带压堵漏作业防护探索与研究

本文分析了泄露现场的化学和物理危害因素及由此导致的各种后果,而且针对泄露事故对作业人员不同部位的伤害提出了相对应的个人防护用品,同时提供了与之相对应的国家行业标准.     

2号高炉高冶强下的指标优化措施

在高冶强的生产状态下,高炉如何优化各项技术经济指标,降低其成本,从而提高产品竞争力,是现代高炉操作者积极探索的问题。梅钢2号高炉通过精料、优化操作、改进工艺措施等的实施,实现了高炉高冶强下的指标优化。     

Antireflection and band gap extension effects of ZnO nanocrystalline films grown on ITO-coated glasses by low temperature process

Zinc oxide (ZnO) nanocrystalline films coated on indium tin oxides (ITO, 90:10 wt%) glasses were prepared by low temperature process. The thin films were composed of uniform nanoparticles with average diameter around 8.4 nm. All samples exhibited excellent optical antireflective phenomena, and the maximum transmission reached 92.8% for the sample spin coated at 1500 rpm at 453 nm, improved by 21.5%. The antireflective results were explained by the coherence theory. And the antireflective effects were induced by the ITO and ZnO films. The calculated thicknesses of the ZnO films agreed well with the experimental results. The theoretical calculated band gap from the average diameter of ZnO nanoparticles was also well consistent with the experimental ones obtained from the optical transmission spectra. This result was promising for applications in organic solar cells.     

Ultraviolet-visible and surface-enhanced Raman scattering spectroscopy studies on self-assembled films of ruthenium phthalocyanine on organic monolayer-modified silver substrates

A self-assembled film of ruthenium phthalocyanine (RuPc) fabricated on a silver substrate pre-modified with a monolayer of 4-mercaptopyridine (PySH) or 1,4-bis[2-(4-pyridyl)ethenyl]-benzene (BPENB) was studied by ultraviolet-visible (UV-Vis) and surface enhanced Raman scattering (SERS) spectroscopy. PySH or BPENB was used as a ligand to link RuPc since they not only modify the silver substrate, but also deliver a pyridyl group pointing out from the silver surface. Therefore, we can explore the relationship between the structure and orientation of metallophthalocyanine and the substrate modified by the two kinds of organic-monolayers with the different conjugates and molecular lengths. UV-Vis bands due to the organic-monolayer (PySH or BPENB) modified silver films shift to longer wavelengths and a new band arising from the metallophthlocyanine appears, suggesting the binding of RuPc to PySH/BPENB, as well as the interaction between the marcocycle of RuPc and the ring of PySH/BPENB. Vibrational bands arising from both the RuPc and PySH/BPENB moieties appear clearly in the SERS spectra of the RuPc-PySH/BPENB composite films, indicating that RuPc is successfully assembled on the top of PySH/BPENB film. The shifts and relative intensity changes of bands due to PySH or BPENB in the SERS spectra imply the binding of the metallophthalocyanine to the pyridyl group in the composite films. Furthermore, the comparison of the SERS spectra revealed that the orientations of PySH and BPENB in the two kinds of composite films are different; the BPENB moiety in the RuPc-BPENB composite film is more perpendicular to the silver surface compared with the PySH moiety in the RuPc-PySH composite film.     

往复副螺棱高度对单螺杆挤出机内混合行为的影响

建立了带有扰动副螺棱的单螺杆均化段数学模型,探讨了不同副螺棱高度对混合的影响。将有限体积方法与叠加网格技术相结合,得到了螺槽内牛顿流体三维等温周期性速度场。采用4阶Runge-Kutta方法进行流体前锋追踪计算,得到了粒子群及示踪剂界面混合行为。Poincaré截面揭示了混沌混合在螺槽横截面内呈现"8"字形带状分布,内外分别被准周期运动区域填充。副螺棱高度越大,混沌混合区域所覆盖的尺度越大,混合能力越好。     

Truly Concomitant and Independently Expressed Short‐ and Long‐Term Plasticity in a Bi2O2Se‐Based Three‐Terminal Memristor

Concomitance of diverse synaptic plasticity across different timescales produces complex cognitive processes. To achieve comparable cognitive complexity in memristive neuromorphic systems, devices that are capable of emulating short‐term (STP) and long‐term plasticity (LTP) concomitantly are essential. In existing memristors, however, STP and LTP can only be induced selectively because of the inability to be decoupled using different loci and mechanisms. In this work, the first demonstration of truly concomitant STP and LTP is reported in a three‐terminal memristor that uses independent physical phenomena to represent each form of plasticity. The emerging layered material Bi₂O₂Se is used for memristors for the first time, opening up the prospects for ultrathin, high‐speed, and low‐power neuromorphic devices. The concerted action of STP and LTP allows full‐range modulation of the transient synaptic efficacy, from depression to facilitation, by stimulus frequency or intensity, providing a versatile device platform for neuromorphic function implementation. A heuristic recurrent neural circuitry model is developed to simulate the intricate “sleep–wake cycle autoregulation” process, in which the concomitance of STP and LTP is posited as a key factor in enabling this neural homeostasis. This work sheds new light on the development of generic memristor platforms for highly dynamic neuromorphic computing.     

Theoretical analysis of long-lived radioactive waste in pressurized water reactor

Background The accelerator-driven subcritical transmuta-tion system(ADS)is an advanced technology for the harmless disposal of nuclear waste.A theoretical analy...     

Numerical Investigations of Film Cooling Characteristics of Interrupted Slot and Trench Holes on a Vane Endwall

This paper describes film cooling characteristics of the novel combined configuration employing interrupted slot and trench holes on a vane endwall.Interrupted ...     

M23C6 precipitation and Si segregation promoted by deep cryogenic treatment aggravating pitting corrosion of supermartensitic stainless steel

The microstructure evolution and the pitting corrosion resistance of a supermartensitic stainless steel after deep cryogenic treatment process were clarified th...