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混合动力车辆加速工况发动机介入抖动的分析与优化

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清华大学学报（自然科学版） 2024年第3期64卷 552-561页

作者：廉玉波刘云卿 Zhang charles 张荣荣比亚迪汽车工业有限公司深圳518118

混合动力车辆在电池电量较低、城市路况拥堵的情况下行驶时,为保持电池电量,发动机会频繁地启动发电,从而引起整车抖动问题。该文建立了混动总成发动机介入抖动的物理模型,采用仿真和实验相结合的方法,研究了混动车加速过程中发动机介... 详细信息

混合动力车辆在电池电量较低、城市路况拥堵的情况下行驶时,为保持电池电量,发动机会频繁地启动发电,从而引起整车抖动问题。该文建立了混动总成发动机介入抖动的物理模型,采用仿真和实验相结合的方法,研究了混动车加速过程中发动机介入瞬间的抖动产生及路径传递机理。结果表明:发动机介入瞬间的抖动出现在发动机点火之前的集成启动发电一体化发电机(integrated starter generator, ISG)倒拖发动机阶段,其抖动水平由第一循环缸压峰值大小决定;混动总成瞬时刚体模态和传动系扭转模态耦合作用提高了发动机介入抖动水平,并将抖动通过动力总成悬置传递至车身。基于该结论,提出了传动系和动力总成模态解耦原则与优化悬置限位结构2项优化措施,并结合整车测试验证了所提措施有效。

关键词：混合动力发动机介入抖动第一循环缸压模态耦合动力总成悬置

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Numerical modelling of reinforced concrete flexural members strengthened using textile reinforced mortars

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Frontiers of Structural and Civil Engineering 2023年第4期17卷 649-668页

作者： Naveen Revanna charles k.S.Moy Department of Civil Engineering Xi’an Jiaotong-Liverpool UniversitySuzhou 215123China

Externally bonded(EB)and near-surface mounted(NSM)bonding are two widely adopted and researched strengthening methods for reinforced-concrete *** composite substrates are easy to reach and repair using appropriate surface treatments,whereas NSM techniques can be easily applied to the soffit and concrete member *** EB bonded fiber-reinforced polymer(FRP)technique has a significant drawback:combustibility,which calls for external protective agents,and textile reinforced mortar(TRM),a class of EB composites that is noncombustible and provides a similar functionality to any EB FRP-strengthened *** study employs a finite element analysis technique to investigate the failing failure of carbon textile reinforced mortar(CTRM)-strengthened reinforced concrete *** principal objective of this numerical study was to develop a finite element model and validate a set of experimental data in existing literature.A set of seven beams was modelled and calibrated to obtain concrete damage plasticity(CDP)*** predicted results,which were in the form of load versus deflection,load versus rebar strain,tensile damage,and compressive damage patterns,were in good agreement with the experimental ***,a parametric study was conducted to verify the applicability of the numerical model and study various influencing factors such as the concrete strength,internal reinforcement,textile roving spacing,and externally-applied load *** ultimate load and deflection of the predicted finite element results had a coefficient of variation(COV)of 6.02%and 5.7%,respectively.A strain-based numerical comparison with known methods was then conducted to investigate the debonding *** developed finite element model can be applied and tailored further to explore similar TRM-strengthened beams undergoing debonding,and the preventive measures can be sought to avoid premature debonding.

关键词： fiber reinforced polymer textile reinforced mortar finite element analysis concrete damage plasticity calibration and validation parametric study

Aging impairs the osteocytic regulation of collagen integrity and bone quality

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Bone Research 2024年第1期12卷 78-94页

作者： charles A.Schurman Serra kaya Neha Dole Nadja M.Maldonado Luna Natalia Castillo Ryan Potter Jacob P.Rose Joanna Bons Christina D.king Jordan B.Burton Birgit Schilling Simon Melov Simon Tang Eric Schaible Tamara Alliston Department of Orthopaedic Surgery University of CaliforniaSan FranciscoCA 94143USA UC Berkeley/UCSF Graduate Program in Bioengineering San FranciscoCA 94143USA Buck Institute for Research on Aging NovatoCA 94945USA Washington University in St Louis Department of OrthopedicsSt.LouisMO 63130USA Advanced Light Source Lawrence Berkeley National LaboratoryBerkeleyCA 94720USA

Poor bone quality is a major factor in skeletal fragility in elderly *** molecular mechanisms that establish and maintain bone quality,independent of bone mass,are unknown but are thought to be primarily determined by *** hypothesize that the age-related decline in bone quality results from the suppression of osteocyte perilacunar/canalicular remodeling(PLR),which maintains bone material *** examined bones from young and aged mice with osteocyte-intrinsic repression of TGFβsignaling(TβRII^(ocy−/−))that suppresses *** control aged bone displayed decreased TGFβsignaling and PLR,but aging did not worsen the existing PLR suppression in male TβRII^(ocy−/−)*** relationship impacted the behavior of collagen material at the nanoscale and tissue scale in macromechanical *** effects of age on bone mass,density,and mineral material behavior were independent of osteocytic TGFβ.We determined that the decline in bone quality with age arises from the loss of osteocyte function and the loss of TGFβ-dependent maintenance of collagen integrity.

关键词： maintain primarily integrity

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黄龙病侵染增强沙糖橘对柑橘木虱吸引作用机制的初步研究

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应用昆虫学报 2024年第2期61卷 390-400页

作者：黄克志杨玉枝闫梦梦 George Andrew charles BEATTIE 徐长宝岑伊静华南农业大学柑橘黄龙病研究室绿色农药全国重点实验室广东岭南职业技术学院 School of Science and Health Western Sydney University

【目的】黄龙病是柑橘最严重的传染性病害，柑橘木虱Diaphorina citri kuwayama是黄龙病的媒介昆虫。与健康橘树相比，感染黄龙病的橘树对木虱的吸引作用显著增强，本研究目的是探明病树挥发物的改变是否与此现象有关。【方法】在前期... 详细信息

【目的】黄龙病是柑橘最严重的传染性病害，柑橘木虱Diaphorina citri kuwayama是黄龙病的媒介昆虫。与健康橘树相比，感染黄龙病的橘树对木虱的吸引作用显著增强，本研究目的是探明病树挥发物的改变是否与此现象有关。【方法】在前期分析健康和染病沙糖橘Citrus reticulate ***. Shatangju嫩梢挥发物成分变化的基础上，分别在室内外测定部分差异较大的化合物单体标样及其混合物对柑橘木虱的吸引效果。【结果】雌虫对α-蒎烯（1μL/mL）、γ-萜品烯（0.01μL/mL）和芳樟醇（0.1μL/mL）具有显著的正趋性，但对柠檬烯各浓度均未表现出明显的趋性；雄虫对4种单体标样所有浓度均未表现出显著的趋性。将各种化合物按其有效浓度混合后，雌虫对6种混合物均有显著的正趋性，其中，对γ-萜品烯（0.2μL/mL）+α-蒎烯（0.8μL/mL）+芳樟醇（0.3μL/mL）具有极显著正趋向选择；雄虫对4种混合物有显著的正趋性。将化合物单体及其混合物作为诱剂，在九里香Murraya paniculata L.上测定其诱集效果。结果表明，单一物质均无显著效果，但15种混合物中有5种诱到的木虱数量显著多于对照。将其中3种混合物γ-萜品烯（20μL/mL）+α-蒎烯（80μL/mL）+芳樟醇（30μL/mL）、γ-萜品烯（2μL/mL）+α-蒎烯（8μL/mL）+芳樟醇（3μL/mL）和γ-萜品烯（20μL/mL）+芳樟醇（30μL/mL）在橘园进行测试，结果表明，3种诱剂诱到的木虱数量均显著增加。【结论】α-蒎烯、γ-萜品烯含量增加可能是沙糖橘病树对木虱吸引作用增强的部分原因，这些物质有望用于制备柑橘木虱的引诱剂，但其最佳配比还有待进一步研究。

关键词：柑橘木虱黄龙病沙糖橘寄主挥发物引诱剂

The siphonic energy transfer between hot solar wind and cold martian ionosphere through open magnetic flux rope

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Fundamental Research 2024年第4期4卷 882-889页

作者： Xiaojun Xu Lou-Chuang Lee Qi Xu Qing Chang Jing Wang Ming Wang Shaosui Xu Christian Mosti charles J.Farrugia Xing Wang Yudong Ye Zilu Zhou Lei Luo Peishan He Shaoguan Cheng State key Laboratory of Lunar and Planetary Sciences Macao University of Science and TechnologyMacao 999078China CNSA Macao Center for Space Exploration and Science Macao 999078China Institute of Earth Science Academia SinicaTaipei 115029China Institute of Space Science and Applied Technology Harbin Institute of TechnologyShenzhen 518000China Planetary Environmental and Astrobiological Research Laboratory(PEARL) School of Atmospheric SciencesSun Yat-sen UniversityZhuhai 519000China Nanjing University of Information Science and Technology Nanjing 210000China Space ScienceLaboratory Universityof CaliforniaBerkeleyCA94320USA Space Research Institute Austrian Academy of SciencesGraz 8010Austria University of New Hampshire NH 03824USA

A mechanism for energy transfer from the solar wind to the Martian ionosphere through open magnetic flux rope is proposed based on the observations by Mars Atmosphere and Volatile EvolutioN(MAVEN).The satellite was located in the dayside magnetosheath at an altitude of about 70o km above the northern *** between the hot solar wind protons and the cold heavy ions/neutrals in the subsolar region can cool the protons and heat the heavy *** a result,the magnetosheath protons are siphoned into the ionosphere due to the thermal pressure gradient of protons and the heated heavy ions escape along the open magnetic field *** direct collisions in the lower-altitude region were not detected,this physical process is demonstrated by MAVEN measurements of enhanced proton density,decreased proton temperature and oppositely directed motions of hot and cool protons within the flux rope,which are very different from the observational features of the flux transfer events near the Earth's *** mechanism could universally exist in many contexts where a collisionless plasma region is connected to a collisional plasma *** reconstructing the magnetic geometry and the cross-section of the flux rope using the Grad-Shafranov technique,the ion loss rates are quantitatively estimated to be on the order of 1023 s-l,which is much higher than previously estimated.

关键词： Mars Flux rope Solarwind Ionosphere Ion loss

Assessing Community Health Interventions in Reducing Infant and Child Mortality in the Southeastern Benin

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Open Journal of Preventive Medicine 2024年第1期14卷 17-28页

作者： charles Sossa Jerome Daouda Gbadamassi Lamidhi Salami Colette Azandjeme Clémence Metonnou Moussiliou N. Paraiso Health Promotion Department Regional Institute of Public Health University of Abomey-Calavi Ouidah Benin National Medical and Sanitary Institute University of Abomey-Calavi Cotonou Benin Health Policy and Systems Department Regional Institute of Public Health University of Abomey-Calavi Ouidah Benin

Background: To reduce infant and child mortality in Benin, a package of high-impact interventions per healthcare level was implemented in 2009. This study aimed to assess the quality of community-based health interventions in reducing infant and child mortality within the municipality of Pobè in southeastern Benin. Methods: This was a cross-sectional evaluative study carried out in November 2021 focused on children aged 0 - 59 months, their mothers, health workers, community facilitators, community health workers and the Town Hall health focal point. Mothers and their children were targeted by cluster sampling, and exhaustive selection was used to recruit all other participants. Predetermined scores based on rating criteria were used to assess the quality of community health interventions using the “input, process and outcome” of Donabedian approach. Results: Over 300 mother-child couples, 46 community health workers, 7 health agents, 1 community facilitator and 1 health focal point from Pobè town hall were surveyed. Intervention quality was judged as “average”, with a score of 73.80%. The “inputs” and “outcomes” components were the weakest links. Conclusion: Improving access to the inputs needed by community health workers can enhance the quality of PIHI interventions.

关键词： Community-Based Interventions Infant and Child Mortality Benin

Microbiological Quality of Cyperus esculentus L. Products Sold in Ouagadougou and Bobo Dioulasso (Burkina Faso)

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Open Journal of Applied Sciences 2024年第3期14卷 635-642页

作者： Zénabou Semdé Passinguemsin Alice Sonia Tiendrebeogo Bahanla Edwige Oboulbiga charles Parkouda Hagrétou Sawadogo Lingani Laboratoire des Sciences et Technologies des Aliments et Nutrition Département technologie alimentaire IRSAT CNRST Ouagadougou Burkina Faso

This study aimed to assess the microbiological quality of tiger nut (Cyperus esculentus L.) products sold in Ouagadougou and Bobo Dioulasso. The microbial load of tubers and tiger nut milk was determined using ISO 4833-1 (2003) standard (total mesophilic aerobic flora), NF ISO 7954 (1998) standard (yeasts and molds), and ISO 4832 (2006) standard (total coliforms, thermotolerant coliforms). The results showed that tiger nut tubers had an average microbial load between 4.86 ± 7.03 × 106 UFC/g and 1.82 ± 2.30 × 107 UFC/g for total mesophilic aerobic flora, from 4.34 ± 10.6 × 105 UFC/g to 3.52 ± 4.54 × 106 UFC/g for yeasts and molds, from 2.23 ± 2.25 × 105 UFC/g to 1.41 ± 2.16 × 105 UFC/g for total coliforms and from 1.83 ± 2.03 × 105 UFC/g to 7.0 ± 10.8 × 104 CFU/g for thermotolerant coliforms. For tiger nut milk samples, the average microbial load varied from 3.48 ± 2.98 × 106 CFU/g to 2.80 ± 5.69 × 107 CFU/g for total mesophilic aerobic flora, from 5.00 ± 7.21 × 104 CFU/g to 1.88 ± 3.31 × 105 CFU/g for yeasts and molds, from 4.58 ± 10.4 × 104 CFU/g to 6.31 ± 9.17 × 105 CFU/g for total coliforms and 7.00 ± 7.00 × 103 CFU/g to 2.87 ± 5.86 × 105 CFU/g for thermotolerant coliforms. This study revealed that the tubers and tiger nut milk sold in Ouagadougou and Bobo Dioulasso had a high microbial load which could lead to the degradation of these products and food poisoning for consumers.

关键词： Cyperus esculentus L. Tiger Nut Tubers Tiger Nut Milk Microbiological Quality

Estimating the Yield Loss of Winter Wheat from Drought in the United States Southern Plains Region as Influenced by El Niño-Southern Oscillation (ENSO)

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Agricultural Sciences 2024年第9期15卷 1018-1034页

作者： Prem Woli Gerald R. Smith charles R. Long Francis M. Rouquette, Jr. Texas A&M AgriLife Research Center Overton USA

Wheat (Triticum aestivum L.) production is a major economic activity in most regional and rural areas in the Southern Plains, a semi-arid region of the United States. This region is vulnerable to drought and is projected to experience a drier climate in the future. Since the interannual variability in climate in this region is linked to an ocean-atmospheric phenomenon, called El Niño-Southern Oscillation (ENSO), droughts in this region may be associated with ENSO. Droughts that occur during the critical growth phases of wheat can be extremely costly. However, the losses due to an impending drought can be minimized through mitigation measures if it is predicted in advance. Predicting the yield loss from an imminent drought is crucial for stakeholders. One of the reliable ways for such prediction is using a plant physiology-based agricultural drought index, such as Agricultural Reference Index for Drought (ARID). This study developed ENSO phase-specific, ARID-based models for predicting the drought-induced yield loss for winter wheat in this region by accounting for its phenological phase-specific sensitivity to drought. The reasonable values of the drought sensitivity coefficients of the yield model for each ENSO phase (El Niño, La Niña, or Neutral) indicated that the yield models reflected reasonably well the phenomena of water stress decreasing the winter wheat yields in this region during different ENSO phases. The values of various goodness-of-fit measures used, including the Nash-Sutcliffe Index (0.54 to 0.67), the Willmott Index (0.82 to 0.89), and the percentage error (20 to 26), indicated that the yield models performed fairly well at predicting the ENSO phase-specific loss of wheat yields from drought. This yield model may be useful for predicting yield loss from drought and scheduling irrigation allocation based on the phenological phase-specific sensitivity to drought as impacted by ENSO.

关键词： ARID Drought Drought Index ENSO El Niño Growth-Stage Model Phenological-Phase Prediction Semi-Arid Wheat Yield Loss

Sc元素添加对双辊铸轧Al−Cu−Li−Mg−Zr基合金热处理的影响

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Transactions of Nonferrous Metals Society of China 2024年第6期34卷 1759-1773页

作者： Rostislav kRÁLÍk Barbora kŘIVSkÁ Lucia BAJTOŠOVÁ Mykhailo STOLBCHENkO Mirko SCHAPER Olexandr GRYDIN Miroslav CIESLAR Department of Physics of Materials Faculty of Mathematics and PhysicsCharles UniversityKe Karlovu 512116PragueCzech Republic Department of Materials Science Faculty of Mechanical EngineeringUniversity of PaderbornWarburger Straße 10033098PaderbornGermany

提出制备含Sc的Al−Cu−Li−Mg−Zr基合金带材的工艺方案。即先采用双辊铸轧技术制备近净形状的3 mm厚带材,再对其进行均匀化/固溶处理。研究两种Al−Cu−Li−Mg−Zr基双辊铸轧合金,其中一种添加质量分数为0.17%的Sc,另一种未添加Sc。两种合金... 详细信息

提出制备含Sc的Al−Cu−Li−Mg−Zr基合金带材的工艺方案。即先采用双辊铸轧技术制备近净形状的3 mm厚带材,再对其进行均匀化/固溶处理。研究两种Al−Cu−Li−Mg−Zr基双辊铸轧合金,其中一种添加质量分数为0.17%的Sc,另一种未添加Sc。两种合金均先在300℃下退火30 min,然后在450℃下退火30 min以及530℃下退火30 min,随后进行室温水淬。前两段退火后组织中生成了细小、弥散的Al_(3)Zr/Al_(3)(Sc,Zr)颗粒。最后的退火步骤起到了均匀化/固溶处理的作用。双辊铸轧材料的细小晶粒结构使含有主要合金元素的原始颗粒在较短的退火时间内溶解。缩短保温时间可以限制表面层中Li的耗尽和Al_(3)Zr/Al_(3)(Sc,Zr)弥散相的明显粗化。铸态含Sc材料已经具有明显细小的晶粒结构,而经均匀化/固溶处理后生成的Al_(3)(Sc,Zr)弥散相抑制了晶粒在高温下发生粗化。在后续180℃下时效处理后,形成了θʹ(Al_(2)Cu)、T1(Al_(2)CuLi)和S'(Al_(2)CuMg)强化相。在峰值时效状态下,屈服强度提高了200 MPa,这一数值与类似直接冷却铸造材料的相当,从而证实了所提方案的合理性。

关键词：显微组织力学性能 Al−Cu−Li基合金 Sc合金化双辊铸轧

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