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[Display omitted] • The La based nanorod support was synthesized by the hydrothermal method. • The Ni-based supported catalysts were prepared by various methods. • The effects of support morphology and preparation method were studied. • The rod-shaped catalyst prepared by the deposition–precipitation method was the best. • The reaction mechanism of CO 2 methanation was investigated by the in-situ techniques. In this work, the La(OH) 3 nanorods were successfully synthesized by precisely regulating the parameters of the hydrothermal method. Then, a series of Ni-based CO 2 methanation catalysts were fabricated via the incipient-wetness impregnation and deposition–precipitation methods by employing the La(OH) 3 nanorods as the supports. The influences of the support morphology and the preparation method on the metal-support interaction, Ni dispersion, and the surface basicity were carefully investigated based on various techniques, such as XRD, SEM, H 2 -TPR, CO 2 -TPD, XPS, ect. It was found that the rod-shaped La(OH) 3 supported catalyst prepared by the deposition–precipitation method performed the optimum activity and stability. The reason for this could be derived from the confinement effect of the crystal plane of the rod-shaped support, which would promote the formation of the strong metal-support interaction and the construction of the Ni-La interface with high activity. Furthermore, the online-tandem TG-MS and in-situ DRIFTS technologies were used to investigate the thermal decomposition performance of the catalyst precursors in the calcination process and the reaction intermediates of the CO 2 methanation. Therefore, the fundamental roles of support morphology and catalyst preparation method were expected to direct the advancement of the Ni-based nanostructured catalysts with outstanding low-temperature performances. [ABSTRACT FROM AUTHOR]

Phosphorus (P) is a nonrenewable resource and a critical element for plant growth that plays an important role in improving crop yield. Excessive P fertilizer application is widespread in agricultural production, which not only wastes phosphate resources but also causes P accumulation and groundwater pollution. Here, we hypothesized that the apparent P balance of a crop system could be used as an indicator for identifying the critical P input in order to obtain a high yield with high phosphorus use efficiency (PUE). A 12-year field experiment with P fertilization rates of 0, 45, 90, 135, 180, and 225 kg P2O5ha−1was conducted to determine the crop yield, PUE, and soil Olsen-P value response to P balance, and to optimize the P input. Annual yield stagnation occurred when the P fertilizer application exceeded a certain level, and high yield and PUE levels were achieved with annual P fertilizer application rates of 90–135 kg P2O5ha−1. A critical P balance range of 2.15–4.45 kg P ha−1was recommended to achieve optimum yield with minimal environmental risk. The critical P input range estimated from the P balance was 95.7–101 kg P2O5ha−1, which improved relative yield (>90%) and PUE (90.0–94.9%). In addition, the P input–output balance helps in assessing future changes in Olsen-P values, which increased by 4.07 mg kg−1of P for every 100 kg of P surplus. Overall, the P balance can be used as a critical indicator for P management in agriculture, providing a robust reference for limiting P excess and developing a more productive, efficient and environmentally friendly P fertilizer management strategy.

In this work, octahedral, cubic, particle-like, spherical and rod-shaped nano-CeO2supports were synthesized by hydrothermal method. CuO/CeO2catalysts were then prepared viaan ultrasonic-assisted impregnation method, employing these differently shaped CeO2supports. The resulting catalysts were tested for their performance in CO oxidation. The findings revealed that the CuO active sites significantly influenced the oxygen storage and release capacity of CeO2, thereby improving its catalytic activity for low-temperature CO oxidation. The key factors affecting the CO oxidation performance of CuO/CeO2catalysts with different CeO2morphologies were investigated through various characterizations. It was found that the specific surface area was not the primary factor in determining catalytic activity. Instead, the exposed crystal planes played a crucial role. By adjusting the crystal plane exposure of CeO2, the supported 1CuO/CeO2catalysts exhibited different crystal surface configurations. Notably, the 1CuO/CeO2-S catalyst, with exposed (100) and (110) crystal planes, and the 1CuO/CeO2-P catalyst, with exposed (111), (100), and (110) planes, exhibited higher surface defect concentrations. This increased defect concentration facilitated the formation of Cu+species, enhancing the redox properties and further improving the overall catalytic performance of CO oxidation.

Fresh-cut cantaloupe is very perishable due to the mechanical damage and susceptibility to microorganism infections, which limit their shelf life. Cantaloupe is a popular fruit with high moisture content and nutritional value. This study aimed to enhance fresh-cut cantaloupe quality and extend the shelf life by employing soy protein isolates (SPI) coating solutions containing calcium lactate (CaL) and λ-aminobutyric acid (GABA). Cold plasma (CP) was used to augment the antioxidant and antimicrobial activities of the coatings. The coatings were meticulously characterized, and their impact on fresh-cut cantaloupe was assessed through physicochemical and microbiological parameters. The incorporation of CaL and GABA and the CP treatment heightened the antioxidant activity of the SPI coating, resulting in a substantial increase in DPPH and ABTS free radical scavenging activities by 58% and 30%, respectively. Application of the composite coating included a noteworthy 24% reduction in water loss on fresh-cut cantaloupe, maintaining color stability and total soluble solids content. Moreover, the treatment of composite coating effectively controlled microbial growth, ensuring fresh-cut cantaloupe remained in an edible state at the conclusion of the storage period. The coating treatment has extended the shelf life of fresh-cut cantaloupe from 6 d to 10 d at 0 °C. In conclusion, the CP-treated bioactive coating containing CaL and GABA prolonged the shelf life, enhanced nutritional value, and preserved the microbial quality attributes of fresh-cut cantaloupe.

[Display omitted] In this work, the uniform Cu 2 O submicron-cubes were facilely synthesized by liquid phase reduction method. Then, the Cu 2 O submicron-cubes were further oxidized into Cu 2 O-CuO heterojunction with tunable Cu2+/Cu+ ratios and CuO submicron-cubes by controlling the calcination temperature. The phase transition period during calcination was real-time monitored by the in-situ XRD and in-situ DRIFTS. The obtained materials were investigated as the catalysts of CO oxidation. The results revealed that the Cu 2 O-CuO heterojunction catalysts performed much higher catalytic activities than the Cu 2 O and CuO counterparts. Because the synergistic effect of the heterojunction (Cu2+/Cu+) could increase the surface oxygen vacancy concentration. Furthermore, it was also found that only the Cu 2 O-CuO heterojunction structure with the appropriate Cu2+/Cu+ ratio behaved the optimum catalytic activity. The kinetic studies indicated that the apparent activation energy of CO oxidation was greatly affected by the Cu2+/Cu+ ratio. Therefore, these Cu 2 O-CuO submicron-cubes with heterostructure were considered as the promising CO oxidation catalysts. [ABSTRACT FROM AUTHOR]

[Display omitted] • Mesoporous nanosponge MFI supported Ni based catalysts for CO 2 methanation. • Mesoporous nanosponge MFI possessed both mesoporous and microporous channels. • The confinement effect of mesopore stabilized the metallic Ni active sites. • The penetrating effect of micropore made metallic Ni active sites more accessible. • La 2 O 3 modification enhanced the surface basicity and dispersion of metallic Ni. The mesoporous nanosponge MFI silicate zeolite was facilely fabricated by employing the long chain ammonium as the structure-directing agent. The zeolite with both mesoporous and microporous channels were selected as the support of Ni-La catalysts for methanation of CO 2. Various techniques were used to characterize the catalysts systematically. The effects of the La 2 O 3 promotor and pore morphology of the support on the catalytic performance were carefully investigated. Our study demonstrated that La promoter could be beneficial to the increase of the surface basicity and the enhancement of the metallic Ni dispersion. This would intensify the processes of the CO 2 chemisorption and H 2 dissociation in CO 2 methanation. Besides, we also found that the catalyst supported on mesoporous nanosponge MFI zeolite performed higher activity and better long-term stability than the reference catalysts supported on bulk MFI and MCM-48, suggesting that the synergistic effect between the mesoporous and microporous channels displayed unique advantages. Kinetic study revealed that both the nanosponge structure and La 2 O 3 promoter contributed to decreasing the reaction activation energy. Therefore, the present highly dispersed Ni-La catalyst over mesoporous nanosponge MFI zeolite promised a potential catalyst candidate for low-temperature CO 2 methanation reaction. [ABSTRACT FROM AUTHOR]

The Ni monometallic catalyst usually exhibits poor CO2methanation activity, although its low cost is beneficial for conducting large-scale application in industries. Herein, the transition metal (Mn, Fe, Co, and Cu)-doped Ni-based bimetallic catalysts loaded on mesoporous Ce0.8Zr0.2O2solid solution were prepared to address this challenge in CO2methanation. We found that the Co-doped catalysts exhibited much higher activity than the corresponding counterparts. Therefore, the relationship between the Co/Ni ratio and activity was further investigated to acquire the optimum ratio. The obtained catalysts were characterized by various measurements. The results demonstrated that doping the second transition metals could promote Ni dispersion and strengthen metal–support interaction. Resultantly, serious agglomeration of the metallic active sites was successfully inhibited. Besides, we also carried out the in situdiffuse reflectance infrared spectroscopy and online temperature-programmed surface reaction of CO2methanation to study the possible reaction intermediates and pathways over the Ni–Co bimetallic catalysts. A dynamic study was also conducted to further study the effect of the doped transition metals on the apparent activation energies. Besides, the present research also revealed that the Ni–Co synergistic effect significantly improved the low-temperature activity by regulating the reaction intermediates. As a result, the Ni–Co bimetallic catalysts supported by mesoporous Ce0.8Zr0.2O2solid solution were considered as a series of promising and efficient low-temperature CO2methanation catalysts.

Ovarian endometriosis is characterized by the growth of endometrial tissue within the ovary, causing infertility and chronic pain. However, its pathophysiology remains unclear. Utilizing high-precision single-cell RNA sequencing, we profile the normal, eutopic, and ectopic endometrium from 34 individuals across proliferative and secretory phases. We observe an increased proportion of ciliated cells in both eutopic and ectopic endometrium, characterized by a diminished expression of estrogen sulfotransferase, which likely confers apoptosis resistance. After translocating to ectopic lesions, endometrial epithelium upregulates nicotinamide N-methyltransferase expression that inhibits apoptosis by promoting deacetylation and subsequent nuclear exclusion of transcription factor forkhead box protein O1, thereby leading to the downregulation of the apoptotic gene BIM. Moreover, epithelial cells in ectopic lesions elevate HLA class II complex expression, which stimulates CD4+T cells and consequently contributes to chronic inflammation. Altogether, our study provides a comprehensive atlas of ovarian endometriosis and highlights potential therapeutic targets for modulating apoptosis and inflammation.

Surface-enhanced Raman scattering (SERS), owing to its high sensitivity and rapid response, has been widely used in various fields. However, it is still a challenge to prepare SERS substrates with high stability and reproducibility. Metal–organic frameworks (MOFs), with excellent enrichment capacity and stability, provide a new material for high-performance SERS substrates. In this paper, we prepare a MIL-101(Cr) film via a secondary growth method, and Ag+is reduced to Ag NPs by UV irradiation and attach to the film to synthesize the Ag@MIL-101(Cr) film SERS substrate. Then, we change the time of UV light illumination and the amount of silver nitrate in order to obtain the optimal substrate. The detection capability of this sample can be up to 10–11M for 4-ATP, and the relative standard deviation (RSD) is only about 5%, which demonstrates that the substrate has excellent SERS effect and reproducibility. Finally, the prepared substrate has been applied for the determination of nitrofurantoin, with its detection capability up to 10–7M. This work proposes a simple method to synthesize MOF-based film substrate with high SERS performance and uniformity and provides potential for the sensitive detection of chemical or antibiotic residue.

In recent years, the global greenhouse effect has been receiving more and more attention due to the increasing emission of greenhouse gases. CO2and CH4have been widely considered as the main greenhouse gases causing global warming and climate change. The CO2reforming of CH4(CRM) reaction can simultaneously convert both CO2and CH4into value-added synthesis gas (H2+ CO) and also alleviate the emission of these two greenhouse gases. Ni-Based catalysts have been widely investigated as the most promising candidates for CRM owing to their advanced activities and low price. However, the Ni-based catalysts usually suffer rapid deactivation due to the thermal sintering of metallic Ni active sites and surface carbon deposition during the CRM reaction at high temperatures (>640 °C). To address this challenge, researchers worldwide have devoted great efforts to developing highly efficient and stable Ni-based catalysts. However, it is extremely difficult to achieve this aim by using the traditional supported catalysts because of the weak metal–support interaction. Therefore, the concept of Ni-based confinement catalysts, such as core–shell catalysts, mesoporous catalysts, layered catalysts, and Ni-containing crystalline compound catalysts, have been proposed and developed to address the challenge of the thermal sintering of the metallic Ni active sites by the space and/or lattice confinement effects of these structures. As a result, the metallic Ni active site can be firmly stabilized and the surface carbon deposition can be effectively inhibited owing to the size effect of the metallic Ni active sites. This review mainly summarizes the state-of-the-art progress of the Ni-based confinement catalysts with advanced performances for CRM. Specifically, the Ni-based catalysts with different confinement types, including pore channel confinement, core–shell structure confinement, interlayer structure confinement, and crystalline lattice confinement, have been summarized. The significant impacts of the confinement effect on the stabilization of the Ni-based CRM catalysts are discussed in detail. The influences of the preparation methods on the catalytic performance of the Ni-based catalysts are also discussed and their development trends have been determined.

4′-O-methylpyridoxine (MPN) and its 5′-glucoside (MPNG) in Ginkgo bilobaseeds cause poisoning. Sample preparation for high-performance liquid chromatography was optimized to determine the amounts of MPN and MPNG at various extraction temperatures and pH levels. The effects of heating treatment on MPN and MPNG were investigated. MPNG was the main MPN analog in raw G. bilobaseeds under the optimal temperature (0 °C) and pH (2.5). Boiling decreased the contents of MPN (81.76%), MPNG (9.15%), and total MPN (TMPN, 30.14%). The contents of MPN and TMPN considerably decreased (80.41% and 20.11%, respectively), whereas that of MPNG increased (4.42%) after microwave treatment. Results demonstrate that boiling can reduce the toxicity of G. bilobaseeds for consumption.

Emerging evidence revealed that thyroglobulin (TG) contributes to the development of autoimmune disease, and the relationship between TG and autoimmune thyroid disease (AITD) is still controversial. The aim of this study was to quantify the association between rs2076740, rs853326, rs180223, and rs2069550TG polymorphisms and risk of AITD using a meta-analysis approach. We identified all studies that assessed the association between TG polymorphisms and AITD from PubMed, Embase, and Web of Science databases. A total of 3013 cases and 1812 controls from ten case–control studies were included. There was no significant associations found between rs2069550, rs180223, and rs853326polymorphisms and AITD risk. The association between the rs2076740polymorphism and AITD risk was significant in the codominant model (P= 0.005), suggesting the CC rs2076740genotype might be a protective factor for AITD. Sensitivity analysis by removing one or two study changed the results in dominant rs2076740and rs853326and rs2069550allele models (P= 0.016, 0.024, 0.027). Latitude and ethnicity significantly affected the association between rs2076740and rs2069550polymorphisms and AITD, indicating their protective effects in allele or dominant model (P= 0.012, 0.012, 0.012, 0.009, 0.009). The association between rs2076740, rs2069550, and rs853326polymorphisms and AITD risk is significantly affected by study characteristics.

A series of mesoporous nanocrystalline Ce–Zr solid solutions with different Ce/Zr ratios were successfully synthesized by the evaporation-induced self-assembly strategy, and were employed as catalytic supports of CuO-based catalysts for CO oxidation. These supports and catalysts were systematically characterized by X-ray powder diffraction (XRD), N2physisorption, transmission electron microscopy (TEM), energy-dispersed spectroscopy (EDS) mapping, X-ray photoelectron spectroscopy (XPS), H2temperature programmed reduction (H2-TPR), CO2temperature programmed desorption (CO2-TPD), etc.The catalytic performances toward CO oxidation had been carefully evaluated over these CuO-based catalysts. The effects of various influencing factors, such as the Ce/Zr ratio, mesostructure, redox properties of the support, CuO loading amount and calcination temperature, on the low-temperature catalytic activity had been carefully investigated. The results showed that the catalyst supported on the support with a Ce/Zr ratio of 80/20 exhibited the highest catalytic activity. It was also found that the Ce–Zr solid solution mesoporous catalysts exhibited much higher catalytic activity than the counterparts without evident mesostructure, demonstrating the advantages of the mesoporous catalysts by providing more accessible catalytically active sites. Besides, the mesoporous Ce–Zr solid solution-supported catalysts with excellent redox properties displayed much better catalytic performances than the commercial γ-Al2O3-supported catalyst. The kinetic study also indicated that the apparent activation energy of the CO oxidation process was greatly affected by the Ce/Zr ratio, mesostructure, and redox properties of the support. Overall, the present CuO-based catalysts with mesoporous nanocrystalline Ce–Zr solid solutions as supports were considered as a series of promising catalysts for CO oxidation.

The antivitamin B6, 4′-O-methylpyridoxine (MPN); its glucoside, 4′-O-methylpyridoxine-5′-glucoside (MPNG); and vitamin B6compounds, including pyridoxal (PL), pyridoxamine, pyridoxine, pyridoxal-5′-phosphate (PLP), and pyridoxamine-5′-phosphate, exist in Ginkgo bilobaseeds, which are widely used as food and medicine. This work aimed to determine the MPN analogues in G. bilobaseeds at different growth stages in terms of cultivars and ages of trees. The highest total MPN contents of 249.30, 295.62, and 267.85 μg/g were obtained in the mature stages of three selected G. bilobasamples. The total contents of vitamin B6compounds decreased significantly in the entire growth period of the three samples. Principal-component analysis revealed that MPN and MPNG were important contributors in the MPN-analogue metabolism of G. bilobaseeds. The influence of the cultivar on the content and composition of MPN analogues was greater than that of the age of the G. bilobatree.

This study aimed to provide a comprehensive overview of the pigment and non-pigment phenolic profile of polyphenol extracts of jujube peel and their bioactivities. Firstly, the pigment and non-pigment phenolic composition as well as antioxidant activities of free and bound polyphenol extracts in jujube peel were compared among twelve varieties systematically. Then the antioxidant and lipid-lowering activities of free and bound polyphenol extracts of ‘Junzao’ jujube peel were investigated representatively. Overall, 23 phenolic compounds were identified, in which flavonols were the main pigments and all varieties showed similar qualitative patterns but different quantitative characteristics. The antioxidant activities significantly correlated with the content of total phenolics and total flavonoids. Furtherly, both free and bound polyphenol extracts of ‘Junzao’ jujube peel exhibited DPPH, ABTS free radical scavenging capacity, and oxygen radical absorbance capacity in a dose-dependent manner. Besides, both of them improved the resistance of Caenorhabditis elegansunder H2O2oxidative stress and heat stress at 37 °C (20–100 μg/mL). What's more, compared to free polyphenol extract, bound polyphenol extract decreased the level of body lipid accumulation and triglyceride more effectively. These results suggest that jujube peel is an exploitable source of natural flavonoid pigments and phenolic ingredients with strong antioxidant and lipid-lowering properties.

Toluene is the most common volatile organic compound (VOC), and the MnO2-based catalyst is one of the excellent nonprecious metal catalysts for toluene oxidation. In this study, the effects of MnO2precursors and the support types on the oxidation performance of toluene were systematically explored. The results showed that the 15MnO2/MS-CeO2-N catalyst with Mn(NO3)2·4H2O as the precursor and the mesoporous CeO2nanosphere (MS-CeO2) as the support exhibited the most excellent performance. To reveal the reason behind this phenomenon, the calcination process of the catalyst precursor and the reaction process of toluene oxidation were investigated by in situDRIFTS. It was found that the MnO2precursor and the type of catalyst support could have a large effect on the reaction pathway and the produced intermediates. Therefore, the roles of the MnO2precursor and the type of support should be key considerations when developing the high-performance MnO2-based toluene oxidation catalyst.

Magnesium-based hydrogen storage powders were prepared by reactive milling under hydrogen atmosphere. The crystallitic carbon, prepared from anthracite coal by demineralization and carbonization, was used as milling aid and synergic hydrogen storage additive of magnesium. Dispersive powders of particle size about 20 to 60 nm and hydrogen capacity of 4.78 wt.% were prepared from magnesium with 40 wt.% of crystallitic carbon by 3 h of milling under 1 MPa of hydrogen atmosphere. The hydrogen stored in carbon increased with the addition of Al, Mo, Co and Fe. FT-IR showed that the carbon atoms at the edges of crystallitic carbon particles were hydrogenated into C-H during reactive milling with hydrogen. The initial dehydrogenation temperature of hydrogen-storage material 60Mg40C is 275.8 oC, and its dehydrogenation plateau pressure at 300 oC is 0.2 MPa and the length of the plateau is 5.0 wt.% of hydrogen capacity.

Magnesium alloys exhibit great application potential in industries such as automotive, electronics, aerospace and others. But poor wear resistance and corrosion resistance have restricted their actual uses. In this study, a CrN film had been prepared on magnesium alloy AZ91 by arc-glow plasma depositing. The composition and microstructure of the coating had been analyzed by X-ray diffraction (XRD) and glow discharge spectrum (GDS). The morphology of CrN film has been surveyed through scanning electronic microscopy (SEM) and atom force microscopy (AFM). The wear behavior was investigated through ball-on-disc test. The corrosion behavior in 5 wt% NaCl solution was also studied. The results indicate that the specific wear ratio decreases greatly and the corrosion potential also increases relatively comparing to AZ91 matrix.

A facile, rapid and efficient method for the synthesis of molecular tweezers containing chiral unsymmetrical urea unit in solvent-free conditions using microwave was reported.

With advantages of high specific strength, low elastic module, good damping property et al., the magnesium alloys exhibit great potential applications in aerospace. But poor wear behavior results in limited use of magnesium alloy to static components. In this study, a 2 μm thick coating with 12 sub-layers of CrN and TiN is deposited alternately on the surface of magnesium alloy AZ91 by a novel method of arc-glow plasma depositing to improve its wear resistance. The composition and microstructure of the coating layer are analyzed by means of SEM, XRD and GDS. The friction coefficient is measured by ball on disc rubbing test, and the wear rates are also calculated. The results indicate that the friction coefficient is increased, but the wear rate is dropped sharply as compared with bare metal. The surface hardness is about HK0.011400.

Arc-aided glow discharge plasma penetrating technique is a new surface coating method. With the help of vacuum arc discharge, a cold cathode arc source continually emits ion beams of coating elements with high currency density and high ionizing ratio. As the ion bombard working on, nitrogen is let in the chamber simultaneously. Then the surface of the parts formed ceramic coatings. Under lab condition, a commercial magnesium alloy Az91 had been coated with TiN film layer with the aim of improving the corrosion resistance. This paper mainly summarizes the testing and analyzing of the coating layer. The composition and microstructure of the coating layer had been analyzed by means of X-ray diffraction (XRD) and glow discharge spectrum (GDS), and the surface appearance had been surveyed by scanning electronic microscope (SEM). The adhesion strength between film and matrix had been evaluated by experiments of sticking-tearing. The results indicated that the coated layer on magnesium alloy were homogeneous, dense and robustly adherent.

In order to give a complex and accurate description about the sensitivity of efficient portfolios to changes in asset's expected returns, variances and covariances, the joint effect of estimation errors in means, variances and covariances on the efficient portfolio's weights is investigated in this paper. It is proved that the efficient portfolio's composition is a Lipschitz continuous, differentiable mapping of these parameters under suitable conditions. The change rate of the efficient portfolio's weights with respect to variations about risk-return estimations is derived by estimating the Lipschitz constant. Our general quantitative results show that the efficient portfolio's weights are normally not so sensitive to estimation errors about means and variances. Moreover, we point out those extreme cases which might cause stability problems and how to avoid them in practice. Preliminary numerical results are also provided as an illustration to our theoretical results.In order to give a complex and accurate description about the sensitivity of efficient portfolios to changes in asset's expected returns, variances and covariances, the joint effect of estimation errors in means, variances and covariances on the efficient portfolio's weights is investigated in this paper. It is proved that the efficient portfolio's composition is a Lipschitz continuous, differentiable mapping of these parameters under suitable conditions. The change rate of the efficient portfolio's weights with respect to variations about risk-return estimations is derived by estimating the Lipschitz constant. Our general quantitative results show that the efficient portfolio's weights are normally not so sensitive to estimation errors about means and variances. Moreover, we point out those extreme cases which might cause stability problems and how to avoid them in practice. Preliminary numerical results are also provided as an illustration to our theoretical results.