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Fundamental Research on Comprehensive Exploitation and Utilization of Paragenetic Fluorite in Bayan Obo deposit of Inner Mongolia,China
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作者 Wenling Xuan,Jianyong Liu,Chengzhi Sun,Zengyu Zhao 1.School of Earth and Space Sciences,Peking University,Beijing 100081,China. 2.Bayan Obo Iron Mining,Baotou Iron & Steel Co.Ltd,Baotou 014000,China 3.Institute of Reconnaissance & Survey,Baotou Iron & Steel Co.Ltd,Baotou 014000,China 《地学前缘》 EI CAS CSCD 北大核心 2009年第S1期178-178,共1页
Bayan Obo deposit in Inner Mongolia,China is not only the largest Iron-LREE-niobium deposit known in the world but also a giant fluorite deposit.Banded and streaky fluorite-rich REE-iron ores,bastnasiteapatite -pyroxe... Bayan Obo deposit in Inner Mongolia,China is not only the largest Iron-LREE-niobium deposit known in the world but also a giant fluorite deposit.Banded and streaky fluorite-rich REE-iron ores,bastnasiteapatite -pyroxene-fluorite ores,high-Fe,REEs,and fluorite ores,monazite(bastnaesite)-fluorite(low-Fe, high REE) ores etc.are widely disseminated in the Main and the East ore bodies.In 1985,proven 展开更多
关键词 Bayan OBO DEPOSIT paragenetic FLUORITE COMPREHENSIVE exploitation and utilization location-quantity-quality model industrial index
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Performance and Nutrient Utilization of Layers Fed Diet Supplemented with Microbial Phytase and Cellulase 被引量:2
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作者 WANG Li juan,SHAN An shan,SONG Jin cai (Animal Nutrition Institute,Northeast Agricultural University,Harbin Heilongjiang,150030,PRC) 《Journal of Northeast Agricultural University(English Edition)》 CAS 2003年第1期33-39,共7页
A 31 week feeding trial was conducted to investigated the effects of dietary supplementation of microbial phytase and cellulase on performance,nutrients utilization and tibia quality of laying hens fed maize and soyb... A 31 week feeding trial was conducted to investigated the effects of dietary supplementation of microbial phytase and cellulase on performance,nutrients utilization and tibia quality of laying hens fed maize and soybean meal diets.192 18 week old Hisex layers were used in the trial A 2×2×2 factorial design was used in the experiment with three factors of two levels each:0 38% and 0 16% of dietary non phytate P(nP).0 and 300 U·kg -1 of phytase (Ph),and 0 and 0 10% of cellulase (Ce).The results showed that supplementation of 300 U·kg -1 phytase significantly improved utilization of dietary crude ash,CP,Ca,total P and copper (P<0 05),and improved tibia breaking strength (P<0 05).No effect of phytase on performance was observed.Addition of 0 10% cellulase decreased feed intake (P<0 05),increased utilization of CF (P<0 05) and Ca(P<0 01),and decreased total tibia ash weight (P<0 05).300 U·kg -1 phytase and 0 10% cellulase exhibited obvious positive interactions to enhance utilization of dietary phytic P and copper (P<0 05).0 16% nP did not reduce performance of the layers,but improved egg shell quality at 20 wks,increased utilization of dietary total P,phytic P and Copper (P<0 01),decreased utilization of dietary CP,increased tibia breaking strength and Ca,Mn contents of tibia(P<0 01) 展开更多
关键词 microbial phytase CELLULASE LAYERS PERFORMANCE utilization of nutrientss
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Dynamic bandwidth allocation algorithm for full-band utilization 被引量:1
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作者 Han Guodong Wang Hui Wu Jiangxing 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2006年第1期223-229,共7页
To improve and optimize the bandwidth utilization for multi-service packet transporting system, a kind of Dynamic Full Bandwidth Utilized (DFBU) allocation algorithm allowing a single link to use far beyond its fair... To improve and optimize the bandwidth utilization for multi-service packet transporting system, a kind of Dynamic Full Bandwidth Utilized (DFBU) allocation algorithm allowing a single link to use far beyond its fair share bandwidth is presented. Three important parameters as the bound on max and minimum bandwidth, the maximum packet delay and the minimum bandwidth utilization are discussed and analyzed. Results of experiments show that the DFBU-algorithm is capable of making a single link in the system use all the spare bandwidth (up to full-bandwidth) while the performance of fairness and QoS requirement is still guaranteed. 展开更多
关键词 full-band utilize dynamic allocation algorithm FAIRNESS bandwidth utilization
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Science Research and Utilization Planning of China’s Space Station in Operation Period 2022–2032 被引量:6
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作者 GU Yidong GAO Ming ZHAO Guangheng 《空间科学学报》 CAS CSCD 北大核心 2020年第5期609-614,共6页
The core module of China’s Space Station(CSS)is scheduled to be launched around the end of 2020,and the experimental module I and II will be launched in the next two years.After on-orbit constructions,CSS will be tra... The core module of China’s Space Station(CSS)is scheduled to be launched around the end of 2020,and the experimental module I and II will be launched in the next two years.After on-orbit constructions,CSS will be transferred into an operation period over 10 years(2022–2032 and beyond)to continuously implement space science missions.At present,based on the project selection and research work in the ground development period of CSS,China is systematically making a utilization mission planning for the operation period,which focuses on the fields of aerospace medicine and human research,space life science and biotechnology,microgravity fluid physics,combustion science,materials science,fundamental physics,space astronomy and astrophysics,Earth science,space physics and space environment,space application technology,etc.In combination with the latest development trend of space science and technology,China will continue to update planning for science research and technology development,carry out project cultivation,payload R&D,and upgrade onboard and ground experiment supporting systems to achieve greater comprehensive benefits in science,technology,economy,and society。 展开更多
关键词 China’s space station utilization PLANNING EXPERIMENT
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The Comprehensive Utilization and Purified Research on Kaolin Ores in Huichang
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作者 WU Caibin SHI Guiming 《矿物学报》 CAS CSCD 北大核心 2013年第S1期109-109,共1页
Kaolin ores in Huichang contains these minerals of quartz sand, kaolin, mica and feldspars. In order to recover these valuable resources, some experiments of screening, classification, magnetic separation, grinding an... Kaolin ores in Huichang contains these minerals of quartz sand, kaolin, mica and feldspars. In order to recover these valuable resources, some experiments of screening, classification, magnetic separation, grinding and flotation are carried out on the basis of the kaolin ore properties. The test results indicate that quartz sand concentrate can be directly obtained when vibrating screen size used is 10 meshes. Materials that are smaller than the screen hole are injected to hydraulic cyclones which controlling classification size is 325 meshes; kaolin concentrate containing above 33.70% Al2O3 and 0.37% Fe2O3 can be well beneficiated from the overflow through magnetic separation with one stage rougher and cleaner to remove iron. On the other hand, the hydrocyclone spigot flow to grinding and flotation with one stage rougher and two scavengers, mica and feldspars concentrate can be beneficiated in sequence. Therefore, these valuable minerals of kaolin ores can be realized comprehensive utilization. 展开更多
关键词 KAOLIN ORES magnetic SEPARATION FLOTATION COMPREHENSIVE utilization
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Genetics Research and Advance on Development and Utilization of Wild Boars
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作者 LIU Chunlong LIU Di LI Zhongqiu 《Journal of Northeast Agricultural University(English Edition)》 CAS 2011年第3期83-87,共5页
Wild boar is one of the most important beast resources. It plays an important role in the maintenance of biological diversity. The genetic resources of wild boar can not only protect the genetic resources, but also im... Wild boar is one of the most important beast resources. It plays an important role in the maintenance of biological diversity. The genetic resources of wild boar can not only protect the genetic resources, but also improve the formation of new breeds in pigs. This paper summarized the advance on the main biological characteristics of wild boars, evolutionary origin between wild boars and domesticated pigs, and development and utilization of wild boars aimed to provide further insight into wild boar's genetic research and its resource protection. 展开更多
关键词 wild boar biological characteristics GENETICS development and utilization
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Carrying Capacity and Utilization Potential Analysis of Groundwater Resources in Semiarid District in Heilongjiang Province
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作者 Bai Xue-feng Xu Shu-qin Qi ying 《Journal of Northeast Agricultural University(English Edition)》 CAS 2013年第2期77-81,共5页
Irrigation water became the limiting factor to the persistent improvement of grain production. Based on the data from Gannan County, a semiarid area in the west of Heilongjiang Province, the present situation of the d... Irrigation water became the limiting factor to the persistent improvement of grain production. Based on the data from Gannan County, a semiarid area in the west of Heilongjiang Province, the present situation of the development and utilization of water resources and the suitable water saving irrigation mode were analyzed by using SPA model, which was significant to the efficient and rational utilization of water resources and the improvement of agriculture productivity. The result showed that the model could be applied well to the assessment of development and utilization of water resources and the multi-project optimal selection. Through calculation, it could be found that the utilization of water resources in Gannan County was still in the primary stage, and the integration technology of the optimized water saving irrigation should be combined to support the sustainable development of agriculture in the semiarid area. 展开更多
关键词 semiarid district groundwater carrying capacity utilization potential Set Pair analysis
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Evaluation on Diseases Resistance of Cotton Material and Its Utilization
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作者 ZENG Hua-lan,HE Lian,YE Peng-sheng,ZHANG Yu,WEI Shu-gu(Industrial Crops Research Institute,Sichuan Academy of Agricultural Science,Jianyang 641400,Sichuan,China) 《棉花学报》 CSCD 北大核心 2008年第S1期102-,共1页
Fusarium wilt and Verticillium wilt are important worldwide fungal diseases on cotton that cause damage to yield and quality.The pathogens survive in soil as microsclerotia for many years,and
关键词 Evaluation on Diseases Resistance of Cotton Material and Its utilization RVH
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Quercetin Increased Protein Utilization and Decreased Nitrogen Excretion in Broilers by Activating TOR Signaling Pathway
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作者 Xiao Feng-lin Mao Yan-jun +4 位作者 Ying Lin-lin Wang Mi Wang Shan-shan Wang Bo Li Yao 《Journal of Northeast Agricultural University(English Edition)》 CAS 2021年第2期77-87,共11页
The study was conducted to investigate the effect and mechanism of dietary quercetin supplementation on protein utilization of Arbor Acres(AA)broilers.A total of 2401-day-old AA broilers were randomly allocated to fou... The study was conducted to investigate the effect and mechanism of dietary quercetin supplementation on protein utilization of Arbor Acres(AA)broilers.A total of 2401-day-old AA broilers were randomly allocated to four treatments with six replicates,comprising 10 broilers each replicate(60 broilers per treatment).Birds were fed either a corn-soybean meal basal diet without quercetin(control)or a basal diet supplemented with 0.2,0.4 or 0.6 g of quercetin per kg feed,and the trial lasted 42 days.Dietary quercetin supplementation tended to increase the apparent metabolic rate of protein(p=0.076)and the content of serum albumin(p=0.062)in AA broilers.Compared with the control,dietary quercetin supplementation increased the contents of protein in breast muscle(p<0.05)and in thigh muscle(p=0.053).In addition,quercetin up-regulated mRNA expression of insulin-like growth factor 1(IGF-1),phosphatidylinositol 3-kinase(PI3K),target of rapamycin(TOR),ribosomal protein S6 kinase 1(S6K1),eukaryotic translation initiation factor 4E(eIF4E),eukaryotic translation initiation factor 4G(eIF4G),eukaryotic elongation factor 2(eEF2)and eukaryotic translation initiation factor 4B(eIF4B)genes and down-regulated mRNA expression of eukaryotic elongation factor 2 kinase(eEF2K)and eukaryotic initiation factor 4E binding protein1(4E-BP1)genes in breast muscle,thigh muscle and liver of AA broilers(p<0.05).The present results suggested that dietary quercetin supplementation enhanced protein utilization in broilers by activating TOR signaling pathway. 展开更多
关键词 Arbor Acres broiler phosphatidylinositol 3-kinase protein utilization gene expression target of rapamycin signaling pathway
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Collection,Evaluation,and Utilization of Cotton Germplasm in China
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作者 DU Xiong-ming,ZHOU Zhong-li,SUN Jun-Ling,PAN Zhao-e,JIA Yin-hua(Cotton Research Institute,Chinese Academy of Agricultural Sciences Key Laboratory of Cotton Genetic Improvement,Ministry of Agriculture,Anyang,Henan 455000,China) 《棉花学报》 CSCD 北大核心 2008年第S1期75-,共1页
A total of 8193 accessions,including 6822 Gossypium hirsutum,350 G.hirsutum race(sub-species),385 of G.barbadense,378 of G.arboreum,17 of G.herbaceum and 41 wild species,of
关键词 Collection Evaluation and utilization of Cotton Germplasm in China
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Resource utilization of hazardous gypsum sludge in oxidation smelting of lead concentrate
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作者 PAN Zu-chao RUAN Bo-wen +2 位作者 JIAO Fen QIN Wen-qing LIU Wei 《Journal of Central South University》 SCIE EI CAS CSCD 2024年第9期3103-3118,共16页
Gypsum sludge,a hazardous waste generated by the non-ferrous smelting industry,presents a significant challenge for disposal and utilization.To investigate the feasibility of substituting gypsum sludge for limestone a... Gypsum sludge,a hazardous waste generated by the non-ferrous smelting industry,presents a significant challenge for disposal and utilization.To investigate the feasibility of substituting gypsum sludge for limestone as a flux for smelting,the effects of calcium sulfate(CaSO_(4))and smelting conditions on oxygen-rich smelting of lead concentrate were studied.The interaction between CaSO_(4)and sulfides facilitates the conversion of CaSO_(4)into CaO,which is crucial for slag formation.The order of the influence of sulfide minerals on the conversion of CaSO_(4)is pyrite>sphalerite>galena.When using gypsum sludge exclusively as the calcium source,under optimal conditions with a CaO/SiO_(2)mass ratio of 0.8,an FeO/SiO_(2)mass ratio of 1.2,a melting temperature of 1150℃,an oxygen flow rate of 1.3 L/min,the recovery rates of Pb and Zn in the lead-rich slag reached 85.01%and 95.69%,respectively,with a sulfur content of 2.65 wt%.The As content in the smelting slag obtained by reduction smelting was 0.02 wt%.Resource utilization of gypsum sludge in lead smelting is a feasible method. 展开更多
关键词 gypsum sludge calcium sulfate resource utilization SMELTING
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Improving energy utilization efficiency of electrical discharge milling in titanium alloys machining 被引量:3
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作者 郭成波 韦东波 狄士春 《Journal of Central South University》 SCIE EI CAS CSCD 2016年第10期2550-2557,共8页
Electrical discharge milling(ED-milling) can be a good choice for titanium alloys machining and it was proven that its machining efficiency can be improved to compete with mechanical cutting. In order to improve energ... Electrical discharge milling(ED-milling) can be a good choice for titanium alloys machining and it was proven that its machining efficiency can be improved to compete with mechanical cutting. In order to improve energy utilization efficiency of ED-milling process, unstable arc discharge and stable arc discharge combined with normal discharge were implemented for material removal by adjusting servo control strategy. The influence of electrode rotating speed and dielectric flushing pressure on machining performance was investigated by experiments. It was found that the rotating of electrode could move the position of discharge plasma channel, and high pressure flushing could wash melted debris out the discharge gap effectively. Both electrode rotating motion and high pressure flushing are contributed to the improvement of machining efficiency. 展开更多
关键词 electrical discharge milling electrode rotating dielectric flushing energy utilization efficiency material removal rate tool electrode wearing rate
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New technique of comprehensive utilization of spent Al_2O_3-based catalyst 被引量:3
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作者 冯其明 陈云 +3 位作者 邵延海 张国范 欧乐明 卢毅屏 《Journal of Central South University of Technology》 EI 2006年第2期151-155,共5页
A new technology was developed to recover multiple valuable elements from the spent Al2O3-based catalyst by X-ray phase analysis and exploratory experiments. The experimental results show that in the condition of roas... A new technology was developed to recover multiple valuable elements from the spent Al2O3-based catalyst by X-ray phase analysis and exploratory experiments. The experimental results show that in the condition of roasting temperature of 750℃ and roasting time of 30 min, molar ratio of Na2O to Al2O3 of 1.2, the leaching rates of alumina, vanadium and molybdenum in the spent catalyst are 97.2%, 95.8% and 98.9%, respectively. Vanadium and molybdenum in sodium aluminate solution can be recovered by precipitators A and B, and the precipitation rates of vanadium and molybdenum are 94.8% and 92.6%. Al(OH)3 was prepared from sodium aluminate solution in the carbonation decomposition process, and the purity of Al2O3 is 99.9% after calcination, the recovery of alumina reaches 90.6% in the whole process; the Ni-Co concentrate was leached by sulfuric acid, a nickel recovery of 98.2% and cobalt recovery over 98.5% can be obtained under the experimental condition of 30% H2SO4, 80℃, reaction time 4 h, mass ratio of liquid to solid 8, stirring rate 800r/min. 展开更多
关键词 spent Al2O3-based catalyst vanadium molybdenum comprehensive utilization roasting with sodium leaching rate
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The Utilization of HB-red Flower in Hybrid Cotton Breeding 被引量:2
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作者 WANG Liu-ming,WANG Jia-bao(Shandong Cotton Research Center,Ji’nan,Shandong 250100,China) 《棉花学报》 CSCD 北大核心 2008年第S1期86-,共1页
The HB-red flower trait came from the filial generation of the interspecific cross of upland cotton(Gossypium hirsutum L.) and G.bickii.It exhibits pink petals and filaments,with a large
关键词 HB The utilization of HB-red Flower in Hybrid Cotton Breeding
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Preliminary Discussion on Comprehensive Utilization of Tailings
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作者 WANG Fudong ZHU Xiaoqing +4 位作者 WANG Zhonggang HAN Tao LI Zengsheng SUN Xiaohui LING Kunyao 《矿物学报》 CAS CSCD 北大核心 2013年第S1期97-98,共2页
Tailings produced in a concentration plant are the discharge of solid wastes after grinding ore into size and selecting useful components in the specific economic and technological condition. According to statistics, ... Tailings produced in a concentration plant are the discharge of solid wastes after grinding ore into size and selecting useful components in the specific economic and technological condition. According to statistics, for the mining of metal ore, non-metallic ore, coal, clay, etc, the production of tailings of the world is up to 100 million tons per year. The number of existing tailing piles is 12718 in China, of which the construction ones are 1526, accounting for 12% of the total, and the closed tailing piles are 1024, accounting for 8%. As of 2007, the national total tailings accumulation is 8.046 billion tons. The non-ferrous metal mining is one of the largest discharge of solid wastes industries because of its low comprehensive recovery rate. For example, the beneficiation and recovery rate of non-ferrous metal mine is from 50% to 60% in China, which is lower 10% to 15% than developed countries, and the associated non-ferrous metal recovery rate is 40%, which is lower 20% than developed countries. On the utilization of duns, Poland is 90% to 100%, United States, Australia, France, Canada, Belgium and other countries followed, while China is only about 20%. The utilization of fly ash is to 100% in Japan and Denmark, France is 65%, UK is 55%, and China is just 45%. Quantities of waste rock, waste slag, and waste water have occupied land, destructed vegetation, deteriorated the soil and water quality, and caused land subsidence, landslides, mud-flow and other geological disasters. Therefore, the comprehensive utilization of resources is the right choice of mining sustainable development, environment protection, resource conservation, economic and social development. 展开更多
关键词 TAILINGS COMPREHENSIVE utilization non-ferrous metal MINING
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Utilization of Cotton DNA Markers in Cotton Breeding
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作者 CANTRELL Roy G 《棉花学报》 CSCD 北大核心 2008年第S1期15-,共1页
Informative,portable,and efficient DNA markers have the potential to accelerate genetic gain in cotton breeding.Discovery and widespread application of DNA markers to cotton has
关键词 DNA utilization of Cotton DNA Markers in Cotton Breeding
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Relative Efficiency Evaluation on Water Resource Utilization 被引量:3
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作者 MA Ying 《Journal of Northeast Agricultural University(English Edition)》 CAS 2011年第3期60-64,共5页
Water resource allocation was defined as an input-output question in this paper, and a preliminary input-output index system was set up. Then GEM (group eigenvalue method)-MAUE (multi-attribute utility theory) mod... Water resource allocation was defined as an input-output question in this paper, and a preliminary input-output index system was set up. Then GEM (group eigenvalue method)-MAUE (multi-attribute utility theory) model was applied to evaluate relative efficiency of water resource allocation plans. This model determined weights of indicators by GEM, and assessed the allocation schemes by MAUE. Compared with DEA (Data Envelopment Analysis) or ANN (Artificial Neural Networks), the mode was more applicable in some cases where decision-makers had preference for certain indicators 展开更多
关键词 water resource allocation group eigenvalue method multi-attribute utility theory EVALUATION
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Deep Utilization of Exhaust Heat and Comprehensive Optimization of Tail Heating Surfaces for Utility Boilers
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作者 Xu Gang XU Cheng +2 位作者 YANG Yongping HUANG Shengwei ZHANG Kai 《中国电机工程学报》 EI CSCD 北大核心 2013年第14期I0001-I0016,共16页
In common,the waste heat of the flue gas is recovered and utilized to heat the low temperature feedwater by installing the low temperature economizer(LTE),which can save the steam extracted from the steam turbine and ... In common,the waste heat of the flue gas is recovered and utilized to heat the low temperature feedwater by installing the low temperature economizer(LTE),which can save the steam extracted from the steam turbine and then increase the unit output.However,restricted by the low temperature of waste flue gas,the energy-saving efect is inconspicuous.Based on the common waste heat utilization system of the flue gas. 展开更多
关键词 utility boiler tail heating surface comprehensive optimization waste heat recovery low temperature economizer
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Utilization of α-olefins obtained by pyrolysis of waste high density polyethylene to synthesize α-olefin-succinic-anhydride based cold flow improvers
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作者 Norbert MISKOLCZI Richard SAGI László BARTHA Lívia FORCEK 《燃料化学学报》 EI CAS CSCD 北大核心 2009年第3期302-310,共9页
浪费聚合物热分解获得的石蜡富人烃部分的利用的一条新线路被调查。-olefin-succinic-anhydride 基于中介倒点镇静剂添加剂因为柴油被综合,在哪个反应需要的石蜡被废物的热分解获得高密度的聚乙烯(HDPE ) 。石蜡的部分被塑料废物的de... 浪费聚合物热分解获得的石蜡富人烃部分的利用的一条新线路被调查。-olefin-succinic-anhydride 基于中介倒点镇静剂添加剂因为柴油被综合,在哪个反应需要的石蜡被废物的热分解获得高密度的聚乙烯(HDPE ) 。石蜡的部分被塑料废物的de聚合在 500 滓鲥?在一个试管反应堆生产???????????????????????禧?????迋????骤??????吗鲥??????禧哉????嫪????滓?????篤?廯??????可??????????????裍??妢???????臙???????蚨?蚨?? 展开更多
关键词 添加剂 石油炼制 成份 燃料化学 高温分解
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Exploitation of Wild Flowers and the Sustainable Development of Flowers Industry in China 被引量:4
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作者 HONG Li PANG Songling ZHUO Lihuan 《Journal of Northeast Agricultural University(English Edition)》 CAS 2008年第2期76-79,共4页
This article introduced the new methods on the research of the wild flowers and plants idioplasmic resources, elaborated the introduction and domestication and exploitation of wild flowers and plants idioplasmatic res... This article introduced the new methods on the research of the wild flowers and plants idioplasmic resources, elaborated the introduction and domestication and exploitation of wild flowers and plants idioplasmatic resources and the sustainable development of flowers and plants industry in China, and put forward some proposals on the existing question and the prospects for the development. 展开更多
关键词 wild flowers and plants development and utilization flowers and plants industry sustainable development
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