检索结果-南通市图书馆

ADSORPTION OF humic substanceS BY MACRO WEAKLY BASIC IONEXCHANGE RESIN AND THEIR EFFECTS ON REMOVAL OF Cu^(2+) AND Pb^(2+)

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Polymer Science 2010年第3期28卷 427-435页

作者：李爱民 State Key Laboratory of Pollution Control and Resource Reuse School of the Environment Nanjing University Research Center of Organic Toxic substance Control and Resource Reuse of Jiangsu Province

Adsorption of humic, tannic and gallic acids by a macro weakly basic ion-exchange resin JN-01 was studied. The adsorption capacity of this resin for gallic and tannic acids is much higher than that for humic acid, which can be explained on the basis of both their molecular size and ionization degree. Furthermore, humic acid is separated into different components with molecular weight in the range from 2000 Da to 100000 Da by ultra-filter, and their adsorption isotherms on resin JN-01 indicate that humic acid＇s molecular weight is an important factor which makes significant influence on adsorption. Finally, changes in the amount of Cu^2＋ and Pb^2＋ adsorbed on resin JN-01 as a function of the concentration of each of these three acids were studied. A large increase in the heavy metal ions uptake is observed in the presence of humic substance, such advantages are due to the interactions between the heavy metal ions and the unbound functional groups of the adsorbed organic acids.

关键词： Adsorption humic substance Macro weakly basic ion-exchange resin Removal Heavy metal

Enhancement of Phosphorus Solubility by humic substances in Ferrosols

在线全文

学校读者我要写书评

暂无评论

Pedosphere 2008年第4期18卷 533-538页

作者： HUA Quan-Xian LI Jian-Yun ZHOU Jian-Min WANG Huo-Yan DU Chang-Wen CHEN Xiao-Qin Zhengzhou University Zhengzhou 450001 （China） State Key Laboratory of Soil and Sustainable Agriculture Institute of Soil Science Chinese Academy of Sciences Nanjing 210008 （China） Zhengzhou Institute of Aeronautical Industry Management Zhengzhou 450015 （China）

An investigation was conducted to study the effect of humic substance (HS) on the phosphorus (P) solubility in acidic soil. The soil (2.5 g), HS (0, 0.5, and 2.5 g), and P as monocalcium phosphate (0.31 and 1.25 g P kg-1 soil) were mixed with 50 mL distilled water and two different sequences of adding HS and P were used. The results indicated that the P concentration in water and 0.01 mol L-1 CaCl2 solution increased with increasing amounts of humic substance. The concentrations of Fe and Al were also increased. However, Olsen P decreased with increasing amount of humic substance. Water-soluble P concentrations from P rates at 0.31 and 1.25 g P kg-1 soil in the treatment with 0.5 g (2.5 g) humic substance addition were 360% and 70% (500% and 90%) higher, respectively, than those in the treatment with no humic substance addition. P extracted by 0.01 mol L-1 CaCl2 in the treatments with 0.5 and 2.5 g humic substance addition was increased by 400% and 540%, respectively, compared with that in the treatment without humic substance at the rate of 0.31 g P kg-1 soil, while the corresponding P concentrations were increased by 80% and 90% at the rate of 1.25 g P kg-1 soil. The order of mixing humic substance and phosphate did not significantly affect desorbed P and labile P extracted with CaCl2.

关键词： aluminium Ferrosols humic substance iron phosphorus

Competitive Complexation of Copper and Zinc by Sequentially Extracted humic substances from Manure Compost

在线全文

学校读者我要写书评

暂无评论

Agricultural Sciences in China 2008年第10期7卷 1253-1259页

作者： LIU Shuai WANG Xu-dong LU Li-lan DIAO Shi-rong ZHANG Jun-feng College of Resources and Environment Northwest A ＆ F University Yangling 712100 P.R.China

Chicken manure with similar content of copper and zinc was changes of organic carbon and humus substance complexed chosen to conduct a composting experiment to investigate the copper （HS-Cu） and zinc （HS-Zn）, which were extracted by water （H2O）, sodium hydroxide （NaOH）, and sodium pyrophate-NaOH mixture （Na4P2O7-NaOH）, sequentially. Distributions of copper and zinc in fulvic acids （FA） and humic acids （HA） in the three extracts were studied. During manure composting, the concentrations of copper and zinc increased from about 500 mg kg^-1 in the raw material to 1 100 mg kg^-1 in the final products. HS-Cu in H2O, NaOH, and Na4P2O7-NaOH extracts occupied 6.7, 26.7, and 19% averagely of total copper and HS-Zn represented 2.7, 13.7, and 17% averagely of total zinc in compost, respectively. In water extracts, both HA and FA mainly complexed with Cu and the mole ratio of Cu to Zn was 2.8 in HA fractions and was 2.6 in FA fractions, respectively. HA mainly complexed with copper, so that the ratios of HA-Cu to HA-Zn averaged 3.4 in NaOH extracts. FA had a similar potential to complex with copper and zinc, so that the ratio of FA-Cu to FA-Zn was close to 1. In Na4P2O7-NaOH extracts, HA or FA had a similar potential to complex with copper and zinc. The ratio of HS-Cu to HS-Zn was close to 1. With manure composting, Na4P2O7-NaOH extractable HS-Zn increased to a level as high as HS-Cu. This indicated that more and more stable complexes of HS-Zn were formed in the late decomposition period. The competition between copper and zinc to be complexed with humic substance became weaker and weaker with the decomposition process.

关键词： manure copper and zinc decomposition process humic substance sequential extraction

Effect of Abiotic Factors on the Mercury Reduction Process by humic Acids in Aqueous Systems

在线全文

学校读者我要写书评

暂无评论

Pedosphere 2014年第1期24卷 125-136页

作者： JIANG Tao WEI Shi-Qiang D.C.FLANAGAN LI Meng-Jie LI Xue-Mei WANG Qiang LUO Chang College of Resources and Environment Department of Environment Science and EngineeringSouthwest University Chongqing Key Laboratory of Agricultural Resources and Environment USDA-Agricultural Research Service National Soil Erosion Research Laboratory

As a global pollutant process, the reduction of mercury （Hg） is especially important. One pathway is through an abiotic reduction with humic acids （HAs）, which is controlled by different factors, including initial Hg and HA concentrations, pH, temperature and light. In this study, three humic acids were selected to illustrate the Hg2＋ abiotic reduction mechanisms by HAs, and to identify the key limiting factors for reduction rates and amounts. In addition, the initial status of the HAs as a solid or in an aqueous solution were also compared, to help explain why HAs show different dominant characteristics （e.g. complexation or reduction） in the reaction process with Hg. Results indicated that HAs were able to reduce Hg abiotically. Higher initial Hg, higher HA concentrations and either high （8.1） or low （3.6） solution pH decreased the HA reduction capacity. In addition, Hg~ production rates increased with increasing temperature, and the same trend was observed with light exposure. humic acids added as an aqueous solution resulted in significantly greater HgO production than addition as a bulk solid. Finally, the Hg reduction rate and capacity varied significantly （P 〈 0.05） with HAs from different sources. These findings helped to explain why HAs showed different dominant characteristics （e.g. complexation or reduction） in the reaction process with of Hg2＋ reduction, which indicated that humic substances in sink or a source for Hg. Hg, and evidentially demonstrated the existence of a possible pathway natural environments, especially in water bodies, could act either as a

关键词： abiotic reduction complexation humic substance natural organic matter

Persistent free radicals in humin under redox conditions and their impact in transforming polycyclic aromatic hydrocarbons

在线全文

学校读者我要写书评

暂无评论

Frontiers of Environmental Science & Engineering 2020年第4期14卷 213-223页

作者： Hanzhong Jia Yafang Shi Xiaofeng Nie Song Zhao Tiecheng Wang Virender K.Sharma College of Resources and Environment Northwest A&F UniversityYangling 712100China State Key Laboratory of Soil Erosion and Dryland Farming on Loess Plateau Institute of Soil and Water ConservationNorthwest A&F UniversityYangling 712100China Program for the Environment and Sustainability Department of Occupational and Environmental HealthSchool of Public HealthTexas A&M UniversityCollege StationTX 77843USA

The role of humic substance-associated persistent free radicals(PFRs)in the fate of organic contaminants under various redox conditions remains *** study examined the characterization of original metal-free peat humin(HM),and HM treated with varying concentrations of H2O2 and L-ascorbic acid(VC)(assigned as H2O2-HM and VC-HM).The concentration of PFRs in HM increased with the addition of VC/H2O2 at concentrations less than 0.08 mol/*** evolution of PFRs in HM under different environmental conditions(e.g.,oxic/anoxic and humidity)was *** types of PFRs were detected in HM:a relatively stable radical existed in the original sample,and the other type,which was generated by redox treatments,wa s relatively *** spin densities of VC/H2O2-HM readily returned to the original value under relatively high humidity and oxic *** this process,the HM-associated"unstable"free radicals released an electron to O2,inducing the formation of reactive oxygen species(ROS,i.e.,·OH and·O2-).Th e generated ROS promoted the degradation of polycyclic aromatic hydrocarbons based on the radical quenching *** transformation rates followed the order naphthalene>phenanthrene>anthracene>benzo[a]*** results provide valuable insight into the HM-induced transformation of organic contaminants under natural conditions.

关键词： humic substance Polycyclic aromatic hydrocarbons(PAHs) Persistent free radicals(PFRs) Redox Reactive oxygen species(ROS)

Throughfall and stemflow chemical dynamics of Satoyama, a traditional secondary forest system under threat in Japan

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Forestry Research 2022年第3期33卷 813-826页

作者： Satoshi Asaoka Fuyuhiko Sumikawa Yoshifumi Watanabe Waqar Azeem Jadoon Masaki Ohno Nobumichi Shutoh Yuki Wakamatsu Lawrence M.Liao Akane Kanazawa Yuka Sato Natsumi Fujiwara Graduate School of Integrated Sciences for Life Hiroshima University1-4-4 KagamiyamaHigashi-Hiroshima739-8528Japan Research Center for Inland Seas Kobe University5-1-1 FukaeminamiHigashinadaKobe658-0022Japan Naragakuen Senior High School 430 YamadaYamatokoriyamaNara639-1093Japan Department of Environmental Sciences Faculty of Natural and Computational SciencesHazara UniversityDhodiaMansehra21130Khyber PakhtunkhwaPakistan Niigata University of Pharmacy and Applied Life Sciences 265-1 HigashijimaAkihaNiigata956-8603Japan Faculty of Science and Engineering Kindai University3-4-1 KowakaeHigashi-OsakaOsaka577-8502Japan Department of Maritime Science and Technology Japan Coast Guard Academy5 WakabaKureHiroshima737-8512Japan

The term 'Satoyama' refers to traditional and unique secondary forests in Japan that occupy intermediate zones between villages ('sato') and hills or mountains ('yama'). Satoyama landscapes help sustain ecosystem services and the diversity of secondary natural environments. As Japan relies more heavily on foreign timber imports, the traditional role of Satoyama in providing forest products has diminished, and this has led to their abandonment and poor management. The chemical behavior of cations, anions, and dissolved organic matter in throughfall and stemflow from one such threatened Satoyama system in central Japan was investigated. From autumn to winter, the atmospheric deposition of sulfates and nitrates was 2.5–6.0 times higher compared to the amounts in summer due to the intrusion of air masses from the Asian continent. The dissolved organic matter in the throughfall and stemflow was composed mainly of humic substances and protein derivatives. The deposition fluxes of dissolved organic carbon from throughfall (7.31–10.1 g m^(−2) a^(−1)) and stemflow (1.79–3.84 g m^(−2) a^(−1)) in this study were within ranges seen in temperate forests in previous studies. The deposition flux of sulfates was low compared to that in other forest types because canopy interaction was lower, suggesting higher canopy openness than in primary forests. If a shift from a mixed species Satoyama forest to a conifer-dominated forest occurs after the mass mortality of oak, the deposition flux of dissolved organic carbon and K^(+) might decrease by 33% and 62%, respectively, while NO_(3)^(−) might increase by 20%. In the near future, the degradation of Satoyama landscapes might change the levels of dissolved organic carbon and nitrogen loads, resulting in imbalances in river-ocean linkages affecting forested catchments and aquatic ecosystems in Japan.

关键词： Atmospheric deposition Dissolved organic matter humic substance Mass mortality Oak trees Sustainable development goals

Soil organic carbon stock and fractional distribution across central-south China

在线全文

学校读者我要写书评

暂无评论

International Soil and Water Conservation Research 2021年第4期9卷 620-630页

作者： Rubing Zeng Yujie Wei Jianjia Huang Xin Chen Chongfa Cai Key Laboratory of Arable Land Conservation(Middle and Lower Reaches of Yangtze River)of the Ministry of Agriculture College of Resources and EnvironmentHuazhong Agricultural UniversityWuhan430070China

The stock and stability of soil organic carbon(SOC)are critical to soil functions and global carbon cycle,but little quantitative information is available on the precise location and chemical components of SOC for soils across a wide range of climatic ***,a broad range of zonal soils were collected in forest land at topsoil(0-15 cm)and subsoil(15-30 cm)from temperate to tropical climatic gradient in central to south *** stock and stability of SOC were determined in terms of aggregate and humic *** in bulk soils with a less significant geographic variation was comparably higher at Haplic Luvisoils in temperate regions(3637.61 g m^(−2))and Rhodi-humic Ferrosols in tropical regions(3446.12 g m^(−2))than in the other experimental soils,but a consistent decreasing trend was observed along the soil profiles with the SOC stock was 1.11-1.97 times higher in the topsoil than in the *** addition,insoluble humin residue(HMr)as the dominant components of SOC ranged from 643.95 to 2696.90 g m^(−2) and decreased from temperate to tropical regions,which was consistent with the zonal variation of humic acids(HAs),but contrary to the zonal variation of fulvic acids(FAs)that fluctuated in a range of 39.67-389.55 g m^(−2) across the experimental *** to the results of partial correlation analysis,the variation of FAs stock was significantly attributed to soil pH,bulk density,iron and aluminum oxides,clay,and clay mineral content(|r|>0.61,p<0.05),while these soil physical properties showed a contradictory effects on HAs,iron-linked humin(HMi),clay-combined humin(HMc),and ***,the aggregate-associated carbon stock was mainly stored in macroaggregates(36.34-76.09%)for both SOC and its chemical components,especially in topsoils,and its zonal variation was associated with that of bulk *** general,the redundancy analysis(RDA)revealed that mean annual precipitation(MAP)accounted for 81.8%and 13.8%of the variance in SOC chemical a

关键词： Carbon stock humic substance Soil aggregation

Fertigation with Wastewater and Vermicompost: Soil Biochemical and Agronomic Implications

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Pedosphere 2014年第5期24卷 625-634页

作者： G.MASCIANDARO E.PERUZZI S.DONI C.MACCI Consiglio Nazionale delle Ricerche (CNR) Istituto per lo Studio degli Ecosistemi (ISE) Via Moruzzi 1 Pisa 56124 (Italy)

To study how wastewater(WW) and different organic sources(humic substances or vermicompost) affected soil chemical and biochemical fertility and agronomic productivity in field-grown melon, an experiment arranged in a randomized complete block design with three replications was conducted with the following treatments: three different mixtures of irrigation water(100% WW, 50% WW with 50% groundwater, and 100% groundwater) and, for each WW treatment, four different organic fertilization treatments of control without organic matter application(CK), vermicompost used as surface mulch(SM), vermicompost incorporated into the soil(VC),and humic substances extracted by vermicompost(HS). Chemical and biochemical results indicated an improvement in soil fertility,suggested by the increase in soil organic carbon and nutrient(nitrate and macro- and microelements) contents and in soil microbial activities(hydrolytic and oxidative enzymes), in particular in the VC treatments. In addition, even soil potential metabolism was stimulated by WW combined with organic treatments, as highlighted by the increase in the metabolic(dehydrogenase activity/watersoluble carbon) and nitrification indices(NO-3and NH+4). Melon productivity confirmed these results, with the highest yield and melon quality in the VC treatments irrigated with 100% WW. In conclusion, the combined use of WW and organic amendment,recovering both mineral and organic nutrients from these kinds of recycled materials, was effective in the improvement of soil quality and crop productivity.

关键词： Cucumis melo enzyme activity humic substance organic matter soil quality

Fractionation of Zn,Cd and Pb in a Tropical Soil After Nine-Year Sewage Sludge Applications

在线全文

学校读者我要写书评

暂无评论

Pedosphere 2010年第5期20卷 545-556页

作者： T.A.R.NOGUEIRA W.J.MELO I.M.FONSECA S.A.MARCUSSI G.M.P.MELO M.O.MARQUES Department of Plant Nutrition Center for Nuclear Energy in AgricultureUniversity of Sao Paulo Department of Technology Sao Paulo State University

A long-term field experiment was carried out in the experiment farm of the Sao Paulo State University,Brazil,to evaluate the phytoavailability of Zn,Cd and Pb in a Typic Eutrorthox soil treated with sewage sludge for nine consecutive years,using the sequential extraction and organic matter fractionation *** 2005-2006,maize(Zea mays L.) was used as test plants and the experimental design was in randomized complete blocks with four treatments and five *** treatments consisted of four sewage sludge rates(in a dry basis):0.0(control,with mineral fertilization),45.0,90.0 and 127.5 t ha-1,annually for nine *** maize sowing,the sewage sludge was manually applied to the soil and incorporated at 10 cm *** samples(0-20 cm layer) for Zn,Cd and Pb analysis were collected 60 days after *** successive applications of sewage sludge to the soil did not affect heavy metal(Cd and Pb) fractions in the soil,with exception of Zn *** Zn,Cd and Pb distributions in the soil were strongly associated with humin and residual fractions,which are characterized by stable chemical ***,Cd and Pb in the soil showed low phytoavailability after nine-year successive applications of sewage sludge to the soil.

关键词： heavy metals humic substance sequential extraction Zea mays L.