作者机构：
[Liu, Jianfang; Wei, Lei; Duan, Haitao; Jin, Yongliang; Liu, Lian; Sun, Xianming; Jia, Dan; Chen, Song; Li, Jian] Wuhan Res Inst Mat Protect, State Key Lab Special Surface Protect Mat & Appli, Wuhan 430030, Peoples R China.;[Liu, Jianfang] Wuhan Polytech Univ, Coll Biol & Pharmaceut Engn, Wuhan 430023, Peoples R China.;[Sun, Xianming] Wuhan Inst Technol, Sch Mat Sci & Engn, Wuhan 430073, Peoples R China.
通讯机构：
[Li, Jian] W;Wuhan Res Inst Mat Protect, State Key Lab Special Surface Protect Mat & Appli, Wuhan 430030, Peoples R China.
关键词：
motor oil;oil condition evaluation;on-board diagnostic system
摘要：
The condition of the motor oil in civilian cars is difficult to monitor; hence, we propose a method to evaluate the degree of degradation of motor oil using an on-board diagnostic (OBD) system. Three civilian cars and four motor oils (containing mineral oils and synthetic oils) were subjected to five groups of road tests under urban traffic and high-way conditions. The operation information, oil service time, mileage, engine operation time, idle time of the engine, and number of start-ups of the engine were obtained using the proposed OBD system. Physiochemical properties and changes in the components of motor oils during road tests were analyzed in laboratory. The theoretical model of the comprehensive indicators of driving parameters and oil properties were established. The proposed method was successfully applied to different cars, motor oils, and operating conditions in road tests. All the theoretical models had high accuracy and precision. Herein, we provide a method to monitor the oil condition with real-time driving parameters and provide a reference for end users to change their motor oil reasonably.
摘要：
In this study, a multi-phenol antioxidant 2,4,6-tris(3,5-di-tert-butyl-4-hydroxyphenylthio)-1,3,5-triazine (THA) was synthesized. The thermal stability of THA and its oxidation resistance in triisodecyl trimellitate (TDTM) ester oil were evaluated compared with several commercial phenol antioxidants. Further investigations on the oxidation resistance and tribological performance of THA with dinonyl diphenylamine (Am) and ZDDP composites were conducted to determine the additive compatibility in TDTM. The results indicate that the THA possesses higher thermal stability and more effectiveness of oxidation resistance than the commercial phenol antioxidants. The synergistic anti-oxidative effect is confirmed for the THA/Am mixtures in TDTM ester oil. However, the addition of THA alone or THA/Am mixtures shows no improvement for the tribological performance of TDTM. Excitingly, the THA/Am/ZDDP composite additives not only have the superior oxidation resistance, but exhibit the effective friction and wear reductions. It suggests the excellent compatibility of the synthesized THA antioxidant with Am and ZDDP additives in TDTM ester oil.
期刊：
PROCEEDINGS OF THE INSTITUTION OF MECHANICAL ENGINEERS PART J-JOURNAL OF ENGINEERING TRIBOLOGY,2019年233(2):281-288 ISSN：1350-6501
通讯作者：
Li, Jian
作者机构：
[Liu, Jianfang; Wei, Lei; Duan, Haitao; Jin, Yongliang; Jia, Dan; Chen, Song; Qian, Xuzheng; Li, Jian] Wuhan Res Inst Mat Protect, State Key Lab Special Surface Protect Mat & Appli, Wuhan 430030, Hubei, Peoples R China.;[Liu, Jianfang] Wuhan Polytech Univ, Coll Biol & Pharmaceut Engn, Wuhan, Hubei, Peoples R China.
通讯机构：
[Li, Jian] W;Wuhan Res Inst Mat Protect, State Key Lab Special Surface Protect Mat & Appli, Wuhan 430030, Hubei, Peoples R China.
关键词：
Motor oil;oil drain interval;driving parameters;grey relational analysis;on-board diagnostic
摘要：
Although the reason is not clear, mileage is commonly recommended as an indicator to evaluate the oil drain interval of a car. This paper tries to investigate whether the mileage is the most suitable indicator to evaluate the oil drain interval based on scientific experiments and data analysis method. Three civilian cars and motor oils (contained mineral oil, semisynthetic oil, and synthetic oil) were subjected to road tests under urban traffic condition. The real-time driving parameters comprising speed, mileage, idle time, engine operation time, and number of starts were obtained by on-board diagnostic system. Synchronous oil samples were collected about every 30 days. The physicochemical properties and component changes of experimental oils were analyzed in laboratory. The effects of driving parameters on oil properties were studied with the improved grey relational analysis method. The results show that the influencing factors of driving parameters on motor oil degradation were different in different experimental cars. The influence of mileage on oil degradation was not obvious. The idle time of engine, engine operation time, and number of starts were the three most significantly influential factors on oil deterioration after comprehensive analysis of the three experimental cars.
摘要：
GroEL, a member of the Hsp60 class molecular chaperones, has been extensively studied by general molecular biological method not only on its ATPase activities but also on refolding mechanism. Here, a C80 isothermal calorimeter was applied to understand the molecular mechanism of GroEL-assisted refolding. The power-time curves were obtained from different reaction systems, and the integral heat was calculated and analyzed. The ATPase activity of HSP60 was proven to be very stable at high temperature and had a high temperature dependence. In ATP hydrolysis experiments, we found that ATP hydrolysis catalyzed by GroEL was an exothermic reaction, in which divalent cations especially magnesium cation played an important role. And the ATP concentration also influences the ATP hydrolysis rate. Moreover, GroEL can assist in refolding thermodenatured xylanase with the presence of ATP and co-chaperone GroES, and the refolding process was demonstrated to be endothermic reaction, indicating that non-native proteins interacted with hydrophobic apical domains of GroEL, mainly hydrophobic interaction. The thermodynamic parameters presented in this study illustrated the work mechanism of GroEL by microcalorimetry and have important implications for further study of other interaction mechanism.
摘要：
Maintaining an appropriate concentration of dissolved oxygen in aqueous solution is critical for efficient operation of a bioreactor, requiring sophisticated engineering design and a system of regulation to maximize oxygen transfer from the injected air bubbles to the cells. Bacterial hemoglobins are oxygen-binding proteins that transfer oxygen from the environment to metabolic processes and allow bacteria to grow even under microaerophilic conditions. To improve the oxygen utilization efficiency of cells and overcome the oxygen shortage in bioreactors, the gene coding for the Campylobacter jejuni single domain hemoglobin (CHb) gene was artificially synthesized and functionally expressed under the control of inducible expression promoters P-T7 and P-vgh in Escherichia coli. The effects of the recombinants P-T7-CHb and P-vgh-CHb on cell growth were evaluated in aerobic shake flasks, anaerobic capped bottles and a 5-L bioreactor, and a pronounced improvement in cell biomass was observed for CHb-expressing cells. To determine the growth curves, CHb gene expression, and CHb oxygen-binding capacity of specific recombinants with different promoters, we determined the time course of CHb gene expression in the two recombinants by semi-quantitative RT-PCR and CO differential spectrum assays. Based on the growth patterns of the two recombinants in the bioreactor, we proposed different recombinant types with optimal performance under specific culture conditions.
摘要：
SaPIN2a, the proteinase inhibitor of nightshade (Solanum americanum), has been proposed to regulate proteolysis in phloem development. In this study, we expressed and characterized recombinant SaPIN2a in Escherichia coli. Purified recombinant SaPIN2a (rSaPIN2a) had a strong inhibitory effect on serine proteinase chymotrypsin (IC50 36.1 nmol/L), but its inhibitory activities toward trypsin (IC50 398.6 nmol/L) and especially toward subtilisin (IC50 5004 nmol/L) were low. It did not inhibit cysteine proteinase papain and aspartic proteinase cathepsin D. rSaPIN2a was a competitive inhibitor of trypsin, and a noncompetitive inhibitor of chymotrypsin and subtilisin.
摘要：
The contents of three main functional components including amino acids, microelements and polysaccharides were determined in submerged-fermentation mycelium and compared with data of fruit body in Grifola frondosa. The results showed that the contents of three main functional components in mycelium were higher than or as same as the fruit body. This indicated that submerged-fermentation mycelium was not only better in output and period than traditional culture method, but also better in nutrient components than fruit body. So the process of submerged-fermentation has very bright future in mycelium production of Grifola frondosa.
摘要：
In this paper, the influence of different strains and mediums on the yield of submerged-fermentation mycelium of Grifola frondosa was studied. Five strains of Grifola frondosa, including Gr1, Gr2, Gr3, Gr4 and Gr5, were submerged-fermentation cultured and the growing situation of mycelium was measured and analyzed. The results showed that the growth of Gr1 and Gr5 were better than other 3 strains and corn powder medium was more useful to the growth of Grifola frondosa than PDA medium and basic medium.
