数字技术环境下景观规划设计教学改革与实践

设计创新能力培养已成为21世纪风景园林学规划设计教学核心，在此背景下，由知识传输导向的教学模式正逐步转变为由设计与科研并肩引领知识增长的教学模式，数字化景观规划设计教学体系与方法成为当代风景园林教育亟待充实并应用的重要内容。立足风景园林教学前沿，基于对当代风景园林规划设计教育的系统把握，以东南大学风景园林专业教学实践为例，提出整合数字景观技术平台，构建“浸入式”数字技术教学环境，实现数字平台与教学体系的协同创新；继而针对传统教学方法局限，利用数字化教学平台进行“耦合教学法”创新实践，加强实证性知识体系集成融合，实现风景园林规划设计课程教学模式的系统探索与实践。     

Electromagnetic coupling field strengthening of WC-TiC-Co cermet tools

This work proposes the application of pulsed electromagnetic coupling field processing (EMCFP) to enhance the lifetime and cutting performance of WC-15TiC-6Co cermet tool for the first time. Firstly, the developed electromagnetic field coupling equipment is introduced, the treatment process is analyzed, and the magnetization characteristics of WC-15TiC-6Co cermet tool are evaluated. Secondly, the strengthening effect of the EMCFP treatment is demonstrated by mechanical properties testing and cutting experiments, which reveal that the optimally treated tools exhibit a fracture toughness increased by 18%, an average cutting temperature decreased by 10%, and a friction coefficient for the rank face decreased by 7.9%. Collectively, these enhancements result in a tool lifetime increased by a factor of 1.92 relative to the lifetime of untreated tools. In addition, the results of simulation demonstrate that the simultaneously pulsed magnetic and electric fields contribute toward greater magnetic flux density and current density on the surface of the WC-15TiC-6Co cermet tool than would be obtained from the magnetic and electric fields alone.     

Room-temperature multiferroic characteristics and unique vortex domain structures of h-Yb1−xInxFeO3 solid solutions

Hexagonal rare-earth ferrites (h-RFeO₃) have attracted much scientific attention due to their room-temperature multiferroicity. However, it is still a hard job to obtain h-RFeO₃ bulk materials because of the meta-stability of such hexagonal phase, and the evaluation of room-temperature ferroelectric and magnetoelectric characteristics in such materials is also a challengeable issue. In the present work, Yb_1−xIn_xFeO₃ ceramics with the stable hexagonal structure were obtained by introducing chemical pressure, where the unique ferroelectric domain structures of sixfold vortex combined with tenfold vortex with a typical size of ~400 nm were determined. Symmetry of the present system evolved from centrosymmetric orthorhombic Pbnm (x = 0–0.4) to non-centrosymmetric hexagonal P6₃cm (x = 0.5 and 0.6) with a ferroelectric polarization up to 3.2 μC/cm², and finally to centrosymmetric hexagonal P6₃/mmc (x = 0.7 and 0.8). The Curie point decreased monotonically from 723 K to a temperature below room temperature with increasing x, and the antiferromagnetic phase transition above room temperature was determined for all compositions. Meanwhile, a large linear magnetoelectric coefficient (α_ME) up to 0.96 mV/cm Oe was obtained at room temperature, and this indicated the great application potential for magnetoelectric devices.     

导管架平台上部组块双船拆除

为研究复杂海域环境中海洋平台双船拆除方法的安全性与可操作性,采用水动力数值计算与水池模型试验相结合的方法进行研究。将双船水动力耦合计算与水池模型试验进行对比,在相对理想海况下,结合与实际工况接近的规则波作用,进行驳船水动力性能变化与运动响应的幅值分析。在受力分析方面,对甲板耦合装置进行改良设计,对比试验数据与数值计算数据,得到受力在合理范围内的结论。研究内容为实际施工的合理性提出一定的指导性意见。     

Double Mutant Cycles as a Tool to Address Folding,Binding, and Allostery

Quantitative measurement of intramolecular and intermolecular interactions in protein structure is an elusive task, not easy to address experimentally. The phenomenon denoted ‘energetic coupling’ describes short- and long-range interactions between two residues in a protein system. A powerful method to identify and quantitatively characterize long-range interactions and allosteric networks in proteins or protein–ligand complexes is called double-mutant cycles analysis. In this review we describe the thermodynamic principles and basic equations that underlie the double mutant cycle methodology, its fields of application and latest employments, and caveats and pitfalls that the experimentalists must consider. In particular, we show how double mutant cycles can be a powerful tool to investigate allosteric mechanisms in protein binding reactions as well as elusive states in protein folding pathways.     

台头焦煤7202运输顺槽弱胶结围岩支护技术研究

台头焦煤7202运输顺槽进过程中存在弱胶结膨胀软岩地层,支护难度大。为解决该问题,进行耦合模拟研究,结果表明,普通锚杆支护在90 d左右时会出现巷道垮塌现象,结合顶板离层仪观测数据,表明模拟结果真实可靠。对巷道支护优化方案,采用工字钢结合管棚锚喷技术,实施完成进行效果考察,考察结果显示优化方案有效解决了弱胶结软岩支护难度大的问题。     

Sand-ejecting fire extinguisher parameter sensitivity analysis based on DOE and CFD-DEM coupling simulations

To get more accurate quantitative impact effects of selective parameters of the sand-ejecting fire extinguisher on the scattering results by the CFD-DEM coupling method, orthogonal experimental design, analysis of range and variance, full factorial design and the OFAT design were used in this paper. The single impact effects and mixed impact effects of blade number, blade incidence and sand mass flow on scattering vertical distance and inclination were analysed and concluded, as well as the details of the sand distribution. The results show that only the sand mass flow has the dominating influence on the vertical distance, while all three factors have no significant influence on the scattering inclination. The larger the sand mass flow is, the more obvious influence of air resistance and airflow from the outlet of the scattering unit can be shown, and the scattering bifurcation phenomenon can be displayed more obviously.     

Synthesis and characterization of cross-linked polymer with sulfonylimide group via UV-radical polymerization for PEMFC

The purpose of this research is to synthesized a new monomer and polymer containing fluorosulfonyl imide acid. A series of polymer electrolyte membranes are prepared via UV-curing technique with polyethylene glycol dimethacrylate (PEGDMA) and the methacryloyl fluorosulfonylimide (MAFSI), which is synthesized by methacrylamide (MAA) and fluorosulfonyl isocyanate (FSO₂NCO). The MAFSI monomer and the polymer electrolyte (PMFP) are successfully synthesized and confirmed the structure by ¹H NMR and FT-IR. The membranes exhibit high proton conductivity from 79.14 to 110.87 mS/cm, low water uptake from 8.74 to 28.57%, and low dimensional expansion from 6.5 to 30.8% in spite of high IEC values from 3.97 to 5.71 meq./g. In addition, the membranes exhibit good thermal stability up to 150 °C temperatures and the surface morphology of the membrane observed good phase separation between MAFSI and ethylene glycol segments.     

Influence of milling time on the structural and exchange bias of CoO and Co–Co oxide nanocomposite systems

This study aimed to investigate the effect of milling time on the structural and exchange bias properties of two exchange-coupled nanocomposite systems that were prepared by mechanical milling. The first system consists of an antiferromagnet (CoO), named CoO-series and the second one consists of a mixture of a ferromagnet with an antiferromagnet (10 wt% Co + CoO), called MIX-series and both systems were milled for various times. Upon field cooling, going through low temperature (5 K), hysteresis loop shifts, coercivity enhancements, and saturation magnetization reductions were observed as milling time increases. Noticeable enhancements of exchange bias (270 Oe) and coercivity (1039 Oe) of the CoO-series after 10 h of milling, in comparison with those of unmilled ones (16 Oe) and (136 Oe) respectively, showed that the main structural changes occurred at the first milling hours. Introduction of large structural defects, the formation of cobalt and crystallite size reduction, ensuing from milling, can be the causes of an increase in exchange bias and coercivity. On the other hand, ferromagnet-antiferromagnet exchange coupling induces by milling is another origin for exchange bias. The results show that ferromagnet-antiferromagnet ratio and/or crystallite sizes play key roles in exchange bias enhancement. So that milled CoO-series with lower Co content in comparison with that of MIX-series and finer crystallites have considerable higher exchange bias.     

Surface modification of TiO2 particles with 12-hydroxy stearic acid and the effect of particle size on the mechanical and thermal properties of thermoplastic polyurethane urea elastomers

The efficient surface modification of titanium dioxide (TiO₂) particles with different sizes was first carried out with “water only method” (Appl. Surf. Sci. 2018, 447, 664–672) developed in our group using 12-hydroxy stearic acid (12-HSA) as the modifier. The 12-HSA-modified TiO₂ particles with different sizes were then used to explore their effect on the mechanical and thermal properties of a thermoplastic polyurethane urea (TPUU) elastomer with superior mechanical and thermal properties produced newly in our lab using nonsymmetric alicyclic diisocyanate and diamine. Orthogonal experimental results showed that the order of impact of each factor on the modification efficiency of TiO₂ particles was: Temperature > time > modifier content. It was found that, in the nanometer (≤100 nm) range, smaller particles were more helpful to enhance the tensile strength of the TPUU elastomer, while larger ones to increase more significantly the elongation at break. Besides, the TiO₂/polyurethane urea nanocomposites exhibited much better thermomechanical performance than the pristine TPUU elastomer, and the thermomechanical performance of the nanocomposites increased with decreasing particle size.