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Metabolic energy variation of yeast affects its antioxidant properties in beer brewing
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作者 Jinjing Wang Xuerong Fu +4 位作者 Mengqi Li Feiyun Zheng Chengtuo Niu Chunfeng Liu Qi Li 《Systems Microbiology and Biomanufacturing》 2021年第3期311-322,共12页
Oxidation destroys the flavor and freshness of the beer,and yeast with improved antioxidant activity would benefit the flavor stability of the beer.The aim of this work was to study the antioxidant networks of lager y... Oxidation destroys the flavor and freshness of the beer,and yeast with improved antioxidant activity would benefit the flavor stability of the beer.The aim of this work was to study the antioxidant networks of lager yeast for brewing industry.Through transcriptome and metabolome analysis,we were able to map changes in anti-oxidant pathways and transcription of genes in lager yeast.Results suggested that metabolic energy variation in yeast might be the main reason for the improved anti-oxidant capacity.Lower metabolic rate kept the yeast at relatively lower respiratory status at the end of fermentation,thereby prolonging the lifespan and potentially supporting its usage in serial fermentations.Up-regulation of mannose synthesis and hexose transport strengthened the cell structure,which may have contributed to the anti-oxidant capacity of yeast.A deeper understanding of the globally regulation pattern of anti-oxidation in lager yeast is expected to support the design of strain development strategies for improved anti-oxidant capacity of yeast for fermentation industry. 展开更多
关键词 Lager yeast ANTI-OXIDATION Metabolic energy variation ROBUSTNESS
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Effect of Variation of the Coefficient of Friction on the Temperature at the Level of the Fault Lips
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作者 Francis Olivier Djiogang Fidèle Koumetio +2 位作者 David Yemele Guy Pascal Konga Guillaume L. Ymeli 《Open Journal of Earthquake Research》 2022年第3期45-72,共28页
Earth’s crust is an anisotropic and purely heterogeneous medium, which is justified by existence of different discontinuities;our study aims to show the effect of the variation of coefficient of friction on the evolu... Earth’s crust is an anisotropic and purely heterogeneous medium, which is justified by existence of different discontinuities;our study aims to show the effect of the variation of coefficient of friction on the evolution of temperature and its impact on seismic forecasting. In this work, we are model in 2D the variation of thermal energy and temperature produced by friction at the level of fault lip as function of depth of the seismic focus and at different value of time. Earthquakes are born when the energy accumulated by friction at the level of fault is suddenly released causing damage, sometimes noticeable on the surface of earth (macroseisms), and sometimes not at all noticeable on the surface of earth (microseisms), then energy which occurs before is important to forecasting earthquake. Assuming that coefficient of friction is variable, our results have enabled us to highlight the fact that, the greater the coefficient of friction, more the temperature increases, although the temperature profile increase over time but not linearly reflecting the presence of different asperities and discontinuities zone;slip generated at the level of fault occur a variation of temperature on specific points called roughness in common agreement with the literature. A large part of energy produced by friction is dissipated in heat causing a local increases in temperature which a very short duration and called flash contact temperature, and that despite the fact that the temperature evolved in time and space, it all converged towards a perfectly distinguishable fixed point. 展开更多
关键词 EARTHQUAKES Coefficient of Friction Nucleation Phase Temperature variation energy variation Asperity Point
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Sustainability of Wind Energy under Changing Wind Regimes—A Case Study 被引量:2
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作者 Nicole Mölders Dinah Khordakova +1 位作者 Ralph Dlugi Gerhard Kramm 《Atmospheric and Climate Sciences》 2016年第2期158-173,共16页
A method was introduced to assess the sustainability of energy production over the lifetime (~20 y) of wind turbines. Community Earth System Model simulations were downscaled for the tourist seasons (mid-May to mid-Se... A method was introduced to assess the sustainability of energy production over the lifetime (~20 y) of wind turbines. Community Earth System Model simulations were downscaled for the tourist seasons (mid-May to mid-September) of 2006 to 2012 (CESM-P1) and 2026 to 2032 (CESM-P2) to obtain a reference and projected wind-speed climatology, respectively. The wind speeds served to calculate the potential power output and capacity factors of seven turbine types. CESM-P1 wind-speed climatology, power output, and capacity factors were compared to those derived from wind speeds obtained by numerical weather forecasts for reference to known standard to wind-farm managers. Juneau, Alaska served as a virtual testbed as this region is known to experience changes in wind speeds in response to the Pacific Decadal Oscillation. CESM-P2 suggested about 2% decrease for wind speeds between the speeds at cut-in and rated power, and about 8% - 10% decrease in potential wind-power output. This means that in regions of decadal climate variations, the sustainability of wind-energy production should be part of the decision-making process. The study demonstrated that using mean values of wind-speeds can provide qualitative knowledge about decreases/increases in potential energy production, but not about the magnitude. Using the total individual wind-speed data of all seasons provided the same amount of total power output than summing up the power outputs of individual seasons. The main advantage of calculating individual seasonal wind-power outputs, however, is that it theoretically permits assessment of interannual variability in power output and capacity factors. Comparison to a known standard may help stakeholders in understanding of uncertainty and interpretation of projected changes. 展开更多
关键词 Sustainability of Wind energy Sensitivity of Wind energy to Decadal Climate variations CESM DOWNSCALING Interannual Variability
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SOME PROBLEMS IN ELECTROSTRICTIVE AND MAGNETOSTRICTIVE MATERIALS 被引量:7
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作者 Kuang Zhen-Bang 《Acta Mechanica Solida Sinica》 SCIE EI 2007年第3期219-227,共9页
Some of the previous theories in the electrostrictive and magnetostrictive materials and their differences are discussed in this paper. A variational principle in the general thermodynamic sense is given and the gover... Some of the previous theories in the electrostrictive and magnetostrictive materials and their differences are discussed in this paper. A variational principle in the general thermodynamic sense is given and the governing equations can be derived from this principle. Illustrational examples are given. 展开更多
关键词 electrostrictive and magnetostrictive materials energy variational principle governing equation electromagnetive ponderomotive force
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Joint Bearing Mechanism of Coal Pillar and Backfilling Body in Roadway Backfilling Mining Technology 被引量:2
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作者 Zhengzheng Cao Ping Xu +3 位作者 Zhenhua Li Minxia Zhang Yu Zhao Wenlong Shen 《Computers, Materials & Continua》 SCIE EI 2018年第2期137-159,共23页
In the traditional mining technology,the coal resources trapped beneath surface buildings,railways,and water bodies cannot be mined massively,thereby causing the lower coal recovery and dynamic disasters.In order to s... In the traditional mining technology,the coal resources trapped beneath surface buildings,railways,and water bodies cannot be mined massively,thereby causing the lower coal recovery and dynamic disasters.In order to solve the aforementioned problems,the roadway backfilling mining technology is developed and the joint bearing mechanism of coal pillar and backfilling body is presented in this paper.The mechanical model of bearing system of coal pillar and backfilling body is established,by analyzing the basic characteristics of overlying strata deformation in roadway backfilling mining technology.According to the Ritz method in energy variation principle,the elastic solution expression of coal pillar deformation is deduced in roadway backfilling mining technology.Based on elastic-viscoelastic correspondence principle,combining with the burgers rheological constitutive model and Laplace transform theory,the viscoelastic solution expression of coal pillar deformation is obtained in roadway backfilling mining technology.By analyzing the compressive mechanical property of backfilling body,the time formula required for coal pillar and backfilling body to play the joint bearing function in roadway backfilling mining technology is obtained.The example analysis indicates that the time is 140 days.The results can be treated as an important basis for theoretical research and process design in roadway backfilling mining technology. 展开更多
关键词 Roadway backfilling mining technology coal pillar backfilling body joint bearing mechanism energy variation principle
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A new interpolating method based on the variation of spectra energy using CMOS array 被引量:1
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作者 汤天瑾 曹向群 +1 位作者 陈洪璆 林斌 《Chinese Optics Letters》 SCIE EI CAS CSCD 2005年第2期80-82,共3页
A new interpolating method to enhance the resolution of gratings using complementary metal-oxide semiconductor (CMOS) according to the variation of soIne specified spectral light intensities during the motion of sca... A new interpolating method to enhance the resolution of gratings using complementary metal-oxide semiconductor (CMOS) according to the variation of soIne specified spectral light intensities during the motion of scale grating in a periodic separation is proposed. CMOS image sensor (pixel array 648 × 488) was also introduced as receiving device and its stability was verified experimentally. Many factors m the experiment were analyzed theoretically and contrasted with experiment. The advantages of this novel method were featured by CMOS and the specified spectral variation of the energy distribution was discussed. 展开更多
关键词 CMOS A new interpolating method based on the variation of spectra energy using CMOS array
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Optimal Operation of Energy Internet Based on User Electricity Anxiety and Chaotic Spatial Variation Particle Swarm Optimization 被引量:1
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作者 Dongsheng Yang Qianqian Chong +1 位作者 Bo Hu Min Ma 《Tsinghua Science and Technology》 SCIE EI CAS CSCD 2018年第3期243-253,共11页
Ignoring load characteristics and not considering user feeling with regard to the optimal operation of Energy Internet(EI) results in a large error in optimization. Thus, results are not consistent with the actual o... Ignoring load characteristics and not considering user feeling with regard to the optimal operation of Energy Internet(EI) results in a large error in optimization. Thus, results are not consistent with the actual operating conditions. To solve these problems, this paper proposes an optimization method based on user Electricity Anxiety(EA) and Chaotic Space Variation Particle Swarm Optimization(CSVPSO). First, the load is divided into critical load, translation load, shiftable load, and temperature load. Then, on the basis of the different load characteristics,the concept of the user EA degree is presented, and the optimization model of the EI is provided. This paper also presents a CSVPSO algorithm to solve the optimization problem because the traditional particle swarm optimization algorithm takes a long time and particles easily fall into the local optimum. In CSVPSO, the particles with lower fitness value are operated by using cross operation, and velocity variation is performed for particles with a speed lower than the setting threshold. The effectiveness of the proposed method is verified by simulation analysis.Simulation results show that the proposed method can be used to optimize the operation of EI on the basis of the full consideration of the load characteristics. Moreover, the optimization algorithm has high accuracy and computational efficiency. 展开更多
关键词 Electricity Anxiety(EA) energy Internet(EI) chaotic spatial variation particle swarm optimization optimal operation
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The Variable-Step L1 Scheme Preserving a Compatible Energy Law for Time-Fractional Allen-Cahn Equation
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作者 Hong-Lin Liao Xiaohan Zhu Jindi Wang 《Numerical Mathematics(Theory,Methods and Applications)》 SCIE CSCD 2022年第4期1128-1146,共19页
In this work,we revisit the adaptive L1 time-stepping scheme for solving the time-fractional Allen-Cahn equation in the Caputo’s form.The L1 implicit scheme is shown to preserve a variational energy dissipation law o... In this work,we revisit the adaptive L1 time-stepping scheme for solving the time-fractional Allen-Cahn equation in the Caputo’s form.The L1 implicit scheme is shown to preserve a variational energy dissipation law on arbitrary nonuniform time meshes by using the recent discrete analysis tools,i.e.,the discrete orthogonal convolution kernels and discrete complementary convolution kernels.Then the discrete embedding techniques and the fractional Gronwall inequality are applied to establish an L^(2)norm error estimate on nonuniform time meshes.An adaptive time-stepping strategy according to the dynamical feature of the system is presented to capture the multi-scale behaviors and to improve the computational performance. 展开更多
关键词 Time-fractional Allen-Cahn equation adaptive L1 scheme variational energy dissipation law orthogonal convolution kernels complementary convolution kernels
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Condition monitoring and fault diagnosis strategy of railway point machines using vibration signals
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作者 Yongkui Sun Yuan Cao +2 位作者 Haitao Liu Weifeng Yang Shuai Su 《Transportation Safety and Environment》 EI 2023年第2期27-37,共11页
Condition monitoring of railway point machines is important for train operation safety and effectiveness.Referring to the fields of mechanical equipment fault detection,this paper proposes a fault detection and identi... Condition monitoring of railway point machines is important for train operation safety and effectiveness.Referring to the fields of mechanical equipment fault detection,this paper proposes a fault detection and identification strategy of railway point machines via vibration signals.A comprehensive feature distilling approach by combining variational mode decomposition(VMD)energy entropy and time-and frequency-domain statistical features is presented,which is more effective than single type of feature.The optimal set of features was selected with ReliefF,which helps improve the diagnosis accuracy.Support vector machine(SVM),which is suitable for a small sample,is adopted to realize diagnosis.The diagnosis accuracy of the proposed method reaches 100%,and its effectiveness is verified by experiment comparisons.In this paper,vibration signals are creatively adopted for fault diagnosis of railway point machines.The presented method can help guide field maintenance staff and also provide reference for fault diagnosis of other equipment. 展开更多
关键词 railway point machines condition monitoring variational mode decomposition(VMD)energy entropy statistical features
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Active spot-scanning test with heavy ions at HIRFL-CSR 被引量:1
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作者 戴中颖 李强 +3 位作者 刘新国 金晓东 黄齐艳 肖国青 《Chinese Physics C》 SCIE CAS CSCD 2012年第8期784-791,共8页
An active spot beam delivery system for heavy ion therapy has been developed based on the Cooling Storage Ring at HIRFL-CSR, where the pencil carbon-ion beams were scanned within a target volume transversely by a pair... An active spot beam delivery system for heavy ion therapy has been developed based on the Cooling Storage Ring at HIRFL-CSR, where the pencil carbon-ion beams were scanned within a target volume transversely by a pair of orthogonal (horizontal and vertical) dipole magnets to paint the slices of the target volume and longitudinally by active energy variation of the synchrotron slice by slice. The unique techniques such as dose shaping via active energy variation and magnetic deflection constitute a promising three-dimensional conformal even intensity-modulated radiotherapy with heavy ions at HIRFL-CSR. In this paper, the verification of active energy variation and the calibration of steerable beam deflection are shown, as the basic functionality components of the active spot-scanning system. Additionally, based on the capability of creating homogeneous irradiation fields with steerable pencil beams, a radiobiological experiment like cell survival measurement has been performed aiming at comparison of the radiobiological effects under active and passive beam deliveries. 展开更多
关键词 spot-scanning heavy ion radiotherapy beam delivery active energy variation
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