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Subsoil tillage enhances wheat productivity,soil organic carbon and available nutrient status in dryland fields
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作者 qiuyan yan Linjia Wu +6 位作者 Fei Dong Shuangdui yan Feng Li Yaqin Jia Jiancheng Zhang Ruifu Zhang Xiao Huang 《Journal of Integrative Agriculture》 SCIE CSCD 2024年第1期251-266,共16页
Tillage practices during the fallow period benefit water storage and yield in dryland wheat crops.However,there is currently no clarity on the responses of soil organic carbon(SOC),total nitrogen(TN),and available nut... Tillage practices during the fallow period benefit water storage and yield in dryland wheat crops.However,there is currently no clarity on the responses of soil organic carbon(SOC),total nitrogen(TN),and available nutrients to tillage practices within the growing season.This study evaluated the effects of three tillage practices(NT,no tillage;SS,subsoil tillage;DT,deep tillage)over five years on soil physicochemical properties.Soil samples at harvest stage from the fifth year were analyzed to determine the soil aggregate and aggregate-associated C and N fractions.The results indicated that SS and DT improved grain yield,straw biomass and straw carbon return of wheat compared with NT.In contrast to DT and NT,SS favored SOC and TN concentrations and stocks by increasing the soil organic carbon sequestration rate(SOCSR)and soil nitrogen sequestration rate(TNSR)in the 0-40 cm layer.Higher SOC levels under SS and NT were associated with greater aggregate-associated C fractions,while TN was positively associated with soluble organic nitrogen(SON).Compared with DT,the NT and SS treatments improved soil available nutrients in the 0-20 cm layer.These findings suggest that SS is an excellent practice for increasing soil carbon,nitrogen and nutrient availability in dryland wheat fields in North China. 展开更多
关键词 TILLAGE dryland wheat fields soil aggregate size soil nutrients soil carbon and nitrogen fractions
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学生在二语写作课堂同伴反馈活动中的投入情况:一个面向中国中学英语学习者的多案例研究
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作者 闫秋燕 唐辰 《Chinese Journal of Applied Linguistics》 2023年第1期120-139,152,共21页
同伴反馈及学生投入研究在过去几十年引发广泛探讨,然而学者们对于同伴反馈活动中学生投入研究的关注相对不足,尤其缺乏对低年级英语学习者如何参与课堂同伴反馈活动的探索。本研究基于多元数据,包括半结构化访谈、刺激性回忆、写作初... 同伴反馈及学生投入研究在过去几十年引发广泛探讨,然而学者们对于同伴反馈活动中学生投入研究的关注相对不足,尤其缺乏对低年级英语学习者如何参与课堂同伴反馈活动的探索。本研究基于多元数据,包括半结构化访谈、刺激性回忆、写作初稿、修改稿和终稿以及同伴讨论录音,探讨了中学英语学习者作为反馈提供者和接收者,如何在行为、认知、情感三个维度参与二语写作课堂中的同伴反馈活动,并一步探索影响投入的因素。研究结果表明:1)学习者在提供和接收反馈的双向投入中都体现了三个维度动态复杂的交互特性;2)学习者在扮演反馈提供者和接收者两种不同身份时,反馈投入存在差异;学习者们可能在作为反馈给予者时表现出深度投入而作为反馈接收者时却漫不经心,反之亦然;3)不同学习者在接收和给予同伴反馈时的投入呈现出不同的特点,这是由英语水平、自我效能感、性格、教师引导等因素引起的。本研究通过挖掘学习者反馈投入的多维特质,可丰富同伴反馈投入的三维理论框架,并为教育实践者们就提高写作课堂中学习者同伴反馈投入提供可行性建议。 展开更多
关键词 学生投入 同伴反馈 反馈投入 二语写作
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Electrostatic assembly functionalization of poly(γ-glutamic acid)for biomedical antibacterial applications 被引量:1
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作者 Xiaodan Wang Hengchong Shi +5 位作者 Haoyu Tang Huan Yu qiuyan yan Huawei yang Xu Zhang Shifang Luan 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2020年第24期14-25,共12页
Poly(γ-glutamic acid)(γ-PGA)has been found widespread applications in biomedical field because of its excellent water solubility,biocompatibility,and bioactivity.Herein,a water-insoluble γ-PGA antibacterial compoun... Poly(γ-glutamic acid)(γ-PGA)has been found widespread applications in biomedical field because of its excellent water solubility,biocompatibility,and bioactivity.Herein,a water-insoluble γ-PGA antibacterial compound is facilely fabricated via one-pot electrostatic assembly of γ-PGA with cationic ethyl lauroyl arginate(ELA).The functionalized γ-PGA compound(γ-PGA-ELA)ethanol solution can facilely produce colorless and transparent coatings on various inorganic,metal,and polymeric substrates,especially for the lumen of slender catheters(length up to 2 m,and inner diameter down to 1 mm).The functionalized γ-PGA coating presents remarkable antibacterial efficacy in vitro and in vivo.In addition,the γ-PGA compound is used as antibacterial additives of polyolefin via melting extrusion,and the asprepared antibacterial polyolefin demonstrates advantageous antibacterial efficacy.More importantly,the functionalized γ-PGA coating exhibit good hemocompatibility,low cytotoxicity,and satisfactory histocompatibility.The as-proposed γ-PGA compound has a great potential to serve as a safe and multifunctional antibacterial candidate to combat biomedical devices-related infections. 展开更多
关键词 Functionalized poly(γ-glutamic acid)compound Electrostatic assembly Antibacterial coating Antibacterial additive Catheter-associated infections
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