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Evaluation of Latest TMPA and CMORPH Precipitation Products with Independent Rain Gauge Observation Networks over High-latitude and Low-latitude Basins in China 被引量:11
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作者 JIANG Shanhu REN Liliang +3 位作者 YONG Bin HONG Yang YANG Xiaoli YUAN Fei 《Chinese Geographical Science》 SCIE CSCD 2016年第4期439-455,共17页
The Tropical Rainfall Measuring Mission (TRMM) Multi-satellite Precipitation Analysis (TMPA) and National Oceanic and Atmospheric Administration (NOAA) Climate Prediction Center (CPC) morphing technique (CMO... The Tropical Rainfall Measuring Mission (TRMM) Multi-satellite Precipitation Analysis (TMPA) and National Oceanic and Atmospheric Administration (NOAA) Climate Prediction Center (CPC) morphing technique (CMORPH) are two important multi-satellite precipitation products in TRMM-era and perform important functions in GPM-era. Both TMPA and CMORPH systems simultaneously upgraded their retrieval algorithms and released their latest version of precipitation data in 2013. In this study, the latest TMPA and CMORPH products (i.e., Version-7 real-time TMPA (T-rt) and gauge-adjusted TMPA (T-adj), and Version- 1.0 real-time CMORPH (C-rt) and Version-l.0 gauge-adjusted CMORPH (C-adj)) are evaluated and intercompared by using independent rain gauge observations for a 12-year (2000--2011) period over two typical basins in China with different geographical and climate conditions. Results indicate that all TMPA and CMORPH products tend to overestimate precipitation for the high-latitude semiarid Laoha River Basin and underestimate it for the low-latitude humid Mishui Basin. Overall, the satellite precipitation products exhibit superior performance over Mishui Basin than that over Laoha River Basin. The C-adj presents the best performance over the high-latitude Laoha River Basin, whereas T-adj showed the best performance over the low-latitude Mishui Basin. The two gauge-adjusted products demonstrate potential in water resource management. However, the accuracy of two real-time satellite precipitation products demonstrates large variability in the two validation basins. The C-rt reaches a similar accuracy level with the gauge-adjusted satellite precipitation products in the high-latitude Laoha River Basin, and T-rt performs well in the low-latitude Mishui Basin. The study also reveals that all satellite precipitation products obviously overestimate light rain amounts and events over Laoha River Basin, whereas they underestimate the amount and events over Mishui Basin. The findings of the precision characteristics associated with the latest TMPA and CMORPH precipitation products at different basins will offer satellite pre- cipitation users an enhanced understanding of the applicability of the latest TMPA and CMORPH for water resource management, hydrologic process simulation, and hydrometeorological disaster prediction in other similar regions in China. The findings will also be useful for IMERG algorithm development and update in GPM-era. 展开更多
关键词 satellite precipitation Tropical Rainfall Measuring Mission (TRMM) Multi-satellite Precipitation Analysis (TMPA) Cli-mate Prediction Center morphing technique (CMORPH) precision evaluation
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The eco-nutrition requirements for dietary protein and its rhomb characteristics in juvenile turbot (Scophthalmus maximus L.) 被引量:4
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作者 李勇 蒋克勇 +2 位作者 孙国祥 高婷婷 周邦维 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2011年第5期1002-1008,共7页
We evaluated the dietary protein requirements of juvenile turbot (Scophthalmus maximus L.) and their effects on aquatic quality. Five experimental diets were formulated containing 450, 480, 500, 520, and 540 g/kg. Eac... We evaluated the dietary protein requirements of juvenile turbot (Scophthalmus maximus L.) and their effects on aquatic quality. Five experimental diets were formulated containing 450, 480, 500, 520, and 540 g/kg. Each diet was randomly assigned to triplicate groups of juvenile turbot (mean initial body weight 34.5 ± 5.5 g) for 88 d. Both the weight gain ratio and feed efficiency increased with increasing dietary protein up to 500 g/kg, but no further improvement was detected when dietary protein levels were >500 g/kg. Protein intake and digestion increased with protein levels, while fecal nitrogen and nitrogen content in seawater increased only when dietary protein exceeded 500 g/kg. Protein digestibility was highest at intermediate dietary protein levels. Chemical oxygen demand, nitrite-nitrogen (NO2--N) and phosphatic-phosphor (PO43--P) levels increased in the rearing water as dietary protein levels increased. The optimum eco-nutrition level of dietary protein for juvenile turbot was 500 g/kg under the current experimental conditions. The diets containing 540 and 500 g/kg protein had similar growth rates and feed conversion ratios, but levels of ammonia (NH4+) and nitrogen were considerably higher in the water and feces, respectively, at the higher level of dietary protein. The difference in the pattern of change between body weight gain and ammonia concentration in water with increasing dietary protein is described by rhomb characteristics. 展开更多
关键词 eco-nutrition requirement rhomb characteristics protein aquatic quality DIGESTION TURBOT
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Rheological and Structural Properties of Sea Cucumber Stichopus japonicus During Heat Treatment 被引量:13
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作者 GAO Xin XUE Dongmei +2 位作者 ZHANG Zhaohui XU Jiachao XUE Changhu 《Journal of Ocean University of China》 SCIE CAS 2005年第3期244-247,共4页
Changes in tissue structure, rheological properties and water content of raw and heated sea cucumber meat were studied. Sea cucumber Stichopus japonicus was heated at 25℃, 70℃ and 100℃ water for 5 min. The structur... Changes in tissue structure, rheological properties and water content of raw and heated sea cucumber meat were studied. Sea cucumber Stichopus japonicus was heated at 25℃, 70℃ and 100℃ water for 5 min. The structural changes were observed using a light microscope and the rheological parameters (rupture strength, adhesive strength and deformation) determined using a texture meter. Microscopic photograph revealed that the structural change of heated meat was greater than that of raw meat. The rupture strength, adhesive strength and deformation of raw meat were smaller than those of the heated meat. Meanwhile, rheological parameters showed positive correlation with heating temperature. These changes are mainly caused by thermal denaturation and gelatinization of collagen during heating. These changes were also evidenced in observations using a light microscope and differential scanning calorimetry. 展开更多
关键词 sea cucumber COLLAGEN muscle fibers rheological properties
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High efficiency of protoplast preparation for artificially cultured Ulva prolifera(Ulvophyceae,Chlorophyta) 被引量:1
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作者 WU Chunhui JIANG Peng +1 位作者 ZHAO Jin FU Huihui 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2018年第5期1806-1811,共6页
Protoplast isolation was relevant for gene manipulation in U lva, and universal protocols have been proposed based on evaluation for various wildly collected species. However, only clonal laboratory cultures were prac... Protoplast isolation was relevant for gene manipulation in U lva, and universal protocols have been proposed based on evaluation for various wildly collected species. However, only clonal laboratory cultures were practical for genetic transformation, and whether applicability of such universal protocol existed for these artificial cultures has never been investigated. In this research, samples in different physiological states or developmental stages were tested in U. prolifera. The results proved that the protoplast yields were strongly dependent on the characteristics of samples. Neither F_v/F_m value nor chlorophyll content exhibited an ideal correlation with the protoplast yields. Alternatively, specific growth rate, coupled with developmental stage, could serve as an ef fective combined index to determine the right time for protoplast isolation. According to this instruction, here we reported the highest yields of protoplast((31.5±1.9)×10~6 cells/g f. wt.) in U. prolifera, following comparison between protocols, and further optimizations on enzyme content, incubation period, starting biomass and pretreatment. This specified protocol for artificially cultured clonal samples could meet the need for protoplast-mediated genetic transformation in U. prolifera. 展开更多
关键词 PROTOPLAST Ulva prolifera regeneration artificial culture
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Analysis of volatile components in a Chinese fish sauce,Fuzhou Yulu, by gas chromatography-mass spectrometry 被引量:1
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作者 Yuan-fan YANG Shen-ru CHEN +1 位作者 Hui NI Xing-qian YE 《Journal of Zhejiang University-Science B(Biomedicine & Biotechnology)》 SCIE CAS CSCD 2008年第12期977-981,共5页
Volatile components of Fuzhou Yulu, a Chinese fish sauce, were analyzed by gas chromatography-mass spectrometry (GC-MS), and two pretreatment methods, i.e., purge and trap (P&T) GC-MS and ethyl acetate extraction... Volatile components of Fuzhou Yulu, a Chinese fish sauce, were analyzed by gas chromatography-mass spectrometry (GC-MS), and two pretreatment methods, i.e., purge and trap (P&T) GC-MS and ethyl acetate extraction followed by GC-MS, were compared. P&T-GC-MS method determined 12 components, including sulfur-containing constituents (such as dimethyl disulfide), nitrogen-containing constituents (such as pyrazine derivatives), aldehydes and ketones. Ethyl acetate extraction fol- lowed by GC-MS method detected 10 components, which were mainly volatile organic acids (such as benzenepropanoic acid) and esters. Neither of the two methods detected alcohols or trimethylamine. This study offers an important reference to determine volatile flavor components of traditional fish sauce through modem analysis methods. 展开更多
关键词 Fish sauce Fuzhou Yulu Volatile component Purge and trap Gas chromatography-mass spectrometry (GC-MS)
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Petrochemical wastewater treatment with a pilot-scale bioaugmented biological treatment system 被引量:5
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作者 ZHAO Li-jun MA Fang +1 位作者 GUO Jing-bo ZHAO Qing-liang 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2007年第11期1831-1838,共8页
In solving the deterioration of biological treatment system treating petrochemical wastewater under low temperatures, bioaugmentation technology was adopted by delivering engineering bacteria into a pilot-scale two-st... In solving the deterioration of biological treatment system treating petrochemical wastewater under low temperatures, bioaugmentation technology was adopted by delivering engineering bacteria into a pilot-scale two-stage anoxic-oxic (A/O) process based on previous lab-scale study. Experimental results showed that when the concentrations of COD and NH4+-N of the influent were 370~910 mg/L and 10~70 mg/L, the corresponding average concentrations of those of effluent were about 80 mg/L and 8 mg/L respectively, which was better than the Level I criteria of the Integrated Wastewater Discharge Standard (GB8978-1996). According to GC-MS analysis of the effluents from both the wastewater treatment plant (WWTP) and the pilot system, there were 68 kinds of persistent organic pollutants in the WWTP effluent, while there were only 32 in that of the pilot system. In addition, the amount of the organics in the effluent of the pilot system reduced by almost 50% compared to that of the WWTP. As a whole, after bioaugmentation, the organic removal efficiency of the wastewater treatment system obviously in- creased. 展开更多
关键词 BIOAUGMENTATION Petrochemical wastewater Pilot-scale study GC/MS
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High-yielding Cultivation and Fertilization Technology of Lvhan No.1 in Angola
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作者 杨前进 邱康键 +2 位作者 张显春 刘广辉 王斌 《Agricultural Science & Technology》 CAS 2012年第11期2296-2298,2346,共4页
[Objective] The aim was to research high-yielding cultivation and fertilization technology for Lvhan No.l, a new Chinese rice cultivar, in Angola. [Method] In rainy season of 2012, high-yielding cultivation and fertil... [Objective] The aim was to research high-yielding cultivation and fertilization technology for Lvhan No.l, a new Chinese rice cultivar, in Angola. [Method] In rainy season of 2012, high-yielding cultivation and fertilization technology of Lvhan No.l, a new cultivar of earlier ripe and drought resistant rice, was researched in CATETE farm of Luanda suburb with pot experiment method. [Result] In CATETE farm, Lvhan No.1 rice were directly sown in black clay and the rice can be significantly improved in plant height, grain weight of single plant, biological yield of single plant, ear length, total grain number per ear, number of filled grain per ear and thousand seed weight, as well as economic coefficient and ratio of grain to straw, if applied with base fertilizer made up of DAP (N:P2Os=14:43), or compound fertilizer of N, P and K (N:P2Os:K^O=15:15:15) and with Duannai fertilizer and ear-grain fertilizer made up of urea. If DAP is taken as base fertilizer, the optimal quantity is 300 kg/hm2. If compound fertilizer of N, P and K is taken as base fertilizer, the optimal quantity is 450 kg/hm2, but urea at 75 kg/hm2 should be applied as Duannai fertilizer and ear- grain fertilizer, respectively, on time. [Conclusion] The research provides technical ref- erences for planting of Chinese rice cultivars in Angola. 展开更多
关键词 Lvhan No.l ANGOLA Fertilization technology
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Chemical probing reveals insights into the signaling mechanism of inflammasome activation 被引量:5
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作者 Yi-Nan Gong Xiaoming Wang +6 位作者 Jiayi Wang Zhenxiao Yang Shan Li Jieling Yang Liping Liu Xiaoguang Lei Feng Shao 《Cell Research》 SCIE CAS CSCD 2010年第12期1289-1305,共17页
Caspase-1-mediated IL-1β production is generally controlled by two pathways. Toll-like receptors (TLRs) recognize pathogen-derived products and induce NF-KB-dependent pro-IL-1β transcription; NOD-like receptors (... Caspase-1-mediated IL-1β production is generally controlled by two pathways. Toll-like receptors (TLRs) recognize pathogen-derived products and induce NF-KB-dependent pro-IL-1β transcription; NOD-like receptors (NLRs) assemble caspase-l-activating inflammasome complexes that sense bacterial products/danger signals. Through a targeted chemical screen, we identify bromoxone, a marine natural product, as a specifc and potent inhibitor of the caspase-1 pathway. Bromoxone is effective over diverse inflammatory stimuli including TLR ligands plus ATP/nigeri- cin, cytosolic DNA, flagellin and Bacillus anthracis lethal toxin. Bromoxone also efficiently suppresses easpase-1 acti- vation triggered by several types of bacterial infection. Bromoxone acts upstream or at the level of the inflammasome in a transcription-independent manner. Bromoxone also inhibits pro-IL-1β expression by targeting components up- stream of IKK in the TLR-NF-kB pathway. The unique dual activities of bromoxone are shared by the known TAK1 inhibitor that specifically blocks Nalp3 inflammasome activation. Hinted from the mechanistic and pharmacological properties of bromoxone, we further discover that several known NF-KB inhibitors that act upstream of IKK, but not those targeting IKK or IKK downstream, are potent blockers of different NLRs-mediated caspase-1 activation. Our study uncovers a possible non-transcriptional molecular link between the NLR (Nalp3)-mediated inflammasome pathway and TLR-NF-kB signaling, and suggests a potential strategy to develop new anti-inflammatory drugs. 展开更多
关键词 innate immunity INFLAMMASOME NOD-like receptors chemical biology signal transduction
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Growth and Feed Efficiency of Juvenile Shrimp Litopenaeus vannamei Fed Formulated Diets Containing Different Levels of Poultry by-Product Meal 被引量:7
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作者 CHI Shuyan TAN Beiping +1 位作者 MAI Kangsen ZHENG Shixuan 《Journal of Ocean University of China》 SCIE CAS 2009年第4期399-403,共5页
This feeding trial was conducted to evaluate the potential of poultry by-product meal (PBM) as a protein source in the culture of Litopenaeus vannamei. Seven isonitrogenous and isoenergetic diets were formulated to ne... This feeding trial was conducted to evaluate the potential of poultry by-product meal (PBM) as a protein source in the culture of Litopenaeus vannamei. Seven isonitrogenous and isoenergetic diets were formulated to near to commercial diet with about 40% protein and 7.5% lipid. Fish meal was replaced by 0, 30%, 40%, 50%, 60%, 70% and 100% of PBM (diets 1-7). The diet with 100% fish meal was used as a control (diet 1). Post-larvae were reared in an indoor semi-closed re-circulating system. Each dietary treatment was tested in 4 replicate tanks (260 L) of 40 shrimp, arranged in a completely randomized design. The shrimps were hand-fed for three times a day to near-satiation (0700, 1200 and 1800) for 60 d. Percentage weight gain, survival, feed conversion ratio (FCR), protein efficiency ratio (PER) and body composition of shrimps were measured. There were no significant differences (P>0.05) in growth performance among shrimps fed diets 1-5 (0-60% fish meal replacement). However, shrimps fed diet 7 (100% fish meal replacement) had significantly lower (P<0.05) growth than those fed diets 1-5 (0-60% fish meal replacement). Shrimp fed diets 2-4 (30%-50% fish meal replacement) showed significantly higher growth than those fed diets 6 and 7 (70% and 100% fish meal replacement, respectively). Survival ranged from 94.7% to 100.0% and did not differ significantly (P>0.05) among different experimental diets. No differences in body composition were found among shrimps fed different diets. These results showed that up to 70% of fish meal protein can be replaced by PBM without adversely affecting the growth, survival, FCR, PER and body composition of Litopenaeus vannamei. 展开更多
关键词 Litopenaeus vannamei poultry by-product meal fish meal REPLACEMENT
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Evaluation of CMPAS precipitation products over Sichuan,China 被引量:2
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作者 Shiying Li Xiaolong Huang +2 位作者 Wei Wu Bing Du Yuhe Jiang 《Atmospheric and Oceanic Science Letters》 CSCD 2022年第2期47-53,共7页
High-quality and high-resolution precipitation data are the basis for mesoscale numerical weather forecasting,model verification,and hydrological monitoring,which play an important role in meteorological and hydrologi... High-quality and high-resolution precipitation data are the basis for mesoscale numerical weather forecasting,model verification,and hydrological monitoring,which play an important role in meteorological and hydrological disaster prevention and mitigation.In this study,high-density rain gauge data are used to evaluate the fusion accuracy of the China Meteorological Administration Multisource Precipitation Analysis System(CMPAS),and four CMPAS products with different spatial and temporal resolution and different data sources are compared,to derive the applicability of CMPAS.Results show that all the CMPAS products show high accuracy in the Sichuan Basin,followed by Panxi Area and the western Sichuan Plateau.The errors of the four products all rise with the increase in precipitation.CMPAS overestimates precipitation in summer and autumn and underestimates it in spring and winter.Overall,the applicability of these fused data in the Sichuan Basin is quite good.Due to the lack of observations and the influence of the terrain and meteorological conditions,the evaluation of CMPAS in the plateau area needs further analysis. 展开更多
关键词 Multisource precipitation products High-resolution precipitation CMPAS Applicability assessment
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Study on Modification of Ultra-Stable Zeolite Prepared by Hydrothermal Method 被引量:2
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作者 Zhang Weilin Zhou Lingping +4 位作者 Shen Shimin Li Zheng Zhu Yuxia Tian Huiping Long Jun 《China Petroleum Processing & Petrochemical Technology》 SCIE CAS 2007年第2期55-59,共5页
The ultra-stable zeolite DASY-0.0 was prepared by hydrothermal method in commercial scale. Its structure was further modified via the treatment for cleaning of pores (CP). The zeolite samples before and after CP tre... The ultra-stable zeolite DASY-0.0 was prepared by hydrothermal method in commercial scale. Its structure was further modified via the treatment for cleaning of pores (CP). The zeolite samples before and after CP treating were analyzed and characterized by XRF, XRD, NMR, IR, BET and DTA. The results showed that, in comparison with the conventional ultra-stable zeolite DASY-0.0 prepared by the hydrothermal process, the CP-modified zeolite SOY0 exhibited a higher relative crystallinity, a larger surface area and pore volume, a higher thermal stability and contained less amorohous non-framework A1. 展开更多
关键词 ZEOLITE ultra-stable MODIFICATION thermal stability
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Potential Hazards in Smoke-Flavored Fish
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作者 LIN Hong JIANG Jie LI Donghua 《Journal of Ocean University of China》 SCIE CAS 2008年第3期294-298,共5页
Smoking is widely used in fish processing for the color and flavor. Smoke flavorings have evolved as a successful alternative to traditional smoking. The hazards of the fish products treated by liquid-smoking process ... Smoking is widely used in fish processing for the color and flavor. Smoke flavorings have evolved as a successful alternative to traditional smoking. The hazards of the fish products treated by liquid-smoking process are discussed in this review. The smoke flavoring is one important ingredient in the smoke-flavored fish. This paper gives the definition of smoke flavorings and the hazard of polycyclic aromatic hydrocarbons (PAHs) residue in the smoke flavorings on the market. It gives also an assessment of chemical hazards such as carcinogenic PAHs, especially Benzo-[α]pyrene, as well as biological hazards such as Listeria monocytogenes, Clostridium botulinum, histamine and parasites in smoke-flavored fish. The limitations in regulations or standards are discussed. Smoke flavored fish have lower content of PAHs as compared with the traditional smoking techniques if the PAHs residue in smoke flavorings is controlled by regulations or standards. 展开更多
关键词 smoke-flavored fish hazards smoke flavoring PAHS
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Automatic Data Extraction from Websites for Generating Aquatic Product Market Information
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作者 袁红春 陈莹 孙越夫 《Journal of Donghua University(English Edition)》 EI CAS 2006年第6期15-19,共5页
The massive web-based information resources have led to an increasing demand for effective automatic retrieval of target information for web applications. This paper introduces a web-based data extraction tool that de... The massive web-based information resources have led to an increasing demand for effective automatic retrieval of target information for web applications. This paper introduces a web-based data extraction tool that deploys various algorithms to locate, extract and filter tabular data from HTML pages and to transform them into new web-based representations. The tool has been applied in an aquaculture web application platform for extracting and generating aquatic product market information. Results prove that this tool is very effective in extracting the required data from web pages. 展开更多
关键词 web data table localization algorithm distance algorithm data filtering algorithm data extraction tool.
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Blended coals for improved coal water slurries 被引量:2
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作者 GU Tian-ye WU Guo-guang LI Qi-hui SUN Zhi-qiang ZENG Fang WANG Guang-you MENG Xian-liang 《Journal of China University of Mining and Technology》 EI 2008年第1期50-54,共5页
Three coal samples of different ranks were used to study the effect of coal blending on the preparation of Coal Water Slurry (CWS). The results show that by taking advantage of two kinds of coal, the coal concentratio... Three coal samples of different ranks were used to study the effect of coal blending on the preparation of Coal Water Slurry (CWS). The results show that by taking advantage of two kinds of coal, the coal concentration in slurry made from hard-to-pulp coal can be effectively improved and increased by 3%–5% generally. DLT coal (DaLiuTa coal mine) is very poor in slurryability and the stability and rheology of the resulting slurry are not very good. When the amount of easily slurried coal is more than 30%, all properties of the CWS improve and the CWS meets the requirements for use as fuel. Coalification, porosity, surface oxygenic functional groups, zeta potential and grindability have a great effect on the performance of blended coal CWS. This leads to some differences in performance between the slurry made from a single coal and slurry made from blended coal. 展开更多
关键词 low rank coal coal water slurry coal blending SLURRYABILITY zeta potential
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Genotypic Differences in Grain Yield and Physiological Nitrogen Use Efficiency Among Rice Cultivars 被引量:30
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作者 ZHANG Ya-Li, FAN Jian-Bo, WANG Dong-Sheng and SHEN Qi-Rong2College of Resources and Environmental Sciences, Nanjing Agricultural University, Nanjing 210095 (China) 《Pedosphere》 SCIE CAS CSCD 2009年第6期681-691,共11页
Efficient use of N in agricultural practice can increase yield, decrease production costs and reduce the risk of environmental pollution. Effects of N fertilizer application rates on grain yield and physiological N us... Efficient use of N in agricultural practice can increase yield, decrease production costs and reduce the risk of environmental pollution. Effects of N fertilizer application rates on grain yield and physiological N use efficiency (PE) in relation to the accumulation and redistribution of biomass and N in rice (Oryza sativa L.) cultivars were studied at two experimental farms of Nanjing Agricultural University, Nanjing, China in 2004. Three high N use efficiency (NUE) rice cultivars (Wuyunjing 7, Nanguang and 4007) and one low NUE rice cultivar (Elio) with similar growth patterns were studied under seven N rates (0, 60, 120, 180, 240, 300 and 360 kg ha -1 ). Grain yield increased with the N application rate and attained plateau at 180 kg N ha -1 for rice cultivars at each site. Increasing N rate decreased PE for biomass and grain yield. Grain yield and PE of Elio were about 20% and 18% lower than those of high NUE cultivars. Differences in biomass, N accumulation and N redistribution were observed at the post-heading stage among rice cultivars with differing NUEs. The less reproductive tillers of Elio resulted in less demand for C and N during grain filling, thus leading to lower PE of Elio compared with the high NUE rice cultivars. 展开更多
关键词 ACCUMULATION BIOMASS N application rate REDISTRIBUTION
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Determination of Selenium in Marine Aquatic Products by Hydride Generation-atomic Fluorescence Spectrometry (HG-AFS)
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作者 ZHANG Zhaohui GAO Xin +1 位作者 Tashiro Yuri Hiroo Ogawa 《Journal of Ocean University of China》 SCIE CAS 2005年第3期252-256,共5页
A method for the analysis of selenium in marine aquatic products by HG-AFS has been investigated. The method is based on the reduction of inorganic selenium to volatile SeH2 which is bubbled out by carrier gas of pure... A method for the analysis of selenium in marine aquatic products by HG-AFS has been investigated. The method is based on the reduction of inorganic selenium to volatile SeH2 which is bubbled out by carrier gas of pure argon, and then swept to Ar-H2 flame quarts atomizer to measure its fluorescence intensity. The hydride generation, transportation, atomization and some instrumental parameters were studied by a kind of orthogonal design. The optimum conditions selected are as follows: reactive acidity, 20% HC1; the amount of NaBH4, 4.9mL; gas flow of argon, 600mLmin^-1; atomizing temperature, 200 ℃ ; negative high voltage, - 300V; light current, 100 mA; integral time, 7s. The detection limit of the presented method is 0.072μgL^-1 for selenium. The calibration curve shows a satisfactory line inthe concentration range from 0.000 to 1.000μgL^-1 Se. The recovery is 95.8%-102.2%. 展开更多
关键词 hydride generation-atomic fluorescence spectrometry(HG-AFS) SELENIUM marine aquatic products
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Effect of coal levels during direct reduction roasting of high phosphorus oolitic hematite ore in a tunnel kiln 被引量:24
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作者 Li Yongli Sun Tichang Zou Anhua Xu Chengyan 《International Journal of Mining Science and Technology》 SCIE EI 2012年第3期323-328,共6页
The effect of coal levels on phosphorus removal from a high phosphorus oolitic hematite ore after direct reduction roasting have been investigated. Raw ore, coal, and a dephosphorizatiou agent were mixed and the mixtu... The effect of coal levels on phosphorus removal from a high phosphorus oolitic hematite ore after direct reduction roasting have been investigated. Raw ore, coal, and a dephosphorizatiou agent were mixed and the mixture was then roasted in a tunnel kiln. The roasted products were treated by two stages of grind- ing followed by magnetic separation. XRD and SEM-EDS examination of the products was used to analyze differences in the roasted products. The results show that coal is one of the most important factors affect- ing the direct reduction roasting process. When the inner coal levels increased from 0% to 15% the iron grade decreased linearly from 94.94%to 88.81% and the iron recovery increased from 55.94% to 92.94%. At the same time the phosphorus content increased from 0.045% to 0.231%. Increasing the inner coal levels also caused more hematite to be reduced to metallic iron but the oolitic structure of the roasted product was preserved in the presence of high coal loading. The phase of the phosphorus in raw ore was not changed after direct reduction roasting. The effect of coal on the phosphorus content in the H-concentrate arises from changes in the difficulty of mechanically liberating the metallic iron from the phosphorus bearing minerals. 展开更多
关键词 High phosphorus oolitic hematiteDirect reduction roastingRemoval phosphorusMagnetic separation
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Rice Yield and Yield Components as Influenced by Phosphorus and Nitrogen Application Rates in the Moist Savanna of West Africa 被引量:1
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作者 Christopher J. Okonji Kehinde A. Okeleye +4 位作者 Sylvester O. Oikeh Sunday G. Aderibigbe Francis E. Nwilene Olupomi Ajayi Akeem A. Oyekanmi 《Journal of Agricultural Science and Technology(B)》 2012年第12期1214-1223,共10页
A two-year field experiment was conducted to evaluate the influence of nitrogen (0, 30, 60, and 120 kg N ha^-1) and phosphorus (0, 30, and 60 kg P2O5 ha^-1) application on grain yield and yield components of five ... A two-year field experiment was conducted to evaluate the influence of nitrogen (0, 30, 60, and 120 kg N ha^-1) and phosphorus (0, 30, and 60 kg P2O5 ha^-1) application on grain yield and yield components of five New Rice for Africa (NERICA) cultivars, their parents, and a check on a degraded soil in the moist savanna of Nigeria. Nerica 14 recorded the highest grain yield of 1.3 mg halcompared to the other NERICA cultivars. It also produced significantly (P 〈 0.05) longer panicles (19.24 cm), higher sink capacity as determined by thousand-kernel weight (30.3 g), and a higher potential for partitioning photosynthates (45.15%) into grains than the other cultivars. N × P interaction effect on grain yield was significant (P 〈 0.05) with moderate P (60 kg P2O5 ha^1) and moderate N (60 kg N ha^-1) resulting in optimum grain yield (1.7 mg ha^-1). Thus, moderate N and P were recommended for the production of NERICA varieties in low-input smallholder upland rice production systems of the moist savanna of Nigeria. 展开更多
关键词 Moist savanna NERICA rice nitrogen Oryza sativa PHOSPHORUS upland.
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Cement industry control system based on multi agent
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作者 王海东 邱冠周 黄圣生 《Journal of Central South University of Technology》 EI 2004年第1期41-44,共4页
Cement production is characterized by its great capacity, long-time delay, multi variables, difficult measurement and multi disturbances. According to the distributed intelligent control strategy based on the multi (a... Cement production is characterized by its great capacity, long-time delay, multi variables, difficult measurement and multi disturbances. According to the distributed intelligent control strategy based on the multi (agent,) the multi agent control system of cement production is built, which includes integrated optimal control and diagnosis control. The distributed and multiple level structure of multi agent system for the cement control is studied. The optimal agent is in the distributed state, which aims at the partial process of the cement production, and forms the optimal layer. The diagnosis agent located on the diagnosis layer is the diagnosis unit which aims at the whole process of the cement production, and the central management unit of the system. The system cooperation is realized by the communication among optimal agents and diagnosis agent. The architecture of the optimal agent and the diagnosis agent are designed. The detailed functions of the optimal agent and the diagnosis agent are analyzed. At last the realization methods of the agents are given, and the application of the multi agent control system is presented. The multi agent system has been successfully applied to the off-line control of one cement plant with capacity of 5 000 t/d. The results show that the average yield of the clinker increases 9.3% and the coal consumption decreases 7.5 kg/t. 展开更多
关键词 AGENT multi agent system CEMENT PRODUCTION process control
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Elimination of Foodborne Pathogens in Seafoods by Irradiation: Effects on the Quality and Shelf-Life
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作者 Ismail Yuksel Genc Abdullah Diler 《Journal of Food Science and Engineering》 2013年第2期99-106,共8页
Animal originated contamination is the main problem of public health and causes human suffering all over the world. Nowadays, radiation technology is used on foods and yielded with positive results. Gamma radiation ca... Animal originated contamination is the main problem of public health and causes human suffering all over the world. Nowadays, radiation technology is used on foods and yielded with positive results. Gamma radiation causes damage in the structure of bacterial DNA and cell walls. This irritation can lead to decrease in bacterial growth such as spoilage and pathogenic organisms (i.e, Salmonella spp., Bacillus cereus, Listeria monocytogenes, Yersinia enterocolitica, Staphylococcus aureus, Escherichia coli O 157:H7) by this means, increased quality and shelf-life can be obtained. However, for the maintaining organoleptic and nutritional quality, it is an obligation to achive the lowest levels of doses according to chemical, physical, microbiological properties of the product. Radiation energy can lead to radiolytic products from lipids, proteins and water which are the maj or components of seafoods. Another problem in seafood industry is quality losses at the retail and distribution. Time-temperature integrations are the major factors affecting the bacterial growth and enzymatic activity on the loss of seafood quality. The purpose of this review is to summarize the available information on the elimination of some food pathogens by irradition, which emphasize the effects of gamma irradiation on the quality and shelf-life of seafoods. 展开更多
关键词 Gamma radiation SEAFOODS PATHOGEN QUALITY shelf-life.
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