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[Introduction] The heater’s terminal temperature difference is one of the main reasons that affect the heat economy of the unit. It has great significance to accurately and quantitatively calculate the effect of heater’s terminal temperature difference on heat economy. [Method] A 660 MW unit was taken as the research object, the equivalent heat drop method was used to calculate the effect of the heater’s terminal temperature difference on the heat rate under the four operating conditions of THA, 80% THA, 60% THA and 40% THA. The influence of the terminal temperature difference of the same stage heater on the heat rate under different working conditions and its changing law were analyzed. [Result] The results showed that the terminal temperature difference of the last stage high pressure heater and No.2 low pressure heater have a greater influence on the heat rate under various operating conditions. As the output of the unit increases, the effect of the terminal temperature difference of the same stage of high pressure heater on the heat rate gradually becomes larger, and the effect of the terminal temperature difference of the same stage of low pressure heater on the heat rate gradually becomes smaller. [Conclusion] The research results are helpful for guiding the actual operation of the unit and improving the thermal economy of the unit.

[Introduction] In order to analyze the influence of excess air coefficient on the combustion stability of the furnace under the ultra-low load operation conditions of the thermal power unit, the unit is better guided to participate in peak shaving. [Method] In this paper, through in-depth analysis of boiler operation and heat transfer mechanism in the furnace, the combustion temperature of the furnace was characterized by the outlet temperature of the furnace, and as the index of combustion stability, the furnace exit smoke temperature model was built in MATLAB/SIMULINK. Taking a 300 MW thermal power generating unit as an example, the paper first selected several typical operating conditions. Then the similarity solving method was used to calculate the furnace exit smoke temperature and compare with the design data given by the boiler manufacturer. Finally the test calculation method was basically correct and then substituted into ultra-low load operation parameters which calculated the furnace exit smoke temperature corresponding to different excess air coefficients under deep peaking conditions. [Result] The simulation results show that the model calculates the furnace temperature and the design data given by the boiler manufacturer. The calculation error is less than ±15°C, and the calculation method is basically correct. It can be applied to the calculation of ultra-low load conditions. [Conclusion] As the load is reduced, the optimum excess air ratio that maximizes the flue gas temperature at the exit of the furnace is gradually increased. Therefore, under the condition of ultra-low load operation, the excess air coefficient can be appropriately increased within a certain range to increase the flue temperature of the furnace outlet, thereby improving the stability of the combustion of the boiler, and when the excess air ratio is less than 2.0, the value is higher, the temperature is higher.

Nonapoptotic forms of cell death can trigger sterile inflammation through the release of damage-associated molecular patterns, which are recognized by innate immune receptors. However, despite years of investigation, the mechanisms that initiate inflammatory responses after heart transplantation remain elusive. Here, we demonstrate that ferrostatin-1 (Fer-1), a specific inhibitor of ferroptosis, decreases the levels of pro-ferroptotic hydroperoxy-arachidonoyl- phosphatidylethanolamine, reduces cardiomyocyte cell death, and blocks neutrophil recruitment following heart transplantation. Inhibition of necroptosis had no effect on neutrophil trafficking in cardiac grafts. We extend these observations to a model of coronary artery ligation-induced myocardial ischemia reperfusion injury (IRI), in which inhibition of ferroptosis resulted in reduced infarct size, improved left ventricular (LV) systolic function, and reduced LV remodeling. Using intravital imaging of cardiac transplants, we show that ferroptosis orchestrates neutrophil recruitment to injured myocardium by promoting adhesion of neutrophils to coronary vascular endothelial cells through a TLR4/Trif/type I IFN signaling pathway. Thus, we have discovered that inflammatory responses after cardiac transplantation are initiated through ferroptotic cell death and TLR4/Trif- dependent signaling in graft endothelial cells. These findings provide a platform for the development of therapeutic strategies for heart transplant recipients and patients who are vulnerable to IRI following restoration of coronary blood flow., Introduction Ischemia reperfusion injury (IRI) following heart transplantation is a clinically significant form of sterile inflammation. IRI-mediated primary graft dysfunction complicates the postoperative course of up to 28% of human [...]

This study investigates the decision process of own-brand intrusion by contract manufacturers and their selection of invasion sales modes under the consideration of service quality disparities between brand manufacturers and contract manufacturers. Specifically, the study constructs a three-tier supply chain system comprising a brand manufacturer, a contract manufacturer, and an e-commerce platform. The equilibrium profits under different sales mode combinations are determined by using reverse induction methodology, and the optimal sales mode combinations are analyzed and compared. The study reveals that the decision process of contract manufacturers' own-brand invasion depends on the potential market demand. Furthermore, when brand manufacturers adopt the reselling mode, the service quality level does not affect the decision process of invasion sales modes. However, when brand manufacturers adopt the agency mode, contract manufacturers with low service quality levels are more suitable for invasion through the agency mode, whereas contract manufacturers with high service quality levels are better suited for invasion through the reselling mode. Additionally, for the equilibrium sales mode combination among members of the supply chain, it is observed that with lower commission rates, both brand manufacturers and contract manufacturers choose the agency mode, while with higher commission rates, both choose the reselling mode. When commission rates are moderate, brand manufacturers prefer the agency mode, whereas contract manufacturers prefer the reselling mode. [ABSTRACT FROM AUTHOR]

Understanding land use/cover change (LUCC) and landscape ecological risk change in the context of future climate warming can help adjust socio-economic development policies, optimize regional ecological security patterns, and promote green and low-carbon development on the one hand and provide important supplements and improvements for research in related fields on the other. Taking Urumqi as the study area, based on the Coupled Model Intercomparison Project Phase 6 (CMIP6) multi-modal ensemble data, we used the coupled system dynamics (SD) model and patch-generation land use simulation (PLUS) model to simulate land use change under three SSP-RCP scenarios in 2020–2060, and we predicted trends of landscape ecological risk change in this 40-year period by using the landscape ecological risk index (LERI). The results indicate that woodland and grassland significantly increase under the SSP126 scenario. Unused land is larger in the SSP245 scenario. The expansion trend of construction land toward cultivated land is most obvious in the SSP585 scenario; additionally, the area of water increases more distinctly in this scenario. The overall landscape ecological risk under the three SSP-RCP scenarios is reduced to different degrees; in particular, the risk level of urban built-up areas and nature reserves decreases remarkably, and the area of the highest risk zones of unused land is also gradually narrowed. By 2060, the average LERI under the SSP126 scenario is the lowest. The study findings can help relevant departments formulate reasonable urban development plans, which are of great theoretical and practical significance for guaranteeing regional ecological security. [ABSTRACT FROM AUTHOR]

The three principal fates of axillary meristem in flowering plants are growth (G), reproduction (R), and inactivity (I). The allocation relationships between each meristem and plant size in annual herbaceous plants tend to change with altered precipitation (P) patterns in arid and semiarid grasslands. Here, we examined the allometry and plasticity of meristem allocation in three dominant annual herbaceous plants: Setaria viridis, Corispermum macrocarpum, and Bassia dasyphylla in a semiarid sandy grassland in northern China. We determined the range of plant sizes for each of the three species in the following treatments: ambient environment (Amb), P increased by 30% (P[+]) and by 60% (P[++]), P decreased by 30% (P[−]) and by 60% (P[− −]), drought for 46 days from May 1st to June 15th (D1) and from July 1st to August 15th (D2). We found that meristem allocation to branching intensity increased while allocation to apical dominance decreased with increasing plant size under decreased precipitation and seasonal drought. Decreased precipitation and seasonal drought caused the slope of allometry of meristem allocation in the three species to be significantly different from 1. Plasticity of meristem allocation to G, R, and I in S. viridis tended to be significantly greater in August under P(+) and P(++) while in C. macrocarpum tended to be greater in July under P(−), P(− −), D1, and D2. Our findings are important components of an adaptive strategy in annual herbaceous plants throughout the development stage, which will contribute to predict their developmental dynamics in the semiarid sandy grassland under future climate change. [ABSTRACT FROM AUTHOR]

Polylactic acid (PLA) is a promising material due to its biodegradability and compatibility. However, the limited resistance to ultraviolet (UV) degradation of PLA composites hinders their use in automotive interior materials. In our previous work, we successfully prepared 3D printed filaments by combining KH550-treated micro-nano rice husk (MNRH) fibers with KH570-treated PLA, which exhibited favorable performance. This study aimed to investigate the effects of silane coupling agents, MNRH, and accelerated UV weathering time on the photodegradation behavior of 3D printed PLA-matrix composites reinforced with MNRH. Scanning electron microscopy (SEM), Fourier transform infrared (FTIR), thermogravimetric analysis (TGA), and differential scanning calorimetry (DSC) were utilized to characterize the 3D printed PLA-matrix composites. Furthermore, an exponential equation between tensile strength and UV weathering time was established, providing theoretical guidance for predicting the service life of automotive interior materials based on PLA composites. The morphological characterization experimental results indicate that with prolonged UV aging time, both PLA and RH6-KH550/KH570 composite materials transitioned from transparency to translucency. This transition can be attributed to the rupture of polylactic acid molecular chains and chemical bonds during the UV aging process. FTIR test results revealed the formation of carboxylic acid in the composite, and the reduction of C = O absorption intensity indicated that MNRH and silane coupling agents exhibited a stabilizing effect on the UV durability of the RH6-KH550/KH570 composite. TGA and DSC results indicated that KH550 and KH570 delayed the photodegradation rate of PLA-matrix composites. [ABSTRACT FROM AUTHOR]

Drought seriously endangers the development of agro‐pastoral ecotone in arid and semi‐arid regions. However, drought evolution characteristics of semi‐arid sandy grassland and its drivers are not well understood in the complex climate change context. Thus, in this paper, the revised standardized precipitation evaporation indices on one‐month (SPEI‐1) and growing‐season (SPEI‐6) scale, flash drought and dry spells (DS) were calculated as drought indicators, and the temporal variabilities and meteorological drivers of drought in Horqin Sandy Land during the growing period (April–September) from 2007 to 2021 were studied. The results showed that SPEI‐1 and SPEI‐6 exhibited negative trends and periodic change. This drought aggravation was manifested in increased grades and numbers of drought months. Flash droughts can occur every month during the growing season. And its occurrence was not only positively correlated with all drought events in frequency but also synchronized in time. The increased number of DS showed an asymmetrical shift towards 7‐day‐and‐longer DS. SPEI sensitivity to precipitation (P) was noticeably higher than to atmospheric evapotranspiration demand (AED) at both monthly and growing season scales. SPEI sensitivity to AED was modulated by P amounts, which was higher during low P period. Apart from the amounts of P and AED, their temporal variability also strongly determined how they affect the drought severity. P was also the main driver for flash drought and long DS, but AED with larger amount and higher variability is the reason for their aggravation. Our results demonstrate the complexity of drought intensification in semi‐arid sandy grasslands and highlight the important role of AED anomalies in it. [ABSTRACT FROM AUTHOR]

Using biodegradable blending materials is one of the most effective ways to address plastic pollution but it is hindered by its poor interfacial interaction along with high costs. Herein, an envirionmentally friendly filler, camellia seed powder (CSP)−a byproduct of camellia seed after defatting, is reported, which is first served as a compatibilizer in polylactic acid (PLA)/polybutylene succinate (PBS) blends without any other aids or complicated pretreatment, effectively toughening the PLA/PBS blends due to a better interfacial interaction. The results show that the toughness of composites increases with CSP content. With the addition of 30 phr CSP, its impact strength and elongation at break increase by 44.31% and 148.42%, respectively, as compared with the blend without CSP. The combined effects of improved interfacial bonding, reduced particle size of PBS and efficient stress transfer are responsible for the toughness enhancement. The compatibilization mechanism is proposed that ─COOH groups in PLA and PBS react with ─NH2 in CSP. The above finding of CSP as a compatibilizer provides a facile and inexpensive strategy in the fabrication of high‐performance biodegradable materials. [ABSTRACT FROM AUTHOR]

In this study, the vegetation and soils of different desertification landscapes (sandy grassland, and fixed, semi‐fixed, semi‐mobile, and mobile dunes) in the Hulun Buir Sandy Land were examined to quantify the impacts of desertification on plants, soils, and microbes, and the key limiting factors of restoration. Desertification caused soil quality to decline and led to an imbalance of nitrogen (N) and phosphorus (P) supplies (N:P ratios decreased significantly from 3.55–1.8, p < 0.05). Desertification did not change the stoichiometric relationships among plant carbon (C), N, and P at a community level, but promoted redistribution of nutrients from roots to aboveground tissues. The aboveground biomass N and P increased by 9.8% and 39.3%, respectively from grassland to mobile dunes, but these of the underground biomass decreased by 26.1% and 37.7%, respectively. N limitation (plant N:P < 10) occurred at the community level. Desertification led to the change of dominant species from perennial herbs to annual psammophytes, and plant diversity (from 1.15–0.79) and productivity (from 880.6 to 128.6 g m−2) first increased slightly (p > 0.05) and then decreased sharply (p < 0.05) with increasing desertification, but with no significant (p > 0.05) change of the microbial community. Redundancy analysis showed that the main environmental drivers were the soil N:P (with an explanation of 29.6%), followed by pH, electrical conductivity, and the soil's fine particles (with a total explanation of 24.3%). Based on these results, three reference frames were proposed for the restoration of the near‐original vegetation community. [ABSTRACT FROM AUTHOR]

Efficient and spatiotemporally controllable cleavage of deoxyribonucleic acid (DNA) is of great significance for both disease treatment (e.g. tumour, bacterial infection, etc) and molecular biology applications (e.g. gene editing). The recently developed light-induced cleavage strategy based on catalytic nanoparticles has been regarded as a promising strategy for DNA controllable cleavage. Although the regulation based on orthogonal light in biomedical applications holds more significant advantages than that based on single light, nanoparticle-mediated DNA cleavage based on orthogonal light has yet to be reported. In this article, for the first time, we demonstrated an orthogonal light-regulated nanosystem for efficient and spatiotemporal DNA cleavage. In this strategy, tungsten oxide (WO3) nanoparticles with photochromic properties were used as nano-antennae to convert the photoenergy from the orthogonal visible light (405 nm) and near-infrared light (808 nm) into chemical energy for DNA cleavage. We verified that only the orthogonal light can trigger high cleavage efficiency on different types of DNA. Moreover, such an orthogonal light-response nano-system can not only induce significant apoptosis of tumour cells, but also effectively eliminate bacterial biofilms. [ABSTRACT FROM AUTHOR]

Bacterial infections are a serious threat to human health, and the rapid emergence of bacterial resistance caused by the abuse of antibiotics exacerbates the seriousness of this problem. Effectively utilizing natural products to construct new antimicrobial strategies is regarded as a promising way to suppress the rapid development of bacterial resistance. In this paper, we fabricated a new type of natural antibacterial patch by using a natural active substance (allicin) as an antibacterial agent and the porous structure of the white pulp of pomelo peel as a scaffold. The antibacterial activity and mechanisms were systematically investigated by using various technologies, including the bacteriostatic circle, plate counting, fluorescence staining, and a scanning electron microscope. Both gram-positive and negative bacteria can be effectively killed by this patch. Moreover, this natural antibacterial patch also showed significant anti-skin infection activity. This study provides a green approach for constructing efficient antibacterial patches. [ABSTRACT FROM AUTHOR]

Overgrazing in semiarid grassland is a major cause of vegetation degradation. Understanding the changes in seedling patterns driven by grazing is crucial to unveiling mechanisms of plant community regeneration and succession in grazed grassland. However, the dynamics of seedling emergence and species diversity under grazing are rarely studied. This study used periodical field investigation to examine the variation in seedling emergence, plant diversity, species composition, and seedling survival of herbaceous plants under four grazing intensities, including light (LG), moderate (MG), heavy (HG), and non‐grazed (NG), in a semiarid sandy grassland. The results showed that seedling number and density were significantly higher in HG plots, while the seedling survival rate was significantly lower in HG, and that seedling emergence dynamics varied with grazing. Seventy‐five percent of the seedlings in HG emerged during early spring in April, while approximately 50% of the seedlings in LG, MG, and NG emerged in May. Differences in species richness and diversity varied with growth stages and the diversity was always higher in LG than in other grazing habitats during the main growing season. Annual forb seedlings increased while annual grass seedlings decreased after grazing with no perennial grass seedlings in HG. Our study suggests that high seedling emergence but low seedling survival rate, and simple species composition especially the disappearance of perennial plants caused by HG may be an important factor leading to vegetation degradation in the semiarid grazed grassland. [ABSTRACT FROM AUTHOR]

Seedlings are a crucial part of the plant community and the basis of vegetation restoration and regeneration. Grazing and climate change are two main factors contributing to vegetation changes in semiarid grasslands. However, the effects of grazing on seedling emergence with rainfall variation are not clearly understood. This study aimed to address how seedling abundance and the emergence dynamics of annuals respond to grazing with rainfall changes in different years. We conducted a seedling investigation experiment in a grassland along a grazing intensity gradient (light grazing—LG; moderate grazing—MG; heavy grazing—HG) in contrasting wet and dry years. The results showed that MG increased the seedling richness of grasses and forbs in the wet year, but increasing grazing resulted in a decline in forb richness in the dry year. Seedling abundance of grasses was enhanced under MG, while seedling abundance of forbs was higher under HG. The monthly emergence dynamics were generally in a single peak pattern, but the peak time of seedling emergence for forbs advanced under HG. Seedling abundance of whole annuals increased with grazing in the wet year but was much higher under MG in the dry year. Our results suggest that more judicious grazing management based on rainfall variation and functional composition of the plant community should be undertaken to facilitate grassland restoration. [ABSTRACT FROM AUTHOR]

In this study, micro‐nano rice husks (MNRH) fibers are compounded in polylactic acid (PLA) to produce 3D‐printed filaments by using melt blending method, and some properties of the printed samples of different surface treatment processes are measured. Two silane coupling agents of KH550 and KH570 are severally used on MNRH and PLA to mitigate the surface quality deficiencies for an intimate interfacial bond. Microstructural analysis shows that the MNRH fibers of the composites treated by silane coupling agent have a better dispersing performance. Fourier transform infrared illustrates that the KH550 and KH570 are successfully grafted onto PLA and MNRH fibers. Thermogravimetric analysis (TGA/DSC) suggests that the thermostability and crystallinity of the composites treated by silane coupling agents are enhanced. Water absorption experiments shows that the water resistance of the composites is greatly increased by KH550 and KH570. In comparison with pure PLA, the tensile strength, tensile modulus, bending strength and bending modulus of the 6 wt.% MNRH/PLA composites that treated by KH550 and KH570 are enhanced by 83%, 98%, 54%, and 61%, respectively. The composites treated by KH550 and KH570 demonstrates the best performance, suggesting that they have great potential for use as an environmentally friendly alternative material in automotive interiors. [ABSTRACT FROM AUTHOR]

Plant fine root turnover is a continuous process both spatially and temporally, and fine root decomposition is affected by many biotic and abiotic factors. However, the effect of the living roots and the associated mycorrhizal fungal mycelia on fine root decomposition remains unclear. The objective of this study is to explore the influence of these biotic factors on fine root decomposition in a semi-arid ecosystem. In this study, we investigated the effect of fine roots and mycelia on fine root decomposition of a pioneer shrub (Artemisia halodendron) in Horqin sandy land, northeast China, by the ingrowth core method combined with the litterbag method. Litterbags were installed in cores. Results showed that core a allowed the growth of both fine roots and mycelia (treatment R + M), core b only allowed the growth of mycelia (treatment M), and in core c the fine root and mycelia growth were restricted and only bulk soil was present (treatment S). These findings suggest that the process of root decomposition was significantly affected by the living roots and mycelia, and carbon (C) and nitrogen (N) concentration dynamics during root decomposition differed among treatments. Mycelia significantly stimulated the mass loss and C and N release during root decomposition. Treatment R + M significantly stimulated the accumulation of soil total C, total N, and organic N under litterbags. The mycelia significantly stimulated the accumulation of the inorganic N (ammonium-N and nitrate-N) but the presence of fine roots weakened nitrate-N accumulation. The presence of living roots and associated mycelia strongly affected the process of root decomposition and matter release in the litter-soil system. The results of this study should strengthen the understanding of root-soil interactions. [ABSTRACT FROM AUTHOR]