Influence of Temperature on the Bacterial Community in Substrate and Extracellular Enzyme Activity of Auricularia cornea

( Xiaoping Zhang ),( Bo Zhang ),( Renyun Miao ),( Jie Zhou ),( Lei Ye ),( Dinghong Jia ),( Weihong Peng ),( Lijuan Yan ),( Xiaoping Zhang ),( Wei Tan ),( Xiaolin Li ) 한국균학회 2018 Mycobiology Vol.46 No.3

Temperature is an important environmental factor that can greatly influence the cultivation of Auricularia cornea. In this study, lignin peroxidase, laccase, manganese peroxidase, and cellulose in A. cornea fruiting bodies were tested under five different temperatures (20℃, 25℃, 30℃, 35℃, and 40℃) in three different culture periods (10 days, 20 days and 30 days). In addition, the V4 region of bacterial 16S rRNA genes in the substrate of A. cornea cultivated for 30 days at different temperatures were sequenced using next-generation sequencing technology to explore the structure and diversity of bacterial communities in the substrate. Temperature and culture days had a significant effect on the activities of the four enzymes, and changes in activity were not synchronized with changes in temperature and culture days. Overall, we obtained 487,694 sequences from 15 samples and assigned them to 16 bacterial phyla. Bacterial community composition and structure in the substrate changed when the temperature was above 35℃. The relative abundances of some bacteria were significantly affected by temperature. A total of 35 genera at five temperatures in the substrate were correlated, and 41 functional pathways were predicted in the study. Bacterial genes associated with the membrane transport pathway had the highest average abundance (16.16%), and this increased at 35℃ and 40℃. Generally, different temperatures had impacts on the physiological activity of A. cornea and the bacterial community in the substrate; therefore, the data presented herein should facilitate cultivation of A. cornea.

VALVE MOTION CHARACTERISTICS AND APPLICATION ON ENGINE BASED ON A NEW VARIABLE VALVE ACTUATION SYSTEM

You Zhou,Weihong Zhou,Fangxi Xie,Yu Liu,Xiaoping Li,Xun Gong 한국자동차공학회 2023 International journal of automotive technology Vol.24 No.1

A new mechanical-hydraulic variable valve actuation (VVA) system was developed and a thin-wall orifice velocity control system were analyzed. Meanwhile, influence of speed, needle valve overflow area, oil temperature and oil supply pressure on valve motion characteristics were explored, as well as the VVA system have been applied on a single-cylinder engine preliminary. By the VVA system, valve lifts can be adjusted from maximum of 8.7 mm to fully closing. Valve seating velocity decreased with orifice diameter reducing. Seating velocity can be maintained below 0.5 m/s with 0.8 mm diameter of thin-wall orifice and 3 mm check valve moving distance. Besides that, velocity control system also can help improve the coefficient of cyclic variation of maximum valve lift. Except for the needle valve closing state, valve lift decreased with oil temperature increasing and operating speed reducing under the same needle valve state. Oil supply pressure hardly had no influence on valve lifts, but delayed valve opening timing with pressure decreasing. Thin-wall orifice seating velocity control system was not sensitive to variable oil temperature and supply pressure. Compared with conventional engine, adjusting intake valve by VVA system under un-throttle internal EGR strategy, can improve BSFC and NOX emissions significantly about 13.8 % and 19.8 % on 6 bar IMEP.

Cold-induced ginsenosides accumulation is associated with the alteration in DNA methylation and relative gene expression in perennial American ginseng (Panax quinquefolius L.) along with its plant growth and development process

Mengzhen Hao,Yuhang Zhou,Jinhui Zhou,Min Zhang,Kangjiao Yan,Sheng Jiang,Wenshui Wang,Xiaoping Peng,San Zhou 고려인삼학회 2020 Journal of Ginseng Research Vol.44 No.5

Background: Ginsenosides accumulation responses to temperature are critical to quality formation in cold-dependent American ginseng. However, the studies on cold requirement mechanism relevant to ginsenosides have been limited in this species. Methods: Two experiments were carried out: one was a multivariate linear regression analysis between the ginsenosides accumulation and the environmental conditions of American ginseng from different sites of China and the other was a synchronous determination of ginsenosides accumulation, overall DNA methylation, and relative gene expression in different tissues during different developmental stages of American ginseng after experiencing different cold exposure duration treatments. Results: Results showed that the variation of the contents as well as the yields of total and individual ginsenosides Rg1, Re, and Rb1 in the roots were closely associated with environmental temperature conditions which implied that the cold environment plays a decisive role in the ginsenoside accumulation of American ginseng. Further results showed that there is a cyclically reversible dynamism between methylation and demethylation of DNA in the perennial American ginseng in response to temperature seasonality. And sufficient cold exposure duration in winter caused sufficient DNA demethylation in tender leaves in early spring and then accompanied the high expression of flowering gene PqFT in flowering stages and ginsenosides biosynthesis gene PqDDS in green berry stages successively, and finally, maximum ginsenosides accumulation occurred in the roots of American ginseng. Conclusion: We, therefore, hypothesized that cold-induced DNA methylation changes might regulate relative gene expression involving both plant development and plant secondary metabolites in such cold-dependent perennial plant species.

Novel Collaborative Design Method for Lightweight Optimization Design of Vehicle Load-Bearing Parts

Zhou Dashuang,Kang Zhengyang,Su Xiaoping 한국자동차공학회 2023 International journal of automotive technology Vol.24 No.5

The design of new energy vehicle load-bearing structural components using traditional experience may lead to low material utilization efficiency. This makes it difficult to reduce the quality, or material shortage, which will increase the number of product design iterations and design cycle. Fortunately, the increasingly mature structural topology optimization technology can effectively solve this problem, and can provide a structural basic feature with high material utilization efficiency for parts according to the structural optimization objective. In addition, the rapid development of special casting technology makes it easier to process parts with complex shapes. Herein, a collaborative design method combining structural topology optimization design, material lightweight design and squeeze casting process was proposed to realize the lightweight of new energy vehicle load-bearing structural parts more effectively. The collaborative design method was applied to the steering knuckle design of a vehicle, and the results show that the method has a significant lightweight effect and can obtain the aluminum alloy steering knuckle with better quality.

Composite of Indium and Polysorbate 20 as Inhibitor for Zinc Corrosion in Alkaline Solution

Xiaoping Li,Man Liang,Hebing Zhou,Qiming Huang,Dongsheng Lv,Weishan Li 대한화학회 2012 Bulletin of the Korean Chemical Society Vol.33 No.5

The combined use of indium and polysorbate 20 (Tween 20) was considered as a new inhibition technique for zinc corrosion. Zn and Zn-In alloy coatings were prepared by electrodeposition and their morphology and composition were characterized by scanning electron microscopy (SEM) and inductively coupled plasma atomic emission spectrometry (ICP-AES). The corrosion inhibition effect of indium and Tween 20 on zinc was investigated by polarization curves and electrochemical impedance spectroscopy (EIS). The corrosion inhibition efficiencies obtained from Tafel and EIS analyses are well in agreement. Zinc corrosion can be inhibited to some extent by the individual use of indium and Tween 20 and higher corrosion inhibition efficiency can be obtained by the combined use of indium and Tween 20.

Fetal ECG Extraction by Combining Single-Channel SVD and Cyclostationarity-Based Blind Source Separation

XiaoPing Zeng,ShaoHua Li,GuoJun Li,Yu Zhou,DaiHui Mo 보안공학연구지원센터(IJSIP) 2013 International Journal of Signal Processing, Image Vol.6 No.4

Temporal Autocorrelation Properties of Three Dimensional Vehicle-to -Vehicle Channels in the Presence of Moving Scatterers

Xiaoping Zeng,Yu Zhou,Xin Jian,Jie Huang,Jing Li 보안공학연구지원센터 2015 International Journal of Future Generation Communi Vol.8 No.2

This paper derives the analytical expression of the temporal autocorrelation function (ACF) of the non-stationary three dimensional (3D) multipath scattering channels, in which scatterers move with constant velocities in random directions around transceivers. The analytical expression involves high dimensional integration within finite interval, thus a methodology based on ray-tracing is proposed to carry out its numerical solution. The analytical expression and the corresponding ray-tracing based model serve as the canonical forms for the correlation analysis of non-stationary 3D multipath scattering channels, which include two special cases: two dimensional (2D) multipath scattering and stationary multipath scattering. Numerical results show that: in case of non-stationary 3D multipath scattering, with the increase of the velocity and the density of scatterers, the temporal ACF would attenuate more rapidly. These results would allow engineers more appropriate determination on coherence time and coherence bandwidth for vehicle-to-vehicle communication systems.

Composite of Indium and Polysorbate 20 as Inhibitor for Zinc Corrosion in Alkaline Solution

Li, Xiaoping,Liang, Man,Zhou, Hebing,Huang, Qiming,Lv, Dongsheng,Li, Weishan Korean Chemical Society 2012 Bulletin of the Korean Chemical Society Vol.33 No.5

The combined use of indium and polysorbate 20 (Tween 20) was considered as a new inhibition technique for zinc corrosion. Zn and Zn-In alloy coatings were prepared by electrodeposition and their morphology and composition were characterized by scanning electron microscopy (SEM) and inductively coupled plasma atomic emission spectrometry (ICP-AES). The corrosion inhibition effect of indium and Tween 20 on zinc was investigated by polarization curves and electrochemical impedance spectroscopy (EIS). The corrosion inhibition efficiencies obtained from Tafel and EIS analyses are well in agreement. Zinc corrosion can be inhibited to some extent by the individual use of indium and Tween 20 and higher corrosion inhibition efficiency can be obtained by the combined use of indium and Tween 20.

Biosorption of uranium by Bacillus sp.FB12 isolated from the vicinity of a power plant

Xu, Xiaoping,He, Shengbin,Wang, Zhenshou,Zhou, Yang,Lan, Jing Techno-Press 2013 Advances in environmental research Vol.2 No.3

Biosorption represents a technological innovation as well as a cost effective excellent remediation technology for cleaning up radionuclides from aqueous environment. In the present study, a bacteria strain FB12 with high adsorption rate of uranium ion was isolated from the vicinity of the nuclear power plant. It was tentatively identified as Bacillus sp.FB12 according to the 16S rDNA sequencing. Efforts were made to further improve the adsorption rate and genetic stability by UV irradiation and UV-LiCl cooperative mutagenesis. The improved strain named Bacillus sp.UV32 obtains excellent genetic stability and a high adsorption rate of 95.9%. The adsorption of uranium U (VI) by Bacillus sp.UV32 from aqueous solution was examined as a function of metal ion concentration, cell concentration, adsorption time, pH, temperature, and the presence of some foreign ions. The adsorption process of U (VI) was found to follow the pseudo-second-order kinetic equation. The adsorption isotherm study indicated that it preferably followed the Langmuir adsorption isotherm. The thermodynamic parameters values calculated clearly indicated that the adsorption process was feasible, spontaneous and endothermic in nature. These properties show that Bacillus sp.UV32 has potential application in the removal of uranium (VI) from the radioactive wastewater.

Time-dependent behaviour of interactive marine and terrestrial deposit clay

Chen, Xiaoping,Luo, Qingzi,Zhou, Qiujuan Techno-Press 2014 Geomechanics & engineering Vol.7 No.3

A series of one-dimensional consolidation tests and triaxial creep tests were performed on Nansha clays, which are interactive marine and terrestrial deposits, to investigate their time-dependent behaviour. Based on experimental observations of oedometer tests, normally consolidated soils exhibit larger secondary compression than overconsolidated soils; the secondary consolidation coefficient ($C_{\alpha}$) generally gets the maximum value as load approaches the preconsolidation pressure. The postsurcharge secondary consolidation coefficient ($C_{\alpha}$') is significantly less than $C_{\alpha}$. The observed secondary compression behaviour is consistent with the $C_{\alpha}/C_c$ concept, regardless of surcharging. The $C_{\alpha}/C_c$ ratio is a constant that is applicable to the recompression and compression ranges. Compared with the stage-loading test, the single-loading oedometer test can evaluate the entire process of secondary compression; $C_{\alpha}$ varies significantly with time and is larger than the $C_{\alpha}$ obtained from the stage-loading test. Based on experimental observations of triaxial creep tests, the creep for the drained state differs from the creep for the undrained state. The behaviour can be predicted by a characteristic relationship among axial strain rate, deviator stress level and time.