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Research on Optimal Configuration of Energy Storage in Wind-Solar Microgrid Considering Real-Time Electricity Price
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作者 Zhenzhen Zhang Qingquan Lv +4 位作者 Long Zhao Qiang Zhou pengfei gao Yanqi Zhang Yimin Li 《Energy Engineering》 EI 2023年第7期1637-1654,共18页
Capacity allocation and energy management strategies for energy storage are critical to the safety and economical operation of microgrids.In this paper,an improved energymanagement strategy based on real-time electric... Capacity allocation and energy management strategies for energy storage are critical to the safety and economical operation of microgrids.In this paper,an improved energymanagement strategy based on real-time electricity price combined with state of charge is proposed to optimize the economic operation of wind and solar microgrids,and the optimal allocation of energy storage capacity is carried out by using this strategy.Firstly,the structure and model of microgrid are analyzed,and the outputmodel of wind power,photovoltaic and energy storage is established.Then,considering the interactive power cost between the microgrid and the main grid and the charge-discharge penalty cost of energy storage,an optimization objective function is established,and an improved energy management strategy is proposed on this basis.Finally,a physicalmodel is built inMATLAB/Simulink for simulation verification,and the energy management strategy is compared and analyzed on sunny and rainy days.The initial configuration cost function of energy storage is added to optimize the allocation of energy storage capacity.The simulation results show that the improved energy management strategy can make the battery charge-discharge response to real-time electricity price and state of charge better than the traditional strategy on sunny or rainy days,reduce the interactive power cost between the microgrid system and the power grid.After analyzing the change of energy storage power with cost,we obtain the best energy storage capacity and energy storage power. 展开更多
关键词 Energy storage optimization real-time electricity price state of charge energy management strategy interactive power
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新形势下电力设计院乡村振兴业务转型思路研究——以中国能建西北院勘测工程公司为例
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作者 高鹏飞 车晓敏 《工程设计与施工》 2023年第12期70-72,共3页
随着电力设计公司转型的不断落实,各电力设计院拓宽国际、发电、电网、新能源、市政、勘测、环保、数字“八大赛道”,新业务的发展转型已经迫在眉睫。论文阐述了电力设计院乡村振兴业务范畴,分析了乡村振兴业务当前发展的外部形势及市... 随着电力设计公司转型的不断落实,各电力设计院拓宽国际、发电、电网、新能源、市政、勘测、环保、数字“八大赛道”,新业务的发展转型已经迫在眉睫。论文阐述了电力设计院乡村振兴业务范畴,分析了乡村振兴业务当前发展的外部形势及市场格局。以中国能建西北院勘测工程公司为例,结合实践探索经验,在新形势下提出了开发乡村振兴业务准入,乡村振兴延伸性课题研究,打造乡村振兴切入点,加大技术研究储备,主动对接市场需求等转型升级的尝试性思路,为同类企业的发展提供可借鉴的经验。 展开更多
关键词 电力设计院 乡村振兴业务 转型升级
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Isolation and Screening of Lactic Acid Bacterial Strains with Antibacterial Properties from the Vaginas of Healthy Cows
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作者 Chao Cheng Qiaozhen Tian +7 位作者 Shaofeng Su Hui Zhang Hongjie Guo pengfei gao Songhe Xu Zhiguo Liu Yanfen Ma Zhenjun Li 《Open Journal of Animal Sciences》 CAS 2022年第3期390-406,共17页
In the present study, eight strains were isolated from 20 cow vagina samples and identified using phenotype, biochemical analysis, sugar fermentation tests, and 16S rRNA sequence analysis. Among eight strains, only SQ... In the present study, eight strains were isolated from 20 cow vagina samples and identified using phenotype, biochemical analysis, sugar fermentation tests, and 16S rRNA sequence analysis. Among eight strains, only SQ0048 was identified as Lactobacillus johnsonii based on a series of biochemical testing (including the adhesion test, catalase test, bacteriocin production test, antibacterial test, and pH value), suggesting that its biological activity was superior to the other seven strains. Furthermore, SQ0048 had the lowest pH value (4.32) and the shortest fermentation time (8 h) compared with the other strains. The adhesion rate of SQ0048 was significantly higher than that of Lactobacillus delbrueckii, with an average adhesion number of 304 ± 2.67. The hydrogen peroxide production testing in SQ0048 was positive;in addition, bacteriocin gene of SQ0048, encoding an approximately 10-kDa product, was successfully cloned, expressed, and detected using the SDS-PAGE method. Meanwhile, SQ0048 had a weak inhibitory effect on Staphylococcus aureus and Escherichia coli. However, the expression products of the bacteriocin gene of SQ0048 had a very strong inhibitory effect on S. aureus and E. coli, with inhibition zone sizes of 18 ± 0.45 mm and 15 ± 0.60 mm, respectively. These data showed that SQ0048 has excellent antibacterial properties compared with other isolated strains and is a potential probiotic candidate to improve the health of the vaginas of cows by inhibiting pathogenic microorganisms. 展开更多
关键词 Antibacterial Properties COW Lactic Acid Bacteria SQ0048 VAGINA
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超高速撞击条件下靶体损伤区的数值模拟分析
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作者 钱秉文 周刚 +7 位作者 陈春林 李名锐 高鹏飞 王可慧 戴湘晖 李明 马坤 吴崇欣 《固体力学学报》 CAS CSCD 北大核心 2024年第1期29-37,共9页
超高速撞击问题中,靶体损伤区研究能够弥补部分实验中难以精确获取成坑形貌的问题,为撞击机理研究和数值模拟的校验提供重要依据.损伤区的数值模拟研究开展较少,主要原因是缺乏经过实验验证的损伤区判据.本文总结了已有的损伤区定量测... 超高速撞击问题中,靶体损伤区研究能够弥补部分实验中难以精确获取成坑形貌的问题,为撞击机理研究和数值模拟的校验提供重要依据.损伤区的数值模拟研究开展较少,主要原因是缺乏经过实验验证的损伤区判据.本文总结了已有的损伤区定量测量实验结果,发现对于同一种靶体,多种切片显微测试方法得到的损伤区深度比较吻合,这给损伤区分析提供了便利.基于iSALE程序模拟分析了累计塑性应变、损伤因子和峰值压力作为损伤区判断参数的适用性,认为TPS=0.1适合作为损伤判据;D=1可以作为损伤判据,但误差较大需谨慎使用;峰值压力不适合作为损伤判据.通过参数化分析发现,随着孔隙率增大和靶体强度增大,损伤区深度逐渐减小. 展开更多
关键词 超高速撞击 损伤区 塑性应变 损伤因子 峰值压力
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Modeling and Simulation Analysis of Solar Thermal Electric Plants Based on Petri Net
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作者 Rong Huang Xiaojuan Lu +2 位作者 Zeping Liang pengfei gao Tian Liang 《Energy Engineering》 EI 2022年第4期1711-1728,共18页
At present,solar thermal power generation is in the demonstration stage,and the large-scale production is affected by many factors.In view of the characteristics of different operating modes of photothermal power gene... At present,solar thermal power generation is in the demonstration stage,and the large-scale production is affected by many factors.In view of the characteristics of different operating modes of photothermal power generation,it is analyzed that the turbine needs to be started and stopped frequently due to different operating modes,which will lead to the instability of the output energy and the reduction of power generation efficiency.In this paper,the dynamic equation of energy conversion process is established by using the law of conservation of energy and conservation of mass.Combined with the logic switching criterion of the system,the system model was established by using the extended differential Petri net,and the validity and accuracy of the model were verified.Through the Petri net model of the system,the system’s working mode switching and power generation situation are analyzed due to the difference of direct normal irradiation intensity(DNI).Finally,the accuracy of the model is proved by comparing it with experimental data of the photovoltaic and thermal demonstration projects that have been connected to the grid. 展开更多
关键词 Solar power hybrid system petri nets direct molten salt mode switch
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The Impact of E-commerce on the Development of Regional Economy and Its Analysis of Security Strategy
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作者 pengfei gao 《International Journal of Technology Management》 2015年第5期59-62,共4页
关键词 区域经济发展 电子商务 安全战略 交易模式
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Al基含能结构材料的Johnson-Cook本构模型及失效参数研究
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作者 陈春林 马坤 +8 位作者 杨锦程 曹进 尹立新 冯娜 高鹏飞 汪存显 李顺 周刚 钱秉文 《固体力学学报》 CAS CSCD 北大核心 2023年第6期782-794,共13页
利用万能实验机和Hopkinson杆装置测试了Al基含能结构材料在不同温度下的静动态力学性能,分析实验结果得到了温度效应和应变率效应对材料力学性能的影响及该合金的Johnson-Cook本构模型参数.结合二维数字图像相关(DIC)方法,研究了Al基... 利用万能实验机和Hopkinson杆装置测试了Al基含能结构材料在不同温度下的静动态力学性能,分析实验结果得到了温度效应和应变率效应对材料力学性能的影响及该合金的Johnson-Cook本构模型参数.结合二维数字图像相关(DIC)方法,研究了Al基含能结构材料的失效应变与应力三轴度及温度之间的关系,得到了该合金的Johnson-Cook失效模型参数.通过平面撞击实验获得了Al基含能结构材料粒子速度和应力波波速之间的经验线性关系和该合金的Grüneisen系数.基于实验获得的材料本构关系和状态方程参数,完成了Al基含能结构材料超高速撞击多层间隔薄钢板的数值模拟,结果表明,数值模拟中靶板的毁伤模式、破孔直径及弹坑主要散布区和实验结果吻合. 展开更多
关键词 力学性能 HOPKINSON杆 DIC方法 Al基含能结构材料 Johnson-Cook本构模型 Johnson-Cook失效模型 状态方程
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Total conversion of centimeter-scale nickel foam into single atom electrocatalysts with highly selective CO_(2)electrocatalytic reduction in neutral electrolyte 被引量:3
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作者 Qikui Fan pengfei gao +4 位作者 Shan Ren Yunteng Qu Chuncai Kong Jian Yang Yuen Wu 《Nano Research》 SCIE EI CSCD 2023年第2期2003-2010,共8页
To improve the atomic utilization of metals and reduce the cost of industrialization,the one-step total monoatomization of macroscopic bulk metals,as opposed to nanoscale metals,is effective.In this study,we used a th... To improve the atomic utilization of metals and reduce the cost of industrialization,the one-step total monoatomization of macroscopic bulk metals,as opposed to nanoscale metals,is effective.In this study,we used a thermal diffusion method to directly convert commercial centimeter-scale Ni foam to porous Ni single-atom-loaded carbon nanotubes(CNTs).As expected,owing to the coating of single-atom on porous,highly conductive CNT carriers,Ni single-atom electrocatalysts(Ni-SACs)exhibit extremely high activity and selectivity in CO_(2)electroreduction(CO_(2)RR),yielding a current density of>350 mA/cm^(2),a selectivity for CO of>91%under a flow cell configuration using a 1 M potassium chloride(KCl)electrolyte.Based on the superior activity of the Ni-SACs electrocatalyst,an integrated gas-phase electrochemical zero-gap reactor was introduced to generate a significant amount of CO current for potential practical applications.The overall current can be increased to 800 mA,while maintaining CO Faradaic efficiencies(FEs)at above 90%per unit cell.Our findings and insights on the active site transformation mechanism for macroscopic bulk Ni foam conversion into single atoms can inform the design of highly active single-atom catalysts used in industrial CO_(2)RR systems. 展开更多
关键词 Ni single atom electrocatalyst CO_(2)electroreduction to CO neutral electrolyte thermal diffusion
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Design of manganese ion coated Prussian blue nanocarrier for the therapy of refractory diffuse large B-cell lymphoma based on a comprehensive analysis of ferroptosis regulators from clinical cases
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作者 Yulu Yang Rui Chen +4 位作者 Ke Li pengfei gao Yi Gong Weihu Yang Kaiyong Cai 《Nano Research》 SCIE EI CSCD 2023年第4期5265-5278,共14页
Diffuse large B-cell lymphoma(DLBCL)is a prevalent human malignancy,and understanding its biology will help identify problems in refractory patients and customize alternative therapies for them.We found that DLBCL can... Diffuse large B-cell lymphoma(DLBCL)is a prevalent human malignancy,and understanding its biology will help identify problems in refractory patients and customize alternative therapies for them.We found that DLBCL can be stratified into two independent subtypes with different clinical characteristics and outcomes by consensus clustering of expression of ferroptosis regulatory genes,which proves that ferroptosis is effective in treating refractory cases.In this work,we constructed a novel ferroptosis nanocarrier(PBPMn@PEG)by coating Prussian blue nanoparticles with manganese ions and encapsulating them with poly(ethyleneglycol).The low efficiency of the Fenton reaction of Prussian blue nanoparticles can be improved greatly by manganese coating,and can effectively generate hydroxyl radicals,and induce ferroptosis of lymphoma cells(SU-DHL-10 cells)by down-regulating ferroptosis suppressor genes and up-regulating ferroptosis driver genes.It also induces effective cell apoptosis,which is synergistic with ferroptosis for DLBCL therapy.In vivo experiments also prove that PBPMn@PEG achieved a better anti-tumor effect by up-regulating COX2,HO-1/hemeoxygenase-1(HMOX1),and NADPH oxidase-4(NOX4),and downregulating FSP1 and GPX4,with lower biotoxicity.As a novel and potential DLBCL drug carrier,our discovery served as a foundation for the treatment of the refractory DLBCL by inducing ferroptosis for DLBCL treatment in addition to the therapeutic effect of drugs. 展开更多
关键词 diffuse large B-cell lymphoma(DLBCL) ferroptosis Prussian blue nanoparticles manganese ion tumor therapy
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VenomAttack: automated and adaptive activity hijacking in Android
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作者 Pu SUN Sen CHEN +3 位作者 Lingling FAN pengfei gao Fu SONG Min YANG 《Frontiers of Computer Science》 SCIE EI CSCD 2023年第1期187-204,共18页
Activity hijacking is one of the most powerful attacks in Android. Though promising, all the prior activity hijacking attacks suffer from some limitations and have limited attack capabilities. They no longer pose secu... Activity hijacking is one of the most powerful attacks in Android. Though promising, all the prior activity hijacking attacks suffer from some limitations and have limited attack capabilities. They no longer pose security threats in recent Android due to the presence of effective defense mechanisms. In this work, we propose the first automated and adaptive activity hijacking attack, named VenomAttack, enabling a spectrum of customized attacks (e.g., phishing, spoofing, and DoS) on a large scale in recent Android, even the state-of-the-art defense mechanisms are deployed. Specifically, we propose to use hotpatch techniques to identify vulnerable devices and update attack payload without re-installation and re-distribution, hence bypassing offline detection. We present a newly-discovered flaw in Android and a bug in derivatives of Android, each of which allows us to check if a target app is running in the background or not, by which we can determine the right attack timing via a designed transparent activity. We also propose an automated fake activity generation approach, allowing large-scale attacks. Requiring only the common permission INTERNET, we can hijack activities at the right timing without destroying the GUI integrity of the foreground app. We conduct proof-of-concept attacks, showing that VenomAttack poses severe security risks on recent Android versions. The user study demonstrates the effectiveness of VenomAttack in real-world scenarios, achieving a high success rate (95%) without users’ awareness. That would call more attention to the stakeholders like Google. 展开更多
关键词 ANDROID activity hijacking Android security mobile security
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Luteolin suppresses oral carcinoma 3(OC3) cell growth and migration via modulating polo-like kinase 1(PLK1) expression and cellular energy metabolism
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作者 pengfei gao Wentao ZHANG +5 位作者 Yujie LIN Ruijie LU Zijian LOU Gang LU Ruolang PAN Yunfang CHEN 《Journal of Zhejiang University-Science B(Biomedicine & Biotechnology)》 SCIE CAS CSCD 2023年第12期1151-1158,共8页
Oral squamous cell carcinoma(OSCC)is a prevalent malignant tumor affecting the head and neck region(Leemans et al.,2018).It is often diagnosed at a later stage,leading to a poor prognosis(Muzaffar et al.,2021;Li et al... Oral squamous cell carcinoma(OSCC)is a prevalent malignant tumor affecting the head and neck region(Leemans et al.,2018).It is often diagnosed at a later stage,leading to a poor prognosis(Muzaffar et al.,2021;Li et al.,2023).Despite advances in OSCC treatment,the overall 5-year survival rate of OSCC patients remains alarmingly low,falling below 50%(Jehn et al.,2019;Johnson et al.,2020).According to statistics,only 50%of patients with oral cancer can be treated with surgery.Once discovered,it is more frequently at an advanced stage.In addition,owing to the aggressively invasive and metastatic characteristics of OSCC,most patients die within one year of diagnosis.Hence,the pursuit of novel therapeutic drugs and treatments to improve the response of oral cancer to medication,along with a deeper understanding of their effects. 展开更多
关键词 PLK1 METABOLISM DRUGS
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NEHASH:high-concurrency extendible hashing for non-volatile memory
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作者 Tao CAI pengfei gao +3 位作者 Dejiao NIU Yueming MA Tianle LEI Jianfei DAI 《Frontiers of Information Technology & Electronic Engineering》 SCIE EI CSCD 2023年第5期703-715,共13页
Extendible hashing is an effective way to manage increasingly large file system metadata,but it suffers from low concurrency and lack of optimization for non-volatile memory(NVM).In this paper,a multilevel hash direct... Extendible hashing is an effective way to manage increasingly large file system metadata,but it suffers from low concurrency and lack of optimization for non-volatile memory(NVM).In this paper,a multilevel hash directory based on lazy expansion is designed to improve the concurrency and efficiency of extendible hashing,and a hash bucket management algorithm based on groups is presented to improve the efficiency of hash key management by reducing the size of the hash bucket,thereby improving the performance of extendible hashing.Meanwhile,a hierarchical storage strategy of extendible hashing for NVM is given to take advantage of dynamic random access memory(DRAM)and NVM.Furthermore,on the basis of the device driver for Intel Optane DC Persistent Memory,the prototype of high-concurrency extendible hashing named NEHASH is implemented.Yahoo cloud serving benchmark(YCSB)is used to test and compare with CCEH,level hashing,and cuckoo hashing.The results show that NEHASH can improve read throughput by up to 16.5%and write throughput by 19.3%. 展开更多
关键词 Extendible hashing Non-volatile memory(NVM) High concurrency
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Deformation behavior and microstructure evolution of titanium alloys with lamellar microstructure in hot working process: A review 被引量:22
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作者 pengfei gao Mingwang Fu +2 位作者 Mei Zhan Zhenni Lei Yanxi Li 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2020年第4期56-73,共18页
Titanium alloys have been widely used in many industrial clusters such as automotive, aerospace and biomedical industries due to their excellent comprehensive properties. In order to obtain fine microstructures and fa... Titanium alloys have been widely used in many industrial clusters such as automotive, aerospace and biomedical industries due to their excellent comprehensive properties. In order to obtain fine microstructures and favorable properties, a well-designed multi-step thermomechanical processing(TMP) is critically needed in manufacturing of titanium components. In making of titanium components,subtransus processing is a critical step to breakdown lamellar microstructure to fine-structure in hot working process and thus plays a key role in tailoring the final microstructure and properties. To realize this goal, huge efforts have been made to investigate the mechanisms of microstructure evolution and flow behavior during the subtransus processing. This paper reviews the recent experimental and modelling progresses, which aim to provide some guidelines for the process design and microstructure tailoring for titanium alloy research community. The characteristics of the initial lamellar microstructure are presented, followed by the discussion on microstructure evolution during subtransus processing. The globularization of lamellar α is analyzed in detail from three aspects, i.e., globularization mechanism, heterogeneity and kinetics. The typical features of flow behaviors and the explanations of significant flow softening are then summarized. The recent advances in modelling of microstructure evolution and flow behaviors in the subtransus processing are also articulated. The current tantalized issues and challenges in understanding of the microstructure evolution and flow behaviors of the titanium alloys with lamellar microstructure are presented and specified in future exploration of them. 展开更多
关键词 TITANIUM alloys LAMELLAR MICROSTRUCTURE Deformation behavior MICROSTRUCTURE evolution
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Unequal-thickness billet optimization in transitional region during isothermal local loading forming of Ti-alloy rib-web component using response surface method 被引量:13
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作者 Ke WEI Mei ZHAN +3 位作者 Xiaoguang FAN He YANG pengfei gao Miao MENG 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2018年第4期845-859,共15页
Avoiding the folding defect and improving the die filling capability in the transitional region are desired in isothermal local loading forming of a large-scale Ti-alloy rib-web component(LTRC). To achieve a high-pr... Avoiding the folding defect and improving the die filling capability in the transitional region are desired in isothermal local loading forming of a large-scale Ti-alloy rib-web component(LTRC). To achieve a high-precision LTRC, the folding evolution and die filling process in the transitional region were investigated by 3 D finite element simulation and experiment using an equal-thickness billet(ETB). It is found that the initial volume distribution in the second-loading region can greatly affect the amount of material transferred into the first-loading region during the second-loading step, and thus lead to the folding defect. Besides, an improper initial volume distribution results in non-concurrent die filling in the cavities of ribs after the second-loading step, and then causes die underfilling. To this end, an unequal-thickness billet(UTB) was employed with the initial volume distribution optimized by the response surface method(RSM). For a certain eigenstructure, the critical value of the percentage of transferred material determined by the ETB was taken as a constraint condition for avoiding the folding defect in the UTB optimization process,and the die underfilling rate was considered as the optimization objective. Then, based on the RSM models of the percentage of transferred material and the die underfilling rate, non-folding parameter combinations and optimum die filling were achieved. Lastly, an optimized UTB was obtained and verified by the simulation and experiment. 展开更多
关键词 Die filling Folding defect Isothermal local loading forming Transitional region Unequal-thickness billet optimization
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Effect of feeding Lactobacillus plantarum P-8 on the faecal microbiota of broiler chickens exposed to lincomycin 被引量:7
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作者 pengfei gao Qiangchuan Hou +3 位作者 Lai-Yu Kwok Dongxue Huo Shuzhen Feng Heping Zhang 《Science Bulletin》 SCIE EI CAS CSCD 2017年第2期105-113,共9页
Poultry and eggs are nutritious and healthy foods that contain high-quality proteins and low levels of fat compared with other meats. Recent studies have shown that poultry performance is closely associated with colon... Poultry and eggs are nutritious and healthy foods that contain high-quality proteins and low levels of fat compared with other meats. Recent studies have shown that poultry performance is closely associated with colonic health. Antibiotics are commonly used in the poultry industry to control diseases and enhance survival rates. However, antibiotic use can also result in host gut dysbiosis and immune dysregulation. Such imbalances compromise poultry health and growth performance. Thus, our study investigated the effect of Lactobacillus(L.) plantarum P-8 on the gut microbiome of chickens co-inoculated with the antibiotic lincomycin. Principal coordinate analysis showed that L. plantarum P-8 treatment shifted the faecal bacterial population structure. At the metagenomic level, the Clusters of Orthologous Groups(COGs) functional categories of P, C, N and A were overrepresented in the probiotic group. Additionally, the relative gene abundances of metabolic pathways involved in flagellar assembly,bacterial chemotaxis, nitrogen metabolism, sulfur metabolism, cofactor and vitamin biosynthesis were also higher in the probiotic group than the control; in contrast genes related to galactose degradation,carbon fixation, multiple sugar transport systems and ribosomes were underrepresented in the probiotic group. Our data suggest that feeding L. plantarum P-8 has the potential to improve metabolic activity and nutrient utilization of poultry. Furthermore, the faecal antibiotic resistomes of the two groups could be separated using principal components analysis, indicating that the probiotic treatment may modulate the intestinal antibiotic resistance gene pool by changing the population structure of the gut microbiota.This study has provided interesting insights into the application of probiotics in the poultry industry. 展开更多
关键词 植物乳杆菌 粪便菌群 林可霉素 肠道微生态 家禽健康 肉鸡 饲喂 主成分分析法
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Mesoscale deformation mechanisms in relation with slip and grain boundary sliding in TA15 titanium alloy during tensile deformation 被引量:6
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作者 Yanxi Li pengfei gao +3 位作者 Jingyue Yu Shuo Jin Shuqun Chen Mei Zhan 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2022年第3期72-86,共15页
Revealing the mesoscale deformation mechanisms of titanium alloy with tri-modal microstructure is of great significance to improve its mechanical properties. In this work, the collective behavior and mechanisms of sli... Revealing the mesoscale deformation mechanisms of titanium alloy with tri-modal microstructure is of great significance to improve its mechanical properties. In this work, the collective behavior and mechanisms of slip activities, slip transfer, and grain boundary sliding of tri-modal microstructure were investigated by the combination of quasi-in-situ tensile test, SEM, EBSD and quantitative slip trace analyses. It is found that the slip behavior presents different characteristics in the equiaxed α(α_(p)) and lamellar α(α_(l))grains. Under a low level of deformation, almost all the slip deformation is governed by single basal and prismatic slips for both of α_(p)and α_(l),despite small amount of < a >-pyramidal slip exists in α_(l)grains. As deformation proceeds, < a >-pyramidal and < c + a >-pyramidal slip systems with high Schmid factors were activated in quantities. Specially, certain coarse prismatic slip bands were produced across both of single and colony α_(l)grains whose major axes tilting about 40 °–70 ° from the tensile axis. Slip transfer occurs at the boundaries of α_(p)/α_(p)and α_(l)/β under the condition that there exists perfect alignment between two slip systems and high Schmid factors of outgoing slip system. The slip transfer across α_(l)/β boundary can be divided into two types: straight slip transfer and deflect slip transfer with a deviation angle of 5 °–12 °, depending on the alignment of slip planes of two slip systems. The grain boundary sliding along boundaries of α_(l)/β and α_(p)/β was captured by covering micro-grid on tensile sample. It is found that the crystallographic orientation and the geometrical orientation related to loading axis play great roles in the occurrence of grain boundary sliding. 展开更多
关键词 Titanium alloy Tri-modal microstructure Slip modes Slip transfer Grain boundary sliding
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Effects of a two-meal daily feeding pattern with varied crude protein levels on growth performance and antioxidant indexes in pigs 被引量:7
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作者 Xin Wu Xiaoyun Guo +4 位作者 Chunyan Xie Tianyong Zhang pengfei gao Tianzeng gao Yulong Yin 《Animal Nutrition》 SCIE 2016年第4期267-270,共4页
The present study aimed to evaluate the effects of daily feeding pattern on growth performance, blood biochemistry, and antioxidant indexes in pigs. One hundred and eighty female Duroc x Landrace x Yorkshire(DLY) pigs... The present study aimed to evaluate the effects of daily feeding pattern on growth performance, blood biochemistry, and antioxidant indexes in pigs. One hundred and eighty female Duroc x Landrace x Yorkshire(DLY) pigs with similar body weight(11.00 ± 0.12 kg) were randomly assigned to 3 groups: the control group(fed 17.01% CP diet, twice daily); high-low group(H-L group, fed18.33% CP diet in the morning, followed by 15.70% CP diet in the afternoon); and low-high group(L-H group, fed 15.70% CP diet in the morning, followed by 18.33% CP diet in the afternoon)(n = 6). Comparable amounts of their respective diets were given at 05:30 and 15:00 throughout the experimental periods to make all the treatments consumed the same type of food and the same amount of calories on a daily basis. On day 30, one pig was randomly selected per litter for blood samples. Compared with the control group, ADG in the H-L and L-H groups increased by 8.11% and 16.23%, but not significant(P > 0.05); and blood urea nitrogen(BUN) in the H-L and L-H groups decreased by 26.76% and 41.04%(P < 0.05), respectively. The H-L group feeding pattern could significantly improve levels of serum superoxide dismutase(SOD), when compared with the control group. These findings suggest that the twomeal daily feeding pattern with varied levels of CP affects serum levels of BUN and SOD. These changes could effectively silightly improve growth performance and antioxidant capacity in pigs without incurring increased feeding costs. 展开更多
关键词 Two-meal daily feeding pattern Crude protein Growth performance Antioxidant index PIGS
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The mechanism of flow softening in subtransus hot working of two-phase titanium alloy with equiaxed structure 被引量:3
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作者 Xiaoguang Fan He Yang pengfei gao 《Chinese Science Bulletin》 SCIE EI CAS 2014年第23期2859-2867,共9页
Understanding the mechanism of high temperature deformation is important for controlling the forming quality of the titanium alloy forgings.In the present work,the flow softening mechanism in subtransus deformation of... Understanding the mechanism of high temperature deformation is important for controlling the forming quality of the titanium alloy forgings.In the present work,the flow softening mechanism in subtransus deformation of titanium alloys with equiaxed structure was investigated by interrupted isothermal compression tests.The results show that limited strain hardening followed by continuous flow softening occurs in high temperature deformation of a twophase TA15 titanium alloy.The flow softening can not be rationalized by dynamic recrystallization.Instead,the increase of mobile dislocations during deformation is an important reason for flow softening.The grain boundaries(including the a-b interfaces)act as an important source for the generation of mobile dislocations.The continuous flow softening results from the significant deformation heterogeneity in subtransus working. 展开更多
关键词 连续流动 两相钛合金 软化 机制 结构 热加工 TA15钛合金 高温变形
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Shape- and size-dependent catalysis activities of iron-terephthalic acid metal-organic frameworks 被引量:3
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作者 Yali Liu pengfei gao +1 位作者 Chengzhi Huang Yuanfang Li 《Science China Chemistry》 SCIE EI CAS CSCD 2015年第10期1553-1560,共8页
Precise control of the size and morphology of metal-organic frameworks(MOFs) presents an important direction for extending these inorganic-organic materials to many more advanced applications. However, because of the ... Precise control of the size and morphology of metal-organic frameworks(MOFs) presents an important direction for extending these inorganic-organic materials to many more advanced applications. However, because of the limit of the crystal-growth rule and mechanism, good-control of the size and morphology of MOFs remains challenging. In this contribution, an iron-terephthalic acid metal-organic framework with different shapes(octahedron, spindle and bipyramidal hexagonal) was easily and reproducibly synthesized via a solvothermal method. Sodium acetate and glycerol were used as modulators. Mechanism studies showed that the crystal nucleation rate and orientational growth both play important roles in determining the final shape of the MOFs. Further investigations showed that the as prepared MOFs exhibit shape-dependent catalytic activities, which means that MOFs can be designed to perform different catalytic functions. This investigation not only provides an effective guideline for the precise control of the size and morphology of metal-organic frameworks, but also extends MOFs to much more advanced applications in terms of catalyst chemistry. 展开更多
关键词 金属有机骨架 对苯二甲酸 催化活性 形状 尺寸 框架 有机材料 精确控制
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Analysis of anisotropy mechanism in the mechanical property of titanium alloy tube formed through hot flow forming 被引量:3
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作者 Zhenni Lei pengfei gao +2 位作者 Xianxian Wang Mei Zhan Hongwei Li 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2021年第27期77-90,共14页
Anisotropy of mechanical property is an important feature influencing the service performance of titanium(Ti)alloy tube component.In this work,it is found that the hot flow formed Ti alloy tube exhibits higher yield s... Anisotropy of mechanical property is an important feature influencing the service performance of titanium(Ti)alloy tube component.In this work,it is found that the hot flow formed Ti alloy tube exhibits higher yield strength along circumferential direction(CD),and larger elongation along rolling direction(RD),presenting significant anisotropy.Subsequently,the quantitative characteristics and underlying mechanism of the property anisotropy were revealed by analyzing the slip,damage and fracture behavior under the combined effects of the spun{0002}basal texture and fibrous microstructure for different loading directions.The results showed that the prismatic slip in primaryαgrain is the dominant deformation mechanism for both loading directions at the yielding stage.The prismatic slip is harder under CD loading,which makes CD loading present higher yield strength than RD loading.Additionally,the yield anisotropy can be quantified through the inverse ratio of the averaged Schmid Factor of the activated prismatic slip under different loading directions.As for the plasticity anisotropy,the harder and slower slip development under CD loading causes that the CD loading presents larger external force and normal stress on slip plane,thus leading to more significant cleavage fracture than RD loading.Moreover,the micro-crack path under RD loading is more tortuous than CD loading because the fibrous microstructure is elongated along RD,which may suppress the macro fracture under RD loading.These results suggest that weakening the texture and fibrous morphology of microstructure is critical to reduce the differences in slip,damage and fracture behavior along different directions,alleviate the property anisotropy and optimize the service performance of Ti alloy tube formed by hot flow forming. 展开更多
关键词 Titanium alloy tube Hot flow forming Mechanical property anisotropy Slip behavior Damage evolution
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