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DPOB molecules passivated interface defects, released residual strain, and induced band bending to enhance hole extraction and transport. The champion PCE of CsPbBr3PSC achieved 10.87%.

An interphase migration and enrichment model of lead and zinc during molten copper slag depletion was established. The occurrence of various components in copper slag was predicted using sulfur−oxygen potential calculations and confirmed through high-temperature experiments. The recovery rate of copper can reach 90.13% under the optimal conditions of 1200 °C, an iron to silicon mass ratio of 1.0, 3 wt.% ferrous sulfide, and a duration of 45 min. Lead (54.07 wt.%) and zinc (17.42 wt.%) are found in the flue dust as lead sulfate, lead sulfide, and zinc oxide, while copper matte contains lead (14.44 wt.%) and zinc sulfide (1.29 wt.%). The remaining lead and zinc are encapsulated as oxides within the fayalite phase.

To comprehensively utilize the low-iron high-vanadium–titanium magnetite, a new method of vortex smelting reduction of vanadium–titanium magnetite was proposed, and the enrichment and reconstitution regularity of Ti-bearing phases in the slag was investigated through X-ray fluorescence spectrometry, X-ray photoelectron spectroscopy, X-ray diffraction analysis, and optical microscopy. The phase diagram revealed that the preferential crystallization of MgTi2O5can be achieved by adjusting the CaO, MgO, and TiO2contents of slag. The predominant Ti-bearing phases in the slag obtained from the reduction process are MgxTi3−xO5(0 ≤ x≤ 1) and CaTiO3. FeTiO3is present at carbon–iron ratio (CR) = 1.3, while MgTi2O4and TiC are formed at CR = 1.3. The enrichment of TiO2in the slag increases first and then decreases as the CR increases, and at CR = 1.1, the enrichment of TiO2in the slag reaches 51.3 wt.%. Additionally, the concentrations of MgxTi3−xO5(0 ≤ x≤ 1) and CaTiO3in the slag, along with the grain width of MgxTi3−xO5(0 ≤ x≤ 1), decrease with the increase in CR.

An innovative approach that utilizes a graphite coating treatment (GCT) on precursors of aluminum foam sandwich (AFS) panels was proposed to improve heat transfer efficiency during the powder metallurgical foaming process. The heating and expansion characteristics, effects on cell structures and bending performance of different heat transfer methods were studied. The results indicated that the heating rates of precursors increased by approximately two-fold after applying GCT, resulting in improvements in the expansion ratio, cell size uniformity, and panel surface morphology of the AFS. Furthermore, the later stage of foaming featured a more consistent heating rate, increasing cell roundness and reducing microporous defects within cell walls. These advancements consequently bolstered the bending strength and energy absorption properties of AFS. Notably, GCT technology holds great potential for the production of large-format AFS, as the heat transfer rate remains unaffected by panel size.

In response to the new mechanism of direct vortex melting reduction of vanadium–titanium magnetite, the reaction control mechanism and the migration regularity of valuable components in the process of direct melting reduction were investigated using kinetic empirical equation by fitting and combining with X-ray diffraction, X-ray fluorescence, scanning electron microscopy, energy-dispersive spectrometry, and optical microscopy. The results show that iron reduction is controlled by the mass transfer process of (FeOx) in the slag, while vanadium reduction is controlled by both the mass transfer of (VOx) in the slag and the mass transfer of [V] in the molten iron, and the slag–metal interfacial reaction is the only pathway for vanadium reduction. The reduction of iron and vanadium is an obvious first-order reaction, with activation energy of 101.6051 and 197.416 kJ mol−1, respectively. Increasing the vortex rate and reaction temperature is beneficial to improving the reaction rate and reduction efficiency. The mineral phase variation of iron and vanadium in the slag during the reduction process is Fe2O3→ Fe3O4/FeV2O4→ FeTiO3and FeV2O4→ MgV2O5; titanium in slag is mainly in the form of MgxTi3−xO5(0 ≤ x≤ 1) and CaTiO3. As the reaction time went on, the molar ratio (nTi/nMg) in MgxTi3−xO5(0 ≤ x≤ 1) and the Ti2O3content in the slag gradually went up, while the area proportion of MgxTi3−xO5(0 ≤ x≤ 1) went up and then down, and the porosity of the slag and the grain size of MgxTi3−xO5(0 ≤ x≤ 1) got smaller.

To solve the technical problems of hot metal desulfurization by injecting magnesium particulate, a new idea of hot metal desulfurization by bottom-blowing magnesium vapor was put forward. The reaction mechanism of hot metal desulfurization with magnesium vapor injection was analyzed, and the kinetic model of the desulfurization rate during the process of hot metal desulfurization with magnesium vapor injection was established. The dimensionless equation of the gas–liquid mass transfer coefficient under the injection conditions was obtained by the dimensional analysis method. And the theoretical calculation results were in good agreement with the experimental measurements. The results show that the diameter of the bubbles and the viscosity of the melt significantly affect the desulfurization rate of hot metal injected with magnesium vapor. When the temperature is 1573 K and the gas flow rate is 3 L/min, the desulfurization rate can reach 79% and the utilization rate of magnesium can reach 83%.

In order to increase the contact area and promote the mass transfer process of gas and liquid, the process of the bubble refinement in a metallurgical reactor with mechanical agitation was studied by physical simulation. Based on the capillary number, a prediction equation for the bubble refinement was established. The effects of the gas flow rate, the stirring speed and the stirring depth on the bubble refinement in the reactor were discussed in detail. The distribution of the bubble diameter in the reactor was obtained under different conditions. The results show that when the stirring speed reaches 300 r/min, the bubble diameter mainly distributes in the range of 1–2 mm. A higher gas flow rate may increase the number of bubbles in the melt and promote the bubble refinement process. The mechanism of bubble refinement under mechanical agitation was analyzed, and the results indicated that the stirring speed, the blade area and the blade inclination are the main influencing factors.

To recover copper from copper slag, a novel slag cleaning method was proposed. The thermodynamics and binary phase diagram of FeO–SiO2were calculated first. Then, the effects of experimental parameters on the reduction of Fe3O4, recovery of copper, and slag cleaning mechanism were investigated. The results showed that the addition of SiO2significantly reduced the initial reduction temperature of magnetite and pyrite. The contents of Fe3O4and copper decreased to 2.45 wt.% and 0.39 wt.%, respectively, with copper recovery of 92.52% under the optimum conditions. More than 94% silver and 99% gold subsided into the copper matte after slag cleaning. Approximately 72% of zinc and 75% of lead volatilized in the flue gas. The viscosity of the copper slag decreased from 0.68 to 0.12 Pa·s due to the reduction of magnetite. The sedimentation of copper matte droplets could be enhanced by mechanical stirring.

A homogeneous CuCr50 alloy ingot prepared in situ by thermite reduction-electromagnetic casting is a type of nonequilibrium solidification structure with a Cu matrix supersaturated with Cr. In this study, the effects of heat treatment on the microstructure of the CuCr50 alloy were studied using scanning electron microscopy (SEM), metallography microscopy and transmission electron microscopy (TEM), and the conductivity, macrohardness and tensile strength of the CuCr50 alloy were measured. The obtained results show that the optimal heat treatment conditions are solution treatment (975 °C for 1 h) and aging treatment (500 °C for 2 h), for which the hardness, conductivity, and tensile strength of the CuCr50 alloy are the best; the macrohardness is 103.33 HB, the conductivity is 18.60 MS/m, and the tensile strength is 199.72 MPa. TEM characterization showed that nanosized Cr particles were precipitated and dispersed in the Cu matrix after the aging treatment; the relationship between the precipitates and the Cu matrix was incoherent, and Cu dissolved into the Cr phase in the form of a solid solution to strengthen the second Cr phase.

Web search provides a promising way for people to obtain information and has been extensively studied. With the surge of deep learning and large-scale pre-training techniques, various neural information retrieval models are proposed, and they have demonstrated the power for improving search (especially, the ranking) quality. All these existing search methods follow a common paradigm, i.e., index-retrieve-rerank, where they first build an index of all documents based on document terms (i.e., sparse inverted index) or representation vectors (i.e., dense vector index), then retrieve and rerank retrieved documents based on the similarity between the query and documents via ranking models. In this paper, we explore a new paradigm of information retrieval without an explicit index but only with a pre-trained model. Instead, all of the knowledge of the documents is encoded into model parameters, which can be regarded as a differentiable indexer and optimized in an end-to-end manner. Specifically, we propose a pre-trained model-based information retrieval (IR) system called DynamicRetriever, which directly returns document identifiers for a given query. Under such a framework, we implement two variants to explore how to train the model from scratch and how to combine the advantages of dense retrieval models. Compared with existing search methods, the model-based IR system parameterizes the traditional static index with a pre-training model, which converts the document semantic mapping into a dynamic and updatable process. Extensive experiments conducted on the public search benchmark Microsoft machine reading comprehension (MS MARCO) verify the effectiveness and potential of our proposed new paradigm for information retrieval.

In this communication, a novel reconfigurable antenna operating at both ON- and OFF-body mode is proposed. Initially, the study is dedicated to the construction of omnidirectional and unidirectional radiation using the fundamental TM00 and TM10 mode of the rectangular patch. Then, a rectangular slot is cut out of the patch to shift the resonance of the unidirectional mode to a lower frequency, which not only minimizes the antenna’s overall size but also enables the omnidirectional and unidirectional modes to have overlapping impedance bandwidths. In order to switch arbitrarily, four p-i-n diodes are mounted to control the operating mode. The measured results show that the overlapped bandwidth achieves 3.8% and could cover the 2.4-GHz ISM band. Besides, stable performance of the antenna is obtained when setting on different parts of the human body. The calculated specific absorption rate (SAR) values of both ON- and OFF-body mode meet the standards of the United States and Europe. These properties make the proposed antenna suitable for wearable systems.

The detection and resection of small polyp objects in colonoscopy images are of great significance for the prevention of colorectal cancer (CRC). At present, blurred edges, variable lesion shapes, and intraclass dissimilarity pose challenges for accurately segmenting small polyp objects. In recent years, many deep learning methods based on convolutional neural networks (CNNs) have been proposed and successfully applied to polyp segmentation tasks. However, these methods still have three limitations: 1) limited ability to mine boundary detail information; 2) insufficient ability to capture rich global context information; and 3) introduced additional complex feature extraction operations. To alleviate these challenges, we propose a Fourier transform-multiscale feature fusion network (FTMF-Net) for segmentation of small polyp objects. The core idea includes two points: 1) Fourier transform (FT) module extracts more detailed boundary information and 2) multiscale feature fusion (MFF) module enriches global semantic feature information. FTMF-Net mainly has the following advantages: 1) the proposed model has excellent performance for small polyp object segmentation; 2) this method greatly reduces the complexity of the model without significantly increasing the number of network parameters; and 3) the network is relatively simple and easy to understand. Extensive experiments with 11 state-of-the-art (SOTA) methods on five small polyp object datasets show that our proposed FTMF-Net has superior segmentation performance.

An effective method was reported to prepare low-oxygen Ti powder, which included two experimental steps: the fast conversion of TiO2to TiOx<1powder by self-propagating high-temperature synthesis (SHS) process and the generation of low-oxygen Ti powder by electrodeoxidizing TiOx<1powder at the cathode in molten CaCl2. The key intermediate steps were analyzed by XRD, SEM and electrochemical testing techniques. The results demonstrated that TiOx<1powder (TiO0.325and TiO0.97) was generated after acid leaching MgO in SHS products with TiO2/Mg molar ratio of 1:2, and the TiOx<1powder with 16.3 wt.% oxygen could be transformed into pure titanium powder with 0.121 wt.% oxygen by electrodeoxidation at a constant potential of -3.3 V for 10 h. The electrodeoxidation of TiOx<1powder in CaCl2molten salt follows the step-by-step deoxidation mode, and the lattice of TiOx<1powder after electrodeoxidation shrinks.

Titanium aluminum (TiAl) scraps with a high oxygen content were treated with yttrium (Y) in a liquid chemical deoxidization process for recycling. The Gibbs free energy and the equilibrium constant of the deoxidization reaction were calculated, and the effects of the yttrium content and the system pressure on the oxygen content in the product were determined. The results showed that the oxygen in TiAl scraps could be removed by yttrium, and the oxygen content of the deoxidized TiAl scraps had only 10% of the original content after deoxidization. Furthermore, the oxygen content of the deoxidized TiAl scraps was decreased with the increase of yttrium addition. The higher the chamber pressure, the greater the oxygen content in the final TiAl alloys. These results were consistent with calculated values. The microstructure of the deoxidized alloys was akin to that of the original material; however, Y2O3particles were observed in the deoxidized alloys.

The high-efficiency separation of alloy and slag is fundamental to obtain high-performance CuCr alloys by self-propagating high temperature synthesis metallurgy. In this paper, Cr2O3can determine the basic composition of CuCr alloy through the reduction efficiency, and also participates in the slagging process, which determines the separation effect of slag and alloy. Therefore, the reduction behavior and slagging effect of Cr2O3during the in-situ synthesis of CuCr alloy by aluminothermic reduction is investigated. The results show that the Cr content of the prepared CuCr alloy is 41.3 wt.%∼42.0 wt.% according to the theoretical stoichiometric ratio, and the Cr2O3content in the slag is 16.2 wt.%∼17.0 wt.%. When the Cr2O3dosage is 50% over the theoretical stoichiometric ratio, the Cr content of the prepared CuCr alloy and the Cr2O3content in the slag increases to 47.0%∼47.6 wt.% and 28.4 wt.%∼29.2 wt.%, respectively. With the increase of Cr2O3dosage in the ingredients, the effect of alloy-slag separation is better, the inclusion in the alloy changes from Al2O3inclusion to Cr2O3inclusion, and the relative density of prepared CuCr alloy increases from 90.9% to 98.5%. The overall composition is evenly distributed among the different parts of the alloy. The conductivity of CuCr alloy reaches 15.69 MS m−1, and hardness reaches 95.1 H B.

In order to achieve high-efficiency alkali conversion and impurity removal of high titanium slag under the condition of low alkali concentration, a new way of oxygen-rich alkali conversion in KOH solution was proposed. The conversion law of element occurrence state and the influence of the conversion conditions on the titanium conversion rate and removal rate of silicon and aluminum were studied. The results showed that the KOH solution converted the titanium oxide in high titanium slag into whisker-like potassium titanate. Silicon and aluminum elements were dissolved into the solution. Under the following conditions, KOH concentration of 6 mol/L, conversion temperature of 260 °C, initial oxygen partial pressure of 2 MPa, liquid−solid ratio of 35 mL/g, conversion time of 4 h, and high titanium slag particle size of 48−74 μm, the conversion rate of titanium was 97.0%, and the removal rates of silicon and aluminum were 90.2% and 76.2%, respectively. Oxygen-rich alkali conversion product was converted to rutile with a TiO2grade of 99.1% by acid hydrolysis conversion.

The Al2O3-based slags are playing important roles in the preparation of Cu–Cr alloy through self-propagating high-temperature synthesis (SHS) – Metallurgy method. However, the current research on Al2O3-based slag is mainly concentrated on steel metallurgical slag and electroslag remelting slag, and the research on aluminum thermal reduction slag with high content of Al2O3is still insufficient. Therefore, systematic studies of the physical properties of slag with high aluminum content were carried out in the present work, and the influence of CaF2, CaO, MgO, SiO2, and Na3AlF6on viscosities, liquidus temperatures, densities, and surface tensions of high Al2O3content slags was measured and analyzed. The results indicated that CaO and CaF2have positive effects on the physical properties of Al2O3-based slags, MgO has positive effects when its content is not over 3%, and SiO2and Na3AlF6have negative impacts. CaO, CaF2, and MgO (not over 3%) could be used as additives to improve the metallurgical performance of Al2O3-based slags in aluminothermic reduction–slag refining method.

Darcy's law has been widely used to study the groundwater drainage process within an aquitard. However, non-Darcy flow is frequently encountered in laboratory and in situ investigations. With consideration of a sudden drop in boundary hydraulic heads, aquitard compaction characteristics and their sensitivities to the non-Darcy flow control variables were analyzed. The non-Darcy flow was found to retard groundwater drainage, and the retardation effects were much more significant at early-to-intermediate time points. Under this specific boundary condition, the time–compaction curve in a log–log graph at early time points was found to be close to a straight line, whose slope can be used to indirectly evaluate the extent of the non-Darcy effect. A non-Darcy flow-based type curve method was developed for estimating aquitard hydraulic conductivity (K) and skeletal specific storage (Ss), and this method was used to interpret the time–compaction data recorded in a laboratory experiment. The tested aquitard was determined to be associated with non-Darcy flow due to the fact that the time–compaction curve deviated from the Darcy's law-based theoretical curve. Darcy's law resulted in an underestimated K. In contrast, the estimated Sswas almost unaffected by the flow state, if the observation lasted long enough to reach final steady compaction.

Hotien prefecture, Xinjiang Province, China, in the Taklamakan Desert, is an area of severe iodine deficiency. Because usual methods of iodine supplementation failed here, we began supplementation in 1992 with potassium iodate, which was added to irrigation water (Lancet 1994; 334:107-110). We report 4 y experience with this method in 3 townships that contained a total treated population of 37 000. Potassium iodate was dripped into irrigation water (to a concentration 10-80 [micro]g/l) during a 2- to 4-wk period. During the 3 y that followed, no further supplementation was made, and iodine concentrations increased several fold in crops and plants, sheep and chicken thyroid glands, and meat and in urine of children 2-6 y of age and of women who were of childbearing age. Infant mortality decreased 30%, and sheep production increased 43%. Iodine repletion of soil through irrigation water is an effective and cost-efficient way of providing iodine in appropriate situations., SOUTHERN XINJIANG PROVINCE of the People's Republic of China is an area of severe iodine deficiency. The residents are Uygurs--China's largest minority group, and they are rural, poor, isolated, and [...]

A structure scheme of a pile-based breakwater with integrated oscillating water column (OWC) energy conversion chamber was proposed, and four structure forms had been designed. Based on the physical test, the variations of the reflected wave height, the transmitted wave height, the air velocity at the outlet of the chamber, the air pressure and the wave height in the air chamber were studied under the conditions of different wave heights, periods, with or without elliptical front wall and the baffles on both sides of the chamber. Moreover, based on the results, the changes and relationship between the wave-eliminating effect and energy conversion effect of the scheme were analyzed. In general, it turns out, the transmission coefficients of the four structure forms are kept below 0.5. Furthermore, the transmission coefficients of the structural forms G2, G3, and G4 were all smaller than 0.4, and it is only 0.1 at its smallest. Thereinto, in general, the structure form G4 has the best wave-eliminating and energy conversion performance. At the same time, when the wave steepness is 0.066, the energy conversion and wave dissipation effect of the four structure forms is the best. The research results could be provided as the reference for the design structure selection of pile-based breakwater with integrated OWC energy conversion chamber.

Nitrogen (N) is a major factor affecting rice yield and lodging resistance. Previous studies have primarily investigated the impact of N management on rice lodging in conventional rice monoculture (RM); however, few studies have performed such investigations in rice-crayfish coculture (RC). We hypothesized that RC would increase rice lodging risk and that optimizing N application practices would improve rice lodging resistance without affecting food security. We conducted a two-factor (rice farming mode and N management practice) field experiment from 2021 to 2022 to test our hypothesis. The rice farming modes included RM and RC, and the N management practices included no nitrogen fertilizer, conventional N application, and optimized N treatment. The rice yield and lodging resistance characteristics, such as the morphology, mechanical and chemical characteristics, anatomic structure, and gene expression levels, were analysed and compared among the different treatments. Under the same N application practice, RC decreased the rice yield by 11.1–24.4% and increased the lodging index by 19.6–45.6% compared with the values yielded in RM. In RC, optimized N application decreased the plant height, panicle neck node height, centre of gravity height, bending stress, and lodging index by 4.0–4.8%, 5.2–7.8%, 0.5–4.5%, 5.5–10.5%, and 1.8–19.5% compared with those in the conventional N application practice, respectively. Furthermore, it increased the culm diameter, culm wall thickness, breaking strength, and non-structural and structural carbohydrate content by 0.8–4.9%, 2.2–53.1%, 13.5–19.2%, 2.2–24.7%, and 31.3–87.2%, respectively. Optimized N application increased sclerenchymal and parenchymal tissue areas of the vascular bundle at the culm wall of the base second internode. Furthermore, optimized N application upregulated genes involved in lignin and cellulose synthesis, thereby promoting lower internodes on the rice stem and enhancing lodging resistance. Optimized N application in RC significantly reduced the lodging index by 1.8–19.5% and stabilized the rice yield (>8,570 kg ha–1on average). This study systematically analysed and compared the differences in lodging characteristics between RM and RC, and these findings will aid in the development of more efficient practices for RC that will reduce N fertilizer application.

In response to the increasing report intake and the need for more efficient and effective safety event detection and monitoring in the national airspace system (NAS), this work proposes an automated and sustainable workflow that collectively applies natural language processing (NLP) techniques to the Aviation Safety Reporting System (ASRS) report narratives. The proposed workflow uses latent Dirichlet allocation (LDA), a probabilistic model for uncovering hidden topics within text documents, to perform topic modeling and constructs topic trajectories based on Document Frequency – Inverse Document Frequency (DF−IDF). By applying spectral analysis to the constructed trajectories, we identify multiple periodic and aperiodic topics in unfiltered ASRS report narratives from 2011 to 2021 with minimal human input. Through validation, we confirm that the periodic and aperiodic topics detected can be linked to actual safety events trending in the aviation community and are valuable for safety improvement. Beyond existing topic modeling applications on ASRS reports, this work could deliver more relevant and practical information to safety management experts, not only filling the gap between the topic model output and practical applications but also providing safety management experts with a holistic view of the entire report intake to oversee commonalities. The proposed workflow, with appropriate modifications, has the potential to be adapted to other safety reporting systems.

Objective Cerebral infarction has a poor prognosis and causes a serious burden on families and society. Recombinant tissue plasminogen activator (rt-PA) and urokinase (UK) are commonly used thrombolytic agents in the clinic. However, direct and powerful clinical trial evidence to determine the therapeutic effect of rt-PA and UK on intravenous thrombolysis is lacking.Methods In this study, 180 patients with acute cerebral infarction were treated with rt-PA or UK. The National Institutes of Health Stroke Scale (NIHSS) scores, Barthel index, bleeding complications, and biomarkers were evaluated.Results No significant differences in NIHSS or Barthel scores were found between the groups. However, UK increased the risk of intracranial haemorrhage compared with rt-PA. rt-PA had increased activity in reducing serum levels of MMP-9 than UK.Conclusion Intravenous thrombolysis with rt-PA and UK in the time window of acute cerebral infarction can achieve similar therapeutic effects, but rt-PA can further reduce the risk of cerebral haemorrhage and is relatively safer than UK.

The energetic polymer polyazide glycidyl ether (GAP) is used as the target of a laser ablation micro thruster in the experiment. The specific impulse, momentum coupling coefficient and ablation efficiency of the laser ablated GAP with different concentrations of carbon nanoparticles doping and target thicknesses are measured and the plumes are observed. The mechanism of the carbon nanoparticles doping to improve the propelling performance of the laser ablative polymer target is analyzed and the suitable method of the carbon nanoparticles doping is investigated. Experimental results show that the laser absorption of the polymer is greatly enhanced after doped with the carbon nanoparticles, but the laser ablation propelling performance does not increase obviously with the increase of the doping concentration. The high temperature local hotspots formed by the carbon nanoparticles after absorbing laser energy promote the release of the chemical energy in the polymer, which is the main reason for the improvement of the propulsion performance. The ablation depth of GAP decreases after doping the carbon nanoparticles, which shows the surface absorption characteristic similar to the metal target. With the increase of the target thicknesses, the mass of the incomplete ablative materials increases, and the utilization ratio of the target material is greatly reduced, which leads to the degradation of the polymer propulsion performance. The optimal ablation efficiency of GAP with 3% carbon concentrations in 54 p,m exceeds 250%, which is suitable for a laser ablation micro-thruster. [ABSTRACT FROM AUTHOR]

Unlike global enhancement methods, the proposed algorithm analyses an image in local areas to take full advantage of the local information, and enhances it in two channels to obtain exact result. Furthermore, the algorithm can restrain noise amplification by virtue of local statistic characteristics analysis. To enhance videos rapidly, the Kullback-Leibler distance between frames is used to characterised its similarity, based on it, enhancement function can be updated selectively. Experimental results show that the resultant images from the proposed algorithm are comparable or better than those from previous state-of-the-art methods. On the other hand, the computational complexity of the proposed method is much lower than the current local-data-based contrast enhancement algorithms.

We demonstrate an all-fiber widely wavelength-tunable thulium-doped fiber laser (TDFL) mode locked by a semiconductor saturable absorber mirror (SESAM). The tuning range spans 121 nm, from 1862 nm to 1983 nm. The central wavelength is tuned by a grating-based tunable filter in the ring laser cavity. To the best of our knowledge, this is so far the most widely wavelength-tunable TDFL mode locked by SESAM.

Global warming would deteriorate rice (Oryza sativaL.) quality, especially chalk characteristic. To better cope with the challenges from global warming, the effects of nitrogen (N) fertilizer at heading stage on rice quality under elevated temperature during grain‐filling stage were investigated. Four different growth regimes, including no warming without N fertilizer at heading stage (CK), elevated temperature without N fertilizer at heading stage (ET), elevated temperature with N fertilizer at heading stage (ET+N), no warming with N fertilizer at heading stage (CK+N), were conducted. Elevated temperature during grain filling was achieved by a free‐air temperature enhancement facility with the increase of 4°C in ET and 3.7°C in ET+N. Results showed that elevated temperature decreased rice appearance quality and cooking quality and increased rice nutritional quality and eating quality. Grain‐filling rate and amyloplast development for both superior and inferior spikelets were obviously accelerated during early grain‐filling stage by elevated temperature. The application of N fertilizer at heading stage could inhibit the deterioration of rice quality, particularly for chalk performance, and may be associated with the alleviation of grain‐filling rate and amyloplast development. The above evidence indicated that the application of N fertilizer at heading stage is efficient to mitigate rice quality deterioration under higher temperatures in the Yangtze River Valley.

Vacuum interrupters are important components to ensure the safety of medium and high-voltage power transmission, and contact material is an important factor affecting the performance of vacuum interrupters. CuCr contact materials have been used in most commercial vacuum interrupters. This paper summarizes the research status of the electrical properties of CuCr contacts used in vacuum interrupters, analyses the factors influencing the electrical properties of CuCr contacts, and summarizes the relevant mechanisms, which point out the direction for improving the properties of CuCr alloys and promotes the development of subsequent research on the electrical properties of CuCr contacts. Finally, the electrical properties of CuCr contacts prepared by self-propagating metallurgy based on the Al–CuO–Cr2O3reaction system are summarized.

Microalloying is an effective approach to improve the performance of CuCr alloys. This paper presents a new idea for the preparation of CuCrFe alloys by self-propagation reduction in-situ microalloying. It is found that the addition of Fe alloying components reduces the Gmand ΔGmof the CuCr melt, which inhibits the occurrence of the liquid phase decomposition process. When the Fe content of CuCrFe alloy is 1.5%, compared with the Cr-rich phase of CuCr alloy, the second phase undergoes significant refinement, the average particle size refined from 21.7 μm to 19.3 μm and the standard deviation reduced from 10.59 to 8.73, and the addition of Fe is beneficial to the spheroidization and refinement of the Cr-rich phase. Fe is mainly combined with Cr, and CuCrFe alloy still exists in the form of two phases. After solution+aging treatment, the average particle size of the second phase in CuCr alloy decreases from 21.8 μm to 17.9 μm, and that in CuCrFe alloy decreases from 19.6 μm to 18.6 μm. The conductivity of CuCrFe alloy increases from 10.5 MS·m-1to 15.9 MS·m-1, and the hardness increases from 95.0 HB to 117.0 HB. After heat treatment, the nano-spherical are present in the Cr-rich phase of the CuCrFe alloy, while Fe is completely solid-soluble in the Cr-rich phase; the Cu-rich matrix shows a diffuse distribution of fine second phases, which play a role in strengthening the second phase in the matrix.

As mass transport mechanisms, the spreading and mixing (dilution) processes of miscible contaminated compounds are fundamental to understanding reactive transport behaviors and transverse dispersion. In this study, the spreading and dilution processes of a miscible contaminated compound in a three-dimensional self-affine rough fracture were simulated with the coupled lattice Boltzmann method (LBM). Moment analysis and the Shannon entropy (dilution index) were employed to analyze the spreading and mixing processes, respectively. The corresponding results showed that the spreading process was anisotropic due to the heterogeneous aperture distribution. A compound was transported faster in a large aperture region than in a small aperture region due to the occurrence of preferential flow. Both the spreading and mixing processes were highly dependent on the fluid flow velocity and molecular diffusion. The calculated results of the dilution index showed that increasing the fluid flow velocity and molecular diffusion coefficient led to a higher increasing rate of the dilution index.

Type specimens ofVenturia centaureae,V. chrysanthemi,V. corni,V. helvetica,V. muelleri andV. rhamniare revised, redescribed and illustrated. The diagnosing characteristics ofVenturiaare: ascomata immersed, semi-immersed or superficial, scattered or gregarious, often with papillate ostiole, with or without setae; paraphyses narrowly cellular, hyaline, evanescent in mature ascomata; asci 8-spored, bitunicate, broadly cylindrical to obclavate, usually lacking a pedicel; ascospores pale olivaceous to brown, 1-septate, usually asymmetrical. The distinguishing morphological characteristics ofV. corniare the numerous asci per ascoma, the narrowly fusiform, middle-septate, sub-hyaline to pale brown ascospores, and absence of paraphyses. These characteristics differ from those of other described species ofVenturiaand are more typical for members of Mycosphaerellaceae (Capnodiales). Based on morphological data,V. cornishould be excluded fromVenturia.

The cold flow field in a two dimensional cavity of supersonic combustor has been simulated numerically by using the compressible flow Navier-Stokes equation with the κ-ω SST turbulence model. The flow field structure of different cavity aft wall slope angle (16°,30° and 90°) , different fore aft wall height ratio (1 and 2) and different length depth ratio (3 and 5) are analyzed. The conclusions are as follows: As cavity aft wall slope angle decreases, the compression wave formed at cavity leading separation corner shifts into expansion wave, the shear layer moves into cavity gradually; As cavity fore aft wall height ratio increases from one to two, the expansion wave formed at cavity leading separation corner strengthens and there is no compression wave formed at;As cavity length depth ratio increases from three to five, the compression or expansion wave formed at cavity leading separation corner weakens, cavity bottom wall pressure tends to be constant and aft wall pressure rises.

To clarify the rationality and to provide reasonable usage references of processed Corydalis Rhizoma(CR) in clinic by comparing respectively pharmacological actions including analgesic, anti-inflammation, antiplatelet aggregation and spasmolysis of Yuanhu Zhitong Tablet (YZT) and Yanhusuo Decoction (YD) constituted with raw CR (RCR) or processed CR (PCR).

Rare earth oxide was prepared via direct pyrolysis of rare earth chloride solution. Based on this technique, a new-type jet-flow pyrolysis reactor was designed, and then the fluid dynamics (pressure and velocity) inside the reactor was numerically simulated using a computational fluid dynamics method. The self-produced pressure (p) and the fuel inlet velocity (v) satisfied a quadratic function, p=0.06v2+0.23v−4.49. To fully utilize the combustion-generated heat in pyrolysis of rare earth chloride, an appropriate external pressure p=v2+3v−4.27 should be imposed at the feed inlet. The 1.25- and 1.5-fold increase of feed inlet diameter resulted in decline of adsorption dynamic pressure, but the intake of rare earth chloride increased by more than 30% and 60%, respectively. The fluid flow in the reactor was affected by the feeding rate; the fluid flow peaked near the throat of venturi and gradually smoothed down at the jet-flow reactor's terminal along with the sharp decline of feeding rate.

In this paper, the developed lattice Boltzmann method (LBM) is used to model the solute transport in a filled fracture under a heterogeneous advective velocity field. The results of the developed LBM in modelling the solute transport are compared with the published experimental data. The numerically derived BTCs indicate that the distribution of the filled medium in the fracture has a significant effect on the characteristics of the BTCs, even with the same porosity. The heterogeneity of the filled medium is responsible not only for the heterogeneous advective velocity field but also for the early arrival and long tails of the BTCs. The long tailings of the BTCs increase their length with the increase of the duration of the input pulse. Furthermore, the BTCs obtained from the LBM simulations are well consistent with the two-region model (TRM). The fitting results show that the fractional mobile region varies with the distribution of the filled medium. The long tailings of the BTCs increase their length with the increase of the immobile region while the concentration peak value increases with the increase of the mobile region.

This paper studied the present situation of urbanization in Jilin province, and focused on the ecological environment problems in the process of urbanization, such as the low resource utilization efficiency, serious degradation of grass land and wetland, soil erosion, land desertification, non-point source pollution of agriculture. It is considered the small absorption capacity of environment, insufficient ecological environment construction investment, unreasonable ecological environment construction management system, acute structural environment pollution and the low population quality resulted in the above problems, and it is advisable to promote green urbanization by taking green reform-driven mode, green regulation-driven mode, green industry-guide mode and green lifestyle-led mode.

Tilapia scale was used as the raw material to explore the preparation methods of EGCG adsorption material. Based on the results, the most reasonable interpretation of the data indicates that the EGCG adsorption material preparation process was as follows, particle size 0.30-0.45 mm , preparation temperature 110°C,pH 7 , solid to liquid ratio (g/mL) 1:6, time 20 min . Under this condition, the adsorption capacity of EGCG was 23.53mg/g.

This article studied the wire rope net bottom connection system by an experiment which was researching on four class and seven different kinds materials. Then we get the experiment results by using different anchoring materials as anchoring end and studying the wire rope bottom connection system of tensile bearing capacity. Through the experiment and data analysis, we can draw conclusions that: Application in general situations, we can use M8 stereotypes retractor, but need to expand the curvature of the top ring, while using smooth design scheme to reduce stress concentration. Used in critical situations, we had better use special M14 bolt anchor, which has a higher bearing capacity and security. The presented methods in this paper are feasible and practical.

X-shaped goethite iron oxide crystals were synthesized by a surfactant-free mild hydrothermal synthesis method with the aid of fluorine ions. The X-shaped goethite crystals could readily self-assemble into microscopic hollow spheres through an oil–water interface induced self-assembly method. X-shaped hematite crystals were obtained by phase topotactic transformation of the goethite precursors. The gas sensor properties of X-shaped hematite iron oxide were investigated, and the mechanism for excellent sensor properties was discussed.

To solve the inherent safety problem puzzling the coal mining industry, analyzing the characteristic and the application of distributed interactive simulation based on high level architecture (DIS/HLA), a new method is proposed for developing coal mining industry inherent safety distributed interactive simulation adopting HLA technology. Researching the function and structure of the system, a simple coal mining industry inherent safety is modeled with HLA, the FOM and SOM are developed, and the math models are suggested. The results of the instance research show that HLA plays an important role in developing distributed interactive simulation of complicated distributed system and the method is valid to solve the problem puzzling coal mining industry. To the coal mining industry, the conclusions show that the simulation system with HLA plays an important role to identify the source of hazard, to make the measure for accident, and to improve the level of management.

In this paper, the accuracy of estimating stained non-wetting phase saturation using digital image processing is examined, and a novel post-processing approach for calculating threshold is presented. In order to remove the effect of the background noise of images and to enhance the high-frequency component of the original image, image smoothing and image sharpening methods are introduced. Depending on the correct threshold, the image binarization processing is particularly useful for estimating stained non-wetting phase saturation. Calculated saturation data are compared with the measured saturation data during the two-phase flow experiment in an artificial steel planar porous media model. The results show that the calculated saturation data agree with the measured ones. With the help of an artificial steel planar porous media model, digital image processing is an accurate and simple method for obtaining the stained non-wetting phase saturation.

Say it with flowers:Flower‐like Fe3O4@Fe(OH)3composite catalysts show good activity and stability in the synthesis of cyclic carbonates from epoxides and CO2. The role of hydrogen bonding between the surface hydroxyl groups of the solid and the epoxides at the solid/liquid interface is proposed as a key factor in activating the epoxide and stabilizing the ring‐opened carbonate intermediates.

Emulsion copolymerization of methyl acrylate, styrene, acrylamide, acrylonitrile and homemade cationic monomer was studied. A series of clean cationic polymethyl acrylate emulsion were synthesized using no soap emulsion polymerization. Influence of polymerization conditions such as cationic monomer ratio, electrolyte addition amount, the dosage of initiator on synthetic latex performance and the strengthening effect to paper pulp was studied. It was showed by experimental results that sample No.3 which particle size and zeta potential was 0.142 μm and +29.2 mv respectively was the optimal sample latex. When the dosage of latex No.3 was 1.0% to absolute dry pulp, tensile index and ring crush index of paper was increased by 14.6% and 17.8% respectively.

In this article, the Non-Aqueous Phase Liquid (NAPL) transport in the single filled fracture was studied with the Shan-Chen multi-component multiphase Lattice Boltzmann Method (LBM) with special consideration of wettability effects. With the help of the model, the contact angle of the non-wetting phase and wetting phase interface at a solid wall could be adjusted. By considering a set of appropriate boundary conditions, the fractured conductivity was investigated in condition that the NAPL blocks the channels in the single filled fracture. In order to study the wettability effects on the NAPL transport, a constant driving force was introduced in the Shan-Chen multi-component multiphase LBM. Flow regimes with different wettabilities were discussed. Simulated results show that the LBM is a very instrumental method for simulating and studying the immiscible multiphase flow problems in single filled fracture.

For the lacks of magnesium-based desulfurizer in iron and steel industry, this paper investigated thermodynamics calculation of a new desulfurizer, MgO based desulphurizer. The results indicate that the beginning reaction temperature of light-burned dolomite and Al is 1314℃, the beginning reaction temperature of light-burned dolomite and Si is 1565℃, the beginning reaction temperature of MgO and Al is 1475℃, and the beginning reaction temperature of MgO and C is 1846℃. The reaction temperature between MgO and C is too high, so the carbon-thermal reduction can’t occur easier. When the hot iron temperature is 1400℃ and the addition of alumnium and iron oxide is 12.77%, the reaction between MgO and C will be induced.

According to the characteristics of jumping locomotion, a solution of Tetra-state Hopping Robot (for short: THR) actuated by Shape Memory Alloy Spring (for short: SMAS) is presented in this paper. This article establishes a mechanical model of the jumping robot and analyzes the kinematics and the dynamics of the mechanical model. Lagrange method is applied to analyze the dynamics the mechanical model. Meanwhile, a preliminary explanation of the THR flipping phenomenon during the take-off and flight process is conducted from the perspective of momentum moment.

Residual stresses are determined by different materials and processing parameters so that it is hard to systematically carry on the experimental testing, and it also spends a plenty of time and running costs. Therefore, it is necessary to estimate the residual stresses by mathematical techniques. In this paper, a mathematical method is proposed, and the calculating results are compared with the testing results of alumina and W coatings on various matrixes (process: plasma spraying) that are highly consistent. The calculating results show that the thermal expansion coefficient, substrate preheating temperature and thickness of coating have significant effects on the residual stresses.