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Anneal and concentration effect on PL Properties of Sol-Gel Derived Eu^(3+) Doped SiO_2 Glass

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Journal of Rare Earths 2006年第z2期24卷 199-203页

作者：王忆凌浪生朱慧群丁瑞钦 Institute of Thin Film and Nano Materials Wuyi University Structure Research Laboratory University of Science and Technology of ChinaHefei 230026China Structure Research Laboratory University of Science and Technology of China

Eu3+ doped SiO2 nano-crystalline glasses were prepared by sol-gel method. The broad peak of XRD pattern indicates an amorphous SiO2 matrix. The affection of anneal time and anneal temperatures on photoluminescence (PL) properties of SiO2 glass under different Eu doping concentration were studied systematically. It is found that the optimized anneal time is about 3 h. The excitation spectra of 2% Eu3+ doped SiO2 glass powder were measured under various anneal temperatures, and the optimized anneal temperature is observed around 700℃. The fluorescence-quenching effect can be observed in the emission spectra when the annealing temperature exceeds 700℃. The emission spectra of different molar ratio dopants were measured at an annealed temperature of 500℃, and the concentration-quenching phenomenon has also been observed in SiO2 glass powder when the molar ratio of Eu3+ ion exceeds 3% . The result shows that the PL intensity approaches its maximum when the molar ratio of Eu3+ ions in the sample is about 3% . In addition, a comparatively stronger emission spectrum at wavelength of 703 nm which is corresponding to the energy transition 5D0→7F4 of Eu ions is also obtained.

关键词： SiO2 matrix anneal temperature concentration effect fluorescence-quenching effect rare earths

effect of Phosphatization on Element concentration of Cobalt-Rich Ferromanganese Crusts

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Acta Geologica Sinica(English Edition) 2005年第3期79卷 349-355页

作者： PANJiahuax E.H.DeCARLO YANGYi LIUShuqin YOUGuoqin InstituteofMineralResources ChineseAcademyofGeologicalSciencesBeijing100037China DepartmentofOceanography UniversityofHawaii21000PopeRd.HonoluluHawaii96822U.S.A. TheGraduateSchoolofTheChineseAcademyofSciences YuquanRoad18Beijing100049China

A detailed study on a small scale of the effect of phosphatization on the chemistry of marine cobalt-rich ferromanganese crusts supplies useful information for the evaluation and comprehensive utilization of crust mineral resources. Sub-samples from top to bottom of a 10-cm thick sample from the NW Pacific Magellan seamount were taken at 5 mm intervals. The concentration profiles of ore-forming and rare earth elements show that obvious differences exist between young unphosphatized crusts and old phosphatized crusts. In the old crusts Fe, Mn, Si, Al, Zn, Mg, Co, Ni and Cu elements are depleted and Ca, P, Sr, Ba and Pb elements are enriched. The order of depletion is Co > Ni > Mg > Al > Mn > Si> Cu > Zn > Fe, while the order of enrichment is P > Ca > Ba > Pb > Sr. The phosphate mineral controls the concentration variation of the ore-forming elements in crusts and causes loss of the main ore-forming elements such as Co and Ni. The phosphatization also affects the abundance of REEs in the crusts. REEs are more abundant and the content of Ce in old crusts is higher than that in young crusts, however, the pattern of REEs and their fractionation characteristics in new and old crusts are not fundamentally changed. A Y-positive anomaly in old crusts has no relationship to the phosphatization.

关键词： phosphatization ore-forming element REE Co-rich crust concentration effect Pacific

effects of concentration, distance, and application methods of Altriset （Chlorantraniliprole） on eastern subterranean termite （Isoptera： Rhinotermitidae）

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Insect Science 2015年第3期22卷 451-460页

作者： Znar Barwary Austin Gorzlancyk Xing Ping Hu Department of Entomology and Plant Pathology Auburn University Auburn AL 36849-5413 USA

The effects of various concentrations, distance, and application methods of Altriset （Chlorantraniliprole） were investigated against one of the most destructive termites, the eastem subterranean termite, Reticulitermesflavipes Kollar. Three laboratory experiments were conducted. First, we examined the concentration effect of treating the soil contiguously to established foraging tunnels at a fixed 1 m distance. The results demonstrated 100% termite control in 19 d posttreatment at 100 and 50μg/g and 27% termite mortality at 25μg/g. Second, we tested the distance effect of the soil treatment （2 and 4 m） on the efficacy of Altriset to the satellite termite populations at a fixed 50/zg/g concentration. This resulted in 100% termite control in 22 d posttreatment at both 2 and 4 m. Third, we examined the effect of differing application methods using 12.5 and 25μg/g prior to the establishment of foraging tunnels at a fixed 1 m distance. This illustrated 100% termite control in 9 d posttreatment at 25μg/g and 12 d posttreatment at 12.5μg/g. The third experiment demonstrated soil treatments that were applied prior to termite tunnel establishment had greater efficacy than applications made post tunnel construction. Our results provide a comprehensive understanding about the efficacy of Altriset treatments on eastern subterranean termites.

关键词： application methods Chlorantraniliprole concentration effect distance effect Reticulitermesflavipes soil treatment

concentration　dependent　fluorescent　characteristics　of　Ti3＋　ion　doped　sapphire　crystal

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Chinese Journal of Lasers 1994年第5期B3卷 475-480页

作者： LIU Jianhua DENG Peizhen GAN Fuxi(Shanghai Institute of Optics and Fine Mechanics,Academia Sinica,P.0.Box 800-216,Shanghai 201800, China) Shanghai Inst of Optics and Fine Mechanics Academia Sinica Shanghai China

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关键词： Al2O3 crystal concentration effect

Thermal and concentration analysis of Phan-Thien-Tanner fluid flow due to ciliary movement in a peripheral layer

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Journal of Central South University 2021年第11期28卷 3327-3339页

作者： Khadija MAQBOOL Sidra SHAHEEN Elena BOBESCU R.ELLAHI Department of Mathematics and Statistics International Islamic UniversityIslamabadPakistan Department of Medical and Surgical Specialties Faculty of MedicineTransilvania University of BrasovBrasovRomania Fulbright Fellow Department of Mechanical Engineering University of California RiversideUSA

This paper presents the analysis of two-layer cilia induced flow of Phan-Thien-Tanner(PTT) fluid with thermal and concentration *** Phan-Thien-Tanner fluid model has been used in the analogy of mucus present in the respiratory *** two-layer model approach was used due to the Peri Ciliary liquid Layer(PCL) and Airway Ciliary Layer(ACL) present on the epithelium cell in respiratory *** mathematical modelling of two-layer flow problem was simplified using long wavelength and small Reynold ’ s number *** resulting differential equation with moving boundary gives exact solution for velocity,temperature and concentration profiles in two *** change in pressure has calculated by the results of velocity profile,also the pressure rise was evaluated by the numerical integration of pressure gradient along the channel *** impact of physical parameters on pressure rise,velocity,temperature and concentration profile was explained by the *** can be seen from graphs that velocity and temperature profile are maximum in the inner layer of fluid(PCL) and concentration profile is maximum at outer layers of fluid(ACL).

关键词： ciliary flow PTT fluid two-layer model thermal analysis concentration effect

Bottom-up construction of mesoporous supramolecular isomers based on a Pd_(3)L_(6) triangular prism as templates for shape specific aggregation of polyiodide

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Nano Research 2022年第3期15卷 2655-2660页

作者： Wen-Jie Shi Xin Li Peng Li Ying-Feng Han Key Laboratory of Synthetic and Natural Functional Molecule of the Ministry of Education College of Chemistry and Materials ScienceNorthwest UniversityXi’an 710127China Shanghai Key Laboratory of Molecular Catalysis and Innovative Materials Department of ChemistryFudan UniversityShanghai 200438China

Bottom-up construction of highly complex architecture from simple components remains one of the long-standing challenges in *** two supramolecular isomers based on large trigonal prismatic Pd_(3)L^(1)_(6)building block are ***,they can be controllably obtained by adjusting the solute concentration during crystal ***,the square shape crystals,α-[Pd_(3)L^(1)_(6)](PF_(6))_(12)in the cubic system with I143 m space group,can be isolated from a high-concentration solution of Pd_(3)L^(1)_(6).Interestingly,a mesoporous cage assembled from eight Pd_(3)L^(1)_(6)units with a diameter of 24Åis observed in the crystal *** the low-concentration solution of Pd_(3)L^(1)_(6),the rectangular shape crystalsβ-[Pd_(3)L^(1)_(6)](PF_(6))_(12)are obtained,which crystallize in the hexagonal system with P 63/m space group,and display two-dimension packing pattern and one-dimension mesoporous channels(diameter ca.22Å)along the c ***,the two supramolecular isomers were used as nanoporous reactors to induce the specific formation of polyiodides with different compositions and shapes as evidenced from single crystal X-ray diffraction *** findings provide a reference in targeting functional crystalline mesoporous supramolecular materials from a single complex building unit.

关键词： supramolecular isomers crystal growth self-assembly polyiodide concentration effect mesoporous supramolecular material

Deployment of wind turbine in between cement silos for small power generation

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Journal of Control and Decision 2023年第2期10卷 160-173页

作者： Akhilesh A.Nimje Priya Tandel Aakesh Patel Department of Electrical Engineering Institute of TechnologyNirma UniversityS.G.HighwayAhmedabadIndia JK Lakshmi Cement Ltd SuratIndia

This study provides an overview of Building-Integrated Wind Turbines,focusing on cement silos as wind concentrators,along with determining the amount of power that could be connected without regard to wind *** motivation of this research is the intermittency issue of wind stream in an open environment and non-exploration of wind turbines between cement ***-Augmented Wind Turbines provide 717 W of aerodynamic power at 16 m/s,whereas Standalone Wind Turbines produce 562 *** is due to the wind speed acceleration between buildings,which causes a concentration ***,using the simulation software ANSYS,the turbine geometry is developed utilising a Computational Fluid Dynamics evaluation.

关键词： Utilisation of wind energy concentration effect building augmented wind turbine computational fluid dynamics power augmentation factor

Simulation of Near-Fault Strong Ground Motion in the Beijing Region

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Earthquake Research in China 2007年第3期21卷 281-292页

作者： Pan Bo Xu Jiandong Haruko Sekigguchi He Honglin Institute of Geology China Earthquake Administration Beijing 100029 China Active Fault Research Center Tsukuba Ibaraki 305-8567 Japan

On the basis of previous study of the 1679 Sanhe-Pinggu(M8.0) earthquake,the biggest event in history ever recorded in Beijing and its adjacent area,we made a 3-D strong ground motion simulation utilizing the staggered-grid finite differences method to study the distributions of peak ground velocity with different earthquake source models in the Beijing *** the paper,earthquake source models and a transmission medium velocity model are established and the corresponding parameters are given in accordance to the results from a related previous ***,using a three-dimensional finite difference computing program of near-fault strong ground motion developed by Graves,the peak ground velocity caused by a destructive earthquake in the Beijing area is *** our computation model,the earthquake source is 3km in depth,and a total number of 21,679 observation points on the ground surface are figured *** transmission medium velocity model is composed of four stratums which are the Quaternary deposit,the upper crust,the upper part of the middle crust and the lower part of the middle *** the minimum grid spacing of 0.15km,a total of 2.28×106 grids are *** a time step of 0.02 seconds we calculated the peak ground velocity for a duration of 8 *** the analysis of the simulation results,we observed some basic characteristics of near-fault strong ground motion such as the concentration effect of near-fault peak ground velocity,rupture directivity effect,hanging wall effect,and basin *** results from our simulation and analysis suggest that the source and transmitting medium parameters in our model are suitable and the finite difference method is applicable to estimate the distribution of strong ground motion in the study region.

关键词： Strong ground motion Source parameter Transmitting medium parameter concentration effect Rupture directivity effect Hanging wall effect, basin effect