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The tether deployment of a tethered satellite system involves the consideration of complex dynamic properties of the tether, such as large deformation, slack, and even rebound, and therefore, the dynamic modelling of the tether is necessary for performing a dynamic analysis of the system. For a variable-length tether element, the absolute nodal coordinate formulation (ANCF) in the framework of the arbitrary Lagrange-Euler (ALE) description was used to develop a precise dynamic model of a tethered satellite. The model considered the gravitational gradient force and Coriolis force in the orbital coordinate frame, and it was validated through numerical simulation. In the presence of dynamic constraints, a deployment velocity of the tether was obtained by an optimal procedure. In the simulation, rebound behavior of the tethered satellite system was observed when the ANCF-ALE model was employed. Notably, the rebound behavior cannot be predicted by the traditional dumbbell model. Furthermore, an improved optimal deployment velocity was developed. Simulation results indicated that the rebound phenomenon was eliminated, and smooth deployment as well as a stable state of the station-keeping process were achieved. Additionally, the swing amplitude in the station-keeping phase decreased when a deployment strategy based on the improved optimal deployment velocity was used.

The locally occurring mechanisms of hydrogen embrittlement significantly influence the fatigue behavior of a material, which was shown in previous research on two different AISI 300-series austenitic stainless steels with different austenite stabilities. In this preliminary work, an enhanced fatigue crack growth as well as changes in crack initiation sites and morphology caused by hydrogen were observed. To further analyze the results obtained in this previous research, in the present work the local cyclic deformation behavior of the material volume was analyzed by using cyclic indentation testing. Moreover, these results were correlated to the local dislocation structures obtained with transmission electron microscopy (TEM) in the vicinity of fatigue cracks. The cyclic indentation tests show a decreased cyclic hardening potential as well as an increased dislocation mobility for the conditions precharged with hydrogen, which correlates to the TEM analysis, revealing courser dislocation cells in the vicinity of the fatigue crack tip. Consequently, the presented results indicate that the hydrogen enhanced localized plasticity (HELP) mechanism leads to accelerated crack growth and change in crack morphology for the materials investigated. In summary, the cyclic indentation tests show a high potential for an analysis of the effects of hydrogen on the local cyclic deformation behavior., Forschungsvereinigung Verbrennungskraftmaschinen, Deutsche Forschungsgemeinschaft

We present a new variant of the Chambolle–Pock primal–dual algorithm with Bregman distances, analyze its convergence, and apply it to the centering problem in sparse semidefinite programming. The novelty in the method is a line search procedure for selecting suitable step sizes. The line search obviates the need for estimating the norm of the constraint matrix and the strong convexity constant of the Bregman kernel. As an application, we discuss the centering problem in large-scale semidefinite programming with sparse coefficient matrices. The logarithmic barrier function for the cone of positive semidefinite completable sparse matrices is used as the distance-generating kernel. For this distance, the complexity of evaluating the Bregman proximal operator is shown to be roughly proportional to the cost of a sparse Cholesky factorization. This is much cheaper than the standard proximal operator with Euclidean distances, which requires an eigenvalue decomposition.

Publisher Copyright: © 2021 The Authors. Published by American Chemical Society The global prevalence of antibiotic resistance genes (ARGs) is of increasing concern as a serious threat to ecological security and human health. Irrigation with sewage and farmland application of manure or biosolids in agricultural practices introduce substantial selective agents such as antibiotics and toxic metals, aggravating the transfer of ARGs from the soil environment to humans via the food chain. To address this issue, a hyperaccumulator (Sedum plumbizincicola) combined with biochar amendment was first used to investigate the mitigation of the prevalence of ARGs in cadmium and oxytetracycline co-contaminated soil by conducting a pot experiment. The addition of biochar affected the distribution of ARGs in soil and plants differently by enhancing their prevalence in the soil but restraining transmission from the soil to S. plumbizincicola. The planting of S. plumbizincicola resulted in an increase in ARGs in the soil environment. A structural equation model illustrated that mobile genetic elements played a dominant role in shaping the profile of ARGs. Taken together, these findings provide a practical understanding for mitigating the prevalence of ARGs in this soil system with complex contamination and can have profound significance for agricultural management in regard to ARG dissemination control.

Tremendous demands for highly sensitive and stable seawater salinometers have motivated intensive research on advanced electrode materials. Boron-doped diamond (BDD) is attractive in terms of its high mechanical stability and chemical inertness, but is usually hindered by its low double-layer capacitance (Cdl) for seawater salinity detection. Here, inspired by the principle of oxygen-terminated BDD electrode endowing higher Cdl than hydrogen-terminated surface, we introduce the oxygen terminated surface by oxygen plasma or reactive ion etch (RIE), and the fabricated oxygen terminated BDD electrodes demonstrate high sensitivity and long-term stability in seawater salinity detection comparing with the hydrogen terminated BDD electrodes. Significantly, the as-fabricated O-BDD-RIE electrodes not only show remarkable enhanced response even better than the commercial platinum black electrodes but also display long-time stability which is weekly verified by continuous monitor for 90 days. The outstanding performance of the oxygen terminated BDD electrodes can be ascribed to the enhancement of C-O surface functional group on Cdl. In addition, a comprehensive analysis of effective electroactive surface area (EASA) and Cdl proves that the surface oxygen is the major factor for the improved Cdl. In summary, the excellent oxygen terminated BDD electrodes promise potential application in seawater salinity detection.

Synthetic aperture radar (SAR) has great potential for timely monitoring of flood information as it penetrates the clouds during flood events. Moreover, the proliferation of SAR satellites with high spatial and temporal resolution provides a tremendous opportunity to understand the flood risk and its quick response. However, traditional algorithms to extract flood inundation using SAR often require manual parameter tuning or data annotation, which presents a challenge for the rapid automated mapping of large and complex flooded scenarios. To address this issue, we proposed a segmentation algorithm for automatic flood mapping in near-real-time over vast areas and for all-weather conditions by integrating Sentinel-1 SAR imagery with an unsupervised machine learning approach named Felz-CNN. The algorithm consists of three phases: (i) super-pixel generation; (ii) convolutional neural network-based featurization; (iii) super-pixel aggregation. We evaluated the Felz-CNN algorithm by mapping flood inundation during the Yangtze River flood in 2020, covering a total study area of 1,140,300 km2. When validated on fine-resolution Planet satellite imagery, the algorithm accurately identified flood extent with producer and user accuracy of 93% and 94%, respectively. The results are indicative of the usefulness of our unsupervised approach for the application of flood mapping. Meanwhile, we overlapped the post-disaster inundation map with a 10-m resolution global land cover map (FROM-GLC10) to assess the damages to different land cover types. Of these types, cropland and residential settlements were most severely affected, with inundation areas of 9,430.36 km2 and 1,397.50 km2, respectively, results that are in agreement with statistics from relevant agencies. Compared with traditional supervised classification algorithms that require time-consuming data annotation, our unsupervised algorithm can be deployed directly to high-performance computing platforms such as Google Earth Engine and PIE-Engine to generate a large-spatial map of flood-affected areas within minutes, without time-consuming data downloading and processing. Importantly, this efficiency enables the fast and effective monitoring of flood conditions to aid in disaster governance and mitigation globally.

A new genus and species, Termitocnemis huangi gen. et sp. nov., of the tenebrionine tribe Amarygmini Gistel, 1848 is described from Fujian Province, southeastern China. All specimens were collected from a healthy nest of the termite genus Nasutitermes Dudley, 1890, implying that this species is truly termitophilous. Transitional habitus characters of the new species shed further light on the evolution of amarygmine beetles from free-living to termitophily. Given the discovery of this new genus a revised key is provided to the Oriental genera of termitophilous Amarygmini.

Fiber Bragg grating (FBG) array, consisting of a number of sensing units in a single optical fiber, can be practically applied in quasi-distributed sensing networks. Serious signal crosstalk occurring between large-serial of identical FBGs, however, has limited the further increase in the number of sensing units, thus restricting applications only for short-distance sensing networks. To reduce the signal crosstalk, we design two novel types of 10-kilometer-long FBG arrays with 10 000 equally spaced gratings, written on-line using a customized grating inscription system, which is affiliated to a drawing tower. Main factors causing signal crosstalk, such as spectral shadowing and multiple reflections, are firstly investigated in theory. Consistent with the theoretical findings, experimental results are proving that ultra-weak (the reflectivity of ∼−40 dB) and multi-wavelength gratings of a number more than 10 000 can be readily identified, with satisfied low crosstalk. The maximum attenuation of grating signal and minimum signal-to-noise ratio (SNR) in a single-wavelength array are 10.69 dB and 5.62 dB, respectively. As a comparison, by increasing the number of central wavelengths to three, the attenuation can be effectively reduced to 5.54 dB and the minimum SNR has been improved to 8.14 dB. The current study significantly enhances the multiplexing capacity of FBG arrays and demonstrates promising potentials for establishing large-capacity quasi-distributed sensing networks.

Fluorescence and phosphorescence are known as two kinds of fundamental optical signals, which have been used for myriad applications. Of particular note, simultaneous activation of stable fluorescence and long-lived room temperature phosphorescence (RTP) emission in aqueous phase remains a big challenge up to present. Herein, we prepare a kind of zinc-doped silica nanospheres (Zn@SiNSs) with fluorescence and RTP properties through a facile hydrothermal synthetic strategy. For the as-prepared Zn@SiNSs, the recombination of electrons and holes in defects and defect-stabilized excitons derived from oxygen vacancy/C=N bonds lead to the production of stable fluorescence and long-lived RTP (emission lasting for ~9 s, quantum yield (QY): ~33.6%, RTP lifetime: ~236 ms). In addition, the internal Si-O bonded networks and hydrophilic surface in Zn@SiNSs can reduce nonradiative decay to form self-protective RTP, and also provide high water solubility, excellent pH- and photo-stability.

Side deep placement of nitrogen plays an important role in improving rice yield and nitrogen use efficiency. Few studies have examined the effects of reducing the times of nitrogen (RTN) application and reducing the nitrogen rate (RNR) of application on rice yield and nitrogen use efficiency under side deep placement of nitrogen in paddy fields. Therefore, a field experiment of RNT and RNR treatments was conducted with nine fertilization modes during the 2018–2019 rice growing seasons in a rice–wheat cropping system of the lower reaches of the Yangtze River, China. Rice yield and nitrogen use efficiency were investigated under side deep placement of nitrogen. We found that under the same nitrogen application rate, the yield of RTN3 increased by 9.64 and 10.18% in rice varieties NJ9108 and NJ5718, respectively, compared with the farmers’ fertilizer practices (FFP). The nitrogen accumulation of RTN3 was the highest at heading stage, at 11.30 t ha−1 across 2018 and 2019. Under the same nitrogen application rate, the N agronomic use efficiency (NAE), N physiological efficiency (NPE) and N recovery efficiency (NRE) of RTN3 were 8.1–21.28%, 8.51–41.76% and 0.28–14.52% higher than those of the other fertilization modes, respectively. RNR led to decreases in SPAD value, leaf area index (LAI), dry matter accumulation, nitrogen accumulation, and nitrogen use efficiency. These results suggest that RTN3 increased rice yield and nitrogen use efficiency under the side deep placement of nitrogen, and RNR1 could achieve the goals of saving cost and increasing resource use efficiency. Two fertilization modes RTN3 and RNR1 both could achieve the dual goals of increasing grain yield and resource use efficiency and thus are worth further application and investigation.

Peptide stapling chemistry represents an attractive strategy to promote the clinical translation of protein epitope mimetics, but its use has not been applied to natural cytotoxic peptides (NCPs) to produce new oncolytic peptides. Based on a wasp venom peptide, a series of stapled anoplin peptides (StAnos) were prepared. The optimized stapled Ano-3/3s were shown to be protease-resistant and exerted superior tumor cell-selective cytotoxicity by rapid membrane disruption. In addition, Ano-3/3s induced tumor ablation in mice through the direct oncolytic effect and subsequent stimulation of immunogenic cell death. This synergistic oncolytic-immunotherapy effect is more remarkable on melanoma than on triple-negative breast cancer in vivo. The efficacies exerted by Ano-3/3s on melanoma were further characterized by CD8+ T cell infiltration, and the addition of anti-CD8 antibodies diminished the long-term antitumor effects. In summary, these results support stapled peptide chemistry as an advantageous method to enhance the NCP potency for oncolytic therapy.

Catalysts are needed for electrochemical and photochemical reduction of CO2 into valuable chemicals. Diamond and its related materials have been regarded as a promising class of catalysts for CO2 reduction. With varied forms, structures, dopants, sp2/sp3 ratios, surface functionalities, and the combination with different co-catalysts, a great diversity of diamond-based catalysts have been fabricated for CO2 reduction. This review summarizes state-of-art progress and achievements on the electrochemical CO2 reduction using different diamond and related electrodes, along with the selection of electrolytes and applied conditions. The applications of diamond nanoparticles and diamond related films for photochemical CO2 reduction are highlighted. The advanced strategies to further improve the catalytic activity of diamond towards CO2 reduction have been discussed and outlined.

The efficient electrocatalytic degradation of environmental pollutants requires an electrode with a large surface area, high electrocatalytic activities, long-term stability, and a low cost. Herein, the diamond fibers (DFs) are synthesized by overgrowing the cost-effective carbon fibers as the core with a uniform boron dopped diamond (BDD) film as a shell. Since these fibrous core/shell-like DFs combine both features of BDD and carbon fiber, they are utilized as the electrode for the efficient electrocatalytic degradation of environmental pollutants. The DFs exhibit a 5.2-fold larger surface area and a 6.8-fold higher peak current density than those of a planar BDD electrode. Methyl orange is degraded below the limit of detection within 1.5 h using these DFs, while the degradation fraction using a planar BDD electrode is only 22%. For other various organic pollutants, these DFs exhibit excellent degradation capacity. Such a high performance of electrocatalytic degradation of these environmental pollutants originates from increased surface areas and active sites by the three-dimensional fibrous structure as well as the decreased charge-transfer resistance by the core/shell structure. These DFs are thus promising as a new electrode material or an electrocatalyst for various catalytic applications in the environmental and energy fields.

In this study, we reported the in-situ fabrication of a series of Fe2O3/TiO2 monolithic catalysts on flexible Ti mesh via plasma electrolytic oxidation process, hydrothermal reaction and chemical bath deposition (CBD) method. The morphology tailoring of Fe2O3 nanostructures finds that Fe2O3 nanosheets supported on TiO2 exhibit superior catalytic performance with a complete oxidation of CO at 260 °C. The catalytic stability test indicates that the in-situ grown Fe2O3/TiO2 catalysts own outstanding performance for continuous CO oxidation due to the strong substrate adhesion without mass loss. The microstructures and interfaces of Fe2O3/TiO2 catalysts are well studied using series of characterization techniques. The in-situ preparation strategy of metal oxide catalysts in this work will open up more opportunities for the rational design of variety of monolithic catalysts used for CO oxidation, de-NOx, three-way catalysis and other related application in industry.

Three different agitator geometries for a dry stirred media mill with a horizontal drum were studied experimentally and by DEM (discrete element method) simulation. Two optimized models, model A with stirring arms oriented in the same direction and model B with inclined stirring arms, achieved more rapid grinding with the lower adhesion of particles to the mill than the conventional stirring arms. Model A achieved the finest grinding with sharpest particle distribution. DEM simulation results suggested that rapid mixing, large collision energy, and a large number of collisions result in rapid grinding. DEM simulations of model A confirmed that the particle collision energy in this model was the highest of the models tested and resulted in the largest energy consumption and the largest temperature increase. In model B, DEM simulation results suggested that collision energy increased locally at the wall and resulted in a local temperature increase at the shaft. The high number of collisions in model B also resulted in rapid grinding but with a broad particle distribution. The decrease of the particle adhesion in models A and B was caused by a decrease in the collision energy between particles and the wall in the normal direction.

Yellowhorn (Xanthoceras sorbifolium Bunge) is a woody oil species that is widely distributed in northwestern China. To investigate the molecular mechanisms underlying the drought and heat tolerance response of yellowhorn seedlings, changes in protein abundance were analyzed via comparative proteomics. Drought and heat treatment of seedlings was applied in growth chamber, and the leaves were harvested after 7 days of treatment. The total protein was extracted, and comparative proteomic analysis was performed via isobaric tag for relative and absolute quantitation (iTRAQ). The abundance of most of the proteins associated with oxidative phosphorylation, NADH dehydrogenase and superoxide dismutase (SOD) was reduced. The differential proteins associated with photosynthesis enzymes indicated that stress had different effects on photosystem I (PSI) and photosystem II (PSII). After comprehensively analyzing the results, we speculated that drought and heat stress could hinder the synthesis of riboflavin, reducing NADH dehydrogenase content, which might further have an impact on energy utilization. Yellowhorn seedlings relied on Fe-Mn SOD enzymes rather than Cu/Zn SOD enzymes to remove reactive oxygen species (ROS). In addition, heat-shock proteins (HSPs) had significant increase and played a key role in stress response, which could be divided into two categories according to their transcription and translation efficiency. Over all, the results can provide a basis for understanding the molecular mechanism underlying resistance to drought and heat stress in yellowhorn and for subsequent research of posttranslational modification-related omics of key proteins.

Plastic films have become an integral part of fruit and vegetable production systems, but their release of phthalate acid esters (PAEs) is a threat to human health. The release kinetics of PAEs and measures of risk are still not well understood. We investigated 50 agricultural films, with concentrations ranging from 2.59 to 282,000 mg kg-1. The seven commercially available film types included were polyvinylchloride (PVC), metallocene polyethylene (mPE), ethylene vinyl acetate (EVA), polyolefin (PO), and three mulch films. Bis(2-ethylhexyl) phthalate (DEHP) was detected in most of films, and its release fitted well into the first-order kinetic model. The release rate of DEHP was negatively related to the film thickness. The potential carcinogenic risks of DEHP in the air of six kinds of plastic greenhouses to human health were estimated. We found that the carcinogenic risks associated with PVC and mPE greenhouse films warrant greater attention. Though EVA, PO greenhouse, and mulch films were lower risk, we advise keeping plastic greenhouses well ventilated during the first month of use to reduce direct human exposure to volatile PAEs.

The genetic diversity and mating status of seed production stands are crucial factors impacting the genetic quality and ecological stability of progeny plantations. The genetic homogeneity of seeds collected from a seed production population in different years has not yet been clearly described. In this study, the genetic diversity and differentiation of a seed-tree stand of 58-year-old Pinus massoniana (P1959) and four-open pollinated plantations of its progeny (OS1996, OS2000, OS2006 and OS2015) were determined by using microsatellite markers. The results showed that similar high genetic diversity was preserved in the seed-tree stand and its four progenies. This implied that current artificial seed harvesting from the seed-tree stand for reforestation does not lead to a significant reduction in genetic diversity; the F index across most loci was significantly greater than zero, indicating population homozygote excess. The pairwise genetic differentiation of the five populations ranged from 0.035 to 0.075, among which OS2015 was the most differentiated from the parent. The differentiation between the parental population and its progeny seemed to increase with increasing age of the seed-trees. This implied that a limited pollination coupled with variable within-stand pollen availability has created opportunities for both self- and foreign pollination to be successful in various periods, resulting in a seemingly paradoxical scenario of both high selfing and gene flow, ultimately resulting in gradually increasing differences in the gene frequency composition between the parental population and its progeny. Management considerations in addressing these problems in similar seed production stands were discussed.

This work aims to explore the influence of freeze-thaw cycles and high temperature exposure on immobilization performance of geopolymer-zeolite A composites (GZAC) for strontium radionuclide. After 45 freeze-thaw cycles, no visible change in the phase composition, microscopic morphology and cumulative leaching fractions (CLF) of the Sr2+ ions could be observed. Although the zeolite phases in GZAC were completely destroyed at 800 °C, the CLF of Sr2+ ions from the GZAC still meet Chinese National Standard (GB14569.1-2011). At 1000 °C, the CLF of Sr2+ ions decrease distinctly, attributing to the further viscous sintering and obvious reduction in open porosity. Therefore, we could conclude that GZAC presents remarkable thermal stability for radioactive strontium immobilization.

Strontium phosphosilicate is one of the fastest-growing apatite in bone regeneration application due to the presence of strontium and silica components in the parent materials. However, bacterial infections cause setbacks to the bone regeneration process often leading to surgical revisions, and is a big issue that needs to be addressed. Silver on this front has proven to be a great substituent as seen in the case of calcium phosphate–based ceramics that addresses the bactericidal properties of a biomaterial. Apatite strontium phosphosilicate substituted with a stoichiometric amount of silver as a dopant was synthesized using a high-temperature solid-state reaction. The phase formation was characterized by XRD and FT-IR coupled with morphological features visualized using Electron Microscopy. Antibacterial properties were investigated quantitatively using Colony-forming unit method against both Gram-positive as well as Gram-negative bacteria. Cytotoxicity assay was performed against MG-63 Cell lines and it showed excellent biocompatibility at 25ug/ml with optimal doping of 2% silver. Further, apatite seeding and formation were characterized after immersion in simulated body fluid solution which showed apatite phase formation initiated after 4 days of treatment characterized by XRD and FT-IR studies. This apatite formation was also visualized and confirmed using SEM.

Shockwave/turbulent boundary layer interaction on flat plate are investigated by using direct numerical simulation at different wall temperature of T w / T r = 0.5 , 1.0 , 2.0 respectively. Responses of skin friction, velocity profile and root mean square velocity profile are examined. Analysis on velocity profiles indicate that streamwise velocity in the outer part of boundary layer experiences a reduction with wall temperature going up. Skin friction decreases while wall is heating mainly caused by a lower velocity gradient near the wall at a high temperature. A lower skin friction on high wall temperature results in a stronger separation. The comparison of root mean square velocity profile shows turbulent kinetic energy is augmented on a heating wall. The maximum value moves closer to the wall with wall temperature increasing. The scale of separation bubble is amplified with wall temperature increasing. Near-wall streaks become unstable and get an increment in spanwise distance. The process of near-wall strip vortices evolving to complicated 3-dimonsional structures is accelerated and amplified in a high wall temperature. Counter-rotating vortex in reattachment process is evaluated in the three cases. The scale of such vortex gets larger when wall temperature gets higher. The spanwise distance between counter-rotating vortices rises obviously and break down to smaller coherent structures quicker.

Orbital perturbations caused by the space environment will induce deviations compared with the prescribed motion trajectory or dynamic performance of the tethered satellite system (TSS). To comprehensively investigate the effects of the orbital perturbations on the TSS, a precise variable-length element that can describe the large deformation and flexibility of the tether is adopted in this paper to predict the deployment dynamics considering orbital perturbations, including atmospheric drag, solar pressure, lunisolar gravitation, and $J_{2}$ perturbation. To this end, the variable-length element using arbitrary Lagrangian-Eulerian (ALE) description in the frame work of absolute nodal coordinate formulation (ANCF) is developed firstly. Subsequently, the dynamic governing equations for the TSS are established in the context of ANCF with the employment of ANCF reference node (ANCF-RN). Effects of orbital perturbations including atmospheric drag, solar pressure, lunisolar gravity and $J_{2}$ perturbation on the dynamics of an optimal deployment are analyzed numerically. It is shown that the orbital perturbations except the $J_{2}$ perturbation will induce the out-of-plane motion of the TSS. Additionally, the tether tension is less affected by the orbital perturbations. By contrast, the lunisolar gravitation will induce a deviation on the motion path of satellite, which should be considered in the design phase of the TSS.

In this paper, we study the global dynamics of a density-dependent predator-prey system with ratio-dependent functional response. The main features and challenges are that the origin of this model is a degenerate equilibrium of higher order and there are multiple positive equilibria. Firstly, local qualitative behavior of the system around the origin is explicitly described. Then, based on the dynamics around the origin and other equilibria, global qualitative analysis of the model is carried out. Finally, the existence of Bogdanov-Takens bifurcation (cusp case) of codimension two is analyzed. This shows that the system undergoes various bifurcation phenomena, including saddle-node bifurcation, Hopf bifurcation, and homoclinic bifurcation along with different topological sectors near the degenerate origin. Numerical simulations are presented to illustrate the theoretical results.

Cis (Z)-β-carotenes with 25.3% 9Z-β-carotene were prepared for nanostructured lipid carriers (NLCs). The optimal conditions for NLC preparation using an orthogonal experimental method were as follows: the total lipid concentration was 9% (w/v), the surfactant concentration was 1.4% (w/v), the solid to liquid lipid ratio was 3:1 (w/w), and the homogenization pressure was set at 500 bar for three cycles. Under these conditions, the encapsulation efficiency (%) of the NLC was 95.64%, and the total β-carotene in NLCs was 2.9 mg/mL, which was significantly higher than those reported by others. The proportion of total Z-β-carotenes was as high as 53.3%, the particle size was 191 ± 6.46 nm, and the polydispersity index was 0.2 ± 0.03. Storage stability results indicated that the β-carotene-loaded NLC stabilizes both 9Z-β-carotene and total β-carotene from leakage and degradation during 21 days of storage at pH 3.5-7.5 at low temperatures (4 °C), especially for the more bioactive 9Z-β-carotene. The technique with an improved ratio of 9Z-β-carotene, loading capacity, water solubility, and bioaccessibility of the β-carotene NLC provides an effective strategy for β-carotene applications in functional foods or beverages and in nutraceutical preparations.

Based upon the fact that a constant long-term mean could not provide a good description of the term structure of the implied volatility and variance swap curve, as suggested by Byelkina and Levin (in: Sixth world congress of the Bachelier Finance Society, Toronto, 2010) and Forde and Jacquier (Appl Math Finance 17(3):241–259, 2010), this paper presents a new stochastic volatility model, by assuming the long-term mean of the volatility in the Heston model be stochastic. An important feature of our model is that it still preserves the essential advantage of the Heston model, i.e., the analytic tractability, because a closed-form pricing formula for European options can be derived, which could not only facilitate the risk management process but also help save plenty of time in terms of model calibration. The effect of the newly introduced stochastic long-term mean is demonstrated through the numerical comparison with the Heston model. It is also shown that the current model can overall lead to more accurate option prices than the Heston model, through a carefully designed empirical study.

The method for precisely determining the astronomical azimuth using the local hour angle (LHA) of Polaris is only applicable in northern middle latitudes. In addition, the meridian star pair method is limited by the conditions of star selection and matching. A new hour angle method for multiple meridian stars is proposed, which is suitable for any part of the global region. When multiple south and north stars have been observed, the influence of longitude error and timing error on the azimuth is modified by linear regression. A precise astronomical position is not required, and there is no limit to the specific position of the meridian stars. Therefore, both the number of observable stars and work efficiency are greatly increased. Our experiment indicates that the results of the new method can reach the first-order accuracy level; i.e., the root mean square error (RMSE) is less than 0.5 ″ , even when the amount of observed data is reduced to half that of the Polaris method.

Crude ferronickel alloy can be produced by the carbothermal reduction of laterite ore-coal composite. The size of ferronickel particles in semi-molten state is crucial for the subsequent magnetic separation between the ferronickel and slag. Aimed to better understand the effects of reducing parameters on the size of ferronickel particles in the reduced laterite nickel ores, a series of carbothermal reduction experiments of laterite ore-coal composite in tall pellets bed was carried out. The experimental results indicated that, higher reducing temperature, longer reducing time and more CaO additive were beneficial for the aggregation and growth of ferronickel particles. Temperature (1400 °C) is the most important parameter. Less CaO additive needs longer reducing time, more CaO additive needs shorter reducing time. Excessive CaO amount (CaO = 10 pct) may prevent ferronickel particles from aggregation and growth due to its rapid melting. The importance ranking of these parameters should be temperature > time > CaO additive. The optimum reduction parameters were “1400 °C, 45 minutes, CaO = 0 pct” and “1400 °C, 30 minutes, CaO = 5 pct”. Under these conditions, all the ferronickel particles in 4 layers were clear and bigger. The percentages of + 50 μm of particles were about 65 and 59 pct respectively, and the recovery rates of Ni were about 88 and 85 pct. The findings from this work may provide guidelines for the improvement of ferronickel alloy production by laterite nickel ores.

We report on the development of green and white OLEDs with high efficiency based on Bis(4-(9,9-dimethylacridin-10(9H)-yl) phenyl)methanone (DMAC-BP) manufactured by a facile vacuum evaporation technique via device interfaces engineering. Single, double, and three organic layer undoped OLEDs based on DMAC-BP have been fabricated. Among the developed green devices, the performance of three-layer structured OLEDs is the optimum when mCP (1,3-Bis(carbazol-9-yl)benzene) works as the hole transport layer (HTL) and electron block layer (EBL). The measured maximum external quantum efficiency (EQE), current efficiency (CE), power efficiency (PE), and luminance are 8.1%, 25.9 cd/A, 20.3 lm/W, and 42,230 cd/m2, respectively. Importantly, the OLEDs retain the most of their performance at 1000 cd/m2, and the EQE, CE, and PE are 7.2%, 23.7 cd/A, and 19.1 lm/W, respectively. The achieved high efficiency is attributed to the bipolar transport characteristics of DMAC-BP and the matched bandgap between HTL and emission layer (EML). In addition, WOLEDs with DMAC-BP as green layer are all warm white devices. Among them, the structure of green-red-blue (device W3) demonstrates the best performance with a maximum EQE and brightness of 4.4% and 7525 cd/m2. Our findings will facilitate the great potential applications of undoped TADF emitters, and establish a good foundation for the preparation of high-efficiency and low-cost commercial OLEDs.

Summary Li-ion battery safety issues related to fires and explosions are frequently triggered by Li dendrite growth, which is a predominant reason for separator piercing and cell shorts and is very difficult to detect in the early state. Here, we developed a sensitive detection method based on H2 gas capture that could detect trace amounts of Li dendrite formation. H2 gas was generated due to reaction of metallic Li with polymer binders. Even micron-scale Li dendrite (∼2.8 × 10−4 mg and 50 μm) growth can trigger H2 capture. Overcharge experiment with a LiFePO4-graphite battery pack (8.8 kWh) shows that H2 was captured first among H2, CO, CO2, HCL, HF, and SO2, and the capture time was 639 s earlier than smoke and 769 s earlier than fire. The Li dendrite growth can be completely prevented once H2 is captured, with neither smoke nor fire observed, which provides an effective method for early safety warning.

Microbial contamination in water remains a global issue in threatening human health. Although current disinfection methods can effectively control microbial contamination, the formation of harmful disinfection byproducts is increasingly questioned. Towards this goal, a facile, green and low-priced bacteriocide - magnetic biochar/quaternary phosphonium salt (MBQ) - was developed using precipitation of iron oxide on biochar followed by ion exchange with quaternary phosphonium salt (QPS). Gram-negative bacteria Escherichia coli and Gram-positive bacteria Staphylococcus aureus - were used as model pathogens to quantify the antibacterial activity and to elucidate the antibacterial mechanism. MBQ was an effective antimicrobial agent against both pathogenic bacteria. The controllable release of QPS and magnetic recovery of MBQ favored antibacterial reuse. Significant disruption of membrane led to the inactivation of bacteria, resulting from the loss of cell membrane integrity and permeability. The induced oxidative damage inhibited the essential cell metabolism. Penetration of MBQ nanoparticles through the cell wall and membrane into the cytoplasm enhanced the biocide effect. Taken together, MBQ, presenting effective, recyclable and long-acting antibacterial properties, has a promising application in bacterial decontamination.

In quantitative finance practice, model calibration is a key challenge. This is especially so when a local regime-switching model needs to be calibrated because designing an efficient and reliable algorithm to obtain local volatility values as a function of underlying price and time is important for the model to be successfully used in practice. Therefore, this paper proposes a new algorithm for calibrating local regime-switching models with observed option prices available for a particular market that is suitable for this type of model. The newly proposed algorithm is tested with calibrations performed on synthetic as well as real market data. Our empirical test results indicate that the algorithm has great potential to be used in financial risk management.

The effect of the surface wettability of plasma-modified vertical Si nanowire array on the bio-fouling performance has been investigated. The Si nanowires prepared by a metal-assisted chemical etching technique exhibit a super-hydrophilic surface. The treatment in CH4/H2 gas plasma environment leads to the decoration of graphite and diamond nanoparticles around Si nanowires. The detailed interface between graphite/diamond and Si nanowire was characterized by HRTEM technique. These surface-modified nanowire samples show an increased water contact angle with ultrananocrystalline diamond decorated ones being superhydrophobic. The immersion test in chlorella solution reveals that the diamond-coated Si nanowires possess the least attachment of chlorella in comparison with other Si nanowires. This result confirms that the coating of Si nanowires with diamond nanoparticles shows the best behavior in anti-biofouling. Importantly, this work provides a method fabricated super-hydrophobic surface for the application of biofouling prevention.

Thanks to the rapid development of CNNs and depth sensors, great progress has been made in 3D hand pose estimation. Nevertheless, it is still far from being solved for its cluttered circumstance and severe self-occlusion of hand. In this paper, we propose a method that takes advantage of human hand morphological topology (HMT) structure to improve the pose estimation performance. The main contributions of our work can be listed as below. Firstly, in order to extract more powerful features, we concatenate original and last layer of initial feature extraction module to preserve hand information better. Next, regression module inspired from hand morphological topology is proposed. In this submodule, we design a tree-like network structure according to hand joints distribution to make use of high order dependency of hand joints. Lastly, we conducted sufficient ablation experiments to verify our proposed method on each dataset. Experimental results on three popular hand pose dataset show superior performance of our method compared with the state-of-the-art methods. On ICVL and NYU dataset, our method outperforms great improvement over 2D state-of-the-art methods. On MSRA dataset, our method achieves comparable accuracy with the state-of-the-art methods. To summarize, our method is the most efficient method which can run at 220.7 fps on a single GPU compared with approximate accurate methods at present.

Surface plasmon polariton (SPP) Airy beams are very attractive in theory and applications. We propose a new method to design dielectric relief holographical structures for controlling the SPP wave propagations and generating SPP Airy beams on metal surface. In the dielectric relief holography (DRH) method, both phase and amplitude are considered. The thickness of designed dielelctric films is proportional to the intensity of SPPs interference in holography. The films designed by the DRH method are coated on metal surface and can control SPPs propagation effectively. The complicated Airy beams can also be generated through the films designed by the method. The finite difference time domain (FDTD) method is used to test the functionalities of the designed structures and find the optimal parameters. The structures designed by the DRH method can be manufactured with traditional die or corroding methods. The investigation on the method extends SPP device manufacture methods, and therefore may open up the possibility for mass industrial manufacture of plasmonic devices.

Chiral allenes are important structural scaffolds found in many natural products and drugs, and in addition, they also serve as building blocks for many organic transformations. The conventional methods for preparing chiral allenes rely on the resolution of racemic allenes and the chirality transfer between non-racemic propargylic derivatives and nucleophilic reagents. In recent years, the synthesis of chiral allenes by asymmetric catalysis has been achieved fruitful results. Among them, enantioselective synthesis of chiral allenes with chiral organic catalysts is particularly prominent. In this paper, the research progress of enantioselective synthesis of chiral allenes catalyzed by chiral organic catalysts in recent years is reviewed, including various reaction systems and synthesis applications.

In this article, two kinds of dual-layer segmented Halbach arrays have been proposed for permanent-magnet (PM) brushless machines. The analytical expressions of magnetic fields due to the inner-/outer-layer Halbach magnets have been separately obtained. For the maximal flux density in the air gap, the optimal magnet segment radian ratios or magnetization angles for each dual-layer Halbach array have been analytically determined separately. The induced back electromotive force and electromagnetic torque have been analytically obtained. The prediction results show that the optimized electromagnetic performances for each double-layer segmented Halbach array with different slot and pole combinations are better than those for the corresponding single-layer one. The proposed analytical model can also be applied for optimizing the multi-layer segmented Halbach array. The analytical prediction results of a PM machine with the double-layer segmented Halbach array have been compared with those obtained by a finite-element method.

Nontargeted analysis of food safety requires selective removal of interference matrices and highly efficient recovery of chemical hazards. Porous materials such as covalent organic frameworks (COFs) show great promise in selective adsorption of matrix molecules

For the past three decades, the coordination-driven self-assembly of three-dimensional structures has undergone rapid progress; however, parallel efforts to create large discrete two-dimensional architectures—as opposed to polymers—have met with limited success. The synthesis of metallo-supramolecular systems with well-defined shapes and sizes in the range of 10–100 nm remains challenging. Here we report the construction of a series of giant supramolecular hexagonal grids, with diameters on the order of 20 nm and molecular weights greater than 65 kDa, through a combination of intra- and intermolecular metal-mediated self-assembly steps. The hexagonal intermediates and the resulting self-assembled grid architectures were imaged at submolecular resolution by scanning tunnelling microscopy. Characterization (including by scanning tunnelling spectroscopy) enabled the unambiguous atomic-scale determination of fourteen hexagonal grid isomers. Metal-mediated self-assembly in solution typically leads to small two- and three-dimensional architectures on scales smaller than 10 nm, but now a series of large, discrete, two-dimensional supramolecular hexagonal grids have been prepared through a combination of intra- and intermolecular coordination interactions. These 20-nm-wide grids have been imaged at submolecular resolution using scanning tunnelling microscopy.

In recent years, more and more high Al2O3 iron ores were used in East Asia, especially in China, which increased the Al2O3 content in blast furnace (BF) slag and resulted in poor metallurgical properties of slag. Adding MgO-bearing flux is one of the methods to improve the metallurgical properties of slag with high Al2O3. However, there is lack of theoretical basis for the proper MgO/Al2O3 ratio. Therefore, the properties of slag in SiO2–CaO–MgO–Al2O3 system were investigated based on viscosity experiments and phase diagram analyses at 1500 °C, and the proper MgO/Al2O3 ratio was explored according to the Al2O3 content in slag. The experimental results show that: (1) in the case of Al2O3 content less than 14 mass%, there is no limitation of the MgO/Al2O3 ratio, and the amount of MgO in slag can be determined according to the hearth temperature and desulfurization; (2) in the case of Al2O3 content between 15 and 17 mass%, the proper MgO/Al2O3 ratio should be 0.40–0.50; (3) in the case of Al2O3 content between 18 and 20 mass%, the proper MgO/Al2O3 ratio should be 0.45–0.55. Consequently, the three-segment control theory of MgO/Al2O3 for BF slag was built, and the actual BF performances proved the validity and applicability of this theory. The research contents and results can give theoretical guidelines for stable BF operation in a wide range of Al2O3 content of 12–20 mass%.

Effects of a low-temperature solution heat treatment (SHT) below γ′ solvus temperature and a high-temperature partial solution heat treatment (SHT) above γ′ solvus temperature on microstructural evolution and stress rupture properties of a directionally solidified nickel-based superalloy during long-term thermal exposure at 900 °C were investigated in detail. The two heat treatments generated different microstructures, e.g., different γ′ sizes and surface fractions of residual γ–γ′ eutectic phase. Carbides in the two heat-treated samples exhibited different microstructural stability during the subsequent long-term thermal exposure. The creep lifetime at 870 °C/310 MPa of the samples treated by the high-temperature SHT is more than two times of that treated by the low-temperature SHT, whereas the creep lifetime of the samples treated by the high-temperature partial SHT exhibited a sharp reduction after 1000-h exposure and then decreased by a steady rate up to 10,000-h exposure. In comparison, the creep lifetime of the samples treated by the low-temperature SHT exhibits a slower reduction rate from 0- up to 10,000-h exposure.

Cubic silicon carbide (3C‐SiC) material feature a suitable bandgap and high resistance to photocorrosion. Thus, it has been emerged as a promising semiconductor for hydrogen evolution. Here, the relationship between the photoelectrochemical properties and the microstructures of different SiC materials is demonstrated. For visible‐light‐derived water splitting to hydrogen production, nanocrystalline, microcrystalline and epitaxial (001) 3C‐SiC films are applied as the photocathodes. The epitaxial 3C‐SiC film presents the highest photoelectrochemical activity for hydrogen evolution, because of its perfect (001) orientation, high phase purity, low resistance, and negative conduction band energy level. This finding offers a strategy to design SiC‐based photocathodes with superior photoelectrochemical performances., Thin films: For visible‐light‐derived water splitting to hydrogen production, nanocrystalline, microcrystalline and epitaxial (001) 3C‐SiC films are applied as photocathodes. The epitaxial 3C‐SiC film presents the highest photoelectrochemical activity for hydrogen evolution, because of its perfect (001) orientation, high phase purity, low resistance, and negative conduction band energy level.

The correlation between the choice of reference material and model utilized in determining fracture toughness from indentation-induced radial cracks was critically investigated with six commonly used reference materials. Initially, the empirical constants in Anstis’s and Laugier’s equations were calculated, compared and analyzed. According to the values of the constants, the reference materials were categorized into three groups. This classification was further verified by evaluating the corresponding constants of 13 additional equations. To account for the classification, FIB technique was employed to examine the crack morphology in the reference materials – Si (100) features an almost Half-penny-shaped crack while the cracks in SiC (0001) display nearly as a rectangle, both far from the assumptions employed by the models. Subsequently, an improved and more reliable procedure to determine fracture toughness is proposed. Finally, with this procedure, the fracture toughness of a diamond/SiC composite film is determined to be 11.1 ± 1.1 MPa m1/2.

The Tancheng–Lujiang (Tanlu) fault zone is the most active fault zone in eastern China. In this zone, the Anqiu–Juxian fault represents the most recently active fault and has the clearest surface traces and the highest seismic risk. This study comprehensively analyzes the kinematic characteristics of the Jiangsu segment of the Anqiu–Juxian fault using field geological surveys, trenches, shallow seismic reflection surveys, combined borehole section exploration, and middepth seismic reflection surveys. The results show that the Jiangsu segment of the Anqiu–Juxian fault features a single branch in the bedrock outcrop area, with reverse strike-slip motion near North Maling Mountain and Chonggang Mountain and normal strike-slip motion near South Maling Mountain. The sedimentary zone features two normal strike-slip faults (east and western branches), which represent the synsedimentary boundaries of a half-graben rift basin. The kinematic process is represented by rotational movement along the strike-slip fault with a curved path. The resulting tensile and compressive stresses are accommodated by dip-slip movement at both ends of the strike-slip fault. The activity of the Jiangsu segment of the Anqiu-Juxian fault can be divided into two periods. The first period of activity occurred before the later part of the Late Pleistocene, when movement along this curved segment occurred, forming the western branch of the Xinyi segment and the eastern branch of the Suqian segment. The second period of activity started in the later part of the Late Pleistocene and continues today. It is characterized by activity on the western branch of the Xinyi segment and the western branch of the Suqian segment of the Jiangsu segment, while the eastern branch of the Xinyi segment and the eastern branch of the Suqian segment became inactive and can be considered Late Pleistocene faults. The maximum vertical slip rate of the Jiangsu segment of the Anqiu–Juxian fault since the Pleistocene has been 0.28 mm/a. The Jiangsu segment of the Anqiu–Juxian fault formed via dextral strike-slip faulting, mainly due to the southward movement of the region to the east of the fault.

Background: Currently, limited tumor drug permeation, poor oxygen perfusion and immunosuppressive microenvironments are the most important bottlenecks that significantly reduce the efficacy of photodynamic therapy (PDT). The main cause of these major bottlenecks is the platelet activation maintained abnormal tumor vessel barriers. Thus, platelet inhibition may present a new way to most effectively enhance the efficacy of PDT. However, to the best of our knowledge, few studies have validated the effectiveness of such a way in enhancing the efficacy of PDT both in vivo and in vitro. In this study, perfluoro-N-(4-methylcyclohexyl) piperidine-loaded albumin (PMP@Alb) nanoparticles were discovered, which possess excellent platelet inhibition ability. After PMP@Alb treatment, remarkably enhanced intra-tumoral drug accumulation, oxygen perfusion and T cell infiltration could be observed owing to the disrupted tumor vessel barriers. Besides, the effect of ICG@Lip mediated PDT was significantly amplified by PMP@Alb nanoparticles. It was demonstrated that PMP@Alb could be used as a useful tool to improve the efficacy of existing PDT by disrupting tumor vessel barriers through effective platelet inhibition.

The integration of sp2-/sp3-bonded carbon has aroused increasing attention on attaining a great electron field emission (EFE) performance. Herein, a novel hierarchical diamond@carbon nanowalls/diam...

This study examined the influence of biochar addition on fungal community during composting of cow manure using high-throughput sequencing. Two treatments were set up, including compost of cow manure plus 10% biochar (BC) and cow manure compost without biochar (CK). Fungal community composition varied obviously during composting in both treatments, and main fungi included Aspergillus, Myriococcum, Thermomyces, Mycothermus, Scedosporium, Cladosporium, and unclassified Microascaceae. Fungal community composition was altered by biochar during composting, especially during the thermophilic and the cooling phase, promoting Aspergillus and Myriococcum while inhibiting unclassified Microascaceae and Thermomyces. Based on linear discriminant analysis effect size analysis, common indicator groups were detected in both composts; however, specific indicator groups were also found in BC treatment, including Clavicipitaceae, Tremellales, Gibberella, and Coprinopsis. Canonical correspondence analysis (CCA) indicated that moisture content, organic matter, C/N, and pH had significant correlation (p 0.05) with fungal composition in both treatments. However, in compost added with biochar, temperature was not an important factor affecting fungal community (p 0.05).

Silicon vacancy (SiV) centers in CVD-deposited nanodiamond particles or films always exhibit a photoluminescent (PL)-quenching behavior. Herein, in order to overcome this issue, air annealing of nanocrystalline diamond (NCD) films with uniform doping of Si atoms is employed to improve the PL emission efficiency of SiV centers. Without severe mass loss in diamond, SiV centers exhibit an increased PL emission intensity at 738 nm with an increased annealing temperature and time. In comparison to the untreated film, the maximum PL enhancement reaches about 200 and 1473 folds when the NCD films are annealed at 600 °C for 60 min and 700 °C for 20 min, respectively. Such giant increase in SiV PL emission is mainly attributed to the transition of diamond surface from hydrogen to oxygen termination together with the optimized crystalline quality of the annealed films, as confirmed by the HRTEM, Raman and XPS measurements. A schematic model based on the theory of surface band bending is proposed to elucidate the mechanism of the SiV PL enhancement in oxygen-terminated NCD films: a near-surface light trap layer formed in hydrogen-terminated NCD is converted during the oxidation process, leading to the additional collection of SiV PL emission from the inner layer.

In logistics warehouse sorting, rubbish classification, and household services, scenarios exist in which rigid and soft objects are randomly piled together. In such situations, two major challenges arise in robotic picking tasks: the first is to distinguish rigid objects from soft objects, and the second is to grasp one object of each type at a time. In this study, we propose a novel robotic picking methodology for the grasping of objects mixed with towels. The proposed approach is based on a novel object detection method that can identify a rigid object placed in different directions using a rotational bounding box. Rigid objects can be separated from the mixed scene without object segmentation. Moreover, the grasping pose of a rigid object can be generated directly along its principal axis, without using a CAD model or specific pose detection method. The gripper opening width is determined according to the object size. Therefore, our method can detect whether other objects, particularly soft ones, exist around a rigid object. If no suitable grasping pose is available for the rigid objects, the grasping pose on a wrinkle of the towel is selected. The experiments demonstrate that our method can accomplish the picking task in scenes with mixed rigid and soft objects, thereby indicating its significance in robotic object detection and sorting.

Summary Lithium-sulfur (Li-S) and Lithium-selenium (Li-Se) batteries are considered as promising candidates for next-generation battery technologies, as they have high energy density and low cost. However, due to the use of a solid Li-metal anode and a liquid organic electrolyte, the current Li-S and Li-Se batteries face several issues in terms of Coulombic efficiency and cycling stability, which seriously impeded their development. Here, we report solid-electrolyte-based liquid Li-S and Li-Se (SELL-S and SELL-Se in short) batteries. The batteries use a Li6.4La3Zr1.4Ta0.6O12 (LLZTO) ceramic tube as electrolyte and work at temperatures higher than the melting point of Li; thus, polysulfide or polyselenide shuttle effects and Li dendrite growth are effectively prevented, and high energy density, together with high stability, fast charge/discharge capability, high Coulombic efficiency, and high energy efficiency, can be achieved. The SELL-S and SELL-Se batteries provide broader platforms for constructing high-energy, high-power, long-lifetime, and low-cost energy storage.

On the basis of intensity modulation, a vibration sensor using a tapered photonic crystal fiber (PCF) is demonstrated. The fiber is a solid-core PCF with a central air hole embedded in the core region. The addition of the air-hole initiates the core/cladding intermodal coupling, and consequently, modulates the output light intensity when the fiber is under external disturbance. The sensing unit is configured by firstly tapering the PCF down to a waist of 72.6 μm, and then splicing its two ends to a single-mode fiber (SMF) and a multi-mode fiber (MMF), respectively. The sensor is then used for measuring a variety of vibrational signals, such as single frequency (in the range of 30~10000 Hz), dual-frequency vibrations, and vibration accelerations (with linear responses from 0.5 to 10 m/s2). In addition, the sensitivity, influenced by varying the length of the sensor head, is also investigated.