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A new Ruhrstahl–Heraeus (RH) equipment with a weir added to the vacuum chamber was designed to help improve refining efficiency of low-carbon steel production. The flow characteristics of the new RH equipment and a traditional RH equipment were evaluated and compared through water modeling experiments and an optimized calculation model. In the water experiments, the mixing time, the residence time and the circulation flow rates were measured, and the flow simulating molten steel in the vacuum was photographed. The results show that the decarburization efficiency in the new RH equipment is much improved. The mixing time is equal to or less than that of the latter when the gas flow rate is higher than 2.33 m3/h. The proportion of the piston flow increases by at least 40%, and the proportion of the well-mixed flow decreases from greater than 40% to less than 20%. The effective flow rate of the new RH equipment increases greatly in the piston flow zone and the total lag flow zone based on the residence time distribution experiment. In conclusion, when a weir is added to a RH vacuum chamber, the effective circulation flow increases significantly, and the decarburization rate KCof molten steel at low-carbon stage is improved.

It is of great importance to treat a bacterial-infected wound by a smart dressing capable of delivering antibiotics in a smart manner without causing drug resistance. The construction of smart release nanocontainers responsive to near-infrared (NIR) laser irradiation in an on-demand and stepwise way is a promising strategy for avoiding the emergence of multidrug-resistant bacteria. Here, we develop a hydrogel composite made of alginate and nanotubes with an efficient NIR-triggered release of rifampicin and outstanding antibacterial ability. This composite hydrogel is prepared through co-encapsulating antibacterial drug (rifampicin), NIR-absorbing dye (indocyanine green), and phase-change materials (a eutectic mixture of fatty acids) into halloysite nanotubes, followed by incorporation into alginate hydrogels, allowing the in-situ gelation at room temperature and maintaining the integrity of drug-loaded nanotubes. Among them, the eutectic mixture with a melting point of 39 °C serves as the biocompatible phase-change material to facilitate the NIR-triggered drug release. The resultant phase-change material gated-nanotubes exhibit a prominent photothermal efficiency with multistep drug release under laser irradiation. In an in vitroassay, composite hydrogel provides good antibacterial potency against Staphylococcus aureus,one of the most prevalent microorganisms of dangerous gas gangrene. A bacterial-infected rat full-thickness wound model demonstrates that the NIR-responsive composite hydrogel inhibits the bacteria colonization and suppresses the inflammatory response caused by bacteria, promoting angiogenesis and collagen deposition to accelerate wound regeneration. The NIR-responsive composite hydrogel has a great potential as an antibacterial wound dressing functionalized with controlled multistep treatment of the infected sites.

A variety of new N-(5-(benzofuranol-7-oxymethyl)-1,3,4-thiadiazol-2-yl)amide compounds (8a-i) were synthesized through four steps from benzofuranol as raw materials. The crystal structure of compound 8a(C17H21N3O3S, Mr=347.43) was measured by X-ray diffraction, which was classified as monoclinic system, Z= 4, V =1742.72(8) Å3, Dc=1.324 Mg/m3, F(000) = 736, S =1.03, µ = 0.21 mm−1, space group P21with a =9.9177(3), b =8.9519(2), c =19.8679(5) Å, the final R =0.035 and wR =0.105 for 3873 observed reflections (I> 2σ(I)).The X-ray structure presented N(3)–H(3)···N(2) and C(6)–H(6)···O(3) intermolecular hydrogen bonds, which acted as an important role in stabilizing the crystal structure. Additionally, preliminary biological assay on compound 8ashowed good fungicidal activity in vivo,with the inhibition of 75% against Pseudoperonospora cubensisat 200 mg/L.

The solidification process and microstructure of Al-7Si-0.3Mg alloy with different rare earth (RE) additions have been studied by using thermal analysis, optical microscopy (OM), scanning electron microscopy (SEM) and X-ray diffraction (XRD) analysis. The results showed that the addition of RE enhanced the liquidus temperature and decreased the growth temperature of eutectic Si, which lead to obvious increase in solidification interval of the studied alloy. In addition, the grain size of primary α-Al had no obvious change, and the mean area of eutectic Si particles decreased with increasing RE content to 1.6 wt.%. The RE-rich compounds with different compositions were obtained with increasing RE concentration in Al-7Si-0.3Mg alloys. The method of phase diagram calculation helps to clarify the formation and growth mechamism of different RE-rich phases during solidification.

The shrinkage porosity that was caused by the insufficient feeding during solidification, was a common defect in the semi-solid die casting process. This defect decreased significantly the mechanical properties of the casting. In order to avoid the shrinkage porosity in casting, the die design, slug preparation and die casting process were carefully considered. In this study, a designed mold was used to make the sequential solidification of the slug. The process parameters, including intensification pressure, die temperature and biscuit thickness of the casting, were studied to show their influence on shrinkage porosity defects. The experimental results show that the high intensification pressure, high die temperature and long biscuit can be beneficial to obtain castings with no shrinkage porosity.

Reported herein is the hydride transfer initiated redox-neutral cascade cyclizations of aurones, providing a variety of [6,5] spiro-heterocycles in satisfactory yields and good diastereoselectivities.

Described herein is an unprecedented N-alkylation-initiated redox-neutral [5 + 2] annulation of 3-alkylindoles with o-aminobenzaldehydes via a cascade N-alkylation/dehydration/[1,5]-hydride transfer/Friedel–Crafts alkylation sequence. A series of indole-1,2-fused 1,4-benzodiazepines are facilely constructed in moderate to good yields in one step. This protocol features excellent regioselectivity, metal-free conditions, high step economy, and wide substrate scope.

The redox-neutral cascade dearomatization of indoles with o-aminobenzaldehydes has been realized via the hydride transfer strategy, achieving the condition- and substrate-controlled divergent synthesis of tetrahydroquinoline-fused spiroindolenines. The integration of hydride transfer-involved C(sp3)–H functionalization with dearomatization provides a promising platform for the construction of structurally diverse molecules.

Liquid permeability of the mushy zone is important for porosity formation during the solidification process. In order to investigate the permeability of the mushy zone, an integrated model was developed by combining the phase field model and computational fluid dynamics (CFD) model. The three-dimensional multigrain dendrite morphology was obtained by using the phase field model. Subsequently, the computer-aided design (CAD) geometry and mesh were generated based on calculated dendrite morphologies. Finally, the permeability of the dendritic mushy zone was obtained by solving the Navier-Stokes and continuity equations in ANSYS Fluent software. As an example, the dendritic mushy zone permeability of Al-4.5wt%Cu alloy and its relationship with the solid fractions were studied in detail. The predicted permeability data can be input to the solidification model on a greater length scale for macro segregation and porosity simulations.

Microstructures with fine globular grains and refined eutectic structures are important to enhance the mechanical properties of A356 alloys processed by semi-solid and gravity die casting. Rare earth (RE) additions have been shown to be capable of refining both the α-Al particles as well as modify the eutectic phase of alloys. In semi-solid die casting, Al7Si0.3Mg alloys with RE concentrations (0, 0.1 and 0.4 wt.%) were used to prepare semi-solid slurries using the SEED (Swirling Enthalpy Equilibrium Device) method, and subsequently semi-solid die cast. The same compositions of alloys were also applied to gravity die casting. The microstructure and mechanical properties of castings in two processes have been characterized. Compared to the grains produced in gravity die casting, globular grains with small size (260 μm) in the semi-solid die casting significantly enhance the UTS and elongation of alloys. Although the size of grains had no change with increasing RE concentrations in alloys. The Al-Si eutectics were changed to refined morphology with the 0.1 wt.% RE addition, which enhanced the ductility of alloys in two processes. When increasing the RE addition to 0.4 wt.%, the RE-rich phases precipitated at grain boundaries, which decreased the UTS and elongation of alloys.

Minute amounts of tumor vasculature-targeted TNFα was reported to increase endothelial permeability, thereby accelerating drug penetration and increasing the therapeutic index of chemotherapeutic agents. This study aimed at assessing the synergistic anti-cancer effects of three chemotherapeutic drugs and tumor vasculature-targeted TNFα in a murine orthotopic colorectal cancer model. TNFα was firstly coupled with a vascular-homing peptide TCP-1 to form a TNFα derivative (TCP-1/TNFα). After pretreated with 1 ng TCP-1/TNFα, the three chemotherapeutic drugs exerted differential synergistic effects on anti-cancer actions and presented different intratumoral accumulation statuses. To further assess transvascular transport efficiency of these drugs, an in vitrosystem was carried out to mimic the endothelial cell monolayer. Results showed that 5-fluorouracil which exerted the best anti-cancer action and intratumoral accumulation status with preadministration of 1 ng TCP-1/TNFα had the highest transvascular transportation efficiency. This work would provide important information for designing clinical studies with vasculature-targeted TNFα in combination with chemotherapeutic drugs for optimal synergism.

Vitamin D has been widely used as a dietary supplement for the prevention and treatment of bone disorders. Epidemiological and preclinical studies demonstrated the anticancer action of vitamin D in a variety of cancers including those in the gastrointestinal (GI) tract. In these studies the inhibitory action of vitamin D on cancer stem cells (CSCs) has been a focus and is also an important subject to revolutionize the therapeutic potential of vitamin D on cancer treatment. Here, we summarize the involvement of CSC markers and factors and also their signaling pathways in the development of cancers in the esophagus, stomach, colon, pancreas and also liver. It is also evidenced that vitamin D could inhibit these markers and factors and their related signaling pathways to suppress tumor progression. All these information could provide new strategies in repurposing vitamin D as therapeutic agent to inhibit cancers in the GI tract.

The character of microstructure in the segregation of 82B wire with two different stelmor control cooling procedures and kinetics of eutectoid transformation of segregation through thermal simulation in the range of 400-600°C were researched. The longitudinal section segregation microstructure and composition were analyzed by OMSEMWDS. The thermal simulation results show that the length of martensite segregation bands is decreased holding 10-40s above 500°C, and martensite band in the core of wire where the content of Mn and Cr elements is higher than matrix because of segregation. Furthermore, Stelmor control cooling experiments in the high speed wire mill confirms that there is a critical temperature500°C to 82B wire above which the eutectoid transformation in the segregation is possible, and enough time above the critical temperature in the Stelmor control cooling lids is the key to optimizing procedure.

Highway route design indexes are the key factors which can determine the overall performance of highway. They affect not only the economy, safety, function of highway, but also affect the amount of CO2 emissions of highway. In order to find the most reasonable route design indexes, firstly, establish the function relationship between route design indexes and carbon emissions and cost-effectiveness of highway and social environment. Secondly, analyze action strategies of the highway construction main bodies and the social environment main bodies based on game theory. Thirdly, establish the complete information static game model, and solve to get the pure strategy Nash equilibrium in different circumstances. Establish a set of methods of evaluating highway route design indexes. Provide a scientific decision basis for highway construction departments.

The CO2 emissions of highway transportation industry are huge. There are many factors which are affecting highway carbon emission. To reduce vehicle emissions, and improve the design, construction, operation and management of highway, which was the main purpose of the study. The whole life cycle of highway was divided into construction stage and operation stage. Factors which affected carbon emissions of different highway stages were discussed, and they were artificial carbon emissions, energy consumption of machinery and equipment, building materials, pavement types, low carbon management, types and carbon emission coefficients, running speed, radius of curvature of horizontal curve, road roughness, gradient of longitudinal curve, traffic volumes, plant carbon sink. Put forward the highway carbon emissions accounting methods, and established the carbon accounting models. The research will be helpful to reduce carbon emissions of highway transportation industry.

The CO2 emissions of highway transportation industry are huge.  In order to study factors affecting carbon emissions of highway operation period, selected five primary route design indicators to analyze.  The five indicators were Speed, Gradient, Radius of Curvature, IRI, Traffic Volume and Green Belt.  Combined the existing Carbon Accounting Model and the Carbon Accounting Software of Highway Operation Period[4], which could calculate the equivalent carbon emissions.  By using Gray relational analysis method, calculated the relational degrees between route design indicators and carbon emissions of highway operation period.  At last, found that the most important factor affecting carbon emissions of highway operation period was average daily traffic volume.  The research will be helpful to discuss the carbon emissions of highway operation period in a targeted manner.

To provide DC power to auxiliary equipment for a certain type of aircraft, according to the actual need, small power two-way dc power supply is designed using current mode pulse width modulator UCC2800. This paper introduces the basic principle of UCC2800, and also introduces the design and realization process of the low-power dc power supply based on UCC2800.

Flywheel Energy Storage System (FESS) has become an important research field because of the energy problem. To solve the control of Permanent Magnet Synchronous Motor (PMSM) and Bi-directional power converter, both charging and discharging control strategiesthe Compound Control for charging and the Integrated Optimization Flux-Weak Control for discharging are proposed, together with the dual-loop control and simulation results. Based on these analysis and results, a high-power DSP-controlled experiment platform is set up to test the proposed strategies. Simulation and experiment results show that the FESS can run smoothly both under charging and discharging conditions so that both the strategies and the platform are effective.

Dynamic recrystallization (DRX) of ferrite in a low carbon steel with the (α+θ) duplex microstructures was investigated using hot compression tests in combination with SEM, TEM and EBSD, and the effect of the size of cementite particles was analyzed. The results indicated that during hot deformation of the low carbon steel DRX of ferrite took place and the increase in the average size of cementite particles was of benefit to DRX. The formation of DRX grains was attributed to particle stimulated nucleation (PSN), by the well development of the subgrain near cementite particles. At the beginning of hot deformation, DRX grains were mainly formed near cementite particles with the size of about 1μm or above. With the increase in the strain, such grains were also formed around pairs or groups of particles with the size of 0.5μm to 1μm.

Based on industrial silicon and carbon black as starting materials,β-SiC bonded SiC materials were prepared. The microstructure of such material and the silicon/carbon reaction were analyzed and investigated by XRD, SEM and other tools. The results indicate that the synthesis of β-SiC at 1400℃ can be achieved through gas-phase mass transfer, liquid dissolution as well as in-situ reaction. While gas-phase mass transfer is the dominant reaction during the sintering of the material, in which β-SiC exists mainly as nanowhisker. The formation of β-SiC nanowires is believed to be the mechanism of reaction sintering.

Different temperature rises during finishing rolling of T8 cord steel were obtained through normal procedure (process 1) and controlled cooling procedure (process 2), and its effects on the microstructure and the mechanical properties were studied. The microstructure of T8 cord steel obtained by process 1 consisted of clusters of coarser and inhomogeneity sorbite colonies, and that obtained by process 2 consisted of equiaxed and finer sorbite colonies, with the similar interlamellar spaces of sorbite cementite in the two microstructures. The results of tensile tests showed that the tensile strength of T8 cord steel obtained by process 2 was higher than that obtained by process1 by 20MPa, with higher reduction of area and tensile elongation. In addition, the tensile fracture of T8 cord steel obtained by process 1 consisted of a lot of lotus cleavage plane, while that of T8 cord steel obtained by process 2 mainly consisted of finer dimples. That indicated that the smaller temperature rise of process 2 during finishing rolling can improve the mechanical properties of T8 cord steel.

It has been shown that learning to rank approaches are capable of learning highly effective ranking functions. However, these approaches have mostly ignored the important issue of efficiency. Given that both efficiency and effectiveness are important for real search engines, models that are optimized for effectiveness may not meet the strict efficiency requirements necessary to deploy in a production environment. In this work, we present a unified framework for jointly optimizing effectiveness and efficiency. We propose new metrics that capture the tradeoff between these two competing forces and devise a strategy for automatically learning models that directly optimize the tradeoff metrics. Experiments indicate that models learned in this way provide a good balance between retrieval effectiveness and efficiency. With specific loss functions, learned models converge to familiar existing ones, which demonstrate the generality of our framework. Finally, we show that our approach naturally leads to a reduction in the variance of query execution times, which is important for query load balancing and user satisfaction.

Mechanical properties of a medium-carbon steel with the ultrafine (α+θ) microstructures obtained by hot deformation of undercooled austenite and annealing were investigated by tensile tests, in comparison with that of a eutectoid steel. The results indicated that in the case of hot deformation of undercooled austenite to strain of 1.61 at 650°C at 0.01s-1 and annealing at 650°C for 30min, the ultrafine (α+θ) microstructures consisting of ultrafine ferrite grains and dispersed cementite particles were similar in the medium-carbon steel and the eutectoid steel, but the mechanical properties of the eutectoid steel were better that maybe be attributed to the relatively coarser size and the higher amount of cementite particles. With the increase of temperature for hot deformation of undercooled austenite to 700°C, the ultrafine (α+θ) microstructure of the medium-carbon steel changed obviously with the presence of some spheroidized pearlite colonies, and demonstrated the best balance of strength and elongation, the yield strength of about 545MPa, the tensile strength of about 635MPa, and the total elongation of about 35%.

A novel thermomechanical process to manufacture hot-rolled transformation-induced plasticity (TRIP) steels was developed based on dynamic transformation of undercooled austenite (DTUA). Between DTUA and the isothermal bainitic treatment, only one-step controlled-cooling was required. The microstructure evolution of hot-rolled C-Mn-Si and C-Mn-Al-Si TRIP steels based on DTUA was investigated by hot uniaxial compression tests using a Gleeble1500 simulation test machine. The results indicated that during DTUA, the kinetics of ferrite formation was fast, the volume fraction of ferrite formed was determined by applied strain. In comparison with the process based on static transformation of austenite, a more uniform multiphase microstructure with fine ferrite grains was formed, the bainite packets were small and had relatively random orientations, the retained austenite distributed uniformly and had relatively high volume fraction. Hot-rolled TRIP steels based on DTUA demonstrated better mechanical properties, especially for C-Mn-Al-Si TRIP steel.

Microstructure evolution and mechanical properties of hypereutectoid steel with the microduplex (α+θ) structures formed by hot deformation of undercooled austenite were investigated by hot uniaxial compression tests in a Gleeble-1500 simulation test machine, and the effects of subsequent annealing and the addition of Al were analyzed. The results indicated that at the beginning of hot deformation of undercooled austenite the formation of proeutectoid cementite was retrained and only lamellar pearlite was produced. With further strain, dynamic spheroidization of pearlite took place, leading to the formation of microduplex (α+θ) structure consisting of ultrafine ferrite matrix and dispersed cementite particles. In comparison with the normal microstructure consisting of lamellar pearlite and proeutectoid cementite, the microduplex (α+θ) structure presented higher strengths with similar ductility. Subsequent annealing could make the microduplex (α+θ) structure more uniform, which demonstrated better balance between strength and ductility. The addition of Al is disadvantageous to the formation of microduplex (α+θ) structure, but can result in the further refinement. With the addition of Al, the strength of microduplex (α+θ) structure was improved and the ductility was not deteriorated markedly.

Dynamic recrystallization(DRX) of ferrite in low carbon steels was investigated by hot compression tests at temperatures of 550 to 700oC at strain rates of 0.001 to 10s-1. The results indicate that DRX of ferrite can occur in low carbon steels and lead to grain refinement. With increasing Zener-Hollomon parameter Z, its mechanism changes from discontinuous dynamic recrystallization to continuous dynamic recrystallization, the turning point is approximately at Z=1×1016s-1 for a low carbon steel with 0.171wt% C. The results also indicate that changing the minor constituents of the low carbon steel from pearlite colonies to fine cementite particles has an effect on promoting DRX of ferrite, and the increase of Mn content and the presence of tiny Nb precipitates have opposite effects respectively. However, all these changes are of benefit to the refinement of recrystallized grains.

The hot deformation behavior of a low carbon Nb-microalloyed steel is investigated by hot compression test in the ferrite phase region compared with a low carbon steel with similar compositions, and the effect of Nb on dynamic recrystallization of ferrite is analyzed. Results indicate that during hot deformation in the ferrite phase region, the effect of Nb solely depends on the size of NbC precipitates. Tiny particles which average size is about 7.5nm have a retarding effect on dynamic recrystallization process of ferrite, on the contrary, coarser particles which average size is about 30.6nm have a promoting effect and are of benefit to the refinement of recrystallized grains.

Oxalierpenes A and B (1and 2), two unusual indole-diterpenoid derivatives, were obtained from the marine-derived fungus Penicillium oxalicum. The absolute configurations of 1and 2were elucidated by calculated TDDFT ECD and DP4plus methods. Oxalierpene A (1) represents the first indole-diterpenoid derivative with a five-membered ring of 4-hydroxy-5,5-dimethyldihydrofuran-3-one as a side chain. Oxalierpene B (2) has a unique 6/5/6/5/5/6/6/5/5 ring system. Compounds 1and 2showed antiviral activity against the H1N1 virus and respiratory syncytial virus (RSV), with IC50values ranging from 2.8 to 9.4 μM.