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To elucidate the effect of solution viscosity on the synthesis of Ni-phyllosilicate, polyacrylamide was incorporated to create a viscous aqueous medium containing of sodium metasilicate, nickel nitrate and NH 4 F. The enhanced viscosity promotes the dispersion of the initial formed crystal seeds and the growth of Ni-phyllosilicate, culminating in a Ni-rich NiPs-RT-6 of a high Ni content of up to 55.2 wt%. Residual polyacrylamide elimination was accomplished via calcination, concurrently enhancing metal-support interaction. The as-synthesized samples display a nanoflower morphology with nanospheres overlaid with numerous thin nanosheets. The relatively small Ni particles around 5.7 nm were obtained after reduction even at a very high Ni loading, owing to its strong metal-support interaction. NiPs-RT-6 achieves a CO 2 conversion of 75.9% at 450 °C, 0.1 MPa, 60 L g−1·h−1, which closely approximates thermodynamic equilibrium. The turn over frequency for CO 2 (TOF CO2) was substantial, calculated at 3.7 × 10−3 s−1, accompanied by activation energy (E a) of 80.6 kJ·mol–1. In-situ Diffuse Reflectance Infrared Fourier Transform Spectroscopy (DRIFTS) further disclosed that m -HCOO– serves as a crucial intermediate following a formate reaction pathway. With its high Ni content, finely distributed Ni particles, and strong metal-support interaction, NiPs-RT-6 demonstrates promising catalytic activity in CO 2 methanation. [Display omitted] • The room-temperature synthesis of Ni-phyllosilicate was achieved. • A viscous solvent of polyacrylamide significantly promoted the synthesis of Ni-phyllosilicate. • The reduced Ni-phyllosilicate retained small Ni particles at a high Ni content. • Polyacrylamide improved the catalytic performance of CO 2 methanation. [ABSTRACT FROM AUTHOR]

In this study, the FeCo layered double hydroxide/Sepiolite composite was successfully synthesized by a water bath approach which exhibited outstanding norfloxacin (NOR) degradation performance in presence of peroxymonosulfate (PMS). The reaction rate constant in the FeCo-LDH/Sepiolite/PMS system was 0.1644 min−1, which was around 1.78 times greater than that in the FeCo-LDH/PMS system. The introduction of the sepiolite carrier, which led to an increase in specific surface area and pore volume, was principally responsible for the considerable improvement in PMS activation efficiency. Moreover, the composite presented good stability and reusability. According to the results of the electron paramagnetic resonance (EPR) and quenching tests, the predominant reactive species in the FeCo-LDH/Sepiolite/PMS/NOR system were SO 4 •- and 1O 2. Furthermore, possible NOR degradation pathways and catalytic mechanism were proposed. In summary, our research provised new ideas in the synthesis of promising mineral based PMS catalyst for wastewater treatment. [Display omitted] • Sepiolite was first used as the carrier of FeCo-LDH to improve the catalytic activity. • Abundant reaction active sites were achieved in FeCo-LDH/sepiolite composite. • The synergistic effect of FeCo-LDH and sepiolite enhanced NOR degradation efficiency. [ABSTRACT FROM AUTHOR]

A novel CeO 2 /sepiolite (CeO 2 /SEP) composite with sepiolite as the support of CeO 2 was successfully prepared using a simple ammonia precipitation method for the photocatalytic degradation of tetracycline (TC) by loading CeO 2 nanoparticles on sepiolite. The analytical results showed that CeO 2 /SEP had good crystallization, and CeO 2 nanoparticles were deposited on the surface of fibrous sepiolite. The composite photocatalyst with 50 % CeO 2 loading presented the highest tetracycline degradation efficiency (92.7 %), and the reaction rate constant was 4.88 times greater than that of pure CeO 2. In addition, quenching experiments showed that the main reactive active species included photogenerated holes (h+) and superoxide radical anions(O 2 ·-).Furthermore, the enhanced photodegradation mechanisms and the possible degradation pathways of TC were also systematically discussed. The investigating results show that the enhanced photocatalytic performance was mainly due to the uniform attachment of CeO 2 with smaller particle size on the surface of sepiolite, which increased the specific surface area of the photocatalyst and promoted the redox cycle of Ce3+/Ce4+ to generate more reactive free radicals. It can be concluded that this study offers a new potential option for efficient photodegradation of antibiotics in wastewater based on the visible-light-driven mineral based photocatalyst. [Display omitted] • CeO 2 /sepiolite photocatalyst was successfully synthesized by the precipitation method. • CeO 2 /sepiolite exhibited outstanding TC degradation performance under visble light. • h+ and O 2 ·- were the main active species during TC degradation process. [ABSTRACT FROM AUTHOR]

In this study, a high molecular weight arabinoxylan (AX, Mw: 694 kDa) from wheat bran was alkaline extracted and covalently linked with Catechin (CA) by free radical catalytic reaction. Comparing to AX, arabinoxylan-catechin (AX-CA) conjugates demonstrated an extra UV–vis absorption peak at 274 nm, a new FT-IR absorption band at 1516 cm−1 and new proton signals at 6.5–7.5 ppm, which all confirmed the covalently linked structure. Grafting CA onto AX not only decreased the molecular weight, thermal stability and apparent viscosity of AX, but also enhanced its inhibition effects on starch digestibility in vitro. The in vitro fermentation test with pig feces showed that the degradation & utilization rate of AX, the total short-chain fatty acid (SCFA) and acetic acid levels produced all were significantly delayed after grafting. This study provided a novel approach to synthesize AX-CA conjugates that could be a novel dietary fiber of enhanced functional/bioactive properties using in the fields of functional foods and medicine. [ABSTRACT FROM AUTHOR]

In this study, AlCo-LDH/sepiolite composite catalysts were successfully prepared by a simple water bath method. In the AlCo-LDH/sepiolite composite catalyst, the nanosheet structure of LDH was uniformly immobilized on the surface of sepiolite fibers. The AlCo-LDH/sepiolite composite catalyst was proposed to activate peroxymonosulfate (PMS) to remove norfloxacin (NOR). The reaction rate constant for the degradation of NOR was investigated to be 0.3405 min−1 in the AlCo-LDH/sepiolite/PMS system, which was 2.22 times higher than that of the AlCo-LDH/PMS system. The combination of AlCo-LDH with sepiolite carriers increased the specific surface area of the catalysts, exposing more active sites and widening the distribution of surface hydroxyl groups, which resulted in a significant enhancement of the combination of AlCo-LDH with sepiolite/PMS significantly improved the degradation performance of NOR. Quenching experiments revealed that SO 4 •- and 1O 2 played the main roles in the degradation of NOR, with both radical and non-radical pathways contributing, and the Co(III)/Co(II) redox cycle was found to be crucial for the activation of PMS to degrade NOR efficiently. In addition, the reaction mechanism and degradation pathway of NOR degradation in this system were elucidated. In conclusion, the AlCo-LDH/sepiolite composites provide a new reference for the development of environmentally friendly catalysts, and have good application prospects in activating PMS for wastewater treatment. [Display omitted] • AlCo-LDH/sepiolite catalysts were successfully synthesized by water bath method. • AlCo-LDH/sepiolite/PMS system exhibited outstanding NOR degradation performance. • SO 4 •- and 1O 2 were the main active species in NOR degradation reaction process. [ABSTRACT FROM AUTHOR]

The application of Streptococcus thermophilus S-3 into yogurt production was studied and the structural properties of the generated exopolysaccharides (EPS-S3) were characterized. The proposed structure of EPS-S3 was obtained. EPS-S3 contained a high ratio of N-Acetyl-galactosamine with the Mw of 574 kDa, which was higher than that of AR333 (314 kD) leading to higher apparent viscosity. Streptococcus thermophilus strain S-3 was co-cultured with Lactobacillus delbrueckii for yogut production which highly increased the acidifying rate and post-acidification rate. The quality of the co-cultured yogurts in terms of apparent viscosity, syneresis capacity, water holding capacity and rheological properties were much better than that by using Lactobacillus bulgaricus only. The production mechanism of EPS-S3 from gene regulated level was also discussed which is helpful to facilitate the application of Streptococcus thermophilus strain into milk production. [ABSTRACT FROM AUTHOR]

A high Mw (5012 kDa) polysaccharide (PNPS) from the fruiting body of Pleurotus nebrodensis was isolated using water extraction followed by ethanol precipitation. The structural characteristics and in vitro fermentation behaviors of this polysaccharide was investigated. Chemical composition analysis showed the total sugar content of PNPS was up to 97.20 ± 1.80 wt%. Monosaccharide composition analysis showed PNPS contained mainly glucose (89.22 ± 5.70 mol%) while small percentage of mannose (5.60 ± 0.74 mol%) and galactose (5.18 ± 0.33 mol%) were also detected. According to the linkage pattern analysis (methylation analysis), PNPS comprised mainly 4-β-D-Glc p (58.90 mol%), while other residues including α-D-Glc p , 6-α-D-Gal p , 3,6-α-D-Man p , 3-β-D-Glc p and 6-α-D-Glc p were detected with a comparable amount. Combined with results from 1D and 2D NMR spectrum, a proposed structure of PNPS was presented. In vitro fermentation of PNPS by gut microbiota showed total SCFA production of all treatment groups was higher than negative control group (NC) significantly (p < 0.05) after 48 h of fermentation. The formation of SCFAs was mainly acetic acid, followed by propionic acid and butyric acid, and the pH was decreased from 6.95 to 4.70. After 72 h, the total sugar content decreased from 5.813 ± 0.87 mg/L to 0.23 ± 0.065 mg/L, and the molecular weight of PNPS decreased. • The structure of Pleurotus nebrodensis polysaccharide was analyzed. • The in vitro fermentation characteristics of Pleurotus nebrodensis polysaccharide were studied for the first time. • The structure-activity relationships of Pleurotus nebrodensis polysaccharide were explored. [ABSTRACT FROM AUTHOR]

In this study, Fe 3 O 4 /sepiolite composites as peroxymonosulfate (PMS) catalysts were successfully synthesized via a simple water bath method for tetracycline (TC) degradation. The results indicated that the composite with 70% Fe 3 O 4 loading amount exhibited the highest TC degradation efficiency (90.12%), and its reaction rate constant (0.02193 min−1) was around 2.07 times higher than that of pure Fe 3 O 4. The enhanced catalytic activity was mainly attributed to the uniform deposition of Fe 3 O 4 nanoparticles with smaller grain size (17.24 nm) on sepiolite, leading to the larger specific surface area (120.61 m2/g) and more exposed reaction active sites. The electron paramagnetic resonance (EPR) and quenching experiments displayed that 1O 2 species played the predominant roles in TC degradation process. Besides, potential catalytic mechanisms and degradation pathways of TC were proposed. The toxicity of TC was reduced during the degradation process. Overall, this work can provide a new strategy for the rational design of promising mineral-based PMS catalyst for the wastewater treatment. [Display omitted] • Fe 3 O 4 /sepiolite as PMS catalyst was synthesized via a simple water bath method. • The Fe 3 O 4 /sepiolite exhibited outstanding tetracycline degradation performance. • The potential mechanism of TC degradation and the toxicity of byproduct were studied. [ABSTRACT FROM AUTHOR]

Corn bran hemicellulose was extracted from de-oiled and de-starched corn bran using 0.3 M alkali at 120 °C. Following neutralization, ethanol (75%) precipitation, dialysis, protein digestion, re-precipitation in ethanol, and freeze-drying, purified corn fiber gum (PCFG) was obtained in overall yield of 45.96%. PCFG gave a single peak by high performance size exclusion chromatograph, and had average molecular weight of 296 kDa. Monosaccharide composition, methylation, and GC–MS analysis indicated that PCFG was comprised of three monosaccharides, arabinose (ara f), xylose (xyl p) and galactose (gal p) with the following linkage: t-ara f , 17.09%; 1,3-ara f , 12.43%; t-xyl p , 16.13%; 1,4-xyl p , 11.57%; 1,3,4-xyl p , 26.02%; 1,2,3,4-xyl p , 10.46%; t-gal p , 6.37%. Partial acid hydrolysis suggested that arabinofuranose sugar residues were substituted onto a 1,4-linked xylan backbone. Extensive 1D and 2D NMR spectroscopy was used to identify and confirm the following linkages: t-xyl p , 1,2,3,4-β-D-xyl p, t-α-L-ara f , 1,2-α-L-ara f and 1,4-β-D-xyl p. Several other linkage fragments were also deduced: t-ara f →2-ara f →2- O -(1,3,4-xyl), t-ara f →2-ara f →3- O -(1,2,4-xyl), t-ara f →2-ara f →3-ara f, and t-gal→2-ara. Image 1 • Purified corn fibre gum (PCFG) was extracted from corn bran. • Major monosaccharides in PCFG were arabinose, xylose, and galactose. • Glyosidic linkages in PCFG were identified by NMR and methylation analysis. • Monosaccharide sequence was determined by partial hydrolysis and NMR. [ABSTRACT FROM AUTHOR]

Abstract The fruit of hawthorn (Crataegus pinnatifida Bge. var. major) is rich in pectic polysaccharides and has been used for centuries in China as food and herb. Hawthorn pectin (HP) recently has attracted rising attention due to the reported functional properties (e.g. gelling, emulsification) and health benefits towards the cardiovascular system. In this study, using hawthorn wine residue as raw material, a high methoxylated pectic polysaccharide HSP (degree of esterification up to 70%) was obtained by mild acid extraction (yield up to 20 wt%). Results from HPSEC coupled with triple detector revealed a widely dispersed (polydispersity index = 2) pectic polysaccharide with weight average molecular weight (Mw) of 111.7 kDa. Compared to pectin extracted from the hawthorn fruit, HSP showed a relatively lower molecular weight and higher polydispersity index (PDI), which suggested that the degradation of HP molecular chain during the wine-making processing (fermentation). Functionally, HSP demonstrated relatively high apparent viscosity but did not form gel in aqueous solution at concentrations up to 8 wt%. Structurally, HSP molecule was composed of over 70 mol% of 4-Gal p A, with a small amount of glucose, galactose, xylose and arabinose. Under pectinase hydrolysis, over 95 wt% of the HSP was degraded into small fragments and monosaccharides; a small portion of relatively higher molecular weight rhamnose rich fragments were obtained from the hydrolytes. Combining both methylation analysis and 1D NMR spectroscopy, structural features of HSP were partially elucidated. Graphical abstract Image 1 Highlights • A high methoxylated pectic polysaccharide was extracted from hawthorn wine residue. • Physicochemical, functional and partial structural features were investigated. • Molecular degradation of pectin took place during wine-making process. • Pectin showed relatively high apparent viscosity but did not form gel. • Pectin contained mainly HG, but small portion of RG-I and RG-II were also detected. [ABSTRACT FROM AUTHOR]

• Measure the energy and environmental performance of 260 cities in China. • Use China's smart city pilot policy as a quasi-natural experiment. • Evaluate the effect of smart city construction on energy and environmental performance. • Smart city construction has two important influence channels. Attaining a win-win scenario among economic growth, energy conservation, and emission reduction is an essential requirement for the transformation towards smart cities. This research leverages panel data from 260 prefecture-level cities in China between 2009 and 2020, applies the non-radial directional distance function (NDDF) for the quantification of energy and environmental performance (EEP), and harnesses the multi-period difference-in-differences (DID) model to empirically investigate the influence of the smart city pilot policy (SCPP) on EEP. The findings reveal the following. (1) SCPP significantly enhances EEP in cities of China. (2) Mechanism analysis indicates that SCPP primarily improves EEP by promoting economic agglomeration and driving innovation development. (3) The enhancement effect of SCPP on EEP exhibits a time lag and tends to decay in later stages, without exerting a notable spillover effect on EEP of neighboring cities. (4) The EEP of cities with lower administrative levels and insufficient resource endowments has experienced more substantial improvements under SCPP. This study offers valuable insights for developing countries with backgrounds similar to China for improving urban ecological environments and achieving sustainable development. [Display omitted] [ABSTRACT FROM AUTHOR]

Yogurt fermented by Streptococcus thermophiles S-3 strain showed higher viscosity and thicker mouth feel than the ones using other lactic acid bacteria strains, which was due to the higher yield of exopolysaccharide (EPS-3) produced during fermentation process. In the present study, molecular characteristics, partial structural features and rheological properties of EPS-3 were studied using triple-detector HPSEC, NMR and steady & dynamic rheological testing, respectively. EPS-3 showed relatively high molecular weight (574 kDa) and narrow polydispersity Index (1.27). Monosaccharides composition analysis indicated that EPS-3 was composed of N-Acetyl-galactosamine, galactose and glucose in the molar ratio of 1:2:1. Conformational parameters from Mark-Houwink equation (0.68) and R g & M w relationships (0.56) both indicated a random coil conformation of EPS-3. Results from steady flow tests showed an obvious shear thinning behavior, which was enhanced with the increased concentrations and decreased temperatures. Dynamic rheology indicated that EPS-3 was reluctant to form gel in water solution (G” > G'). EPS-3 demonstrated compatible interaction with milk protein with less syneresis in comparison to the yogurts adding agar and/or pectin. With all the information provided, this study could help promote the application of both EPS-3 and S. thermophiles S-3 strain in different dairy products. [ABSTRACT FROM AUTHOR]

Hemicellulose fraction from dried distillers grains with solubles (DDGS) was isolated and its molecular structural and conformational properties were elucidated by using partial acid hydrolysis, methylation analysis and NMR spectroscopy. Using 0.3 M sodium hydroxide (120 °C), a purified water soluble hemicellulose molecules (HFG) was isolated from de-oiled and de-starched DDGS. The yield of HFG was up to 27% (w/w). Results from monosaccharide composition, methylation analysis indicated that HFG comprised three types of sugar residues: arabinose based sugar residues including t-Ara f (28.6 mol%) and 1,3-Ara f (4.9 mol%); xylose based sugar residues including t-Xyl p (14.1 mol%), 1,4-Xyl p (18.6 mol%), 1,3, 4-Xyl p (20.8 mol%), and 1,2,3,4-Xyl p (6.8 mol%); and galactose based sugar residue including t-Gal p (6.1 mol%). Partial acid hydrolysis combined with high performance size exclusion chromatography (HPSEC) indicated that protein (4.69%) was covalently linked with carbohydrate portion in HFG, which can be potentially used as food emulsifiers. Although HFG had a high substitution degree (75%), it was a more rigid molecule compare to gum arabic, indicating a shorter branching chain of HFG. 1D and 2D NMR spectroscopy confirmed the presence of t-xyl p , 2,3,4-β-D-xyl p, t-α-L-ara f , 3-α-L-ara f and 4-β-D-xyl p and several linkage fragments were deduced: t-ara f →2-ara f →2- O -(1,2,3,4-xyl), t-ara f →2-ara f →3- O -(1,2,3,4-xyl), t-ara f →2-ara f →3-ara f and t-gal→2-ara. The information gained from this study could help us to better understand the properties of hemicellulose and its performance in applications. [ABSTRACT FROM AUTHOR]

• Energy use positively affects carbon emission intensity. • Urbanization has positive impact on carbon emission intensity. • Technological innovation negatively affects carbon emission intensity. • Data was analyzed by Quantile-on-quantile model. In recent years, policy experts have engaged in a spirited discussion over the relationship between environmental quality and energy use. This association is critical for the mitigation of climate change and achieving Sustainable Development Goals (SDGs). Furthermore, current studies have not given enough consideration to this relation, notably in the case of the Kingdom of Saudi Arabia (KSA). Therefore, this study examines the KSA case, focuses on the connection of industrialization, foreign direct investments, and technological innovation with carbon emissions intensity (CEI) by also considering urbanization and energy use, examines the period between 1991 and 2020, and uses quantile-on-quantile (QQ) regressionand quantile regression (QR) approaches for empirical examination. The empirical outcomes revealthat (i) urbanization and energy usehave an increasing impact on CEIin all quantiles; (ii) industrialization, foreign direct investments, and technological innovation have a generally decreasing impact on the CEI in most quantiles; (iii) power of the factors' impact on the CEI change according to quantiles; (iv) the robustness the findings is also validated. Hence, theresults highlight the importance of quantile-based analysis and suggest that KSA authorities need to embrace environment-friendly policies while managing environmental pollution to develop industrialization level and technological innovation as well as increase foreign direct investments. [ABSTRACT FROM AUTHOR]

LCP1, a high molecular weight fraction of the EPSs produced by strain LC2W isolated from skim milk, was studied by partial acid hydrolysis, smith degradation, methylation analysis and 1D & 2D NMR spectroscopy to elucidate its main structure feature. Monosaccharides composition analysis revealed the presence of glucose (57.8% mol%), rhamnose (27.7%, mol%) and galactose (14.5%, mol%), respectively. O-acetyl (–OAc) and N-acetyl (–NAc) groups were also evidenced by FTIR and NMR spectroscopies. The linkage patterns of sugar residues were determined by methylation analysis and partial acid hydrolysis. The main sugar residues included: T-Rhm p (18.4%), 3-Rhm p (15.7%) T-Glc p (21.7), 4-Glc p (16.3%), 3,4,6-Glc p (16.3%) and 2,6-Gal p (11.9%). 1D and 2D NMR analysis revealed that both –OAc and –NAc were connected to 3-Rhm p at O-2 position. The configuration and glycosidic sequences for sugar residues were established by 2D NMR spectroscopy. A possible structure of LCP1 was proposed. [ABSTRACT FROM AUTHOR]

The structure and conformation relationships of a heteropolysaccharide (Glc p A)Xylan in terms of various molecular weights, Xyl p /Glc p A ratio and the distribution of Glc p A along xylan chain were investigated using computer modeling. The adiabatic contour maps of xylobiose, Xyl p Xyl p (Glc p A) and (Glc p A)Xyl p Xyl p (Glc p A) indicated that the insertion of the side group (Glc p A) influenced the accessible conformational space of xylobiose molecule. RIS-Metropolis Monte Carlo method indicated that insertion of Glc p A side chain induced a lowering effect of the calculated chain extension at low Glc p A:Xyl p ratio (Glc p A:Xyl p = 1:3). The chain, however, became extended when the ratio of Glc p A:Xyl p above 2/3. It was also shown that the spatial extension of the polymer chains was dependent on the distribution of side chain: the random distribution demonstrated the most flexible structure compared to block and alternative distribution. The present studies provide a unique insight into the dependence of both side chain ratio and distribution on the stiffness and flexibility of various (Glc p A)Xylan molecules. [ABSTRACT FROM AUTHOR]

In the setting of Digital China, the smart city pilot strategy has become a fundamental part of the intelligent upgrading of the urban development model. Exploring the influence of smart city pilot policies on urban innovation performance is critical for achieving high-quality economic development and creating an innovation-driven country. This study views the experimental smart city policy in China as a quasi-natural experiment and assesses the improved influence of smart city development on urban innovation performance by constructing a multiple period difference-in-differences (DID) model, then confirms it using a variety of robustness test methodologies. The results show that urban innovation performance benefits from the construction of smart cities, and the promotion effect is sustainable. The level of economic development and information infrastructure, as well as the financial innovation expenditure, have a beneficial effect in encouraging smart city construction innovation performance, while the degree of opening-up hinders the improvement of smart city urban innovation performance. In addition, it is also found that there is heterogeneity in the promotion effect of smart city building on urban innovation performance. The research of this paper provides useful enlightenment for better exerting the promotion effect of smart city building on urban innovation performance. • Smart city construction positively promotes urban innovation performance. • There indeed exists economic region and city size heterogeneity of the positive effect. • The influencing factors of smart city innovation performance are discussed. • The multiple period difference-in-differences (DID) model was adopted. [ABSTRACT FROM AUTHOR]

In this paper, δ-MnO 2 and Fe/δ-MnO 2 -X (X = 0, 1, 2 and 5) nanomaterials were prepared by a one-step water bath co-precipitation method, and then their performance in catalytic oxidation of HCHO at room temperature was investigated. The catalytic oxidation performance of Fe/δ-MnO 2 -5 nanomaterials for formaldehyde was significantly improved by the modification with iron doping and sulfuric acid, and the conversion of 3.35 ppm HCHO reached 99.4% within 8 h at room temperature. Next, the nanomaterials were characterized by X-ray diffraction (XRD), spectroscopy scanning electron microscope (SEM), High-resolution transmission electron microscopy (HR-TEM)，Brunauer-Emmett-Teller (BET), temperature-programmed reduction by H 2 (H 2 -TPR), X-ray photoelectron spectroscopy (XPS) methods to investigate the structural properties of the nanomaterials. It was found that the specific surface area of the composite nanomaterials increased, the particle distribution was more uniform, and the distribution of Mn on the catalyst surface changed significantly. Among them, the content of Mn3+ increased significantly, which was beneficial to the catalytic oxidation of formaldehyde. [Display omitted] • One-step method prepared Fe/δ-MnO 2 -X (X = 0, 1, 2 and 5) nanomaterials. • The doping of ferrous ion is beneficial to the conversion of Mn2+and Mn4+ to Mn3+. • After modification, lattice defects on the surface of δ-MnO 2. • Mn3+ plays a decisive role in the catalytic oxidation of formaldehyde. [ABSTRACT FROM AUTHOR]

The conflict between cultivated land protection and economic development has become increasingly acute in recent years. Despite, intensive researches made on this conflict, little attention has been paid to the spatial correlation of variables. In view of this, the paper introduces the spatial panel regression model to estimate, and test whether the relationship between economic growth and cultivated land conversion conforms to Kuznets curve. Research results show that the area of converted cultivated land in China exhibits strong spatial auto-correlation; the spatial panel model with time effect and fixed effect is more stable and significant than conventional panel mode, and that the relationship between economic growth and cultivated land conversion agrees with the inverted U-shape of Kuznets curve, with inflection point occurring when average per capita GDP reaches ¥31330.93 (calculated at comparable price of 1999). On the basis of analysis, it is suggested that the government, with a view to developing economy alongside protecting cultivated land, should attach more importance to land use and planning in the future, pay more attention to the spatial correlation of cultivated land planning in adjacent areas and make greater efforts to increase the input–output ratio of land. [ABSTRACT FROM AUTHOR]

Gum ghatti has been shown to possess excellent emulsification properties because of its proteinaceous components. Here we use TFA and TFMS hydrolysis to investigate the nature of this protein, and characterize it using HPLC-ESI-MS/MS. The following nine peptide fragments were sequenced by HPLC-ESI-MS/MS analysis: MLPVLEHELVPAR, LLNTLEGNEFK, LKAYGSATCLR, LAGLVVR, MTPASLSHVK, YTVRGNRNVVR, HGPVLNK, NPNALTK, and CKKEVK. The hydrophobic scores of the main peptide fragments from gum ghatti (566) were higher than those of gum arabic (241). The hydrophobic amino acid distribution in gum ghatti is similar to that in β-casein; both have hydrophobic amino acid sequences which can provide a strong oil binding capacity at the interface between the oil and water. [ABSTRACT FROM AUTHOR]

Non-starch polysaccharides (GSP) from roots of American ginseng were extracted and purified. The physicochemical properties and detailed structure of GSP was systematically studied using high performance size-exclusion chromatography (HPSEC), Fourier transform infrared spectroscopy (FTIR), methylation analysis and 1D & 2D NMR spectroscopy. Weight average molecular weight (Mw) and intrinsic viscosity of GSP was 85.4 kDa and 0.41 dL/g, respectively. Monosaccharide composition analysis indicated that GSP consisted of rhamnose, arabinose, galactose, glucose and uronic acid with a weight ratio of 1:4:8:8:50. The dominate component in GSP was galacturonic acid (up to 70% in molar ratio) based on methylation analysis. FTIR demonstrated that GSP had pectin based structure and the degree of esterification (DE) was calculated to be 38%. Based on 1D & 2D NMR spectroscopy, the major sugar residue of GSP molecule was 4-α-D-Gal p A, other residues including 2-α-L-Rha p , 2,4-α-L-Rha p , α-L-Ara f , β-D-Gal p , 4-β-D-Gal p were also evidenced in GSP. As a pectin molecule, GSP contained mainly homogalacturonans structure, while a small portion of rhamnogalacturonan I character was also identified. [ABSTRACT FROM AUTHOR]

The conformational properties of gum ghatti and its fractions were investigated using high performance size exclusion chromatography (HPSEC) coupled with multiple detectors, static light scattering (SLS) and dynamic light scattering (DLS) methods. The measured Mark–Houwink equation parameters α (0.5 < α < 0.8) indicated a random coil conformation of four fractions: F50 was more rigid than the other fractions, whereas F65 exhibited a loosely extended chain that is close to a spherical conformation. DLS and SLS measurements in aggregate free (0.5 M NaOH) solution further confirmed the conformational properties. The high positive A 2 value of each fraction indicated that 0.5 M NaOH solution is a good solvent for gum ghatti. The values of R g and R h decreased with molecular weight in the order of F80, F65 and F50. The less branched fraction F50 ( ρ = 1.694) has a random coil conformation in 0.5 M NaOH solution, whereas F65 and F80 exhibited random coil close to spherical conformation due to their highly branched structure. [ABSTRACT FROM AUTHOR]

This paper is based on a series of physical and chemical investigations to understand the structure–function properties of gum ghatti. After elucidating the detailed molecular structure of two gum ghatti fractions, the structure of its component glycoprotein was investigated whereby, the protein sequence and hydrophobicity were identified, followed by the conformational analysis of the gum and its fractions. Many techniques were used for the elucidation of the fine structures, which included methylation analysis-GC-MS, Maldi-TOF MS and 2D NMR spectroscopy, homonuclear 1 H/ 1 H correlations spectroscopy (COSY, TOCSY), heteronuclear 13 C/ 1 H multiple-quantum coherence spectroscopy (HMQC) and heteronuclear multiple bond correlation (HMBC). Conformational properties were studied using a modeling system (Insight II) to relate the hydrophobicity of the protein moieties with the complex structures of the carbohydrates. These studies now provide an explanation for the excellent emulsification properties of gum ghatti in oil-in-water emulsions, which enable its application in the food, cosmetic and/or pharmaceutical industries. [ABSTRACT FROM AUTHOR]

• Measured the carbon emissions of 231 cities in China. • Evaluated the effect of smart city construction on emission reduction. • Evaluated the effect of smart city construction on energy saving. • Energy efficiency is the mechanism for the construction of smart city to reduce emissions. Developing countries constantly face the predicament of how to achieve the common progress of economic growth and environmental protection, and smart city construction may be the key. This study takes a smart city pilot policy in China as the starting point, and systematically evaluates the effects of smart city construction on energy saving and CO 2 emission reduction using a progressive difference-in-differences method. The research conclusions show that: 1. Smart city construction has significantly reduced per capita CO 2 emissions, with a reduction effect of approximately 18.42 logarithmic percentage points. This conclusion remains valid in the placebo test, instrumental variable method, and a series of robustness verifications. 2. There is an inverted U-shaped relationship between energy efficiency and per capita CO 2 emissions, and most cities in China have crossed the inflection point; smart city construction achieves energy savings and reduces per capita CO 2 emissions by improving energy efficiency. 3. The effect of smart city construction on CO 2 emission reduction is more obvious in cities with higher administrative levels, higher levels of neutral technological progress and green innovation, and higher levels of advanced industrial structure. This research provides an empirical basis for how developing countries or regions can move toward sustainable development through digital and intelligent transformation and demonstrates the importance of providing new infrastructure construction such as smart cities from the perspective of a low-carbon economy. [ABSTRACT FROM AUTHOR]

Abstract: The conformational properties of a high molecular weight polysaccharide (60P) extracted from Artemisia sphaerocephala Krasch (ASK) were investigated. The M w and R g of 60P were obtained using both static light scattering and HPSEC techniques, which were 590 kDa and 56 nm, respectively. Dynamic light scattering measurement indicated that 0.5 M NaOH solvents exhibited the ability to reduce/eliminate aggregates of 60P. 60P in 0.5 M NaOH showed strong concentration dependence, but minimal angular dependence. The average structure parameter ρ (R g/R h) value of 1.75 indicated that 60P exhibited a random coil conformation in 0.5 M NaOH solution. The conformational parameters (derived from R g vs M w and R h vs M w) from HPSEC also suggested a random coil conformation of 60P in 0.1 M NaNO3 solution (eluent for HPSEC). The characteristic ratio and the persistence length obtained from the random flight model and wormlike cylinder model both indicated a semi-flexible structure of 60P. [Copyright &y& Elsevier]

Abstract: Using 60% (w/v) ammonium sulfate precipitation, a heteropolysaccharide (designated 60S), with relatively low molecular weight (38.7kDa), was isolated from the seeds of Artemisia sphaerocephala Krasch. The structural properties of 60S were elucidated by partial acid hydrolysis, methylation analysis, 1D and 2D NMR spectroscopy, and MALDI-TOF-MS. The results of the partial acid hydrolysis and methylation analysis indicated that the main chain of 60S consisted of (1→4)-linked d-Manp and (1→4)-linked d-Glcp in a molar ratio of 1:1.3. Over half of the glucosyl residues in the main chain were branched at the O-6 position. The terminal sugar residues were mainly composed of T-Araf, T-Arap, T-Galp, T-GlcpA, and T-Glcp. Besides, 3-Araf and 2-Galp were also observed in comparable amounts. Based on all the aforementioned results and the data obtained by 1D and 2D NMR spectroscopy as well as MALDI-TOF-MS, a structure of 60S is proposed as follows: ▪ R could be one or some of -(3-α-Araf) n -(A), T-α-Galp (B), T-α-Glcp (C), T-Araf (H) or T-Arap. [Copyright &y& Elsevier]

Abstract: The extraction and fractionation methods as well as the physicochemical properties of Artemisia sphaerocephala Krasch polysaccharide (ASKP) were studied. ASKP was extracted from the outer layer of the seeds with high ratio of hot water to seeds (400:1, v/w). The yield of water-soluble ASKP was 13.6% (w/w). High performance size exclusion chromatography (HPSEC) results indicated that ASKP had two components with different molecular weights. The high molecular weight (Mw, 551.3KDa) fraction 60P was separated from the low molecular weight fraction 60S (Mw, 38.7KDa) by precipitation in 60% (w/v) ammonium sulfate salt solution. Steady flow rheological tests revealed that the apparent viscosity of 1.5% (w/v) ASKP decreased logarithmically with the increasing temperature. Small strain oscillation tests suggested that 4% (w/v) 60P solution was a typical viscous fluid. ASKP was composed of 66.9% (w/w) neutral sugar and 15.8% (w/w) uronic acid; 60P comprised of 55.4% (w/w) neutral sugar and 25.8% (w/w) uronic acid, while in 60S, the percentage of neutral sugar and uronic acid were 87.1% and 10.4%, respectively. Relative monosaccharide composition analysis showed that 60S was composed of 38.3% glucose, 28.1% mannose, 24.2% galactose and 9.4% arabinose, while the 60P fraction contained 80.5% xylose, 10.9% arabinose, 5.0% glucose, 2.3% galactose and 1.2% rhamnose. 60S exhibited the highest surface activity compared to ASKP, 60P, ASKPE (ASKP with protein removed) and 60PE (60P with protein removed) although no protein was detected in this fraction. [Copyright &y& Elsevier]

Abstract: The structure of a high molecular weight heteropolysaccharide (60P) isolated from Artemisia sphaerocephala Krasch was elucidated using methylation analysis and 2D NMR spectroscopy. 60P (Mw: 551kDa) was isolated from A. sphaerocephala Krasch (ASK) seeds, using hot water extraction and ammonium sulphate salt precipitation. Methylation and GC–MS analysis indicated that 60P was mainly composed of three types of sugar residues: 4-Xylp (27.8%), 2,4-Xylp (26.0%) and T-GlcpA (22.5%); small amount of 4-GalpA, 4-Glcp, T-Araf, T-Arap and 4, 6-GalpA were also detected with comparable molar ratio. Based on the results of monosaccharide composition, methylation analysis and NMR spectroscopy, a proposed structure is shown below: Display Omitted R represents one of the following groups: T-Araf, T-Arap, T-Araf →3-Araf (1→ and T-Arap →3-Araf (1→. [Copyright &y& Elsevier]

The willingness of migrating due to air pollution is widespread in China. However, there is a lack of direct evidence and discussion regarding whether this willingness has been translated into action. In this study, PM2.5 concentrations were used to represent air pollution in each city and were compared with individual migration data from the China Labor-force Dynamics Survey (CLDS) to examine population migration effects caused by air pollution. This study showed that (1) Population migration between Chinese cities shows sensitivity to air pollution, and air pollution increases the probability of moving away for local population. This finding is held under multiple robustness and endogeneity tests. (2) Population migration effects caused by air pollution were more pronounced among women, middle-aged people, those with lower educational levels, from agricultural households, Han Chinese groups, and populations in southern cities. (3) The use of individual self-rated health data verified that physical health is an important channel through which individual migration decisions are influenced by air pollution, the older an individual, the more his or her health was affected. In light of these findings, this study led to conclusions regarding targeted policy recommendations in terms of talent clustering, social equity, and demographic balance. [ABSTRACT FROM AUTHOR]

Flaxseed gums (FG) previously reported were mostly isolated from hulls and seeds under a relatively low temperature, which led to an incomplete structural and functional understanding of the entire gum. In addition, the influences of processing conditions on the functional properties of FG have rarely been studied. In this study, FG was extracted by water at high temperature (90 °C) followed by ethanol precipitation. The physicochemical characteristics of the high temperature extracted FG were investigated, including its rheological and emulsion stabilizing properties in aqueous solution. The influences of homogenization and heating-cooling treatments on the functional properties of FG were also examined. Results indicated that FG could form a gel in aqueous solution (>0.5 wt%) at room temperature (25 °C). Mechanical shearing forces derived from homogenization (50 MPa) highly decreased the elastic properties of FG by disrupting the intermolecular network. However, the disrupted network could not be recovered by reheating (85 °C) and cooling (25 °C) processes indicating it was non-reversible. It was also observed that FG of 0.4 wt% demonstrated the best stabilizing effect on the oil/water emulsion systems for the appropriate viscosity and weak-gel properties. The study aims to provide a full understanding of the rheological and emulsifying properties of high temperature extracted FG under different treating conditions with an intent to promote its application in the food and non-food industries. Image 1 • Rheological properties of FG solution were systematically studied. • The gelling ability of FG solution increased with increasing concentration. • The viscoelasticity of FG solution decreased with increasing temperature. • The destroyed FG network could not be recovered after heating-cooling treatment. • FG of 0.4 wt% demonstrated best stabilizing effect against oil/water emulsion. [ABSTRACT FROM AUTHOR]

Haze has seriously threatened the ecological environment and public health, so researching environmental efficiency under haze constraints is significant in managing pollution and evaluating the balance between economic development and environmental health. Based on the panel data of China's 99 cities during 2005–2017, this paper uses α-convergence and β-convergence models to analyze the spatial convergence of environmental efficiency under haze constraints and its drivers in China,specifically in Eastern China, Central China, and Western China.The main results are as follows: (1) The trend of environmental efficiency under haze constraints in these regions evidently follows a dumbbell curve. In recent years, it has been growing slowly in Eastern China, Central China, and Western China, and the environmental efficiency in the Eastern China is the highest, the Central China is the second, and the Western China is the lowest; (2) it demonstrates both α-convergence and β-convergence in Central China, Western China, and Eastern China, and the speed of convergence is the fastest in the Central China, the second in the Western China and the slowest in the Eastern China; there is a "catch-up effect" in cities from less environmentally efficient regions to more efficient regions; and (3) Industrial structure and degree of trade dependence have a significantly negative correlation; characteristics of the region and dependence on foreign investment have significantly positive correlations with the environmental efficiency of Eastern China and Central China; environmental regulations and economic scale limit the improvement of environmental efficiency of Central China and Western China; and technological innovation significantly impacts Eastern China only. Although the paper refers to the specific evidence of China, with haze as a new indicator in the comprehensive evaluation of environmental efficiency can be extended to other developing countries as well as to other pollutants such as land pollution and waste water. The understanding of drivers of environmental efficiency under haze constraints in China provides international policy-makers with valuable reference for formulating effective measures to balance the dilemma between economic development and environmental health. • Haze was brought into the framework of environmental efficiency. • The environmental efficiency in China followed a dumbbell curve. • A "catch-up effect" in less environmentally efficient regions was confirmed. • Industrial structure had a negative correlation with the environmental efficiency [ABSTRACT FROM AUTHOR]

• Composition and nutritional value of white and green asparagus are compared. • The bioactive compounds of asparagus and their health benefits are summarised. • The processing properties of asparagus are discussed. • Asparagus related patents are herein listed. Asparagus (Asparagus officinalis L.) is a perennial herb with various bioactivities and has been widely used as medicine and food since ancient times. With the reputation of "the king of vegetables" in the international market, its health benefits and biological functions have attracted increasing interests from both public and academia. This review summarizes the nutritional values, bioactive compounds, biological functions and the food and non-food applications of asparagus. Moreover, the relationships between health benefits and its bioactive components are also discussed. Asparagus contains various phytochemical compounds such as polysaccharides, polyphenols, anthocyanins and saponins, which exhibit anti-cancer, anti-tumor, antioxidant, immunomodulatory, hypoglycemic, anti-hypertensive and anti-epileptic effects through in vitro and in vivo experiments. However, it is critical to bridge the gap between bioactive components and human health and to uncover their corresponding mechanisms. This paper will help to facilitate the food and medicinal application of Asparagus in the future. [ABSTRACT FROM AUTHOR]