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A meta-analysis of the impacts of forest logging on soil CO2 efflux

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Research in Cold and Arid Regions 2020年第3期12卷 165-179页

作者： LongFei Chen yangzhou Xiang ZhiBin He Jun Du PengFei Lin Xi Zhu Linze Inland River Basin Research Station Chinese Ecosystem Research NetworkKey Laboratory of Eco-hydrology of Inland River BasinNorthwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhouGansu 730000China School of Geography and Resources Guizhou Education UniversityGuiyangGuizhou 550018China

Soil CO2 efflux,the second largest flux in a forest carbon budget,plays an important role in global carbon *** logging is expected to have large effects on soil CO2 efflux and carbon sequestration in forest ***,a comprehensive understanding of soil CO2 efflux dynamics in response to forest logging remains elusive due to large variability in results obtained across individual ***,we used a meta-analysis approach to synthesize the results of 77 individual field studies to determine the impacts of forest logging on soil CO2 *** results reveal that forest logging significantly stimulated soil CO2 efflux of the growing season by 5.02%.However,averaged across all studies,nonsignificant effect was detected following forest *** large variation among forest logging impacts was best explained by forest type,logging type,and time since *** CO2 efflux in coniferous forests exhibited a significant increase(4.38%)due to forest logging,while mixed and hardwood forests showed no significant *** type also had a significant effect on soil CO2 efflux,with thinning increasing soil CO2 efflux by 12.05%,while clear-cutting decreasing soil CO2 efflux by 8.63%.The time since logging also had variable effects,with higher soil CO2 efflux for 2 years after logging,and lower for 3-6 years after logging;when exceeded 6 years,soil CO2 efflux *** significantly negative impacts of forest logging were detected on fine root biomass,the general positive effects on soil CO2 efflux can be explained by the accelerated decomposition of organic matter as a result of elevated soil temperature and organic substrate *** results demonstrate that forest logging had potentially negative effects on carbon sequestration in forest ecosystems.

关键词： soil respiration forest ecosystem thinning clear-cutting time since logging

Research on pharmacological mechanism of the treatment of Asthma by oral Bordetella pertussis

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沈阳药科大学学报 2008年第S1期25卷 115-116页

作者： CHI Shen,SUN Yun,ZHANG Bao-yuan(Medical College of yangzhou University,yangzhou 225001,China)

Objective To examine the effect of oral Bordetella pertussis on the asthma mice sensitized by ovalbumin(OVA),and explore the possible *** Culture the *** in Bordet-Gengou agar containing 25% rabbit *** the bacteria and inactive them at 80 ℃ for 30 min to get whole killed ***.32 BALB/C mice were randomly divided into control group,model-control group,model group and treatment *** mice were sensitized and challenged with OVA to establish asthma *** mice in treatment group were orally administrated with *** 7 days before *** mice in control group and model-control group were challenged with *** 24 hours of last challenge,bronchoaveolar lavage fluid(BALF)and peripheral blood were *** total cells and eosinophils were counted in *** Compared with the control group(2.03±0.42,0.33±0.82)×105 mL-1 and model-control group(2.16±0.48,0.16±0.41)×105 mL-1,the total cells(10.13±1.33)×105 mL-1 and eosinophils(11.83±4.573)×105 mL-1 in BALF were more in asthma mice(P<0.01).The number of total cells(5.50±1.55)×105 mL-1 and eosinophils(0.66±0.82)×105 mL-1 in BALF were reduced in asthma mice treated with *** compared with asthma mice(P<0.01).Conclusions Oral *** can inhabit airway inflammation of asthma mice and has the potential of treating asthma.

关键词： asthma airway inflammation Bordetella pertussis bral eosinophils

A System for Generating Operational Sketches Based on the Multi- level Graphic Library

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Journal of Systems Science and Systems Engineering 2001年第1期13卷 108-116页

作者： BAO Zhen qiang 1,2 , wang Ning sheng2 1.Institute of Technology, yangzhou University, yangzhou, Jiangsu 225009, China 2.Nanjing University of Aeronautics and Astronautics, Jiangsu 210016, China Institute of Technology Yangzhou University Yangzhou Jiangsu 225009 China Nanjing University of Aeronautics and Astronautics Jiangsu 210016 China Nanjing University of Aeronautics and Astronautics Jiangsu 210016 China

：This paper points out the limitations of both parametric and geometric model methodscommonly applied to generate operational sketches in CAPP. The ideas of multi-level graphic library areintroduced and a new generative method based on this library which combines parametric method withgeometric model method is presented. The principles and characteristics of the construction of the library aredescribed in detail and the feature data structure corresponding with the library is also presented.

关键词： generation of operational sketches feature library graphic library

DARZENS REACTION OF 2-CHLOROMETHYLBENZOXALINE

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Chinese Chemical Letters 1991年第7期2卷 515-516页

作者： Chao Guo YAN Wen Xing LU Ji Tao WU (Dept.of Chem.,yangzhou Teachers College,yangzhou,225002)

2-chloromethylbenzoxaline reacted with aromatic aldehydes in alkaline solution,giv- ing Darzens condensation product:2-aryl-3-benzoxalinyloxiranes.

关键词： DARZENS REACTION OF 2-CHLOROMETHYLBENZOXALINE

A　Study　on　Increasing　Economic　Benefit　of　a　State－owned　Enterprise　in　Liaoning　Province

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Systems Science and Systems Engineering 1995年第2期5卷 97-105页

作者： ZHANG Jiewei (Dalian University of Technology,Dalian,116024,China)FAN Jin(Institute of Technology of yangzhou University yangzhou,225001,China)

In this paper,Delphi method is used to study the reasons for lower economic benefit and plots for increasing economic benefit of a state-owned enterprise.

关键词： economic benefit Delphi method reasons plots.

A Review of Metal Silicides for Lithium-Ion Battery Anode Application

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Acta Metallurgica Sinica(English Letters) 2021年第3期34卷 291-308页

作者： Bo Ding Zhenfei Cai Zishan Ahsan yangzhou Ma Shihong Zhang Guangsheng Song Changzhou Yuan Weidong Yang Cuie Wen Key Laboratory of Green Fabrication and Surface Technology of Advanced Metal Materials Ministry of EducationSchool of Materials Science and EngineeringAnhui University of TechnologyMaanshan 243000China School of Materials Science and Engineering University of JinanJinan 250022China Future Manufacturing Flagship Commonwealth Science and Industries Research Organization(CSIRO)Melbourne.VIC 3168Australia School of Engineering RMIT University.MelbourneVIC 3001Australia Electronic Materials Research Laboratory Key Laboratory of the Ministry of EducationXi'an Jiaotong UniversityXi’an 710049China

Lithium batteries(LIBs) with low capacity graphite anode(~372 mAh g-1) cannot meet the ever-growing demand for new energy electric vehicles and renewable energy *** is essential to replace graphite anode with higher capacity anode materials for high-energy density ***(Si) is well known to be a possible alternative for graphite anode due to its highest capacity(~4200 mAh g-1).Unfortunately,large volume change during lithiation and delithiation has prevented the Si anode from being *** silicides are a promising type of anode materials which can improve cycling stability via the accommodation of volume change by dispersing Si in the metal inactive/active matrix,while maintain greater capacity than ***,we present a classification of Si alloying with metals in periodic table of elements,review the available literature on metal silicide anodes to outline the progress in improving and understanding the electrochemical performance of various metal silicides,analyze the challenges that remain in using metal silicides,and offer perspectives regarding their future research and development as anode materials for commercial LIBs application.

关键词： Li-ion battery Metal silicides Anode materials Electrochemical performance

A Parallel Algorithm for Solving Block-diagonal Structured Large Linear System

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Journal of Systems Science and Systems Engineering 2001年第2期13卷 191-196页

作者： SHEN Jie, ZHANG Zhong-lin, CHENG Ji-lin Department of Computer Science and Engineering, yangzhou University, yangzhou 225009, China Department of Computer Science and Engineering Yangzhou UniversityYangzhou 225009 China

A parallel algorithm for solving block-diagonal structured large linear system is presented. This algorithm is based on the ″gradient-simplex″ method. It partitions a large linear system into several small linear subsystems so that they can be solved in parallel. The algorithm has the merit of high speed and is suitable for the large linear systems with less coupling constrains. The efficiency and applicability of the method is also analyzed.

关键词： linear system parallel algorithm

Pollen Grain Germination and Pollen Tube Growth in Pistil of Rice

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Rice science 2008年第2期15卷 125-130页

作者： CHEN Shi-qiang wang Zhong LIU Man-xi XIE Zhao-wei wang Hui-hui Laboratory of Crop Inheritance Cultivation ＆ Physiology Yangzhou University Yangzhou 225009 China

The germination of pollen grain in vitro and the growth of pollen tube in the pistil of rice were observed with a microscope. The stigma was removed at different time points after pollination to study its effect on seed setting rate. The rice pollen grain started to germinate at 2 min after pollination and the pollen tube penetrated stigma into style in 5-10 min, 30 min later the end of pollen tube reached the bottom of ovary, and only some pollen tubes arrived at embryo sac at 40 min after pollination. Meanwhile, a small amount of callose began to deposit in the pollen tubes, a great deal of callose was observed at 50 min after pollination, whereas the pollen grain began to shrink. The growing rates of pollen tube in the rice stigma, style and ovary were 1500, 5000, and 5400 μm/h, respectively. The seed setting rate was quite low when the stigma was removed at about 10-15 min after pollination, gradually increased when it removed at 20 min to 50 min after pollination, and over 60% when it removed at 50 min after pollination and finally tended to be stable.

关键词： rice pollen grain germination pollen tube growth seed setting rate microscopic observation

A FACILE METHOD FOR DEBROMINATION OF VICINAL DIBROMIDES

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Chinese Chemical Letters 1991年第2期2卷 123-124页

作者： Qi ZHONG Jian Guo SHAO Chang Qing LIU Rong Jian LU Chemistry Department,yangzhou Teachers College,yangzhou,225002

In the presence of equimolar triethylamine,vicinal dibromides were found to be easily debrominated by dibutyl telluride,forming the co- rresponding olefins.

关键词： HSC A FACILE METHOD FOR DEBROMINATION OF VICINAL DIBROMIDES