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Red light induces salicylic acid accumulation by activating CaHY5 to enhance pepper resistance against Phytophthora capsici 被引量:1
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作者 Youxin Yang Yu Li +8 位作者 Yelan Guang Jinhui Lin Yong Zhou Ting Yu Fei Ding Yanfeng Wang Jinyin Chen Yanhong Zhou Fengfeng Dang 《Horticulture Research》 SCIE CSCD 2023年第11期240-252,共13页
Pepper(Capsicum annuum L.)is frequently challenged by various pathogens,among which Phytophthora capsici is the most devastating to pepper production.Red light signal acts as a positive induction of plant resistance a... Pepper(Capsicum annuum L.)is frequently challenged by various pathogens,among which Phytophthora capsici is the most devastating to pepper production.Red light signal acts as a positive induction of plant resistance against multiple pathogens.However,little is known about how the red light signal affects pepper resistance to P.capsici infection(PCI).Here,we report that red light regulates salicylic acid(SA)accumulation by activating elongated hypocotyl5(CaHY5),a basic leucine zipper(bZIP)transcription factor,thereby decreasing pepper susceptibility to PCI.Exogenous SA treatment reduced pepper susceptibility to PCI,while silencing of CaPHYB(a red light photoreceptor)increased its susceptibility.PCI significantly induced CaHY5 expression,and silencing of CaHY5 reduced SA accumulation,accompanied by decreases in the expression levels of phenylalanine ammonia-lyase 3(CaPAL3),CaPAL7,pathogenesis-related 1(CaPR1),and CaPR1L,which finally resulted in higher susceptibility of pepper to PCI.Moreover,CaHY5 was found to activate the expression of CaPAL3 and CaPAL7,which are essential for SA biosynthesis,by directly binding to their promoters.Further analysis revealed that exogenous SA treatment could restore the resistance of CaHY5-silenced pepper plants to PCI.Collectively,this study reveals a critical mechanism through which red light induces SA accumulation by regulating CaHY5-mediated CaPAL3 and CaPAL7 expression,leading to enhanced resistance to PCI.Moreover,red light-induced CaHY5 regulates pepper resistance to PCI,which may have implications for PCI control in protected vegetable production. 展开更多
关键词 PEPPER resistance light
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Obtaining 2D Soil Resistance Profiles from the Integration of Electrical Resistivity Data and Standard Penetration Test (SPT) and Light Dynamic Penetrometer (DPL) Resistance Tests—Applications in Mass Movements Studies
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作者 Cassiano Antonio Bortolozo Tatiana Sussel Gonçalves Mendes +10 位作者 Mariana Ferreira Benessiuti Motta Silvio Jorge Coelho Simões Tristan Pryer Daniel Metodiev Marcio Roberto Magalhães de Andrade Maiconn Vinicius de Moraes Danielle Silva de Paula Nélio José Bastos Luana Albertani Pampuch Rodolfo Moreda Mendes Marcio Augusto Ernesto de Moraes 《International Journal of Geosciences》 2023年第9期840-854,共15页
In Brazil and various regions globally, the initiation of landslides is frequently associated with rainfall;yet the spatial arrangement of geological structures and stratification considerably influences landslide occ... In Brazil and various regions globally, the initiation of landslides is frequently associated with rainfall;yet the spatial arrangement of geological structures and stratification considerably influences landslide occurrences. The multifaceted nature of these influences makes the surveillance of mass movements a highly intricate task, requiring an understanding of numerous interdependent variables. Recent years have seen an emergence in scholarly research aimed at integrating geophysical and geotechnical methodologies. The conjoint examination of geophysical and geotechnical data offers an enhanced perspective into subsurface structures. Within this work, a methodology is proposed for the synchronous analysis of electrical resistivity geophysical data and geotechnical data, specifically those extracted from the Light Dynamic Penetrometer (DPL) and Standard Penetration Test (SPT). This study involved a linear fitting process to correlate resistivity with N10/SPT N-values from DPL/SPT soundings, culminating in a 2D profile of N10/SPT N-values predicated on electrical profiles. The findings of this research furnish invaluable insights into slope stability by allowing for a two-dimensional representation of penetration resistance properties. Through the synthesis of geophysical and geotechnical data, this project aims to augment the comprehension of subsurface conditions, with potential implications for refining landslide risk evaluations. This endeavor offers insight into the formulation of more effective and precise slope management protocols and disaster prevention strategies. 展开更多
关键词 GEOPHYSICS Geotechnical Data Electrical resistivity Method Standard Penetration Test (SPT) light Dynamic Penetrometer (DPL) Mass Movements
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Theoretical and experimental analysis of the effects of the series resistance on luminous efficacy in GaN-based light emitting diodes
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作者 马莉 沈光地 +3 位作者 刘建朋 高志远 徐晨 王勋 《Chinese Physics B》 SCIE EI CAS CSCD 2014年第11期630-633,共4页
In this paper, a new equivalent circuit model of GaN-based light emitting diodes (LEDs) is established. The impact of the series resistance to luminous efficacy is simulated using the MATLAB software. GaN-based LEDs... In this paper, a new equivalent circuit model of GaN-based light emitting diodes (LEDs) is established. The impact of the series resistance to luminous efficacy is simulated using the MATLAB software. GaN-based LEDs with different n- contact electrode materials (LEDs with Ni/Au and LEDs with Cr/Au) are fabricated. By comparing and analyzing the results of performances, we concluded that both the series resistance and the carrier loss could affect the luminous efficacy severely. LEDs with lower series resistance have higher luminous efficacy and its efficiency droop is alleviated simultaneously. To improve luminous efficacy, the fabrication process should be optimized for lower series resistance. 展开更多
关键词 GaN-based light emitting diodes series resistance luminous efficacy
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Dependence of Performance of Organic Light-emitting Devices on Sheet Resistance of Indium-tin-oxide Anodes 被引量:2
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作者 ZHOU Liang ZHANG Hong-jie YU Jiang-bo MENG Qing-guo PENG Chun-yun LIU Feng-yi DENG Rui-ping PENG Ze-ping LI Zhe-feng 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2006年第4期427-431,共5页
The dependence of the performance of organic light-emitting devices(OLEDs) on the sheet resistance of indiumtin-oxide(ITO) anodes was investigated by measuring the steady state current density brightness voltage c... The dependence of the performance of organic light-emitting devices(OLEDs) on the sheet resistance of indiumtin-oxide(ITO) anodes was investigated by measuring the steady state current density brightness voltage characteristics and the electroluminescent spectra. The device with a higher sheet resistance anode shows a lower current density, a lower brightness level, and a higher operation voltage. The electroluminescence(EL) efficiencies of the devices with the same structure but different ITO anodes show more complicated differences. Furthermore, the shift of the light-emitting zone toward the anode was found when an anode with a higher sheet resistance was used. These performance differences are discussed and attributed to the reduction of hole injection and the increase in voltage drop over ITO anode with the increase in sheet resistance. 展开更多
关键词 Organic light-emitting device(OLED) Indium-tin-oxide(ITO) Sheet resistance Balance of holes and electrons
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A study on light-aging resistance of instrument panel materials and bumper materials on the automobile
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作者 Wang Wentao Liu Qiang +1 位作者 Li Li Li Huilian 《Engineering Sciences》 EI 2014年第3期43-47,共5页
The light-aging test method commonly used in the automotive industry is utilized to carry out light- aging research on automotive instrument panel (IP) materials and bumper materials. On one hand, the impacts of com... The light-aging test method commonly used in the automotive industry is utilized to carry out light- aging research on automotive instrument panel (IP) materials and bumper materials. On one hand, the impacts of common light-aging test methods on aging degree of automotive component materials are reviewed; on the other hand, the light-aging resistances of different component materials are compared. The results show that, for light-aging behavior of IP materials, the aging degree of the third test method is not severer than that of the second method, but it is severer than that of the first method. The light-aging resistance of IP material A is al- most the same as that of IP material B. With reference to light-aging behavior of bumper materials, the aging de- gree of three common test methods indicates that the aging degree of the sixth test method is not severer than that of the fourth method, but it is severer than that of the fifth method. The light-aging resistance of bumper material D is superior to that of bumper material C. 展开更多
关键词 AUTOMOBILE IP MATERIALS BUMPER MATERIALS light-aging resistance color DIFFERENCE GLOSS
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Microstructure and mechanical properties of dissimilar steel plate resistance plug welding joints 被引量:6
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作者 Li Linhe Chen Furong 《China Welding》 EI CAS 2017年第2期43-51,共9页
A new type of hybrid welding method called resistance plug welding (RPW) was firstly adopted to achieve the connecting of dissimilar steel, mainly as for the poor welding characteristics of high strength stee... A new type of hybrid welding method called resistance plug welding (RPW) was firstly adopted to achieve the connecting of dissimilar steel, mainly as for the poor welding characteristics of high strength steel produced by increasing carbon, manganese, silicon, etc. Microstructures and mechanical properties of RPW joint were analyzed by optical microscope,micro-hardness test and shear tensile measurement. Experimental results indicate that the RPW joint has a rounded rectangle nugget ^ and the size is larger than elliptical nugget of resistance spot welding (RSW) jo in t; the hardness value of RPW joint is evenly distributed, accordingly there is no hard brittle phases ; the shear tensile strength o f RPW joint increases by 20% in comparison with RSW joint under the same welding conditions. 展开更多
关键词 light weight dissimilar steel resistance spot welding resistance plug welding
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Hydrothermal Preparation and White-Light-Controlled Resistive Switching Behavior of BaWO_4 Nanospheres 被引量:1
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作者 Bai Sun Yonghong Liu +2 位作者 Wenxi Zhao Jinggao Wu Peng Chen 《Nano-Micro Letters》 SCIE EI CAS 2015年第1期80-85,共6页
In this work, BaWO4 nanospheres were successfully prepared by hydrothermal process. The bipolar resistive switching behavior of Ag/BaWO4/FTO device is observed. Moreover, this resistive switching behavior can be modul... In this work, BaWO4 nanospheres were successfully prepared by hydrothermal process. The bipolar resistive switching behavior of Ag/BaWO4/FTO device is observed. Moreover, this resistive switching behavior can be modulated by white light. The device can maintain superior stability in the dark and under white-light illumination. This study is useful for developing the light-controlled nonvolatile memory devices. 展开更多
关键词 BaWO4 nanospheres resistive switching Hydrothermal preparation White light
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Superhydrophobic Light Alloy Materials with Corrosion-Resistant Surfaces 被引量:1
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作者 Xiaowei XUN Rili ZHU +4 位作者 Jiaojiao DONG Ting PAN Meiling ZHONG Richao ZHANG Dongmian ZANG 《Research and Application of Materials Science》 2020年第1期1-11,共11页
Metals and their alloys are irreplaceable engineered materials showing great importance in our society.Light alloy materials(i.e.,Mg,Al,Ti,and their alloys)have tremendous application potential in the aerospace,automo... Metals and their alloys are irreplaceable engineered materials showing great importance in our society.Light alloy materials(i.e.,Mg,Al,Ti,and their alloys)have tremendous application potential in the aerospace,automotive industries,and biomedical fields for they are lighter and have excellent mechanical properties.The corrosion of light alloys is ubiquitous and greatly restricts their utilization.Inspired by the natural anti-water systems,many new designs and conceptions have recently emerged to create artificial superhydrophobic surfaces with great potential for corrosion resistant of light alloy.This review firstly introduces the concept of superhydrophobicity and strategies of producing superhydrophobic surfaces to inhibit the corrosion of light alloys.In addition,we elaborate the durability of superhydrophobic light alloy materials for commercial and industrial applications,and present their anticorrosion mechanism in the corrosive media. 展开更多
关键词 light alloys SUPERHYDROPHOBICITY corrosion resistance mechanical durability
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Heat-Resistant Properties of a SiO<sub>2</sub>-Coated PET Film Prepared by Irradiating a Polysilazane-Coated Film with Excimer Light
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作者 Tomoji Ohishi Kousei Ichikawa Satoki Isono 《Materials Sciences and Applications》 2020年第1期58-69,共12页
Flexible electronics have been recently paid much attention. A flexible substrate (Organic resin film) is indispensable component for flexible devices. Though PET film is low-cost organic film, low heat-resistance of ... Flexible electronics have been recently paid much attention. A flexible substrate (Organic resin film) is indispensable component for flexible devices. Though PET film is low-cost organic film, low heat-resistance of PET film limits its application as a flexible device substrate. We have developed heat-resistant PET which does not deteriorate even at 190&deg;C heat treatment for one hour. An excimer light was irradiated onto a polysi-lazane (PHPS: perhydropolysilane)-coated film to form a dense silicon-dioxide (SiO2) layer on a PET film, and the heat-resistance property of the formed film was examined. Changes of surface state and cross-sectional structure of the formed film due to heat treatment were investigated by scanning electron microscope (SEM) and transmission electron microscope (TEM). Compared to normal PET, which is deteriorated and whitened by heat treatment of about 110&deg;C - 120&deg;C, the SiO2-coated PET film maintains transparency and does not deteriorate after heat treatment at 180&deg;C - 190&deg;C for one hour. This high heat resistance is due to a dense SiO2 film formed on the surface that prevents surface precipitation and crystallization of low-molecular-weight oligomers (which are the cause of thermal degradation of PET). It is expected that enhancing the heat resistance of PET—which has high versatility and low cost—to about 180&deg;C to 190&deg;C will allow SiO2-film-coated PET to be developed as a film substrate for flexible devices. 展开更多
关键词 POLYSILAZANE Dense Silica Thin FILM Photo-Irradiation EXCIMER light Heat resistance PET FILM Flexible Electronics
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Highly Selective Photodynamic Therapy with a Short Drug-Light Interval Using a Cytotoxic Photosensitizer Porphyrus Envelope for Drug-Resistant Prostate Cancer Cells
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作者 Youngsoon Hong Mizuho Inai +6 位作者 Norihiro Honda Hisanao Hazama Manjusha A. Joshi Hiroyuki Nakamura Tomoyuki Nishikawa Yasufumi Kaneda Kunio Awazu 《International Journal of Clinical Medicine》 2018年第1期8-22,共15页
Background: Photodynamic therapy (PDT) is a less invasive cancer treatment using photochemical reactions induced by light irradiation to a photosensitizer (PS). Highly selective PDT with fast accumulation of the PS in... Background: Photodynamic therapy (PDT) is a less invasive cancer treatment using photochemical reactions induced by light irradiation to a photosensitizer (PS). Highly selective PDT with fast accumulation of the PS in target site might be a promising treatment option for drug-resistant prostate cancer facing high incidence rate of elderly men who have no effective treatment options and require a minimally invasive treatment. Hemagglutinating virus of Japan envelope (HVJ-E) allows selective and fast drug delivery to the drug-resistant prostate cancer cells via rapid cell membrane fusion. PS named porphyrus envelope (PE) has been developed by insertion of lipidated protoporphyrin IX (PpIX lipid) into HVJ-E. In this study, we investigated the optimal conditions for PE preparation and laser irradiation for highly selective PDT using PE with a short drug-light interval. Materials and Methods: Human hormon refractory prostate cancer cell line PC-3 and human normal prostate epithelial cell line PNT2 were cultured. PpIX lipid uptake and cytotoxicity of PDT in the cells incubated with PE for 10 min were evaluated by measuring fluorescence intensity and by using a cell counting reagent 24 h after PDT, respectively. Results: PpIX lipid uptake and cytotoxicity of PDT were increased with PpIX lipid concentration. Cytotoxicity of PDT using PE was more than 9 times as strong as that with PpIX lipid and PpIX induced by 5-aminolevulinic acid. Much stronger cytotoxicity was induced in PC-3 cells than PNT2 cells with the ratio of cell death rate for cancer to normal cells up to 4.64 ± 0.09. Conclusions: Fast PS delivery with HVJ-E allows highly selective PDT with a short drug-light interval. Therefore, PDT using PE has a potential to shorten treatment period and reduce side effects of PDT. 展开更多
关键词 Photodynamic Therapy Hemagglutinating Virus of Japan ENVELOPE DRUG Delivery System SHORT Drug-light INTERVAL DRUG-resistANT Prostate Cancer
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低品位蓝晶石制备锂离子电池窑炉用莫来石轻质隔热材料
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作者 孙华云 《耐火材料》 CAS 北大核心 2024年第2期155-160,共6页
为实现对低品位蓝晶石的综合利用,以低品位蓝晶石、α-Al_(2)O_(3)微粉和黏土为主要原料,在10 MPa下机压成型,分别经1450和1500℃保温3 h热处理,通过燃尽物法制备了莫来石轻质隔热材料。研究了黏土加入量(加入质量分数分别为5%、10%、15... 为实现对低品位蓝晶石的综合利用,以低品位蓝晶石、α-Al_(2)O_(3)微粉和黏土为主要原料,在10 MPa下机压成型,分别经1450和1500℃保温3 h热处理,通过燃尽物法制备了莫来石轻质隔热材料。研究了黏土加入量(加入质量分数分别为5%、10%、15%、20%)和热处理温度(1450、1500℃)对试样体积密度、显气孔率、常温耐压强度、热导率以及抗锂离子电池正极材料侵蚀性能和显微结构的影响。结果表明:黏土的引入促进了试样的致密化和莫来石化反应,提高了试样体积密度、热导率和强度,添加20%(w)黏土的试样经1450℃烧后物理性能最佳,其体积密度为0.88 g·cm^(-3),常温耐压强度为21.0 MPa,热导率为0.25 W·(m·K)^(-1);当热处理温度为1450℃,黏土加入量为10%(w)时,试样具有较好的抗锂离子电池正极材料侵蚀性能。 展开更多
关键词 低品位蓝晶石 莫来石 轻质隔热材料 抗侵蚀性
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轻钢龙骨复合墙板研究进展
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作者 苗纪奎 孙飞 +1 位作者 单后壮 宋娜 《新型建筑材料》 2024年第9期61-68,共8页
装配式钢结构建筑具有抗震性能好、自重轻、施工速度快等优点,但因与其配套的围护外墙板较少,制约了装配式钢结构的发展。近年来结构轻便、保温性能好、抗震性能优良的轻钢龙骨复合墙板被逐渐应用到装配式钢结构建筑当中。对现有轻钢龙... 装配式钢结构建筑具有抗震性能好、自重轻、施工速度快等优点,但因与其配套的围护外墙板较少,制约了装配式钢结构的发展。近年来结构轻便、保温性能好、抗震性能优良的轻钢龙骨复合墙板被逐渐应用到装配式钢结构建筑当中。对现有轻钢龙骨复合墙板进行了分类,总结了各类墙板的特点,并介绍了国内外针对墙板的抗弯性能、抗剪性能、抗震性能以及热工性能等方面的研究现状。在此基础上,分析了轻钢龙骨复合墙板存在的问题,提出了一种热工与防火性能好、自重轻、连接安全可靠、管线易于分离且可工业化生产的新型轻钢龙骨复合墙板。 展开更多
关键词 轻钢龙骨 墙板 抗弯性能 抗剪性能 抗震性能 热工性能
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纳米微晶纤维素复合膜的制备及性能分析
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作者 柴翠元 《韶关学院学报》 2024年第3期6-11,共6页
以具有可持续性和环保特点的棉纤维为原料制备纳米微晶纤维素(NCC),再通过硫酸水解法简单高效地制得NCC悬浮液,将该悬浮液与壳聚糖混合,制备出NCC复合膜.利用万能试验机测试NCC复合膜的力学拉伸性能,同时用拟杯子法测试NCC复合膜的透湿... 以具有可持续性和环保特点的棉纤维为原料制备纳米微晶纤维素(NCC),再通过硫酸水解法简单高效地制得NCC悬浮液,将该悬浮液与壳聚糖混合,制备出NCC复合膜.利用万能试验机测试NCC复合膜的力学拉伸性能,同时用拟杯子法测试NCC复合膜的透湿性、用覆盖油脂的过氧化值测试NCC复合膜的阻氧性、用分光光度计测试NCC复合膜的透光性、用金黄色葡萄球菌和大肠杆菌测试NCC复合膜的抗菌性,最后用细胞培养试验评估复合膜对人体细胞的毒性.结果表明,NCC用量在45%质量分数时,制备的NCC复合膜拉伸强度最大、力学性能最高、断裂界面更粗糙;NCC复合膜水蒸气透过率保持在2.8×10^(-11) g·(m·s·Pa)^(-1)以上;NCC复合膜氧气阻隔性的过氧化值在2.0以上;经过与NCC复合膜32 min的接触,金黄色葡萄球菌和大肠杆菌接近完全被杀灭;24 h人体细胞存活率在70%以上.综上,所制备的NCC复合膜性能优良,值得开发. 展开更多
关键词 纳米微晶 纤维素 复合膜 透湿性 阻氧性 透光性 抗菌性
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采用双区截光幕测速装置标定靶距的方法
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作者 李敬 孙忠辉 +1 位作者 倪晋平 田会 《光子学报》 EI CAS CSCD 北大核心 2024年第2期140-149,共10页
针对短靶距测速光幕靶的靶距无法直接测量的问题,提出一种采用双区截光幕测速装置标定靶距的方法。在测得弹道上两点速度后,依据弹道方程推导了飞行弹丸在两点间任意时刻的瞬时速度计算式;依据弹丸穿过标定用测速装置和被标定光幕靶的... 针对短靶距测速光幕靶的靶距无法直接测量的问题,提出一种采用双区截光幕测速装置标定靶距的方法。在测得弹道上两点速度后,依据弹道方程推导了飞行弹丸在两点间任意时刻的瞬时速度计算式;依据弹丸穿过标定用测速装置和被标定光幕靶的时间序列,给出了靶距标定公式。在弹丸飞行速度一定的情况下,分析标定用光幕靶的靶距和布放间距对标定误差的影响,并进行了实弹射击试验。试验结果表明,标定用光幕靶的靶距、布放间距及弹丸飞行速度在一定条件下,标定相对误差为0.8‰,所提方法能够用来标定各种原理的使用级区截测速用传感器的靶距。 展开更多
关键词 速度测量 光幕靶 标定 阻力参数 误差传递
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红蓝光质复配对银杏幼苗光合特性及黄酮醇含量的影响
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作者 王峥 王改萍 +2 位作者 赵群 翟金庭 余鹏飞 《西北植物学报》 CAS CSCD 北大核心 2024年第11期1673-1681,共9页
【目的】探究不同红蓝配比光质对银杏生长、光合与黄酮醇积累及抗氧化能力的影响,筛选适宜银杏生长与黄酮积累的光质,为调控提高银杏叶药用价值提供理论依据。【方法】以2年生银杏实生苗为试材,设红蓝比例为1∶1(1R1B)、1∶3(1R3B)、1∶... 【目的】探究不同红蓝配比光质对银杏生长、光合与黄酮醇积累及抗氧化能力的影响,筛选适宜银杏生长与黄酮积累的光质,为调控提高银杏叶药用价值提供理论依据。【方法】以2年生银杏实生苗为试材,设红蓝比例为1∶1(1R1B)、1∶3(1R3B)、1∶5(1R5B)和白光(W,对照)4种光质处理,分析处理20 d后银杏生长、光合生理、黄酮醇含量及抗氧化能力。【结果】与白光相比,不同比例红蓝光均降低了银杏叶生物量,不利于株高地径的生长,却有利于提高叶长、叶宽、叶面积及光合气体交换参数。1R5B处理可提高叶片总叶绿素含量;1R1B处理促进了叶片总生物量积累;1R3B处理下叶片叶绿素荧光参数、抗氧化能力以及类胡萝卜素和总黄酮醇含量最大。【结论】适宜比例红蓝光配比光质对银杏生长及光合特性产生明显影响,并显著提高叶黄酮醇含量与抗氧化能力,且1R3B配比光质最有利于银杏黄酮类物质积累。 展开更多
关键词 银杏 光质 光合特性 黄酮醇 抗氧化能力
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改性轻烧氧化镁细粉的抗水化性能
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作者 薛天雨 黄仲 +1 位作者 黄忍 张海军 《耐火材料》 CAS 北大核心 2024年第1期30-34,共5页
为解决MgO的易水化问题,以乙二醇和聚异丁烯顺丁烯酸酐共聚物(ISOBAM-104)为改性剂,经混合、研磨、热处理对轻烧MgO细粉进行了改性处理,研究了ISOBAM-104的加入量(分别加入MgO细粉质量的0、1%、3%、5%、7%、9%)和热处理温度(200、250、... 为解决MgO的易水化问题,以乙二醇和聚异丁烯顺丁烯酸酐共聚物(ISOBAM-104)为改性剂,经混合、研磨、热处理对轻烧MgO细粉进行了改性处理,研究了ISOBAM-104的加入量(分别加入MgO细粉质量的0、1%、3%、5%、7%、9%)和热处理温度(200、250、300℃保温1 h)对改性后轻烧MgO的物相组成、显微结构及抗水化性的影响。结果表明:当ISOBAM-104的加入量为MgO细粉质量的7%时,经250℃保温1 h热处理后改性轻烧MgO的水化质量增加率最低,为2.2%。ISOBAM-104/乙二醇改性轻烧MgO细粉抗水化性能提高的主要原因是其表面生成了醇镁化合物及疏水性亚酰胺基团。 展开更多
关键词 轻烧MgO 热处理诱导法 抗水化性
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桉木表面构建层状双氢氧化物仿紫光檀颜色
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作者 穆雨晴 何林韩 +3 位作者 王浏浏 罗玉芬 陈瑶 高建民 《北京林业大学学报》 CAS CSCD 北大核心 2024年第5期126-135,共10页
【目的】针对人工林速生桉木材色较浅、表面色调单一的问题,以层状双金属氢氧化物(LDHs)对其进行材色调控,仿制名贵木材紫光檀的黑棕色效果。【方法】将与木材高度亲和的钴基金属有机框架(Co-MOF)作为模板和前驱体,利用MnCl_(2)在木材... 【目的】针对人工林速生桉木材色较浅、表面色调单一的问题,以层状双金属氢氧化物(LDHs)对其进行材色调控,仿制名贵木材紫光檀的黑棕色效果。【方法】将与木材高度亲和的钴基金属有机框架(Co-MOF)作为模板和前驱体,利用MnCl_(2)在木材表面发生水解反应,在桉木单板表面制备钴锰层状双金属氢氧化物(CoMn-LDH);探究桉木单板分别在0.016、0.032、0.064 mol/L MnCl_(2)溶液和20、40、60、80℃条件下表面颜色的变化规律;并通过扫描电镜(SEM)、X射线衍射(XRD)、X射线光电子能谱(XPS)和红外光谱(FT-IR)分析,探究LDHs与桉木单板表面的结合机理;通过接触角和耐光老化测试评估改色木材的耐水性和耐光老化性。【结果】(1)在40℃下,利用0.032 mol/L MnCl_(2)溶液制得的钴锰双氢氧化物涂层桉木单板实现了紫光檀颜色效果,两者的色度值和紫外光谱均相近。(2)MnCl_(2)水解诱导Co-MOF和木材的OH−交换形成金属氢氧化物,生成CoMn-LDH;SEM显示CoMn-LDH具有微纳米复合结构,XRD和XPS分析表明钴和锰分别以Co^(2+)和Mn^(2+)的形式存在,CoMn-LDH为典型的钴锰双氢氧化物;其红外光谱呈金属–羟基振动模式。(3)调色木材的接触角由36.2°增大至49.5°;光照120 h后色差在3~6范围内,属于中质量分辨率下可见色差;表明制备的钴锰双氢氧化物涂层桉木单板表面疏水能力和耐光老化性能均得到提升。【结论】本研究所用调色处理条件温和,能有效改善桉木颜色,提高产品装饰效果和附加值,促进人工林木材的高效利用。 展开更多
关键词 桉木 钴锰层状双氢氧化物 紫光檀颜色 调色机理 耐光老化性 木材染色
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微生物活化钾长石对玉米抗弱光低温逆境的研究初报
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作者 沈彦汐 吴瑶瑶 +3 位作者 廖宗文 乔凯 陈先玉 蔡燕飞 《肥料与健康》 CAS 2024年第4期49-54,共6页
解钾菌活化钾长石的肥效不仅与微生物的活化效果有关,还与微生物的抗光温逆境功能有关。在3个恒温光照培养箱分别设置了弱光、全光和弱光低温条件下的玉米苗栽培试验,比较化肥(氯化钾)、微生物活化钾长石和化学活化钾长石在不同光温条... 解钾菌活化钾长石的肥效不仅与微生物的活化效果有关,还与微生物的抗光温逆境功能有关。在3个恒温光照培养箱分别设置了弱光、全光和弱光低温条件下的玉米苗栽培试验,比较化肥(氯化钾)、微生物活化钾长石和化学活化钾长石在不同光温条件下的肥效。结果表明:微生物活化钾长石在全光和弱光条件下的肥效均优于化肥的,揭示了微生物不仅能活化矿质营养,还具有抗光温逆境的功能;在弱光条件下,微生物活化钾长石处理的玉米鲜质量和干质量较优,表明微生物分泌物提供的有机碳营养可补充弱光下光合产物的亏缺,其优势得以凸显;在全光条件下,化学活化钾长石处理的玉米鲜质量和干质量较高,表明全光条件下的光合产物较弱光条件下的有大幅增加,使碳亏缺大为缓解,其肥效得以更好地发挥;就抗光温逆境而言,化肥处理仍然不具有微生物活化的优势。 展开更多
关键词 玉米 钾长石 弱光 低温 微生物 抗逆
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光信号和昼夜节律调控植物感知冷胁迫的研究进展
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作者 李文萃 彭羽佳 刘勇波 《生物技术通报》 CAS CSCD 北大核心 2024年第8期1-12,共12页
温度和光是调节植物生长发育的重要环境因子,植物感知温度变化并通过改变基因表达模式等响应低温环境,这些响应受到光信号和昼夜节律等因素的影响。然而,光信号诱导昼夜节律调控植物响应冷胁迫的分子调控网络尚不清楚。本文聚焦光信号... 温度和光是调节植物生长发育的重要环境因子,植物感知温度变化并通过改变基因表达模式等响应低温环境,这些响应受到光信号和昼夜节律等因素的影响。然而,光信号诱导昼夜节律调控植物响应冷胁迫的分子调控网络尚不清楚。本文聚焦光信号和昼夜节律在植物感知冷胁迫中的作用。光信号参与冷胁迫主要通过光敏色素诱导CBF基因途径激活冷基因的表达,这主要有两种途径,一是光敏色素受体通过直接调控CBF和COR基因表达而调节植株抗冷性;二是光依赖性信号转导的正调控因子HY5激活冷驯化COR基因。昼夜节律参与冷胁迫主要是通过昼夜节律的组分CCA1/LHY和RVE4/RVE8介导DREB1下游基因在冷胁迫下的表达。明确植物中光信号和昼夜节律在冷信号感知及传导途径中的作用,不仅有助于更好地理解植物抗冷的机制和功能,还有助于植物生长与温度胁迫反应之间的权衡,为提升植物应对昼夜温差变化提供理论基础。 展开更多
关键词 冷感知 抗冷基因 光信号 昼夜节律
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受阻胺光稳定剂对葡萄膜抗农药性的影响 被引量:1
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作者 苏明 秦立洁 +1 位作者 刘丙伟 赵伟婷 《塑料》 CAS CSCD 北大核心 2024年第2期35-40,共6页
葡萄由于易感染白粉病、霜霉病等病害,常使用石硫合剂进行喷洒。石硫合剂在使用时呈酸性,可使葡萄膜中的碱性受阻胺光稳定剂(HALS)钝化、失去活性,导致棚膜提前破损。加入抗农药型HALS进行葡萄膜制备,并在西昌和昆明建水进行农田追踪试... 葡萄由于易感染白粉病、霜霉病等病害,常使用石硫合剂进行喷洒。石硫合剂在使用时呈酸性,可使葡萄膜中的碱性受阻胺光稳定剂(HALS)钝化、失去活性,导致棚膜提前破损。加入抗农药型HALS进行葡萄膜制备,并在西昌和昆明建水进行农田追踪试验。综合分析S、Cl残留量和样品力学保留率,结果表明,西昌扣棚1.5年最高残留量S为1112×10^(-6),Cl为109×10^(-6)。N2R和NOR类HALS比传统N-H结构HALS更具有抗酸性能;NOR类HALS与N2R相比较好;此外,复配HALS的效果较好,1#西昌扣棚1.5年后拉伸强度保留率纵横向分别为83.8%和70.2%,断裂伸长保留率纵横向分别为108.3%和96.6%;水滑石有吸酸优势,性价比更高,8#西昌扣棚1.5年后拉伸强度保留率纵横向分别为63.3%和68.3%,断裂伸长保留率纵横向分别为84.9%和101.3%。 展开更多
关键词 石硫合剂 葡萄膜 抗农药型受阻胺光稳定剂 农田试验 耐候性
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