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Flavor SU(3)topological diagram and irreducible representation amplitudes for heavy meson charmless hadronic decays:mismatch and equivalence

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Chinese Physics C 2018年第10期42卷 59-68页

作者： Xiao-gang he Wei Wang T.-D.Lee Institute and INPAC Shanghai Key Laboratory for Particle Physics and CosmologyMOE Key Laboratory for Particle PhysicsSchool of Physics and AstronomyShanghai Jiao Tong UniversityShanghai 200240 Department of Physics National Taiwan UniversityTaipei 106 National Center for Theoretical Sciences TsingHua UniversityHsinchu 300

Flavor SU（3） analysis of B meson charmless hadronic two light pseudoscalar decays can be formulated in two different ways. One is to construct the SU（3） irreducible representation amplitude （IRA） according to effective Hamiltonian transformation properties, and the other is to draw the topological diagrams （TDA）. We first point out that previous analyses of TDA and IRA approaches do not match in several aspects, in particular a few SU（3） independent amplitudes have been overlooked in the TDA approach. This has caused confusions in the past and sometimes resulted in incorrect interpretation of data. We then demonstrate that only if these amplitudes are included, a consistent and unified picture can be obtained. With the new TDA amplitudes, all charmless hadronic decays of heavy meson must have nonzero direct CP symmetries as already predicted by the IRA approach. In addition to their notable impact on CP asymmetry, the new amplitudes are also important to extract new physics information.

关键词： heavy flavor physics flavor SU(3) symmetry topological diagrams

DNA damage,apoptosis and cell cycle changes induced by fluoride in rat oral mucosal cells and hepatocytes

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World Journal of Gastroenterology 2006年第7期12卷 1144-1148页

作者： Ling-Fei he lian-gang Chen Department of Dental Medicine Zhongnan Hospital Wahan University Wuhan 430071 Hubei Province China

AIM： To study the effect of fluoride on oxidative stress, DNA damage and apoptosis as well as cell cycle of rat oral mucosal cells and hepatocytes.METHODS： Ten male SD rats weighing 80N120 g were randomly divided into control group and fluoride group, 5 animals each group. The animals in fluoride group had free access to deionized water containing 150 mg/L sodium fluoride （NaF）. The animals in control group were given distilled water. Four weeks later, the animals were killed. Reactive oxygen species （ROS） in oral mucosa and liver were measured by Fenton reaction, lipid peroxidation product, malondialdehyde （MDA）, was detected by thiobarbituric acid （TBA） reaction, reduced glutathione （GSH） was assayed by dithionitrobenzoic acid （DTNB） reaction. DNA damage in oral mucosal cells and hepatocytes was determined by single cell gel （SCG） electrophoresis or comet assay. Apoptosis and cell cycle in oral mucosal cells and hepatocytes were detected by flow cytometry.RESULTS： The contents of ROS and MDA in oral mucosa and liver tissue of fluoride group were significantly higher than those of control group （P〈 0.01）, but the level of GSH was markedly decreased （P〈 0.01）. The contents of ROS, MDA and GSH were （134.73 ＋ 12.63） U/mg protein, （1.48 ＋ 0.13） mmol/mg protein and （76.38 ~ 6.71） mmol/ mg protein in oral mucosa respectively, and （143.45＋ 11.76） U/mg protein, （1.44：1：0.12） mmol/mg protein and （78.83±7.72） mmol/mg protein in liver tissue respectively. The DNA damage rate in fluoride group was 50.20% in oral mucosal cells and 44.80% in hepatocytes, higher than those in the control group （P 〈0.01）. The apop- tosis rate in oral mucosal cells was （13.63 ＋ 1.81） % in fluoride group, and （t2.76＋ 1.67） % in hepatocytes, higher than those in control group. Excess fluoride could differently lower the number of oral mucosal cells and hepatocytes at G0/G1 and S G2/M phases （P〈 0.05）.CONCLUSION： Excess fluoride can induce oxidative stress and DNA damage and lead to apoptosis an

关键词： Fluoride Oxidative stress DNA damage Apoptosis Cell cycle

对比经肛括约肌间切开术和切开挂线法治疗高位肛瘘对患者肛门功能恢复和复发的影响

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中国现代药物应用 2024年第2期18卷 27-30页

作者：何志刚何永忠谢伟何海广州市番禺区沙湾人民医院 511483 广州市番禺区何贤纪念医院 511400

目的探讨经肛括约肌间切开术和切开挂线法治疗高位肛瘘的临床疗效及其对患者肛门功能恢复和复发的影响。方法91例高位肛瘘患者,根据手术方法的不同分为经肛括约肌间切开组(50例)和切开挂线组(41例)。经肛括约肌间切开组患者采用经肛括... 详细信息

目的探讨经肛括约肌间切开术和切开挂线法治疗高位肛瘘的临床疗效及其对患者肛门功能恢复和复发的影响。方法91例高位肛瘘患者,根据手术方法的不同分为经肛括约肌间切开组(50例)和切开挂线组(41例)。经肛括约肌间切开组患者采用经肛括约肌间切开术进行治疗,切开挂线组患者采用切开挂线法进行治疗。比较两组患者临床疗效、临床指标(手术时间、愈合时间、术中出血量及住院时间)、视觉模拟评分法(VAS)评分、大便失禁严重度(Wexner)评分、肛门功能及复发情况。结果治疗后经肛括约肌间切开组临床总有效率96.00%高于切开挂线组的78.05%(P<0.05)。经肛括约肌间切开组患者手术时间(58.98±3.71)min、愈合时间(22.24±1.71)d及住院时间(9.38±1.59)d均短于切开挂线组的(75.73±2.95)min、(27.44±1.86)、(14.73±2.05)d,术中出血量(84.96±2.85)ml少于切开挂线组的(96.07±2.71)ml(P<0.05)。术后1个月,两组VAS评分与Wexner评分均较本组术前降低,且经肛括约肌间切开组VAS评分(1.54±0.61)分与Wexner评分(1.22±0.42)分均低于切开挂线组的(2.17±0.70)、(1.93±0.82)分(P<0.05)。术后3个月,两组肛管最大收缩压与肛管最大静息压均较本组术前降低,但经肛括约肌间切开组肛管最大收缩压(16.23±1.62)kPa与肛管最大静息压(8.03±1.01)kPa均大于切开挂线组的(11.17±1.78)、(4.38±0.92)kPa(P<0.05)。结论相较于切开挂线法,经肛括约肌间切开术在高位肛瘘中的临床疗效更加理想,可有效促进患者恢复,同时减轻患者疼痛程度,保护患者肛门功能。

关键词：高位肛瘘切开挂线法经肛括约肌间切开术肛门功能

基于低氮燃烧技术的600 MW机组锅炉燃烧器优化改造

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工业炉 2024年第1期46卷 34-37页

作者：何刚周洪王伟曾建贵州省习水鼎泰能源开发有限责任公司

针对燃煤电厂NOx的治理主要有末端治理和源头治理两类方法，采用两类治理方法相结合(即低氮燃烧+SCR)的方案在已有电厂改造中取得的效果较为显著。基于此，介绍了燃煤电厂NOx的形成机理，分析了锅炉NOx排放值偏高的原因。以600 MW机组... 详细信息

针对燃煤电厂NOx的治理主要有末端治理和源头治理两类方法，采用两类治理方法相结合(即低氮燃烧+SCR)的方案在已有电厂改造中取得的效果较为显著。基于此，介绍了燃煤电厂NOx的形成机理，分析了锅炉NOx排放值偏高的原因。以600 MW机组锅炉为例，在不改变原SCR系统的基础上对燃烧系统进行低氮燃烧技术改造，通过试验分析了改造前后锅炉NOx排放的变化以及改造对锅炉的影响。

关键词：低氮燃烧燃烧器氮氧化物燃尽风

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政策工具视角下四川养老产业政策量化研究

西部经济管理论坛 2024年第4期35卷 76-85页

作者：贺刚唐李翊茉汪雨腈西华大学经济学院四川成都611730

随着老年健康服务需求的不断增加,四川省陆续推出多项促进地方养老产业发展的养老产业政策。为识别政策供给和产业发展需求之间的差距,文章构建了包含模式维、链条维和工具维在内的三维政策分析框架,采用内容分析法和词云图分析法对四川... 详细信息

随着老年健康服务需求的不断增加,四川省陆续推出多项促进地方养老产业发展的养老产业政策。为识别政策供给和产业发展需求之间的差距,文章构建了包含模式维、链条维和工具维在内的三维政策分析框架,采用内容分析法和词云图分析法对四川省2011—2023年制定的养老产业政策文本进行了量化分析。分析结果表明,四川养老产业政策中供给型政策的占比偏大,总体而言均衡性不足;养老产业发展模式的政策导向比较模糊,家庭养老保障政策不完善;针对养老产业链的政策系统性有待加强。基于上述结论,文章提出了相应的对策建议:合理配置各类型政策工具,制定有针对性的养老产业发展政策,合理布局政策体系。

关键词：政策工具养老产业内容分析法词云图政策文本

Synthesis of non-classical heteroaryl C-glycosides via Minisci-type alkylation of N‑heteroarenes with 4-glycosyl-dihydropyridines

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Science China Chemistry 2020年第11期63卷 1613-1618页

作者： Qingbing Wang Juan Duan Pingping Tang Gong Chen gang he State Key Laboratory and Institute of Elemento-Organic Chemistry College of ChemistryNankai UniversityTianjin 300071China

A radical-mediated method was reported for diastereoselective synthesis of non-classical heteroaryl C-glycosides via Minisci-type alkylation of N-heteroarenes with 4-glycosyl-1,4-dihydropyridine(DHP)*** DHP reagents serve as convenient precursors for various glycosyl radicals under the activation of single electron transfer(SET)oxidation by persulfate and visible light irradiation with or without photocatalyst.

关键词： non-classical C-glycoside Minisci reaction 4-gIycosyl-dihydropyridine

Highly thermal-conductive graphite flake/Cu composites prepared by sintering intermittently electroplated core-shell powders

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Journal of Materials Science & Technology 2021年第2期61卷 93-99页

作者： Hong Sun Nan Deng Jianqiang Li gang he Jiangtao Li National Engineering Laboratory for Hydrometallurgical Cleaner Production Technology CAS Key Laboratory of Green Process and Engineering.Institute of Process EngineeringChinese Academy of SciencesBeijing100190China University of Chinese Academy of Sciences Beijing100049China School of Materials Science and Engineering University of Science and Technology BeijingBeijing100083China Technical Institute of Physics and Chemistry Chinese Academy of SciencesBeijing100190China

Graphite flake/Cu composite has attracted tremendous attention as a promising heat sinks materials owing to its easy machinability and superior thermal properties. However, its preparation process still faces several technological limitations including complex, time-consuming and costly synthetic approaches. In this work, a facile and scalable intermittently electroplated method is applied to prepare Cu-coated graphite flake composite powders, which are subsequently sintered into dense composite bulks. The results show that the graphite flake is successfully coated with a uniform and compact Cu shell,which effectively inhibits the segregation accumulation of graphite flakes and contributes to homogeneous distribution of graphite in the sintered graphite flake/Cu composites. The as-sintered composites exhibit an excellent thermal conductivity of 710 W·m-1·K-1and an outstanding bending strength of 93 MPa. Such performance, together with the simple, efficient powder-preparation process, suggests that the present strategy may open up opportunities for the development of thermal management materials.

关键词： Graphite flake Electroplating Powder processing Thermal properties

Microstructure and properties of porous Si_(3)N_(4)ceramics by gelcasting-self-propagating high-temperature synthesis(SHS)

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Journal of Advanced Ceramics 2022年第1期11卷 172-183页

作者： Shile CheN Liang WANG gang he Jiangtao LI Chang-An WANG State Key Laboratory of New Ceramics and Fine Processing School of Materials Science and EngineeringTsinghua UniversityBeijing 100084China CAS Key Laboratory of Cryogenics Technical Institute of Physics and ChemistryChinese Academy of SciencesBeijing 100190China

Porous silicon nitride ceramics have attracted a considerable attention due to their excellent overall performance,but poor porosity homogeneity and structural shrinkage induced by prolonged high temperature sintering limit its further ***,as a three-in-one solution for the above issues,for the first time we develop a novel approach that integrates the merits of gelcasting-SHS(self-propagating high-temperature synthesis)to prepare porous Si_(3)N_(4)ceramics to simultaneously achieve high porosity,high strength,high toughness,and low thermal conductivity across a wide temperature *** regulating the solid content,porous Si_(3)N_(4)ceramics with homogeneous pore structure are obtained,where the pore size falls inbetween 1.61 and 4.41 pm,and the elongated grains are interlaced and interlocked to form micron-sized coherent interconnected *** the same time,porous Si_(3)N_(4)ceramics with porosity of 67.83%to 78.03%are obtained,where the compressive strength reaches 11.79 to 47.75 MPa and fracture toughness reaches 1.20 to 6.71 MPa-m1/2.

关键词： porous Si_(3)N_(4)ceramics gelcasting self-propagating high-temperature synthesis(SHS) porosity

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MTO脱甲烷塔模拟与优化

广州化工 2024年第6期52卷 180-182页

作者：李祚辉贺杠高翔陕煤集团榆林化学有限责任公司陕西榆林719000

甲醇制烯烃(MTO)技术是将甲醇转化为低碳烯烃(乙烯、丙烯)的化工工艺,与传统蒸汽裂解工艺相比,甲醇制烯烃(MTO)产品气中氢气、甲烷、一氧化碳等轻组分含量少;脱甲烷塔在甲醇制烯烃(MTO)产品气分离中的主要作用是在塔顶分离轻组分,最终... 详细信息

甲醇制烯烃(MTO)技术是将甲醇转化为低碳烯烃(乙烯、丙烯)的化工工艺,与传统蒸汽裂解工艺相比,甲醇制烯烃(MTO)产品气中氢气、甲烷、一氧化碳等轻组分含量少;脱甲烷塔在甲醇制烯烃(MTO)产品气分离中的主要作用是在塔顶分离轻组分,最终保证乙烯产品中甲烷等轻组分合格;但在实际运行中由于工艺条件的变化导致脱甲烷塔塔顶乙烯损失较大。本文运用Aspen Plus模拟软件,选择RK-SOVE物性方法,应用系统中RadFrac精馏模块对某1 800 kt/a MTO脱甲烷塔进行模拟优化,结合Aspen Plus灵敏度分析工具对相关工艺参数变化对塔顶乙烯损失进行分析,根据灵敏度分析数据指导实际操作。

关键词： MTO 脱甲烷塔乙烯灵敏度