期刊文献+
共找到44篇文章
< 1 2 3 >
每页显示 20 50 100
Physiological basis for the differences of productive capacity among tillers in winter wheat 被引量:7
1
作者 XU Hai-cheng CAI Tie +1 位作者 WANG Zhen-lin HE Ming-rong 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2015年第10期1958-1970,共13页
The quality or structure of a wheat population is significantly affected by the compositions of tillers. Little has been known about the physiological basis for the differences of productive capacity among tillers. Tw... The quality or structure of a wheat population is significantly affected by the compositions of tillers. Little has been known about the physiological basis for the differences of productive capacity among tillers. Two winter wheat cultivars, Shannong 15(SN15) and Shannong 8355(SN8355), were used to investigate the differences of productive capacity among tillers and analyze the physiological mechanisms that determine the superior tiller group. Low-position tillers(early initiated tillers) had a higher yield per spike than high-position tillers(late initiated tillers) in both cultivars, which was due to their more grain number per spike, more fertile spikelet per spike, less sterile spikelet per spike and higher grain weight. According to cluster analysis, tillers of SN15 were classified into 2 groups: superior tiller group including main stem(0), the first primary tiller(I) and the second primary tiller(II); and inferior tiller group including the third primary tiller(III) and the first secondary tiller(I-p). Tillers of SN8355 were classified into 3 groups: superior tiller group(0 and I), intermediate tiller group(II and III) and inferior tiller group(I-p). In comparison with other tiller groups, the superior tiller group had higher photosynthetic rate of flag leaves, higher antioxidant enzyme(SOD, POD and CAT) activities and lower levels of lipid peroxidation in leaves, higher grain filling rate in both superior and inferior grains during grain filling, higher single-stem biological yield and larger single-stem economic coefficient. Correlation analysis showed that yield per spike was positively and significantly correlated with the flag leaf photosynthetic rate, grain filling rate, the antioxidant enzyme activities and soluble protein content(except for SN15 at 5 days post-anthesis(DPA)) of flag leaf, the single-stem biological yield, and the single-stem economic coefficient. Remarkable negative correlation was also found between yield per spike and MDA content of flag leaf. These results suggested that superior tiller group had stronger leaf photosynthetic capacity, more predominance in terms of grain filling, slower senescence rate, higher biological yield and larger economic coefficient, and therefore, showed greater productive capacity than other tiller groups. 展开更多
关键词 enzyme activities grain filling photosynthetic rate productive capacity TILLERS wheat(Triticum aestivum L.)
下载PDF
Production Capacity Prediction Method of Shale Oil Based on Machine Learning Combination Model
2
作者 Qin Qian Mingjing Lu +3 位作者 Anhai Zhong Feng Yang Wenjun He Min Li 《Energy Engineering》 EI 2024年第8期2167-2190,共24页
The production capacity of shale oil reservoirs after hydraulic fracturing is influenced by a complex interplay involving geological characteristics,engineering quality,and well conditions.These relationships,nonlinea... The production capacity of shale oil reservoirs after hydraulic fracturing is influenced by a complex interplay involving geological characteristics,engineering quality,and well conditions.These relationships,nonlinear in nature,pose challenges for accurate description through physical models.While field data provides insights into real-world effects,its limited volume and quality restrict its utility.Complementing this,numerical simulation models offer effective support.To harness the strengths of both data-driven and model-driven approaches,this study established a shale oil production capacity prediction model based on a machine learning combination model.Leveraging fracturing development data from 236 wells in the field,a data-driven method employing the random forest algorithm is implemented to identify the main controlling factors for different types of shale oil reservoirs.Through the combination model integrating support vector machine(SVM)algorithm and back propagation neural network(BPNN),a model-driven shale oil production capacity prediction model is developed,capable of swiftly responding to shale oil development performance under varying geological,fluid,and well conditions.The results of numerical experiments show that the proposed method demonstrates a notable enhancement in R2 by 22.5%and 5.8%compared to singular machine learning models like SVM and BPNN,showcasing its superior precision in predicting shale oil production capacity across diverse datasets. 展开更多
关键词 Shale oil production capacity data-driven model model-driven method machine learning
下载PDF
Creation of Cultivars with High Productive Tillering Capacity and Synchronous Earing for Ridge Technology Cultivation
3
作者 E. D. Bogdanova K. Kh. Makhmudova 《Journal of Agricultural Science and Technology(B)》 2011年第3期458-462,共5页
For cultivation of new common wheat cultivars having valuable morphological traits new resource-saving ridge technology was applied. Our collection of dwarf lines, obtained in the result of cyclical diallel crossings ... For cultivation of new common wheat cultivars having valuable morphological traits new resource-saving ridge technology was applied. Our collection of dwarf lines, obtained in the result of cyclical diallel crossings of genotrophs, induced by pyridine carbonic acids, zoned common wheat cultivars and short stem common wheat samples from the World Wide Collection of the Russian Institute of Plant Industry, was applied for creation of new common wheat lines having valuable morphological traits. It was observed that open blooming dwarfs were good for cross-pollination, and without insulation they demonstrated a great issue of natural hybrids. It was marked that cross-pollination promoted appearance of great number of hybrid plants with high productive tillering capacity. After individual selection among those hybrid plants and their propagation we got fertile constant lines of common winter wheat having 17-20 productive stems per one plant and a productive ear. These lines are firm and resistant to lodging. At the present time these constant lines are cultivated in conditions of resource-saving ridge technology. 展开更多
关键词 Ridge technology common wheat high productive tillering capacity.
下载PDF
A new method to evaluate integrated production system capacity in oil fields
4
作者 YADUA Asekhame U. LAWAL Kazeem A. 《Petroleum Exploration and Development》 SCIE 2023年第3期665-674,共10页
To improve the design and management of an integrated production system(IPS),a set of mathematical models and workflows are developed for evaluating the capacity of an IPS at steady-state conditions.Combining the cons... To improve the design and management of an integrated production system(IPS),a set of mathematical models and workflows are developed for evaluating the capacity of an IPS at steady-state conditions.Combining the conservation laws with applicable multiphase fluid and choke models,these mathematical models are solved to characterize the hydraulics of an integrated system of reservoir,wells,chokes,flowlines,and separator at steady state.The controllable variables such as well count,choke size and separator pressure are adjusted to optimize the performance of the IPs at a specific time.It is found that increasing the well count can increase the bulk flow rate of the production network,but too many wells may increase the manifold pressure,leading to decline of single-well production.Increasing the choke size can improve the capacity of the IPs.The production of the IPs is negatively correlated with the separator pressure.With increasing separator pressure and decreasing choke size,the increment of total fluid production(the capacity of IPS)induced by increasing well count decreases.Validation tests with field examples show a maximum absolute deviation is 1.5%,demonstrating the robustness and validity of the proposed mathematical models and workflows. 展开更多
关键词 integrated production system modelling integrated production system capacity productivity evaluation production optimization nodal analysis
下载PDF
Analysis of petrophysical cutoffs of reservoir intervals with production capacity and with accumulation capacity in clastic reservoirs 被引量:4
5
作者 Wang Yanzhong Cao Yingchang +3 位作者 Song Guoqi Song Ling Yang Tian Zhang Shaomin 《Petroleum Science》 SCIE CAS CSCD 2014年第2期211-219,共9页
Methodologies have been developed for calculating cutoffs of reservoir intervals with production capacity (RIPC) and reservoir intervals with accumulation capacity (RIAC) according to the types of pore throat stru... Methodologies have been developed for calculating cutoffs of reservoir intervals with production capacity (RIPC) and reservoir intervals with accumulation capacity (RIAC) according to the types of pore throat structures and dynamic force by using data from petrophysical analysis, production tests and mercury injection. The data are from clastic reservoirs in the third member (Es3) and the fourth member (Es4) of the Shahejie Formation in the Shengtuo area on the North Slope of the Dongying Sag, Jiyang Depression, China. The method of calculating cutoffs of RIPC is summarized as follows: 1) determination of permeability cutoffs of RIPC; 2) classification of types of pore-throat structures according to mercury injection data and then relating porosity to permeability and determining the relationship between porosity and permeability according to each type of pore-throat structure; and 3) calculating porosity cutoffs of RIPC using established correlation between porosity and permeability according to the type of pore throat structure. The method of calculating cutoffs of RIAC includes: 1) establishing a functional relationship between oil-water interracial tension and formation temperature; 2) calculating limiting values of maximum connected pore-throat radii according to formation temperature and dynamic forces of each reservoir interval; 3) correlating permeability with maximum connected pore-throat radius and then obtaining permeability cutoffs of RIAC; and 4) calculating porosity cutoffs on the basis of permeability cutoffs according to specific correlations, suitable for the type of porethroat structure. The results of this study show that porosity and permeability cutoffs of clastic reservoirs decrease with depth. For a fixed permeability cutoff, the porosity cutoff of R1PC varies because the type of pore throat is different. At a fixed temperature, porosity and permeability cutoffs of RIAC decrease as dynamic force increases. For a fixed permeability cutoff of effective hydrocarbon accumulation, the porosity cutoff also varies with different types of pore throat. 展开更多
关键词 Effective reservoir petrophysical cutoff of reservoir intervals with production capacity(RIPC) petrophysical cutoff of reservoir intervals with accumulation capacity (RIAC) clastic rocks
下载PDF
Multiproduct and multistage integrated production planning model and algorithm based on an available production capacity network 被引量:3
6
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
下载PDF
Impairment of IFN-a production capacity in patients with hepatitis C virus and the risk of the development of hepatocellular carcinoma 被引量:3
7
作者 Kazuko Uno Yoshiki Suginoshita +4 位作者 Kazuhiro Kakimi Fuminori Moriyasu Mayumi Hirosaki Taro Shirakawa Tsunataro Kishida 《World Journal of Gastroenterology》 SCIE CAS CSCD 2005年第46期7330-7334,共5页
AIM: To determine the utility of interferon (IFN) -αproduction capacity in patients with hepatitis C virus (HCV) infection for the measurement of immunosurveillance potential and for the early detection of hepatocell... AIM: To determine the utility of interferon (IFN) -αproduction capacity in patients with hepatitis C virus (HCV) infection for the measurement of immunosurveillance potential and for the early detection of hepatocellular carcinoma (HCC) by investigating the Sendai virus (HVJ) stimulated IFN-α production capacity of patients with HCV infection.METHODS: HVJ stimulated IFN-α production was determined in a large number of patients with HCV infection and the development of HCC was monitored for 3 years in patients with liver cirrhosis (LC).RESULTS: IFN-α production capacity decreases gradually with the progression of liver disease from chronic hepatitis (CH) to HCC. A significant correlation between the duration of HCV infection and impaired IFN-α production capacity was observed. IFN-α production in patients who developed HCC within 3 years was significantly lower than that of patients who remained in LC without developing HCC.CONCLUSION: Measurement of IFN-α production in LC patients may be useful for the early detection of HCC. 展开更多
关键词 IFN-α production capacity Hepatitis C virus Hepatocellular carcinoma
下载PDF
Formation of methane hazard in longwall coal mines with increasingly higher production capacity 被引量:2
8
作者 Krause Eugeniusz Skiba Jacek 《International Journal of Mining Science and Technology》 SCIE EI 2014年第3期403-407,共5页
Increasingly higher hard coal production capacity in Upper Silesian Coal Basin(Poland) in the last two decades led to significant increase of methane hazard occurrence in the workings of exploitation areas.An increase... Increasingly higher hard coal production capacity in Upper Silesian Coal Basin(Poland) in the last two decades led to significant increase of methane hazard occurrence in the workings of exploitation areas.An increase of methane content in the exploited seams and in the surrounding strata, associated with increasing depth of mining, results in higher methane emission into the longwall areas from exploited seams and degassing seams in the mining-induced de-stressed zone. Operational experience gained by the collieries confirms that reducing methane release during longwall operations often requires decreasing operating speed of a shearer in a shift. The paper presents an analysis of the parameters and factors,which have critical influence on the formation of methane hazard in longwall areas with high production capacity. 展开更多
关键词 Methane hazard Labour safety Production capacity Methane emission
下载PDF
Actuality and Influencing Factors of Integrated Production Capacity of Foodstuff in Heilongjiang Province 被引量:3
9
作者 Zhou Hui-qiu Zhang De-hua 《Journal of Northeast Agricultural University(English Edition)》 CAS 2012年第1期82-90,共9页
Heilongjiang Province is an important marketable grain depot in China. Since the reform and opening up, Heilongjiang Province production capacity of foodstuff is increasingly growing into a new level. This paper start... Heilongjiang Province is an important marketable grain depot in China. Since the reform and opening up, Heilongjiang Province production capacity of foodstuff is increasingly growing into a new level. This paper started with the actuality of Heilongjiang Province integrated production capacity of foodstuff, and analyzed its major factors empirically through the mathematical model, then proposed some measures to enhance Heilongjiang Province production capacity of foodstuff which ensured China foodstuff security 展开更多
关键词 Heilongjiang Province integrated foodstuff production capacity influencing factor
下载PDF
Study on the driving factors and regulation mode for coal production capacity 被引量:1
10
作者 Wen-Sheng Wang Jing-Jing Zhang 《Petroleum Science》 SCIE CAS CSCD 2021年第5期1564-1577,共14页
Coal production capacity regulation is a complex system involving economic growth,structural optimization,high-efficiency mining,and environmental protection.Based on its driving factors,this paper forms four regulati... Coal production capacity regulation is a complex system involving economic growth,structural optimization,high-efficiency mining,and environmental protection.Based on its driving factors,this paper forms four regulation modes representing different control orientations,establishes a system dynamics model,and predicts the regulation effects of single-factor and combined control mode.The result shows:(1) Except for the mechanization degree and recovery rate,the other nine individual production capacity control policies are all conducive to reducing coal production capacity and restraining the excessive growth of coal production capacity.(2) The effect of combined regulation mode on slowing down the growth of coal demand,regulating the excessive growth of coal production capacity and new capacity investment are obviously better than that of single policy.(3) The combined control modes have obvious differences in the suppression effect on coal production capacity:transformational development mode > technology-driven mode > structural optimization mode > efficiency improvement mode.Therefore,in the process of achieving optimal regulation of coal production capacity,attention should be paid to the preferential use of transformational development and technology-driven mode.At the same time,the comprehensive use of regulation and control methods should also be considered to improve the regulation effect and the regulation efficiency of coal production capacity. 展开更多
关键词 Coal production capacity Regulation mode Driving factors System dynamics model
下载PDF
Exploiting Virtual Elasticity of Production Systems for Respecting OTD-Part 1: Post-Optimality Conditions for Ergodic Order Arrivals in Fixed Capacity Regimes 被引量:2
11
作者 Bruno G. Rüttimann Martin T. Stöckli 《American Journal of Operations Research》 2020年第6期321-342,共22页
Respecting the on-time-delivery (OTD) for manufacturing orders is mandatory. This depends, however, on the probability distribution of incoming order rate. The case of non-equal distribution, such as aggregated arriva... Respecting the on-time-delivery (OTD) for manufacturing orders is mandatory. This depends, however, on the probability distribution of incoming order rate. The case of non-equal distribution, such as aggregated arrivals, may compromise the observance of on-time supplies for some orders. The purpose of this paper is to evaluate the conditions of post-optimality for stochastic order rate governed production systems in order to observe OTD. Instead of a heuristic or a simulative exploration, a Cartesian-based approach is applied to developing the necessary and sufficient mathematical condition to solve the problem statement. The research result demonstrates that increasing </span><span style="font-family:Verdana;">speed of throughput reveals a latent capacity, which allows arrival orders </span><span style="font-family:Verdana;">above capacity limits to be backlog-buffered and rescheduled for OTD, exploiting the virtual manufacturing elasticity inherent to all production systems to increase OTD reliability of non JIT-based production systems. 展开更多
关键词 On-Time-Delivery Production System Lean Manufacturing Industry 4.0 Arrival Rate Markovian Arrival Distribution Production Backlog Manufacturing Elasticity Production capacity Bottle Neck Break-Even Point Optimal Production Volume Ergodic Processes
下载PDF
Evaluation of Integrated Production Capacity of Well- facilitated Farmland in Jiangsu Province 被引量:1
12
作者 Qian ZHUANG 《Asian Agricultural Research》 2016年第12期60-65,共6页
The fundamental task of well-facilitated farmland construction is to continuously lift the integrated production capacity. External project construction for well-facilitated farmland can not completely solve existing ... The fundamental task of well-facilitated farmland construction is to continuously lift the integrated production capacity. External project construction for well-facilitated farmland can not completely solve existing problems in improvement of intrinsic quality of farmland.Based on research findings of integrated production capacity of farmland,starting from basic elements such as water,soil,seed,fertilizer,and pesticide,this paper introduced factors influencing the integrated production capacity of well-facilitated farmland,including natural quality of farmland,supporting infrastructure,agricultural technology level and management level,and labor quality. Besides,it establish an evaluation system for integrated production capacity of well-facilitated farmland in Jiangsu Province by Analytic Hierarchy Process( AHP),and made an empirical study using indicator data of 2010- 2014. Results indicated that the general index of integrated production capacity of farmland in Jiangsu Province in 2010- 2014 was ascending,reflecting improvement of integrated production capacity of farmland. With the aid of radar map,it further found that the coupling between water,soil,seed,fertilizer,and pesticide and other elements play a crucial role in lifting the integrated production capacity of farmland. Finally,based on existing problems in construction of well-facilitated farmland in Jiangsu Province,it came up with some pertinent recommendations from the perspective of coordinated development of all elements. 展开更多
关键词 Well-facilitated farmland Integrated production capacity Analytical hierarchy process(AHP)
下载PDF
Current Situation and Approaches Relating to Construction of Agricultural Production and Operation Development Capacity for Rural Households in Hubei Province
13
作者 Jing ZENG 《Asian Agricultural Research》 2018年第6期18-22,共5页
The main body of household operation in the rural household contract responsibility system of our country has developed to the present stage,and has formed the situation that three kinds of rural households coexist,na... The main body of household operation in the rural household contract responsibility system of our country has developed to the present stage,and has formed the situation that three kinds of rural households coexist,namely,ordinary rural households,major professional households and family farms. The agricultural production and operation of three kinds of household plays an important role in supporting the rapid development of modern agriculture in China. Under the new situation of deepening the rural reform and realizing the goal of well-off society in an all-round way,it is of great practical significance to make a thorough investigation and study on the present situation and approaches relating to the construction of the agricultural production and operation capacity for the three kinds of rural households. 展开更多
关键词 Rural households Agricultural production and operation development capacity Analysis of current situation Construction approaches
下载PDF
China's Excess Oil Refining Production Capacity in the Background of the Supply Side Structural Reform
14
作者 Wang Zhen Zhang Yuxuan 《China Oil & Gas》 CAS 2018年第3期43-51,共9页
Through analysis of the current situation and newly-increased production capacity-of the oil refining industry of China, this Paper discusses both the continuous expansion trend and the serious excess of production ca... Through analysis of the current situation and newly-increased production capacity-of the oil refining industry of China, this Paper discusses both the continuous expansion trend and the serious excess of production capacity of the oil refining industry of China. Due to the entry of the Chinese economy into the new normal,the accelerated substitution of old energy by new energy and rigid restrictions composed of low carbon and environmental protection requirements, the oil demand of China will continue to increase overall, but the growth will obviously slow down. At the same time, the newly-increased production capacity in Shandong and coastal region will continuously expand, the supply and demand contradiction will intensify, and the structural excess production capacity of the oil refining industry of China will be prominent. It is suggested that the government should attach great importance to the production capacity of the oil refining industry at the macro level, and deeply carry forward the supply side structural reform, and that enterprises should speed up technical innovation,enhance regional and layout optimization, adapt to market changes and adjust product structure, control oil refining but increase chemical engineering, improve product quality and production efficiency, and constantly promote the international competitiveness of the Chinese petrochemical industry. 展开更多
关键词 Oil refining production capacity Oil demand Supply side structural reform
下载PDF
CNPC Refineries' Production Capacity in 1996
15
《China Oil & Gas》 CAS 1997年第2期125-125,共1页
关键词 CNPC Refineries Production capacity in 1996
下载PDF
CNPC Refineries' Production Capacity in 1997
16
《China Oil & Gas》 CAS 1998年第2期120-120,共1页
关键词 CNPC Refineries Production capacity in 1997
下载PDF
China's Industrial Capacity Utilization:Sectoral Comparison,Regional Differences and Determinants
17
作者 梁泳梅 董敏杰 张其仔 《China Economist》 2016年第2期109-127,共19页
Using provincial-level data, this paper has estimated capacity utilization, technical efficiency and equipment utilization for China's industrial sectors, conducted a comparative analysis of capacity utilization a... Using provincial-level data, this paper has estimated capacity utilization, technical efficiency and equipment utilization for China's industrial sectors, conducted a comparative analysis of capacity utilization across various sectors, provinces, municipalities and autonomous regions, and discussed the determinants of capacity utilization. We have reached the following conclusions:(1) China's average industrial capacity utilization stood at 69.3% between 2001 and 2011, rising for most of the time before 2008 and generally declining afterwards;(2) among the two sources of capacity utilization, equipment utilization is lower than technical efficiency and constitutes a major factor affecting capacity utilization, yet technical efficiency has demonstrated a significant trend of decline in recent years;(3) at the industry level, industrial capacity utilization is generally high for light industries such as textiles while generally low for mining, public utilities and heavy industries in manufacturing;(4) at the regional level, capacity utilization, technical efficiency and equipment utilization are much higher in the eastern region than in the other regions, where the levels are relatively close to each other;(5) economic growth and the level of market-based operation have a significant positive correlation with capacity utilization, while industry capital intensity, the share of output value from SOEs and local government investment intensity have a significant negative correlation with capacity utilization. 展开更多
关键词 production capacity capacity utilization technical efficiency equipmentutilization data envelopment analysis (DEA)
下载PDF
“Extreme utilization” theory and practice in gas storages with complex geological conditions 被引量:1
18
作者 MA Xinhua ZHENG Dewen +1 位作者 DING Guosheng WANG Jieming 《Petroleum Exploration and Development》 SCIE 2023年第2期419-432,共14页
Based on more than 20-year operation of gas storages with complex geological conditions and a series of research findings, the pressure-bearing dynamics mechanism of geological body is revealed. With the discovery of ... Based on more than 20-year operation of gas storages with complex geological conditions and a series of research findings, the pressure-bearing dynamics mechanism of geological body is revealed. With the discovery of gas-water flowing law of multi-cycle relative permeability hysteresis and differential utilization in zones, the extreme utilization theory targeting at the maximum amount of stored gas, maximum injection-production capacity and maximum efficiency in space utilization is proposed to support the three-in-one evaluation method of the maximum pressure-bearing capacity of geological body, maximum well production capacity and maximum peak shaving capacity of storage space. This study realizes the full potential of gas storage(storage capacity) at maximum pressure, maximum formation-wellbore coordinate production, optimum well spacing density match with finite-time unsteady flow, and peaking shaving capacity at minimum pressure, achieving perfect balance between security and capacity. Operation in gas storages, such as Hutubi in Xinjiang, Xiangguosi in Xinan, and Shuang6 in Liaohe, proves that extreme utilization theory has promoted high quality development of gas storages in China. 展开更多
关键词 underground gas storage gas-storage geological body maximum pressure-bearing maximum well production capacity maximum peak shaving capacity extreme utilization theory multi-cycle relative permeability hysteresis
下载PDF
Promoting the Empowerment of Science and Technology to Ensure Food Safety Production:A Case Study of Huizhou City
19
作者 Liqing WANG Cijizhuoma Zhenchang LIU 《Asian Agricultural Research》 2023年第1期8-9,12,共3页
The current situation of grain production in Huizhou City was analyzed firstly,and then the existing problems and challenges of grain safety production were pointed out,such as increases in the pressure to ensure grai... The current situation of grain production in Huizhou City was analyzed firstly,and then the existing problems and challenges of grain safety production were pointed out,such as increases in the pressure to ensure grain safety production and the difficulty of stable development of grain production.Finally,several countermeasures and suggestions for the stable development of grain production were put forward. 展开更多
关键词 Food security Huizhou City Science and technology Grain production capacity
下载PDF
In-situ stress of coal reservoirs in the Zhengzhuang area of the southern Qinshui Basin and its effects on coalbed methane development
20
作者 Peng Zhang Ya Meng +4 位作者 Chaoying Liu Yuanling Guo Xiangbin Yan Lixue Cai Zhe Cheng 《Energy Geoscience》 2023年第2期17-27,共11页
In-situ stress is a critical factor influencing the permeability of coal reservoirs and the production capacity of coalbed methane(CBM)wells.Accurate prediction of in-situ stress and investigation of its influence on ... In-situ stress is a critical factor influencing the permeability of coal reservoirs and the production capacity of coalbed methane(CBM)wells.Accurate prediction of in-situ stress and investigation of its influence on coal reservoir permeability and production capacity are significant for CBM development.This study investigated the CBM development zone in the Zhengzhuang area of the Qinshui Basin.According to the low mechanical strength of coal reservoirs,this study derived a calculation model of the in-situ stress of coal reservoirs based on the multi-loop hydraulic fracturing method and analyzed the impacts of initial fractures on the calculated results.Moreover,by combining the data such as the in-situ stress,permeability,and drainage and recovery data of CBM wells,this study revealed the spatial distribution patterns of the current in-situ stress of the coal reservoirs and discussed the impacts of the insitu stress on the permeability and production capacity.The results are as follows.(1)Under given fracturing pressure,longer initial fractures are associated with higher calculated maximum horizontal principal stress values.Therefore,ignoring the effects of the initial fractures will cause the calculated values of the in-situ stress to be less than the actual values.(2)As the burial depth increases,the fracturing pressure,closure pressure,and the maximum and minimum horizontal principal stress of the coal reservoirs in the Zhengzhuang area constantly increase.The average gradients of the maximum and minimum horizontal principal stress are 3.17 MPa/100 m and 2.05 MPa/100 m,respectively.(3)Coal reservoir permeability is significantly controlled by the magnitude and state of the current in-situ stress.The coal reservoir permeability decreases exponentially with an increase in the effective principal stress.Moreover,a low lateral pressure coefficient(less than 1)is associated with minor horizontal compressive effects and high coal reservoir permeability.(4)Under similar conditions,such as resource endowments,CBM well capacity is higher in primary structural coal regions with moderate paleotectonic stress modification,low current in-situ stress,and lateral pressure coefficient of less than 1. 展开更多
关键词 In-situ stress Coal reservoir Multi-loop hydraulic fracturing method PERMEABILITY Production capacity
下载PDF
上一页 1 2 3 下一页 到第
使用帮助 返回顶部