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Particuology 2024年第9期92卷 155-165页

作者： Yan Li Heng Lin Qiaolan Yu Na Ma wei dai College of Geography and Environmental Sciences Zhejiang Normal UniversityJinhua321004China Key Laboratory of the Ministry of Education for Advanced Catalysis Materials College of Chemistry and Materials ScienceZhejiang Normal UniversityJinhua321004China

The adsorption performances of individual adsorbent such as UiO-66-NH_(2)and MgAl-layered double hydroxides(MgAl-LDH)toward levofloxacin(LVX)is less satisfactory due to the disappointing uptake capacity and adsorption ***,a 3D flower-like composite adsorbent prepared via iterative hydrothermal synthesis method anchoring UiO-66-NH_(2)nanoparticles onto the MgAl-LDH *** to the synergistic effects of UiO-66-NH_(2),and MgAl-LDH,the MgAl-LDH@UiO-66-NH_(2)exhibits an outstanding adsorption performance toward ***,the maximum LVX uptake capacity over MgAl-LDH@UiO-66-NH_(2)reached 268 mg/g,which was higher than that of the individual adsorption materials UiO-66-NH_(2)(41 mg/g),MgAl-LDH(140 mg/g),and some adsorbents reported in previous *** rapid adsorption process can reach equilibrium within 20 min,which conformed well to the pseudo-second-order kinetics and the Langmuir isotherm *** thermodynamic result also indicated that the adsorption was spontaneous and exothermic,simultaneous coexisting physical and chemical adsorption ***,the MgAl-LDH@UiO-66-NH_(2)still maintained excellent adsorption capacity with a slightly decrease after fifth cycle,exhibiting a remarkable reuse and stable *** work provides a highly novel strategy to prepare recyclable composite adsorbent for the LVX capture from aqueous solution.

关键词： Layered double hydroxides UiO-66-NH_(2) LVX Adsorption

The Differentiated Effect of Administrative Policy in China’s Housing Market——Based on the Heterogeneous Households Multi-Agent Model

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Journal of Systems Science & Complexity 2020年第1期33卷 167-195页

作者： LIU Jiajia dai wei LI Xiuting DONG Zhi DONG Jichang School of Economics and Management Beijing University of Chemical TechnologyBeijing 100029China School of Economics and Management University of Chinese Academy of SciencesBeijing 100190China

Since 2010,Chinese government has introduced a series of administrative policies to limit speculation in the housing market to stabilize price fluctuations and keep the housing market in a healthy state of *** order to investigate whether administrative policy can play its due role,this paper constructs a comprehensive bottom-up housing market heterogeneous households multiagent model(HHMAM)to undertake research on the differentiated effect of administrative policy in different *** empirical studies find that:1)Administrative policy that increases interest rates will cause housing prices to continue to decline in the long term,but they will resume a rising trend after reaching the lowest point;2)If the government cancels a property-purchasing limitation,housing prices will continue to rise;and 3)investors tend to invest in 1st-tier cities due to the high demand and greater likelihood of appreciation in these cities.

关键词： Administrative policy consumer behavior heterogeneous households multi-agent model housing prices regional differentiation

不同气压环境下水工混凝土含气量发展规律研究

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硅酸盐通报 2025年第1期44卷 112-123页

作者：代薇杨淘孙彦梅张芮瑜秦小枫蔡君怡李阳中国长江电力股份有限公司宜宾644612 西安理工大学水利水电学院西安710032

我国西南及西北部分地区具有较大的地势高差,气压相对较低,水工混凝土常常暴露在低气压环境下,导致其耐久性降低。本文研究了不同气压环境对水工混凝土含气量和引气剂溶液性能的影响。结果表明,低气压使引气剂溶液的引气能力明显减弱,... 详细信息

我国西南及西北部分地区具有较大的地势高差,气压相对较低,水工混凝土常常暴露在低气压环境下,导致其耐久性降低。本文研究了不同气压环境对水工混凝土含气量和引气剂溶液性能的影响。结果表明,低气压使引气剂溶液的引气能力明显减弱,气泡衰亡速率提高。极差和方差分析表明:在101和80 kPa环境中,各因素对含气量的影响程度由大到小排序为引气剂掺量、水胶比、粉煤灰掺量;而在50 kPa环境下,各因素对含气量的影响程度由大到小排序为水胶比、引气剂掺量、粉煤灰掺量。随着气压的降低,硬化混凝土含气量减小,低气压环境下的气泡更容易汇聚形成大气泡,水工混凝土硬化后气孔结构逐渐劣化,具体表现为试样孔隙结构劣化严重。同时,硬化混凝土的平均孔径和平均气孔间距系数增大,硬化混凝土含气量明显小于新拌混凝土含气量。低气压环境延缓了水泥水化过程,导致基体中气泡的稳定性降低,进而造成硬化混凝土含气量减少。

关键词：水工混凝土气压环境引气剂引气能力孔隙结构含气量配合比参数

Behavior recognition algorithm based on the improved R3D and LSTM network fusion

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High Technology Letters 2021年第4期27卷 381-387页

作者： Wu Jin An Yiyuan dai wei Zhao Bo School of Electronic and Engineering Xi’an University of Posts and TelecommunicationsXi’an 710121P.R.China

Because behavior recognition is based on video frame sequences,this paper proposes a behavior recognition algorithm that combines 3D residual convolutional neural network(R3D)and long short-term memory(LSTM).First,the residual module is extended to three dimensions,which can extract features in the time and space domain at the same ***,by changing the size of the pooling layer window the integrity of the time domain features is preserved,at the same time,in order to overcome the difficulty of network training and over-fitting problems,the batch normalization(BN)layer and the dropout layer are *** that,because the global average pooling layer(GAP)is affected by the size of the feature map,the network cannot be further deepened,so the convolution layer and maxpool layer are added to the R3D ***,because LSTM has the ability to memorize information and can extract more abstract timing features,the LSTM network is introduced into the R3D *** results show that the R3D+LSTM network achieves 91%recognition rate on the UCF-101 dataset.

关键词： behavior recognition three-dimensional residual convolutional neural network(R3D) long short-term memory(LSTM) dropout batch normalization(BN)

Effect of Al_(2)O_(3)/SiO_(2) ratio on morphology of complex calcium ferrite

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Journal of Iron and Steel Research International 2023年第10期30卷 1921-1928页

作者： dai-wei Yang wei Wang Jing-xuan Li Xu-heng Chen Peng-fei Chen Jiangsu Yonggang Group Co. Ltd.IronworksSuzhou 215600JiangsuChina Hubei Provincial Engineering Technology Research Center of Metallurgical Secondary Resources Wuhan University of Science and TechnologyWuhan 430081HubeiChina Beijing Zhiye Interconnection Technology Co. Ltd.Beijing 100144China

Al_(2)O_(3) and SiO_(2) greatly influence the formation of complex calcium ferrite,which is the main bonding phase in high basicity *** effects of Al_(2)O_(3)/SiO_(2) ratios on the morphology of complex calcium ferrite were *** main mineral phases in the samples with different Al_(2)O_(3)/SiO_(2) ratios were CaFe_(2)O_(4) with a solid solution of Si or Al atoms and the silico-ferrite of calcium and *** results showed that the morphology of the complex calcium ferrite changed from lumpy to plate-like and acicular with increases in the SiO_(2) content and the Al_(2)O_(3)/SiO_(2) *** the content of SiO_(2) was 4 wt.%,the main calcium ferrite morphology was acicular,and the number of macropores in the samples increased with the Al_(2)O_(3)/SiO_(2) ratio *** first-principles analysis of the calcium ferrite crystal structure showed that adding SiO_(2) and Al_(2)O_(3) changed the growth mechanism of the CaFe_(2)O_(4) crystal,promoting the formation of platy and acicular complex calcium *** size of calcium ferrite was significantly smaller due to the increase in CaO-Fe_(2)O_(3)-SiO_(2)-Al_(2)O_(3) viscosity with increasing the Al_(2)O_(3)/SiO_(2) ratio.

关键词： Complex calcium ferrite Silico-ferrite of calcium and aluminum Al_(2)O_(3)/SiO_(2)ratio Morphology First-principles calculation

Probing cold nuclear matter effects with th e productions of isolated-γ and γ+jet in p+Pb collisions at (sNN)^(1/2)= 8.16 TeV

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Chinese Physics C 2019年第4期43卷 106-113页

作者： Guo-Yang Ma wei dai Ben-wei Zhang Key Laboratory of Quark & Lepton Physics (MOE) and Institute of Particle Physics Central China Normal University School of Mathematics and Physics China University of Geosciences

We investigate cold nuclear matter(CNM) effects on the productions of isolated prompt photons and +jet in proton-lead collisions at 8.16 TeV under next-to-leading order perturbative quantum chromodynamics calculations with four parameterizations for nuclear parton distribution functions(nPDFs), i.e., DSSZ, EPPS16, nCTEQ15, and nIMParton. Our theoretical calculations provide good descriptions of the pp baseline in the ATLAS collaboration and make predictions for future experimental results at p+Pb collisions. We calculate the dependence of the nuclear modification factor of isolated prompt photons on transverse momentum pу/T and pseudo-rapidity η~у at very forward and backward rapidity regions, and we demonstrate that the forward-to-backward yield asymmetries Yasym/pPb as a function of pу/T with different nPDF parameterizations have diverse behaviors. Furthermore, the nuclear modification factor of isolated-у+jet RуJet/pPb as a function of у+jet's pseudo-rapidity η_(уJet)=1/2(η_у+η_(Jet)) at different average transverse momenta pavg/T=1/2(pу/T+pJet/T) has been discussed. This can facilitate a tomographic study of CNM effects with precis locations in a rather wide kinematic region by varying the transverse momenta and rapidities of both isolated photons and jets in p+A collisions.

关键词： relativistic heavy-ion collisions cold nuclear matter effects perturbative QCD prompt photon production

Soil carbon budget in different-aged Chinese fir plantations in south China

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Journal of Forestry Research 2014年第3期25卷 621-626页

作者： Shebao Yu Dan Wang wei dai Ping Li College of Forestry Beijing Forestry University Jiangxi Agricultural University Key Laboratory of Forest Ecological Environment Research Institute of Forest Ecology Environment and Protection Chinese Academy of Forestry State Forestry Administration Beijing Soil and Fertilizer Extension Service Station

Understanding the age effect on soil carbon balance in forest ecosystems is important for other material cycles and forest man-agement. In this research we investigated soil organic carbon density, litter production, litter decomposition rate, soil respiration, and soil mi-crobial properties in a chronosequence of four Chinese fir plantations of 7, 16, 23 and 29 years at Dagangshan mountain range, Jiangxi Province, south China. There was a significant increasing trend in litter production with increasing plantation age. Litter decomposition rate and soil respira-tion, however, declined from the 7-year to the 16-year plantation, and then increased after 16 years. This was largely dependent on soil micro-organisms. Soil carbon output was higher than carbon input before 16 years, and total soil carbon stock declined from 35.98 t＆#183;ha-1 in the 7-year plantation to 30.12 t＆#183;ha-1 in the 16-year plantation. Greater litter produc-tion could not explain the greater soil carbon stock, suggesting that forest growth impacted this microbial process that controlled rates of soil car-bon balance together with litter and soil respiration. The results highlight＆amp;nbsp;the importance of the development stage in assessing soil carbon budget and its significance to future management of Chinese fir plantations.

关键词： Chinese fir soil microbial properties litter production litter decomposition rate soil respiration soil carbon stock

Online complex nonlinear industrial process operating optimality assessment using modified robust total kernel partial M-regression

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Chinese Journal of Chemical Engineering 2018年第4期26卷 775-785页

作者： Fei Chu wei dai Jian Shen Xiaoping Ma Fuli Wang School of Information and Control Engineering China University of Mining and Technology Xuzhou 221116 China State Key Laboratory of Integrated Automation for Process Industries Northeastern University Shenyang 110819 China College of Information Science and Engineering Northeastern University Shenyang 110819 China

Although industrial processes often perform perfectly under design conditions, they may deviate from the optimal operating point owing to parameters drift, environmental disturbances, etc. Thus, it is necessary to develop efficacious strategies or procedure to assess the process performance online. In this paper, we explore the issue of operating optimality assessment for complex industrial processes based on performance-similarity considering nonlinearities and outliers simultaneously, and a general enforced online performance assessment framework is proposed. In the offline part, a new and modified total robust kernel projection to latent structures algorithm,T-KPRM, is proposed and used to evaluate the complex nonlinear industrial process, which can effectively extract the optimal-index-related process variation information from process data and establish assessment models for each performance grades overcoming the effects of outlier. In the online part, the online assessment results can be obtained by calculating the similarity between the online data from a sliding window and each of the performance grades. Furthermore, in order to improve the accuracy of online assessment, we propose an online assessment strategy taking account of the effects of noise and process uncertainties. The Euclidean distance between the sliding data window and the optimal evaluation level is employed to measure the contribution rates of variables, which indicate the possible reason for the non-optimal operating performance. The proposed framework is tested on a real industrial case: dense medium coal preparation process, and the results shows the efficiency of the proposed method comparing to the existing method.

关键词： Performance assessment Optimization Model Economics T-KPRM Robust

Saturation phenomenon of Ce and Ti in the modification of Al–Zn–Si filler metal

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International Journal of Minerals,Metallurgy and Materials 2015年第2期22卷 184-189页

作者： Jin-long Yang Song-bai Xue wei dai Peng Xue College of Materials Science and Technology Nanjing University of Aeronautics and Astronautics Zhejiang Xinrui Welding Material Co. Ltd.

Cerium and titanium were added to an A1-42Zn-5.5Si brazing alloy, and the subsequent microstructures of the brazing alloy and the 6061 AI alloy brazing seam were investigated. The microstructures of filler metals and brazed joints were characterized by scanning elec- tron microscopy and X-ray energy dispersion spectrometry. A new Ce-Ti phase formed around the silicon phase in the modified filler metal and this saturation phenomenon was analyzed. Interestingly, following brazing of the 6061 alloy, there is no evidence of the Ce--Ti phase in the brazing seam. Because of the mutual solubility of the brazing alloy and base metal, the quantity of the solvent increases, and the solute Ce and Ti atoms assume an undersaturated state.

关键词： filler metals aluminum alloys brazing cerium titanium saturation

Reverse Microemulsion Synthesis and Characterization of Pd-Ag Bimetallic Alloy Catalysts Supported on Al_2O_3 for Acetylene Hydrogenation

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China Petroleum Processing & Petrochemical Technology 2012年第3期14卷 59-67页

作者： wei Guobin dai wei Li Qian Cao weiliang Zhang Jingchang Institute of Modern Catalysis Beijing University of Chemical TechnologyState Key Laboratory of Chemical Resource Engineering Ethylene Technique Department Beijing Research Institute of Chemical IndustrySINOPEC

Pd-Ag bimetallic alloy nanoparticles were synthesized by the reverse microemulsion method, and then deposited on A1203 to form the supported catalyst. The nanoparticles of Pd-Ag and Pd-Ag/AI203 samples were characterized by UV/ Vis, HRTEM, EDX, XRD, and XPS. The test results indicated that Pd-Ag bimetallic alloy nanoparticles with a size of about 2 nm and a face-centered cubic （fcc） structure were formed in the measured area of microemulsion. The growth of nanopar- ticles was effectively limited within the droplet of micoremulsion. TEM image exhibited that the Pd-Ag alloy nanoparticles were well-dispersed on the A1203 support. The catalytic performance of various catalysts for selective hydrogenation of acetylene showed that a higher acetylene conversion and selectivity to ethylene upon acetylene hydrogenation was achieved on a nano-sized Pd-Ag bimetallic catalyst with a Pd/Ag alloy supported molar ratio of 1：1.5.

关键词： reverse microemulsion Pd-Ag bimetallic catalyst nanoparticle acetylene hydrogenation