Publications by authors named "Heli Cheng"

Article Synopsis
  • Carbonyl desaturation is a key reaction in organic synthesis, but traditional methods often require complicated multi-step processes or harsh conditions.
  • Researchers developed a new biocatalytic system using engineered 'ene'-reductases to streamline the desaturation of cyclohexanones into cyclohexenones, ensuring better stereochemical control.
  • This method operates under mild conditions, uses air for oxidation, and shows improved tolerance to sensitive functional groups and greater stereoselectivity compared to conventional catalysts.
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The ever-increasing demand for energy and environmental concerns have driven scientists to look for renewable and eco-friendly alternatives. Bio-based thermoelectric (TE) composite materials provide a promising solution to alleviate the global energy crisis due to their direct conversion of heat to electricity. Cellulose, the most abundant bio-polymer on earth with fascinating structure and desirable physicochemical properties, provides an excellent alternative matrix for TE materials.

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The unique properties of ionic liquids (ILs), such as structural tunability, good solubility, chemical/thermal stability, favorable biocompatibility, and simplicity of preparation, have led to a wide range of applications in the pharmaceutical and biomedical fields. ILs can not only speed up the chemical reaction process, improve the yield, and reduce environmental pollution but also improve many problems in the field of medicine, such as the poor drug solubility, product crystal instability, poor biological activity, and low drug delivery efficiency. This paper presents a systematic and concise analysis of the recent advancements and further applications of ILs in the pharmaceutical field from the aspects of drug synthesis, drug analysis, drug solubilization, and drug crystal engineering.

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Self-healing hydrogels have received considerable attention as a promising material for flexible electronic devices given their mechanical durability and structurally tunable properties. In this study, a highly stretchable self-healing hydrogel with dual cross-linking network was developed via borate ester bonds generated by polyvinyl alcohol and borax, and acylhydrazone bonds formed by aldehyde nanocellulose with adipic acid dihydrazide-modified alginate. Compared with the single network hydrogel composed of polyvinyl alcohol and borax, the introduction of dynamic acylhydrazone bonds greatly increases the flexibility of the hydrogel.

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Humidity sensors have been widely used for humidity monitoring in industry and agriculture fields. However, the rigid structure, nondegradability, and large dimension of traditional humidity sensors significantly restrict their applications in wearable fields. In this study, a flexible, strong, and eco-friendly bacterial cellulose-based humidity sensor (BPS) was fabricated using a two-step method, involving solvent evaporation-induced self-assembly and electrolyte permeation.

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The utilization of malonic acids in radical decarboxylative functionalization is still underexploited, and the few existing examples are primarily limited to bisdecarboxylative functionalization. While radical monodecarboxylative functionalization is highly desirable, it is challenging because of the difficulty in suppressing the second radical decarboxylation step. Herein, we report the successful radical monodecarboxylative C-C bond coupling of malonic acids with ethynylbenziodoxolone (EBX) reagents enabled by an masking strategy, affording synthetically useful 2(3)-furanones in satisfactory yields.

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Article Synopsis
  • Polycyclic aromatic hydrocarbons (PAHs) are linked to cancer risk and can be detected in human blood using a newly developed method involving pipette-tip solid phase extraction (PT-SPE) and gas chromatography-mass spectrometry (GC-MS).
  • This method employs a unique sorbent, a three-dimensional ionic liquid-ferrite functionalized graphene oxide nanocomposite, making it more efficient by using less solvent and blood sample compared to traditional techniques.
  • Results from analyzing 14 blood samples indicated that low-molecular-weight PAHs, particularly phenanthrene, naphthalene, and fluorene, were the most prevalent, showcasing the method's potential for clinical applications and exposure studies.
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Nanozymes merge nanotechnology with biology and provide a lower cost and higher stability options, compared to that of natural enzymes. However, nanozyme catalyzed polymerization under physiological conditions is still a big challenge due to heavy oxygen inhibition. In this study, the simple glucose oxidase system can effectively adjust oxygen concentration and generate hydrogen peroxide, which assists in the realization of nanozyme-catalyzed polymerization.

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A new anticoagulant agent was prepared by introducing sulfate groups into corn stover xylan through homogeneous reactions. Three organic solvents, N, N-dimethylformamide (DMF), dimethyl sulfoxide (DMSO) and formamide (FA), were adopted as reaction media, with the assistance of LiCl. Structural characterization by FT-IR and CNMR showed that xylan sulfate (XS) could be successfully synthesized with SO∙Pyridine (SO∙Py) complexes sulfation reagent in the three media.

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Poly (glycidylmethacrylate-divinylbenzene) microspheres were prepared by the two-staged swelling and polymerization method and applied to prepare anion exchange stationary phases. Methylamine, dimethylamine, trimethylamine, diethylamine and triethylamine were selected to prepare the quaternary ammonium groups of anion exchangers, respectively. The diameters and surface characteristics of microspheres were measured by scanning electron microscope and nitrogen adsorption-desorption measurements.

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