues. It was suggested that TSD may facilitate the excretion of UA and lower UA levels by up-regulating OATP1A1 expression.

Exploring the intercalation chemistry of layered yttrium hydroxides by 13C solid-state NMR spectroscopy

Layered rare earth hydroxides(LREHs)are a novel class of two-dimensional materials with potential applications in various fields.The exchange reactions with organic anions are typically the first step for the functionalization of LREHs.Although the laminar structures seem to be clear for anion-exchanged compounds,the state of intercalated organic anions and their interactions with cationic rare earth hydroxide layers remain unclear.Herein,we demonstrate that the use of 13C solid-state nuclear magnetic resonance(ssNMR)spectroscopy enables to extract key information on the state of intercalated organic anions such as their local chemical environment,stacking,and dynamics,which are often difficult or impossible to obtain previously.In combination with powder X-ray diffraction and ab initio density functional theory calculations,the intercalation chemistry of two representative layered yttrium hydroxides with selected monovalent organic anions was studied in detail.The products can undergo secondary exchange with a divalent organic anion,depending on the match between the basal spacing of two phases,i.e.,the replacement of benzenesulfonate(BS^(-)
),2,4-dimethylbenzene sulfonate(DMBS^(-)
),and 4-ethylbenzene sulfonate(EBS
)with 2,6-naphthalene disulfonate(NDS^(2-)
)is allowed due to the insignificant change in basal spacing after exchange,while the replacement of very long dodecyl benzene sulfonate(DBS^(-)
)and dodecyl sulfate(DS
)with NDS^(2-)is forbidden.The results therefore provide valuable insights into the structure-property relationships of LREH-based functional materials.

Evaluating the regulation of transporter proteins and P-glycoprotein in rats with cholestasis and its implication for digoxin clearance

BACKGROUND Cardiac and hepatic functionality are intertwined in a multifaceted relationship.Pathologic processes involving one may affect the other through a variety of mechanisms,including hemodynamic and membrane transport effects.AIM To better understand the effect of extrahepatic cholestasis on regulations of membrane transporters involving digoxin and its implication for digoxin clearance.METHODS Twelve adult rats were included in this study;baseline hepatic and renal laboratory values and digoxin pharmacokinetic(PK)studies were established before evenly dividing them into two groups to undergo bile duct ligation(BDL)or a sham procedure.After 7 d repeat digoxin PK studies were completed and tissue samples were taken to determine the expressions of cell membrane transport proteins by quantitative western blot and real-time polymerase chain reaction.Data were analyzed using SigmaStat 3.5.Means between pre-surgery and post-surgery in the same experimental group were compared by paired t-test,while independent t-test was employed to compare the means between sham and BDL groups.RESULTS Digoxin clearance was decreased and liver function,but not renal function,was impaired in BDL rats.BDL resulted in significant up-regulation of multidrug resistance 1 expression in the liver and kidney and its down-regulation in the small intestine.Organic anion transporting polypeptides(OATP)1A4 was up-regulated in the liver but down-regulated in intestine after BDL.OATP4C1 expression was markedly increased in the kidney following BDL.CONCLUSION The results suggest that cell membrane transporters of digoxin are regulated during extrahepatic cholestasis.These regulations are favorable for increasing digoxin excretion in the kidney and decreasing its absorption from the intestine to compensate for reduced digoxin clearance due to cholestasis.

Organic acid anions:An effective defensive weapon for plants against aluminum toxicity and phosphorus deficiency in acidic soils

Aluminum （AI） toxicity and phosphorous （P） deficiency are two major limiting factors for plant growth on acidic soils. Thus, the physiological mechanisms for AJ tolerance and P acquisition have been intensively studied. A commonly observed trait is that plants have developed the ability to utilize organic acid anions （OAs; mainly malate, citrate and oxalate） to combat AI toxicity and P deficiency. OAs secreted by roots into the rhizosphere can externally chelate Al^3＋ and mobilize phosphate （Pi）, while OAs synthesized in the cell can internally sequester Al^3＋ into the vacuole and release free Pi for metabolism. Molecular mechanisms involved in OA synthesis and transport have been described in detail. Ensuing genetic improvement for AI tolerance and P efficiency through increased OA exudation and/or synthesis in crops has been achieved by transgenic and marker-assisted breeding. This review mainly elucidates the crucial roles of OAs in plant Al tolerance and P efficiency through summarizing associated physiological mechanisms, molecular traits and genetic manipulation of crops.

Negative Charge Management to Make Fragile Bonds Less Fragile toward Electrons for Robust Organic Optoelectronic Materials

The operational stability of organic(opto)electronic devices largely depends on the intrinsic stability of organic materials on service.For organic light-emitting diode(OLED)materials,a key parameter of their intrinsic stability is the bond-dissociation energy of the most fragile bond(BDE_(f)).Although rarely involved,many OLED molecules have the lowest BDE_(f) in anionic states[BDE_(f)(−)∼1.6–2.5 eV],which could be a fatal short-slab for device stability.Herein,we separated BDE_(f)(−)from other parameters and confirmed the clear relationship between BDE_(f)(−),intrinsic material stability and device lifetime.Based on thermodynamic principles,we developed a general and effective strategy to greatly improve BDE_(f)(−)by introducing a negative charge manager within the molecule.The manager must combine an electron-withdrawing group(EWG)with a delocalizing structure,so that it can firmly confine the negative charge and hinder the charge redistribution toward fragile bonds.Consequently,the use of this manager can substantially promote BDE_(f)(−)by∼1 eV for various fragile bonds and outperform the effect reported from solely employing EWGs or delocalizing structures.This effect was verified in typical phosphine-oxide and carbazole derivatives and backed up by newly designed molecules with multiple fragile bonds.This strategy provides a new way to transform vulnerable building blocks into robust organic(opto)electronic materials and devices.

Preparation of a novel magnetic resin for effective removal of both natural organic matter and organic micropollutants

A novel, bifunctional, hypercrosslinked, magnetic resin W2 was prepared using divinylbenzene （DVB） and glycidyl methacrylate （GMA） as comonomers in three steps （i.e., suspension polymerization, amination and post-crosslinking reactions）. To evaluate the adsorption of natural organic matter （NOM） and organic micropollutants （OMPs） on the obtained resin W2, two magnetic resins W1 （the precursor of W2 before post-crosslinking） and W0 （the precursor of W1 before amination） were chosen for comparison. The results indicated that W2 would be a promising material for the removal of both NOM and OMPs from aquatic environments.