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Unexpected/contrary behavior of aerosol mass concentration in response to the individual components'concentration reduction in Kitakyushu,Japan

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Journal of Environmental Sciences 2024年第1期135卷 630-639页

作者： xi zhang Takuya Murakami Jinhe Wang Masahide Aikawa Faculty of Environmental Engineering The University of Kitakyushu1-1HibikinoWakamatsuKitakyushuFukuoka 808-0135Japan Resources and Environment Innovation Research Institute School of Municipal and Environmental EngineeringShandong Jianzhu UniversityJinan 250101China

In the suburbs of Kitakyushu,Japan,the inorganic aerosol mass concentration(IAM)was about 32.7μg/m^(3),with the aerosol pH of *** study the thermodynamics of aerosol when its individual components'concentration is reduced,sensitive tests were performed using the ISORROPIAⅡmodel,in which the seven control species—TNaCl,TNH_(4)^(+),TSO_(4)^(2-),TNO_(3)^(-),TMg^(2+),TK^(+),and TCa^(2+)—were taken into *** and inorganic aerosol pH after reducing TNaCl,TNO_(3)^(-),TMg^(2+),TK^(+),and TCa^(2+)responded linearly(0%≤concentration reduction ratio(CRR)≤100%,with the exception of 100%in TNaCl);the nonlinear variations of these two parameters could be observed by controlling TNH_(4)^(+)and TSO_(4)^(2-).Unexpected aerosol behavior occurred at 100%reduction of TNaCl,which was caused by the sudden increase of NO_(3)^(-),NH_(4)^(+),and aerosol liquid water content(ALWC);the increase of IAM was also observed after controlling TSO_(4)^(2-)(60%≤CRR≤100%)and TCa^(2+)(0%≤CRR≤100%),which was mainly related to the variation of ALWC driven by the response of CaSO_(4).Multiple regression analysis showed that ALWC was statistically and strongly related to the variations of NO_(3)^(-),Cl-,SO_(4)^(2-),HSO_(4)^(-),HNO_(3),and NH_(3)(P<0.05),with regression coefficients of 1.68,5.23,1.83,2.81,0.34,and 0.57,*** highest coefficient(5.23)was found for Cl^(-),revealing that sea salts significantly influenced particle ***,this study comprehensively investigated aerosol characteristics and inner responses for the reduction of components,which is of great significance for a better understanding of atmospheric chemistry in Kitakyushu,Japan.

关键词： Sensitive tests Reduction Gas-particle conversion process Aerosol liquid water content Sea salts

Prescribed Performance Tracking Control of Time-Delay Nonlinear Systems With Output Constraints

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IEEE/CAA Journal of Automatica Sinica 2024年第7期11卷 1557-1565页

作者： Jin-xi zhang Kai-Di Xu Qing-Guo Wang IEEE the State Key Laboratory of Synthetical Automation for Process Industries Northeastern UniversityShenyang 110819China Institute of Artificial Intelligence and Future Networks Beijing Normal UniversityZhuhai 519087 Guangdong Key Laboratory of Artificial Intelligence and Multi-Modal Data Processing Beijing Normal University-Hong Kong Baptist University United International CollegeZhuhai 519087

The problem of prescribed performance tracking control for unknown time-delay nonlinear systems subject to output constraints is dealt with in this paper. In contrast with related works, only the most fundamental requirements, i.e., boundedness and the local Lipschitz condition, are assumed for the allowable time delays. Moreover, we focus on the case where the reference is unknown beforehand, which renders the standard prescribed performance control designs under output constraints infeasible. To conquer these challenges, a novel robust prescribed performance control approach is put forward in this ***, a reverse tuning function is skillfully constructed and automatically generates a performance envelop for the tracking error. In addition, a unified performance analysis framework based on proof by contradiction and the barrier function is established to reveal the inherent robustness of the control system against the time delays. It turns out that the system output tracks the reference with a preassigned settling time and good accuracy,without constraint violations. A comparative simulation on a two-stage chemical reactor is carried out to illustrate the above theoretical findings.

关键词： Nonlinear systems output constraints prescribed performance reference tracking time delays

Variational Neural Inference Enhanced Text Semantic Communication System

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China Communications 2024年第7期21卷 50-64页

作者： zhang xi zhang Yiqian Li Congduan Ma xiao School of Electronics and Communication Engineering Sun Yat-Sen UniversityShenzhen 518107China Guizhou University State Key Laboratory of Public Big Data Guiyang 550025China Shenzhen Key Laboratory of Navigation and Communication Integration Shenzhen 518107China School of Computer Science and Engineering Sun Yat-Sen UniversityGuangzhou 510006China

Recently,deep learning-based semantic communication has garnered widespread attention,with numerous systems designed for transmitting diverse data sources,including text,image,and speech,*** efforts have been directed toward improving system performance,many studies have concentrated on enhancing the structure of the encoder and ***,this often overlooks the resulting increase in model complexity,imposing additional storage and computational burdens on smart ***,existing work tends to prioritize explicit semantics,neglecting the potential of implicit *** paper aims to easily and effectively enhance the receiver's decoding capability without modifying the encoder and decoder *** propose a novel semantic communication system with variational neural inference for text ***,we introduce a simple but effective variational neural inferer at the receiver to infer the latent semantic information within the received *** information is then utilized to assist in the decoding *** simulation results show a significant enhancement in system performance and improved robustness.

关键词： deep learning semantic communication variational neural inference

A Deep Mantle Source for the Late Neoarchean Metamorphosed Basalts in Eastern Hebei,North China Craton:Insights from Whole-Rock Geochemistry and Sm-Nd Isotopes,and Zircon U-Pb-Hf Isotopes

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Journal of Earth Science 2024年第1期35卷 29-40页

作者： Zhuang Li Chunjing Wei Chuan Yang xi zhang College of Geosciences China University of PetroleumBeijing 102249China MOE Key Laboratory of Orogenic Belts and Crustal Evolution School of Earth and Space SciencesPeking UniversityBeijing 100871China China Transport Telecommunications and Information Center Beijing 100011China

The basalts within the greenstone belt worldwide serve as an ideal target to decipher the nature of Archean mantle sources and further to extend the understanding of the early stages of Earth's *** provide important insights into the issues,we carried out a detailed investigation of whole-rock geochemistry and Sm-Nd isotopes,and zircon U-Pb-Hf isotopes for the Late Neoarchean metamorphosed basalts in eastern Hebei,North China Craton.U-Pb isotopic dating using the LA-ICPMS on zircons reveals that the basalts in eastern Hebei erupted at ca.2.48-2.51 Ga and subsequently experienced multiple regional metamorphic events at 2477 and 1798 Ma,*** metamorphosed basalts are featured by low SiO_(2),MgO,K_(2)O+Na_(2)O,and high Fe O contents,endowed with the subalkaline and high-Fe tholeiitic *** radiogenic initial Nd and Hf isotope values and correlations among V,Ni and Cr contents strongly imply that the basalts experienced significant clinopyroxene and olivine fractionation and minor crustal contamination during magma *** are also characterized by the relatively low total REE contents and exhibit significant depletions to moderate enrichments in the LREE contents,indicating the derivation from a deep mantle source in an Archean proto-mantle plume setting.

关键词： zircon U-Pb-Hf isotopes geochemistry Late Neoarchean basaltic magmatism North China Craton Archean proto-mantle plume

Syntheses and properties of associative acrylamide copolymers containing short hydrophobic chains used in a friction reducer for slick-water fracturing

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Petroleum Science 2024年第3期21卷 1889-1901页

作者： Ya-xing Dai xian-Li zhang Si-Yuan Liu Feng-Run-Ze zhang Yi-xi zhang Yu-Tong Sang Jing-xi Zheng Zhao-Sheng Liu Peng zhang College of Chemistry and Chemical Engineering Chongqing University of Science and TechnologyChongqing401331China College of Ecology and Environment Chongqing Resources and Environmental Protection of UniversityChongqing401331China China China Property Project Department of Dezhou Mining Property Service CenterShengli Oilfield Company of SinopecDezhou253000ShandongChina

Two allyldimethylalkyl quaternary ammonium salt(AQAS)monomers,N,N-dimethylallylphenylpropylammonium bromide(AQAS1)and N,N-dimethylallylnonylammonium bromide(AQAS2),were synthesized and used to prepare modified polyacrylamide *** new drag reducers were synthesized from acrylamide(AM),sodium acrylate(Na AA)and a cationic modified monomer(AQAS1 or AQAS2)via aqueous solution polymerization,and the copolymers were named P(AM/Na AA/AQAS1)and P(AM/Na AA/AQAS2),*** structures of the drag reduction agents were confirmed by IR and1H NMR *** molecular weight(Mw)of P(AM/Na AA/AQAS1)was 1.79×10^(6)g/*** the copolymer concentration was 1000 mg/L and the flow rate was 45 L/min,in fresh water the highest drag reduction rate was 75.8%,in 10,000 mg/L Na Cl solution the drag reduction rate decreased to 72.9%.The molecular weight of P(AM/Na AA/AQAS2)was 3.17×10^(6)g/*** the copolymer concentration was500 mg/L and the flow rate was 45 L/min,the drag reduction rate reached 75.2%,and in 10,000 mg/L Na Cl solution the drag reduction rate was 73.3%,decreased by approximately 1.9%.The drag reduction rate for partially hydrolyzed polyacrylamide(HPAM)was also investigated,and the results showed that the drag reduction rates for 500 and 1000 mg/L HPAM solutions were merely 43.2%and 49.0%in brine,*** with HPAM,both of the above copolymers presented better drag reduction capacities.

关键词： Shale gas Slick water Drag reducer Modified monomer Copolymerization

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On Depolymerization

CCS Chemistry 2024年第2期6卷 297-312页

作者： Bo Qin xi zhang College of Chemistry and Chemical Engineering Hunan UniversityChangsha 410082 Department of Chemistry Tsinghua UniversityBeijing 100084

Polymers have become an essential part of modern life and the global economy on account of their costeffectiveness and versatile ***,most postconsumer polymer wastes are unrecycled,leading to environmental pollution and resource ***,as an efficient chemical recycling approach,holds great promise in establishing a circular polymer *** this review,we attempt to highlight recent and significant advancements in depolymerization *** key research topics are discussed:(1)depolymerization of commodity polymers to produce reusable monomers and high-value chemicals;(2)depolymerization of intrinsically depolymerizable *** is anticipated that this review will reflect the present status and future trends of this rapidly evolving realm of depolymerization.

关键词： depolymerization chemical recycling sustainable polymers circular polymer economy catalysis dynamic covalent chemistry

DMPP mitigates N_(2)O and NO productions by inhibiting ammonia-oxidizing bacteria in an intensified vegetable field under different temperature and moisture regimes

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Pedosphere 2024年第3期34卷 652-663页

作者： xi zhang xintong XU Chenyuan WANG Qianqian zhang Yubing DONG Zhengqin xiONG Jiangsu Key Laboratory of Low Carbon Agriculture and GHGs Mitigation College of Resources and Environmental SciencesNanjing Agricultural UniversityNanjing 210095(China) Department of Soil Science of Temperate Ecosystems Department of Agricultural Soil ScienceGeorg-August University of GottingenGottingen 37077(Germany) State Key Laboratory of Subtropical Silviculture Zhejiang A&F UniversityHangzhou 311300(China) Huaiyin Institute of Agricultural Sciences of Xuhuai Region in Jiangsu Jiangsu Academy of Agricultural SciencesHuai’an 223001(China)

Vegetable soils with high nitrogen input are major sources of nitrous oxide(N_(2)O)and nitric oxide(NO),and incorporation of the nitrification inhibitor 3,4-dimethylpyrazole phosphate(DMPP)into soils has been documented to effectively reduce ***,the efficiency of DMPP in terms of soil N_(2)O and NO mitigations varies greatly depending on soil temperature and moisture ***,further evaluations of DMPP efficiency in diverse environments are required to encourage widespread application.A laboratory incubation study(28 d)was established to investigate the interactive effects of DMPP,temperature(15,25,and 35?C),and soil moisture(55% and 80% of water-holding capacity(WHC))on net nitrification rate,N_(2)O and NO productions,and gene abundances of nitrifiers and denitrifiers in an intensive vegetable *** showed that incubating soil with 1%DMPP led to partial inhibition of the net nitrification rate and N_(2)O and NO productions,and the reduction percentage of N_(2)O production was higher than that of NO production(69.3%vs.38.2%)regardless of temperature and soil moisture *** increased temperatures promoted the net nitrification rate but decreased soil N_(2)O and NO *** moisture influenced NO production more than N_(2)O production,decreasing with the increased moisture level(80%).The inhibitory effect of DMPP on cumulative N_(2)O and NO productions decreased with increased temperatures at 55%***,the inhibitory effect of DMPP on cumulative N_(2)O production increased with increased temperatures at 80%*** on the correlation analyses and automatic linear modeling,the mitigation of both N_(2)O and NO productions from the soil induced by DMPP was attributed to the decreases in ammonia-oxidizing bacteria(AOB)amoA gene abundance and NO_(2)^(-)-N ***,our study indicated that DMPP reduced both N_(2)O and NO productions by regulating the associated AOB amoA gene abundance and NO_(2)^(-)-N concentra

关键词： 3,4-dimethylpyrazole phosphate environment condition gene abundance nitrification inhibitor nitrite accumulation soil water content

Variation characteristics of acid rain in Zhuzhou,Central China over the period 2011-2020

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Journal of Environmental Sciences 2024年第4期138卷 496-505页

作者： Jiahao Ren Liquan Zhu xi zhang Yuqian Luo Xuecai Zhong Bowen Li Yuwen Wang Kai zhang State Key Laboratory of Environmental Criteria and Risk Assessment Chinese Research Academy of Environmental SciencesBeijing 100012China Zhuzhou Environment Monitoring Center Zhuzhou 412000China Faculty of Environmental Engineering The University of Kitakyushu1–1 HibikinoWakamatsuKitakyushuFukuoka 808-0135Japan College of Natural Resources and Environment South China Agricultural UniversityGuangzhou 510642China

Zhuzhou was one of the most polluted cities in China with the serious acid *** to the implementation of air pollution control measures from 2016 to 2018,the acid rain pollution in this city has *** order to understand the recent situation,a comprehensive study on the acid rain was carried out from January 2011 to December *** pH values during the study period varied from 3.3 to 7.5,with a volume-weighted mean value of *** predominant acidic components of the precipitation were SO_(4)^(2-)and NO_(3)^(-),accounting for 89.3% of the total *** ratio of non-sea-salt SO_(4)^(2-)to NO_(3)^(-)showed a decreasing trend,revealing that the pollution type of acid rain changed from sulfuric acid type to sulfuric acid and nitric acid compound *** correlation analysis(p<0.05)showed that SO_(4)^(2-)was positively correlated with NH_(4)^(+),Ca^(2+),and Mg^(2+);hence,it predominated in precipitation as(NH_(4))_(2)SO_(4),NH_(4)HSO_(4),CaSO_(4),and MgSO_(4).Significant positive correlation of Ca^(2+)with Mg^(2+)shows that they may originated mainly from *** positive correlation between SO_(4)^(2-)and F^(-)and Cl^(-)indicate that their source may be related to the non-ferrous metal smelting industry in *** correlation analysis shows that emissions from the non-ferrous metal smelting industry in the area have a large significant on SO_(4)^(2-)and F^(-)in precipitation,while Cl^(-)may still be emitted from other anthropogenic sources.

关键词： Acid rain pH Chemical composition Neutralization factor Correlation analysis

End-Triassic storm deposits in the lacustrine Sichuan Basin and their driving mechanisms

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Science China Earth Sciences 2024年第7期67卷 2383-2400页

作者： Jianli ZENG Tingshan zhang Mihai Emilian POPA Yongdong WANG xi zhang Liqin LI Yuanyuan XU Ning LU xiaoqing zhang School of Geoscience and Technology Southwest Petroleum University Chengdu 610500China Sichuan Key Laboratory of Natural Gas Geology Southwest Petroleum University Chengdu 610500China Faculty of Geology and Geophysics Doctoral Schoolof Geology Laboratory of Palaeontology University of Bucharest.Bucharest 010041Romania Nanjing Institute of Geology and Palaeontology Chinese Academy of Sciences Nanjing 210008China University of Chinese Academy of Sciences NanjingNanjing 210008China University of Chinese Academy of Sciences Beijing 100049China

Storm deposits or tempestites are event sequences formed by storms,requiring at least a water temperature of 26.5℃.While inland lakes are unlikely to form storm deposits because of their limited width and water *** Upper Triassic Xujiahe Formation in the Sichuan Basin is a set of coal-bearing,clastic sequences with dominant sedimentary facies varying from braided river delta to lacustrine settings,with storm deposits widely *** the Zilanba of Guanyuan area,in situ tree trunks on a palaeosol surface in Member Vof the Xujiahe Formation provide new evidence of a storm *** fallen-down directions of nine in situ tree trunks were predominant in the NW direction,contrary to the palaeocurrent direction of the underlying strata,suggesting that the southeasterlies prevailed during the end-Triassic in the northern Sichuan *** mud clasts were frequently recorded in sandstones of the Xujiahe Formation,as well as in the xindianzi *** mud clasts showed a rip-up or a plastic deformation with upside-down V-shapes,were capped on an erosional surface,showed no transport traces and were therefore interpreted as a storm lag *** megamonsoonal climate prevailed during the Late Triassic,although the megamonsoons themselves could not generate a storm deposition in the Xujiahe Formation due to its low maximum surface wind *** driving mechanism for generating storm deposits in the Xujiahe Formation is suggested to be tropical cyclones over the Tethys Ocean moving eastward,further landfalling on the western margin of the Sichuan *** of storm events in the circum-Tethys region show a widespread storm surge in low latitudes during the *** storm deposits at the top of the Xujiahe Formation represent a sedimentary response to the end-Triassic hyperthermal event.

关键词： Sichuan Basin End-Triassic Xujiahe Formation Storm deposits

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