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In order to explore the effect of exogenous 24-epibrassinolide (EBR, 0.1 µM) application on photosynthetic parameters in response to different light intensities and CO2 concentrations in maize seedlings under NaCl stress (180 mM), this study investigated the light response curve, CO2 response curve, and diurnal variation of photosynthesis of maize seedlings under NaCl stress. Maize cv. Jinlai 318 was used as the material, and the leaves were sprayed with 0.1 µM EBR. Net photosynthetic rate (PN), stomatal conductance (gs), intercellular CO2 concentration (Ci), and transpiration rate (E) were determined. The results showed that the light response curve, CO2 response curve, and diurnal variation trend under the four treatments (180 mM NaCl, 0.1 µM EBR, 180 mM NaCl with 0.1 µM EBR, pure water) were similar. The light saturation point of the leaves under NaCl stress was the lowest (about 1 031 mol m-2 s-1), and that in the control group (without stress) was the highest (about 1 344 mol m-2 s-1). When the light saturation point was reached (1 030 -1 350 mol m-2 s-1), the maximum PN under NaCl stress was the lowest (about 15.15 μmol m-2 s-1), while that under EBR treatment, it was the highest (about 19.86 μmol m-2 s-1). NaCl stress significantly reduced chlorophyll a, chlorophyll b, and carotenoid content and chlorophyll a/b ratio, while chlorophyll content significantly increased after EBR treatment. These results showed that exogenous EBR could effectively alleviate the damage to maize seedlings under NaCl stress, delay the light saturation phenomenon, and improve the photosynthetic capacity of maize.

Identifying Galactic PeVatrons (PeV particle accelerators) from ultrahigh-energy (UHE, >100 TeV) γ -ray sources plays a crucial role in revealing the origin of Galactic cosmic rays. The UHE source 1LHAASO J1857+0203u is suggested to be associated with HESS J1858+020, which may be attributed to the possible PeVatron candidate supernova remnant (SNR) G35.6−0.4 or H ii region G35.6−0.5. We perform detailed analysis on the very-high-energy and UHE γ -ray emissions toward this region with data from the Large High Altitude Air Shower Observatory (LHAASO). 1LHAASO J1857+0203u is detected with a significance of 11.6 σ above 100 TeV, indicating the presence of a PeVatron. It has an extent of ∼0 $\mathop{.}\limits^{\unicode{x000B0}}$ 18 with a power-law (PL) spectral index of ∼2.5 at 1–25 TeV and pointlike emission with a PL spectral index of ∼3.2 above 25 TeV. Using archival CO and H i data, we identify some molecular and atomic clouds that may be associated with the TeV γ -ray emissions. Our modeling indicates that the TeV γ -ray emissions are unlikely to arise from clouds illuminated by the protons that escaped from SNR G35.6−0.4. In the scenario in which H ii region G35.6−0.5 could accelerate particles to the UHE band, the observed GeV–TeV γ -ray emission could be well explained by a hadronic model with a PL spectral index of ∼2.0 and cutoff energy of ∼450 TeV. However, an origin in an evolved pulsar wind nebula cannot be ruled out.

Sugar content in soybean [Glycine max (L) Merr.] seed is an important quality attribute for soyfood and feed. Rapid extraction and quantification of soluble sugars in soybean seed are essential for large-scale breeding selections. In this study, using water as extractant combined with a high-performance anion exchange chromatography with pulsed amperometric detection (HPAEC-PAD) system, variability and repeatability of sugar content were tested in 20 diverse soybean genotypes. Individual sugars were clearly resolved and identified, including sucrose, stachyose, raffinose, glucose, fructose, and verbascose. Analysis of variance (ANOVA) revealed a highly reproducible estimation of sucrose, stachyose, and raffinose. PI 243545 was confirmed as a unique germplasm with the highest sucrose (105.48 mg/g) and total sugar (148.76 mg/g) content. Two low-oligosaccharide accessions, PI 200508 and 03CB-14, were confirmed with extremely low concentrations of raffinose and stachyose. PI 417559 was identified as a high glucose and fructose germplasm. The identified germplasm with unique sugar profiles will be valuable in breeding specialty soybeans for improved sugar content. The sugar testing method will facilitate the screening of seed sugar profiles in a large-scale soybean breeding program.

Abstract In this paper, an initial pressure adjustable explosion vessel was developed, and the effect of negative pressure, positive pressure (0.2–1.8 atm) different initial ambient pressure on the explosive shock wave generated by the explosion of explosives was studied. The relationships between the specific impulse, shock wave velocity, the amount of explosive gas products and the ambient pressure were analyzed for different initial pressure environments. It was found that: the overpressure of the blast shock wave decreases with the initial ambient pressure of the explosion, and there exists a negative pressure environment with a dramatic pressure decrease near 0.6 atm, defined as the super-sensitive negative pressure Pcr. The propagation velocity of an explosive wave increases with a decrease in the ambient pressure, and the propagation velocity at a pressure of 1.8 atm is four times less than the velocity at a pressure of 0.2 atm. The production of explosive gas products did not change. The greater the initial pressure of the environment where the explosive is located, the smaller the ratio of the gas generated by the explosion to the initial force gas in the explosion vessel is, and the greater the impact on the propagation of shock waves is. The maximum attenuation of the first specific impulse i 1 is 72.97% and the maximum attenuation of the second specific impulse i 2 is 72.39%. The experiments provide reference data for high-altitude military confrontation, high-altitude weapons and ammunition development, and deep-earth protection engineering.

Misalignment effects increase the risk of scratch or seizure failure for the journal bearings-rotor system. To investigate the performances of misaligned journal bearings, a full-scale journal bearings-rotor system test rig is designed and journal orbits are tested under different speeds. Then, a THD lubrication model is established to simulate lubrication performances under different misalignment conditions. The results show that for a misaligned journal bearings-rotor system, the center of the orbits of the bearing closing to coupling is fixed around the coupling. The orbits center of the bearing far away coupling is floating gradually with an increasing speed. The vibration amplitude of bearing closing to coupling is larger than that of bearing far away from the coupling. When the minimum oil film thickness is decreasing, the maximum film temperature is increasing except for the bearing closing to coupling. For different misalignment directions, maximum film temperature is determined by the position of the high pressure zone and high temperature zone.

Passive films on metal surfaces provide better corrosion resistance, but they can degrade in long-term service. Here the authors demonstrate a strategy to engineer crystallographic configuration at the metal/film interface to further improve corrosion resistance.

Abstract The focal plane camera is the core component of the Wide Field-of-view Cherenkov/fluorescence Telescope Array (WFCTA) of the Large High-Altitude Air Shower Observatory (LHAASO). Because of the capability of working under moonlight without aging, silicon photomultipliers (SiPM) have been proven to be not only an alternative but also an improvement to conventional photomultiplier tubes (PMT) in this application. Eighteen SiPM-based cameras with square light funnels have been built for WFCTA. The telescopes have collected more than 100 million cosmic ray events and preliminary results indicate that these cameras are capable of working under moonlight. The characteristics of the light funnels and SiPMs pose challenges (e.g. dynamic range, dark count rate, assembly techniques). In this paper, we present the design features, manufacturing techniques and performances of these cameras. Finally, the test facilities, the test methods and results of SiPMs in the cameras are reported here.

The transient hydrodynamic lubrication model of tilting pad journal bearings (TPJBs) was established by the computational fluid dynamics (CFD) method and the self-developed dynamic grid program. The fluid-structure interaction between the flow field and the rotor motion, the pads rotations was realized. The feasibility of the model is proved by comparing with the experimental data. The dynamic response of TPJBs under the various unbalance, the loading modes and the rotating speeds was studied. The dynamic response of TPJBs is further analyzed through a research of the relationships among the shaft whirl orbits, transient force acting on the shaft, rotation angles of the pads and transient oil film force of the pads. With the increase of unbalance, the whirl orbits expand and whirl orbits centers rise continuously. The whirl orbits and orbit center attitude angles of TPJBs are smaller than those of fixed-pad journal bearings. Compare with the load between pads, the whirl orbits are smaller and whirl orbits centers drop slightly under the load on pads. With the increase of rotating speed, the whirl orbits expand nonlinearly, whirl orbit center rises nonlinearly. The transient force acting on the shaft, the rotation angles of the pads and the transient oil film force of the pads change periodically, and the period and frequency of these changes are the same as that of the shaft rotation. The maximum force acting on the shaft appear before the maximum shaft center position (the vertexes of the whirl orbit).

Abstract Background In China, ethnic minorities often live in frontier areas and have a relatively small population size, and tremendous social transitions have enlarged the gap between eastern and western China, with western China being home to 44 ethnic minority groups. These three disadvantages have health impacts. Examining ethnicity and health inequality in the context of western China is therefore essential. Methods This paper is based on data from the 2010 China Survey of Social Change (CSSC2010), which was conducted in 12 provinces, autonomous regions and province-level municipalities in western China and had a sample size of 10,819. We examined self-rated health and disparities in self-rated health between ethnic minorities and Han Chinese in the context of western China. Self-rated health was coded as poor or good, and ethnicity was coded as ethnic minority or Han Chinese. Ethnic differences in self-rated health was examined by using binary logistic regression. Associations among sociodemographic variables, SES variable, health behaviour variable, health problem variables and self-rated health were also explored. Results Fourteen percent of respondents reported their health to be poor. A total of 15.75% of ethnic minorities and 13.43% of Han Chinese respondents reported their health to be poor, indicating a difference in self-rated health between ethnic minorities and Han Chinese. Age, gender, marital status, education, alcohol, and health problems were the main factors that affected differences in self-rated health. Conclusion In western China, there were obvious ethnic disparities in self-rated health. Elderly ethnic minorities, non-partnered ethnic minorities, ethnic minorities with an educational level lower than middle school, and ethnic minorities with chronic disease had higher odds of poor self-rated health.

Collecting experimental evidence of chloride ion attack on protective passive metallic films due to corrosion remains challenging. Here, the authors show that the boundaries between nanocrystals and amorphous regions in the passive film ease chloride transport even as they do not coincide with areas of high chloride concentration.

Time-series InSAR technology has become a popular land subsidence monitoring method in recent years, because of its advantages such as high accuracy, wide area, low expenditure, intensive monitoring points and free from accessibility restrictions. In this paper, we applied two kinds of satellite data, ALOS PALSAR and RADARSAT-2, to get the subsidence monitoring results of the study area in two time periods by time-series InSAR technology. By analyzing the deformation range, rate and amount, the time-series analysis of land subsidence in mining area was realized. The results show that InSAR technology could be used to monitor land subsidence in large area and meet the demand of subsidence monitoring in mining area.

Abstract Engineering of novel functional nanocomposite as like as the metallic nanocrystals supported non-stoichiometric perovskite nanomaterial in controlled parameters (size, shape and ratio of chemical characteristics) is a challengeable task. In this context, we present a facile route to fabricate and study its physicochemical property at real time mode in this report. Nanoscale pure Pb crystals surfaced on non-stoichiometric A-site deficient Pb1-xTiO3-y nanoparticle were fabricated when a precursor lead titanate (PbTiO3) nanoparticle was exposed to an electron beam irradiation (EBI) in a transmission electron microscope (TEM) at ambient temperature. In the state of the art, the chemical states and electronic structure of non-irradiated and irradiated PbTiO3 were studied by X-ray photoelectron spectroscopy (XPS). Electron bombardment resulted in a new visible feature at low binding energy in the Pb 4f core level, while Ti 2p and O 1s line shape showed slight changes. The Fermi level of the corresponding materials was determined to be 1.65 ± 0.1 eV and 2.05 ± 0.1 eV above the valence band maximum, respectively. The normal, weakly p-type PTO exhibits peculiar n-type feature after EBI process (The Fermi level moves near to the conduction band). A feasible mechanism is proposed involving the electron-stimulated local bond-breaking phenomenon in PbTiO3.

Inherent elastic strains are useful to tune the physical properties of functional materials but it is difficult to build. Here, Tanget al. report a fabrication of inhomogeneous strains with a linear gradient as giant as 106 per meter in a BiFeO3 nanostructure array grown on a LaAlO3substrate.

Besides the negative longitudinal magnetoresistance (MR), planar Hall effect (PHE) is a newly emerging experimental tool to test the chiral anomaly or nontrivial Berry curvature in Weyl semimetals (WSMs). However, the origins of PHE in various systems are not fully distinguished and understood. Here we perform a systematic study on the PHE and anisotropic MR (AMR) of Td-MoTe2, a type-II WSM. Although the PHE and AMR curves can be well fitted by the theoretical formulas, we demonstrate that the anisotropic resistivity arises from the orbital MR (OMR), instead of the negative MR as expected in the chiral anomaly effect. In contrast, the positive MR indicates that the large OMR dominates over the chiral anomaly effect. This explains why it is difficult to measure negative MR in type-II WSMs. We argue that the measured PHE can be related with the chiral anomaly only when the negative MR is simultaneously observed.

The electronic structures of a representative rare earth monopnictide (i.e., DySb) under high magnetic field (i.e., in the ferromagnetic state) are studied from both experimental and theoretical aspects. A non-saturated extremely large positive magnetoresistance (XMR) is observed (as large as 3.7 × 104% at 1.8 K and 38.7 T), along with the Shubnikov-de Haas oscillations that are well reproduced by our first principles calculations. Three possible origins of XMR are examined. Although a band inversion is found theoretically, suggesting that DySb might be topologically nontrivial, it is deeply underneath the Fermi level, which rules out a topological nature of the XMR. The total densities of electron-like and hole-like carriers are not fully compensated, showing that compensation is unlikely to account for the XMR. The XMR is eventually understood in terms of high mobility that is associated with the steep linear bands. This discovery is important to the intensive studies on the XMR of rare earth monopnictides.

The measurement of soil total nitrogen (TN) by hyperspectral remote sensing provides an important tool for soil restoration programs in areas with subsided land caused by the extraction of natural resources. This study used the local correlation maximization-complementary superiority method (LCMCS) to establish TN prediction models by considering the relationship between spectral reflectance and TN based on spectral reflectance curves of soil samples collected from subsided land determined by synthetic aperture radar interferometry (InSAR) technology. Based on the 1655 selected effective bands of the optimal spectrum (OSP) of the first derivate differential of reciprocal logarithm ([log{1/R}]'), (correlation coefficients, P < 0.01), the optimal model of LCMCS method was obtained to determine the final model, which produced lower prediction errors (root mean square error of validation [RMSEV] = 0.89, mean relative error of validation [MREV] = 5.93%) when compared with models built by the local correlation maximization (LCM), complementary superiority (CS) and partial least squares regression (PLS) methods. The predictive effect of LCMCS model was optional in Cangzhou, Renqiu and Fengfeng District. Results indicate that the LCMCS method has great potential to monitor TN in subsided land caused by the extraction of natural resources including groundwater, oil and coal.

In this paper, we use the Hydrologic Modeling System (HEC-HMS) to simulate two flood events to investigate the effect of watershed subdivision in terms of performance, the calibrated parameter values, the description of hydrologic processes, and the subsequent interpretation of water balance components. We use Stage IV hourly NEXRAD precipitation as the meteorological input for ten model configurations with variable sub-basin sizes. Model parameters are automatically optimized to fit the observed data. The strategy is implemented in Clear Creek Watershed (CCW), which is located in the upper Mississippi River basin. Results show that most of the calibrated parameter values are sensitive to the basin partition scheme and that the relative relevance of physical processes, described by the model, change depending on watershed subdivision. In particular, our results show that parameters derived from different model implementations attribute losses in the system to completely different physical phenomena without a notable effect on the model's performance. Our work adds to the body of evidence demonstrating that automatically calibrated parameters in hydrological models can lead to an incorrect prescription of the internal dynamics of runoff production and transport. Furthermore, it demonstrates that model implementation adds a new dimension to the problem of non-uniqueness in hydrological models.

Understanding the law of mining surface dynamic subsidence plays an important role in protecting the villages and other infrastructures against subsidence damage and disturbance. Unfortunately, the existed methods are mostly based on a few sparse leveling measurements, the accuracy and reliability of which are degraded when the feature points of the leveling measurements are lost in the processing of subsidence evolution. This paper presents a method to analysing the law of mining surface dynamic subsidence by fusing interferometric synthetic aperture radar (InSAR) and leveling measurements. By comparing the fitted results obtained by fusing InSAR/leveling and those only by independent leveling, it is shown that the InSAR/levelling fusion not only can make up the deficiency when the leveling measurements lost the feature points of dynamic subsidence, but also can improve the accuracy and reliability of results.

Aluminum films were grown on SrTiO3 (100) substrates using a plasma-assisted molecular beam epitaxy system. We found that the intensity of defect emission coming through the Al films was enhanced to two fold. Although the surface plasmon energy is far from the defect emission, off-resonance enhancement is still possible from Al/SrTiO3. Moreover, the samples with Al films exhibits ferromagnetism, with wasp-waist hysteresis loops and exchange bias effects. The ferromagnetism may be attributed to the charge transfer between Al and the SrTiO3 matrix. This work is valuable in developing SrTiO3 which is a promising material used in optical and magnetic related application.