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我国黑土粮仓正面临极端水文干旱加剧的威胁 被引量:2
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作者 刘孟竹 郭英 +6 位作者 张晓龙 沈彦军 张玉翠 裴宏伟 闵雷雷 王仕琴 沈彦俊 《Science Bulletin》 SCIE EI CAS CSCD 2023年第5期481-484,M0003,M0004,共6页
黑土粮仓是中国粮食安全的“压舱石”.近几十年频现的水文干旱对黑土粮仓粮食生产和生态安全造成了极大影响,然而目前该区水文干旱的变化机制仍未被很好地揭示.本研究使用GRACE卫星数据并结合3种机器学习模型,重建了黑土粮仓(主要研究... 黑土粮仓是中国粮食安全的“压舱石”.近几十年频现的水文干旱对黑土粮仓粮食生产和生态安全造成了极大影响,然而目前该区水文干旱的变化机制仍未被很好地揭示.本研究使用GRACE卫星数据并结合3种机器学习模型,重建了黑土粮仓(主要研究区为松花江流域)近60年(1960~2020年)的水储量变化并揭示了水文干旱规律.结果显示,尽管观测期内(2002~2020年)水储量在增加(+4 mm/a),但平均水储量仍低于重建时期(1960~2002年)水平.近20年的水文干旱相比于历史时期愈加频繁和极端,最近10年的多雨期甚至也出现了以往少雨期才有的异常水文干旱事件.随着下一个少雨期的到来,未来的极端水文干旱将会进一步加剧,这给当地的农业和生态安全带来了极大威胁.我们呼吁相关管理者重视该地区极端水文干旱事件频发并加剧的现象,及时制定应对预案来保障我国黑土粮仓的生态与粮食安全. 展开更多
关键词 粮食安全 水文干旱 生态安全 松花江流域 粮仓 多雨期 变化机制 黑土
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Aggregation-induced emission artificial enzyme(AIEzyme)with DNase-like activity:Imaging and matrix cleavage for combating bacterial biofilm
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作者 Lei Han yucui zhang +2 位作者 Baojian Huang Xuhui Bian Ben Zhong Tang 《Aggregate》 2023年第5期161-173,共13页
DNase-catalyzed hydrolysis of extracellular DNA(eDNA)has been widely employed to eradicate intractable biofilms.Although aggregation-induced emission(AIE)has become the ideal tool for killing planktonic bacteria,AIE l... DNase-catalyzed hydrolysis of extracellular DNA(eDNA)has been widely employed to eradicate intractable biofilms.Although aggregation-induced emission(AIE)has become the ideal tool for killing planktonic bacteria,AIE luminogens(AIEgens)often lack DNase-mimetic activity,so as to suffer from poor anti-biofilm capacity.Here,an“AIEzyme”,a kind of AIE nanomaterial with enzyme-like activity,is designed and synthesized,where the AIEgens are used as the ligands of Zr-based coordination polymer nanoparticles.Not only does AIEzyme have enduring DNasemimetic activity with low activation energy,but also structural rigidity-stabilized fluorescence.Due to the long-acting hydrolysis for eDNA in biofilm,AIEzyme can efficiently disorganize the established biofilms with good penetrability and realize the healing of superbug-infected wounds under only one dose of AIEzyme.This work provides a strategy to endow ordinary AIEgens with DNase-like and antibiofilm activities.Moreover,AIEzymes can be observed by virtue of their own AIE character,facilitating the study on self-positioning and residual amount of AIEzymes in wounds.The concept“AIEzyme”would hopefully stimulate the tremendous expansion for the tool kits and the application of AIEgens and artificial enzymes. 展开更多
关键词 aggregation-induced emission artificial enzyme BIOFILM DNASE extracellular DNA
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Screening and field application of microbial-flooding activator systems
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作者 Xiutian Yao Lipeng Gai +6 位作者 Yun Feng Runlin Zhao Yang Gao yucui zhang Chuanzhi Cui Jun Ma Zhongwei Wu 《Energy Geoscience》 EI 2024年第2期14-20,共7页
This study aims to further enhance the oil recovery of reservoirs in the Zhong-2 Block of the Gudao Oilfield by identifying the most effective microbial-flooding activator systems and applying them in the field.We beg... This study aims to further enhance the oil recovery of reservoirs in the Zhong-2 Block of the Gudao Oilfield by identifying the most effective microbial-flooding activator systems and applying them in the field.We began by analyzing the structure of the reservoirs'endogenous microbial communities to understand the potential impact of microbial flooding.This was followed by determining commonly used activator systems based on their abilities to stimulate oil-displacement functional bacteria.Through laboratory experiments on oil displacement efficiency and sweep characteristics,we determined the optimal activator injection method(injection ratio)and the requisite bacterial concentration for maximal microbial-flooding efficacy.Finally,we selected the optimal activator systems and applied them to field tests.Our findings suggest the target block is highly receptive to microbial-flooding.In terms of performance,the activator systems ranked as No.3>No.4>No.1>No.2.Interestingly,a deep activator system,when compared to the top-performing No.3 system,exhibited a higher bacterial concentration peak and longer peaking duration.Optimal oil displacement effects were observed at a 1:4 vol ratio between the No.3 activator and deep activator systems,with bacterial concentrations of up to 106 cells/mL or above.Field tests with the selected activator systems,following a specific injection protocol,demonstrated a notable increase in oil production and a reduction in water cut. 展开更多
关键词 Zhong-2 Block of Gudao Oilfield Microbial flooding Laboratory experiment Screening of activator system Field application
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Comparison of winter wheat yield sensitivity to climate variables under irrigated and rain-fed conditions 被引量:4
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作者 Dengpan XIAO Yanjun SHEN +6 位作者 He zhang Juana P. MOIWO Yongqing QI Rende WANG Hongwei PEI yucui zhang Huitao SHEN 《Frontiers of Earth Science》 SCIE CAS CSCD 2016年第3期444-454,共11页
Crop simulation models provide alternative, less time-consuming, and cost-effective means of deter- mining the sensitivity of crop yield to climate change. In this study, two dynamic mechanistic models, CERES (Crop E... Crop simulation models provide alternative, less time-consuming, and cost-effective means of deter- mining the sensitivity of crop yield to climate change. In this study, two dynamic mechanistic models, CERES (Crop Environment Resource Synthesis) and APSIM (Agricultural Production Systems Simulator), were used to simulate the yield of wheat (Triticum aestivum L.) under well irrigated (CFG) and rain-fed (YY) conditions in relation to different climate variables in the North China Plain (NCP). The study tested winter wheat yield sensitivity to different levels of temperature, radiation, precipitation, and atmospheric carbon dioxide (COa) concentration under CFG and YY conditions at Luancheng Agro-ecosystem Experimental Stations in the NCR The results from the CERES and APSIM wheat crop models were largely consistent and suggested that changes in climate variables influenced wheat grain yield in the NCR There was also significant variation in the sensitivity of winter wheat yield to climate variables under different water (CFG and YY) conditions. While a temperature increase of 2℃ was the threshold beyond which temperature negatively influenced wheat yield under CFG, a temperature rise exceeding 1℃ decreased winter wheat grain yield under YY. A decrease in solar radiation decreased wheat grain yield under both CFG and YY conditions. Although the sensitivity of winter wheat yield to precipitation was small under the CFG, yield decreased significantly with decreasing precipitation under the rain- fed YY treatment. The results also suggest that wheat yield under CFG linearly increased by ≈ 3.5% per 60 ppm (parts per million) increase in CO2 concentration from 380 to560ppm, and yield under YY increased linearly by ≈ 7.0% for the same increase in CO2 concentration. 展开更多
关键词 winter wheat yield sensitivity climate vari-ables crop model North China Plain
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