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Effects of Different Seed Stem Sizes on the Changes of Available Elements in Rhizosphere Soil of Fritillaria thunbergii Miq.
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作者 Yong PENG Rui PAN +3 位作者 Zhengyan LIU Xiaohong WU Nong ZHOU Wenwu YANG 《Agricultural Biotechnology》 2024年第3期18-23,共6页
[Objectives]This study was conducted to screen suitable seed stems of Fritillaria thunbergii Miq.from different provenances and to provide a theoretical basis for the high-yielding and high-efficiency cultivation of F... [Objectives]This study was conducted to screen suitable seed stems of Fritillaria thunbergii Miq.from different provenances and to provide a theoretical basis for the high-yielding and high-efficiency cultivation of F.thunbergii Miq.introduced to different places.[Methods]F.thunbergii Miq.from four different provenances including Zhejiang,Nantong and Chongqing were introduced and cultivated in Wanzhou of Chongqing.The contents of available Zn,Fe,Mn,Cu,Mo,N,P,K,Ca and Mg in rhizosphere soil of F.thunbergii Miq.during five growing stages were determined after selecting different stem sizes for field cultivation.[Results]Small stems of Pan an and Ningbo provenances(SSG3,121-160/kg)and middle stems of Nantong and Fengjie provenances(SSG2,81-120/kg)showed higher soil availability.[Conclusions]In the process of introduction and cultivation of F.thunbergii Miq.,high yield and high efficiency can be achieved by selecting smaller seed stems of F.thunbergii Miq. 展开更多
关键词 Fritillaria thunbergii Miq. Different provenances Stem size INTRODUCTION CULTIVATION Soil nutrient element availABILITY
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A two-step method to detect broadcast ephemeris unavailable periods caused by BeiDou satellite orbital maneuvers
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作者 Jingjing Wang Chao Zhou Zhixuan Sun 《Geodesy and Geodynamics》 EI CSCD 2023年第5期456-466,共11页
The space constellation of the BeiDou navigation satellite system(BDS) is a hybrid constellation containing medium earth orbit(MEO) satellites, geostationary earth orbit(GEO) satellites, and inclined geosynchronous or... The space constellation of the BeiDou navigation satellite system(BDS) is a hybrid constellation containing medium earth orbit(MEO) satellites, geostationary earth orbit(GEO) satellites, and inclined geosynchronous orbit(IGSO) satellites. Due to the geosynchronous characteristics of GEO and IGSO, GEO satellites and IGSO satellites often need to perform orbital maneuvers, which can affect the signal-inspace(SIS) availability performance of BeiDou satellites. A two-step detection method for BeiDou satellite orbital maneuvers has been proposed in this paper. The first step is to identify orbital maneuvers based on time series analysis of broadcast ephemeris, and the second step is to verify orbital maneuvers based on bidirectional orbit prediction. The two-step detection method was used to detect the orbital maneuvers of BeiDou satellites in 2019. Through the double guarantees of identification and verification,the detection accuracy of BeiDou satellite orbital maneuvers has been effectively improved. And the orbital maneuver detection results are continued to be used to assess the SIS availability of BeiDou satellites. The results show that the availability loss of GEO satellite orbital maneuvers is about 0.45%-1.07%, and the availability loss of IGSO satellite orbital maneuvers is about 0.12%-0.19%. 展开更多
关键词 BDS Orbital maneuver Signal-in-space availABILITY Time series analysis
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Assessment of Super Absorbent Polymer (SAP) on Plant Available Water (PAW) in Dry Lands
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作者 Vincent Ng’eno Christian Omuto +1 位作者 Duncan Mbuge Vitalis Too 《Engineering(科研)》 CAS 2023年第2期90-105,共16页
One of the ways of overcoming the cost of irrigation is through in-situ water harvesting at the plant roots. Super absorbent polymer (SAP) can facilitate water harvesting at the plant roots. This study attempted to as... One of the ways of overcoming the cost of irrigation is through in-situ water harvesting at the plant roots. Super absorbent polymer (SAP) can facilitate water harvesting at the plant roots. This study attempted to assess the effect of SAP on plant available water (PAW) of different soils. In this study, SAP was sequentially added at the rate of 0.2%, 0.3% and 0.5% of the soil weight and its impact assessed in clay, sandy clay and sandy loam soils. The moisture retention characteristics of the original and SAP treated soils were studied using soil water retention curves (SWRC) and results modelled using Gardner model. PAW was estimated from SWRC as the difference between moisture content at 1.5 and 3 bar in all soils. The difference in PAW between original and treated soils was assessed at 5% level of significance. The WRC of all the samples was adequately found to be described by the Gardner model (Coefficient of determination R<sup>2</sup> ≥ 98% and residual standard error (RSE) ≤ 0.04). SWRC changed with increase in SAP percentage in clay, sandy clay and sandy loam soils. Clay had a higher change in water retention then sandy clay and lastly sandy loam. Plant available water content (PAW) in all soils increased. In clay soil it increased with increase in SAP from 0.3291 at zero SAP to 0.6223 at 0.5% SAP. Sandy clay soil increased in PAW from 0.2721 at zero SAP to 0.5335 at 0.5% SAP and Sandy loam soils from 0.1691 at zero SAP to 0.3461 at 0.5% SAP. Hence, from the study SAP can be used to conserve irrigation water in the plant roots and therefore reducing the cost since PAW has been increased. 展开更多
关键词 Plant available Water (PAW) Soil Water Retention Curve (SWRC) SOIL Super Absorbent Polymer (SAP)
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Improving Network Availability through Optimized Multipath Routing and Incremental Deployment Strategies
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作者 Wei Zhang Haijun Geng 《Computers, Materials & Continua》 SCIE EI 2024年第7期427-448,共22页
Currently,distributed routing protocols are constrained by offering a single path between any pair of nodes,thereby limiting the potential throughput and overall network performance.This approach not only restricts th... Currently,distributed routing protocols are constrained by offering a single path between any pair of nodes,thereby limiting the potential throughput and overall network performance.This approach not only restricts the flow of data but also makes the network susceptible to failures in case the primary path is disrupted.In contrast,routing protocols that leverage multiple paths within the network offer a more resilient and efficient solution.Multipath routing,as a fundamental concept,surpasses the limitations of traditional shortest path first protocols.It not only redirects traffic to unused resources,effectively mitigating network congestion,but also ensures load balancing across the network.This optimization significantly improves network utilization and boosts the overall performance,making it a widely recognized efficient method for enhancing network reliability.To further strengthen network resilience against failures,we introduce a routing scheme known as Multiple Nodes with at least Two Choices(MNTC).This innovative approach aims to significantly enhance network availability by providing each node with at least two routing choices.By doing so,it not only reduces the dependency on a single path but also creates redundant paths that can be utilized in case of failures,thereby enhancing the overall resilience of the network.To ensure the optimal placement of nodes,we propose three incremental deployment algorithms.These algorithms carefully select the most suitable set of nodes for deployment,taking into account various factors such as node connectivity,traffic patterns,and network topology.By deployingMNTCon a carefully chosen set of nodes,we can significantly enhance network reliability without the need for a complete overhaul of the existing infrastructure.We have conducted extensive evaluations of MNTC in diverse topological spaces,demonstrating its effectiveness in maintaining high network availability with minimal path stretch.The results are impressive,showing that even when implemented on just 60%of nodes,our incremental deployment method significantly boosts network availability.This underscores the potential of MNTC in enhancing network resilience and performance,making it a viable solution for modern networks facing increasing demands and complexities.The algorithms OSPF,TBFH,DC and LFC perform fast rerouting based on strict conditions,while MNTC is not restricted by these conditions.In five real network topologies,the average network availability ofMNTCis improved by 14.68%,6.28%,4.76%and 2.84%,respectively,compared with OSPF,TBFH,DC and LFC. 展开更多
关键词 Multipath routing network availability incremental deployment schemes genetic algorithm
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谈谈available在医学文献中的译法
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作者 何祖佳 《世界今日医学杂志》 2002年第9期793-794,共2页
关键词 医学文献 available 译法
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Distribution of available soil water capacity in China 被引量:57
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作者 ZHOUWenzuo LIUGaohuan +1 位作者 PANJianjun FENGXianfeng 《Journal of Geographical Sciences》 SCIE CSCD 2005年第1期3-12,共10页
The available soil water capacity (ASWC) is important for studying crop production, agro-ecological zoning, irrigation planning, and land cover changes. Laboratory determined data of ASWC are often not available for m... The available soil water capacity (ASWC) is important for studying crop production, agro-ecological zoning, irrigation planning, and land cover changes. Laboratory determined data of ASWC are often not available for most of soil profiles and the nationwide ASWC largely remains lacking in relevant soil data in China. This work was to estimate ASWC based on physical and chemical properties and analyze the spatial distribution of ASWC in China. The pedo-transfer functions (PTFs), derived from 220 survey data of ASWC, and the empirical data of ASWC based on soil texture were applied to quantify the ASWC. GIS technology was used to develop a spatial file of ASWC in China and the spatial distribution of ASWC was also analyzed. The results showed the value of ASWC ranges from 15 × 10-2 cm3·cm-3 to 22 × 10-2 cm3·cm-3 for most soil types, and few soil types are lower than 15 × 10-2 cm3·cm-3 or higher than 22 × 10-2 cm3·cm-3. The ASWC is different according to the complex soil types and their distribution. It is higher in the east than that in the west, and the values reduce from south to north except the northeastern part of China. The "high" values of ASWC appear in southeast, northeastern mountain regions and Northeast China Plain. The relatively "high" values of ASWC appear in Sichuan basin, Huang-Huai-Hai plain and the east of Inner Mongolia. The relatively "low" values are distributed in the west and the Loess Plateau of China. The "very low" value regions are the northern Tibetan Plateau and the desertified areas in northern China. In some regions, the ASWC changes according to the complex topography and different types of soils. Though there remains precision limitation, the spatial data of ASWC derived from this study are improved on current data files of soil water retention properties for Chinese soils. This study presents basic data and analysis methods for estimation and evaluation of ASWC in China. 展开更多
关键词 available soil water capacity pedo-transfer functions China
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Strategies for multi-step-ahead available parking spaces forecasting based on wavelet transform 被引量:4
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作者 季彦婕 高良鹏 +1 位作者 陈晓实 郭卫红 《Journal of Central South University》 SCIE EI CAS CSCD 2017年第6期1503-1512,共10页
A new methodology for multi-step-ahead forecasting was proposed herein which combined the wavelet transform(WT), artificial neural network(ANN) and forecasting strategies based on the changing characteristics of avail... A new methodology for multi-step-ahead forecasting was proposed herein which combined the wavelet transform(WT), artificial neural network(ANN) and forecasting strategies based on the changing characteristics of available parking spaces(APS). First, several APS time series were decomposed and reconstituted by the wavelet transform. Then, using an artificial neural network, the following five strategies for multi-step-ahead time series forecasting were used to forecast the reconstructed time series: recursive strategy, direct strategy, multi-input multi-output(MIMO) strategy, DIRMO strategy(a combination of the direct and MIMO strategies), and newly proposed recursive multi-input multi-output(RECMO) strategy which is a combination of the recursive and MIMO strategies. Finally, integrating the predicted results with the reconstructed time series produced the final forecasted available parking spaces. Three findings appear to be consistently supported by the experimental results. First, applying the wavelet transform to multi-step ahead available parking spaces forecasting can effectively improve the forecasting accuracy. Second, the forecasting resulted from the DIRMO and RECMO strategies is more accurate than that of the other strategies. Finally, the RECMO strategy requires less model training time than the DIRMO strategy and consumes the least amount of training time among five forecasting strategies. 展开更多
关键词 available PARKING spaces MULTI-STEP AHEAD time series forecasting wavelet transform forecasting STRATEGIES RECURSIVE multi-input MULTI-OUTPUT strategy
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Preliminary Study on Spatial Variability and Distribution of Soil Available Microelements in Pinggu County, Beijing, China 被引量:3
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作者 WANG Shu-ying YU Tong-quan WANG Jian-li YANG Liu YANG Kai LU Ping 《Agricultural Sciences in China》 CAS CSCD 2008年第10期1235-1244,共10页
The objectives of this study were to explore the spatial distribution of soil available microelements and to provide a firm foundation for scientifically formulated fertilizer. 1 076 soil samples were collected from P... The objectives of this study were to explore the spatial distribution of soil available microelements and to provide a firm foundation for scientifically formulated fertilizer. 1 076 soil samples were collected from Pinggu County of Beijing, China, and the contents of available Cu, Zn, Fe, and Mn in topsoil (0-20 cm) and subsoil (20-40 cm) were analyzed respectively. Descriptive statistics and geostatistics were used to analyze the data. The mean values of topsoil available Cu, Zn, Fe, and Mn were 1.96, 2.51, 17.32, and 10.91 mg kg^-1, respectively, which were at medium or at slightly above medium level. The topsoil content of the soil available microelements was more than that of subsoil. The result of semivariance analysis showed that the topsoil available Fe and Mn were spatially correlated at a larger distance of 21.6 and 45.3 km, and the available Cu and Zn were at a shorter distance of 3.1 and 2.9 km, respectively. The subsoil spatial correlation distances were obviously different from the topsoil, which were in the order of available Mn 〉 Cu 〉 Zn = Fe. The Kriging method was applied to calculate the unobserved points and was used to generate the contour map. The results showed that the structural factors, such as topology, soil types, and soil properties, were the main factors influencing the spatial distribution of topsoil available Fe and Mn. Topsoil available Cu and Zn contents were mainly affected by land use, and their contents in orchard and in vegetable land were greatly higher than in field. The spatial distribution of subsoil microelements was similar to that of the topsoil, which exhibited vertical distribution patterns. Fertilizer and pesticide application resulted in the higher contents of available Cu and Zn in Pinggu County. The higher content of available Zn is potentially harmful to soil environmental quality, which should be inspected. 展开更多
关键词 soil available microelements SEMIVARIANCE spatial variability
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A model to estimate available timber and forest biomass and reforestation expenses in a mountainous region in Japan 被引量:2
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作者 Kazuhiro Aruga Ayami Murakami +3 位作者 Chikara Nakahata Reiko Yamaguchi Masashi Saito Kanae Kanetsuki 《Journal of Forestry Research》 SCIE CAS CSCD 2013年第2期345-356,共12页
We developed a model to estimate supply potentials and available amounts of timber and forest biomass resources from profitable sub-compartments of thinning and final felling operations. Economic balances were estimat... We developed a model to estimate supply potentials and available amounts of timber and forest biomass resources from profitable sub-compartments of thinning and final felling operations. Economic balances were estimated while considering not only harvesting expenses but also reforestation expenses after final felling, which should be considered for sustainable forest management. Harvesting expenses were estimated based on two types of timber harvesting systems and three types of forest biomass harvesting systems in each sub-compartment. Then, the model was applied to Nasushiobara city of Tochigi prefecture, Japan. Reforestation expenses had large negative impacts on the financial balances of final felling operations. Few sub-compartments were profitable after considering reforestation expenses. Most profitable sub-compartments were those with mechanized operation systems and landing sales. These accounted for 17.19% of all sub-compartments, while only 5.75% of the sub-compartments were profitable based on their current operation systems and landing sales. Although the overall supply potentials of timber and forest biomass resources were 380,000 m3 and 210,000 Mg, respectively, and 15 times the planned harvest of coniferous tree volume of 25,000 m3year-1 and 50 times the annual demand for the woody gasification power generation of 4,000 Mg year-1 in Nasushiobara, available amounts of timber and forest biomass resources were only49,429 m3 and 33,333 Mg, which were 13.0% and 15.7% of supply potentials for landing sales with mechanized operation systems. 展开更多
关键词 forest biomass resources supply potentials available amounts economic balance GIS
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Study on the Uncertainty of the Available Time Under Ship Fire Based on Monte Carlo Sampling Method 被引量:2
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作者 汪金辉 褚冠全 李开源 《China Ocean Engineering》 SCIE EI CSCD 2013年第1期131-140,共10页
Available safety egress time under ship fire (SFAT) is critical to ship fire safety assessment, design and emergency rescue. Although it is available to determine SFAT by using fire models such as the two-zone fire ... Available safety egress time under ship fire (SFAT) is critical to ship fire safety assessment, design and emergency rescue. Although it is available to determine SFAT by using fire models such as the two-zone fire model CFAST and the field model FDS, none of these models can address the uncertainties involved in the input parameters. To solve this problem, current study presents a framework of uncertainty analysis for SFAT. Firstly, a deterministic model estimating SFAT is built. The uncertainties of the input parameters are regarded as random variables with the given probability distribution functions. Subsequently, the deterministic SFAT model is employed to couple with a Monte Carlo sampling method to investigate the uncertainties of the SFAT. The Spearman's rank-order correlation coefficient (SRCC) is used to examine the sensitivity of each input uncertainty parameter on SFAT. To illustrate the proposed approach in detail, a case study is performed. Based on the proposed approach, probability density function and cumulative density function of SFAT are obtained. Furthermore, sensitivity analysis with regard to SFAT is also conducted. The results give a high-negative correlation of SFAT and the fire growth coefficient whereas the effect of other parameters is so weak that they can be neglected. 展开更多
关键词 ship fire ship fire available time Monte Carlo sampling uncertainty analysis sensitivity analysis
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Spatial and Temporal Variations in Available Soil Nitrogen—A Case Study in Kobresia Alpine Meadow in the Qinghai-Tibetan Plateau, China 被引量:4
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作者 Li Lin Guangmin Cao +7 位作者 Fawei Zhang Xun Ke Yikang Li Xingliang Xu Qian Li Xiaowei Guo Bo Fan Yangong Du 《Journal of Geoscience and Environment Protection》 2019年第3期177-189,共13页
Elucidating the factors that determine the effects of temporal and spatial variation of nutrients is important for analyzing the characteristics of an ecosystem. The goal of this paper was to estimate how values obtai... Elucidating the factors that determine the effects of temporal and spatial variation of nutrients is important for analyzing the characteristics of an ecosystem. The goal of this paper was to estimate how values obtained using a particular sampling approach correlated with the actual data for an entire plot. The mesh partition method was employed to divide an integrated observing field (IOF) located at the Haibei National Field Research Station of an alpine grassland ecosystem, China, into 25 subplots. Five of the 25 subplots were randomly selected for soil sampling and to determine the source of variations in soil nutrient content from 2001 to 2012. The results showed that, contributions of temporal and spatial variation in available nitrogen in the 0 - 10 cm soil layer accounted for 47.3% and 52.7%, respectively. The contribution of spatial variance was higher than that of temporal variance especially in the surface soil layers. The available soil nitrogen content in the alpine meadow was not obviously affected by fluctuations in rainfall and temperature. Increasing the number of samples could reduce calculation errors in measuring available soil nitrogen content, while collecting a reasonable number of samples can save time and labor. 展开更多
关键词 available Soil Nitrogen Source of NUTRIENT VARIATION TEMPORAL VARIATION Spatial VARIATION ALPINE MEADOW
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Meso-scale available gravitational potential in the world oceans 被引量:2
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作者 FENG Yang WANG Wei HUANG Ruixin 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2006年第5期1-13,共13页
The pitfalls of applying the commonly used definition of available gravitational potential energy (AGPE) to the world oceans are re-examined. It is proposed that such definition should apply to the meso-scale proble... The pitfalls of applying the commonly used definition of available gravitational potential energy (AGPE) to the world oceans are re-examined. It is proposed that such definition should apply to the meso-scale problems in the oceans, not the global scale. Based on WOA98 climatological data, the meso-scale AGPE in the world oceans is estimated. Unlike previous results by Oort et al. , the meso-scale AGPE is large wherever there is a strong horizontal density gradient. The distribution of meso-scale AGPE reveals the close connection between the baroclinic instability and the release of gravitational potential energy stored within the scale of Rossby deformation radius. 展开更多
关键词 energy of ocean circulation available potential gravitational energy MESO-SCALE baroclinic instability Rossby deformation radius
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Determination of the available energy values and amino acid digestibility of Flammulina velutipes stem waste and its effects on carcass trait and meat quality fed to growing-finishing pigs 被引量:6
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作者 Xuzhou Liu Bo Zhang +7 位作者 Hansuo Liu Gang Zhang Jinbiao Zhao Ling Liu Xiangshu Piao Hui Song Shuai Zhang Yu Li 《Journal of Animal Science and Biotechnology》 CAS CSCD 2020年第3期747-766,共20页
Background:Flammulina velutipes stem waste(FVS)is the by-product of mushroom industry.The objectives of this study were to determine the available energy and amino acid digestibility of FVS fed to pigs,and to evaluate... Background:Flammulina velutipes stem waste(FVS)is the by-product of mushroom industry.The objectives of this study were to determine the available energy and amino acid digestibility of FVS fed to pigs,and to evaluate the effects of dietary FVS inclusion on growth performance,biochemical profile of serum,fecal short chain fatty acid(SCFA)concentration,carcass traits,meat quality,intestinal morphology and microflora of pigs.In Exp.1,twelve crossbred barrows with initial body weight(IBW)of 37.48±4.31 kg were randomly allotted to 2 dietary treatments,including a corn basal diet and an experimental diet containing 24.35%FVS.In Exp.2,twelve barrows fitted with an ileal T-cannula(IBW:32.56±1.67 kg)were randomly allotted to 2 dietary treatments,which included a N-free diet and an experimental diet containing 40.0%FVS.In Exp.3,ninety growing pigs(IBW:63.98±6.89 kg)were allotted to 1 of 3 treatment diets for 63 d,including a basal diet and 2 experimental diets with 2.5%and 5%FVS,respectively.Results:The digestible energy(DE)and metabolizable energy(ME)of FVS were 4.58 and 4.06 MJ/kg on dry matter basis,respectively,and the standardized ileal digestibility(SID)of indispensable AAs ranged from 17.50%to 59.47%.Pigs fed diets with 2.5%FVS showed no difference on average daily gain(ADG)and gain to feed ratio(G/F).Although dietary 5%FVS inclusion impaired apparent total tract digestibility(ATTD)of organic matter and gross energy,it elevated the SCFA concentration(P≤0.04)in gut and antioxidant capacity in serum.In addition,dietary FVS inclusion depressed the backfat thickness(P=0.03)in pigs.The longissimus dorsi muscle of pigs fed FVS revealed higher n-3 polyunsaturated fatty acid concentration and optimized fatty acid composition.Dietary 2.5%FVS inclusion also improved the intestinal development and health by increasing the villius height to crypt depth ratio(V/C)in jejunum(P<0.01),and promoting microbial diversity and beneficial microbiota proliferation.Conclusions:It is feasible to include moderate content of FVS as an unconventional fiber ingredient in diet of growingfinishing pigs. 展开更多
关键词 Amino acid DIGESTIBILITY available energy Fiber Flammulina velutipes STEM WASTE Growing-finishing PIGS Growth performance MEAT quality
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Generalized Available Potential Energy 被引量:2
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作者 Yong.L.McHall 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 1990年第4期395-408,共14页
The kinetic energy generation in either the dry or moist atmosphere may be estimated by the same relationships if we introduce the new concept of generalized available potential energy. The largest magnitude of genera... The kinetic energy generation in either the dry or moist atmosphere may be estimated by the same relationships if we introduce the new concept of generalized available potential energy. The largest magnitude of generalized available potential energy and corresponding reference state of either dry or moist atmosphere are calculated in terms of the mitial conditions and entropy variation of the atmosphere. The obtained relationships are applicable for the statically unstable atmosphere as well. The generalized available potential energy associated with reversible processes reaches the maximum with respect to same initial state. While the generation of kinetic energy in irreversible processes is characterized by sudden changes. When the reference state is assumed to be saturated, we may predict the final temperature and moisture fields corresponding to provided initial state and entropy variation. 展开更多
关键词 Generalized available Potential Energy THAN AS
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Sufficiency and Deficiency Indices of Soil Available Zinc for Rice in the Alluvial Soil of the Coastal Yellow Sea 被引量:1
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作者 WEI Yi chang BAI You lu +6 位作者 JIN Ji yun YANG Li ping YAO Zheng XU Si xin Luo Guo an SONG Wei ZHU Chun mei 《Rice science》 SCIE 2007年第3期223-228,共6页
To determine the sufficiency and deficiency indices of soil available Zn by the Agro Services International (ASI) method (ASI-Zn) for Zn fertilizer recommendation in rice production in the alluvial soil of the coa... To determine the sufficiency and deficiency indices of soil available Zn by the Agro Services International (ASI) method (ASI-Zn) for Zn fertilizer recommendation in rice production in the alluvial soil of the coastal Yellow Sea, the relationship between relative rice yield and soil available ASI-Zn concentration was analyzed from a ten-field experiment with various soil test classes ranging from low to high fertility in 2005 and 2006, and nine Zn fertilizer application rates (0, 7.5 15, 22.5, 30, 37.5, 45, 52.5 and 60 kg Zn/ha) arranged at random with three replications in each field. There was a significant quadratic relationship between soil available ASI-Zn and rice yield, and a significant linear relationship between soil available ASI-Zn concentration and Zn fertilization rate. For rice variety Wuyujing 3, soil available ASI-Zn was deficient when the value was at lower than 1 mg Zn/L, low at 1 to 2 mg Zn/L, sufficient at 1 to 2 mg Zn/L, excessive at higher than 7.5 mg Zn/L. Thus, Zn fertilizer recommendation could be done according to the sufficiency and deficiency indices of soil ASI-Zn. For most of alluvial soils of the coastal Yellow Sea in the study, the available ASI-Zn was lower than 1 mg Zn/L, and then the optimum application rate of Zn fertilizer was about 20 kg Zn/ha. 展开更多
关键词 Agro Services International method coastal alluvial soil RICE soil available zinc sufficiency index deficiency index fertilizer recommendation yield
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Multiproduct and multistage integrated production planning model and algorithm based on an available production capacity network 被引量:3
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作者 Zhi-min Lü Tian-ru Jiang Zai-wei Li 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2021年第8期1343-1352,共10页
This research attempts to devise a multistage and multiproduct short-term integrative production plan that can dynamically change based on the order priority and virtual occupancy for application in steel plants. Cons... This research attempts to devise a multistage and multiproduct short-term integrative production plan that can dynamically change based on the order priority and virtual occupancy for application in steel plants. Considering factors such as the delivery time, varietal compatibility between different products, production capacity of variety per hour, minimum or maximum batch size, and transfer time, we propose an available production capacity network with varietal compatibility and virtual occupancy for enhancing production plan implementation and quick adjustment in the case of dynamic production changes. Here available means the remaining production capacity after virtual occupancy.To quickly build an available production capacity network and increase the speed of algorithm solving, constraint selection and cutting methods with order priority were used for model solving. Finally, the genetic algorithm improved with local search was used to optimize the proposed production plan and significantly reduce the order delay rate. The validity of the proposed model and algorithm was numerically verified by simulating actual production practices. The simulation results demonstrate that the model and improved algorithm result in an effective production plan. 展开更多
关键词 short-term integrated plan constraint satisfaction model available production capacity varietal compatibility virtual capacity occupancy
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China First Discovered Massive Available Hot Dry Rock Resources 被引量:2
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作者 HAO Ziguo FEI Hongcai +1 位作者 HAO Qingqing LIU Lian 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2015年第3期1039-1040,共2页
Hot Dry Rock (HDR) refers to those generally deeply buried impermeable metamorphic or crystallized biotite gneiss, granite and granodiorite rock bodies, with a burial depth greater than 2000 m, containing no water o... Hot Dry Rock (HDR) refers to those generally deeply buried impermeable metamorphic or crystallized biotite gneiss, granite and granodiorite rock bodies, with a burial depth greater than 2000 m, containing no water or vapor. HDR is as implied, hot and dry, with temperatures ranging from 150 to 650℃, and it can be utilized as a heat resource. Because this type of heat system does not require porosity, permeability and fluids and is widespread at the drillable depth range of 10 kin, it is thereby an infinite resource type. By contrast, thermal power generation results in copious pollution; wind power is irregular and unstable; solar energy occupies large areas. 展开更多
关键词 HDR China First Discovered Massive available Hot Dry Rock Resources ROCK
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Study on melting available silicone from coal gangue 被引量:3
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作者 HOU Chen-tao WANG Sheng-quan XIE Xiao-fei 《Journal of Coal Science & Engineering(China)》 2009年第4期426-429,共4页
Available silicone was melted from coal gangue samples from Hancheng diggings through calcination, digestion, and other means. The best calcination temperaturewas determined from a range of 550-1150^(。)C; and the bes... Available silicone was melted from coal gangue samples from Hancheng diggings through calcination, digestion, and other means. The best calcination temperaturewas determined from a range of 550-1150^(。)C; and the best time, from a range of 0.5-5 hby colorimetry method. The proper ratio of coal gangue, limestone, sodium carbonate, andcaustic soda was then determined through orthogonal experiment. The results show thatthe proper extraction condition for available silicone is the ratio of coal gangue, limestone,sodium carbonate, and caustic soda at 1:0.5:0.1:0.05, calcination temperature at 700^(。)C,and calcination time at 2 h. In this condition, the available silicone content can be morethan 19.65%. 展开更多
关键词 煤矸石 石硅 熔化 焙烧温度 焙烧时间 正交试验 提取条件 石灰石
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Effects of Long-term Located Fertilization on Evolution of Available Phosphorus and Phosphorus Pool in Shandong Fluvo-aquic Soil 被引量:1
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作者 yingpeng zhang gang duan +6 位作者 cuiping sun ziwen zhong ming sun yongping jing jiafa luo luji bo yan li 《Agricultural Biotechnology》 CAS 2018年第2期74-80,共7页
This study was conducted to investigate the effects of long-term located fertilization on soil phosphorus,the changes of soil available phosphorus( OlsenP),the evolution of soil total phosphorus( TP) and the ratio... This study was conducted to investigate the effects of long-term located fertilization on soil phosphorus,the changes of soil available phosphorus( OlsenP),the evolution of soil total phosphorus( TP) and the ratio change of Olsen-P to TP( PAC) by 33-year fertilization experiments in winter wheat-summer maize rotation system in Shandong fluvo-aquic soil. Eight treatments were designed as no fertilization( CK),nitrogen fertilizer( N),nitrogen and phosphate fertilizer( NP),nitrogen and potassium fertilizer( NK),phosphate and potassium fertilizer( PK),nitrogen-phosphate-potassium fertilizer( NPK),reduced NPK fertilizer( N(15) PK),and increased NPK fertilizer( N(25) PK). Meanwhile,eight organic fertilizer-added treatments were designed based on the application of inorganic fertilizer the same as the above ones. The results showed that TP,Olsen-P and PAC of treatments added with organic fertilizer were higher than those without organic fertilizer,and those of the treatments applied with phosphate fertilizer were higher than those of no phosphate fertilizer. With the increase of years,soil P pool decreased due to crop absorption,nutrient loss and morphological transformation and other causes under the treatments of without and only phosphate fertilizer,while remained stable under the treatments added with organic fertilizer. The PAC values were generally lower in fluvo-aquic soil,and it could be improved by the application of organic fertilizer. On the whole,the application of chemical phosphate fertilizer combined with organic fertilizer could improve the phosphorus content in soil and ensure the supply of phosphorus nutrition. This study would provide scientific basis for fertilization management and soil fertility in fluvo-aquic soil. 展开更多
关键词 Long-term located fertilization Fluvo-aquic soil Total phosphorus available phosphorus Phosphorus pool Activity coefficientHome
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Analyzing the Characteristics and Available Attributes of Skarn Gold Deposit Tailings
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作者 CHENG Yun-hong HUANG Fei +3 位作者 LI Guang-lu YANG Qing-yu HAN Peng LIU Rui 《矿物学报》 CAS CSCD 北大核心 2013年第S1期14-14,共1页
Skarn gold deposit tailings is a kind of tailings which is difficult to be utilized effectively. Taking a skarn gold deposit tailings from Hubei province, in China, as an example, the paper has tested and analyzed the... Skarn gold deposit tailings is a kind of tailings which is difficult to be utilized effectively. Taking a skarn gold deposit tailings from Hubei province, in China, as an example, the paper has tested and analyzed the tailings, and studied the characteristics and available attributes of the tailings, and provided scientific and efficient utilization approaches of tailings in the area of building materials further. The results showed that major mineral phases in the tailings is quartz, particle sizes of the tailings mainly exist in 10–100 μm, and the tailings has no pozzolanic activity. As a result, this kind of tailings can be used for building sand, and can be used as supplementary cementing material of concrete based on 展开更多
关键词 SKARN GOLD DEPOSIT TAILINGS available attributes
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