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Effects of pre-ozonation on organic matter removal by coagulation with IPF-PACl

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Journal of Environmental Sciences 2006年第3期18卷 453-458页

作者： LIU Hai-long WANG Dong-sheng shi bao-you WANG Min TANG Hong-xiao State Key Laboratory of Environmental Aquatic Chemistry Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 100085 China School of Environmental Science and Resources Shanxi University Taiyuan 030002 China School of Water Resources and Environmental Sciences China University of Geosciences Beijing 100083 China

Ozone plays an important role as a disinfectant and oxidant in potable water treatment practice and is increasingly being used as a pre-oxidant before coagulation. The purpose of this study is to obtain insight into the mechanisms that are operative in pre-ozonized coagulation. Effects ofpre-ozonation on organic matter removal during coagulation with IPF-PAC1 were investigated by using PDA （photometric disperse analysis）, apparent molecular weight distribution and chemical fractionation. The dynamic formation of flocs during coagulation process was detected. Changes of aquatic organic matter （AOM） structure resulted from the influence of pre-ozonation were evaluated. Results show that dosage of O3 and characteristics of AOM are two of the major factors influencing the performance of O3 on coagulation. No significant coagulation-aid effect of O3 was observed for all experiments using either A1C13 or PAC1. On the contrary, with the application of pre-ozonation, the coagulation efficiency of A1C13 was significantly deteriorated, reflected by the retardation of floc formation, and the removal decreases of turbidity, DOC, and UV254. However, if PACl was used instead of AlCl3, the adverse effects of pre-ozonation were mitigated obviously, particularly when the O3 dosage was less than 0.69 （mg O3/mg TOC）. The difference between removals of UV254, and DOC indicated that pre-ozonation greatly changed the molecular structure of AOM, but its capability of mineralization was not remarkable. Only 5% or so DOC was removed by pre-ozonation at 0.6--0.8 mg/L alone. Fractionation results showed that the organic products of pre-ozonation exhibited lower molecular weight and more hydrophilicity, which impaired the removal of DOC in the following coagulation process.

关键词： natural organic matter (NOM) fractionation pre-ozonation PACl coagulation

Transformations of particles, metal elements and natural organic matter in different water treatment processes

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Journal of Environmental Sciences 2007年第3期19卷 271-277页

作者： YAN Ming-quan WANG Dong-sheng shi bao-you WEI Qun-shan QU Jiu-hui TANG Hong-xiao State Key Laboratory of Environmental Aquatic Chemistry Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 100085 China

Characterizing natural organic matter （NOM）, particles and elements in different water treatment processes can give a useful information to optimize water treatment operations. In this article, transformations of particles, metal elements and NOM in a pilot-scale water treatment plant were investigated by laser light granularity system, particle counter, glass-fiber membrane filtration, inductively coupled plasma-optical emission spectroscopy, ultra filtration and resin absorbents fractionation. The results showed that particles, NOM and trihalomethane formation precursors were removed synergistically by sequential treatment of different processes. Preozonation markedly changed the polarity and molecular weight of NOM, and it could be conducive to the following coagulation process through destabilizing particles and colloids; mid-ozonation enhanced the subsequent granular activated carbon （GAC） filtration process by decreasing molecular weight of organic matters. Coagulation-flotation and GAC were more efficient in removing fixed suspended solids and larger particles; while sand-filtration was more efficient in removing volatile suspended solids and smaller particles. Flotation performed better than sedimentation in terms of particle and NOM removal. The type of coagulant could greatly affect the performance of coagulation-flotation. Pre-hydrolyzed composite coagulant （HPAC） was superior to FeCl3 concerning the removals of hydrophobic dissolved organic carbon and volatile suspended solids. The leakages of flocs from sand-filtration and microorganisms from GAC should be mitigated to ensure the reliability of the whole treatment system.

关键词： flotation fixed suspended solid trihalomethane formation potential ultra filtration resin absorbent fractionation

A novel weld-pool-length monitoring method based on pixel analysis in plasma arc additive manufacturing

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Advances in Manufacturing 2024年第2期12卷 335-348页

作者： bao-Ri Zhang Yong-Hua shi Bionic Robot Research Department Ji Hua LaboratoryFoshan528200GuangdongPeople’s Republic of China Guangdong Provincial Engineering Research Center for Special Welding Technology and Equipment School of Mechanical and Automotive EngineeringSouth China University of TechnologyGuangzhou510640People’s Republic of China

The real-time monitoring of the weld pool during deposition is important for automatic control in plasma arc additive *** obtain a high deposition accuracy,it is essential to maintain a stable weld pool *** this study,a novel passive visual method is proposed to measure the weld pool *** the proposed method,the image quality was improved by designing a special visual system that employed an endoscope and a *** also includes pixel brightness-based and gradient-based algorithms that can adaptively detect feature points at the boundary when the weld pool geometry *** algorithm can also be applied to materials with different solidification *** was performed to measure the real weld pool length in world coordinates,and outlier rejection was performed to increase the accuracy of the ***,tests were carried out on the intersection component,and the results showed that the proposed method performed well in tracking the changing weld pool length and was applicable to the real-time monitoring of different types of materials.

关键词： Plasma arc additive manufacturing(PAAM) Weld pool geometry Gradient analysis Real-time detection

Systematic study of the synthesis of heavy and superheavy nuclei in 48Ca-induced fusion-evaporation reactions

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Nuclear Science and Techniques 2024年第7期35卷 157-172页

作者： shi-Hao Zhu Tian-Liang Zhao Xiao-Jun bao Department of Physics Collaborative Innovation Center for Quantum EffectsKey Laboratory of Low Dimensional Quantum Structures and Quantum Control of Ministry of EducationHunan Normal UniversityChangsha410081China School of Nuclear Science and Technology Lanzhou UniversityLanzhou730000China School of Physics Xi’an Jiaotong UniversityXi’an710049China

We systematically studied the evaporation residue cross sections of ^(48)Ca-induced reactions on lanthanide and actinide target nuclei under the Dinuclear System(DNS)model framework to check the reliability and applicability of the *** produce new proton-rich Fl and Lv isotopes through hot fusion reactions in the superheavy element region with Z≥104,we utilized the reactions ^(48)Ca+^(236,238,239) Pu and ^(48)Ca+^(242,243,244,250) ***,owing to the detection limit of available equipment(0.1 pb),only 283Fl and 287−289Lv,which have the maximum evaporation residue cross section values of 0.149,0.130,9.522,and 0.309 pb,respectively,can be ***,to produce neutron-deficient isotopes of actinides near the proton drip line with Z=93−100,we attempted to generate the new isotopes(224−227Pu,228−232,237Cm)using the reactions ^(48)Ca+180,182,183 W and ^(48)Ca+^(184,186,187,192) *** maximum evaporation residue cross section values are 0.07,0.06,0.26,and 0.30 nb for the former set of reactions,and 1.96 pb,5.73 pb,12.16 pb,19.39 pb,54.79 pb,and 6.45 nb for the latter,*** results are expected to provide new information for the future synthesis of unknown neutron-deficient isotopes.

关键词： Dinuclear system(DNS)model Evaporation residue cross section Neutron-deficient isotopes

Evolution and function of residual solvent in polymer-Li_2B_(12)H_(12) composite solid electrolyte

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Rare Metals 2024年第8期43卷 3748-3757页

作者： Xiang-Yang Ye Ke-Pan bao Sai-Nan Luo Xin Li Tai-Qiang Chen Shui-Xin Xia Tao Yuan Yue-Peng Pang shi-you Zheng School of Materials and Chemistry University of Shanghai for Science and TechnologyShanghai 200093China Department of Materials Science and Engineering National University of SingaporeSingapore 119077Singapore

Composite solid electrolytes(CSEs) containing polymer matrices and inorganic fillers hold promise for the next generation of solid-state ***,the role of residual solvents in CSEs remains *** study investigated the evolution and function of the residual solvent in a polymer-Li_2B_(12)H_(12) CSE.A partial reaction occurred between Li_2B_(12)H_(12) and solvent N,N-dimethylformamide(DMF),which produced dimethylaminomethanol(DMAM) in the *** functional theory calculations have revealed that DMA M forms stronger hydrogen bonds with polyvinylidene fluoride chains than DMF,which can have a plasticizing effect on the polymer matrix,leading to lower crystallinity and quicker segment ***,this CSE exhibited improved Li-ion conducting properties,enabling the stable cycling of Li‖LiFePO_(4) solid-state *** study provided insights into the role of residual solvents in CSEs.

关键词： Composite solid electrolyte Residual solvent Lithium borohydride Plasticizing effect

General Method of Combining Grover and Simon for Attacking Block Ciphers

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China Communications 2024年第6期21卷 237-245页

作者： Fu Xiangqun bao Wansu shi Jianhong Li Tan Henan Key Laboratory of Quantum Information and Cryptography PLA SSF IEUZhengzhou 450001China Synergetic Innovation Center of Quantum Information and Quantum Physics University of Science and Technology of ChinaHefei 230026China

The compatibility of different quantum algorithms should be considered when these algorithms are *** this paper,the method of combining Grover and Simon is studied for the first time,under some preconditions or ***,we give two preconditions of applying Grover’s algorithm,which ensure that the success probability of finding the marked element is close to ***,based on these two preconditions,it is found out that the success probability of the quantum algorithm for FXconstruction is far less than ***,we give the design method of the Oracle function,and then present the general method of combining Grover and Simon algorithm for attacking block ciphers,with success probability close to 1.

关键词： block ciphers post-quantum crypto quantum algorithms

Resilience and response:Unveiling the impacts of extreme droughts on forests through integrated dendrochronological and remote sensing analyses

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Forest Ecosystems 2024年第4期11卷 491-501页

作者： Han shi Xi Peng Yong-Jiao Zhou Ai-Ying Wang Xue-Kai Sun Na Li Quan-Sheng bao Gude Buri Guang-you Hao CAS Key Laboratory of Forest Ecology and Silviculture Institute of Applied EcologyChinese Academy of SciencesShenyang110016China Daqinggou Ecological Research Station Institute of Applied EcologyChinese Academy of SciencesShenyang110016China University of Chinese Academy of Sciences Beijing100049China School of Life Science and Engineering Shenyang UniversityShenyang110044China Wudantala Forestry Forestry and Grassland Administration of Horqin Northeast CountyTongliao028100China

Extreme droughts are anticipated to have detrimental impacts on forest ecosystems,especially in water-limited regions,due to the influence of climate ***,considerable uncertainty remains regarding the patterns in species-specific responses to extreme ***,we conducted a study integrating dendrochronology and remote sensing methods to investigate the mosaic-distributed maple-oak(native)natural forests and poplar plantations(introduced)in the Horqin Sandy Land,Northeast *** assessed the impacts of extreme droughts on tree performances by measuring interannual variations in radial growth and vegetation *** results showed that precipitation and self-calibrated palmer drought severity index(scPDSI)are the major factors influencing tree-ring width index(RWI)and normalized difference vegetation index(NDVI).The severe droughts between 2000 and 2004 resulted in reduced RWI in the three studied tree species as well as led to NDVI reductions in both the maple-oak natural forests and the poplar *** RWI reached the nadir during the2000-2004 severe droughts and remained at low levels two years after the severe drought,creating a legacy *** contrast to the lack of significant correlation between RWI and scPDSI,NDVI exhibited a significant positive correlation with scPDSI indicating the greater sensitivity of canopy performance to droughts than radial ***,interspecific differences in RWI and NDVI responses were observed,with the fast-growing poplar species experiencing a more significant RWI decrease and more negative NDVI anomaly during severe droughts than native species,highlighting the species-specific trade-offs between drought resilience and growth *** study emphasizes the importance of combining tree-level radial growth with landscape-scale canopy remote sensing to understand forest resilience and *** study improves our understanding of forest responses to extreme drought and highlights species di

关键词： Introduced tree species Native tree species NDVI Severe drought Tree-ring width

Distribution and geochemical significance of alkylbenzenes for crude oil with different depositional environments and thermal maturities

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Petroleum Science 2024年第2期21卷 777-790页

作者： Bing-Kun Meng Dao-Fu Song Yuan Chen Sheng-bao shi School of Petroleum Engineering and Environmental Engineering Yan'an UniversityYan'an716000ShaanxiChina State Key Laboratory of Petroleum Resources and Prospecting College of GeosciencesChina University of PetroleumBeijing102249China

A total of 45 alkylbenzenes were detected and identified in crude oils with different depositional environments and thermal maturities from the Tarim Basin,Beibuwan Basin,and Songliao Basin using comprehensive two-dimensional gas chromatography time-of-flight mass spectrometry(GC×GCTOFMS).By analyzing the distribution characteristics of C0-C5alkylbenzenes,it is found that the content of some alkylbenzenes varies greatly in crude *** on the distribution characteristics of 1,2,4,5-tetramethylbenzene(Te MB)and 1,2,3,4-Te MB,the ratio of 1,2,4,5-Te MB to 1,2,3,4-Te MB is proposed to indicate the organic matter origin and depositional environment of ancient *** samples originated mainly from lower hydrobiont,algae,bacteria and source rocks deposited under reducing/anoxic conditions have low 1,2,4,5-/1,2,3,4-Te MB values(less than 0.6),while oil samples originated mainly from terrestrial higher plants and source rocks deposited under oxic/sub-oxic conditions have higher 1,2,4,5-/1,2,3,4-Te MB values(greater than 1.0).The significant difference of 1,2,4,5-/1,2,3,4-Te MB values is controlled by 1,2,4,5-Te MB content.1,2,4,5-Te MB content in oils derived from source rocks deposited in oxidized sedimentary environment(greater than 1.0 mg/g whole oil)is higher than that in oils from source rocks deposited in reduced sedimentary environment(less than 1.0 mg/g whole oil).1,2,4,5-/1,2,3,4-Te MB ratio might not or slightly be affected by evaporative fractionation,biodegradation and thermal maturity.1,2,4,5-/1,2,3,4-Te MB ratio and 1,2,4,5-Te MB content can be used as supplementary parameter for the identification of sedimentary environment and organic matter *** should be noted that compared to the identification of organic matter sources,the 1,2,4,5-/1,2,3,4-Te MB parameter is more effective in identifying sedimentary environments.

关键词： 1 2 4 5-Tetramethylbenzene GC×GC-TOFMS Organic matter origin Depositional environment

The Implantation and Transmission of Plague Culture by the Five Plague Gods in Shuilu Murals

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Chinese Medicine and Culture 2024年第3期7卷 185-191页

作者： YI bao ZHOU Qian shi Honglei Institute for History of Science and Technology Shanxi UniversityTaiyuan 030006China

The Five Plague Gods(五瘟神) in the Shuilu(水陆) murals from the Ming and Qing dynasties exemplify a distinctive manifestation of plague gods image developed under the pedigree of Taoist *** a significant system for expelling disasters in Shuilu,the depiction of the Five Plague Gods prominently merges human beings and *** shape form to a large extent,draws on the image of Nuo(傩),a figure reflecting an imagination of the host of plague *** terms of the numbers of gods,it aligns with the conceptual framework of Wu Xing(五行 the five elements),a foundational principle in traditional Chinese *** internal cultural connection highlights the means of plague prevention and control in China,as well as the external reflection of plague *** multi-dimensional interpretations with the double proof method,this article dissects the formation,core elements,and cultural characteristics of the beliefs in the Five Plague Gods reflected in the Shuilu murals,and transcends mere visual semantics,offering a deeper understanding of these complex cultural symbols.

关键词： Shuilu murals Five Plague Gods Plague culture Traditional Chinese medicine Wu Xing Religion