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Nondimensionalization, a theoretical approach for establishing interconnections among parameters within a set of equations, has proven to be an effective tool for the analysis of atmospheric turbulence. By applying nondimensionalization to turbulence equations, a concise form of dimensionless turbulence functions can be obtained. This process also yields several dimensionless parameters, defined as combinations of characteristic scales. From the dimensionless tensor B and vector β θ introduced in this study, the characteristic length scale, z s , can be defined as an alternative of length scale in similarity theories. Using the data from observational station in Horqin Sandy Land, quantified verifications of similarity relationships are carried out. The dimensionless parameters derived from nondimensionalization is not only in accordance with traditional turbulence theories but also facilitate the derivation of relationships among other dimensionless parameters. This reveals new similarity relationships that supplement the Monin–Obukhov theory. Under conditions of flat terrain and steady motions, the new length scale gives rise to similarity relationships exhibiting "4/3" exponential and near-linear patterns, which are associated with turbulent transport. These results make it possible to obtain the turbulent fluxes directly from the statistics of meteorological elements, even in stable stratifications. Consequently, the method of nondimensionalization can be taken as a reference in parameterization schemes of turbulence and climate models, and is fruitful in prospect of further study on atmospheric turbulence. [ABSTRACT FROM AUTHOR]

A month-long numerical simulation investigates summertime sea breezes in the North China Plain (NCP), occurring predominantly from late afternoon to night-time and penetrating over 100 km inland. The key factor driving this phenomenon is identified as a persistent lee-side cyclone in the western NCP, formed by dynamic interactions between upper-air north-westerly winds and mountain barriers upstream. Throughout a summer month, the lee-side cyclone varies in strength diurnally, significantly influencing sea breeze development. A case study of high-resolution simulation provides detailed insights into the wind field and the evolving lee-side cyclone structure. In the evening peak, three sectors of air flows—westerly, southerly, and south-easterly—encompass the cyclone core, demarcated by fronts with sharp gradients in temperature, moisture, and wind speed and direction. As the south-easterly sea breeze intensifies, it swiftly advances inland along the mountainside, forming an arch-like intrusion path. With the weakening and south-westward movement of the lee-side cyclone, the sea breeze transforms into an inertial current, guided further south-westward. The vertical structure of the sea breeze is revealed, including the depth of its moisture-layer and its uplifting effect on the warmer inland air mass at the cyclone core. The interaction between the lee-side cyclone and sea breeze facilitates the transport of substantial water vapor from the Bohai Sea coastline to the interior of the NCP. These findings provide new insights into the summertime sea breeze mechanism in the NCP, with implications for local weather patterns, water vapor budget, and air pollutant transport. [ABSTRACT FROM AUTHOR]

Through comparing the distribution of blank holder force (BHF) and stress-strain curve along the radial direction, there has been good forming capability and adaptability in deep drawing with the electro-permanent magnetic (EPM) blank holder (EPMBH) technique. However, whether the BHF technique is applicable for non-ferromagnetic materials has yet to be researched. In the paper, taking 08-Al steel and H62 copper plates as examples, the drawability of ferromagnetic and non-ferromagnetic sheets with EPMBH is investigated. Moreover, a series of confirmatory tests were carried out based on numerical analysis. It found that similar to the deep drawing with ferromagnetic slab, there is slight attenuation on the holding effect for non-ferromagnetic sheets, and the effect of gap on the magnetic attraction caused by the magnetic properties of the plate first increases sharply and then slowly decreases, while its possible failure modes are also wrinkling and rupture due to insufficient BHF and excessive drawing height, respectively. In the experiment, flawless deep-drawing workpieces can be obtained with EPMBH, indicating that EPMBH could meet the forming requirement for ferromagnet and non-ferromagnetic plates and can be controllably adjusted through altering the excitation current of the EPMBH device. The experiment result shows that the optimal excitation current is 14 A for ferromagnetic steel plate and 13 A for non-ferromagnetic copper plate with the same diameter of 110 mm and thickness of 0.8 mm. [ABSTRACT FROM AUTHOR]

In this paper, a new segmental blank holder technique was developed. The blank holder force (BHF) was applied on sheet metal independently and effectively by the binder which was divided into double rings. The principle of holding was derivatized by theoretical formulas, thereby proving that the BHF distribution applied by the new binder is more reasonable. Furthermore, combined with numerical simulation, it can be found that the wrinkling was better suppressed. Finally, the effectiveness of the segmental blank holder technique was proven by a series of experiments with AA5754 plate. It is verified that the flange wrinkling was demonstrated to be more eliminated than that using the single blank holder. Compared with 1:2 and 2:1, when the distribution ratio between the outer ring and the inner ring is 1:2 (the applied BHF is 6.9 kN), there has a better-forming quality. [ABSTRACT FROM AUTHOR]

Long noncoding RNAs (lncRNAs) play a role in the emergence and progression of several human tumors, including luminal B breast cancer (BC). The biological functions and potential mechanisms of lncRNA myocardial infarction-associated transcripts (MIAT) in luminal B BC, on the contrary, are unknown. In this work, we used UALCAN database analysis to find high expression of lncRNA MIAT in luminal BC tissues and also confirmed high levels of lncRNA MIAT expression in luminal B BC tissues and cells. In vitro knockdown of MIAT inhibited the proliferation, migration, and invasion of BT474 cells. In addition, we found that miR-150-5p levels were significantly reduced in luminal B BC specimens and cells, and miR-150-5p levels were significantly increased when MIAT was knocked down. And TIMER database analysis showed that MIAT was positively associated with PDL1. Through bioinformatic tools and in vitro experiments, lncRNA MIAT could function as a competitive endogenous RNA (CeRNA) to further regulate programmed cell death ligand 1 (PDL1) expression by directly sponging miR-150-5p. In conclusion, our data suggest that MIAT, an oncogene, may sponge miR-150-5p to regulate PDL1 expression and affect proliferation, migration, and invasion in luminal B BC in vitro. [ABSTRACT FROM AUTHOR]

Preharvest sprouting (PHS) is an undesirable trait that decreases yield and quality in rice production. Understanding the genes and regulatory mechanisms underlying PHS is of great significance for breeding PHS-resistant rice. In this study, we identified a mutant, preharvest sprouting 39 (phs39), that exhibited an obvious PHS phenotype in the field. MutMap+ analysis and transgenic experiments demonstrated that OsAAH, which encodes allantoate amidohydrolase, is the causal gene of phs39 and is essential for PHS resistance. OsAAH was highly expressed in roots and leaves at the heading stage and gradually increased and then weakly declined in the seed developmental stage. OsAAH protein was localized to the endoplasmic reticulum, with a function of hydrolyzing allantoate in vitro. Disruption of OsAAH increased the levels of ureides (allantoate and allantoin) and activated the tricarboxylic acid (TCA) cycle, and thus increased energy levels in developing seeds. Additionally, the disruption of OsAAH significantly increased asparagine, arginine, and lysine levels, decreased tryptophan levels, and decreased levels of indole-3-acetic acid (IAA) and abscisic acid (ABA). Our findings revealed that the OsAAH of ureide catabolism is involved in the regulation of rice PHS via energy and hormone metabolisms, which will help to facilitate the breeding of rice PHS-resistant varieties. [ABSTRACT FROM AUTHOR]

DNA methylation is a kind of epigenetic modification regulated by DNA methyltransferases and DNA demethylases. Here, the influences of DNA methylation inhibitor 5-aza-2'-deoxycytidine (5-azadC) combined with plant hormones [abscisic acid (ABA), methyl jasmonate (MeJA), and gibberellic acid (GA3)] and small gaseous signal molecules [(nitric oxide (NO), hydrogen sulfide (H2S), and hydrogen gas (H2)] on the tomato (Solanum lycopersicum) seedlings growth were explored. Moreover, the expression levels of DNA methyltransferases and demethylases under plant hormones and small gaseous molecules were detected. We found that ABA and MeJA restrained tomato seedling growth, and GA3, NO, H2S, and H2 promoted seedling growth. Nevertheless, 5-azadC treatment retarded the effects of these plant growth regulators mentioned above. Moreover, ABA boosted SlDRM5 expression, whereas GA3 and MeJA treatments inhibited the expression. Sodium hydrosulfide and hydrogen-rich water treatments affected SlDRM5 expression. Moreover, MeJA increased the quantity of SlDML1 transcripts from 3 to 24 h, while other therapies decreased the quantity. It is interesting to note that GA3 expressively induced SlMET1 and SlDML2 expression. Hence, DNA methylation may be essential for plant growth and is controlled by phytohormones and gaseous signal channels. The findings above offer fresh perspectives on how DNA methylation inhibitor reacts to different plant growth regulators. [ABSTRACT FROM AUTHOR]

Exact solutions of spherically symmetric black hole and gravitational wave are explored in f(R) gravity in arbitrary dimension. We find two exact solutions for the radiation and absorption of null dust. In the framework of general relativity, the Birkhoff theorem strictly forbids the existence of spherical gravitational waves in vacuum space. We find spherical non-perturbative gravitational waves, which are shear-free, twist-free, but expanding. [ABSTRACT FROM AUTHOR]

The Johannsen black hole (BH) is a generic rotating BH admitting three constants of motions (energy, angular momentum, and Carter constant) and is characterized by four deviation parameters besides mass and spin, which could be a model-independent probe of the no-hair theorem. We systematically study the dynamics of null particles around Johannsen BH, revealing the effects of the deviation parameters on the BH shadow as well as the effects of spin. By using the shadow boundaries of M87* and SgrA*, for the first time, the deviation parameters of those BHs are constrained. The detailed results depend on the spin a and inclination angle θ0. Assuming a = 0.2 and θ0 = 15°, the deviation parameter α13 are constained within ~ [−3.5, 6] for M87* observation and [−3, 0.5] for SgrA* observation. We also show the images of a Johannsen BH surrounded by a Page-Thorne thin accretion disk observed by a remote observer with a ray-tracing method and discuss the effects of the deviation parameters on deforming the accretion disk image, which could be tested by observations with higher sensitivities in the future. [ABSTRACT FROM AUTHOR]

The development of oceanic remote sensing artificial intelligence has made possible to obtain valuable information from amounts of massive data. Oceanic internal waves play a crucial role in oceanic activity. To obtain oceanic internal wave stripes from synthetic aperture radar (SAR) images, a stripe segmentation algorithm is proposed based on the TransUNet framework, which is a combination of U-Net and Transformer, which is also optimized. Through adjusting the number of Transformer layer, multi-layer perceptron (MLP) channel, and Dropout parameters, the influence of over-fitting on accuracy is significantly weakened, which is more conducive to segmenting lightweight oceanic internal waves. The results show that the optimized algorithm can accurately segment oceanic internal wave stripes. Moreover, the optimized algorithm can be trained on a microcomputer, thus reducing the research threshold. The proposed algorithm can also change the complexity of the model to adapt it to different date scales. Therefore, TransUNet has immense potential for segmenting oceanic internal waves. [ABSTRACT FROM AUTHOR]

This research is aimed to adjust blank holder force (BHF) in different flange areas to eliminate wrinkles and cracks on rectangular box deep drawing products. The calculating formulas of the critical BHF in the flange area are derived by using the energy method. And a wrinkle model parameter m effect on the critical BHF is analyzed. It is shown that the critical BHF decreases with decreasing m as the same wrinkle height. A steel sheet of SPCC grade, thickness of 0.6 mm, is used in the finite element simulation study. It is shown that the segmental blank holder technique is better than the conventional one. Finally, compared to the application of the single blank holder, BHF can be quite effective for preventing the occurrence of cracking and increasing the formability of deep drawing. [ABSTRACT FROM AUTHOR]

To date, the characteristics of the low-level jets (LLJs) that appear below 300 m, referred to in this study as tower-level LLJs (T-LLJs), have remained unidentified. The results in this study show that approximately 22% of LLJs in Tianjin appear below 300 m, indicating that greater attention should be given to T-LLJs. Thus, the characteristics of T-LLJs in Tianjin are investigated using data obtained from a wind-profile radar and a 255-m high meteorological tower. The results show that T-LLJs frequently occur during the transition from the warm season to the cold season and prefer to appear at night. Compared to the LLJs that appear between 300 and 1000 m, T-LLJs exhibit distinct monthly and diurnal variations, likely attributable to specific underlying causes. The case study suggests that the generation of T-LLJs can be partly attributed to inertial oscillation. Moreover, sensitivity tests indicate that the land‒sea thermal contrast is one of the main causes of T-LLJs, and that urban heat islands (UHIs) exert nonnegligible influence on T-LLJs in Tianjin. In addition, since UHIs are mainly nocturnal phenomena, the impacts of nocturnal LLJs on UHIs are investigated. The results show that nocturnal LLJs contribute to enhance turbulent mixing and heat transport, which can weaken atmospheric stability near the surface. Consequently, a nocturnal UHI is always weaker when it occurs concurrently with a LLJ, as opposed to occurring without a LLJ. [ABSTRACT FROM AUTHOR]

The North China Plain (NCP) is troubled by severe haze pollution and the evolution of haze pollution is closely related to the atmospheric boundary layer (ABL). However, experimental and theoretical studies on the physical-chemical processes of the ABL in the NCP are lacking, with many scientific problems to be addressed. To solve these problems, the Comprehensive Observation on the Atmospheric boundary layer Three-dimensional Structure (COATS) during haze pollution was carried out in the NCP from 2016 to 2020. The COATS experiment adopted a "point-line-surface" spatial layout, obtaining both spatial-temporal profiles of the meteorological and environmental elements in the ABL and the turbulent transport data of fine particulate matter (PM2.5) in winter and summer. The research achievements are as follows. The spatial-temporal distribution characteristics of the ABL structure and PM2.5 concentrations in the NCP were determined. The typical thermal structure of persistent heavy haze events and the pollutant removal mechanism by low-level jets were revealed. It was determined that the spatial structure of the ABL adjusted by the Taihang Mountains is responsible for the heterogeneous distribution of haze pollution in the NCP, and that mountain-induced vertical circulations can promote the formation of elevated pollution layers. The restraints of the atmospheric internal boundaries on horizontal diffusion of pollutants were emphasized. The contribution of the ABL to haze pollution in winter and summer was qualitatively compared and quantitatively estimated. The turbulent transport nature behind the relationship between the atmospheric boundary layer height (ABLH) and surface PM2.5 concentrations was analyzed. The concept of "aerosol accumulation layer" was defined, and the applicability of the material method in determining ABLH was clarified. A measurement system for obtaining the turbulent flux of PM2.5 concentrations was developed, and the turbulence characteristics of PM2.5 concentrations were demonstrated. The COATS experiment is of great theoretical significance for thoroughly understanding the physical mechanisms of the ABL during haze pollution and filling the knowledge gap on the impacts of the ABL three-dimensional structure on haze pollution. The results of this study are conducive to the improvement and development of ABL parameterization schemes and serve as a scientific basis for formulating regional pollution prevention and control measures. [ABSTRACT FROM AUTHOR]

Key message: Two causal OsTTL and OsSAPK1genes of the key locus qNL3.1 significantly associated with seed germination under salt stress were identified via a genome-wide association study, which could improve rice seed germination under salt stress. Rice is a salt-sensitive crop, and its seed germination determines subsequent seedling establishment and yields. In this study, 168 accessions were investigated for the genetic control of seed germination under salt stress based on the germination rate (GR), germination index (GI), time at which 50% germination was achieved (T50) and mean level (ML). Extensive natural variation in seed germination was observed among accessions under salt stress. Correlation analysis showed significantly positive correlations among GR, GI and ML and a negative correlation with T50 during seed germination under salt stress. Forty-nine loci significantly associated with seed germination under salt stress were identified, and seven of these were identified in both years. By comparison, 16 loci were colocated with the previous QTLs, and the remaining 33 loci might be novel. qNL3.1, colocated with qLTG-3, was simultaneously identified with the four indices in two years and might be a key locus for seed germination under salt stress. Analysis of candidate genes showed that two genes, the similar to transthyretin-like protein OsTTL and the serine/threonine protein kinase OsSAPK1, were the causal genes of qNL3.1. Germination tests indicated that both Osttl and Ossapk1 mutants significantly reduced seed germination under salt stress compared to the wild type. Haplotype analysis showed that Hap.1 of OsTTL and Hap.1 of OsSAPK1 genes were excellent alleles, and their combination resulted in high seed germination under salt stress. Eight accessions with elite performance of seed germination under salt stress were identified, which could improve rice seed germination under salt stress. [ABSTRACT FROM AUTHOR]

A novel sparse LMS algorithm for the sparse system identification is proposed to reduce the complexity of the existing algorithms. The proposed algorithm discards W(n) when the value of the current weight vector is within a certain range. The algorithm also optimizes the iterative update equation by using only the product term to calculate the value of W(n+1). The hardware implementation shows that the total logic elements number of the proposed algorithm is 60.06% less than the latest l0-ILMS algorithm, while the performance is nearly the same. [ABSTRACT FROM AUTHOR]

We find a class of novel black holes in higher derivative theory. The novel black holes follow behavior of Schwarzschild ones at large mass limit, while dramatically differentiate from Schwarzschild ones for little holes because of the effects which may root in quantum gravity. The temperature of the hole takes maximum for a specific mass, which is related to the new sale introduced in the higher derivative theory, and goes to zero at little mass limit. This property leads to a significant observation that the novel black hole may be a candidate for dark matters evading constraint from γ-ray burst. [ABSTRACT FROM AUTHOR]

Primary work on the planetary boundary layer (PBL) climatic features and associated air pollution in Beijing was carried out based on a 40-year dataset. The main results are identified as follows. The annual mean PBL height was 906 m (1455 m in daytime and 357 m in nighttime). Within the PBL, the average potential temperature, specific humidity, and wind speed were 287.3 K, 5.1 g kg−1, and 6.5 m s−1. Significant seasonal variations were observed in the PBL variables, leading to distinct pollutant diffusion conditions. The PM2.5 concentrations varied seasonally, with a high value in winter (97 µg m−3) and a low value in summer (74 µg m−3). The summertime PM2.5 was closely related to the local emission intensity (R = 0.79) and declined with a reduction in the emission intensity, while the winter PM2.5 showed large interannual variabilities and trends, relying more on the PBL conditions. A comparison of polluted and clean winters was performed, revealing that polluted winters were associated with a warmer layer above the PBL that inhibited the development of the PBL (933 m vs. 1283 m, daily maximum height for polluted vs. clean winters) and led to a humid (1.4 g kg−1 vs. 0.8 g kg−1) and weak wind (5.8 m s−1 vs. 8.2 m s−1) layer within the PBL. In terms of synoptic impacts, the warm advection above the PBL (0.07 K h−1) and subsidence heating (0.21 K h−1) near the top of the PBL contributed to the occurrence of a stable and polluted PBL. [ABSTRACT FROM AUTHOR]

This research aims to utilize quarterly global VAR data from April 1, 2020, to September 30, 2021, to assess the influence of the economic recovery of China following the COVID-19 outbreak on global economies. China is one of the first big economies globally to show indications of recovery following the COVID-19 pandemic. The nation's economic growth has the biggest long-term influence on middle-income nations (0.17%) followed by low- and middle-income economies (0.16%) and high-income economies (0.16%) (0.15%). The chain reaction of China's economic growth is most visible in high-income nations (0.11–0.45%), followed by middle-income countries (0.08–0.33%) and low-income countries (0.02–0.05%). Our findings show that the post-COVID-19 economic rebound in China will mostly benefit middle-income nations, with low- and middle-income countries following closely after. After COVID-19, the influence of the economic recovery of China is most visible in the rise of energy consumption in high-income nations, followed by middle-income economies. It is also worth noting that the influence of China's economic expansion on low- and middle-income economies does not always imply a rise in energy consumption. Overall, China's economic recovery has a significantly stronger influence on other countries' economic development than other countries' energy consumption has on other economies' growth. [ABSTRACT FROM AUTHOR]

The large-aperture scintillometer (LAS) has been widely used in the estimation of sensible heat fluxes (H) on various land surfaces, but they are seldom used in deserts with dune topographies. Here, an LAS was deployed in the Taklimakan Desert for about two weeks to investigate its ability to estimate H over the dune topography in the desert and its impact on the surface energy balance. We estimated the LAS and eddy covariance (EC) fluxes using standard methods, as well as H directly calculated by the EC system via a spectral fitting method. We conducted a series of sensitivity tests to investigate the scintillometer-based heat flux estimation uncertainties by considering surface and meteorological parameters and surface-layer similarity structure functions. In addition, the imbalance problem in the surface energy budget was examined using the measurements. Desert areas are different from other land surfaces in that they are characterized by a high sensible heat flux. It was found that the LAS had good performance in the Taklimakan Desert and could capture more low-frequency turbulence. Also, the spectral fitting method used on the data obtained with the EC system could capture more low-frequency turbulence compared to the direct calculations made by the EC system. The H values obtained by the LAS (HLAS) were overestimated by about 11.6% relative to those measured by the EC system (HEC), and the HEC values obtained by the spectral fitting method were overestimated by about 12.1% relative to them being directly calculated by the EC system. Large and dispersed values of HLAS/HEC appeared with smaller values of rwT (the correlation coefficient) (i.e., 0.1–0.3), and the large ratio of HLAS/HEC might be related to a predominance of low-frequency motions in stable stratification. However, the H values estimated by the LAS had great uncertainties in the case of high wind speeds and weak winds at night. The main source of uncertainty in the estimation of H by the LAS was the use of the different surface parameters (e.g., the Bowen ratio, roughness length, and LAS effective height) and the different forms of fT(ζ) from the Monin–Obukhov similarity theory (MOST). Different from the flat surfaces in desert areas, dune topography affected the use of fT(ζ) of MOST by 37%. MOST can improve the estimation of H, and then improve the calculation of the surface energy balance ratio (EBR). [ABSTRACT FROM AUTHOR]

We make a first principle study of gravitational pressure in cosmic thermo- dynamics. The pressure is directly derived from the unified first law, in fact the Einstein field equation in spherically symmetric spacetime. By using this pressure, we obtain the thermodynamics for the FRW universe, especially presenting the gravitational equation of state for the FRW spacetime itself, i.e. P = P (RA, T) for the first time. Furthermore, we study the Joule-Thomson expansion as an application of the thermodynamic equation of state to find the cooling-heating property of the FRW universe. We demonstrate that there is an inversion temperature for a FRW universe if its enthalpy ℋ is negative. These investigations shed insights on the evolution of our universe in view of thermodynamics. [ABSTRACT FROM AUTHOR]

We define thermodynamic pressure P by work density W as the conjugate quantity of thermodynamic volume V from field equation. We derive the equations of state P=P(V, T) for the Friedmann–Robertson–Walker (FRW) universe in Einstein gravity and a modified gravity respectively. We find that the equation of state from Einstein gravity shows no P-V phase transition, while the equation of state from the modified gravity does, where the critical exponents are the same as those in mean field theory. [ABSTRACT FROM AUTHOR]

In this paper, a novel multi-ring blank holder technique is developed. The blank holding force (BHF) provided by each ring can be independently and effectively applied on all radial regions. The principles and advantages of the multi-ring technique are first explained and analyzed by theoretical derivation, stress analysis, and forming simulation. The results indicate that the distribution of the blank holder force per unit area (FUA) applied by the new blank holder technique is more reasonable than using the conventional single blank holder and can better suppress the wrinkles. Finally, the effectiveness of the multi-ring blank holder technique is proven by a deep drawing experiment of the 08Al plate. It was verified that due to the reasonable FUA distribution, the use of the blank holder technique can suppress the wrinkles on the flange very well. [ABSTRACT FROM AUTHOR]

Photocatalysis is considered to be one of the possible routes to solve energy crises at a low cost. Graphitic-C3N4 combined with other semiconductors at the nanoscale has demonstrated a promising potential in photocatalysis application owing to the heterojunction configuration. In this study, Ag/g-C3N4/CuNb2O6-4 (mass ratio of CuNb2O6 to g-C3N4 = 1:4) composites were prepared by photo-deposition of Ag particles on the hydrothermally synthesized g-C3N4/CuNb2O6-4 composites. The microstructure, morphology, and light absorption property of the photocatalysts were characterized by X-ray diffractometry, scanning electron microscopy, transmission electron microscopy, X-ray photoelectron spectroscopy, and UV–Vis diffuse reflectance spectroscopy. The photocatalytic properties of photocatalysts and active species responsible for the degradation of RhB dye under visible light were investigated. After loading Ag particles on the g-C3N4/CuNb2O6-4 composites, the resulting Ag/g-C3N4/CuNb2O6-4 composites show a bandgap of ~ 2.31 eV and a significant increase in photocatalytic efficiency. In particular, the photocatalytic activity of 11% Ag/g-C3N4/CuNb2O6-4 composite (Ag mass fraction = 11%) is nearly seven times that of orthorhombic CuNb2O6 and 3.8 times that of g-C3N4/CNO-4 composite. The Z-scheme heterojunction has been successfully formed in the Ag/g-C3N4/CuNb2O6-4 composites and it enhances the photocatalytic performance significantly with the best degradation efficiency of 88% after 2 h. [ABSTRACT FROM AUTHOR]

Terrestrial ecosystems in China receive the world's largest amount of reactive nitrogen (N) deposition. Recent controls on nitrogen oxides (NOx = NO + NO2) emissions in China to tackle air pollution are expected to decrease N deposition, yet the observed N deposition fluxes remain almost stagnant. Here we show that the effectiveness of NOx emission controls for reducing oxidized N (NOy = NOx + its oxidation products) deposition is unforeseen in Eastern China, with one-unit reduction in NOx emission leading to only 55‒76% reductions in NOy-N deposition, as opposed to the high effectiveness (around 100%) in both Southern China and the United States. Using an atmospheric chemical transport model, we demonstrate that this unexpected weakened response of N deposition is attributable to the enhanced atmospheric oxidizing capacity by NOx emissions reductions. The decline in N deposition could bear a penalty on terrestrial carbon sinks and should be taken into account when developing pathways for China's carbon neutrality. Recent vigorous controls in anthropogenic nitrogen oxide emissions in China cannot result in proportionate decreases in regional atmospheric nitrogen deposition. Enhanced atmospheric oxidizing capacity offsets those reductions of precursor emissions. [ABSTRACT FROM AUTHOR]

The precise cause of PM2.5 (fine particular matter with a diameter smaller than 2.5 μm) explosive growth and the contribution of intermittent turbulence to the dispersion of PM2.5 are uncertain. Thus, the impact of boundary-layer structure and turbulence on the variations of surface PM2.5 during fog–haze episodes, especially during explosive growth and dispersion episodes, are investigated using turbulence data collected at a 255-m high meteorological tower in Tianjin from 2016 to 2018. Results suggest that the explosive growth of surface PM2.5 during fog–haze episodes is closely related to weak turbulent mixing, nocturnal inversions, or anomalous inversions, and the barrier effect of strong turbulent intermittency. Turbulent intermittency acts as a lid for hindering pollutant dispersion and is favourable for the fast accumulation of surface PM2.5. Apart from the potential causes mentioned above, the persistent moderate south-westerly flow is also a contributing factor for the explosive growth of surface PM2.5 during fog–haze episodes associated with regional transport. In addition, we demonstrate a possible mechanism of how intermittent turbulence affects the dispersion of PM2.5. Results verify that intermittent turbulence induced by the nocturnal low-level jet (LLJ) indeed plays an important role in the dispersion of PM2.5. However, the contribution of intermittent turbulence generated by the nocturnal LLJ to the dispersion of PM2.5 strongly relies on the intensity of the nocturnal LLJ. [ABSTRACT FROM AUTHOR]

Ammonia (NH3) can interact with other trace chemicals in the atmosphere, significantly impacting atmospheric chemistry and global climate change. China is a largely agricultural country with high consumption of nitrogen fertilizer and large livestock herds, resulting in high NH3 emissions. In this study, a comprehensive county-level inventory of Chinese NH3 emissions from 2013 to 2018 was compiled. Based on previous research, an estimate of NH3 emissions from household coal combustion was added to the inventory. The estimation of emissions from open biomass burning was improved by using a method based on fire radiative energy (FRE). The total NH3 emissions in China increased from 2013 (9.64 Tg) to 2015 (9.75 Tg), and then decreased to 9.12 Tg in 2018. Emissions from fossil fuels reached a peak value in 2018, accounting for 8.4% of total emissions, while fertilizer application and livestock waste were responsible for fewer emissions than in previous years, accounting for 27.7% and 49.9% of the total from non-fossil fuel sources, respectively. The highest emission rates were in central and southwestern China. Seasonally, NH3 emissions peaked in spring and summer. The inventory had a 1-km spatial resolution and a monthly temporal resolution, which confirmed its suitability for global and regional air quality simulations. [ABSTRACT FROM AUTHOR]

A new electro-permanent magnet combined blank holder technique has been developed by using permanent magnetic force to supply the blank holding force (BHF) for sheet metal deep drawing. In this work, the workability of the designed magnetic circuits was simulated and tested. A series of numerical simulations and experiments have also demonstrated its ability to overcome temperature rise and provide sufficient magnetic force. The advantages and availability of the combined blank holder technique were expatiated by theoretical derivation, and analyzed by FE stress analysis. The feasibility and effectiveness of the new blank holder method have been proven by a series of experiments for deep drawing a workpiece of 08Al with a diameter of 220 mm. With the segmental blank holder, the flange wrinkling is demonstrated to be suppressed well than using the single blank holder. Also, experimental results corroborated that current is only instantaneously imposed when switching magnetic force state, and not at other times. [ABSTRACT FROM AUTHOR]

Terrestrial evapotranspiration (ET) is a crucial link between Earth's water cycle and the surface energy budget. Accurate measurement and estimation remain a major challenge in geophysical, biological, and environmental studies. Pioneering work, represented by Dalton and Penman, and the development of theories and experiments on turbulent exchange in the atmospheric boundary layer (ABL), laid the foundation for mainstream methodologies in ET estimation. Since the 1990s, eddy covariance (EC) systems and satellite remote sensing have been widely applied from cold to tropical and from arid to humid regions. They cover water surfaces, wetlands, forests, croplands, grasslands, barelands, and urban areas, offering an exceptional number of reports on diverse ET processes. Surface nocturnal ET, hysteresis between ET and environmental forces, turbulence intermittency, island effects on heterogeneous surfaces, and phase transition between underlying surfaces are examples of reported new phenomena, posing theoretical and practical challenges to mainstream ET methodologies. Additionally, based on non-conventional theories, new methods have emerged, such as maximum entropy production and nonparametric approaches. Furthermore, high-frequency on-site observation and aerospace remote sensing technology in combination form multi-scale observations across plant stomata, leaves, plants, canopies, landscapes, and basins. This promotes an insightful understanding of diverse ET processes and synthesizes the common mechanisms of the processes between and across spatial and temporal scales. All the recent achievements in conception, model, and technology serve as the basis for breaking through the known difficulties in ET estimation. We expect that they will provide a rigorous, reliable scientific basis and experimental support to address theoretical arguments of global significance, such as the water-heat-carbon cycle, and solve practical needs of national importance, including agricultural irrigation and food security, precise management of water resources and eco-environmental protection, and regulation of the urban thermal environment and climate change adaptation. [ABSTRACT FROM AUTHOR]

The sensing performance of tin arsenic (SnAs) monolayer with adsorption of different gas molecules at room temperature was systematically investigated by the first-principle calculations. The interaction of all studied gas molecules with SnAs monolayer shows physisorption nature. The moderate adsorption energy (− 0.76 eV) and large charge transfer (0.21 e) results demonstrated that the SnAs monolayer is ultra-sensitive to NO2. And the sensitivity of the SnAs layer for NO2 detecting is ultra-high reach to 67,500%. Moreover, the SnAs monolayer cannot detect SO2 and NH3 gases, which could improve the reliability of the devices, comparing with other two-dimensional (2D) materials that are responsive to NO2, SO2, and NH3 gas molecules. The desorption time of the SnAs device is also short for NO2 molecules to meet the requirement of reuse. The study demonstrates the potential applications of SnAs in NO2 detecting with high selectivity and sensitivity at room temperature. [ABSTRACT FROM AUTHOR]

Background: Grain size is one of the major determinants of cereal crop yield. As a class of plant polyhydroxysteroids, brassinosteroids (BRs) play essential roles in the regulation of grain size and plant architecture in rice. In a previous research, we cloned qGL3/OsPPKL1 encoding a protein phosphatase with Kelch-like repeat domains, which negatively regulates BR signaling and grain length in rice. Results: Here, we screened qGL3-interacting proteins (GIPs) via yeast two-hybrid assay and analyzed the phenotypes of the T-DNA insertion mutants of GIPs. Among these mutants, mutant osak3 presents shorter grain length and dwarfing phenotype. OsAK3 encodes an adenylate kinase, which regulates grain size by controlling cell expansion of rice spikelet glume. Overexpression of OsAK3 resulted in longer grain length. OsAK3 interacts with qGL3 in vivo and in vitro. Lamina inclination, coleoptile elongation and root inhibition experiments showed that the osak3 mutant was less sensitive to exogenous brassinolide (BL) treatment. The transcriptional level of OsAK3 was up-regulated under BL induction. In addition, RNA-Seq data indicate that OsAK3 is involved in a variety of biological processes that regulate BR signaling and grain development in rice. Conclusions: Our study reveals a novel BR signaling component OsAK3 in the regulation of grain length, and provides novel clues for uncovering the potential functions of OsAK3 in rice growth and development. [ABSTRACT FROM AUTHOR]

Spherical gravitational wave is strictly forbidden in vacuum space in frame of general relativity by the Birkhoff theorem. We prove that spherical gravitational waves do exist in non-linear massive gravity, and find the exact solution with a special singular reference metric. Further more, we find exact gravitational wave solution with a singular string by meticulous studies of familiar equation, in which the horizon becomes non-compact. We analyze the properties of the congruence of graviton rays of these wave solution. We clarify subtle points of dispersion relation, velocity and mass of graviton in massive gravity with linear perturbations. We find that the graviton ray can be null in massive gravity by considering full back reaction of the massive gravitational waves to the metric. We demonstrate that massive gravity has deep and fundamental discrepancy from general relativity, for whatever a tiny mass of the graviton. [ABSTRACT FROM AUTHOR]

For the observer at infinity, a Schwarzschild black hole serves as an attractive opaque disk with a radius of 3 3 M that will produce the diffraction pattern of gravitational waves (GWs). In this study, we demonstrate that a bright spot, which is a diffraction effect analogous to the Poisson-Arago spot in optics, will appear when an ingoing (quasi-)plane GW is diffracted by a Schwarzschild black hole. Here, we propose the diffraction effect of the GWs described by the exact diffraction solution of the GWs using the Heun function. For the first time, the Fresnel half-wave zone method is proposed to calculate the angular part of the GW scattering stripes for the observer at infinity. The prospect of observing the diffraction bright spot is discussed with an eikonal approximation. For normal incidence (quasi)-plane waves with 100 Hz (0.1 Hz) frequency diffracted by the central black hole of the Milky Way, the time delay between the Earth bathed in a bright spot and the minimum of the first dark stripe is 3.86 (3860) d. We will witness the second bright fringe (40% amplitude of the central bright spot) after 6.2 (6200) d. This new diffraction pattern involving the early phase of inspirals and pulsars as continuous gravitational wave sources is a potential scientific target for future space-and ground-based gravitational wave detectors, respectively. [ABSTRACT FROM AUTHOR]

Characteristics of turbulence and dissipation mechanism during a polluted advection–radiation fog life cycle occurring on 26–27 November, 2018 are investigated, using the measurements at a 255-m meteorological tower located in Tianjin. The increase in relative humidity during fog formation phase is attributed to the radiative cooling and advection, indicating that the fog type is advection–radiation fog. The dispersion of PM2.5 at all heights can be attributed to the strong winds, while dispersion of PM2.5 at surface is inhibited and delayed by the thick fog. The four phases during fog life cycle are all linked to the turbulence intensity. Weak turbulence is crucial for fog formation, and the threshold σw2 range is between 0.01 and 0.10 m2 s−2. The fog dissipation at high elevations is due to strong cold and dry advection. Downdraughts at high elevations lead dry air to sink down into the lower fog layer and aid the erosion of the fog layer at medium elevations. However, the collapse of fog bank at surface is mainly due to the strong turbulence. The theory that there is a threshold relationship between turbulence and fog dissipation is verified through case analysis. However, there are two main application conditions: one is that only radiative cooling, turbulent mixing, and gravitational settling are involved in the dissipation phase of fog. The second is that the dissipation time should be at night or dawn (radiative cooling should be positive), and the fog layer collapses due to strong turbulent mixing induced by nocturnal LLJ or synoptic system. [ABSTRACT FROM AUTHOR]

Metalworking fluids used in industrial workshops may present a major threat to the health of workers who have been exposed to a high oil mist concentration over a long period of time. Therefore, monitoring the temporal and spatial distribution of particulate matter concentration has great practical significance for the control of oil mist. Traditional particle monitors are generally cumbersome, expensive, and difficult to maintain, which to some extent restricts their extensive use in workshops. Recent years have witnessed tremendous developments in the area of low-cost sensors, which are of great help in obtaining high-density pollution data. In this paper, we evaluate the performance of an inexpensive laser sensor (A4-CG) during long-term oil mist monitoring in a machine shop for the first time. With the use of Lora technology, we developed an online oil mist monitoring network to access real-time concentration, temperature, and humidity information from distributed monitors. According to the results, the sensor data correlated well with measurements by the reference instrument (R2 = 0.96), which means that the distributed sensor network can accurately detect the concentration level of oil mist in the workshop. In fact, most of the sensors demonstrated stable operation for up to half a year according to cluster analysis, while several sensors exhibited serious data drift. Furthermore, the results indicate that the peak oil mist concentration in most areas during production exceeded the value of 0.5 mg m−3 recommended by NIOSH, and it was found that appropriately lowering the relative humidity can make sampling more accurate, while lowering the temperature can reduce the oil mist concentration in the workshop. Thus, measures to control oil mist such as generation and distribution of pollution sources should be on the agenda. [ABSTRACT FROM AUTHOR]

An intensive atmospheric boundary layer (ABL) experiment was conducted simultaneously at six stations arranged in a cross shape on the North China Plain (NCP) from 26 November to 26 December 2019. The impacts of the regional ABL structure on heavy haze pollution and the relationship between the ABL height and aerosol accumulation layer (AAL) depth were discussed. Bouts of downdrafts generate a persistent descending elevated inversion layer, helping the maintenance and exacerbation of haze pollution. Continuous weak wind layers contribute to the pollutants accumulation, and low-level jets promote the removal of air pollutants. The unique landform conditions of the NCP are reflected in its regional ABL structure and further affect the spatial distribution of haze pollution. Due to the drainage flow and strong downdrafts, the western stations near the mountains have a colder surface and warmer upper air masses, resulting in a more stable stratification and worse diffusion conditions; these stations also experience a thicker weak wind layer caused by increased friction. Thus, the spatial distribution of haze is heavier in the west and lighter in the east. The convective boundary layer (CBL) height declines evidently during haze episodes, usually lower than 560 m. Furthermore, as the vertical distribution of aerosols is mainly influenced by daytime thermal turbulence and maintained at night, it is appropriate to determine the CBL height using the AAL depth. However, the AAL depth is not consistent with the stable boundary layer height due to the influence of the residual layer at night. [ABSTRACT FROM AUTHOR]

The critical collapse of a scalar field is a threshold solution of black hole formation, in which a naked singularity arises. We study here the curvature strength of this singularity using a numerical ansatz. The behavior of the Jacobi volume forms is examined along a non-spacelike geodesic in the limit of approach to the singularity. These are seen to be vanishing, thus showing that all physical objects will be crushed to zero size near the singularity. Consequently, although the critical collapse is considered to be a fine-tuning problem, the naked singularity forming is gravitationally strong. This implies that the spacetime cannot be extended beyond the singularity, thus making the singularity genuine and physically interesting. These results imply that the nature of critical collapse may need to be examined and explored further. [ABSTRACT FROM AUTHOR]

In this study, problems involving thermal field and coupled magnetic-mechanical fields of electro-permanent magnet (EPM) blank holder used in deep drawing are analyzed. Since a short current is applied to coils at the beginning of the loading or unloading of blank holding force (BHF) using this technique, the heat transfer problem in the designed magnetic cushion (EPM blank holder) is investigated. The thermal fields of double magnetic pole units (DMPUs) and magnetic cushion with 46 magnetic pole units were analyzed, respectively, by FEM, and the coil temperatures in DMPUs were measured. The results show that under normal conditions, the maximum temperature of DMPUs does not exceed 340 K after 3 h. After increasing the convective heat transfer boundary conditions, the maximum temperature can be significantly reduced. The simulated maximum temperature of the cushion increases to about 327 K after 3 h, which does not affect normal use. A coupled thermal-mechanical field of the EPM cushion was analyzed by FEM, and the results show that thermal deformation has little effect on the calculated magnetic force. Then, a coupled magnetic-mechanical field of the cushion and related components was simulated, and the distribution of blank holding pressure on the sheet was obtained. The deep drawing processes of the cylindrical cup were simulated and experimentally tested based on coupled magnetic-mechanical field analysis. The results show that the determination of air gap and magnetic level based on the analysis of coupled magnetic-mechanical field is simplified and reliable. At last, the energy consumption using the EPM blank holder technique is predicted, and it can save more than 60% energy compared with conventional blank holders. [ABSTRACT FROM AUTHOR]

Atmospheric boundary layer height (ABLH) is an important parameter used to depict characteristics of the planetary boundary layer (PBL) in the lower troposphere. The ABLH is strongly associated with the vertical distributions of heat, mass, and energy in the PBL, and it is a key quantity in numerical simulation of the PBL and plays an essential role in atmospheric environmental assessment. In this paper, various definitions and methods for deriving and estimating the ABLH are summarized, from the perspectives of turbulent motion, PBL dynamics and thermodynamics, and distributions of various substances in the PBL. Different methods for determining the ABLH by means of direct observation and remote sensing retrieval are reviewed, and comparisons of the advantages and disadvantages of these methods are presented. The paper also summarizes the ABLH parameterization schemes, discusses current problems in the estimation of ABLH, and finally points out the directions for possible future breakthroughs in the ABLH-related research and application. [ABSTRACT FROM AUTHOR]

The plasma membrane is critical in sensing, interpreting, and transducing environmental signals. In the present study, we characterized an Oryza sativa salt-responsive little protein 1 (OsSRLP1) in rice, which encodes a plasma membrane localized protein containing 54 amino acid residues. Expression of OsSRLP1 was detected in various rice tissues and was significantly induced by low temperature, drought, and salt. Overexpression of OsSRLP1 in rice improved free proline content and modulated ion balance under salt stress, which resulted in enhanced salt tolerance. Compared to wild-type rice, overexpression of OsSRLP1 inhibited seed germination under normal conditions. Interestingly, OsSRLP1 expression was up-regulated in ABL5-Like1 deficiency mutant abl1 compared to wild-type rice under salt treatment. Moreover, it was observed that overexpression of OsSRLP1 led to the dwarfism phenotype, which was correlated to the OsSRLP1 expression level in transgenic rice. In conclusion, OsSRLP1 is a little membrane protein conferring salt tolerance by modulating the ion balance and proline accumulation in rice. [ABSTRACT FROM AUTHOR]

A novel blank holder technique based on electropermanent magnet (EPM) technology is proposed, in which independent loading of blank holding force (BHF) can be realized in sheet metal forming process. The magnetic force and the resulting BHF are applied by permanent magnets rather than electromagnets, and the current is only required at the moment of loading or unloading the BHF. The BHF is convenient in control, low in energy consumption, and without overheating problem using this technique. In this paper, an experimental setup consisting of magnetic cushion, die, punch, and other components is designed based on the characteristics of EPM and requirements of deep drawing process. The magnetic cushion including blank holder and magnetic pole units is used to generate magnetic force and realize loading and unloading of BHF. Then, magnetic field analyses of a pair of magnetic pole units and the designed cushion are carried out by FEM. Also, the coupling problem involving magnetic field and stress field is further analyzed and solved by means of theoretical method and FEM, and the BHF and the blank holding pressure on the sheet using the new technique can be obtained. The deformation of the designed setup is small, and the stiffness can satisfy the requirements. The deep drawing processes of cylindrical cup of 08Al sheet with 0.98 mm thickness are simulated by using conventional blank holder and the new technique, respectively, and there are small differences of the strain distributions of the drawn parts with the two techniques. The experiments of cylindrical cup deep drawing applied four different BHFs, respectively, are carried out using EPM bank holder technique. The results indicate that the BHF applied by the designed cushion is large enough for the deep drawing process of the selected sheet. [ABSTRACT FROM AUTHOR]

Persistent severe haze pollution seldom happens in summer in Beijing. In this study, a persistent severe haze pollution event, defined as daily PM2.5 concentration higher than 150 μg m−3 on 5 consecutive days, was observed in Beijing from 26 to 30 in July 2010. It was not caused by crop residue burning during the harvest period. Weak pressure systems dominated at surface and implicated weak advection. Regional weak southerly winds with speeds of 2–3 m s−1 consistently brought pollutants from southern large-emission regions to Beijing. Surface convergence resulted from northerly winds prevailing in northern regions induced pollutants remaining in Beijing, which contributed to the maximum daily PM2.5 concentration on 26 in July. A continental high-pressure system persisted in the northwest of Beijing at 500 hPa, which led to significant sinking motion. Elevated inversion was found in the form of subsidence inversion, and this was confirmed by a skew T-logp diagram and vertical velocity analysis. It is much different from the vertical boundary layer structure in wintertime pollution period that surface-based inversion dominates. The subsidence inversion was an extremely stable layer with an average depth of hundred meters and strength of 1.4 °C. The capping effect of the inversion layer at low altitude of average 720 m limited vertical diffusion of pollutants and trapped them in a shallow layer, and thus, extremely high concentration of PM2.5 remained. WRF-Chem model simulation demonstrated that about 70% of PM2.5 was transported to Beijing from its southern regions. [ABSTRACT FROM AUTHOR]

With rapid urbanization in recent years, severe air pollution has emerged as a major issue for many regions of China, especially in some metropolises. A persistent pollution case during 6 December 2016–8 January 2017 was selected to investigate the relations between turbulent intermittency and frequent PM2.5 (particulate matters with diameter less than 2.5 μm) pollution events over the metropolitan region of Beijing, China. The accumulation of PM2.5 near the surface frequently occurred as a combined result of strong inversion layers, stagnant winds, high ambient humidity levels, and stable stratification during this case. Arbitrary-order Hilbert spectral analysis indicated that steep decreases in the PM2.5 concentration were simultaneous with the occurrence of intermittent turbulence and strong vertical mixing. A wind profiler observation revealed existence of low-level jets (LLJs) at the end of the polluted periods, suggesting that the upper-level turbulent mixing accompanied by the wind shear of LLJ was transported downward and enhanced the vertical mixing near the surface, which might have caused an abrupt reduction in PM2.5 and improvement in air conditions. [ABSTRACT FROM AUTHOR]

In this study, the characteristics of turbulence transport and intermittency and the evolutionary mechanisms were studied in different pollution stages of heavy haze weather from December 2016 to January 2017 in the Beijing area using the method developed by Ren et al. (2019) as the automatic identification of atmospheric spectral gaps and the reconstruction of atmospheric turbulence sequences. The results reveal that turbulence intermittency is the strongest in the cumulative stage (CS) of heavy haze weather, followed by in the transport stage (TS), and it is the weakest in the dissipation stage (DS). During the development and accumulation of haze pollution, buoyancy contributes negatively to turbulent kinetic energy (TKE), and horizontal wind speed is low. The classical turbulent motion is often affected by submesoscale motion. As a result, the calculation results of turbulence parameters are affected by submesoscale motion, which causes intensified turbulence intermittency. During the dissipation of pollution, the downward momentum transfer induced by low-level jets provides kinetic energy for turbulent motion in the near surface layer. The turbulent mixing effect is enhanced, and intermittency is weakened. Due to the intermittency of atmospheric turbulence, turbulence parameters calculated from the original fluctuation of meteorological elements may be overestimated. The overestimation of turbulence parameters in the CS is the strongest, followed by the TS, and the DS is the weakest. The overestimation of turbulent fluxes results in an overestimation of atmospheric dissipation capability that may cause an underestimation of pollutant concentrations in the numerical simulations of air quality. [ABSTRACT FROM AUTHOR]

Since the founding of the People's Republic of China 70 years ago, the subject of atmospheric physics and atmospheric environment has developed rapidly in China, providing important support for the development of atmospheric science and guarantee for the development of national economy. In this paper, the general advancement of atmospheric physics and atmospheric environment in last 70 years was described. The main research progress of atmospheric physics and atmospheric environment in the past 40 years of reform and opening-up was reviewed, the outstanding research achievements since the 21st century were summarized, the major problems and challenges are pointed out, and the key directions and suggestions for future development are put forward. [ABSTRACT FROM AUTHOR]

A case study is performed to investigate the behavior of turbulent intermittency in the Taklimakan Desert using an intuitive, direct, and adaptive method, the arbitrary-order Hilbert spectral analysis (arbitrary-order HSA). Decomposed modes from the vertical wind speed series confirm the dyadic filter-bank essence of the empirical mode decomposition processes. Due to the larger eddies in the CBL, higher energy modes occur during the day. The second-order Hilbert spectra L 2 (ω) delineate the spectral gap separating fine-scale turbulence from large-scale motions. Both the values of kurtosis and the Hilbert-based scaling exponent ξ q reveal that the turbulence intermittency at night is much stronger than that during the day, and the stronger intermittency is associated with more stable stratification under clear-sky conditions. This study fills the gap in the characteristics of turbulence intermittency in the Taklimakan Desert area using a relatively new method. [ABSTRACT FROM AUTHOR]

A new waste heat recovery system is presented to recover exhausted steam waste heat from the steam turbine by absorption heat pump (AHP) in a gas-steam combined cycle (GSCC) power plant. The system can decrease energy consumption and further improve the energy utilization. The performance evaluation criteria are calculated, and exergy analysis for key components are implemented in terms of the energy and exergy analysis theory. Besides, the change of these criteria is also revealed before and after modification. The net power output approximately increases by 21738 kW, and equivalent coal consumption decreases by 5.58 g/kWh. A 1.81% and 1.92% increase in the thermal and exergy efficiency is respectively obtained in the new integrated system as the heating load is 401095 kJ at 100% condition. Meanwhile, the appropriate extraction parameters for heating have been also analyzed in the two systems. The proposed scheme can not only save energy consumption but also reduce emission and gain great economic benefit, which is proven to be a huge potential for practical application. [ABSTRACT FROM AUTHOR]