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changes of Leaf Morphological, Anatomical Structure and carbon Isotope Ratio with the Height of the Wangtian Tree (Parashorea chinensis) in Xishuangbanna, china

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journal of Integrative Plant Biology 2008年第2期50卷 168-173页

作者： chun-Xia He ji-Yue Li Ping Zhou Ming Guo quan-Shui Zheng Key Laboratory for Silviculture and conservation Ministry of Education Beijing Forestry University Beijing 100083 China Viikki Tropical Resources Institute University of Helsinki FIN-00014 Helsinki Finland Department of Engineering Mechanics of Tsinghua University Beijing 100084 China

Leaf morphological and anatomical structure and carbon isotope ratio （δ^13c） change with increasing tree height. To determine how tree height affects leaf characteristics, we measured the leaf area, specific leaf mass （ratio of leaf mass to leaf area [LMA]）, thickness of the total leaf, cuticle, epidermis, palisade and sponge mesophyll, stomata traits and δ^13c at different heights of Parashorea chinensis with methods of light and scanning electron microscopy （SEM） and isotope-ratio mass spectrometry. The correlation and stepwise regression between tree height and leaf structure traits were carried out with SPSS software. The results showed that leaf structures and δ^13c differed significantly along the tree height gradient. The leaf area, thickness of sponge mesophyll and size of stomata decreased with increasing height, whereas the thickness of lamina, palisade mesophyll, epidermis, and cuticle, ratios of palisade to spongy thickness, density of stomata and vascular bundles, LMA and δ^13c increased with tree height. Tree height showed a significant relationship with all leaf indices and the most significant relationship was with epidermis thickness, leaf area, cuticle thickness, δ^13c. The δ^13c value showed a significantly positive relationship with LMA （R = 0.934）. Our results supported the hypothesis that the leaf structures exhibited more xeromorphic characteristics with the increasing gradient of tree height.

关键词： δ^13c anatomy morphology Parashorea chinensis ratio of leaf mass to leaf area.

changes in particulate and mineral-associated organic carbon with land use in contrasting soils

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Pedosphere 2023年第3期33卷 421-435页

作者： Sabina YEASMIN Balwant SINGH cliff T.jOHNSTON quan HUA Donald L.SPARKS Sydney Institute of Agriculture School of Life and Environmental SciencesThe University of SydneySydney NSW 2006(Australia) Department of Agronomy Bangladesh Agricultural UniversityMymensingh-2202(Bangladesh) crop Soil and Environmental SciencesPurdue UniversityWest Lafayette IN 47907(USA) Australian Nuclear Science and Technology Organisation Locked Bag 2001Kirrawee DC NSW 2232(Australia) Department of Plant and Soil Sciences University of DelawareNewark DE 19716(USA)

Soil organic carbon(SOc)is the largest terrestrial carbon(c)stock,and the capacity of soils to preserve organic c(Oc)varies with many factors,including land use,soil type,and soil *** investigated the effect of land use change on soil particulate organic matter(POM)and mineral-associated organic matter(MOM).Surface(0–10 cm)and subsurface(60–70 cm)samples were collected from paired sites(native and cropped)of four contrasting *** soils were separated into POM and MOM fractions,which were analyzed for mineralogy,Oc,nitrogen,isotopic signatures,*** POM fractions of surface soils were relatively unaffected by land use change,possibly because of the continuous input of crop residues,whereas the POM fractions in corresponding subsurface soils lost more *** surface soils,MOM fractions dominated by the oxides of iron and aluminum(oxide-OM)lost more Oc than those dominated by phyllosilicates and quartz,which was attributed to diverse organic matter(OM)input and the extent of Oc saturation limit of *** contrast,oxide-OM fractions were less affected than the other two MOM fractions in the subsurface soils,possibly due to Oc protection via organo-mineral *** deviations in isotopic signature(linked with vegetation)across the fractions suggested that fresh crop residues constituted the bulk of OM in surface soils(supported by greater14c).Increased isotopic signatures and lower14c in subsurface MOM fractions suggested the association of more microbially processed,aged Oc with oxide-OM fractions than with the other MOM *** results reveal that the quantity and quality of Oc after land use change is influenced by the nature of c input in surface soils and by mineral-organic association in subsurface soils.

关键词： land use change microbial decomposition organic carbon saturation organo-mineral association soil organic matter

Tricarboxy Ligand cuⅡ Metal-organic Framework with Magnetic and Proton conduction Properties

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chinese journal of Structural chemistry 2020年第9期39卷 1689-1693,1556页

作者： SHEN Zhi LUO Bao-Min XIE Hai-quan ZHAO Qiang college of chemistry and Pharmaceutical Engineering Nanyang Normal UniversityNanyang 473061China

Hydrothermal reaction of cu(NO3)2·3 H2O and 4-(4-carboxyphenoxy)isophthalic acid(H3cpia)results in a two-dimensional coordination polymer based on paddle-wheel-like dinuclear clusters,namely[c60H54cu4O39]n(1).complex 1 is of triclinic system,space group P1 with a=10.7318(18),b=12.267(2),c=14.528(2)?,α=113.560(2)o,β=96.156(3)o,γ=103.552(3)o,V=1660.5(5)?3,Z=1,S=1.057,F(000)=842,R=0.0517 and wR=0.1426(I>2σ(I)).In this structure,tricarboxylate liagnds are partial deprotonation and potenial proton *** antiferromagnetic interaction between cuⅡions exists within the cu2 cluster and complex 1 exhibits relatively high proton conductivity(σ>1.23×10-5 S×cm-1)at 76%relative humidity(RH).

关键词： metal-organic framework tricarboxylate ligands magnetic properties proton conductivity

2024 Adult compendium of Physical Activities:A third update of the energy costs of human activities

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journal of Sport and Health Science 2024年第1期13卷 6-12页

作者： Stephen D.Herrmann Erik A.Willis Barbara E.Ainsworth Tiago V.Barreira Mary Hastert chelsea L.Kracht john M.Schuna jr. Zhenghui cai Minghui quan catrine Tudor-Locke Melicia c.Whitt-Glover David R. jacobs jr. Kansas center for Metabolism and Obesity Research University of Kansas Medical CenterKansas CityKS 66160USA Division of Physical Activity and Weight Management Department of Internal MedicineUniversity of Kansas Medical CenterKansas CityKS 66160USA center for Health Promotion and Disease Prevention University of North Carolina at Chapel HillChapel HillNC 27599USA college of Health Solutions Arizona State UniversityPhoenixAZ 85003USA School of Exercise and Health Shanghai University of SportShanghai 200438China Exercise Science Department Syracuse UniversitySyracuseNY 13244USA clinical Sciences Division Pennington Biomedical Research CenterBaton RougeLA 70808USA School of Exercise and Sport Science Oregon State UniversityCorvallisOR 97331USA college of Health and Human Services University of North Carolina at CharlotteCharlotteNC 28223USA Gramercy Research Group KnightdaleNC 27545USA Division of Epidemiology and community Health School of Public HealthUniversity of MinnesotaMinneapolisMN 55454USA

Background:The compendium of Physical Activities was published in 1993 to improve the comparability of energy expenditure values assigned to self-reported physical activity(PA)across *** original version was updated in 2000,and again in 2011,and has been widely used to support PA research,practice,and public health ***:This 2024 update was tailored for adults 19-59 years of age by removing data from those≥60 *** a systematic review and supplementary searches,we identified new activities and their associated measured metabolic equivalent(MET)values(using indirect calorimetry)published since *** replaced estimated METs with measured values when ***:We screened 32,173 abstracts and 1507 full-text papers and extracted 2356 PA energy expenditure values from 701 *** added303 new PAs and adjusted 176 existing MET values and descriptions to reflect the addition of new data and removal of METs for older *** added a Major Heading(Video Games).The 2024 Adult compendium includes 1114 PAs(912 with measured and 202 with estimated values)across 22 Major ***:This comprehensive update and refinement led to the creation of The 2024 Adult compendium,which has utility across research,public health,education,and healthcare domains,as well as in the development of consumer health *** new website with the complete lists of PAs and supporting resources is available at https://***.

关键词： Adults Energy expenditure Exercise MET Physical Activities

cT灌注对急性缺血性卒中患者侧支状态评估的价值研究

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中国cT和MRI杂志 2025年第1期23卷 10-12页

作者：李权麟胡雪姣庞占琪联勤保障部队第九六七医院放射诊断科辽宁大连116000 联勤保障部队大连康复疗养中心疗养二科辽宁大连116000 大连市中心医院神经内科辽宁大连116010

目的建立cT侧支循环血流灌注的定量评估方法,并探讨其在预测急性缺血性卒中(AIS)患者预后中的价值。方法回顾性分析本院于2020年1月至2023年11月期间连续接受大脑中动脉M1段闭塞的204名AIS患者数据,他们接受了预处理灌注cT检查。计算... 详细信息

目的建立cT侧支循环血流灌注的定量评估方法,并探讨其在预测急性缺血性卒中(AIS)患者预后中的价值。方法回顾性分析本院于2020年1月至2023年11月期间连续接受大脑中动脉M1段闭塞的204名AIS患者数据,他们接受了预处理灌注cT检查。计算侧裂内侧支血管的最大脑血流量(ccBFmax)。预后良好定义为90天改良Rankin评分0~2分。采用多变量Logisti c回归分析ccB Fmax与(A)出血转化和(B)临床预后的关系。结果多变量Logisti c回归分析显示,较高的ccBFmax是一个独立的预测因素:(A)在调整了卒中评分(NIHSS)、血管内血栓切除术、基线梗死核心体积和再通后,出血转化的风险较低(优势比[OR],0.99;95%可信区间[cI]:0.98,1.00;P=0.009);(B)在调整了年龄、基线NIHSS评分、血管内血栓切除术、高血压、基线心肌梗死核心体积和再通后,预后较好(OR,1.02;95%cI:1.01,1.03;P=0.001)。结论测量侧裂内侧支血管的最大脑血流量是一种可行的定量侧支cT评估方法,侧支血管的最大脑血流量与急性缺血性卒中患者的临床转归相关。

关键词： cT灌注缺血性卒中侧支状态

Effect of volume fraction and mechanical stability of austenite on ductility of medium Mn steel

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journal of Iron and Steel Research International 2019年第11期26卷 1209-1218页

作者： Si-lian che Zhao-xi cao chang Wang chong-xiang Huang Dirk Ponge Wen-quan cao central Iron and Steel Research Institute(cISRI) Beijing 100081China Science Faculty University of SydneySydney NSW 2006Australia School of Aeronautics and Astronautics Sichuan UniversityChengdu 610065SichuanChina Max-Planck-Institute for Iron Research Duesseldorf 40237Germany

A hot-rolled medium Mn(0.2c5Mn)steel is annealed at 650℃ to produce an ultrafine-grained duplex microstructure with different austenite volume fractions by austenite reverted transformation(ART)annealing,and the orientation relationship strictly obeys K-S orientation relationship before *** tests are carried out in a temperature range from-196 to 400℃ to examine the effects of the austenite volume fraction and the deformation temperature on the tensile properties and the austenite *** observations reveal that the metastable austenite gradually transformed into a-martensite,which is controlled by the deformation strain,the temperature and the austenite volume *** strain hardening behavior and ductility of the studied steel are dependent on austenite volume fraction and deformation temperature *** stress-strain curves of ART-annealed 0.2c5Mn steel assume an S shape and a very large work hardening rate of about 10 GPa is obtained at liquid nitrogen deformation *** on the experimental data,a quantitative relation is proposed to describe the ductility dependence on both the austenite volume fraction and its mechanical stability.

关键词： TRIP effect Ductility Phase transformation Austenite volume fraction Mechanical stability

TSc prediction and dynamic control of BOF steelmaking with state-of-the-art machine learning and deep learning methods

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journal of Iron and Steel Research International 2024年第1期31卷 174-194页

作者： Tian-yi Xie cai-dong Zhang quan-lin Zhou Zhi-qiang Tian Shuai Liu Han-jie Guo Material Technology Research Institute Hesteel GroupShijiazhuang050023HebeiChina Tangsteel company Hesteel GroupTangshan063611HebeiChina School of Artificial Intelligence Beijing Technology and Business UniversityBeijing100048China School of Metallurgical and Ecological Engineering University of Science and Technology BeijingBeijing100083China

Mathematical(data-driven)models based on state-of-the-art(SOTA)machine learning and deep learning models and data collected from 12,786 heats were established to predict the values of temperature,sample,and carbon(TSc)test,including temperature of molten steel(TSc-Temp),carbon content(TSc-c)and phosphorus content(TSc-P),which made prepa-ration for eliminating the TSc *** maximize the prediction accuracy of the proposed approach,various models with different inputs were implemented and compared,and the best models were applied to the production process of a Hesteel Group steelmaking plant in china in the *** number of tabular features(hot metal information,scrap,additives,blowing practices,and preset values)was expanded,and time series(off-gas profiles and blowing practice curves)that could reflect the entire steelmaking process were introduced as ***,the latest machine learning models(LightGBM,catBoost,TabNet,and NODE)were used to make predictions with tabular features,and the best coefficient of determination R^(2)values obtained for TSc-P,TSc-c and TSc-Temp predictions were 0.435(LightGBM),0.857(cat-Boost)and 0.678(LightGBM),respectively,which were higher than those of classic models(backpropagation and support vector machine).Then,making predictions was performed by using SOTA time series regression models(ScINet,DLinear,Informer,and MLSTM-FcN)with original time series,SOTA image regression models(NesT,caiT,ResNeXt,and GoogLeNet)with resized time series,and the proposed concatenate-Model and Parallel-Model with both tabular features and time *** optimization and comparisons,it was finally determined that the concatenate-Model with MLSTM-FcN,ScINet and Informer as feature extractors performed the best,and its R^(2)values for predicting TSc-P,TSc-c and TSc-Temp reached 0.470,0.858 and 0.710,*** field test accuracies for TSc-P,TSc-c and TSc-Temp were 0.459,0.850 and 0.685,respectively.A related importance analysis was carri

关键词： BOF steelmaking In-blow prediction TSc test Machine learning Deep learning Field application

High Ductility and Toughness of a Micro-duplex Medium-Mn Steel in a Large Temperature Range from—196 ℃ to 200 ℃

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journal of Iron and Steel Research International 2015年第12期22卷 1126-1130页

作者： Si-lian cHEN jun HU Xiao-dan ZHANG Han DONG Wen-quan cAO central Iron and Steel Research Institute School of Materials Science and Engineering Huazhong University of Science and Technology Danish-chinese centre for Nanometals Section for Materials Science and Advanced CharacterizationDepartment of Wind EnergyTechnical University of Denmark

A medium-Mn steel （0.2c5Mn） was processed by intercritical annealing at different temperatures （625 ℃ and 650 ℃ ）. An ultrafine-grained micro-duplex structure consisting of alternating austenite and ferrite laths was de- veloped by austenite reverse transformation （ART） during intercritical annealing after forging and hot rolling. Ultra- high ductility with a total elongation higher than 30% was achieved in the temperature range from -196 ℃ to 200 ℃, and high impact toughness no less than 200 j at -40 ℃ was obtained. Based on the analysis of microstructure and mechanical properties, it was found that the enhanced ductility was determined by the phase transformation effect of austenite （TRIP effect）, while the delayed ductile to brittle transition was controlled by austenite stability.

关键词： high strength high ductility intercritical annealing medium-Mn steel ultrafine grain size

calculation and Analysis of Force in Roll System of 20-High Sendzimir Mill

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journal of Iron and Steel Research International 2013年第9期20卷 33-39页

作者： WANG Zhao-hui GAO quan-jie YAN chao XIA Zhi-yong ZHANG Yao-bing Key Laboratory of Metallurgical Equipment and control of Education Ministry Wuhan University of Science and Technology

The calculation of force for a roll system has significant effects on cold roiled thin strip gauge adjustment of a 20-high Sendzimir mill. According to the rolling parameters and rolling plans of a ZR 22B-42 Sendzimir mill in a silicon steel factory, the contact force and the resultant force of each roll in the roll system were calculated both in the static state and in the rolling state through c＋＋ programs. It was found that the contact force between the see ond intermediate driven roll and the back up rolls B and c was much lower than that between the other rolls in static state. The results also demonstrated that the resultant force are 59.5%-62%, 37.7%-40.3%, 87.1%-88.7% and 53.9%-56.7% of the rolling force at the second intermediate driven roll, the second intermediate idler roll, the back-up rolls B and c and the back-up rolls A and D, respectively. It was also revealed that the minimum contact force generated between the first intermediate roll and the second intermediate idler roll is 206.7 kN on the first roll ing pass, and that on the second rolling pass, the minimum contact force generated between the second intermediate driven roll and the back-up roll c is 470.7 kN.

关键词： Sendzimir mill roll system static state rolling force