New technology for recyclingmaterials from oily cold rollingmill sludge

Oily cold rolling mill (CRM) sludge is one of metallurgical industry solid wastes. The recycle of these wastes can not only protect the environment but also permit their reutilization. In this research, a new process of “hydrometallurgical treatment + hydrothermal synthesis” was investigated for the combined recovery of iron and organic materials from oily CRM sludge. Hydrometallurgical treatment, mainly including acid leaching, centrifugal separation, neutralization reaction, oxidizing, and preparation of hydrothermal reaction precursor, was first utilized for processing the sludge. Then, micaceous iron oxide (MIO) pigment powders were prepared through hydrothermal reaction of the obtained precursor in alkaline media. The separated organic materials can be used for fuel or chemical feedstock. The quality of the prepared MIO pigments is in accordance with the standards of MIO pigments for paints (ISO 10601-2007). This clean, effective, and economical technology offers a new way to recycle oily CRM sludge.     

Recycle of valuable products from oily cold rolling mill sludge

Oily cold rolling mill (CRM) sludge contains lots of iron and alloying elements along with plenty of hazardous organic components, which makes it as an attractive secondary source and an environmental contaminant at the same time. The compound methods of “vacuum distillation + oxidizing roasting” and “vacuum distillation + hydrogen reduction” were employed for the recycle of oily cold rolling mill sludge. First, the sludge was dynamically vacuum distilled in a rotating furnace at 50 r/min and 600℃ for 3 h, which removed almost hazardous organic components, obtaining 89.2wt% ferrous resultant. Then, high purity ferric oxide powders (99.2wt%) and reduced iron powders (98.9wt%) were obtained when the distillation residues were oxidized and reduced, respectively. The distillation oil can be used for fuel or chemical feedstock, and the distillation gases can be collected and reused as a fuel.     

冷库废冷利用探析

论述了冷库融霜或融冰中排掉的融霜水或融冰水(“废冷”)以及合理回收利用的价值.用融霜水和融冰水作为过冷介质对进入冷凝器中的制冷剂过冷,升温后的水还可以作为冷却水系统的循环补充水,从而提高制冷系统的运行效率.对减少冷库能源消耗,降低运行成本具有一定的指导意义.     

Quantum encounters of the cold kind

Since the introduction of laser-cooling techniques for neutral atoms in the early 1980s, the study of collisional interactions between atoms and molecules has been extended to the regime of ultracold temperatures. With nanokelvin temperatures now attainable, our ability to probe the interactions, both experimentally and theoretically, has also progressed. Understanding of the subtle and often highly quantum-mechanical effects that are manifest at such low energies has advanced to the point where new precision measurements are matched by highly accurate theoretical calculations. Low-energy phenomena such as Bose-Einstein condensation and the photoassociation of atoms into bound molecules are now accurately described with no free parameters.     

Internal structure of a cold dark molecular cloud inferred from the extinction of background starlight

Stars and planets form within dark molecular clouds, but little is understood about the internal structure of these clouds, and consequently about the initial conditions that give rise to star and planet formation. The clouds are primarily composed of molecular hydrogen, which is virtually inaccessible to direct observation. But the clouds also contain dust, which is well mixed with the gas and which has well understood effects on the transmission of light. Here we use sensitive near-infrared measurements of the light from background stars as it is absorbed and scattered by trace amounts of dust to probe the internal structure of the dark cloud Barnard 68 with unprecedented detail. We find the cloud's density structure to be very well described by the equations for a pressure-confined, self-gravitating isothermal sphere that is critically stable according to the Bonnor-Ebert criteria. As a result we can precisely specify the physical conditions inside a dark cloud on the verge of collapse to form a star.     

品读《远离尘嚣》的三层意蕴

哈代的《远离尘嚣》描绘了远离闹市的威赛克斯乡村优美和谐的自然风光,古朴淳美的社会风俗,及其在资本主义侵蚀下所发生的微妙变化,叙述了女农场主芭思希芭及其女仆范妮与3个男人带有悲剧色彩的爱情故事,揭示了在命运之神操纵之下几个主要人物的悲剧性命运,具有文化、社会、哲学的丰富意蕴。     

旧沥青路面全深式冷再生基层材料力学性能

为研究应用旧沥青路面材料冷再生基层的混合料力学性能,回收原沥青路面面层旧料和基层旧料,制备沥青路面全深式冷再生基层材料,结合现场沥青面层及铣刨深度测试冷再生材料级配,测试冷再生基层材料的7 d无侧限抗压强度、90 d劈裂强度和90 d回弹模量,并观察其SEM微观形貌图。结果表明:水泥用量较少时7 d无侧限抗压强度、90 d劈裂强度和90 d回弹模量均随水泥剂量的增加快速增长,但是增长趋势逐渐变缓;较少的沥青旧料对再生基层力学性能是有利的,但是过多的沥青旧料则会产生较大的负面影响;当面层旧料的油石比较小时,水泥水化物取向结晶能刺破沥青膜层,直接与裹附在沥青内部的集料接触,形成较强的界面,这样能有效缓解沥青对强度的负面影响。进而建议低等级公路的中、轻型交通等级水泥剂量在5%~7%,其他类型公路则在提高水泥剂量的同时需要改善旧料级配;油石比小的旧沥青路面改造更适合推行全深式冷再生基层技术。     

冷辗机床进给系统的动态特性对冷辗精度的影响

进给系统对冷辗精度有很大的影响,主要在于冷辗过程是一动态的工作过程,该文在分析系统静、动态特性和工作状态的基础上,建立了简化模型,根据此模型定性分析了进给系统特性,并就其响应频率所造成的对冷辗精度的影响进行阐述,该文的分析方法对进给系统的优化设计有一定的参考价值.     

赤桉叶片的离体培养与植株再生

以无菌苗叶片为外植体进行了赤桉不定芽的诱导及植株再生。结果表明,在MS 0.8 mg/L BA 0.3 mg/L KT 0.05 mg/L NAA的培养基上,丛生芽诱导率为35.4%;附加0.8 mg/L BA 0.05 mg/L TDZ 0.1 mg/L NAA的MS培养基能促进赤桉不定芽的诱导,其诱导率达42.9%;暗培养10 d能促进不定芽的分化。当芽长至2~3 cm时,切下生长健壮的芽并接入生根培养基,生根率达100%,移栽成活率超过80%。