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Sustainable Intensification and Large-scale Operation of Cultivated Land Use at the Farmers’ Scale:A Case Study of shandong Province,china

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Chinese Geographical science 2024年第1期34卷 149-167页

作者： LI Li LYU Xiao ZHANG Anlu NIU shandong PENG Wenlong School of Public Administration Huazhong Agricultural UniversityWuhan430070China Department of Geography University of ZurichZurich8057Switzerland School of Humanities and Law Northeastern UniversityShenyang110169China School of Geography and Tourism Qufu Normal UniversityRizhao276800China

Sustainable intensification of cultivated land use(SICLU) and large-scale operations(LSO) are widely acknowledged strategies for enhancing agricultural ***,the existing literature has faced challenges in precisely defining SICLU and constructing comprehensive indicators,which has hindered the exploration of factors influencing LSO within the SICLU *** address this gap,we integrated self-efficacy theory into the design of an index framework for evaluating *** subsequently employed econometric models to analyze the significant factors that impact *** findings reveal that SICLU can be divided into four key dimensions:intensive management,efficient output,resource conservation,and ecological environment ***,it is crucial to incorporate belief-based cognitive factors into the index system,as farmers’ understanding of fertilizer and pesticide application significantly influences their willingness to engage in ***,we identify grain market turnover as the most influential factor in promoting LSO,with single-factor contribution rates reaching 70.9% for cultivated land transfer willingness and 62.5% for the total planting ***,unlike irrigation and agricultural machinery inputs,increased labor inputs correspond to larger planting areas for *** trend may be attributed to reduced labor availability because of rural labor migration,whereas the reduction in irrigation and agricultural input is contingent on innovations in production practices and the transfer of cultivated land management ***,SICLU dynamically influences LSO,with each index related to SICLU having an optimal range that fosters *** insights offer valuable guidance for policymakers,emphasizing farmers as their central focus,with the adjustment of input and output factors as a means to achieve LSO as the ultimate *** conclusion,we propose research avenues for further enriching the SICLU framework to ensur

关键词： sustainable intensification of cultivated land use(SICLU) self-efficacy status quo bias input and output Boosted Regression Tree willingness to transfer cultivated land cultivated land planting areas shandong,china

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Study on sea water intrusion into palaeochannels on south coastal plain of the Laizhou Bay by the Bohai Sea

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Acta Oceanologica Sinica 2003年第1期22卷 69-74页

作者： Han Mei Geography Department, shandong normal university, Jinan 25.014, china shandong normal Univ Dept Geog Jinan 250014 Peoples R China

The palaeochannel evolution in the study region is divided into four stages by such methods as 14C dating. Sea water intrusion through palaeochannels has been studied as a focal point. Palaeochannels are the main passageways through which the sea water intrudes at a higher speed, through many means and in a changeable dynamic state.

关键词： Palaeochannel sea water intrusion south coastal plain of Laizhou Bay

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A Hybrid of Theorems of Goldbach and Piatetski-Shapiro

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Chinese Annals of Mathematics,Series B 2006年第3期27卷 341-352页

作者： Xianmeng MENG Mingqiang WANG School of Computer science and Technology, shandong university, Jinan 250100, china Department of Statistics and Mathematics, shandong Finance Institute, Jinan 25.014, china. School of Computer science and Technology, shandong university, Jinan 250100, china Department of Mathematics, Qufu normal university, Qufu 273165, shandong, china. School of Computer science and Technology Shandong University Jinan 250100 China Department of Statistics and Mathematics Shandong Finance Institute Jinan 250014 China Department of Mathematics Qufu Normal University Qufu 273165 Shandong China

It is proved that for almost all sufficiently large even integers n, the prime variable equation n = p1 ＋ p2, p1 ∈ Pγ is solvable, with 13/15 〈γ≤ 1, where Pγ = {p ｜p = [m^1/γ], for integer m and prime p} is t... 详细信息

关键词： Circle method Sieve method Goldbach problem

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Mutual Conversion of Land Use between Urban and Rural Area in the Process of Urbanization: A Case Study of shandong Province

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Chinese Journal of Population,Resources and Environment 2007年第2期5卷 93-96页

作者： Xu Hong college of Population, Resource and Environment, shandong normal university, Jinan shandong 25.014, china college of Population Resource and Environment Shandong Normal University Jinan Shandong 250014 China

Urbanization is one of the driving forces for the land use change in type and structure, and its prominent effect is to convert rural land to urban land. This paper takes Shan-dong Province as an example to analyze the current situation of the mutual conversion between the urban and rural areas from the aspects of the structure of land use, the decreasing tendency of the cultivated land, the changes of land use in urban and rural residential areas. It points out that cultivated land is converted to residential area land, industrial and/or mining area land. The relationship between the urban area land and the cultivated land is more direct; meanwhile, the changes of rural residential area lag behind obviously. The decrease of the cultivated land and the decline of soil quality will be the two difficult problems in the process of urbanization.

关键词： mutual conversion of land use between urban and rural areas structure of land use flow of the cultivated land

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Effect of lead on survival, locomotion and sperm morphology of Asian earthworm, Pheretima guillelmi

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Journal of Environmental sciences 2009年第5期21卷 691-695页

作者： ZHENG Rongquan, LI Canyang college of Chemistry and life science, Zhejiang normal university, Jinhua 321004, china. [a]college of Chemistry and life science Zhejiang Normal University Jinhua 321004 China

To provide basic toxicity data for formulating risk characterization benchmarks, the effects of lead on survival, locomotion, and sperm morphology were investigated in the Asian earthworm Pheretima guillelmi. The LC50 of P. guiUelmi for 7 and 14 d were 4285＋339 mg/kg and 3207＋248 mg/kg, which shows P. guillelmi can tolerate a higher concentration of lead nitrate. The average weight of the surviving earthworms decreased at concentration of 2800 mg Pb/kg soil, and the locomotor ability of earthworms exposed to a range of soil Pb concentrations showed a general decrease with increasing Pb concentrations. We also presented data depicting the sperm morphology of earthworms, which shows potential as a sensitive biomarker for measuring the effects of heavy metal on reproduction.

关键词： lead Pheretima guillelmi sperm morphology locomotion

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Lattice dynamical simulation of methane hydrate

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Journal of Natural Gas Chemistry 2010年第1期19卷 43-46页

作者： Lin Wang, Shunle Dong Physics Department, college of Information science and Engineering, Ocean university of china, Qingdao 266100, shandong, china [a] Physics Department College of Information Science and Engineering Ocean University of China Qingdao 266100 Shandong China

INS （Inelastic Neutron Scattering） spectrum of methane hydrate was measured on MARI （a direct-geometry chopper spectrometer） at Ruther-ford Appleton Laboratory, UK. Compared with ice Ih, it is found that the whole spectrum of methane hydrate moves toward high-energy by about 1.5 meV. Using lattice dynamical （LD） technique, computer simulations of methane hydrate were carried out. In the simulations, four potential models （BE TIP3P, TIP4P, MCY） were employed to calculate the phonon density of states （PDOS）. Comparing the calculated PDOS spectrum with the experimental spectrum, it is found that BF, TIP4P, and TIP3P potential lattices give out well-separated translational and librational bands while MCY potential lattice is unstable to do so and this model is not suitable to describe hydrate system.

关键词： methane hydrate inelastic neutron scattering lattice dynamical simulation

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Optical waveguides in LiNbO_3 and stoichiometric LiNbO_3 crystals by proton exchange

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science china(Physics,Mechanics & Astronomy) 2008年第10期51卷 1479-1488页

作者： LI ShiLing college of Physics and Engineering, Qufu normal university, Qufu 273165, china School of Physics and Microelectronics, shandong university, Jinan 250100, china 1. college of Physics and Engineering Qufu Normal University Qufu 273165 China 2. School of Physics and Microelectronics Shandong University Jinan 250100 China

The formation of optical planar waveguides in LiNbO3 and stoichiometric LiNbO3 crystals by proton exchange was reported. The prism-coupling method was used to characterize the dark-line spectroscopy at the wavelength of 633 and 1539 nm, re-spectively. The mode optical near-field outputs from proton-exchanged LiNbO3 and SLN waveguides at 633 nm were presented. The mode field from stoichiometric LiNbO3 (SLN) waveguide is lighter and more uniform than that from LiNbO3 waveguide, which means the quality of the waveguide in SLN crystal is better than that of the LiNbO3 waveguide. For proton-exchanged LiNbO3 waveguides, the evo-lution of the refractive index profile with annealing was presented. The disorder profiles of Nb atoms in proton-exchanged LiNbO3 waveguides were obtained by Rutherford backscattering/channeling technique. It is shown that the longer the exchange time, the larger the displacement of Nb atoms.

关键词： optical waveguide proton exchange LiNbO3 crystal stoichiometric LiNbO3 crystal

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Microbial communities in microcosm soils treated with battery waste

引用

Progress in Natural science:Materials International 2007年第8期17卷 919-926页

作者： Han Xuemei Guo Weihua Wang Renqing~(**) Wang Mengcheng (college of life sciences,shandong university,Jinan 250100,china) [a]college of life sciences Shandong University Jinan China

Battery waste is one of the most destructive hazards to our environment,especially to the *** order to understand the effects of the battery waste on the microbial communities in soil,microcosm soils were treated with the powder made from the battery *** biomass and respiration were measured after 15,30,45,and 60 days of the treatment,and catabolic capability and Bi- olog profile were determined after 60 *** biomass was declined by all treatments,while microbial respiration and catabolic ca- pability were *** microbial biomass recovered after a period of incubation,microbial respiratory quotient,catabolic capa- bility and community structure remained significantly *** results also suggest that microbial respiratory quotient and Biolog pa- rameters are more sensitive than microbial biomass to the battery stress on bioavailability.

关键词： battery waste Biolog heavy metals microbial biomass respiratory quotient soil microcosm

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Investigation on the Surface Coating of Grinding Balls

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Rare Metals 2001年第4期20卷 259-264页

作者： Chengguo Wang1 Yujun Bai1.2 1) college of Materials science and Engineering, shandong university, Jinan 250061, china 2) Mechanical Department. shandong university of science and Technology. Jinan 25003), china shandong Univ Coll Mat Sci & Engn Jinan 250061 Peoples R China Shanghai Univ Sci & Technol Dept Mech Jinan 250031 Peoples R China

The surface coating of grinding balls was investigated experimentally. The results show that a coating may form on the surface of grinding balls when Cr or Al powders are subjected to ball grinding. The plastic deformation of the ball surface plays an important role during the coating formation, and the strong binding force between the powders and the balls is a necessary pre-condition. The thickness of coating increases with the plasticity of the powders and the balls. Annealing the balls with coating will result in an obvious diffusion of the elements in the bonding zone of interface.

关键词： coating ball grinding plastic deformation

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ON THE LEAST SQUARES PROBLEM OF A MATRIXEQUATION

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Journal of Computational Mathematics 1999年第6期17卷 589-594页

作者： An-ping Liao(college of science, Hunan normal university, Changsha 410081, china) Hunan normal Univ Coll Sci Changsha 410081 Peoples R China

Least squares solution of F=PG with respect to positive semidefinite symmetric P is considered,a new necessary and sufficient condition for solvablity is given,and the expression of solution is derived in the some special cases. Based on the expression, the least spuares solution of an inverse eigenvalue problem for positive semidefinite symmetric matrices is also given.

关键词： least squares solution matrix equation inverse eigenvalue problem positive semidefinite symmetric matrix

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