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Natural Solar Drying and Charcoal Production by Pyrolysis of Empty Shells of Cocoa Pods Using a Carbonisation Stove Fitted with a Chimney
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作者 Siaka Touré Adjo Christelle Ogo Modibo Sidibé 《Journal of Energy and Power Engineering》 CAS 2023年第4期109-120,共12页
The world’s production of cocoa highly has grown since 1960.In West Africa,the production reached about 3,000,000 tons in 2012.More than 50%of the world’s production of cocoa comes nowadays from Côte d’Ivoire ... The world’s production of cocoa highly has grown since 1960.In West Africa,the production reached about 3,000,000 tons in 2012.More than 50%of the world’s production of cocoa comes nowadays from Côte d’Ivoire and Ghana and Côte d’Ivoire is the biggest producer.After harvesting,the empty shells,considered as non-useful wastes,are abandoned in the fields where they become a source of pollution.That yields millions of tons of biomass that can be converted into charcoal,instead of being sources of pollution.In the present work,the drying kinetics of the empty wet shells were studied.Then,charcoal production by pyrolysis of those empty shells of cocoa pods was performed,using a carbonisation stove fitted with a chimney.The study showed that the empty shells have a high moisture content.The different phases of the drying were observed.The study compared the drying rates and the diffusion coefficients of a small sample and a big sample.Two experiences of carbonisation of the empty shells were successfully carried out.For the first experiment,the pyrolysis temperatures were recorded and the charcoal mass efficiency calculated.For the second experiment,the temperatures were higher and the result was colored charcoals.The colorations disappeared after some hours. 展开更多
关键词 Shells of cocoa pods solar drying diffusion coefficient charcoal production carbonisation stove.
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基于CocoaPods的iOS开发私有公共基础代码库建设 被引量:1
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作者 陈剑峰 《电子质量》 2022年第9期74-77,共4页
私有公共基础代码库建设一般在大厂等大型团队中都会部署到战略规划列表中,在涉及到机密而又需要复用的代码模块等场景中就需要私有库派上用场了;在建设私有库之前,需要先搭建好内部Git服务器或使用第三方平台私有Git仓库,然后将私有库... 私有公共基础代码库建设一般在大厂等大型团队中都会部署到战略规划列表中,在涉及到机密而又需要复用的代码模块等场景中就需要私有库派上用场了;在建设私有库之前,需要先搭建好内部Git服务器或使用第三方平台私有Git仓库,然后将私有库部署进去;创建索引库用于对所有私有库的索引;创建Cocoa Pods项目并对项目进行配置,将私有库代码模块等相关内容放置Cocoa Pods项目内,将Cocoa Pods项目提交到Git仓库并提交版本信息到索引库内;在项目中通过Cocoa Pods引用私有库进行验证。 展开更多
关键词 私有公共基础代码库建设 Cocoa pods 索引库 Cocoa pods项目 私有库部署
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Effects of ABA on Photosynthetic Characteristics of Pods and Yield of Brassica napus 被引量:4
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作者 李俊 张春雷 +3 位作者 马霓 余利平 晁赢 李玲 《Agricultural Science & Technology》 CAS 2012年第4期760-762,903,共4页
[Objective] The aim was to evaluate the effects of different concentrations of ABA on photosynthetic characteristics of pods and yield of Brassica napus and analyze the relationships between ABA concentration and yiel... [Objective] The aim was to evaluate the effects of different concentrations of ABA on photosynthetic characteristics of pods and yield of Brassica napus and analyze the relationships between ABA concentration and yield components, to provide theoretical basis for cultivation of high-yield rapeseed. [Method] At the end of flowering stage, the rape plants were separately sprayed with 1, 2, 100 and 200μmol/L of ABA; photosynthetic parameters, water use efficiency (WUE), yield and yield components of the rape plants were investigated 0, 5, 10 and 15 d later, respectively. [Result] ABA treatment with different concentrations significantly changed pod photosynthetic parameters and yield components of rapeseed. Low concentra- tions of ABA could improve pod's net photosynthetic rate and yield components while high concentrations had the contrary effect. [Conclusion] Whether ABA func- tioned in inhibiting or promoting role might depend on the interaction between endogenous hormone levels and exogenous ABA concentration. Improvement of WUE would be the main reason for yield increasing. 展开更多
关键词 Brassica napus L POD Abscisic acid (ABA) Photosynthetic characteristics YIELD
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Role of phenolics as antioxidants,biomolecule protectors and as anti-diabetic factors-Evaluation on bark and empty pods of Acacia auriculiformis 被引量:1
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作者 Arumugam Sathya Perumal Siddhuraju 《Asian Pacific Journal of Tropical Medicine》 SCIE CAS 2012年第10期757-765,共9页
Objective:To search for an efficient and inexpensive source of phytoconstituents with antioxidant potential and health promoting traits from bark and empty pods of Acacia auriculiformis (A.auriculiformis).Methods:Sa... Objective:To search for an efficient and inexpensive source of phytoconstituents with antioxidant potential and health promoting traits from bark and empty pods of Acacia auriculiformis (A.auriculiformis).Methods:Samples of bark and empty pod extracts were analyzed for bioactives(phenolics,flavonoids and proanthocyanidins) and subjected to free radical scavenging activity on DPPH<sup>*</sup>,ABTS<sup>?</sup>,OH<sup>?</sup>,O<sub>2</sub><sup>*</sup>,and NO along with the determination of reducing power, iron chelating activity and peroxidation inhibition.Defensive action of extracts on biomolecules and cell membranes were evaluated by DNA nicking assay and haemolysis inhibition assay respectively,α-amylase andα-glucosidase inhibitory potentials were also determined. Results:All the bioactives analyzed were higher in bark(B) than empty pods(EP)[TPC:B (574.51±16.11);EP(96.80±3.45) mg GAE/g.TFC:B(94.71±7.65);EP(24(?)87±20.45) mg RE/g. Proanthocyanidins:B(2.81±0.31);EP(1.25±0.01) mg LE/100 g DM]except flavonoids.Both the extracts showed higher quenching capacity on DPPH and ABTS(DPPH:B(0.21±0.01);EP(1.51±0.17) g extract/g DPPH.ABTS:B(111 519.14±79 340.91);EP(80 232.55±32 894.12) mmol TE/g) with the FRAP of B(84 515.63±3 350.69) and EP(47 940.79±1 257.60) mmol Fe((?))/g.Iron chelation was not observed.In addition,they showed lower quenching activity on OH<sup>?</sup>(B(48.95±1.72);EP(34.94±1.62)%) and equivalent quenching on O<sub>2</sub><sup>?</sup>(B(53.47±3.92);EP(24.41±2.61)%),NO(B(49.04±5.04); EP(51.00±5.13)%),peroxidation inhibition(B(67.50±5.50);EP(55.l±2.3)%) and antihaemolytic potential(B(87.60±6.84)%) towards authentic antioxidant standards.Interestingly,Empty pod extracts are devoid of antihaemolytic activity.Both the extracts showed dose dependent DNA protection.Besides this,bark and empty pod extracts exhibited dual inhibiting potential againstα-amylase andα-glucosidase enzymes.Conclusions:On summarization,it insinuated that both bark and empty pods can be used for the preparation of antioxidant/nutraceutical supplements and in anti-diabetic formulations. 展开更多
关键词 Phenolics BARK EMPTY pods ACACIA auriculiformis Antioxidant activity TypeⅡdiabetes
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PODS管道数据模型及其应用 被引量:6
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作者 陈辉 张文广 +3 位作者 张学峰 李建辉 王传宝 文斌 《天然气与石油》 2008年第6期23-26,共4页
PODS(Pipeline open Database Standard)是长输管道数据模型的国际标准,介绍了PODS发展历史和现状、主要结构和内容,及其在广东大鹏液化天然气有限公司的管道地理信息系统中的应用,可供有关数字管道的研究和建设单位参考。
关键词 数字管道 数据模型 pods GIS
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Morpho-structural Features and Structural Classification of Chromite Pods in the Tropoje-Has Ophiolite Massif, Albania
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作者 Ibrahim MILUSHI Nezir MEKSHIQI 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2016年第S1期234-,共1页
Tropoje-Has ophiolitic massif of eastern Mirdita(Albania)ophiolitic belt,is a major source for metallurgical chromite ore in Albania.Massif consists of a thick mantle section of SSZ type,8-10 km thick and
关键词 Morpho-structural Features and Structural Classification of Chromite pods in the Tropoje-Has Ophiolite Massif Albania
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Mapping QTL affecting the vertical distribution and seed set of soybean [Glycine max(L.) Merr.] pods
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作者 Shiping Liu Hong Xue +16 位作者 Kaixin Zhang Ping Wang Daiqun Su Wenbin Li Shichao Xu Jianan Zhang Zhongying Qi Yanlong Fang Xiyu Li Yue Wang Xiaocui Tian Jie Song Jiajing Wang Chang Yang Sitong Jiang Wen-Xia Li Hailong Ning 《The Crop Journal》 SCIE CAS CSCD 2019年第5期694-706,共13页
Number of pods per plant and number of seeds per pod are quantitative,multigenic traits and important components of yield in soybean[Glycine max(L.)Merr.].Pods are distributed unevenly in the upper,middle,and lower se... Number of pods per plant and number of seeds per pod are quantitative,multigenic traits and important components of yield in soybean[Glycine max(L.)Merr.].Pods are distributed unevenly in the upper,middle,and lower segments of the plant and this distribution is affected by sowing date(SD).A population of four-way recombinant inbred lines(FW-RIL),containing 160 F2:8 individuals,was generated from the cross(Kenfeng 14×Kenfeng 15)×(Heinong 48×Kenfeng 19).A linkage map consisting of 275 simple sequence repeat(SSR)markers was used to map quantitative trait loci(QTL)associated with the production of one,two,three,and four seeds per pod in the upper,middle,and lower segments of plants at two SDs,totaling 12 measurements per SD.A wide range of variation in the twelve characteristics was observed among the four parental lines and the FW-RIL population at the two SDs.The effect of SD2(May 17,2016)on pod number was stronger than that of SD1(May 7,2016)because the heritability of each trait in the SD1 experiment was generally greater than that of SD2.The study identified 76 QTL controlling pod number,with the phenotypic variation explained by each QTL ranging from 1.86%to 13.71%.The numbers of QTL controlling one,two,three,and four seeds per pod were 28,23,23,and 23,respectively.There were 30,28,and 28 QTL controlling the pod number in the upper,middle,and lower segments of the plant,respectively.Forty-five QTL were identified at SD1 and 38 QTL were identified at SD2.Seventeen QTL were associated with pod-number traits.The QTL qPNA1–3 was associated with the number of pods containing one seed in the middle segment of the plant at both SDs.Sixty-three QTL were published QTL(common areas existed when integrating on a map GmComposite2003 of Wm82 based on left and right markers).and 13 QTL related to pod number were newly discovered.These results provide a reference for breeders to improve soybean yield by combining advantageous alleles for these QTL.Future studies may reveal candidate genes for these QTL and identify causal alleles for markerassisted selection. 展开更多
关键词 SOYBEAN Pod number QTL SOWING date Vertical distribution
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HOI延迟对LEO卫星简化动力学POD的影响 被引量:2
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作者 张兵良 方卓 +1 位作者 李珊珊 曾彬 《导航定位与授时》 CSCD 2024年第1期79-86,共8页
通常使用无电离层(IF)线性组合(LC)消除低地球轨道(LEO)卫星简化动力学精密定轨(POD)一阶电离层延迟误差,忽略了高阶电离层(HOI)延迟误差。随着LEO卫星POD技术的发展,计算不同轨道高度的HOI延迟并探索其变化已成为进一步提高POD精度的... 通常使用无电离层(IF)线性组合(LC)消除低地球轨道(LEO)卫星简化动力学精密定轨(POD)一阶电离层延迟误差,忽略了高阶电离层(HOI)延迟误差。随着LEO卫星POD技术的发展,计算不同轨道高度的HOI延迟并探索其变化已成为进一步提高POD精度的重要手段。首先,使用国际参考电离层-2016(IRI-2016)和国际地磁参考场第13代(IGRF-13)模型,计算电离层穿刺点(IPP)位置和地磁场强度。其次,使用平滑星载GNSS数据计算电离层斜路径总电子含量(STEC)。然后,分别计算GOCE、GRACE-A和SWARM-A/B卫星的二阶和三阶电离层延迟。最后,评估了HOI延迟对LEO卫星重叠轨道分析、卫星激光测距(SLR)检核和精密科学轨道(PSO)比较结果的影响。实验结果表明:HOI延迟对LEO卫星简化动力学POD的影响大约在毫米至厘米的数量级上;HOI延迟对LEO卫星简化动力学POD外符合精度的影响分别达到0.92,0.22,0.21和0.18 mm;随着LEO卫星轨道高度的增加,HOI延迟对LEO卫星简化动力学POD的影响减小。 展开更多
关键词 LEO卫星 HOI延迟 简化动力学POD 轨道高度
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基于信号响应分析模型的金属结构损伤导波检出概率
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作者 王莉 杨宇 +3 位作者 刘国强 王霞光 李嘉欣 任一鹏 《振动与冲击》 EI CSCD 北大核心 2024年第2期32-41,186,共11页
飞机结构损伤导波在线监测技术作为一种新颖的无损检测手段,为了真正实现该技术在结构运营维护过程中的视情维护,必须明确其结构损伤检出概率(probability of detection,POD),以指导结构检查维修方案的制定。提出了一种基于信号响应分... 飞机结构损伤导波在线监测技术作为一种新颖的无损检测手段,为了真正实现该技术在结构运营维护过程中的视情维护,必须明确其结构损伤检出概率(probability of detection,POD),以指导结构检查维修方案的制定。提出了一种基于信号响应分析模型的结构损伤导波POD计算方法,该方法通过构建在线导波监测信号的损伤指数与裂纹长度间的对应关系,得到结构损伤POD的统计计算模型,并分析了拟合参数的不确定性对计算模型的影响,构建了不同置信度下的导波POD计算模型。通过开展金属开孔和搭接结构疲劳裂纹导波监测试验,验证了该方法的有效性。试验结果表明,损伤指数类型、对应关系拟合函数和传感器监测方案均对结构损伤导波POD具有影响,且在95%置信度90%POD下金属开孔和搭接结构的可检裂纹长度分别约为2.6 mm和9.5 mm。 展开更多
关键词 结构健康监测 导波 检出概率(POD) 金属 疲劳裂纹
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Experimental Study and Thermal Modelling of Cocoa Shell Convective Drying in an Indirect Solar Dryer
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作者 Siaka Touré Adjo Christelle Ogo Modibo Sidibé 《Modeling and Numerical Simulation of Material Science》 2024年第2期69-78,共10页
The concern of the present work is the convective drying of empty cocoa shells in an indirect solar dryer. Some drying experiments, using one sample, were carried out. During the experiments, the sample is introduced ... The concern of the present work is the convective drying of empty cocoa shells in an indirect solar dryer. Some drying experiments, using one sample, were carried out. During the experiments, the sample is introduced in the drying chamber. Then at steady time intervals, the sample is withdrawn from the drying chamber, for a rapid weighing. After each weighing, the sample is reintroduced in the dryer. At each time interval, the ambient temperature of the drying chamber and its relative humidity γ are measured by a thermo-hygrometer. From the experimental data, a theoretical determination of the moisture evaporated from the product was performed and a good agreement was found between the theoretical and experimental values, confirmed by the value of the RMSE. Those calculations used the constants in the Nusselt number found in literature. Then those constants were evaluated again, to get new values more suitable with the experimental data. The dimensionless numbers of Nusselt, Grashof and Prandtl were calculated. That allowed the calculation of the average value of the Nusselt number. The average convective heat transfer coefficient was determined. 展开更多
关键词 Shells of Cocoa pods Indirect Solar Dryer Moisture Evaporated Constants of the Nusselt Number Convective Heat Transfer Coefficient
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干旱胁迫对玉米幼苗ROS和POD的影响
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作者 王庆云 丁秀 《农业科技通讯》 2024年第3期80-82,共3页
山西省内市场上销售的玉米品种多为抗旱品种,为了更好地区分不同品种之间的差异,本研究选取8个玉米品种为试验材料,采用土培的方式,人工控制水量模拟干旱,研究干旱胁迫下不同品种玉米幼苗的活性氧(ROS)和过氧化物酶(POD)的变化。采用双... 山西省内市场上销售的玉米品种多为抗旱品种,为了更好地区分不同品种之间的差异,本研究选取8个玉米品种为试验材料,采用土培的方式,人工控制水量模拟干旱,研究干旱胁迫下不同品种玉米幼苗的活性氧(ROS)和过氧化物酶(POD)的变化。采用双抗体夹心法测定ROS的含量,采用愈创木酚法测定POD活性。结果表明,干旱胁迫下各品种玉米幼苗ROS含量全部上升,其中大丰26、大丰30和并单16的ROS含量增加不显著,其余品种增加显著;干旱胁迫诱导大丰26和大丰30的POD活性显著上升,其余品种的POD活性变化不显著。分析ROS和POD活性指标变化可以看出,与其余7个品种相比,大丰30的抗旱能力更强。 展开更多
关键词 玉米幼苗 干旱胁迫 POD ROS
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基于POD方法的EPR燃料棒流致振动特性分析 被引量:2
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作者 闵光云 冯琳娜 姜乃斌 《力学学报》 EI CAS CSCD 北大核心 2024年第3期659-669,共11页
EPR(European pressurized reactor)燃料棒相比M310燃料棒的棒长更长,导致其频率降低、幅值增大,在冷却剂的作用下,会加剧格架与棒束之间微动磨损(grid-to-rod fretting,GTRF),进而造成放射性物质的泄漏.将EPR燃料棒简化为3D梁模型,将... EPR(European pressurized reactor)燃料棒相比M310燃料棒的棒长更长,导致其频率降低、幅值增大,在冷却剂的作用下,会加剧格架与棒束之间微动磨损(grid-to-rod fretting,GTRF),进而造成放射性物质的泄漏.将EPR燃料棒简化为3D梁模型,将刚凸和弹簧对燃料棒的约束等效为弹性约束,将带格架的燃料棒简化为多跨连续简支梁模型,然后基于ANSYS-APDL建立了EPR燃料棒的有限元模型.阐述了湿模态分析和湍流激振响应分析的基本原理,整理了12个格架失效工况,系统地研究了格架失效对湿模态和湍流激振响应的影响.针对EPR燃料棒流致振动问题,提出了采用本征正交分解(proper orthogonal decomposition,POD)原理分析EPR燃料棒流致振动特性的方法,通过对快照矩阵进行POD分解生成投影子空间,将湍流激振响应投影到子空间进行模型降阶,最后在物理空间快速地重构湍流激振响应.结果表明:格架失效会导致频率降低,且湍流激振响应的幅值会在格架失效处增大;当格架失效使得EPR燃料棒模型成为悬臂梁结构时,湍流激振响应最大;前2阶POD降阶模型基本能快速重构燃料棒的湍流激振响应,且误差非常小.文章的研究将有助于核反应堆工程的优化和设计. 展开更多
关键词 流致振动 POD方法 EPR燃料棒 模态分析 格架失效
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多孔陶瓷板预混火焰热声振荡多模态转换实验研究
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作者 王阿彪 季晨振 +3 位作者 宋秀阳 王萌铭 潘登 朱彤 《燃烧科学与技术》 CAS CSCD 北大核心 2024年第6期609-618,共10页
针对多孔陶瓷板甲烷-空气预混火焰,搭建了两端开口的Rijke管实验台,研究了当量比对多模态转换的影响,分析了不同自激振荡模态下火焰的不稳定特征.实验结果表明,当量比的变化会引起自激振荡模态转换.当燃烧功率固定为0.96 kW,增加空气流... 针对多孔陶瓷板甲烷-空气预混火焰,搭建了两端开口的Rijke管实验台,研究了当量比对多模态转换的影响,分析了不同自激振荡模态下火焰的不稳定特征.实验结果表明,当量比的变化会引起自激振荡模态转换.当燃烧功率固定为0.96 kW,增加空气流量,当量比从1.17降低到0.71时,管内压力振荡主频由163 Hz迁移至355 Hz.利用格林函数法计算Rijke管的声学特征频率,表明实验测试的两组自激振荡频率分别为Rijke管的一阶和二阶声学特征频率.不同当量比下火焰平均热释放率图像表明,高当量比火焰更易与系统低阶振荡频率耦合,这是因为此时火焰长度较高,且预混气体流速较慢,对应对流延迟时间较长.使用相平均和本征正交分解方法得到了不同振荡频率下的振荡模态,低频振荡以轴向振荡为主,高频振荡以频闪振荡为主. 展开更多
关键词 燃烧不稳定 热声振荡 模态转换 格林函数法 POD分解
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异源表达甜菜BvHSP18.2基因增强拟南芥对镉胁迫的耐受性研究
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作者 仲维婷 张琼 +1 位作者 兴旺 刘大丽 《中国农学通报》 2024年第29期14-20,共7页
为进一步分析和验证甜菜BvHSP18.2基因(LOC104903994)受镉胁迫调控的功能,本研究用RTPCR技术克隆了甜菜BvHSP18.2基因,并通过植物表达载体构建以及拟南芥的遗传转化,测得异源表达目的基因的拟南芥植株在不同浓度镉胁迫下的表型及生理变... 为进一步分析和验证甜菜BvHSP18.2基因(LOC104903994)受镉胁迫调控的功能,本研究用RTPCR技术克隆了甜菜BvHSP18.2基因,并通过植物表达载体构建以及拟南芥的遗传转化,测得异源表达目的基因的拟南芥植株在不同浓度镉胁迫下的表型及生理变化数据。研究结果表明,随着镉胁迫浓度的增加,异源表达BvHSP18.2基因的拟南芥无论在根长还是鲜重方面均具有优势:50μmol/L镉胁迫下平均根长相差最大,为1.1 cm,600μmol/L镉胁迫下平均鲜重相差最大,为0.015 g。同时,BvHSP18.2基因的过表达可有效提高拟南芥体内SOD和POD活性,300μmol/L镉胁迫下SOD活性最高,为657.7266953 U/g;600μmol/L镉胁迫下POD活性最高,为野生型拟南芥的1.91倍。BvHSP18.2基因的过表达增强了拟南芥在镉胁迫下的耐受性,推测该基因在植物对镉胁迫的适应机制中具有重要的作用。 展开更多
关键词 甜菜 拟南芥 BvHSP18.2基因 异源表达 镉胁迫 功能分析 基因克隆 SOD活性 POD活性 耐受性 遗传转化
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Construction and Application of a Regional Kilometer-Scale Carbon Source and Sink Assimilation Inversion System(CCMVS-R) 被引量:1
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作者 Lifeng Guo Xiaoye Zhang +8 位作者 Junting Zhong Deying Wang Changhong Miao Licheng Zhao Zijiang Zhou Jie Liao Bo Hu Lingyun Zhu Yan Chen 《Engineering》 SCIE EI CAS CSCD 2024年第2期263-275,共13页
CO_(2)is one of the most important greenhouse gases(GHGs)in the earth’s atmosphere.Since the industrial era,anthropogenic activities have emitted excessive quantities of GHGs into the atmosphere,resulting in climate ... CO_(2)is one of the most important greenhouse gases(GHGs)in the earth’s atmosphere.Since the industrial era,anthropogenic activities have emitted excessive quantities of GHGs into the atmosphere,resulting in climate warming since the 1950s and leading to an increased frequency of extreme weather and climate events.In 2020,China committed to striving for carbon neutrality by 2060.This commitment and China’s consequent actions will result in significant changes in global and regional anthropogenic carbon emissions and therefore require timely,comprehensive,and objective monitoring and verification support(MVS)systems.The MVS approach relies on the top-down assimilation and inversion of atmospheric CO_(2)concentrations,as recommended by the Intergovernmental Panel on Climate Change(IPCC)Inventory Guidelines in 2019.However,the regional high-resolution assimilation and inversion method is still in its initial stage of development.Here,we have constructed an inverse system for carbon sources and sinks at the kilometer level by coupling proper orthogonal decomposition(POD)with four-dimensional variational(4DVar)data assimilation based on the weather research and forecasting-greenhouse gas(WRF-GHG)model.Our China Carbon Monito ring and Verification Support at the Regional level(CCMVS-R)system can continuously assimilate information on atmospheric CO_(2)and other related information and realize the inversion of regional and local anthropogenic carbon emissions and natural terrestrial ecosystem carbon exchange.Atmospheric CO_(2)data were collected from six ground-based monito ring sites in Shanxi Province,China to verify the inversion effect of regio nal anthropogenic carbon emissions by setting ideal and real experiments using a two-layer nesting method(at 27 and 9 km).The uncertainty of the simulated atmospheric CO_(2)decreased significantly,with a root-mean-square error of CO_(2)concentration values between the ideal value and the simulated after assimilation was close to 0.The total anthropogenic carbon emissions in Shanxi Province in 2019 from the assimilated inversions were approximately 28.6%(17%-38%)higher than the mean of five emission inventories using the bottomup method,showing that the top-down CCMVS-R system can obtain more comprehensive information on anthropogenic carbon emissions. 展开更多
关键词 CCMVS-R Regional carbon assimilation system Anthropogenic carbon emissions CO_(2) POD 4DVar
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Gappy POD算法重构储能电池组核心温度及与BP神经网络预测能力对比
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作者 苑清扬 薛珂 +1 位作者 张博 兰天 《工程科学学报》 EI CSCD 北大核心 2024年第1期166-177,共12页
储能电池组中电池核心温度的实时监控对于防控电池热失控有着重要的意义.为克服工业实际中电池组内部无法布置多温度测点导致的温度数据获取不全面等问题,本文将Gappy POD重构算法引入储能电池核心温度实时监控问题中,通过监测电池组表... 储能电池组中电池核心温度的实时监控对于防控电池热失控有着重要的意义.为克服工业实际中电池组内部无法布置多温度测点导致的温度数据获取不全面等问题,本文将Gappy POD重构算法引入储能电池核心温度实时监控问题中,通过监测电池组表面温度预测内部核心温度.通过搭建简化的拟储能电池实验台模拟电池温升,测试了Gappy POD算法在工况平稳变化和工况剧烈变化条件下的稳定性和对核心温度的实时重构能力;对比了Gappy POD算法的重构能力和BP神经网络(Back propagation neural network)的预测能力,并探究了Gappy POD算法和BP神经网络在不同大小的数据库训练条件下的重构预测能力.研究表明,Gappy POD重构算法具有高预测精度、稳定性强并且对数据库数据量依赖性低等优势,为算法在储能电池热管理中的实际应用提供了基础. 展开更多
关键词 Gappy POD BP神经网络 储能电池 热管理 核心温度预测
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灌木辣椒(Capsicum frutescens)抗象耳豆根结线虫的组织学及生理生化特征分析
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作者 陈梅红 黄银香 +4 位作者 林珑 高畅 涂容生 朱婕 刘子记 《热带作物学报》 CSCD 北大核心 2024年第9期1902-1911,共10页
象耳豆根结线虫(Meloidogyne enterolobii)寄主范围广,侵染能力强,已发展为根结线虫(Meloidogyne spp.)中最具破坏性的1个种。海南地区辣椒生产受象耳豆根结线虫影响较大。利用作物本身的抗性来防治该病害是比较绿色、经济、环保的办法... 象耳豆根结线虫(Meloidogyne enterolobii)寄主范围广,侵染能力强,已发展为根结线虫(Meloidogyne spp.)中最具破坏性的1个种。海南地区辣椒生产受象耳豆根结线虫影响较大。利用作物本身的抗性来防治该病害是比较绿色、经济、环保的办法。前期,本研究团队已从30份本地灌木辣椒(Capsicumfrutescens)资源中筛选出1份抗病种质CF25。为更好地利用该种质开展抗病育种工作,加深对其抗病机理的理解,本研究对抗病种质CF25和感病种质CF29接种象耳豆根结线虫,通过酸性品红染色和石蜡切片等方法,结果发现在根结线虫侵入量方面,CF25的线虫侵入量比CF29少;在根结线虫发育形态方面,CF25中线虫发育比CF29缓慢,且出现雌虫发育不良的现象;在根系解剖结构方面,CF25巨细胞中的内容物逐渐减少,出现空洞化现象。为初步探索CF25抗根结线虫的生理基础,对CF25和CF29进行过氧化物酶(POD)和苯丙氨酸解氨酶(PAL)活性测定。结果显示,接种后多数时间点CF25的POD和PAL活性显著高于CF29。综上所述,从组织学角度来看,灌木辣椒资源CF25对象耳豆根结线虫的抗性主要体现在抗侵入和限制取食两方面;CF25巨细胞内容物的减少可能抑制了根结线虫的进食,从而导致其发育缓慢且不良;从生理生化角度来看,CF25较高的POD活性可能有利于清除根结线虫侵染导致的活性氧积累。此外,较高的POD和PAL活性可能导致包括木质素在内的更多苯丙烷类次生代谢产物的生成,从而提高了CF25的抗病性。本研究分析了灌木辣椒资源CF25抗象耳豆根结线虫的组织学和生理生化基础,可为后续深入探究灌木辣椒抗象耳豆根结线虫机理提供依据。 展开更多
关键词 象耳豆根结线虫 抗性 灌木辣椒 组织学 POD PAL
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基于声子晶体的声发射波源检测概率研究 被引量:1
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作者 李红豫 曾祥兴 张璐 《振动与冲击》 EI CSCD 北大核心 2024年第7期75-83,共9页
声发射(acoustic emission,AE)检测就是利用采集和分析声发射现象所产生的信号从而实现对材料进行无损评价的技术,该技术具有实时监测并定位破坏源的能力但是由于检测过程中声发射源信号未知,因此评价检测可靠性的检测概率(probability ... 声发射(acoustic emission,AE)检测就是利用采集和分析声发射现象所产生的信号从而实现对材料进行无损评价的技术,该技术具有实时监测并定位破坏源的能力但是由于检测过程中声发射源信号未知,因此评价检测可靠性的检测概率(probability of detection,POD)研究仍然是空白。进一步来说,在利用声发射监测损伤过程时,声发射波源直接决定其检测结果的可靠性,因此波源的检测概率可以成为量化声发射检测有效性的一个重要指标。为了确定声发射波源的检测概率,利用声子晶体(phononic crystals,PCs)的特性,通过部署声子晶体形成物理带隙,滤除噪声信号,从而获得铝合金试件在紧凑拉伸试验下由于疲劳裂缝活动而引起的声发射信号,最终确定声发射源的检测概率及其影响因素。结果表明,检测概率会随着疲劳裂缝扩展而提高,但裂缝长度达到一定值后开始下降,最终趋于一个平稳值,另外通过设置阈值和选择适当的滤波器,能有效提高检测概率,保证声发射评价结构损伤的有效性。该研究对声发射源识别和检测可靠性评价具有重要意义。 展开更多
关键词 声发射(AE) 检测概率(POD) 声子晶体 疲劳裂缝
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聚噁二唑纱线的还原染料染色
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作者 丁致家 夏亚辉 +2 位作者 吴之瑜 钱俊 曹根阳 《印染》 CAS 北大核心 2024年第2期21-24,共4页
聚噁二唑(POD)纤维存在光稳定性不足、耐日晒色牢度差的问题,选用日晒牢度优异的3种不同颜色的还原染料对POD纱线进行染色试验,研究其染色性能及色牢度。研究表明,3%(omf)还原红/黄/蓝染料染色POD纱线的K/S值分别达到6.5/9.2/11.4,耐日... 聚噁二唑(POD)纤维存在光稳定性不足、耐日晒色牢度差的问题,选用日晒牢度优异的3种不同颜色的还原染料对POD纱线进行染色试验,研究其染色性能及色牢度。研究表明,3%(omf)还原红/黄/蓝染料染色POD纱线的K/S值分别达到6.5/9.2/11.4,耐日晒色牢度、耐干/湿摩擦色牢度均可达到3~4级,耐汗渍色牢度、耐水洗色牢度均可达到4~5级。同时,染色对POD纱线的热学性能和力学性能影响不显著。 展开更多
关键词 还原染料 染色 耐日晒色牢度 染色性能 POD纱线
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POD和DMD方法对燃料棒流致振动特性的分析
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作者 闵光云 姜乃斌 《原子能科学技术》 EI CAS CSCD 北大核心 2024年第10期2162-2172,共11页
燃料棒的流致振动是造成燃料失效和反应堆停堆的重要因素之一,研究其流致振动机理非常必要。本文建立了燃料棒的高保真有限元模型,基于ANSYS Batch和随机振动理论批量计算了不同支撑刚度下燃料棒的流致振动响应,并搭建了1个流致振动响... 燃料棒的流致振动是造成燃料失效和反应堆停堆的重要因素之一,研究其流致振动机理非常必要。本文建立了燃料棒的高保真有限元模型,基于ANSYS Batch和随机振动理论批量计算了不同支撑刚度下燃料棒的流致振动响应,并搭建了1个流致振动响应数据库。该数据库采用不同支撑刚度值来模拟和检查燃料棒可能遇到的情况。基于数据库组装快照矩阵,采用两种数据驱动方法(POD方法和DMD方法)搭建了1个高保真降阶模型(ROM),该ROM能够实现流致振动响应的快速重构。对比了POD方法和DMD方法重构燃料棒流致振动响应的效果以及各自的优点和缺点。研究发现:使用相同数量的模态重构燃料棒的流致振动响应时,POD方法的重构效果优于DMD方法;基于相同数量的模态重构时,刚度为1 N/mm的重构效果最差,这主要是因为刚度越小,频率越小,系统的振幅越大,需要更多数量的模态才能捕捉大幅振动带来的影响;DMD方法不仅能够高效地重构燃料棒的振动响应,还能够判断每个DMD模态的稳定性。 展开更多
关键词 POD DMD 流致振动 模态 燃料棒
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