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Preliminary study on active features of Fenghuang-shan-Tianshui fault, West Qinling north boundary fault zone since the late of Late Pleistocene

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Acta Seismologica Sinica(English Edition) 2001年第2期14卷 230-233页

作者： HAN zhu-jun Institute of Geology China Seismological Bureau Beijing China

West Qinling north boundary fault zone (WQNBFZ) is a major NWW-striking fault in the east boundary of Tibetan Plateau, which is parallel to the Xianshuihe fault zone, Eastern Kunlun fault zone and Haiyuan fault zone. It is of mainly sinistral strike-slip. England and Molnar (1990) and WANG and MA (1998) proposed that these strike-slip faults divided the east part of Tibetan Plateau into elongate blocks, which slide successively towards the east, accompanied possibly by the clockwise rotation. What is more, the occurrence frequency of earthquakes with M 36.5 along WQNBFZ is also high, such as BC 47 Zhangxian M=6.8 earthquake, the 128 Gangu M=6.5 earth-quake, the 143 Gangu M=7 earthquake, the 734 Tianshui M=7 earthquake, the 1756 Wushan M=6.5 earthquake and the 1936 Kangle M=6.8 earthquake. However, compared with researches on Haiyuan fault zone, Xianshuihe fault zone and Longmenshan fault zone (Institute of Geology of State Seismological Bureau, Seismological Bureau of Ningxia Hui Autonomous Region, 1990; LI, 1993; DENG, et al, 1994; Burchfiel, et al, 1995), the study on WQNBFZ is still weak, although some researches have been done by KANG (1990) and TENG, et al (1991). Based on the field investigation and sample dating, the active features about the Fenghuangshan-Tianshui fault (FTF) of WQNBFZ are discussed in the paper.……

关键词： Late Pleistocene

Michael addition-based cyclization strategy in the total synthesis of Lycopodium alkaloids

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Science China Chemistry 2016年第9期59卷 1079-1087页

作者： Lin-Rui Zhong zhu-jun Yao State Key Laboratory of Coordination Chemistry Institute of Chemical Biology and Drug Innovation School of Chemistry and Chemical Engineering Collaborative Innovation Center of Chemistry for Life Sciences Nanjing University

Lycopodium alkaloids, a unique family of biologically important natural products isolated and characterized from various species of Lycopodium(sensu lato), have attracted extensive attention from chemists and pharmacists in the past three decades. Michael addition-based cyclization has been successfully employed as an elegant and efficient ring-construction protocol of constructing key cyclohexanone intermediates in the total synthesis of Lycopodium alkaloids. This mini-review chooses and summarizes several representative total syntheses of various Lycopodium alkaloids in which intramolecular Michael addition severed as the key methodology.

关键词： Lycopodium alkaloid Michael addition cyclization total synthesis

Towards automatic freeform optics design: coarse and fine search of the three-mirror solution space

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Light(Science & Applications) 2021年第4期10卷 660-670页

作者： Benqi Zhang Guofan Jin jun zhu State Key Laboratory of Precision Measurement Technology and Instruments Departm ent of Precision InstrumentTsinghua UniversityBeijing 100084China

Design of an optical system,whether classic or novel,in the past or the present,requires significant effort from the *** addition to design methods and theories,the designer’s skills and experience in optical system design are particularly important,which may require years of practice to *** diversity and variety of results are limited because of the difficulty,time,and labor costs *** this article,we propose an automatic design method for freeform optics that can achieve a diverse range of three-mirror *** optical specifications and the design constraints are the only inputs required,and a variety of results can be obtained *** output results have various structures and various optical power distributions with high imaging *** implementing the design method,designers can not only realize an overview of the solution space of the three-mirror freeform system,but can also focus on specific designs.

关键词： mirror optics system

Decontamination of Cr(Ⅵ) from water using sewage sludge-derived biochar: Role of environmentally persistent free radicals

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Chinese Journal of Chemical Engineering 2023年第4期56卷 97-103页

作者： Yuhan zhu Jia Wei jun Li Faculty of Architecture Civil and Transportation EngineeringBeijing University of TechnologyBeijing 100124China

Biochar is a well-known material for pollutant removal owing to its low cost and rich surface functionality. A kind of highly active substance, called environmentally persistent free radicals(EPFRs), can be produced in the preparation process of biochar, playing an important role in the removal of *** this study, sludge-derived biochars(SBC_(120) and SBC_(270)) were prepared by the hydrothermal carbonization under two temperatures(120℃ and 270℃) to investigate their removal abilities of Cr(Ⅵ). The maximum removal amounts of Cr(Ⅵ) by SBC_(120) and SBC_(270) were 16.58 and 22.93 mg·g^(-1), respectively. It was further revealed that the appearance of Cr(Ⅲ), as a result of EPFRs on sludge-derived biochar(SBC) transferred electrons to Cr(Ⅵ) in neutral solutions. That is to say, oxygen-centered(O-centered) EPFRs on SBC_(120) and carbon-centered(C-centered) EPFRs on SBC_(270) all could be used as electron donors to Cr(Ⅵ) to make it become Cr(Ⅲ). This study not only provides a theoretical basis for the mechanism of pollutants removal by sludge-derived biochar but also offers a new perspective on the direct effect of EPFRs on pollutants.

关键词： Sludge-derived biochar Environmentally persistent free radicals Chromium Removal Reduction

Gut microbiota and transcriptome response of earthworms(Metaphire guillelmi)to polymyxin B exposure

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Journal of Environmental Sciences 2023年第11期133卷 37-47页

作者： jun Zhao Guilan Duan Yongguan zhu Dong zhu State Key Lab of Urban and Regional Ecology Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China University of Chinese Academy of Sciences Beijing 100049China Key Laboratory of Urban Environment and Health Institute of Urban EnvironmentChinese Academy of SciencesXiamen 361021China

Polymyxin B(PMB)has received widespread attention for its use as a last-line therapy against multidrug-resistant bacterial ***,the consequences of unintended PMB exposure on organisms in the surrounding environment remain ***,this study investigated the effects of soil PMB residue on the gut microbiota and transcriptome of earthworms(Metaphire guillelmi).The results indicated that the tested doses of PMB(0.01–100 mg/kg soil)did not significantly affect the richness and Shannon’s diversity index of the earthworm gut microbiota,but PMB altered its community structure and taxonomic ***,PMB significantly affected Lysobacter,Aeromonas,and Sphingomonas in the soil microbiota,whereas Pseudomonas was significantly impacted the earthworm gut ***,active bacteria responded more significantly to PMB than the total microbial *** genera such as Acinetobacter and Bacillus were highly correlated with differential expression of some genes,including up-regulated genes associated with folate biosynthesis,sulphur metabolism,and the IL-17 signalling pathway,and downregulated genes involved in vitamin digestion and absorption,salivary secretion,other types of O-glycan biosynthesis,and the NOD-like receptor signalling *** results suggest that adaptation to PMB stress by earthworms involves changes in energy metabolism,their immune and digestive systems,as well as glycan *** study findings help elucidate the relationship between earthworms and their microbiota,while providing a reference for understanding the environmental risks of PMB.

关键词： Microbiome Antibiotic Soil fauna Active microbiota Transcriptome

Could π-aromaticity cross an unsaturated system to a fully saturated one?

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Chinese Chemical Letters 2024年第6期35卷 298-302页

作者： Shicheng Dong jun zhu State Key Laboratory of Physical Chemistry of Solid Surfaces Collaborative Innovation Center of Chemistry for Energy Materials(iChem)Fujian Provincial Key Laboratory of Theoretical and Computational ChemistryCollege of Chemistry and Chemical EngineeringXiamen UniversityXiamen 361005China School of Science and Engineering The Chinese University of Hong KongShenzhen 518172China

The classification of π-/σ-aromaticity depends on the electrons with the dominating ***,π-andσ-aromaticity are used to describe the unsaturated and saturated systems,***,it is rarely reported that π-aromaticity is dominated in a saturated *** we demonstrate that π-aromaticity could be dominating in several fully saturated four-membered rings(4MRs),supported by various aromaticity indices including ΔBL,NICS,EDDB,MCI,and Ad *** origin of suchπ-aromaticity in saturated rings could be attributed to an introduction of two additional electrons into the π-type LUMO of the parent neutral *** findings represent a novel approach to achieve π-aromaticity into a fully saturated system which has traditionally been dominated by σ-aromaticity.

关键词： π-Aromaticity Saturated rings Silicon

Antiaromaticity-promoted radical anion stability in α-vinyl heterocyclics

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Organic Chemistry Frontiers 2022年第5期9卷 1427-1436页

作者： Lu Lin jun zhu State Key Laboratory of Physical Chemistry of Solid Surfaces Fujian Provincial Key Laboratory of Theoretical and Computational ChemistryDepartment of ChemistryCollege of Chemistry and Chemical EngineeringXiamen UniversityXiamen 361005People’s Republic of China

As an electron-rich species,radical anions have a wide range of applications in organic *** addition,aromaticity is an essential concept in chemistry that has attracted considerable attention from experimentalists and... 详细信息

关键词： synthesis radical heterocyclic

Microstructure, mechanical and tribological properties of TiAl-based composites reinforced with high volume fraction of nearly network Ti_2AlC particulates

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Journal of Materials Science & Technology 2018年第4期34卷 670-678页

作者： jun Cheng Shengyu zhu Yuan Yu jun Yang Weimin Liu State Key Laboratory of Solid Lubrication Lanzhou Institute of Chemical PhysicsChinese Academy of Sciencestanzhou 730000China

TiAl-based composites reinforced with different high volume fractions of nearly network TizAIC phase have been successfully prepared by mechanical alloying and hot-pressing method. Their microstructure. mechanical and tribological properties have been investigated. Ti2AIC network becomes continuous but the network wall grows thicker with increasing the Ti2AIC content. The continuity and wall size of the network Ti2AIC phase exert a significant influence on the mechanical properties. The bending strength of the composites first increases and then decreases with the Ti2A1C content. The compressive strength of the composite decreases slightly compared to the TiAI alloy, but the hardness is enhanced. Due to the high hardness and load-carrying capacity of the network structure, these composites have the better wear resistance. And this enhancement is more notable at low applied loads and high Ti2A1C content. The mechanisms simulating the role of network Ti2AIC phase on the wear behavior and the wear process of TiAl/Ti2AIC composites at different applied loads have been proposed.

关键词： TiAl/Ti2AIC composites Network structure Wear resistance

Influences of traditional Chinese medicine intervention on the bone growth and metabolism of rats with simulated weightlessness

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Asian Pacific Journal of Tropical Medicine 2013年第3期6卷 224-227页

作者： jun zhu Department of Orthopaedics People's Hospital of Zhengzhou

Objective:To prohe into the influences of Chinese herbal compound on the growth and metabolism of weight-bearing bones of tail-suspended ***:Twenty-four male St) rats were randomly divided into blank conlrol group ***-suspended conlrol group(eight) and Chinese medicine treatment group leighti according to their *** treatment was done for the blank conlrol *** distilled water lavage was performed daily for the tail-suspended control *** the basis of the tail-suspended rat model,the rats were given Chinese herbal compound lavage every day in Chinese medicine treatment *** compound includes mulberry,Poria cocas and barbary *** lest cycle was four *** rats were killed after the *** right femoral bone was taken out for the physical measurements, and the left femoral bone was for the three-point beading *** influences of Chinese herbal compound on femoral hone growth and biomechanicsl properties of simulated weightlessness rats were ***:(1) After simulated weightlessness(tail-suspension),compared with the blank control group,all the physiological indexes of rat femoral bone decreased in tailsuspended group and Chinese medicine treatment group(P<0.05).The strength and rigidity of rat femoral bone decreased in tail-suspended group(P<0.01).the maximum load and rigidity coefficient also decreased with the inereasing toughness coefficient in the control group(P<0.01). i2i After the countermeasure of Chinese herbal compound,each biomcchanical indexes showed the tendency of increasing in Chinese medicine treatment group,and theses indexes were close to those of the blank control group(P<0.05),which indicated that(he bone loss caused by simulated weightlessness was ***:Chinese herbal compound for tonifying kidney could effectively prevent the bone loss and have some enhancements on the bone hiomechanical properties.

关键词： Chinese herbal compound Simulated weightlessness Rat femoral bone Biomechanical properties