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The synergistic effect of Au NPs and Nd doping could improve the light utilization, promote the separation of photogenerated carriers and inhibit the recombination of photogenerated carriers, thus greatly improving the PEC performance of BFO.

Although Fe-based catalysts have made significant progress in Fischer–Tropsch synthesis, the effect of residual sodium on the structural properties and catalytic performance of Fe-based catalysts has been controversial. Herein, we report the positive role of residual sodium in the structural properties and performance of FeAlNa catalysts for olefins synthesis from syngas. Meanwhile, the as-prepared catalysts were characterized by the multiple characterization technique to reveal the positive role of residual sodium on the structural properties. The characterization results revealed that the residual sodium improved the reduction behavior of Fe species and adsorption ability of CO, and inhibited the secondary hydrogenation due to its weak adsorption ability of H2. Moreover, the residual sodium inhibited the interaction between Fe and Al. Importantly, a high olefins/paraffins ratio of 6.19 and low CH4 selectivity of 12.8% were achieved on the residual sodium modified FeAlNa catalyst. An in-depth understanding of the structural properties and catalytic performance of residual sodium on FeAl-based catalysts can provide a theoretical basis for the development of novel efficient catalysts and large-scale applications for olefins synthesis from syngas.

To identify the associations of clinical and magnetic resonance (MR) features with overall survival (OS) in patients with unresectable hepatocellular carcinoma (HCC) achieving complete response (CR) after conventional transcatheter arterial chemoembolization (TACE) and to further develop an individual nomograph to estimate the survival probability.A total of 112 patients with unresectable HCC treated with TACE as first-line treatment were retrospectively evaluated. Potential risk factors associated with OS were identified by univariate and multivariate Cox analyses. The survival model was developed by multivariate Cox proportional hazard model. The area under the receiver operating characteristic curve was calculated to assess the performance of each marker and of the whole model. Discrimination was performed using Kaplan-Meier curves, and the survival curves were compared by the log-rank test. A nomogram derived from the survival model was established.Multivariate Cox analyses indicated that nonsmooth tumor margin, peritumoral enhancement, fat sparing in solid mass, and Barcelona clinic liver cancer (BCLC) stage were independent risk indicators associated with OS. The survival model showed acceptable diagnostic power, with an area under the curve (AUC) of 0.687. Kaplan-Meier curves demonstrated that the model discriminated well, as the high-risk and low-risk groups had median survival times of 21.6 months and 34.8 months, respectively (log-rank test, P = 0.01).Nonsmooth tumor margin, peritumoral enhancement, fat sparing in solid mass, and BCLC stage were potential biomarkers to evaluate the survival with favorable performance and discriminate HCC patients with CR under conventional TACE treatment.

This paper focuses on the current urgent demand for the accurate measurement of forest inventory variables in the fields of forestry carbon sink measurement, ecosystem research, and forest resource conservation, and proposes the use of images to construct a three-dimensional measurement model of forest inventory variables, which is a new method to realize the automatic extraction of forest inventory variables. This method obtains sample site information by using high-definition images taken in the forest by a smartphone, which significantly improves the field operation efficiency and simple operation, and effectively alleviates the problems of long field operation times, complicated operations, and expensive equipment used by current methods for obtaining forest inventory variables. We propose to optimize the Eps parameters of the DBSCAN algorithm based on the MVO algorithm for point cloud clustering to obtain single wood point clouds, which improves the accuracy of the model and can effectively solve the problem of large interference from human factors. The scale coefficients of the image and the actual model are obtained by the actual measurement of tree height and diameter at breast height to complete the construction of the three-dimensional measurement model of the stand and are then combined with the AdQSM algorithm to realize the automatic extraction of forest inventory variables, which provides a new interdisciplinary method for the comprehensive extraction of forest inventory variables. The accuracy of the model measured in the experimental sample site of Fraxinus mandshurica Rupr was as follows: the absolute error of tree height measurement ranged from 0.05 to 0.37 m, the highest relative error of measurement was 2.03%, and the average relative error was 1.53%; for the absolute error of diameter at breast height, measurement ranged from 0.007 to 0.057 m, the highest relative error of measurement was 7.358%, and the average relative error was 3.616%. The method proposed in this study can be directly applied to the process of acquiring and visualizing the variables of forest inventory in the field of ecological research, which has good flexibility and can meet individual research needs.

Emerging hydrogen energy storage technologies present a potential opportunity to increase the flexibility and resiliency of the integrated power and transportation system with ultra-high penetration of renewable energy. This paper studies a conceptual integrated energy-mobility system (IEMS) based on renewable-to-hydrogen stations (RHSs) and tank truck fleets. In an RHS, the renewables power the grid while also charge a hydrogen energy storage unit that can perform power-to-hydrogen (P2H) and hydrogen-to-power (H2P) operations. Besides, using tank truck fleets, the RHS will distribute its surplus hydrogen products to local consumers, e.g., refueling stations serving hydrogen fuel cell vehicles. The operation framework of the IEMS is analyzed, and some preprocessing technologies are developed to reduce modeling complexity, then, a joint optimal scheduling model, involving renewable generation contract, P2H, and H2P of the station, hydrogen product demands of the local consumers, vehicle routing problem of the truck fleets, is established. Afterward, the formulated problem is solved by a heuristic method based on the Exhaustive Search and Genetic Algorithm. Numerical results verify the effectiveness of the joint optimal scheduling model and illustrate that the IEMS has the potentials to promote hydrogen-integrated transportation and power systems.

Cordyceps acid is an active component of Cordyceps cicadae and has a variety of medicinal uses, including anti-tumor effects, the prevention of cerebral hemorrhaging and myocardial infarction, and the inhibition of a wide range of bacteria. The objectives of this study were to identify C. cicadae fungi and optimize the culture conditions to obtain a high yield of cordycepic acid. First, a wild C. cicadae was identified by morphological observation and rDNA sequence analysis. Secondly, the optimal fermentation conditions were determined using a single-factor method, a Plackett–Burman design, and a Box–Behnken response surface. Finally, using the yield of fruit bodies and the content of cordyceps acid as indices, combined with a single-factor experiment and a response surface design, the best combination of conditions for cultivation was determined. The results showed that the best combination was as follows: sucrose 2%, tryptone 2%, KH(2)PO(4) 0.4%, MgSO(4)·7H(2)O 0.4%, an initial pH of the fermentation liquid of 7.0, 5% inoculum, fermentation for 4.5 d, a ratio of medium to liquid of 1:1.7, illumination intensity 150 Lux, illumination time 15 h per day, and 70% humidity. The content of cordycepic acid in the fruiting bodies developed in cultivation was 2.07-fold higher than that in the wild C. cicadae. This study provides a theoretical basis for the large-scale cultivation of C. cicadae with a high concentration of cordycepic acid. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1007/s42770-022-00687-4.

Efforts have been made to find a better therapeutic approach with fewer side effects in treating chronic obstructive pulmonary disease (COPD). This study investigated the effect of Buyuan decoction (BYD) on autophagy in COPD rats. An experimental model with Sprague-Dawley rats was established by lipopolysaccharide (LPS) injection and cigarette smoke exposure. Rats were randomly allocated into blank control (normal control), experimental model, low-dose BYD (8.0 g/kg/day), medium-dose BYD (16.0 g/kg/day), high-dose BYD (32.0 g/kg/day) and 3-MA (methyladenine) groups (6 rats/group). Cell and tissue morphology were observed using hematoxylin and eosin staining. Autophagic vesicles were examined with a transmission electron microscope. Protein expression of LC3-II/I, BNIP- 1, ATG7, p62, PI3K and p-PI3K in lung tissue was detected by Western blotting. Compared with the experimental model group, the inflammatory infiltrate in lung tissue was reduced, the nuclei of the pulmonary epithelial cells were restored to normal, and the expression of LC3, BNIP1, ATG7 and p-PI3K was significantly downregulated, while p62 expression was significantly upregulated after treatment with the BYD. The effect was most significant in the low-dose BYD group (P

As the country hosting the most significant number of refugees in Europe, Germany’s Merkel government’s refugee policy has been repeatedly adjusted and plagued by inconsistencies and management failures. What factors have influenced the formation of the Merkel government’s refugee policy and its two shifts? The traditional rational decision-making model does not effectively explain government decisions’ motivation in complex challenges. This article develops a framework for analyzing “bounded rational decision-making”. It identifies the three factors that influenced the Merkel government’s refugee policy: (a) strict border controls, (b) welcome culture, and (c) welcome culture under restrained policies. It explains the process and logic of their development. Based on the theory of “bounded rational decision making”, the article examines the “key events and problem identification”, “goal selection”, “national interests”, and “political psychology”. We found that in the early stages of the refugee crisis, (a) public opinions and pressure, (b) the pursuit of a positive national image, and (c) a shift in the leader’s psychology led Merkel to shift away from a pragmatic and rational course. These factors led to the first shift in German refugee policy from “hesitation” to a “welcoming culture”. At the end of 2015, however, the shortcomings of the irrational policy were quickly revealed, and the frequency of refugee-related social problems reversed German public opinion, forcing Merkel’s government to seek a balance between humanitarianism and national interests. As a result, refugee policy was adjusted for the second time, returning to a strict refugee examination system. The development of the Merkel government’s refugee policy exposed the shortcomings of the traditional crisis decision-making model. Moreover, it provided a new perspective for rethinking the governance of the refugee crisis.

This study was conducted in a fluidized-bed incineration plant, evaluating the formation, emission and flux of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) from industrial-organic-solid-waste (IW) incineration. The results revealed that both the total (or I-TEQ) concentrations of toxic and 136 total PCDD/Fs in flue gas (FG), fly ash (FA) and bottom ash (BA)were ramped up to a higher level than those during municipal-solid-waste (MSW) incineration. A possible explanation was the chlorine (Cl) content of IW. However, the emitted PCDD/Fs in FG (FA/BA) still fulfilled the criteria. Subsequently, similar distribution patterns of PCDD/F isomers were observed in subsystems, indicating a unified formation-pathway. De novo synthesis was detected as the dominant formation-pathway of PCDD/Fs, while high-temperature and precursor syntheses were excluded. DD/DF chlorination formed PCDD/Fs to some extent. Furthermore, the mass flow chart indicated that PCDD/Fs output in primary FG was significantly strengthened (>1000 times) by de novo synthesis, from 1.25 μg I-TEQ/h to 1.67 mg I-TEQ/h. With effective cleaning by APCS, 99.6% of PCDD/Fs in FG were purified. PCDD/Fs in the gas phase were finally emitted at a discharge rate of 7.25 μg I-TEQ/h. However, accumulated FA took most PCDD/Fs into the environment (>99%), reaching 3.56 mg I-TEQ/h.

Photochromic wood was fabricated by coating microencapsulated photochromic material (MP)/polydimethylsiloxane composites onto wood using a simple drop-coating method. Urea-melamine–formaldehyde resin was used to microencapsulate the photochromic material (PM) via in situ polymerization. The concentration of the MP affected the photochromic property of the wood surface. The total color change (ΔE*) reached 82.2 when the concentration of the composite coating is 8%. Adhesion tests confirmed that the composite coating adhered firmly to the wood. This method is potentially useful for the production of functional wooden products, such as anti-counterfeiting materials and aesthetic wood.

In this work, considering the current status of conservative and complicated traditional thrombosis treatment methods, a kind of flexible intelligent probe (FIP) with a top-driven sensing strategy is proposed to realize the expected function of thrombosis accurate localization in a liquid flow environment. After throughput fabrication, we find that the FIP has excellent electrical conductivity and mechanical properties. Notable, our FIP with the principle of piezo-resistive sensing has a quasi-linear sensitivity (approx. 0.325 L per minute) to flow sensing in the low flow velocity range (0–1 L per minute). Via the well-designed magnetically driven method, our FIP has a maximum deflection output force of 443.264 mN, a maximum deflection angle of 43°, and a maximum axial force of 54.176 mN. We demonstrate that the FIP is capable of completing the specified command actions relatively accurately and has a good response to real-time sensing feedback performance, which has broad application prospects in thrombus localization detection.

To improve the dry friction behavior of traditional hard coatings, MoS2/PTFE lubricating coatings were prepared on the PVD TiN-coated cemented carbide using spray method. The influences of MoS2/PTFE lubricating coatings on the primary characteristics of TiN coatings were investigated. Reciprocating sliding tests were carried out with the TiN–MoS2/PTFE coated specimen (T-M-P) under dry sliding conditions, and the tribological behaviors were compared to those of the TiN-coated one (T-N). The test results indicated that the adhesion force of coatings with substrate for T-M-P specimen increased, the surface micro-hardness, roughness and friction coefficient significantly decreased. Meanwhile, the surface adhesions and abrasion grooves of T-M-P specimen were reduced, and the main wear forms of T-M-P were abrasion wear and coating delamination. The MoS2/PTFE lubricating coatings can be considered effective to improve the friction properties of traditional hard coatings.

The continued development of digital technology and its overuse in teaching and learning in the post-epidemic era have brought about digital health risks, which are associated with academic burnout among college students. This study focused on the relationship between classroom digital teaching and students’ academic burnout and designed the Classroom Burnout Inventory (CBI) and the Classroom Burnout Causes Inventory (CBCI) to conduct a cross-sectional survey of 206 Chinese university students. Correlations and regression analyses were conducted between key factors and burnout values through a path model of “Digital teaching-Teaching & learning process-Causes subjects-Burnout”. The results of the study show that an inappropriate and excessive use of unintegrated digital teaching and learning technologies in the classroom was positively correlated with academic burnout among college students. Burnout levels and the three manifestations were not correlated with students’ gender, grade, and major. In terms of causes, the academic burnout of college students was more correlated with their own personal reasons than with external factors such as teachers, universities, and environments. Integrating digital technology platforms, enhancing teacher leadership in the digital classroom, and strengthening peer support and students’ psychological resilience are all meaningful explorations of academic burnout prevention strategies.

Irrigation alleviates drought in croplands and maintains or increases crop yields. The accurate monitoring of irrigated areas is important to regional water resource management, food security, climate change, drought monitoring, and emergency disaster relief. Based on field experiments that demonstrate the feasibility of irrigated area mapping using land-surface temperature, we propose a method to map spring irrigation areas using historical meteorological data, main crop phenological characteristics, irrigation regimes, and MODIS land-surface temperature (LST) products. The distribution of irrigation intensity, spring irrigated areas (SIA, considering the irrigation intensity), and total area of spring irrigation (STIA, regardless of irrigation intensity) were monitored by the proposed method for the Donglei Irrigated District (Phase II) in northwestern China from 2011 to 2018. The spring irrigation of the study area was divided into three periods (16 January–23 February, 24 February–24 March, and 25 March–31 May). Then, the temperature threshold of the irrigated area in each period was determined by the diurnal temperature range (DTR) of the rain-fed plots and precipitation data; for the three periods, this was 12 °C, 15 °C, and 11 °C, respectively. The results showed that most of the croplands in the study area were irrigated once or twice. The SIA in most years varied between 55,900 and 73,100 ha, but in 2016, the irrigation area reached 100,200 ha. The STIA accounted for 60–70% of the irrigated area except 2016. The average accuracy of SIA monitoring was satisfactory and above 94% for years when sufficient and reliable data was available.

The river border positioning is an important part of river surveys, which is crucial for water conservation project development, water resource use, water disasters, river regime monitoring, and many other applications related to water resources. Currently, satellite images or field measurements are used to extract river channels. However, satellite images are insufficiently precise, and field measurement requires significant manpower and cost. In this paper, a new method for river channel extraction is proposed, which is based on the combination of Jenks natural breaks classification method and digital elevation model (DEM), and then the river channel range is complemented by using the water range monitored by GF-1(Gaofen-1 satellite) in flood season. The overall precision is greater than 85%, and the Kappa values achieve moderate stability (0.41–0.60). Using this method, the extraction of river range is practicable and achievable, and the higher the DEM resolution, the better the extraction result.

In order to improve the tribological behavior of Si3N4/TiC ceramics, DLC coating was fabricated on the ceramic surface through magnetron sputtering technology. The surface and cross-section micrographs, the adhesion between coating and substrate, the surface roughness and microhardness of the DLC-coated ceramics were investigated. Reciprocating friction tests sliding against cemented carbide ball were conducted under dry sliding conditions. The test results indicated that the DLC coating possessed superior tribological performance, which was conductive to decreasing the friction coefficient and enhancing the wear resistance of ceramics. The primary mechanisms responsible for performance improvement of the DLC-coated ceramics were attributed to the combined effects of low shear stress, excellent adhesion with substrate, high microhardness and good surface roughness. It was believed that the DLC coating was efficient in improving the load-carrying capacity and expanding the application area of ceramic materials.

To enhance the tribological performance of Si3N4/TiC ceramics, MoS2/PTFE composite coatings were deposited on the ceramic substrate through spraying method. The micrographs and basic properties of the MoS2/PTFE coated samples were investigated. Dry sliding friction experiments against WC/Co ball were performed with the coated ceramics and traditional ones. These results showed that the composite coatings could significantly reduce the friction coefficient of ceramics, and protect the substrate from adhesion wear. The primary tribological mechanisms of the coated ceramics were abrasive wear, coating spalling and delamination, and the tribological property was transited from slight wear to serious wear with the increase of load because of the lower surface hardness and shear strength. The possible mechanisms for the effects of MoS2/PTFE composite coatings on the friction performance of ceramics were discussed.

Summary A semi-convertible hydrogel with reversible photoresponsive supramolecular lubricating ability is demonstrated by integrating a responsive supramolecular system of α-cyclodextrins/polyethylene glycol (α-CD/PEG) and competitive guest 1-[p-(phenylazo)benzyl]pyridinium bromide (AzoPB) within a poly(vinyl alcohol) (PVA) and polyacrylamide (PAAm) framework. The competitive host-guest interaction between α-CD/PEG supramolecular network and AzoPB after UV and visible-light irradiation enables the appearance and disappearance of the sol-state layer on the hydrogel surface while the PVA and PAAm consistently keeps the framework. This semi-convertible process realizes the reversible photoresponsive lubricating ability and variable toughness. We envision that this finding will offer a possible way for fabricating novel smart devices far beyond lubrication, leading to an emerging branch of interdisciplinary materials science that integrates supramolecular chemistry, hydrogel, and surface science.

Antibiotic resistance is increasing to dangerous levels across the globe. A growing list of bacterial infections that lead to blood poisoning or foodborne diseases are becoming challenging to treat due to the loss of antibiotic efficacy. Studies on the antibacterial performance of Ag nanoparticles and other transitional metal oxides have gained increasing attention as an alternative therapeutic strategy. In this study, NiCo2O4 and Ag/NiCo2O4 composites with different contents of Ag were synthesized through a simple co-precipitation method. The composites were assessed via transmission electron microscopy (TEM), X-ray diffraction (XRD), and scanning electron microscopy (SEM). The results demonstrated that the morphology of NiCo2O4 was unaffected by the addition of Ag. The NiCo2O4 and Ag/NiCo2O4 composites with different contents of Ag showed a suitable size of approximately 10 nm. The NiCo2O4 and Ag/NiCo2O4 composites displayed potent activity against a range of disease-causing bacteria. The Ag/NiCo2O4 composites with low Ag content displayed weak antibacterial activity.

Eight groups of cellulose amorphous region models in which the mass fraction of water was separately 0%, 1%, 2%, 3%, 4%, 5%, 6%, and 7% were established using a molecular dynamics software material studio. The PCFF force field was selected to simulate the molecular dynamics of the model under the constant-pressure and constant-temperature (NPT) ensemble. The simulated temperature was set to 433.15 K. The experiment showed that the hydrogen bonds between cellulose chains affected the structure of cellulose, which led to the change of the end-to-end distance of the cellulose chain and the overall size of a cell. The diffusion degree of water molecules was closely related to the number of hydrogen bonds between cellulose and water. In the process of heat treatment of bamboo, the present simulation results suggest that the structure of bamboo may be damaged when the mass fraction of water vapor reaches or exceeds 7%.

Aqueous ZIBs are one of the most promising next-generation rechargeable batteries because of the high capacity, high hydrogen evolution overpotential, and chemically stable reversible plating/stripping of the zinc electrode in the mild aqueous electrolyte. However, there are limited cathode materials that can store Zn2+ reversibly with superior cycling and rate capability. Herein, hierarchically porous nanorods composed of twinborn α-(Mn2O3-MnO2) heterostructures are proposed as a robust cathode for Zn storage. Thanks to the hierarchically porous nanorod morphology and the abundant interface of the heterostructures involving a built-in electric field, the as-obtained twinborn α-(Mn2O3-MnO2) electrode delivers a high capacity of 170 mA h g-1 for 2000 cycles at 500 mA g-1 and shows an excellent rate capability of up to 1.5 A g-1 with a capacity of 124 mA h g-1. The inspiring results achieved exhibit the enormous potential of the high-performance heterostructure cathode for fast and stable ZIBs.

Studies on solar steam evaporation for potential application in desalination have attracted much attention due to its unique advantages of low energy consumption environmental friendliness, etc. However, water molecule transportation in the capillaries of solar steam evaporators to develop a high-efficiency solar evaporation system is critical but often ignored. This work reports high-yield and low-cost natural corn stalks as solar steam generators with ultra-fast water transportation in capillaries, multi-layer self-cleaning of sea salt, large seawater storage capacity, long-term anti-corrosion properties against seawater, low thermal conductivity, and excellent evaporation properties. This solar steam evaporator with the conventional photothermal coating by multi-walled carbon nanotubes and titanium dioxide (Mcnt-TiO2) exhibits an outstanding evaporation rate of 2.48 kg m−2 h−1 and evaporation efficiency of 68.2% under solar light. These advantages are significantly attributed to the natural structural features of the stem marrow of corn stalks including scattered vascular bundles with super-hydrophilic properties achieving high-speed water moisture transportation, porous basic tissues with layer by layer bio-filtration, porous cavities realizing multi-stage filtration, transportation and storage of seawater, and low moisture enthalpy and heat loss. Meanwhile, an efficient and low-cost solar desalination device via bundling pluralities of corn stalks is developed to collect freshwater, and the average daily freshwater amount per unit area (4.3–5.8 kg m−2 on sunny days and 3.0–3.9 kg m−2 on cloudy days) can meet the daily water needs of more than twenty adults. These findings not only provide the possibility of discovering corn stalks as low-cost, scalable, highly efficient evaporation-based heat transfer devices for future efficient desalination, but also present an innovative inspiration for reducing the greenhouse effect brought by corn stalk burning, which promotes the efficient use of bio-mass straws.