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我国大豆生产波动动因分析——基于省际面板模型的实证研究 被引量:6
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作者 李维刚 张晓东 +1 位作者 宋继华 孙丹 《农业经济与管理》 CSSCI 北大核心 2023年第2期48-63,共16页
在我国大豆生产波动频繁的情况下,找出影响大豆单产、种植面积的影响因素是实现“提单产、稳面积”的首要举措。研究采用1999~2020年21个省份面板数据,在分析大豆单产、种植面积的变化趋势基础上,根据大豆单产增减趋势,把大豆产区划分... 在我国大豆生产波动频繁的情况下,找出影响大豆单产、种植面积的影响因素是实现“提单产、稳面积”的首要举措。研究采用1999~2020年21个省份面板数据,在分析大豆单产、种植面积的变化趋势基础上,根据大豆单产增减趋势,把大豆产区划分成增产区、减产区和波动区,采用改进的面板数据模型分别对三个产区的大豆单产和种植面积的影响因素进行实证分析。结果表明,机械化收割、产研结合、农药投入、小型拖拉机的投入是影响不同区域大豆单产的显著因素;机械化耕作是提升所有区域种植面积的显著因素,玉米种植面积、化肥投入、农药投入、灌溉条件、科研资金与人员投入、产研结合、机械化收割是影响不同区域大豆种植面积显著因素。根据分析,提出了相应政策建议。 展开更多
关键词 大豆生产 大豆单产 大豆种植面积
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模型水轮机初生空化的特征谱提取识别方法 被引量:4
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作者 韩文福 倪晋兵 +5 位作者 桂中华 满哲 丁景焕 肖微 李东阔 汪刚 《水力发电学报》 CSCD 北大核心 2023年第8期69-79,共11页
目前水轮机模型初生空化识别方法仍采用人工识别法,这种方法获得结果的周期较长、主观性强、准确度及效率都较低。针对于此,对水轮机模型初生空化识别方法进行了研究与优化创新,提出了一种基于炮声谱与特殊脉动谱特征提取的水轮机空化... 目前水轮机模型初生空化识别方法仍采用人工识别法,这种方法获得结果的周期较长、主观性强、准确度及效率都较低。针对于此,对水轮机模型初生空化识别方法进行了研究与优化创新,提出了一种基于炮声谱与特殊脉动谱特征提取的水轮机空化智能识别方法,即多态泡音智能识别方法 PSVFR。该方法依据自主开发的水轮机空化噪声多态算法MTCSPC,对数据进行处理,通过采集初生空化音态特征向量,建立矩阵模型,与样本数据库中的定性矩阵进行特征比对、计算、判断,以帮助机器完成对模型水轮机空化噪声的学习和识别。与现有技术相比,该方法能够提高机器对水轮机初生空化现象的识别准确度和识别效率,识别效率可达80%。 展开更多
关键词 水轮机空化 空化识别 泡音智能识别 音态特征向量 特征谱
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基于YOLOv5改进的CBAM平贝母检测模型
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作者 滕煜 赵伟 +3 位作者 韩义勇 王耀申 王思博 宋江 《中国农机装备》 2023年第3期8-12,共5页
目前的平贝母种植阶段中,覆土仍然依靠人工,这存在耗时、耗力、成本高等问题。故需要研制一款智能化的平贝母覆土机器,而实现智能化的第一步在于实现识别。以YOLOv5系列为基础训练出一系列模型,在其系列中挑出最优模型(YOLOv5s)进行改进... 目前的平贝母种植阶段中,覆土仍然依靠人工,这存在耗时、耗力、成本高等问题。故需要研制一款智能化的平贝母覆土机器,而实现智能化的第一步在于实现识别。以YOLOv5系列为基础训练出一系列模型,在其系列中挑出最优模型(YOLOv5s)进行改进;进而在骨干段加入CBAM注意力机制替换其C3结合,从而减少网络序列长度,减少计算复杂度。试验结果表明,改进后模型的准确度最高可达91.32%,召回率最高可达88.78%。本文模型的提出为下一步实现平贝母覆土机智能控制提供理论参考。 展开更多
关键词 平贝母 YOLOv5 CBAM 注意力机制
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不同香型白酒在陶缸陈酿过程中的变化研究
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作者 祝成 蒋燕明 +9 位作者 管莹 易翔 左可成 万朕 柯锋 詹苏 孙婷婷 施鹏 罗高建 童国强 《酿酒科技》 2023年第11期70-76,共7页
为了弄清楚不同香型白酒在陶缸陈酿过程中的变化情况,更好地指导原酒的科学贮存,选取3种香型白酒(清香、浓香、酱香)分别放入陶缸中进行陈酿3年,研究3种香型白酒在陶缸陈酿过程中酒精度、金属元素、微量风味成分和感官风格的变化情况。... 为了弄清楚不同香型白酒在陶缸陈酿过程中的变化情况,更好地指导原酒的科学贮存,选取3种香型白酒(清香、浓香、酱香)分别放入陶缸中进行陈酿3年,研究3种香型白酒在陶缸陈酿过程中酒精度、金属元素、微量风味成分和感官风格的变化情况。随着储存时间的延长,酯类物质含量总体呈现下降趋势,三年左右趋于平衡,酸类物质缓慢增加,高级醇含量轻微下降;Na、K、Mg、Fe、Zn等金属元素显示出升高的趋势;感官评分呈一定的增加趋势。 展开更多
关键词 白酒 微量成分 陶缸陈酿
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白酒产业转型升级路径分析研究——以泸州为例
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作者 韩保林 王宇 +8 位作者 张怀山 王跃 龚虎程 田树林 杨燕 周林川 任啸虎 张淑凡 韦易涵 《酿酒科技》 2023年第11期130-134,共5页
白酒产业是泸州市特色优势产业,为泸州经济社会发展做出了重要贡献。进入“十四五”时期,泸州市白酒产业面临白酒产业政策调整、新冠肺炎疫情、中美贸易争端以及中国加快构建“双循环”新发展格局等机遇和挑战。为探究新形势下泸州市白... 白酒产业是泸州市特色优势产业,为泸州经济社会发展做出了重要贡献。进入“十四五”时期,泸州市白酒产业面临白酒产业政策调整、新冠肺炎疫情、中美贸易争端以及中国加快构建“双循环”新发展格局等机遇和挑战。为探究新形势下泸州市白酒制造业转型升级路径,本研究通过梳理文献、深入调研、座谈等方法,从行业发展的角度入手,系统梳理相关文献,对泸州白酒产业现状、面临形势进行了分析,并在此基础上提出了创新发展、绿色发展、融合发展三个方面的建议。 展开更多
关键词 泸州 白酒产业 升级
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复方银黄微型灌肠剂对发热大鼠下丘脑前列腺素E_2受体表达的影响 被引量:3
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作者 何惠 刘华钢 +1 位作者 庞辉 朱丹 《中药药理与临床》 CAS CSCD 北大核心 2007年第2期50-52,共3页
目的:观察复方银黄微型灌肠剂(YHCE)对发热大鼠下丘脑中前列腺素E2受体EP1、EP4mRNA表达的影响。方法:大鼠皮下注射20%酵母混悬液造发热模型,复方银黄微型灌肠剂按35.84g/kg于造模1h后灌肠给药;给药后4h取大鼠下丘脑组织,用实时荧光定... 目的:观察复方银黄微型灌肠剂(YHCE)对发热大鼠下丘脑中前列腺素E2受体EP1、EP4mRNA表达的影响。方法:大鼠皮下注射20%酵母混悬液造发热模型,复方银黄微型灌肠剂按35.84g/kg于造模1h后灌肠给药;给药后4h取大鼠下丘脑组织,用实时荧光定量聚合酶链反应检测各组大鼠下丘脑中EP1、EP4受体mRNA表达的相对差异。结果:与发热对照组比,YHCE组的EP1、EP4受体mRNA相对表达量减少。结论:复方银黄微型灌肠剂可抑制发热组大鼠下丘脑中前列腺素E受体EP1、EP4mRNA的表达。 展开更多
关键词 复方银黄微灌肠剂 发热 前列腺素E 受体
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Enhancing rock fragmentation prediction in mining operations:A hybrid GWO-RF model with SHAP interpretability 被引量:1
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作者 ZHANG Yu-lin QIU Yin-gui +2 位作者 ARMAGHANI Danial Jahed MONJEZI Masoud ZHOU Jian 《Journal of Central South University》 SCIE EI CAS CSCD 2024年第8期2916-2929,共14页
In the mining industry,precise forecasting of rock fragmentation is critical for optimising blasting processes.In this study,we address the challenge of enhancing rock fragmentation assessment by developing a novel hy... In the mining industry,precise forecasting of rock fragmentation is critical for optimising blasting processes.In this study,we address the challenge of enhancing rock fragmentation assessment by developing a novel hybrid predictive model named GWO-RF.This model combines the grey wolf optimization(GWO)algorithm with the random forest(RF)technique to predict the D_(80)value,a critical parameter in evaluating rock fragmentation quality.The study is conducted using a dataset from Sarcheshmeh Copper Mine,employing six different swarm sizes for the GWO-RF hybrid model construction.The GWO-RF model’s hyperparameters are systematically optimized within established bounds,and its performance is rigorously evaluated using multiple evaluation metrics.The results show that the GWO-RF hybrid model has higher predictive skills,exceeding traditional models in terms of accuracy.Furthermore,the interpretability of the GWO-RF model is enhanced through the utilization of SHapley Additive exPlanations(SHAP)values.The insights gained from this research contribute to optimizing blasting operations and rock fragmentation outcomes in the mining industry. 展开更多
关键词 BLASTING rock fragmentation random forest grey wolf optimization hybrid tree-based technique
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乙型肝炎病毒SYBR GreenⅠ实时荧光定量PCR方法的建立及临床应用 被引量:6
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作者 何维娜 吕东月 +3 位作者 刘和录 韩杰辉 何玥 李培培 《现代检验医学杂志》 CAS 2016年第3期98-101,共4页
目的建立 SYBR Green I实时荧光定量 PCR检测乙型肝炎病毒 DNA的快速方法,并探讨其临床应用价值。方法根据GenBank公布的Hepatitis B virus gp1基因序列设计引物,建立SYBR Green I实时荧光定量PCR,并对反应体系和扩增程序进行优化。... 目的建立 SYBR Green I实时荧光定量 PCR检测乙型肝炎病毒 DNA的快速方法,并探讨其临床应用价值。方法根据GenBank公布的Hepatitis B virus gp1基因序列设计引物,建立SYBR Green I实时荧光定量PCR,并对反应体系和扩增程序进行优化。定量标准品通过基因克隆方法获得,同时以浙江省夸克公司 HBV DNA定量检测试剂盒作对照,应用于随机选取的100份乙型肝炎患者血清检测。结果 SYBR Green I 实时荧光定量 PCR 检出限范围为5&#215;102 copies/ml~5&#215;108 copies/ml,HBV DNA浓度与CT值有良好线性关系,无交叉反应,整个过程仅需2.5 h。在随机抽取的100份临床标本应用中,与浙江省夸克公司的 HBV荧光定量 PCR检测试剂相比,建立的 SYBR Green I实时荧光定量PCR体系灵敏度100%,特异度92.5%。结论 SYBR Green实时荧光定量PCR快速、简便、灵敏度高、特异度强,可用于乙型肝炎患者病情监测,有效指导临床用药,准确评价 HBV感染者的病情。 展开更多
关键词 SYBR Green I实时荧光定量PCR 肝炎病毒DNA 快速检测 公司产品对比
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A study on the simulation of carbon and water fluxes of Dangxiong alpine meadow and its response to climate change 被引量:1
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作者 Lingyun He Lei Zhong +3 位作者 Yaoming Ma Yuting Qi Jie Liu Peizhen Li 《Atmospheric and Oceanic Science Letters》 CSCD 2024年第5期22-27,共6页
The alpine meadow ecosystem accounts for 27%of the total area of the Tibetan Plateau and is also one of the most important vegetation types.The Dangxiong alpine meadow ecosystem,located in the south-central part of th... The alpine meadow ecosystem accounts for 27%of the total area of the Tibetan Plateau and is also one of the most important vegetation types.The Dangxiong alpine meadow ecosystem,located in the south-central part of the Tibetan Plateau,is a typical example.To understand the carbon and water fluxes,water use efficiency(WUE),and their responses to future climate change for the alpine meadow ecosystem in the Dangxiong area,two parameter estimation methods,the Model-independent Parameter Estimation(PEST)and the Dynamic Dimensions Search(DDS),were used to optimize the Biome-BGC model.Then,the gross primary productivity(GPP)and evapotranspiration(ET)were simulated.The results show that the DDS parameter calibration method has a better performance.The annual GPP and ET show an increasing trend,while the WUE shows a decreasing trend.Meanwhile,ET and GPP reach their peaks in July and August,respectively,and WUE shows a“dual-peak”pattern,reaching peaks in May and November.Furthermore,according to the simulation results for the next nearly 100 years,the ensemble average GPP and ET exhibit a significant increasing trend,and the growth rate under the SSP5–8.5 scenario is greater than that under the SSP2–4.5 scenario.WUE shows an increasing trend under the SSP2–4.5 scenario and a significant increasing trend under the SSP5–8.5 scenario.This study has important scientific significance for carbon and water cycle prediction and vegetation ecological protection on the Tibetan Plateau. 展开更多
关键词 Carbon and water flux Water use efficiency Alpine meadow Biome-BGC model Climate change
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幼龄贵州小型猪体重与各脏器重量之间关系的回归分析 被引量:5
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作者 钱宁 郭科男 +3 位作者 吴曙光 董小君 巫全胜 赵菊花 《贵阳中医学院学报》 2007年第5期12-14,共3页
目的:测定幼龄贵州小型猪脏器重量、脏器系数的生物学特性指标,对体重与各脏器重量之间的关系进行了回归分析,并计算出相应的直线回归方程。方法:选用初生和一月龄贵州小型猪各20只,雌雄各半,分别测定体重和10个脏器重量,计算脏器系数,... 目的:测定幼龄贵州小型猪脏器重量、脏器系数的生物学特性指标,对体重与各脏器重量之间的关系进行了回归分析,并计算出相应的直线回归方程。方法:选用初生和一月龄贵州小型猪各20只,雌雄各半,分别测定体重和10个脏器重量,计算脏器系数,对脏体比与体重作相关性分析。结果:雌雄贵州小型猪初生组体重、肝重量、肾重量、胃系数差异均有极显著性(P<0.01),胃重量、心重量有显著性差异(P<0.05),而一月龄组雌雄体重和脏器重量差异均无显著性(P>0.05),肺系数差异有极显著性(P<0.01);雄性贵州小型猪体重与肝、胆囊、胃、心、肺、肾、脾、肾、脾、肾上腺、睾丸(P<0.01),两样本间有线性关系。雌性贵州小型猪体重与肝、胆囊、胃、心、肺、肾、脾、肾、脾、肾上腺(P<0.01),两样本间有线性关系。卵巢(P>0.05),两样本间无线性关系。结论:本研究填补了国内有关贵州小型猪脏器重量、脏器系数测定的空白,为相关研究打下基础。 展开更多
关键词 贵州小 体重 脏器重量 脏器系数
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《型世言》动词重叠的格式与特点 被引量:6
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作者 贺卫国 《河池学院学报》 2005年第3期83-86,共4页
《型世言》共使用15式257例动词重叠,单音节动词重叠“V一V”式最多,双音节动词重叠“AABB”格式最多,“AB—AB”格式次多。《型世言》有的动词重叠带补语,有的带“着”等助词性成分,但极少带“儿”尾,名词性成分作宾语时全部后置。弄... 《型世言》共使用15式257例动词重叠,单音节动词重叠“V一V”式最多,双音节动词重叠“AABB”格式最多,“AB—AB”格式次多。《型世言》有的动词重叠带补语,有的带“着”等助词性成分,但极少带“儿”尾,名词性成分作宾语时全部后置。弄清《型世言》动词重叠的这些特点,对于我们研究动词重叠的发展史具有重要意义。 展开更多
关键词 世言》 动词重叠 重叠格式 语法特点
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导泻解毒方治疗急性有机磷农药中毒毒热蕴结型的临床研究 被引量:6
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作者 张丹 《中医临床研究》 2019年第8期120-122,共3页
目的:探讨中药导泻解毒方在急性有机磷农药中毒中的疗效。方法:选择口服急性有机磷农药中毒住院患者166例,随机分为实验组(56例)、生大黄粉组(55例)、甘露醇组(55例)。三组患者均应用常规治疗,实验组在此基础上加用中药导泻解毒方;生大... 目的:探讨中药导泻解毒方在急性有机磷农药中毒中的疗效。方法:选择口服急性有机磷农药中毒住院患者166例,随机分为实验组(56例)、生大黄粉组(55例)、甘露醇组(55例)。三组患者均应用常规治疗,实验组在此基础上加用中药导泻解毒方;生大黄粉组加用生大黄粉;甘露醇组加用甘露醇,均从胃管内注入以导泻排毒,观察三组患者的临床疗效。结果:三组患者在长托宁用药次数,首次排便时间,每日排便次数,心肌酶、肝功及血清胆碱酯酶(ChE)恢复时间,症状消失时间,住院时间比较,实验组均优于生大黄粉组及甘露醇组,而生大黄粉组又优于甘露醇组(P <0.05)。结论:急性有机磷农药中毒患者在常规治疗的基础上加用中药导泻解毒方,可明显加速肠道残存农药的排泄,减少并发症,较快改善临床症状,缩短住院天数,降低反跳率及病死率,值得临床推广应用。 展开更多
关键词 导泻解毒方 急性有机磷农药中毒 毒热蕴结
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Bearing mechanism of roof and rib support structure in automatically formed roadway and its support design method
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作者 JIANG Bei WANG Ming-zi +4 位作者 WANG Qi XIN Zhong-xin XING Xue-yang DENG Yu-song YAO Liang-di 《Journal of Central South University》 SCIE EI CAS CSCD 2024年第7期2467-2487,共21页
Non-pillar mining technology with automatically formed roadway is a new mining method without coal pillar reservation and roadway excavation.The stability control of automatically formed roadway is the key to the succ... Non-pillar mining technology with automatically formed roadway is a new mining method without coal pillar reservation and roadway excavation.The stability control of automatically formed roadway is the key to the successful application of the new method.In order to realize the stability control of the roadway surrounding rock,the mechanical model of the roof and rib support structure is established,and the influence mechanism of the automatically formed roadway parameters on the compound force is revealed.On this basis,the roof and rib support structure technology of confined lightweight concrete is proposed,and its mechanical tests under different eccentricity are carried out.The results show that the bearing capacity of confined lightweight concrete specimens is basically the same as that of ordinary confined concrete specimens.The bearing capacity of confined lightweight concrete specimens under different eccentricities is 1.95 times higher than those of U-shaped steel specimens.By comparing the test results with the theoretical calculated results of the confined concrete,the calculation method of the bearing capacity for the confined lightweight concrete structure is selected.The design method of confined lightweight concrete support structure is established,and is successfully applied in the extra-large mine,Ningtiaota Coal Mine,China. 展开更多
关键词 automatically roadway with non-pillar confined lightweight concrete roof and rib support mechanical model bearing behaviour
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Investigation on p-type doping of PBn unipolar barrier InAsSb photodetectors
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作者 ZHANG Jian CHANG Chao +11 位作者 LI Hong-Fu SHI Yu-Na YIN Han-Xiang LI Yan-Hui YUE Biao WANG Hai-Peng YAN Chang-Shan DAI Xin-Ran DENG Gong-Rong KONG Jin-Cheng ZHAO Peng ZHAO Jun 《红外与毫米波学报》 SCIE EI CAS CSCD 北大核心 2024年第4期472-478,共7页
The lattice-matched XBn structures of InAsSb,grown on GaSb substrates,exhibit high crystal quali⁃ty,and can achieve extremely low dark currents at high operating temperatures(HOT).Its superior performance is attribute... The lattice-matched XBn structures of InAsSb,grown on GaSb substrates,exhibit high crystal quali⁃ty,and can achieve extremely low dark currents at high operating temperatures(HOT).Its superior performance is attributed to the unipolar barrier,which blocks the majority carriers while allowing unhindered hole transport.To further explore the energy band and carrier transport mechanisms of the XBn unipolar barrier structure,this pa⁃per systematically investigates the influence of doping on the dark current,photocurrent,and tunneling character⁃istics of InAsSb photodetectors in the PBn structure.Three high-quality InAsSb samples with unintentionally doped absorption layers(AL)were prepared,with varying p-type doping concentrations in the GaSb contact layer(CL)and the AlAsSb barrier layer(BL).As the p-type doping concentration in the CL increased,the device’s turn-on bias voltage also increased,and p-type doping in the BL led to tunneling occurring at lower bias voltages.For the sample with UID BL,which exhibited an extremely low dark current of 5×10^(-6) A/cm^(2).The photocurrent characteristics were well-fitted using the back-to-back diode model,revealing the presence of two opposing space charge regions on either side of the BL. 展开更多
关键词 INASSB PBN p-type doping dark current
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《型世言》语词札记 被引量:1
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作者 陈国华 《古籍整理研究学刊》 2004年第6期73-76,共4页
本文结合其他文献材料考释《型世言》中的八条语词,其中有的未经前人解释,有的虽经前 人解释但未为圆满,注重探求词义源流,并揭示了一些语义现象。
关键词 世言》 词义 考释
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Enhancing Photocatalytic Hydrogen Evolution through Electronic Structure and Wettability Adjustment of ZnIn_(2)S_(4)/Bi_(2)O_(3) S-Scheme Heterojunction
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作者 Linfeng Xiao Wanlu Ren +4 位作者 Shishi Shen Mengshan Chen Runhua Liao Yingtang Zhou Xibao Li 《物理化学学报》 SCIE CAS CSCD 北大核心 2024年第8期50-63,共14页
The production of renewable fuels through water splitting via photocatalytic hydrogen production holds significant promise.Nonetheless,the sluggish kinetics of hydrogen evolution and the inadequate water adsorption on... The production of renewable fuels through water splitting via photocatalytic hydrogen production holds significant promise.Nonetheless,the sluggish kinetics of hydrogen evolution and the inadequate water adsorption on photocatalysts present notable challenges.In this study,we have devised a straightforward hydrothermal method to synthesize Bi_(2)O_(3)(BO)derived from metal‐organic frameworks(MOFs),loaded with flower-like ZnIn_(2)S_(4)(ZIS).This approach substantially enhances water adsorption and surface catalytic reactions,resulting in a remarkable enhancement of photocatalytic activity.By employing triethanolamine(TEOA)as a sacrificial agent,the hydrogen evolution rate achieved with 15%(mass fraction)ZIS loading on BO reached an impressive value of 1610μmol∙h^(−1)∙g^(−1),marking a 6.34-fold increase compared to that observed for bare BO.Furthermore,through density functional theory(DFT)and ab initio molecular dynamics(AIMD)calculations,we have identified the reactions occurring at the ZIS/BO S-scheme heterojunction interface,including the identification of active sites for water adsorption and catalytic reactions.This study provides valuable insights into the development of high-performance composite photocatalytic materials with tailored electronic properties and wettability. 展开更多
关键词 S-scheme Hydrogen evolution WETTABILITY PHOTOCATALYSIS Electronic structure
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Is platinum-loaded titania the best material for dye-sensitized hydrogen evolution under visible light?
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作者 Haruka Yamamoto Langqiu Xiao +5 位作者 Yugo Miseki Hiroto Ueki Megumi Okazaki Kazuhiro Sayama Thomas E.Mallouk Kazuhiko Maeda 《Chinese Journal of Catalysis》 SCIE CAS CSCD 2024年第8期124-132,共9页
A dye-sensitized photocatalyst combining Pt-loaded TiO_(2) and Ru(Ⅱ)tris-diimine sensitizer(RuP)was constructed and its activity for photochemical hydrogen evolution was compared with that of Pt-intercalated HCa_(2)N... A dye-sensitized photocatalyst combining Pt-loaded TiO_(2) and Ru(Ⅱ)tris-diimine sensitizer(RuP)was constructed and its activity for photochemical hydrogen evolution was compared with that of Pt-intercalated HCa_(2)Nb_(3)O_(10) nanosheets.When the sacrificial donor ethylenediaminetetraacetic acid(EDTA)disodium salt dihydrate was used,RuP/Pt/TiO_(2) showed higher activity than RuP/Pt/HCa_(2)Nb_(3)O_(10).In contrast,when NaI(a reversible electron donor)was used,RuP/Pt/TiO_(2) showed little activity due to back electron transfer to the electron acceptor(I_(3)-),which was gener-ated as the oxidation product of I-.By modification with anionic polymers(sodium poly(styrenesulfonate)or sodium polymethacrylate)that could inhibit the scavenging of conduction band electrons by I_(3)-,the H_(2) production activity from aqueous NaI was improved,but it did not exceed that of RuP/Pt/HCa_(2)Nb_(3)O_(10).Transient absorption measurements showed that the rate of semiconductor-to-dye back electron transfer was slower in the case of TiO_(2) than HCa_(2)Nb_(3)O_(10),but the electron transfer reaction to I3-was much faster.These results indicate that Pt/TiO_(2) is useful for reactions with sacrificial reductants(e.g.,EDTA),where the back electron transfer reaction to the more reducible product can be neglected.However,more careful design of the catalyst will be nec-essary when a reversible electron donor is employed. 展开更多
关键词 Artificial photosynthesis Solar fuel Water splitting Z-scheme
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Advancing automated pupillometry:a practical deep learning model utilizing infrared pupil images
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作者 Dai Guangzheng Yu Sile +2 位作者 Liu Ziming Yan Hairu He Xingru 《国际眼科杂志》 CAS 2024年第10期1522-1528,共7页
AIM:To establish pupil diameter measurement algorithms based on infrared images that can be used in real-world clinical settings.METHODS:A total of 188 patients from outpatient clinic at He Eye Specialist Shenyang Hos... AIM:To establish pupil diameter measurement algorithms based on infrared images that can be used in real-world clinical settings.METHODS:A total of 188 patients from outpatient clinic at He Eye Specialist Shenyang Hospital from Spetember to December 2022 were included,and 13470 infrared pupil images were collected for the study.All infrared images for pupil segmentation were labeled using the Labelme software.The computation of pupil diameter is divided into four steps:image pre-processing,pupil identification and localization,pupil segmentation,and diameter calculation.Two major models are used in the computation process:the modified YoloV3 and Deeplabv 3+models,which must be trained beforehand.RESULTS:The test dataset included 1348 infrared pupil images.On the test dataset,the modified YoloV3 model had a detection rate of 99.98% and an average precision(AP)of 0.80 for pupils.The DeeplabV3+model achieved a background intersection over union(IOU)of 99.23%,a pupil IOU of 93.81%,and a mean IOU of 96.52%.The pupil diameters in the test dataset ranged from 20 to 56 pixels,with a mean of 36.06±6.85 pixels.The absolute error in pupil diameters between predicted and actual values ranged from 0 to 7 pixels,with a mean absolute error(MAE)of 1.06±0.96 pixels.CONCLUSION:This study successfully demonstrates a robust infrared image-based pupil diameter measurement algorithm,proven to be highly accurate and reliable for clinical application. 展开更多
关键词 PUPIL infrared image algorithm deep learning model
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The preparation and properties of N-doped carbon materials and their use for sodium storage
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作者 YUAN Ren-lu HOU Ruo-yang +4 位作者 SHANG Lei LIU Xue-wei LI Ang CHEN Xiao-hong SONG Huai-he 《新型炭材料(中英文)》 SCIE EI CAS CSCD 北大核心 2024年第5期770-795,共26页
Defect engineering by heteroatom doping gives carbon materials some new characteristics such as a different electronic structure and a high electrochemical activity,making them suitable for high-performance applicatio... Defect engineering by heteroatom doping gives carbon materials some new characteristics such as a different electronic structure and a high electrochemical activity,making them suitable for high-performance applications.N-doping has been widely investigated because of its similar atom radius to carbon,high electronegativity as well as many different configurations.We summarize the preparation methods and properties of N-doped carbon materials,and discuss their possible use in sodium ion storage.The relationships between N content/configuration and crystallinity,electronic conductivity,wettability,chemical reactivity as well as sodium ion storage performance are discussed. 展开更多
关键词 N-doped carbon material N configuration Preparation method Performance Sodium storage
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Effects of Storage Time and Hydrogen Peroxide on the Formation of Soy Globulin 15S in 11S Dilute Solutions Investigated by Analytical Ultracentrifugation
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作者 Hehang Shi Xiaodong Ye 《Chinese Journal of Chemical Physics》 SCIE EI CAS CSCD 2024年第4期563-570,I0095,共9页
Two soy protein 11S fractions with different surface sulfhydryl contents were prepared.Utilizing analytical ultracentrifugation,the effects of storage time and hydrogen peroxide at different concentrations(0.5-100 mmo... Two soy protein 11S fractions with different surface sulfhydryl contents were prepared.Utilizing analytical ultracentrifugation,the effects of storage time and hydrogen peroxide at different concentrations(0.5-100 mmol/L)on the two 11S fractions were investigated.Results show that after removing 2-mercaptoethanol(2-ME)by size exclusion chromatography,the 11S fraction with high surface sulfhydryl content(2.0 mol sulfhydryl/mol 11S)progressively formed 15S and 21S in dilute solutions during storage at 4℃ for 82 days.While,the 11s fraction with low surface sulfhydryl content(0.2 mol sulfhydryl/mol 11S)was stable under the same condition.Moreover,after treating the 11s with high surface sulfhydryl content with 1 mmol/L H_(2)O_(2),the weight percentage of 15S reached the maximum value of 20%.The 15S induced by air and H_(2)O_(2)could be totally converted to 11S with the addition of 10 mmol/L 2-ME,which could be attributed to that the disulfide bond linking two 11S molecules is on the surface of the 15S and easily accessible to the reducing agent 2-ME.This study helps us to deeply understand the formation mechanism of 15S and the stability of 11S. 展开更多
关键词 SOYBEAN 15S globulin 11S Analytical ultracentrifugation Hydrogen peroxide
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