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Synthesis of amidines via iron-catalyzed dearomative amination of β-naphthols with oxadiazolones

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Organic Chemistry Frontiers 2022年第2期9卷 380-385页

作者： Yan-Hui Fan Xiao-Yu Guan wen-pei li Cheng-Zhou lin De-Xian Bing Mei-Zhi Sun Guo Cheng Jing Cao Jun-Jie Chen Qing-Hai Deng The Education Ministry Key Lab of Resource Chemistry Joint International Research Laboratory of Resource ChemistryMinistry of EducationShanghai Key Laboratory of Rare Earth Functional Materialsand Shanghai Frontiers Science Center of Biomimetic CatalysisCollege of Chemistry and Materials ScienceShanghai Normal UniversityShanghai 200234China

An iron-catalyzed dearomative amination of β-naphthols via a nitrene-transfer process has been ***,which have rarely been applied for the synthesis of amidines,are used as the nitrene source.A variety of amidines bearing β-naphthalenone moieties were generated smoothly in good to high yields(up to 98%)in the presence of 1.5 equivalents of tetrabutylammonium bromide,which was added as an essential additive.

关键词： catalyzed smoothly additive

铁精粉制备α-Fe_(2)O_(3)纳米粒子及其机理

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东北大学学报（自然科学版） 2023年第2期44卷 206-214页

作者：李婷裴文利陈婉晴佟冰东北大学材料科学与工程学院辽宁沈阳110819 东北大学材料各向异性与织构教育部重点实验室辽宁沈阳110819 抚顺罕王傲牛矿业股份有限公司辽宁抚顺113125

采用商业磁铁矿铁精粉(Fe_(3)O_(4)),设计了提纯和制备工艺,成功制备出质量分数为99.5%以上、分散性良好的α-Fe_(2)O_(3)纳米粒子,对其提纯、制备工艺及机理进行了深入研究.结果表明:w NaOH对除硅效果影响显著,当w NaOH为39%时,可使原... 详细信息

采用商业磁铁矿铁精粉(Fe_(3)O_(4)),设计了提纯和制备工艺,成功制备出质量分数为99.5%以上、分散性良好的α-Fe_(2)O_(3)纳米粒子,对其提纯、制备工艺及机理进行了深入研究.结果表明:w NaOH对除硅效果影响显著,当w NaOH为39%时,可使原料矿粉中w SiO 2由1.11%降至0.032%,得到较纯铁精粉;随烧结温度的升高,α-Fe_(2)O_(3)颗粒的结晶度、形貌特征及磁性能随之发生变化;当烧结温度为670℃时,α-Fe_(2)O_(3)颗粒综合性能最佳,颗粒结晶度较高、分散性较好,具有亚铁磁性;通过对氢氧化铁沉淀物加热搅拌时间的控制,可有效调控α-Fe_(2)O_(3)的晶粒尺寸;当搅拌时间为60 min时,获得分散性好、平均粒径仅为35.3 nm的α-Fe_(2)O_(3)纳米粒子.

关键词： α-Fe_(2)O_(3) 铁精粉纳米颗粒晶粒尺寸分散性

ALGEBRA THEORY OF SOFT ALGEBRA

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ALGEBRA THEORY OF SOFT ALGEBRA

铁路货运中一种分布式XML/EDI模型的研究

中南模糊数学与系统理论和应用成果交流会

作者： pei li-wen (Dept.of Math.,Wuhan University,China)

Just as the Boolean algebra is algebra theory of sets theory,so the soft algebra is algebra of fuzzy sets *** the law of the complement is replaced by De Morgen,the Boolean algebra is called a soft algebra,As a consequence the soft algebra is generalization of Boolean *** this paper we shall investigate what results are held and what new results are generated in the soft algebra.

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铁道学报 2003年第6期25卷 21-26页

作者：孙辉梁佩鹏李文大连铁道学院软件学院辽宁大连116028

为了使客户在货物发出后可以实时地了解到货情况,加强EDI与电子商务在铁路货运领域中的应用,文章引入了一种分布式XML/EDI模型,并对其框架和特点进行了分析。该模型在EDI报文上采用XML实现,支持对报文进行合法性检查以及进行数字签名和... 详细信息

为了使客户在货物发出后可以实时地了解到货情况,加强EDI与电子商务在铁路货运领域中的应用,文章引入了一种分布式XML/EDI模型,并对其框架和特点进行了分析。该模型在EDI报文上采用XML实现,支持对报文进行合法性检查以及进行数字签名和加密,在结构上采用分布式体系结构,各功能模块由Java编程实现。最后以实例的形式给出铁路货运EDI原型系统开发的一个完整流程。

关键词： EDI 电子商务 XML Java

ST-Segment Elevation Myocardial Infarction Patients Complicated by Out-of-Hospital Cardiac Arrest May Not Benefit from Emergency Percutaneous Intervention

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Chinese Medical Journal 2018年第6期131卷 746-747页

作者： Kun Wang Yu Shen pei-wen li Rong Go Jing-Mei Zhang lian Wang Jian Bai Biao Xu Department of Cardiology Drum Tower Hospital of Nanjing Medical University Nanjing Jiangsu 210008 China

To the Editor： Out-of-hospital cardiac arrest （OHCA） of cardiac origin is one of the leading causes of death in the industrialized world. The American Heart Association recommended patients who have been successfully resuscitated from OHCA and whose initial electrocardiogram （ECG） showing ST-segment elevation myocardial infarction （STEMI） should undergo emergent cardiac catheterization with the intent to identify and revascularize the culprit lesion by percutmleous intervention （PCI） when clinically applicable. However, few recent retrospective studies and prospective registries observed a beneficial effect of emergency coronary angiography and PCI on the outcome of resuscitated patients with OHCA.

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Depression mechanism of sulfite ions on sphalerite and Pb^(2+)activated sphalerite in the flotation separation of galena from sphalerite

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International Journal of Minerals,Metallurgy and Materials 2025年第2期32卷 335-345页

作者： Feng Zhang Chenyang Zhang linlin Wu Wei Sun Hongliang Zhang Jianhua Chen Yong pei Songjiang li Engineering Research Center of Ministry of Education for Carbon Emission Reduction in Metal Resource Exploitation and Utilization Hunan International Joint Research Center for Efficient and Clean Utilization of Critical Metal Mineral ResourcesSchool of Minerals Processing and BioengineeringCentral South UniversityChangsha 410083China State Key Laboratory of Mineral Processing Beijing General Research Institute of Mining&MetallurgyBeijing 100160China Hunan Provincial Key Laboratory of Micro&Nano Materials Interfaces Science College of Chemistry and Chemical EngineeringCentral South UniversityChangsha 410083China School of Resources Environment and MaterialsGuangxi UniversityNanning 530004China Department of Chemistry Xiangtan UniversityXiangtan 411105China China Railway Resource Group Co.Ltd Beijing 102300China

The depression mechanism of sulfite ions on sphalerite and Pb^(2+)activated sphalerite in the flotation separation of galena from sphalerite still lacked in-depth ***,the depression mechanism of sulfite ions on sphalerite and Pb^(2+)activated sphalerite in the flotation separation of galena from sphalerite was further systematically investigated with experiments and density functional theory(DFT)*** X-ray photoelectric spectroscopy(XPS)results,DFT calculation results,and frontier molecular orbital analysis indicated that sulfite ions were difficult to be adsorbed on sphalerite surface,suggesting that sulfite ions achieved depression effects on sphalerite through other non-adsorption ***,the oxygen content in the surface of sphalerite treated with sulfite ions in creased,which enhanced the hydrophilicity of the sphalerite and further increased the difference in hydrophilicity between sphalerite and ***,sulfite ions were chelated with lead ions to form PbSO_(3)in *** hydrophilic PbSO_(3)was more easily adsorbed on sphalerite than *** interaction between sulfite ions and lead ions could effectively inhibit the activation of *** addition the UV spectrum showed that after adding sulfite ions,the peak of perxanthate in the sphalerite treated xanthate solution was significantly stronger than that in the galena with xanthate solution,indicating that xanthate interacted more readily with sulfite ions and oxygen mo lecules within the sphalerite system,leading to the formation of ***,sulfite ions hardly depressed the flotation of ga lena and could promote the flotation of galena to some *** study deepened the understanding of the depression mechanism o sulfite ions on sphalerite and Pb^(2+)activated sphalerite.

关键词： sphalerite galena sulfite ion density functional theory depression mechanism

NdFeB磁体的Dy热扩渗过程及其矫顽力提高机制

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东北大学学报（自然科学版） 2022年第4期43卷 517-523页

作者：刘富刚赵东向令裴文利东北大学材料科学与工程学院辽宁沈阳110819 东北大学材料各向异性与织构教育部重点实验室辽宁沈阳110819

采用回收料制备的商业35M磁体作为研究对象,使用自制新型DyF_(3)涂料对磁体进行热扩渗处理.研究表明:新型涂料具有速干、附着力好、涂覆均匀的特点,有效改善了热扩渗工艺的稳定性;该磁体经过920℃×10 h的热扩渗处理,获得了良好的综合... 详细信息

采用回收料制备的商业35M磁体作为研究对象,使用自制新型DyF_(3)涂料对磁体进行热扩渗处理.研究表明:新型涂料具有速干、附着力好、涂覆均匀的特点,有效改善了热扩渗工艺的稳定性;该磁体经过920℃×10 h的热扩渗处理,获得了良好的综合磁性能,磁体矫顽力提高到1710.2 kA/m,增幅为37.9%.微观结构分析揭示了Dy元素的扩渗过程和磁体矫顽力提高机理.Dy元素沿晶界扩渗,在主相晶粒周围形成了各向异性场更高(Nd,Dy)_(2)Fe_(14)B的富Dy壳层,使晶界富Nd相变得更加连续、清晰,导致磁体矫顽力大幅增加.

关键词： NdFeB磁体晶粒尺寸晶界扩渗矫顽力 Dy扩渗过程

NdFeCoBZrGa合金各向异性磁粉的制备

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东北大学学报（自然科学版） 2008年第6期29卷 853-856页

作者：尤俊华连法增王继杰裴文利东北大学材料各向异性与织构教育部重点实验室辽宁沈阳110004 沈阳航空工业学院材料工程系辽宁沈阳110034

HDDR(氢化-歧化-脱氢-再结合)工艺是一种用于生产各向异性Nd2Fe14B基磁粉的有效方法.主要研究了真空HDDR工艺(即合金在真空中以较快速率加热到820℃左右,然后在一定的氢气压力下吸氢歧化)及添加合金元素Ga对Nd13Fe64.4-yCo16B6.5Zr0.1Ga... 详细信息

HDDR(氢化-歧化-脱氢-再结合)工艺是一种用于生产各向异性Nd2Fe14B基磁粉的有效方法.主要研究了真空HDDR工艺(即合金在真空中以较快速率加热到820℃左右,然后在一定的氢气压力下吸氢歧化)及添加合金元素Ga对Nd13Fe64.4-yCo16B6.5Zr0.1Gay(y=0.1,0.3,0.5,1.0)合金磁性能的影响规律.结果表明,真空HDDR工艺的吸氢歧化阶段是促使材料产生磁各向异性的关键,脱氢阶段采用低真空高温制度是材料获得高各向异性的保证;合金元素Ga有助于细化主相晶粒,提高材料的综合磁性能,其最佳原子分数添加量为0.5%;成分为Nd13Fe63.9Co16B6.5Zr0.1Ga0.5的合金经真空HDDR工艺处理,其最佳磁性能为:iHc=1 018 kA.m-1,Br=1.32 T,(BH)max=118.6 kJ.m-3,DOA=0.787.

关键词： Nd2Fe14B 真空HDDR 磁粉晶粒尺寸

Real-world evidence on the efficacy and safety of vonoprazanamoxicillin dual therapy for Helicobacter pylori treatment in elderly patients

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World Journal of Gastroenterology 2025年第1期31卷 68-78页

作者： wen Gao Jing-wen li Hui Ye Xue-Zhi Zhang Jian-Xiang liu Hong Cheng Department of Gastroenterology Peking University First HospitalBeijing 100034China School of Medicine Tsinghua MedicineTsinghua UniversityBeijing 100034China Department of Traditional Chinese Medicine and Integrative Medicine Peking University First HospitalBeijing 100034China

BACKGROUND A dual therapy regimen containing amoxicillin is a common treatment option for the eradication of Helicobacter pylori(***).While substantial research supports the efficacy and safety of vonoprazan and amoxicillin(VA)dual therapy in the general population,there is still a lack of studies specifically focusing on its safety in elderly *** To evaluate efficacy and safety of VA dual therapy as first-line or rescue treatment for *** in elderly *** As a real-world retrospective study,data were collected from elderly patients aged 60 years and above who accepted VA dual therapy(vonoprazan 20 mg twice daily+amoxicillin 1000 mg thrice daily for 14 days)for *** eradication in the Department of Gastroenterology at Peking University First Hospital between June 2020 and January *** status was evaluated by^(13)C-urease breath test 6 weeks after *** adverse events(AEs)during treatment were *** In total,401 cases were ***-one cases were excluded due to loss to follow-up,lack of re-examination,or unwillingness to take *** total of 380 included cases comprised 250 who received VA dual therapy as first-line treatment and 130 who received VA dual therapy as rescue *** was successfully eradicated in 239 cases(95.6%)in the first-line treatment group and 116 cases(89.2%)in the rescue treatment *** overall incidence of AEs was 9.5%for both ***,9.2%of patients experienced an AE in the first-line treatment group and 10.0%in the rescue treatment *** patients discontinued treatment due to AE,with a discontinuation rate of 1.3%.No serious AE *** The VA dual therapy regimen as a first-line treatment and a rescue therapy was effective and safe for elderly patients aged 60 and older.

关键词： Helicobacter pylori Vonoprazan Amoxicillin Dual therapy Elderly