Poly brominated biphenyl(PBBs) and poly brominated diphenyl ether(PBDEs) in polymers of electrotechnical products have been extracted with toluene and analyzed by gas chromatography-mass spectrometry (GC-MS).The resul...Poly brominated biphenyl(PBBs) and poly brominated diphenyl ether(PBDEs) in polymers of electrotechnical products have been extracted with toluene and analyzed by gas chromatography-mass spectrometry (GC-MS).The result has more credibility when the nature of the sample was determined by retention time and the proportion of characteristic ions.PBBs and PBDEs were quantified by internal standard method and 2′,3,3′,4,4′,5,5′,6,6′-decachlorobiphenyl was used as internal standard.The GC-MS experimental results show,that the average spiked recoveries ranged from 81% to 110%,that the relative standard deviations(RSD) ranged from 1.54% to 8.65%.The research results also showed that the method presented simplicity-operating,excellent linearity and reproducibility.展开更多
Two momentous events will take place in China in October. The second largest economy in the world is set to celebrate its 70th anniversary of its founding on October 1, remembering lessons learned from the past, and p...Two momentous events will take place in China in October. The second largest economy in the world is set to celebrate its 70th anniversary of its founding on October 1, remembering lessons learned from the past, and presenting remarkable achievements and future outlooks. Later in the same month, the IEC General Meeting, themed on MBetter Quality, Better Life — Reliability, Safety, Efficiency>,, will be held in Shanghai, a financial hub and metropolis in China. It will gather more than 2,500 attendees from some 80 countries and regions to discuss standards issues in the electrotechnical area.展开更多
This article highlights the importance of complementing classes through educational videos, especially in disciplines exclusively with lectures. This proposition is exemplified through basic concepts in alternating cu...This article highlights the importance of complementing classes through educational videos, especially in disciplines exclusively with lectures. This proposition is exemplified through basic concepts in alternating current for both single-phase and three-phase circuits, which are critical in the formation of electrical engineers, mechanics, chemists, etc. The main objective of conducting educational videos is to make learning more attractive and stimulate interest in acquiring the knowledge of certain topics, given their importance in professional life in different engineering areas. The videos, filmed in laboratory and of short duration, aim to complement and consolidate the content taught in the classroom lectures.展开更多
Chinese electrotechnical industry includes power generation equipment, power transmission and distribution equipment, multi-purpose equipment, and basic electrical material. The industry has 46 national technical ... Chinese electrotechnical industry includes power generation equipment, power transmission and distribution equipment, multi-purpose equipment, and basic electrical material. The industry has 46 national technical committees (TC) and sub-committees (SC), which mirrors to 70 TCs and SCs of International Electrotechnical Commission (IEC). During the past five years, leaded by Standardization Administration of China (SAC),China Electrical Equipment Industry Association (CEEIA) obtained many great achievements in promoting participation of international standardization activities by improving unified management and concentrating industrial strength:……展开更多
文摘Poly brominated biphenyl(PBBs) and poly brominated diphenyl ether(PBDEs) in polymers of electrotechnical products have been extracted with toluene and analyzed by gas chromatography-mass spectrometry (GC-MS).The result has more credibility when the nature of the sample was determined by retention time and the proportion of characteristic ions.PBBs and PBDEs were quantified by internal standard method and 2′,3,3′,4,4′,5,5′,6,6′-decachlorobiphenyl was used as internal standard.The GC-MS experimental results show,that the average spiked recoveries ranged from 81% to 110%,that the relative standard deviations(RSD) ranged from 1.54% to 8.65%.The research results also showed that the method presented simplicity-operating,excellent linearity and reproducibility.
文摘Two momentous events will take place in China in October. The second largest economy in the world is set to celebrate its 70th anniversary of its founding on October 1, remembering lessons learned from the past, and presenting remarkable achievements and future outlooks. Later in the same month, the IEC General Meeting, themed on MBetter Quality, Better Life — Reliability, Safety, Efficiency>,, will be held in Shanghai, a financial hub and metropolis in China. It will gather more than 2,500 attendees from some 80 countries and regions to discuss standards issues in the electrotechnical area.
文摘This article highlights the importance of complementing classes through educational videos, especially in disciplines exclusively with lectures. This proposition is exemplified through basic concepts in alternating current for both single-phase and three-phase circuits, which are critical in the formation of electrical engineers, mechanics, chemists, etc. The main objective of conducting educational videos is to make learning more attractive and stimulate interest in acquiring the knowledge of certain topics, given their importance in professional life in different engineering areas. The videos, filmed in laboratory and of short duration, aim to complement and consolidate the content taught in the classroom lectures.
文摘 Chinese electrotechnical industry includes power generation equipment, power transmission and distribution equipment, multi-purpose equipment, and basic electrical material. The industry has 46 national technical committees (TC) and sub-committees (SC), which mirrors to 70 TCs and SCs of International Electrotechnical Commission (IEC). During the past five years, leaded by Standardization Administration of China (SAC),China Electrical Equipment Industry Association (CEEIA) obtained many great achievements in promoting participation of international standardization activities by improving unified management and concentrating industrial strength:……
