Copper-Catalyzed Dynamic Kinetic Asymmetric Arylation of Secondary Phosphine-Boranes for the Synthesis of P(III)-Stereogenic Centers.

Transition-metal-catalyzed asymmetric C-P(III) bond formation is a direct method for the construction of P(III)-stereogenic centers; however, achieving high enantioselectivity remains a challenge. Herein, an unprecedented Cu-catalyzed dynamic kinetic resolution of secondary phosphine-boranes was successfully developed. This asymmetric C-P(BH) coupling reaction provided the direct and highly enantioselective synthesis of P(III)-stereogenic centers, enabling the formation of chiral medium-sized benzophosphine-boranes (7-10-membered cycles).

Effects of different ratios of water and glycerol on the physicochemical properties of starch-based straws.

This study aimed to assess the effects of different ratios of water and glycerol on the physicochemical properties of starch-based straws (SBS) and explore their plasticising mechanism. X-ray diffraction analysis revealed that the V-type complex formation was influenced by adjusting the ratio of glycerol and water. The extruded samples exhibited lower water content (4.

Influence of the rigidity of the backbone and arms on the dynamical and conformational properties of the comb polymer in shear flow.

The dynamical and conformational properties of the comb polymer with various rigidities of the backbone and arms in steady shear flow are studied by using a hybrid mesoscale simulation approach that combines multiparticle collision dynamics with standard molecular dynamics. First, during the process of the comb polymer undergoing periodic tumbling motion, we find that the rigidity of the arms always promotes the tumbling motion of the comb polymer, but the rigidity of the backbone shifts from hindering to promoting it with increasing the rigidity of the arms. In addition, the comb polymer transitions from vorticity tumbling to gradient tumbling with the increase in shear rate.

Portable hydroxyl-functionalized coal gangue-based cordierite porous ceramics sheets for effective adsorption of fluorine-containing wastewater.

Monolithic adsorbent removal of fluoride from water is considered an effective and non-secondary pollution method. Here, a portable hydroxyl-functionalized coal gangue-based cordierite porous ceramic sheet (ACGC-Fe) is prepared by using coal gangue solid waste with a specific silicon-aluminum-rich composition ratio and a small amount of magnesium oxide as a raw material through powder compression molding and mild chemical modification. The prepared ACGC-Fe can be used to treat fluorine-containing wastewater and the maximum adsorption of fluorine can reach 18.

Aquaporin ZmTIP2;3 Promotes Drought Resistance of Maize through Symbiosis with Arbuscular Mycorrhizal Fungi.

Arbuscular mycorrhizal fungi symbiosis plays important roles in enhancing plant tolerance to biotic and abiotic stresses. Aquaporins have also been linked to improved drought tolerance in plants and the regulation of water transport. However, the mechanisms that underlie this association remain to be further explored.

Influence of friction on the packing efficiency and short-to-intermediate range structure of hard-sphere systems.

Using particle-resolved computer simulations, we investigate the effect of friction on the packing structure of hard-sphere mixtures with two kinds of particles under external compression. We first show that increasing friction between the particles results in a more disordered and less efficient packing of the local structure on the nearest neighbor scale. It is also found that standard two-point correlation functions, i.

Effect of modification by maltogenic amylase and branching enzyme on the structural and physicochemical properties of sweet potato starch.

Sweet potato starch (SPSt) was treated sequentially with the combination of maltogenic amylase (MA) and branching enzyme (BE) (MA → BE) or BE and MA (BE→MA) to modify its structural and physicochemical properties. Following the MA → BE and BE→MA modifications, the degree of branching was increased from 12.02 % to 44.

Single-polymer dynamics of starch-like branched ring polymers in steady shear flow.

The stretching dynamics and dynamical behaviors of individual branched ring polymer (BRP), a coarse-grained model for some types of the starch, in steady shear flow are studied by using a hybrid mesoscale simulation approach that combines multiparticle collision dynamics with standard molecular dynamics. By analyzing the stretched configuration of BRPs, we find the polymer size increases nonmonotonically with increasing branch length. Meanwhile, the decrease of the alignment angle of the stretched configuration of BRPs follows a universal power law during the first downward phase as the shear rate increases.

Correlation between chain structures of corn starch and properties of its film prepared at different degrees of disorganization.

This study investigated the relationship between the chain structure of corn starch and the properties of corn starch-based films formed with starch pastes with different degrees of disorganization (70, 80, and 90 °C). The degree of gelatinization, chain length distribution, amylose content, and molecular weight of the corn starch were determined by the water absorption index, ion chromatography, spectrophotometry, and gel chromatography, respectively. The thickness, surface roughness, solubility, water content, water vapor permeability, mechanical properties, and maximum thermal degradation rate of corn starch-based films formed with starch pastes with different degrees of disorganization were evaluated.

Chiral three-dimensional supramolecular assemblies: colloidal onions, cubosomes, and hexosomes.

Amphiphilic molecules can self-assemble in solution into a variety of supramolecular assemblies, ranging from simple micelles, ribbons, and tubes to complex cubosomes with bicontinuous cubic nanostructures. It is well known that the self-assembly of chiral building blocks into one-dimensional (1D) twisted fibers, helical ribbons, and tubes enables chiral transfer from the molecular scale to super-assemblies. In this study, we investigate the chirality of three-dimensional (3D) supramolecular assemblies, such as colloidal onions, cubosomes, and hexosomes, formed from the same chiral heteroclusters.

Dynamical and Structural Properties of Comb Long-Chain Branched Polymer in Shear Flow.

Using hybrid multi-particle collision dynamics (MPCD) and a molecular dynamics (MD) method, we investigate the effect of arms and shear flow on dynamical and structural properties of the comb long-chain branched (LCB) polymer with dense arms. Firstly, we analyze dynamical properties of the LCB polymer by tracking the temporal changes on the end-to-end distance of both backbones and arms as well as the orientations of the backbone in the flow-gradient plane. Simultaneously, the rotation and tumbling behaviors with stable frequencies are observed.

Efficient Broadband Near-Infrared Emission from Lead-Free Halide Double Perovskite Single Crystal.

Ultra-broadband near-infrared (NIR) luminescent materials are the most important component of NIR light-emitting devices (LED) and are crucial for their performance in sensing applications. A major challenge is to design novel NIR luminescent materials to replace the traditional Cr -doped systems. We report an all-inorganic bismuth halide perovskite Cs AgBiCl single crystal that achieves efficient broadband NIR emission by introducing Na ions.

Facile Microwave Synthesis of a Narrow-Band Green-Emitting Phosphor CsMnBr and the Effect of Anion Substitution on Its Luminescence Properties.

A bright blue light excitable and narrow-band green-emitting phosphor CsMnBr has been synthesized by a facile microwave radiation method within 2 min. The influence of the matrix on its steady-state and transient-state luminescence properties is investigated by partial substitution of Br ions by Cl ions. The incorporation of Cl ions in CsMn(BrCl) resulted in almost no change in the emission maxima of Mn, which is attributed to the synergistic effect of reduced covalency and increased crystal field strength caused by the replacement of Br ions by Cl ions.

A Trefoil Knot Polymer Chain Translocates through a Funnel-like Channel: A Multi-Particle Collision Dynamics Study.

With combining multi-particle collision dynamics (MPCD) for the solvent and molecular dynamics (MD) for the polymer chains, we have studied the conformation and untying behaviors of a trefoil knot polymer chain translocated through a confined funnel-like channel. For the trefoil knot chain, we found that the untying knot behavior mostly happens during the translocation process, and the translocation behavior of linear chains is also simulated as a comparison. Some characteristics of the trefoil knot chain during translocation process, such as average gyration radius and the average end-to-end distances are discussed, and we statistic the scale relations of the translocation time versus the chain length, and that of the chain rigidity.

High antibacterial and barrier properties of natural rubber comprising of silver-loaded graphene oxide.

The antibacterial and barrier properties of natural rubber used as gloves are very important for the safety of medical staffs. In this research, the silver (Ag) particles were loaded on the surface of graphene oxide (GO) first modified by polydopamine (PDA). Then, the complex particles (Ag-PDA-GO) were introduced into the natural rubber (NR) latex, and the Ag-PDA-GO/NR film composites were obtained by the dipping method.

Na-functionalized carbon dots with aggregation-induced and enhanced cyan emission.

A new type of carbon dots that emit blue emission in aqueous state while cyan emission in solid state was synthesized by a simple hydrothermal method. The photoluminescence quantum yield of the carbon dots in aqueous state and solid state is 7.6% and 29.

Preparation and Chemical Protective Clothing Application of PVDF Based Sodium Sulfonate Membrane.

Chemical protective clothing (CPC) is major equipment to protect human skin from hazardous chemical warfare agents (CWAs), especially nerve agents and blister agents. CPC performance is mainly dominated by the chemical protective material, which needs to meet various requirements, such as mechanical robustness, protective properties, physiological comfort, cost-effectiveness, and dimensional stability. In this study, polyvinylidene fluoride (PVDF) based sodium sulfonate membranes with different ion exchange capacities (IECs) are prepared simply from low-cost materials.

Highly Green Emissive Nitrogen-Doped Carbon Dots with Excellent Thermal Stability for Bioimaging and Solid-State LED.

In this study, nitrogen-doped green emissive carbon dots (N-doped CDs) are synthesized via a convenient one-step solid state reaction method. The N-doped CDs show excitation-dependent fluorescence behavior with a maximum emission of 540 nm. Upon the optimum excitation at 400 nm, the quantum yield (QY) of the green emissive CDs is determined to be 13.

Solid-State Carbon Dots with Efficient Cyan Emission towards White Light-Emitting Diodes.

Efficient cyan-emitting solid carbon dots (CDs) were synthesized via a one-pot hydrothermal method. The obtained solid CDs show a broad absorption from 270-460 nm with a maximum around 400 nm, and emit intense cyan light around 500 nm with an internal photoluminescence quantum efficiency of 34.1 % under 400 nm excitation.

Synthesis of boronate-decorated polyethyleneimine-grafted porous layer open tubular capillaries for enrichment of polyphenols in fruit juices.

A combination between modification with porous layer and grafting of polyethyleneimine (PEI) on the inner face of capillary was for the first time developed for boronate affinity in-tube solid-phase microextraction (SPME) material to enhance the extraction capacity for cis-diol-containing polyphenols. The successful synthesis of boronate-decorated polyethyleneimine-grafted porous layer open tubular (BPPLOT) capillary was confirmed by scanning electron micrograph, Fourier transform-infrared spectra and absorption experiments. The porous layer, PEI and boronate affinity provided high specific surface area, more binding sites for boronate groups and specific selectivity of BPPLOT capillary, respectively.

Applicability Evaluation of Bright Green-Emitting Carbon Dots in the Solid State for White Light-Emitting Diodes.

Self-quenching-resistant and bright green-emitting carbon dots (CDs) in the solid state were synthesized via a facile hydrothermal method. Their structure, optical properties together with their thermal and photostabilities, as well as their applicability in white LEDs were investigated. The obtained CDs have nearly spherical shape with a size around 4-5 nm.

Ni-Al Bimetallic Catalyzed Enantioselective Cycloaddition of Cyclopropyl Carboxamide with Alkyne.

A Ni-Al bimetallic catalyzed enantioselective cycloaddition reaction of cyclopropyl carboxamides with alkynes has been developed. A series of cyclopentenyl carboxamides were obtained in up to 99% yield and 94% ee. The bifunctional-ligand-enabled bimetallic catalysis proved to be an efficient strategy for the C-C bond cleavage of unreactive cyclopropanes.

High Quantum Yield Green-Emitting Carbon Dots for Fe(ІІІ) Detection, Biocompatible Fluorescent Ink and Cellular Imaging.

In the present work, we reported the luminescence of a green-emitting carbon dots (CDs) synthesized via solid state reaction method using diammonium hydrogen citrate and urea as a starting materials. The obtained green-emitting CDs shows strong absorption in the 350-450 nm region and gives intense green emission (λ = 537 nm) with quantum yield as high as 46.4% under 420 nm excitation.

Near-infrared persistent luminescence of Yb in perovskite phosphor.

Here we report the observation of near-infrared persistent luminescence (NIR PersL) of Yb in perovskite CaTiO. Sensitized by the Bi codopants, it exhibits intense NIR PersL of Yb at about 1000 nm. In addition, this phosphor can be excited by the near ultraviolet and even visible light, and the PersL signals can be recorded for more than 80 h.