干燥转轮除湿器的新数学模型与RDCS程序

发展了干燥转轮除湿器的数学模型。控制方程中除考虑周向对流项｛平和上士及非定常项上Ｌ和运二外，还增加了吸附剂中的热扩散项＼共和外关及质量扩散项于共和才知。新编ＲＤＣＳ程序，采用松驰迭代法求解离散方程组。空间差分涉及对流和扩散两种不同的传热、传质形式，对流项采用一阶迎风差分格式，扩散项采用中心差分格式。时间差分可根据需要采用显格式、全隐格式或其它半隐格式。将ＲＤＣＳ与国外除湿器的数值计算结果和为数不多的实验数据作了比较。结果表明，ＲＤＣＳ的精度更高，适用范围更广。新建立的数学模型能更全面地反映干燥转轮中经历的传热、传质过程的物理本质。     

新型海水淡化装置中的模糊控制

介绍一种新型海水淡化系统.针对复杂的具有不确定数学模型的试验装置,采用模糊控制理论设计了一套双层多变量控制器,将其用于温度控制,模糊控制算法全部采用硬件运算处理,经现场运行与检测,该控制系统运算快、精确度高、可靠性好,满足设计要求.     

Erratum to: Effects of redox-active interlayer anions on the oxygen evolution reactivity of NiFe-layered double hydroxide nanosheets

Nano Research - The labels in Fig. 8 in the original version of this article were unfortunately misplaced. The corrected figure is as follow.     

Effect of NaOH Concentration and Adding Sequences on Structural and Magnetic Properties of Ni<Subscript>0.4</Subscript>Co<Subscript>0.6</Subscript>Fe<Subscript>2</Subscript>O<Subscript>4</Subscript> Nanopowders Prepared Via Co-precipitation Route

Ni_0.4Co_0.6Fe₂O₄ nanopowders were prepared via the co-precipitation route followed by annealing treatment. The structural and magnetic properties of the as-synthesized samples were determined by XRD, FT-IR, TG-DSC, and PPMS measurements, respectively. The XRD patterns indicated a single-phase cubic spinel structure for all the Ni-Co ferrite samples, regardless of adding sequences of the reactants or NaOH concentration. The analysis of the XRD patterns revealed that the enhancement in lattice constant with increasing NaOH concentration is related to the prevention of oxidization of Co²⁺ ions in the Ni-Co ferrite lattice. The FT-IR spectra indicated that samples prepared in the B process have fewer impurities than those prepared in the A process. The enhancement in saturation magnetization with the increase in sodium hydroxide concentration could be attributed to the strengthening of super-exchange interaction between A and B sublattices, due to replacements of Co³⁺ ions (magnetic moment of 0 μ _B) by Co²⁺ ions (magnetic moment of 3 μ _B) at B sublattices. The obvious increase in the coercivity field with the increase in concentration of NaOH solutions can be interpreted in terms of enhancement of magneto-crystalline anisotropy that originated from gradual substitutions of Co³⁺ ions with Co²⁺ ions at the octahedral sites.     

形状记忆合金驱动器驱动方式研究

七文阐述了 Ｓ Ｍ Ａ 驱动器的驱动原理,分析了 Ｓ Ｍ Ａ 的性能和不同驱动方式对 Ｓ Ｍ Ａ 驱动器输出性能的影响。文章认为, Ｓ Ｍ Ａ 的相变温度范围越小,高低温时性能相差越大, Ｓ Ｍ Ａ 双程驱动器的输出性能越好;差动式 Ｓ Ｍ Ａ 双程驱动器与偏动式 Ｓ Ｍ Ａ 双程驱动器相比,前者更容易获得较大的输出力和输出位移,但后者较容易控制,响应速度较快。     

高层建筑采光中庭高空现浇屋架的施工

为了解决高层建筑采光中庭悬空100m以上的屋架施工困难,采用了高空钢操作平台方案。介绍平台钢粱缩小跨度的措施,平台构件制作和安装顺序,叙述了通过平台屋架模板支撑、混凝土浇筑的方法及采取的安全措施,达到了顺利施工和节约成本的目的。     

Trade-Off Between Efficiency and Stability of CsPbBr3 Perovskite Quantum Dot-Based Light-Emitting Diodes by Optimized Passivation Ligands for Br/Pb

Although significant progress has been made in improving the external quantum efficiencies (EQEs) of perovskite quantum dot (QD) light-emitting diodes (QLEDs), understanding the degradation mechanism and enhancing stability remain a challenge. Herein,  increasing the content of Br-based passivation ligands is shown to enhance the EQE up to 16.1% by reducing the defects of CsPbBr₃ QDs in a Br-rich environment. However, the operational lifetimes of perovskite QLEDs gradually decrease with the increase of halide content, owing to the intensified ion migration under continuous electric field confirmed by the current behavior of QLEDs and time-of-flight secondary-ion mass spectrometry. Furthermore, a thorough analysis of the relationship between electricity and luminance of QLEDs suggests that a small amount of residue oleic acid ligands could weaken ion migration. Accordingly, a halide- and acid-hybrid (HAH) co-passivation strategy is proposed to optimize the content of Br- and acid-based ligands, and achieve a maximum EQE of 18.6% and an operational lifetime (T₅₀, extrapolated) of 213 h for CsPbBr₃ QLEDs. This approach for passivating QDs combines the high efficiency of Br-based ligands with the improved stability of acid-based ligands. The study elucidates the correlation between ligands and device performance, highlighting the significance of two or even multiple ligands for efficient and stable perovskite QLEDs.     

基于FFRLS辨识优化橡胶挤出机Smith-模糊PID温度控制系统

为了精准辨识橡胶挤出机Smith-模糊PID温度控制系统中的Smith预估模型,更好地实现温控系统滞后补偿控制,借助MATLAB软件搭建Smith-模糊PID温度控制系统,为避免产生“数据饱和”的现象,采用带遗忘因子递推最小二乘(FFRLS)辨识算法对Smith预估器的新、老数据给出不同的辨识信度进行辨识,并将FFRLS辨识优化前后的系统控制效果进行对比。实验结果表明：在不同程度干扰作用下,FFRLS辨识后的Smith预估控制器具有更好的延迟矫正能力与参数变化辨识能力;采用FFRLS辨识的橡胶挤出机Smith-模糊PID温控系统鲁棒性更强,可以在一定程度上提升温控系统的控制精度。     

Scale effects and scaling-up by geometric-optical model

By considering the constitution relationship between stress and strain in viscous EDA media in the domain of frequency, seismic wave equations in the media in the domain of time and space are established. The anelastic effects induced by cracks or fractures are shown by the third derivatives of displacement components with respect to time in the equations. After solving the equations for the seismic propagation of plane waves, seismic velocity, attenuation and quality factor ( Q value) are obtained, and their azimuthal anisotropy in the dry cracked and water saturated cracked EDA media are studied. The results show that, seismic velocity, attenuation, quality factor ( Q value), especially attenuation or quality factor ratio of 2 kinds of qS wave can be used to indicate the existence of oriented cracks and material contents in the crack. Meanwhile, elasticity is predominant at low frequency, and anelasticity is significant at high frequency.     

喷水工艺对木质素胶黏剂刨花板性能影响的研究

就板坯制备工艺对采用木质素胶黏剂制备刨花板进行试验研究,通过设计正交试验,获取和分析所制备刨花板的物理力学性能,探讨制板工艺过程对木质素胶黏剂刨花板性能的影响.试验结果表明,制板过程中,采用喷水工艺对木质素胶黏剂刨花板的静曲强度和弹性模量影响最大,对24 h吸水厚度膨胀率影响次之,对内结合强度影响较小;随着喷水量的增大...