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A structural relationship between place attachment and intention to conserve landscapes–a case study of Harz National Park in Germany

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Journal of Mountain Science 2017年第5期14卷 998-1007页

作者： Dukjae lee ju-Hyoung lee Department of Forest Resources University of Daegu Department of Forest Resources Yeungnam University

Place attachment is an important motivation for people to spend more time outdoors and to protect *** study explores visitors' intention to conserve natural landscapes based on the relationship with their place attachment to National Park landscape. Structural equation modelling(SEM) was used to determine the relationship between landscape conservation and place attachment. A survey with a structured questionnaire was administered to visitors to the seven designated hiking courses of Harz National Park in Germany. The path coefficient of 0.77 revealed that place dependence positively and significantly affected place attachment, whereas place identity did not. Place attachment had a significant effect on both affective appraisals and visiting satisfaction. Higher place attachment led to higher emotional reaction to landscapes on site and higher satisfaction of visiting the park. Among the variables, visiting satisfaction, but not affective appraisals, played a statistically significant mediating role between place attachment and conservation intention. With a path coefficient of 0.86, conservation intention was highly affected by visiting satisfaction. These results suggest that the managers of National Parks should focus on increasing visiting satisfaction based on how visitors are emotionally bonded with their visiting places, in order to enhance the intentions to conserve the landscape of the visitors to National Parks.

关键词： Place attachment Sense of place Mountain forests Structural Equation Model Landscape preference

Application of Accelerometer Data in Precise Orbit Determination of GRACE-A and-B

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Chinese Journal of Astronomy and Astrophysics 2008年第5期8卷 603-610页

作者： dong-ju Peng Bin Wu Shanghai Astronomical Observatory CAS Shanghai 200030 China Graduate University of Chinese Academy of Sciences Beijing 100049 China

We investigate how well the GRACE satellite orbits can be determined using the on- board GPS data combined with the accelerometer data. The preprocessing of the accelerometer data and the methods and models used in the orbit determination are presented. In order to assess the orbit accuracy, a number of tests are made, including external orbit comparison, and through Satellite Laser Ranging （SLR） residuals and K-band ranging （KBR） residuals. It is shown that the standard deviations of the position differences between the so-called precise science orbits （PSO） produced by GFZ, and the single-difference （SD） and zero-difference （ZD） dynamic orbits are about 7 cm and 6 cm, respectively. The independent SLR validation indicates that the overall root-mean-squared （RMS） errors of the SD solution for days 309 - 329 of 2002 are about 4.93cm and 5.22cm, for GRACE-A and B respectively; the overall RMS errors of the ZD solution are about 4.25 cm and 4.71 cm, respectively. The relative accuracy between the two GRACE satellites is validated by the KBR data to be on a level of 1.29cm for the SD, and 1.03 cm for the ZD solution.

关键词： celestial mechanics- ephemerides - methods numerical

Fabrication of perovskite solar cell with high short-circuit current density(Jsc)using moth-eye structure of SiOx

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Nano Research 2020年第4期13卷 1156-1161页

作者： Sucheol ju Minseop Byun Minjin Kim junho jun Daihong Huh dong Suk Kim Yimhyun Jo Heon lee Department of Materials Science and Engineering Korea UniversityAnam-ro 145Sungbuk-GuSeoul 136-701Republic of Korea KIER-UNIST Advanced Center for Energy Korea Institute of Energy Research(KIER)UNIST-Gil 50Eonyang-eupUlju-gunUlsan 689-851Republic of Korea

The performance of solar cells is determined by three factors:the open-circuit voltage(Voc),short-circuit current density(Jsc),and fill factor(FF).The Voc and FF are determined by the material bandgap and the series/shunt resistance,***,Jsc is determined by the amount of incident light in addition to the bandgap of the *** this study,a moth-eye pattern was formed on a glass surface via direct printing to increase the amount of incident light and thus increase Jsc-The moth-eye pattern is a typical antireflection pattern that reduces the reflection by gradually increasing the refractive index.A flat perovskite solar cell(F-PSC)and a moth-eye patterned perovskite solar cell(M-PSC)had Jsc values of 23.70 and 25.50 mA/cm^2,*** power-conversion efficiencies of the F-PSC and M-PSC were 19.81%and 21.77%,respectively.

关键词： perovskite solar cells direct printing moth-eye pattern hydrogen silsesquioxane

Femtosecond Tm-Ho co-doped fiber laser using a bulk-structured Bi2Se3 topological insulator

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Chinese Physics B 2018年第9期27卷 137-143页

作者： Jinho lee ju Han lee School of Electrical and Computer Engineering University of SeoulSeoul 02504Republic of Kore

We experimentally demonstrate a femtosecond mode-locked thulium-holmium（Tm-Ho） co-doped fiber laser incorporating a saturable absorber（SA） based on a bulk-structured bismuth selenide（Bi2Se3） topological insulator（TI）. The SA was prepared by depositing a mechanically exfoliated Bi2Se3 TI layer onto a side-polished optical fiber platform. Unlike high-quality nano-structured Bi2Se3 TI-based SA, bulk-structured Bi2Se3 with non-negligible oxidation was used as a saturable absorption material for this experimental demonstration due to its easy fabrication process. The saturation power and modulation depth of the prepared SA were measured to be -28.6 W and -13.4%, respectively. By incorporating the prepared SA into a Tm-Ho co-doped fiber ring cavity, stable soliton pulses with a temporal width of - 853 fs could be generated at 1912.12 nm. The 3-dB bandwidth of the mode-locked pulse was measured to be -4.87 nm. This experimental demonstration reaffirms that Bi2Se3 is a superb base material for mid-infrared passive mode-locking even under oxidation.

关键词： topological insulator mode-locked lasers femtosecond pulse fiber lasers

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芳香化合物磺化反应机理的计算化学研究

化学教育（中英文） 2024年第10期45卷 100-104页

作者：孙悦竹杨一莹张冬菊山东大学化学与化工学院山东济南250100

磺化反应是芳香化合物最重要的反应类型之一。最新理论研究表明,磺化反应一般遵循三分子反应机理,这与有机化学教材中描述的双分子机理有明显区别。以甲苯的磺化反应为例,通过密度泛函理论计算研究了磺化反应的分子机理、区域选择性以... 详细信息

磺化反应是芳香化合物最重要的反应类型之一。最新理论研究表明,磺化反应一般遵循三分子反应机理,这与有机化学教材中描述的双分子机理有明显区别。以甲苯的磺化反应为例,通过密度泛函理论计算研究了磺化反应的分子机理、区域选择性以及溶剂对反应性能的影响,并通过比较苯、甲苯和硝基苯磺化反应的计算结果,分析了取代基对磺化反应性能的影响。旨在通过对模型反应的计算化学研究,及时更新并深化对磺化反应机理的理解,进而提高相关教学内容的创新性、高阶性和挑战度。

关键词：芳香化合物磺化反应反应机理密度泛函理论

Synthesis and Molecular Structure of Binuclear Organotin Complex Bridged by Piperazinylbidithiocarbamate Anion

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Chinese Journal of Structural Chemistry 2004年第5期23卷 490-493页

作者： YINHan-dong WANGChuan-Hua XINGQiu-ju DepartmentofChemistry LiaochengUniversityLiaochengShandong252059China

The title complex bistri(o-fluorbenzyl)tinpiperazinylbisdithiocarbamate (C48H44- F6N2S4Sn2, Mr = 1128.47) was synthesized by the reaction of tri(o-fluorbenzyl)tin chloride with piperazinylbisdithiocarbamate in 2:1 molar ratio. The structure was characterized by elemental analysis, IR and 1H NMR, and the crystal structure was determined by X-ray single-crystal diffrac- tion. The crystal belongs to triclinic, space group P with a= 10.348(5), b = 10.636(6), c = 13.279(7) , a = 68.445(9), b = 86.763(9), g = 61.278(8)o, Z = 1, V = 1179(1) 3, Dc = 1.589 g/cm3, m = 1.296 mm-1, F(000) = 564, R = 0.0534 and wR = 0.0849. In the complex, the tin atoms are five-coordinate to a distorted tirgonal bipyramidal configuration.

关键词： tri(o-fluorbenzyl)tin piperazinylbisdithiocarbamate crystal structure

Quantitative Investigation of Tomographic Effects in Abnormal Regions of Complex Structures

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Engineering 2021年第7期7卷 1011-1022页

作者： Longjun dong Xiaojie Tong ju Ma School of Resources and Safety Engineering Central South UniversityChangsha 410083China

The detection of abnormal regions in complex structures is one of the most challenging targets for underground space *** or artificial geologic variations reduce the effectiveness of conventional exploration *** the emergence of real-time monitoring,seismic wave velocity tomography allows the detection and imaging of abnormal regions to be accurate,intuitive,and *** tomographic results are affected by multiple factors in practical small-scale applications,it is necessary to quantitatively investigate those *** adopted an improved three-dimensional(3D)tomography method combining passive acoustic emission acquisition and active ultrasonic *** varying individual parameters(i.e.,prior model,sensor configuration,ray coverage,event distributions,and event location errors),37 comparative tests were *** quantitative impact of different factors was *** experiments showed that the method could effectively adapt to complex *** optimal input parameters based on quantization results can significantly improve the detection reliability in abnormal regions.

关键词： Detection of abnormal regions Tomographic effects Wave velocity Ray path

Mechanical strength and corrosion resistance of Al-additive friction stir welded AZ31B joints

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Journal of Magnesium and Alloys 2023年第5期11卷 1519-1535页

作者： Jae-Yeon Kim Eun-Woo Kim dong-O Kim Eun-Kyo ju Ji-Eun lee Jaeheon lee Jai-Won Byeon Mining Engineering Department Colorado School of MinesGoldenCO 80401USA Department of Materials Science and Engineering Seoul National University of Science and TechnologySeoul 01811Republic of Korea

Compared to other structural alloys,magnesium alloys have a relatively poor corrosion resistance and low mechanical strength,which can be further deteriorated when these alloys are subjected to joining processes using the existing joining ***,we propose for the first time an additive friction stir-welding(AFSW)using fine Al powder as an additive to improve the mechanical strength as well as corrosion resistance of AZ31B weld *** is a solid-state welding method of forming a high-Al AZ31B joint via an in-situ reaction between pure Al powders filled in a machined groove and the AZ31B *** optimize the process parameters,AFSW was performed under different rotational and transverse speeds,and number of passes,using tools with a square or screw *** particular,to fabricate a weld zone,where the Al was homogenously dispersed,the effects of the groove shape were investigated using three types of grooves:surface one-line groove,surface-symmetric grooves,and inserted symmetric *** homogenous and defect-less AFS-welded AZ31B joint was successfully fabricated with the following optimal parameters:1400 rpm,25 mm/min,four passes,inserted symmetric grooves,and the tool with a square *** AFSW fully dissolved the additive Al intoα-Mg and in-situ precipitated Mg_(17)Al_(12)particles,which was confirmed via scanning electron microscopy,transmission electron microscope,and X-ray diffraction *** microhardness,joint efficiency,and elongation at the fracture point of the AFS-welded AZ31B joint were 80 HV,101%,and 8.9%,*** values are higher than those obtained for the FS-welded AZ31 joint in previous *** corrosion resistance of the AFS-welded AZ31B joint,evaluated via hydrogen evolution measurements and potentiodynamic polarization tests,was enhanced to 55%relative to the FS-welded AZ31B joint.

关键词： AZ31B magnesium alloy Additive friction stir-welding In-situ reaction Mg_(17)Al_(12)particles Joint efficiency Corrosion resistance

Die sinter bonding in air using copper formate preform for formation of full-density bondline

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Transactions of Nonferrous Metals Society of China 2021年第6期31卷 1717-1728页

作者： Yun-ju lee Jong-Hyun lee Department of Materials Science and Engineering Seoul National University of Science and Technology232 Gongneung-roNowon-guSeoul 139-743Korea

Pressure-assisted sinter bonding was performed in air at 250−350℃ using a preform comprising copper formate particles to form a bondline that is sustainable at high temperatures.H2 and CO generated concurrently by the pyrolysis of copper formate at 210℃ during the sinter bonding removed the native oxide and other oxides grown on bulk Cu finishes,enabling interface ***,Cu produced in situ by the reduction of Cu(II)accelerated the sinter ***,the bonding achieved at 300−350℃ under 5 MPa exhibited sufficient shear strength of 20.0−31.5 MPa after 180−300 min of sinter *** addition,an increase in pressure to 10 MPa resulted in shear strength of 21.9 MPa after an extremely short time of 30 s at 250℃,and a near-full-density bondline was achieved after 300 *** obtained results indicate the promising potential of the preform comprising copper formate particles for high-speed sinter bonding.

关键词： structural materials microstructure mechanical properties copper formate preform sinter bonding pyrolysis