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In this paper, a flower‐like molybdenum disulfide material was prepared by hydrothermal method and was first used as adsorbents in the solid‐phase extraction process for enriching N‐nitrosoamines. Molybdenum disulfide exhibited three‐dimensional petal‐like microspheres with about 500 nm in diameter. The relevant analyte extraction and elution parameters (sample volumes, solution pH, washing solvents, elution solvents, and elution volumes) were optimized to improve the solid‐phase extraction efficiency. The solid‐phase extraction process coupled with high‐performance liquid chromatography‐tandem mass spectrometry for determining N‐nitrosoamines in environmental water samples was established. The limits of detection were in the range of 0.01–0.05 ng/mL. The satisfactory recoveries (68.9–106.1%) were obtained at three different spiked concentrations (2, 5, and 8 ng/mL) in water samples, and the relative standard deviations were between 1.96 and 8.38%. This proposed method not only showed high sensitivity and good reusability but also provided a new adsorbent for enriching trace N‐nitrosoamines in environmental water samples. [ABSTRACT FROM AUTHOR]

Sugar nucleotides are the principal building blocks for the synthesis of most complex carbohydrates and are crucial intermediates in carbohydrate metabolism. Uridine diphosphate (UDP) monosaccharides are among the most common sugar nucleotide donors and are transferred to glycosyl acceptors by glycosyltransferases or synthases in glycan biosynthetic pathways. These natural nucleotide donors have great biological importance, however, the synthesis and application of unnatural sugar nucleotides that are not available from in vivo biosynthesis are not well explored. In this review, we summarize the progress in the preparation of unnatural sugar nucleotides, in particular, the widely studied UDP-GlcNAc/GalNAc analogs. We focus on the "two-block" synthetic pathway that is initiated from monosaccharides, in which the first block is the synthesis of sugar-1-phosphate and the second block is the diphosphate bond formation. The biotechnological applications of these unnatural sugar nucleotides showing their physiological and pharmacological potential are discussed. [ABSTRACT FROM AUTHOR]

D-Glucuronyl C5-epimerase (C5-epi), which converts D-glucuronic acid to L-iduronic acid, is a crucial enzyme in the preparation of bioengineered heparin, which provides an alternative way to produce safer heparins. Herein, we provided an efficient way to measure the activity of cyanogen bromide-immobilized C5-epi based on proton nuclear magnetic resonance (NMR) analysis of perdeutero N-sulfoheparosan C5-epimerization. In this method, reactions catalyzed by C5-epi could be monitored by real-time 1 D NMR according to the peak intensity change of H-5 from IdoA and GlcA residues in the 1H NMR spectrum, which is nondestructive of sample and also serves the kinetic property evaluation of immobilized C5-epi. [ABSTRACT FROM AUTHOR]

• Revealing the transfer machanism of various forms of water and establishing a water transfer model. • The generation of hydration products can be quantitatively determined by the changes in different forms of water. • It is recommended to choose a l = 9% and T = 7d as the on-site mixing conditions for centrifugal dewatering of clay in slurry shield tunneling. This study investigates the water transfer mechanism of quicklime modified centrifugal dewatering clay. A small-scale centrifuge device was used to investigate the change of bound water content in modified clay under different laboratory test conditions including quicklime content and curing age, and analyze the water transfer mechanism in the process of quicklime treatment, and its impact on clay properties. The results show that the content of pore water decreased by 6.2% ∼ 16.9%, the content of bound water increased by 4.2% ∼ 12.9%, and the content of hydration water increased by 6.1% ∼ 14.1% due to hydration reaction caused by the quicklime. The increase of quicklime content facilitates the conversion of free water into bound water and hydration water in a relatively short time. The pozzolanic reaction occurs on the surface of the clay particles to absorb free water and convert it into bound water, while part of Ca (OH) 2 crystals generated by hydration reaction adhere to the surface of clay particles, grow into needle-shape and fibrous structures, and absorb free pore water and convert it into hydration water. For field applications, the mixing percentage of quicklime is recommended to be below 9% by dry weight. From the cost perspective, 7-day curing age is recommended in the field. The essence of quicklime modification is to transform the free water with relatively low pF potential energy into the bound water and hydration water with relatively high pF potential energy. A schematic diagram of water transfer mechanism was also proposed in this study for quicklime modified clay and validated using the aforementioned experimental data. [ABSTRACT FROM AUTHOR]

• SERS-based innovative nanohybrid platforms are promising tools in safety control of food supply chain. • Summarizing the significance of function-oriented design and applications of versatile hybrid SERS substrates in addressing concerns in food supply chain safety and beyond. • Systematic review of nanohybrid SERS platform design, fabrication, properties and functions. • The potential of SERS-based innovative nanohybrid platforms for food supply chain safety and security is discussed. Agri-food safety incidents not only threaten the life and health of consumers but also seriously hinder the development of the food supply chain. It is generally accepted that the development of rapid and reliable detection techniques ensures timely recognition and control of food hazards. Surface-enhanced Raman scattering (SERS) is a fast, sensitive, and fingerprinting vibrational spectroscopy with advantageous potentials for non-destructive and single-molecule detection of agri-food products. The physicochemical properties of SERS substrates determine the sensing performance and reliability of the detection methodology. However, traditional SERS substrates based on mono-noble metals exhibit poor sensing stability and limited specificity, not mentioning their poor availability and low cost-efficiency towards commercial industrialization. These intrinsic drawbacks hamper the use of noble metal SERS substrates for sensitive food detection in complicated scenes. With the emergence of various functional nanomaterials, the development of rationally designed and fabricated nanohybrid SERS platforms represents a promising frontier of SERS technology for highly sensitive, interference-free, multiplexed, and reliable food detection. Standing on the challenges and opportunities of SERS technology in food detection, this timely review firstly discloses the significance of function-oriented design and applications of versatile hybrid SERS substrates for addressing principal concerns in food detection and beyond. Thereafter, the various categories, hybridization strategies, and featured functionalities of the current hybrid SERS substrates have been well summarized in detail. Next, the advances in the application of hybrid SERS platforms for the detection and control of food supply chain safety factors have been fully reviewed and discussed. Finally, this review ended with a comprehensive and in-depth summary of the promising prospects and current challenges of nanohybrid SERS platforms in the agri-food industry. Overall, this contribution has demonstrated that nanohybridization endows SERS technique with desirable versatility beyond exquisite sensing performance, holding great promise for agri-food safety assurance. [ABSTRACT FROM AUTHOR]

• Superhydrophobic surface is realized by electrodeposition, anodization and thiol modification. • A salt particle takes doughnut shape on superhydrophobic surface. • Liquid coating has better corrosion inhibition than superhydrophobic surface. Steel corrosion poses a significant challenge, and coating plays a pivotal role in preventing it. In this study, instead of using solid materials, we explored air-based coating inspired by lotus leaves and liquid-based coating inspired by pitcher plants, collectively known as fluid infused coatings, to protect steel from corrosion. Initially, Zn metal is prepared through electrochemical deposition, followed by anodization of the zinc metal to achieve a radially structured surface of zinc oxide. Surface modification is then conducted to create a superhydrophobic surface (SHS) by storing gas. The liquid coating is obtained by infusing the liquid oil into the superhydrophobic matrix by replacing air phase. When subjected to a salt spray, the resulting salt particle takes the form of doughnut rather than a spreading pancake shape on bare steel plate. From an adhesion standpoint, the contact area between the doughnut-shaped salt particle and SHS is significantly smaller compared to the pancake-shaped salt particle on bare steel surface. As a result, the salt particle tends to detach from SHS. Corrosion protection investigations are carried out on these fluid-based coatings using electrochemical techniques and other methodologies, revealing that the liquid-based coating system exhibits significantly larger efficacy compared to the gas-based fluid coating. [Display omitted] [ABSTRACT FROM AUTHOR]

Byline: Anders Brink, Bingzhi Li, Mikko Hupa Deposits of unconverted particles in the heat recovery boilers used in the copper flash smelting process may cause operational problems. In this work, a dual-product layer shrinking-core-like particle model is presented. In this model the conversion can be solved from a single non-linear equation. Computational Fluid Dynamics (CFD) can provide detailed insight into the processes in the heat recovery boiler. Used with CFD, this particle conversion model can be used to study the effect of boiler design and process parameters on the depositing particles.

Byline: Bingzhi Li, Anders Brink, Mikko Hupa In the copper flash smelting process, deposition of dust particles can diminish the capacity of the heat recovery boiler. A deposit growth model was developed and implemented in a commercial CFD code to simulate deposition in a heat recovery boiler. In the model, a force balance of the particle landing on the wall is used as the deposition criterion. The thickness increase of the deposit layer is calculated from the mass flow of sticking particles. Simulations are used to demonstrate the applicability of the model. They also help in providing insight into the process.

[Display omitted] • The applications of biosensors in the detection of microcystins are reviewed. • The general strategy for the biosensing of microcystins is discussed. • Aptamers and antibodies are the most common way to recognize microcystins in biosensing. • Electrochemical and optical biosensors for microcystins are mostly developed. The blooming of cyanobacteria in aquatic environments can produce various cyanotoxins polluting soil and water, raising major concerns over environmental and human health issues. Microcystins (MCs) are one of the most toxic cyanotoxins, and the monitoring of MCs is critical for environmental protection and public health. Bio-inspired sensors, also known as biosensors, have become an emerging tool for the detection of MCs. Compared with conventional assays rely on centralized instruments and expensive reagents, biosensors are easier-to-use and more cost-effective, exhibiting high potential to be popularized in on-site and real-time MCs monitoring. Herein, the conventional methods for the MCs measurement were first briefly introduced, followed by the summarization of the recent trends in developing aptasensors and immunosensors targeting MCs, based on the recognition mechanisms towards MCs. Their common strategies and personalized highlights are discussed, to outline a general guide for designing MCs biosensors. Furthermore, the challenges in the biosensing of MCs regarding the specificity, sensitivity, simplicity, and stability are summarized to illustrate the future opportunities in this field. [ABSTRACT FROM AUTHOR]