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The relative energies of polypeptide conformers predicted by linear scaling second-order M?ller-Plesset perturbation theory

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Science China Chemistry 2014年第10期57卷 1393-1398页

作者： GUO Yang li Wei YUAN DanDan li shuhua Key Laboratory of Mesoscopic Chemistry Ministry of Education School of Chemistry and Chemical Engineering Institute of Theoretical and Computational Chemistry Nanjing University

We describe an implementation of the cluster-in-molecule （CIM） resolution of the identity （RI） approximation second-order Moller-Plesset perturbation theory （CIM-RI-MP2）, with the purpose of extending RI-MP2 calculations to very large systems. For typical conformers of several large polypeptides, we calculated their conformational energy differences with the CIM-RI-MP2 and the generalized energy-based fragmentation MP2 （GEBF-MP2） methods, and compared these results with the density functional theory （DFT） results obtained with several popular functionals. Our calculations show that the conformational energy differences obtained with CIM-RI-MP2 and GEBF-MP2 are very close to each other. In comparison with the GEBF-MP2 and CIM-RI-MP2 relative energies, we found that the DFT functionals （CAM-B3LYP-D3, LC-ωPBE-D3, M05-2X, M06-2X and coB97XD） can give quite accurate conformational energy differences for structurally similar conformers, but provide less-accurate results for structurally very different conformers.

关键词： cluster-in-molecule generalized energy-based fragmentation second-order Moller-Plesset perturbation theory resolution of the identity relative energy

Natural Philosophy of Zhouyiand life Practice

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Frontiers of Philosophy in China 2012年第2期7卷 179-190页

作者： li shuhua Department of Philosophy Nanjing UniversityNanjing 210093China

The natural philosophy which is implied in Zhouyi is a philosophy of generation. This is a metaphor for life and the unity of cosmology, ontology and axiology, based on a practice of life which is a unity of moral and cognitive practice. This article suggests that, based on the implications of the original classic text of Zhouyi and its commentaries, the characteristics and meaning of Chinese natural philosophy can be understood through the cosmology of morality, the ontology of unity of heaven, earth and humanity, the theory of practice that integrates knowing with action, and the methodology of wholly generating. I argue that this unique natural philosophy is not only the origin of the transcendental values of Chinese culture, but also the metaphysical foundation of ancient science in China. In the great transformation of history and dialogue between East and West in 21 st century, it creates a unity of different cultures of human beings from different ways which are harmonious but not uniform.

关键词： Dao virtue practice unity of heaven earth and human beings,integration of knowing with action wholly generating system of images andnumbers

盐酸纳布啡联合丙泊酚麻醉对无痛胃肠镜检查患者疼痛程度、血流动力学指标的影响

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药品评价 2024年第5期21卷 602-604页

作者：李淑华俞颖曾慧鹰潭市人民医院江西鹰潭335000

目的分析盐酸纳布啡复合丙泊酚麻醉对无痛胃肠镜检查患者的影响。方法选取2021年9月至2023年9月鹰潭市人民医院收治的96例无痛胃肠镜检查患者,按随机数字表法分为两组,各48例。对照组行丙泊酚麻醉,观察组行盐酸纳布啡复合丙泊酚麻醉。... 详细信息

目的分析盐酸纳布啡复合丙泊酚麻醉对无痛胃肠镜检查患者的影响。方法选取2021年9月至2023年9月鹰潭市人民医院收治的96例无痛胃肠镜检查患者,按随机数字表法分为两组,各48例。对照组行丙泊酚麻醉,观察组行盐酸纳布啡复合丙泊酚麻醉。对比两组麻醉相关指标、疼痛程度、血流动力学、不良反应。结果观察组自主呼吸恢复时间、睁眼时间、定向力恢复时间均短于对照组,丙泊酚用量少于对照组。观察组不良反应发生率6.25%低于对照组的20.83%。清醒5 min、30 min后,观察组VAS评分低于对照组(P0.05);麻醉后5 min、术毕时,观察组HR,MAP高于对照组(P<0.05)。结论盐酸纳布啡复合丙泊酚麻醉可减轻无痛胃肠镜患者疼痛,稳定血流动力学,促进苏醒,且不良反应更少。

关键词：无痛胃肠镜盐酸纳布啡丙泊酚不良反应

In-situ imaging of strain-induced enhancement of hydrogen evolution activity on the extruded MoO_(2)sheets

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Nano Research 2023年第4期16卷 5419-5426页

作者： Mansheng liao Qiaomei Zhu shuhua li Qiongqiong li Ziting Tao Yongchun Fu College of Chemistry and Chemical Engineering Hunan UniversityChangsha 410082China

Strain engineering is a useful strategy for modifying the catalytic activity of ***,in-situ visual characterization of the strain effect on the catalytic activity at nanoscale remains a huge ***,we performed in-situ electrochemical scanning tunneling microscopy(EC-STM)imaging measurements at the local strained regions of extruded singlecrystal molybdenum dioxide(MoO_(2))sheets with combination of current noise analysis(n-EC-STM).The intensity-enhanced noise was observed at the local strained region compared to the unstrained regions in the same frame,which reveals the positive effect of compressive strain on the hydrogen evolution reaction(HER)activity of MoO_(2)provided that the intensity of noise is positively correlated with catalytic HER Faradic ***,we clearly“see”the strain-induced enhancement of HER activity of MoO_(2)at nanoscale by means of noise *** work extends the visual characterization of strain engineering in electrocatalysis and related fields.

关键词： strain engineering visual characterization electrochemical scanning tunneling microscope noise enhancement

胸腺上皮性肿瘤CT特征与风险度及病理分型的相关性研究

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蚌埠医学院学报 2024年第9期49卷 1188-1194,1199页

作者：李淑华范晔李阳马宜传谢宗玉蚌埠医科大学第一附属医院放射科安徽蚌埠233004 蚌埠医科大学医学影像诊断学教研室安徽蚌埠233030 蚌埠医科大学临床医学院安徽蚌埠233030

目的:探讨胸腺上皮性肿瘤(TETs)CT影像特征与病理分型及风险分类的相关性。方法:回顾性分析经病理证实为TETs的术前临床及影像资料,比较TETs一般资料及CT特征与病理分型及风险分类的相关性,二元logisitic回归分析高风险TETs的独立危险因... 详细信息

目的:探讨胸腺上皮性肿瘤(TETs)CT影像特征与病理分型及风险分类的相关性。方法:回顾性分析经病理证实为TETs的术前临床及影像资料,比较TETs一般资料及CT特征与病理分型及风险分类的相关性,二元logisitic回归分析高风险TETs的独立危险因素,绘制预测TETs病人高风险的列线图,采用ROC曲线验证列线图模型的准确性。结果:年龄、胸痛、外缘、钙化、分隔、强化幅度、心包膜增厚、纵隔淋巴结转移、周围脂肪浸润在不同病理分型间存在差异(P<0.05)。胸痛、形态、外缘、密度、坏死/囊变、钙化、动脉期CT值、静脉期CT值、强化幅度、心包膜增厚、胸膜增厚、纵隔淋巴结转移、周围脂肪浸润、包绕纵隔结构及侵犯周围血管在低风险组及高风险组间差异有统计学意义(P<0.05)。胸痛、外缘及心包膜增厚是高风险TETs的独立危险因素,ROC分析列线图模型AUC为0.818(95%CI:0.712~0.897,P<0.01)。结论:结合临床及CT特征在一定程度上可预测TETs病理分型,由胸痛、外缘及心包膜增厚三个因素构建的列线图模型对TETs高风险病人的预测效能较好。

关键词：胸腺上皮性肿瘤体层摄影术 X线计算机病理学风险度列线图

The Impact of Global Warming on Russia's Ecological Environment

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Social Sciences in China 2021年第4期42卷 194-208页

作者： li shuhua Huang Deyuan Center for Russian Language literature and Culture Studies Heilongjiang University 不详

The Russian ecosystem is a complex consisting of the Arctic marine ecosystem,the tundra,forest,steppe,mountain and island ecosystems,as well as the terrestrial and water ecosystems,the spatial ecosystem,the atmospheric ecosystem,the soil ecosystem,*** than being independent,these ecosystems are *** warming,so destructive to the global ecosystem,particularly affects Russia due to the country’s unique geographical *** is a double-edged sword for the Russian ecosystem;it does have some beneficial effects,but on the whole,its negative consequences outweigh the *** negative effects are the decrease in the Arctic sea ice,the increase in carbon emissions,the lessening of biodiversity,an increase in forest pests and diseases,the spread of contagious diseases,the frequency of forest fires,changes in the habitat conditions of biological species,and environmental *** recent years,coping with these negative effects has become a major challenge for Russia’s sustainable ***,Russia is actively participating in international cooperation to deal with global warming and is optimizing the relevant domestic *** ensure the stable and balanced development of society and the economy,Russia has been striving to reduce Russian greenhouse gas emissions by 30 percent by 2030 compared to 1990,in order to further improve the country’s ecosystems.

关键词： forest ecosystems Ecological

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基于轻量化的铸铝发动机罩生命周期评价

合肥工业大学学报（自然科学版） 2024年第7期47卷 900-905页

作者：李书华贝璟吴钇陶汪永嘉张代胜合肥工业大学汽车与交通工程学院安徽合肥230009 合肥工业大学智能制造技术研究院安徽合肥230051

为实现汽车轻量化,验证熔模精密铸造产品的节能减排效果,文章对发动机罩进行生命周期评价。结合熔模铸造工艺设计出满足刚度和模态性能要求的发动机罩,建立发动机罩全生命周期评价模型;追踪生命周期能耗和温室气体(greenhouse gases,GHG... 详细信息

为实现汽车轻量化,验证熔模精密铸造产品的节能减排效果,文章对发动机罩进行生命周期评价。结合熔模铸造工艺设计出满足刚度和模态性能要求的发动机罩,建立发动机罩全生命周期评价模型;追踪生命周期能耗和温室气体(greenhouse gases,GHG)排放,并进行敏感性分析。结果表明:通过一体化集成设计使铸铝发动机罩的质量减轻17.87%,全生命周期能耗降低10.18%,GHG排放减少7.12%。该铸铝发动机罩生命周期评价结果满足节能减排要求,研究为汽车绿色低碳化设计提供了理论依据。

关键词：轻量化发动机罩全生命周期评价中国轻型客车试验循环(CLTC-P) 敏感性分析

Stereoselective C(sp^3)-C(sp^2) Negishi coupling of (2-amido-1-phenylpropyl)zinc compounds through the steric control of β-amido group

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Science China Chemistry 2013年第9期56卷 1293-1300页

作者： TANG Shi li shuhua ZHOU Dong ZENG HuiQiong WANG NaiXing College of Chemistry and Chemical Engineering Jishou University Technical Institute of Physics and chemistry Chinese Academy of Sciences

A controllable diastereoselective C(sp2)-C(sp3) Negishi coupling reaction of secondary benzylic zinc reagents with aryl bromides has been demonstrated for the first time, forming medicinally important 1-arylphenylethylamines. In the presence of Pd(OAc) 2 and S-phos, open-chain (2-amido-1-phenylethyl)zinc reagents bearing a -NHAc or NHCHO group underwent cross-coupling reaction to give syn 1-arylphenylethylamine as the major products, whereas the zinc reagents bearing a sterically hindered-NHCOC(CH3)2 OTBS group specifically yielded anti 1-arylphenylethylamines.

关键词： stereoselective Negishi coupling benzylic zinc 1-arylphenylethylamine aryl bromide

基于有限元法的油气田集输管网阴极保护布局优化

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腐蚀与防护 2024年第3期45卷 88-93页

作者：曾维国李曙华余文正徐东刘博宇范峥中国特种设备检测研究院北京100029 中国石油长庆油田分公司气田开发事业部西安710021 西安长庆工程建设监理有限公司西安710016 中国石油长庆油田分公司第二采气厂榆林719000 西安石油大学石油工程学院西安710065 西安石油大学化学化工学院西安710065

在利用有限元法建立外加电流阴极保护模型的基础上,借助Sobol灵敏度分析,确定了显著影响某油气田集输管网阴极保护效果的关键参数,并通过粒子群优化(PSO)算法对其系统布局进行优化。结果表明:由于外加电流阴极保护模型的模拟电位与测试... 详细信息

在利用有限元法建立外加电流阴极保护模型的基础上,借助Sobol灵敏度分析,确定了显著影响某油气田集输管网阴极保护效果的关键参数,并通过粒子群优化(PSO)算法对其系统布局进行优化。结果表明:由于外加电流阴极保护模型的模拟电位与测试桩的测定电位误差较小,故该模型能够较好地反映出油气田集输管网的电位分布现状;改变防护涂层电阻率等一阶敏感性系数较高的因素会对阴极保护效果产生较大影响,土壤电阻率、防护涂层电阻率以及管道埋深与其他参数之间可能存在明显交互作用;当利用PSO算法对油气田集输管网的阴极保护效果进行全局寻优时,该模型经过47700次粒子进化迭代后的最佳阴极保护系统有效覆盖率高达99.14%,优化效果显著。

关键词：油气田集输管网阴极保护有限元法 Sobol灵敏度分析 PSO算法优化