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^(1.7)Cs Redistribution in Thin Stony Soil of a Carbonate Rock Slope in Southwest china

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Pedosphere 2011年第1期21卷 37-45页

作者： li Hao ZHANG Xin-Bao {1. Kc-lin WEN An-Bang institute of Mountain Hazards and Environment Chinese Academy of Sciences Chengdu 610041 (China) Graduate University Chinese Academy of Sciences Beijing 100049 (China) state {1. laboratory of environmental geochemistry Institute of Geochemistry Chinese Academy of Sciences Guiyang 550002 (China) institute of Subtropical Agriculture Chinese Academy of Sciences Changsha 410125 (China)

The fallout radionuclide cesium-1.7(1.7 Cs) has been widely employed as a tracer for assessment of soil loss from thick uniform soils;however,few studies have been conducted on thin stony soils on slopes underlain by carbonate rocks which are widely distributed in karst *** derived from 1.7 Cs measurement of soil samples collected along a carbonate rock slope with thin stony soil where neither soil erosion nor deposition occurred was used to investigate the characteristics of 1.7 Cs redistribution in a karst area of Southwest *** results indicated that the 1.7 Cs inventories of the surface soil on the slope studied were much lower than that of the local 1.7 Cs reference inventory and the 1.7 Cs activities were much higher than those on slopes with thick uniform *** spatial distribution of 1.7 Cs inventories was characterized by considerable *** high 1.7 Cs depletion in the stony soil of the slope studied was mainly because a considerable proportion of the fallout input of 1.7 Cs could be lost with runoff and the dissolution of carbonate particles in the soil promoted the loss of 1.7 *** demonstrated that the rates of soil loss could not be estimated from the degree of depletion of the 1.7 Cs inventory relative to the local reference inventory for the thin stony soil of the rocky slope underlain by carbonate rocks in the study area in the way that has been widely used in areas with thick uniform soils.

关键词： carbonate dissolution, ^1.7Cs fallout, ^1.7Cs inventory karst area runoff

Boron isotopic fractionation in laboratory inorganic carbonate precipitation:Evidence for the incorpora-tion of B(OH)_3 into carbonate

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Science china Earth {1. 2008年第12期51卷 1776-1785页

作者： XIAO YingKai1,2, li Hualing1,3, liU WeiGuo4, wang XiuFang1 & JIANG ShaoYong5 1 Qinghai institute of Salt Lakes, chinese academy of sciences, Xining 810008, china 2 state key laboratory of environmental geochemistry, institute of geochemistry, chinese academy of sciences, guiyang 550002, china 3 Nanjing institute of Geology and Mineral Resources, Nanjing 210016, china 4 state key laboratory of Loess and Quaternary Geology, institute of Earth Environment, chinese academy of sciences, Xi’an 710075, china 5 state key laboratory for Mineral Deposits Research, Department of Earth sciences, Nanjing University, Nanjing 210093, china Qinghai institute of Salt Lakes Chinese Academy of Sciences Xining China state {1. laboratory of environmental geochemistry Institute of Geochemistry Chinese Academy of Sciences Guiyang China Nanjing institute of Geology and Mineral Resources Nanjing China state {1. laboratory of Loess and Quaternary Geology Institute of Earth Environment Chinese Academy of Sciences Xi’an China state {1. laboratory for Mineral Deposits Research Department of Earth Sciences Nanjing University Nanjing China

A laboratory inorganic carbonate precipitation experiment at high pH of 8.96 to 9.34 was conducted, and the boron isotopic fractionations of the precipitated carbonate were measured. The data show that boron isotopic fractionation factors (αcarb-3) between carbonate and B(OH)3 in seawater range 0.937 and 0.965, with an average value of 0.953. Our results together with those reported by Sanyal and collabo-rators show that the αcarb-3 values between carbonate and B(OH)3 in solution are not constant but are negatively correlated with the pH of seawater. The measured boron isotopic compositions of carbonate precipitation (δ1.Bcarb) do not exactly {1.e on the best-fit theoretical δ 1.B4-pH curves and neither do they exactly parallel any theoretical δ 1.B4-pH curves. Therefore, it is reasonable to argue that a changeable proportion of B(OH)3 with pH of seawater should also be incorporated into carbonate except for the dominant incorporation of B(OH)4- in carbonate . Hence, in the reconstruction of the paleo-pH of sea-water from boron isotopes in marine biogenic carbonates, the use of theoretical boron isotopic frac-tionation factor (α4-3) between B(OH)4- and B(OH)3 is not suitable. Instead, an empirical equation should be estab{1.shed.

关键词： boron isotopic fractionation biogenic carbonate B(OH)3 incorporation

Sulfur isotopic composition of Yellow and Yangtze rivers and uplift of the Qinghai-Xizang Plateau

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chinese Science Bulletin 1999年第S2期44卷 120-122页

作者： hong yetang, GU Ailiang, wang hongwei and hong Bing state key laboratory of environmental geochemistry, institute of geochemistry, chinese academy of sciences, guiyang 550002, china state {1. laboratory of environmental geochemistry Institute of Geochemistry Chinese Academy of Sciences Guiyang 550002 China

THE sulfur isotopic composition of dissolved sulfate in any rivers has been recognized as a mixture of thesulfur derived from the soil, bedrock and the atmosphere. The measurement of the sulfur isotopic composition in a river water can provide background information on the biogeochemical cycling of sulfur in theriver basin. So far, however, {1.ttle work has been done on sulfur isotope in the watersheds of the majorrivers of the world. In particular, no information of the sulfur isotope of the major rivers in Asian conti-

关键词： sulfur isotopic composition Yellow and Yangtze rivers uplift Qinghai-Xizang Plateau.

Regulation mechanism of EM parameters in natural ferrite and its application in microwave absorbing materials

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Science china(Technological {1.) 2006年第1期49卷 38-49页

作者： ZHENG Yongchun1,2, wang Shijie2, FENG Junming2, li Chunlai1, OUYANG Ziyuan1,2, liU Jianzhong1 & li Xiaobiao2 1. National Astronomical Observatories, chinese academy of sciences, Beijing 100012, china 2. state key laboratory of environmental geochemistry, institute of geochemistry, chinese academy of sciences, guiyang 550002, china National Astronomical Observatories Chinese Academy of Sciences Beijing China state {1. laboratory of environmental geochemistry Institute of Geochemistry Chinese Academy of Sciences Guiyang China

Electromagnetic (EM) parameters (ε ′, ε ″, μ ′, μ″ ) of several M2+Fe2O4 and Fe2O3 type natural ferrites with different geological occurrences are measured in this pa-per. The measurement results show that EM parameters of a magmatic-occurring natural ferrite is very different from other types occurring from sedimentary-metamorphic iron deposit, hydrothermal vein iron deposit, outer contact of magmatic iron deposit. It has potential to be used as magnetic absorbent in microwave absorbing materials. After min-eral separation and concentration, this magmatic-occurring natural ferrite was processed into type A ferrite absorbent. Type A natural ferrite absorbent is a kind of magnetic material with low dielectric constants, high magnetic conductivity and high EM loss. Its EM pa-rameters are ε ′ = 58.60, ε ″ = 1..0, μ ′ = 1.2-1.5, μ ″ = 1.0-1.2, respectively. In order to illuminate the regulation mechanism of EM parameters, we studied the chemical and mineral composition of type A ferrite absorbent. There is high concentration of natural impurities, which regulate the EM parameters of type A ferrite greatly. For comparison, the other types of natural ferrite, single-phase magnetite and two-phase iron minerals (ilmen-ite and magnetite), have few impurity. Thus regulation mechanism of EM parameters was absent in these ferrites. As a result, the regulation of EM parameters is advantageous to develop type A natural ferrite as excellent absorbent, lowers the reflectivity coefficients and enhances the absorbing efficiency of MAM made from it. Furthermore, the impurities in type A natural ferrite and its effects on EM parameters are very difficult to simulate in the synthesize ferrite. The carbonyl-iron powder is another kind of absorbent that is used ex-tensively in MAM. To compare the absorbing properties of these two absorbent, type A natural ferrite and carbonyl-iron powder were mixed with rubber and processed into mi-crowave absorbing sheets with the same procedures and tec

关键词： natural impure ferrite, complex permittivity, complex permeability, microwave absorbing materials.

Multimodal Machine Learning Guides Low Carbon Aeration Strategies in Urban Wastewater Treatment

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Engineering 2024年第5期36卷 51-62页

作者： hong-{1.g wang yu-Qi wang xu wang Wan-Xin Yin Ting-Chao yu {1.-Hao xue Ai-Jie wang state {1. laboratory of Urban Water Resource and Environment School of Civil and Environmental EngineeringHarbin Institute of Technology(Shenzhen)Shenzhen 518055China key {1. of Drinking Water Safety and Distribution Technology of Zhejiang Province College of Civil Engineering and ArchitectureZhejiang UniversityHangzhou 310058China

The potential for reducing greenhouse gas(GHG)emissions and energy consumption in wastewater treatment can be realized through intelligent control,with machine learning(ML)and multimodality emerging as a promising ***,we introduce an ML technique based on multimodal strategies,focusing specifically on intelligent aeration control in wastewater treatment plants(WWTPs).The generalization of the multimodal strategy is demonstrated on eight ML *** results demonstrate that this multimodal strategy significantly enhances model indicators for ML in environmental science and the efficiency of aeration control,exhibiting exceptional performance and *** random forest with visual models achieves the highest accuracy in forecasting aeration quantity in multimodal models,with a mean absolute percentage error of 4.4%and a coefficient of determination of *** testing in a full-scale plant reveals that the multimodal model can reduce operation costs by 1..8%compared to traditional fuzzy control *** potential application of these strategies in critical water science domains is *** foster accessibility and promote widespread adoption,the multimodal ML models are freely available on GitHub,thereby eliminating technical barriers and encouraging the application of artificial intelligence in urban wastewater treatment.

关键词： Wastewater treatment Multimodal machine learning Deep learning Aeration control Interpretable machine learning

Organic stoichiometric cocrystals with a subtle balance of charge-transfer degree and molecular stacking towards high-efficiency NIR photothermal conversion

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chinese Chemical Letters 2024年第10期35卷 180-186页

作者： Jieqiong xu {1. chen Shengkai li Qian chen Tao wang Yadong Shi Shengyong Deng Mingde li Peifa Wei Zhuo chen institutes of Physical Science and Information Technology Key Laboratory of Structure and Functional Regulation of Hybrid Materials of Ministry of EducationAnhui Graphene Engineering LaboratoryAnhui UniversityHefei 230601China Molecular Science and Biomedicine laboratory(MBL).{1. key laboratory of Chemo/Biosensing and Chemometrics College of Chemistry and Chemical EngineeringCollege of BiologyAptamer Engineering Center of Hunan ProvinceHunan UniversityChangsha 410082China Department of Chemistry and key {1. for Preparation and Application of Ordered Structural Materials of Guangdong Province Shantou UniversityShantou515063China

Charge-transfer(CT)stoichiometric cocrystals are promising choice of organic materials for unveiling the structure-property ***,due to the contradiction between large CT degree required for strong NIR absorption and flexible molecular stacking,construction of stoichiomorphism-based cocystals with near-infrared(NIR)photothermal property remains ***,the first example of stoichiomorphism-based photothermal cocrystals were accomp{1.shed through the adaptive assembly of 3,3,5,5-tetramethylbenzidine(TMB)donor and 1.2,4,5-tetracyanobenzene(TCNB)*** selective cocrystal{1.zation could be controlled by varying the donor-acceptor stoichiometries via a surfactantassisted method,resulting in two cocrystals with 1.1.T1.1.and 1.2(T2C1.*** absorbance intensity of T1.1.at 808 nm was nearly twice that of T2C1.while the photothermal conversion efficiency(PCE)of the former was 60.3%±0.6%,approximately 80%of that for the latter(75.5%±2.6%),which might be caused by the different intermolecular interactions in distinct molecular stacking ***,both excellent PCEs of stoichiometric cocrystals were attributed to the nonradiative transition process,including internal conversion and charge dissociation processes,as elucidated by femtosecond transient absorption spectroscopy ***,T1.1.was used as an NIR heater for preparing agarose-based photothermal hydrogel,showing great potential for {1.ght-controlled in-situ *** strategy of balancing the CT degree and molecular packing orientation not only uncovered the relationship between stoichiometric stacking and photothermal property,but also provided an opportunity to develop advanced organic optoelectronic materials.

关键词： Charge-transfer cocrystal Stoichiometric stacking Crystal growth Photothermal conversion In-situ gelation

Strengthening and toughening styrene-butadiene rubber by mechanically interlocked cross-links

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Science china Chemistry 2024年第10期67卷 3414-3422页

作者： yuanhao {1. li Yang lin cheng Jun Zhao Ruixue Bai wenbin {1. Shaolei Qu Zhaoming Zhang Wei yu xuzhou Yan School of Chemistry and Chemical Engineering Frontiers Science Center for Transformative MoleculesShanghai Key Laboratory of Electrical Insulation and Thermal AgingShanghai Jiao Tong UniversityShanghai 200240China

Styrene-butadiene rubber(SBR)is an indispensable material in modern society,and the necessity for enhanced mechanical properties in SBR persists,particularly to withstand the rigors of challenging environmental *** surmount the {1.mitations of conventional cross-linking modes,mechanical bonds stabi{1.zed by host-guest recognition are incorporated as the cross-linking points of SBR to form mechanically interlocked networks(MINs).Compared with covalently cross-linked network,the representative MIN exhibits superior mechanical performance in terms of elongation(1.92%)and breaking strength(4.6 MPa),whose toughness has surged by 1. *** of host-guest recognition and subsequent s{1.ding motion provide an effective energy dissipation mechanism,and the release of hidden length is also beneficial to enhance ***,the introduction of the rotaxane cross-links made the network more p{1.able and possess damping and elastic properties,which can return to initial state with one minute rest *** aspire that this direct introduction method can serve as a blueprint,offering valuable insights for the enhancement of mechanical properties in conventional commercial polymer materials.

关键词： mechanically interlocked molecules host-guest chemistry styrene-butadiene rubber mechanical properties dynamic materials

Research progress on simulation of multiscale mass transfer processes in gas-solid system by computational mass transfer

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Particuology 2024年第7期90卷 478-492页

作者： xu {1. Yaohui wang Leifu {1. Runye Zhang Hailun Ren wenbin {1. Zhong{1. Tang Donghui Zhang The Research Center of Chemical Engineering School of Chemical Engineering and TechnologyTianjin UniversityTianjin 300072China The Department of Chemical Engineering Tianjin Renai CollegeTianjin 301636China Collaborative Innovation Center of Chemical Science and Engineering(Tianjin) School of Chemical Engineering and TechnologyTianjin UniversityTianjin 300072China

Particle-fluid system is one of the most popular systems in chemical *** to complex interface structure and high-velocity turbulence,the momentum and mass transfer exhibit nonlinear characteristics,which pose a great challenge for further study and *** solve this problem,computational mass transfer(CMT)emerged and has been proved to be effective in deeply exploring the mass transfer behavior of particle-fluid ***,this paper reviews recent gas-so{1.d numerical studies of turbulence issues from empirical to theoretical,then discusses interphase mass transfer rate models and the interfacial interaction ***,the present study particularly reviews researches on mass transfer process of fixed and fluidized regime by CMT,providing re{1.able analysis of turbulent anisotropy diffusivity as well as multiscale structure and presenting theoretical instruction for the industrial optimization of mass transfer processes in chemical engineering.

关键词： Fixed bed Fluidized bed Computational mass transfer Turbulent mass diffusion Multiscale Anisotropy

Characteristics of rare earth elements in soils in Guizhou carbonate region

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chinese Science Bulletin 1999年第S2期44卷 115-116页

作者： YAN Chongling~(1,2), hong yetang~1, wang Shijie~1, FU Shunzhen~2, ZHU keyong~2 and WU Shanqi~2 1. state key laboratory of environmental geochemistry, chinese academy of sciences, guiyang 550002, china 2. Guizhou institute of environmental Protection, guiyang 550002, china state {1. laboratory of environmental geochemistry Chinese Academy of Sciences Guiyang 550002 China Guizhou institute of {1. Protection Guiyang 550002 China

IN recent years, rare earth element (REE) being used in agriculture has gained greater progress and madeus reach some common views. The centent of REE (especially soluble REE) in soils has significantcorrelation with that of REE plant absorbed from soil. Therefore, it is very necessary to clarify contentvariation and background values of REE (especially soluble REE ) from the angles of relation of supplyand demand between soil and plants, for reasonably using REE and formulating relevant health standardin the region, avoiding excessive using REE and taking up soil environmental capacity of REE to result insoil or water-body polluted and sometime for researching rock weathering, soil-forming process and soilclassification in the region. This note deals with characteristics of content and distribution of REE andsoluble REE in soils of Guizhou carbonate region.

关键词： rare earth element soil, Carbonate area, Guizhou.