Designing an architecture with the ability to temporarily capture one kind of charge carrier has a critical role to play in enhancing the performance of photocatalytic reactions. Here, we report that ...SrTiO3 nanofibers that have been treated with a brief method of H2 calcination in an H2/N2 atmosphere (denoted as STO-NH) form oxygen vacancies (OVs) and achieve significant improvement in performance in photocatalytic H2 production without the presence of cocatalysts. These OVs can trap photogenerated electrons, which inhibits the recombination of electrons and holes in both the surface and the bulk, thus improving the photocatalytic decomposition of water. Moreover, the concentration of surface OVs in STO-NH presents volcanic characteristics: the increase with rise in hydrogenation temperature, with a consequent increase in catalytic activity, indicates well-controlled formation of OVs. The existence and concentration of the OVs in STO-NH photocatalysts are investigated qualitatively through electron paramagnetic resonance, high-resolution transmission electron microscope and photoluminescence emission spectra. A reasonable photocatalytic mechanism is proposed that we expect to be able to provide significant guidance for future study.
DZ125 directional solidified superalloys show excellent bearing temperature ability and creep resistance and have been widely used to manufacture the advanced aviation engine blades parts. However, ...the high temperatures and stresses for longtime service would cause a loss of mechanical properties and service life. In this paper, the damaged alloys were repaired using hot isostatic pressing combined with rejuvenation heat treatment technology, where the irregular γ′ phases in damaged alloys are recovered to be cubic particles like original state and the creep cavities and casting porosities also reduce obviously compared with those in damaged state. The restorable alloys exhibit apparently higher tensile properties and hardness than the alloys in damaged state, which is close or even more than those of original alloy, and their elongation and rupture life can satisfy criterion completely. This method can be easily extent to repair other damaged superalloys.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
Fermentation of fruits offers a diverse range of flavors, smells, and colors. Colored fruits are rich in naturally occurring pigments, such as betacyanin. Hence, they are considered to possess ...powerful antioxidant activities. However, in wine production, such pigments often diversify the flavor and color of the wine. The objective of this study was to compare the quality of two types of wines: a single‐fruit (pitaya) wine and a mixed‐fruit wine that contains watermelon (Citrullus lanatus), mint (Mintha spicata), and pitaya (Hylocereus costaricensis). In this study, fresh pitaya, watermelon, and mint leaves were fermented using Saccharomyces cerevisiae. Juice extracts underwent fermentation at room temperature for 7 days under dark conditions. Physicochemical changes, such as pH, sugar content, specific gravity, and alcohol content, were observed daily. The antioxidant activities were measured by the 2,2‐diphenyl‐1‐picrylhydrazyl (DPPH) assay, the ferric reducing antioxidant power (FRAP) assay, and total phenolic contents (TPCs). After 14 days of fermentation, the alcohol contents of mixed and pitaya wine were 11.22% (v/v) and 11.25%, respectively. The total sugar content of the mixed wine was 8.0 °Brix, while that of pitaya wine was 7.0 °Brix. Moreover, pitaya wine exhibited a higher TPC (22.7 mg GAE/100 g D.W.), and better FRAP (3578 μmole/L) and DPPH scavenging ability (80.2%) compared to the mixed wine with a TPC of 21.4 mg GAE/100 g D.W., FRAP of 2528 μmole/L, and DPPH of 75.6%., while the addition of watermelon and mint did not change the alcohol percentage contents of wine.
This is the first paper to demonstrate the anti‐oxidative ability and sensory evaluation in different types of pitaya wines.
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FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
Given increasing energy demands and environmental pollution, it is highly desirable to design new hydrogen evolution reaction (HER) catalysts. In this study, we have performed high throughput ...screening of transition-metal borides (M
2
B) and Janus counterparts for appealing catalysts. The simulations showcase that the Pd
2
B, PdPtB, PdIrB and PdAuB possess favorable HER performance with the different chemical nature and unique asymmetry structure. To our surprise, PdIrB monolayer has an ultralow hydrogen adsorption free energy (Δ
G
H
) ranging from 6 to 92 meV for HER reaction, which is even comparable to that of Pt. Our current results may pave the way to design high-performance and easy-accessible HER catalysts.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
The practical energy density of lithium–sulfur batteries (LSBs) is seriously limited by the high electrolyte-to-sulfur ratios (E/S). The E/S can be reduced by employing hosts with easy-to-infiltrate ...structure that ensures the uniform distribution of a lean electrolyte and high catalytic activity that can suppress "shuttle effect" via accelerating the slow conversion of soluble polysulfides to insoluble sulfides. Among the easy-to-infiltrate structures, the three-dimensional-ordered macroporous (3DOM) structure is easier to scale preparation and more suitable for the existing industrial processes. However, it is difficult to obtain the 3DOM with (1) high penetrability due to the high viscosity of frequently-used organic polymer precursors and (2) high catalytic activity due to the low confinement effect, meaning that uniformly dispersed small-sized catalytic materials are difficult to load on 3DOM. Herein, using carbon dots (CDs) with both organic and inorganic properties as a precursor and aggregation limiting agent, a 3DOM host with high penetrability and homodispersed Ni particles of small sizes (Ni-CDs-3DOM) was synthesized. In this host: (1) CDs precursor with suitable viscosity can improve the penetrability. (2) CDs can effectively inhibit the agglomeration of Ni particles. (3) Uniformly dispersed small-size Ni particles offer high-efficiency catalytic activity toward sulfur reactions. Consequently, the Ni-CDs-3DOM/sulfur cathode exhibits high sulfur utilization and stable cycling performance even under high sulfur loading (5.5 mg·cm
−2
) and low E/S (6.5 μl·mg
−1
). This work indicates the usefulness of CDs in constructing hosts for LSBs with high energy density.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
Herein, ultralong and efficient phosphorescence has been achieved from silica confined carbon nanodots (CNDs) in acqueous solution, and the lifetime and phosphorescence quantum yield of the CNDs are ...1.86 s and 11.6 %, both of which are the best values ever reported for water-soluble phosphorescent nanoparticles. In terms of the efficient phosphorescence, in vivo/vitro afterglow imaging has also been demonstrated, which addresses demonstration of CNDs in afterglow bioimaging.
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•Water-soluble phosphorescent CNDs with world-record lifetime and quantum yield of 1.86 s and 11.6% have been achieved.•The silica layer increases the stability of the triplet excitons in CNDs.•In vivo/vitro afterglow imaging has been demonstrated with our proposed CNDs.
Water-soluble phosphorescent nanoparticles are highly desirable for biomedical applications. However, the phosphorescence of nanoparticles is usually quenched in aqueous solutions due to the nonradiative deactivation of triplet excitons by the oxygen in water, thus it is a huge challenge to realize water-soluble phosphorescent nanoparticles. Herein, ultralong and efficient phosphorescence has been achieved from water-soluble carbon nanodots (CNDs) by confine CNDs in a nanospace. Silica capsulation layer is used to ensure the solublity of the CNDs, isolate the CNDs from the surrounding oxygen in the aqueous solution. Furthermore, the motion and vibration of covalent bonds in the CNDs are limited. In this way, the nonradiative deactivation rates of triplet excitons has been decreased, and efficient phosphorescence is achieved from water-soluble CNDs. The lifetime and phosphorescence quantum yield of the CNDs are 1.86 s and 11.6 %, both of which are the best values ever reported for water-soluble phosphorescent nanoparticles. In terms of the efficient phosphorescence of the CNDs in aqueous solution, in vivo/vitro afterglow imaging is also been demonstrated.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Lemon (Citrus limon) flavedo, an outer green layer of lemon peel, is used in the bakery for its good smell and attractive color. However, most of the research has been focused lemon peel ...bioactivities. Currently, there are no data exist on flavedo individual bioactive compounds. Therefore, we compared three extraction processes (ultrasound-assisted extraction (UAE; 20 min), high-pressure processing (HPP; 400 MPa/10 min), and enzymatic hydrolysis (EH)) on two dried samples (oven-dried (OD); essential oil residues (EOR)) to understand the effect of flavedo extracts on the inhibition of carbohydrate hydrolyzing enzymes and their bioactive compounds. EH-treated samples exhibited higher carbohydrate hydrolyzing enzymes inhibition compared to UAE and HPP-treated samples (α-amylase inhibition of 25.83–93.77% for UAE and EH-treated OD samples, respectively). The phenolics in OD-EH was higher than EOR samples (3688 mg GAE/100 g and 2306 mg GAE/100 g) and SOD-like activity (3505 U/g and 2815 U/g). Moreover, sinapic acid (47.33% and 59.59%) and esculetin (16.85% and 18.31%) were the major compounds of the total phenolics in OD and EOR samples that may regulate obesity and blood sugar, respectively. Therefore, lemon flavedo might be considered as a potential source in the development of functional foods.
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•EH-samples exhibited a high carbohydrate hydrolyzing enzymes inhibition.•UAE-samples showed less phenolics than HPP and EH-samples.•HPP treated samples reported high DPPH and FRAP activity.•Esculetin and sinapic acid were the major bioactive compounds in lemon flavedo.•Lemon flavedo treated with EH recommended using in anti-diabetic food applications.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
In this study, the exercise prescription intervention rehabilitation suggestions for fatty liver patients were summarized as follows: first, basic exercises (brisk walking and jogging.), sports ...(swimming, badminton, and cycling), traditional Chinese medicine exercises (Taichi boxing and eight-section brocade), the aim of which is to improve overall physical strength and endurance of the body; second, exercise intensity, duration, and frequency; third, exercise precautions; and fourth, exercise prescription selection and suggestion.
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FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK, VSZLJ
Evaluation on sustainability of coastline utilization was one of the hot topics in marine environmental science. Based on high-resolution remote sensing images, coastlines can be divided into natural ...coastlines and artificial coastlines. Natural coastlines are mainly converted to harbor coastline and mariculture coastline. In this study, a new comprehensive model was proposed to assess the sustainability on utilization of coastline and applied to a typical case of Beibu Gulf, China. Comprehensive economic output efficiency (EOE) of artificial coastlines was obtained by integrating the contribution weight and applying linear combination model. In addition, the P–S-R framework integrated with fuzzy mathematics model and linear combination method was constructed to evaluate the disturbance intensity of human activities on the natural coastlines (DI) by taking petrochemical plants, ports, sewage outlets and aquaculture intensity as pressure indicators, seawater quality status near the coastline as state indicators, and whether the coastline was within nature reserve boundaries as the response indicator. Rely on the EOE and DI, the cities involved in the evaluation were finally categorized into four groups: group 1 with high economic output efficiency and low ecological impacts, group 2 with high economic output efficiency and high ecological impacts, group 3 with low economic output efficiency and low ecological impacts, group 4 with low economic output efficiency and high ecological impacts. The results showed that: (1) natural coastlines retention ratios were 52.45%, 57.97% and 76.15% in Guangdong, Guangxi and Hainan Province respectively. In addition, 8.66%, 10.47% and 5.17% of the coastlines with high disturbance from human activities in Guangdong, Guangxi and Hainan Province respectively were identified; (2) only 4 of 29 cities were categorized into the group with high economic output and low ecological impacts, indicating that most of the coastal cities in Beibu Gulf of China was at a relatively low level of sustainability. The proposed indices system and the integrated analysis framework were proved to be feasible for evaluating sustainable utilization of coastlines, which can be applied to other case studies. The results of evaluation provided valuable information for decision-makers to optimize coastal land use policy targeting at the balance of development and conservation.
•Spatial pattern of natural coastline was obtained based on high-resolution RS data.•A new model was proposed for evaluating sustainable utilization of coastline.•A P–S-R indices system was constructed for ecological impact assessment.•A model for characterizing comprehensive economic output efficiency was proposed.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
With the advantages of metal conductivity, large specific surface area, and rich surface functional groups, two-dimensional (2D) MXenes have shown great potential in the field of gas sensing. ...However, gas sensors fabricated with pristine MXenes generally suffer from several problems such as low sensitivity, poor selectivity, significant base-resistance drift, and poor environment stability. Therefore, many efforts have been devoted to overcoming these problems. In this review, we review the progress on MXene-based gas sensors and summarize several efficient strategies (including structural design, surface modification, inorganic Schottky junction/heterojunction sensitization, polymer addition, and metal-ion intercalation) to promote the gas-sensing performance. In addition, the major challenges and future development directions of MXene-based gas sensors are also outlined in the present review.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
