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Speciation and bioaccessibility of lead and cadmium in soil treated with metal-enriched Indian mustard leaves

Journal of environmental Sciences 2011年第4期23卷 624-632页

作者： Yanshan Cui Jin Fu Xiaochen Chen college of resources and environment Graduate University of Chinese Academy of Sciences Beijing 100049 China.

Indian mustard （Brassica juncea （L.） Czern.） has shown good potential for the phytoremediation of soil contaminated with heavy metals. However, there is little information about the speciation and bioaccessibility of heavy metals in soil during the decomposition of metal-rich Indian mustard leaves. Incubation experiments （1-, 3-, and 6-month） were carried out in Beijing and Hunan soil with metal-rich Indian mustard leaves addition （1% and 3%） and the effects of mustard leaves addition on the speciation and bioaccessibility of heavy metals were studied. The results showed that the addition of mustard leaves led to significant increases in pH and DOC in the Hunan soil. Both 1% and 3% of mustard leaf amendment caused the percentage of the exchangeable （F1）, precipitated with carbonates （F2）, bound to Fe/Mn oxides （F3） and bound to organic matter （F4） fractions of Pb and Cd to increase dramatically, while the percentage of the residual fraction （F5） of Cd and Pb significantly dropped in both Beijing and Hunan soils. Mustard leaf addition caused the bioaccessibility of Pb to decrease in the gastric phase, whereas the values increased in the small intestinal phase. The Cd bioaccessibility increased with mustard leaf addition in both the gastric and small intestinal phases. In conclusion, the metal-enriched mustard leaves addition induces Pb and Cd concentrations and their mobility increasing in the Beijing and Hunan soils. Therefore, heavy metal risk in metal-enriched plant leaves should be considered in phytoremediation system in which heavy metal might be brought back to soil and changed over time.

关键词： lead cadmium speciation bioaccessibility decomposition

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Roles of manganese oxides in degradation of phenol under UV-Vis irradiation:Adsorption,oxidation,and photocatalysis

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Journal of environmental Sciences 2011年第11期23卷 1904-1910页

作者： Qin Zhang Xiaodi Cheng Chen Zheng Xionghan Feng Guohong Qiu Wenfeng Tan Fan Liu Key Laboratory of Subtropical Agriculture and environment Ministry of Agriculture College of Resources ＆ Environment Huazhong Agricultural University Wuhan 430070 China college of Land Resource and environment Jiangxi Agricultural University Nanchang 330045 China

Manganese oxides are known as one type of semiconductors,but their photocatalysis characteristics have not been deeply *** this study,photocatalytic degradation of phenol using several synthesized manganese oxides,i.e,acidic birnessite （BIR-H）,alkaline birnessite （BIR-OH）,cryptomelane （CRY） and todorokite （TOD）,were comparatively *** elucidate phenol degradation mechanisms,X-ray diffraction （XRD）,ICP-AES （inductively coupled plasma-atomic emission spectroscopy）,TEM （transmission electronic microscope）,N 2 physisorption at 77 K and UV-visible diffuse reflectance spectroscopy （UV-Vis DRS） were employed to characterize the structural,compositional,morphological,specific surface area and optical absorption properties of the manganese *** 12 hr of UV-Vis irradiation,the total organic carbon （TOC） removal rate reached 62.1%,43.1%,25.4%,and 22.5% for cryptomelane,acidic birnessite,todorokite and alkaline birnessite,*** to the reactions in the dark condition,UV- Vis exposure improved the TOC removal rates by 55.8%,31.9%,23.4% and 17.9%.This suggests a weak ability of manganese oxides to degrade phenol in the dark condition,while UV-Vis light irradiation could significantly enhance phenol *** manganese minerals exhibited photocatalytic activities in the order of：CRY BIR-H TOD *** may be three possible mechanisms for photochemical degradation：（1） direct photolysis of phenol;（2） direct oxidation of phenol by manganese oxides;（3） photocatalytic oxidation of phenol by manganese *** oxidation of phenol appeared to be the dominant mechanism.

关键词： manganese oxides adsorption oxidation photocatalysis degradation phenol

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Cellulose Functionalization via ATRP Grafting of Glycidyl Methacrylate for Cr（VI） Adsorption

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Chinese Journal of Chemistry 2013年第12期31卷 1551-1556页

作者： Chunxiang Lin Sha Qiao Danhui Liu Minghua Liu college of environment & resources Fuzhou University Fuzhou Fuj ian 350108 China

Cellulose was first grafted with glycidyl methacrylate （GMA） in an ionic liquid via atom transfer radical polymerization （ATRP） and then the introduced epoxy groups were reacted with ethanediamine （EDA） to obtain an amino adsorbent. The grafting copolymer and the obtained adsorbent were characterized by FTIR, aH NMR, TEM and SEM. The results showed that the grafted copolymers had grafted polymer chains with well-controlled molecu- lar weight and polydispersity, the polymerization was a controlled system. The cellulose adsorbent had numerous micropores on the surface and showed high performance for Cr（VI） adsorption. The adsorption behavior was pH dependent and the sorption equilibrium was achieved within 2 h on the adsorbent.

关键词： cellulose functionalization atom transfer radical polymerization (ATRP) ionic liquid sorption Cr(VI)

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Phosphorus Loss from Dry Sloping Lands of Three Gorges Reservoir Area, China

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Pedosphere 2013年第3期23卷 385-394页

作者： HU Zheng-Feng GAO Ming XIE De-Ti WANG Zi-Fang college of resources & environment Southwest University Chongqing Municipal environmental Protection Bureau

Eutrophication in the Three Gorges Reservoir has become a serious issue, and phosphorus (P) is the nutrient thought to be primarily responsible although there are few studies about P loss from the mostly sloping farmlands of the area. This work investigated the amounts and forms of P loss from 9 farmlands with the slopes of 4°, 9°, and 17° in a small watershed, Wangjiagou in Fuling District, Chongqing of China. The slope of the relationship between runoff and rainfall increased with field slope; i.e., there was a significant interaction between the effects of rainfall and field slope on water export. For sediment export by surface runoff, there was no interaction between field slope and rainfall, and the intercept of the relationship between rainfall and sediment loss was significantly different for the 3 slopes. The main P loss was from sediments, regardless of slope. In the runoff water, particulate P was the largest P fraction, and its loss was greatest from the steepest land and least from the flattest. The release of total P and available P from sediments followed the same trend. The P loss during May to July in Wangjiagou was more than 60% of the annual total.

关键词： agricultural production area erosion nutrient loss purple soil soil loss

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Synthesis of 2,5-diformylfuran from renewable carbohydrates and its applications: A review

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Green Energy & environment 2021年第1期6卷 22-32页

作者： Jinhang Dai college of environment and resources Chongqing Technology and Business UniversityChongqing400067China

The synthesis of fine chemicals and fuel candidates from renewable biomass-based feedstocks has attracted much attention due to declining fossil *** value-added furan derivatives,such as 5-hydroxymethylfurfural(HMF),2,5-diformyfuran(DFF)and 2,5-furandicarboxylic acid,have been successfully produced from *** these,DFF,the aerobic oxidation product of HMF,is a key chemical and can be used in organic synthesis and functional polymer *** this review,different catalytic systems for the synthesis of DFF from monosaccharide,disaccharide and polysaccharide were summarized,while reaction pathways and catalyst stability were also ***,the applications of DFF were introduced in ***,prospects of more effective methods to DFF production and application were discussed.

关键词： 2,5-Diformyfuran Oxidation HMF Carbohydrate Biomass

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Theoretical Study on the Structures and Properties of Phenobarbital Imprinted Polymers

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Chinese Journal of Structural Chemistry 2014年第10期33卷 1421-1430页

作者：苏婷婷刘俊渤唐珊珊常海波靳瑞发 college of resources and environment Jilin Agricultural University Department of Chemistry Chifeng University

Recently, the investigation of novel molecularly imprinted polymers（MIPs） has attracted a lot of interest and becomes a fascinating field. The phenobarbital（PHN） was taken as an imprinted molecule and the 2-vinyl-4,6-diamino-1,3,5-triazine（VDAT） was considered as a functional monomer in this study. The geometry optimization, natural bond orbital（NBO） charge, and molecular electrostatic potential（MEP） of PHN and VDAT were studied at the M062 X level belonging to one of the hybrid density functional theories. Furthermore, we discussed the bonding conditions of PHN molecular imprinted polymers（PHN-MIPs） via the hydrogen bond length and atoms in molecules（AIM） theory. The rebinding property of PHN-MIPs was also researched. The results of MEP and NBO charge analysis were coincident. The stability property was excellent when the ratio of PHN and VDAT was 1：4. Except the classic hydrogen bonds, non-classical hydrogen bonds also existed in the imprinted polymers. By simulating the rebinding energies between the pentobarbital（PNT）, barbital（BAR）, and PHN-MIPs after the elution of PHN, the rebinding property of PHN-MIPs to PHN was excellent when PNT and BAR existed all at once. This research can provide theoretical reference for the synthesis and characterization of novel PHN-MIPs.

关键词： phenobarbital 2-vinyl-4 6-diamino-1 3 5-triazine molecular imprinting computer simulation hydrogen bonds

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Several Rules for Treating Phenol Wastewater via Oxidation by O_3/UV-formed Radicals

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Chemical Research in Chinese Universities 2006年第1期22卷 25-28页

作者： LIU Miao JIAO Xin-qian WU Di DIAO Wei-li ZHANG Yu college of environment and resources Jilin University Changchun 130012 P. R China

The treatment of phenol wastewater with an ultraviolet source and an oxone generator by introducing salicylic acid as the capturer is described. The presence of HO during the phenol degradation has been proved. The impacts of factors such as acidity and reaction time on the HO formation are also discussed. The results demonstrate that HO ＇ generated from ozone/UV oxidation under a basic condition is the immediate cause of phenol degradation. At room temperature and a pH value of 9. 93, the degradation of phenol occurs rapidly within 0. 5 rain and the removal of phe- nol（ 100 mg/L） is above 98. 5% within 15 min; in the meantime, the pH value declines gradually with the degradation of phenol. A discussion about the formation and the transformation of the intermediate products during phenol degradation is included.

关键词： Ozone UV oxidation Radical Phenol wastewater Degradation

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Organophosphate esters in water,suspended particulate matter(SPM)and sediments of the Minjiang River,China

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Chinese Chemical Letters 2021年第9期32卷 2812-2818页

作者： Hongling Yin Qin Liu Xu Deng Xiaowen Liu Shuhong Fang Yuanming Xiong Jiaojiao Song college of resources and environment Chengdu University of Information TechnologyChengdu 610025China

As organic pollutants of emerging concern,organophosphate esters(OPEs)have shown toxicity to organisms after entering the water ***,research on OPEs in freshwater in Southwest China is very *** levels,distribution and partitioning behavior of OPEs in the Minjiang River and their influencing factors is still *** this study,six OPEs,tri-n-butyl phosphate(Tn BP),tri(2-chloroethyl)-phosphate(TCEP),trichloropropyl phosphate(TCPP),triphenyl phosphate(TPh P),tributoxyethyl phosphate(TBEP),and tris(2-ethylhexyl)-phosphate(TEHP),were determined in surface water,suspended particle matter(SPM)and sediments of the Minjiang *** results showed that the average concentrations of∑_(6)OPEs in surface water,SPM and sediments of the Minjiang River were 199.32±124.95 ng/L,38463.79±45641.89 ng/g dry weight(dw)and 76.45±28.00 ng/g dw,*** concentrations of OPEs were detected in SPM samples,indicating that more attention should be paid to pollution in *** is worth noting that the variation trend of OPEs in SPM was almost opposite to that in water but basically similar to that in *** proportions of alkyl OPEs in∑_(6)OPEs increased from surface water to SPM and *** OPEs were the main pollutants in SPM(10.44%–80.88%of∑_(6)OPEs,mean of 54.52%)and sediments(59.08%–81.30%of∑_(6)OPEs,mean of 68.91%),whereas chlorinated OPEs were the most abundant components in surface water(43.16%–75.99%ofδ∑_(6)OPEs,mean of 55.50%).The water-sediment partition coefficient(logKOC)of OPEs was 4.97–7.58,while the water-SPM partition coefficient was 6.71–*** significant correlations were found between log KOW and *** was not the main factor affecting the distribution of OPEs in the Minjiang River,China.

关键词： Organophosphate esters Suspended particulate matter Partition coefficient The Minjiang River

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Effect on greenhouse gas balance of converting rice paddies to vegetable production

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Acta Geochimica 2017年第3期36卷 353-354页

作者： Lei Wu Xian Wu Ronggui Hu college of resources and environment Huazhong Agricultural University Wuhan 430070 China

Rice paddies are increasingly being converted to vegetable production due to economic benefits related,in part,to changes in demand during recent ***,we implemented a parallel field experiment to simultaneously measure annual emissions of CH_4and N_2O,and soil organic carbon(SOC)stock changes,in rice paddies(RP),rice paddy–converted conventional vegetable fields(CV),and rice paddy–converted greenhouse vegetable fields(GV).Changing from rice to vegetable production reduced CH_4emissions by nearly 100%,and also triggered substantial N_2O ***,annual N_2O emissions from GV significantly exceeded those from CV due to lower soil p H and higher soil *** SOC losses occurred after one year of cultivation of RP,CV,and GV,contributing an important share(3.4%,32.2%,and 10.3%,respectively)of the overall global warming potential(GWP)*** decline in CH_4emissions outweighed the increased N_2O emissions and SOC losses in CV and GV,leading to a 13%–30%reduction in annual GWP as compared to *** results suggest that large-scale expansion of vegetable production at the expense of rice paddies is beneficial for mitigating climate change in terms of the overall GWP.

关键词： Greenhouse gas balance Land management change CH4 N2O Soil organic carbon

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Optimizing the key parameter to accelerate the recovery of AMOC under a rapid increase of greenhouse gas forcing

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Atmospheric and Oceanic Science Letters 2025年第1期18卷 39-45页

作者： Haolan Ren Fei Zheng Tingwei Cao Qiang Wang International Center for Climate and environment Science(ICCES) Institute of Atmospheric PhysicsChinese Academy of SciencesBeijingChina University of Chinese Academy of Sciences BeijingChina college of Oceanography Hohai UniversityNanjingChina CAS Key Laboratory of Ocean Circulation and Waves Institute of OceanologyChinese Academy of Sciences and Pilot National Laboratory for Marine Science and Technology(Qingdao)QingdaoChina

Atlantic Meridional Overturning Circulation(AMOC)plays a central role in long-term climate variations through its heat and freshwater transports,which can collapse under a rapid increase of greenhouse gas forcing in climate *** studies have suggested that the deviation of model parameters is one of the major factors in inducing inaccurate AMOC *** this work,with a low-resolution earth system model,the authors try to explore whether a reasonable adjustment of the key model parameter can help to re-establish the AMOC after its *** a new optimization strategy,the extra freshwater flux(FWF)parameter is determined to be the dominant one affecting the AMOC’s *** traditional ensemble optimal interpolation(EnOI)data assimilation and new machine learning methods are adopted to optimize the FWF parameter in an abrupt 4×CO_(2) forcing experiment to improve the adaptability of model parameters and accelerate the recovery of *** results show that,under an abrupt 4×CO_(2) forcing in millennial simulations,the AMOC will first collapse and then re-establish by the default FWF parameter ***,during the parameter adjustment process,the saltier and colder sea water over the North Atlantic region are the dominant factors in usefully improving the adaptability of the FWF parameter and accelerating the recovery of AMOC,according to their physical relationship with FWF on the interdecadal timescale.

关键词： Recovery of AMOC 4×CO_(2)forcing Key parameter Parameter estimation Data assimilation Machine learning

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