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Small particles,big effects:How nanoparticles can enhance plant growth in favorable and harsh conditions

Journal of Integrative Plant Biology 2024年第7期66卷 1274-1294页

作者： Jie wang Honghong Wu yichao wang Wuwei Ye Xiangpei Kong Zujun Yin Zhengzhou Research Base State Key Laboratory of Cotton Bio‐breeding and Integrated UtilizationSchool of Agricultural SciencesZhengzhou UniversityZhengzhou 450001China State Key Laboratory of Cotton Bio‐breeding and Integrated Utilization Institute of Cotton ResearchChinese Academy of Agricultural SciencesAnyang 455000China National Key Laboratory of Crop Genetic Improvement Huazhong Agricultural UniversityWuhan 430070China School of Engineering Design and Built EnvironmentWestern Sydney UniversityPenrith NSW 2751Australia Western Agricultural Research Center Chinese Academy of Agricultural SciencesChangji 831100China The Key Laboratory of Plant Development and Environmental Adaptation Biology Ministry of EducationCollege of Life SciencesShandong UniversityQingdao 266237China

By 2050,the global population is projected to reach 9 billion,underscoring the imperative for innovative solutions to increase grain yield and enhance food *** has emerged as a powerful tool,providing unique solutions to this ***(NPs)can improve plant growth and nutrition under normal conditions through their high surface-to-volume ratio and unique physical and chemical ***,they can be used to monitor crop health status and augment plant resilience against abiotic stresses(such as salinity,drought,heavy metals,and extreme temperatures)that endanger global *** of NPs can enhance stress tolerance mechanisms in plants,minimizing potential yield losses and underscoring the potential of NPs to raise crop yield and *** review highlights the need for a comprehensive exploration of the environmental implications and safety of nanomaterials and provides valuable guidelines for researchers,policymakers,and agricultural *** thoughtful stewardship,nanotechnology holds immense promise in shaping environmentally sustainable agriculture amid escalating environmental challenges.

关键词： abiotic stress agricultural defense system nano-particles nanotechnology oxidative stress reactive oxygen species toxicity

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Mechanical properties of steel mesh in anchor-mesh support for rocky tunnels

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Journal of Mountain Science 2024年第10期21卷 3487-3502页

作者： SUN Keguo JIA Jinglong XU Weiping ZHANG Yu wang Jinjin wang yichao LIU Yongkui Key Laboratory of Transportation Tunnel Engineering Ministry of EducationSchool of Civil EngineeringSouthwest Jiaotong UniversityChengdu 610031China State Key Laboratory of Intelligent Geotechnics and Tunnelling Chengdu 610031China Chengdu Rail Transit Group Co. Ltd.Chengdu 610036China China Railway 14th Bureau Group 2nd Engineering Corporation Limited China Railway Construction Corporation LimitedTaian 271000China

Underground geotechnical engineering encounters persistent challenges in ensuring the stability and safety of surrounding rock structures, particularly within rocky tunnels. Rock reinforcement techniques, including the use of steel mesh, are critical to achieving this goal. However, there exists a knowledge gap regarding the comprehensive understanding of the mechanical behavior and failure mechanisms exhibited by steel mesh under diverse loading conditions. This study thoroughly explored the steel mesh's performance throughout the entire loading-failure process, innovating with detailed analysis and modeling techniques. By integrating advanced numerical modeling with laboratory experiments, the study examines the influence of varying reinforcement levels and geometric parameters on the steel mesh strength and deformation characteristics. Sensitivity analysis, employing gray correlation theory, identifies the key factors affecting the mesh performance, while a BP (Backpropagation) neural network model predicts maximum vertical deformation with high accuracy. The findings underscore the critical role of steel diameter and mesh spacing in optimizing peak load capacity, displacement, and energy absorption, offering practical guidelines for design improvements. The use of a Bayesian Regularization (BR) algorithm further enhances the predictive accuracy compared to traditional methods. This research provides new insights into optimizing steel mesh design for underground applications, offering an innovative approach to enhancing structural safety in geotechnical projects.

关键词： Tunnel Steel mesh BP neural network Anchor-mesh support Rock reinforcement technique

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Acoustic emission characteristics of damage evolution of multi-scale fiber reinforced rubberized concrete under uniaxial compression and tension after being subjected to high temperatures

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Frontiers of Structural and Civil Engineering 2024年第8期18卷 1237-1266页

作者： Shaoqi ZHANG Yao ZHANG Qianru LEI Yumeng YANG yichao wang Fei XU Zhiguo YAN Hehua ZHU Laboratory of Fire Safety School of Safety Engineering and Emergency ManagementShijiazhuang Tiedao UniversityShijiazhuang 050043China Structural Health Monitoring and Control Key Laboratory of Hebei Province Shijiazhuang Tiedao UniversityShijiazhuang 050043China Department of Geotechnical Engineering Tongji UniversityShanghai 200092China

Recently developed multi-scale fiber(i.e.,CaCO3 whisker,polyvinyl alcohol(PVA)fiber,and steel fiber)reinforced rubberized concrete exhibits excellent mechanical properties and spalling resistance at high *** of macro properties such as strength and Young’s modulus cannot reveal and characterize damage mechanisms,particularly those relating to the multi-scale fiber strengthening *** this study,acoustic emission(AE)technology is applied to investigate the impact of multi-scale fiber on the damage evolution of rubberized concrete exposed to high temperatures,under the uniaxial compression and tension loading *** mechanical properties,AE event location,peak frequency,b-value,the ratio of rise time to amplitude(RA),average frequency(AF)values,and AE energy of specimens are *** results show that the number of events observed using AE gradually increases as the loading *** crumb rubber and fibers inhibit the generation and development of the *** is concluded that both the peak frequency and b-value reflect the extension process of *** the cracks develop from the micro scale to the macro scale,the peak frequency tends to be distributed in a lower frequency range,and the b-value decreases *** the peak stress point,the AE energy increases rapidly and the b-value *** specimens without multi-scale fibers exhibit brittle failure,while the specimens with fibers exhibit ductile *** addition,adding multi-scale fibers and crumb rubber increases the peak frequency in the medium and high frequency ranges,indicating a positive effect on inhibiting crack *** being subjected to high temperatures,the maximum and minimum b-values decrease,reflecting an increase in the number of initial cracks due to thermal ***,the RA and AF values are used to classify tensile and shear *** specimens fracture with more shear cracks under compression,and there are more tensile

关键词： multi-scale fibers acoustic emission fracture damage evolution rubberized concrete

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Design and test of a wheel-belt type cotton stalk puller

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International Journal of Agricultural and Biological Engineering 2024年第2期17卷 102-108页

作者： Jialin Cai Jiaxi Zhang Zebin Gao Xiaoxuan wang Gang Guo Yasenjiang Baikeli Xuepeng Tang yichao wang College of Mechanical and Electrical Engineering Xinjiang Agricultural UniversityUrumqi 830052China Key Laboratory of Xinjiang Intelligent Agricultural Equipment Urumqi 830052China

During the harvesting process,rigid materials are prone to causing damage to the cotton stalks,which will increase the risk of stalk breakage.A cotton stalk pulling component that blends stiff and flexible materials was devised to lower the breaking *** cotton stalk pulling component was made up of rollers and flexible belts that pull the stalks using clamping force and the forward speed of the *** influence of various factors in the equipment on the harvesting effect of cotton stalks were analyzed through response surface experiments,and a multiple quadratic regression response surface model with missing pulling rate and breakage rate as response values was *** significant of influencing factors on the breaking rate of cotton stalks are in a descending order as:the angle of cotton stalk pulling,tractor’s forward speed,and the clamping speed of the cotton stalk *** working parameters of the wheel-belt type cotton stalk pulling machine have been optimized using the response surface combination experimental method,and the optimal parameter combination was obtained as:tractor forward speed of 4.5 km/h,cotton stalk pulling angle of 60°,and clamping speed of the cotton stalk pulling component of 349 r/*** results of validation experiments showed that the missing pulling rate of cotton stalks was 5.06%and the breakage rate was 13.12%,indicating a good harvesting effect of the cotton *** model was reasonable and the performance parameters could meet the relevant inspection *** results can provide a reference for further research on the technology of flexible cotton stalk pulling.

关键词： cotton stalk puller wheeled belt flexible cotton stalks pulling verification testing

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Near infrared emissions from both high efficient quantum cutting (173%) and nearly-pure-color upconversion in NaY(WO_(4))_(2):Er^(3+)/Yb^(3+) with thermal management capability for silicon-based solar cells

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Light(Science & Applications) 2024年第1期13卷 113-126页

作者： Duan Gao Baojiu Chen Xuezhu Sha Yuhang Zhang Xin Chen Li wang Xizhen Zhang Jinsu Zhang Yongze Cao yichao wang Lei Li Xiangping Li Sai Xu Hongquan Yu Lihong Cheng School of Science Dalian Maritime UniversityDalian 116026 LiaoningChina

Raising photoelectric conversion efficiency and enhancing heat management are two critical concerns for siliconbased solar *** this work,efficient Yb^(3+) infrared emissions from both quantum cutting and upconversion were demonstrated by adjusting Er^(3+) and Yb^(3+) concentrations,and thermo-manage-applicable temperature sensing based on the luminescence intensity ratio of two super-low thermal quenching levels was discovered in an Er^(3+)/Yb^(3+) codoped tungstate *** quantum cutting mechanism was clearly decrypted as a two-step energy transfer process from Er^(3+) to Yb^(3+).The two-step energy transfer efficiencies,the radiative and nonradiative transition rates of all interested 4 f levels of Er^(3+) in NaY(WO_(4))_(2) were confirmed in the framework of Föster-Dexter theory,Judd-Ofelt theory,and energy gap law,and based on these obtained efficiencies and rates the quantum cutting efficiency was furthermore determined to be as high as 173%in NaY(WO_(4))_(2):5 mol%Er^(3+)/50 mol%Yb^(3+) *** and nearly pure infrared upconversion emission of Yb3+under 1550 nm excitation was achieved in Er^(3+)/Yb^(3+)co-doped NaY(WO_(4))_(2) by adjusting Yb^(3+) doping *** Yb^(3+) induced infrared upconversion emission enhancement was attributed to the efficient energy transfer ^(4)I_(11/2)(Er^(3+))+^(2)F_(7/2)(Yb^(3+))→^(4)I_(15/2)(Er^(3+))+^(2)F_(5/2)(Yb^(3+))and large nonradiative relaxation rate of ^(4)I_(9/2).Analysis on the temperature sensing indicated that the NaY(WO_(4))_(2):Er^(3+)/Yb^(3+)serves well the solar cells as thermos-managing ***,it was confirmed that the fluorescence thermal quenching of ^(2)H_(11/2)/^(4)S_(3/2) was caused by the nonradiative relaxation of ^(4)S_(3/2).All the obtained results suggest that NaY(WO_(4))_(2):Er^(3+)/Yb^(3+) is an excellent material for silicon-based solar cells to improve photoelectric conversion efficiency and thermal management.

关键词： quantum thermal relaxation

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基于多源数据融合的可持续发展目标监测与评估研究进展

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地球科学进展 2024年第2期39卷 181-192页

作者：王一超生态环境部华南环境科学研究所/国家环境保护城市生态环境模拟与保护重点实验室广东广州510535

2015年联合国《2030年可持续发展议程》提出了17个可持续发展目标(SDGs)。国内外学者正持续开展SDGs监测评估研究,数据缺失和指标监测能力不足等问题被认为是当前制约SDGs常态化监测评估的重要因素。为了应对这些问题,需要加强指标的监... 详细信息

2015年联合国《2030年可持续发展议程》提出了17个可持续发展目标(SDGs)。国内外学者正持续开展SDGs监测评估研究,数据缺失和指标监测能力不足等问题被认为是当前制约SDGs常态化监测评估的重要因素。为了应对这些问题,需要加强指标的监测能力和数据获取能力。综合应用多源数据开展SDGs监测评估研究可有效弥补上述不足,并逐渐成为了国内外学术界的研究热点。相关研究工作可以归纳为3类:第一类研究侧重于讨论基于多源数据的SDGs监测评估基础理论和方法体系;第二类研究主要开展基于多源数据的SDGs监测评估案例研究;第三类研究和实践的重点是加强多源数据相关的基础能力建设。通过对比基于多源数据的研究案例和常规研究案例中所使用的指标类型差异,探讨多源数据的应用前景。结果表明,多源数据的应用可以加强对自然生态系统的评价、识别需要重点关注的地区、分析人与自然的交互作用、强化空间分析能力,可以有效弥补数据缺失等不足,并且提高指标数据的及时性和时空分辨率,可以极大地丰富SDGs的评价指标体系。未来可以从4个方面加强多源数据在SDGs监测评估中的应用:拓展多源数据在SDGs中的应用范围、促进多学科交叉和综合研究、在国家可持续发展议程创新示范区中试点多源数据的应用以及强化多源数据相关基础能力建设。

关键词：可持续发展目标多源数据监测评估指标体系

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食管原发性透明细胞鳞状细胞癌伴Paget样播散1例

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中华病理学杂志 2024年第10期53卷 1045-1048页

作者：王一超周杭城中国科学技术大学附属第一医院(安徽省立医院)临床病理中心、中国科学技术大学智慧病理学研究所合肥230036

食管原发性透明细胞鳞状细胞癌较为罕见,伴有Paget样播散易误诊为食管Paget病。本文报道1例81岁女性食管原发性透明细胞鳞状细胞癌伴Paget样播散,胸腹部CT显示食管中下段交界处管壁局限性明显增厚。镜下见肿瘤细胞胞质透明,可见核仁、... 详细信息

食管原发性透明细胞鳞状细胞癌较为罕见,伴有Paget样播散易误诊为食管Paget病。本文报道1例81岁女性食管原发性透明细胞鳞状细胞癌伴Paget样播散,胸腹部CT显示食管中下段交界处管壁局限性明显增厚。镜下见肿瘤细胞胞质透明,可见核仁、核分裂象及奇异核型,黏膜鳞状上皮见胞质透明的单个、小巢状异型细胞,呈Paget样沿周围鳞状上皮播散。免疫组织化学染色及特殊染色结果:细胞角蛋白(CK)5/6、p40、p63、广谱细胞角蛋白(CKpan)、INI1、BRG1阳性,p53突变型表达,CK7、CK8、MUC1局灶阳性,CK20、癌胚抗原、GCDFP15、HNF1β、MUC2、MUC5AC、MUC6、HMB45、S‑100蛋白、GATA3、PAX8、嗜铬粒素A、突触素、波形蛋白阴性。过碘酸雪夫染色显示颗粒状阳性,淀粉酶消化的过碘酸雪夫染色显示颗粒状物消失,提示细胞内含糖原,是细胞质透明的原因。本例肿瘤侵袭性强,伴有神经侵犯及脉管癌栓,淋巴结见癌转移,患者术后11个月死亡。

关键词：透明细胞食管中下段 GATA3 特殊染色异型细胞鳞状细胞癌细胞胞质 p63

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柔性刷辊式葡萄藤清土机设计与试验

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农业机械学报 2024年第2期55卷 138-148,219页

作者：李金明张佳喜王茂博杨兴元王毅超新疆农业大学机电工程学院乌鲁木齐830052 新疆智能农业装备重点实验室乌鲁木齐830052 乌鲁木齐优尼克生物科技有限公司乌鲁木齐830052 新疆农业大学食品科学与药学学院乌鲁木齐830052

为解决新疆地区现有葡萄藤清土机械伤藤率高、彩条布上方大量覆土影响葡萄藤清土上架和彩条布回收的问题,采用柔性刷辊设计了一种刷辊式葡萄藤清土机。该机关键部件为清土装置,作业时通过清土刷的旋转运动和横向伸缩机构的往复运动将彩... 详细信息

为解决新疆地区现有葡萄藤清土机械伤藤率高、彩条布上方大量覆土影响葡萄藤清土上架和彩条布回收的问题,采用柔性刷辊设计了一种刷辊式葡萄藤清土机。该机关键部件为清土装置,作业时通过清土刷的旋转运动和横向伸缩机构的往复运动将彩条布上方的覆土清除。首先进行清土刷结构设计和材料选择,然后对清土刷工作过程进行运动学理论分析,得到影响清土机作业性能的主要参数。通过单因素试验确定清土刷转速、横向伸缩机构往复速度、清土刷回转直径的合理取值范围,以清土刷转速、横向伸缩机构往复速度、清土刷回转直径为试验因素,以清土率和伤藤率为评价指标,开展三因素三水平正交试验。试验结果表明,各试验影响因素对清土率和伤藤率的影响显著性大小顺序为清土刷转速、横向伸缩机构往复速度、清土刷回转直径。较优参数组合为:清土刷转速250 r/min、横向伸缩机构往复速度0.14 m/s和清土刷回转直径600 mm,在此参数组合下进行3次验证试验取平均值,清土率为90.98%,伤藤率为3.27%,与优化值相对误差均小于5%,证明样机设计合理。

关键词：刷辊式葡萄藤清土机正交试验

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面向行星表面元素测量的小型化伽马谱仪原理样机设计

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核电子学与探测技术 2024年第1期44卷 6-17页

作者：黄磊王轶超封常青王宇王婷刘树彬中国科学技术大学核探测与核电子学国家重点实验室合肥230026 中国科学技术大学近代物理系合肥230026 深空探测实验室合肥230022

对行星表面物质受宇宙射线激发或天然衰变而产生的伽马射线进行探测,是一种测量行星表面主要元素成分及其空间分布的可靠技术手段,已被多个行星探测任务采用。提出了将CZT探测器与SiPM读出闪烁晶体相结合的行星元素伽马谱仪方案,该方案... 详细信息

对行星表面物质受宇宙射线激发或天然衰变而产生的伽马射线进行探测,是一种测量行星表面主要元素成分及其空间分布的可靠技术手段,已被多个行星探测任务采用。提出了将CZT探测器与SiPM读出闪烁晶体相结合的行星元素伽马谱仪方案,该方案兼具低能段的高能量分辨率和高能段的高探测效率,同时可以减小来自非探测方向伽马背景的影响,且具有较小的体积、重量和功耗。为进行初步的技术路线验证,设计了一个将CZT阵列(单个灵敏尺寸1 cm×1 cm×0.5 cm)与BGO探测器(晶体的主体尺寸8.4 cm×8.4 cm×4 cm)相结合的小型化伽马谱仪原理样机,并开展了物理模拟。完成了前端探测器模块、数据处理模块和FPGA控制逻辑的设计实现,以及原理样机的组装。使用放射源、上海光源激光伽马光束线和中子激发伽马对谱仪进行了测试,CZT探测器对^(137)Cs@662 keV伽马射线的能量分辨率(FWHM)为2.1%,可以较好地分辨低能伽马射线,BGO晶体能够较好地探测和分辨高能伽马射线。该方案为未来小型化行星伽马谱仪的工程设计提供了参考。

关键词：伽马谱仪行星元素测量 CZT探测器读出电子学

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成都万佛寺造像碑中的佛寺园林图像研究

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绵阳师范学院学报 2024年第9期43卷 123-131,146页

作者：张博王一潮天水师范学院美术与艺术设计学院甘肃天水741001

佛寺园林是兴起于东晋、南朝时期的中国园林样式。成都市万佛寺的“元嘉二年造像碑”“梁二菩萨造像碑”和“须弥山造像碑”背面雕刻有独特的园林图像,图像较为客观地表现了东晋、南朝时期佛寺园林的艺术风貌,同时这三幅图像也是现已发... 详细信息

佛寺园林是兴起于东晋、南朝时期的中国园林样式。成都市万佛寺的“元嘉二年造像碑”“梁二菩萨造像碑”和“须弥山造像碑”背面雕刻有独特的园林图像,图像较为客观地表现了东晋、南朝时期佛寺园林的艺术风貌,同时这三幅图像也是现已发现创作时间最早的“净土图式经变”题材的佛教美术作品。通过考证,万佛寺造像碑上的“净土图式经变”是参照南朝佛寺园林,应用全景式的构图,采用南朝“台榭”画的方法创造而成。图像运用了三段式分层的布局方法,通过将各种物象归纳为“梯形”图式并加以组合的方式,表现出南朝佛寺园林宏大的场面和深远的意境。万佛寺造像碑参照世俗社会中的佛寺园林作为“净土图式经变”绘画原型的创作方法,影响了敦煌唐代“净土变”题材壁画的创作。

关键词：佛寺园林 “台榭”画净土图式经变全景式构图 “梯形”图式

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