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超临界CO_(2)强化页岩气开采技术研究现状及展望

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现代化工 2024年第3期44卷 16-20页

作者：杨国栋黄冕刘思雨马鑫王子未武汉科技大学资源与环境工程学院湖北武汉430081 中国地质调查局水文地质环境地质调查中心河北保定071051

介绍了页岩的储层特征,从页岩不同尺度渗流机理、CO_(2)/CH4竞争吸附原理及CO_(2)-水-页岩相互作用机理着手,分析了超临界CO_(2)在强化页岩气开采技术中的作用与优势,最后指出了超临界CO_(2)强化页岩气开采技术在技术经济性、设备研发... 详细信息

介绍了页岩的储层特征,从页岩不同尺度渗流机理、CO_(2)/CH4竞争吸附原理及CO_(2)-水-页岩相互作用机理着手,分析了超临界CO_(2)在强化页岩气开采技术中的作用与优势,最后指出了超临界CO_(2)强化页岩气开采技术在技术经济性、设备研发以及环境风险等方面面临的挑战。

关键词：超临界CO_(2) 页岩气渗流机理竞争吸附 scCO_(2)-ESGR

Resonance mechanism of flapping wing based on fluid structure interaction simulation

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Chinese Journal of Aeronautics 2024年第5期37卷 243-262页

作者： Yueyang guo Wenqing yang Yuanbo dong dong XUE National Key Laboratory of Science and Technology on Aerodynamic Design and Research School of AeronauticsNorthwestern Polytechnical UniversityXi'an 710072China Research&Development Institute of Northwestern Polytechnical University in Shenzhen Shenzhen 518063China yangtze River Delta Research Institute of Northwestern Polytechnical University Taicang 215400China

Certain insect species have been observed to exploit the resonance mechanism of their *** order to achieve resonance and optimize aerodynamic performance,the conventional approach is to set the flapping frequency of flexible wings based on the Traditional Structural Modal(TSM)***,there exists controversy among researchers regarding the relationship between frequency and aerodynamic *** that the structural response of wings can be influenced by the surrounding air vibrations,an analysis known as Acoustic Structure Interaction Modal(ASIM)is introduced to calculate the resonant *** this study,Fluid Structure Interaction(FSI)simulations are employed to investigate the aerodynamic performance of flapping wings at modal frequencies derived from both TSM and ASIM *** performance is evaluated for various mass ratios and frequency ratios,and the findings indicate that the deformation and changes in vortex structure exhibit similarities at mass ratios that yield the highest aerodynamic ***,the flapping frequency associated with the maximum time-averaged vertical force coefficient at each mass ratio closely aligns with the ASIM frequency,as does the frequency corresponding to maximum ***,the ASIM analysis can provide an effective means for predicting the optimal flapping frequency for flexible ***,it enables the prediction that flexible wings with varying mass ratios will exhibit similar deformation and vortex structure *** paper offers a fresh perspective on the ongoing debate concerning the resonance mechanism of Flexible Flapping Wings(FFWs)and proposes an effective methodology for predicting their aerodynamic performance.

关键词： Flexible Flapping Wing(FFW) Acoustic Structure Interaction Modal(ASIM) Fluid Structure Interaction(FSI) Resonance mechanism Aerodynamic performance

Influence of(FeO+Ti O_2) abundance on the microwave thermal emissions of lunar regolith

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Science China Earth Sciences 2016年第7期59卷 1498-1507页

作者： MENG Zhi guo yang guo dong PING Jin Song CAI Zhan Chuan Alexander GUSEV Edward M.OSEI College of Geoexploration Science and Technology Jilin University Key Laboratory of Planetary Sciences Chinese Academy of Sciences Key Laboratory of Lunar and Planetary Exploration Chinese Academy of Sciences Faculty of Information Technology Macao University of Science and Technology Institute of Geology Kazan Federal University Department of Geomatic Engineering Kwame Nkrumah University of Science and Technology

One of the essential controls on the microwave thermal emissions(MTE) of the lunar regolith is the abundance of Fe O and TiO_2, known as the(Fe O+Ti O_2) abundance(FTA). In this paper, a radiative transfer simulation is employed first to study the change in the brightness temperature(T_B) with FTA under a range of frequencies and surface temperatures. Then, we analyze the influence of FTA on the MTE of the lunar regolith using microwave sounder(CELMS) data from the Chang'E-2 lunar orbiter, Clementine UV-VIS data, and lunar samples recovered from the Apollo and Surveyor projects. We conclude that:(1) FTA strongly influences the MTE of the lunar regolith, but it is not the decisive control, and(2) FTA decreases slightly with depth. This research plays an essential role in appropriately inverting CELMS data to obtain lunar regolith parameters.

关键词： Lunar regolith Microwave thermal emission Radiative transfer simulation (FeO+TiO2) abundance CELMS data

Grain yield and nitrogen use efficiency of an ultrashort-duration variety grown under different nitrogen and seeding rates in direct-seeded and double-season rice in Central China

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Journal of Integrative Agriculture 2023年第4期22卷 1009-1020页

作者： WANG Xin-yu yang guo-dong XU Le XIANG Hong-shun yang Chen WANG Fei PENG Shao-bing National Key Laboratory of Crop Genetic Improvement/Hubei Hongshan Laboratory/Key Laboratory of Crop Ecophysiology and Farming System in the Middle Reaches of the yangtze River Ministry of Agriculture and Rural Affairs/College of Plant Science and TechnologyHuazhong Agricultural UniversityWuhan 430070P.R.China

Nitrogen(N) and seeding rates are important factors affecting grain yield and N use efficiency(NUE) in directseeded rice. However, these factors have not been adequately investigated on direct-seeded and double-season rice(DDR) in Central China. The objective of this study was to evaluate the effects of various N and seeding rates on the grain yield and NUE of an ultrashort-duration variety grown under DDR. Field experiments were conducted in 2018 in Wuxue County and 2019 in Qichun County, Hubei Province, China with four N rates and three seeding *** results showed that the grain yield of the ultrashort-duration variety ranged from 6.32 to 8.23 t ha–1with a total growth duration of 85 to 97 days across all treatments with N application. Grain yield was increased significantly by N application in most cases, but seeding rate had an inconsistent effect on grain yield. Furthermore, the response of grain yield to the N rates was much higher than the response to seeding rates. The moderate N rates of 100–150 and 70–120 kg N ha–1in the early and late seasons, respectively, could fully express the yield potential of the ultrashort-duration variety grown under DDR. Remarkably higher N responses and agronomic NUE levels were achieved in the early-season rice compared with the late-season rice due to the difference in indigenous soil N supply capacity(INS) between the two seasons. Seasonal differences in INS and N response should be considered when crop management practices are optimized for achieving high grain yield and NUE in ultrashort-duration variety grown under DDR.

关键词： direct-seeded and double-season rice grain yield nitrogen rate nitrogen use efficiency seeding rate

Border effects of the main and ratoon crops in the rice ratooning system

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Journal of Integrative Agriculture 2023年第1期22卷 80-91页

作者： ZHENG Chang WANG Yue-chao XU Wen-ba yang De-sheng yang guo-dong yang Chen HUANG Jian-liang PENG Shao-bing National Key Laboratory of Crop Genetic Improvement/Hubei Hongshan Laboratory/MARA Key Laboratory of Crop Ecophysiology and Farming Systems in the Middle Reaches of the yangtze River/College of Plant Science and Technology Huazhong Agricultural UniversityWuhan 430070P.R.China

The border effect(BE)is widely observed in crop field experiments,and it has been extensively studied in many ***,only limited attention has been paid to the BE of ratoon *** conducted field experiments on ratoon rice in Qichun County,Hubei Province,Central China in 2018 and 2019 to compare the BE in the main and ratoon crops,and to quantify the contribution of BE in the main crop to that in the ratoon *** BE of two hybrid varieties was measured for the outermost,second outermost,and third outermost rows in each plot of both *** determine the contribution of BE between the two crops,portions of hills in the outermost and second outermost rows were uprooted during the harvest of the main crop so that the second and third outermost rows then became the outermost rows in the ratoon ***,the BE on grain yield was greater in the main crop than in the ratoon *** the main crop,the BE on grain yield was 98.3%in the outermost row,which was explained by the BE on panicles m^(–2),spikelets/panicle,spikelets m^(–2),and total dry *** the ratoon crop,the BE on grain yield was reduced to 60.9 and 27.6%with and without the contribution of the BE in the main crop,***,55.1%of the BE on grain yield in the ratoon crop was contributed from the main *** stubble dry weight and non-structural carbohydrate(NSC)accumulation at the harvest of the main crop were responsible for the contribution of BE in the main crop to that in the ratoon *** results suggest that increases in stubble dry weight and NSC accumulation at the harvest of the main crop could be important strategies for developing high-yielding cropping practices in the rice ratooning system.

关键词： border effect grain yield non-structural carbohydrate ratoon rice

Grain yield and lodging-related traits of ultrashort-duration varieties for direct-seeded and double-season rice in Central China

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Journal of Integrative Agriculture 2022年第10期21卷 2888-2899页

作者： WANG Xin-yu XU Le LI Xiao-xiao yang guo-dong WANG Fei PENG Shao-bing National Key Laboratory of Crop Genetic Improvement/Hubei Hongshan Laboratory/Key Laboratory of Crop Ecophysiology and Farming System in the Middle Reaches of the yangtze River Ministry of Agriculture and Rural Affairs/College of Plant Science and TechnologyHuazhong Agricultural UniversityWuhan 430070P.R.China

Lodging is the most common constraint on grain yield of direct-seeded *** is limited information about lodging resistance and its related plant traits in direct-seeded and double-season rice(DDR)in Central *** study aims to identify the plant traits that achieve high lodging resistance in ultrashort-duration varieties(about 95 days)of *** experiments were conducted in 2017 and 2018 in Wuxue County,Hubei Province,China,with four ultrashort-duration varieties grown under two nitrogen(N)***-related traits were measured on the 15 th day after heading,and yield and yield attributes were measured at *** grain yield of the four varieties ranged from 4.59 to 7.61 t ha^(-1)across the two N rates,with a total growth duration of 85 to 97 *** differences in lodging index were mainly explained by the bending moment,which was closely related to plant *** resistance did not affect the lodging index *** plant height from 95.4 to 80.5 cm decreased the lodging index by 22.4%but did not reduce grain *** results suggested that reducing plant height was effective in improving the lodging resistance of ultrashort-duration varieties of *** resistance should be enhanced by improving breaking resistance rather than reducing plant height to increase DDR grain yield further.

关键词： direct seeding double-season rice lodging plant height ultrashort growth duration

Comparison of seven screening methods in the diagnosis of bladder cancer

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Chinese Medical Journal 2006年第21期119卷 1763-1771页

作者： SUN Yi HE Da-lin MA Qiang WAN Xing-yang ZHU guo-dong LI Lei LUO Yong HE Hui yang Lin Institute of Urology First Affiliated Hospital of Medical School Xi＇an Jiaotong University Xi＇an 710061 China

Background We compared the validity （evaluated by sensitivity and specificity）, reliability （evaluated by reproducibility） and yield （evaluated by predictive value, examining complexity and cost） of individual and combined tests for bladder tumour antigen stat （BTAstat）, nuclear matrix protein 22 （NMP22）, hyaluronic acid （HA）, survivin, CD44v6, vascular endothelial growth factor （VEGF）, and voided urine cytology （VUC） in detecting bladder cancer. And at the same time we evaluated the clinical value of these seven detecting methods in the diagnosis of bladder cancer. Methods The six markers and VUC were detected in the urine of cancer group （151 patients with bladder cancer） and two control groups （50 patients with benign urological diseases and 50 healthy controls）. The sensitivity, specificity, predictive value, reproducibility, examining complexity and checking cost of each marker and combined markers were calculated. Results There was a significant difference between bladder cancer group and the two control groups. The sensitivity, specificity and positive predictive value were as follows： VUC （36.4%, 100.0%, 100%）, BTAstat （76.8%, 87.0%, 89.9%）, NMP22 （77.5%, 81.0%, 86.0%）, HA （82.8%, 83.0%, 88.0%）, survivin （70.2%, 85.0%, 87.6%）, CD44v6 （50.3%, 79.0%, 78.4%）, and VEGF （68.2%, 93.0%, 93.6%）. The highest sensitivities were 91.4% for NMP22＋BTAstat and HA＋NMP22, whereas the combined marker with the lowest sensitivity （62.3%） was VUC＋CD44v6. The highest specificity was 93.0% for the combined use of VUC＋VEGF and HA＋CD44v6 had the lowest specificity （73.0%）. The most convenient examining method was the detection for BTAstat, the lowest cost was the detection for HA, and the best reproducibility were the detection for BTAstat and VUC. Conclusions All the markers have obvious clinical value in diagnosis of bladder cancer. The use of BTAstat＋HA or NMP22＋BTAstat are better examining methods in terms of validity, reliability, and yield.

关键词： tumour markers, biological bladder neoplasms urine diagnosis

The Responses of Morphological Trait,Leaf Ultrastructure,Photosynthetic and Biochemical Performance of Tomato to Differential Light Availabilities

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Agricultural Sciences in China 2011年第12期10卷 1887-1897页

作者： FU Qiu-shi ZHAO Bing WANG Xue-wen WANG Yu-jue REN Shu-xin guo yang-dong College of Agriculture ＆ Biotechnology China Agricultural University Beijing 100193 P.R. China School of Agriculture Virginia State University Petersburg VA23806 USA Department of Horticulture Cornell University Ithaca NY14853 USA

The whole-plant morphology, leaf ultrastructure, photosynthesis as well as enzyme activities of two tomato cultivars （Meifen-2 and Hongsheng） to differential light availabilities （450-500 gmol m-2 s-1, 75-100 gmol m-2 s^-1） were examined in controlled environment. The results showed that the plant biomass and root/shoot ratio decreased and the specific leaf area increased significantly under the low light condition. There was a significant increase in malondialdehyde （MDA） concentration, superoxide dismutase （SOD） and peroxidase （POD） activities and decrease in soluble sugar and protein contents in LL-grown plants. For both cultivars, downregulation of photosynthesis and electron transport components were observed in LL-grown plants, the inhibition of the photosynthesis under the LL condition could be partially explained by the decrease of stomata density and by the changes of chloroplast.

关键词： chlorophyll fluorescence chloroplast photosynthesis stomata tomato

Oilfield analogy and productivity prediction based on machine learning: Field cases in PL oilfield, China

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Petroleum Science 2024年第4期21卷 2554-2570页

作者： Wen-Peng Bai Shi-Qing Cheng Xin-yang guo yang Wang Qiao guo Chao-dong Tan State Key Laboratory of Petroleum Resources and Engineering China University of Petroleum (Beijing)

In the early time of oilfield development, insufficient production data and unclear understanding of oil production presented a challenge to reservoir engineers in devising effective development plans. To address this challenge, this study proposes a method using data mining technology to search for similar oil fields and predict well productivity. A query system of 135 analogy parameters is established based on geological and reservoir engineering research, and the weight values of these parameters are calculated using a data algorithm to establish an analogy system. The fuzzy matter-element algorithm is then used to calculate the similarity between oil fields, with fields having similarity greater than 70% identified as similar oil fields. Using similar oil fields as sample data, 8 important factors affecting well productivity are identified using the Pearson coefficient and mean decrease impurity（MDI） method. To establish productivity prediction models, linear regression（LR）, random forest regression（RF）, support vector regression（SVR）, backpropagation（BP）, extreme gradient boosting（XGBoost）, and light gradient boosting machine（Light GBM） algorithms are used. Their performance is evaluated using the coefficient of determination（R2）, explained variance score（EV）, mean squared error（MSE）, and mean absolute error（MAE） metrics. The Light GBM model is selected to predict the productivity of 30 wells in the PL field with an average error of only 6.31%, which significantly improves the accuracy of the productivity prediction and meets the application requirements in the field. Finally, a software platform integrating data query,oil field analogy, productivity prediction, and knowledge base is established to identify patterns in massive reservoir development data and provide valuable technical references for new reservoir development.

关键词： Data mining technique Analogy parameters Oilfield analogy Productivity prediction Software platform