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天源
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作者 汝百乐 《花木盆景(下半月)》 2010年第1期57-57,共1页
“日月之行,若出其中;星汉灿烂,若出其里。”深邃的夜空,繁星闪烁,无数的繁星在无始无终的轮回中,划出了一道道玄妙优美的轨迹。佛说,顽石可以说法。道家云,大音希声,大象无形。一块小小的石头也蕴含着常人一生也难参悟到的真理。
关键词 《天源》 私人收藏 卷纹石 李明
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Fenlong Cultivation-the Fourth Set of Farming Methods Invented in China 被引量:18
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作者 韦本辉 《Agricultural Science & Technology》 CAS 2017年第11期2045-2048,2052,共5页
The basic theory and effect of the new farming method of "Fenlong" cultivation which has been included in the main extension technology of Ministry of Agriculture of the People's Republic of China is fully illustra... The basic theory and effect of the new farming method of "Fenlong" cultivation which has been included in the main extension technology of Ministry of Agriculture of the People's Republic of China is fully illustrated for the first time, and it is the fourth set (generation) of farming modes and methods following manpower, animal and mechanical (tractor) farming. It follows the natural law to achieve soil activation, water saving, oxygen increase, warming and desalination through the active use of natural resources like soil, rainfall and solar energy, thereby promoting a new round of natural agricultural production and quality improvement and water con- servation, which has crop yield increase by 10%-30%, quality improvement of 5%, natural precipitation retaining increase by100%. The characteristics and mechanism are the use of spiral drill for one-time completion of the land preparation by drilling vertically to 30-50 cm of soil layer through high speed peeling. After instant high temperature and many fierce impacts, mechanical frictions, it could achieve the multiplication of the number of loose soil, soil physical modification and expansion of the soil nutrients, reservoirs, oxygen, microorganisms ("Four pools"). Fenlong cultivation can give birth to new farming culture and civilization, and it can achieve the physical "desalinized" transformation and utilization of saline soil. The formation of Fenlong green farming technology system makes it possible to invent the farming tools of "serf-propelled Fenlong machinery" that has got the patent, and it is the method for farmland (dry land, paddy field) Fenlong cultivation, saline-alkali soil smash-ridging cultivation and for the abundance of grass ecology on degraded grassland. The application of Fenlong "4+1" (arable, saline-alkali soil, grasslands, Sponge City+rivers) green development in China can achieve the "double safety" of food and living space. 展开更多
关键词 Fenlong cultivation The fourth set (generation) of new farming methods Activation and utilization of natural resources Improvement of production and quality Water conservation ecology
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Screening of Strains and Nutrition Sources for Culture of Armillariella mellea Rhizomoph Branch in Ganzi 被引量:1
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作者 谢学强 《Agricultural Science & Technology》 CAS 2016年第8期1909-1911,共3页
Based on the natural resources in Ganzi Tibetan Autonomous Prefecture, screening experiment of strains and nutrient sources for culture of Armillariella mellea rhizomoph branch was carried out with 3 strains of A. mel... Based on the natural resources in Ganzi Tibetan Autonomous Prefecture, screening experiment of strains and nutrient sources for culture of Armillariella mellea rhizomoph branch was carried out with 3 strains of A. mellea, 2 types of main nutrient sources and 3 kinds of auxiliary nutrient sources. Total 18 treatments were designed. The results showed that with the A. mellea strain separated from the tubers of wild Gastrodia elata BI. by tissue isolation as mother strain, the shrubs such as Prunus tatsienensis Batal and Quercus spinosa David ex Franch as the main nutrient sources, and the agricultural products such as corn and potato as the supplementary nutrient sources, the growth of A. mellea rhizomoph branch was best in bottle. 展开更多
关键词 Armillariella mellea Rhizomoph branch culture STRAIN Nutrient source Artificial cultivation of Gastrodia elata BI.
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Discussion on Green Development of Fenlong for Yield Increase, Quality Enhancing, Water Retaining and Multiple Use of Natural Resources 被引量:7
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作者 韦本辉 《Agricultural Science & Technology》 CAS 2017年第9期1631-1637,共7页
Fenlong green ecological agriculture technology (Fenlong technology), a new smash ridging farming method developed by Guangxi Academy of Agdcultural Sciences, has been elected as the recommended cultivation techniqu... Fenlong green ecological agriculture technology (Fenlong technology), a new smash ridging farming method developed by Guangxi Academy of Agdcultural Sciences, has been elected as the recommended cultivation technique by the Ministry of Agriculture of China. It replaces the traditional plowshare with spiral drill, and its tilth depth is twice deeper than that by tractor tilthing. It also extends soil nutrient, moisture, oxygen and microorganism, the so-called "Four pools". Soil nutrient, oxygen, microorganism, light and rainfall use ratio is increased by 10%-100%, creating a platform for natural increase of more than 10% of crop yield. Its application to over 20 kinds of crops in 21 provinces has proved that the yield increases 10-30% with quality enhancing 5% and double water retaining capacity but no more input. When the application area of Fenlong could reach 67 million hm2, the amount of fertilizer can be reduced by 40-50 billion kg, saving 120-150 billion Yuan. In this paper, we put forward the strategy of "4+1" (arable, saline-alkali soil, grasslands, Sponge City + rivers) green development in China, and deepened the Fenlong cultivated tilled layer from 16.5 cm to 35 cm for 67 million hm2 arable land, ridged 13.3 million hm2 of saline-alkali soil for 35 cm, and also 35 cm for 67 million hm2 degraded steppe, which could have the following 3 effects: first, the 147 million hm2 of land with Fenlong cultivation could increase loosing soil to 315.491 billion m3, in* creasing by 159.26% for 120 million hm2 of arable land with the average tilled layer of 16.5 cm, which has loosing soil of only 198.1 billion m3, that is, the space of the land increases 1.6 times. Second, every hectare of plowland could store up to 450 m3/hm2 of natural rainfall, and the unused 60 m3 of saline-alkali soil and grasslands could store water of 102 billion m3, showing an increase of over 88.89% for the current plowland storage of 54 billion m3 at now, that is, double the natural rainfall storage capacity. Third, the two multiple increase of natural resources application can bring trillions of resource activation, environmental cleaning, food security, citizens, health, economic, ecological and social benefits, and makes the Chinese nation move forward in green development. Its application in "big scientific research" and "One Belt And One Road" will contribute Chinese strength to the world. 展开更多
关键词 Fenlong green development Multiple use of natural resource Increase three-dimensional land space Recommended cultivation technique by the Ministry of Agriculture of China Big scientific research
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儒学、西学与天文——清中期张永祚《天象源委》研究
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作者 朱浩浩 石云里 《自然科学史研究》 CSSCI CSCD 北大核心 2021年第3期305-316,共12页
张永祚是清中期重要天文学家,在钦天监供职多年。文章在儒学、西学与天文学交叉视野下,从三个方面考察张氏的代表作——关于星占的《天象源委》:首先,论述了《天象源委》产生的背景,即明末到清中期欧洲与伊斯兰古典星占学、传统军国占... 张永祚是清中期重要天文学家,在钦天监供职多年。文章在儒学、西学与天文学交叉视野下,从三个方面考察张氏的代表作——关于星占的《天象源委》:首先,论述了《天象源委》产生的背景,即明末到清中期欧洲与伊斯兰古典星占学、传统军国占以及星命术在中国的发展,以及它们与儒学的关系;其次,讨论《天象源委》以欧洲与伊斯兰星占为主,以传统军国占中望气、审音、军占为辅的独特星占技术体系;最后,从儒学的角度考察张氏如何以星占为儒者格物穷理之学,并将其置于儒家经典如《易经》之上。文章还结合前人研究,就张氏天文学工作所展示的中国古代科学形态、他的这项工作与儒学的关系以及中西交流问题进行了讨论。 展开更多
关键词 张永祚 《天象源委》 儒学 西学 天文学
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Comparison of stand structure and growth between artificial and natural forests of Pinus sylvestiris var. mongolica on sandy land 被引量:21
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作者 朱教君 范志平 +2 位作者 曾德慧 姜凤岐 MATSUZAKI Takeshi 《Journal of Forestry Research》 SCIE CAS CSCD 2003年第2期103-111,共9页
Mongolian pine (Pinus sylvestiris Linnaeus var. mongolica Litvinov) as a valuable conifer tree species has been broadly introduced to the sandy land areas in 揟hree North?regions (North, northwest and northeast of Chi... Mongolian pine (Pinus sylvestiris Linnaeus var. mongolica Litvinov) as a valuable conifer tree species has been broadly introduced to the sandy land areas in 揟hree North?regions (North, northwest and northeast of China), but many problems occurred in the earliest Mongolian pine plantations in Zhanggutai, Zhangwu County, Liaoning Province (ZZL). In order to clarify the reason, comprehensive investigations were carried out on differences in structure characteristics, growth processes and ecological factors between artificial stands (the first plantation established in ZZL in 1950s) and natural stands (the origin forests of the tree species in Honghuaerji, Inner Mongolia) on sandy land. The results showed that variation of diameter-class distributions in artificial stands and natural stands could be described by Weibull and Normal distribution models, respectively. Chapman-Richards growth model was employed to reconstruct the growth process of Mongolian pine based on the data from field investigation and stem analysis. The ages of maximum of relative growth rate and average growth rate of DBH, height, and volume of planted trees were 11, 22 years, 8, 15 years and 35, 59 years earlier than those of natural stand trees, respectively. In respect of the incremental acceleration of volume, the artificial and natural stands reached their maximum values at 14 years and 33 years respectively. The quantitative maturity ages of artificial stands and natural stands were 43 years and 102 years respectively. It was concluded that the life span of the Mongolian pine trees in natural stands was about 60 years longer than those in artificial stands. The differences mentioned above between artificial and natural Mongolian pine forests on sandy land were partially attributed to the drastic variations of ecological conditions such as latitude, temperature, precipitation, evaporation and height above sea level. Human beings' disturbances and higher density in plantation forest may be ascribed as additional reasons. Those results may be potentially useful for the management and afforestation of Mongolian pine plantations on sandy land in arid and semi-arid areas. 展开更多
关键词 Pinus sylvestiris var. mongolica Mongolian pine Sandy land COMPARISON Growth model
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Natural regeneration characteristics of Pinus sylvestris var. mongolica forests on sandy land in Honghuaerji, China 被引量:20
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作者 ZHU Jiao-jun KANG Hong-zhang +2 位作者 TAN Hui XU Mei-ling WANG Jun 《Journal of Forestry Research》 SCIE CAS CSCD 2005年第4期253-259,共7页
Natural regeneration in Mongolian pine, Pinus sylvesttis var. mongolica, forest at Honghuaerji of China (the original of the natural Mongolian pine, forest on sandy land) was studied in 2004. The total mean values o... Natural regeneration in Mongolian pine, Pinus sylvesttis var. mongolica, forest at Honghuaerji of China (the original of the natural Mongolian pine, forest on sandy land) was studied in 2004. The total mean values of regeneration indexes were higher in mature stands (more than 80% individual stems were older than 50 years), the maximum of regeneration index reached 29 seedlings, m^ 2, with lowest values in the younger stand, e.g., in 32-year old and 43-year old stands. The stand age was an important factor determining the natural regeneration, which was the best in the older stands in this investigation (e.g. about 80-year old). The regeneration index seemed not to be closely in relation to canopy openness although Mongolian pine is a photophilic tree species. In each type of gaps, natural regeneration was very well. Regeneration indexes were satisfactory at the south and east edges in the circle gaps; and at the east edge of the narrow-square gaps. Results indicated that Mongolian pine, seedlings could endure shading understory, but it would not enter the canopy layer without gap or large disturbance, e.g., fire, wind/snow damage or clear cutting etc. These results may provide potentially references to the management and afforestation of Mongolian pine, plantations on sandy land in arid and semi-arid areas. Researches such as the comprehensive comparisons on regeneration, structure and ecological conditions and so on between natural Mongolian pine, forests and plantations should be conducted in the future. 展开更多
关键词 Pinus sylvestris var. mongolica Mongolian pine Sandy land Natural regeneration Canopy openness Forest gap Regeneration index
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An OGC standard-oriented architecture for distributed coal mine map services 被引量:5
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作者 SONG Xian-feng RUI Xiao-ping +1 位作者 HOU Wei TAN Hai-qiao 《Journal of China University of Mining and Technology》 EI 2008年第3期381-385,共5页
GIS- or CAD-based technology has been widely used for cartographic maps in coal mines, but structural gaps between such maps make it difficult to provide an integrated map service, for any specific purpose, at higher ... GIS- or CAD-based technology has been widely used for cartographic maps in coal mines, but structural gaps between such maps make it difficult to provide an integrated map service, for any specific purpose, at higher levels. There is no uniform platform that can be used to manage all involved maps. The main reason for this is that datasets are submitted by individual coal mines using their individual, diverse software. No consistent model is used within the software for data abstraction and symbolization. This paper first reviews all the essential specifications concerning OGC (Open Geospatial Consortium) interoperability. Then an OGC standard-oriented architecture is proposed to provide distributed coal mine map services. Within this new architecture the management of spatial data archives, and the integration of coal mine maps, are achieved through the interfaces of geospatial services. Finally an open source geospatial approach is suggested to implement the proposed scheme. A case study of the Huaibei Coal Group is used to demonstrate the proposal. 展开更多
关键词 coal mine map services service oriented architecture OGC interoperability specifications open source geospatial solution
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Utilisation and Management Changes in South Kyrgyzstan's Mountain Forests 被引量:3
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作者 Matthias Schmidt 《Journal of Mountain Science》 SCIE CSCD 2005年第2期91-104,共14页
Using political ecology as its conceptual framework,this paper focuses on the changes in forest utilisation and management of South Kyrgyzstan’s walnut-fruit forests over the last century. The aim of this study on hu... Using political ecology as its conceptual framework,this paper focuses on the changes in forest utilisation and management of South Kyrgyzstan’s walnut-fruit forests over the last century. The aim of this study on human-environment interactions is to investigate the relationship between actors on the one side,their interests and demands,and the forests and forested lands on the other. Forest resource utilisation and management — and even the recognition of different forest products as resources — are connected with political and socio-economic conditions that change with time. The walnut-fruit forests of South Kyrgyzstan are unique,characterised by high biodiversity and a multiplicity of usable products;and they have been utilised for a long time. Centralised and formal management of the forests started with the Russian occupation and was strengthened under Soviet rule,when the region became a part of the USSR. During this era,a state forest administration that was structured from Moscow all the way down to the local level drew up detailed plans and developed procedures for utilising the different forest products. Since the collapse of the Soviet Union,the socio-political and economic frame conditions have changed significantly,which has brought not only the sweeping changes in the managing institutions,but also the access rights and interests in the forest resources. At present,the region is suffering from a high unemployment rate,which has resulted in the forests’ gaining considerable importance in the livelihood strategies of the local population. Political and economic liberalization,increased communication and trans-regional exchange relations have opened the door for international companies and agents interested in the valuable forest products. Today,walnut wood and burls,walnuts,wild apples and mushrooms are all exported to various countries in the world. Scientists and members of various international organisations stress the ecological value of the forests and are trying to establish nature conservation areas. Nevertheless,it is to fear that a multiplicity of interrelated factors — the present transformation and globalization processes,the appearance of new actors,the local population’s insecure economic situation and the erosion of managing institutions — are all leading to an intensified and unregulated exploitation of the forests,resulting in their degradation. 展开更多
关键词 KYRGYZSTAN Tian Shan walnut-fruit forest political ecology resource management forest utilisation
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1-D Controlled source electromagnetic forward modeling for marine gas hydrates studies 被引量:3
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作者 赵峦啸 耿建华 +1 位作者 张胜业 杨迪琨 《Applied Geophysics》 SCIE CSCD 2008年第2期121-126,共6页
We discuss the feasibility of using controlled-source electromagnetic (CSEM) in the frequency domain for prospecting marine gas hydrates. Based on the Ocean Drilling Program (ODP) Leg 164 log data, we have establi... We discuss the feasibility of using controlled-source electromagnetic (CSEM) in the frequency domain for prospecting marine gas hydrates. Based on the Ocean Drilling Program (ODP) Leg 164 log data, we have established several 1-D resistivity models which have different gas hydrate concentrations. Meanwhile, we analyzed the electromagnetic response of marine gas hydrates in the frequency domain based on these models. We also studied the relationship between electrical field magnitude or phase and parameters such as receiver-transmitter distance and frequency. Our numerical modeling results provide us with a quantitative reference for exploration and resource evaluation of marine gas hydrates. 展开更多
关键词 gas hydrate CSEM forward modeling resource evaluation
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Operation Performance of Air Source Heat Pump System for Space Heating in Tianjin 被引量:2
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作者 赵军 陈雁 +1 位作者 曲航 李新国 《Transactions of Tianjin University》 EI CAS 2007年第2期137-141,共5页
An air source heat pump system (ASHPS) used in an office building is set up and studied experimentally. Its operating performance in winter is evaluated based on test data and a comparative discussion is given on the ... An air source heat pump system (ASHPS) used in an office building is set up and studied experimentally. Its operating performance in winter is evaluated based on test data and a comparative discussion is given on the effect of climate conditions and heating load ratio on the operation behavior. Then heating capacity variation caused by evaporator frosting is analyzed as well. Finally, the defrosting parameters and the technical feasibility are studied for a constant heating demand. The experimental results indicate that both the outlet water temperature drop and the system COP should be taken into account when setting defrosting parameters, and ASHPS is a viable technology for space heating and hot-water production in winter in Tianjin, which can maintain the room temperature above 19 ℃ when the outdoor temperature is -2 ℃. 展开更多
关键词 air source heat pump system(ASHPS) space heating defrosting parameter COP
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Oasis System and Its Reasonable Development in Sangong River Watershed in North of the Tianshan Mountains,Xinjiang,China 被引量:3
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作者 LEI Jun LUO Geping +1 位作者 ZHANG Xiaolei LU Qi 《Chinese Geographical Science》 SCIE CSCD 2006年第3期236-242,共7页
Under the guide of system theory, taking the oasis in the Sangong River watershed as a case study, this paper analyzes the oasis structure and function from 4 aspects including oasis spatial structure, water resources... Under the guide of system theory, taking the oasis in the Sangong River watershed as a case study, this paper analyzes the oasis structure and function from 4 aspects including oasis spatial structure, water resources structure, vegetation structure, economic structure and their corresponding functions. The results indicate that as a typical small-scale watershed, Sangong River watershed has the relatively complete mountain-basin structure, and ecological and productive function. Because of human drastic activity the utilization rate of water resources was as high as 98.7%, and the utilization of groundwater was not reasonable, which resulted in an average annual decline of 0.353m in the water table of alluvial-diluvial-fan oasis, and an average annual increase of 0.047m in the alluvial-plain. The layout of crop and shelter forest benefits to the utilization of water and land resources. The development of oasis economy is at low level, and its eco-economic function is weak. 展开更多
关键词 oasis structure oasis function oasis economy Sangong River watershed
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Examination of Resource Curse Hypothesis: Mineral Resources Exploitation and Economic Growth in Xinjiang Autonomous Region 被引量:2
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作者 Zhang Xinhua Gu Shuzhong +3 位作者 Wang Xingjie Wu Hong Zhou Hong Hu Yongjun 《Chinese Journal of Population,Resources and Environment》 2011年第1期63-70,共8页
The mineral resources exploitation stage and the economic growth rate are various in different regions of Xinjiang Autonomous region. Using the method of location quotient, this paper identifies and classifies the int... The mineral resources exploitation stage and the economic growth rate are various in different regions of Xinjiang Autonomous region. Using the method of location quotient, this paper identifies and classifies the intensive regions of three types of mineral resources, known as coal, oil and natural gas, respectively. The intensive regions of economic growth were also identified, according to the rate of per capita GDP growth at prefecture, autonomous prefecture and city. The relationships between different mineral resources and economic growth are different, for example, the relationship between economic growth and coal resource is positive, while the relationship between economic growth and oil resource, or natural gas resource is negative. This study empirically examines the effects of natural resources on economic growth of Xinjiang. The results show that whilst natural resources have a positive impact on growth, and can make a negative impact on growth through the transmission channels, such as investment, manufacture, human capital, and scientific and technologic innovation. Moreover, it studies the transmission channels, that is, the effect of natural resources on the other explanatory variables, and calculates the indirect effect of natural resources on growth for each transmission channel, and comprehensive effects of natural resources on growth. The calculated result of comprehensive effects indicates that the positive direct effects of natural resources on growth are shown to outweigh the negative indirect effect of Xinjiang autonomous region. 展开更多
关键词 mineral resources exploitation economics growth EFFECTS resource curse XINJIANG
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Carbon sequestration of plantation in Beijing-Tianjin sand source areas 被引量:3
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作者 LIU Xiu-ping ZHANG Wan-jun +2 位作者 CAO Jian-sheng YANG Bai CAI Yan-jiang 《Journal of Mountain Science》 SCIE CSCD 2018年第10期2148-2158,共11页
The Beijing-Tianjin Sand Source Control Project(BTSSCP), a national ecological restoration project, was launched to construct an ecological protection system in the Beijing-Tianjin sand source areas to reduce dust haz... The Beijing-Tianjin Sand Source Control Project(BTSSCP), a national ecological restoration project, was launched to construct an ecological protection system in the Beijing-Tianjin sand source areas to reduce dust hazards. The carbon sequestration dynamics can be used to assess the ecological effects of an ecological restoration project. Here, we conducted vegetation and soil study to assess the carbon sequestration in the plantations with 10 years old stands in Beijing-Tianjin sand source areas. The results at the site scales indicated that the average net increase of plantation ecosystem carbon stock was 33.8 Mg C ha^(-1), with an annual increase rate of 3.38 Mg C ha^(-1) yr^(-1). The average net increase of carbon varied among regions, vegetation types, and forest management activities. Soil bulk density in the top soil decreased slightly after 10-year implementation of the project. Coniferous forests and shrubs are suitable plant species for sand source areas.Natural restoration in the plantations is a practical and feasible and promising approach for enhancing ecosystem carbon sequestration potential. 展开更多
关键词 AFFORESTATION Carbon sequestration Carbon density Forest management RESTORATION Sand source control
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Assessing the kinetic model of hydro-distillation and chemical composition ofAquilaria malaccensis leaves essential oil 被引量:3
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作者 Mahtab Samadi Zurina Zainal Abidin +3 位作者 Robiah Yunus Dayang Radiah Awang Biak Hiroyuki Yoshida Eng Hai Lok 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2017年第2期216-222,共7页
This study aimed to model the kinetic of hydro-distillation of Aquilaria malaccensis leaves oil in order to understand and optimize the extraction process. In addition, this study, for the first time, aimed to identif... This study aimed to model the kinetic of hydro-distillation of Aquilaria malaccensis leaves oil in order to understand and optimize the extraction process. In addition, this study, for the first time, aimed to identify the chemical compositions of the A. rnalaccensis leave-oil. By assessing both first-order kinetic model and the model of simultaneous washing and diffusion, the result indicated that the model of simultaneous washing and diffusion better describes the hydro-distillation mechanism of the essential oil from A. rnalaccensis leaves. The optimum time, solid to liquid ratio, and the heating power for extracting the highest amount of essential oil were found to be around 3 h, 1:10 (g. ml-1), and 300 W respectively. Yellow essential oil with a strong smell and a yield of 0.05 v/w was extracted by hydro-distillation Clevenger apparatus. Chemical compounds of the essential oil were analyzed using gas chromatography-mass spectroscopy (GC/MS), which resulted in identification of 42 compounds that constitute 93% of essential oil. Among the identified components, Pentadecanal (32.082%), 9-Octadecenal, (Z) (15.894%), and Tetradecanal (6.927%) were the major compounds. Considering the fact that all the identified major components possess pesticidal properties, A. malaccensis leaves can be regarded as a promising natural source for producing pesticides. 展开更多
关键词 Aquilaria malaccensisEssential oilHydro-distillationOptimizationKinetic modeling
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Current status and prospect of fisheries resource enhancement in Tianjin 被引量:2
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作者 GAO Yan DAI Yuan-yuan +1 位作者 ZHANG Xue WANG Hong 《Marine Science Bulletin》 CAS 2019年第1期79-86,共8页
Based on the data of releasing and enhancement of Tianjin Bohai Sea Fisheries Research Institute,this study has entirely summarized the experiences and achievements on releasing and enhancement works in Tianjin since ... Based on the data of releasing and enhancement of Tianjin Bohai Sea Fisheries Research Institute,this study has entirely summarized the experiences and achievements on releasing and enhancement works in Tianjin since 2006.Since 2006,Tianjin has launched the first multi-proliferation and release activity with"Fenneropenaeus chinensis"as the leader.So far,more than 22 varieties have been proliferated,among which crustaceans are dominant.There are significant ecological,economic and social benefits.Both national and international development trends of releasing and enhancement are summarized,and demands and objective of industrial development are proposed. 展开更多
关键词 fisheries resources releasing and enhancement TIANJIN
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A 10kW-scale Distributed Power Plant of Natural Gas-Proton Exchange Membrane Fuel Cell 被引量:1
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作者 BAO Cheng SU Qingquan +5 位作者 MI Wanliang LI Zhiyuan HI Quan JI Zhonghua LIU Zhixiang MAO Zongqiang 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2010年第6期988-994,共7页
A 10 kW-scale natural gas fueled proton exchange membrane fuel cell(PEMFC) distributed power plant is presented in this paper,which is designed for cogeneration of power and heat. With homemade catalysts for CO remova... A 10 kW-scale natural gas fueled proton exchange membrane fuel cell(PEMFC) distributed power plant is presented in this paper,which is designed for cogeneration of power and heat. With homemade catalysts for CO removal in a two-stage methanation process and integrated reactor in the fuel processing system,the reformed fuel with CO molar fraction less than 10-5 is obtained for the fuel cell stack. Based on Matlab/Simulink/Stateflow and xPC Target platform,a rapid control prototype(RCP) is developed for real-time condition management,signal tracking and parameter tuning,data storing,and man-machine interaction. In a typical running with 4.3 kW stack power,the hydrogen production efficiency,gross power generation efficiency and heat recovery efficiency approach to 76%,41% and 50%,respectively. The peak stack power reaches 7.3 kW. Though there is still considerable dis-tance to long-term operation at 10 kW-scale net power generation,it is a milestone for the PEMFC-based stationary application in China. 展开更多
关键词 proton exchange membrane fuel cell natural gas 10kW-scale power plant two-stage methanation xPC-based rapid control prototype
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A new generic open pit mine planning process with risk assessment ability 被引量:2
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作者 Ngoc Luan Mai Oktay Erten Erkan Topal 《International Journal of Coal Science & Technology》 EI 2016年第4期407-417,共11页
Conventionally, mining industry relies on a deterministic view, where a unique mine plan is determined based on a single resource model. A major shortfall of this approach is the inability to assess the risk caused by... Conventionally, mining industry relies on a deterministic view, where a unique mine plan is determined based on a single resource model. A major shortfall of this approach is the inability to assess the risk caused by the well-known geological uncertainty, i.e. the in situ grade and tonnage variability of the mineral deposit. Despite some recent attempts in developing stochastic mine planning models which have demonstrated promising results, the industry still remains sceptical about this innovative idea. With respect to unbiased linear estimation, kriging is the most popular and reliable deterministic interpolation technique for resource estimation and it appears to remain its popularity in the near future. This paper presents a new systematic framework to quantify the risk of kriging-based mining projects due to the geological uncertainties. Firstly, conditional simulation is implemented to generate a series of equally-probable orebody realisations and these realisations are then compared with the kriged resource model to analyse its geological uncertainty. Secondly, a production schedule over the life of mine is determined based on the kriged resource model. Finally, risk profiles of that production schedule, namely ore and waste tonnage production, blending grade and Net Present Value (NPV), are constructed using the orebody realisations. The proposed model was applied on a multi-element deposit and the result demonstrates that that the kriging-based mine plan is unlikely to meet the production targets. Especially, the kriging-based mine plan overestimated the expected NPV at a magnitude of 6.70% to 7.34% (135 M$ to 151 M$). A new multivariate conditional simulation framework was also introduced in this paper to cope with the multivariate nature of the deposit. Although an iron ore deposit is used to prove the concepts, the method can easily be adapted to other kinds of mineral deposits, including surface coal mine. 展开更多
关键词 Open pit mine planning Geological uncertainty Multivariate conditional simulation Grade/tonnage curves
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Sorption behavior of coal for implication in coal bed methane an overview 被引量:9
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作者 Manasi Manjari Mohanty Bhatu Kumar Pal 《International Journal of Mining Science and Technology》 SCIE EI CSCD 2017年第2期307-314,共8页
CBM has been recognized as a significant natural gas resource for a long time. Recently, CO_2 sequestration in coalbeds for ECBM has been attracting growing attention because of greater concerns about the effects of g... CBM has been recognized as a significant natural gas resource for a long time. Recently, CO_2 sequestration in coalbeds for ECBM has been attracting growing attention because of greater concerns about the effects of greenhouse gases and the emerging commercial significance of CBM. Reservoir-simulation technology,as a useful tool of reservoir development, has the capability to provide us with an economic means to solve complex reservoir-engineering problems with efficiency. The pore structure of coal is highly heterogeneous, and the heterogeneity of the pores depends on the coal type and rank. 展开更多
关键词 ECBM Greenhouse gases Sequestration Adsorption and desorption Porosity and permeability
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Study on the Source Parameters of Earthquakes in the Middle Eastern Area of North Tianshan in Xinjiang 被引量:1
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作者 Zhao Cuiping Xia Aiguo +1 位作者 Zheng Sihua Chen Zhangli 《Earthquake Research in China》 2005年第4期381-390,共10页
By applying the empirical Green's function method, we first proved that the source spectra in the middle eastern area of North Tianshan follow the ω^-2 Brune model, and then, on this basis, obtained the source spect... By applying the empirical Green's function method, we first proved that the source spectra in the middle eastern area of North Tianshan follow the ω^-2 Brune model, and then, on this basis, obtained the source spectra for 105 earthquakes of ML 2.5 - 5.7 in the studied area upon removing the noise, instrument, propagation and site effects in the observational seismic S waveforms. Finally, we determined the source parameters such as the seismic moment, stress drop, source dimension, etc., based on the Brune model. The results show that there is a good linear correlation between scalar seismic moment, M0, and ML, which is Log10 M0 = 1.10 ML + 17.20; The source radii range between 100- 1500m; the stress drop, 1-16MPa with a predominant range of 1 - 10MPa. The relationship of the seismic moment versus corner frequencies indicates that there may exist two source scaling, that is, when M0 〈 4×10^21 dyne. cm (equal to an ML4.0 event), stress drop is weakly dependent on M0: whereas, when M0 〉 4×10^21 dyne·cm, stress drop is independent of M0. 展开更多
关键词 North Tianshan in Xinjiang Source spectrum Source model Source parameter Source scaling
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