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Paleotopographic controls on modern gully evolution in the loess landforms of China

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Science China Earth Sciences 2017年第3期60卷 438-451页

作者： xiong LiYang TANG GuoAn zhu A-xing YUAN BaoYin LU BinYing DANG TianMin Key Laboratory of Virtual Geographic Environment Ministry of EducationNanjing Normal UniversityNanjing 210023China State Key Laboratory Cultivation Base of Geographical Environment Evolution of Jiangsu Province Nanjing 210023China Jiangsu Center for Collaborative Innovation in Geographical Information Resource Development and Application Nanjing 210023China Department of Geography University of Wisconsin-MadisonMadison 53706USA Institute of Geology and Geophysics Chinese Academy of Sciences Beijing 100029 China Highway Survey and Design Institute of Shaanxi Province Xi'an 710068China College of Resources and Environment Northwest Agriculture and Forest UniversityYangling 712100China

The inhomogeneous and non-flat paleotopography in a depositional landform area profoundly controls the process of modem gully evolution and shapes the structure of a gully network. However, this controlling effect of paleotopography on modem gully evolution is mostly ignored because of the difficulties in paleotopography reconstruction. In this study, loess area in China is selected as case area for its typical depositional landform area and inhomogeneous and non-flat paleotopography during the Quaternary. The paleotopography underlying loess is considered while evaluating its controlling effects on the gully evolutionary process. On the basis of the geophysical prospecting, detailed geological information, and high-resolution digital elevation model, we reconstruct the pre-Quaternary paleotopographic surface in the case area. Comparative analysis is conducted to reveal the modern gully evolution in relation to the paleotopography. Results show that the concave area of the paleotopography acts as the basement of the high-order modern gully evolution in the hilly-gully area, although this concave area can be covered and buried by the loess depositional process during the Quaternary. A significant controlling effect of paleotopography on high-order modern gully evolution can be observed in a depositional landform with a hilly-gully underlying topography, whereas a relatively weak controlling effect exists in a flat underlying topograpnlcal area oecause of the strong horizontal shift effect of gully formation process. Several low-order modern gullies also exist and limit the controlling effect of paleotopography. These results reveal a controlled high-order modern gully evolutionary process and a rather dynamic low-order modem gully evolutionary process in the hilly-gully area. These results also help us understand the variations in different modern gully evolution in relation to paleotopography and the different management schemes for soil conservation and ecological

关键词： Paleotopography Gully evolution Controlling effect Loess landform

Effect of yttrium treatment on alumina inclusions in high carbon steel

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Journal of Iron and Steel Research International 2022年第4期29卷 655-664页

作者： Yi Wang Chang-rong Li Lin-zhu Wang xing-qiang xiong Lu Chen School of Materials and Metallurgy Guizhou UniversityGuiyang 550025GuizhouChina Guizhou Key Laboratory of Metallurgical Engineering and Process Energy Conservation Guiyang 550025GuizhouChina

Aluminum oxide inclusions in SWRS82B steel seriously affect the drawing performance of steel *** effects of different addition amounts of yttrium(within the range of 0%–0.026%)on the composition,morphology,size and spacing of aluminum oxide inclusions were studied by scanning electron microscopy and energy spectrum *** on classical thermodynamics and FactSage software,the predominance diagram of inclusions in Fe–O–S–Y system and the effect of the addition of rare earth yttrium on the stability of alumina inclusions were *** results showed that molten steel was modified by adding the rare earth element *** can be inferred that the approximate route of target inclusion modification was:Al_(2)O_(3)→Y_(2)S_(3)+YAlO_(3)+Al_(2)O_(3)→Y_(2)S_(3)+YAlO_(3)+Y_(2)O_(2)S+YAlO_(3)+Al_(2)O_(3)→Y_(2)S_(3)+Y_(2)O_(2)*** experimental samples with 0.026%added yttrium had the best inclusion characteristics,in which the inclusion surface density distribution was uniform,and the interfacial distance between inclusions was mainly in the range of 100–500μ*** modification,the average inclusion size in molten steel was reduced by 6.9–8.6μ*** mechanism of yttrium modification was discussed based on actual calculation results and experimental results.

关键词： Yttrium treatment Modification of aluminum inclusions Inclusion evolution Thermodynamics

Failure behavior and strength model of blocky rock mass with and without rockbolts

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International Journal of Mining Science and Technology 2024年第6期34卷 747-762页

作者： Chun zhu Xiansen xing Manchao He Zhicheng Tang Feng xiong Zuyang Ye Chaoshui Xu School of Earth Sciences and Engineering Hohai UniversityNanjing 210024China Key Laboratory of Water Management and Water Security for Yellow River Basin Ministry of Water Resources(under construction)Zhengzhou 450003China State Key Laboratory for Geomechanics&Deep Underground Engineering China University of Mining and TechnologyBeijing 10083China Faculty of Engineering China University of GeosciencesWuhan 430074China State Key Laboratory of Geomechanics and Geotechnical Engineering Institute of Rock and Soil MechanicsChinese Academy of SciencesWuhan 430071China School of Resource and Environmental Engineering Wuhan University of Science and TechnologyWuhan 430081China School of Chemical Engineering Faculty of SciencesEngineering and TechnologyThe University of AdelaideAdeliade 5005Australia

To better understand the failure behaviours and strength of bolt-reinforced blocky rocks,large scale extensive laboratory experiments are carried out on blocky rock-like specimens with and without rockbolt *** results show that both shear failure and tensile failure along joint surfaces are observed but the shear failure is a main controlling factor for the peak strength of the rock mass with and without *** rockbolts are necked and shear deformation simultaneously happens in bolt reinforced rock *** the joint dip angle increases,the joint shear failure becomes more *** number of rockbolts has a significant impact on the peak strain and uniaxial compressive strength(UCS),but little influence on the deformation modulus of the rock *** the Winkler beam model to represent the rockbolt behaviours,an analytical model for the prediction of the strength of boltreinforced blocky rocks is *** agreement between the UCS values predicted by proposed model and obtained from experiments suggest an encouraging performance of the proposed *** addition,the performance of the proposed model is further assessed using published results in the literature,indicating the proposed model can be used effectively in the prediction of UCS of bolt-reinforced blocky rocks.

关键词： Blocky rock mass Rockbolt ground support Uniaxial compression test Failure mechanism Uniaxial compressive strength model

Electrospray Ionization Mass Spectra of Amino Acid Methyl Ester 5′-Phosphoramidates of 2′,3′-Isopropylideneuridine

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Chemical Research in Chinese Universities 2006年第6期22卷 732-737页

作者： CHEN Wei-zhu GAO Yu-xing BAI Yong-gang HAN Da-xiong ZHAO Yu-fen The Key Laboratory for Chemical Biology of Fujian Province Department of Chemistry College of Chemistry and Chemical Engineering Xiamen University Xiamen 361005 P. R. China Key Laboratory for Bioorganic Phosphorus Chemistry of the Ministry of Education Department of Chemistry School of Life Sciences and Engineering Tsinghua University Beijin 100084 P. R. China The Third Institute of Oceanography of the State Oceanic Administration Xiamen 361005 P. R. China

Amino acid methyl ester phosphates were synthesized and determined by using positive-ion mode dectrospmy ionization mass spectrometry（ESIMS） in combination with multistage tandem mass spectrometry. The fragmentation pathways were investigated, and it was observed that most fragment ions contained the phosphoryl group. It was interesting to observe that the fragmentation pathways of the protonated molecule show some differences when compared with those of the sodium ion adduct. The methoxy group of amino acid methyl ester can migrate from the carbonyl group to the phosphoryl group in the sodium ion adduct.

关键词： ESIMS Fragmentation pathway Methoxy group rearrangement Pentacoordinated phosphorus intermediate Amino acid methyl ester 5'-phosphoramidate of nucleoside

Light-controlled soft bio-microrobot

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Light(Science & Applications) 2024年第3期13卷 531-543页

作者： Jianyun xiong xing Li Ziyi He Yang Shi Ting Pan Guoshuai zhu Dengyun Lu Hongbao Xin Guangdong Provincial Key Laboratory of Nanophotonic Manipulation Institute of NanophotonicsJinan University511443 GuangzhouChina

Micro/nanorobots hold exciting prospects for biomedical and even clinical applications due to their small size and high ***,it is still a big challenge to maneuver micro/nanorobots into narrow spaces with high deformability and adaptability to perform complicated biomedical ***,we report a light-controlled soft bio-microrobots(called“Ebot”)based on Euglena gracilis that are capable of performing multiple tasks in narrow microenvironments including intestinal mucosa with high controllability,deformability and *** motion of the Ebot can be precisely navigated via light-controlled polygonal flagellum ***,the Ebot shows highly controlled deformability with different light illumination duration,which allows it to pass through narrow and curved microchannels with high *** these features,Ebots are able to execute multiple tasks,such as targeted drug delivery,selective removal of diseased cells in intestinal mucosa,as well as photodynamic *** light-controlled Ebot provides a new bio-microrobotic tool,with many new possibilities for biomedical task execution in narrow and complicated spaces where conventional tools are difficult to access due to the lack of deformability and bio-adaptability.

关键词： narrow illumination curved

Effects of mummy consumption on fitness and oviposition site selection on Harmonia axyridis

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Insect Science 2020年第5期27卷 1101-1110页

作者： xing-Lin Yu Yi Feng zhu-Jun Feng Phongsakorn Chana Guan-xiong zhu Peng-Liang Xia Tong-Xian Liu Key Laboratory of Integrated Pest Management on Crops in Northwestern Loess Plateau of Ministry of Agriculture College of Plant ProtectionNorthwest A&F UniversityYanglingShaanxiChina Hubei Tobacco Company Enshi State Co. Ltd.EnshiHubeiChin

Intraguild predation(IGP)has been commonly reported between predators and parasitoids used as biological control agents as predators consuming parasitoids within their ***,the effect of parasitoid-mummy consumption on the fitness of the predator and subsequent oviposition site selection have not been well *** our study,we conducted two laboratory experiments to examine the influence of Aphidius gifuen-sis Ashmead(Hymenoptera:Braconidae)mummies as prey on fitness and subsequently oviposition site selection of Harmonia axyridis(Pallas)(Coleoptera:Coccnellidae).Re-sults indicate that when *** was reared on *** mummies only,its larval development was prolonged,and body weight of the 4th instar larvae and newly emerged adults,and fecundity ***,*** did not exhibit oviposition pref-erence on plants infested with unparasitized aphids or aphids parasitized for shorter than 9 ***,compared with plants with mummies(parasitized≥9 days),*** laid more eggs on plants with unparasitized *** contrast,*** previously fed with *** mummies did not show a significant oviposition preference between plants with unparasitized aphids and those with mummies(parasitized≥9 days).Overall,our results suggest that mummy consumption reduced the fitness of *** *** avoided laying eggs on plants with *** mummies,prior feeding ex-perience on *** mummies could alter the oviposition site ***,in biological control practice,prior feeding experience of *** should be carflly considered for reduction of IGP and increase of fitness of *** on ***.

关键词： Aphidius gifuensis feeding experience fitness intraguild predation Myzus persicae oviposition site selection

Nitrous Oxide and Methane Emissions as Affected by Water,Soil and Nitrogen

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Pedosphere 2007年第2期17卷 146-155页

作者： xiong Zheng-Qin xing Guang-Xi zhu Zhao-Liang State Key Laboratory of Soil and Sustainable Agriculture Institute of Soil Science Chinese Academy of Sciences Nanjing 210008 （China）. Department of Physics Portland State University Portland Oregon 97207 （USA）

Specific management of water regimes, soil and N in China might play an important role in regulating N2O and CH4 emissions in rice fields. Nitrous oxide and methane emissions from alternate non-flooded/flooded paddies were monitored simultaneously during a 516-day incubation with lysimeter experiments. Two N sources (15N-(NH4)2SO4 and 15N-labeled milk vetch) were applied to two contrasting paddies: one derived from Xiashu loess (Loess) and one from Quaternary red clay (Clay). Both N2O and CH4 emissions were significantly higher in soil Clay than in soil Loess during the flooded period. For both soil, N2O emissions peaked at the transition periods shortly after the beginning of the flooded and non-flooded seasons. Soil type affected N2O emission patterns. In soil Clay, the emission peak during the transition period from non-flooded to flooded conditions was much higher than the peak during the transition period from flooded to non-flooded conditions. In soil Loess, the emission peak during the transition period from flooded to non-flooded conditions was obviously higher than the peak during the transition period from non-flooded to flooded conditions except for milk vetch treatment. Soil type also had a significant effect on CH4 emissions during the flooded season, over which the weighted average flux was 111 mg C m-2 h-1 and 2.2 mg C m-2 h-1 from Clay and Loess, respectively. Results indicated that it was the transition in the water regime that dominated N2O emissions while it was the soil type that dominated CH4 emissions during the flooded season. Anaerobic oxidation of methane possibly existed in soil Loess during the flooded season.

关键词： anaerobic oxidation of methane (AOM) dissimilatory nitrate reduction to ammonium (DNRA) greenhouse gasses lysimeter paddy soil

Mature mediastinal bronchogenic cyst with left pericardial defect: A case report

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World Journal of Clinical Cases 2021年第36期9卷 11362-11368页

作者： Xiao zhu Lei Zhang Zhen Tang Fu-Bao xing xiong Gao Wen-Bang Chen Department of Cardiothoracic Surgery The First Affiliated Hospital of Bengbu Medical CollegeBengbu 233004Anhui ProvinceChina

BACKGROUND Mediastinal bronchogenic cysts and pericardial defects are both *** is extremely rare that both occur *** the best of our knowledge,this is the first case of a coexistent bronchogenic cyst and pericardial defect reported in *** performed a literature review and found a relationship between bronchogenic cysts and pericardial defects,which further revealed the correlation between the bronchus and pericardium during embryonic *** SUMMARY A 14-year-old boy attended a local hospital for ankylosing *** radiography showed an enhanced circular-density shadow near the left *** patient had no chest symptoms and the physical examination was *** of the mediastinal occupation,the patient visited our department of chest surgery for further *** surgery,a left pericardial defect was *** bronchogenic cyst was removed by thoracoscopic surgery,but the pericardial defect remained untreated,and a satisfactory outcome was achieved after the *** patient was diagnosed with a mediastinal *** pathological diagnosis of the tumor was a bronchogenic *** This case further reveals the correlation between the bronchus and pericardium during embryonic development.

关键词： Bronchogenic cyst Pericardial defect Mediastinal mass Embryonic development Literature review Case report

Composition of stable isotope in precipitation and its influences by different vapor sources in the eastern Qilian Mountains

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Journal of Mountain Science 2018年第10期15卷 2207-2217页

作者： JIA Wen-xiong MA xing-gang XU Xiu-ting YUAN Rui-feng DING Dan zhu Guo-feng College of Geography and Environmental Science Northwest Normal UniversityLanzhou 730070China State Key Laboratory of Cryosphere Sciences Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou 73ooooChina

To better understand the process of precipitation and water cycle, the composition of stable isotope in precipitation and its influences by different vapor sources in the eastern of Qilian Mountains were conducted from June 2013 to May 2014. The total of 100 precipitation samples were collected in Wushaoling national meteorological station located in the eastern of Qilian Mountains. The analysis indicates that the slope of Local Meteoric Water Line is lower than that of Global Meteoric Water Line. The average values of δ18 O and δD in precipitation are higher in summer but lower in winter. Except for negative correlation with relative humidity, the stable isotope values in precipitation are positive correlations with temperature, precipitation and water vapor pressure. Influenced by water vapor source, the values of d-excess are lower for the Westerly wind and the South Asia Monsoon onJuly and the Westerly wind and the East Asia Monsoon on August, but they are higher for the Westerly wind on other months, that they are also influenced by the weather conditions in rainfall process. The variation of stable isotope in precipitation exhibited significant temperature effect, and there is also some precipitation amount effect in spring and summer.

关键词： Stable isotope Precipitation Water vapor source Qilian Mountains