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Developing bioseparation media with both high strength and high surface area capable of efficiently separating proteins is a significant challenge. In this study, nanofibrous membranes (NFMs) with mechanical strength up to 10.8 MPa were successfully prepared by using a simple hot pressing and cross-linking process. Subsequently, mixed-mode chromatography (MMC) with both electrostatic and hydrophobic interactions was achieved by introducing glutaric anhydride (GA) onto the surface of the regenerated cellulose (RC) nanofibers. The separation of lysozyme using MMC membranes showed that the static adsorption of lysozyme (1 mg/mL) on RC-g-GA NFM reached 254 mg/g. The dynamic binding capacity of lysozyme in the flow-through mode at 10% breakthrough was 72.8 mg/g. Meanwhile, additionally, the RC-g-GA NFM could saturate lysozyme (3 mg/mL) adsorption up to 336 mg/g after 6 h of adsorption time. Moreover, the membrane could isolate lysozyme with 85% purity from a mixed solution of lysozyme and γ-globulin. This work demonstrates that RC-g-GA NFM has an efficient lysozyme isolation capability and potential for scale-up applications. [ABSTRACT FROM AUTHOR]

A low-shrinkage and viscosity-reducing polycarboxylate superplasticizer was synthesized with maleic anhydride (MAH), diethylene glycol monobutyl ether, and methoxypoly (ethylene glycol) methacrylate (MPEGnMA). The surface tension, early shrinkage, cement paste performance, and application performance of concrete made with the synthesized water-reducing admixture were tested. A series of experiments were conducted to determine the optimal range of plastic viscosity coefficients for producing high-quality, fair-faced concrete with minimal surface defects. These experiments utilized both the synthesized water-reducing admixture alone and in combination with other water-reducing agents. The results showed that the synthesized water-reducing admixture had an ideal molecular structure, as confirmed by the GPC spectrum. When added to an aqueous solution, it reduced the surface tension from 72.47 mN/m to 30.56 mN/m. The 72 h shrinkage value of concrete was reduced by 20.6% compared with that of the conventional control group, effectively reducing shrinkage and adjusting the viscosity of the concrete mixture. Additionally, the influence of the plastic viscosity coefficient on the apparent voids in fair-faced concrete was investigated. This study revealed that when the plastic viscosity coefficient was between 5 and 10 Pa·s, the apparent void grade of the fair-faced concrete was simultaneously excellent and good. This water-reducing admixture helped prevent surface cracking and voids in fair-faced concrete, making it a suitable choice for producing high-quality fair-faced concrete surfaces. [ABSTRACT FROM AUTHOR]

The first laser–plasma interaction experiment using lasers of eight beams grouped into one octad has been conducted on the Shenguang Octopus facility. Although each beam intensity is below its individual threshold for stimulated Brillouin backscattering (SBS), collective behaviors are excited to enhance the octad SBS. In particular, when two-color/cone lasers with wavelength separation 0.3 nm are used, the backward SBS reflectivities show novel behavior in which beams of longer wavelength achieve higher SBS gain. This property of SBS can be attributed to the rotation of the wave vectors of common ion acoustic waves due to the competition of detunings between geometrical angle and wavelength separation. This mechanism is confirmed using massively parallel supercomputer simulations with the three-dimensional laser–plasma interaction code LAP3D. [ABSTRACT FROM AUTHOR]

Under solvothermal conditions, one new CdII coordination polymer [Cd(bbimc)(ata)]n (1)] based on carbazole ligand 3,6-bis(1H-benzo[d]imidazol-1-yl)-9-methyl-9H-carbazole (bbimc) and 2-aminoterephthalic acid ligand (H2ata) was synthesized. Single-crystal structural determination revealed that 1 takes a two-dimensional (2D) structure with an sql topology. In particular, 1 shows good thermal (413 °C) and excellent acid/base stability in aqueous solutions with pH values of 1–13. Furthermore, 1 could selectively detect Hg2+, Fe3+, and antibiotics (TC: tetracycline; CTC: chlortetracycline) in aqueous solutions with high selectivity and sensitivity through a turn-off effect, and the detection limits are 0.246 μM (Hg2+), 0.342 μM (Fe3+), 0.208 μM (TC), and 0.307 μM (CTC). Moreover, the detection mechanism analysis by experiment and theoretical calculation revealed that competitive absorption (CA) and photoinduced electron transfer (PET) are largely responsible for sensing Fe3+ and the two antibiotics (TC, CTC). However, the weak interaction between Hg2+ and –NH2 of the framework structure contributes to partial luminescence quenching. [ABSTRACT FROM AUTHOR]

The development of luminescent metal–organic frameworks for effective sensing and monitoring of environmental pollutants is of great significance for human health and environmental protection. In this work, a novel water-stable ZnII-based luminescent coordination polymer, namely {[Zn(BBDF)(ATP)]·2DMF·3H2O}n ((BBDF = 2,7-bis(1H-benzimidazol-1-yl)-9,9-dimethyl-9H-fluorene) and H2ATP = 2-aminoterephthalic acid), was designed and obtained using the mixed-ligand method. Structural analysis indicated that 1 presents a two-fold interpenetrated two-dimensional layer structure with one dimensional (1D) channels along the a axis. Intriguingly, the uncoordinated –NH2 group was danged onto the pore walls of 1. Remarkably, compound 1 shows good aqueous stability at different pH values of 3–13 and exhibits a fluorescence turn-off sensing behavior for Hg2+, Cr2O72−, CrO42−, and antibiotics (NFZ, NFT) in aqueous solution with high selectivity and sensitivity. The limits of detection (LOD) are 0.12 μM (Hg2+), 0.17 μM (Cr2O72−), 0.21 μM (CrO42−), 0.098 μM (NFZ), and 0.14 μM (NFT). The luminescence quenching mechanism analysis by experiment and theoretical calculation revealed that the competitive absorption and the photoinduced electron transfer process are largely responsible for the sensing of the two antibiotics, while the weak interaction contributes to the selective luminescence quenching for Hg2+. [ABSTRACT FROM AUTHOR]

Five new ZnII/CdII coordination polymers (CPs) based on a flexible bis(imidazole) ligand 9,10-bis((2-methyl-1H-imidazol-1-yl)methyl)anthracene (bmima) with three different aromatic carboxylic acid ligands have been synthesized under solvothermal conditions: {[Cd(bmima)0.5(atp)(H2O)]·DMF·0.5H2O} (CP 1), {[Zn(bmima)(atp)]·DMF} (CP 2), {[Cd(bmima)(bpdc)]·2DMF} (CP 3), and {[M(bmima)0.5(oda)]·DMF·H2O} (M = Zn for CP 4 and Cd for CP 5), (H2atp = 2-aminoterephthalic acid; H2bpdc = [1,1′-biphenyl]-4,4′-dicarboxylic acid and H2oda = 4,4′-oxydibenzoic acid). CP 1 displays a 3,4-connected TiSc topology 3D framework with vertex symbols of {42·6·102·12}{42·6}. CP 2 and CP 3 both feature 2D layer structures with a five-fold interpenetration framework for CP 3. CP 4 and CP 5 both show a 3D "pillar-layer" structure with pcu α-Po topology. The structural differences of the five CPs may be due to the diverse coordination modes of dicarboxylate ligands and the conformation of flexible N-donor ligands. Moreover, CP 1 and CP 3 are two good fluorescent sensors for the detection of Fe3+, Cr2O72− and TNP. The mechanism of the two sensors shows that the fluorescent sensing process toward Fe3+ and Cr2O72− is mainly attributed to the competitive absorption process, while both competitive absorption and the more efficient FRET mechanism for TNP, respectively, which indicates that CP 1 and CP 3 can serve as two fluorescence sensors to sensitively and selectively detect the presence of Fe3+ and Cr2O72− in water. [ABSTRACT FROM AUTHOR]

Cyano-bridged mixed-valence {Fe6} hexanuclear complexes {[Tp4-MeFeII(CN)3]2[FeIII(Tpa)]2[FeIII(OR)(Tpa)]2}·6ClO4·S (Tp4-Me = tri(4-methyl-pyrazol-1-yl)borate, Tpa = tris(2-pyridylmethyl)amine; R = –CH3, S = 8MeOH 1, R = –C2H5, S = 6EtOH 2) have been obtained by building the units of [Tp4-MeFe(CN)3]− and [Fe(Tpa)]2+ in methanol and ethanol, respectively. Complex 1 exhibited single-crystal-to-single-crystal (SCSC) transformation to give {[Tp4-MeFeII(CN)3]2[FeIII(Tpa)]2[FeIII(OH)(Tpa)]2}·6ClO4·8H2O (3) in water. Detailed analysis of the coordination environment of the FeIII centers on the square lattice and magnetic susceptibility measurements of all the complexes confirmed their Fe3+ spin-crossover (SCO) properties (T1/2 = 178 K, 1; 185 K, 2; 208 K, 3). [ABSTRACT FROM AUTHOR]