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Effect of inoculation during different phases of agricultural waste composting on spectroscopic characteristics of humic acid

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Journal of Central South University 2015年第11期22卷 4177-4183页

作者：黄红丽曾光明罗琳张嘉超喻曼秦普丰 college of resources and Environment Hunan Agricultural University college of environmental Science and Engineering Hunan University Key Laboratory of environmental Biology and Pollution Control of Ministry of Education (Hunan University) environmental resources and Soil Fertilizer Institute Zhejiang Academy of Agricultural Sciences

The white-rot fungus, Phanerochaete chrysosporium(P. chrysosporium), was inoculated during different phases of agricultural waste composting and its effect on the spectroscopic characterization of humic acid(HA) was studied. Three runs were used in this study: Run A was the control without inoculating, and Runs B and C were inoculated P. chrysosporium during the first and the second fermentation phase, respectively. The elemental analysis, ultra-violet spectroscopy(UV), fluorescence spectra, Fourier transform infra-red(FTIR) and 13 C nuclear magnetic resonance(13C-NMR) of HA all lead to the same conclusion, that is, the degree of aromatization and polymerization of HA increases after 42 days composting. However, the inoculation during different phases presents different effects. P. chrysosporium increases the degree of aromatization and polymerization of HA when it is inoculated during the second fermentation phase, while it does not produce an obvious change on the humification degree of HA when it is inoculated during the first fermentation phase.

关键词： inoculation composting Phanerochaete chrysosporium

Spatial Distribution and Temporal Trend Characteristics of Agro-Climatic resources and Extreme Climate Events during the Soybean Growing Season in Northeast China from 1981 to 2017

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Journal of Meteorological Research 2020年第6期34卷 1309-1323页

作者： Shibo GUO Xiaoguang YANG Zhentao ZHANG Fangliang ZHANG Tao LIU college of resources and environmental Sciences China Agricultural UniversityBeijing 100193

Soybean is an important oil ***-climatic resources and extreme climate events during the growing season directly affect the crop growth and grain *** this study,we used historical climate data and phenology observation data to investigate the spatial distributions and temporal trends of agro-climatic resources and extreme climate events during the growing season for soybean in Northeast China(NEC).The results showed that during the soybean growing season,the thermal time increased while both the effective precipitation and photosynthetically active radiation(PAR)*** the growing season,the thermal time increased by 44.0°C day decade–1 during the vegetative stage but decreased by 16.5°C day decade–1 during the reproductive stage;the effective precipitation increased by 1.8 mm decade–1 during the vegetative stage but decreased by 7.3 mm decade–1 during the reproductive stage;PAR decreased by 6.5 and 11.9 MJ m–2 decade–1 during the vegetative and reproductive *** frequency of extreme cold days showed a decreasing trend during the four study phases of sowing to emergence,sowing–flowering,15 days before flowering–flowering,and pod to physiological *** the soybean growing season,the frequency of extreme heat days and the maximum number of consecutive dry days(CDD)increased,and the maximum number of consecutive wet days(CWD)and heavy precipitation days *** results of this study could be used in selecting optimal management in soybean production in order to take advantage of beneficial climatic elements.

关键词： soybean Northeast China(NEC) agro-climatic resources extreme climate events asymmetry

Spatiotemporal distribution and influencing factors of Ulva prolifera and Sargassum and their coexistence in the South Yellow Sea,China

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Journal of Oceanology and Limnology 2022年第3期40卷 1070-1084页

作者： Longxiao ZHENG Mengquan WU Min ZHOU Lianjie ZHAO college of resources and environmental Engineering Ludong UniversityYantai 264039China

Marine ecological disasters occurred frequently in recent years and raised widespread concerns about the ecological health of the *** analyzed the spatiotemporal distributions of Ulva prolifera and Sargassum from April to July each year between 2016 and 2020 in the South Yellow Sea using multisource(GF-1 and HJ-1A/1B)remote sensing images,combined with the MODIS sea surface temperature(SST)data,photosynthetically active radiation(PAR)data,and Quick SCAT sea surface wind(SSW)data,to explore the potential influencing *** results show that(1)*** and Sargassum appeared mainly from May to July and April to June,respectively;(2)*** showed an impact in larger spatial scope than that of *** originated in the shoal area of northern Jiangsu and finally disappeared in the sea near Haiyang-Rongcheng *** spatial scope of the impact of Sargassum tended to *** was first detected in the ocean northeast of the Changjiang(Yangtze)River estuary and disappeared near 35°N;and(3)correlation analysis showed that the SST influenced the growth rate of *** and *** had varied eff ects on *** and Sargassum at different times.A moderate light conditions could accelerate the growth and reproduction of *** and *** irradiance levels of ultraviolet radiation may cause photoinhibition and damage on *** and *** southeast monsoon and surface currents promoted the drift of *** and Sargassum from the southeast to the northwest and ***,the spatial and temporal similarities and differences between *** and Sargassum were influenced by a combination of factors during their growth processes.

关键词： Ulva prolifera Sargassum virtual-baseline floating macro algae height(VB-FAH) spatiotemporal distribution South Yellow Sea multi-source remote sensing

Simple construction of the α-MnO2@ZIF-8 nanomaterial with highly enhanced U(Ⅵ) adsorption performance and assessed removal mechanism

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Progress in Natural Science:Materials International 2023年第4期33卷 508-517页

作者： Siyi Wang Yuxuan Bai Zhixiong Zhang Chengde Xie Wenhui Song Chen Wang Zhuoyu Ji Jianjun Wang North China Electric Power University MOE Key Laboratory of resources and environmental Systems Optimization college of environmental Science and Engineering

In this study, the one-dimensional nanomaterial α-MnO2@ZIF-8 was satisfactorily fabricated using a simple hydrothermal method by modifying ZIF-8 on α-MnO2nanowires for high-performance extraction of U(Ⅵ) out of water solution. The experimental data indicated that the adsorption of U(Ⅵ) on α-MnO2@ZIF-8 was intensely dependent on solution pH but not on ionic strength. The maximum adsorption of U(Ⅵ) on α-MnO2@ZIF-8 at pH= 5.0 and T = 298 K was 802.36 mg/g, substantially higher than the adsorption on α-MnO2(22.32 mg/g) or ZIF-8(551.31 mg/g) under the same conditions, indicating that the performance of the modified α-MnO2was greatly enhanced. Attaining adsorption equilibrium within 45 min, the analytical kinetic process of α-MnO2@ZIF-8 indicated that its adsorption on U(Ⅵ) was monolayer chemisorption. The adsorption experiments and XPS analyzed the possible adsorption mechanism of U(Ⅵ) in the reaction with α-MnO2@ZIF-8 during the adsorption process, namely intra-sphere surface complexation, chemisorption and electrostatic interaction. The simple preparation and high removal efficiency of α-MnO2@ZIF-8 indicated that this adsorbent had good prospects for application in wastewater.

关键词： α-MnO_2@ZIF-8 Adsorption Uranium Mechanism

Phosphorus accumulation and eutrophication in feed-supply freshwater fishponds

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Journal of environmental Sciences 2006年第4期18卷 816-821页

作者： ZHANG Ming-kui FANG Li-ping Institute of Soil and Water resources and environmental Science College of Natural Resource and Environmental Sciences Zhejiang UniversityHangzhou 310029 China

The rapid growth and intensification of freshwater fishery can cause imbalances between phosphorus （P） input in feed and its output in produce. This aquaculture can result in enriching exogenous P in fishponds and, consequently, accelerates the process of eutrophication. To assess relations among input, accumulation, release of P and as a consequence degrading water quality in terms of chlorophyll-a （Chl-a） in freshwater fishponds, fourteen fishponds with feed supply, nine fishponds without feed supply, and five nonfish ponds in Shaoxing Plain, southeast China were selected for comparing P accumulation in their waters and surface sediments. Surface sediment samples were collected from each pond to evaluate their total P, water soluble P, Olsen P, algal available P, and P fractions. Water samples were also collected from the ponds to measure concentrations of dissolved P and Chl-a. Total P in the sediments ranged from 0.88 to 1.73 g/kg in the fishponds with feed supply, that in the non-fish ponds ranged from 0.47 to 0.86 g/kg. Organic P, accounted for 23% to 60% of total P in the sediments, was an important P fraction and increased linearly with increasing organic matter. Long-term application of feeds resulted in increased P availability in the bottom sediments and degradation of water quality in the freshwater fishponds. Compared with non-fish ponds, sediments from the feed-supplied fishponds contained considerably higher Olsen P, algal available P, and water soluble P. Higher proportions of the labile P （NH4Cl-P） and potentially labile P （NaOH-IP） were also found in the sediments from the fishponds. High solubility of P in the sediments resulted in elevation of P and chlorophyll-a concentration in the pond water. The dissolved P concentration in the pond water increased in the order of non-fish ponds （12μg/L）〈 fishponds without feed supply （24 μg/L）〈 fishponds with feed supply （66 μg/L）. Linear correlations between concentrations of total P, Olsen-P, algal avail

关键词： eutrophication freshwater fishery phosphorus fraction water quality

Effect of temperature and heating rate on mechanical properties of magnesium alloy AZ31

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Transactions of Nonferrous Metals Society of China 2010年第B7期20卷 426-429页

作者：袁权陈斌罗吉张丁非权国政 college of resources and environmental Science Chongqing University Key Laboratory for Exploitation of Southwest resources and environmental Disaster Control Engineering Ministry of EducationChongqing University college of Materials Science and Engineering Chongqing University

Effects of temperature and heating rate on the mechanical properties of the tensile specimens of magnesium alloy AZ31 were experimentally investigated using a Gleeble-1500 thermo-mechanical material testing *** metallurgraphs of the fracture section of the specimens were also experimentally observed and analyzed for exploring their failure mechanism under different temperatures and heating *** results show that the higher the temperature,the lower the ultimate strength of the *** the higher the heating rate,the higher the ultimate strength of the *** high temperatures and high heating rates will induce microvoids in the specimens which make the specimens failure under relatively low loads.

关键词： AZ31 magnesium alloy temperature heating rate strength plasticity

Effect of heating-rate on failure temperature of pre-loaded magnesium alloy

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Transactions of Nonferrous Metals Society of China 2010年第B7期20卷 371-375页

作者：罗吉陈斌袁权张丁非权国政 college of resources and environmental Science Chongqing University Key Laboratory for Exploitation of Southwest resources and environmental Disaster Control Engineering Ministry of EducationChongqing University college of Materials Science and Engineering Chongqing University

The response and failure of magnesium alloy AZ31 specimens subjected to different pre-loaded-stress levels and heating rates were investigated with a Gleeble-1500 thermo-mechanical material testing *** is found that the increases of either pre-loaded stresses or heating-rates decrease the failure temperatures of the *** metallographs of the tested specimens were also *** is shown that the high heating-rate may cause stronger local thermal inconsistency,which remarkably increases the microdefects and reduces the macroscopic mechanical properties of the material.

关键词： magnesium alloy AZ31 pre-loaded stress heating rate failure temperature local thermal inconsistency

Effect of Nitrate on Activities and Transcript Levels of Nitrate Reductase and Glutamine Synthetase in Rice

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Pedosphere 2008年第5期18卷 664-673页

作者： CAO Yun FAN Xiao-Rong SUN Shu-Bin XU Guo-Hua HU Jiang SHEN Qi-Rong college of resources and environmental Sciences Nanjing Agricultural University Nanjing 210095 （China）.

Real-time polymerase chain reaction analysis was used to compare the effect of NO3^- on the activities of nitrate reductase （NR） and glutamine synthetase （GS）, and the transcript levels of two NR genes, OsNial and OsNia2, two cytosolic GS1 genes, OsGln1;1 and OsGln1;2, and one plastid GS2 gene OsGln2, in two rice （Oryza sativa L.） cultivars Nanguang （NG） and Yunjing （Y J）. Both cultivars achieved greater biomass and higher total N concentration when grown in a mixed N supply than in sole NH4^＋ nutrition. Supply of NO3^- increased NR activity in both leaves and roots. Expression of both NR genes was also substantially enhanced and transcript levels of OsNia2 were significantly higher than those of OsNial. NO3 also caused an increase in GS activity, but had a complex effect on the expression of the three GS genes. In roots, the OsGln1;1 transcript increased, but OsGln1;2 decreased. In leaves, NO3^- had no effect on the GS1 expression, but the transcript for OsGln2 increased both in the leaves and roots of rice with a mixed supply of N. These results suggested that the increase in GS activity might be a result of the complicated regulation of the various GS genes. In addition, the NO3-induced increase of biomass, NR activity, GS activity, and the transcript levels of NR and GS genes were proportionally higher in NG than in Y J, indicating a stronger response of NG to NO3^- nutrition than YJ.

关键词： ammonium glutamine synthetase nitrate nitrate reductase Oryza sativa L.

Nature Experience, Recreation Activity and Health Benefits of Visitors in Mountain and Urban Forests in Vienna, Zurich and Freiburg

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Journal of Mountain Science 2015年第6期12卷 1551-1561页

作者： Ju-hyoung LEE Duk-jae LEE Department of Forest resources Faculty of Natural Resources Yeungnam University Department of Forest resources College of Life & Environmental Science Daegu University

Mountain forests are managed for various purposes. Of these, recreation, leisure, and ecotourism are increasingly gaining prominence. Yet, with the development of new techniques for creating and managing urban forests, the perception of the public with regard to mountain forests and such urban forests is narrowing. For the purpose of this study, eight mountain forests and urban forests located in Zurich(Switzerland), Vienna(Austria) and Freiburg(Germany) were shortlisted. These places are renowned for their well-functioning management of mountain forests and creation of urban forests. As the study was to focus on the comparison of the perceptions of visitors in terms of their satisfaction in urban and mountain forests, the interview covered the following questions:(i) how satisfactory was the nature experience;(ii) how satisfactory were the outdoor recreational activities;(iii) whether the nature experiences influenced the mental and physical health of visitors. Responses thus received for each of the mountain forests and urban forests were assessed, with the total number of respondents being 247. Tourists visiting the selected areas were randomly chosen for a one-on-one interview survey. Results of the survey show that there is a clear perceptions of visitors differed between urban and mountain forests. However, the gap is insignificant or almost nonexistent with respect to satisfaction level of outdoor recreational activities and health benefits. These results are contrary to the findings of previous studies, which argued that the natural landscape of mountain areas is superior to other artificially built green spaces. Visitors did not perceive significant differences in outdoor recreational activities and health effects between the two spaces.

关键词： Europe Satisfaction Outdoor recreation Interview survey Preference