Search

The in-situ formed Li–B alloy provides abundant nucleation sites for inducing uniform Li deposition and inhibiting Li dendrite formation. The 3D porous Ni foam can provide enough space for relieving volume change.

C40H19EuF8N4O9, triclinic, P 1 ‾ $P\overline{1}$ (no. 2), a = 11.3326(4) Å, b = 12.7652(4) Å, c = 13.2629(4) Å, α = 102.266(2)°, β = 97.689(2)°, γ = 105.630(3)°, V = 1767.93(10) Å3, Z = 2, R gt (F) = 0.0329, wR ref (F 2) = 0.0648, T = 293(2) K.

C80H38Dy2F16N8O18, triclinic, P 1 ‾ $P\overline{1}$ (no. 2), a = 11.3924(5) Å, b = 12.7091(4) Å, c = 13.2583(5) Å, α = 102.496(3)°, β = 97.955(4)°, γ = 105.588(4)°, V = 1765.36(12) Å3, Z = 2, Rgt (F) = 0.0298, wRref (F 2) = 0.0606, T = 293(2) K.

C21H11F4NO4, triclinic, P 1 ‾ $P\overline{1}$ (no. 2), a = 9.5000(4) Å, b = 13.9989(7) Å, c = 14.1423(5) Å, α = 91.355(4)°, β = 108.542(4)°, γ = 98.958(4)°, V = 1756.02(14) Å3, Z = 4, R gt (F) = 0.0494, wR ref (F 2) = 0.1157, T = 293(2) K.

Lithium (Li) metal has been considered to be the most promising anode material for next-generation rechargeable batteries. Unfortunately, the hazards induced by dendrite growth and volume fluctuation hinder its commercialized application. Here, a three-dimensional (3D) current collector composed of a vertically aligned Cu

Ear architecture is determined by two stable heritable traits, kernel row number (KRN) and kernel number per row (KNPR), but its relationship with drought resistance is still vague. To this end, we obtained 16 and 11 hybrids with slender (less KRN but more KNPR) and stubby (more KRN but less KNPR) ears by intentionally crossbreeding, respectively. These hybrids were exposed to a seven-day water deficit (WD) since silk emergence coupled with synchronous (SP) and continuous pollination (CP) to alter the pollination time gaps on ears. The results showed that the emerged silks in CP were 9.1 and 9.0% less than in the SP treatment in the stubby and slender ears, respectively, suggesting the suppression of asynchronous pollination on silk emergence. The stubby ears performed higher silking rate and yield compared with the slender ears with or without drought stress. To eliminate the inherent difference in sink capacities, we selected four hybrids for each ear type with similar silk and kernel numbers for further analyses. Interestingly, the stubby ears were less affected in silking rate and thus performed higher yield under drought compared with the slender ears. The finding suggests that ear architecture matters in the determination of drought resistance that deserves more attention in breeding.

Covalent organic frameworks (COF) possess a robust and porous crystalline structure, making them an appealing candidate for energy storage. Herein, we report an exfoliated polyimide COF composite (P-COF@SWCNT) prepared by an in situ condensation of anhydride and amine on the single-walled carbon nanotubes as advanced anode for potassium-ion batteries (PIBs). Numerous active sites exposed on the exfoliated frameworks and the various open pathways promote the highly efficient ion diffusion in the P-COF@SWCNT while preventing irreversible dissolution in the electrolyte. During the charging/discharging process, K

A Co(II) complex, Co(H2dppc)2(H2O)2 (1) and a Cu(II) compex, Cu(H2dppc)2 (2) (H3dppc = 3-(2,4-dicarboxylate phenyl) -2-pyridinecarboxylic acid) have been synthesized and characterized by IR, elemental analysis, single-crystal X-ray diffraction and Hirshfeld analysis methods. The magnetic properties of the two complexes are also studied. For complex 1, the Co(II) ion is coordinated by two water molecules and two deprotonated H3dppc ligands in N-O chelate mode to form a mononuclear complex; for complex 2, the Cu(II) ion is coordinated by two deprotonated H3dppc ligands in μ2-η2:η1 mode to form a mononuclear complex; the two complexes are both connected into 3D supramolecules by intermolecular O-H⋯O and C-H⋯O hydrogen bonds. Hirshfeld surface analysis and 2D fingerprint plots are used to calculate the contribution of different intermolecular interactions. This work could provide a new strategy for the rational design and synthesis of supramolecules.

Two nickel (II) complexes, [Ni(Hcdcp) (H2O)3] (1) (H3cdcp = 3-(4-carboxylatephenyl)-2,6-pyridinedicarboxylic acid) and [Ni3(Hdcdcp)2(H2O)6]n (2) (H4dcdcp = 3-(2,4-dicarboxylatephenyl)-2,6-pyridinedicarboxylic acid) have been synthesized under hydrothermal conditions and characterized by elemental analysis and single-crystal X-ray diffraction. For complex 1, Ni(II) ion is coordinated by three water molecules and a deprotonated H3cdcp ligand in chelate mode to form a mononuclear complex; for complex 2, three Ni(II) ions are connected into trinuclear clusters which are further linked into 2D layers by pentadentate Hdcdcp3− ligands in alternant bis-(bridging) and chelate coordination modes; the two complexes are both extend to 3D supramolecular polymers by hydrogen bonds. Thermogravimetric analysis (TGA) and powder X-ray diffraction (PXRD) are also carried out to determine their thermal stability and phase purity. Magnetic measurement for complex 2 reveals that weak antiferromagnetic interactions occur between the bridging trinuclear Ni( II ) ions.

Three lanthanide compounds have been synthesized, namely, {[Dy2(bpda)3(H2O)3]4·2H2O}(Dy-1), {[Sm(bpda)2·(H2O)]·H2O}n (Sm-2) and {[Tb2(bpda)3(H2O)3]4·2H2O} (Tb-3) (H2bpda = 2,2′-bipyridine-6,6′-dicarboxylic acid). Their structures were determined by single crystal X-ray diffraction and characterized by elemental analysis, infrared spectroscopy and thermogravimetric analysis. Dy-1 and Tb-3 are isostructural with a conjugate bimolecular four-nuclear cluster structure constructed with intramolecular hydrogen bonds and they form a 3D supramolecular structure with intermolecular hydrogen bonding. Sm-2 is a one-dimensional chain structure and is further connected by intricate hydrogen bonds into a three-dimensional supramolecular structure. These three compounds exhibit significant characteristic luminescence from the ligand to the central Ln(III) ion, which is found by solid-state photoluminescence measurement. Sm-2 exhibits a long luminescence lifetime and high fluorescence quantum yield. A slow relaxation phenomenon is observed for the dysprosium compound by measuring the alternating-current susceptibility at low temperature and the underlying mechanism was further confirmed by theoretical calculations.

A luminescent europium metal-organic framework[Eu(Hbptc)(H2O)3]n (1) has been successfully prepared by the facile hydrothermal reaction of Eu(NO3)3 ⋅ 6H2O and the π-conjugated ligand H4bptc (H4bptc = biphenyl-2,3,3′,5′-tetracarboxylic acid). Single crystal structure analysis reveals that 1 exhibits a 2D layered structure. The luminescence studies revealed that this material can be selectively and sensitively quenched or enhanced by some small organic molecule solvents, showing potential as fluorescence probe.

A new 1-D calcium complex [Ca(H2bptc)(H2O)3]n (1) (H4bptc = biphenyl-2,3,3′,5′-tetracarboxylic acid) were obtained by hydrothermal reaction. X-ray diffraction analysis shows that complex 1 crystallizes in the monoclinic space group P2(1)/c with a = 14.3376(13), b = 11.3116(10), c = 11.9099(11), β = 114.0740(10), V = 1763.6(3)A3, Z = 4, Dc = 1.591 g·cm−3, μ = 0.417 mm−1, F(000) = 872, and the final R1 = 0.0310, wR2 = 0.0812 for I>2σ(I). Central Ca(II) ion is seven-coordinated and exhibits a distorted pentagonal bipyramidal geometry. Additionally, the IR, TG, UV-Vis absorption, and luminescence properties of 1 have been investigated.

Reaction between silver salt and conjugational N-hetrocyclic carboxylic acid with the presence of bipyridyl skeletons auxiliary ligand afforded a d10 metal polymer namely [(ddpp)Ag(bipy) (1)] (ddpp = 2, 5-di(2′,4′-dicarboxylphenyl)pyridine, bipy = 4,4′-bipyridine). It was characterized by elements analysis, infrared spectroscopy, single crystal X-ray diffraction and thermogravimetry studying. For the polymer 1, silver centers are three coordinated geometry with an ON2 donor set provided by ddpp and bipy. The polymer 1 is built from 1-D alternative/zig-zag chain, as the secondary building unit, and further stacks via hydrogen bonds which formed between two isophthalic moieties of ddpp ligands and weak interactions to generate a two-dimensional, 2D supramolecular layer. Moreover, the polymer 1 displays thermal stability in solid state and the luminescence behaviour is also investigated in a dimethyl sulphoxide solution at ambient temperature, and it also can be applied in design of sensors to detect of trace aluminum, zinc and calcium ion.

Correction for ‘Lanthanide complexes based on a conjugated pyridine carboxylate ligand: structures, luminescence and magnetic properties’ by Rong-fang Li et al., RSC Adv., 2020, 10, 6192–6199.

The reactions in mixtures of lanthanide oxides and biphenyl-2,3,3′,5′-tetracarboxylic acid, in the presence of aqueous solution, result in two interesting lanthanide–organic coordination polymers, formulated as{[Eu(Hbptc)(H2O)4]·H2O}n (1) and [Sm(Hbptc)(H2O)3]}n (2), (H4bptc = biphenyl-2,3,3′,5′-tetracarboxylic acid). The polymers 1 and 2 are built from 2D corrugated layer. The 2D layers are further interconnected to form the 3D framework by hydrogen bonds between water molecules and carboxyl groups. Both the complexes 1 and 2 exhibit efficient sensitized luminescence in the visible region in the solid state based on characterization emission of europium(III) and samarium(III) ions, respectively.

Hydrothermal reactions of biphenyl-2,3,3′,5′-tetracarboxylic acid (H4bptc) with manganese salt in the presence of 1,4-bis(2-pyridylmethyl)piperazine (bpmp) afforded one novel coordination polymer, namely, [Mn2(bptc)(bpmp)0.5]n (1). Its structure was established by single-crystal X-ray diffraction analysis and further characterized by elemental analysis, IR spectra and TG analysis. Complex 1 contains {Mn4} cluster, exhibiting an unusual mode of two-fold interpenetrating three-dimensional (3D) framework with a (3, 8)-connected (84.102) (4.7.84.102.11.15) topology. In addition, magnetic susceptibility measurements indicate that complex 1 show weak antiferromagnetic interactions between the adjacent manganese ions.

Hydrothermal reactions of biphenyl-2,3,3′,5′-tetracarboxylic acid (H4bptc) with zinc salts in the presence of 1,4-bis(2-pyridylmethyl)piperazin (bpmp) and 4,4-dipyridyl (dpy) afforded the coordination polymers {[Zn2(bptc)(bpmp)]·3H2O}n (1) and {[Zn(H2bptc)(dpy)]·3H2O}n (2). Their structures were determined by single-crystal X-ray diffraction analysis and further characterized by elemental analysis, IR spectroscopy, and TG analyses. Complex 1 displays an unusual three-dimensional (3D) supramolecular motif generated by hydrogen bonding interactions between two single-layered 2D networks. Complex 2 represents a 2D layer structure, and such layers are further united together into three-dimensional supramolecular structure through intricate hydrogen bonding. In addition, luminescence properties of complexes 1 and 2 were also investigated.

Novel, freestanding membranes composed of SiO2@Bi2O3 hierarchical core/shell fibers were prepared by a combination of two fabrication methods: electrospinning and hydrothermal reaction. The SiO2@Bi2O3 composite membranes were primarily supported by flexible SiO2 fibers after the calcination treatment of electrospun PVA/SiO2 hybrid fibrous membranes. SiO2@Bi2O3 composite fibers were fabricated via a process that entails hydrothermal growth of a bismuth precursor nanocoating (Bi-PN) on the surface of SiO2 fibers followed by the thermal treatment of the harvested SiO2@Bi-PN fibers. It was observed that Bi2O3 nanoparticles were well anchored on the surface of SiO2 fibers and the phase transition of Bi2O3 nanoparticles occurred during the thermal treatment of SiO2@Bi-PN composite fibers at different temperatures. The infrared emission rates of the resultant SiO2@Bi2O3 composite membranes were evaluated in comparison with pure SiO2 fibers in 2–22 μm wavebands. It is theorized that the coating of Bi2O3 nanoparticles contributes to the decrease of infrared emissivity, and the infrared emission properties of SiO2@Bi2O3 composite fibers are related to the α-Bi2O3 phase. The results favourably indicated prospects of SiO2@Bi2O3 composite fibrous membranes for applications in infrared stealth camouflage.

C16H13O11Pr, triclinic, P1̅, a = 6.915(3) Å, b = 10.895(4) Å, c = 11.644(4) Å, α = 94.137(5)°, β = 101.152(5)°, γ = 96.831°, V = 850.61(5) Å3, Z = 2, R gt(F) = 0.0352, wR ref(F 2) = 0.0737, T = 293(2)K.

Two metal–organic frameworks [Mn4(bptc)2(bpy)2]n (1) (H4bptc = biphenyl-2,3,3′,5′-tetra-carboxylic acid, bpy = 2, 2′-dipyridine) with Mn4 clusters and {[Mn2(bptc)2(H2O)8]⋅4H2O}(2) were obtained through hydrothermal reaction. X-ray diffraction analysis shows that both complexes 1 and 2 crystallize in the Triclinic system, space group of P-1. The Mn(II) ions have two kinds of coordination mode in complex 1, one is five- coordinated and the other is six-coordinated. Mn(2) ion is bridged to neighboring Mn(2)A(A:1 − x, 1 − y, 2 − z) by two μ2-Ocarboxyl atoms to afford a {Mn}4 cluster together with another two symmetrical Mn(1) and Mn(1)a. The {Mn}4 clusters are further connected through the bptc4− ligands each other, giving rise to a 2D network. There is a Mn2O2 parallelogram-core in every {Mn}4 cluster, and to the best of our knowledge this is the first time observed. Complex 2 consists of the dinuclear manganese (II) unit, which is further linked by hydrogen bonds to form a 3D framework structure. Magnetic measurements show there is a weak anti-ferromagnetic interaction in complex 1. Moreover, the IR, element analysis, and thermal stability of the two complexes have been investigated systemically.

It has been found that there is a very complex and chaotic phenomena in the power system and other nonlinear system. Chaos is a very complex phenomenon caused by the interaction of the parameters in nonlinear systems, its appearance will accompany the non-periodic、seems to be without rules、sudden or paroxysmal mechanical and electrical oscillation of the system, which will cause widespread blackout and disintegration of the system when the oscillation becomes serious. Therefore, due to the wind power system is a typical large-scale complex non-linear system, so that chaotic phenomena will also occur under certain conditions and chaos will influence the stable operation of the wind power system, so the chaotic research are particularly important along with the fast development of grid-connected wind power technology.

Chaos theory is an important aspect of non-linear research, and has infiltrated a number of disciplines and engineering fields. With the increasing scale of power systems, the nonlinear characteristics are more and more obvious, under certain conditions there will even be chaotic behavior, appears as irregular electromechanical oscillations, constituting a threat to the system.[1-3]. So it becomes an urgent need to take effective control measures to curb or eliminate the chaotic oscillations in the non-linear power system. Chaos oscillation in the power system is harmful and should take measures to suppress and eliminate. There have been a lot of chaos control methods, and each has its own advantages and disadvantages and different application. This report mainly studies fuzzy control among its advantages and the features of the power system.

A novel tripeptide Schiff-base heterotrinuclear complex, [Co(H2O)4(CuL)2]·4H2O (1) (H3L = N-5-bromosalicylideneglycylglycylglycine) has been synthesized and characterized by elemental analyses, IR and electronic spectra. Single-crystal X-ray diffraction analysis showed that the molecular structure is made up of centrosymmetrical trinuclear units with the Co atom lying on an inversion center. Through Cu ··· O and Cu ··· Br weak interactions and hydrogen bonds, the 1D supramolecular chain structure is formed. The magnetic susceptibility data (2–300 K) revealed antiferromagnetic interactions between copper(II) ions and the central metal cobalt(II) ions. The magnetic susceptibility data were quantitatively analyzed using the theoretical expressions deduced from the spin Hamiltonian for a symmetrical three-spin system to give the coupling J CuCo = −2.26 cm−1.

Silk fibroin (SF) microspheres were produced by salting out SF solution via the addition of potassium phosphate buffer solution (K2HPO4-KH2PO4). The morphology, size and polydispersity of SF microspheres were adjusted by changing the molecular weight (MW) distribution and concentration of SF, as well as the ionic strength and pH of the buffer solution. Changing the conditions under which the SF fiber dissolved in the Lithium Boride (LiBr) solution resulted in altering the MW distribution of SF solution. Under optimal salting-out conditions (ionic strength>0.7 M and pH>7) and using a smaller and narrower SF MW distribution, SF microspheres with smoother shapes and more uniform sizes were produced. Meanwhile, the size and polydispersity of the microspheres increased when the SF concentration was increased from 0.25 mg/mL to 20 mg/mL. The improved SF microspheres, obtained by altering the distribution of molecular weight, have potential in drug and gene delivery applications.

In the title compound, [Mn(H2O)6][Cu(C12H11N2O4)]2·12H2O, the Cu atom has a square-planar coordination with two N and two O atoms of the tetradentate Schiff base ligand. The centrosymmetric cation [Mn(H2O)6]2+ and anion [CuL]− (L is a Schiff base derived from alanylglycine and salicylaldehyde) occupy a stacking structure within well separated columns along the c axis.

Using an estrogen-inducible expression XVE (LexA-VP16-Estragon Receptor) system, we have generated approximately 40 000 independent T-DNA insertion lines of Arabidopsis thaliana. Segregation analyses of about 18000 lines indicated that 51.6% of them contain single T-DNA insertions and that the average insertion number is 1.38 copies per line. Mutants displaying a variety of morphological alterations were identified, including those that affect development of roots,hypocotyls, leaves, floral organs and seeds as well as the flowering time.

RAV1 is a novel DNA-binding protein with two distinct DNA-binding domains unique in higher plants, but its role in plant growth and development remains unknown. Using cDNA array, we found that transcription of RAV1 is down-regulated by epibrassinolide (epiBL) in Arabidopsis suspension cells. RNA gel blot analysis revealed that epiBL-regulated RAV1 transcription involves neither protein phosphorylation/dephosphorylation nor newly synthesized protein, and does not require the functional BRI1, suggesting that this regulation might be through a new BR signaling pathway. Overexpressing RAV1 in Arabidopsis results in a retardation of lateral root and rosette leaf development, and the underexpression causes an earlier flowering phenotype, implying that RAV1 may function as a negative regulatory component of growth and development.

Glutathione S-transterased (GSTs) are a highly divergent gene family. They play important roles not only in many stress responses, but also in plant growth and development. To understand whether the GST can protect plant from the damage of ultra-violet (UV) radiation, a UV inducible GST gene was isolated from an Arabidopsis cDNA library. The plant expression vector containing the GST cDNA was constructed and transferred into Arabidopsis thaliana plants by the Agrobacterium-mediated vacuum method. Molecular genetic analyses showed that the overexpression of the UV inducible GST could increase the tolerance of the transgenic plants to UV radiation.

Starch nanoparticles (SNP) were prepared by traditional sulfuric acid hydrolysis using corn starch as raw material, and SNP was oxidized by potassium bromate (KBrO3) to prepare oxidized starch nanoparticles (OSNP). The structure and properties of SNP and OSNP were characterized by Fourier transform infrared spectrometer, X-ray powder diffractometer, laser particle size analyzer and dispersion test experiment. The results showed that native starch was transformed from micro grade (6 - 10 μm) to nano grade with the formation of SNP (240 nm) and OSNP (180 nm). Compared with native starch, OSNP has good dispersibility due to its small particle size and negative charges, which will expand its application areas by combing the advantages of oxidized starches and nanoparticles.