Hydrodynamics performance and tray efficiency analysis of the novel vertical spray packing tray

Column setup has been widely utilized in the petroleum and chemistry industries. However, with the fast progress of industries and the increasingly serious energy shortage, designing a new column setup with better performance and higher capacity becomes more urgent. In order to improve column's capacity and expand operating condition, a new type of column tray named novel vertical spray packing(NVSP) tray was designed and experimented. The performances of the novel tray, including pressure drop, weeping, entrainment and tray efficiency, were tested in a plexiglass column. In addition, performances of the novel tray were compared with that of the sieve tray and the Glitsch V1 valve tray. Based on the experiment data, the mathematical correlations of pressure drop, weeping and entrainment for the novel tray were established by regression analysis method. A fundamental model of dry pressure drop of the novel tray was promoted at the form of sum mode. The results indicate that the novel tray has wider operating condition and better performance.

Hydrodynamics and mass transfer performance analysis of flow-guided trapezoid spray packing tray

Distillation is the most common separation technology utilized in the petroleum and chemistry industries.Due to the wide usage of the distillation column,even a small improvement in performance may result in significant energy cost savings.Aiming to improve the hydrodynamics and mass transfer performance,the flow-guided trapezoid spray-packing tray(FTS-PT)was designed by combining flow-guided holes and trapezoidal caps with structured packing.And the experimental measurements of the FTSPT,including pressure drop,clear liquid height,weeping,entrainment,and tray efficiency,were conducted in a 500 mm diameter plexiglass column with the air-water-oxygen system.Moreover,the performance of the FTS-PT was compared with that of new vertical sieve tray(New VST)and F1 valve tray.The results show that FTS-PT has a significant advantage in pressure drop,entrainment,and capacity.Furthermore,the calculation model of the pressure drop was derived and used for the FTS-PT with a relative deviation of less than 5%.

新型导向立体板填复合塔板的研究与工业应用

为了实现大通量、高效率的目的,本文根据复合塔板的设计思想,开发设计了新型导向立体板填复合塔板(Novel FVPT).在一个直径为500 mm的有机玻璃塔内,使用空气-水(富氧水)物系对该塔板进行冷模实验.实验内容包括清液层高度、干板压降、湿板压降、雾沫夹带、漏液以及传质效率,研究其流体力学性能和传质效率随着气液相负荷的变化规律.本文还根据压降产生原理,结合影响塔板压降的因素,推导出了新型导向立体板填复合塔板干板压降的理论模型.此外,将新型导向立体板填复合塔板在化工生产中进行实践应用,扩大了工业产量,提高了分离效率,为企业和社会带来了经济效益和环境效益.

Effect of defects on the electronic structure of a PbI2/MoS2 van der Waals heterostructure: A first-principles study

PbI2/MoS2,as a typical van der Waals(vdW)heterostructure,has attracted intensive attention owing to its remarkable electronic and optoelectronic properties.In this work,the effect of defects on the electronic structures of a PbI2/MoS2 heterointerface has been systematically investigated.The manner in which the defects modulate the band structure of PbI2/MoS2,including the band gap,band edge,band alignment,and defect energy-level density within the band gap is discussed herein.It is shown that sulfur defects tune the band gaps,iodine defects shift the positions of the band edge and Fermi level,and lead defects realize the conversions between the straddling-gap band alignment and valence-band-aligned gap,thus enhancing the light-absorption ability of the material.

Nanoprobes in biomedical detection

Environmental problems caused by the development of nanotechnology have threatened human health. Investigating the biomedical effects of nanomaterials can help to solve these environmental safety issues. In studies on the biomedical effects of nanomaterials, several types of novel nanoscale probes that allow reliable, sensitive, accurate and rapid biomedical detection have emerged. We summarize recent developments in three categories of these nanoprobes, including noble metal nanocluster probes, carbon-based nanostructured probes, and unnatural amino acid-based probes. Besides reviewing the utility of different nanoprobes in cell imaging and protein detection, we also discuss the molecular mechanism of nanoprobe detection. Perspectives of novel nanoprobe design based on molecular details of biomedical detection are presented.

Targeted peptide-Au cluster binds to epidermal growth factor receptor (EGFR) in both active and inactive states： a clue for cancer inhibition through dual pathways

The epidermal growth factor receptor （EGFR） has become an important target protein in anticancer drug development. Meanwhile, peptide-Au cluster has been proposed as potential targeted nano-drug assembled by targeting peptide. Here, we designed and synthesized a novel peptide-Au cluster as AuloPeptides to target to EGFR. We found AumPeptides could target to the natural binding sites of all EGFRs at mem- brane in both active and inactive states by molecular simulations. Its targeted ability was further verified by the co-localization and blocking experiments. We also study the configuration modifications of both active and inactive EGFRs after binding by AumPeptides. For active EGFR, the absorbed AuloPeptide5 might replace the natural ligand in EGFR endocytosis process. Then, the peptide-Au cluster in endochylema could inhibit the cancer relating enzyme activity including thioredoxin reductasel （TrxR1） and induce the oxidative stress mediated apoptosis in tumor cells. For inactive EGFR, it was retained in inactive state by Au10 Peptides binding to inhibit dimerization of EGFR for anticancer. Both pathways might be applied in anticancer drug development based on the theoretical and experimental study here.