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Wuhan University Journal of Natural Sciences 2008年第3期13卷 324-330页

作者： zhang hong gao linan Faculty of Geography Recourses Sciences Sichuan NormalUniversity Chengdu 610066 Sichuan China

This article, by combining field investigation with laboratorial analysis, studies diverse alpine meadow at the Eastern Margin of the Qinghai-Tibet Plateau for the underground biomass dynamics, vertical distribution of the content of soil carbon and nitrogen, the connection between the biomass and the content of carbon and nitrogen. The studies show that underground biomass in the herb layer of upland meadow is more than that in the terrace meadow, while underground biomass in the upland shrubland is the most. The vertical distribution of underground biomass of each type is obvious as in shape of＂T＂. As to the distribution of the content of soil organic carbon in the three sample grounds, it showed that the deeper the soil the less the content of soil organic carbon. In May, unlike at terrace meadow, the underground biomass and the content of soil organic carbon in positive proportion, such revelation at upland meadow and upland shrubland is not apparent. In July, at upland meadow and terrace meadow the underground biomass and the content of soil total nitrogen in positive proportion, such revelation at upland shrubland is not apparent either.

关键词： alpine meadow underground biomass soil organic carbon: soil total nitrogen: soil avail nitrogen

Effect of oxide inclusions on MnS precipitates and tensile mechanical property of high-strength low-alloy steel

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Journal of Iron and Steel Research International 2024年第5期31卷 1210-1220页

作者： Xiao-yong gao hong Wei Li-feng zhang School of Mechanical Engineering Yanshan UniversityQinhuangdao066004HebeiChina School of Materials Science and Engineering Yanshan UniversityQinhuangdao066004HebeiChina School of Mechanical and Materials Engineering North China University of TechnologyBeijing100144China

The key role of oxide inclusions on the microstructure and mechanical property of a high-strength low-alloy steel was *** field emission scanning electron microscope equipped with energy-dispersive spectrometry was used to characterize MnS *** inclusions play an important role in the shape control of MnS *** oxides fovored to decrease the size and the aspect ratio of MnS *** less oxide inclusions in the steel,approximately over 16.7%MnS precipitates were with aspect ratio a>5 and pure MnS precipitates accounted for 75.9%in ***,with more oxide inclusions in the steel,only 7.4%MnS precipitates were with a>5 and pure MnS precipitates accounted for 60.1%in *** of MnS by oxide inclusions improved the strength and inhibited the *** oxide inclusions in the steel increased the yield strength and tensile strength of the steel in both longitudinal and transverse directions,and lowered the anisotropy of the mechanical property.

关键词： High-strength low-alloy steel MnS Oxide inclusion Mechanical property Anisotropy

Research on ozone formation sensitivity based on observational methods:Development history,methodology,and application and prospects in China

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Journal of Environmental Sciences 2024年第4期138卷 543-560页

作者： Wanghui Chu hong Li Yuanyuan Ji Xin zhang Likun Xue Jian gao Cong An State Key Laboratory of Environmental Criteria and Risk Assessment Chinese Research Academy of Environmental SciencesBeijing 100012China Environment Research Institute Shandong UniversityQingdao 266237China

Observation-based method for O_(3)formation sensitivity research is an important tool to analyze the causes of ground-level O_(3)pollution,which has broad application potentials in determining the O_(3)pollution formation mechanism and developing prevention and control *** paper outlined the development history of research on O_(3)formation sensitivity based on observational methods,described the principle and applicability of the methodology,summarized the relative application results in China and provided recommendations on the prevention and control of O_(3)pollution in China based on relevant study results,and finally pointed out the shortcomings and future development prospects in this field in *** overview study showed that the O_(3)formation sensitivity in some urban areas in China in recent years presented a gradual shifting tendency from the VOC-limited regime to the transition regime or the NO_(x)-limited regime due to the implementation of the O_(3)precursors emission reduction policies;O_(3)pollution control strategies and precursor control countermeasures should be formulated based on local conditions and the dynamic control capability of O_(3)pollution control measures should be *** are still some current deficiencies in the study field in ***,it is recommended that a stereoscopic monitoring network for atmospheric photochemical components should be further constructed and improved;the atmospheric chemical mechanisms should be vigorously developed,and standardized methods for determining the O_(3)formation sensitivity should be established in China in the near future.

关键词： Observation-based method Ozone formation sensitivity Ozone pollution prevention and control VOCs NO_(x) OBM

An innovative classification system for ranking the biological effects of marine aromatic hydrocarbons based on fish embryotoxicity

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Acta Oceanologica Sinica 2024年第6期43卷 153-162页

作者： Ronghui Zheng Chao Fang Fukun hong Min zhang Fulong gao Yusheng zhang Jun Bo Key Laboratory of Marine Ecological Conservation and Restoration Third Institute of OceanographyMinistry of Natural ResourcesXiamen 361005China Observation and Research Station of Coastal Wetland Ecosystem in Beibu Gulf Ministry of Natural ResourcesBeihai 536015China

Petroleum hydrocarbon pollution is a global concern,particularly in coastal *** aromatic hydrocarbons(PAHs) are regarded as the most toxic components of petroleum *** this study,the biomonitoring and ranking effects of petroleum hydrocarbons and PAHs on the marine fish model Oryzias melastigma embryos were determined in the Jiulong River Estuary(JRE) and its adjacent waters in *** results showed that the levels of petroleum hydrocarbons from almost all sites met the primary standard for marine seawater quality,and the concentrations of the 16 priority PAHs in the surface seawater were lower compared with those in other coastal areas worldwide.A new fish expert system based on the embryotoxicity of ***(OME-FES) was developed and applied in the field to evaluate the biological effects of petroleum hydrocarbons and *** selected physiological index and molecular indicators in OME-FES were appropriate biomarkers for indicating the harmful effects of petroleum hydrocarbons and *** outcome of OME-FES revealed that the biological effect levels of the sampling sites ranged from level Ⅰ(no stress) to level Ⅲ(medium stress),which is further corroborated by the findings of nested analysis of variance(ANOVA) *** results suggest that the OME-FES is an effective tool for evaluating and ranking the biological effects of marine petroleum hydrocarbons and *** method may also be applied to evaluate other marine pollutants based on its framework.

关键词： petroleum hydrocarbons polycyclic aromatic hydrocarbons fish expert system integrated biomarker response nested one-way analysis of variance

Quantitative method to predict the energetics of helium-nanocavities interactions in metal systems based on electrophobic interaction

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Journal of Materiomics 2024年第3期10卷 725-737页

作者： Fengping Luo Bowen zhang Zhiying gao Jia Huang hong-Bo Zhou Guang-hong Lu Fei gao Yugang Wang Chenxu Wang State Key Laboratory of Nuclear Physics and Technology Center for Applied Physics and TechnologyPeking UniversityBeijing100871China Department of Physics Beihang UniversityBeijing100191China Department of Nuclear Engineering and Radiological Science University of MichiganAnn ArborMI48109USA

Energetics of helium-nanocavities interactions are crucial for unveiling underlying mechanisms of nanocavity evolution in nuclear ***,it becomes intractable and even not feasible to obtain these energetics via atomic simulations with increasing nanocavity size and increasing helium content in ***,a universal scaling law of helium-induced interaction energies in nanocavities in metal systems is proposed based on electrophobic interaction of *** on this scaling law and ab-initio calculations,a predictive method for binding energies of helium and displacement defects to nanocavities of arbitrary sizes and with different helium/vacancy ratios is established for BCC iron as a representative and validated by atomic *** predictive method reveals that the critical helium/vacancy ratio for helium-enhanced vacancy binding to nanocavities in-creases with increasing nanocavity size,and the helium/vacancy ratio giving the highest stability of nanocavities is about *** Ostwald ripening of nanocavities is delayed by helium to higher temper-atures due to reduced vacancy de-trapping rates from *** proposed scaling law can be generalized to many metal systems studied in the nuclear materials *** readily coupled into mesoscale models of irradiation damages,this predictive method facilitates clarifying helium role in cavity swelling of metallic nuclear materials.

关键词： Nanocavities Helium Electrophobic interaction Predictive method

Noise-Tolerant ZNN-Based Data-Driven Iterative Learning Control for Discrete Nonaffine Nonlinear MIMO Repetitive Systems

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IEEE/CAA Journal of Automatica Sinica 2024年第2期11卷 344-361页

作者： Yunfeng Hu Chong zhang Bo Wang Jing Zhao Xun Gong Jinwu gao hong Chen State Key Laboratory of Automotive Simulation and Control Jilin UniversityJilin UniversityChangchun 130025China College of Communication Engineering Jilin UniversityJilin UniversityChangchun 130025China Department of Electromechanical Engineering University of MacaoMacao 999078China School of Artificial Intelligence Jilin UniversityChangchun 130012China IEEE College of Electronics and Information Engineering Tongji UniversityShanghai 200092China

Aiming at the tracking problem of a class of discrete nonaffine nonlinear multi-input multi-output(MIMO) repetitive systems subjected to separable and nonseparable disturbances, a novel data-driven iterative learning control(ILC) scheme based on the zeroing neural networks(ZNNs) is proposed. First, the equivalent dynamic linearization data model is obtained by means of dynamic linearization technology, which exists theoretically in the iteration domain. Then, the iterative extended state observer(IESO) is developed to estimate the disturbance and the coupling between systems, and the decoupled dynamic linearization model is obtained for the purpose of controller synthesis. To solve the zero-seeking tracking problem with inherent tolerance of noise,an ILC based on noise-tolerant modified ZNN is proposed. The strict assumptions imposed on the initialization conditions of each iteration in the existing ILC methods can be absolutely removed with our method. In addition, theoretical analysis indicates that the modified ZNN can converge to the exact solution of the zero-seeking tracking problem. Finally, a generalized example and an application-oriented example are presented to verify the effectiveness and superiority of the proposed process.

关键词： Adaptive control control system synthesis data-driven iterative learning control neurocontroller nonlinear discrete time systems

Engineering Strategies for Suppressing the Shuttle Effect in Lithium–Sulfur Batteries

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Nano-Micro Letters 2024年第1期16卷 187-221页

作者： Jiayi Li Li gao Fengying Pan Cheng Gong Limeng Sun hong gao Jinqiang zhang Yufei Zhao Guoxiu Wang Hao Liu Joint International Laboratory On Environmental and Energy Frontier Materials School of Environmental and Chemical EngineeringShanghai UniversityShanghaiPeople’s Republic of China Centre for Clean Energy Technology University of Technology SydneyBroadwaySydneyNSW 2007Australia

Lithium–sulfur(Li–S)batteries are supposed to be one of the most potential next-generation batteries owing to their high theoretical capacity and low ***,the shuttle effect of firm multi-step two-electron reaction between sulfur and lithium in liquid electrolyte makes the capacity much smaller than the theoretical *** methods were proposed for inhibiting the shuttle effect of polysulfide,improving corresponding redox kinetics and enhancing the integral performance of Li–S ***,we will comprehensively and systematically summarize the strategies for inhibiting the shuttle effect from all components of Li–S ***,the electrochemical principles/mechanism and origin of the shuttle effect are described in ***,the efficient strategies,including boosting the sulfur conversion rate of sulfur,confining sulfur or lithium polysulfides(LPS)within cathode host,confining LPS in the shield layer,and preventing LPS from contacting the anode,will be discussed to suppress the shuttle ***,recent advances in inhibition of shuttle effect in cathode,electrolyte,separator,and anode with the aforementioned strategies have been summarized to direct the further design of efficient materials for Li–S ***,we present prospects for inhibition of the LPS shuttle and potential development directions in Li–S batteries.

关键词： Shuttle effect Designed strategies Li-S battery Lithium polysulfides

Nuclear phylogenomics of Asteraceae with increased sampling provides new insights into convergent morphological and molecular evolution

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Plant Communications 2024年第6期5卷 117-138页

作者： Guojin zhang Junbo Yang Caifei zhang Bohan Jiao JoséL.Panero Jie Cai Zhi-Rong zhang Lian-Ming gao Tiangang gao hong Ma College of Life Sciences Hunan Normal UniversityChangshaHunan 410081China Department of Biology the Huck Institute of the Life Sciencesthe Pennsylvania State UniversityState CollegePA 16801USA State Key Laboratory of Plant Diversity and Specialty Crops Institute of BotanyChinese Academy of SciencesBeijing 100093China Germplasm Bank of Wild Species Kunming Institute of BotanyChinese Academy of SciencesKunmingYunnan 650201China Wuhan Botanical Garden and Sino-Africa Joint Research Center Chinese Academy of SciencesWuhan 430074China Department of Integrative Biology University of TexasAustinTX 78712USA CAS Key Laboratory for Plant Diversity and Biogeography of East Asia Kunming Institute of BotanyChinese Academy of SciencesKunmingYunnan 650201China Lijiang National Forest Biodiversity National Observation and Research Station Kunming Institute of BotanyChinese Academy of SciencesLijiangYunnan 674100China

Convergent morphological evolution is widespread in flowering plants,and understanding this phenomenon relies on well-resolved *** phylogenetic reconstruction using transcriptome datasets has been successful in various angiosperm groups,but it is limited to taxa with available fresh ***,which are one of the two largest angiosperm families and are important for both ecosystems and human livelihood,show multiple examples of convergent *** Asteraceae phylogenies have resolved relationships among most subfamilies and many tribes,but many phylogenetic and evolutionary questions regarding subtribes and genera remain,owing to limited ***,we increased the sampling for Asteraceae phylogenetic reconstruction using transcriptomes and genome-skimming datasets and produced nuclear phylogenetic trees with 706 species representing two-thirds of recognized *** character reconstruction supports multiple convergent evolutionary events in Asteraceae,with gains and losses of bilateral floral symmetry correlated with diversification of some subfamilies and smaller groups,*** of the calyx-related pappus may have been especially important for the success of some subtribes and *** evolutionary analyses support the likely contribution of duplications of MADS-box and TCP floral regulatory genes to innovations in floral morphology,including capitulum inflorescences and bilaterally symmetric flowers,potentially promoting the diversification of *** divergences and reductions in CYC2 gene expression are related to the gain and loss of zygomorphic *** phylogenomic work with greater taxon sampling through inclusion of genome-skimming datasets reveals the feasibility of expanded evolutionary analyses using DNA samples for understanding convergent evolution.

关键词： sunflower family floral symmetry florets capitulescence molecular clock ancestral character pappus subtribe MADS-box TCP CYC2 gene family gene expression

Investigating the Absorption and Desorption Behavior of Methylene Chloride in the Poly(aryl ether ketone) Film with Different Crystallinities

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Chinese Journal of Polymer Science 2024年第2期42卷 239-246,I0009页

作者： hong-Ru Yang Jin-Dong zhang Dong-Ting gao Gang Liu Chun-Hai Chen Jia-Nan Yao Center for Advanced Low-Dimension Materials State Key Laboratory for Modification of Chemical Fibers and Polymer MaterialsCollege of Materials Science and EngineeringDonghua UniversityShanghai201620China

Poly(aryl ether keton e)(PAEK) films with different crystallinities were obtained by controlling the cooling rate,which were subjected to the absorption and desorption of methylene chloride(CH_(2)Cl_(2)).We employed attenuated total reflection Fourier transform infrared(ATR-FTIR)spectroscopy analyses to investigate the diffusion behavior of CH_(2)Cl_(2) in PAEK films with different *** to the Fickian diffusion model,the calculated diffu sion coefficients of CH_(2)Cl_(2) in PAEK films were observed to decrease with increasing *** effect of CH_(2)Cl_(2)absorption and desorption on the mechanical properties of PAEK films with different crystallinity was further analyzed using tensile *** tensile tests exhibited that CH_(2)Cl_(2) has two concurrent effects:plasticization and solvent-induced *** scanning calorimetry(DSC) and wide-angle X-ray diffraction(WXRD) techniques further confirmed solvent-induced crystallization *** results would be beneficial to understand the solvent resistance of PAEK materials and consequently provide the practical application conditions of PAEK with a theoretical basis.

关键词： Poly(aryl ether ketone) Diffusion behavior Infrared spectra Solvent-induced crystallization Mechanical properties

Influencing factors of self-management ability among dry eye patients in west China

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International Journal of Ophthalmology(English edition) 2024年第9期17卷 1621-1627页

作者： Jie Ren Xin zhang Ji-hong Zeng Yun-Xia gao Department of Ophthalmology West China HospitalSichuan University/West China School of NursingSichuan UniversityChengdu 610041Sichuan ProvinceChina

AIM:To investigate the current situation and influencing factors of self-management ability in dry eye patients in west ***:A total of 265 patients clinically diagnosed with dry eye received a convenience survey questionnaire at West China Hospital of Sichuan *** participants completed the rating scale of health self-management skill for adults(AHSMSRS),Huaxi Emotional-Distress Index(HEI),e-health literacy scale(e-HEALS)and Brief Illness Perception Questionnaire(Brief-IPQ).A generalized linear model was employed to establish a multivariate linear model with demographic data,psychological state,e-HEALS,and illness perception as independent variables and health selfmanagement skill score as the dependent ***:The mean score for health self-management skill was 165.58±*** analysis revealed that advanced age,better illness perception and improved psychological state were associated with better health selfmanagement ability among dry eye ***,the health self-management ability of patients with a disease duration less than 1y was found to be higher compared to those with a disease duration exceeding ***:The health self-management ability of dry eye patients in west China is relatively ***,duration of disease,illness perception and psychological state are the influencing factors on the health selfmanagement ability of dry eye patients.

关键词： dry eye self-management ability influencing factors