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We here investigated the effect of vanadium microalloying on the microstructure, mechanical properties, especially corrosion performances of low carbon bainitic steels. The corrosion behaviors of the steels with different vanadium contents in 3.5 wt% NaCl solution were evaluated by electrochemical tests (including polarization curves and electrochemical impedance spectroscopic measurements) and alternating immersion test (including weight loss and rust layer observation). Results show that the mechanical properties and corrosion resistance of low carbon bainitic steels can be synergistically improved with vanadium microalloying. With help of the electron backscatter diffraction characterization and scanning Kelvin probe force microscopy, we first discovered that although the number of micro-galvanic couples increases because of grain refinement, the Volta potential gradient between the matrix and grain boundaries are decreased with vanadium microalloying, which can promote the formation of compact protective rust layers and improve the corrosion resistance of vanadium micro-alloyed low carbon bainitic steels.

The relationships among sea ice melting, phytoplankton assemblages, and the production of climate‐relevant trace gases in the Southern Ocean are gaining increasing attention from the scientific community. This is particularly true for dimethyl sulfide (DMS), which plays an important role in atmospheric chemistry by influencing the formation of sulfated aerosols with radiative impacts and constituting cloud condensation nuclei. In the current study, chlorophyll a(Chl a), DMS and its precursors dimethylsulfoniopropionate (DMSP), were quantified in the Weddell–Scotia Confluence (WSC) during the 2018 record ice extent minimum period. Mixed layer changes were found to be generally associated with spatial variation in sea ice melt, with the depth being six times deeper in ice‐free, well‐mixed regions than in seasonal ice‐melting zones. The surface Chl aconcentration increased from ice‐free to ice‐melting regions with elevated sea ice meltwater percentages and drawdown surface nutrient concentrations. The concentrations of surface and depth‐integrated Chl ain the upper 150 m reached maxima in the ice‐melting region with the highest fraction of sea ice meltwater, illustrating that sea ice melting promoted the occurrence of phytoplankton blooms. The DMS and DMSP concentrations in the vicinity of the ice‐melting zone were approximately three times higher than those in the ice‐free waters. The observations of this study show that the regions of ice melting in the WSC were a zone of particularly high sea–air fluxes of DMS, which could significantly contribute to the atmospheric budget of DMS in the polar regions.

GaInSn liquid metal is demonstrated to be efficient for resolving the adsorption of polysulfides and subsequent catalytic conversion of Na2S in the metal sulfide anode for Na-ion batteries.

This letter proposes a novel multiple extended target (ET) joint tracking and classification (JTC) algorithm based on Gaussian processes (GPs) and labeled multi-Bernoulli (LMB) filter, called the ET-JTC-GP-LMB filter, which aims to track and classify simultaneously multiple ETs with the goal of improving estimation performance. Firstly, we construct the relationship between GP-based extension state and prior class information (PCI), and design a new class probability update method. Then, we integrate these two works into the GP-based ET LMB filtering framework, propose the ET-JTC-GP-LMB filter, and provide its gamma-Gaussian-Gaussian mixture implementation to form a closed recursion. Finally, we present an evaluation metric called class recognition rate (CRR) to evaluate classification performance. The simulation results demonstrate the superior performance of the proposed filter.

The inflow of warm and nutrient‐rich Pacific Water (PW) through the Bering Strait into the Arctic Ocean is likely to have far‐reaching consequences for the ecosystem and biogenic sulfur cycle in the Earth's sensitive subarctic–arctic region of the Pacific sector, even impacting climate change under global warming scenarios. We performed a detailed biogeochemical study of summer biogenic sulfur cycling from cold (2012) to warm (2014) years in the Bering Strait and the Chukchi Sea, so as to highlight the importance of enhanced Pacific inflow in driving dimethylsulfide (DMS) variability. In the Bering Strait, the enhanced Pacific inflow led to the vertical expansion of the eastern high‐DMS regions due to the vertical extension of Alaska Coastal Water, and the horizontal expansion of the western surface high‐DMS regions due to the westward intrusion of Bering Shelf Water. The enhanced extension of PW potentially stimulated seawater warming, the northward retreat of the ice edge, and the enlargement of sea ice‐free areas in the Chukchi Sea. The northern ice melting zone at 71°N with a bloom of phytoplankton was an area of locally high dimethylsulfoniopropionate concentrations and slow DMS consumption in 2012. A hotspot for dimethylated sulfur compound concentrations and DMS sea–air flux occurred in the convergence region near 67.7°N during 2014, due to enhanced mixing caused by increased Bering Sea Water. Owing to the increased advection of PW during 2012–2014, surface DMS and its emission to the atmosphere increased sharply by threefold in the Chukchi Sea.

Aims: To detect mutations in juvenile-onset open-angle glaucoma in a Chinese family and to describe the characteristic ophthalmic phenotypes of this pedigree. Methods: There were 14 individuals in this four-generation pedigree. All living members of the family underwent comprehensive ophthalmic examinations. Five patients presented with elevated intraocular pressures. All of them shared early-onset disease, with a mean onset age of 14.4 years and continuing aggressive damage to their optic nerves. Hyperpigmentation in the trabecular meshwork and sometimes-broad iris processes were noted in this family using gonioscopy. All exons of candidate genes (MYOC, OPTN, CYP1B1) were amplified using the polymerase chain reaction, and analysed with an ABI 3700XL Genetic Analyser. Results: A heterozygous missense mutation in exon 3 (c.733 T > G) of the MYOCgene was found in the five JOAG patients and one 7-year-old boy with no ophthalmic manifestation of glaucoma, but it was absent in other members of the family and in the controls. This mutation resulted in a transversion of cysteine to glycine (Cys245Gly). Conclusions: We concluded the novel MYOCc.733 T > G mutation found in a Chinese family with JOAG caused a severe type of JOAG exhibiting early onset, high IOP, and severe optic nerve damage. Interestingly, unlike other reported MYOC mutation families, our patients exhibited marked angle pigmentation and iris processes.

Both azido (N3) and trifluoromethyl (CF3) groups are key moieties of numerous valuable molecules that are extensively applied in drug discovery, chemical biology, and synthetic chemistry. However, the asymmetric construction of chiral quaternary stereocenters bearing both N3and CF3groups is still unexplored. Herein, we report a kind of bench-stable and easily adjustable benziodazolone-based azidating reagents. These reagents were used to achieve an enantioselective copper-catalyzed azidation of N-unprotected 3-trifluoromethylated oxindoles to provide diverse enantioenriched 3-N3-3-CF3oxindoles.

Abstract

Piezoelectrics interconvert mechanical energy and electric charge and are widely used in actuators and sensors. The best performing materials are ferroelectrics at a morphotropic phase boundary, where several phases coexist. Switching between these phases by electric field produces a large electromechanical response. In ferroelectric BiFeO3, strain can create a morphotropic-phase-boundary-like phase mixture and thus generate large electric-field-dependent strains. However, this enhanced response occurs at localized, randomly positioned regions of the film. Here, we use epitaxial strain and orientation engineering in tandem—anisotropic epitaxy—to craft a low-symmetry phase of BiFeO3that acts as a structural bridge between the rhombohedral-like and tetragonal-like polymorphs. Interferometric displacement sensor measurements reveal that this phase has an enhanced piezoelectric coefficient of ×2.4 compared with typical rhombohedral-like BiFeO3. Band-excitation frequency response measurements and first-principles calculations provide evidence that this phase undergoes a transition to the tetragonal-like polymorph under electric field, generating an enhanced piezoelectric response throughout the film and associated field-induced reversible strains. These results offer a route to engineer thin-film piezoelectrics with improved functionalities, with broader perspectives for other functional oxides.

ABSTRACTIncreasing evidences have confirmed that long non-coding RNA LOXL1-AS1 functions in multiple human diseases. Here, we aim to explore the function and mechanism of LOXL1-AS1 in modulating oxidized low-density lipoprotein (ox-LDL)-induced angiogenesis of endothelial cells (ECs). Presently, we found that LOXL1-AS1 and KLF6 were upregulated in ECs treated by Ox-LDL in a dose- and time-dependent manner while miR-590-5p was downregulated. Overexpression of LOXL1-AS1 aggravated Ox-LDL mediated ECs proliferation and migration, and promoted angiogenesis both in vitroand in vivo. On the contrary, enhancing miR-590-5p or inhibiting LOXL1-AS1 level led to suppressive effects on the proliferation, migration and angiogenesis of ECs. Moreover, LOXL1-AS1 upregulation promoted the expression of vascular endothelial growth factor (VEGF), MMPs (including MMP2, MMP9 and MMP14) and also activated VEGF/VEGFR2/PI3K/Akt/eNOS pathway. Mechanistically, LOXL1-AS1 works as a competitive endogenous RNA (ceRNA) by sponging miR-590-5p, which targeted at the 3ʹ-untranslated region (3ʹUTR) of KLF6. Additionally, the proliferation, migration and angiogenesis of ECs were elevated following KLF6 upregulation. By detecting the expression of LOXL1-AS1 and miR-590-5p in the serum of healthy donors and atherosclerosis patients, it was found that LOXL1-AS1 was upregulated in atherosclerosis patients (compared with healthy donors) and had a negative relationship with miR-590-5p. Taken together, LOXL1-AS1 promoted Ox-LDL induced angiogenesis via regulating miR-590-5p-modulated KLF6/VEGF signaling pathway. The LOXL1-AS1-miR-590-5p axis exerts a novel role in the progression of atherosclerosis.

Rational design of catalyst layers in a membrane electrode assembly (MEA) is crucial for achieving high-performance polymer electrolyte membrane fuel cells. Establishing a clear understanding of the property (catalyst ink)–structure (catalyst layer)–performance (MEA) relationship lays the foundation for this rational design. In this work, a synergistic approach was taken to correlate the ink formulation, the microstructure of catalyst layers, and the resulting MEA performance to establish such a property–structure–performance relationship. The solvent composition (n-PA/H2O mixtures) demonstrated a strong influence on the performance of the MEA fabricated with an 830-EW (Aquivion) ionomer, especially polarization losses of cell activation and mass transport. The performance differences were studied in terms of how the solvent composition affects the catalyst/ionomer interface, ionomer network, and pore structure of the resulting catalyst layers. The ionomer aggregates mainly covered the surface of catalyst aggregates acting as oxygen reduction reaction active sites, and the aggregate sizes of the ionomer and catalyst (revealed by ultrasmall angle X-ray scattering and cryo-transmission electron microscopy) were dictated by tuning the solvent composition, which in turn determined the catalyst/ionomer interface (available active sites). In n-PA/H2O mixtures with 50∼90 wt % H2O, the catalyst agglomerates could be effectively broken up into small aggregates, leading to enhanced kinetic activities. The boiling point of the mixed solvents determined the pore structure of ultimate catalyst layers, as evidenced by mercury porosimetry and scanning electron microscopy. For mixed solvents with a higher boiling point, the catalyst–ionomer aggregates in the ink tend to agglomerate during the solvent evaporation process and finally form larger catalyst–ionomer aggregates in the ultimate catalyst layer, resulting in more secondary pores and thus lower mass transport resistance. Both the enlarged catalyst/ionomer interface and appropriate pore structure were achieved with the catalyst layer fabricated from an n-PA/H2O mixture with 90 wt % H2O, leading to the best MEA performance.

The objective of this study was to evaluate the effects of adding formic acid and corn flour supplementation to banana pseudostem silages on the nutritional quality of these silages, growth, digestion, rumen fermentation and cellulolytic bacterial community of Nubian black goats fed these silages. Banana pseudostem silage was prepared either conventionally without any additives (CON) or mixed with 0.6% formic acid (F), 10% corn flour (C), or both (F+C). Four experimental diets containing 40% of the corresponding silages were designed with roughage to concentrate ratio of 50:50 (dry matter (DM) basis). A total of 48 Nubian black castrated goats (body weight (BW), (22.64±1.82) kg; 4-mon-old) were randomized into one of the four treatment groups with 12 replicates of one castrated goat per replicate for each treatment in a completely randomized design. Each group was fed on one of the four experimental diets for 40 days. A factorial arrangement of treatments of 2 (formic acid levels: 0 and 0.6%)×2 (corn flour: 0 and 10%) was adopted. Formic acid supplementation increased (P<0.05) average daily gain, as well as lactic acid, propionate and butyric acid and water-soluble carbohydrate concentrations, but decreased (P<0.05) the feed conversion rate, pH value, acetate/propionate ratio, and butyric acid concentration relative to the CON group. Corn flour supplementation increased (P<0.05) the apparent digestibility of crude protein, neutral detergent fiber, and non-fibrous carbohydrate and Fibrobacter succinogenes, Ruminococcus albus,and Butyrivibrio fibrisolvenspopulations, but decreased (P<0.05) the Ruminococcus flavefacienspopulation relative to the CON group. There were no F×C treatment interactions (P>0.05) for any of the other indices except for the apparent digestibility of non-fibrous carbohydrate (NFC) (P<0.05). The results demonstrated that adding 0.6% formic acid and 10% corn flour supplementation to banana pseudostem silages improved the nutritional quality of these silages and enhanced the growth performance of Nubian black castrated goats by improving apparent nutrient digestibility, and regulating ruminal fermentation and bacteria populations.

The shape dependence for the technologically important nickel oxide (NiO) on (001) strontium titanate substrate nanocrystal material systems is investigated under the generalized Wulff–Kaishew (GWK) theorem framework. It is found that the shape of the NiO nanocrystal is primarily governed by the existence (or absence) of interfacial strain. Nanocrystals that have a fully pseudomorphic interface with the substrate (i.e., the epitaxial strain is not relaxed) form an embedded smooth ball-crown morphology with {001}, {011}, {111}, and high-index {113} exposed facets with a negative Wulff point. On the other hand, when the interfacial strain is relaxed by misfit dislocations, the nanocrystals take on a truncated pyramidal shape, bounded by {111} facets and a {001} flat top, with a positive Wulff point. Our quantitative model is able to predict both experimentally observed shapes and sizes with good accuracy. Given the increasing demand for heteroepitaxial nanocrystals in various physiochemical and electrochemical functional devices, these results lay the important groundwork in exploiting the GWK theorem, particularly as a general analytical approach to predict nanocrystal growth on oxide substrates, in terms of their sizes and morphology dependencies, when governed by interface strain.

Pyrethroid resistance in the redlegged earth mite, Halotydeus destructor(Tucker), is primarily attributed to a kdr(knockdown resistance) mutation in the parasodium channel gene. To assess fitness costs associated with this resistance, adult resistant and susceptible populations were mixed in different proportions in microcosm tubs and placed in a shade-house simulating field conditions. Three separate experiments were undertaken whereby parental mites were collected from the field and offspring were followed for two to three generations. The association between fitness costs and kdr-mediated resistance was investigated by examining differences in mite numbers and changes in resistant allele frequencies across generations. In two (of the three) experiments, the population fitness measure of mites was significantly lower in microcosms containing a higher proportion of resistant individuals compared with treatments containing susceptible mites. No differences in mite fitness were observed between treatments in the third experiment; in this instance, the starting proportion of individuals homozygous for the resistant mutation was much lower (~40%) than in the other experiments (>90%). In all three experiments, a decrease in the resistant allele frequency across mite generations was observed. These findings indicate a potential deleterious pleiotropic effect of the kdrmutation on the fitness of H. destructorand have implications for resistance management strategies aimed at this important agricultural pest. Further experiments investigating fitness costs directly in the field are warranted.

In this study, long term observations of medium frequency (MF) radar at Langfang site (39.4°N, 116.7°E) from 2009 to 2020 have been used to analyze the dependence of the 11‐year solar cycle on horizontal winds in the local mesosphere and lower thermosphere (MLT). The results show that the zonal wind is positively correlated with solar activity during spring at 80–84 km, and during summer at 80–82 km; the meridional wind is positively correlated with solar activity during spring at 84–88 km and during summer at 84–90 km. In contrast, the results show no correlation between the horizontal wind and solar activity in autumn and winter. We attempt to explain the correlations in terms of the changes in stratospheric temperature and the net flux of gravity waves during solar activities. In addition, annual and semiannual oscillations of the zonal/meridional wind were found by using the least squares fitting method on daily horizontal winds, which show negative correlations with solar activity at heights of 80–90 km. The responses of atmospheric horizontal wind and tides at the height of 80–100 km to 11‐year solar activities are analysed.The zonal/meridional wind is positively correlated with solar activities in spring and summer, and the amplitude of annual and semiannual oscillations of the zonal/meridional wind is mainly negatively correlated with solar activities.A mechanism is proposed that the solar activities could affect the stratospheric thermal and wind structure, leading to change of upward propagating gravity wave net flux, and finally affect the MLT atmospheric wind field. The responses of atmospheric horizontal wind and tides at the height of 80–100 km to 11‐year solar activities are analysed. The zonal/meridional wind is positively correlated with solar activities in spring and summer, and the amplitude of annual and semiannual oscillations of the zonal/meridional wind is mainly negatively correlated with solar activities. A mechanism is proposed that the solar activities could affect the stratospheric thermal and wind structure, leading to change of upward propagating gravity wave net flux, and finally affect the MLT atmospheric wind field.

Chemical strategies to manage pest populations that have evolved pesticide resistance can involve killing resistant individuals by using higher rates of the same pesticide or applying alternative pesticides for which resistance does not exist. However, the dilemma is that alternative pesticides available for many pest species are limited, while higher pesticide rates may lead to the evolution of higher resistance levels. Here, both strategies are tested in a resistant population of the redlegged earth mite, Halotydeus destructor, which contained resistance against two groups of chemicals: synthetic pyrethroids and organophosphates. Resistant mites were introduced into exclusion field plots, which were then treated with pyrethroid, organophosphate or alternative chemicals for 2 years at a low pressure (one spray at the registered field rate per year) or a high pressure (two sprays at the registered field rate per year). A single pyrethroid application suppressed mite numbers, but pyrethroid-resistant allele (kdr) frequencies quickly rose from ∼50% to nearly 100%. Thereafter, pyrethroid chemicals lost effectiveness. However, kdr frequencies declined across mite generations when pyrethroids were not used, regardless of other treatments. Organophosphates continued to suppress mite populations under both high and low pressures, irrespective of kdr allele frequencies, and laboratory bioassays showed no increase in organophosphate resistance levels. One of the alternative chemicals, diafenthiuron, applied once per year over two years, successfully suppressed mite numbers, whereas other treatments did not control mites. These findings demonstrate that different strategies are required to manage H. destructor with pyrethroid resistance and organophosphate resistance.

Three-dimensional (3D) adsorption materials have attracted ever-increasing interest as a cost-effective tool to remove antibiotics from water. However, how to effectively enhance the adsorption capacity of the adsorbents is still a great challenge. In this study, a novel method for fabricating 3D porous carbon nanofiber/graphene oxide composite aerogels (PCNF/GOAs) with an adjustable pore structure was developed for antibiotic removal from water using electrospinning-liquid assisted collection technology. By adding poly(methyl methacrylate) (PMMA) as a pore-forming agent, the volume of pores corresponding to the tetracycline (TC) size (0.8–2 nm) increased twelve-fold, and the adsorption capacity increased nine-fold. To evaluate the feasibility of PCNF/GOAs as a potential adsorbent for antibiotic removal, batch and fixed-bed experiments were conducted. The results showed that PCNF/GOAs effectively removed TC from water over a wide pH range (4–10), and the maximum adsorption capacity was more than 900 mg g−1at pH 7. The experimental data for the adsorption of TC onto PCNF/GOAs better fitted the pseudo-second-order kinetic and Temkin models. Due to its self-supporting characteristic, 3D PCNF/GOAs generated lower inlet pressure compared to traditional particle adsorbents in fixed-bed column adsorption. π–π electro-donor–acceptor (EDA) interaction, pore filling and hydrogen bonding are the main possible mechanisms for the adsorption of TC on PCNF/GOAs.

The Yangtze River Economic Belt (YREB) spans three terrain steps in China and features diverse topography that is characterized by significant differences in geological structure and present-day crustal deformation. Active faults and seismic activity are important geological factors for the planning and development of the YREB. In this paper, the spatial distribution and activity of 165 active faults that exist along the YREB have been compiled from previous findings, using both remote-sensing data and geological survey results. The crustal stability of seven particularly noteworthy typical active fault zones and their potential effects on the crustal stability of the urban agglomerations are analyzed. The main active fault zones in the western YREB, together with the neighboring regional active faults, make up an arc fault block region comprising primarily of Sichuan-Yunnan and a “Sichuan-Yunnan arc rotational-shear active tectonic system” strong deformation region that features rotation, shear and extensional deformation. The active faults in the central-eastern YREB, with seven NE-NNE and seven NW-NWW active faults (the “7-longitudinal, 7-horizontal” pattern), macroscopically make up a “chessboard tectonic system” medium-weak deformation region in the geomechanical tectonic system. They are also the main geological constraints for the crustal stability of the YREB.

Student mental health issues remain a significant global concern, imposing considerable health, social, and economic burdens. China has also published numerous national policies prioritizing this area. To further investigate the current prevention and intervention programs, we conducted a scoping review, searching six databases (three in English and three in Chinese) up to May 2024. A total of 77 eligible studies were included. Our findings highlight several gaps in current practices, such as regional disparities in school-based mental health programs, insufficient focus on younger children and developmental issues, limited comprehensive pathways from screening to classification, prevention, and intervention, and a lack of an integrated approach to promoting mental health among children and adolescents. These findings indicate an urgent need for improvements in this field, calling for future studies to help reduce the burden of mental health problems and support the holistic development of children in China.

3D free bending process, an advanced metal forming technology, has attracted much attention due to its unique geometrical flexibility and efficiency. Filling tubes with materials may effectively reduce the distortion in the cross-section area and restrain wrinkling and collapse of tube wall. In the present study, the impacts of filling different materials on the copper tubes during 3D free bending process were investigated. We have found that copper tubes filled with low melting point alloys could induce the most uniform stress distribution, which result in better formability and moderate thickness changing rates when compared to SS304 steel balls and PU rubbers. The lowest ellipticity reached to 1.467%.

Incremental flanging (IF) has emerged as a flexible and low-cost alternative to conventional stamping processes suitable for rapidly producing multi-variety and small-batch flanged parts. However, due to the material hardening as well as large and unevenly distributed springback, it is still challenging to manufacture and control the forming quality of large-size open-edge flanged parts with a length of more than 1.0 m, a width of more than 100 mm and a flange height of more than 30 mm. In the present work, combining the advantages of robotic motion and incremental flanging, Robot-assisted incremental flanging (RAIF) technology was proposed to utilize a robot-guided roller to progressively bend the sheet to the desired flanging angle. As a typical path control-based flexible forming technology, two different toolpath strategies were proposed, corresponding generation algorithms were deduced, and the effects of the proposed toolpath strategies were compared. The results demonstrated that the SRAIF strategy, which synchronizes the rotation and revolution of the rollers, can effectively guide material flow along the circumferential direction to suppress the generation of edge waves and reduce springback, thereby significantly improving the geometric accuracy of the flanged parts. Further, the effect of the critical parameters was investigated. The results indicated that the farther the flanging starts from the free end, the magnitude of springback angle increases. As the rotation velocity of the roller increases, the geometric accuracy of the flanged parts deteriorates.

Over-fitting is a significant threat to the integrity and reliability of deep neural networks with generous parameters. One problem is that the model learned more specific features than general features in the training process. To solve the problem, we propose an adversarial training method to assist the model in strengthening general representation learning. In this method, we make a classification model as a generator Gand introduce an unsupervised discriminator Dto distinguish the hidden feature of the classification model from real images to limit their spatial distance. Notably, the Dwill fall into the trap of a perfect discriminator resulting in the gradient of confrontation loss of 0 after overtraining. To avoid this situation, we train the Dwith a probability Pc. Our proposed method is easy to incorporate into existing frameworks. It has been evaluated under various network architectures over different fields of datasets. Experiments show that this method, under low computational cost, outperforms the benchmark by 1.5–2 points on different datasets. For semantic segmentation on VOC, our proposed method achieves 2.2 points higher mAP.

An atom-based aggregation structure for oligomer-like polycarbosilane (PCS) was constructed by simulating multiple molecules composed of six-type silicon–carbon linear and ring units. A critical length was defined via the pair distribution function transferred from the wide-angle X-ray scattering curve and used to characterize the average particle size of PCS. The results revealed that the PCS molecules were untangled from each other, and every molecule formed an ellipsoidal-like particle. The average size of single-molecule particles predicted by the atom-based aggregation model was 1.4 nm for PCS with a number-average molecular weight of ∼1200 g/mol, which was comparable with those evaluated on the basis of the synchrotron radiation small-angle X-ray scattering data for extremely diluted ethanol solutions consisting of PCS and the wide-angle X-ray scattering data for PCS powders. The single-molecule particles in PCS had a fractal type of mass, suggesting a microporous structure.

Additive manufacturing (AM), also known as three-dimensional printing, is gaining increasing attention from academia and industry due to the unique advantages it has in comparison with traditional subtractive manufacturing. However, AM processing parameters are difficult to tune, since they can exert a huge impact on the printed microstructure and on the performance of the subsequent products. It is a difficult task to build a process–structure–property–performance (PSPP) relationship for AM using traditional numerical and analytical models. Today, the machine learning (ML) method has been demonstrated to be a valid way to perform complex pattern recognition and regression analysis without an explicit need to construct and solve the underlying physical models. Among ML algorithms, the neural network (NN) is the most widely used model due to the large dataset that is currently available, strong computational power, and sophisticated algorithm architecture. This paper overviews the progress of applying the NN algorithm to several aspects of the AM whole chain, including model design, in situmonitoring, and quality evaluation. Current challenges in applying NNs to AM and potential solutions for these problems are then outlined. Finally, future trends are proposed in order to provide an overall discussion of this interdisciplinary area.

In the Bering Sea, summer dimethylsulfide (DMS) and dimethylsulfoniopropionate (DMSPd and DMSPp) exhibited substantial spatial and interannual variations during 2012–2016, encompassing both cold (2012) and warm (2014 and 2016) temperature regimes. Summer average chlorophyll a, DMS, and DMSPd concentrations in the upper water increased significantly, paralleling a 1.6 °C increase in seawater temperature. High DMS/DMSPp regions in the upper 50 m at 177°E–175°W extended both north‐eastward and south‐westward, which were associated with elevated phytoplankton biomass and concurrent proportion of dinoflagellates in phytoplankton community in warm years. Simultaneously, these patches spread vertically throughout the upper 200 m in warm years, which corresponded with rapid bacteria consumption and abundant small copepods at the 50–200‐m layer in 2014 and 2016. Starting from 4.88 μmol/(m2day), summer average DMS fluxes increased sharply by threefold to fivefold in response to a warming of 2.8 °C in the surface water during 2012–2016. The Bering Sea has undergone a warming and responds rapidly to climate change on temporal scales. The resulting marine ecosystem reorganization in the Bering Sea has the potential to exert profound impacts on the local marine biogeochemical cycles and the sea‐to‐air fluxes of dimethylsulfide (DMS). Data on temporally detailed DMS and DMSP measurements in the Bering Sea are rare. Three summer cruises to the Bering Sea, one covering the cold year (2012) and two covering warm years (2014 and 2016), provided an opportunity to study how oceanic biogenic dimethylated sulfur compounds may respond to spatiotemporal variations to ocean warming resulting from climate change. Seawater warming of 1.6 °C in the upper layer of the basin‐slope‐shelf section from cold to warm years was accompanied by elevated phytoplankton biomass, further leading to increases in DMS and DMSPd concentrations. Both vertical and horizontal extensions of high DMS/DMSPp patches at 177°E–175°W from 2012 to 2016 were caused by variations in plankton biomass and community structure. Summer DMS sea‐to‐air fluxes increased sharply by threefold to fivefold due to a coincident warming of 2.8 °C in the surface water, which would exert climate cooling effects inverse to those of the CO2built up in the Bering Sea. Interannual ascending trends in Chl a, DMS, and DMSPd concentrations corresponded with seawater warming of 1.6 °C in the upper waterBoth vertical and horizontal extensions of high DMS/DMSPp patches were caused by variations in plankton biomass and community structureSummer DMS fluxes increased sharply by threefold to fivefold due to a warming of 2.8 °C in the surface water

The carbon supported palladium-copper alloyed catalysts (Pd-Cu/C) were synthesized by a facile two-step method with different molar ratios of Cu to Pd (Cu/Pd), namely, Cu/Pd = 2.0, 3.0, 4.0, and 5.0. The Cu nanoparticles were obtained by microwave assisted method, and followed by galvanic substitution of Pd on Cu nanoparticles. The as-prepared Pd-Cu/C exhibited mainly fcc phase with the average crystallite sizes ranging 4.0[?]4.5 nm by varying Cu/Pd ratios of 2.0[?]5.0. The degree of Pd-Cu alloying was significantly influenced by Cu/Pd ratios, which ultimately affected the activity toward oxygen reduction reaction (ORR) and stability of Pd-Cu/C. The best ORR activity with good stability was obtained for the Pd-Cu/C prepared with Cu/Pd = 4.0 owing to the formation of fcc PdCu alloy structure. The half-wave potentials (E1/2) reached 0.76 and 0.86 V (vs. RHE) in HClO4 and KOH solutions, respectively, which were comparable to those of commercial Pt/C, while the E1/2 values remained virtually unchanged after 1000 cycles. However, the limiting current density decreased by 12.7% in HClO4, resulted in 58.5% loss of electrochemical surface area due mainly to Pd-Cu dealloying. The maximum power densities of 315 and 181 mW[?]cm[?]2 were achieved with Pd-Cu/C at 0.10 mg Pd*cm[?]2 in the H2/O2 and H2/air single cells, respectively.

Focusing on the Yangtze River economic zone, the previous geological researches are systematically summarized, resources and environment conditions and major geological problems which are needing to be concerned in land planning and construction are studied. The results show that the resource conditions of cultivated land, shale gas, geotherm, lithium and so on are superior in the Yangtze River economic zone, and the resources and environment conditions are conducive to develop the modern agriculture, clean energy industry and strategic emerging industries. 3×1013m2farmlands without heavy metal pollution are concentrated; there are three national level shale gas exploration and development bases with explored reserves of 5.441×1011m3; geothermal availability is 2.4×109t of standard coal each year, equivalent to 19% of the amount of coal in 2014; Asia’s largest energy lithium metal ore deposit is found. In some parts of Yangtze River economic zone, there are some major geological problems such as active faults, karst collapse, ground subsidence, landslide-collapse-debris flow, affecting the river-crossing channels, high-speed railway, urban agglomeration and green ecological corridor planning and construction. Those problems should be concerned, and the relevant suggestions and countermeasures are put forward. Meanwhile, the ideas to further support the development of the Yangtze River economic zone are put forward.

The carbon supported PdCu alloyed catalysts (PdCu/C) with different molar ratios of Cu to Pd (Cu/Pd), namely, Cu/Pd=2.0, 3.0, 4.0, and 5.0, were synthesized by a simple and facile two-step method. The Cu nanoparticles were first obtained by microwave assisted method, and then followed by galvanic substitution of Pd on Cu nanoparticles. The PdCu/C catalysts exhibited mainly cubic phase with the average crystallite sizes ranging 4.0~4.5 nm by varying the Cu/Pd ratios of 2.0~5.0. The microstructure and the activity toward oxygen reduction reaction (ORR) of PdCu/C were significantly influenced by the Cu/Pd ratios. The higher degree of alloying and better ORR activity could be achieved with the Cu/Pd=4.0. The half-wave potential (E1/2) reached 0.760 V in the acid medium, which was only 40 mV lower than that of commercial Pt/C. Only 20 mV (2.6%) decrease in E1/2 after 1000 cycles between 0.4 and 1.0 V suggested the good stability.

Different sulfur modified carbon coated lithium iron silicate (Li2FeSiO4/C) composites were prepared by sol-gel precursor and solid-state reaction using 1-dodecanethiol as a sulfur source material. The effects of sucrose amount, sulfur content, sintering temperature and sintering time on crystal structure, surface morphology and electrochemical performance of sulfur modified Li2FeSiO4/C composites were investigated through orthogonal design experiments. The results of the orthogonal investigation indicated that the significance of the influence on the capacity performance followed the decreasing order as sulfur doping content > sucrose content > sintering temperature > sintering time. The optimized conditions were determined to be: sucrose content of 70%, sulfur doping content of 10%, sintering temperature at 600degC for 7 h.

Dynamic Time Sweep of Rotational Rheometer has been Used to Study the Variation in Rheological Properties of Polymers with Time. Polycarbosilane (PCS) is a Solid Oligomer at Room Temperature and Becomes Melt at its Softening Temperature. Bubbles are Unavoidably Produced by Gasification of Low Molecular Weight Part of PCS, which Significantly Disturbs the Subsequent Rheological Measurement. however, the Rheological Data of PCS Melt Cannot Be Repeated on Conventional Dynamic Time Sweep Test even after Reducing the Bubble. in this Work, a Series of Oscillatory Rheological Measurements were Carried out by Temperature Control to Improve the Data Reliability. the Axial Force Data of PCS Melt were Manually Recorded and Compared before and during the Test, which Reflected the Response of PCS Melt to Temperature Change. the Results Confirmed that the Shear Stress of PCS Melt was Readily Affected by Temperature Alteration. the Data Repeatability of the Rheological Test was Evidently Improved for PCS Melt with the Temperature Control.

Shear stress-shear strain rate and shear stress-shear time curves of epoxy resin samples with the number average molecular weight of 283 g/mol were measured at 50 °C under the modes of steady test and transient test, respectively. Effects of dealy time (t1) and measurement time (t2) on the shear stress-shear responses of the epoxy resin oligomer material were studied. It was found that the repeatability of the test results at small shear rates was significantly influenced by the delay time and the measurement time. The values of t1 and t2 parameters to be used for the steady test of epoxy resin oligomer material could be optimized based upon the transient test. The measurement repeatablity at shear rates smaller than 7 s-1 was apparently improved by setting the delay time and the measurement time longer than 20 s seperately (t1 ³ 20 s, t2 ³ 20 s) with the total delay time and the measurement time shorter than 80 s (t1 + t2 £ 80s).

A small amount of ruthenium (Ru) was introduced into binary CoSe2/C through chemical reduction to obtain ternary Ru(CoSe2)/C. The effects of heat-treatment (HT) on crystal structures and electrocatalytic activities toward oxygen reduction reaction (ORR) of binary and ternary catalysts were investigated. Upon the heat-treatment at 400degC, a simple phase transformation from orthorhombic to cubic CoSe2 took place in the absence of Ru, resulting in larger crystallite size and poorer ORR activity of CoSe2/C-HT. However, with the incorporation of Ru, a new cubic (RuxCoy)Se2 like phase might be formed as the Ru could enter the CoSe2 lattice during the phase transformation, which not only prevented the grain growth and stabilized the structure, but also provided the new efficient ORR active site. Ultimately, high activity and excellent stability were achieved for Ru(CoSe2)/C-HT with the synergy of Ru with Co and Se, which significantly enhanced Ru utilization. The open circuit potential and maximum power density reached 0.87 V and 151 mW*cm[?]2 in the H2/O2 single cell test, respectively, which were 24.3% and 242.5 times larger than those of CoSe2/C-HT (0.70 V and 0.62 mW*cm[?]2), respectively. The normalized degradation was 2.2% after 1000 cycles during the accelerated degradation test.

Carbon supported ruthenium tellurium (RuTe2/C) catalysts were synthesized with various Ru/Te ratios (2:1, 1.5:1, 1:1, 1:2, and 1:3) via a microwave route followed by heat-treatment. Effects of Ru/Te ratio on crystal structures, microstructures, chemical states and electrocatalytic activities toward oxygen reduction reaction (ORR) of RuTe2/C were systematically investigated. A mixed phase with predominant orthorhombic RuTe2 and minor hexagonal Ru was identified. A novel synergistic effect was provided by RuTe2 and Ru which acted as dual ORR active sites. The average particle sizes ranged 5.0 [?] 8.4 nm, while the half-wave potentials (E1/2) varied 0.57 [?] 0.61 V in HClO4 and 0.70 [?] 0.72 V in KOH as the Ru/Te ratios changed from 2:1 to 1:3. The largest E1/2 values of 0.61 V and 0.72 V, as well as the E1/2 losses of 0.83% and 0.69% upon 1000 cycles or 3.28% and 0.97% (containing 2 mol*L[?]1 methanol) were obtained for the RuTe2/C (Ru/Te = 1:1) in HClO4 and KOH, respectively, showing the best ORR activity and excellent stability with high methanol tolerance in both acidic and alkaline media. The preliminary cell performance revealed the maximum power density of 269 mW*cm[?]2 with impressive durability.

In high-speed railway (HSR), the increasing demand for wireless communication and high-speed broadband leads to higher energy consumption by the system. To improve energy efficiency (EE) and fair allocation of resources in multi-user communication, an algorithm combining the BFGS algorithm and the Armijo criterion is used. Firstly, an EE optimisation model of the system is constructed by considering the constraints, such as the average transmitting power of the evolved Node B (eNB), the minimum transmission rate and fairness among users. Secondly, the objective function is transformed into a convex optimisation problem through equivalent transformation. Finally, an algorithm combining the BFGS algorithm and the Armijo criterion is used to solve the objective function and then determine the power allocation scheme for each moment of the system. The simulation results show that the proposed scheme shows a better performance in terms of EE than the traditional algorithm in the same scenario over time. Under different user numbers and proportional rate constraint conditions, the adopted scheme can optimise system EE while satisfying the user communication fairness threshold. In addition, compared with the traditional power allocation scheme, the proposed algorithm is significantly improved in terms of eNB transmit power, fairness and EE performance.

The horizontal/geographical variations in dissolved dimethylsulfide (DMS), its precursor dimethylsulfoniopropionate (DMSPd and DMSPp), and chlorophyll a(Chl a), as well as the oceanographic parameters influencing the concentrations of dimethylated sulfur compounds, were investigated in the Bering Sea from July to August 2012. Similar to Chl a, the surface DMS and DMSPp levels, as well as DMS(P) production and consumption rates, exhibited a declining gradient from the central basin to the continental shelf, with high‐value areas appearing in the central basin, the slope regions, and Anadyr Strait but a low‐value area occurring on the outer‐middle continental shelf. Considerably high values of DMS and DMSP were measured in the saline Bering Sea Basin Deep Water (>2,000 m) located at the southwest of the Bering Basin because of the release of resuspension in 2,000 m depth and the DMSP production from endogenous benthic bacteria and cyanobacteria population. Chl awas positively correlated with DMSPp and DMS in the surface waters and the upper water of the basin, whereas significant negative correlations were found between DMS and nutrients (dissolved inorganic nitrogen [DIN], phosphorus, and silicate) in the inner shelf of the Bering Sea. DMS microbial consumption was approximately 6.26 times faster than the DMS sea‐air exchange, demonstrating that the major loss of DMS in the surface water occurred through biological consumption relative to evasion into the atmosphere. Average sea‐to‐air DMS fluxes were estimated to be 4.66 μmol/(m2·d), and consequently oceanic biogenic DMS emission had a dominant contribution to the sulfur budget over the observational area. The surface DMS and DMSPp levels exhibited a declining gradient from the central basin to the continental shelfSignificant levels of DMS and DMSP were observed at depths of up to 2,000 m in the southwest saline Bering Sea Basin Deep WaterBiological consumption, relative to ventilation, is a predominant mechanism in DMS removal from the surface water

A series of different vanadium modified carbon coated lithium iron silicate (Li2Fe1-xVxSiO4/C) composites were prepared by sol-gel precursor and solid-state reaction using ammonium metavanadate (NH4VO3) as a vanadium source material. The effects of vanadium content, sucrose amount, sol-gel time and type of carboxylate acid on crystal structure, surface morphology, elemental composition and electrochemical performance of Li2Fe1-xVxSiO4/C composites were investigated through orthogonal design experiments. The initial discharge capacity of the nominal 35% vanadium modified Li2FeSiO4/C, prepared under the optimized conditions (sucrose amount of 80% and sol-gel time of 2 h using citric acid as a pH regulator), reached as high as 216.7 mAh/g (corresponding to 1.30 moles per formula unit) at 0.1C and room temperature. The composite exhibited a mixed Pmn21 and P21 phase with the coexistences of metallic iron (Fe) and lithium silicate (Li2SiO3) as the main impure phases.

Capability of obtaining high capacity by exchanging more than one lithium ion has made lithium iron silicate (Li2FeSiO4) very attractive to be an ideal cathode material for lithium ion batteries. However, high deintercalation voltage and large deformation are expected during the delithiation of the second lithium ion. In this work, the nominal 2% sulfur doped carbon coated Li2FeSiO4 composite was prepared by sol-gel precursor and solid-state reaction method. The results revealed that a well crystallized Pmn21 phase was formed, and no common impurities including iron oxide and lithium silicate were identified. The initial discharge capacity of 229.2 mAh*g-1 was obtained at 0.1C and room temperature, which corresponds to 1.38 moles lithium ions per formula unit. The capacity fluctuated to 185.6 mAh*g-1 after 50 cycles, achieving the capacity retention of 81%.