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Impact of wetting-drying cycles and acidic conditions on the soil aggregate stability of yellow‒brown soil

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Journal of Mountain Science 2024年第6期21卷 2075-2090页

作者： XIA Zhenyao NI Yuanzhen LIU Deyu WANG Di XIAO Hai Key Laboratory of Geological Hazards on three gorges Reservoir Area Ministry of EducationYichang 443002China College of Civil Engineering&Architecture China Three Gorges UniversityYichang 443002China Engineering Research Center of Eco-environment in three gorges Reservoir Region Ministry of EducationChina Three Gorges UniversityYichang 443002China

Soil aggregate is the basic structural unit of soil,which is the foundation for supporting ecosystem functions,while its composition and stability is significantly affected by the external *** study was conducted to explore the effect of external environment(wetting-drying cycles and acidic conditions)on the soil aggregate distribution and stability and identify the key soil physicochemical factors that affect the soil aggregate *** yellow‒brown soil from the three gorges Reservoir area(TGRA)was used,and 8 wetting-drying conditions(0,1,2.3,4,5,10 and 15 cycles)were simulated under 4 acidic conditions(pH=3,4,5 and 7).The particle size distribution and soil aggregate stability were determined by wet sieving method,the contribution of environmental factors(acid condition,wetting-drying cycle and their combined action)to the soil aggregate stability was clarified and the key soil physicochemical factors that affect the soil aggregate stability under wetting-drying cycles and acidic conditions were determined by using the Pearson’s correlation analysis,Partial least squares path modeling(PLS‒PM)and multiple linear regression *** results indicate that wetting-drying cycles and acidic conditions have significant effects on the stability of soil aggregates,the soil aggregate stability gradually decreases with increasing number of wetting-drying cycles and it obviously decreases with the increase of ***,the combination of wetting-drying cycles and acidic conditions aggravate the reduction in the soil aggregate *** wetting-drying cycles,acidic conditions and their combined effect imposes significant impact on the soil aggregate stability,and the wetting-drying cycles exert the greatest *** soil aggregate stability is significantly correlated with the pH,Ca^(2.),Mg^(2.),maximum disintegration index(MDI)and soil bulk density(SBD).The PLS‒PM and multiple linear regression analysis further reveal that the soil aggre

关键词： Yellow‒brown soil Wetting-drying cycles Acidic conditions Soil aggregate stability Soil disintegration

SHARP MORREY REGULARITY THEORY FOR A FOURTH ORDER GEOMETRICAL EQUATION

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Acta Mathematica Scientia 2024年第2期44卷 420-430页

作者：向长林郑高峰 three gorges Mathematical Research Center China Three Gorges UniversityYichang443002China School of Mathematics and Statistics Central China Normal UniversityWuhan430079China

This paper is a continuation of recent work by Guo-Xiang-Zheng[10].We deduce the sharp Morrey regularity theory for weak solutions to the fourth order nonhomogeneous Lamm-Rivière equation △^{2.u=△(V▽u)+div(w▽u)+(▽ω+F)·▽u+f in B^(4),under the smallest regularity assumptions of V,ω,ω,F,where f belongs to some Morrey *** work was motivated by many geometrical problems such as the flow of biharmonic *** results deepens the Lp type regularity theory of[10],and generalizes the work of Du,Kang and Wang[4]on a second order problem to our fourth order problems.

关键词： fourth order elliptic equation regularity theory Morrey space decay estimates Riesz potential

Preparation and Reinforcement Adaptability of Jute Fiber Reinforced Magnesium Phosphate Cement Based Composite Materials

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Journal of Wuhan university of Technology(Materials Science) 2024年第4期39卷 999-1009页

作者：刘芯州郭远臣 WANG Rui XIANG Kai WANG Xue YE Qing College of Civil Engineering Chongqing Three Gorges UniversityChongqing 404100China

To improve the brittleness characteristics of magnesium phosphate cement-based materials(MPC)and to promote its promotion and application in the field of structural reinforcement and repair,this study aimed to increase the toughness of MPC by adding jute fiber,explore the effects of different amounts of jute fiber on the working and mechanical properties of MPC,and prepare jute fiber reinforced magnesium phosphate cement-based materials(JFRMPC)to reinforce damaged *** improvement effect of beam performance before and after reinforcement was compared,and the strengthening and toughening mechanisms of jute fiber on MPC were explored through microscopic *** experimental results show that,as the content of jute fiber(JF)increases,the fluidity and setting time of MPC decrease continuously;When the content of jute fiber is 0.8%,the compressive strength,flexural strength,and bonding strength of MPC at 2. days reach their maximum values,which are increased by 18.0%,2..5%,and 2..6%compared to those of M0,*** beam strengthened with JFRMPC can withstand greater deformation,with a deflection of 2.3 times that of the unreinforced beam at *** strain of the steel bar is greatly reduced,and the initial crack and failure loads of the reinforced beam are increased by 192.1%and 16.1%,respectively,compared to those of the unreinforced *** JF added to the MPC matrix dissipates energy through tensile fracture and debonding pull-out,slowing down stress concentration and inhibiting the free development of cracks in the matrix,enabling JFRMPC to exhibit higher strength and better *** JF does not cause the hydration of MPC to generate new compounds but reduces the amount of hydration products generated.

关键词： magnesium phosphate cement jute fiber reinforcement of damaged beam flexural behavior

Response Mechanisms to Flooding Stress in Mulberry Revealed by Multi-Omics Analysis

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Phyton-International Journal of Experimental Botany 2024年第2期93卷 227-245页

作者： Jingtao Hu Wenjing Chen Yanyan Duan Yingjing Ru Wenqing Cao Pingwei Xiang Chengzhi Huang Li Zhang Jingsheng Chen Liping Gan College of Biology and Food Engineering Chongqing Three Gorges UniversityChongqing404100China Chongqing three gorges Academy of Agricultural Sciences Chongqing Three Gorges UniversityChongqing404155China

Abiotic stress,including flooding,seriously affects the normal growth and development of ***(Morus alba),a species known for its flood resistance,is cultivated worldwide for economic *** transcriptomic analysis has identified numerous differentially expressed genes(DEGs)involved in submergence tolerance in mulberry ***,a comprehensive analyses of metabolite types and changes under flooding stress in mulberry remain unreported.A non-targeted metabolomic analysis utilizing liquid chromatographytandem mass spectrometry(LC-MS/MS)was conducted to further investigate the effects of flooding stress on mulberry.A total of 1,169 metabolites were identified,with 331 differentially accumulated metabolites(DAMs)exhibiting up-regulation in response to flooding stress and 314 displaying *** enrichment analysis identified significant modifications in many metabolic pathways due to flooding stress,including amino acid biosynthesis and metabolism and flavonoid *** and DEGs are significantly enriched in the Kyoto Encyclopedia of Genes and Genomes(KEGG)pathways for amino acid,phenylpropanoid and flavonoid ***,metabolites such as methyl jasmonate,sucrose,and D-mannose 6-phosphate accumulated in mulberry leaves post-flooding ***,genes and metabolites associated with these KEGG pathways are likely to exert a significant influence on mulberry flood *** study makes a substantial contribution to the comprehension of the underlying mechanisms implicated in the adaptation of mulberry plants to submergence.

关键词： Mulberry flooding stress flavonoid biosynthesis phenylpropanoid biosynthesis

THE INTERIOR TRANSMISSION EIGENVALUE PROBLEM FOR AN ANISOTROPIC MEDIUM BY A PARTIALLY COATED BOUNDARY

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Acta Mathematica Scientia 2024年第1期44卷 339-354页

作者：向建立严国政 three gorges Mathematical Research Center College of ScienceChina Three Gorges UniversityYichang443002China School of Mathematics and Statistics Central China Normal UniversityWuhan430079China

We consider the interior transmission eigenvalue problem corresponding to the scattering for an anisotropic medium of the scalar Helmholtz equation in the case where the boundary?Ωis split into two disjoint parts and possesses different transmission *** the variational method,we obtain the well posedness of the interior transmission problem,which plays an important role in the proof of the discreteness of *** we achieve the existence of an infinite discrete set of transmission eigenvalues provided that n≡1,where a fourth order differential operator is *** the case of n■1,we show the discreteness of the transmission eigenvalues under restrictive assumptions by the analytic Fredholm theory and the T-coercive method.

关键词： interior transmission eigenvalue anisotropic medium partially coated boundary the analytic Fredholm theory T-coercive method

Adsorption of trichlorphon on phyllosilicate minerals:Effect of low-molecular-weight organic acids

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Pedosphere 2024年第1期34卷 78-87页

作者： Hongfeng CHEN Zhouyang HE Mingxia HOU Cilai TANG Yonghong WU College of Hydraulic&Environmental Engineering China Three Gorges UniversityYichang 443002China Hubei Field Observation and Scientific Research Stations for Water Ecosystem in three gorges Reservoir China Three Gorges UniversityYichang 443002China Engineering Research Center of Eco-Environment in three gorges Reservoir Region China Three Gorges UniversityYichang 443002China State Key Laboratory of Soi and Sustainable Agriculture Institute of Soil SciencesChinese Academy of SciencesNanjing 210008China

The use of trichlorphon in large quantities causes a large number of organic pollutants to enter water, sediments, and soils. Phyllosilicate minerals are considered effective adsorbents for organic pollutants. However, the adsorption behavior of organic pollutants on soil minerals affected by low-molecular-weight organic acids(LMWOAs) is not fully understood. In this study, the effect of LMWOAs on the adsorption behavior of trichlorphon on phyllosilicate minerals was investigated using a combination of adsorption measurements and molecular spectroscopic techniques(attenuated total reflection-Fourier transform infrared spectroscopy(ATR-FTIR) and X-ray photoelectron spectroscopy(XPS)). The adsorption of trichlorphon onto kaolinite(KAO) and montmorillonite(MON) was suppressed by increasing pH, indicating that electrostatic interaction played a key role in adsorption, especially at low pH. In the presence of citric acid(CA), there was an obvious promotion of trichlorphon adsorption on KAO and MON. In the presence of oxalic acid(OA), the adsorption of trichlorphon on KAO was promoted, whereas the adsorption on MON was inhibited, especially at pH 4.0. The presence of CA and OA increased the adsorption by increasing the exposure of hydrophobic sites of KAO and MON. The results from ATR-FTIR and XPS also indicated that the hydrophobic Si–O sites of phyllosilicate minerals were the preferred adsorption sites for trichlorphon in the presence of CA and OA, probably driven by the hydrophobic effect. However, the weak effect of OA on MON caused an increase in the electrostatic repulsion between MON and trichlorphon molecules, thus inhibiting adsorption. This study is significant for a deeper understanding of self-purification of soil and sediment systems in the presence of organic pollutants.

关键词： adsorption behavior citric acid hydrophobic effect organic pesticide organic pollutant organochlorine oxalic acid

A Catalog of ^(13)CO Clumps from the MWISP in l=10°–2.°

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Research in Astronomy and Astrophysics 2024年第5期24卷 218-234页

作者： Xiaoyu Luo Sheng Zheng Zhibo Jiang Zhiwei Chen Yao Huang Shuguang Zeng Xiangyun Zeng Rui Zhang Chen Long Guangrong Zhou Jinbo Hu Center for Astronomy and Space Sciences China Three Gorges UniversityYichang 443000China College of Electrical Engineering and New Energy China Three Gorges UniversityYichang 443000China College of Science China Three Gorges UniversityYichang 443000China Purple Mountain Observatory Chinese Academy of SciencesNanjing 210023China

In this study, we present a catalog of molecular clumps extracted from ^(13)CO(J=1-0) emission data of the Milky Way Imaging Scroll Painting(MWISP) project. The data covers the inner Milky Way within the longitude range10°≤l≤2.° and the latitude strip of |b|≤ 5°. 2.. The workflow for the extraction of clumps, namely Facet-SS-3DClump, consists of two parts: the identification of clump candidates and their verification. First, Facet-SS-3DClump employs FacetClumps to identify clump candidates. Subsequently, high-confidence clumps are obtained by cross-matching with the clumps detected by other algorithms, such as dendrogram. Second, these high-confidence clumps are used as prior knowledge to train a semi-supervised deep clustering approach, SS-3D-Clump, which is applied to verify clump candidates detected by FacetClumps, providing confidence levels for the molecular clumps. Finally, the catalog comprising 18,757 molecular clumps was obtained using Facet-SS-3D-Clump, and the catalog is 90% complete above 37 K km s^(-1). We observe a significant deviation of the mean Galactic latitude for clumps within |b|≤ 2. from the midplane, with b=-0°.110. We found that 82.3% of the dust clumps correspond to ^(13)CO clumps by matching with Herschel infrared dust clumps. In the future, Facet-SS-3D-Clump will be applied to detect ^(13)CO clumps in the entire MWISP data.

关键词： ISM molecules methods data analysis-stars formation

Effect of CeO_(2. nanoparticle sizes on catalytic performances of sulfated CeO_(2./Al_(2.O_(3) catalyst in NH_(3)-SCR reaction

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Journal of Rare Earths 2024年第3期42卷 515-522,I0004页

作者： Zhenghua Hu Dongqi An Lei Zhang Xuping Wang Siyong Fang Xinyun Tian Liu Qiu Jingfang Sun Tingzhen Li Lin Dong School of Environmental and Chemical Engineering Chongqing Three Gorges UniversityChongqing404000China Key Laboratory of Water Environment Evolution and Pollution Control in the three gorges Reservoir Chongqing Three Gorges UniversityChongqing404000China Jiangsu Key Laboratory of Vehicle Emissions Control Center of Modern AnalysisNanjing UniversityNanjing210093China

The sulfated CeO_(2./Al_(2.O_(3) catalysts with different sizes of CeO_(2.nanoparticles were prepared by using pure H_2. or acetic acid solution as impregnation solvent, and the influence of sizes of CeO_(2. nanoparticles on the catalytic performances of the sulfated CeO_(2./Al_(2.O_(3) catalyst was studied. The catalytic performance tests show that the sulfated CeO_(2./Al_(2.O_(3) catalyst using acetic acid solution as impregnation solvent has better catalytic activity and the resistance to K+poisoning than the sulfated CeO_(2./Al_(2.O_(3) catalyst using pure H_(2.O as impregnation solvent. The excellent catalytic performances can be ascribed to the smaller sizes of CeO_(2. nanoparticles in CeO_(2./Al_(2.O_(3) catalyst using acetic acid solution, which results in larger amount of adsorbed sulfate species, surface acid sites, surface active oxygen species and excellent redox property. These features are helpful for improving the catalytic performances of sulfated CeO_(2./Al_(2.O_(3) catalyst using smaller amount of CeO_(2. to cut the costs.

关键词： Cerium-based catalyst Nanoscale effect NH_(3)selective catalytic reaction Sulfation process Alkali metal poisoning Rare earths

Piezoelectric materials for pollutants degradation: State-of-the-art accomplishments and prospects

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Chinese Chemical Letters 2024年第4期35卷 61-72页

作者： Yuqing Zhu Haohao Chen Li Wang Liqun Ye Houle Zhou Qintian Peng Huaiyong Zhu Yingping Huang College of Materials and Chemical Engineering Key Laboratory of Inorganic Nonmetallic Crystalline and Energy Conversion MaterialsChina Three Gorges UniversityYichang 443002China Engineering Research Center of Eco-environment in three gorges Reservoir Region Ministry of EducationChina Three Gorges UniversityYichang 443002China College of Hydraulic&Environmental Engineering China Three Gorges UniversityYichang 443002China School of Chemistry and Physics Queensland University of TechnologyBrisbaneQLD 4001Australia

Piezoelectric catalysis, a new catalytic method, is widely used in the field of environmental sanitation, including waste water treatment and dye degradation. However, in the face of the growing environmental pollution problem, the efficiency of piezoelectric catalysis is still hampered by the stress variation in the natural environment. Therefore, it is particularly important to improve the catalytic efficiency of piezoelectric materials. We divide piezoelectric materials into two categories: inorganic piezoelectric materials and organic piezoelectric materials. Then the mainstream inorganic piezoelectric materials are divided into four subcategories, namely:(1) MTiO_(3)(M = Ba, Sr),(2. bi-class catalytic materials,(3) MoX_(2.(X = S,Se), and(4) ZnO piezoelectric materials. The mainstream organic piezoelectric materials are divided into PVDF and g-C_(3)N_(4)materials. At the same time, the above materials are summarized to explain the excellent performance of materials from the perspective of structure and piezoelectric principle. In addition,we summarized the modification methods that can be applied to piezoelectric materials:(1) Morphology methods,(2. composites with heterojunctions, and(3) surface modification. Finally, we summarized the prospects of piezoelectric materials in the field of environment and water treatment.

关键词： Ultrasound Cavitation Piezoelectric materials Degradation Organic pollutants