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Activation of adult endogenous neurogenesis by a hyaluronic acid collagen gel containing basic fibroblast growth factor promotes remodeling and functional recovery of the injured cerebral cortex
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作者 Yan Li Peng Hao +6 位作者 Hongmei Duan Fei Hao Wen Zhao Yudan Gao Zhaoyang Yang Kwok-Fai So Xiaoguang Li 《Neural Regeneration Research》 SCIE CAS 2025年第10期2923-2937,共15页
The presence of endogenous neural stem/progenitor cells in the adult mammalian brain suggests that the central nervous system can be repaired and regenerated after injury.However,whether it is possible to stimulate ne... The presence of endogenous neural stem/progenitor cells in the adult mammalian brain suggests that the central nervous system can be repaired and regenerated after injury.However,whether it is possible to stimulate neurogenesis and reconstruct cortical layers II to VI in non-neurogenic regions,such as the cortex,remains unknown.In this study,we implanted a hyaluronic acid collagen gel loaded with basic fibroblast growth factor into the motor cortex immediately following traumatic injury.Our findings reveal that this gel effectively stimulated the proliferation and migration of endogenous neural stem/progenitor cells,as well as their differentiation into mature and functionally integrated neurons.Importantly,these new neurons reconstructed the architecture of cortical layers II to VI,integrated into the existing neural circuitry,and ultimately led to improved brain function.These findings offer novel insight into potential clinical treatments for traumatic cerebral cortex injuries. 展开更多
关键词 adult endogenous neurogenesis basic fibroblast growth factor-hyaluronic acid collagen gel cortical remodeling functional recovery migration motor cortex injury neural circuits neural stem cells newborn neurons proliferation
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Activation of endogenous neurogenesis and angiogenesis by basic fibroblast growth factor-chitosan gel in an adult rat model of ischemic stroke 被引量:6
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作者 Hongmei Duan Shulun Li +11 位作者 Peng Hao Fei Hao Wen Zhao Yudan Gao Hui Qiao Yiming Gu Yang Lv Xinjie Bao Kin Chiu Kwok-Fai So Zhaoyang Yang Xiaoguang Li 《Neural Regeneration Research》 SCIE CAS CSCD 2024年第2期409-415,共7页
Attempts have been made to use cell transplantation and biomaterials to promote cell proliferation,differentiation,migration,and survival,as well as angiogenesis,in the context of brain injury.However,whether bioactiv... Attempts have been made to use cell transplantation and biomaterials to promote cell proliferation,differentiation,migration,and survival,as well as angiogenesis,in the context of brain injury.However,whether bioactive materials can repair the damage caused by ischemic stroke by activating endogenous neurogenesis and angiogenesis is still unknown.In this study,we applied chitosan gel loaded with basic fibroblast growth factor to the stroke cavity 7 days after ischemic stroke in rats.The gel slowly released basic fibroblast growth factor,which improved the local microenvironment,activated endogenous neural stem/progenitor cells,and recruited these cells to migrate toward the penumbra and stroke cavity and subsequently differentiate into neurons,while enhancing angiogenesis in the penumbra and stroke cavity and ultimately leading to partial functional recovery.This study revealed the mechanism by which bioactive materials repair ischemic strokes,thus providing a new strategy for the clinical application of bioactive materials in the treatment of ischemic stroke. 展开更多
关键词 adult endogenous neurogenesis ANGIOGENESIS basic fibroblast growth factor-chitosan gel CHITOSAN functional recovery ischemic stroke neural stem cell newborn neuron
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Delineation of urban growth boundary based on FLUS model under the perspective of land use evaluation in hilly mountainous areas 被引量:1
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作者 ZHANG Yunping LIN Jianping +3 位作者 HUANG Yimin CHEN Zebin ZHU Chenhui YUAN Hao 《Journal of Mountain Science》 SCIE CSCD 2024年第5期1647-1662,共16页
With rapid economic development,the size of urban land in China is expanding dramatically.The Urban Growth Boundary(UGB)is an expandable spatial boundary for urban construction in a certain period in order to control ... With rapid economic development,the size of urban land in China is expanding dramatically.The Urban Growth Boundary(UGB)is an expandable spatial boundary for urban construction in a certain period in order to control the urban sprawl.Reasonable delineation of UGB can inhibit the disorderly spread of urban space and guide the normal development of the city.It is of practical significance for the construction of green urban space.The study utilizes GIS technology to establish a land construction suitability evaluation system for Nankang city,which is experiencing rapid urban expansion,and outlines the preliminary UGB under the future land use simulation(FLUS)model.At the same time,considering the coupled coordination of"Production-Living-Ecological Space",and based on the suitability evaluation,we revised the preliminary UGB by combining the advantages of the patch-generating land use simulation(PLUS)model and the convex hull model to delineate the final UGB.The results show that:1)the comprehensive score of the evaluation of the suitability of the construction of land from high to low shows the distribution of the center of the city to the surrounding circle type spread,the center of the city has the highest suitability score.The results of convex hull model show that the urban expansion type of Nankang is epitaxial.In the future,the urban expansion will mainly occur in the northern part of the city.The PLUS model predicts an increase of 3359.97 hm^(2)of construction land in Nankang by 2035,of which 2022.97 hm^(2)is urban construction land.2)The FLUS model has a prediction accuracy of 86.3%and delineates a preliminary UGB area of 9215.07 hm^(2).3)We used the results of the construction suitability evaluation,PLUS model simulation results,and convex hull model predictions to revise the originally delineated UGB.The final delineated UGB area is 8895.67 hm^(2)and it is capable of meeting the future development of the study area.The results of the delineation can promote sustainable urban development,and the delineation methodology can provide a reference basis for the preparation of territorial spatial planning. 展开更多
关键词 Urban sprawl FLUS model Spatial correction Urban growth boundary Sustainable development
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Effects of leukemia inhibitory factor and basic fibroblast growth factor on free radicals and endogenous stem cell proliferation in a mouse model of cerebral infarction 被引量:2
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作者 Weihui Huang Yadan Li +2 位作者 Yufeng Lin Xue Ye Dawei Zang 《Neural Regeneration Research》 SCIE CAS CSCD 2012年第19期1469-1474,共6页
The present study established a mouse model of cerebral infarction by middle cerebral artery occlusion, and monitored the effect of 25 tJg/kg leukemia inhibitory factor and (or) basic fibroblast growth factor admini... The present study established a mouse model of cerebral infarction by middle cerebral artery occlusion, and monitored the effect of 25 tJg/kg leukemia inhibitory factor and (or) basic fibroblast growth factor administration 2 hours after model establishment. Results showed that following administration, the number of endogenous neural stem cells in the infarct area significantly increased, malondialdehyde content in brain tissue homogenates significantly decreased, nitric oxide content, glutathione peroxidase and superoxide dismutase activity significantly elevated, and mouse motor function significantly improved as confirmed by the rotarod and bar grab tests. In particular, the effect of leukemia inhibitory factor in combination with basic fibroblast growth factor was the most significant. Results indicate that leukemia inhibitory factor and basic fibroblast growth factor can improve the microenvironment after cerebral infarction by altering free radical levels, improving the quantity of endogenous neural stem cells, and promoting neurological function of mice with cerebral infarction. 展开更多
关键词 leukemia inhibitory factor basic fibroblast growth factor endogenous neural stem cells free radical MALONDIALDEHYDE nitric oxide glutathione peroxidase superoxide dismutase NEUROPROTECTION
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Growth and inhibition of zinc anode dendrites in Zn-air batteries:Model and experiment
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作者 Cuiping He Qingyi Gou +6 位作者 Yanqing Hou Jianguo Wang Xiang You Ni Yang Lin Tian Gang Xie Yuanliang Chen 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2024年第3期268-281,共14页
Zinc(Zn)-air batteries are widely used in secondary battery research owing to their high theoretical energy density,good electrochemical reversibility,stable discharge performance,and low cost of the anode active mate... Zinc(Zn)-air batteries are widely used in secondary battery research owing to their high theoretical energy density,good electrochemical reversibility,stable discharge performance,and low cost of the anode active material Zn.However,the Zn anode also leads to many challenges,including dendrite growth,deformation,and hydrogen precipitation self-corrosion.In this context,Zn dendrite growth has a greater impact on the cycle lives.In this dissertation,a dendrite growth model for a Zn-air battery was established based on electrochemical phase field theory,and the effects of the charging time,anisotropy strength,and electrolyte temperature on the morphology and growth height of Zn dendrites were studied.A series of experiments was designed with different gradient influencing factors in subsequent experiments to verify the theoretical simulations,including elevated electrolyte temperatures,flowing electrolytes,and pulsed charging.The simulation results show that the growth of Zn dendrites is controlled mainly by diffusion and mass transfer processes,whereas the electrolyte temperature,flow rate,and interfacial energy anisotropy intensity are the main factors.The experimental results show that an optimal electrolyte temperature of 343.15 K,an optimal electrolyte flow rate of 40 ml·min^(-1),and an effective pulse charging mode. 展开更多
关键词 Zn-air battery Zinc anode Zinc dendrite Simulated dendrite growth Inhibit dendrite growth Phase-field model
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Interpreting Larix principis-rupprechtii radial growth in northern China based on the Vaganov-Shashkin model
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作者 Jiachuan Wang Shuheng Li +4 位作者 Qiang Li Yili Guo Yijie Han Qi Liu Yiqi Zhao 《Journal of Forestry Research》 SCIE EI CAS CSCD 2024年第3期99-110,共12页
Changes in annual radial growth is an important indication of climate change. Dendroclimatology studies in northern China have focused on linear statistical analysis,but lacking studies based on the process of ring fo... Changes in annual radial growth is an important indication of climate change. Dendroclimatology studies in northern China have focused on linear statistical analysis,but lacking studies based on the process of ring formation to clarify the radial growth of trees. Tree-ring width standard chronology(STD) was established using samples of Larix principis-rupprechtii collected at 2303 m altitude on Luya Mountain. Using the Vaganov-Shashkin(VS) model to simulate growth and development, the internal physiological mechanism of radial growth is identified. It was concluded that:(1) the growing season of L. principis-rupprechtii was May to September;(2) soil moisture was a significant factor in the early and late growing seasons, and temperature was the dominant factor in its main growth period;and(3) formation of narrow ring widths was closely related to drought stress, the development of wide ring widths will be restricted by increasing future temperatures. The VS model is applicable for radial growth simulation of subalpine coniferous forests and for guiding the cultivation of local tree species in the future. 展开更多
关键词 Vaganov-Shashkin model Larix principis-rupprechti Tree-ring width Annual growth
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Microbial Growth and Decay: A Commented Review of the Model
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作者 Alberto Schiraldi 《Advances in Microbiology》 CAS 2024年第1期1-10,共10页
The paper reviews previous publications and reports some comments about a semi empirical model of the growth and decay process of a planktonic microbial culture. After summarizing and reshaping some fundamental mathem... The paper reviews previous publications and reports some comments about a semi empirical model of the growth and decay process of a planktonic microbial culture. After summarizing and reshaping some fundamental mathematical expressions, the paper highlights the reasons for the choice of a suitable time origin that makes the parameters of the model self-consistent. Besides the potential applications to predictive microbiology studies and to effects of bactericidal drugs, the model allows a suitable proxy of the fitness of the microbial culture, which can be of interest for the studies on the evolution across some thousand generations of a Long Term Evolution Experiment. 展开更多
关键词 Microbial Cultures model Time Scale growth and Decay EVOLUTION
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Ecosystem service multifunctionality of mixed conifer-broad-leaved forests under climate change and forest management based on matrix growth modelling
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作者 Xue Du Xiangdong Lei +3 位作者 Xiao He Jie Lan Hong Guo Qigang Xu 《Forest Ecosystems》 SCIE CSCD 2024年第5期743-757,共15页
Climate change and forest management are recognized as pivotal factors influencing forest ecosystem services and thus multifunctionality.However,the magnitude and the relative importance of climate change and forest m... Climate change and forest management are recognized as pivotal factors influencing forest ecosystem services and thus multifunctionality.However,the magnitude and the relative importance of climate change and forest management effects on the multifunctionality remain unclear,especially for natural mixed forests.In this study,our objective is to address this gap by utilizing simulations of climate-sensitive transition matrix growth models based on national forest inventory plot data.We evaluated the effects of seven management scenarios(combinations of various cutting methods and intensities)on the future provision of ecosystem services and multifunctionality in mixed conifer-broad-leaved forests in northeastern China,under four climate scenarios(SSP1-2.6,SSP2-4.5,SSP5-8.5,and constant climate).Provisioning,regulating,cultural,and supporting services were described by timber production,carbon storage,carbon sequestration,tree species diversity,deadwood volume,and the number of large living trees.Our findings indicated that timber production was significantly influenced by management scenarios,while tree species diversity,deadwood volume,and large living trees were impacted by both climate and management separately.Carbon storage and sequestration were notably influenced by both management and the interaction of climate and management.These findings emphasized the profound impact of forest management on ecosystem services,outweighing that of climate scenarios alone.We found no single management scenario maximized all six ecosystem service indicators.The upper story thinning by 5%intensity with 5-year interval(UST5)management strategy emerged with the highest multifunctionality,surpassing the lowest values by more than 20%across all climate scenarios.In conclusion,our results underlined the potential of climate-sensitive transition matrix growth models as a decision support tool and provided recommendations for long-term strategies for multifunctional forest management under future climate change context.Ecosystem services and multifunctionality of forests could be enhanced by implementing appropriate management measures amidst a changing climate. 展开更多
关键词 Multifunctional forest management THINNING Transition matrix growth model Carbon sink Timber production
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The Impact of the Digital Economy on Financial Regulatory Costs: An Empirical Analysis Based on the Solow Growth Model
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作者 Dong Kang 《Contemporary Social Sciences》 2024年第5期70-94,共25页
As a novel economic form,the digital economy is reshaping the financial regulatory landscape and significantly impacting regulatory costs.This paper incorporates the digital economy and financial regulatory costs into... As a novel economic form,the digital economy is reshaping the financial regulatory landscape and significantly impacting regulatory costs.This paper incorporates the digital economy and financial regulatory costs into the classic Solow growth model,uncovering an inverted U-shaped relationship between them.A subsequent mechanism analysis explains the rationale behind this relationship.To empirically examine this relationship in China,the paper utilizes inter-provincial panel data from 2013 to 2021 and employs methodologies such as the two-way fixed effects and moderating effects models.These analyses have important implications for the sound and sustainable development of China’s financial industry.The findings indicate:(a)As China’s digital economy develops,its impact on financial regulatory costs follows an inverted U-shaped pattern,initially increasing and then declining.This conclusion remains valid after robustness tests.(b)The influence of the digital economy on regulatory costs depends on favorable external conditions.Specifically,the impact is more pronounced in regions and periods with better digital infrastructure and more abundant human capital.(c)Additionally,redundant resources moderate this impact,which can weaken the inverted U-shaped relationship.Our findings not only provide a theoretical foundation for understanding the impact of the digital economy on financial regulatory costs but also offer valuable policy insights for optimizing financial regulation in China. 展开更多
关键词 digital economy financial regulatory costs Solow growth model
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THE OPTIMAL ALLOCATION ABOUT CAPITAL AND LABOR IN THE ECONOMIC GROWTH WITH AN ENDOGENOUS TECHNICAL PROGRESS MODEL
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作者 刘金山 李楚霖 胡适耕 《Acta Mathematica Scientia》 SCIE CSCD 2002年第4期511-516,共6页
In this paper, the balanced economic growth path was considered in a new growth model with endogenous technical progress. It is not only obtained the optimal allocation about capital and labor between a goods-producin... In this paper, the balanced economic growth path was considered in a new growth model with endogenous technical progress. It is not only obtained the optimal allocation about capital and labor between a goods-producing sector and a R&D Sector, but also the optimal value of saving rates. By discussing the effect of parameters, it are also got the following results: When the rate of time preference (discount factor) rising, the fractions of Capital and labor in the goods-producing sector will increase, the fractions in R&D sector and the saving rates will decrease; When the population grows rapidly, the result will be contrary. 展开更多
关键词 utility function balanced growth path endogenous technical progress
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SAR Data Assimilation for Crop Biomass Simulation Based on Crop Growth Model 被引量:3
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作者 谭正 刘湘南 +1 位作者 张晓倩 吴伶 《Agricultural Science & Technology》 CAS 2012年第5期1127-1132,共6页
Biomass from SAR data was assimilated into crop growth model to describe relationship between crop biomass and crop growth time to improve estimation accuracy of biomass. In addition, inverse model was established in ... Biomass from SAR data was assimilated into crop growth model to describe relationship between crop biomass and crop growth time to improve estimation accuracy of biomass. In addition, inverse model was established in order to estimate biomass according to relationship between biomass and backscattering coefficients from SAR data. Based on cost function, parameters of growth model were optimized as per conjugate gradient method, minimizing the differences between estimated biomass and inversion values from SAR data. The results indicated that the simulated biomass using the revised growth model with SAR data was consistent with the measured one in time distribution and even higher in accuracy than that without SAR data. Hence, the key parameters of crop growth model could be revised by real-time growth information from SAR data and accuracy of the simulated biomass could be improved accordingly. 展开更多
关键词 Data assimilation BIOMASS SAR Crop growth model
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Phase-field modeling of dendritic growth under forced flow based on adaptive finite element method 被引量:2
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作者 朱昶胜 雷鹏 +1 位作者 肖荣振 冯力 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2015年第1期241-248,共8页
A mathematical model combined projection algorithm with phase-field method was applied. The adaptive finite element method was adopted to solve the model based on the non-uniform grid, and the behavior of dendritic gr... A mathematical model combined projection algorithm with phase-field method was applied. The adaptive finite element method was adopted to solve the model based on the non-uniform grid, and the behavior of dendritic growth was simulated from undercooled nickel melt under the forced flow. The simulation results show that the asymmetry behavior of the dendritic growth is caused by the forced flow. When the flow velocity is less than the critical value, the asymmetry of dendrite is little influenced by the forced flow. Once the flow velocity reaches or exceeds the critical value, the controlling factor of dendrite growth gradually changes from thermal diffusion to convection. With the increase of the flow velocity, the deflection angle towards upstream direction of the primary dendrite stem becomes larger. The effect of the dendrite growth on the flow field of the melt is apparent. With the increase of the dendrite size, the vortex is present in the downstream regions, and the vortex region is gradually enlarged. Dendrite tips appear to remelt. In addition, the adaptive finite element method can reduce CPU running time by one order of magnitude compared with uniform grid method, and the speed-up ratio is proportional to the size of computational domain. 展开更多
关键词 dendritic growth phase-field model forced flow adaptive finite element method
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A Simplified Model with Soil Water Limitation on Spring Wheat Growth 被引量:2
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作者 郑海雷 米谷俊颜 黄子琛 《Acta Botanica Sinica》 CSCD 2000年第5期512-517,共6页
The authors constructed a simplified model of spring wheat (Triticum aestivum L.) carbon assimilation and dry matter accumulation (DMA) process which consisted of two independent variables, day length (L) and total... The authors constructed a simplified model of spring wheat (Triticum aestivum L.) carbon assimilation and dry matter accumulation (DMA) process which consisted of two independent variables, day length (L) and total daily radiation (TDR). Leaf water potential (Ψ) was incorporated into the simplified growth model based on the assumption that both light use efficiency (α) and CO 2 conductance of assimilation (g c) were depressed by water limitation. Finally,Ψ was estimated from a regression equation in which the independent variables were relative soil water content in the upper 80 cm (θ R,80 ), ambient temperature (T a), vapor pressure deficit (VPD), the cumulative leaf water potential below thresholds of -1.5 MPa (Ψ c,1.5 ). Some applications in research program of field experiment of atmosphere_land surface processes in Heihe River region were tested. The simulated data agreed well with the data observed at Linze oasis in 1989 for various levels of water supply and at Zhangye oasis in 1992 in the field. The analysis and simulation using the model demonstrated that the simplified growth model could describe very well the DMA process of spring wheat with and without water limitation in the region of HEIFE (Heihe field experiment). 展开更多
关键词 spring wheat growth simplified model water limitation
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Study on height growth model of Pinus koraiensis 被引量:1
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作者 邓红兵 郝占庆 王庆礼 《Journal of Forestry Research》 SCIE CAS CSCD 2001年第3期192-194,210,共3页
Growth model is an efficient way to study growing process of some factors of plants quantitatively. Height growth of Korean pine (Pinus koraiensis) was studied by using Hyperbola equation, Logistic equation, Richards ... Growth model is an efficient way to study growing process of some factors of plants quantitatively. Height growth of Korean pine (Pinus koraiensis) was studied by using Hyperbola equation, Logistic equation, Richards equation with three parameters, and Richards equation with four parameters in this paper. The results showed that Richards equation with four parameters was the most suitable and could be turned into other theoretical equations when some parameters were given different value. The maximum height of trees could be given in advance when using Richards equation with four parameters, and it was even more corresponding to reality. In addition, a height growth model with real height of fixed age as a parameter was discussed in this paper. This kind of growth model could be used to calculate height growth of a given tree effectively. 展开更多
关键词 Korean pine Height growth model
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Studies on stand dynamic growth model for larch in Jilin in China 被引量:1
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作者 翁国庆 陈雪峰 《Journal of Forestry Research》 SCIE CAS CSCD 2004年第4期323-326,共4页
The stand growth and yield dynamic models for Larch in Jilin Province were developed based on the forest growth theories with the forest continuous inventory data. The results indicated that the developed models had h... The stand growth and yield dynamic models for Larch in Jilin Province were developed based on the forest growth theories with the forest continuous inventory data. The results indicated that the developed models had high precision, and they could be used for the updating data of inventory of planning and designing and optimal decision of forest management. 展开更多
关键词 Stand Dynamics growth Prediction model
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PROBABILISTIC MODELS FOR LONG FATIGUE CRACK GROWTH RATES OF LZ50 AXLE STEEL 被引量:5
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作者 赵永翔 何朝明 +3 位作者 杨冰 黄郁仲 高庆 邬平波 《应用数学和力学》 CSCD 北大核心 2005年第8期997-1002,共6页
Experimental study is performed on the probabilistic models for the long fatigue crack growth rates (da/dN) of LZ50 axle steel. An equation for crack growth rate was derived to consider the trend of stress intensity f... Experimental study is performed on the probabilistic models for the long fatigue crack growth rates (da/dN) of LZ50 axle steel. An equation for crack growth rate was derived to consider the trend of stress intensity factor range going down to the threshold and the average stress effect. The probabilistic models were presented on the equation. They consist of the probabilistic da/dN-ΔK relations, the confidence-based da/dN-ΔK relations, and the probabilistic- and confidence-based da/dN-ΔK relations. Efforts were made respectively to characterize the effects of probabilistic assessments due to the scattering regularity of test data, the number of sampling, and both of them. These relations can provide wide selections for practice. Analysis on the test data of LZ50 steel indicates that the present models are available and feasible. 展开更多
关键词 LZ50钢 疲劳长裂纹 扩展率 平均应力 门槛值 概率模型
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对《Plant Growth Modeling and Applications》一书的评介
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作者 熊范伦 《自动化学报》 EI CSCD 北大核心 2004年第3期F002-F002,共1页
农业信息技术能够快速完成农业科技、市场和政府等信息的传输和利用,加速科研成果的形成、规范、集成,缩短转化周期,科学指导和管理生产,从而改变传统农业高度分散、生产规模小、时空变异大、规模化程度差、稳定性和可控程度低等行业性... 农业信息技术能够快速完成农业科技、市场和政府等信息的传输和利用,加速科研成果的形成、规范、集成,缩短转化周期,科学指导和管理生产,从而改变传统农业高度分散、生产规模小、时空变异大、规模化程度差、稳定性和可控程度低等行业性弱点,提高农业生产者和管理者的素质和能力.农业信息化近些年来在我国有了快速的发展.2003年12月10日,我国科技部863计划支持的重大专项"智能化农业信息技术应用示范工程"(俗称"电脑农业")荣获世界信息峰会全球大奖,标志着中国在农业专家系统和智能化农业信息技术应用方面取得了重大成就. 展开更多
关键词 《Plant growth modeling and Applications》 农业信息技术 书评 “电脑农业” 中国 智能化农业信息技术
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Free dendritic growth model incorporating interfacial nonisosolutal nature due to normal velocity variation 被引量:1
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作者 李述 谷志慧 +3 位作者 李大勇 吴双双 陈明华 冯宇 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2015年第10期3363-3369,共7页
Considering both the effects of the interfacial normal velocity dependence of solute segregation and the local nonequilibrium solute diffusion,an extended free dendritic growth model was analyzed.Compared with the pre... Considering both the effects of the interfacial normal velocity dependence of solute segregation and the local nonequilibrium solute diffusion,an extended free dendritic growth model was analyzed.Compared with the predictions from the dendritic model with isosolutal interface assumption,the transition from solutal dendrite to thermal dendrite moves to higher undercoolings,i.e.,the region of undercoolings with solute controlled growth is extended.At high undercoolings,the transition from the mainly thermal-controlled growth to the purely thermal-controlled growth is not sharp as predicted by the isosolute model,but occurs in a range of undercooling,due to both the effects of the interfacial normal velocity dependence of solute segregation and the local nonequilibrium solute diffusion.Model test indicates that the present model can give a satisfactory agreement with the available experimental data for the Ni-0.7% B(mole fraction) alloy. 展开更多
关键词 dendritic growth interfacial nonisosolutal nature modelING binary alloy
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Optimizing Parameters of CSM-CERES-Maize Model to Improve Simulation Performance of Maize Growth and Nitrogen Uptake in Northeast China 被引量:15
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作者 LIU Hai-long YANG Jing-yi +9 位作者 HE Ping BAI You-lu JIN Ji-yun Craig F Drury ZHU Ye-ping YANGXue-ming LI Wen-juan XIE Jia-gui YANG Jing-min Gerrit Hoogenboom 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2012年第11期1898-1913,共16页
Crop models can be useful tools ibr optimizing fertilizer management for a targeted crop yield while minimizing nutrient losses. In this paper, the parameters of the decision support system for agrotechnology transfer... Crop models can be useful tools ibr optimizing fertilizer management for a targeted crop yield while minimizing nutrient losses. In this paper, the parameters of the decision support system for agrotechnology transfer (DSSAT)-CERES-Maize were optimized using a new method to provide a better simulation of maize (Zea mays L.) growth and N upfake in response to different nitrogen application rates. Field data were collected from a 5 yr field experiment (2006-2010) on a Black soil (Typic hapludoll) in Gongzhuling, Jilin Province, Northeast China. After cultivar calibration, the CERES-Maize model was able to simulate aboveground biomass and crop yield of in the evaluation data set (n-RMSE=5.0-14.6%), but the model still over-estimated aboveground N uptake (i.e., with E values from -4.4 to -21.3 kg N ha-~). By analyzing DSSAT equation, N stress coefficient for changes in concentration with growth stage (CTCNP2) is related to N uptake. Further sensitivity analysis of the CTCNP2 showed that the DSSAT model simulated maize nitrogen uptake more precisely after the CTCNP2 coefficient was adjusted to the field site condition. The results indicated that in addition to calibrating 6 coefficients of maize cultivars, radiation use efficiency (RUE), growing degree days for emergence (GDDE), N stress coefficient, CTCNP2, and soil fertility factor (SLPF) also need to be calibrated in order to simulate aboveground biomass, yield and N uptake correctly. Independent validation was conducted using 2008-2010 experiments and the good agreement between the simulated and the measured results indicates that the DSSAT CERES-Maize model could be a useful tool for predicting maize production in Northeast China. 展开更多
关键词 DSSAT CERES-Maize model maize growth simulation model evaluation fertilizer N experiment
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Effect of N Fertilizers on Root Growth and Endogenous Hormones in Strawberry 被引量:22
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作者 WANG Bo LAI Tao +2 位作者 HUANG Qi-Wei YANG Xing-Ming SHEN Qi-Rong 《Pedosphere》 SCIE CAS CSCD 2009年第1期86-95,共10页
Endogenous hormones play an important role in the growth and development of roots. The objective of this research was to study the effect of four types of N fertilizers on the root growth of strawberry (Fragaria anana... Endogenous hormones play an important role in the growth and development of roots. The objective of this research was to study the effect of four types of N fertilizers on the root growth of strawberry (Fragaria ananassa Duchesne) and the endogenous enzymes of indole-3-acetic acid (IAA), abscisic acid (ABA), and isopentenyl adenosine (iPA) in its roots and leaves using enzyme-linked immunosorbent assay. Application of all types of N fertilizers significantly depressed (P ≤ 0.05) root growth at 20 d after transplanting. Application of organic-inorganic fertilizer (OIF) as basal fertilizer had a significant negative effect (P ≤ 0.05) on root growth. The application of OIF and urea lowered the lateral root frequency in strawberry plants at 60 d (P ≤ 0.05) compared with the application of two organic fertilizers (OFA and OFB) and the control (CK). With the fertilizer treatments, there were the same concentrations of IAA and ABA in both roots and leaves at the initial growth stage (20 d), lower levels of IAA and ABA at the later stage (60 d), and higher iPA levels at all seedling stages as compared to those of CK. Thus, changes in the concentrations of endogenous phytohormones in strawberry plants could be responsible for the morphological changes of roots due to fertilization. 展开更多
关键词 endogenous hormone organic and inorganic N fertilizers root growth STRAWBERRY
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