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Organoseleniums exhibit a diverse set of biological activities that are pivotal for drug discovery and are widely explored in synthetic chemistry and material science. While many transformations have been developed for non-enantioselective C–Se bond formations, the catalyst-controlled stereoselective preparation of chiral organoseleniums continues to be of considerable challenge. In particular, there are limited studies on the enantioselective seleno-Michael addition reactions to access chiral selenium functional molecules. Here, we disclose a carbene-catalyzed highly enantioselective nucleophilic C–Se bond construction through formal [3 + 3] annulations between selenocarboxamides and bromoenals, affording seleno-thiazinone products with good yields and excellent enantioselectivities. The choice of a weak inorganic base was pivotal to suppressing the unproductive racemization and decomposition of the selenium products. Notably, the catalytically generated chiral selenium-containing heterocyclic products feature remarkable antimicrobial activities that could serve as promising lead scaffolds for further agrochemical development. [ABSTRACT FROM AUTHOR]

Macrolactones exhibit distinct conformational and configurational properties and are widely found in natural products, medicines, and agrochemicals. Up to now, the major effort for macrolactonization is directed toward identifying suitable carboxylic acid/alcohol coupling reagents to address the challenges associated with macrocyclization, wherein the stereochemistry of products is usually controlled by the substrate's inherent chirality. It remains largely unexplored in using catalysts to govern both macrolactone formation and stereochemical control. Here, we disclose a non-enzymatic organocatalytic approach to construct macrolactones bearing chiral planes from achiral substrates. Our strategy utilizes N-heterocyclic carbene (NHC) as a potent acylation catalyst that simultaneously mediates the macrocyclization and controls planar chirality during the catalytic process. Macrolactones varying in ring sizes from sixteen to twenty members are obtained with good-to-excellent yields and enantiomeric ratios. Our study shall open new avenues in accessing macrolactones with various stereogenic elements and ring structures by using readily available small-molecule catalysts. Macrolactones exhibit distinct conformational and configurational properties and are widely found in natural products but catalysts to govern both macrolactone formation and stereochemical control remain largely unexplored. Here, the authors disclose an N-heterocyclic carbene (NHC)-catalyzed enantioselective synthesis of chiral macrolactones varying in ring size from sixteen to twenty members that feature distinct configurationally stable planar stereogenicity. [ABSTRACT FROM AUTHOR]

Highlights: The synergistic "anchor-capture" mechanism of polar groups on Zn stripping/plating process is firstly proposed. The amino group firmly anchors on Zn surface and the carboxyl group strongly captures Zn2+, constructing a robust anode–electrolyte interface and inducing uniform Zn deposition. The ultra-stable cycle lifespan of Zn–Zn symmetric cell (over 2800 h) and high utilization rate of Zn anode (the depth of discharge up to 68% for 200 h) are achieved under the proposal of synergistic "anchor-capture." While the rechargeable aqueous zinc-ion batteries (AZIBs) have been recognized as one of the most viable batteries for scale-up application, the instability on Zn anode–electrolyte interface bottleneck the further development dramatically. Herein, we utilize the amino acid glycine (Gly) as an electrolyte additive to stabilize the Zn anode–electrolyte interface. The unique interfacial chemistry is facilitated by the synergistic "anchor-capture" effect of polar groups in Gly molecule, manifested by simultaneously coupling the amino to anchor on the surface of Zn anode and the carboxyl to capture Zn2+ in the local region. As such, this robust anode–electrolyte interface inhibits the disordered migration of Zn2+, and effectively suppresses both side reactions and dendrite growth. The reversibility of Zn anode achieves a significant improvement with an average Coulombic efficiency of 99.22% at 1 mA cm−2 and 0.5 mAh cm−2 over 500 cycles. Even at a high Zn utilization rate (depth of discharge, DODZn) of 68%, a steady cycle life up to 200 h is obtained for ultrathin Zn foils (20 μm). The superior rate capability and long-term cycle stability of Zn–MnO2 full cells further prove the effectiveness of Gly in stabilizing Zn anode. This work sheds light on additive designing from the specific roles of polar groups for AZIBs. [ABSTRACT FROM AUTHOR]

Biomass is regarded as promising low-cost carbon source while the direct biomass pyrolysis usually shows low-surface-area or even non-porous, and therefore not useful for CO2 capture. Here, garlic peel was chemically activated by KOH to obtain carbons via the variation of temperature and KOH mass ratio, and the pore structure of carbons was evaluated by N2 adsorption. Importantly, carbon (gC-47) activated by four-fold KOH in mass at 700 °C exhibits well-developed porosity with surface area and pore volume of 1638 m2/g and 0.88 cm3/g, respectively. However, carbon (gC-27) activated by two-fold KOH in mass with lower surface area and pore volume but higher microporosity shows the highest CO2 uptake of 4.1 mmol/g at 25 °C and 1 bar. The results indicated that the critical factor for CO2 capture on carbon is microporosity not the traditionally believed surface area or pore volume, and an increase in porosity with special micropore size and moderate surface area will lead to the enhancement of CO2 uptake. This research provides significant guidance in designing adsorbents for CO2 capture, and the carbons from garlic peel can provide feasible option for CO2 capture with low-cost, environment friendship, and high capture capability. [ABSTRACT FROM AUTHOR]

Pantoea stewartii subsp. stewartii (Pnss) and P. stewartii subsp. indologenes (Pnsi) are closely related plant pathogens that differ in their host specificities. Pnss is the causal agent of Stewart's wilt of corn, whereas Pnsi causes disease on millets but not corn. Comparative genomics is a valuable method for characterizing the differences between genomes, but there are few studies on this important quarantine pathogen. Here, we compared publicly available genomes of seven strains of Pnss and three strains of Pnsi. Pan- and core-genome analyses showed that strains isolated from close geographical regions are more similar in their genome structures. Gene content and collinearity analyses further revealed numerous strain-specific genes. In particular, the Pnss type strain DC283 contained over 1200 additional genes compared with other strains. Importantly, we also identified eleven genes that are only present in Pnsi genomes and thus may be useful to distinguish between Pnss and Pnsi strains. Overall, this study characterized the common and distinct genomic features of Pnss and Pnsi, which lay the foundation for future development of molecular methods to detect the Stewart's wilt pathogen in maize for quarantine regulations and distinguish its two subspecies. [ABSTRACT FROM AUTHOR]

Industrial robots (IRs) are the important driving force to enable the production activities more automotive and highly efficient in modern manufacturing systems. However, in order to realize the effective employment and intelligent configuration of IRs in cloud manufacturing environment, it is required that the sustainable manufacturing capabilities of IRs can be described in a unified and formal manner. In this paper, a unified sustainable manufacturing capability (SMC) of the IR model is constructed in terms of functional attributes, structural information, activities and process condition. A hybrid logic description method integrating Ontology Web Language with dynamic description logic (DLL) is adopted to provide a semantical representation to both the static and dynamic characteristics of SMC. An interval-state description method is proposed to present energy consumption during the IR's process in sections. Based on the constructed model, three types of rules are defined to reason the capability of IRs, including stability, energy consumption and production capacity. Finally, a cloud-based prototype system architecture is illustrated. An IR service platform is developed and implemented to verify the proposed model and the defined rules. [ABSTRACT FROM AUTHOR]

A new reversible colorimetric and fluorescent chemosensor MMIP based on a simple Schiff base has been successfully synthesized. MMIP exhibited high selectivity and sensitivity towards Ag, Cu and Hg ions with a short response time in DMSO/HO (1/1, v/v) solution among various metal ions, and the results could be monitored directly by naked eyes. The binding stoichiometry between MMIP and Ag/Hg/Cu has been determined to be 1:2 by Job's plot and FT-IR analysis. MMIP could effectively detect Ag, Cu and Hg over a wide pH range of 3-10. The good linear correlations were obtained in the concentration ranges of 0-20 μM for Ag, Cu and Hg. Thus sensor MMIP could be potentially used for the quantification of Ag, Cu and Hg in aqueous solution. [ABSTRACT FROM AUTHOR]

A phenylamine-oligothiophene-based fluorescent chemosensor I3TEA was reported. This sensor exhibited highly selective and fast detection of Hg ion in MeCN/HO (8/2, v/v) solution through fluorescence quenching. The detection was unaffected by the other competitive metal cations. The low detection limit was found to be 5.92 × 10 M. In addition, the recognition process is reversible and confirmed by EDTA experiment. [ABSTRACT FROM AUTHOR]

A fast-responsive fluorescent phenylamine-oligothiophene sensor 2TBDA was reported. This sensor exhibited highly selective and sensitive detection of Hg ion in THF/HO (7/3, v/v) solution through fluorescence quenching. The detection was not affected by the coexistence of other competitive metal ions. In addition, the detection limit was found to be as low as 3.841 × 10 M. [ABSTRACT FROM AUTHOR]

The purpose of this study was to develop an injectable in situ liquid crystal formulation for intra-articular (IA) administration, and in situ forming a viscous liquid crystalline gel with long-term release of sinomenine hydrochloride (SMH) upon water absorption. The pseudo-ternary phase diagram of phytantriol (PT)-ethanol (ET)-water was constructed, and isotropic solutions were chosen for further optimization. The physicochemical properties of isotropic solutions were evaluated, and the phase structures of liquid crystalline gels formed by isotropic solutions in excess water were confirmed by crossed polarized light microscopy (CPLM) and small-angle X-ray scattering (SAXS). In vitro drug release studies were conducted by using a dialysis membrane diffusion method. The optimal in situ cubic liquid crystal (ISV) (PT/ET/water, 64:16:20, w/ w/ w) loaded with 6 mg/g of SMH showed a suitable pH, showed to be injectable, and formed a cubic liquid crystalline gel in situ with minimum water absorption within the shortest time. The optimal ISV was able to sustain the drug release for 6 days. An in situ hexagonal liquid crystal (ISH) system was prepared by addition of 5% vitamin E acetate (VitEA) into PT in the optimal ISV system to improve the sustained release of SMH. This ISH (PT/VitEA/ET/water, 60.8:3.2:16:20, w/ w/ w/ w) was an injectable isotropic solution with a suitable pH range. The developed ISH was found to be able to sustain the drug release for more than 10 days and was suitable for IA injection for the treatment of rheumatoid arthritis (RA). [ABSTRACT FROM AUTHOR]

This paper presents a novel real-time measuring method to measure the micro-displacement of a rotating cutter in precise piston noncylinder pinhole boring. A noncontact and interference-free approach is used to dynamically collect data on the cutter's displacement by using two perpendicular electric eddy sensors. Data from the sensors are processed by using the corresponding algorithm according to the position of the boring cutter. The mathematical model is established, and the error is separated by using the error separation technique and then compensated. A typical application of the method in the smart boring bar with the embedded giant magnetostrictive actuator is demonstrated. Several experiments are carried out, and the results indicate that the real-time measuring method can measure the micro-displacement of a rotating boring cutter effectively. [ABSTRACT FROM AUTHOR]

Nine polymorphic microsatellites markers were identified for Galaxea fascicularis symbionts and characterized in 29 samples from two populations. Four of them were derived from coral genome with 5-11 alleles, and the expected and observed heterozygosities ranging 0.67-0.89 and 0.25-0.69 respectively. Five were derived from zooxanthella genome amplified 0-3 alleles/locus per individual, while 2-4 alleles/locus with totally 13 genotypes in the two populations, which likely implied multiple DNA-polymorphic Symbiodinium species associated with single host and the populations. The genetic diversity of the two coral host populations was significantly greater than that of zooxanthella populations. These markers should be useful in various genetic applications involving both the coral host and the zooxanthella. [ABSTRACT FROM AUTHOR]

The integration of derivatives of granular metal-organic frameworks (MOFs) and an electrically conductive carbon substrate is an effective way to circumvent the deficiency of powdered pristine MOFs or MOF-derived carbon in practical application. The authors describe the use of graphite oxide (GO) as a substrate for in-situ assembly with the zeolitic imidazole framework ZIF-67. The GO and ZIF-67 composites were converted, via pyrolysis, into reduced graphite oxide loaded with Co/N-co-doped carbon polyhedrons (ZIF-67C@rGO). By using various amounts of GO, a series of ZIF-67C@rGO-x with different fractions of GO were synthesized and utilized as electrode modifiers for the detection of the antibiotic metronidazole (MNZ). The results revealed that the ZIF-67C@rGO-0.06 display best sensing performance. This is likely to be due to its hierarchically open pores, abundant active sites and good electrical conductivity. The sensor, best operated near a working potential around −0.6 V (vs. SCE), has a linear response in the 0.5 to 1000 μM MNZ concentration range and a 0.05 μM detection limit. The sensor was applied to the analysis of pharmaceutical samples where it showed excellent selectivity, good repeatability and satisfying recoveries. [ABSTRACT FROM AUTHOR]