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Effects of Sodium Chloride Stress on Growth of Sweet Potato Plantlets in vitro and Ion Content 被引量:13
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作者 高叶 赵术珍 +2 位作者 陈敏 宋晓征 王宝山 《Agricultural Science & Technology》 CAS 2008年第5期27-30,共4页
[Objective] This study aimed to investigate the salt-tolerance mechanism of sweet potato.[Method]Two sweet potato varieties of Xu 25-2(salt-tolerant cultivar)and Triumph 100(salt-sensitive cultivar)were treated by sod... [Objective] This study aimed to investigate the salt-tolerance mechanism of sweet potato.[Method]Two sweet potato varieties of Xu 25-2(salt-tolerant cultivar)and Triumph 100(salt-sensitive cultivar)were treated by sodium chloride with the concentration of 0 mmol/L and 100 mmol/L.After 20 days,Na+ content and Na+/K+ ratio in the roots,shoots and leave were determined by the flame photometer,while dry weight and fresh weight of roots,shoots and leave in different varieties were also studied.[Result]The growth of two sweet potato varieties was inhibited under salt stress,so the plant became shorter,leaf and root became fewer,dry weight of roots and leave decreased,but seedlings of Xu 25-2 were inhibited slightly.Furthermore,Na+ content and Na+/K+ ratio in roots,shoots and leaves of two sweet potato varieties increased.Na+ content of salt-tolerant Xu 25-2 was low in roots,shoots and leaves,while Na+ content of salt-sensitive Triumph 100 was high in shoots and leave of seedlings,but the change range of Xu 25-2 was less than that of Triumph 100.[Conclusion]The lower Na+ content and Na+/K+ ratio in leaves under salt stress were the most important characteristics for salt-tolerance of sweet potato varieties. 展开更多
关键词 SALT STRESS Sweet potato Test-tube PLANTLET GROWTH ion content SALT tolerance
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Effect of salinity on seed germination, growth and ion content in dimorphic seeds of Salicornia europaea L. (Chenopodiaceae) 被引量:8
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作者 Nikolai Orlovsky Ulbasyn Japakova +1 位作者 Huifan Zhang Sergei Volis 《Plant Diversity》 SCIE CAS CSCD 北大核心 2016年第4期183-189,共7页
The halophyte Salicornia europaea L. is a widely distributed salt-tolerant plant species that produces numerous dimorphic seeds. We studied germination and recovery in dimorphic seeds of Central Asian S. europaea unde... The halophyte Salicornia europaea L. is a widely distributed salt-tolerant plant species that produces numerous dimorphic seeds. We studied germination and recovery in dimorphic seeds of Central Asian S. europaea under various salinity conditions. We also tested the effects of various salts on Na+ and K+ accumulation during plant development from germination to anthesis under greenhouse conditions. We found good germination (close to control) of large seeds under NaCl between 0.5 and 2%, Na2SO4 and 2NaCl + KCl + CaCl between 0.5 and 3%, and 2Na2SO4 + K2SO4 -- MgSO4 between 0.5 and 5%. For the small seeds, we found stimulating effects of chloride salts (both pure and mixed) under 0.5-1% concentrations, and sulfate salts under 0.5-3%. Both types of seeds showed high germination recovery potential. Salt tolerance limits of the two seed types during germination and at the later stages of development were very similar (4-5%). During plant growth the optimal concentrations of mixed chloride and sulfate salts ranged from 0.5 to 2%. The mechanisms of salt tolerance in the two seed types of S. europaea appear to differ, but complement each other, improving overall adaptation of this species to high salinity. 展开更多
关键词 Dimorphic seeds Germination Salinity Recovery ion content
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Chloride Ion Critical Content in Reinforced Concrete 被引量:1
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作者 李岩 Laura STIRNEMANN 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2007年第4期737-740,共4页
Chloride ion critical content was studied under soaking and cycle of dry and wet conditions, with three electrochemical nondestructive measuring techniques, i e, half-cell potential, A C impedance, and time potential.... Chloride ion critical content was studied under soaking and cycle of dry and wet conditions, with three electrochemical nondestructive measuring techniques, i e, half-cell potential, A C impedance, and time potential. The experimental results show that chloride ion critical content is primarily determined by the water cement ratio, while for the same concrete mixture the chloride ion critical content in soaking conditions is larger than that in a cycle of dry and wet conditions. 展开更多
关键词 chloride ion cycle of dry and wet critical content A C impedance
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《水泥基渗透结晶型防水材料》国标修订解读
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作者 杨斌 张永明 +3 位作者 戈兵 朱志远 陈斌 王莹 《中国建筑防水》 2026年第1期36-43,共8页
系统介绍了GB/T 18445—2025《水泥基渗透结晶型防水材料》国家标准的修订背景、主要技术内容及实施要点;重点阐述了标准在分类、技术指标、试验方法及耐久性评价等方面的优化调整,特别是对防水剂氯离子含量、收缩率比等关键参数的加严... 系统介绍了GB/T 18445—2025《水泥基渗透结晶型防水材料》国家标准的修订背景、主要技术内容及实施要点;重点阐述了标准在分类、技术指标、试验方法及耐久性评价等方面的优化调整,特别是对防水剂氯离子含量、收缩率比等关键参数的加严,以及自修复能力试验方法的引入等。 展开更多
关键词 水泥基渗透结晶型防水材料 国家标准 抗渗性能 自修复能力 氯离子含量 试验方法 刚性防水
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Effects of Salinity and Potassium Application on Antioxidant Enzyme Activities and Physiological Parameters in Pearl Millet 被引量:7
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作者 Mostafa Heidari Parisa Jamshidi 《Agricultural Sciences in China》 CAS CSCD 2011年第2期228-237,共10页
A plot culture experiment was conducted in a greenhouse at University of Zabol,Iran,to study the effects of different salinity levels and potassium supply on pearl millet.The experiment was laid out in a completely ra... A plot culture experiment was conducted in a greenhouse at University of Zabol,Iran,to study the effects of different salinity levels and potassium supply on pearl millet.The experiment was laid out in a completely randomized factorial design with three replicates.Potassium sulfate was used as the potassium source.The rates of potassium treatments were 0,100,and 200 kg ha-1.Pearl millet was subjected to different salinity levels(0,4,8,and 12 ds m-1) through addition of NaCl to irrigation water.Results showed that the increase in the salt concentration from control to 12 ds m-1 decreased grain yield(38.7%) of millet plants.In this study,we found a negative relationship between potassium and proline accumulation at vegetative(r2=-0.75**) and reproductive stage(r2=-0.66**) in millet plants.Salt stress remarkably elevated the activities of CAT and GPX antioxidant enzymes at vegetative and reproductive stages.Furthermore,potassium application had significant effect on grain yield and increased it about 10.6% at the highest salinity treatment(12 ds m-1).Though,potassium treatment increased antioxidant activity in millet plants,it had no significant effect on proline content in leaves.Salinity treatment decreased potassium uptake but application potassium increased potassium content in leaves at two stages. 展开更多
关键词 antioxidants enzymes ion content pearl millet POTASSIUM PROLINE SALINITY
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矿物吸附剂对水泥窑协同处置熟料固化重金属性能的影响 被引量:1
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作者 朱绘美 马雨晴 +1 位作者 孙晓 李辉 《水泥》 2026年第1期10-14,共5页
针对水泥窑协同处置过程中半挥发性重金属Pb易挥发、固化率低的问题,本研究以高岭土为基础材料,采用等质量替代法分别引入硅灰、氢氧化铝和碳酸钙,制备了高硅、高铝和高钙三类改性矿物吸附剂。系统考察了其在0~1 450℃温度范围内的物相... 针对水泥窑协同处置过程中半挥发性重金属Pb易挥发、固化率低的问题,本研究以高岭土为基础材料,采用等质量替代法分别引入硅灰、氢氧化铝和碳酸钙,制备了高硅、高铝和高钙三类改性矿物吸附剂。系统考察了其在0~1 450℃温度范围内的物相演变规律及其对Pb固化行为的影响。通过熟料煅烧实验、游离氧化钙含量测定、重金属总量分析、化学形态提取及浸出毒性测试等方法,综合评价了各类吸附剂对熟料易烧性、Pb固化率及元素分布以及环境安全性的作用效果。结果表明,高硅改性吸附剂在1%掺量下,可使熟料中Pb的含量显著提升至基准组的3.63倍,并能有效改善Pb在熟料中的分布均匀性。KS中Pb主要以残渣态存在(占比达95%),表现出良好的化学稳定性;所制备水泥浆体中Pb的浸出浓度远低于国家标准限值,环境风险较低。本研究可为水泥窑协同处置过程中高效、耐高温矿物吸附剂的筛选与实际应用提供理论依据与技术参考。 展开更多
关键词 矿物吸附剂 水泥窑协同处置 熟料 重金属固化
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Deterioration Mechanisms of Sulfate Attack on Concrete under Alternate Action 被引量:8
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作者 高润东 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2010年第2期355-359,共5页
By micro- and macro-observations, the deterioration mechanisms of concrete under alternate action between repeated sub-high temperature/cooling by water and sodium sulfate solution attack (TW-SA) were studied; meanw... By micro- and macro-observations, the deterioration mechanisms of concrete under alternate action between repeated sub-high temperature/cooling by water and sodium sulfate solution attack (TW-SA) were studied; meanwhile, the single sodium sulfate solution attack (SA) was also done as comparison. Micro-observations included the analysis of attack products by thermal analysis method and the determination of sulfate-ion content from surface to interior by chemical titrating method (modified barium sulfate gravimetric method). Macro-observations mainly included the mechanical behaviors such as compressive strength, splitting strength. The experimental results indicate, in both cases, the main attack product is ettringite, only in the first layer of case SA some gypsum is checked; in case SA, the sulfate ions mainly concentrate in the surface layer, so the attack is relatively mild; but in case TW-SA, the repeated sub-high temperature/cooling by water promotes the sulfate ions diffusing inwards, which leads to obvious strength degradation. 展开更多
关键词 CONCRETE SULFATE repeated sub-high temperature/cooling by water attack product sulfate-ion content strength
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Effects of parasitic plant Cistanche deserticola on chlorophyll a fluorescence and nutrient accumulation of host plant Haloxylon ammodendron in the Taklimakan Desert 被引量:1
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作者 Li LI XinWen XU +2 位作者 YongQiang SUN WeiHAN PengFei TU 《Journal of Arid Land》 SCIE 2012年第3期342-348,共7页
The parasitic plant Cistanche deserticola attaches to Haloxylon ammodendron, a perennial shrub with high tolerance to salinity and drought. However, little was known about the parasite-host relation between the two sp... The parasitic plant Cistanche deserticola attaches to Haloxylon ammodendron, a perennial shrub with high tolerance to salinity and drought. However, little was known about the parasite-host relation between the two species. Effects of the parasite on chlorophyll a fluorescence and nutrient accumulation in the host plant (H. am- modendron) were investigated in the Taklimakan Desert. Some photosynthetic parameters of both host and non-host H. ammodendron plants were measured by in vivo chlorophyll a fluorescence technology in the field. The assimilating branches of host and non-host plants were collected and nutrient and inorganic ion contents were analyzed. The results from field experiments showed that the infection of C. deserticola reduced the non-photochemical quenching of the variable chlorophyll fluorescence (NPQ) and the potential maximum quantum yield for primary photochemistry (Fv/Fm) of the host. Compared with non-host plants, the host H. ammodendron had low nutrient, low inorganic ion contents (Na~ and K~) and low K~/Na~ ratios in the assimilating branches. It suggested that C. deserticola infection reduced the nutrient acquisition and caused damage to the photoprotection through thermal dissipation of the energy of the photosystem II in the host, resulting in a decrease in the tolerance to salinity and high radiation. It was concluded that the attachment of the parasite plant (C. deserticola) had negative effects on the growth of its host. 展开更多
关键词 parasite-host relation nutrient acquisition inorganic ion content non-photochemical quenching the Taklimakan Desert
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水泥窑协同处置替代燃料中氯离子含量不同前处理方式的比较分析
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作者 马长鹏 方磊 许跃兵 《水泥》 2026年第1期15-17,共3页
水泥窑协同处置替代燃料检测氯离子的前处理方式较多,本文主要对马弗炉灼烧法、艾士卡混合剂溶样法以及氧弹燃烧法三种检测方法进行研究,并对其优缺点进行对比分析。结果表明,采用氧弹燃烧法和艾士卡混合试剂溶样法处理不同类型的替代... 水泥窑协同处置替代燃料检测氯离子的前处理方式较多,本文主要对马弗炉灼烧法、艾士卡混合剂溶样法以及氧弹燃烧法三种检测方法进行研究,并对其优缺点进行对比分析。结果表明,采用氧弹燃烧法和艾士卡混合试剂溶样法处理不同类型的替代燃料样品时,检测结果均在合理误差范围之内,满足测试要求。其中氧弹燃烧法操作更加简便,在检测热值的同时可有效利用其燃烧后残留的检测液进行分析,处理时样品不受限制;艾士卡混合试剂溶样法检测精度和准确度较高,能够保证测试结果相对偏差在5%以内,但操作过程烦琐,对检测人员和检测过程要求极高。 展开更多
关键词 水泥窑协同处置 替代燃料 氯离子含量 氧弹燃烧 检测方法
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动力锂电池用硫酸镍中镍主含量与痕量杂质铜联合分析的方法改进研究
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作者 顾运琼 李冬玉 +3 位作者 蒋秋霞 莫江敏 甘春芳 秦臻 《当代化工研究》 2026年第1期185-187,共3页
针对动力锂电池用硫酸镍的质量控制需求,建立了一种EDTA络合滴定与火焰原子吸收光谱(AAS)联用的分析方法,用于同时准确测定硫酸镍中主量元素镍与痕量杂质铜的含量。该方法依据HG/T 5918~5919—2021电池级硫酸镍的技术要求进行设计:一份... 针对动力锂电池用硫酸镍的质量控制需求,建立了一种EDTA络合滴定与火焰原子吸收光谱(AAS)联用的分析方法,用于同时准确测定硫酸镍中主量元素镍与痕量杂质铜的含量。该方法依据HG/T 5918~5919—2021电池级硫酸镍的技术要求进行设计:一份样品在pH=8~10的氨性缓冲体系中,以紫脲酸铵为指示剂,采用EDTA标准溶液滴定,测定质量分数大于20%的镍主含量;另一份样品经稀释后,于324.7 nm波长下采用AAS法测定质量分数低于0.0005%的铜杂质。方法学验证结果显示,镍含量测定的相对标准偏差(RSD,n=4)为0.02%~0.05%,铜含量测定RSD(n=3)为0,铜的加标回收率达101.71%。该方法操作简便、结果准确、成本低廉,与传统方法相比具有明显优势,完全满足电池级硫酸镍产品中镍(≥22.0%)与铜(≤0.0005%)的质控标准,适用于企业质量检测与高校实验教学,具有较好的推广价值。 展开更多
关键词 镍离子/铜离子含量 原子吸收光谱法 络合滴定法 方法改进
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2D titanium carbide(MXene) electrodes with lower-F surface for high performance lithium-ion batteries 被引量:13
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作者 Ming Lu Haojie Li +9 位作者 Wenjuan Han Junnan Chen Wen Shi Jiaheng Wang Xiang-Min Meng Jingang Qi Haibo Li Bingsen Zhang Wei Zhang Weitao Zheng 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2019年第4期148-153,共6页
MXene has shown distinctive advantages as anode materials of lithium-ion batteries. However, local surface chemistry, which was confirmed that can block ion transfer and limit redox reaction, has a significant effect ... MXene has shown distinctive advantages as anode materials of lithium-ion batteries. However, local surface chemistry, which was confirmed that can block ion transfer and limit redox reaction, has a significant effect on electrochemical performance. Herein, annealing MXene under hydrogen was employed for removing-F and turning-OH to-O terminations. We demonstrate that it improves the kinetics of Li-ion transport between the electrolyte and electrode. As a result, a lower interfacial charge transfer impedance was obtained. The electrochemical measurement exhibited that a nearly 2-fold increase of specific capacity was achieved for the annealed MXene. 展开更多
关键词 Ti3C2 MXene LI-ion Hydrogen -F content
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母岩类型与石粉含量对机制砂混凝土力学性能及耐久性的影响探讨
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作者 贾俊斌 《广东建材》 2026年第2期30-33,共4页
为优化提升机制砂混凝土力学性能,通过制备不同类型机制砂混凝土,利用室内试验分析了石粉含量与母岩类型对机制砂混凝土抗压强度及氯离子渗透系数的影响。结果表明:流纹质晶屑凝灰岩机制砂混凝土相较于其他石灰岩、花岗岩及辉绿岩母岩... 为优化提升机制砂混凝土力学性能,通过制备不同类型机制砂混凝土,利用室内试验分析了石粉含量与母岩类型对机制砂混凝土抗压强度及氯离子渗透系数的影响。结果表明:流纹质晶屑凝灰岩机制砂混凝土相较于其他石灰岩、花岗岩及辉绿岩母岩类型的机制砂混凝土具有良好的力学性能及耐久性能;随流纹质晶屑凝灰岩粉含量的不断增加,混凝土的抗压强度先增长后降低,混凝土的氯离子渗透系数先降低后增加,在流纹质晶屑凝灰岩石粉含量为3%的条件下,混凝土的氯离子渗透系数为3.6×10^(-12)m^(2)/s。因此,最佳流纹质晶屑凝灰岩石粉掺量为3%。 展开更多
关键词 机制砂混凝土 母岩类型 石粉含量 抗压强度 抗氯离子渗透系数
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Morphological and biochemical responses of Oryza sativa L.(cultivar MR219) to ion beam irradiation 被引量:5
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作者 Anna Pick Kiong LING Ying Chian UNG +3 位作者 Sobri HUSSEIN Abdul Rahim HARUN Atsushi TANAKA Hase YOSHIHIRO 《Journal of Zhejiang University-Science B(Biomedicine & Biotechnology)》 SCIE CAS CSCD 2013年第12期1132-1143,共12页
Objective: Heavy ion beam, which has emerged as a new mutagen in the mutation breeding of crops and ornamental plants, is expected to result in the induction of novel mutations. This study investigates the morphologic... Objective: Heavy ion beam, which has emerged as a new mutagen in the mutation breeding of crops and ornamental plants, is expected to result in the induction of novel mutations. This study investigates the morphological and biochemical responses of Oryza sativa toward different doses of carbon ion beam irradiation. Methods: In this study, the dry seeds of O. sativa were irradiated at 0, 20, 40, 60, 80, 100, and 120 Gy, followed by in-vitro germination under controlled conditions. Morphological and biochemical studies were conducted to investigate the morphological and physiological responses of O. sativa towards ion beam irradiation. Results: The study demonstrated that low doses(10 Gy) of ion beam have a stimulating effect on the height, root length, and fresh weight of the plantlets but not on the number of leaves. Meanwhile, doses higher than 10 Gy caused reductions in all the morphological parameters studied as compared to the control samples. The highest total soluble protein content [(2.11±0.47) mg/g FW] was observed in plantlets irradiated at 20 Gy. All irradiated plantlets were found to have 0.85% to 58.32% higher specific activity of peroxidase as compared to the control samples. The present study also revealed that low doses of ion beam(10 and 20 Gy) had negligible effect on the total chlorophyll content of O. sativa plantlets while 40 Gy had a stimulating effect on the chlorophyll content. Plantlets irradiated between 40 to 120 Gy were shown to be 0.38% to 9.98% higher in total soluble nitrogen content which, however, was not significantly different from the control samples. Conclusions: Carbon ion beam irradiation administered at low to moderate doses of 10 to 40 Gy may induce O. sativa mutants with superior characteristics. 展开更多
关键词 In vitro mutagenesis ion beam irradiation Total chlorophyll content Total soluble protein content Mutation breeding
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Influence of Si Content on Properties of Ti1-xSixN Coatings 被引量:3
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作者 WAN Qiang LIU Nian +2 位作者 YANG Bing LIU Huidong CHEN Yanming 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2019年第4期774-780,共7页
To investigate the evolution of microstructure and wear behavior of TiSiN coatings with the variation of Si in targets and lays the foundation for its controllable mass production, Ti1-xSixN composite coatings were de... To investigate the evolution of microstructure and wear behavior of TiSiN coatings with the variation of Si in targets and lays the foundation for its controllable mass production, Ti1-xSixN composite coatings were deposited onto Si(100) and cemented carbide substrates using TiSi targets with different Si content by cathodic arc ion plating. The influences of Si on the microstructure and mechanical properties were studied. Nano-amorphous composite structure appeared in the Ti1-xSixN coatings when Si content in TiSi target was higher than 5 at%. However, further increase of Si content in TiSi target exhibited a negligible effect on the microstructure of Ti1-xSixN coatings. Hardness and deformation resistance were correlated to the content of Si in TiSi targets. Maximum hardness was obtained as the Si content in target increased up to 20 at%. Friction coefficient and wear rate significantly decreased with addition of Si in TiN coating, and then dually increased with the increase of Si content in targets. 展开更多
关键词 cathodic ARC ion PLATING Ti(1-x)SixN coating silicon content NANOCOMPOSITE mechanical properties WEAR resistance
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Construction and Application of a PVC Membrane Enoxacin Ion-selective Electrode Based on a Needle-shaped Inner Reference Electrode
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作者 HUANG Chao-lun LI Rui-fen XIU Rong 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2003年第4期409-412,共4页
A PVC membrane enoxacin ion-selective electrode based on a needle-shaped inner reference electrode was prepared. A Ag/AgCl wire was used as the substrate of this electrode. It was previously coated with a thin sheet o... A PVC membrane enoxacin ion-selective electrode based on a needle-shaped inner reference electrode was prepared. A Ag/AgCl wire was used as the substrate of this electrode. It was previously coated with a thin sheet of urea-formaldehyde resin containing Cl - ions to form a needle-shaped inner reference electrode, then the inner reference electrode was coated with a thin sheet of a PVC membrane containing an enoxacin tetraphenylborate ion-pair complex. The influences of various ion-pair complexes, concentrations of the active components in the membrane and the plasticizers on the performance of the electrode were studied by orthogonal design. The linear response range of the electrode was 7.9×10 -5 -1.0×10 -2 mol/L. The detection limit was 2.0×10 -5 mol/L. The slope was 30.4 mV/decade(25 ℃). The electrode can be used for the potentiometric determination of enoxacin tablets directly. The average recovery was 100.4%, and the RSD was 0.9%. The results agreed with those determined by the method in Chinese Pharmacopoeia. 展开更多
关键词 Enoxacin PVC membrane-coated-wire electrode ion-selective electrode content determination
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带裂缝大掺量粉煤灰砂浆氯离子扩散行为研究 被引量:1
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作者 刘扬 毛晟哲 鲁乃唯 《中外公路》 2025年第4期25-32,共8页
为了探究带裂缝大掺量粉煤灰水泥砂浆中氯离子的传输特性,该文采用人工预制裂缝的方式,制备了不同粉煤灰掺量(FA)和不同裂缝宽度的水泥砂浆试件。通过自然浸泡30 d、60 d后,测定试件裂缝内氯离子含量。结果表明:裂缝加快了氯离子在砂浆... 为了探究带裂缝大掺量粉煤灰水泥砂浆中氯离子的传输特性,该文采用人工预制裂缝的方式,制备了不同粉煤灰掺量(FA)和不同裂缝宽度的水泥砂浆试件。通过自然浸泡30 d、60 d后,测定试件裂缝内氯离子含量。结果表明:裂缝加快了氯离子在砂浆中的传输速度,其中0.05 mm与0.10 mm裂缝宽度对氯离子扩散系数的增大程度相近,而0.20 mm裂缝宽度对扩散系数的增大程度显著;30 d浸泡后,FA50在侵蚀深度大于10 mm范围内的氯离子含量随深度增加而显著降低;浸泡60 d后,所有试件的氯离子含量均随深度增加显著降低;当粉煤灰掺量不大于40%时,砂浆的抗氯离子性能随着掺量的增加而改善,但当掺50%粉煤灰时,砂浆的抗氯离子性能急剧下降;裂缝宽度与氯离子扩散系数呈线性关系,而粉煤灰掺量与氯离子扩散系数可用三次函数描述,并建立了考虑粉煤灰掺量和裂缝宽度的扩散系数模型,通过对比试验值与拟合值验证了模型有效性。 展开更多
关键词 裂缝宽度 大掺量粉煤灰 水泥砂浆 氯离子含量 氯离子扩散模型
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以学生为中心,三草酸合铁(Ⅲ)酸钾的制备和铁离子含量测定的教学探索
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作者 刘晓莉 张颖 +2 位作者 杨春 丛继坤 李志强 《广州化工》 2025年第17期188-190,195,共4页
无机化学实验是培养大一学生自主学习、实践技能、创新精神的关键环节,教学中遵循“以学生为中心”的教学理念,以“三草酸合铁(Ⅲ)酸钾的制备和铁离子含量的测定”为例,开展综合性实验的探索与实践。产品制备环节有助于提高学生理论联... 无机化学实验是培养大一学生自主学习、实践技能、创新精神的关键环节,教学中遵循“以学生为中心”的教学理念,以“三草酸合铁(Ⅲ)酸钾的制备和铁离子含量的测定”为例,开展综合性实验的探索与实践。产品制备环节有助于提高学生理论联系实际、动手操作能力和探索精神,铁离子含量的测定旨在锻炼学生数据分析能力和测试仪器的规范使用,感光性质的验证增加了课堂的趣味性。 展开更多
关键词 以学生为中心 无机化学实验 三草酸合铁(Ⅲ)酸钾 铁离子含量
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Effect of rich R-TiO2 on the rate and cycle properties of Li4Ti5O12 as anode for lithium ion batteries 被引量:3
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作者 Delai Qian Yijie Gu +5 位作者 Shuainan Guo Hongquan Liu Yunbo Chen Juan Wang Guoxuan Ma Chuan Wu 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2019年第5期182-188,共7页
Li4Ti5012 (LTO) with rich R-TiO2 (17.06, 23.69, and 34.42 wt%), namely, R-TiO2@Li4Ti5O12 composites, were synthesized using the hydrothermal method and tetrabutyl titanate (TBT) as the precursor. Rietveld refinement o... Li4Ti5012 (LTO) with rich R-TiO2 (17.06, 23.69, and 34.42 wt%), namely, R-TiO2@Li4Ti5O12 composites, were synthesized using the hydrothermal method and tetrabutyl titanate (TBT) as the precursor. Rietveld refinement of X-ray diffraction (XRD) results show that the proportion of Li occupying 16d sites is extraordinary low and the lattice constants of LTO and R-TiO2 change with the ritanium dioxide content. EIS measurements showed that with in creasing R-TiO2 content, both its charge transfer impedance (Rct) and lithium ion diffusion coefficient (DLi) decreased. The changes of Rct and DLi caused by the increase of titanium dioxide content have synergic-antagonistic effects on the rate and cycle properties of Li4Ti5012. The rate performance is positively related to DLi, while the cycle property is negatively correlated with Rct, indicati ng that the rate performs nee is mainly related to DLi, while Rct more significantly affects the cycle performance. LTO-RT-17.06% exhibited excellent rate properties, especially under a high current density (5.0 C, 132.5 mAh/g) and LTO-RT-34.42% showed superior long-term cycle performance (0.012% capacity loss per cycle) compared to that of LTO-RT-17.06% and LTO-RT-23.69%. 展开更多
关键词 LI4TI5O12 R-TiO2 content RATE and CYCLE properties Charge transfer impedance LI-ion diffusion coefficient
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盐胁迫下外源水杨酸对甘蓝幼苗生理特性的影响 被引量:1
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作者 李晶菲 李梦娇 +6 位作者 庞青青 战志鹏 刘杨 郭明慧 李大伟 黄炜 许忠民 《蔬菜》 2025年第3期30-38,共9页
为探究干旱、半干旱地区甘蓝抗盐栽培措施,以甘蓝品种‘秦甘50’为试材,采用水培方法,设置叶面喷施蒸馏水(CK)、叶面喷施100μmol/L水杨酸(SA)、人工模拟150 mmol/L NaCl盐胁迫和150 mmol/L NaCl胁迫下喷施100μmol/L水杨酸(SA+NaCl)4... 为探究干旱、半干旱地区甘蓝抗盐栽培措施,以甘蓝品种‘秦甘50’为试材,采用水培方法,设置叶面喷施蒸馏水(CK)、叶面喷施100μmol/L水杨酸(SA)、人工模拟150 mmol/L NaCl盐胁迫和150 mmol/L NaCl胁迫下喷施100μmol/L水杨酸(SA+NaCl)4组处理,分析处理后幼苗的植株形态、生物量、根系活力、叶绿素含量、矿质元素吸收量、抗氧化酶活性、活性氧积累量和叶片脂膜过氧化等指标,研究水杨酸(SA)对盐胁迫下甘蓝幼苗生理特性的影响。结果表明:在盐胁迫下,喷施100μmol/L SA的甘蓝幼苗株高、茎粗、地上部鲜/干质量、地下部鲜/干质量、根系活力、叶绿素含量分别较NaCl组极显著提高108.02%、74.75%、73.27%、81.82%、138.71%、200.00%、564.68%、43.16%,叶片细胞Na^(+)含量较NaCl组极显著降低了17.74%,K^(+)含量极显著提高41.36%,Na^(+)/K^(+)比值极显著下降41.96%,维持了甘蓝植株体内的离子平衡;组织化学染色结果表明,与CK相比盐胁迫造成了严重的叶片损伤和活性氧(ROS)积累,导致叶片丙二醛(MDA)含量、过氧化氢(H_(2)O_(2))含量和超氧阴离子(O_(2)^(-))含量增高,而喷施100μmol/L SA后,甘蓝幼苗中的过氧化氢酶(CAT)、过氧化物酶(POD)和超氧化物歧化酶(SOD)活性分别较NaCl组极显著提高了36.67%、74.15%和25.73%,MDA含量、H_(2)O_(2)含量、O_(2)^(-)含量分别极显著降低13.48%、24.84%、6.01%,抗氧化酶活性的显著提高减少了盐胁迫下的活性氧累积,维持了甘蓝幼苗细胞内氧化还原稳态,从而提升了甘蓝幼苗的抗氧化能力。SA组与CK相比各指标均无显著变化。由此得出,外源喷施100μmol/L SA对甘蓝幼苗在盐胁迫下的生长具有积极的调控作用。 展开更多
关键词 盐胁迫 水杨酸 甘蓝 生理特性 组织化学染色 离子含量 抗氧化酶活性
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丛枝菌根真菌调控盐碱胁迫下棉花生长及离子平衡的研究 被引量:2
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作者 彭梓程 杜洪力 +2 位作者 王铭 张凤华 杨海昌 《中国农业科技导报(中英文)》 北大核心 2025年第2期33-41,共9页
为探究丛枝菌根真菌(arbuscular mycorrhizal fungi,AMF)对棉花苗期逆境离子吸收和运转的影响,采用盆栽试验,以棉花‘新陆早45号’为材料,接种摩西斗管囊霉,以不接种AMF为对照,待棉花生长至3叶期进行不同水平(0、50、100、150、200 mmol... 为探究丛枝菌根真菌(arbuscular mycorrhizal fungi,AMF)对棉花苗期逆境离子吸收和运转的影响,采用盆栽试验,以棉花‘新陆早45号’为材料,接种摩西斗管囊霉,以不接种AMF为对照,待棉花生长至3叶期进行不同水平(0、50、100、150、200 mmol·L^(−1))盐碱胁迫,分析不同处理下棉花幼苗生长及叶、茎、根离子含量的变化。结果表明,棉花根系侵染率随盐碱胁迫程度的增加而逐渐降低,菌根依赖性随盐碱胁迫程度的增加而增加。随着盐碱胁迫程度的增加,棉花幼苗生物量逐渐降低,而接种AMF可显著促进棉花生长发育。在各盐碱胁迫处理下,接种AMF显著提高了棉花幼苗生物量;显著降低棉花幼苗各器官的Na^(+)含量及Na^(+)/K^(+)、Na^(+)/Ca^(2+)、Na^(+)/Mg^(2+),显著提高棉花幼苗各器官的K^(+)、Ca^(2+)、Mg^(2+)含量;降低了Na^(+)由地下向地上的运输,同时增加K^(+)、Ca^(2+)、Mg^(2+)由地下向地上的运输。综上,盐碱胁迫可抑制K^(+)、Ca^(2+)、Mg^(2+)由地下向地上部的运输,接种AMF能够抑制棉花根系对Na^(+)的吸收及向上运输,促进根系对K^(+)、Ca^(2+)、Mg^(2+)的吸收及向上运输,从而降低Na^(+)/K^(+)、Na^(+)/Ca^(2+)、Na^(+)/Mg^(2+),缓解Na^(+)对棉花植株的伤害,促进棉花幼苗的生长发育。 展开更多
关键词 盐碱含量 离子运输比 侵染 棉花
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