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Deep Learning in Chest Radiography:Detection of Pneumoconiosis

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Biomedical and Environmental Sciences 2021年第10期34卷 842-845页

作者： li Xiao liU chao Fei GUAN li WEI shu YANG Xin li shu Qiang Peking University Third Hospital Beijing 100000China'2.Beijing Tianming Innovation Data Technology Co.LTDBeijing 100000China

Pneumoconiosis,the predominant occupational disease in China and the world,is a pulmonary disease caused by the inhalation of inorganic dust,that is,particulate matter in the solid phase without living organisms[1].As... 详细信息

关键词： occupational irreversible predominant

Enantioselective construction of a congested quaternary stereogenic center in isoindolinones bearing three aryl groups via an organocatalytic formal Betti reaction

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Organic Chemistry Frontiers 2022年第2期9卷 428-435页

作者： Arben Berisa Danijel Glavac chao Zheng shu-li You Matija Gredicak Division of Organic Chemistry and Biochemistry Ruder Boskovic InstituteBijenicka c.5410000 ZagrebCroatia State Key Laboratory of Organometallic Chemistry Shanghai Institute of Organic ChemistryChinese Academy of Sciences345 Lingling LuShanghai 200032China

An efficient enantioselective formal Betti reaction between phenols and diaryl ketimines generated in situ from isoindolinone alcohols is described.In a reaction catalyzed by a chiral phosphoric acid,a broad range of ketimines and phenols afforded isoindolinone derivatives comprising a congested quaternary stereogenic center bearing three aryl groups in high yields,and high regioselectivities and enantioselectivities.

关键词： quaternary formal stereo

Pd-Catalyzed Asymmetric Intramolecular Arylative Dearomatization of para-Aminophenols

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Chinese Journal of Chemistry 2020年第7期38卷 683-689页

作者： Ren-Qi Xu Ping Yang chao Zheng shu-li You State Key Laboratory of Organometallic Chemistry Center for Excellence in Molecular SynthesisShanghai Institute of Organic ChemistryUniversity of Chinese Academy of SciencesChinese Academy of Sciences345 Lingling LuShanghai 200032China

Background and Originality Content.In recent years,Pd-catalyzed arylative dearomatization reactions have attracted wide interests of organic chemists for the efficient construction of privileged molecular scaffolds that appear in important natural products.[l]A large array of aromatic compounds,such as anilines,121 phenols,[3]indoles,[4]pyrroles,[3]pyridines[6]and furans171 have been successfully applied in the arylative dearomatization strategy via Pd-catalyzed cross coupling reactions.

关键词： products. phenols catalyzed

Pd-Catalyzed Dearomatization of Indole Derivatives via Intermolecular Heck Reactions

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Chinese Journal of Chemistry 2020年第3期38卷 235-241页

作者： Ping Yang Ren-Qi Xu chao Zheng shu-li You State Key Laboratory of Organometallic Chemistry Center for Excellence in Molecular SynthesisShanghai Institute of Organic ChemistryUniversity of Chinese Academy of SciencesChinese Academy of Sciences345 Ling ling LuShanghai 200032China

Pd-catalyzed intermolecular dearomative Heck reaction of indoles with aryl iodides is described.The challenges on both reactivity and regioselectivity are addressed by the judicious regulation of the geometric and electronic properties of the substrates.An array of indoline derivatives bearing C2-quaternary center is obtained in good to excellent yields(up to 93%)with exclusive regioselectivity under operationally simple conditions.The mechanistic proposal is supported by detailed DFT calculations.

关键词： conditions. Heck conclusion

Fe(OTf)_(3) Catalyzed Annulation of 2,3-Disubstituted Indoles with Aziridines

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Chinese Journal of Chemistry 2014年第8期32卷 709-714页

作者： Hua liu chao Zheng shu-li You State Key Laboratory of Organometallic Chemistry Shanghai Institute of Organic ChemistryChinese Academy of SciencesShanghai 200032China

A Fe(OTf)_(3) catalyzed[3+2]annulation reaction between 2,3-disubstituted indoles and N-Ts aziridines is described herein.A series of hexahydropyrrolo[3,4-b]indole derivatives bearing two consecutive quaternary carboncenters can be generated efficiently.The reaction features cheap catalyst,mild conditions and operational simplicity.

关键词： annulation indole aziridine Lewis acid catalysis

Agglomeration behavior of alumina inclusions and calcium aluminate inclusions on molten nickel-based superalloy surface

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Journal of Iron and Steel Research(International) 2023年第11期30卷 2318-2327页

作者： Rui-zhi Gao lin-zhu Wang chao-yi Chen shu-feng Yang Xiang li Yin Zhang School of Materials and Metallurgy Guizhou UniversityGuiyang550025GuizhouChina School of Metallurgical and Ecological Engineering University of Science and Technology BeijingBeijing100083China Department of Materials and Metallurgy Engineering Guizhou Institute of TechnologyGuiyang550003GuizhouChina

Understanding the interactive forces of inclusions on the surface of molten nickel-based superalloys and finding methods to disperse these inclusions help improve performance and service life.The aggregation behavior of aluminum oxide(Al_(2)O_(3))and calcium aluminate inclusions with different sizes and spacings on the surface of molten nickel-based superalloys was observed in-situ using a high-temperature confocal laser scan microscope.The attractive force acted on Al2O3 inclusions with radii of 3.5-6μm was found ranging from 6.2×10-18 to 3.6×10-15 N,and that of CaO·2Al2O3(CA2)inclusions with radii of 3-5.5μm ranging from 3.5×10-19 to 8.3×10-15 N.The capillary force acted on inclusions on the surface of nickel-based superalloy was calculated based on the Kralchevsky-Paunov model and investigated as a function of inclusion size,spacing,and composition.The calculated results were in the same trend as the experimental results.The capillary force acted on inclusions was also affected by their contact angle,the density,surface energy,and oxygen content of the molten alloy.It decreased with increasing alloy density and decreasing contact angle between inclusion with alloy.Thus,the attractive force acted on Al2O3 inclusions was smaller on the surface of molten nickel-based superalloy than that of molten steel.Decreasing the oxygen content in the molten nickel-based alloy could increase its surface energy,and the attractive force acted on the inclusions would decrease.When the oxygen content in the molten nickel-based alloy decreased from 0.05 to 0.0001 wt.%,the capillary force acted on the Al2O3 inclusions decreased from 1.7×10-18 to 3.6×10-19 N,reduced by 79%(1.4×10-18 N).

关键词： Inclusion Nickel-based superalloy Capillary force Alumina Calcium aluminate

Changes in soil microbial communities induced by warming and N deposition accelerate the CO 2 emissions of coarse woody debris

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Journal of Forestry Research 2023年第4期34卷 1051-1063页

作者： Hankun Wang Chunsheng Wu Junping liu Qi Chen chao li Chunjie shu Yi Zhang Yuanqiu liu Key Laboratory of Silviculture Co-Innovation Center of Jiangxi Typical Trees Cultivation and UtilizationCollege of ForestryJiangxi Agricultural UniversityZhimin Rd.1101Nanchang 330045People’s Republic of China School of Hydraulic and Ecological Engineering Nanchang Institute of TechnologyNanchang 330099People’s Republic of China Lushan Nature Reserve of Jiangxi(Lushan Mountain National Forest Ecological Station) Henan Rd.600Jiujiang 332900People’s Republic of China College of Forestry and Landscape Architecture South China Agricultural UniversityWushan Rd.483Tianhe DistrictGuangzhou 510642People’s Republic of China College of Biology and the Environment Nanjing Forestry UniversityNanjing 210037People’s Republic of China

Warming and nitrogen(N)deposition are two important drivers of global climate changes.Coarse woody debris(CWD)contains a large proportion of the carbon(C)in the total global C pool.The composition of soil microbial communities and environmental changes(i.e.,N deposition and warming)are the key drivers of CWD decomposition,but the interactive impact between N deposition and warming on the composition of soil microbial communities and CWD decomposition is still unclear.In a laboratory experiment,we study and simulate respiration during decomposition of the CWD(C 98)of Cryptomeria japonica(CR)and Platycarya strobilacea(PL)in response to warming and N deposition over 98 days.Resuts show that either warming or N addition signifi cantly accelerated the C 98 of the two tree species by altering the soil microbial community(bacterial:fungi and G+:G–).The combined treatment(warming+N)resulted in a decomposition eff ect equal to the sum of the individual eff ects.In addition,the species composition of bacteria and fungi was obviously aff ected by warming.However,N deposition had a remarkable infl uence on G+:G–.Our results indicated that N deposition and warming will observably alter the composition and growth of the microbial community and thus work synergistically to accelerate CWD decomposition in forest ecosystems.We also present evidence that N deposition and warming infl uenced the composition and balance of soil microbial communities and biogeochemical cycling of forest ecosystems.

关键词： Warming N deposition Coarse woody debris Decomposition Soil microbial community

Characterization of wheat monogenic lines with known Sr genes and wheat cultivars for resistance to three new races of Puccinia graminis f. sp. tritici in China

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Journal of Integrative Agriculture 2023年第6期22卷 1740-1749页

作者： WU Xian-xin ZANG chao-qun ZHANG Ya-zhao XU Yi-wei WANG shu li Tian-ya GAO li State Key Laboratory for Biology of Plant Disease and Insect Pests Institute of Plant ProtectionChinese Academy of Agricultural SciencesBeijing 100193P.R.China College of Plant Protection Shenyang Agricultural UniversityShenyang 110866P.R.China Institute of Plant Protection Liaoning Academy of Agricultural SciencesShenyang 110161P.R.China Agronomy College Shenyang Agricultural UniversityShenyang 110866P.R.China

Wheat stem rust, caused by Puccinia graminis f. sp. tritici(Pgt), is a potentially devastating fungal disease of wheat worldwide. The present study was to evaluate the resistance of 42 wheat monogenic lines with known stem rust resistance(Sr) genes and 69 wheat cultivars to three new Pgt races(34C0MRGQM, 34C3MKGQM, and 34C6MTGSM)identified from aeciospores at the seedling and adult-plant stages. The phenotyping results revealed that monogenic lines harboring resistance genes Sr9e, Sr17, Sr21, Sr22, Sr26, Sr30, Sr31, Sr33, Sr35, Sr36, Sr37, Sr38, Sr47, SrTmp,and SrTt3 were effectively resistant to all three Pgt races at the seedling and adult-plant stages. In contrast, monogenic lines containing Sr5, Sr6, Sr7b, Sr9a, Sr9d, Sr9f, Sr9g, Sr9b, Sr16, Sr24, Sr28, and Sr39 were highly susceptible to these races at both seedling and adult-plant stages. The other lines with Sr8a, Sr10, Sr11, Sr13, Sr14, Sr15, Sr18, Sr20,Sr19, Sr23, Sr25, Sr27, Sr29, Sr32, and Sr34, displayed variable levels of resistance to one or two of the tested races.Seedling infection types(ITs) and adult-plant infection responses(IRs) indicated that 41(59.4%) of the wheat cultivars showed high resistance to all the three races. Molecular marker analysis showed that four wheat culitvars likely carried Sr2, 20 wheat culitvars likely carried Sr31, 9 wheat culitvars likely carried Sr38, and none of the cultivars carried Sr24,Sr25, and Sr26. Our results provide a scientific basis for rational utilization of the tested Sr genes and wheat cultivars against these novel Pgt races.

关键词： wheat stem rust Puccinia graminis f.sp.tritici wheat cultivars resistance genes

3D Lamellar-Structured Graphene Aerogels for Thermal Interface Composites with High Through-Plane Thermal Conductivity and Fracture Toughness

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Nano-Micro Letters 2021年第2期13卷 13-27页

作者： Pengfei liu Xiaofeng li Peng Min Xiyuan Chang chao shu Yun Ding Zhong-Zhen Yu Beijing Key Laboratory of Advanced Functional Polymer Composites Beijing University of Chemical TechnologyBeijing 100029People’s Republic of China State Key Laboratory of Organic-Inorganic Composites College of Materials Science and EngineeringBeijing University of Chemical TechnologyBeijing 100029People’s Republic of China Beijing Advanced Innovation Center for Soft Matter Science and Engineering Beijing University of Chemical TechnologyBeijing 100029People’s Republic of China

Although thermally conductive graphene sheets are efficient in enhancing in-plane thermal conductivities of polymers,the resulting nanocomposites usually exhibit low through-plane thermal conductivities,limiting their application as thermal interface materials.Herein,lamellarstructured polyamic acid salt/graphene oxide(PAAS/GO)hybrid aerogels are constructed by bidirectional freezing of PAAS/GO suspension followed by lyophilization.Subsequently,PAAS monomers are polymerized to polyimide(PI),while GO is converted to thermally reduced graphene oxide(RGO)during thermal annealing at 300℃.Final graphitization at 2800℃ converts PI to graphitized carbon with the inductive effect of RGO,and simultaneously,RGO is thermally reduced and healed to high-quality graphene.Consequently,lamellar-structured graphene aerogels with superior through-plane thermal conduction capacity are fabricated for the first time,and its superior through-plane thermal conduction capacity results from its vertically aligned and closely stacked high-quality graphene lamellae.After vacuum-assisted impregnation with epoxy,the resultant epoxy composite with 2.30 vol% of graphene exhibits an outstanding through-plane thermal conductivity of as high as 20.0 W m^−1 K^−1,100 times of that of epoxy,with a record-high specific thermal conductivity enhancement of 4310%.Furthermore,the lamellar-structured graphene aerogel endows epoxy with a high fracture toughness,~1.71 times of that of epoxy.

关键词： Anisotropic aerogels Graphene Thermal conductivity Epoxy composites Fracture toughness