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纸和造纸 2024年第3期43卷 8-11页

作者：金星明北京施澳德瑞科技有限公司北京102600

首先介绍高速纸机毛毯保洁剂的组成、分类及添加方式,随后阐述了制订高速纸机保洁方案需要考虑的问题以及使用效果的评价方法,最后阐明了高速纸机毛毯保洁剂应用的发展方向。

关键词：高速纸机毛毯保洁剂组成和分类添加方式保洁方案效果评价发展方向

Studies of Solvent Effects on Structure and Low Frequency Vibrational Spectra of 2,4-Dinitrotoluene

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Chemical Research in Chinese Universities 2009年第3期25卷 373-376页

作者： WANG Lin jin ming-xing LIU Hang DING Da-jun Institute of Atomic and Molecular Physics Jilin University Changchun 130012 P. R. China

Solvent effects on 2,4-dinitrotoluene（2,4-DNT） molecule in different solvents（toluene, ethanol, and water） were studied via DFT PCM method at B3LYP/6-311＋G（d,p） level. The influences of these solvents on the molecular structure, vibrational spectra, charge distribution, and dipole moment were studied as well. The results show that PCM computations are successful in describing the vibrational spectra of 2,4-DNT molecules in these solutions and the solvent effects on the low frequency vibrational spectra are weak.

关键词： Density functional theory Solvent effect Polarizable continuum model 2,4-Dinitrotoluene

Physical and Electrochemical Characterization of Hydrothermal Prepared α'-NaV_2O_5 Crystals

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Chemical Research in Chinese Universities 2010年第2期26卷 291-293页

作者： HU Fang WEI Ying-jin JIANG Tao ming xing CHEN Gang WANG Chun-zhong College of Physics State Key Laboratory of Superhard Materials Jilin University Changchun 130012 P. R. China

a＇-NaV2O5 was prepared by a simple hydrothermal process. X-ray diffraction confirmed the orthorhombic structure of a＇-NaV2O5, with preferential growth along the （001） direction. Scanning electron microscopy showed a＇-NaV205 was composed of flake-shaped crystals. X-ray photoelectron spectroscopy confirmed the co-existence of V^4＋ and V^5＋ in a＇-NaV2O5, which results in an average V^4.5＋ oxidation state of a＇-NaV2O5. The observed Raman bands are ascribed to different V-O vibrations, a＇-NaV205 shows a reversible specific capacity of about 100 mA·h·g^-1 between 3.5 and 1.0 V, with a good capacity retention. The good electrochemical stability of the material is attributed to its structural stability during Li^＋ intercalation.

关键词： Lithium ion battery Vanadium bronze Electrochemical performance

Ionization and Fragmentation of Butanone Clusters Irradiated by Photons at 355 and 118 nm

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Chemical Research in Chinese Universities 2011年第3期27卷 508-511页

作者： SUN Chang-kai HU Zhan YANG Xue jin ming-xing HU Wen-cheng DING Da-jun Institute of Atomic and Molecular Physics Jilin University Changchun 130012 P. R. China

Time-of-flight（TOF） mass spectra of molecular butanone clusters were measured under the irradiation of photons at 355 and 118 nm. Butanone molecular parent ion and several series of butanone cluster fragments such as （CH3COC2H5）nH＋, （CH3COC2H5）nC2H5＋, （CH3COC2H5）nCH3CO＋ and （CH3COC2H5）nC2H5CO＋ were observed. Odd-even variation pattern in the intensity of （CH3COC2H5）nCH3CO＋ is obvious from n=4 to 8. A connection is es-tablished between the fragment clusters （CH3COC2H5）nCH3CO＋ and the neutral clusters （CH3COC2H5）n＋1 based on the consideration of butanone cluster dissociation mainly by losing a radical C2H5？. The stability variation of the neutral clusters calculated via the HF-B3LYP method based on DFT is in agreement with the observed phenomena experimentally, indicating （CH3COC2H5）n＋1（n＋1=5,7） with a ring structure are with higher stability over the adjacent even-number clusters.

关键词： Cluster Ionization Fragment Butanone

Oxidation behavior of low-grade vanadiferous titanomagnetite concentrate with high titanium

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Journal of Iron and Steel Research International 2024年第2期31卷 329-341页

作者： jin-sheng Liu Zhen-xing xing Gong-jin Cheng Xue-yong Ding Xiang-xin Xue School of Metallurgy Northeastern UniversityShenyang110819LiaoningChina Liaoning Key Laboratory of Recycling Science for Metallurgical Resources Shenyang110819LiaoningChina Innovation Research Institute of Vanadium and Titanium Resource Industry Technology Northeastern UniversityShenyang110819LiaoningChina

In order to clarify the oxidation mechanisms and make better use of the low-grade vanadiferous titanomagnetite concentrate with high titanium(LVTC),the oxidation behavior of LVTC was *** results showed that oxidation degree was achieved within 90 min when temperature was not lower than 700°C,and the main phases of the oxidized LVTC consisted of Fe9TiO15,Fe2O3,CaSiTiO5 and a small amount of *** temperature is favorable to the formation of *** surface of LVTC gradually becomes rough,with fine particles of needle-like and granular shape appearing on the surface,which finally turn from laminar to creamy,spread out,and are interspersed with many tiny *** phase oxidation paths in LVTC were as follows:(1)Fe2.75Ti0.25O4→Fe9TiO15+Fe2O3;(2)Fe2.75Ti0.25O4→Fe2O3+FeTiO3→Fe2TiO5;(3)FeTiO3→Fe2O3+Fe2Ti3O9→*** is predominantly mesoporous whether oxidized or not,with the pores mainly distributed in the range of 2–40 nm,and the specific surface area of LVTC decreases significantly with increasing temperature.

关键词： Low-grade vanadiferous titanomagnetite concentrate Oxidation degree Phase transformation Micromorphology Oxidation path Pore structure

Integrating high-volume molecular and morphological data into the evolutionary studies of Allium

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Plant Diversity 2024年第1期46卷 1-2页

作者： xing-jin He Key Laboratory of Bio-Resource and Eco-Environment of Ministry of Education College of Life SciencesSichuan UniversityChengdu 610065SichuanPR China

The genus Allium(Amaryllidaceae),which includes economically important plants such as onions,garlic,and leeks,is one of the most species-rich and diverse genera of monocotyledon plants in the Northern Hemisphere(Govaerts et al.,2021),with approximately 1000 *** evolution of Allium is characterized by ecological diversification,with most species preferring open.

关键词： species evolutionary Allium

Nano polystyrene microplastics could accumulate in Nile tilapia(Oreochromis niloticus):Negatively impacts on the intestinal and liver health through water exposure

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Journal of Environmental Sciences 2024年第3期137卷 604-614页

作者： Di Wu xing Lu Li-Xue Dong Juan Tian jin Deng Lei Wei Hua Wen Shan Zhong ming Jiang School of Basic Medical Sciences Wuhan UniversityWuhan 430071China Key Laboratory of Freshwater Biodiversity Conservation Ministry of Agriculture and Rural AffairsYangtze River Fisheries Research InstituteChinese Academy of Fishery SciencesWuhan 430223China Hubei Province Key Laboratory of Allergy and Immunology Wuhan 430071China

Microplastics(MPs)have become a significant concern for their potential ***,the correlation between the size of plastic particles and their toxicity remains ***,we investigate the toxic effects of different sizes(80 nm,800 nm,8μm and 80μm)polystyrene MPs(PS-MPs)on the model organism Nile tilapia(Oreochromis niloticus).The results of bioluminescent imaging indicate that the 80 nm PS-MPs are more likely to invade the body.H&E staining shows severe damage on the intestinal villi and distinct hepatic steatosis in the 80 nm *** U labeling shows that the proliferation activity of intestinal and liver cells reduces significantly in the 80 nm *** gut microbiome analysis shows a severe imbalance of gut microbiota homeostasis in the 80 nm *** analysis of liver transcriptomics and metabolomics shows that the liver lipid metabolism is disordered in the 80 nm *** conclusion,this study confirms that the 80 nm PS-MPs are more likely to induce intestinal and liver *** the above lay the foundation for further study on the pathological damage of MPs to other organisms.

关键词： Microplastics(MPs) Intestinal toxicity Liver toxicity Gut microbiome Lipid metabolism

Even Search in a Promising Region for Constrained Multi-Objective Optimization

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IEEE/CAA Journal of Automatica Sinica 2024年第2期11卷 474-486页

作者： Fei ming Wenyin Gong Yaochu jin School of Computer Science China University of GeosciencesWuhan 430074China IEEE Faculty of Technology Bielefeld UniversityNorth Rhine-Westphalia 33619Germany School of Engineering Westlake UniversityHangzhou 310030China

In recent years, a large number of approaches to constrained multi-objective optimization problems(CMOPs) have been proposed, focusing on developing tweaked strategies and techniques for handling constraints. However, an overly finetuned strategy or technique might overfit some problem types,resulting in a lack of versatility. In this article, we propose a generic search strategy that performs an even search in a promising region. The promising region, determined by obtained feasible non-dominated solutions, possesses two general ***, the constrained Pareto front(CPF) is included in the promising region. Second, as the number of feasible solutions increases or the convergence performance(i.e., approximation to the CPF) of these solutions improves, the promising region shrinks. Then we develop a new strategy named even search,which utilizes the non-dominated solutions to accelerate convergence and escape from local optima, and the feasible solutions under a constraint relaxation condition to exploit and detect feasible regions. Finally, a diversity measure is adopted to make sure that the individuals in the population evenly cover the valuable areas in the promising region. Experimental results on 45 instances from four benchmark test suites and 14 real-world CMOPs have demonstrated that searching evenly in the promising region can achieve competitive performance and excellent versatility compared to 11 most state-of-the-art methods tailored for CMOPs.

关键词： Constrained multi-objective optimization even search evolutionary algorithms promising region real-world problems

Ultrafast Photodissociation Dynamics of the F State of Sulfur Dioxide by Femtosecond Time-Resolved Pump-Probe Method

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Chinese Physics Letters 2011年第3期28卷 58-61页

作者： ZHANG Dong-Doug NI Qiang LUO Si-Zuo ZHANG jing LIU Hang XU Hai-Feng jin ming-xing DING Da-Jun Institute of Atomic and Molecular Physics Jilin UniversityChangchun 130012

A femtosecond pump-probe method is employed to study the dissociation dynamics of sulfur ***_(2)molecules are excited to the F state by absorbing two photons of 267nm femtosecond laser pulses,and ionized by 400nm laser pulses at different delay times between the two *** of both parent ions(SO_(2)^(+))and the fragment ions(SO^(+),S^(+)and O^(+)are *** S0_(2)^(+)transient can be well fitted to a biexponential decay comprising a fast and a slow component of 280fs and 2.97ps lifetimes,*** SO^(+)transient consists of two growth components of 270 fs and 2.50 *** results clearly show that the F state of S0_(2)dissociates along an S-0 *** transients of S^(+)and O^(+),however,have different behavior,which consist of a fast growth and a long decay component.A possible mechanism of the fragment formation is discussed to understand the dissociation dynamics of the F state of SO_(2).

关键词： Femto pump dissociation

Defocusing role in femtosecond filamentation: Higher-order Kerr effect or plasma effect?

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Chinese Physics B 2015年第11期24卷 54-58页

作者：李苏宇郭福明杨玉军金明星 Institute of Atomic and Molecular Physics Jilin University Jilin Provincial Key Laboratory of Applied Atomic and Molecular Spectroscopy (Jilin University)

The femtosecond filamentation in the classical and high-order Kerr （HOK） models is numerically investigated by adopting multi-photon ionization （MPI） cross section with different values. It is found that in the case that the MPI cross section is relatively small, there exists a big difference between the electron density as well as clamped intensity calculated in the classical model and those calculated in the HOK one, while in the case that the MPI cross section is relatively large, the electron density and clamped intensity calculated in the two models are nearly in agreement with each other, and under this circumstance, even if the higher-order nonlinear terms do exist, the free-charge generation and the associated defocusing in a filament are enough to mask their effects. The different behaviors of the maximum intensity and on-axis electron density at the collapse position with the pulse duration provides an approach to determine which effect plays the dominant defocusing role. These results demonstrate that it is ionization that results in the difference between the two models.

关键词： high-order Kerr model plasma defocusing filamentation