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The state-of-the-art lithium-ion capacitors (LICs), consisting of high-capacity battery-type anode and high-rate capacitor-type cathode, can deliver high energy density and large power density when comparing with traditional supercapacitors and lithium-ion batteries, respectively. However, the ion kinetics mismatch between cathode and anode leads to unsatisfied cycling lifetime and anode degradation. Tremendous efforts have been devoted to solving the abovementioned issue. One promising strategy is altering high conductive hard carbon anode with excellent structural stability to match with activated carbon cathode, assembling dual-carbon LIC. In this contribution, one-pot in-situ expansion and heteroatom doping strategy was adopted to prepare sheet-like hard carbon, while activated carbon was obtained involving activation. Ammonium persulfate was used as expanding and doping agent simultaneously. While furfural residues (FR) were served as carbon precursor. The resulting hard carbon (FRNS-HC) and activated carbon (FRNS-AC) show excellent electrochemical performance as negative and positive electrodes in a lithium-ion battery (LIB). To be specific, 374.2 mAh g−1 and 123.1 mAh g−1 can be achieved at 0.1 A g−1 and 5 A g−1 when FRNS-HC was tested as anode. When combined with a highly porous carbon cathode (SBET = 2961 m2 g−1) synthesized from the same precursor, the LIC showed high specific energy of 147.67 Wh kg−1 at approximately 199.93 W kg−1, and outstanding cycling life with negligible capacitance fading over 1000 cycles. This study could lead the way for the development of heteroatom-doped porous carbon nanomaterials applied to Li-based energy storage applications.

The fructose-to-furfural transformation is facing major challenges in the selectivity and high efficiency. Herein, we have developed a simple and effective approach for the selective conversion of fructose to furfural using Hβ zeolite modified by organic acids for dealuminization to regulate its textural and acidic properties. It was found that citric acid-dealuminized Hβ zeolite possessed high specific surface areas, wide channels and high Brønsted acid amount, which facilitated the selective conversion of fructose to furfural with a maximum yield of 76.2% at 433 K for 1 h in the γ-butyrolactone (GBL)-H2O system, as well as the concomitant formation of 83.0% formic acid. The 13C-isotope labelling experiments and the mechanism revealed that the selective cleavage of C1–C2 or C5–C6 bond on fructose was firstly occurred to form pentose or C5 intermediate by weak Brønsted acid, which was then dehydrated to furfural by strong Brønsted acid. Also this dealuminized Hβ catalyst showed the great recycling performance and was active for the conversion of glucose and mannose.

The component analysis and structure characterization of complex mixtures of biomass conversion remain a challenging work. Hence, developing effective and easy to use techniques is necessary. Diffusion-ordered NMR spectroscopy (DOSY) is a non-selective and non-invasive method capable of achieving pseudo-separation and structure assignments of individual compounds from biomass mixtures by providing diffusion coefficients (D) of the components. However, the conventional 1H DOSY NMR is limited by crowded resonances when analyzing complex mixtures containing similar chemical structure resulting in similar coefficient. Herein we describe the application of an advanced diffusion NMR method, Pure Shift Yielded by CHirp Excitation DOSY (PSYCHE-iDOSY), which can record high-resolution signal diffusion spectra efficiently separating compounds in model and genuine mixture samples from cellulose, hemicellulose and lignin. Complicated sets of isomers (d-glucose/d-fructose/d-mannose and 1,2-/1,5-pentadiol), homologous compounds (ethylene glycol and 1,2-propylene glycol), model compounds of lignin, and a genuine reaction system (furfuryl alcohol hydrogenolysis with ring opening) were successfully separated in the diffusion dimension. The results show that the ultrahigh-resolution DOSY technique is capable of detecting and pseudo-separating the mixture components of C5/C6 sugar conversion products and its derivative hydrogenation/hydrogenolysis from lignocellulose biomass.

Sustainable development based on the value-added utilization of furfural residues (FRs) is an effective way to achieve a profitable circular economy. This comprehensive work highlights the potential of FRs as precursor to prepare porous carbons for high performance supercapacitors (SCs). To improve the electrochemical performance of FR-based carbon materials, a facile route based on methanol pretreatment coupled with pre-carbonization and followed KOH activation is proposed. More defects could be obtained after methanol treatment, which is incline to optimize textural structure. The activated methanol treated FR-based carbon materials (AFRMs) possess high specific surface area (1753.5 m2 g−1), large pore volume (0.85 cm3 g−1), interconnected micro/mesoporous structure, which endow the AFRMs with good electrochemical performance in half-cell (326.1 F g−1 at 0.1 A g−1, 189.4 F g−1 at 50 A g−1 in 6 mol L−1 KOH). The constructed symmetric SCs based on KOH, KOH–K3Fe(CN)6 and KOH-KI electrolyte deliver energy density up to 8.9, 9.9 and 10.6 Wh kg−1 with a capacitance retention of over 86% after 10,000 cycles. Furthermore, the self-discharge can be restrained by the addition of K3Fe(CN)6 and KI in KOH electrolyte. This study provides an effective approach for high-valued utilization of FR waste.

Ternary deep eutectic solvents (TDESs) comprising choline chloride (ChCl), glycerol and l-arginine were synthesized as catalysts and solvents for the conversion of d-glucosamine (GlcNH2) into deoxyfructosazine (DOF). The interactions between these three components in the prepared TDESs were studied by 1H-, 35Cl-NMR spectra and 1H diffusion-ordered spectroscopy (DOSY) measurements. The chemical shift changes of active hydrogen in the 1H-NMR spectra of TDES system and widening of signals in the 35Cl-NMR spectra confirmed the hydrogen bonding interaction between the components, which was further supported by the decrease of diffusion coefficients (D) of the TDES components according to 1H DOSY measurements. The influences of reaction temperature and l-arginine content in the TDESs on the yield of DOF were also studied. The experimental results have shown that when the molar ratio of ChCl, glycerol, and l-arginine was 1:2:0.1, DOF was the major product with a yield of 22.6% at 90 °C for 120 min. The chemical shift titration indicated that the carboxyl group of l-arginine in the TDES is the catalytical active site, so the mechanism of the catalytic reaction between GlcNH2 and the TDES was proposed. Moreover, a reaction intermediate, dihydrofructosazine, was identified in the self-condensation reaction of GlcNH2 by an in situ 1H NMR technique.

Circular RNAs (circRNAs) are a novel class of endogenous noncoding RNAs that play important roles in gene expression regulation. This study aimed to evaluate the potential role of circRNAs in decidual tissue of patients with early recurrent miscarriage (RM). We constructed circRNA expression profiles in decidual tissue using microarray data. A total of 123 differentially expressed circRNAs, including 78 upregulated and 45 downregulated circRNAs were detected in the early RM group compared with the control group (P

Hydrogen production by steam reforming of ethylene glycol (EG) at 300 °C was investigated over SiO2 and CeO2 supported Pt–Ni bimetallic catalysts prepared by incipient wetness impregnation methods. It was observed that impregnation sequence of Pt and Ni can affect the performance of catalysts apparently. Catalyst with Pt first and then Ni addition showed higher EG conversion and H2 yield owing to the Ni enrichment on the surface and the proper interaction between Pt and Ni. It was observed that although SiO2 supported catalysts exhibited better activity and H2 selectivity, CeO2 supported ones had better stability. This is attributed to the less coke formation on CeO2. Increasing Pt/Ni ratio enhanced the reaction activity, and Pt3–Ni7 catalysts with 3 wt% Pt and 7 wt% Ni showed the highest activity and stability. Ni surficial enrichment facilitated the C—C bond rupture and water gas shift reactions; and Pt addition inhibited methanation reaction. Electron transfer and hydrogen spillover from Pt to Ni suppressed carbon deposition. These combined effects lead to the excellent performance of Pt3–Ni7 supported catalysts. Keywords: Ethylene glycol, Steam reforming, Pt–Ni bimetallic catalyst, Hydrogen production, Synergistic effect

Hydrothermal carbonization (HTC) is a valuable approach to convert furfural residue (FR) into carbon material. The prepared biochars are usually characterized comprehensively, while the stock process water still remains to be studied in detail. Herein, a NMR study of the main components in stock process water generated at different HTC reaction conditions was reported. Various qualitative and quantitative NMR techniques (1H and 13C NMR, 1H–1H COSY and 1H13C HSQC etc.) especially 1D selective gradient total correlation spectroscopy (TOCSY NMR) were strategically applied in the analysis of HTC stock process water. Without separation and purification, it was demonstrated that the main detectable compounds are 5-hydroxymethylfurfural, formic acid, methanol, acetic acid, levulinic acid, glycerol, hydroxyacetone and acetaldehyde in this complicate mixture. Furthermore, the relationship between the concentration of major products and the reaction conditions (180–240 °C at 8 h, and 1–24 h at 240 °C) was established. Finally, reasonable reaction pathways for hydrothermal conversion of FR were proposed based on this result and our previously obtained characteristics of biochars. The routine and challenging NMR methods utilized here would be an alternative other than HPLC or GC for biomass conversion research and can be extended to more studies. Keywords: NMR, Hydrothermal carbonization, Furfural residue, Stock process water