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Characterizing historical(1992–2010) transitions between grassland and cropland in mainland France through mining land-cover survey data

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Journal of Integrative Agriculture 2015年第8期14卷 1511-1523页

作者： ying Xiao Catherine Mignolet Jean-Fran?ois Mari Marc Beno?t INRA SAD UPR 055 ASTER 662 Avenue Louis BuffetMirecourt 88500 France Université de Lorraine LORIA UMR 7503Vandoeuvre-lès-Nancy 54506 France

Grassland, as one of the largest ecosystems on the earth, supports various goods and services to ***, humans have increased agricultural output primarily by cropland expansion and agricultural *** cropland area was primarily gained at the expense of grassland and *** from grassland conversion, increasing consumption of calorie- and meat-intensive diets drives the intensification of livestock systems, which is shifting steadily from grazing to feeding with *** cope with the environmental degradation due to agriculture, various forms of ‘green payment＇ were implemented to promote the adoption of sustainable farming practices over the last two decades in the European *** aim of this study is to monitor the recent transitions（1992–2010） between grassland and cropland during two Common Agricultural Policy（CAP） reforms at the French mainland *** proposed an innovative approach to link grassland conversion to agricultural commodities and farming systems *** first assessed the grassland-to-cropland conversion and further investigated the crop sequence patterns that were observed to be dominant after the conversion through mining land-cover survey data Teruti and *** found the trends of the transitions between grassland and cropland over the two time intervals： The loss of grassland（1992–2003） and restoration or re-expansion of grassland（2006–2010） in mainland *** finding on the crop sequence patterns after the grassland conversion reveals two notable evolutions of agricultural production *** evolutions were related to the increase in the proportion of cropland in the total agricultural land *** evolution was most likely influenced by the demand for fodder： The conversion from grazing livestock to feeding *** evolution was the conversion from livestock production to field crop *** results indicate that the intensification of livestock farming systems

关键词： conversion crop sequence patterns land-cover survey agricultural land-use change

Element-wise representations with ECNet for material property prediction and applications in high-entropy alloys

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npj Computational Materials 2022年第1期8卷 2409-2418页

作者： Xinming Wang Nguyen-Dung Tran Shuming Zeng Cong Hou ying Chen Jun Ni State Key Laboratory of Low-Dimensional Quantum Physics Department of PhysicsTsinghua UniversityBeijing100084China Frontier Science Center for Quantum Information Beijing100084China Fracture and Reliability Research Institute School of EngineeringTohoku University6-6-01 AramakiaobaAobakuSendai980-8579Japan College of Physics Science and Technology Yangzhou UniversityYangzhou225002China Collaborative Innovation Center of Quantum Matter Beijing100084China

When developing deep learning models for accurate property prediction,it is sometimes overlooked that some material physical properties are insensitive to the local atomic ***,we propose the elemental convolution neural networks(ECNet)to obtain more general and global element-wise representations to accurately model material *** shows better prediction in properties like band gaps,refractive index,and elastic moduli of *** explore its application on high-entropy alloys(HEAs),we focus on the FeNiCoCrMn/Pd systems based on the data of DFT *** knowledge from less-principal element alloys can enhance performance in HEAs by transfer learning ***,the element-wise features from the parent model as universal descriptors retain good accuracy at small data *** this framework,we obtain the concentration-dependent formation energy,magnetic moment and local displacement in some sub-ternary and quinary *** results enriched the physics of those high-entropy alloys.

关键词： alloys prediction entropy

Storage and transfer of optical excitation energy in GaInP epilayer:Photoluminescence signatures

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Journal of Materials Science & Technology 2019年第7期35卷 1364-1367页

作者： Shijie Xu ying Huang Zhicheng Su Rongxin Wang Jianrong Dong Deliang Zhu Department of Physics and Shenzhen Institute of Research and Innovation (HKU-SIRI)The University o f Hong KongPokfulam RoadHong KongChina Vacuum Interconnected Nanotech Workstation Suzhou Institute of Nano-tech and Nano-bionicsChinese Academy of SciencesSuzhou215123China Guangdong Research Center for Interfacial Engineering of Functional Materials and College of Materials Science and EngineeringShenzhen UniversityShenzhen518060China

GaInP alloy could be the most trusted key material for fabricating super-high-efficiency single-and multijunction solar cells, especially for space applications. The storage and transfer of optical excitation energy in this key alloy is thus a key subject of the energy conversion from optical to electrical. In this article we present a study of the subject through investigating photoluminescence(PL) degradation in the GaInP epilayer at 4 K under the continuous optical excitations of ultraviolet(UV) 325 nm, visible 488.0 and 514.5 nm lasers. It is found that the decline of PL intensity with the irradiation time may be represented by I(t)/I0=(1 + tτ-1)-1+C, where I0 is the luminescence intensity at the beginning of irradiation, a time constant, and C a background. Moreover, the PL degradation degree reduces with increasing the excitation wavelength. In addition, some red shift of the PL peak is observed accompanying with the intensity decline under the UV laser excitation. These PL signatures indicate that the localized carriers within the local atomic ordering domains play a major role in the storage and transfer of the excitation energy via photon recycling processes.

关键词： GaInP alloy Photoluminescence Energy transfer Photon recycling

A Joint Laplace Transform for Pre-exit Diffusion of Occupation Times

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Acta Mathematica Sinica,English Series 2017年第4期33卷 509-525页

作者： Ye CHEN Xiang Qun YANG ying Qiu LI Xiao Wen ZHOU College of Mathematics and Computer Science Hu'nan Normal University College of Mathematics and Computational Science Hu’nan University of Arts and Science College of Mathematics and Statistics Changsha University of Science and Technology Department of Mathematics and Statistics Concordia University

For a < r < b, the approach of Li and Zhou(2014) is adopted to find joint Laplace transforms of occupation times over intervals(a, r) and(r, b) for a time homogeneous diffusion process before it first exits from eithe... 详细信息

For a ying these results, we obtain more explicit expressions on the joint Laplace transforms of occupation times for Brownian motion with drift, Brownian motion with alternating drift and skew Brownian motion, respectively.

关键词： Laplace transform occupation time time-homogeneous diffusion exit time Brownian motion with alternating drift skew Brownian motion

Simulation Study on the Extension of Semi-flexible Polymer Chains in Cylindrical Channel

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Chinese Journal of Polymer Science 2019年第12期37卷 1290-1297,I0008页

作者： Yu Fu Fan Wu Jian-Hua Huang ying-Cai Chen Meng-Bo Luo Zhejiang Province Key Laboratory of Quantum Technology and Device Department of PhysicsZhejiang UniversityHangzhou 310027China Department of Chemistry Zhejiang Sci-Tech UniversityHangzhou 310018China Department of Physics Taizhou UniversityTaizhou 318000China

The scaling relations among the mean end-to-end distance of polymer along the channel,the polymer length N,and the effective diameter of channel De were investigated for flexible and semi-flexible polymer chains confined in long cylindrical *** the flexible polymer chain,scaling relation~NDe–0.7 was found in the classic de Gennes regime at lp2/b~NDe–1 in the transition regime lp1)and~De–0.7 in the classic de Gennes regime at larger De>xlp were *** simulation results revealed that the scaling relation in the transition regime was due to the rod-like behavior of the semi-flexible polymer in the small regime lp

关键词： Semi-flexible polymer Cylindrical channel Conformation Scaling relation Monte Carlo simulation

Effect of hydrogen annealing on characteristics of polycrystalline silicon

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Rare Metals 2006年第Z1期25卷 173-175页

作者： GOU Xianfang XU ying LI Xudong HENG Yang MA Lifen REN Bingyan Beijing Solar Energy Research Institute Beijing 100083 China Beijing Solar Energy Research Institute Beijing 100083 China Beijing Solar Energy Research Institute Beijing 100083 China Beijing Solar Energy Research Institute Beijing 100083 China Beijing Solar Energy Research Institute Beijing 100083 China Institute of Information Function Materials Hebei University of Technology Tianjin 300130 China

The characteristics of mc-Si used for solar cells during H2 ambient annealing at 800-1200 ℃ were investigated by means of FTIR and QSSPCD. The results reveal that grain boundaries or defects in mc-Si may facilitate the formation of oxygen precipitates, and the formation of oxygen precipitates has deleterious effect on the lifetime of mc-Si. Decreasing lifetime could result from the formation of new recombination during annealing. Additionally, It is found that hydrogen may facilitate the formation of oxygen precipitates in mc-Si. On the other hand, the diffusion of hydrogen may passivate the defects/boundaries and it is beneficial to the lifetime of mc-Si.

关键词： multi-crystalline silicon oxygen and carbon minority carrier lifetime annealing

Study on Numerical Comparison Method of Four-bar Straight-line Guidance Mechanism

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Journal of Harbin Institute of Technology(New Series) 2013年第4期20卷 63-72页

作者： Hong-ying Yu Yan-Wei Zhao Zhi-Xing Wang School of Mechanical Engineering Harbin Institute of Technology

In order to solve four-bar straight-line guidance mechanism synthesis problem for the arbitrarily given straight-line’s"angle requirement"and"point-position requirement",a numerical comparison synthesis method for single and double straight-line guidance mechanism is presented,which is convenient to realize by computer *** basic idea of this method is:to select a four-bar linkage whose relative bar length of crank is 1 as a basic four-bar *** the other three relative bars’length is changed,and a lot of basic four-bar linkage can be *** are many single and double ball-points of each basic four-bar *** the motion of a basic four-bar linkage,there is straight-line segment of each Ball-point’s *** data of these basic four-bar linkages is saved to a *** designing a four-bar straight-line guidance mechanism,the design data is compared with the data in database and a satisfactory four-bar linkage can be *** method effectively solves the straight-line guidance mechanism synthesis problem.

关键词： numerical method straight-line guidance mechanism mechanism synthesis

Short-term efficacy and influencing factors of conventional chemotherapy combined with irinotecan in patients with advanced gastric cancer

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World Journal of Gastrointestinal Oncology 2023年第1期15卷 143-154页

作者： Jun-Ping Wang Jian-Lei Du Ya-ying Li Pharmacy Department Zhumadian Central HospitalZhumadian 463000Henan ProvinceChina

BACKGROUND Gastric cancer is one of the most common cancers worldwide, with a 5-year survival rate of only 20%. The age of onset of gastric cancer is in line with the general rule of cancer. Most of them occur after middle age, mostly between 40and 60 years old, with an average age of about 50 years old, and only 5% of patients are under 30 years old. The incidence of male is higher than that of *** To investigate the short-term efficacy and influencing factors of chemotherapy combined with irinotecan in patients with advanced gastric *** Eighty patients with advanced gastric cancer who were treated in our hospital from January 2019 to January 2022 were selected. The patients were divided into an observation group(n = 40) and control group(n = 40) by the envelope *** control group was given preoperative routine chemotherapy. The observation group was treated with irinotecan in addition to the chemotherapy given to the control group. The short-term efficacy of treatment in the two groups, as well as tumor marker levels and quality of life before and after treatment were *** The short-term treatment effect in the observation group was better than that in the control group(P < 0.05), and the total effective rate was 57.50%. The age and proportion of tumor node metastasis(TNM) stage IV patients with ineffective chemotherapy in the observation group were(65.12 ± 5.71) years and 52.94%,respectively, which were notably higher than those of patients with effective chemotherapy(P < 0.05), while the Karnofsky Performance Scale score was(67.70± 3.83) points, which was apparently lower than that of patients with effective chemotherapy(P <0.05). After 3 mo of treatment, the SF-36 scale scores of physiological function, energy, emotional function, and mental health in the observation group were 65.12 ± 8.14, 54.76 ± 6.70, 47.58 ± 7.22,and 66.16 ± 8.11 points, respectively, which were considerably higher than those in the control group(P < 0.

关键词： Advanced gastric cancer Conventional chemotherapy Irinotecan Efficacy Quality of life

Suppression of Spiral Waves and Spatiotemporal Chaos Under Local Self-adaptive Coupling Interactions

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Communications in Theoretical Physics 2006年第1期45卷 121-126页

作者： MA Jun WU Ning-Jie ying He-Ping YUAN Li-Hua Department of Physics School of Science Lanzhou University of Technology Lanzhou 730050 China Zhejiang Institute of Modern Physics Zhejiang University Hangzhou 310027 China

In this paper, a close-loop feedback control is imposed locally on the Fitzhugh-Nagumo （FHN） system to suppress the stable spirals and spatiotemporal chaos according to the principle of self-adaptive coupling interaction. The simulation results show that an expanding target wave is stimulated by the spiral waves under dynamic control period when a local area. of 5 × 5 grids is controlled, or the spiral tip is driven to the board of the system, It is also found that the spatiotemporal chaos can be suppressed to get a stable homogeneous state within 50 time units as two local grids are controlled mutually. The mechanism of the scheme is briefly discussed.

关键词： spiral waves spatiotemporal chaos close-loop feedback Fitzhugh-Nagumo (FHN) equation