Electric fields induced by ring and pin electrodes in electrostatic charged powder sprayingtechnique are analysed. The fundamental formulae to deseribe these fields have been built up. Theseformulae could be used to d...Electric fields induced by ring and pin electrodes in electrostatic charged powder sprayingtechnique are analysed. The fundamental formulae to deseribe these fields have been built up. Theseformulae could be used to design electrostatic charged podwer spraying system. The chargingeffectiveness of ring and pin electrode is experimentally investigated and compared each other. Theperformance of ring electrode is better than that of pin electrode.展开更多
高压静电场(high voltage electrostatic field,HVEF)技术涉及物理、化学、电子、生物等多个学科,具备能耗低、效率高、清洁环保等优点,是未来消毒杀菌和低碳环保的重要发展方向,并逐渐成为农业领域新兴研究热点。综述了近20年来HVEF在...高压静电场(high voltage electrostatic field,HVEF)技术涉及物理、化学、电子、生物等多个学科,具备能耗低、效率高、清洁环保等优点,是未来消毒杀菌和低碳环保的重要发展方向,并逐渐成为农业领域新兴研究热点。综述了近20年来HVEF在灭菌和食品保鲜等方面的主要研究进展及其在水产领域的应用,旨在促进其在水产品处理以及水产育种等方面的应用。展开更多
Myoglobin has important biological functions in storing and transporting small diatomic molecules in human body. Two possible orientations of carbon monoxide （CO） in the heme distal pocket （named as BI and B2 state...Myoglobin has important biological functions in storing and transporting small diatomic molecules in human body. Two possible orientations of carbon monoxide （CO） in the heme distal pocket （named as BI and B2 states） of myoglobin have been experimentally indicated. In this study, ab initio quantum mechanics/molecular mechanics （QM/MM） molecular dynamics simulation of CO in myoglobin was carried out to investigate the two possible B states. Our results demonstrate that the B1 and B2 states correspond to Fe... CO （with carbon atom closer to iron center of heme） and Fe... OC （with oxygen atom closer to Fe）, by comparing with the experimental infrared spectrum. QM electrostatic polarization effect on CO brought from the protein and solvent environment is the main driving force, which anchors CO in two distinctive orientations and hinders its rotation. The calculated vibrational frequency shift between the state B1 and B2 is 13.1 cm-1, which is in good agreement with experimental value of 11.5 cm-1. This study also shows that the electric field produced by the solvent plays an important role in assisting protein functions by exerting directional electric field at the active site of the protein, From residue-based electric field decomposition, several residues were found to have most contributions to the total electric field at the CO center, including a few charged residues and three adjacent uncharged polar residues （namely, HIS64, ILE107, and PHE43）. This study provides new physical insights on rational design of enzyme with higher electric field at the active site.展开更多
为探讨不同高压电场处理对大肠杆菌的诱变效应及诱变效应的比较,本试验以野生型大肠杆菌K12W3110为研究对象,采用3种不同的电场处理:高压静电场(HVEF)、高压变频电场(HVFEF)和高压芒刺电场(HVPEF),考察菌体的存活率、突变率,绘制各高压...为探讨不同高压电场处理对大肠杆菌的诱变效应及诱变效应的比较,本试验以野生型大肠杆菌K12W3110为研究对象,采用3种不同的电场处理:高压静电场(HVEF)、高压变频电场(HVFEF)和高压芒刺电场(HVPEF),考察菌体的存活率、突变率,绘制各高压电场处理在显著剂量处理条件下的突变谱,并进行比较分析。结果表明,3种电场在不同场强处理下,突变率和存活率都呈振荡趋势,低场强时先是抑制作用,随着场强增加逐渐变成刺激效应,其中表现最明显的是高压芒刺电场处理。高压芒刺电场在1 k V·cm^(-1)场强下处理大肠杆菌时,突变率最高为对照组的12倍;而高压变频电场在4 k Hz·4k V·cm^(-1)场强下处理时,突变率最高为对照组的7.36倍;高压静电场在场强为4 k V·cm^(-1)处理时,突变率最高为对照组的5.47倍。因此,相对于对照组,3种高压电场的突变效应均有提高,其中突变效应最明显的是高压芒刺电场,其次是高压变频电场,最后是高压静电场。本研究初步探索了不同电场处理对大肠杆菌诱变效应的影响,为大肠杆菌的电场诱变处理选择提供了理论参考依据。展开更多
文摘Electric fields induced by ring and pin electrodes in electrostatic charged powder sprayingtechnique are analysed. The fundamental formulae to deseribe these fields have been built up. Theseformulae could be used to design electrostatic charged podwer spraying system. The chargingeffectiveness of ring and pin electrode is experimentally investigated and compared each other. Theperformance of ring electrode is better than that of pin electrode.
文摘高压静电场(high voltage electrostatic field,HVEF)技术涉及物理、化学、电子、生物等多个学科,具备能耗低、效率高、清洁环保等优点,是未来消毒杀菌和低碳环保的重要发展方向,并逐渐成为农业领域新兴研究热点。综述了近20年来HVEF在灭菌和食品保鲜等方面的主要研究进展及其在水产领域的应用,旨在促进其在水产品处理以及水产育种等方面的应用。
文摘Myoglobin has important biological functions in storing and transporting small diatomic molecules in human body. Two possible orientations of carbon monoxide （CO） in the heme distal pocket （named as BI and B2 states） of myoglobin have been experimentally indicated. In this study, ab initio quantum mechanics/molecular mechanics （QM/MM） molecular dynamics simulation of CO in myoglobin was carried out to investigate the two possible B states. Our results demonstrate that the B1 and B2 states correspond to Fe... CO （with carbon atom closer to iron center of heme） and Fe... OC （with oxygen atom closer to Fe）, by comparing with the experimental infrared spectrum. QM electrostatic polarization effect on CO brought from the protein and solvent environment is the main driving force, which anchors CO in two distinctive orientations and hinders its rotation. The calculated vibrational frequency shift between the state B1 and B2 is 13.1 cm-1, which is in good agreement with experimental value of 11.5 cm-1. This study also shows that the electric field produced by the solvent plays an important role in assisting protein functions by exerting directional electric field at the active site of the protein, From residue-based electric field decomposition, several residues were found to have most contributions to the total electric field at the CO center, including a few charged residues and three adjacent uncharged polar residues （namely, HIS64, ILE107, and PHE43）. This study provides new physical insights on rational design of enzyme with higher electric field at the active site.
文摘为探讨不同高压电场处理对大肠杆菌的诱变效应及诱变效应的比较,本试验以野生型大肠杆菌K12W3110为研究对象,采用3种不同的电场处理:高压静电场(HVEF)、高压变频电场(HVFEF)和高压芒刺电场(HVPEF),考察菌体的存活率、突变率,绘制各高压电场处理在显著剂量处理条件下的突变谱,并进行比较分析。结果表明,3种电场在不同场强处理下,突变率和存活率都呈振荡趋势,低场强时先是抑制作用,随着场强增加逐渐变成刺激效应,其中表现最明显的是高压芒刺电场处理。高压芒刺电场在1 k V·cm^(-1)场强下处理大肠杆菌时,突变率最高为对照组的12倍;而高压变频电场在4 k Hz·4k V·cm^(-1)场强下处理时,突变率最高为对照组的7.36倍;高压静电场在场强为4 k V·cm^(-1)处理时,突变率最高为对照组的5.47倍。因此,相对于对照组,3种高压电场的突变效应均有提高,其中突变效应最明显的是高压芒刺电场,其次是高压变频电场,最后是高压静电场。本研究初步探索了不同电场处理对大肠杆菌诱变效应的影响,为大肠杆菌的电场诱变处理选择提供了理论参考依据。
