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MgH2, TiH2, and ZrH2 are three typical metal hydrides that have been gradually applied to composite explosives and propellants as additives in recent years. To evaluate ignition sensitivity and explosion severity, the Hartmann device and spherical pressure vessel were used to test ignition energy and explosion pressure, respectively. The results showed that the ignition sensitivity of ZrH2, TiH2 and MgH2 gradually increased. When the concentration of MgH2 is 83.0 g/m3 in Hartmann device, the ignition energy attained a minimum of 10.0 mJ. The explosion pressure of MgH2 were 1.44 times and 1.76 times that of TiH2 and ZrH2, respectively, and the explosion pressure rising rate were 3.97 times and 9.96 times that of TiH2 and ZrH2, respectively, through the spherical pressure vessel. It indicated that the reaction reactivity and reaction rate of MgH2 were higher than that of TiH2 and ZrH2. In addition, to conduct in–depth theoretical analysis of ignition sensitivity and explosion severity, gas production and combustion heat per unit mass of ZrH2, TiH2 and MgH2 were tested by mercury manometer and oxygen bomb calorimetry. The experimental results revealed that MgH2 had a relatively high gas production per unit mass (5.15 mL/g), while TiH2 and ZrH2 both had a gas production of less than 2.0 mL/g. Their thermal stability gradually increased, leading to a gradual increase in ignition energy. Furthermore, compared with theoretical combustion heat, the combustion ratio of MgH2, TiH2 and ZrH2 was more than 96.0 %, with combustion heat value of 29.96, 20.94 and 12.22 MJ/kg, respectively, which was consistent with the explosion pressure and explosion severity test results.

The Paleo-Tethys Ocean records the initial geodynamic processes related to the dispersion of Gondwana and the subsequent accretion of Laurasia. However, whether the blueschist-bearing central Qiangtang metamorphic belt (CQMB) within the Qiangtang Block represents an in situ Paleo-Tethys suture remains controversial. Since the starting point of this debate is the subduction type (i.e., warm subduction vs. cold subduction) recorded by the associated central Qiangtang blueschists, here, we approach this debate by investigating their petrogenesis, which records the subduction and exhumation of an oceanic plate. We reconstruct the clockwise pressure–temperature (P–T) paths using phase equilibrium modeling for two types of blueschists from the Rongma and Gangma Co areas, and their peak P–T conditions reveal typical cold subduction with a uniform low geothermal gradient of 5–10 °C/km. Combining this information with published radiometric dating and bulk-rock geochemical data, we find that the central Qiangtang blueschists record almost all of the early Permian-Late Triassic subduction of the LSPTO and subsequent continental subduction, as well as the Late Triassic exhumation of oceanic and continental material. This study confirms that the central Qiangtang blueschist-bearing melange marks an in situ suture, which formed during the northward subduction and subsequent exhumation of the LSPTO.

The performance of image super-resolution (SR) have been greatly improved with deep convolution neural network (CNN). Despite image SR targets at recovering high-frequency details, most SR methods still focus on generating high-level features via a deep and wide network. They lack the discriminative ability of high-frequency information hidden in the abundant CNN features, thus hindering CNNs to yield better SR results. To tackle this issue, we propose two new attention mechanism: context weighted channel attention (CWCA) and persistent spatial attention (PSA). They modulate abundant features by suppressing the useless features and enhancing the interested ones in a channel-and-spatial manner. The network is then enabled to concentrate more on informative features closely related to the high-frequency components of an image. Furthermore, we propose enhanced attention residual groups with dense connection (EARG-D) to capture not only short-term information but also long-term information to maintain more useful features. Finally, we construct a deep enhanced context attention super resolution network (EASR) for better image reconstruction. Quantitative and qualitative experiments well demonstrate that our proposed method performs better than existing state-of-the-art SR methods.

The seven-wire strands are the crucial components of prestressed structures, though their performance inevitably degrades with the passage of time. The ultrasonic guided wave methods have been intensely studied, owing to its tremendous potential for full-scale applications, among the existing nondestructive testing methods, for evaluating the stress status of strands. We have employed the theoretical and finite element methods to solve the dispersion curve of single wire and steel strands under various boundary conditions. Thereafter, the singular value decomposition was adopted to work with the simulated and experimental signals for extracting a feature vector that carries valuable stress status information. The effectiveness of the vector was verified by analyzing the relationship between the vector and the stress level. The vector was also used as an input to establish a support vector regression model. The accuracy of the model has been discussed for different sample sizes. The results show that the fundamental mode dispersion curve offset on the high-frequency part and cut-off frequency increases as the boundary constraints enhance. Simulated and experimental results have demonstrated the effectiveness and potential of the proposed support vector regression method for evaluating the stress level in the strands. This method performs well even at low stress levels and the reliability can be enhanced by adding more samples.

Omosita colon (Linnaeus, 1758) (Coleoptera: Nitidulidae) is an economically important storage pest worldwide and a forensically important beetle. The first complete mitochondrial genome (mitogenome) of O. colon was sequenced in this study using the next-generation sequencing. The mitogenome of O. colon is circular with a total length of 16,544 bp, which consists of 13 protein-coding genes, 22 transfer RNA genes, two ribosomal RNA genes, and a non-coding control region. The order and orientation of genes were identical with that of the ancestral insects. This study provides genomic data for mitogenome library of the genus Omosita to investigate evolutionary and systematic studies. It also provides a molecular basis to infer the postmortem interval (PMImin) with O. colon.

More and more attention has been paid to the supporting problem of deep soft rock roadway floor with long-term water immersion in recent years. However, the existing soft rock roadway support technology rarely takes into account the influence of the immersion softening phenomenon of the roadway floor and the self-supporting structure characteristics of the surrounding rock on the stability of the surrounding rock at the same time, and the influence of the creep characteristics of rock on the deformation zone of the surrounding rock requires further research on the nature and division of the self-supporting structure of the surrounding rock. In response to the issues mentioned, based on the loading and unloading properties of the surrounding rock of the soft rock roadway, a new concept of the internal and external self-bearing structure was proposed. The fact of water-immersed mudstone softening in the soft rock roadway floor was revealed through the field practice, and the shape of the internal and external bearing structure was determined based on the in situ monitoring results. Then, the instability mechanism of the internal and external self-bearing structure of the surrounding rock was analyzed, the position of the critical control point was calculated, and the key control technology based on the method of controlling floor heave by using double-row anchor cables to control the deformation of the roadway sides was put forward. Finally, the field industrial test showed that this support technology can effectively control the deformation and failure of soft rock roadway in the case of water immersion on the floor. This work can provide a technical reference for similar roadway support designs.

A simple FBG Fabry-Perot sensor system with high sensitivity based on fiber laser beat frequency and Vernier effect is proposed and demonstrated. The sensor head is a Fabry-Perot (F-P) resonant cavity formed by two identical fiber Bragg gratings (FBGs), and the F-P cavity is a part of the laser cavity as a mirror. Vernier effect can be realized by choosing appropriate F-P cavity length and laser cavity length. So we achieved the sensitivity multiplication of the sensor, with sensitivity of 299.17 kHz/°C. The sensing information can be obtained by tracking the envelope of beat frequency signals generated by Vernier effect. This sensor system has the advantages of low cost, simple structure and high sensitivity.

The application of waste alkali liquids as a substitute of sodium hydroxide for the saponification to improve the collection performance of fatty acids was investigated by saponification reaction test and flotation test. The results of the saponification reaction test indicated that the optimal conditions for the saponification were stirring rate of 55 r/min, initial temperature of 40 °C and stirring time of 45 min. Meanwhile, the laboratory scale and industrial scale flotation experiments showed that the fatty acid salt synthesized by wastewater achieved an index comparable to fatty acid sodium synthesized by sodium hydroxide. As a consequence, it was feasible to replace sodium hydroxide with the wastewater from zeolite production for fatty acid saponification. The cross-border utilization of waste alkali liquids not only reduced environmental pollution, but also produced excellent economic benefits.

To improve the safety of lithium-ion batteries (LIBs), a polyether amide–silica (PEI-SiO2) composite membrane was developed by the in situ hydrolysis of tetraethylorthosilicate (TEOS) and its subsequent self-assembly on the surface of PEI fibers. Because of the presence of the SiO2 shell, the PEI-SiO2 composite membrane exhibited good thermal stability at high temperatures. The composite membrane did not change its color and size after heating at 200°C for 1 h as well as exhibited excellent flame retardancy. Moreover, the membrane maintained its high porosity even after the introduction of shell layers. The electrolyte is completely absorbed in the membrane within 0.5 s. The electrolyte uptake was up to 625%, and the ionic conductivity was up to 1.9 mS/cm at room temperature. Compared to the polyolefin membrane and the pure PEI membrane, the PEI-SiO2 composite membrane showed higher electrochemical stability, with an electrochemical window of up to 5.5 V. The battery assembled with the composite membrane showed excellent cycle stability, and the capacity retention rate was as high as 98.6% after 50 cycles. The LIBs based on the PEI-SiO2 composite membrane exhibited safe operation and high electrochemical performance, thus highlighting the applicability of the composite membrane in high-power batteries.

The utilisation of nickel slag and waste glass powder as raw materials for preparing foamed ceramic was studied. The influences of the mixture design and foaming-agent dosage on the properties and microstructures of foamed ceramic were investigated in terms of the density, flexural strength, phase composition and micromorphology. Results showed that incorporating nickel slag improved the flexural strength and uniformity of the pore structure. However, owing to the high density of nickel slag, its excessive usage may impact the development of foamed ceramic density and porosity as a side effect. The Na2CO3 dosage was another crucial factor determining foamed ceramic properties. A nickel slag content of was 20% and a Na2CO3 content of 7% decreased the foamed ceramic density to 0.498 g/cm3, with a corresponding flexural strength of 2.66 MPa and a higher porosity of 80.06%.

The hot compression deformation behavior of Cu–3Ti–0.1Zr alloy with the ultra-high strength and good electrical conductivity was investigated on a Gleeble–3500 thermal-mechanical simulator at temperatures from 700 to 850 °C with the strain rates between 0.001 and 1 s−1. The results show that work hardening, dynamic recovery and dynamic recrystallization occur in the alloy during hot deformation. The hot compression constitutive equation at a true strain of 0.8 is constructed and the apparent activation energy of hot compression deformation Q is about 319.56 kJ/mol. The theoretic flow stress calculated by the constructed constitutive equation is consistent with the experimental result, and the hot processing maps are established based on the dynamic material model. The optimal hot deformation temperature range is between 775 and 850 °C and the strain rate range is between 0.001 and 0.01 s−1.

Cu-5.8vol.-%TiB2 composites reinforced with different sized TiB2 particles were prepared by spark plasma sintering (SPS). The arc erosion resistance was examined using a JF04C electrical contact in...

The electrochemical determination of copper (II), lead (II) and mercury (II) ions has been studied and analyzed in this paper. Preparation of polyaniline functional ink by electronic ink technology was proposed. Screen-printed carbon electrode (SPCE) modified by ethylene diamine tetraacetic acid @ polyaniline/multi-walled carbon nanotube nanocomposite structure was used as an electrochemical sensor by all-printed technology to selectively detect copper, lead and mercury ions. The improved electrode is a great improvement in process simplicity and practicability. Square-wave voltammetry was used to detect the concentration of copper, lead and mercury ions, and the selectivity, sensitivity, reproducibility and stability of the ions were also studied. The detection results show that the modified SPCE electrode has high selectivity, sensitivity and reproducibility. The detection limit of copper ions was determined as 55.4 pM, that of lead ions was 22 pM, and that of mercury ions was 17.8 pM.

Photostable and bright organic dyes emitting in the near-infrared region are highly desirable for long-term dynamic bioimaging. Herein, we report a synthetic approach to build novel methoxy modified Si-rhodamine (SiRMO) dyes by introducing the methoxybenzene on the xanthene moiety. The brightness of SiRMO increased from 2300 M-1 cm-1 (SiRMO-0) to 49000 M-1 cm-1 (SiRMO-2) when the substituent 2,5-dimethoxybenzene was replaced with 2,6-dimethoxybenzene. Moreover, the stability of SiRMO-2 was significantly improved due to the steric hindrance protection of the two methoxy groups on the ninth carbon atom of the xanthene. After fast cellular uptake, the SiRMO dyes selectively stained the mitochondria with a low background in live cultured cells and primary neurons. The high brightness and stability of SiRMO-2 significantly improved the capability of monitoring mitochondria dynamic processes in living cells under super-resolution conditions. Moreover, with the fluorescence nanoscopy techniques, we observed the structure of mitochondrial cristae and mitochondria fission, fusion, and apoptosis with a high temporal resolution. Under two-photon illumination, SiRMO-2 showed also enhanced two-photon brightness and stability, which are important for imaging in thick tissue.

When a transformer is running, the insulation oil gradually becomes degraded due to various factors such as electricity and heat, during which low molecular weight gases are formed upon decomposition. By analyzing the gas content in the oil, the state of the insulation oil can be identified, thereby providing an effective basis for transformer fault analysis and diagnosis. However, when the types and severity of the internal faults inside the transformer are different, the components and contents of the gases dissolved in the oil also differ. Sometimes when the types of faults are the same, the gas content may be different. Therefore, if the characteristic of the specific gas content corresponding to a type of fault can be obtained, the transformer faults can be accurately identified according to the contents of different gases, which can most efficiently ensure the reliable operation and maintenance of power transformers. In this paper, an identification method based on the deep transfer network was proposed. According to this method, by studying the existing gas contents and states based on a large number of training data to discover their characteristics, the states of gases in the oil can be precisely identified. Experiments have proved the effectiveness of this method. The ability of state identification by this method is far superior to that of the other existing methods.

Urea is an important molecule in physiology and industry. The detection of urea by electrochemical sensors has broad application prospects in food detection and kidney disease screening. This paper introduces the preparation method of MWCNT/PANi electronic ink and its composite electrode, which was applied to the detection of urea. The linear range of the MWCNT/PANi composite electrode was increased by adjusting the concentration of MWCNT. The maximum linear range was 10 to 100 μM when 5.6 mg MWCNT was added. The sensitivity of the electrode was 2.435 $$\times$$ 10−4 mA mM−1 cm−2 and the detection limit was 53.9 nM. At the same time, an algorithm was proposed to identify and analyze the data collected by the electrochemical workstation in view of the errors existing in the calculation of the electrochemical sensor when analyzing the optimal response voltage of the electrode. This method was used to set constraints and screen the optimal working voltage. Experimental results show that this method has certain advantages.

The exploitation of high-efficiency and cheap bifunctional cathode electrocatalyst is of significant importance to rechargeable zinc-air batteries. In this paper, a bimetallic sulfide coupled with a CNT ((Co, Mg)S2@CNTs) hybrid catalyst is developed via a proposed vulcanization process. The (Co, Mg)S2@CNTs) with controllable Mg substitution has a tailored crystal structure (amorphous and crystalline), which catalyzes the oxygen reduction/evolution reaction (ORR/OER). The active sites of CoS2@CNTs are activated by doping Mg ions, which accelerates the kinetics of the oxygen adsorption for ORR and oxygen desorption for OER. Meanwhile, the hybrid catalyst exhibits a unique hierarchal morphology and a "catalytic buffer", which further accelerate the mass transfer of catalytic processes. In addition, the outer wall of CNTs as substrate effectively avoid the agglomeration of (Co, Mg)S2 particles by reasonably providing adsorption sites. The inner and outer walls of CNTs form a high-speed conduction pathway, quickly transferring the electrons produced by oxygen catalytic reactions. As a result, the (Co, Mg)S2@CNTs exhibit an ORR performance comparable with commercial catalyst Pt/C-RuO2 and remarkable OER performance (Ej=10 = 1.59 V). The high power density of 268 mW cm-2 and long-term charge/discharge stability of the zinc-air battery proves the feasibility of (Co, Mg)S2@CNTs application in high-power devices.

To develop a high-accuracy method for predicting SCB based on the analysis of the shortcomings of the wavelet neural network (WNN) model, an improved WNN model to predict SCB is proposed herein. Th...

This work evaluated the anionic polysaccharides to improve the functional properties and antioxidant activities, and compared the effects on covalently-linked the soy protein isolate (SPI)- (–)-epigallocatechin-3-gallat (EGCG) binary complexes. The increasing molecular weight via covalent insertion of (–)-epigallocatechin-3-gallat (EGCG) into the soy protein isolate (SPI) was verified by SDS-PAGE. The addition of polysaccharides had no obvious effects on the molecular weight, indicating noncovalent insertion by adsorption. Fourier transform infrared spectroscopy (FT-IR) analysis suggested that SPI-EGCG complexes mixed with polysaccharides changed the secondary structures of SPI with a decrease in α-helix and an increase in β-turn. The emulsions exhibited better stability index (ESI) by adding polysaccharides than the binary complexes emulsion, with decreased particle sizes and increased absolute ζ-potential values, while the value of ESI for the pectin mixed increased more. The 1,1-diphenyl-2-picrylhydrazyl radical (DPPH•) scavenging capacity of SPI-EGCG complexes with the addition of polysaccharides were both greater than 70 %. These findings indicated that anionic polysaccharides could be potentially used as a natural and safe alternative for regulating covalently-linked SPI-EGCG emulsion stability and improving emulsion oxidation resistance.

In this paper, a novel local surface nanocrystallization treatment is introduced to design the anti-buckling rectangular plate. The mechanical properties and critical buckling loads of the plates are greatly improved by the surface nanocrystallization technology. Several local nanocrystallization layouts, including the horizonal stripes distribution, the vertical stripes distribution and the spaced latticed blocks distribution, are designed and numerical simulations are carried out to evaluate the stability of the plates. Results show that the critical buckling load was significantly improved by the local nanocrystallization treatment. Among all the designs, the critical buckling loads for the vertical nanocrystallization layouts is the optimal one. And the technology can also be extended to the anti-buckling design of other structures.

International audience; The Yuleken porphyry Cu-Mo deposit located in the Chinese Altay-East Junggar, a section of the Central Asian Orogenic Belt, the world's largest Phanerozoic subduction-accretionary orogen, witnessed the multistage tectonic-magmatic evolution and mineralization from arc to syn- and post-collision environment over a time span of about 52 Ma. Four types of molybdenite have been distinguished: (1) primary magmatic-hydrothermal, undeformed molybdenite in porphyry, (2) recrystallized molybdenite associated with ductile deformation, (3) recrystallized, intrafoliational molybdenite, and (4) fracture-related hydrothermal molybdenite, and these are characterized by decreasing Re abundances from magmatic to hydrothermal conditions. Individual molybdenite types are non-stoichiometric and exhibit the following negative correlation between the Mo and Re contents:Re (apfu) = −0.0026 Mo (apfu) + 0.00268.This trend reflects successive stages of tectonic-hydrothermal events from a magmatic island-arc to a post-collisional setting. These repetitive mineralization events produced Mo enrichment and higher overall Mo grade of the Yuleken deposit, and are recorded in progressively decreasing Re concentrations in molybdenite. Statistical evaluation of Mo and Re abundances in giant to small porphyry deposits worldwide also indicates that decreasing Re in molybdenite will lead to lower overall Re resource (in a single deposit) and to greater overall Mo resource (in the same deposit). Multiple mineralization processes related to repetitive tectonomagmatic episodes in large porphyry Mo deposits that display Re depletion in molybdenite suggest that reworking of mantle-derived porphyry systems by successive events of crustal growth may be the responsible for Mo enrichment and higher overall Mo ore grade, and eventually produce giant porphyry molybdenum deposits.

The 5th sub-member in 5 Member Ordovician Majiagou Formation in Daniudi Gas Field, Ordos Basin, is deposited in an environment consisting of an ancient epicontinental sea, where very fine crystalline dolostone reservoir has developed. In this study, based on the petrological and geochemical characteristics, the genesis of the dolomite developed in M55 were studied by analyzing the properties and sources of the dolomitization fluids, and the influence of the paleogeomorphology differences on the distribution of dolostone was also discussed in order to clarify the distribution of the dolostone developed in the lime flat of the epicontinental sea. The dolostone of the M55 had a crystal structure, mainly including microcrystalline and very fine crystalline. The content of MgO and CaO in dolomite was negatively correlated, indicating that it was the result of replacement. The dolomite was dark red under cathode luminescence, and the distribution mode of rare earth elements showed the negative anomaly of Ce and Eu, indicating that the dolomitization fluid was sea-sourced fluid. The δ13C, δ18O, and 87Sr/86Sr isotope range of limestone was similar to that of Ordovician seawater in the study area, whereas the δ13C, δ18O, and 87Sr/86Sr of dolostone were obviously more positive than that of limestone. The substitute index of the salinity (Z) of the dolomitization fluid was higher than 122, which is higher than limestone (Z = 120.5), indicating that the dolomitization fluid was slightly evaporated seawater. The wormholes observed on the core and the gypsum in the penecontemporaneous period observed in the thin sections indicated that the dolostone was formed in a period when the sea level was relatively low, and it was the result of seepage–reflux dolomitization. By analyzing the correlation between the thickness of dolostone and the paleogeomorphology of the M55 of the sedimentary period, it was found that the thickness of dolostone at relatively high altitude was significantly larger than that of other areas. The development of dolostone was controlled by sea level, and the local paleogeomorphology controls the distribution of dolostone during the period of low sea level. There were many more limestone–dolostone cycles and larger cumulative thicknesses of dolostone at relatively higher topography. This study provides a theoretical basis for the prediction of the distribution of dolostone reservoirs in the carbonate tidal flat environment dominated by lime flats under the background of the ancient epicontinental sea.

Akashiwo sanguinea is closely linked to the healthy growth of Labrenzia sp. PO1. Herein, PO1 and SY1 strains of Labrenzia sp. were isolated from A. sanguinea to investigate their growth. A total of 6067 genes in the Labrenzia sp SY1 and 6067 genes in Labrenzia sp PO1 were identified by RNA sequencing. Totally, 2402 genes out of 6067 were found as differentially expressed genes (DEGs). PO1 strain, 595 with decreased transcript abundance, and 1807 increase transcript abundance. Total 2320 DEGs, 766 with decreased transcript abundance, and 1554 increase transcript abundance were found in the SY1 strain. Transcriptome analysis divulged that DEGs were enriched with regulating metabolic processes, biological processes, and binding activities and may play critical roles in Labrenzia sp. PO1 growth. The ABC transporter pathway was also enriched in PO1 with 23 genes encoding ABC transporters with increased transcript abundance only in this strain. ABC transporter transcript levels and Labrenzia sp. PO1 growth was highest at 32 h, indicating that transporter-encoding genes may be involved in PO1 growth through nutrient transport. Moreover, their low expression in SY1 may be related to its slower growth. This study of Labrenzia sp. PO1 and SY1 transcriptomes may be used as a foundation for future research on the biofilm formation phenomenon of Labrenzia sp. PO1, as the formation was observed only in PO1.

An accurate tensor estimation function is a guarantee for acquiring a reliable underground electrical structure model. The past studies regarding transmission functions aim at obtaining smooth and continuous sounding curves through the time domain by data screening means such as least square, robust and remote reference processing methods as well as digital filtering techniques such as wavelet denoising, empirical mode decomposition and Hilbert–Huang transform denoising. As SNRs in different field measurement sites are different, if different data processing algorithms like single-site processing, remote reference processing, magnetic field correlation-based remote reference processing and magnetic channel sharing are used for data processing at the same measuring site, 3N-2 groups of sounding curves with different qualities will be obtained. Manual screening method has been mainly used in the past for screening of the abovementioned 3N-2 groups of sounding curves. If the quantity of sounding site is large, this manual screening method is of low efficiency without quantitative screening indexes. In this paper, discrete Frechet distance is mainly utilized to carry out quantitative screening of 3N-2 groups of sounding curves processed through the abovementioned four processing methods in order to obtain smooth, continuous and reliable sounding curves, thus avoiding subjectivity and low efficiency problems in the past manual screening. A quantitative sorting of all kinds of data processing results can be conducted, and the optimal sounding curve is finally picked out for data inversion. The above sounding curve selection result has improved processing accuracy of magnetotelluric data.

—A new asplenioid fern species, Asplenium simaoense (Aspleniaceae), found growing on an exposed slope of a limestone mountain in southwestern Yunnan, China, is described and illustrated. A preliminary phylogenetic analysis showed that A. simaoense is strongly supported as sister to A. tenuifolium, whereas A. simaoense is morphologically most similar to A. varians and A. sarelii. However, A. simaoense has rhizome scales entire and petioles (5‐)12‐20(‐25) cm, while A. varians has rhizome scales subentire or fimbriate and petioles (0.5‐)2‐7(‐12) cm and A. sarelii has rhizome scales denticulate and petioles 7‐10 cm. Only one population of A. simaoense was found near a road. Its habitat is threatened by road construction and therefore it is recommended to be classified as CR, Critically Endangered, following IUCN red list criteria.

The infrageneric relationships and taxonomy of the largest fern genus, Asplenium (Aspleniaceae), have remained poorly understood. Previous studies have focused mainly on specific species complexes involving a few or dozens of species only, or have achieved a large taxon sampling but only one plastid marker was used. In the present study, DNA sequences from six plastid markers (atpB, rbcL, rps4, rps4-trnS, trnL and trnL-F) of 1030 accessions (616 of them newly sequenced here) representing c. 420 species of Asplenium (60% of estimated species diversity), 16 species of Hymenasplenium, three Diplaziopsidaceae, and four Rhachidosoraceae were used to produce the largest genus-level phylogeny yet for ferns. Our major results include: (i) Asplenium as broadly circumscribed is monophyletic based on our inclusion of representatives of 32 of 38 named segregate genera; (ii) 11 major clades in Asplenium are identified, and their relationships are mostly well-resolved and strongly supported; (iii) numerous species, unsampled in previous studies, suggest new relationships and numerous cryptic species and species complexes in Asplenium; and (iv) the accrued molecular evidence provides an essential foundation for further investigations of complex patterns of geographical diversification, speciation and reticulate evolution in this family.

The Baogutu porphyry copper deposit is a typically reduced porphyry copper deposit (RPCD), characterized by reduced, calc-alkaline, felsic shallow intrusions. A newly discovered gabbro, which contains 1182–1260 ppm Cu, provides an ideal window to reveal the genesis and formation of the Baogutu RPCD. A combined study of the petrological, geochronological, geochemical and isotopic characteristics of the Cu-bearing gabbro and granitoids in the Baogutu RPCD has been completed. The laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) U-Pb dating of zircons from a gabbro, diorite and porphyritic diorite are 318.2 ± 0.8 Ma (MSWD = 0.01, n = 16), 315.8 ± 1.0 Ma (MSWD = 1.50, n = 16), and 314.9 ± 0.6 Ma (MSWD = 0.12, n = 20), respectively. The geochemical and isotopic characteristics of the gabbro, diorite, and porphyritic diorite at Baogutu RPCD are all metaluminous, calc-alkaline series rocks with depletion in Nb, Ta, and Ti and enrichment in light rare earth elements (LREE) and large ion lithophile elements consistent with an arc-related setting. The relatively high Nd and Hf isotopes (eNd(t) = +6.9 to +7.5, eHf(t) = +8.8 to +14.4) and wide variations of major and trace elements suggest that the gabbro and diorite in the Baogutu RPCD were all derived from a mixture of melts of metasomatized mantle wedge, the hydrous slab, and old crustally derived materials. The high Mg andesites (HMA)/sanukite features (high Mg#, Cr and Ni content) of the gabbro suggest it was derived mainly from a metasomatized mantle-hydrous slab-derived melt source with only slightly contamination by the old crustal materials, whereas adakitic features of the diorite (high Al2O3 and Sr contents and Sr/Y ratios) suggest a greater role the melting of residual subducted oceanic crust with juvenile mantle materials. The porphyritic diorite, which inherited the geochemical characteristics of diorite, was probably derived from a similar parental magma but the low eNd(t) of +1.4, old T2DM (Nd) age of 961 Ma and enrichment in Zr and Hf suggest a greater degree of crustal contamination. The high content of Cu and high oxidation state of the gabbro is consisted with it having formed early from an unusually Cu-rich parental magma. This magma would have provided abundant metal and sulfides which would have been mobilized and reconcentrated by later ore bearing fluids linked to the intermediate to acid porphyry intrusions in the Baogutu RPCD.

A new Chinese species of the genus Linan Hlaváč, 2003, L.qiniangmontissp. nov., is described based on two male and three female specimens from sifted leaf litter samples at Qiniang Mountain, Shenzhen City, Guangdong. The species can be readily recognized and separated from all congeners based on the forms of the male antennae, the metaventral processes, and the aedeagus.

A series of samples including natural gas, formation water, and rocks were collected from volcanic rock reservoirs in the Niudong area of the Santanghu Oilfields and analyzed for their mineral and/or chemical compositions and sulfur and carbon isotopes in order to investigate the occurrence and origin of hydrogen sulfide (H2S). H2S was mostly dissolved in the formation water along with petroleum production in the study area. The δ34S values of on-well H2S samples varied in a range of 9.2‰ to 20.5‰, probably indicating thermochemical sulfate reduction (TSR) and/or thermal decomposition of organic sulfur-bearing compounds (TDS) as the genetic process for H2S. However, the chemical composition of formation waters from the Kalagang Formation (C2k) and their coefficient of desulfurization also revealed that TSR could be the main principle for H2S formation. Considering the regional geological background, especially the tectonic structures and thermal evolution features of the basin, it was concluded that H2S in the study area was dominantly produced by thermal genesis with TSR as a domain through interactions between hydrocarbons and aqueous sulfate dissolved from sulfate minerals.

The Sino-Korean Craton, which is part of the Columbia supercontinent, was originally formed and stabilized by the amalgamation of several distinctly different tectonic units during the Paleoproterozoic period. Although the early tectonic framework of the Sino-Korean Craton remains controversial, the Paleoproterozoic Jiao-Liao-Ji Belt is accepted to divide the eastern unit of this craton into Archean Nangrim-Liaonan and Longgang blocks. This orogenic belt is thus the key to revealing the geodynamic processes that occurred during the assemblage and breakup of the Paleoproterozoic supercontinent Columbia. Due to late polyphase tectonothermal events (e.g., subduction of the paleo-Pacific Plate), considerable and continuing controversy has surrounded how this Paleoproterozoic orogenic belt formed, with models including (1) opening and closing of an intracontinental rift, (2) collision of a continent–arc–continent system, (3) a rifting–initial ocean formation–oceanic subduction–collision cycle, and (4) opening and closure of a back-arc basin or retro-arc foreland basin. Here, we synthesize the geochronological, geochemical, and isotopic data on the Paleoproterozoic igneous rocks in the JLJB. The available data suggest that the Paleoproterozoic magmatism in the JLJB lasted from ca. 2200 Ma to ca. 1800 Ma, with five magmatic flare-ups at ca. 2190–2160 Ma, ca. 2160–2110 Ma, ca. 2110–2080 Ma, ca. 2010–1895 Ma and ca. 1875–1850 Ma. These data, in combination with previous studies on voluminous meta-sedimentary rocks, Archean basement relict slices and granitic leucosomes within the JLJB, allow us to reconstruct the tectonic evolution of the JLJB based on rock petrogenesis as described below. (1) During the early stage of northwestward subduction of Paleoproterozoic oceanic plate between the Longgang-Liaonan-Nangrim Block (i.e., the Eastern Block) and the West Australian Craton (WAC) and/or North Australian Craton (NAC), strong slab rollback resulted in trench retreat and extension of the overriding plate (i.e., the Longgang-Liaonan-Nangrim Block) and induced upwelling and decompression melting of asthenospheric mantle to produce basaltic magma. The overriding Archean continental crust was heated by the underlying basaltic magma and melted to produce ~2190–2160 Ma aluminous A2-type granites, and minor basaltic magma mixed with this crustal melt to form ~2180–2160 Ma calc-alkaline, andesitic-rhyolitic tuffs. (2) With ongoing extension, the overriding plate thinned, and a back-arc basin opened and widened. The asthenospheric mantle that was metasomatized by limited subduction-related fluids and/or melts began to melt in the spinel-garnet stability field, and produced ~2160–2110 Ma tholeiitic mafic rocks with the geochemical features of both mid-oceanic ridge basalt (MORB) and volcanic arcs. (3) Decreased back-arc mafic magmatism suggests that subduction ceased due to collision between the WAC and/or NAC and the active subduction zone during ~2110–2080 Ma. After the collision, the subduction polarity reversed, from northwestward to southeastward, forming new subduction initiation in the southeastern margin of the back-arc basin, and this new subduction further resulted in forearc extension. Decompression melting of the subarc mantle produced basaltic magma, which was metasomatized by subducted slab- and ancient sediment-derived melts to form ~2110–2080 Ma mafic rocks with both calc-alkaline and tholeiitic features. Simultaneously, the overriding continental crust was heated by the basaltic magma and melted to form ~2110–2080 Ma aluminous A2-type granites. These processes, including opening and closure of back-arc basin, were accompanied by the deposition of voluminous sedimentary rocks in this back-arc basin, and the deposition lasted for at least 180 Myr. (4) After the collision between the WAC and/or NAC, the arc terrane (Nangrim-Liaonan Block + Gyeonggi massif?) and the Longgang Block, the orogeny that involved Archean basement rocks, Paleoproterozoic sedimentary rocks and associated mafic and granitic intrusions began. This process was accompanied by prograde or peak metamorphism and minor magmatism, which produced the ~2000–1895 Ma adakitic granites derived from partial melting of thickened lower crust. (5) During the late Paleoproterozoic, termination of the collisional orogenic event occurred, as evidenced by strong postcollisional extension, which generated widespread ~1875–1850 Ma igneous rocks in the JLJB and was accompanied by a regional partial melting event related to the exhumation of the JLJB. In summary, the five stages of magmatism, and associated sedimentation and metamorphism in the JLJB record a complete tectonic cycle, including oceanic plate subduction, back-arc extension, closure of the back-arc basin, collisional orogeny and postcollisional extension. These processes further support the conclusion that plate tectonic processes in the Paleoproterozoic period resulted in the amalgamation of microcontinents and arcs to form the Sino-Korean Craton and the Columbia supercontinent.

The Micro-Resistive WELL ( μ RWELL) detector is a novel spark-protected Micro-Pattern Gaseous Detector (MPGD) with a single well-type amplification stage. By integrating a well-type amplification structure with a resistive electrode on a readout board ( μ RWELL PCB), the μ RWELL detector is only composed of a cathode PCB and a μ RWELL PCB, resulting in a very simple assembling process without any gluing, stretching, tensioning or other complicated operation commonly practiced in assemblies of other MPGDs. A critical component of the μ RWELL detector is the resistive electrode that is responsible for spark suppression, and hence maintains stable operation of the detector. In this paper, we present a 10 cm × 10 cm μ RWELL detector with two layers readout strips perpendicular to each other. Its resistive electrode is made of a thin coating of Diamond-Like Carbon by magnetron sputtering technique. The gain performance and rate capability of this μ RWELL detector were systematically studied with X-rays, and its detection efficiency and spatial resolution were measured with a test beam. The detector can achieve a spatial resolution better than 70 μ m in both dimensions while the detection efficiency is higher than 90%.

With the large-scale construction of high-speed railway bridges, monitoring their settlement has become an increasingly important task to ensure the safe operation of a high-speed railway. This paper presents a case study of a 100-km-long portion of an intelligent settlement monitoring system for the high-speed railway bridges (SMAIS) of the Beijing–Shanghai railway. The SMAIS consists of a sensor subsystem (SS), data acquisition and transmission subsystem (DAQ), data processing and analysis subsystem (DPA), database subsystem (DB), and data display and early warning subsystem (DEW). The SMAIS has the advantages of modularisation, low coupling, and interface standardisation. The general design principles of the SMAIS were studied, including its monitoring range calculation, monitoring point positions, and early warning threshold value determination. Proposals are made for the design of the SMAIS architecture and functions of its subsystems. The installation process and standard techniques for the SMAIS are also presented. The sensor precision test, temperature stability test, and general monitoring results are presented. An advanced continuous median data filtering-algorithm that considers the vehicle influence and error transmission is proposed.

A novel microemulsion is developed at room temperature with 30 µL of sodium alginate sulfate (SAS, 0.02 mol/L), 0.005 g bis (2-ethylhexyl) succinate sulfonate (AOT) and 270 µL of 1-butyl-3-methylimidazolium hexafluorophosphate (BmimPF6) ionic liquid as aqueous phase, surfactant and IL phase, respectively. The SAS/AOT/BmimPF6 microemulsion significantly improves the extraction efficiency for low density lipoprotein (LDL). 96% LDL in a 300 µL of PBS is selectively extracted into a same volume of microemulsion, with respect to those of 67%, 76% and 85% by BmimPF6, H2O/AOT/BmimPF6 microemulsion and sodium alginate (SA)/AOT/BmimPF6 microemulsion. LDL in the SAS/AOT/BmimPF6 microemulsion is distributed both in BmimPF6 via hydrophobic interaction and in the “pools” of the microemulsion via electrostatic interaction with AOT and specific interaction between LDL with SAS. 83% of LDL in the microemulsion can be readily back extracted into an aqueous phase with 0.8% (m/v) of sodium dodecyl sulfate (SDS) as stripping reagent. For practical applications, LDL in human serum is selectively extracted with the microemulsion, as demonstrated by enzyme linked immunosorbent assay (ELISA) and sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE).

The Eastern Block of the North China Craton records Paleoproterozoic oceanic plate subduction, the opening and subsequent closure of a back-arc basin, and a following collisional orogenic e...

The recently discovered giant Huoshaoyun zinc-lead deposit in the Karakorum Range, northwestern Tibet, China, consists of a major zinc-lead carbonate and a minor lead-dominant sulfide mineralization with metal reserves of zinc and lead of over 16 million tonnes. The zinc-lead carbonate mineralization is composed of smithsonite and cerussite, with laminated, massive, veined and botryoidal textures, showing sedimentary and metasomatic structures. The lead-dominant sulfide mineralization is composed mainly of galena and minor sphalerite and pyrite, with laminated, brecciated, and veined textures. The laminated sulfide mineralized zones occur at the top of the deposit, whereas the zinc-lead carbonate mineralized bodies are located below the sulfide zones. Lead-dominant sulfide veins cut the zinc-lead carbonate ores and the host limestone. The sequence of formation of the lead-zinc ores with various mineral colors in thin sections is as follows: (1) light-colored to yellowish, fine- to coarse- and subhedral to euhedral smithsonite; (2) yellowish to reddish, fine- to coarse- and subhedral to euhedral smithsonite; (3) light-colored veined smithsonite; (4) white coarse-grained, xenomorphic cerussite; (5) colorless euhedral to sub-angular quartz crystals; (6) euhedral to anhedral lead-zinc sulfides and gypsum. The mineralization events of the Huoshaoyun deposit are: (1) early hydrothermal sedimentary smithsonite mineralization; (2) hydrothermal replacive smithsonite mineralization; (3) vein-type smithsonite mineralization; (4) open space filling and replacive cerussite mineralization; (5) lead-zinc sulfide mineralization. The fluid inclusions of cerussite indicate that the hydrothermal fluids of the cerussite ore-forming stage are characterized by a temperature range of at least 186–206 °C and low salinities (0.7–1.2 wt% NaCl eq.). The source of oxygen and carbon for the zinc-lead carbonate mineralization is possibly consistent with the involvement of marine water and a magmatic fluid, and is probably dominated by the magmatic fluid. The source of sulfur for the lead-dominant sulfide mineralization is possibly related to a magma reservoir. The zinc-lead-carbonate portion of the deposit represents a primary hypogene non-sulfide mineralization.

Polar surfaces of ferroelectric oxides are of great importance for both fundamental and practical interest. In this report, we present a theoretical study to determine the thermodynamic stability and electronic properties of ferroelectric BiAlO3(0001) surfaces. According to the calculated surface phase diagram, we predict that the equilibrium stoichiometries are distinct for the oppositely polarized BiAlO3 surfaces under the same chemical conditions. In addition to nonstoichiometry of the surface chemical compositions, we find that anomalous filling of the surface states can also result in surface metallization in order to compensate the remarkable surface polarity. Besides providing atomic-scale understanding of the BiAlO3(0001) surfaces, we also put forward the practical implications in novel magnetoelectric devices and advanced surface chemistry.

A new model for a thermoacoustic transducer array with high acoustic beam directivity applying devised carbon nanotube (CNT) thin films is developed. Analytical exact solutions of acoustic pressure...

Biobased cationic waterborne polyurethanes (WPUs) were prepared using isophorone diisocyanate (IPDI), N-methyl diethanolamine (N-MDEA), polycaprolactone (PCL) diol, hydrochlotic acid (HCl), and 1,4-butanediol (BDO). To improve the mechanical performance and adhesive strength of the waterborne polyurethane films, different amounts of castor oil (CO) acting as a cross-linking agent were incorporated in the polyurethane structure. The structures of the waterborne polyurethanes were assessed by Fourier-transform infrared spectroscopy (FTIR). The combination of CO had a positive effect on the dispersion and stability properties of WPUs. WPUs containing higher content of CO demonstrated a remarkable enhancement in homogeneity among particles. The stable aqueous dispersion was obtained even when N-MDEA loading was as low as 3.2 wt%, a bonus of this low hydrophilic moiety was the excellent adhesive strength, whose T-peel strength could reach up to 36.8 N/25 mm, about 114% higher than that of WPU (17.2 N/25 mm) without any CO content. The elongation at break of CO7.40%-WPU was 391%. In addition, the fracture mechanism of the waterborne polyurethane films transformed from the brittle failure to the ductile fracture. The experiment results showed the CO-modified WPUs displayed excellent film-forming property, flexibility, and adhesion, which can be employed for constructing the eco-friendly, biodegradable, cationic, waterborne polyurethanes.

Municipal wastewater treatment plants (WWTPs) use functional microorganisms in activated sludge (AS) to reduce the environmental threat posed by wastewater. In this study, Illumina NovaSeq sequencing of 16S rRNA genes was performed to explore the microbial communities of AS at different stages of the two WWTP projects in Shenzhen, China. Results showed that Proteobacteria, Bacteroidetes, Acidobacteria, Firmicutes, and Nitrospirae were the dominant phyla in all the samples, with Proteobacteria being the most abundant and reaching a maximum proportion of 59.63%. There was no significant difference in biodiversity between the two water plants, but Stage 1 and Stage 2 were significantly different. The Mantel test indicated that nitrate, total nitrogen (TN), chemical oxygen demand (COD), and nutrients were essential factors affecting the bacterial community structure. FAPROTAX analysis emphasized that the leading functional gene families include nitrification, aerobic nitrite oxidation, human pathogens, and phototrophy. This study reveals changes in the community structure of AS in different treatment units of Banxuegang WWTP, which can help engineers to optimize the wastewater treatment process.

Simple Summary Forensic entomologists utilize sarcosaprophagous insect species to estimate the postmortem interval to aid death investigations. In this paper, we present the recent chronology of forensic entomology in China and illustrate how identification, development, and succession data are obtained and applied at the scale of such a large country. To overcome the difficulties and challenges forensic entomology faces in China, a number of countermeasures are provided. Abstract While the earliest record of forensic entomology originated in China, related research did not start in China until the 1990s. In this paper, we review the recent research progress on the species identification, temperature-dependent development, faunal succession, and entomological toxicology of sarcosaprophagous insects as well as common applications of forensic entomology in China. Furthermore, the difficulties and challenges forensic entomologists face in China are analyzed and possible countermeasures are presented.

Two kinds of analytical solutions are derived through Laplace transform for the equation that governs wave-induced suspended sediment concentration with linear sediment diffusivity under two kinds of bottom boundary conditions, namely the reference concentration (Dirichlet) and pickup function (Numann), based on a variable transformation that is worked out to transform the governing equation into a modified Bessel equation. The ability of the two analytical solutions to describe the profiles of suspended sediment concentration is discussed by comparing with different experimental data. And it is demonstrated that the two analytical solutions can well describe the process of wave-induced suspended sediment concentration, including the amplitude and phase and vertical profile of sediment concentration. Furthermore, the solution with boundary condition of pickup function provides better results than that of reference concentration in terms of the phase-dependent variation of concentration.

The design and synthesis of low-cost and highly efficient bifunctional catalysts is an inevitable path for rechargeable zinc-air batteries (rZABs). In this work, double-carbon co-supported Co-based oxide with the Cu and S substitutions are synthesized by a one-step hydrothermal method and formed a unique honeycomb structure. As expected, the (Cu, Co)3OS3@CNT-C3N4 exhibits high oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) activity with low overpotential (0.86 V), high power density (215 mW cm-2), and long-term discharge stability (115 h). The (Cu, Co)3OS3@CNT-C3N4-based rZAB also shows a stronger charge-discharge durability with a very low voltage gap of merely 0.5 V than that of Pt/C+RuO2. The high catalytic performances are attributed to these following reasons: (i) the porous morphology and hierarchical structure with plentiful "catalytic buffer", which accelerates the mass transfer; (ii) a high-speed electronic transmission network established by C3N4 and carbon nanotube (CNT), enhancing the conductivity; (iii) the strong synergistic effect between (Cu, Co)3OS3@CNT and C3N4, which improves the kinetics of ORR/OER; and (iv) the controllable occupation of Cu ions and S ions, which effectively regulates the CoO6 surface and increases the active site density. This work not only offers a promising ORR/OER electrode for rZAB but also provides a new pathway to understand the improvement mechanism for catalysts by the bi-ion substitutions.

With the development of society, the problem of energy shortage and environmental pollution is becoming more and more prominent. However, the phenomenon of permanent lights still exists in office buildings. At present, the lighting power consumption accounts for about 10% of the total power consumption in China. Therefore, it is necessary to research and develop intelligent lighting control systems asy to implement for energy-saving. Meanwhile, it is necessary to make full use of natural light sources to meet the demand of office illumination. In this paper, the intelligent dimming algorithm forlighting group control is studied, which transforms room size and the location information of lighting & work station into two-dimensional coordinate data on the lighting plane. According to the illuminance contribution value and illuminance superposition law of point light sources in a certain work station, the linear programming optimization algorithm is used to calculate the dimming coefficient of each lamp for meeting the illuminance demand of each office work station and with the energy consumption of indoor lighting as the optimal objective as well. The simulation results show that compared with the existing lighting control methods, the proposed illumination control scheme can effectively meet the illumination requirements of offices, and save more than 30% energy.

Zr-based metal-organic framework, UiO-66-NH2, provides favorable adsorption capacity to phosphoproteins, however, it exhibits obvious nonspecific adsorption to other proteins. In the present work, we report a facile strategy to reduce the nonspecific adsorption of nonphosphoproteins by modifying UiO-66-NH2 with imidazolium ionic liquids (ILs). With respect to bare UiO-66-NH2, the modified counterpart, UiO@IL, exhibits much improved selectivity to phosphoproteins while maintains comparable adsorption performance. The surface of UiO@IL presents a strong hydrophilicity due to the modification of ILs. Hydrophobic and electrostatic interaction between the absorbent and nonphosphoprotein is significantly reduced. In addition, the interaction between imidazole group of ILs moiety and phosphate group in phosphoprotein ensures the favorable adsorption capacity of UiO@IL for phosphoproteins. Anionic moieties of ILs, i.e., Cl−, Br−, BF4−, CF3SO3−, play negligible effect in the adsorption process. As a representative, phosphoprotein β-casein (β-ca) is selectively enriched at a mass ratio of BSA:β-ca = 100:1. UiO@IL was further applied for the selective enrichment of phosphoprotein in milk.

In this study, a laser remelting process was applied to the FeCrCoNiTiAl0.6 high entropy alloy coating in order to improve the density and the surface quality of the coating. The coating was fabricated by high-velocity-oxygen-fuel (HVOF) technology. The microstructure and phase composition of the coating were investigated by scanning electron microscopy (SEM), energy dispersive X-ray spectrometer (EDS), X-ray diffractometer (XRD) and confocal scanning laser microscope (CSLM). Moreover, the wear behavior of the coating was evaluated by use of a ball-on-disc test. The coating was denser after laser remelting treatment by eliminating the previous lamellar structure. The microstructure of the laser-remelted coating exhibits two body-centered cubic (BCC) phases, which is different from the HVOF coating. In addition, aluminum oxide formed during laser remelting. Different from the wear mechanism of the HVOF coating, which comprised abrasion and fatigue, the major wear of the laser remelted coating was abrasion.

Thermally activated delayed fluorescent (TADF) materials, as the third generation of organic electroluminescent materials, have many advantages over other organic light-emitting diodes (OLEDs) materials, such as 100% internal quantum efficiency, no doping of heavy metals, and avoiding the shortages of ordinary fluorescent materials and phosphorescent materials. So it is considered to be the most competitive organic light-emitting materials, and has great application prospects in the field of OLEDs. So far, small-molecule TADF materials have achieved high quantum yield and full-color range of red, green, and blue. However, TADF polymers suitable for low-cost and easily scalable solution processing are less developed, which are confined by the preparation methods and polymers designing, and there are still challenges of increasing quantum efficiency and strengthening device performance. This review mainly summarizes different synthesis strategies of TADF polymers and the latest development in the field. Special attention is focused on illustrating the designing and structure-property relationship of TADF polymers, and finally, an outlook is given for the design and application prospect of TADF polymers in the future.

Real-time users cannot carry out real-time precise point positioning (RT-PPP) because they cannot receive real-time service (RTS) products from the international GPS service (IGS) in the case of interrupted communication. We address this issue by introducing a stable particle swarm optimized wavelet neural network (PSOWNN) to predict the short-term satellite clock bias in real time accurately. The predicted sequences of the new model are compared with those of the conventional linear polynomial, quadratic polynomial, gray system (GM (1,1)), and Kalman filter models. The results show that the accuracy of the proposed model is better than that of these four models. The average prediction accuracy of the 30-min and 60-min forecasting has improved by approximately (79.3, 82.4, 79.1, 97.4) % and (97.4, 82.9, 87.7, 98.9) % and is better than 0.3 ns during 30-min and 1-h forecasting. The RTS products can thus be replaced with the short-term clock products predicted by the PSOWNN model to meet the precision requirements of RT-PPP.

As a consequence of hybridization, polyploidization, and apomixis, the genus Cotoneaster (Rosaceae) represents one of the most complicated and controversial lineages in Rosaceae, with ca. 370 species which have been classified into two subgenera and several sections, and is notorious for its taxonomic difficulty. The infrageneric relationships and taxonomy of Cotoneaster have remained poorly understood. Previous studies have focused mainly on natural hybridization involving only several species, and phylogeny based on very limited markers. In the present study, the sequences of complete chloroplast genomes and 204 low-copy nuclear genes of 72 accessions, representing 69 species as ingroups, were used to conduct the most comprehensive phylogenetic analysis so far for Cotoneaster. Based on the sequences of complete chloroplast genomes and many nuclear genes, our analyses yield two robust phylogenetic trees respectively. Chloroplast genome and nuclear data confidently resolved relationships of this genus into two major clades which largely supported current classification based on morphological evidence. However, conflicts between the chloroplast genome and low-copy nuclear phylogenies were observed in both the species level and clade level. Cyto-nuclear discordance in the phylogeny could be caused by frequent hybridization events and incomplete sorting lineage (ILS). In addition, our divergence-time analysis revealed an evolutionary radiation of the genus from late Miocene to date.

Unprecedented high-rise buildings pose new challenges for earthquake engineering. Full-field structural health monitoring (SHM) systems have flourished to address these challenges. In this ...

This paper presents a useful concept/tool, i.e., Chasles' motion sphere (CMSphere), that is able to visually express the motion characteristics over the workspace and capable of investigating the local motion performance of the end-effector of robotic mechanisms. The process of CMSphere generation is in line with people's habit of observing a mechanism. Under a researched pose, give a small pose change to the end-effector by translating with a small length or rotating with a small angle along a direction, then the corresponding Chasles' motion of the small pose change can be calculated. Two key parameters of Chasles' motion, the pitch and the position of the Chasles' axis, are chosen to represent the motion characteristics. This kind of mathematical operation can be carried along many directions to obtain a distribution of the motion characteristics at the researched pose, which can be drawn as a sphere. To illustrate this tool, Robotic Mechanisms with Three Independent Pose Variables (RMTIPVs) are discussed as the research objects. Three categories of RMTIPVs based on the types of independent pose variables are given. For each category, the detailed process of CMSphere generation is discussed. The 3R series mechanism, Tricept, and 3-RPS (the limb consisting of one revolute, one prismatic and one spherical joints) parallel mechanism are used as examples to demonstrate the methodology.