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Purpose: The purpose of this paper is to add expanded perlite (EP) immobilized microorganisms that replace part of the standard sand in mortar to improve the self-healing ability of mortar cracks and reduce the water absorption of mortar after healing. Design/methodology/approach: Bacilluspseudofirmus spores were immobilized with EP particles as self-healing agents. The effects of adding self-healing agents on the compressive strength of mortar specimens were observed. The ability of mortar specimens to heal cracks was evaluated using crack microscopic observation and water absorption experiments. The filler at the cracks was microscopically analyzed by scanning electron microscope and X-ray diffraction experiments. Findings: First, the internal curing effect of EP promotes the hydration of cement in mortar, which generates more amount and denser crystal structure of Ca(OH)2 at mortar cracks and improves the self-healing ability of mortar. Second, the self-healing ability of mortar improves with the increase of self-healing agent admixture. Adding a self-healing agent of high admixture makes the planar undulation of calcite crystal accumulation at mortar cracks more significant. Finally, the initial crack widths that can be completely healed by adding EP and self-healing agents to the mortar are 200 µm and 600 µm, respectively. Originality/value: The innovation points of this study are as follows. (1) The mechanism of the internal curing effect of EP particles on the self-healing ability of mortar cracks was revealed by crack microscopic observation tests and microscopic experiments. (2) The effect of different self-healing agent amounts on the self-healing ability of mortar cracks has been studied. (3) The effects of EP particles and self-healing agents on healing different initial widths were elucidated by crack microscopic observation tests. [ABSTRACT FROM AUTHOR]

• RSM is used for experimental design analysis and optimization. • Use the RSM model to evaluate the impact of Zeolites, CA, and water-to-binder ratio on the self-healing performance of mortar. • Determine the optimal mixing ratio to maximize the self-healing performance of the mortar. • Microanalysis reveals that Zeolites and CA change the mortar's microstructure, enhancing the crack self-healing effects. To address the issue of concrete structures being prone to crack failure, this study employs the response surface method (RSM) to evaluate the impact of adding zeolites and crystalline admixture (CA) on the self-healing performance of mortar. Initially, zeolite amount, CA amount, and the water-to-binder ratio (W/B) are considered as response factors, using ultrasonic pulse velocity (UPV), electrical resistivity, and the self-healing rate as the response target values. UPV and electrical resistivity are used to monitor self-healing process, while self-healing rate quantifies healing of cracks. Subsequently, through designing experiments with RSM, a regression model is established, achieving multi-objective optimization of the mortar self-healing rate, and experimental validation is carried out for the optimized combinations. Finally, the mechanical properties of mortar specimens are studied, and scanning electron microscopy (SEM) and X-ray diffraction (XRD) are used to analyze the microstructure and crystal phase composition of the crack healing fillers. The quadratic polynomial model has a high degree of fit, and the error between the measured and predicted values is less than 10%, indicating the reliability of RSM in determining the optimal mix parameters for mortar self-healing. The SEM and XRD results further confirm that the moisture released by zeolites promotes the activation reaction of CA, generating a larger amount and more densely structured calcium silicate hydrate (C-S-H) gel. Moreover, the research results show that although incorporation zeolites diminishes mortar specimens' strength, incorporation zeolites promotes the generation of C-S-H gel within the cracks, attributable to activation reaction of CA, ultimately promoting crack healing and improving the strength of the mortar. Based on optimization analysis, the optimal amounts of zeolites, CA, and W/B were determined to be 20%, 4%, and 0.45, respectively. [ABSTRACT FROM AUTHOR]

New heteronuclear Zn2Ln2 clusters [Zn2L2Ln2(hfac)6] (Ln = Eu (1), Tb (2) and Dy (3)) have been synthesized based on a flexible Schiff base (H2L = N,N′-bis(salicylidene)-3,6-dioxa-1,8-diaminooctane) and β-diketonate ligand (hfac = hexafluoroacetylacetonate). The structures of the isomorphous complexes 1–3 were determined by single-crystal X-ray crystallography. Photophysical studies indicate that the short intramolecular distance of Zn…Ln allows energy transfer from the Zn2L2-based sensitizers to the Eu(iii) and Tb(iii) centres; the lanthanide luminescence is indeed “lighted up” by the excitation of the zinc complex. More interestingly, white light emission was realized by codoping Eu(iii) ion into the Dy(iii) complex for the first time. [ABSTRACT FROM AUTHOR]

A Salen-type [Salen = N, N′-ethylene bis(salicylideneimine)] mononuclear lanthanide(III)-based Zn-Dy-Zn complex [Dy(ZnL)2(CH3COO)Cl2] ·CH2Cl2 ( 1) was prepared [H2L = N, N′-bis(3-ethoxysalicylidene)phenylene-1,2-diamine]. Single-crystal X-ray diffraction analysis revealed that DyIII was sandwiched between the two ZnL moieties, which was coordinated by three outer OO2 atoms and four inner N2O2 atoms from two Salen-type ligand, respectively, and an oxygen atom of acetic acid molecule completed the eight-coordinate arrangement. The continuous-shape-measures (CShMs) analysis to the DyIII coordination polyhedron revealed that the coordination environment lies among the ideal spherical triangular dodecahedron ( D2 d) and square antiprism ( D4 d), respectively, but with relative large deviation parameters. The alternative current (ac) susceptibility measurements shown that it behaved as a field-induced single-molecule magnet with relaxation energy barrier Ueff = 19 K and τ0 = 1.5 × 10-5 s. [ABSTRACT FROM AUTHOR]

Abstract: A biphenyl-linked bis-β-diketone ligand, 3,3′-bis(3-phenyl-3-oxopropanol)biphenyl (BPB) has been prepared for the syntheses of a series of dinuclear lanthanide complexes. The ligand bears two benzoyl β-diketonate sites linked by a 3,3’-biphenyl spacer. Reaction of the doubly negatively charged bis-bidenate ligand with lanthanide ions forms triple-stranded dinuclear complexes Ln2(BPB)3 (Ln=Nd (1), Sm (2), Eu (3), Yb (4) and Gd (5)). Electrospray mass spectrometry is used to identify the formation of the triple-stranded dinuclear complexes 1–5, which have been further characterized by various spectroscopic techniques. The complexes display strong visible and NIR luminescence upon excitation at ligands bands around 360nm, depending on the choice of the lanthanides, and the emission quantum yields and luminescence lifetimes of 2–3 have been determined. It shows that the biphenyl-linked ligand BPB is a more efficient sensitizer than the monodiketone ligand DBM (dibenzoylmethane), through the comparisons of Ln2(BPB)3 and Ln(DBM)3 on their photoluminescent properties. [Copyright &y& Elsevier]

Abstract: Two lanthanide coordination polymers, {[La2(bpdc)3(H2O)4]·(H2O)4} n (1) and {[Sm2(bpdc)3(H2O)2]·(H2O)5} n (2) (H2bpdc=2,2′-bipyridine-3,3′-dicarboxylic acid) have been obtained by hydrothermal synthesis. Single-crystal X-ray diffraction shows that 1 and 2 are two-dimensional network structures based on the zigzag chains which are linked by bpdc ligands, forming the first examples of binary lanthanide polymers with bpdc. It is unprecedented that the adjacent zigzag chains are symmetrical in mirror images with the arraying form of ABAB. In 1 and 2, lanthanide ion are all nine-coordinate and bpdc ligands exhibit different kinds of coordination modes. The 1-D infinite water chain in 1 and pentameric water ring in 2 have been found between lattice water molecules. Thermo-gravimetric analyses of 1 and 2 display considerable thermal stability. Photoluminescent properties of 1 and 2 are discussed. [Copyright &y& Elsevier]

NUP155 is reported to be correlated with tumor development. However, the role of NUP155 in tumor physiology and the tumor immune microenvironment (TIME) has not been previously examined. This study comprehensively investigated the expression, immunological function, and prognostic significance of NUP155 in different cancer types. Bioinformatics analysis revealed that NUP155 was upregulated in 26 types of cancer. Additionally, NUP155 upregulation was strongly correlated with advanced pathological or clinical stages and poor prognosis in several cancers. Furthermore, NUP155 was significantly and positively correlated with DNA methylation, tumor mutational burden, microsatellite instability, and stemness score in most cancers. Additionally, NUP155 was also found to be involved in TIME and closely associated with tumor infiltrating immune cells and immunoregulation-related genes. Functional enrichment analysis revealed a strong correlation between NUP155 and immunomodulatory pathways, especially antigen processing and presentation. The role of NUP155 in breast cancer has not been examined. This study, for the first time, demonstrated that NUP155 was upregulated in breast invasive carcinoma (BRCA) cells and revealed its oncogenic role in BRCA using molecular biology experiments. Thus, our study highlights the potential value of NUP155 as a biomarker in the assessment of prognostic prediction, tumor microenvironment and immunotherapeutic response in pan-cancer. [ABSTRACT FROM AUTHOR]

Microbial-induced calcium carbonate precipitation (MICP) is utilized to effectively seal microcracks in concrete. In this study, coconut shell charcoal was used as a carrier for adsorbed bacteria to act as a biomass self-healing agent, and the healing effect of microbial mortar was enhanced by the addition of basalt fibers. The effect of the combined action of biomass self-healing agents and fibers on the mechanical properties and healing ability of mortars has been investigated. The complete process of microbial metabolism in the cement matrix was firstly revealed by microscopic experiments. Optical microscopy was used observed the deposition paths of the fillers under multifiber conditions at different depths. The results showed that a large number of fibers changed the healing products that transformed from two-dimensional to three-dimensional due to the bridging effect between the calcium carbonate grown on the neighboring fibers, which enhanced the healing ability of the cracks. • A first work about the complete process of bacterial metabolism is found by SEM test. • Reveal the microcosmic mechanism of MICP technology. • Multiple numbers of fibers change deposition of CaCO 3 from two to three-dimensional to enhance the healing ability. • A new test device is designed to quantitatively measure the depth of healed cracks. • Mortar specimens mixed with biomass self-healing agents and basalt fibers have greater mechanical properties. [ABSTRACT FROM AUTHOR]

The syntheses of pure wheel-like 4f lanthanide complexes are challenging because of the variable and high coordination numbers as well as poor directionality of the lanthanide ions. Therefore, a multifunctional ligand, salicylhydroxamic acid (H3shi), with various coordination sites is deliberately selected for the construction of lanthanide complexes. At the same time, it is found that the ligand can successfully sensitize the lanthanide centers, exhibiting their characteristic emission. A series of wheel-like complexes are synthesized by using metal to ligand stoichiometry (Ln : H3shi : 2-pyca) with a ratio of 1 : 1 : 2, namely, [Ln6(H2shi)6(2-pyca)12(CH3CN)4] ({Ln6}; Ln = Nd, Sm–Er, and Yb). Single-crystal X-ray diffraction shows that the {Eu6} complex is formed as a hexatomic core with dimensions of approximately 18 × 18 × 13 Å. The powder X-ray diffraction analysis demonstrates that all other isolated complexes are isostructural. The analysis of the luminescence properties of these complexes shows typical metal-centered emission bands from the visible (Sm3+, Eu3+, Tb3+ and Dy3+) to near-infrared (Nd3+, Ho3+, Er3+ and Yb3+) ranges. {Sm6} and {Tb6} exhibit orange and bright-green emission in the visible region, respectively. {Eu6} and {Dy6} exhibit co-luminescence of the corresponding Ln3+ ions and the ligands. {Nd6}, {Ho6}, {Er6} and {Yb6} exhibit characteristic sharp emission bands in the NIR range. [ABSTRACT FROM AUTHOR]

A series of dinuclear dysprosium complexes bridged by pyridine-NO ligands with formula [Ln2(BTA)6(pyNO)2] (1Dy, Ln = Dy, 1Y, Ln = Y and 1Gd, Ln = Gd) (BTA = benzoyltrifluoroacetone, pyNO = pyridine-N-oxide) were structurally and magnetically characterized. The X-ray crystallographic analyses of the structures revealed that the NO group serves as the effective bridge to link two Dy(iii) centers and the periphery β-diketonate (BTA) ligands complete the rest of the coordination sphere. The dynamic magnetic measurements revealed that complex 1Dy displayed significant zero-field single-molecule magnetic (SMM) behaviour with 72 K energy barrier and 2.5 K hysteresis temperature. In order to extend this dinuclear system, double N-oxide bridged ligand 4,4′-bpdo(4,4′-bipyridine-N,N′-dioxide) was used, and consequently, a series of one-dimensional chain complexes possessing repeated [Ln2(BTA)6(pyNO)2] units were synthesized with formula [Ln2(BTA)6(4,4′-bpdo)]n·2EtOH (2Dy, Ln = Dy, 2Y, Ln = Y and 2Gd, Ln = Gd). The AC magnetic susceptibility measurements revealed that complex 2Dy exhibited significant zero-field slow magnetic relaxation behavior with a higher effective energy barrier of 87 K and a hysteresis temperature of 3 K than 1Dy albeit the separation between the repeated units is large. [ABSTRACT FROM AUTHOR]

A dinuclear dysprosium complex, [Dy2(tta)6(4‐mepyNO)2]·CHCl3 (tta = thenoyltrifluoroacetone, 4‐mepyNO = 4‐methylpyridine N‐oxide), has been structurally and magnetically characterized. Analysis of the single‐crystal structure revealed that the NO group serves as an effective bridge to link the two DyIII centres and combine with the peripheral β‐diketonate ligands to form an eight‐coordinate geometry of DyIII. Magnetic measurements showed significant zero‐field single‐molecule magnetic behaviour with a 3 K hysteresis temperature and 121 K energy barrier. Diamagnetic dilution studies revealed that the DyIII–DyIII coupling suppresses the quantum tunelling of magnetization, although the coupling is generally weak. The diluted system mainly displays decoupling single‐ion magnetic anisotropic behaviour with a higher hysteresis temperature of 3.5 K. [ABSTRACT FROM AUTHOR]

Abstract: Crystal structures, single‐molecule magnetic behavior, and ab initio calculations of four new phenoxo‐bridged dinuclear dysprosium complexes and their gadolinium(III) analogues are explored. Complexes [Dy2(DMOMP)2(DBM)4]2⋅CHCl3 (1; DMOMP=1‐methyl‐3,5‐dimethoxy‐4‐hydroxybenzene, DBM=1,3‐diphenylpropane‐1,3‐dione); [Dy2(DMOAP)2(DBM)4]2⋅CHCl3 (2; DMOAP=syringaldehyde); Dy2(DMOEP)2(DBM)4 (3; DMOEP=methyl syringate); and solvent‐free Dy2(DMOMP)2(DBM)4 (4), which is obtained by the transformation of single crystal into single crystal from 1, have nearly identical core structures and only differ in the substituents at the para position of the phenol moieties of the bridging ligand. In this system, the electronic effects are efficiently implemented to significantly modify the ligand field strength and exchange coupling by modulating the substituents on the phenol backbone. The effective energy barrier (Ueff) of magnetization reversal is improved significantly to fivefold magnitude, at most, and the hysteresis temperature up to 3.5 K by deliberately using the electron‐withdrawing substituent to replace the electron‐donating one. The origin of the two relaxation processes in 1 is mostly attributed to the existence of two molecules in one unit, which is illuminated by means of the transformation of single crystal into single crystal. [ABSTRACT FROM AUTHOR]

The synthesis, structural characterization and magnetic properties of four heterometallic complexes with formulas Ln2M(OQ)8 [Ln(iii) = Dy, M(ii) = Ca (1), Mg (2); Ln(iii) = Er, M(ii) = Ca (3), Mg (4); HOQ = 8-hydroxyquinoline] are reported. Complexes display a perfectly linear arrangement of three metal ions involving two terminal Ln(iii) ions and one central alkaline earth M(ii) ion, and they are bridged by three phenolato oxygen atoms from three 8-hydroxyquinoline ligands. Direct-current (dc) magnetic susceptibility studies show that there exists a long-range ferromagnetic (FM) interaction between two f-electronic centers in Dy-based complexes 1 and 2 albeit they are separated by diamagnetic alkaline earth ions, and the FM interaction has been successfully reproduced by ab initio calculations. Alternating current (ac) magnetic susceptibility measurements indicate that complexes 1 and 2 exhibit significant single-molecule magnet (SMM) behaviors. This is mostly attributed to the parallel magnetic axes of individual Dy(iii) sites aligning closely to the Dy–M–Dy direction, and the linearly extending magnetic susceptibility tensors of each ion lead to the FM interaction. The dc and ac susceptibility studies of the intramolecularly diluted complexes reveal that the f–f coupling suppresses the QTMs significantly in the absence of the external magnetic field. [ABSTRACT FROM AUTHOR]

We successfully explored for the first time that trifluoroacetic acid (TFA) can effectively catalyze the oxa-Pictet-Spengler reaction of secondary tryptophols and acetals to synthesize 1,3-disubstituted 1,3,4,9-tetrahydropyrano[3,4- b ]indoles in high yield (up to >99%) and diastereoselectivity (>20:1). The secondary tryptophols were synthesized from indole-3-acetic acid. The one-pot synthesis of tetrahydropyrano[3,4- b ]indoles was successfully developed from secondary tryptophols and in situ prepared acetals from aldehydes and trimethylorthoformate and thus the cost-efficiency of the protocol was effectively enhanced. Finally, the catalytic asymmetric synthesis of the 1,3-disubstituted tetrahydropyrano[3,4- b ]indole was also demonstrated after enantioselective achievement of highly enantiopure secondary tryptophols. [ABSTRACT FROM AUTHOR]

A series of new isostructural lanthanide(iii) complexes are reported which are constructed from Schiff base and β-diketonate ligands, namely, [Ln2(DBM)6(L)] (Ln = Sm (1), Eu (2), Gd (3), Dy (4), Yb (5); L = N,N′-bis(pyridin-2-ylmethylene)ethane-1,2-diamine, DBM = dibenzoylmethanide). The structures of the isomorphous complexes 1–5 were determined by single-crystal X-ray crystallography. The two Ln(iii) ions in the molecules of 1–5 are bridged by a Schiff base ligand that displays a curved configuration. Complexes 1, 2 and 5 exhibit lanthanide ion-based luminescence not only in the solid state but also in methanol solution. The lifetimes and quantum yields of luminescence were also determined. The magnetic analysis reveals that complexes 4 and 5 exhibit field-induced single-molecule magnet behavior with energy barriers (Ueff/kB) of 46.8 and 23.0 K at direct current fields of 2000 Oe, respectively. [ABSTRACT FROM AUTHOR]

A series of HMq-bridged dinuclear dysprosium complexes, namely, [Dy(acac)2(CH3OH)]2(μ-HMq)2 (1), [Dy(DBM)2]2(μ-HMq)2(n-C6H14) (2), [Dy(hmac)2]2(μ-HMq)2 (3) and [Dy(hfac)3]2(μ-HMq)2 (4) (HMq = 2-methyl-8-hydroxyquinoline, acac = acetylacetone, DBM = dibenzoylmethane, hmac = hexamethylacetylacetonate and hfac = hexafluoroacetylacetonate), were structurally and magnetically characterized. X-ray crystallographic analyses of the structures reveal that HMq serves as the effective bridge to link two Dy(iii) centers by means of the phenoxyl oxygen and nitrogen atoms and the periphery β-diketonate ligands complete the coordination sphere by bidentate oxygen atoms. The different substituents on the β-diketonate terminal lead to different coordination models mostly due to the steric hindrance of these substituents, and the electron-withdrawing or donating effects likely influence the strength of the ligand fields and the Dy(iii) ion anisotropy. Measurements of alternating-current (ac) susceptibility on complexes 1–4 reveal that complexes 3 and 4 display significant zero-field single-molecule magnetic (SMM) behavior with barrier energy Ueff/kB = 14.8 K, τ0 = 1.8 × 10−5 s and Ueff/kB = 9.2 K, τ0 = 1.7 × 10−5 s, respectively, whereas 1 and 2 exhibit field-induced SMM behavior, and these differences are attributed to the alteration on the periphery β-diketonate ligands. Their distinct slow magnetic relaxation behaviors were related to their different individual Dy(iii) ion magnetic anisotropy and intramolecular coupling, which were confirmed by ab initio calculations. [ABSTRACT FROM AUTHOR]

The paper studies the magnetic field distribution of three degree-of-freedom (3-DOF) permanent magnet (PM) spherical motor adopting the 3-D magnetic equivalent circuits (MEC) method. Compared with the analytical method and finite element analysis (FEA) method, the MEC has such desirable attributes as moderate computational effort and reasonable accuracy. The model of PM spherical motor is evenly meshed into elements in spherical coordinates, and the expressions of reluctances and magnetomotive force (MMF) sources in the element have been deduced. Given that magnetic field of the PM spherical motor distributes in the whole space, to reduce the number of elements and increase the solving speed, an approximate equipotential surface is adopted based on the simplified magnetic circuit, and the different magnetic boundary conditions are represented by the corresponding states of nodes and branches of the elements. Finally, the MEC network, which represents half of the magnetic pole and the corresponding air region of the motor, is built. Flux density distribution is calculated by means of the proposed model and verified by the FEA method. [ABSTRACT FROM PUBLISHER]

Abstract: Diaryl ethers have been prepared by a mild and efficient SNAr reaction by coupling of various phenols including that having a electron-withdrawing group with activated fluoroarenes using sonication in good to excellent yields at very low temperature (58°C) under catalyst-free. [Copyright &y& Elsevier]

A novel family of lanthanide compounds with a 1-D chain structure [Ln2L(TTA)4(OAc)2]n [Ln = Sm (1), Eu (2) Gd (3) and Yb (4)] was constructed from β-diketonate (TTA = 2-thenoyltrifluoroacetone) and an auxiliary ligand Schiff base (H2L = N,N′-bis(salicylidene)butane-1,6-diamine). The structures of the isostructural complexes 1–4 were determined via single-crystal and powder X-ray crystallography. The optical properties of these compounds could be simply enhanced using a doping method, enabling the doped materials with tunable visible and near-infrared emission. The quantum yields of the doped samarium and europium compounds reached 6.8% and 76.2%, respectively, which were higher compared with other previously reported studies. Subsequently, a multifunctional sensor was employed to detect CH3COOH and poisonous HS− anions. The notable quenching effect proved that this doped material is a promising fluorescence probe for the sensing of anions and organic small molecules with high identification ability and sensitivity. Moreover, the possible mechanism for luminescence sensing has been studied in detail. [ABSTRACT FROM AUTHOR]

A series of {Ln 2 } have been prepared, and typical visible-infrared and magnetic behavior are detected in respect to the central Ln3+ ions. • A series of bifunctional dinuclear complexes have been synthesized. • High quantum yield and long luminescence life are found in {Eu2}. • Magnetization measurement indicate that 3 shows single molecule magnetic behavior. A series of bifunctional [Hpy] 2 [Ln 2 (NO 3) 2 (ampy) 4 (H 2 shi) 2 ] ({Ln 2 } ; Ln = Eu(1), Gd(2) and Dy(3); H 3 shi = salicylhydroxamic acid; Hampy = 5-aminopyridine-2-carboxylic acid) have been synthesized and characterized. Single-crystal X-ray diffraction analyses reveal that complexes 1 and 3 are isostructural. The complexes {Ln 2 } exhibit either photophysical or magnetic properties in respect to the central lanthanide ion. It is rarely observed that 1 gives bright and red emission with high quantum yield (16%) and a long luminescence lifetime (547 μs). Magnetic measurement reveals that 3 exhibits significant single molecule magnet behavior with an effective energy barrier of 31 K. [ABSTRACT FROM AUTHOR]

A tetradentate 8-hydroxyquinoline-based acyl hydrazone ligand (HL1 = 8-hydroxyquinoline-2-carboxaldehyde-(aminourea)hydrochloride) was elaborately used to construct a mononuclear dysprosium complex DyCl3HL1·CH3OH (1) with a nearly ideal pentagonal bipyramid coordination geometry (D5h) surrounding the Dy(iii) ion to achieve the significant performance of single-molecule magnets (SMMs). Meanwhile, the isolated high local symmetry center was successfully kept intact and further bridged to a series of double bipyramid systems by two phenolic oxygen atoms of the acyl hydrazone ligands (HL1 and HL2 = 8-hydroxyquinoline-2-carboxaldehyde-(benzoyl)hydrazine), with the formulae [Dy2Cl4(L1)2(CH3OH)2]·4C5H5N (2) and [Dy2Cl4(L2)2]·2CH3CN (3). In addition, the monodentate co-ligand anion was replaced by a larger sterically hindered ligand and a bidentate monovalent β-diketonate anion to generate [Dy2(tfo)4(L2)2(EtOH)2] (4), [Dy2(tta)4(L2)2(EtOH)2]·2(EtOH) (5) and [Dy2(dbm)4(L2)2(EtOH)2] (6) (tfo = trifluoromethanesulfonic acid, dbm = dibenzoylmethane, tta = 4,4,4-trifluoro-1-(2-thienyl)-1,3-butanedione) with eight-coordinate geometry. Strikingly, the dynamic magnetic measurements revealed that complexes 1–3 did not display the expected significant SMM performance albeit they had high local symmetry. In combination with ab initio calculation, the alignment of the coordination symmetric axis and the magnetic easy axis dominates the molecular magnetic anisotropy, and the magnetic easy axis could be modulated by the distribution of coordination atoms with different electrostatic properties. [ABSTRACT FROM AUTHOR]

A new series of dinuclear lanthanide complexes, Ln2(Hshi)2DBM4·2DMF (Ln = Sm, Eu, Gd, Dy, Nd and Yb) were synthesized using H3shi (H3shi = salicylhydroxamic acid) and a β-diketonate ligand (DBM = dibenzoylmethanide). The two Ln(iii) ions in the molecules are bridged by a salicylhydroxamic ligand with a rigid configuration. The structures of the isostructural complexes 1–6 were determined by single-crystal X-ray crystallography. The optical properties of the complexes can be simply enhanced by doping methods. White-light emission materials can be obtained from a single component (Sm3+) by adjusting the excitation wavelength. The lifetimes and quantum yields of the luminescence were also determined. [ABSTRACT FROM AUTHOR]

Two dinuclear dysprosium complexes with the Dy(iii) ions bridged by the neutral bipyrimidine (BPYM) ligand were synthesized and magnetically characterized. They crystallized in a monoclinic and triclinic crystal system, respectively, with almost the same structural core, only differing in the lattice solvent molecules. Alternating current (ac) susceptibility measurements revealed that they exhibit significant slow relaxation of magnetization until 25 K in the absence of a dc field. The single and double relaxation processes were assigned to one and two types of Dy(iii) environments in the two dimmers, respectively, with barriers of 266 and 345 K under zero field conditions. The magnetic hysteresis loops of 1 and 2 were both observed up to 2.5 K. [ABSTRACT FROM AUTHOR]

Three complexes with formula {Dy(q)2(L)}2(μ3-OH)2{Dy(q)(L)}2(solvents) (where q = 8-quinolinolate; L = acetylacetone (acac) with (CH2Cl2)2 = solvent (1), 1,3-diphenyl-1,3-propanedione (DBM) and (CH2Cl2)2 = solvent (2), and hexafluoroacetylacetone (hfac) and CHCl3 = solvent (3)) were structurally and magnetically characterized. They have similar Dy4 structural cores bridged by N and O atoms from 8-quinolinolate, and only differ in the peripheral β-diketonate ligands. The variable-frequency and temperature alternating-current (ac) magnetic susceptibility measurements reveal that complexes 1 and 2 display significant zero-field single-molecule-magnet (SMM) behavior, while complex 3 exhibits the field-induced SMM behavior, albeit they possess the nearly same primary coordination sphere. The ac susceptibility measurement on the diluted samples verified that their relaxation was of purely molecular origin, and their distinct slow magnetic behaviors were related to the replacement of the peripheral β-diketonate ligand, which is responsible for their different individual Dy(iii) ions’ magnetic anisotropy and intramolecular coupling, as confirmed by ab initio calculation. [ABSTRACT FROM AUTHOR]

Two lanthanide complexes are achieved by utilizing H 2 salen/acac ligands (H 2 salen = N , N′ -ethylenebis(salicylideneimine), acac = acetylacetonate). They are homonuclear [Nd 4 ( μ 3 -OH) 2 (salen) 2 (acac) 6 (CH 3 OH) 2 ]·CH 3 OH ( 1 ) and heteronuclear [NdYb(salen) 2 (acac) 2 ] ( 2 ). The structures of the two complexes were determined by X-ray crystallographic studies and their photophysical properties were investigated. The homonuclear Nd 4 complex exhibits characteristic metal-centered NIR emission. The heteronuclear NdYb shows ‘dual emission’ from both neodymium(III) and ytterbium(III) ions. [ABSTRACT FROM AUTHOR]

The chemical fixation of CO2 with epoxides to form cyclic carbonates was carried out with excellent selectivity and yield in the presence of Brønsted acidic ionic liquids without using additional organic solvents and co-catalyst. The acidic strength of ionic liquids was determined and its effect on the synthesis of cyclic carbonates was investigated. The reaction conditions (temperature, CO2 pressure and reaction time) were optimized, and the Brønsted acidic ionic liquids showed highly catalytic activity under the optimal reaction conditions. A plausible reaction mechanism was suggested and it was demonstrated that the carboxylic group in Brønsted acidic ionic liquids had synergetic effect with halide. Moreover, the catalyst could be used five times without significant decrease in its catalytic activity. [ABSTRACT FROM AUTHOR]

Three dinuclear [Ln2H2OL12(acac)2]·solvent (1, Ln = Gd, solvent = 2CH2Cl2; 2, Ln = Tb, no solvent; 3, Ln = Er, solvent = (C2H5)2O), and two tetranuclear lanthanide clusters [Ln4(μ3-OH)2L22(acac)6]·2(solvent) (4, Ln = Tb, solvent = CH3OH; 5, Ln = Dy, solvent = CH3CN) were characterized in terms of structure, fluorescence and magnetism. The dinuclear lanthanide complexes were constructed by a rigid salen-type ligand H2L1 = N,N′-bis(salicylidene)-o-phenylenediamine and β-diketonate (acac = acetylacetonate) ligands, while the tetranuclear clusters were formed from the flexible ligand H2L2 = N,N′-bis(salicylidene)-1,2-ethanediamine. Crystal structure analysis indicates that the rigid ligand favors the double-decker sandwich structure (Ln2L12), in which the two lanthanide ions have different coordination numbers and geometry, while the more flexible ligand (H2L2) leads to planar tetranuclear clusters. The relationship between their respective magnetic anisotropy and ligand-field geometries and their fluorescence properties was investigated. The Dy and Tb-containing clusters exhibit typical visible fluorescence properties, and single-molecule magnet behavior is seen in complex 5. [ABSTRACT FROM AUTHOR]

The health effects of odors emitted from the human environment have received some discussion in the literature. Little has been written, however, about the health effects of odor emissions from renovation. The authors therefore conducted a cross-sectional study with a simple randomized sampling design. The sample was selected from a building-and-construction registry that registered all building and domestic renovation applications in Tianjin, China. Information on demographics, physical symptoms, and health status was collected via personal interviews. Air samples were also collected from each household for chemical analysis. Data were analyzed with weighted logistic-regression models. A significant association was found between exposure to odor emission and unspecific physical symptoms. After potential confounders were adjusted for, it was found that people who had been exposed to moderate-to-strong odor emissions from renovations were about four times more likely to report experiencing unspecific discomfort than were people who had been exposed to weak odor emissions (odds ratio = 4.05; 95 percent confidence interval = 1.49-11.03). The results indicate that odor emissions from domestic renovation have a detrimental effect on human physical health. This effect seemed to be independent from that generated by chemicals. Implications and prevention strategies are discussed. [ABSTRACT FROM AUTHOR]