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相图热力学数据库及其计算软件:过去、现在和将来
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作者 刘树红 金波 +4 位作者 傅太白 曾银平 都昌发 杜勇 郑洲顺 《中国科学:化学》 CAS CSCD 北大核心 2019年第7期966-977,共12页
相图热力学信息是材料设计和研发的重要基础之一。基于热力学数据库的CALPHAD (CALculation of PHAse Diagram)方法使得多元多相材料的相图热力学计算成为可能。随着材料基因组工程(Materials Genome Initiative, MGI)和集成计算材料工... 相图热力学信息是材料设计和研发的重要基础之一。基于热力学数据库的CALPHAD (CALculation of PHAse Diagram)方法使得多元多相材料的相图热力学计算成为可能。随着材料基因组工程(Materials Genome Initiative, MGI)和集成计算材料工程(Integrated Computational Material Engineering, ICME)的发展,各种材料的热力学数据库及计算软件不断涌现。本文结合本课题组在该方向的研究工作对相图热力学数据库及其计算软件的过去进行了简单回顾,并对现状以及未来的发展趋势进行了讨论。 展开更多
关键词 相图热力学数据库 计算软件 CALPHAD方法 材料基因组工程
三维激光雷达技术在高压输电线路巡维中的应用评述 预览
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作者 秦川 杜勇 +1 位作者 王奇 沈小军 《遥感科学:中英文版》 2018年第1期1-8,共8页
随着三维激光雷达技术的不断进步,因其具有高效率、高精度、非接触、实时性等多种优势,已被逐步应用于高压输电线路巡维领域,但由于相关研究尚处于起步阶段,仍存在着标准不统一、应用方式少等诸多问题。本文首先简要叙述了机载和地面三... 随着三维激光雷达技术的不断进步,因其具有高效率、高精度、非接触、实时性等多种优势,已被逐步应用于高压输电线路巡维领域,但由于相关研究尚处于起步阶段,仍存在着标准不统一、应用方式少等诸多问题。本文首先简要叙述了机载和地面三维激光雷达的工作原理,然后回顾了三维激光雷达技术在架空线路巡维中已验证的主要应用功能,指出了三维激光雷达技术在高压输电线路巡维中具有重要的工程应用价值,最后结合三维激光雷达在架空线路应用中存在的问题,指出应从新功能开发、应用方法的标准化、数据处理的通用性和简便性等方面开展深化研究。 展开更多
关键词 高压输电线路 机载激光雷达 地面激光雷达 巡维应用 现状与展望
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Texture/Microstructural Evolution and Mechanical Properties of a Hot and Cold Rolled Al-Mg-Si-Cu Alloy 预览
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作者 Yihan Wang Lixin Zhang +4 位作者 Xiaohui Yang Kai Li Song Ni Yong Du Min Song 《矿物质和材料特性和工程(英文)》 2017年第4期209-222,共14页
The evolutions of texture, microstructure as well as mechanical properties of an Al-Mg-Si-Cu alloy during hot and cold rolling were investigated by TEM, EBSD and X-ray diffraction in this study. The results revealed t... The evolutions of texture, microstructure as well as mechanical properties of an Al-Mg-Si-Cu alloy during hot and cold rolling were investigated by TEM, EBSD and X-ray diffraction in this study. The results revealed that formation of sub-grain boundaries and //RD fiber texture after hot rolling is beneficial to the increase of the elongation of the alloy. The shear texture of //RD fiber and γ-fiber occupies a dominant role during the hot rolling process, while the main texture during the cold rolling process is the rolling texture of β-fiber. β-fiber and τ-fiber texture components are identified as two main types of texture components during cold rolling, and the Brass component {011} is transformed into Goss component {011} with the increase of the deformation. 展开更多
关键词 EBSD MICROSTRUCTURE TEXTURE Evolution MECHANICAL Properties ODFs
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Computed tomography-guided catheter drainage with urokinase and ozone in management of empyema 预览
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作者 Bing Li Chuan Liu +5 位作者 Yang Li Han-Feng Yang Yong Du Chuan Zhang Hou-Jun Zheng Xiao-Xue Xu 《世界放射学杂志:英文版(电子版)》 2017年第4期212-216,共5页
AIM To retrospectively compare the outcomes of catheter drainage,urokinase and ozone in management of empyema.METHODS Retrospective study included 209 patients(111 males and 98 females; age range 19 to 72 years) who w... AIM To retrospectively compare the outcomes of catheter drainage,urokinase and ozone in management of empyema.METHODS Retrospective study included 209 patients(111 males and 98 females; age range 19 to 72 years) who were diagnosed with empyema.The patients were divided into 3 groups based on the therapy instituted: catheter drainage only(group I); catheter drainage and urokinase(group II); catheter drainage,urokinase and ozone(group III).Drainage was considered successful if empyema was resolved with closure of cavity,clinical symptoms were resolved,and need for any further surgical procedure was avoided.Success rate,length of stay(LOS),need for further surgery and hospital costs were compared between the three groups using the Kruskall-Wallis nonparametric test,with P < 0.05 considered significant.RESULTS Of the 209 patients with empyema,all catheters were placed successfully under CT guidance.Sixty-three patients were treated with catheters alone(group I),64 with catheters and urokinase(group II),and 82 with catheters,urokinase and ozone(group III).Group I,group II and group III had success rates of 62%,83% and 95% respectively(P < 0.05).Group I and groupII had statistically longer LOS(P < 0.05) and higher hospital costs(P < 0.05) compared to group III.There were statistically significant differences between the three groups when comparing patients who converted into further surgery.CONCLUSION The combination of chest tube drainage,urokinase and ozone is a safe and effective therapeutic modality in thoracic empyema. 展开更多
关键词 计算指导断层摄影术 导管排水 尿激 臭氧 蓄脓症
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Vertical Integration and Reverse Engineering of Agricultural Enterprises 预览
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作者 Gang WU Yong DU 《亚洲农业研究:英文版》 2014年第2期5-8,共4页
This paper studies the potential effects of agricultural enterprise’s vertical integration and reverse engineering on downstream firms.Suppliers who invest reverse engineering technology can exploit customer’s infor... This paper studies the potential effects of agricultural enterprise’s vertical integration and reverse engineering on downstream firms.Suppliers who invest reverse engineering technology can exploit customer’s information. An integrated supplier can obtain at no cost the information from its subsidiary. Based on repeated game and considered corporate " good" or " bad" type,this paper analysis supplier’s selection and downstream investment in innovation. The results showed that: when the cost is higher than the threshold value no company invest in reverse engineering,when the cost is lower than the threshold value the integration company invest in reverse engineering; in the second period,vertical integration reduce the downstream independent enterprise’s innovation investment and profits,integrated enterprise increase innovation investment and profits; during the first period of the game,the independent downstream firms being " completely foreclosure". 展开更多
关键词 AGRICULTURAL INTEGRATION VERTICAL INTEGRATION MARK
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Study on the Agricultural Biotechnology Innovation Based on the Product Differentiation 预览
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作者 Gang WU Yong DU 《亚洲农业研究:英文版》 2014年第5期18-21,共4页
Based on product differentiation,this paper researches the innovation of agricultural biotechnology. In the duopoly structure,the company’s investment in innovation is affected by the product differentiation,and the ... Based on product differentiation,this paper researches the innovation of agricultural biotechnology. In the duopoly structure,the company’s investment in innovation is affected by the product differentiation,and the greater the difference,the greater the willingness to increase investment and improve quality; at the same time,low innovative cost companies will choose a higher level of investment in innovation and quality. If there is no difference between the products,the companies with high cost of innovation abandon quality competition,and the companies with low cost of innovation " monopolize" the market. 展开更多
关键词 AGRICULTURAL BIOTECHNOLOGY PRODUCT DIFFERENTIATION
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Al-Fe-Si、Al-Mn-Si与Al-Fe-Mn-Si体系热力学描述的更新 预览
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作者 陈海林 陈清 +2 位作者 杜勇 Johan BRATBERG Anders ENGSTROM 《中国有色金属学报:英文版》 SCIE EI CAS CSCD 2014年第7期2041-2053,共13页
采用Calphad方法对Al-Fe-Mn-Si四元系及其子体系进行热力学评估。首先,通过考虑文献中最新的实验研究结果以及对部分三元化合物应用新的热力学模型,修正Al-Fe-Si三系的热力学描述,显著地改善了整个成分范围内、尤其是富Al角的液相面... 采用Calphad方法对Al-Fe-Mn-Si四元系及其子体系进行热力学评估。首先,通过考虑文献中最新的实验研究结果以及对部分三元化合物应用新的热力学模型,修正Al-Fe-Si三系的热力学描述,显著地改善了整个成分范围内、尤其是富Al角的液相面投影图。随后,对三元化合物a-AlMnSi和β-AlMnSi采用新的模型,精修Al-Mn-Si体系富Al角的热力学描述。然后,通过模拟a-AlMnSi相在Al-Fe-Mn-Si体系中的固溶度,优化Al-Fe-Mn-Si四元系富Al角的热力学描述。在优化时,对a-AlMnSi作特殊考虑并加入限制条件,以确保其不会在Al-Fe-Si三元系中变得稳定。最后,将所获得的热力学描述加入TCAL数据库,通过一系列的相平衡计算与凝固模拟、以及与商业铝合金的实验数据的比较,对所获得的热力学描述进行全面的验证。更新后的TCAL数据库能够可靠地预测Al-Fe-Si基与Al-Fe-Mn-Si基合金中的相形成。 展开更多
关键词 Al-Fe-Si Al-Fe-Mn-Si 铝合金 热力学模拟 凝固
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Study on the Reasons and Countermeasures for Loss of Listed Companies in Manufacturing Industry 预览
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作者 Yong DU Jun DU Bo YAN 《亚洲农业研究:英文版》 2013年第12期21-24,29共5页
In combination with the data of loss-making listed companies in manufacturing industry at capital market in 2008-2010,this paper analyzed the characteristics of loss of listed companies.Major reasons include the blind... In combination with the data of loss-making listed companies in manufacturing industry at capital market in 2008-2010,this paper analyzed the characteristics of loss of listed companies.Major reasons include the blind investment of management personnel,low operation and management level,blind pursuit of diversified operation,improper stock right structure,weak supervision of government,and imperfect delisting system.Finally,it came up with some countermeasures,including improving quality of management personnel,management personnel selecting proper investment projects,strengthening internal management of enterprise,implementing effective asset rearrangement,setting up effective incentive and restrictive mechanism,bringing into play regulation function of banks,improving delisting mechanism,reducing centralization of state owned stock right,and establishing and improving market information disclosure system. 展开更多
关键词 Manufacturing industry LISTED COMPANIES LOSS Reaso
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胸的硬膜上的 angiolipoma : 一份案例报告和文学的评论 预览
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作者 Jun Meng Yong Du +4 位作者 Han-Feng Yang Fu-Bi Hu Ya-Yong Huang Bing Li Chi-Shing Zee 《世界放射学杂志:英文版(电子版)》 2013年第4期187-192,共6页
Angiolipoma of the spine is a benign neoplasm consisting of both mature fatty tissue and abnormal vascular elements, and usually presents with a slow progressive clinical course. Our patient presented with bilateral ... Angiolipoma of the spine is a benign neoplasm consisting of both mature fatty tissue and abnormal vascular elements, and usually presents with a slow progressive clinical course. Our patient presented with bilateral lower extremity weakness and chest-back numbness. Physical examination revealed adipose elements superficial hypesthesia below the T5 level and analgesia below the T6 level. Magnetic resonance imaging (MRI) scan showed an avidly and heterogeneously enhancing mass which was located in the posterior epidural space. Compression of the thoracic cord by the fusiform mass was seen between T3-T4. During the operation, a flesh pink vascular mass (4.7 cm × 1.0 cm × 1.0 cm) with obscure margin and strong but pliable texture was found in the posterior epidural space extending from T3 to T4. There was no infiltration of the dura or the adjacent bony spine. Histopathological study of the surgical specimen showed a typical angiolipoma. We review the previously documented cases of spinal extradural angiolipomas performed with MRI. 展开更多
关键词 ANGIOLIPOMA SPINAL EPIDURAL tumor SPINAL CORD compression HISTOPATHOLOGY
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Study on the antiulcer effects of Veronicastrum axillare on gastric ulcer in rats induced by ethanol based on tumor necrosis factor-α(TNF-α)and endothelin-1(ET-1) 被引量:4
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作者 Yong Du Weichun Zhao +4 位作者 Leilei Lu Jiayan Zheng Xishi Hu Zhehan Yu Lixin Zhu 《亚太热带生物医学杂志:英文版》 2013年第12期925-930,共6页
Objective:To assess whether Veronicastrum axillare(V.axillare)can ameliorate ethanol-induced gastric mucosal lesions in rats,reduce the production of pro-inflammatory cytokines,suppress apoptosis and improve local mi... Objective:To assess whether Veronicastrum axillare(V.axillare)can ameliorate ethanol-induced gastric mucosal lesions in rats,reduce the production of pro-inflammatory cytokines,suppress apoptosis and improve local microcirculation disturbances.Methods:Totally 48 male Sprague-Dawley rats were randomly divided into six groups,eight rats in each group.Rats in the normal group and the model group were administered with 0.9%normal saline respectively.Rats in the positive group and ranitidine group were administered with 0.18%ranitidine suspension by intragastric administration respectively.Those in the high dose V.axillare group,the medium dose V.axillare group and the low dose V.axillare group were administrated with V.axillare at the daily dose of 2.8 g/kg,1.4 g/kg and 0.7 g/kg by intragastric administration.Gastric mucosal lesions were produced by intragastric administration of absolute ethanol.Water extract of V.axillare was successively injected for 14 d and last day was injected 1 h before ethanol administration.Gastric mucosal ulcer index and ulcer inhibitory rate were counted by improved Guth methods.The tissue sections were made for pathological histology analysis.Also,we measured the concentrations of tumor necrosis factor-α(TNF-α)and endothelin-1(ET-1)in gastric mucosal,as an index of the pro-inflammatory cytokines,apoptosis and local microcirculation.Besides,the mRNA contents of TNF-αand ET-1 were measured to verify effects on gene expression by real-time fluorescent quantitative PCR.Results:Water extract of V.axillare significantly ameliorated the gastric mucosal lesions induced by ethanol administration(P【0.01).Pro-inflammatory cytokines,TNF-a and ET-1 were increased after ethanol administration and significantly reduced by water extract of V.axillare.The expressions of TNF-αand ET-1 mRNA were also be inhibited by water extract of V.axillare.Conclusion:Current evidences show water extract of V.axillare is effective for defending against ethanol-induced gastric mucosal lesions,significantly inhibi 展开更多
关键词 Veronicastrum axillare(Sieb.et Zucc) Yamazaki Gastric mucosal lesions PRO-INFLAMMATORY cytokines TNF-Α ET-1
液相扩散系数对Al356.1合金凝固过程显微组织演变的影响 预览 被引量:1
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作者 孙伟华 张利军 +2 位作者 魏明 杜勇 黄伯云 《中国有色金属学报:英文版》 SCIE EI CAS CSCD 2013年第12期3722-3728,共7页
采用相场方法研究了液相扩散系数对 Al356.1合金凝固过程初晶(Al)相显微组织演变的影响。在相场模拟中,采用了两套液相扩散系数,而其他热物理参数和数值参数则保持一致。第一套液相扩散系数只考虑随温度变化的 Arrhenius 类型的杂... 采用相场方法研究了液相扩散系数对 Al356.1合金凝固过程初晶(Al)相显微组织演变的影响。在相场模拟中,采用了两套液相扩散系数,而其他热物理参数和数值参数则保持一致。第一套液相扩散系数只考虑随温度变化的 Arrhenius 类型的杂质扩散系数,而第二套则为随温度和成分变化的精准的液相原子移动性数据库。对于第二套液相扩散系数,还分析了扩散系数矩阵中的非对角项对Al356.1合金凝固过程中显微组织演变的影响。通过相场模拟发现:在3种液相扩散系数情况下,初晶(Al)相的形貌、枝晶尖端的速率和枝晶前端的成分曲线均有不同。研究结果表明:精确的液相原子移动性参数对定量模拟凝固过程显微组织演变是非常重要的。 展开更多
关键词 Al356 1合金 凝固 显微组织演变 扩散系数 相场模拟
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Atomic mobilities and diffusivities in Al alloys 被引量:1
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作者 DU Yong ZHANG LiJun +5 位作者 CUI SenLin ZHAO DongDong LIU DanDan ZHANG WeiBin SUN WeiHua JIE WanQi 《中国科学:技术科学英文版》 SCIE EI CAS 2012年第2期 306-328,共23页
扩散性的知识是为理解许多科学、工艺的学科的一个前提。在这份报纸,第一主要的试验性的方法,被采用提供各种各样的扩散性数据,简短被描述。第二,包括第一原则的方法,各种各样的计算方法的基础嵌入原子 method/molecular 动态模拟... 扩散性的知识是为理解许多科学、工艺的学科的一个前提。在这份报纸,第一主要的试验性的方法,被采用提供各种各样的扩散性数据,简短被描述。第二,包括第一原则的方法,各种各样的计算方法的基础嵌入原子 method/molecular 动态模拟,半实验的途径,和现象学的 DICTRA 技术,被表明。最近为顺序 / 混乱转变和 stoichiometric 混合物开发的散开模型简短也被描绘。第三,为在 multicomponent 艾尔合金的液体, fcc_A1, L12, bcc_A2, bcc_B2,和金属间化合的阶段的一个最新确定的扩散性数据库在二进制、第三、第四级的系统经由一些案例研究被介绍。并且各种各样的计算技术和试验性的方法的集成被加亮。这个扩散性数据库的可靠性被在各种各样的二进制、第三、第四级的散开夫妇比较计算、测量的集中侧面,散开路径,和 Kirkendall 移动验证。下次,确定的扩散性数据库与一起热力学并且另外的 thermo 物理的性质被利用在团结, interdiffusion 和降水期间为艾尔合金模仿微结构进化。特殊讨论在夫妇们创作了的一系列 Ni-Al 散开在 interdiffusion 微观结构的阶段地模拟上被介绍,,并且在协调紧张和外部压缩力量的效果下面的阶段。在扩散性数据库的下一代的建立的未来取向最后被探讨。 展开更多
关键词 扩散模型 AL合金 原子 数据库建立 半经验方法 迁移 第一原理方法 计算技术
多重枕骨的缺点由蛛网状的使成粒状引起了: 印射的 T2 上的强调 预览
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作者 Chao-Xuan Lu, Yong Du, Xiao-Xue Xu, Yang Li, Han-Feng Yang, Shao-Qiang Deng, Dong-Mei Xiao, Bing Li Yun-Hong Tian 《世界放射学杂志:英文版(电子版)》 2012年第7期341-344,共4页
A 56-year-old man presented with a 6-mo history of headache. Although neurological and laboratory examinations were normal, computed tomography (CT) scan was performed which revealed multiple occipital osteolytic les... A 56-year-old man presented with a 6-mo history of headache. Although neurological and laboratory examinations were normal, computed tomography (CT) scan was performed which revealed multiple occipital osteolytic lesions, which were suspected to be multiple myeloma. Subsequently nuclear magnetic resonance imaging (MRI) showed that these lesions presented with a cerebrospinal fluid (CSF)-like signal intensity, no diffusional restriction and intrinsic mass-like enhancement on conventional sequences were seen. T2 relaxation time was similar to that of CSF in the ventricles and adjacent subarachnoid space on T2-mapping. Single photon emission CT with 99m Tc-Methyl diphosphonate was performed which revealed no increased radiotracing accumulation. Finally, these lesions were diagnosed as mutiple arachnoid granulations (AGs). The headache was treated symptomatically with medical therapy. On follow up examination after 6 mo no evidence of tumor was detected. This report aimed to illustrate the appearance and differentiation of occipital defects caused by multiple AGs on CT and MRI, with emphasis on the findings from T2 mapping. 展开更多
关键词 ARACHNOID GRANULATION OCCIPITAL DEFECT Magnetic resonance imaging COMPUTED tomography T2mapping
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Alternative Methylation for the Synthesis of (+)-Perophoramidine
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作者 杜宇 吴昊星 +2 位作者 宋颢 秦勇 张丹 《中国化学:英文版》 SCIE CAS CSCD 2012年第9期1970-1973,共4页
关键词 甲基化 全合成 一步氧化 异构化反应 酸催化 MNO
Recent progress in criterions for glass forming ability 预览 被引量:1
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作者 杨兵 杜勇 刘咏 《中国有色金属学会会刊:英文版》 EI CSCD 2009年第1期 78-84,共7页
形成眼镜的能力(GFA ) 是在学习金属性的眼镜的一个重要因素。到目前为止,为评估形成眼镜的能力有几个标准。为为体积预言作文然而,他们差不多显示出的金属性的眼镜为不同盒子的精确性和通用性。在这个工作,为形成眼镜的能力的标准... 形成眼镜的能力(GFA ) 是在学习金属性的眼镜的一个重要因素。到目前为止,为评估形成眼镜的能力有几个标准。为为体积预言作文然而,他们差不多显示出的金属性的眼镜为不同盒子的精确性和通用性。在这个工作,为形成眼镜的能力的标准的四种类型被分类并且考察:1 ) 有典型温度的指示物;2 ) 包含结构的因素的指示物;3 ) 指示物基于 Miedema 的模型;并且 4 ) 原告基于阶段图。单个指示物不能被用来由于它的有限理论框架正确地预言所有金属性的玻璃系统的 GFA,这被指出,并且多重指示物的联合显示出更多的效率和精确性。尽管为 GFA 开发通用指示物仍然是很困难的,最近的指示物似乎比以前建议的那些具有更可靠的物理意思。 展开更多
关键词 金属玻璃 金属学 动力学 物理学
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性别和年龄对中国人冠状动脉旁路移植术后住院病死率的影响 被引量:5
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作者 宫路佳 Elke Lehmkuhl +10 位作者 胡盛寿 Friederike Kendel Stein Kandle Yong Du 章晏 杜茗 吴清玉 许建屏 孙立忠 朱晓东 Vera Regitz-Zagrosek 《中华心血管病杂志》 CAS CSCD 北大核心 2006年第5期 415-421,共7页
目的确定中国人冠状动脉旁路移植术后住院病死率是否存在性别差异以及该差异是否与年龄相关.方法回顾性分析1997年1月1日至2001年12月31日阜外心血管病医院外科全部接受冠状动脉旁路移植术的患者共2682例(男性2316例,女性366例).按照... 目的确定中国人冠状动脉旁路移植术后住院病死率是否存在性别差异以及该差异是否与年龄相关.方法回顾性分析1997年1月1日至2001年12月31日阜外心血管病医院外科全部接受冠状动脉旁路移植术的患者共2682例(男性2316例,女性366例).按照性别和年龄分组调查它们之间的围手术期并发症及手术后住院病死率的差异.结果女性术前合并主要疾病的比例比男性高,术后并发症多,但她们术前的左心室射血分数较男性好,且冠状动脉病变数量少.然而,女性患者的术后住院病死率是男性的3倍(女性3.01%,男性1.12%,P=0.001),病死率的性别差异在低龄组更有统计学意义(女性2.6%,男性0.5%,P=0.001,ORs:4.844,95%可信区间:1.549~15.142),在老年患者中则无统计学意义(女性3.7%,男性2.4%,P=0.383).结论中国女性冠状动脉旁路移植术的住院病死率高于男性,特别是低龄女性.低龄组女性是住院病死率的独立危险因素.死亡率的性别差异随年龄增加而减少.需要进一步的研究来阐明病死率的性别差异在低龄组更显著的原因. 展开更多
关键词 冠状动脉分流术 性别 年龄 医院死亡率
大空间建筑火灾中火焰辐射对无保护钢构件升温的影响 预览 被引量:12
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作者 杜咏 李国强 《火灾科学》 CSCD 2006年第4期 189-199,共11页
大空间建筑的空间尺度变化范围较大,当空间尺度变化时火焰对壁面或构件的热辐射变化也较大,正确预测火焰辐射对构件升温的影响,是准确计算火灾场景中构件升温的一个重要环节。在计算假定条件下,通过分析外界与构件之间的热量交换以... 大空间建筑的空间尺度变化范围较大,当空间尺度变化时火焰对壁面或构件的热辐射变化也较大,正确预测火焰辐射对构件升温的影响,是准确计算火灾场景中构件升温的一个重要环节。在计算假定条件下,通过分析外界与构件之间的热量交换以及影响火焰辐射的因素,导出考虑火焰辐射影响的构件净吸热量计算公式,将构件净吸热量计算公式导入基于集总热容法的热平衡方程中,得到构件升温的数值解,从而定量确定火焰辐射对钢构件升温影响的,临界角系数,为简化钢构件升温计算奠定基础,使钢构件升温计算既准确反映火灾中构件的升温历程,又方便实用。 展开更多
关键词 辐射传热 火焰辐射 大空间建筑火灾
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Understanding of hydrogen desorption mechanism from defect point of view
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《国家科学评论:英文版》 CSCD 2018年第3期318-320,共3页
辛轨形群胚的辛邻域定理
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作者 杜承勇 陈柏辉 王蕊 《数学学报》 CSCD 北大核心 2018年第2期217-232,共16页
本文给出一种几何的子轨形群胚的定义,还给出了判定子轨形群胚的依据,并证明了紧子轨形群胚的轨形管状邻域、紧辛子轨形群胚的辛邻域和紧Lagrangian子轨形群胚的Lagrangian邻域的存在性.
关键词 子轨形群胚 轨形管状邻域 辛子轨形群胚 辛邻域 Lagrangian邻域
基于“可控”表界面工程的聚合物纳滤膜
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作者 吕嫣 杜勇 +2 位作者 杨尚锦 吴健 徐志康 《高分子学报》 CSCD 北大核心 2017年第12期1905-1914,共10页
复合纳滤膜凭借其效率高与能耗低的特点在分离膜领域占据着越来越重要的地位. 但其制备所面临的最大挑战在于如何实现选择性皮层构建过程及结构性能的有效调控.通过“可控”的表界面工程可以实现对界面性质及界面反应速率的调控,从而实... 复合纳滤膜凭借其效率高与能耗低的特点在分离膜领域占据着越来越重要的地位. 但其制备所面临的最大挑战在于如何实现选择性皮层构建过程及结构性能的有效调控.通过“可控”的表界面工程可以实现对界面性质及界面反应速率的调控,从而实现复合纳滤膜的可控制备和性能提升.因此,我们提出通过““可控”聚合-界面沉积”构建选择性皮层以实现复合纳滤膜分离层的创新制备和多功能化、基于“基膜-单体溶液界面构建”调控界面聚合以获得更薄分离层和更优异的纳滤性能.本文总结和评述了基于“可控”表界面工程的聚合物纳滤膜的重要进展,分析了该领域的未来研究方向,旨在为高性能复合纳滤膜的可控制备提供系统的方法学及理论支持. 展开更多
关键词 纳滤膜 复合膜 表界面工程 共沉积 界面聚合
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