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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]

This paper investigated the effect of nano-calcium silicate hydrate (n-C-S-H) on the early compressive strength of mineral powder-cement systems under low-temperature curing conditions (5 °C). The hydration mechanism of n-C-S-H in the mineral powder-cement system at different dosages was analyzed by combining it with XRD, DSC-TG, MIP, and other techniques. The results show that n-C-S-H significantly enhances the early compressive strength of the mineral powder-cement system under low-temperature curing conditions, with optimal results observed at a dosage of 1.0% (mass fraction). The XRD, DSC-TG, and MIP tests reveal that n-C-S-H promotes the hydration of the mineral powder cement, accelerates the generation rate of hydration products, reduces the porosity of the hardened mineral powder-cement slurry, and improves the system's density. [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]

Microencapsulated phase change materials (MicroPCMs) with paraffin as core and melamine -urea -formaldehyde (MUF)as shell materials were synthesized by in situ polymerization method. The chemical structure, particle size distribution, thermal performance and micro -morphology of the microcapsules that used Graphene oxide, Sodium dodecyl sulfate, Span80 and Tween80 as emulsifier were investigated. The results indicated that melamine-urea-formaldehyde (MUF)shell is effectively encapsulated on the surface of the paraffin core material to form composite phase change materials of microcapsule structure. Emulsifier has an obvious effect on the particle size distribution of MicroPCMs. When GO were used as emulsifier, the particle size distribution of the MicroPCMs is in the range of 3~20µm, the MicroPCMs showed a regular sphere shape with a encapsulation ratio of 39.8%. As the thermal resistance effect of the MUF shell materials, the thermal decomposition temperature range of the paraffin core material and the thermal stability of microcapsules are improved. [ABSTRACT FROM AUTHOR]

The effects of magnetic vortex acceleration (MVA) are investigated with two-dimensional particle-in-cell (PIC) simulations by laser interaction with near-critical density (NCD) plasma inside a hollow conical plasma. Energetic and collimated proton beams can be accelerated by a longitudinal charge-separation field. Energetic protons with a peak energy of 220 MeV are produced in PIC simulations. Compared with a uniform NCD plasma, both the cutoff energy and collimation of proton beams are improved remarkably. Furthermore, the influence of different gap sizes of cone tip is taken into account. For optimizing magnetic vortex acceleration, the gap size of the cone tip is suggested to match the focal spot size of laser pulse. [ABSTRACT FROM AUTHOR]

Target normal sheath field acceleration via laser interaction with structured solid targets has been widely studied for its potential use in a wide range of applications. Here, a novel nanowire target with a corrugated front surface is proposed to improve the proton acceleration by a target normal sheath field. Two-dimensional particle-in-cell simulations demonstrated that with the existence of the corrugated surface, the cut-off energy of accelerated protons nearly doubles compared to the planar nanowire target. When interacting with the corrugated surface, the incident laser pulse is reflected multiple times, focused and reinforced in each cavity near the front surface, which leads to suppression of the reflectivity and an improvement in the absorption rate. Electrons are heated more efficiently and the sheath field at the target rear side is naturally enhanced. To further investigate the performance of this novel target, a series of simulations with various laser intensities and target sizes were also carried out. This simple target design may provide insights for experiments in the future and should arouse interest because of its wide application. [ABSTRACT FROM AUTHOR]

Effects of solid nanolayers embedded in a near-critical density plasma on the laser-driven collisionless shock acceleration are investigated by using two-dimensional particle-in-cell simulations. Due to the interaction of nanolayers and the incident laser, an additional number of hot electrons are generated and an inhomogeneous magnetic field is induced. As a result, the collisionless shock is reinforced within the nanolayer gaps compared to the target without the structured nanolayers. When the laser intensity is 9.8 × 10 19  W / cm 2 , the amplitude of the electrostatic field is increased by 30% and the shock velocity is increased from 0.079c to 0.091c, leading to an enhancement of the peak energy and the cutoff energy of accelerated protons, from 6.9 MeV to 9.1 MeV and 12.2 MeV to 20.0 MeV, respectively. Furthermore, the effects of the width of the nanolayer gaps are studied, by adjusting the gap width of nanolayers, and optimal nanolayer setups for collisionless shock acceleration can be acquired. [ABSTRACT FROM AUTHOR]

The effect of re-dispersible vinyl acetate/ethylene copolymer powder on the mechanical properties of cement-based grouting material was analyzed by studying the cement hydration degree and the cement stone pore structure using X-ray diffraction, differential scanning calorimetry-thermogravimetirc analysis and mercury intrusion porosimetry analysis. The results showed that when the re-dispersible vinyl acetate/ethylene poly powders are added into cement-based grouting materials, the compressive and flexural strength of the grouting material gradually decreases, and with the increase of its content, the strength decreases more obviously. When the content of powder is 5%, compared with the reference mortar, the compressive strength of 1 d, 3 d, 28 d was reduced by 27.3%, 26.6%, 20.5%, and the 1 d, 3 d and 28 d flexural strength was reduced by 28.1%, 17.6%, 10.4%, respectively. [ABSTRACT FROM AUTHOR]

The coupling evolutions of stimulated Raman scattering (SRS) and Raman rescattering (re-SRS) are investigated under the parameter conditions of relevance to the gas-filled hohlraum experiments at the National Ignition Facility by using the nonenveloped fluid code FLAME. It is found that re-SRS works as a frequency filter of the backscattered light of SRS in the gas region. The low frequency modes of scattered light originated from a higher density region would stimulate re-SRS and be heavily depleted by re-SRS near the region of their quarter critical density. The energy in daughter waves of re-SRS is deposited in the gas plasmas. The large amplitude of the daughter Langmuir wave of re-SRS would stimulate cascade Langmuir decay instabilities and induce obvious low frequency density modulations, which can further result in the inflation of high frequency modes of scattered light of SRS at densities lower than the growth region of re-SRS. [ABSTRACT FROM AUTHOR]

High-order harmonic generation provides an opportunity for generating intense extreme ultraviolet attosecond pulses, which is useful to explore the property of materials. Transmitted radiation emitted by an ultrathin target illuminated by intense lasers is a promising way to generate such pulses. We show that the preplasma density gradient has an important influence on the transmitted radiation. An optimal scale length exists to support ultrathin nanobunches to generate coherent synchrotron emission and thus enormously enhance the radiation. Particle in cell simulations suggest that the optimal scale length depends on the laser intensity. [ABSTRACT FROM AUTHOR]

A study was conducted to examine the threshold dependence in a multidomain twisted nematic liquid crystal display supporting four pixels per domain. One-modulus approximation was carried out by assuming similar values for the splay, twist and bend elastic constants. Euler-Lagrange equations were modified to reduce the system free energy. Results indicated that the threshold voltage can be enhanced by the ratio of the pixel size to the cell thickness.

Lignin, as the most abundant aromatic renewable biopolymer in nature, has long been regarded as waste and simply discarded from the pulp and paper industry. In recent years, with many breakthroughs in lignin chemistry, pretreatment, and processing techniques, a lot of the inherent bioactivities of lignin, including antioxidant activities, antimicrobial activities, biocompatibilities, optical properties, and metal‐ion chelating and redox activities, have been discovered and this has opened a new field not only for lignin‐based materials but also for biomaterials. In this Review, the biological activities of lignin and drug/gene delivery and bioimaging applications of various types of lignin‐based material are summarized. In addition, the challenges and limitations of lignin‐based materials encountered during the development of biomedical applications are also discussed. [ABSTRACT FROM AUTHOR]

Bright extreme ultraviolet (XUV) sources with elliptical polarization are powerful tools for investigating the electronic and magnetic properties of materials. Here we show that in the regime of relativistic electrons spring, it is possible to generate a source of elliptically polarized attosecond XUV pulses by a circularly polarized laser pulse interacting with near-critical density plasmas. Particle-in-cell simulations indicate that compared with a conventional overdense plasma regime, the attosecond pulse intensity may be increased by up to one order of magnitude in a near-critical density plasma system. [ABSTRACT FROM AUTHOR]

In order to study the laser plasma instabilities (LPIs) in the context of some novel six-side laser-driven indirect designs like the six-cylinder-port hohlraum and the three-axis cylindrical hohlraum, where the laser beams inject in hohlraum with a large angle. LPI experiments in cylindrical hohlraum with only outer beams were designed and performed based on the current laser arrangement condition of SGIII laser facility for the first time. Stimulated Brillouin backscatter (SBS) was found to be the dominant instability with high instantaneous reflectivity in experiments. A typical feature was obtained in the time-resolved spectra of SBS, which maintained similar for different laser intensities of the interaction beam. The experimental data are analyzed by the hydrodynamic simulations combined with HLIP code, which is based on the ray-tracing model. By analysis of experimental data, it is argued that the mixture of gas and Au in the region of their interface is important to SBS, which indicates the need for the mixture model between the filled gas and the high Z plasma from hohlraum wall in the hydrodynamic simulations. Nonlinear saturation of SBS as well as the smoothed beam are also discussed here. Our effective considerations of the ions pervasion effect and the smoothed beam provide utilitarian ways for improvement of the current ray-tracing method. [ABSTRACT FROM AUTHOR]

Streptococcus zooepidemicus is an important opportunistic pathogen of several species including humans. This organism is also well-known as the main producing strain in industrial production of hyaluronic acid (HA), which is the component of its capsule polysaccharide. How its virulence and capsule polysaccharide production is regulated remains poorly understood. Intercellular chemical signaling among bacteria provides communities of microbes the opportunity to coordinate gene expression to facilitate group behavior, such as pathogenicity, capsule polysaccharide production, etc. Yet no conserved cell-to-cell signaling system has been elucidated in S. zooepidemicus. Encoded within the genome of S. zooepidemicus is one Rgg regulator encoding gene (rgg) with low similarity to both rgg2 and rgg3 from Streptococcus pyogenes. A small ORF (named as shp) encoding a novel short hydrophobic peptide (SHP) was found in the vicinity of rgg. We found that the active form of pheromone is short and hydrophobic (LLLLKLA), corresponding to the C terminal 7 amino acids of the pre-peptide Shp, which shows divergent sequence to all peptide pheromones reported in streptococci. In response to active SHP, Rgg functions as a transcriptional activator to induce the expression of shp , forming a positive feedback circuit. Bacteria social behaviors, such as capsule polysaccharide production and biofilm formation, were significantly affected when the rgg - shp pathway was inactivated. These data provide the first demonstration that Rgg/Shp signaling pathway comprises an active quorum sensing system in S. zooepidemicus. [ABSTRACT FROM AUTHOR]

We reported the synthesis of tris(pyridyl)phosphine selenide (TppSe) and tris(4-methylpyridin-2-yl)phosphine selenide (MeTppSe), which were prepared by a simple and straightforward one-pot method with red phosphorus in a KOH/DMSO suspension, and treatment of resulted phosphines with selenium in hot toluene. These compounds were characterized by mass spectroscopy, 1H, 13C and 31P NMR spectroscopies and the structure of MeTppSe was characterised by a single-crystal X-ray diffraction. Furthermore, The reactions of selenides with Fe(ClO4)2·6H2O afforded two new iron(II) mononuclear metal complexes [Fe(TppSe)2][ClO4]2·3DMF (1) and [Fe(MeTppSe)2][ClO4]2·2DMF (2). Detailed structural analyses and magnetic susceptibility measurements confirm no spin transition from low-spin to the high-spin state between 2 and 300 K in two iron(II) complexes. [ABSTRACT FROM AUTHOR]

The reactions of tricyanometallate precursors, (Ph3PMe)[(Tp4-Me)Fe(CN)3·0.5CH3CN] (1) (Tp4-Me = tri(4-methyl-pyrazol-1-yl)borate) and (NBu4)[(MeTp)Fe(CN)3] (MeTp = methyltris(pyrazolyl)borate) with the presence of the tetradentate tpa ligand (tpa = tris(2-pyridylmethyl)amine) and Fe(ClO4)2·6H2O afford two new cyano-bridged mixed-valence {FeIII2FeII2} molecular squares: [(Tp4-Me)FeIII(CN)3]2[FeII(tpa)]2·2ClO4·H2O (2·H2O) and [(MeTp)FeIII(CN)3]2[FeII(tpa)]2·2ClO4·CH3OH (3·CH3OH). Solvent-exchange compounds of 3·CH3OH, [(MeTp)FeIII(CN)3]2[FeII(tpa)]2·2ClO4·2H2O (3·2H2O), and their solvent-free form (2 and 3) are also obtained, respectively. The spin crossover (SCO) properties of all compounds are confirmed by detailed structural analyses of the coordination environments of the FeII centres and magnetic susceptibility measurements. All compounds exhibit SCO behaviour near room temperature (T1/2 = 320 K for 2·H2O; 302 K for 2; 292 K for 3·CH3OH; 306 K for 3·2H2O and 290 K for 3) and reversible single-crystal to single-crystal (SC–SC) transformations induced by guest desorption and resorption or solvent exchange. The transition temperature close to room temperature can be tuned by the dehydration and re-hydration processes. The structure–property analysis discloses that the distorted {Fe4(μ-CN)4} core and deviations of bent 〈Fe−N≡C angles play a key role in tuning the transition temperature of these similar mixed-valence {FeIII2FeII2} complexes. [ABSTRACT FROM AUTHOR]

Abstract: Escherichia coli has proved to be a successful host for the expression of many heterologous proteins, and much efforts have been made toward improving recombinant protein expression including the usage of strong promoters and co-expression with chaperones. But little attention was paid on the relation between expression level and function of the target protein. Glycerophosphate oxidase (GPO) is a protein with FAD cofactor (without free cysteine and disulfide bonds).It was observed that the specific activity of GPO dramatically decreased with the increase of inducer IPTG. In addition, the stability of it decreased correspondingly. The structural difference of samples expressed under varying IPTG was investigated using size-exclusion and reverse-phase high performance liquid chromatography, together with CD spectrum. It was found that the conformation of peptide and organization of subunits were not affected. The loss of specific activity and stability were correlated to incomplete attachment of FAD onto GPO. These results revealed that synthesis speed should be controlled either by reduction of IPTG amount or using weak promoters in the production of GPO. [ABSTRACT FROM AUTHOR]