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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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Morphology and electrical conductivity of PACS

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Journal of Environmental Sciences 2000年第3期12卷 319-324页

作者： GAO Bao\|yu\+1, LIU Zong\|gang\+2. YUE Qin\|yan\+3. ZHAO Hua\|zhang\+3.(1. Department of Environmental Engineering, shandong university, Jinan 2.0100, China 2. Environmental Monitoring Station of Huaiyin, Jinan 2.002., China 3. Department of Environ 山东大学山东济南 2 50 1 0 0 山东济南市槐荫区环境监测山东济南 2 50 0 2 2

Polyaluminium chlorides with sulfate ion(PACS) were prepared by using AlCl 3.6H 2., Al(SO 4) 3.18H 2. and Na 2.O 3.as raw materials. The effects of basicity ( r ), Al 3. /SO 4 2. molar ratio and aging time on the morphology of PACS were observed by transmission electrical microscope. The influence of aging time on charge neutralization and coagulation effect of PACS was studied. The effects of basicity ( r ), Al 3. /SO 4 2. molar ratio and aging time on the electrical conductivity of PACS solution were also investigated. The experimental results show that the degree of polymerization of polyaluminium chloride(PAC) increases when SO 4 2. ion is added. The higher the basicity( r ) and the longer the aging time, the larger the size of polymer PACS. The ability of PACS neutralizing the charge on Kaolinite decreases with the increase of aging time. The electrical conductivity of PACS solution(the concentration of Al 3. ion is 0.18 mol/L) with different aging time is the function of the basicity and Al 3. /SO 4 2. molar ratios and has its maximum at r =0.5 and Al 3. /SO 4 2. =12.

关键词： coagulant PACS morphology transmission electron microscope electrical conductivity coagulation

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The optical near-field speckles and their first order statistics on the basis of the integral equations of electromagnetic field

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Science China(Physics,Mechanics & Astronomy) 2004年第3期47卷 365-380页

作者： CHENG Chuanfu1, 2. SONG Hongsheng2. LIU Chunxiang2. REN Xiaorong2. ZHANG Ningyu3. TENG Shuyun1 & XU Zhizhan1 1. Shanghai Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, P. O. Box 800-2.1, Shanghai 2.1800, China 2. Department of Physics, shandong Normal university, Jinan 2.0014, China 3. shandong Institute of Architecture and Engineering, Jinan 2.0014, China 1. Shanghai Institute of Optics and Fine Mechanics Chinese Academy of Sciences P. O. Box 800-211 201800 Shanghai China 2. Department of Physics Shandong Normal University 250014 Jinan China 3. shandong Institute of Architecture and Engineering 250014 Jinan China

From Helmholtz equation of the harmonic electromagnetic waves, the integral equations of the light field at the medium boundaries are obtained by use of the Green's theorem and are discretized into linear equation set with the values of the light field and its derivative as the unknowns. On solving the linear equation set, we realize the rigorous computations of the light fields at the boundaries. Then the intensities of the light waves scattered by the random self-affine fractal surfaces in the optical near-field are calculated, and the propagation characteristics, the evolutions of the contrast and the intensity probability density function of the near-field speckles are studied in detail. The near-field speckles are much different from the conventional speckles in the diffraction regions and in the imaging systems. There are obvious local fluctuations in the intensity distributions of the near-field speckles and such fluctuations disappear after propagating a distance of one wavelength from the medium surfaces. For the random surfaces with smaller lateral correlation lengths, the speckle contrasts approach the saturation values and the speckle fields approach Gaussian distribution within the near-field, while for the random surfaces with larger lateral correlation lengths, such evolutions become comparatively slow.

关键词： speckle, near-field optics, first order statistics, Green's function.

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Analysis on cohesive crack opening displacement considering the strain softening effect

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Science China(Physics,Mechanics & Astronomy) 2006年第1期49卷 88-101页

作者： WANG Limin1, XU Shilang2.& ZHAO Xiqiang3.1. Mechanics Department, shandong university of Technology, Zibo 2.5049, China 2. Civil Engineering Department, Dalian university of Technology, Dalian 11602., China 3. Mathematics Department, Ocean university of China, Qingdao 2.6071, China Mechanics Department Shandong University of Technology Zibo 255049 China Civil Engineering Department Dalian University of Technology Dalian 116024 China Mathematics Department Ocean University of China Qingdao 266071 China

In order to investigate the crack propagation in quasi-brittle materials like rock, ceramic and concrete, Hillerborg and his co-researchers abstracted the fracture process zone in front of a stress free crack in terms of a “fictitious crack zone”. On the fictitious crack zone, cohesive stresses distribute following a given softening relationship of stress vs. crack opening. Based on the polynomial or power series expression of cohesive crack opening displacement, the relationship of the cohesive stress vs. the crack opening displacement is established using elastic theory and integral equation, and some unknown physics variables are obtained using variation approach. The calculation results gained in this paper are close to the experimentally test ones.

关键词： cohesive crack, softening, dissipation work, variation approach.

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Bionic Design and Finite Element Analysis of Elbow in Ice Transportation Cooling System

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Journal of Bionic Engineering 2010年第3期7卷 301-306页

作者： Dejun Miao~(1,2., Xiuhua Sui~3. Linjing Xiao~3.1. Key Laboratory of Mine Hazard Prevention and Control (Ministry of Education, China), shandong university of Science and Technology, Qingdao 2.6510, P. R. China 2. School of Architecture, Tsinghua university, Beijing 100084, P. R. China 3. College of Mechanical and Electronic Engineering, shandong university of Science and Technology, Qingdao 2.6510, P. R. China [a] Key Laboratory of Mine Hazard Prevention Control (Ministry of Education China) Shandong University of Science Technology Qingdao 266510 P. R. China [b] School of Architecture Tsinghua University Beijing 100084 P. R. China [c] College of Mechanical Electronic Engineering Shandong University of Science Technology Qingdao 266510 P. R. China

With the increase in mining depth, mine heat harm has appeared to be more prominent. The mine heat harm could be resolvedor reduced by ice refrigeration. Thus, ice transportation through pipeline becomes a critical problem; typically flowresistance occurs in the elbow. In the present study, according to the analysis of the surface morphology of fish scale, abiomimetic functional surface structure for the interior wall of elbow is designed. Based on the theory of liquid-solid two phaseflow, a CFD numerical simulation of ice-water mixture flowing through the elbow is carried out using finite element *** experiments of pressure drop and flow resistance for both bionic and common elbows are conducted to test theeffect of the bionic elbow on flow resistance reduction. It is found that with the increase in the ice mass fraction in the ice-watermixture, the effect of bionic elbow on resistance reduction becomes more obvious.

关键词： bionic elbow two phase flow ice transportation flow resistance reduction pressure loss

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Development and evaluation of an online monitoring single-particle optical particle counter with polarization detection

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Journal of Environmental Sciences 2024年第4期138卷 585-596页

作者： Weijie Yao Xiaole Pan Yu Tian Hang Liu Yuting Zhang shandong Lei Junbo Zhang Yinzhou Zhang LinWu Yele Sun Zifa Wang State Key Laboratory of Atmospheric Boundary Layer Physics and Atmospheric Chemistry Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China College of Earth and Planetary Sciences University of Chinese Academy of SciencesBeijing 100049China Center for Excellence in Regional Atmospheric Environment Institute of Urban EnvironmentChinese Academy of SciencesXiamen 361021China

We developed a single-particle optical particle counter with polarization detection(SOPC)for the real-time measurement of the optical size and depolarization ratio(defined as the ratio of the vertical component to the parallel component of backward scattering)of atmospheric particles,the polarization ratio(DR)value can reflect the irregularity of the *** SOPC can detect aerosol particles with size larger than 500 nm and the maximum particle count rate reaches~1.8×10^(5)particles per *** SOPC uses a modulated polarization laser to measure the optical size of particles according to forward scattering signal and the DR value of the particles by backward S and P signal *** sampling rate of the SOPC was 106#/(sec·channel),and all the raw data were processed *** calibration curve was obtained by polystyrene latex spheres with sizes of 0.5-10μm,and the average relative deviation of measurement was 3.96% for sub 3.m particles.T-matrix method calculations showed that the DR value of backscatter light at 12.°could describe the variations in the aspect ratio of particles in the above size *** performed insitu observations for the evaluation of the SOPC,the mass concentration constructed by the SOPC showed good agreement with the PM_(2.5)measurements in a nearby state-controlled monitoring *** instrument could provide useful data for source appointment and regulations against air pollution.

关键词： Instrument development Single particle detection Measurement uncertainty Optical simulation Mass concentration

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Flatness and Profile Integration Control Model for Tandem Cold Mills

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Journal of Iron and Steel Research International 2012年第3期19卷 31-37页

作者： SHAN Xiu-ying1,2.3. LIU Hong-min1,2. JIA Chun-yu1,2. SUN Jian-liang1,2.(1. Engineering Research Center of Rolling Equipment and Complete Technology of Ministry of Education, Yanshan university, Qinhuangdao 066004, Hebei, China 2. State Key Laboratory of Metastable Materials Science and Technology, Yanshan university, Qinhuangdao 066004, Hebei, China 3. Hot Tandem Rolling Factory, Jinan Iron and Steel Co Ltd, Jinan 2.0101, {2., China) [a] Engineering Research Center of Rolling Equipment and Complete Technology of Ministry of Education Yanshan University Qinhuangdao 066004 Hebei China [b] State Key Laboratory of Metastable Materials Science and Technology Yanshan University Qinhuangdao 066004 Hebei China [c] Hot Tandem Rolling Factory Jinan Iron and Steel Co Ltd Jinan 250101 Shandong China

Using the effective matrix methods of flatness and profile control synthetically, the flatness and profile in- tegration control scheme for tandem cold mills is built in order to increase flatness and profile control precision of tan- dem cold mills. Corresponding control strategies are adopted for various control objectives of different stands and the coordination control strategies of various stands are given, which makes the on-line flatness control cooperate with on-line profile control and implements the parallel control of different stands. According to the measured flatness and profile data of some 1550 mm tandem cold mills, the control scheme is verified and the result indicates that the scheme has high flatness and profile control precision with steady and reliable control process. A new way and method is supplied for researching shade control of tandem cold mills.

关键词： flatness profile shape effective matrix tandem cold mill

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Sol-gel preparation and spectroscopic study of the pyrophanite MnTiO_3.nanoparticles

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Science China Chemistry 2005年第3期48卷 210-215页

作者： ZHOU Guowei1, KANG Youngsoo2. LI Tianduo1 & XU Guiying3.1. School of Light Chemicals and Environmental Engineering, shandong Institute of Light Industry, Jinan 2.0100, China 2. Department of Chemistry, Pukyong National university, Daeyeon-3.dong, Nam-gu, Pusan 608-73., Korea 3. Key Laboratory for Colloid and Interface of Ministry of Education of China, shandong university, Jinan 2.0100, China 1. School of Light Chemicals and Environmental Engineering Shandong Institute of Light Industry 250100 Jinan China 2. Department of Chemistry Pukyong National University Daeyeon-3-dong Nam-gu 608-737 Pusan Korea 3. Key Laboratory for Colloid and Interface of Ministry of Education of China Shandong University 250100 Jinan China

The nanosized xerogel of titanium dioxide (TiO2. and manganese oxides (MnO2. Mn2.3. Mn3.4) was prepared by the sol-gel method using manganese chloride (MnCl2.4H2.) and titanium isopropoxide (Ti(O-iPr)4) as precursors in cetyltrimethylammonium bromide (CTAB)/ ethanol/H2./HCl micelle solutions, following the calcinations of the produced powders at differ-ence temperatures. The nanostructure and phase composition of these nanoparticles were characterized with X-ray powder diffraction (XRD), transmission electron microscopy (TEM), en-ergy dispersive X-ray spectroscopy (EDX) and X-ray photoelectron spectroscopy (XPS). The spectroscopic characterizations of these nanoparticles were also done with UV-Vis spectroscopy and laser Raman spectroscopy (LRS). XRD patterns show that the pyrophanite MnTiO3.phase was formed at the calcinations temperature of 900℃. The TEM images show that the nanoparti-cles are almost spherical or slight ellipose and the sizes are 50 nm on average. The UV-Vis spectra show that the nanosized MnTiO3.have significant absorption bands in the visible region. There are new absorption peaks of MnTiO3.nanoparticles in LRS compared with the pure TiO2.powder.

关键词： pyrophanite MnTiO3. nanoparticles, spectroscopy, CTAB micelle, sol-gel.

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The dynamical properties of Rydberg hydrogen atom near a metal surface

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Science China(Physics,Mechanics & Astronomy) 2005年第6期48卷 667-675页

作者： GE Meihua1, ZHANG Yanhui1, WANG Dehua2. DU Mengli3.& LIN Shenglu1 1. College of Physics and Electronics, shandong Normal university, Jinan 2.0014, China 2. Department of Mathematics and Physics, shandong Institute of Architecture and Engineering, Jinan 2.0014, China 3. Institute of Theoretical Physics, Chinese Academy of Sciences, Beijing 100080, China 1. College of Physics and Electronics Shandong Normal University 250014 Jinan China 2. Department of Mathematics and Physics Shandong Institute of Architecture and Engineering 250014 Jinan China 3. Institute of Theoretical Physics Chinese Academy of Sciences 100080 Beijing China

The dynamical properties of Rydberg hydrogen atom near a metal surface are presented by using the methods of phase space analysis and closed orbit theory. Transforming the coordinates of the Hamiltonian, we find that the phase space of the system is divided into vibrational and rotational region. Both the Poincaré surface of section and the closed orbit theory verify the same conclusion clearly. In this paper we choose the atomic principal quantum number as n = 2.. The dynamical character of the exited hydrogen atom depends sensitively on the atom-surface distance d. When d is sufficiently large, the atom-surface potential can be expressed by the traditional van der Waals force and the system is integrable. When d becomes smaller, there exists a critical value dc. For d > dc, the system is near-integrable and the motion is regular. While chaotic motion appears for d < dc, and the system tends to be non-integrable. The trajectories become unstable and the electron might be captured onto the metal surface.

关键词： Rydberg hydrogen atom, van der Waals interaction, Poincaré surface of section, closed orbit theory, chaos.

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Israeli Water Achievements Today and Enlightenment to China

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Chinese Journal of Population,Resources and Environment 2008年第4期6卷 72-77页

作者： Sun Lei1,2. Xu Lanqing3.1. Institute of Environmental Science and Engineering, Ocean university of China, Qingdao shandong 2.6100, China 2. Department of Soil and Water Sciences, Faculty of Agricultural, Food and Environmental Quality Sciences, the Hebrew university of Jerusalem, 76100, Israel 3. Logistics Group of Ocean university of China, Qingdao shandong 2.6100, China Institute of Environmental Science and Engineering Ocean University of China Qingdao Shandong 266100 China Department of Soil and Water Sciences Faculty of Agricultural Food and Environmental Quality Sciences the Hebrew University of Jerusalem 76100 Israel Logistics Group of Ocean university of China Qingdao Shandong 266100 China

Despite the endemic drought, arid climate and associated limited freshwater resources, as well as difficult geopolitical realities, Israel can provide a reliable supply of high quality water to a rapidly growing population. The achievements of water supply in Israel can be summarized as water technologies (like water transportation and purification, desalination, wastewater treatment, effluent reuse, storm water catchment, control systems, rain enhancement and drip irrigation, etc.), water management and legislation as well as water industry. In view of the national concern regarding the quality and quantity of the water, the skills, technologies and know-how that Israel has accumulated in water supply and irrigation can give us enlightenment that is also presented in this paper.

关键词： Israel China water technology water management water industry

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