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NMR studies of stock process water and reaction pathways in hydrothermal carbonization of furfural residue

Green Energy & Environment 2018年第2期3卷 163-171页

作者： Fen Yue Christian Marcus Pedersen Xiuyin Yan Yequn Liu Danlei Xiang Caifang Ning Yingxiong Wang Yan Qiao Institute of Coal Chemistry Chinese Academy of Sciences Institute of Process Engineering Chinese Academy of Sciences Department of Chemistry University of Copenhagen taiyuan supervision and testing station for quality of grain Department of Applied Biology and Chemical Technology The Hong Kong Polytechnic University

Hydrothermal carbonization(HTC) is a valuable approach to convert furfural residue(FR) into carbon material. The prepared biochars are usually characterized comprehensively, while the stock process water still remains to be studied in detail. Herein, a NMR study of the main components in stock process water generated at different HTC reaction conditions was reported. Various qualitative and quantitative NMR techniques(~1H and ^(13)C NMR,~1H-~1H COSY and ~1H-^(13)C HSQC etc.) especially 1D selective gradient total correlation spectroscopy(TOCSY NMR) were strategically applied in the analysis of HTC stock process water. Without separation and purification, it was demonstrated that the main detectable compounds are 5-hydroxymethylfurfural, formic acid, methanol, acetic acid, levulinic acid, glycerol, hydroxyacetone and acetaldehyde in this complicate mixture. Furthermore, the relationship between the concentration of major products and the reaction conditions(180-240 ℃ at 8 h, and 1-24 h at 240 ℃) was established. Finally, reasonable reaction pathways for hydrothermal conversion of FR were proposed based on this result and our previously obtained characteristics of biochars. The routine and challenging NMR methods utilized here would be an alternative other than HPLC or GC for biomass conversion research and can be extended to more studies.

关键词： NMR Hydrothermal carbonization Furfural residue Stock process water

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Screening Rice Germplasm with Different Genetic Backgrounds for Cadmium Accumulation in Brown Rice in Cadmium-Polluted Soils

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Rice science 2023年第4期30卷 267-270页

作者： ZHANG Weixing GUAN Meiyan WANG Jie WANG Yulei ZHANG Weigui LU Xinzhe XU Ping CHEN Mingxue ZHU Youwei Rice Product quality supervision and Inspection Center China National Rice Research InstituteHangzhou 310006China Zhejiang Main station of Cultivated Land quality and Fertilizer Management Agricultural and Rural Bureau of Zhejiang ProvinceHangzhou 310020China Zhejiang Institute of Geological Survey Hangzhou 311200China

To screen rice germplasm with different genetic backgrounds for cadmium(Cd)accumulation in brown rice from common cultivated rice,we monitored grain Cd concentrations and characterized their patterns of 54 main varieties planted at two sites[Fuyang(FY)and Changshan(CS)in Zhejiang Province,China]with both low and high Cd-polluted *** found most varieties got higher Cd levels than 0.2 mg/kg in the Cd-polluted soil with the normal agronomic management,which suggested high risk of Cd exposure from the two *** Cd accumulation pattern was found in hybrid rice,but it differed between ***,varieties with the same female or male parent may have different Cd accumulation capacities,meaning that the environment factors should be considered to screen low-Cd-accumulation varieties.

关键词： planted soil cultivated

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Utilization of Blast Furnace Slag, Steel Slag in the Production of Clinker

Utilization of Blast Furnace Slag, Steel Slag in the Product...

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中国材料大会2012

作者： Shouwan Qin Jianjun Shen Huifen Wang Zhaoran Xiao Henan University of Technology Construction Project quality supervision station of Zhengzhou City

ISBN: (纸本)9783037856062;3037856068

The study on the use of blast furnace slag, steel slag and fly ash as raw materials to produce cement clinker has been carried out in the present investigation. The burnability of raw meal was determined by the linear shrinkage and free lime content of clinkers sintered at different temperatures. The microstructrue and properties of raw meal and clinker were investigated by the means of chemical analysis, X-ray diffraction and petrographic analysis. The physical and mechanical performance of cement was tested according to the standards. The results showed that the burnability was good as the free lime content was lower than 0.5w% in the clinker sintered at 1350℃. It is believed that the nucleation of alite only needs to grow bigger and rearrange with the rising temperature. The micrograph of clinker sintered at 1450℃ showed that there were some garlands of belite crystals around alite crystals because of high temperature or the local reducing atmosphere caused by the compact raw meal. High-quality cement clinker with compressive strength of 60.4MPa was produced by utilizing limestone, blast furnace slag, steel slag and fly ash as raw materials after curing 28 days.

关键词： Clinker Blast furnace slag Steel slag Burnablity Performance.

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Dating recent sediments from the subaqueous Yangtze Delta and adjacent continental shelf,China

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Journal of Palaeogeography 2014年第2期3卷 207-218页

作者： Zhang-Hua Wang Yong-Hong Dong Jing Chen Xiao-Feng Li Juan Cao Zhi-Yong Deng State Key Laboratory of Estuarine and Coastal Research East China Normal University Department of Geography East China Normal University Shanghai Radiation Environmental supervision station

In this study we analyzed sediment lithology,fallout of 210Pb and 137Cs,and spheroidal carbonaceous particles(SCPs) for two short cores,YZE and CX38,obtained by gravity corer from the Yangtze River mouth offshore and adjacent continental shelf,to compare geochronological methods on the recent sediments of this *** and grain size changes in YZE suggested the re-discharging of the North Channel of the Yangtze River mouth by flood events during 1949-1954 and associated accretion in the offshore *** event was validated by a remarkable zone of declination in both 137Cs and 210Pb activities and the absolute ages derived from the 137Cs and *** contrast,210Pb results show obvious disturbance of grain size by sediment mixing and cannot be interpreted above 100 *** CX38,absolute ages for the early-and mid-1950s were derived by the 137Cs and the SCP profile respectively,which occurred in a reasonable *** excess 210Pb distribution shows exponentially decreasing activities with depth,and the mean sedimentation rate agrees roughly with the one inferred from the SCP *** suggest that the limitation of the 210Pb method needs consideration while the SCP profile has the potential to provide a useful and independent dating method for recent Yangtze offshore and adjacent shelf sediments.

关键词： geochronology lithology change 137Cs and 210Pb SCP profile Yangtze offshore

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Yield sustainability of winter wheat under three limited-irrigation schemes based on a 28-year field experiment

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The Crop Journal 2022年第6期10卷 1774-1783页

作者： Yanmei Gao Meng Zhang Zhimin Wang Yinghua Zhang College of Agronomy and Biotechnology China Agricultural UniversityBeijing 100193China School of Life Science Shanxi Normal UniversityTaiyuan 030031ShanxiChina Ministerial and Provincial Co-Innovation Centre for Endemic Crops Production with High-quality and Efficiency in Loess Plateau Shanxi Agricultural UniversityTaigu 030801ShanxiChina

Sustainable intensification is an agricultural development direction ***,little is known about the yield sustainability of winter wheat(Triticum aestivum L.)under limited irrigation schemes on the North China Plain(NCP).A 28-year field experiment from 1991 to 2018 at Wuqiao Experimental station was used to characterize long-term yield,evapotranspiration(ET),and water use efficiency(WUE)trends under three irrigation treatments(W1,irrigation just before sowing;W2,irrigation before sowing and at jointing stage;W3,irrigation before sowing,at jointing stage,and at anthesis).Yield gaps and the effects of genetic improvement,climate change,and climate variables on wheat yield and key phenological stages were estimated using the Agricultural Production Systems Simulator(APSIM)*** yield and WUE of winter wheat increased during the 28 years under the three irrigation treatments,and the upward trend of WUE followed a saturation curve *** increased *** results showed that genetic improvement dramatically prolonged the phenological stages of vegetative growth period and contributed to yield increase by 0.03%-15.6%.The rapid increase in yield with lower water use was associated mainly with an increase in biomass with genetic improvement and partly with an increase in harvest index.A curvilinear relationship between WUE and yield emphasized the importance of obtaining high yields for high *** yield gaps between potential yield and yield under W1 treatment increased from 1991 to 2018 but were relatively constant for the W2 and W3 *** atmospheric CO_(2) concentration offset the negative effects of temperature increase on yield,leading to minor(-2.3%to 0.3%)changes in yield under climate ***,genetic improvement played a dominant role in yield increase,and limited-irrigation schemes(W2 and W3)can increase wheat yield and promote sustainability of crop production on the NCP.

关键词： Yield Sustainability Cultivars Climate change Phenology

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Flow regime changes in three catchments with different landforms following ecological restoration in the Chinese Loess Plateau

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Journal of Arid Land 2020年第1期12卷 44-57页

作者： LUO Zhidong LIU Erjia QI Shi ZHAO Nan SUN Yun College of Soil and Water Conservation Beijing Forestry UniversityBeijing 100083China Water and Soil Conservation Monitoring Center of Ministry of Water Resources Beijing 100053China Key Laboratory of Soil and Water Conservation of State Forestry Administration Beijing 100083China Engineering Research Center of Forestry Ecological Engineering Ministry of EducationBeijing 100083China Shanxi Institute of Soil and Water Conservation Taiyuan 030045China

The Chinese Loess Plateau is known as one of the most severe soil erosion regions in the *** ecological restoration projects,i.e.,the integrated soil conservation project since the 1970s and the''grain for Green''project since 1999,have been progressively implemented to control the soil erosion in this *** restoration has greatly changed flow regime over the past five ***,the mechanism of how flow regime responds to ecological restoration among landforms remains poorly *** this study,we investigated the temporal dynamics of flow regime in three catchments,i.e.,Wuqi,Honghe and Huangling hydrological stations,respectively representing the loess hilly-gully,loess table-gully and rocky mountain(covered by secondary forest)areas in the Chinese Loess Plateau,using daily hydrological data during the 1960s–*** nonparametric Mann-Kendall test,Pettitt's test and daily flow series were used to investigate the changes of flow *** negative trends of annual streamflow were detected at the Wuqi and Honghe stations,except for the Huangling *** annual baseflow at the Wuqi station showed a significantly positive trend whereas a significantly negative trend was observed at the Honghe station,and there was no significant trend at the Huangling *** was interesting that baseflow index significantly increased during the whole period in all ***,the trends and change points of daily flow series derived by different percentages of exceedance and extreme series in different consecutive days varied among *** on the change points analysis of annual streamflow,we divided data series into three periods,i.e.,the baseline period(from 1959 and 1963 to 1979,PI),the integrated soil conservation period(1980–1999,PII)and the''grain for Green''period(2000–2011,PIII).We found that streamflow decreased due to the reduction of high streamflow(exceeding 5%of time within a year)and median streamflow(50%)

关键词： change point extreme series hydrological data soil erosion streamflow changes

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