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Investigating the Absorption and Desorption Behavior of Methylene Chloride in the Poly(aryl ether ketone) Film with Different Crystallinities

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Chinese Journal of Polymer Science 2024年第2期42卷 239-246,I0009页

作者： Hong-Ru yang Jin-dong Zhang dong-Ting Gao Gang Liu Chun-hai Chen Jia-Nan Yao Center for Advanced Low-Dimension Materials State Key Laboratory for Modification of Chemical Fibers and Polymer MaterialsCollege of Materials Science and EngineeringDonghua UniversityShanghai201620China

Poly(aryl ether keton e)(PAEK) films with different crystallinities were obtained by controlling the cooling rate,which were subjected to the absorption and desorption of methylene chloride(CH_(2)Cl_(2)).We employed attenuated total reflection Fourier transform infrared(ATR-FTIR)spectroscopy analyses to investigate the diffusion behavior of CH_(2)Cl_(2) in PAEK films with different *** to the Fickian diffusion model,the calculated diffu sion coefficients of CH_(2)Cl_(2) in PAEK films were observed to decrease with increasing *** effect of CH_(2)Cl_(2)absorption and desorption on the mechanical properties of PAEK films with different crystallinity was further analyzed using tensile *** tensile tests exhibited that CH_(2)Cl_(2) has two concurrent effects:plasticization and solvent-induced *** scanning calorimetry(DSC) and wide-angle X-ray diffraction(WXRD) techniques further confirmed solvent-induced crystallization *** results would be beneficial to understand the solvent resistance of PAEK materials and consequently provide the practical application conditions of PAEK with a theoretical basis.

关键词： Poly(aryl ether ketone) Diffusion behavior Infrared spectra Solvent-induced crystallization Mechanical properties

Realization of an Atomic Fountain Using a Novel Launching Method

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Chinese Physics Letters 2001年第11期18卷 1457-1459页

作者： FU Jun-Xian CHEN Shuai CHEN Xu-Zong yang dong-hai WANG Yi-Qiu Key Laboratory for Quantum Information and Measurement of Ministry of Education and Department of ElectronicsPeking UniversityBeijing 100871 Department of Physics Peking UniversityBeijing 100871

We have realized a cesium atomic fountain using a novel launching method. We have obtained 108 atoms in the magneto-optical trap experiment and have studied the temperature and launching height with different laser frequency detuning to the cesium resonance line. A fountain with a height of 1.8cm and a temperature of 30 ± 10μK was achieved. In comparison with other experiments, we have also discussed the advantages and disadvantages of our method used in the present experiment.

关键词： experiment. method. cesium

Intensity Dependence of Cesium D_(2)-Line Saturation Spectra

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Chinese Physics Letters 1996年第6期13卷 424-427页

作者： LI Yi-min CHEN Xu-zong GAN Jian-hua JI Wang-xi HUA Jing-shan yang dong-hai WANG Yi-qiu Department of Radio-Electronics Peking UniversityBeijing 100871

The intensity dependence of the cesium D_(2)-line saturation absorption spectra in a nearly zero magnetic field was investigated theoretically and *** using rate equations the D_(2)-line saturation absorption spectra were calculated,which agree reasonably well with the experimental *** variation of the spectra with different cell lengths was also reported and explained with theoretical calculation.

关键词： calculation. spectra saturation

Magneto-Optical Trap for Cesium Atoms Without a Separate Repumping Laser

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Chinese Physics Letters 1999年第11期16卷 805-807页

作者： FU Jun-xian CHEN Xu-zong LI Yi-min yang dong-hai WANG Yi-qiu Department o f Electronics Peking UniversityBeijing 100871

A magneto-optical trap (MOT) for cesium atoms that operates without a separate repumping laser is reported. The differences between a normal MOT and this kind of MOT have been experimentally studied. The influences of a repumping laser on cooling and trapping cesium atoms in the MOT have been carefully investigated. The results reveal that it is the critical injection-locked state of the diode laser that makes magneto-optical trapping of cesium atoms possible without a separate repumping laser.

关键词： pumping laser optical

Hydrogen storage thermodynamics and kinetics of as-cast Ce-Mg-Ni-based alloy

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Journal of Iron and Steel Research International 2024年第3期31卷 752-766页

作者： Yan Qi Xin Zhang Jun Li dong-liang Zhao Shi-hai Guo yang-huan Zhang Department of Functional Material Research Central Iron and Steel Research InstituteBeijing 100081China China Rare Earth New Material(Weishan)Co..Ltd. Jining 277600ShandongChina Collaborative Innovation Center of Integrated Exploitation of Bayan Obo Multi-Metal Resources Inner Mongolia University of Science and TechnologyBaotou 014010Inner MongoliaChina

The reaction kinetics of alloys based on magnesium are known to be greatly improved by the partial substitution of Mg with rare earths and transition metals,particularly *** enhanced superficial hydrogen dissociation rate,the weakened Mg-H bond and the lower activation energy following element replacement are thought to be related to the better *** experimental alloys Ce5Mg_(95-x)Ni_(x)(x=5,10,15)were smelted by the vacuum induction *** phase transformation and structural evolution of experimental alloys before and after reaction with hydrogen were char-acterized by X-ray diffraction,scanning electron microscopy and transmission electron *** cast specimens contain CeMg_(12),Mg and Mg_(2)Ni phases,and the increase in Ni content results in an obvious growth of Mg_(2)Ni *** isothermal and non-isothermal hydrogenation and dehydrogenation kinetics of the experimental specimens were investi-gated using the Sievert apparatus,differential scanning calorimetry and thermal gravimetric *** activation energy may be calculated using the Arrhenius and Kissinger *** experimental alloys have been shown to have good activation properties,with a reversible hydriding and dehydriding capacities of around 5.0 wt.%in the first *** initial dehydrogenation temperature of MgH_(2) decreases from 557.5 to 537.7 K with changing Ni content from 5 to 15 at.%.The dehydrogenation activation energy also reduces from 77.09 to 62.96 kJ/mol,which explains the improved hydrogen storage performance caused by Ni *** can be shown that the impact of Ni on the decomposition enthalpy of MgH_(2) is quite modest,with the absolute enthalpy(ΔHr)only decreasing from 78.48 to 76.15 kJ/mol.

关键词： Mg-based alloy Ni content Hydrogen storage kinetics Thermodynamic property Activation energy

Comprehensive study on the spatial distribution of heavy metals and their environmental risks in high-sulfur coal gangue dumps in China

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Journal of Environmental Sciences 2024年第2期136卷 486-497页

作者： Yingbo dong Huan Lu hai Lin School of Energy and Environmental Engineering University of Science and Technology BeijingBeijing 100083China Beijing Key Laboratory on Resource-oriented Treatment of Industrial Pollutants Beijing 100083China

The accumulation of coal gangue(CG)from coal mining is an important source of heavy metals(HMs)in *** spatial distribution and environment risk assessment are extremely important for the management and remediation of *** soil samples were collected from the high-sulfur CG site in northern China and analyzed for six *** results showed that the soil was heavily contaminated by Mn,Cr and Ni based on the Nemerow index,and posed seriously ecological risk depended on the geo-accumulation index,potential ecological risk index and risk assessment *** semi-variogram model and ordinary kriging interpolation accurately portrayed the spatial distribution of ***,Mn,and Cr were distributed by band diffusion,Ni was distributed by core,the distribution of Cu had obvious patchiness and Zn was more *** spatial autocorrelation indicated that all HMs had strong spatial *** BCR sequential extraction was employed to qualify the geochemical fractions of *** data indicated that Fe and Cr were dominated by residual fraction;Cu,Ni and Zn were dominated by reducible and oxidizable fractions;Mn was dominated by reducible and acid-extractable(25.38%-44.67%)*** correlation analysis showed that pH was the main control factor affecting the non-residue fractions of ***,acid production from high sulfur CG reduced soil pH by 2-3,which indirectly promoted the activity of ***,the conceptual model of HMs contamination at the CG site was proposed,which can be useful for the development of ecological remediation strategies.

关键词： High-sulfur coal gangue Soil contamination Heavy metals Spatial distribution Geochemical fractions Risk assessment

Bioleaching of vanadium from stone coal vanadium ore by Bacillus mucilaginosus:Influencing factors and mechanism

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International Journal of Minerals,Metallurgy and Materials 2024年第8期31卷 1828-1838页

作者： Yingbo dong Jinyu Zan hai Lin School of Energy and Environmental Engineering University of Science and Technology BeijingBeijing 100083China Beijing Key Laboratory on Resource-oriented Treatment of Industrial Pollutants Beijing 100083China

Vanadium and its derivatives are used in various industries,including steel,metallurgy,pharmaceuticals,and aerospace *** China has massive reserves of stone coal resources,these resources have low ***,the effective extraction and recovery of metallic vanadium from stone coal is an important way to realize the efficient resource utilization of stone coal vanadium ***,Bacillus mucilaginosus was selected as the leaching *** vanadium leaching rate reached 35.5%after 20 d of bioleaching under optimal operating *** cumulative vanadium leaching rate in the contact group reached 35.5%,which was higher than that in the noncontact group(9.3%).The metabolites of ***,such as oxalic,tartaric,citric,and malic acids,dominated in bioleaching,accounting for 73.8%of the vanadium leaching ***,during leaching,the presence of stone coal stimulated the expression of carbonic anhydrase in bacterial cells,and enzyme activity increased by 1.335-1.905 *** activity positively promoted the production of metabolite organic acids,and total organic acid content increased by 39.31 mg·L^(-1),resulting in a reduction of 2.51 in the pH of the leaching system with stone *** effect favored the leaching of vanadium from stone *** force microscopy illustrated that bacterial leaching exacerbated corrosion on the surface of stone coal beyond 10 *** study provides a clear and promising strategy for exploring the bioleaching mechanism from the perspective of microbial enzyme activity and metabolites.

关键词： Bacillus mucilaginosus stone coal vanadium ore bioleaching carbonic anhydrase organic acids

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求解多目标优化问题的分级变异量子进化算法

控制与决策 2009年第6期24卷 894-898,902页

作者：杨海东杨春华南理工大学自动化科学与工程学院广州510640

分析量子进化算法和免疫算子的特点,提出一种分级变异的量子进化算法,用于求解多目标优化问题.算法主要基于两个策略:首先,利用快速非受控排序和密度距离计算种群抗原-抗体的亲和度;然后,基于亲和度排序将个体进行分级,最优分级中的个... 详细信息

分析量子进化算法和免疫算子的特点,提出一种分级变异的量子进化算法,用于求解多目标优化问题.算法主要基于两个策略:首先,利用快速非受控排序和密度距离计算种群抗原-抗体的亲和度;然后,基于亲和度排序将个体进行分级,最优分级中的个体作为算法中的最优个体,大部分实施量子旋转更新和免疫操作,而剩余分级中的个体实施免疫交叉操作以获得新的个体补充种群.求解多目标0/1背包问题的实验结果表明了该算法的有效性.

关键词：量子进化算法多目标优化分级变异快速非受控排序背包问题

Energy partition in laser-induced cavitation bubbles near the rigid wall with a gas-containing hole

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Journal of Hydrodynamics 2024年第3期36卷 435-443页

作者： dong-qiao He hai-gang Wen Si-yuan Geng Chen-xi yang Qiang Zhong Zhi-feng Yao College of Water Resources and Civil Engineering China Agricultural UniversityBeijing100083China PowerChina Beijing Engineering Corporation Limited Beijing100024China State Key Laboratory of Efficient Utilization of Agricultural Water Resources Beijing100083China Beijing Engineering Research Center of Safety and Energy Saving Technology for Water Supply Network System China Agricultural UniversityBeijing100083China

To investigate the energy partition in laser-induced cavitation bubbles near the rigid wall with a gas-containing hole,we utilized a nanosecond resolution photography system based on a Q-switched Nd:YAG laser and conventional industrial camera to carefully observe the transient process of bubble collapse near the rigid wall with a gas-containing *** analyzed the generation of collapse microjets and the emission of collapse shock *** found that the cavitation bubble near the rigid wall with a gas-containing hole collapsed at different times and space,and produced various types of shock *** on the far field pressure information of the shock waves measured by hydrophone,the energy of the shock waves generated by the bubble collapse near the rigid wall with a gas-containing hole is calculated for the first *** results show that the ratio of collapse shock wave energy to bubble energy is approximately between 0.7 and 0.8.

关键词： Energy partition bubble collapse laser-induced shock wave gas-containing hole