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Prediction of Low Heating Value of Sugar Cane Bagasse as a Fuel for Industrial Boilers in the High Relative Humidity Region: Case of Cameroon
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作者 Pierre Kana-Donfack Maxell Tientcheu-Nsiewe +1 位作者 Denis Tcheukam-Toko César Kapseu 《Open Journal of Applied Sciences》 2024年第6期1604-1624,共21页
Many attempts have been made to estimate calorific value of bagasse using mathematical equations, which were created based on data from proximate, ultimate, physical and chemical analysis. Questions have been raised o... Many attempts have been made to estimate calorific value of bagasse using mathematical equations, which were created based on data from proximate, ultimate, physical and chemical analysis. Questions have been raised on the applicability of these equations in different parts of the globe. This study was initiated to tackle these problems and also check the most suited mathematical models for the Law Heating Value of Cameroonian bagasse. Data and bagasse samples were collected at the Cameroonian sugarcane factory. The effects of cane variety, age of harvesting, source, moisture content, and sucrose on the LHV of Cameroon bagasse have been tested. It was shown that humidity does not change within a variety, but changes from the dry season to the rainy season;the sugar in the rainy season is significantly different from that collected in the dry season. Samples of the same variety have identical LHV. LHV in the dry season is significantly different from LHV in the rainy season. According to the fact that this study was done for cane with different ages of harvesting, the maturity of Cameroonian sugarcane does not affect LHV of bagasse. Tree selected models are much superior tool for the prediction of the LHV for bagasse in Cameroon compared to others. The standard deviation of these validated models is around 200 kJ/kg compared to the experimental. Thus, the models determined in foreign countries, are not necessarily applicable in predicting the LHV of bagasse in other countries with the same accuracy as that in their native country. There was linear relationship between humidity, ash and sugar content in the bagasse. It is possible to build models based on data from physical composition of bagasse using regression analysis. 展开更多
关键词 Sugarcane Bagasse Relative Humidity ASH low Heating value
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Research on the Low-carbon-high-value Agriculture Technology in the Comprehensive Improvement of Intra-county Environment Pollution——Taking the Development of Cultivation and Breeding Industry in the Ecological Cyclic Agricultural Garden in Shaoshan Irri 被引量:4
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作者 李林杰 许振成 +5 位作者 罗琳 黄璜 李劲松 赵志彬 陈月华 何清林 《Meteorological and Environmental Research》 CAS 2010年第7期64-67,71,共5页
The comprehensive improvement strategy of intra-county environment pollution in the city and countryside was searched.By the research method which combined the microscopic view,the macroscopic view with the dynamic pe... The comprehensive improvement strategy of intra-county environment pollution in the city and countryside was searched.By the research method which combined the microscopic view,the macroscopic view with the dynamic perspective,the seriousness of rural water quality,soil and atmospheric pollution in Xiangxiang,Xiangtan and the surrounding areas in Shaoshan irrigated area was revealed.The control measure which was 'four-dimensional pollution in the city and countryside'—— low-carbon-high-value agriculture and the technology innovation was proposed.The low-carbon-high-value technology innovation industrialization demonstration in three parts which included the pre-production,mid-production and post-production deep-processing of cultivation and breeding industry in the ecological cyclic agricultural garden in Shaoshan irrigated area was the driving force.We tried to propel the low-carbon ecological cultivation and breeding industry which included the paddy rice,grass,tree,medicinal herbs and pig,cow,chick,duck,fish.We wanted to relieve the structural unbalance of previous cultivation and breeding industry,'cheap grain hurting the farmers' and the short-leg problem of social-economic-ecological benefit.The results showed that the low-carbon-high-value agricultural system was a poly-generation technology system which promoted the multi-level and grading utilization,saved the energy,reduced the consumption and cleaned the production based on the ecology. 展开更多
关键词 Comprehensive control of intra-county environment pollution Four-dimensional pollution in the city and countryside low-carbon-high-value agriculture Ecological cyclic agriculture Environmental safety-urban and rural cyclic coupling mode low-carbon-high-value technology innovation industrialization demonstration Processing-tree-medicinal herbs-grass-paddy rice-duck-cow-chick-pig-fish-marsh gas-tourism eco-project China
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Calorific values and ash contents of different parts of Masson pine trees in southern China 被引量:4
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作者 Wei-sheng ZENG Shou-zheng TANG Qian-hui XIAO 《Journal of Forestry Research》 SCIE CAS CSCD 2014年第4期779-786,共8页
Calorific value of plants is an important parameter for evalu- ating and indexing material cycles and energy conversion in forest eco- systems. Based on mensuration data of 150 sample sets, we analyzed the calorific v... Calorific value of plants is an important parameter for evalu- ating and indexing material cycles and energy conversion in forest eco- systems. Based on mensuration data of 150 sample sets, we analyzed the calorific value (CV) and ash content (AC) of different parts of Masson pine (Pinus massoniana) trees in southern China using hypothesis testing and regression analysis. CV and AC of different tree parts were almost significantly different (P〈0.05). In descending order, ash-free calorific value (AFCV) ranked as foliage 〉 branch 〉 stem bark 〉 root 〉 stem wood, and AC ranked as foliage 〉 stem bark 〉 root 〉 branch 〉 stem wood. CV and AC of stem wood from the top, middle and lower sections of trees differed significantly. CV increased from the top to the lower sections of the tnmk while AC decreased. Mean gross calorific value (GCV) and AFCV of aboveground parts were significantly higher than those of belowground parts (roots). The mean GCV, AFCV and AC of a whole tree of Masson pine were 21.54 kJ/g, 21.74 kJ/g and 0.90%, re- spectively. CV and AC of different tree parts were, to some extent, cor- related with tree diameter, height and origin. 展开更多
关键词 ash-free calorific value ash content gross calorific value hypothesis testing regression analysis Pinus massoniana
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Effect of tree-age on calorific value and other fuel properties of Eucalyptus hybrid 被引量:1
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作者 Ritesh Kumar K.K.Pandey +1 位作者 N.Chandrashekar Sanjai Mohan 《Journal of Forestry Research》 SCIE CAS CSCD 2010年第4期514-516,526,共4页
For determining the effect of tree-age on the fuel properties of Eucalyptus hybrid, the variability in basic density, calorific value, proximate and ultimate parameters of 2-6 years old trees and mature trees (20- ye... For determining the effect of tree-age on the fuel properties of Eucalyptus hybrid, the variability in basic density, calorific value, proximate and ultimate parameters of 2-6 years old trees and mature trees (20- year-old), grown under short rotation forestry regime, were measured and analyzed. Results show that there was no significant variation in the basic density of wood for 2-6 year-old Eucalyptus hybrid, with average value of 0.55-0.58 g.cm-3; the calorific value of mature trees was higher than that of lower age trees, but the ash content was much higher in lower age trees compared to mature trees. No particular trend was observed for volatile matter content and the fixed carbon content with tree-age. In conclusion, the fuel properties of mature tree were marginally better than trees of lower age. 展开更多
关键词 calorific value Eucalyptus hybrid fuel properties
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Numerical simulation of UCG process with the aim of increasing calorific value of syngas 被引量:1
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作者 Amin Jowkar Farhang Sereshki Mehdi Najafi 《International Journal of Coal Science & Technology》 EI 2020年第1期196-207,共12页
The determination of operational parameters in the underground coal gasification(UCG)process should be considered in two aspects:first,the total coal in each UCG panel must be gasified and second,the calorific value o... The determination of operational parameters in the underground coal gasification(UCG)process should be considered in two aspects:first,the total coal in each UCG panel must be gasified and second,the calorific value of the produced gas should be acceptable.The main aim of this study is to present a model that meets these aspects and increasing the calorific value of syngas during this process.In order to achieve those aims,eight different increasing scenarios were devised for total gasification of coal per panel.These scenarios included:increasing oxygen injection rate(scenario 1),the amount of steam injection(scenario 2),operation time(scenario 3),cavity pressure(scenario 4),increase operation time and cavity pressure simultaneously(scenario 5),increase steam injection speed and oxygen injection rate simultaneously(scenario 6),increase in cavity pressure,operating time,steam injection rate and oxygen injection rate simultaneously(scenario 7)and also simultaneous increase in the operating time and steam injection rate(scenario 8).The results showed that for producing syngas with a higher calorific value,the following parameters had the most positive effects respectively:operation time,cavity pressure,steam injection rate and oxygen injection rate.Finally,the model validation was performed for the Centralia LBK-1 UCG pilot and the results showed that this model is very close to reality. 展开更多
关键词 Underground coal gasification(UCG) CFD simulation Operational parameters calorific value of syngas
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An Evaluation of the Calorific Values of the Branches and Stems of 11 Tropical Trees 被引量:1
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作者 Jude I. Duruaku Vincent I. E. Ajiwe +1 位作者 Nkechi H. Okoye Rosemary U. Arinze 《Journal of Sustainable Bioenergy Systems》 2016年第2期44-54,共11页
This work investigated and quantified the calorific values of the main branches and trunks of eleven (11) tropical trees in correlation with their chemical composition in order to assess their suitability for use as c... This work investigated and quantified the calorific values of the main branches and trunks of eleven (11) tropical trees in correlation with their chemical composition in order to assess their suitability for use as credible sources of wood fuel. The determination of the carbon, hydrogen, nitrogen, oxygen and sulphur (CHNOS) content of the samples was done using an organic elemental analyser, while an oxygen bomb calorimeter was used to experimentally determine their corresponding gross heat values. The experimental gross heat values for the branches examined ranged from 18,703.37 kJ/kg in Lophira lanceolata to 21,350.35 kJ/kg in Afzelia africana while that of the trunks ranged from 19,747.74 kJ/kg in Tectonia grandis to 22,408.68 kJ/kg in Prosopis africana. These values were within and about the expected ranges observed for tropical trees and may be considered adequate for wood fuel. The general trend in both branches and trunks was that the higher the carbon content, the higher the gross heat value of sample. The absence of sulphur in almost all the samples except, Prosopis africana, (0.055%) was indicative of the fact that the negative environmental impact with respect to harmful emissions of oxides of sulphur is practically non-existent with respect to these species. In the light of the aforementioned variables, the main branches of Afzelia africana (21,350.35 kJ/kg), Nauclea diderrichii (21,157.30 kJ/kg) and Tectonia grandis (20,257.13 kJ/kg) could be used as credible sources of firewood and charcoal production. With respect to the trunks, the timbers in order of preference would ideally be Prosopis africana (22,408.68 kJ/kg), Nauclea diderichii (21,436.42 kJ/kg) and Brachstigia eurychoma (20,924.7 kJ/kg). 展开更多
关键词 calorific value Elemental Composition Gross Heat value Bulk Density Ash Content
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Evaluating the potential of(epi)genotype‑by‑low pass nanopore sequencing in dairy cattle:a study on direct genomic value and methylation analysis
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作者 Oscar Gonzalez‑Recio Adrian Lopez‑Catalina +3 位作者 Ramon Peiro‑Pastor Alicia Nieto‑Valle Monica Castro Almudena Fernandez 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2023年第6期2276-2289,共14页
Background Genotype-by-sequencing has been proposed as an alternative to SNP genotyping arrays in genomic selection to obtain a high density of markers along the genome.It requires a low sequencing depth to be cost ef... Background Genotype-by-sequencing has been proposed as an alternative to SNP genotyping arrays in genomic selection to obtain a high density of markers along the genome.It requires a low sequencing depth to be cost effective,which may increase the error at the genotype assigment.Third generation nanopore sequencing technology offers low cost sequencing and the possibility to detect genome methylation,which provides added value to genotype-by-sequencing.The aim of this study was to evaluate the performance of genotype-by-low pass nanopore sequencing for estimating the direct genomic value in dairy cattle,and the possibility to obtain methylation marks simultaneously.Results Latest nanopore chemistry(LSK14 and Q20)achieved a modal base calling accuracy of 99.55%,whereas previous kit(LSK109)achieved slightly lower accuracy(99.1%).The direct genomic value accuracy from genotype-by-low pass sequencing ranged between 0.79 and 0.99,depending on the trait(milk,fat or protein yield),with a sequencing depth as low as 2×and using the latest chemistry(LSK114).Lower sequencing depth led to biased estimates,yet with high rank correlations.The LSK109 and Q20 achieved lower accuracies(0.57-0.93).More than one million high reliable methylated sites were obtained,even at low sequencing depth,located mainly in distal intergenic(87%)and promoter(5%)regions.Conclusions This study showed that the latest nanopore technology in useful in a LowPass sequencing framework to estimate direct genomic values with high reliability.It may provide advantages in populations with no available SNP chip,or when a large density of markers with a wide range of allele frequencies is needed.In addition,low pass sequencing provided nucleotide methylation status of>1 million nucleotides at≥10×,which is an added value for epigenetic studies. 展开更多
关键词 Genomic selection Genomic values low pass sequencing low sequencing imputation Polygenic risk score
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Effect of Extractive Removal on the Calorific Value of Brazilian Woods Residues
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作者 Ticiane Rossi Luiz Femando de Moura Patricia R. Torquato Jose Otavio Brito 《Journal of Chemistry and Chemical Engineering》 2013年第4期340-343,共4页
In wood processing, the production of residues is an unavoidable aspect to be considered. The use of wood residues is gaining importance due to the large amount generated and improper disposal, which can seriously har... In wood processing, the production of residues is an unavoidable aspect to be considered. The use of wood residues is gaining importance due to the large amount generated and improper disposal, which can seriously harm environment. Burning of wood residues to energy generation is an increasingly usual practice. However, wood residues hold chemical substances that could be recovered before burning. These substances are the wood extractives, which may have many uses as natural dyes for fabrics, foods and cosmetics, as well as potential medicines. Thus, it is of great interest to study the effect of extractive removal on the calorific value of wood residues. In this work, the calorific value of three Brazilian wood species commonly used in sawmills (hymenaeacourbaril, jatoba; cedrelingacatenaeformis, cedroarana; tabebuiasp, ipe) and residues of urban trees pruning (caesalpiniaechinata, Brazil wood) were evaluated before and after extraction in hot water. In woods studied, the calorific value showed three patterns of behavior after removal of extractives soluble in hot water. For Brazil wood, the removal of extractives caused no significant change in calorific value. For cedroarana and jatoba, extractive removal led to a decrease in wood calorific value of 161.3 kcal.kg1 and 40. l kcal.kg^-1, respectively, which indicates that the extractives from these species have a positive energy potential. Finally, for ipe, the removal of extractives resulted in an increase in calorific value of wood (67.6 kcal.kg^-1), which might encourage the recovery of extractives from wood residues before burning for energy generation. 展开更多
关键词 calorific value EXTRACTIVES wood residues recovery.
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Study on Dynamics of Calorific Value, Biomass and Energy in Calamagrostis epigejos Population in Songnen Grassland 被引量:9
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作者 郭继勋 王若丹 王娓 《Acta Botanica Sinica》 CSCD 2001年第8期852-856,共5页
There were two peaks of seasonal changes of the calorific value in shoot and leaves of Calamagrostis epigejos in middle June and in the early August respectively. The calorific value in stem presented a single peak cu... There were two peaks of seasonal changes of the calorific value in shoot and leaves of Calamagrostis epigejos in middle June and in the early August respectively. The calorific value in stem presented a single peak curve which appeared in the early August. The calorific values in inflorescence and dead standing showed a fluctuation and the peak value of inflorescence was in the early September and that of dead standing was in middle June. The seasonal changes of energy standing crop on the above-ground part synchronized with that of the biomass, which presented a single peak curve. The energy allocated to each organ in different seasons was in the order as leaves > stem > inflorescence in middle June, leaves > stem > dead standing > inflorescence in early July, leaves > stem > inflorescence > dead standing in middle July, and leaves > stem > dead standing > inflorescence from August to September. The vertical allocation of energy in the parts of above-ground was that the energy value gradually increased from the surface to the 20 cm high level and the maximum value at the 10 - 20 cin high level which made up 26.91% of energy on the above-ground partion, and then it was decreased. In the under-ground portion, the energy value progressively decreased with depth and the maximum value was at 0 - 10 cm depth layer which made up 69.01% of energy of the under-ground portion. 展开更多
关键词 Calamagrostis epigejos calorific value ENERGY BIOMASS
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Study on the Monitoring Malfunction of Water Pollution during Drought or Flood Period and Low-carbon and High-value Methodology--A Case Study of the Correlation Test of Water,Soil and Gas Pollution in Xiangxiang County
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作者 LI Jin-song LI Lin-jie 《Meteorological and Environmental Research》 CAS 2011年第8期67-73,共7页
Based on the low-carbon and high-value methodology of chemical ecology and chemical informatics,combining theory and methods,taking saving,environmental protection,low carbon,high production,high value and circulation... Based on the low-carbon and high-value methodology of chemical ecology and chemical informatics,combining theory and methods,taking saving,environmental protection,low carbon,high production,high value and circulation as values and aims,the relationship between human and land as a basis,ecosystem as a center,overall control as a goal and agricultural ecological engineering as a mean,environmental pollution detection,as one of bottlenecks for agricultural products and food security,should be solved firstly;through the field survey in dry years from 2009 to 2010 when drought and flood were frequent and the frequency of drought was higher than that of flood,plus the determination of surface water flow and water quantity in a small typical river basin,the correlation of local water,soil and gas in the county could be found,and the transfer of monitoring focus from water environment to atmospheric environment was possible and necessary.The study would promote the quantitative research on the correlation among water,soil and gas,and the results were in accordance with the conclusions of related studies. 展开更多
关键词 Pollution monitoring REPRESENTATIVE Accuracy Correlation among water soil and gas data low-carbon and high-value methodology China
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Exploring relationships of gross calorific value and valuable elements with conventional coal properties for North Korean coals 被引量:4
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作者 Saeed Chehreh Chelgani 《International Journal of Mining Science and Technology》 SCIE EI CSCD 2019年第6期867-871,共5页
Coal in North Korean(NKC)is one of the most important products;however,based on various strategic policies its detail properties remain opaque even for general researchers.Since there are some signs for opening of the... Coal in North Korean(NKC)is one of the most important products;however,based on various strategic policies its detail properties remain opaque even for general researchers.Since there are some signs for opening of the North Korea economy,this investigation as a modest effort is going to explore principle relationships among some essential parameters of NKCs such as gross calorific value(GCV),valuable elements and conventional properties by different statistical methods.Correlations indicated that ultimate parameters(carbon,nitrogen,and hydrogen)are the best GCV predictors for NKCs in comparison with proximate parameters(ash,moisture and volatile matter).Multivariable regression demonstrated that predicted GCV based on ultimate properties has a quite accuracy when correlation of determination was 0.99.Descriptive statistics processes showed that on average,the contents of valuable elements such as Ga and V for NKCs are higher than the world coal ranges and they can be considered as byproducts of combustion of NKCs.Pearson correlations indicated that Y may have a mixed organic-inorganic affinity while Ga and V mainly occur in the inorganic part(mineral matter)of NKCs.High inter-correlations between Ga-V and Al showed that aluminosilicates can be considered as their main bring minerals. 展开更多
关键词 YTTRIUM GALLIUM VANADIUM calorific value Energy By product
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A novel model for cost performance evaluation of pulverized coal injected into blast furnace based on effective calorific value 被引量:4
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作者 徐润生 张建良 +3 位作者 左海滨 李克江 宋腾飞 邵久刚 《Journal of Central South University》 SCIE EI CAS CSCD 2015年第10期3990-3998,共9页
The combustion process of pulverized coal injected into blast furnace involves a lot of physical and chemical reactions. Based on the combustion behaviors of pulverized coal, the conception of coal effective calorific... The combustion process of pulverized coal injected into blast furnace involves a lot of physical and chemical reactions. Based on the combustion behaviors of pulverized coal, the conception of coal effective calorific value representing the actual thermal energy provided for blast furnace was proposed. A cost performance evaluation model of coal injection was built up for the optimal selection of various kinds of coal based on effective calorific value. The model contains two indicators: coal effective calorific value which has eight sub-indicators and coal injection cost which includes four sub-indicators. In addition, the calculation principle and application of cost performance evaluation model in a Chinese large-scale iron and steel company were comprehensively introduced. The evaluation results finally confirm that this novel model is of great significance to the optimal selection of blast furnace pulverized coal. 展开更多
关键词 blast furnace pulverized coal injection effective calorific value cost performance evaluation model
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Accuracy improvement of quantitative analysis of calorific value of coal by combining support vector machine and partial least square methods in laser-induced breakdown spectroscopy 被引量:2
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作者 Xiongwei LI Yang YANG +2 位作者 Gengda LI Baowei CHEN Wensen HU 《Plasma Science and Technology》 SCIE EI CAS CSCD 2020年第7期105-109,共5页
Laser-induced breakdown spectroscopy(LIBS) is a potential technology for online coal property analysis,but successful quantitative measurement of calorific value using LIBS suffers from relatively low accuracy caused ... Laser-induced breakdown spectroscopy(LIBS) is a potential technology for online coal property analysis,but successful quantitative measurement of calorific value using LIBS suffers from relatively low accuracy caused by the matrix effect.To solve this problem,the support vector machine(SVM) and the partial least square(PLS) were combined to increase the measurement accuracy of calorific value in this study.The combination model utilized SVM to classify coal samples into two groups according to their volatile matter contents to reduce the matrix effect,and then applied PLS to establish calibration models for each sample group respectively.The proposed model was applied to the measurement of calorific values of 53 coal samples,showing that the proposed model could greatly increase accuracy of the measurement of calorific values.Compared with the traditional PLS method,the coefficient of determination(R2) was improved from 0.93 to 0.97,the root-mean-square error of prediction was reduced from 1.68 MJ kg-1 to1.08 MJ kg-1,and the average relative error was decreased from 6.7% to 3.93%,showing an overall improvement. 展开更多
关键词 accuracy improvement calorific value COAL PLS SVM LIBS
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Experiments on Ni/γ-Al_2O_3 catalyst for improving lower heating value of biomass gasification fuel gas via methanation 被引量:3
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作者 Dong Xinxin Jin Baosheng +1 位作者 Wang Yanyan Niu Miaomiao 《Journal of Southeast University(English Edition)》 EI CAS 2017年第4期448-456,共9页
Ni-based catalysts supported by γ-Al_2O_3 were prepared for improving the lower heating value( LHV) of biomass gasification fuel gas through methanation. Prior to the performance tests, the physico-chemical propertie... Ni-based catalysts supported by γ-Al_2O_3 were prepared for improving the lower heating value( LHV) of biomass gasification fuel gas through methanation. Prior to the performance tests, the physico-chemical properties of the catalyst samples were characterized by N_2 isothermal adsorption/desorption, X-ray diffraction( XRD) and a scanning electron microscope( SEM). Afterwards, a series of experiments were carried out to investigate the catalytic performance and the results showthat catalysts with 15% and20% Ni loadings have better methanation catalytic effect than those with 5% and 10% Ni loadings in terms of elevating the LHV of biomass gasification fuel gas. M oreover, controllable influential factors such as the reaction temperature, the H_2/CO ratio and the water content occupy an important position in the methanation of biomass gasification fuel gas. 15 Ni/γ-Al_2O_3 and 20 Ni/γ-Al_2O_3 catalysts have a higher CO conversion and CH_4 selectivity at 350 ℃ and the LHV of biomass gasification fuel gas can be largely increased by 34. 3 % at 350 ℃. Higher H_2/CO ratio and a lower water content are more beneficial for improving the LHV of biomass gasification fuel gas when considering the combination of both CO conversion and CH_4 selectivity. This is due to the fact that a higher H_2/CO ratio and lower water content can increase the extent of the methanation reaction. 展开更多
关键词 N i-based catalyst METHANATION BIOMASS gasification fuel gas low er heating value
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An Experimental Determination of Gross Calorific Value of Different Agroforestry Species and Bio-Based Industry Residues 被引量:1
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作者 Ioannis Gravalos Panagiotis Xyradakis +3 位作者 Dimitrios Kateris Theodoros Gialamas Dimitrios Bartzialis Kyriakos Giannoulis 《Natural Resources》 2016年第1期57-68,共12页
Solid biomass fuels are useful and cost effective renewable energy source. The energy content of biomass is determined by its calorific value. The objective of this study was to determine experimentally the gross calo... Solid biomass fuels are useful and cost effective renewable energy source. The energy content of biomass is determined by its calorific value. The objective of this study was to determine experimentally the gross calorific value (GCV) of different agroforestry species and bio-based industry residues that could be used by: a) companies specialized in processing raw biomass solid biofuel production, b) small-scale consumers (households, medium-sized residential buildings, etc.). The fuel samples used were from agricultural residues and wastes (rice husks, apricot kernels, olive pits, sunflower husks, cotton stems, etc.), energy crops and wetland herbs (cardoon, switchgrass, common reed, narrow-leaf cattail), and forest residues (populus, fagus, pinus). The GCV of the bio-mass samples was experimentally determined based on CEN/TS 14918:2005, and an oxygen bomb calorimeter was used (Model C5000 Adiabatic Calorimeter, IKA?-Werke, Staufen, Germany). The GCV of different agroforestry species and residues ranges from 14.3 - 25.4 MJ?kg<sup>–</sup>1. The highest GCV was obtained by seeds and kernels due to higher unit mass and higher lipid content. Pinus sylvestris with moisture content 24.59% obtained the lowest GCV (13.973 MJ?kg<sup>–</sup>1). 展开更多
关键词 Gross calorific value Bomb Calorimeter BIOMASS BIOENERGY Agroforestry Residues
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Dynamic monitoring of menopause hormone therapy and defining the cut-off value of endometrial thickness during uterine bleeding 被引量:3
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作者 Qiu Sheng Jun Yang +1 位作者 Qiaoling Zhao Fen Li 《The Journal of Biomedical Research》 CAS CSCD 2016年第3期191-196,共6页
The aim of this study was to evaluate the effects of low-dose tibolone therapy on ovarian area, uterine volume and endometrial thickness, and define the cut-off value of endometrial thickness for curettage during uter... The aim of this study was to evaluate the effects of low-dose tibolone therapy on ovarian area, uterine volume and endometrial thickness, and define the cut-off value of endometrial thickness for curettage during uterine bleeding. We followed 619 postmenopausal women, aged 40-60 years, for two years. There were 301 subjects in the low-dose tibolone treatment group and 318 subjects in the control group. The ovarian area, uterine volume and endometrial thickness in all participants were measured by transvaginal ultrasound prior to, one and two years post enrollment, respectively. Endometrial specimens were collected from all subjects with abnormal uterine bleeding during the follow-up period. We found that the uterine volume in the treatment group was greater than that in the control group, and the difference was significant (P〈0.05), but there were no significant differences in ovarian area and endometrial thickness between the two groups (P〉0.05). When the cut-off value for endometrial thickness was 7.35 ram, the sensitivity and specificity were 100% and 79.07%, respectively, and 85.71% and 93.02% when 7.55 mm was set as the cut-offduring tibolone therapy. The results indicate that low-dose tibolone therapy may postpone uterine atrophy and the cut-off value of endometrial thickness may be appropriately adjusted for curettage. 展开更多
关键词 low-dose tibolone ovarian area uterine volume ENDOMETRIUM dynamic monitoring cut-off value
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Operation Mechanism of Farmers' Professional Cooperatives from the Point of Low-Carbon Agricultural Products 被引量:1
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作者 HUANG Lei,CHENG Yu-gui Nanchang Hangkong University,Jiangxi 330063,China 《Asian Agricultural Research》 2012年第3期46-50,共5页
We firstly take a look at internal logic of cluster development of low-carbon agricultural products.In combination with operation features of farmers' professional cooperatives and actual requirements for cluster ... We firstly take a look at internal logic of cluster development of low-carbon agricultural products.In combination with operation features of farmers' professional cooperatives and actual requirements for cluster development of low-carbon agricultural products;we elaborate establishing benefit allocation mechanism,bearing education and training functions,forming low-carbon value,building low-carbon identification system,as well as realizing low-carbon value.According to these situations,we systematically analyze operation mechanism of farmers' professional cooperatives suitable for cluster development of low-carbon agricultural products.To promote cluster development of low-carbon agricultural products,we put forward following suggestions,including government guidance and encouragement,social acceptance and active cooperation,and integration into global low-carbon development system to share benefit of low-carbon development. 展开更多
关键词 CLUSTER of low-carbon AGRICULTURAL products FARMER
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Effect of stabilizing elements Nb and Ti on the microstructure and properties of low carbon ferritic stainless steel 被引量:2
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作者 ZHANG Xin SUN Quanshe +1 位作者 ZHOU En DU Wei 《Baosteel Technical Research》 CAS 2010年第1期30-34,共5页
The effect of stabilizing elements, such as Nb and Ti, on the microstructure and properties of low carbon ferritic stainless steel (FSS) has been investigated. The results of the Thermo-calc simulation have shown th... The effect of stabilizing elements, such as Nb and Ti, on the microstructure and properties of low carbon ferritic stainless steel (FSS) has been investigated. The results of the Thermo-calc simulation have shown that the interstitial elements, such as C and N, may be completely stabilized by the addition of Nb and Ti. With the increase of Nb and Ti contents ,the α + γ two phases gradually transfer to a single α-phase under a high temperature condition ,and the content of the carbide M23 C6 gradually decreases. The microstructure has indicated that the combined addition of Nb and Ti can promote the recrystallization of the band structure and form more uniform equiaxed grains. Also, with the increase of Nb and Ti contents,the elongation, the r-value and the corrosion resistance of cold-rolled and annealed sheets are improved prominently. In comparison with the effect of Ti ,the addition of Nb is more beneficial to the increase of r-value and the corrosion resistance. 展开更多
关键词 low carbon ferritic stainless steel stabilizing element R-value corrosion resistance
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Effects of Imidapril on Venous Blood Gas Values in Broiler Chickens Exposed to Low Ambient Temperature
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作者 Xueqin HAO Meng LI +2 位作者 Shouyan ZHANG Yongshu WANG Tongwen SUN 《Agricultural Science & Technology》 CAS 2013年第7期1002-1004,共3页
ObjectiveThis study was designed to evaluate the effects of imidapril on blood gas parameters in broiler chickens. MethodTwenty-four chickens were randomly divided into three groups (n=8), control group, low temperatu... ObjectiveThis study was designed to evaluate the effects of imidapril on blood gas parameters in broiler chickens. MethodTwenty-four chickens were randomly divided into three groups (n=8), control group, low temperature group and imidapril group. Chickens in low temperature group and imidapril group were exposed to low ambient temperature (12-18 ℃) from age at 14 d to 45 d, whereas the control group was exposed to 24-30 ℃; chickens in imidapril group were gavaged with imidapril (3 mg/kg) once daily for 30 d. At age of 45 d, blood was taken from wing vein and blood gas parameters were evaluated by blood gas analyzer in Luoyang Central Hospital Affiliated to Zhengzhou University. ResultImidapril significantly increased hematocrit (HCT) and total hemoglobin content (T HBC ) and blood Na concentration in broiler chickens exposed to low ambient temperature. No significant differences were observed in pH, P CO 2 , P O 2 , K + , Ca 2+ , HCO 3-, HCO 3std , T CO 2 , BE and SO 2c . ConclusionImidapril increases hematocrit, total hemoglobin content and blood Na + concentration in chickens exposed to low ambient temperature. 展开更多
关键词 IMIDAPRIL Blood gas value Broiler chicken low ambient temperature
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The coupling of dynamics and permeability in the hydrocarbon accumulation period controls the oil-bearing potential of low permeability reservoirs:a case study of the low permeability turbidite reservoirs in the middle part of the third member of Shahejie 被引量:10
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作者 Tian Yang Ying-Chang Cao +4 位作者 Yan-Zhong Wang Henrik Friis Beyene Girma Haile Ke-Lai Xi Hui-Na Zhang 《Petroleum Science》 SCIE CAS CSCD 2016年第2期204-224,共21页
The relationships between permeability and dynamics in hydrocarbon accumulation determine oil- bearing potential (the potential oil charge) of low perme- ability reservoirs. The evolution of porosity and permeabilit... The relationships between permeability and dynamics in hydrocarbon accumulation determine oil- bearing potential (the potential oil charge) of low perme- ability reservoirs. The evolution of porosity and permeability of low permeability turbidite reservoirs of the middle part of the third member of the Shahejie Formation in the Dongying Sag has been investigated by detailed core descriptions, thin section analyses, fluid inclusion analyses, carbon and oxygen isotope analyses, mercury injection, porosity and permeability testing, and basin modeling. The cutoff values for the permeability of the reservoirs in the accumulation period were calculated after detailing the accumulation dynamics and reservoir pore structures, then the distribution pattern of the oil-bearing potential of reservoirs controlled by the matching relationship between dynamics and permeability during the accumulation period were summarized. On the basis of the observed diagenetic features and with regard to the paragenetic sequences, the reservoirs can be subdivided into four types of diagenetic facies. The reservoirs experienced two periods of hydro- carbon accumulation. In the early accumulation period, the reservoirs except for diagenetic facies A had middle to high permeability ranging from 10 × 10-3 gm2 to 4207 × 10-3 lain2. In the later accumulation period, the reservoirs except for diagenetic facies C had low permeability ranging from 0.015 × 10-3 gm2 to 62× 10-3 -3m2. In the early accumulation period, the fluid pressure increased by the hydrocarbon generation was 1.4-11.3 MPa with an average value of 5.1 MPa, and a surplus pressure of 1.8-12.6 MPa with an average value of 6.3 MPa. In the later accumulation period, the fluid pressure increased by the hydrocarbon generation process was 0.7-12.7 MPa with an average value of 5.36 MPa and a surplus pressure of 1.3-16.2 MPa with an average value of 6.5 MPa. Even though different types of reservoirs exist, all can form hydrocarbon accumulations in the early accumulation per- iod. Such types of reservoirs can form hydrocarbon accumulation with high accumulation dynamics; however, reservoirs with diagenetic facies A and diagenetic facies B do not develop accumulation conditions with low accumu- lation dynamics in the late accumulation period for very low permeability. At more than 3000 m burial depth, a larger proportion of turbidite reservoirs are oil charged due to the proximity to the source rock, Also at these depths, lenticular sand bodies can accumulate hydrocarbons. At shallower depths, only the reservoirs with oil-source fault development can accumulate hydrocarbons. For flat surfaces, hydrocarbons have always been accumulated in the reservoirs around the oil-source faults and areas near the center of subsags with high accumulation dynamics. 展开更多
关键词 Reservoir porosity and permeabilityevolution Accumulation dynamics Cutoff-values ofpermeability in the accumulation period Oil-bearingpotential low permeability reservoir the third memberof the Shahejie Formation Dongying Sag
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