检索结果-南通市图书馆

Impacts of Regional-Scale Land Use/Land Cover Change on Diurnal Temperature Range

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

Advances in Climate Change Research 2013年第3期4卷 166-172页

作者： hua wen-Jian CHEN Hai-Shan Key Laboratory of Meteorological Disaster Ministry of Education Nanjing University of Information Science & Technology

The NCAR Community Atmosphere Model(CAM4.0)was used to investigate the climate efects of land use/land cover change(LUCC).Two simulations,one with potential land cover without significant human intervention and the other with current land use,were *** show that the impacts of LUCC on diurnal temperature range(DTR)are more significant than on mean surface air *** global average annual DTR change due to LUCC is–0.1℃,which is three times as large as the mean temperature *** influences regional DTR as simulated by the *** the mid-latitudes,LUCC leads to a decrease in DTR,which is mainly caused by the reduction in daily maximum ***,there are some diferences in the low *** reduction in DTR in East Asia is mainly the result of the decrease in daily maximum temperature,while in India,the decrease in DTR is due to the increase in daily minimum *** general,the LUCC significantly controls the DTR change through the changes in canopy evaporation and transpiration.

关键词： land use/land cover change diurnal temperature range climate change

在线全文

学校读者我要写书评

暂无评论

属性加权的朴素贝叶斯集成分类器

计算机工程与应用 2010年第29期46卷 144-146页

作者：张雯张化祥山东师范大学信息科学与工程学院济南250014

为提高朴素贝叶斯分类器的分类精度和泛化能力,提出了基于属性相关性的加权贝叶斯集成方法(WEBNC)。根据每个条件属性与决策属性的相关度对其赋以相应的权值,然后用AdaBoost训练属性加权后的BNC。该分类方法在16个UCI标准数据集上进行... 详细信息

为提高朴素贝叶斯分类器的分类精度和泛化能力,提出了基于属性相关性的加权贝叶斯集成方法(WEBNC)。根据每个条件属性与决策属性的相关度对其赋以相应的权值,然后用AdaBoost训练属性加权后的BNC。该分类方法在16个UCI标准数据集上进行了测试,并与BNC、贝叶斯网和由AdaBoost训练出的BNC进行比较,实验结果表明,该分类器具有更高的分类精度与泛化能力。

关键词：朴素贝叶斯分类器相关度相关系数属性加权 AdaBoost

南京市大气细颗粒物(PM_(2.5))中硝基多环芳烃污染特征与风险评估

在线全文

学校读者我要写书评

暂无评论

环境科学 2021年第6期42卷 2626-2633页

作者：傅银银文浩哲王向华于南洋李冰韦斯南京大学环境学院污染控制与资源化研究国家重点实验室南京210023 江苏环保产业技术研究院南京210019

硝基多环芳烃是大气细颗粒物中具有致癌效应的一类重要污染物,为探明硝基多环芳烃污染特征与来源,采集南京市14个大气细颗粒样品,利用气相色谱-质谱联用仪(GC-MS)测定硝基多环芳烃浓度,进行分布特征分析,来源识别和健康风险评估.结果表... 详细信息

硝基多环芳烃是大气细颗粒物中具有致癌效应的一类重要污染物,为探明硝基多环芳烃污染特征与来源,采集南京市14个大气细颗粒样品,利用气相色谱-质谱联用仪(GC-MS)测定硝基多环芳烃浓度,进行分布特征分析,来源识别和健康风险评估.结果表明,南京市大气细颗粒物中2,8-二硝基二苯并噻吩(743 pg·m^(-3))、2,7-二硝基芴(331 pg·m^(-3))、9-硝基蒽(326pg·m^(-3))、3-硝基荧蒽(217 pg·m^(-3))和1,8-二硝基芘(193 pg·m^(-3))为主要的硝基多环芳烃;硝基多环芳烃检出浓度具有明显的季节变化,冬季最高(3082 pg·m^(-3)),秋季其次(1553 pg·m^(-3)),春季最低(1218 pg·m^(-3)).南京市大气细颗粒物中硝基多环芳烃主要来自多环芳烃大气光氧化反应与生物质燃烧,二次生成是硝基多环芳烃的重要来源.当前南京PM_(2.5)中硝基多环芳烃的致癌风险可控,二硝基多环芳烃是致癌风险的主要来源.

关键词： 1 8-二硝基芘(1 8N-Pyr) 9-硝基蒽(9N-Ant) 3-硝基荧蒽(3N-Flt) 二次颗粒物生物质燃烧致癌风险

Effects of Sb Addition on Microstructural Evolution and Mechanical Properties of Mg–9Al–5Sn Alloy

在线全文

学校读者我要写书评

暂无评论

Acta Metallurgica Sinica(English Letters) 2021年第2期34卷 278-288页

作者： Chun-hua Ma Fu-Sheng Pan Ding-Fei Zhang Ai-Tao Tang Zhi-wen Lu College of Materials Science and Engineering Chongqing UniversityChongqing 400045China College of Mechanical and Electronic Engineering Nanyang Normal UniversityNanyang 473061China

The Mg–9Al–5Sn-xSb(x=0.0,0.3,0.6,1.0,1.5 wt%)alloys were prepared by a simple alloying process followed by hot extrusion with an extrusion ratio of *** effects of Sb additions on the microstructure and mechanical properties of the Mg–9 Al–5 Sn alloys were investigated by optical microscopy,X-ray diffraction,transmission electron microscopy,scanning electron microscopy equipped with an energy-dispersive X-ray *** results indicated that the phasesα-Mg matrix,Mg2Sn,Mg_(3)Sb_(2) and Mg17 Al12 exist in the as-cast Sb-containing *** addition results in the precipitation of Mg_(3)Sb_(2).The dendritic size of these alloys decreases with the addition of *** their ultimate tensile strength and yield strength of extruded alloys increase,and their elongation decreases gradually with increasing the content of *** better mechanical properties of the as-extruded alloys were achieved due to the refined grains and the formation of dispersive second phases Mg_(3)Sb_(2).

关键词： Mg–Al–Sn–Sb alloy Microstructure Extrusion Second phase Mechanical properties

Highly linear polyethylenes using the2-(1-(2,4-dibenzhydrylnaphthylimino)ethyl)-6-(1-(arylimino)ethyl)-pyridylcobalt chlorides: synthesis, characterization and ethylene polymerization

在线全文

学校读者我要写书评

暂无评论

Science China Chemistry 2016年第10期59卷 1291-1300页

作者： Erlin Yue Yanning Zeng wenjuan Zhang Yang Sun Xiao-Ping Cao wen-hua Sun CAS Key Laboratory of Engineering Plastics Beijing National Laboratory for Molecular Sciences Institute of ChemistryChinese Academy of Sciences State Key Laboratory of Applied Organic Chemistry College of Chemistry and Chemical Engineering Lanzhou University

The series of 2-（1-（2,4-dibenzhydrylnaphthylimino）ethyl）-6-（1-（arylimino）ethyl）pyridine derivatives and their cobalt chlorides （Col-Co5） were synthesized and fully characterized. The representative complexes Co2 and Co3 were confirmed by single crystal X-ray diffraction analyses, indicating pseudo-square-pyramidal geometry around the cobalt centre. All cobalt complexes, activated with either methylaluminoxane （MAO） or modified methylaluminoxane （MMAO）, exhibited high activities towards ethylene polymerization, and produced polyethylenes with high molecular weight and highly linear feature as well as unimodal distribution.

关键词： cobalt complexes ethylene polymerization highly linear polyethylene unimodal distribution

在线全文

学校读者我要写书评

暂无评论

一种新型结构微波介质滤波器的设计及仿真

压电与声光 2007年第1期29卷 23-25页

作者：梁飞吕文中周东祥朱建华华中科技大学电子科学和技术系湖北武汉430074

详细论述了一种新型结构微波介质滤波器的设计方法,分析了滤波器结构中耦合结构与谐振结构的相互影响关系,根据微波网络理论计算出的微波介质滤波器结构参数值,并采用高频结构模拟软件(HFSS)对滤波器结构进行仿真优化,得到了性能满足要... 详细信息

详细论述了一种新型结构微波介质滤波器的设计方法,分析了滤波器结构中耦合结构与谐振结构的相互影响关系,根据微波网络理论计算出的微波介质滤波器结构参数值,并采用高频结构模拟软件(HFSS)对滤波器结构进行仿真优化,得到了性能满足要求的仿真结果,根据仿真优化的结果制备出的微波介质滤波器其性能与设计要求相吻合。

关键词：微波介质滤波器设计仿真 HFSS(高频结构模拟软件)

E-selectin and its ligand-sLeX in the metastasis of hepatocellular carcinoma

在线全文

学校读者我要写书评

暂无评论

Hepatobiliary & Pancreatic Diseases International 2002年第1期1卷 80-82页

作者： Bao-hua Zhang han Chen Xiao-Ping Yao wen-ming Cong Meng-Chao Wu From the Eastern Hepatobiliary Surgery Hospital, Second Military Medical University of PLA, Shanghai 200438, China Eastern Hepatobiliary Surgery Hospital Second Military Medical University of PLA Shanghai 200438 China. zhbh_1@***

Objective: To study the significance of E-selectin andits ligand-sLeX in the metastasis of hepatocellularcarcinoma (HCC).Methods: Flow cytometry and immunohistochemistrywere used to detect the expression of E-selectin and itsligand-sLeX in both HCC cell lines and human ***: The positive rate of E-selectin in vascular en-dothelial cells adjacent to cancer was 67.9% (19/28). Theexpression of E-selectin in tumors accompanied withemboli or satellite foci was significantly higher than thatin tumors without emboli or satellite foci (Phan in primary ***: E-selectin and its ligand-sLeX are closelycorrelated with the metastasis of HCC.

关键词： liver neoplasm E-selectin sLeX metastasis

Effects of plication procedures in special cases of Peyronie’s disease:a single-center retrospective study of 72 patients

在线全文

学校读者我要写书评

暂无评论

Asian Journal of Andrology 2022年第3期24卷 294-298页

作者： wen Ji Li Jie-wen Bao Jian-hua Guo Da-Chao Zheng Min-Kai Xie Zhong Wang Department of Urology and Andrology Ninth People’s HospitalSchool of MedicineShanghai Jiaotong UniversityShanghai 200011China

General recommendations regarding surgical techniques are not always appropriate for all Peyronie’s disease(PD)***,the purpose of this study was to investigate the effects of plication procedures in PD patients with severe penile curvature and the effects of early surgical correction in patients who no longer have progressive *** clinical data from 72 patients who underwent plication procedures were analyzed in this *** were divided into Groups A and B according to the curvature severity(≤60°or>60°)and Groups 1 and 2 according to the duration of disease stabilization(≥3 months orhan that in Group 2(mean±standard deviation[s.d.]:20.9±2.0 months and 14.3±1.2 months,respectively,P<0.001).The present study showed that the plication procedures seemed to be an effective choice for the surgical treatment of PD patients with severe penile *** addition,the early surgical treatment seemed to benefit those patients who already had no erectile pain and no longer exhibited progressive deformity.

关键词： penile curvature Peyronie’s disease plication

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

生物炭表面NO吸附特性的量子化学研究

原子与分子物理学报 2025年第5期42卷 13-22页

作者：朱世遥薛婕雯张雨轩陈斌武卫东上海理工大学上海工程技术大学城市轨道交通学院上海交通大学机械与动力工程学院

生物炭表面具有丰富的官能团，通过化学吸附可以与一氧化氮（NO）分子形成稳定化学键，廉价易得且环境适应性强，具有广阔的应用前景.然而，当前对生物炭表面NO吸附特性的研究大多仍停留在宏观层面，缺乏深入的微观机制解析.本文基于密... 详细信息

生物炭表面具有丰富的官能团，通过化学吸附可以与一氧化氮（NO）分子形成稳定化学键，廉价易得且环境适应性强，具有广阔的应用前景.然而，当前对生物炭表面NO吸附特性的研究大多仍停留在宏观层面，缺乏深入的微观机制解析.本文基于密度泛函理论，深入研究了生物炭表面一氧化氮（NO）的吸附转化路径，从分子层面揭示了生物炭对NO的吸附特性.研究结果显示，N-down型吸附构型的能量普遍低于O-down型吸附构型，是较为可能的吸附构型，并且含氧原子的官能团在NO的吸附和氨（NH3）的形成过程中扮演着关键角色.此外，通过对N-down型构型的进一步分析发现，在与活性位点结合后，NO将优先取代羟基，最终在生物质焦炭表面转化为NH3.同时，基于变分过渡态理论（CVT）计算了反应速率，发现NO优先反应的途径将受到不同区域内反应速率的限制.本文通过量子化学方法深入揭示了生物炭表面NO吸附特性的微观机制，为优化生物炭在NO治理中的应用提供了理论支持.

关键词：吸附生物炭密度泛函理论