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Non-flow aqueous zinc-bromine batteries without auxiliary components (e.g., pumps, pipes, storage tanks) and ion-selective membranes represent a cost-effective and promising technology for large-scale energy storage. Unfortunately, they generally suffer from serious diffusion and shuttle of polybromide (Br−, Br3−) due to the weak physical adsorption between soluble polybromide and host carbon materials, which results in low energy efficiency and poor cycling stability. Here, we develop a novel self-capture organic bromine material (1,1′-bis [3-(trimethylammonio)propyl]-4,4′-bipyridinium bromine, NVBr4) to successfully realize reversible solid complexation of bromide components for stable non-flow zinc-bromine battery applications. The quaternary ammonium groups (NV4+ ions) can effectively capture the soluble polybromide species based on strong chemical interaction and realize reversible solid complexation confined within the porous electrodes, which transforms the conventional “liquid–liquid” conversion of soluble bromide components into “liquid–solid” model and effectively suppresses the shuttle effect. Thereby, the developed non-flow zinc-bromide battery provides an outstanding voltage platform at 1.7 V with a notable specific capacity of 325 mAh g−1NVBr4 (1 A g−1), excellent rate capability (200 mAh g−1NVBr4 at 20 A g−1), outstanding energy density of 469.6 Wh kg−1 and super-stable cycle life (20,000 cycles with 100% Coulombic efficiency), which outperforms most of reported zinc-halogen batteries. Further mechanism analysis and DFT calculations demonstrate that the chemical interaction of quaternary ammonium groups and bromide species is the main reason for suppressing the shuttle effect. The developed strategy can be extended to other halogen batteries to obtain stable charge storage.

Abstract The high redox potential of Zn0/2+ leads to low voltage of Zn batteries and therefore low energy density, plaguing deployment of Zn batteries in many energy-demanding applications. Though employing high-voltage cathode like spinel LiNi0.5Mn1.5O4 can increase the voltages of Zn batteries, Zn2+ ions will be immobilized in LiNi0.5Mn1.5O4 once intercalated, resulting in irreversibility. Here, we design a polymer hetero-electrolyte consisting of an anode layer with Zn2+ ions as charge carriers and a cathode layer that blocks the Zn2+ ion shuttle, which allows separated Zn and Li reversibility. As such, the Zn‖LNMO cell exhibits up to 2.4 V discharge voltage and 450 stable cycles with high reversible capacity, which are also attained in a scale-up pouch cell. The pouch cell shows a low self-discharge after resting for 28 days. The designed electrolyte paves the way to develop high-voltage Zn batteries based on reversible lithiated cathodes.

Abstract Effective therapeutic targets and early diagnosis are major challenges in the treatment of gastrointestinal tract (GIT) cancers. SALL4 is a well-known transcription factor that is involved in organogenesis during embryonic development. Previous studies have revealed that SALL4 regulates cell proliferation, survival, and migration and maintains stem cell function in mature cells. Additionally, SALL4 overexpression is associated with tumorigenesis. Despite its characterization as a biomarker in various cancers, the role of SALL4 in GIT cancers and the underlying mechanisms are unclear. We describe the functions of SALL4 in GIT cancers and discuss its upstream/downstream genes and pathways associated with each cancer. We also consider the possibility of targeting these genes or pathways as potential therapeutic options for GIT cancers.

The negative electrode reversibility limits the lifespan of Zn metal batteries. Here, authors report an aqueous electrolyte with a reverse micelle structure that improves the reversibility of the Zn metal anode enabling the production of an ampere-hour-level pouch cell with five months lifetime.

Accurate thermochemical properties for chemical species are of vital importance in combustion chemistry research. Group additivity approaches are widely used to generate thermochemistry data used in chemical kinetic models, but this approach has limited accuracy. Following on previous studies by the combustion community, we performed electronic structure calculations to obtain reliable thermochemistry data for a large set of molecules taken from a well-established chemical kinetic model. The developed database consists of 1340 species that contain up to 18 and 5 carbon and oxygen atoms, respectively. The M06-2X/aug-cc-pVTZ level of theory was used for the geometry optimizations, vibrational frequency calculations, and dihedral angle scans. The potential energy of the different species was further refined with different composite methods, and the G3 method with the atomization reaction approach was selected to calculate the enthalpy of formation at 0 K. This information was then used in statistical thermodynamics calculations to obtain standard enthalpies of formation and entropy, as well as heat capacities at different temperatures. Our thermochemistry data exhibits good agreement with existing values in the literature, verifying the accuracy of our approach. Comparisons against group additivity (GA) method are also presented. The database of thermochemistry quantities developed in this study can be used to improve the training GA or machine learning models. The impact of the developed dataset is illustrated by examining the variation in ignition delay times using the updated thermochemistry values.

d-pantolactone is an intermediate in the synthesis of d-pantothenic acid, which is known as vitamin B5. The commercial synthesis of d-pantolactone is carried out through the selective resolution of dl-pantolactone catalyzed by lactone hydrolase. In contrast to a kinetic resolution approach, the deracemization of dl-pantolactone is a simpler, greener, and more sustainable way to obtain d-pantolactone with high optical purity. Herein, an efficient three-enzyme cascade was developed for the deracemization of dl-pantolactone, using l-pantolactone dehydrogenase from Amycolatopsis methanolica (AmeLPLDH), conjugated polyketone reductase from Zygosaccharomyces parabailii (ZpaCPR), and glucose dehydrogenase from Bacillus subtilis (BsGDH). The AmeLPLDH was used to catalyze the dehydrogenated l-pantolactone into ketopantolactone; the ZpaCPR was used to further catalyze the ketopantolactone into d-pantolactone; and glucose dehydrogenase together with glucose fulfilled the function of coenzyme regeneration. All three enzymes were co-expressed in E. coli strain BL21(DE3), which served as the whole-cell biocatalyst. Under optimized conditions, 36 h deracemization of 1.25 M dl-pantolactone d-pantolactone led to an e.e.p value of 98.6%, corresponding to productivity of 107.7 g/(l·d).

The interactions between water molecules, electrode materials and anions are essential yet challenging for aqueous dual ion batteries. Here, the authors demonstrate the voltage manipulation of dual ion batteries through matching intercalation energy and solvation energy of different anions.

Abstract Background α,β-Unsaturated aldehydes are widely used in the organic synthesis of fine chemicals for application in products such as flavoring agents, fragrances and pharmaceuticals. In the selective oxidation of α,β-unsaturated alcohols to the corresponding α,β-unsaturated aldehydes, it remains challenging to overcome poor selectivity, overoxidation and a low atom efficiency in chemical routes. Results An E. coli strain coexpressing the NADP+-specific alcohol dehydrogenase YsADH and the oxygen-dependent NADPH oxidase TkNOX was constructed; these components enabled the NADP+ regeneration and catalyzed the oxidation of 100 mM 3-methyl-2-buten-1-ol to 3-methyl-2-butenal with a yield of 21.3%. The oxygen supply was strengthened by introducing the hemoglobin protein VsHGB into recombinant E. coli cells and replacing the atmosphere of the reactor with pure oxygen, which increased the yield to 51.3%. To further improve catalytic performance, the E. coli cells expressing the multifunctional fusion enzyme YsADH-(GSG)-TkNOX-(GSG)-VsHGB were generated, which completely converted 250 mM 3-methyl-2-buten-1-ol to 3-methyl-2-butenal after 8 h of whole-cell oxidation. The reaction conditions for the cascade biocatalysis were optimized, in which supplementation with 0.2 mM FAD and 0.4 mM NADP+ was essential for maintaining high catalytic activity. Finally, the established whole-cell system could serve as a platform for the synthesis of valuable α,β-unsaturated aldehydes through the selective oxidation of various α,β-unsaturated alcohols. Conclusions The construction of a strain expressing the fusion enzyme YsADH-(GSG)-TkNOX-(GSG)-VsHGB achieved efficient NADP+ regeneration and the selective oxidation of various α,β-unsaturated alcohols to the corresponding α,β-unsaturated aldehydes. Among the available redox enzymes, the fusion enzyme YsADH-(GSG)-TkNOX-(GSG)-VsHGB has become the most recent successful example to improve catalytic performance in comparison with its separate components.

With the triboelectric nanogenerator developing in recent years, it has gradually become a promising alternative to fossil energy and batteries. Its rapid advancements also promote the combination of triboelectric nanogenerators and textiles. However, the limited stretchability of fabric-based triboelectric nanogenerators hindered their development in wearable electronic devices. Here, in combination with the polyamide (PA) conductive yarn, polyester multifilament, and polyurethane yarn, a highly stretchable woven fabric-based triboelectric nanogenerator (SWF-TENG) with the three elementary weaves is developed. Different from the normal woven fabric without elasticity, the loom tension of the elastic warp yarn is much larger than non-elastic warp yarn in the weaving process, which results in the high elasticity of the woven fabric coming from the loom. Based on the unique and creative woven method, SWF-TENGs are qualified with excellent stretchability (up to 300%), flexibility, comfortability, and excellent mechanical stability. It also exhibits good sensitivity and fast responsibility to the external tensile strain, which can be used as a bend–stretch sensor to detect and identify human gait. Its collected power under pressure mode is capable of lighting up 34 light-emitting diodes (LEDs) by only hand-tapping the fabric. SWF-TENG can be mass-manufactured by using the weaving machine, which decreases fabricating costs and accelerates industrialization. Based on these merits, this work provides a promising direction toward stretchable fabric-based TENGs with wide applications in wearable electronics, including energy harvesting and self-powered sensing.

The importance of yeast old yellow enzymes is increasingly recognized for direct asymmetric reduction of (E/Z)-citral to (R)-citronellal. As one of the most performing old yellow enzymes, the enzyme OYE3 from Saccharomyces cerevisiae S288C exhibited complementary enantioselectivity for the reduction of (E)-citral and (Z)-citral, resulting in lower e.e. value of (R)-citronellal in the reduction of (E/Z)-citral. To develop a novel approach for the direct synthesis of enantio-pure (R)-citronellal from the reduction of (E/Z)-citral, the enzyme OYE3 was firstly modified by semi-rational design to improve its (R)-enantioselectivity. The OYE3 variants W116A and S296F showed strict (R)-enantioselectivity in the reduction of (E)-citral, and significantly reversed the (S)-enantioselectivity in the reduction of (Z)-citral. Next, the double substitution of OYE3 led to the unique variant S296F/W116G, which exhibited strict (R)-enantioselectivity in the reduction of (E)-citral and (E/Z)-citral, but was not active on (Z)-citral. Relying on its capability discriminating (E)-citral and (Z)-citral, a new cascade reaction catalyzed by the OYE3 variant S296F/W116G and glucose dehydrogenase was developed, providing the enantio-pure (R)-citronellal and the retained (Z)-citral after complete reduction of (E)-citral.

Allergy to nickel based alloy arch wires, which is largely induced by corrosion behavior, can cause severe problems during the orthodontic treatment. However, no consensus has been reached in the comparison of anti-corrosion behavior between Nickel-Titanium (NiTi) and Copper Nickel-Titanium (CuNiTi) alloy arch wires. Herein, the anti-corrosion behavior of NiTi and CuNiTi arch wires was simultaneously studied in artificial saliva under loading stress to simulate clinical conditions. Scanning electron microscope (SEM) was utilized to detect the surface morphology and following x-ray diffraction (XRD), electrochemical impedance spectroscopy (EIS) as well as x-ray photoelectron spectroscopy (XPS) were used to evaluate the potential anti-corrosion tendency of the arch wires, implying that CuNiTi arch wire had more defects on the surface yet intriguingly less release of Ni compared with NiTi arch wire after test. Both groups of arch wires were more corroded when loaded with clinic-simulating stress, nevertheless, the doping of Cu element can reduce the release of Ni to some extent, which is conducive to lowering the probability of metal allergy and supplying meaningful instructions for the manufactories and orthodontists.

Combining multisource cooperation and link-adaptive regenerative techniques, a novel protocol is developed capable of achieving diversity order up to the number of cooperating users and large coding gains. The approach relies on a two-phase protocol. In Phase 1, cooperating sources exchange information-bearing blocks, while in Phase 2, they transmit reencoded versions of the original blocks. Different from existing approaches, participation in the second phase does not require correct decoding of Phase 1 packets. This allows relaying of soft information to the destination, thus increasing coding gains while retaining diversity properties. For any reencoding function the diversity order is expressed as a function of the rank properties of the distributed coding strategy employed. This result is analogous to the diversity properties of colocated multi-antenna systems. Particular cases include repetition coding, distributed complex field coding (DCFC), distributed space-time coding, and distributed error-control coding. Rate, diversity, complexity and synchronization issues are elaborated. DCFC emerges as an attractive choice because it offers high-rate, full spatial diversity, and relaxed synchronization requirements. Simulations confirm analytically established assessments.