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One-pot synthesis of 7-aryl-11,12-dihydrobenzo[h]pyrimido-[4,5-b]quinoline-8,10(7H,9H)-diones via three-component reaction in ionic liquid

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Chinese Chemical Letters 2010年第12期21卷 1435-1438页

作者： hong yun Guo Yi Yu College of Chemical Engineering and Materials Zhejiang University of Technology Hangzhou 310014 China

A series of new 7-aryl-11,12-dihydrobenzo[h]pyrimido-[4,5-b]quinoline-8,10（7H,9H）-diones were synthesized via three-component reaction of aldehydes,l-naphthylamine and barbituric acid in ionic *** method provided se... 详细信息

关键词： Aldehyde 1-Naphthylamine Barbituric acid Ionic liquid

Farmers’Character and Behavior of Fertilizer Application-Evidence from a Survey of Xinxiang County,Henan Province,China

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Agricultural Sciences in China 2009年第10期8卷 1238-1245页

作者： HAN hong-yun ZHAO Lian-ge Center for Agricultural and Rural Development Zhejiang University Hangzhou 310029 P.R.China College of Economics Zhejiang Gongshang University Hangzhou 310035 P.R. China

Agricultural chemical use has caused a public concern over environmental issue while decisions about applying chemicals are made by individual farmers. The critical decision-making role of farmers relative to agricultural chemical use creates a need for accurate information on their perceptions of various chemical-related hazards and the factors that may influence such judgments. Based on data collected from 177 land operators at Xinxiang County in Henan Province of China, an empirical analysis is conducted to examine the relationship between farmers＇ character and the behavior of fertilizer application. Study findings reveal that： the characteristics of household head and household, and the nature of farming management positively affect the amount of fertilizers applied; information on fertilizers and the knowledge about environmental impact of fertilizer application have negative impacts by contrast. To formulate effective pollution control policies at the farm level, it is imperative for policy-makers to convey information to producers by demonstration projects, technical assistance, and education programs. Under a changed political environment, some combination of education and economic incentives could be lower cost and more effective tools for achieving desired environmental conservative goals.

关键词： nonpoint-pollution farmers' decision fertilizer application

Texture evolution behavior and anisotropy of 2A97 Al-Li alloy during recrystallization at elevated temperature

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Rare Metals 2023年第9期42卷 3139-3149页

作者： Dong Wang Chong Gao hong-yun Luo Yong-hong Yang Yue Ma School of Materials Science and Engineering Beihang UniversityBeijing100191China China Alco Research Institute of Science and Technology Beijing100082China Xi’an Aerospace Propulsion Institute Xi’an National Civil Aerospace Industrial BaseXi’an710100China

2A97 Al-Li alloy was cold-rolled to 2 mm and then thermally exposed at different temperatures for 1 h and at 723 K for different time,*** texture evolution behavior and the anisotropy of 2A97 Al-Li alloy were *** result shows that the{001}and{011}textures are the dominant recrystallization ***{124}texture is the final recrystallization *** case of low-temperature thermal exposure(473,573 K),the{011}texture is aggregated to the{112}and{123}*** the recrystallization at 723 K,the{001},{111}and{011}textures are the intermediate transition grain *** concurrent precipitation of Al_(20)Cu_(2)Mn_(3)and Al_(3)Zr results in the occurrence of unusually sharp{011}and{001}texture components during *** alloy with both recrystallization and deformation texture possesses the smallest anisotropic,and the texture is the direct reason that results in the anisotropy.

关键词： Al-Li alloy 2A97 Crystallographic texture Texture evolution Anisotropy

Two-Variable Hermite Polynomial Excitation of Two-Mode Squeezed Vacuum State as Squeezed Two-Mode Number State

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Communications in Theoretical Physics 2008年第10期50卷 965-970页

作者： HU Li-yun FAN hong-Yi Department of Physics Shanghai Jiao Tong University Shanghai 200030 China

We find that the squeezed two-mode number state is just a two-variable Hermite polynomial excitation of thetwo-mode squeezed vacuum state (THPES).We find that the Wigner function of THPES and its marginal distributionsare just related to two-variable Hermite polynomials (or Laguerre polynomials) and that the tomogram of THPES canbe expressed by one-mode Hermite polynomial.

关键词： Two variable Hermite polynomial excitation state Wigner function marginal distribution tomgram

Variation of singularity of earthquake-size distribution with respect to tectonic regime

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Geoscience Frontiers 2018年第2期9卷 453-458页

作者： Qiu-Ming Cheng hong-yun Sun State Key Lab of Geological Processes and Mineral Resources China University of Geosciences State Key Lab of Geological Processes and Mineral Resources China University of GeosciencesWuhan

Frequency-size relation of earthquakes in a region can be approximated by the Gutenberg-Richter law(GR). This power-law model involves two parameters: a-value measuring seismic activity or earthquake productivity, and b-value describing the relation between frequencies of small and large *** spatial and temporal variations of these two parameters, especially the b-value, have been substantially investigated. For example, it has been shown that b-value depends inversely on differential stress. The b-value has also been utilized as earthquake precursor in large earthquake ***, the physical meaning and properties of b-value including its value range still remain as an open fundamental question. We explore the property of b-value from frequency-size GR model in a new form which relates average energy release and probability of large earthquakes. Based on this new form of GR relation the b-value can be related to the singularity index(1-2/3 b) of fractal energy-probability power-law model. This model as applied to the global database of earthquakes with size M ≥ 5 from 1964 to 2015 indicates a systematic increase of singularity from earthquakes occurring on mid-ocean ridges, to those in subduction zones and in collision zones.

关键词： Fractals Singularity Power-law distribution Plate tectonics Mathematical model Spatial distribution

Reduction of Elemental Selenium by Samarium Diiodide: the Synthesis of Dithiodiselenides and Dithioselenides

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Chinese Chemical Letters 2001年第5期12卷 379-382页

作者： hong yun GUO yun Fa ZHENG Yong Min ZHANG Department of Chemistry Zhejiang University at Xixi CampusHangzhou 310028 Department of Chemistry Zhejiang Normal UniversityJinhua 321004 Department of Chemistry Lishui Teachers CollegeZhejiang 323000

The reduction of elemental selenium by samarium diiodide led to selective formation of selenolate anion species (Se-2(2-) and Se2-), these nucleophilic species reacted readily with sodium alkyl thiosulfates to afford ... 详细信息

关键词： Synthesis samarium diiodide dithiodiselenides dithioselenides.

Quantum Optical Squeezing Transform for Generalizing Fractional Fourier Transform

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Communications in Theoretical Physics 2008年第10期50卷 951-954页

作者： HU Li-yun FAN hong-Yi Department of Physics Shanghai Jiao Tong University Shanghai 200030 China

By establishing the relation between the optical scaled fractional Fourier transform （FFT） and quantum mechanical squeezing-rotating operator transform, we employ the bipartite entangled state representation of two-mode squeezing operator to extend the scaled FFT to more general cases, such as scaled complex FFT and entangled scaled FFT. The additiyity and eigenmodes are presented in quantum version. The relation between the scaled FFT and squeezing-rotating Wigner operator is studied.

关键词： squeezing transform scaled fractional Fourier transform IOWP technique

Brownian Motion of a Test Particle with a Normal Classical Velocity in Spacetime with a Plane Boundary

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Communications in Theoretical Physics 2007年第5期47卷 847-850页

作者： FU Xiang-yun YU hong-Wei Department of Physics and Institute of Physics Hunan Normal University Changsha 410081 China

We study the random motion of a charged test particle with a normal classical constant velocity in a spacetime with a perfectly reflecting plane boundary and calculate both the velocity and position dispersions of the test particle. Our results show that the dispersions in the normal direction are weakened while those in the parallel directions are strengthened as compared to the classical static case when the test particle classically moves away from the boundary. However, if the classical motion reverses its direction, then the dispersions in the normal direction are reinforced while those in the parallel directions get weakened.

关键词： Brownian motion vacuum fluctuation quantum field theory

Entropy method for determination of weight of evaluating indicators in fuzzy synthetic evaluation for water quality assessment

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Journal of Environmental Sciences 2006年第5期18卷 1020-1023页

作者： ZOU Zhi-hong yun Yi SUN Jing-nan School of Economics and Management Beihang University Beijing 100083 China

Considering the difficulty of fuzzy synthetic evaluation method in calculation of the multiple factors and ignorance of the relationship among evaluating objects, a new weight evaluation process using entropy method was introduced. This improved method for determination of weight of the evaluating indicators was applied in water quality assessment of the Three Gorges reservoir area. The results showed that this method was favorable for fuzzy synthetic evaluation when there were more than one evaluating objects. One calculation was enough for calculating every monitoring point. Compared with the original evaluation method, the method predigested the fuzzy synthetic evaluation process greatly and the evaluation results are more reasonable.

关键词： water quality evaluation fuzzy weight of evaluating indicator entropy method