检索结果-南通市图书馆

Fluorescent carbon dots synthesized in solid phase and air for application in LEDs

nano Research 2024年第9期17卷 8495-8503页

作者： Wei-Jie Zheng Zhao-nan sun Yi-Ming Wang Huan-Ming Xiong Department of Chemistry and Shanghai Key Laboratory of Molecular Catalysis and Innovative Materials Fudan UniversityShanghai 200438China

Carbon dots(CDs)have been widely adopted as optical materials because of their excellent luminescent ***,most of the reported synthetic methods are conducted in solvents,especially hydrothermal/solvothermal reactions,leading to intractable problems such as toxic and flammable solvents,complex and inseparable by-products,and dangerously high pressures and ***-phase synthesis of CDs in air is an effective solution to overcome the above issues,but solid reactions always result in uncontrolled growth and agglomeration of *** this study,some inorganic salts are selected as catalysts for synthesizing CDs in solid states and air,which also play as dispersants to hinder CDs *** the meantime,some aromatic derivatives containing hydroxyl and amino groups are chosen as carbon sources,ground with the optimized catalyst,and then heated together in *** production yields are affected by the reaction time and reactant ratio,while the graphitization degrees of the CDs are determined by the reaction *** IG/ID value of their Raman spectra increases from 0.59 to 0.85,and the particle size decreases from 2.5 to 1.4 nm when the synthesis temperature is increased from 200 to 280℃.The as-prepared CDs show emission peaks ranging from 366 to 606 nm,with the photoluminescence(PL)quantum yield up to 53%.Their emission color variation mainly results from different carbon sources,which can be ascribed to the differences in the element composition,functional groups,and graphitic nitrogen content of these *** dispersing CDs of different concentrations into polyvinyl alcohol(PVA)and combining them with blue LEDs,cold,standard,and warm white light emitting devices(WLEDs)are prepared,with a color rendering index(CRI)up to *** the as-prepared CDs have antioxidant ability at high temperature,the as-prepared WLEDs have long lifespans,remaining the effective white luminescence after 72 h continuous work.

关键词： carbon dot solid-phase synthesis white LED photoluminescence inorganic salt catalysis

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Nomogram model including LATS2 expression was constructed to predict the prognosis of advanced gastric cancer after surgery

引用

World Journal of Gastrointestinal Surgery 2024年第2期16卷 518-528页

作者： nan sun Bi-Bo Tan Yong Li Department of Blood Transfusion The Fourth Hospital of Hebei Medical UniversityShijiazhuang 050011Hubei ProvinceChina Third Department of General Surgery the Fourth Hospital of Hebei Medical UniversityShijiazhuang 050011Hebei ProvinceChina

BACKGROUND Gastric cancer is a leading cause of cancer-related deaths *** assessments are typically based on the tumor-node-metastasis(TNM)staging system,which does not account for the molecular heterogeneity of this ***2,a tumor suppressor gene involved in the Hippo signaling pathway,has been identified as a potential prognostic biomarker in gastric *** To construct and validate a nomogram model that includes LATS2 expression to predict the survival prognosis of advanced gastric cancer patients following ra-dical surgery,and compare its predictive performance with traditional TNM *** A retrospective analysis of 245 advanced gastric cancer patients from the Fourth Hospital of Hebei Medical University was *** patients were divided into a training group(171 patients)and a validation group(74 patients)to deve-lop and test our prognostic *** performance of the model was determined using C-indices,receiver operating characteristic curves,calibration plots,and decision *** The model demonstrated a high predictive accuracy with C-indices of 0.829 in the training set and 0.862 in the validation *** under the curve values for three-year and five-year survival prediction were significantly robust,suggesting an excellent discrimination *** plots confirmed the high concordance between the predictions and actual survival *** We developed a nomogram model incorporating LATS2 expression,which significantly outperformed conven-tional TNM staging in predicting the prognosis of advanced gastric cancer patients *** model may serve as a valuable tool for individualized patient management,allowing for more accurate stratification and im-proved clinical *** validation in larger patient cohorts will be necessary to establish its generaliza-bility and clinical utility.

关键词： Gastric cancer LATS2 Column line graph Prognosis Advanced gastric cancer survival Molecular biomarkers Predictive analytics in oncology Survival analysis

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

A New Algorithm of Rain Type Classification for GPM Dual-Frequency Precipitation Radar in Summer Tibetan Plateau

引用

ADVANCES IN ATMOSPHERIC SCIENCES 2024年第11期41卷 2093-2111页

作者： Fu, Yunfei Yang, Liu Wu, Zhenhao Zhang, Peng Gu, Songyan Chen, Lin nan, sun Univ Sci & Technol China Sch Earth & Space Sci CMA USTC Lab Fengyun Remote Sensing Hefei 230026 Peoples R China China Meteorol Adm Inst Heavy Rain Hubei Key Lab Heavy Rain Monitoring & Warning Res Wuhan 430205 Peoples R China China Meteorol Adm Natl Satellite Meteorol Ctr Beijing 100081 Peoples R China

In this study, a new rain type classification algorithm for the Dual-Frequency Precipitation Radar (DPR) suitable over the Tibetan Plateau (TP) was proposed by analyzing Global Precipitation Measurement (GPM) DPR Level-2 data in summer from 2014 to 2020. It was found that the DPR rain type classification algorithm (simply called DPR algorithm) has mis-identification problems in two aspects in summer TP. In the new algorithm of rain type classification in summer TP, four rain types are classified by using new thresholds, such as the maximum reflectivity factor, the difference between the maximum reflectivity factor and the background maximum reflectivity factor, and the echo top height. In the threshold of the maximum reflectivity factors, 30 dBZ and 18 dBZ are both thresholds to separate strong convective precipitation, weak convective precipitation and weak precipitation. The results illustrate obvious differences of radar reflectivity factor and vertical velocity among the three rain types in summer TP, such as the reflectivity factor of most strong convective precipitation distributes from 15 dBZ to near 35 dBZ from 4 km to 13 km, and increases almost linearly with the decrease in height. For most weak convective precipitation, the reflectivity factor distributes from 15dBZ to 28 dBZ with the height from 4 km to 9 km. For weak precipitation, the reflectivity factor mainly distributes in range of 15-25 dBZ with height within 4-10 km. It is also shows that weak precipitation is the dominant rain type in summer TP, accounting for 40%-80%, followed by weak convective precipitation (25%-40%), and strong convective precipitation has the least proportion (less than 30%).

关键词： satellite precipitation radar rain type classification method Tibetan Plateau strong convective precipitation TRMM PR EAST-ASIA REANALYSIS SATELLITE CYCLE

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Rapid and stable calcium-looping solar thermochemical energy storage via co-doping binary sulfate and Al±Mn±Fe oxides

引用

Green Energy & Environment 2024年第8期9卷 1290-1305页

作者： Changjian Yuan Xianglei Liu Xinrui Wang Chao Song Hangbin Zheng Cheng Tian Ke Gao nan sun Zhixing Jiang Yimin Xuan Yulong Ding School of Energy and Power Engineering Nanjing University of Aeronautics and Astronautics Key Laboratory of Thermal Management and Energy Utilization of Aviation Vehicles Ministry of Industry and Information Technology Birmingham Centre for Energy Storage School of Chemical Engineering University of Birmingham

Solar thermochemical energy storage based on calcium looping（CaL） process is a promising technology for next-generation concentrated solar power（CSP） systems. However, conventional calcium carbonate（CaCO3） pellets suffer from slow reaction kinetics, poor stability, and low solar absorptance. Here, we successfully realized high power density and highly stable solar thermochemical energy storage/release by synergistically accelerating energy storage/release via binary sulfate and promoting cycle stability, mechanical strength, and solar absorptance via Al±Mn±Fe oxides. The energy storage density of proposed CaCO3pellets is still as high as 1455 kJ kg-1with only a slight decay rate of 4.91% over 100 cycles, which is higher than that of state-of-the-art pellets in the literature, in stark contrast to 69.9% of pure CaCO3pellets over 35cycles. Compared with pure CaCO3, the energy storage power density or decomposition rate is improved by 120% due to lower activation energy and promotion of Ca2+diffusion by binary sulfate. The energy release or carbonation rate rises by 10% because of high O2-transport ability of molten binary sulfate. Benefiting from fast energy storage/release rate and high solar absorptance, thermochemical energy storage efficiency is enhanced by more than 50% under direct solar irradiation. This work paves the way for application of direct solar thermochemical energy storage techniques via achieving fast energy storage/release rate, high energy density, good cyclic stability, and high solar absorptance simultaneously.

关键词： Calcium looping (CaL) Solar thermochemical Energy storage Binary sulfate Fast reaction kinetics

来源：

同方期刊数据库评论

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Efficient solar-driven CO_(2)-to-fuel conversion via Ni/MgAlO_(x)@SiO_(2)nanocomposites at low temperature

引用

Fundamental Research 2024年第1期4卷 131-139页

作者： Xianglei Liu Yueyue Ling Chen sun Hang Shi Hangbin Zheng Chao Song Ke Gao Chunzhuo Dang nan sun Yimin Xuan Yulong Ding School of Energy and Power Engineering Nanjing University of Aeronautics and AstronauticsNanjing 210016China Birmingham Centre for Energy Storage School of Chemical EngineeringUniversity of BirminghamBirmingham B152TTUnited Kingdom

Solar-driven CO_(2)-to-fuel conversion assisted by another major greenhouse gas CH_(4)is promising to concurrently tackle energy shortage and global warming ***,current techniques still suffer from drawbacks of low efficiency,poor stability,and low ***,a novel nanocomposite composed of interconnected Ni/MgAlOx nanoflakes grown on SiO_(2)particles with excellent spatial confinement of active sites is proposed for direct solar-driven CO_(2)-to-fuel *** ultrahigh light-to-fuel efficiency up to 35.7%,high production rates of H_(2)(136.6 mmol min^(-1)g^(-1))and CO(148.2 mmol min^(-1)g^(-1)),excellent selectivity(H_(2)/CO ratio of 0.92),and good stability are reported *** outstanding performances are attributed to strong metal-support interactions,improved CO_(2)absorption and activation,and decreased apparent activation energy under direct light ***_(x)@SiO_(2)support helps to lower the activation energy of CH^(*) oxidation to CHO^(*) and improve the dissociation of CH_(4)to CH_(3)^(*) as confirmed by DFT ***,the lattice oxygen of MgAlO_(x) participates in the reaction and contributes to the removal of carbon *** work provides promising routes for the conversion of greenhouse gasses into industrially valuable syngas with high efficiency,high selectivity,and benign sustainability.

关键词： Solar fuel CO_(2)reduction Dry reforming of methane Photothermocatalysis Stability

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

A New Algorithm of Rain Type Classification for GPM Dual-Frequency Precipitation Radar in Summer Tibetan Plateau

引用

Advances in Atmospheric Sciences 2024年第11期 2093-2111页

作者： Yunfei FU Liu YANG Zhenhao WU Peng ZHANG Songyan GU Lin CHEN sun nan School of Earth and Space Sciences CMA–USTC Laboratory of Fengyun Remote SensingUniversity of Science and Technology of China Hubei Key Laboratory for Heavy Rain Monitoring and Warning Research Institute of Heavy RainChina Meteorological Administration National Satellite Meteorological Center China Meteorological Administration

In this study, a new rain type classification algorithm for the Dual-Frequency Precipitation Radar(DPR) suitable over the Tibetan Plateau(TP) was proposed by analyzing Global Precipitation Measurement(GPM) DPR Level-2 data in summer from 2014 to 2020. It was found that the DPR rain type classification algorithm(simply called DPR algorithm) has mis-identification problems in two aspects in summer TP. In the new algorithm of rain type classification in summer TP,four rain types are classified by using new thresholds, such as the maximum reflectivity factor, the difference between the maximum reflectivity factor and the background maximum reflectivity factor, and the echo top height. In the threshold of the maximum reflectivity factors, 30 d BZ and 18 d BZ are both thresholds to separate strong convective precipitation, weak convective precipitation and weak precipitation. The results illustrate obvious differences of radar reflectivity factor and vertical velocity among the three rain types in summer TP, such as the reflectivity factor of most strong convective precipitation distributes from 15 d BZ to near 35 d BZ from 4 km to 13 km, and increases almost linearly with the decrease in height. For most weak convective precipitation, the reflectivity factor distributes from 15 d BZ to 28 d BZ with the height from 4 km to 9 km. For weak precipitation, the reflectivity factor mainly distributes in range of 15–25 d BZ with height within 4–10 km. It is also shows that weak precipitation is the dominant rain type in summer TP, accounting for 40%–80%,followed by weak convective precipitation(25%–40%), and strong convective precipitation has the least proportion(less than 30%).

关键词：

来源：

同方期刊数据库评论

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

基于全价值和全成本模型的农业水价方案及其可行性分析

引用

农业机械学报 2024年第5期55卷 356-367页

作者：成琨王子欣孙楠东北农业大学理学院哈尔滨150030 东北农业大学水利与土木工程学院哈尔滨150030

针对现行农业水价标准过低的问题,选取粮食主产区——黑龙江省为研究区域,从农业用水全价值和全成本出发,利用能值理论分析确定农业用水价值,采用全成本水价法确定用水成本,结合现行水价制定不同情境下农业水资源定价方案;运用双对数模... 详细信息

针对现行农业水价标准过低的问题,选取粮食主产区——黑龙江省为研究区域,从农业用水全价值和全成本出发,利用能值理论分析确定农业用水价值,采用全成本水价法确定用水成本,结合现行水价制定不同情境下农业水资源定价方案;运用双对数模型建立农业用水需求价格函数,揭示水价提升带来的研究区域节水潜力,结合指数分析法确定农户可承受能力,从而判断所制定水价方案的可行性。结果表明:2020年,农业水资源全价值为0.594元/m^(3),地表水与地下水全成本分别为0.180元/m^(3)和0.355元/m^(3);针对设计的3种阶梯水价调整方案,利用2005、2010、2015、2020年进行实证分析,过渡期和长期水价方案平均年节水量分别可达2.72×10^(9)、4.45×10^(9)m^(3),平均年节水潜力分别为12.74%、19.48%,且一阶水价均在农户可承受能力范围,确定为可行方案。本文为研究区农业水价综合改革提供了支持,可结合实际情况逐步提高农业水价到合理水平。

关键词：农业水价农业水资源全价值模型改进的全成本水价模型能值理论阶梯水价

来源：

维普期刊数据库博看期刊

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

基于Modis的黄土高原2001~2020年活跃火发生时空特征分析

引用

第四纪研究 2024年第1期44卷 191-200页

作者：郑昕馨孙楠罗凡长安大学地球科学与资源学院陕西西安710054 西北大学陕西省早期生命与环境重点实验室陕西西安710069

近年来随着全球气候变化,活跃火发生频次显著增加,在不同地区开展活跃火发生机制的研究对于理解活跃火演变规律至关重要。本研究基于黄土高原2001~2020年Modis火点数据和土地覆盖数据,利用ArcGIS、ENVI等软件绘制研究区火点分布图并进... 详细信息

近年来随着全球气候变化,活跃火发生频次显著增加,在不同地区开展活跃火发生机制的研究对于理解活跃火演变规律至关重要。本研究基于黄土高原2001~2020年Modis火点数据和土地覆盖数据,利用ArcGIS、ENVI等软件绘制研究区火点分布图并进行趋势分析,评估研究区的活跃火时空分布与土地覆盖类型之间的关系,探讨了黄土高原活跃火的时空规律,得到以下主要结论:1)黄土高原活跃火发生频次和强度空间分布格局相似,主要集中在黄河沿线以农田为主的东部平原,且强度较高,中西部活跃火分布相对较少,强度相对较低;2)黄土高原活跃火集中发生在春夏季,呈三峰分布,分别在春季3~4月、夏季6月和秋季10月达到峰值,其中3~4月草原火和森林火的贡献较大,而6月及10月农田火贡献最大;3)按土地覆盖类型进行分析,城市火和农田火是黄土高原地区活跃火发生的主要类型,占比可达总活跃火数量的69%,其次是草原火和森林火,说明黄土高原活跃火受人为因素影响较大;4)野火(包括草原火、森林火、灌木火和裸地火)主要集中在冬春季发生,城市火和农田火主要集中在夏秋季发生。近20年,由于研究区秸秆禁烧政策和城市的防火措施的实施,城市火和农田火呈减少趋势,冬春季的增温导致研究区野火呈增多趋势。

关键词： Modis 黄土高原气候变化活跃火时空特征

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

基于“血管-脏腑-证治”防治泛血管疾病的中医思考

引用

中国实验方剂学杂志 2024年第10期30卷 187-195页

作者：李军孙语男王阶中国中医科学院广安门医院北京100053 北京中医药大学附属护国寺中医医院北京100035

泛血管指人体血管系统,是动脉、静脉、淋巴管所构成的复杂网络,泛血管疾病指一组血管系统疾病,以血管粥样硬化为共同病理特征,因缺血或出血造成心、脑、肾、肢体等靶器官病变,具体包括动脉系统病变、静脉系统病变、微循环系统病变,及“... 详细信息

泛血管指人体血管系统,是动脉、静脉、淋巴管所构成的复杂网络,泛血管疾病指一组血管系统疾病,以血管粥样硬化为共同病理特征,因缺血或出血造成心、脑、肾、肢体等靶器官病变,具体包括动脉系统病变、静脉系统病变、微循环系统病变,及“血管-脏腑”“脏腑-血管”相关病变。泛血管疾病概念整合了血管病变及靶器官损伤。临床将多个区域血管融合成为广泛的血管单元系统,并将血管病变及其所致靶器官损伤视为整体,根据中医整体观念和藏象理论,构建“血管-脏腑-证治”之间的关联,应用“血管疾病-脏腑失调-辨证治疗”病证结合的诊疗模式,从中医学角度探讨泛血管疾病的诊疗方法。提出“动脉系统疾病从心治疗、静脉系统疾病从肾治疗、微血管系统疾病从肝治疗”的理论,审证求因,辨证论治,总结扶阳活血法(包括温阳活血法、益气活血法、益气养阴活血法、通阳活血法、散寒活血法)、凉血化瘀法、补肾利水-活血通脉法、滋阴补肾-活血通脉法、疏肝理气-活血通络法及“风药”的具体治法和临证应用,为中医药治疗血管疾病提供方法和思路。

关键词：泛血管泛血管疾病藏象理论血管-脏腑-证治中医治法

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

运用“清、宣、补、化”法辨治心力衰竭合并肺部感染

引用

中医杂志 2024年第6期65卷 645-648页

作者：李军孙语男中国中医科学院广安门医院北京市100053 北京中医药大学附属护国寺中医医院

心力衰竭合并肺部感染以心肺气虚、脾肾阳虚、气阴两虚为本,肺热、痰热、瘀血等邪气痼结为标,病性属正虚邪实、虚实夹杂,基本病机为气阴两虚、肺热痰瘀。据此提出心力衰竭合并肺部感染主要治法为清、宣、补、化法,“清”即根据邪热郁闭... 详细信息

心力衰竭合并肺部感染以心肺气虚、脾肾阳虚、气阴两虚为本,肺热、痰热、瘀血等邪气痼结为标,病性属正虚邪实、虚实夹杂,基本病机为气阴两虚、肺热痰瘀。据此提出心力衰竭合并肺部感染主要治法为清、宣、补、化法,“清”即根据邪热郁闭程度不同,分别予清热解表法、清营透热法、清热凉血法;“宣”主要为宣肺通腑法;“补”以甘温除热法、滋阴益气法、温阳化气法为主;“化”即根据不同病理产物分别予化痰祛湿法、活血化瘀法。

关键词：心力衰竭肺部感染清法宣法补法化法

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：