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Leaf physiological and anatomical responses of two sympatric Paphiopedilum species to temperature

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Plant Diversity 2022年第1期44卷 101-108页

作者： jing-Qiu Feng Ji-Hua Wang Shi-bao Zhang Key Laboratory of Economic Plants and Biotechnology Yunnan Key Laboratory for Wild Plant ResourcesKunming Institute of BotanyChinese Academy of SciencesKunming650201YunnanChina University of Chinese Academy of Sciences Beijing100049China Flower Research Institute of Yunnan Academy of Agricultural Sciences Kunming650205YunnanChina

Paphiopedilum dianthum and *** are two endangered orchid species,with high ornamental and conservation *** are sympatric species,but their leaf anatomical traits and flowering period have significant ***,it is unclear whether the differences in leaf structure of the two species will affect their adaptabilities to ***,we investigated the leaf photosynthetic,anatomical,and flowering traits of these two species at three sites with different temperatures(Kunming,16.7±0.2°C;Puer,17.7±0.2°C;Menglun,23.3±0.2°C)in southwest *** with those at Puer and Kunming,the values of light-saturated photosynthetic rate(Pmax).stomatai conductance(gs),leaf thickness(LT),and stomatai density(SD)in both species were lower at *** values of Pmax,gs,仃,adaxial cuticle thickness(CTad)and SD in *** were higher than those of *** at the three *** with ***,there were no flowering plants of *** at *** results indicated that both species were less resistance to high temperature,and *** had a stronger adaptability to high-temperature than *** findings can provide valuable information for the conservation and cultivation of Paphiopedilum species.

关键词： Conservation Cultivation High-temperature Leaf anatomy Paphiopedilum Photosynthesis

f and g series solutions to a post-Newtonian two-body problem with parameters β and γ

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Research in Astronomy and Astrophysics 2016年第1期16卷 135-144页

作者： Song-He Qin jing-Xi Liu ze-Hao Zhong Yi Xie School of Astronomy and Space Science Nanjing University Nanjing 210093 China Shanghai Key Laboratory of Space Navigation and Position Techniques Shanghai 200030 China Key Laboratory of Modern Astronomy and Astrophysics Nanjing University Ministry of Education Nanjing 210093 China

Classical Newtonian f and g series for a Keplerian two-body problem are extended for the case of a post-Newtonian two-body problem with parameters β and γ. These two parameters are introduced to parameterize the post-Newtonian approximation of alternative theories of gravity and they are both equal to1 in general relativity. Up to the order of 30, we obtain all of the coefficients of the series in their exact forms without any cutoff for significant figures. The f and g series for the post-Newtonian two-body problem are also compared with a Runge-Kutta order 7 integrator. Although the f and g series have no superiority in terms of accuracy or efficiency at the order of 7, the discrepancy in the performances of these two methods is not quite distinct. However, the f and g series have the advantage of flexibility for going to higher *** examples of relativistic advance of periastron are given and the effect of gravitational radiation on the scheme of f and g series is evaluated.

关键词： gravitation - celestial mechanics - binaries: general

Intelligent casting:Empowering the future foundry industry

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China Foundry 2024年第5期21卷 409-426页

作者： Jin-wu Kang bao-lin Liu Tao jing Hou-fa Shen School of Materials Science and Engineering Key Laboratory for Advanced Materials Processing TechnologyTsinghua UniversityBeijing 100084China

Emerging technological advances are reshaping the casting sector in latest *** technology is evolving towards intelligent casting paradigm that involves automation,greenization and intelligentization,which attracts more and more attention from the academic and industry *** this paper,the main features of casting technology were briefly summarized and forecasted,and the recent developments of key technologies and the innovative efforts made in promoting intelligent casting process were ***,the technical visions of intelligent casting process were also put *** key technologies for intelligent casting process comprise 3D printing technologies,intelligent mold technologies and intelligent process control *** future,the intelligent mold that derived from mold with sensors,control devices and actuators will probably incorporate the Internet of Things,online inspection,embedded simulation,decision-making and control system,and other technologies to form intelligent cyber-physical casting system,which may pave the way to realize intelligent *** is promising that the intelligent casting process will eventually achieve the goal of real-time process optimization and full-scale control,with the defects,microstructure,performance,and service life of the fabricated castings can be accurately predicted and tailored.

关键词： intelligent casting 3D printing intelligent mold process control cyber-physical casting system embedded simulation

Occurrence and characteristics of sporadic K layer observed by lidar over Beijing, China

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Science China Earth Sciences 2016年第3期59卷 540-547页

作者： JIAO jing YANG Guo Tao WANG Ji Hong WANG ze Long YANG Yong State Key Laboratory of Space Weather Center for Space Science and Applied Research Chinese Academy of Sciences College of Earth Science University of Chinese Academy of Sciences Wuhan Institute of Physics and Mathematics Chinese Academy of Sciences

A double-laser-beam lidar was successfully developed in 2010 to measure the K layer over Yanqing County, Beijing(40.5°N, 116.2°E). Comprehensive statistical analyses of sporadic K(Ks) layer parameters were conducted using two years of lidar data, and the parameters of the Ks layers and their distribution obtained by the analyses are described. The seasonal distribution of Ks occurrence was obtained, with two maxima observed in January and July, respectively. The seasonal distributions of sporadic E(Es) occurrence over Beijing differ from those of Ks occurrence. However, good correlations between Es and Ks in case by case study were found. We also found that four Ks events with peak altitudes lower than 90 km were associated with large and sharp temperature increases in five comparative examples.

关键词： Sporadic K layer Lidar observation Sporadic E layer Atmospheric temperature

Molecular Mapping of a Stripe Rust Resistance Gene YrH9020a Transferred from Psathyrostachys huashanica Keng on Wheat Chromosome 6D

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Journal of Integrative Agriculture 2014年第12期13卷 2577-2583页

作者： LIU ze-guang YAO Wei-yuan SHEN Xue-xue CHAO Kai-xiang FAN Yu LI Min-zhou WANG bao-tong LI Qiang jing Jin-xue State Key Laboratory of Crop Stress Biology for Arid Areas College of Plant Protection Northwest A&F University

Stripe rust （yellow rust）, caused by Puccinia striiformis f. sp. tritici （Pst）, is one of the most devastating diseases of wheat throughout the world. H9020-1-6-8-3 is a translocation line originally developed from interspeciifc hybridization between wheat line 7182 and Psathyrostachys huashanica Keng and is resistant to most Pst races in China. To identify the resistance gene（s） in the translocation line, H9020-1-6-8-3 was crossed with susceptible cultivar Mingxian 169, and seedlings of the parents, F1, F2, F3, and BC1 generations were tested with prevalent Chinese Pst race CYR32 under controlled greenhouse conditions. The results indicated that there is a single dominant gene, temporarily designated as YrH9020a, conferring resistance to CYR32. The resistance gene was mapped by the F2 population from Mingxian 169/H9020-1-6-8-3. It was linked to six microsatellite markers, including Xbarc196, Xbarc202, Xbarc96, Xgpw4372, Xbarc21, and Xgdm141, lfanked by Xbarc96 and Xbarc202 with at 4.5 and 8.3 cM, respectively. Based on the chromosomal locations of these markers and the test of Chinese Spring （CS） nullitetrasomic and ditelosomic lines, the gene was assigned to chromosome 6D. According to the origin and the chromosomal location, YrH9020a might be a new resistance gene to stripe rust. The lfanking markers linked to YrH9020a could be useful for marker-assisted selection in breeding programs.

关键词： Puccinia striiformis f. sp. tritici Psathyrostachys huashanica Keng resistance gene genetic analysis SSR markers

Melting and Annealing Peak Temperatures of Poly(butylene succinate) on the Same Hoffman-Weeks Plot Parallel to Tm=Tc Line

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Chinese Journal of Polymer Science 2021年第6期39卷 745-755,I0007页

作者： Zhi-Ning Xie Hai-Mu Ye Tong Chen Tian-ze Zheng Jun Xu bao-Hua Guo Advanced Materials Laboratory Department of Chemical EngineeringTsinghua UniversityBeijing 100084China Departmentof Materials Science and Engineering College of New Energy and MaterialsChina University of PetroleumBeijing 102249China

The crystallization and melting behavior of polymers is of theoretical *** this work,poly(butylene succinate)(PBS)was selected as an example to study such behavior at low supercooling via introduction of the extended-chain crystal(ECC)of the same polymer as nucleating *** crystallization of PBS with its ECC as nucleating agent in a wide temperature range(90–127°C)and the following melting behavior were *** is revealed that the melting point(Tm',for Tc≥113°C)and the annealing peak temperature(Ta',for Tc=90–100°C)show similar asymptotic *** Tm and Ta approach to a value of ca.3.3°C higher than the corresponding Tc when the crystallization time tc approaches the starting *** is to say,the Hoffman-Weeks plot is parallel to Tm=Tc *** crystallization line became parallel to the melting line when PBS was crystallized at Tc higher than 102°*** on these results,we propose that the parallel relationship and the intrinsic similarity between the Ta and the Tm observed at the two ends of the Tc range could be attributed to the metastable crystals formed at the beginning of crystallization.

关键词： Polymer crystallization Melting temperature Hoffman-Weeks plot Stabilization mechanism Baby crystal

Mechanisms of Acupuncture in Improving Alzheimer's Disease Caused by Mitochondrial Damage

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Chinese Journal of Integrative Medicine 2022年第3期28卷 272-280页

作者： JIANG Yu-hang HE Jia-kai LI Ran CHEN ze-hao JIA bao-hui Department of Acupuncture Guang'anmen HospitalChina Academy of Chinese Medical SciencesBeijing(100053)China

Alzheimer's disease(AD)is one of the most common neurodegenerative diseases among the elderly and it accounts for nearly 80%of all *** pathogenesis of AD is complicated and enigmatic thus *** mitochondrial cascade hypothesis assumes that mitochondrial damage may mediate,drive,or contribute to a variety of AD pathologies and may be the main factor in late-onset ***,there are no widely recognized drugs able to attenuate mitochondrial damage in ***,increasing evidence supports the efficacy of acupuncture for improving the mitochondrial structure and protecting mitochondrial functions in *** review reports the mechanisms by which acupuncture regulates mitochondrial dynamics,energy metabolism,calcium homeostasis and *** conclusion,these findings suggest that AD mitochondrial dysfunction represents a reasonable therapeutic target and acupuncture could play a significant role in preventing and treating AD.

关键词： acupuncture Alzheimer's disease mitochondrial damage review

Effects of acid-rock reaction on physical properties during CO_(2)-rich industrial waste gas(CO_(2)-rich IWG)injection in shale reservoirs

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Petroleum Science 2024年第1期21卷 272-285页

作者： Yi-Fan Wang jing Wang Hui-Qing Liu Xiao-Cong Lv ze-Min Ji National Key Laboratory of Petroleum Resources and Engineering China University of PetroleumBeijing102249China MOE Key Laboratory of Petroleum Engineering China University of PetroleumBeijing102249China Research Institute of Exploration and Development PetroChinaBeijing100083China

"Carbon peaking and carbon neutrality"is an essential national strategy,and the geological storage and utilization of CO_(2)is a hot issue ***,due to the scarcity of pure CO_(2)gas sources in China and the high cost of CO_(2)capture,CO_(2)-rich industrial waste gas(CO_(2)-rich IWG)is gradually emerging into the public's ***_(2)has good adsorption properties on shale surfaces,but acidic gases can react with shale,so the mechanism of the CO_(2)-rich IWG-water-shale reaction and the change in reservoir properties will determine the stability of geological ***,based on the mineral composition of the Longmaxi Formation shale,this study constructs a thermodynamic equilibrium model of water-rock reactions and simulates the regularity of reactions between CO_(2)-rich IWG and shale *** results indicate that CO_(2)consumed 12%after reaction,and impurity gases in the CO_(2)-rich IWG can be dissolved entirely,thus demonstrating the feasibility of treating IWG through water-rock *** IWG inhibits the dissolution of CO_(2),the optimal composition of CO_(2)-rich IWG is 95%CO_(2)and 5%IWG when CO_(2)geological storage is the main *** contrast,when the main goal is the geological storage of total CO_(2)-rich IWG or impurity gas,the optimal CO_(2)-rich IWG composition is 50%CO_(2)and 50%*** the CO_(2)-rich IWG-water-shale reaction,temperature has less influence on the water-rock reaction,while pressure is the most important ***2 has the greatest impact on water-rock reaction in *** minerals,clay minerals such as illite and montmorillonite had a significant effect on water-rock *** overall reaction is dominated by precipitation and the volume of the rock skeleton has increased by 0.74 cm3,resulting in a decrease in shale porosity,which enhances the stability of CO_(2)geological storage to some *** the reaction between CO_(2)-rich IWG-water-shale at simulated temperatures and pressures,precipitation

关键词： CO_(2)-rich industrial waste gas Geological storage Acid-rock reaction Shale Geochemical modelling

Microstructure and mechanical properties of Al-5.5Fe-1.1V-0.6Si alloy solidified under near-rapid cooling and with Ce addition

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Rare Metals 2018年第12期37卷 1070-1075页

作者： Yu-Lin Liu Lei Luo Ming-ze Shun Li Zhang Yu-Hua Zhao bao-Lin Wu Liaoning Provincial Key Laboratory of Light Alloys and Processing Technology School of Materials Science and Engineering Shenyang Aerospace University

Al-Fe-V-Si alloys were developed for use at elevated temperature and usually produced through a rapid solidification-powder metallurgy route. In this work, effort was made to produce the material via casting route. The studied alloys were cast under the condition of near-rapid cooling. The influence of Ce addition on microstructure and mechanical properties of near-rapid solidified alloys were investigated. The results indicate that the as-cast microstructure of Al-5.5 Fe-1.1 V-0.6 Si alloy is significantly refined when the alloy was solidified under nearrapid cooling. Adding Ce results in the further refinement of intermetallic compound and the formation of an Al-V-Ce phase which replaces the primary phase Al(Fe,V)Si. The mechanical properties of the alloy are significantly improved by Ce addition: More than 70% increase in tensile strength and elongation is achieved by adding 1.00 wt% Ce to the alloy. It is concluded that near-rapid cooling and Ce addition are effective in improving mechanical properties of cast Al-5.5 Fe-1.1 V-0.6 Si alloy.

关键词： Aluminum alloys Al-Fe-V-Si alloy Rapid solidification Solidification microstructures Mechanical properties