Simultaneous removal of PAHs and heavy metals from soil by combining electrokinetic-assisted delivery of persulfate and ultrasound activation.

Herein, we proposed and demonstrated a novel approach of combining electrokinetics (EK)-assisted delivery of persulfate (PS) and ultrasound-induced thermal activation of PS and release of heavy metals, to synchronously remove organic pollutants and heavy metals from soil. Results showed that in tested soil, the mass transfer efficiency of PS induced by electromigration was approximately 3.36 times that by electroosmotic flow and 1416 times that by diffusion.

The conservation of allelic DNA methylation and its relationship with imprinting in maize.

Genomic imprinting refers to allele-specific expression of genes depending on parental origin, and it is regulated by epigenetic modifications. Intraspecific allelic variation for imprinting has been detected; however, the intraspecific genome-wide allelic epigenetic variation in maize and its correlation with imprinting variants remain unclear. Here, three reciprocal hybrids were generated by crossing Zea mays inbred lines CAU5, B73, and Mo17 in order to examine the intraspecific conservation of the imprinted genes in the kernel.

Characterization of Genes That Exhibit Genotype-Dependent Allele-Specific Expression and Its Implications for the Development of Maize Kernel.

Heterosis or hybrid vigor refers to the superior phenotypic traits of hybrids relative to their parental inbred lines. An imbalance between the expression levels of two parental alleles in the F1 hybrid has been suggested as a mechanism of heterosis. Here, based on genome-wide allele-specific expression analysis using RNA sequencing technology, 1689 genes exhibiting genotype-dependent allele-specific expression (genotype-dependent ASEGs) were identified in the embryos, and 1390 genotype-dependent ASEGs in the endosperm, of three maize F1 hybrids.

Conservation Study of Imprinted Genes in Maize Triparental Heterozygotic Kernels.

Genomic imprinting is a classic epigenetic phenomenon related to the uniparental expression of genes. Imprinting variability exists in seeds and can contribute to observed parent-of-origin effects on seed development. Here, we conducted allelic expression of the embryo and endosperm from four crosses at 11 days after pollination (DAP).

Solvent-Driven Chirality Switching of a Pillar[4]arene[1]quinone Having a Chiral Amine-Substituted Quinone Subunit.

Several new chiral pillar[4]arene[1]quinone derivatives were synthesized by reacting pillar[4]arene[1]quinone (), containing four 1,4-diethoxybenzene units and one benzoquinone unit, with various chiral amines Michael addition. Due to the direct introduction of chiral substituents on the rim of pillar[n]arene and the close location of the chiral center to the rim of , the newly prepared compounds showed unique chiroptical properties without complicated chiral resolution processes, and unprecedented high anisotropy factor of up to -0.018 at the charge transfer absorption band was observed.

Pressure-driven, solvation-directed planar chirality switching of cyclophano-pillar[5]arenes (molecular universal joints).

Planar chiral cyclophanopillar[5]arenes with a fused oligo(oxyethylene) or polymethylene subring (s), existing as an equilibrium mixture of subring-included (in) and -excluded (out) conformers, respond to hydrostatic pressure to exhibit dynamic chiroptical property changes, leading to an unprecedented pressure-driven chirality inversion and the largest ever-reported leap of anisotropy () factor for the with a dodecamethylene subring. The pressure susceptivity of s, assessed by the change in per unit pressure, is a critical function of the size and nature of the subring incorporated and the solvent employed. Mechanistic elucidations reveal that the in-out equilibrium, as the origin of the 's chiroptical property changes, is on a delicate balance of the competitive inclusion of subrings solvent molecules as well as the solvation of the excluded subring.

Overtemperature-protection intelligent molecular chiroptical photoswitches.

Stimuli-responsive intelligent molecular machines/devices are of current research interest due to their potential application in minimized devices. Constructing molecular machines/devices capable of accomplishing complex missions is challenging, demanding coalescence of various functions into one molecule. Here we report the construction of intelligent molecular chiroptical photoswitches based on azobenzene-fused bicyclic pillar[n]arene derivatives, which we defined as molecular universal joints (MUJs).

Electrochemiluminescent Chiral Discrimination with a Pillar[5]arene Molecular Universal Joint-Coordinated Ruthenium Complex.

A bicyclic pillar[5]arene derivative fused with a bipyridine side ring, a so-called molecular universal joint (MUJ), was synthesized, and the pair of enantiomers was resolved by high-performance liquid chromatography enantioresolution. The electrochemiluminescent detection based on the ruthenium complex of the enantiopure MUJ showed excellent chiral discrimination toward certain amino acids.

Supramolecular spectral/visual detection of urinary polyamines through synergetic/competitive complexation with γ-CD and CB[7].

A supramolecular strategy for detecting the concentration of polyamines has been established through competitive/synergetic complexation among polyamines, CB[7], γ-CD, and pyrene derivatives, which allows for convenient, rapid, and high throughput spectral/visual detection of the concentration of urinary polyamines based on the switching on/off of the pyrene excimer fluorescence.

Guest-Binding-Induced Interhetero Hosts Charge Transfer Crystallization: Selective Coloration of Commonly Used Organic Solvents.

Unprecedented interheteromacrocyclic hosts charge transfer (CT) crystals were generated by cooling organic solutions containing -dimethoxybenzene-constituted pillar[5]arene () and -benzoquinone-constituted pillar[5]quinone (). Despite the weak CT interaction known between -dimethoxybenzene and -benzoquinone and the lack of formation of CT complexes between and in the solution phase, CT cocrystals between and were formed with solvent molecules included into the hosts' cavities. Such a cocrystallization arises from an elegant synergy between the CT interaction and solvent-binding-promoted crystallization.

pH-Controlled Chirality Inversion in Enantiodifferentiating Photocyclodimerization of 2-Antharacenecarboxylic Acid Mediated by γ-Cyclodextrin Derivatives.

Several γ-cyclodextrin (γ-CDx) derivatives were used as chiral hosts for the photocyclodimerization of 2-anthracenecarboxylic acid (AC). The effect of pH on photoreactivity and stereochemical outcome of photoproducts was investigated. Upon changing the solution pH, the stereochemical outcome of HH cyclodimer was inverted from 25.

A Quinoline-Appended Cyclodextrin Derivative as a Highly Selective Receptor and Colorimetric Probe for Nucleotides.

The design and development of specific recognition and sensing systems for biologically important anionic species has received growing attention in recent years, as they play significant roles in biology, pharmacy, and environmental sciences. Herein, a new supramolecular sensing probe L1 was developed for highly selective differentiation of nucleotides. L1 displayed extremely marked absorption and emission differentiation upon binding with nucleotide homologs of AMP, ADP, and ATP, due to the divergent spatial orientations of guests upon binding, which allowed for a naked-eye colorimetric differentiation for nucleotides.

Fulleropillar[4]arene: The Synthesis and Complexation Properties.

A multihydroquinone ether dialdehyde derivative was incidentally obtained through an unexpected ring opening of pillar[4]arene[1]quinone . And the Prato reaction of with [60]fullerene led to [60]fullerene bisadducts, from which cyclic regioisomer was isolated and characterized. The fulleropillar[4]arene showed a larger cavity and can accommodate a viologen derivative with a much stronger affinity than permethyl pillar[5]arene () and pillar[4]arene[1]quinone .

Effect of anolytic nitrite concentration on electricity generation and electron transfer in a dual-chamber microbial fuel cell.

This study reports the effect of anolytic nitrite concentration on electricity generation and electron transfer in microbial fuel cells (MFCs). Anolytic nitrite enhanced the electricity generation capability of the MFCs at relatively low concentrations (< 60 mg·L) but inhibited the activity of anodic electrogenic bacteria at high concentrations. In the anode chamber of the MFC, nitrite was converted to nitrate-releasing electrons before being quickly removed through denitrification.

Precise Manipulation of Temperature-Driven Chirality Switching of Molecular Universal Joints through Solvent Mixing.

Three chiral bicyclic pillar[5]arene derivatives termed as molecular universal joints (MUJs), were synthesized and separated enantiomerically. These MUJs showed temperature-driven chirality switching in certain solvents. Herein, it is demonstrated that temperature-driven chirality switching could also be realized by mixing two miscible organic solvents, in each of which chirality inversion is not accomplishable.

Temperature-Driven Planar Chirality Switching of a Pillar[5]arene-Based Molecular Universal Joint.

The study of an enantiopure bicyclic pillar[5]arene-based molecular universal joint (MUJ) by single-crystal X-ray diffraction allowed for the first time the unequivocal assignment of the absolute configuration of a planar chiral pillar[5]arene by circular dichroism spectroscopy. Crucially, the absolute configuration of the MUJ was switched reversibly by temperature, with an accompanying sign inversion of the anisotropy factor that varied by as much as 0.03, which is the largest value ever reported.

Ammonia-driven chirality inversion and enhancement in enantiodifferentiating photocyclodimerization of 2-anthracenecarboxylate mediated by diguanidino-γ-cyclodextrin.

In the supramolecular photocyclodimerization of 2-anthracenecarboxylate mediated by 6(A),6(D)-diguanidino-γ-cyclodextrin (CD), the chiral sense and enantiomeric excess of the photoproduct were dynamic functions of temperature and cosolvent to afford the (M)-anti head-to-head cyclodimer in 64% ee in aqueous methanol at -70 °C but the antipodal (P)-isomer in 86% ee in aqueous ammonia at -85 °C, while the corresponding diamino-γ-CD host did not show such unusual photochirogenic behaviors. The ee landscape was very steep against the temperature and sign-inverted against the ammonia content to reveal the opposite temperature dependence at low and high ammonia contents, for which an altered solvent structure and/or guanidinium-carboxylate interaction mode would be responsible.