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Regression analysis and its application to oil and gas exploration:A case study of hydrocarbon loss recovery and porosity prediction,China
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作者 Yang Li Xiaoguang Li +3 位作者 Mingyu Guo Chang Chen Pengbo Ni Zijian Huang 《Energy Geoscience》 EI 2024年第4期240-252,共13页
In oil and gas exploration,elucidating the complex interdependencies among geological variables is paramount.Our study introduces the application of sophisticated regression analysis method at the forefront,aiming not... In oil and gas exploration,elucidating the complex interdependencies among geological variables is paramount.Our study introduces the application of sophisticated regression analysis method at the forefront,aiming not just at predicting geophysical logging curve values but also innovatively mitigate hydrocarbon depletion observed in geochemical logging.Through a rigorous assessment,we explore the efficacy of eight regression models,bifurcated into linear and nonlinear groups,to accommodate the multifaceted nature of geological datasets.Our linear model suite encompasses the Standard Equation,Ridge Regression,Least Absolute Shrinkage and Selection Operator,and Elastic Net,each presenting distinct advantages.The Standard Equation serves as a foundational benchmark,whereas Ridge Regression implements penalty terms to counteract overfitting,thus bolstering model robustness in the presence of multicollinearity.The Least Absolute Shrinkage and Selection Operator for variable selection functions to streamline models,enhancing their interpretability,while Elastic Net amalgamates the merits of Ridge Regression and Least Absolute Shrinkage and Selection Operator,offering a harmonized solution to model complexity and comprehensibility.On the nonlinear front,Gradient Descent,Kernel Ridge Regression,Support Vector Regression,and Piecewise Function-Fitting methods introduce innovative approaches.Gradient Descent assures computational efficiency in optimizing solutions,Kernel Ridge Regression leverages the kernel trick to navigate nonlinear patterns,and Support Vector Regression is proficient in forecasting extremities,pivotal for exploration risk assessment.The Piecewise Function-Fitting approach,tailored for geological data,facilitates adaptable modeling of variable interrelations,accommodating abrupt data trend shifts.Our analysis identifies Ridge Regression,particularly when augmented by Piecewise Function-Fitting,as superior in recouping hydrocarbon losses,and underscoring its utility in resource quantification refinement.Meanwhile,Kernel Ridge Regression emerges as a noteworthy strategy in ameliorating porosity-logging curve prediction for well A,evidencing its aptness for intricate geological structures.This research attests to the scientific ascendancy and broad-spectrum relevance of these regression techniques over conventional methods while heralding new horizons for their deployment in the oil and gas sector.The insights garnered from these advanced modeling strategies are set to transform geological and engineering practices in hydrocarbon prediction,evaluation,and recovery. 展开更多
关键词 Regression analysis oil and gas exploration Multiple linear regression model Nonlinear regression model Hydrocarbon loss recovery Porosity prediction
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Review of Plant Essential Oils for Plant Pests Management
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作者 Fengmei YANG Yourong FU +6 位作者 Ranran NIE Bingkun CHEN Yuyun LIAO Qiwei ZHANG Cong CHEN Qianhua JI Yanjun GUO 《Plant Diseases and Pests》 2024年第4期25-32,共8页
This paper reviews the origins and classification of plant essential oil resources,along with prevalent extraction techniques for their active constituents.By integrating insights on the utilization of plant essential... This paper reviews the origins and classification of plant essential oil resources,along with prevalent extraction techniques for their active constituents.By integrating insights on the utilization of plant essential oils for plant pest management,the comprehensive analysis reveals multiple functionalities exhibited by plant essential oils,including fumigation,contact toxicity,repellent action,antifeedant activity,and growth inhibition.Furthermore,the paper highlights the challenges associated with plant essential oils in plant protection and outlines future research directions,aiming to offer valuable insights for the advancement of botanical insecticides. 展开更多
关键词 Plant essential oil INSECTICIDE Bioactivity Pest management Plant protection
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Protective effect of camellia oil on H_(2)O_(2)-induced oxidative stress injury in H9C2 cardiomyocytes of rats
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作者 YAN Qing GUO Zhen +3 位作者 SUN Sai-nan LI Jing TAN Ji-yong LI Jing 《Journal of Hainan Medical University》 CAS 2024年第1期1-7,共7页
Objective: To explore the protective effect of camellia oil against H2O2-induced oxidative stress injury in rat H9C2 cardiomyocytes. Methods: CCK8 method was used to detect the cell survival rate of H9C2 cardiomyocyte... Objective: To explore the protective effect of camellia oil against H2O2-induced oxidative stress injury in rat H9C2 cardiomyocytes. Methods: CCK8 method was used to detect the cell survival rate of H9C2 cardiomyocytes treated with different concentrations of H2O2. Normal cultured cells were used as the blank control group, and the cells were treated with 200 μmol/L H2O2 for 24 h. An oxidative stress injury model was constructed as the model group. The cells were pretreated with 1%, 0.1% and 0.01% camellia oil for 24 h, and then H2O2 was added for 24 h as the experimental group. The β-galactosidase senescence staining assay, mitochondrial membrane potential assay, EdU cell proliferation staining assay and scratch assay were used to observe the changes of cell senescence, mitochondrial membrane potential, proliferation, apoptosis and migration in each group. The superoxide dismutase (SOD) activity, lactate dehydrogenase (LDH) activity, and malondialdehyde (MDA) content of the cells in each group were detected by using the kit. Results: The cell viability of H9C2 cardiomyocytes treated with different concentrations of H2O2 was inhibited and positively correlated with the concentration of H2O2 (P<0.01). Compared with the blank control group, the positive rate of cell senescence, MDA content and LDH activity increased in the H2O2 model group (P<0.01);mitochondrial membrane potential, cellular value-added rate, migration rate and SOD activity decreased (P<0.01). Compared with the H2O2 model group, the positive rate of cellular senescence (P<0.01 or P<0.05), MDA content and LDH activity decreased (P< 0.01 or P<0.05);mitochondrial membrane potential increased, cell proliferation rate and migration rate increased (P<0.01 or P<0.05) in the experimental group. Conclusion: Camellia oil can significantly inhibit oxidative stress injury in H9C2 cells and exert cardiomyocyte protective effects. 展开更多
关键词 Camellia oil H_(2)O_(2) H9C2 Oxidative stress Protective
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Analysis of rotor eddy current loss and thermal deformation of magnetic liquid double suspension bearing
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作者 LIU Hongmei YANG Guang +3 位作者 SUN Yanan SUN Jian WANG Zhe ZHAO Jianhua 《High Technology Letters》 EI CAS 2024年第3期322-332,共11页
Magnetic-liquid double suspension bearing(MLDSB)is a new type of suspension bearing based on electromagnetic suspension and supplemented by hydrostatic supporting.Without affecting the electromagnetic suspension force... Magnetic-liquid double suspension bearing(MLDSB)is a new type of suspension bearing based on electromagnetic suspension and supplemented by hydrostatic supporting.Without affecting the electromagnetic suspension force,the hydrostatic supporting effect is increased,and the real-time coupling of magnetic and liquid supporting can be realized.However,due to the high rotation speed,the rotor part produces eddy current loss,resulting in a large temperature rise and large ther-mal deformation,which makes the oil film thickness deviate from the initial design.The support and bearing characteristics are seriously affected.Therefore,this paper intends to explore the internal effects of eddy current loss of the rotor on the temperature rise and thermal deformation of MLDSB.Firstly,the 2D magnetic flow coupling mathematical model of MLDSB is established,and the eddy current loss distribution characteristics of the rotor are numerically simulated by Maxwell software.Secondly,the internal influence of mapping relationship of structural operating parameters such as input current,coil turns and rotor speed on rotor eddy current loss is revealed,and the changing trend of rotor eddy current loss under different design parameters is explored.Thirdly,the eddy cur-rent loss is loaded into the heat transfer finite element calculation model as a heat source,and the temperature rise of the rotor and its thermal deformation are simulated and analyzed,and the influ-ence of eddy current loss on rotor temperature rise and thermal deformation is revealed.Finally,the pressure-flow curve and the distribution law of the internal flow field are tested by the particle image velocimetry(PIV)system.The results show that eddy current loss increases linearly with the in-crease of coil current,coil turns and rotor speed.The effect of rotational speed on eddy current loss is much higher than that of coil current and coil turns.The maximum temperature rise,minimum temperature rise and maximum thermal deformation of the rotor increase with the increase of eddy current loss.The test results of flow-pressure and internal trace curves are basically consistent with the theoretical simulation,which effectively verifies the correctness of the theoretical simulation.The research results can provide theoretical basis for the design and safe and stable operation of magnetic fluid double suspension bearings. 展开更多
关键词 magnetic-liquid double suspension bearing(MLDSB) oil film thickness cur-rent loss thermal deformation particle image velocimetry(PIV)test
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Application and Research of Meteorological Data in Lightning Protection Technical Service of Oil Depot
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作者 Liu Fengjiao He Qiuyan +2 位作者 Tang Yao Su Kai Liu Yueyu 《Meteorological and Environmental Research》 CAS 2019年第1期26-30,共5页
In this paper,lightning protection technical service of oil depot is taken as research object. It is proposed using various meteorological data to carry out multiple lightning protection technical services( risk asses... In this paper,lightning protection technical service of oil depot is taken as research object. It is proposed using various meteorological data to carry out multiple lightning protection technical services( risk assessment,potential forecast,monitoring and early warning of lightning disasters) based on conventional detection of lightning protection system,to improve technical content of lightning protection service and benefits of disaster prevention and mitigation. It mainly analyzes the application of lightning monitoring data in pre-assessment of lightning disaster,to guide site selection of new oil depot; guidance of lightning disaster status assessment on regular inspection of lightning protection system,to determine lightning protection detection time and update and maintenance time of lightning protection system; potential prediction and early warning of lightning,to guide daily operation of oil depot. 展开更多
关键词 METEOROLOGICAL DATA oil DEPOT LIGHTNING protection
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Coating Protection for Production Facilities of Offshore Oil Fields
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作者 Zhu, Chengde 《China Ocean Engineering》 SCIE EI 1993年第4期467-474,共8页
This paper describes coating protection of production facilities of offshore oil fields based on the practice of development of Bohai Offshore Oil Field, with focus laid on the selection of coating systems, surface pr... This paper describes coating protection of production facilities of offshore oil fields based on the practice of development of Bohai Offshore Oil Field, with focus laid on the selection of coating systems, surface preparation, coating application, as well as coating inspection for four types of major production facilities. 展开更多
关键词 Coating techniques CORROSION INSPECTION Ocean engineering offshore structures oil field equipment PAINT Protective coatings Surface treatment
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Application of Temporary Technology for Soil and Water Conservation in Crop Protection
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作者 Yu Sihang Yan Mengqing Zheng Xian 《Meteorological and Environmental Research》 CAS 2015年第4期18-20,共3页
The increasing of highway engineering construction makes soil and water loss surrounding highway and also influences the growth of crops around, To control soil and water loss, new engineering measures are put forward... The increasing of highway engineering construction makes soil and water loss surrounding highway and also influences the growth of crops around, To control soil and water loss, new engineering measures are put forward to protect soil and water and prevent crops from being damaged. 展开更多
关键词 Soil and water loss Temporary soil and water conservation Crop protection China
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Welcome Subscription '96 Environment Protection of Oil and Gas Fields
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《China Oil & Gas》 CAS 1995年第4期59-59,共1页
WelcomeSubscription'96EnvironmentProtectionofOilandGasFieldsEnvironmentProlectionofOilandGasHieldsisascienti... WelcomeSubscription'96EnvironmentProtectionofOilandGasFieldsEnvironmentProlectionofOilandGasHieldsisascientificandtechnicalpe... 展开更多
关键词 Environment protection of oil and Gas Fields Welcome Subscription
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Environmental Protection of Oil and Gas Fields 1997 Subscriptions Welcome
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《China Oil & Gas》 CAS 1996年第4期207-207,共1页
EnvironmentalProtectionofOilandGasFields1997SubscriptionsWelcomeENVIRONMENTALPROTECTIONOFLILANDGASFIELDS,isa... EnvironmentalProtectionofOilandGasFields1997SubscriptionsWelcomeENVIRONMENTALPROTECTIONOFLILANDGASFIELDS,isascientificandtech... 展开更多
关键词 Environmental protection of oil and Gas Fields 1997 Subscriptions Welcome
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Macular Perfusion Changes and Ganglion Cell Complex Loss in Patients with Silicone Oil-related Visual Loss 被引量:10
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作者 MA Ya ZHU Xiao Qing PENG Xiao Yan 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2020年第3期151-157,共7页
Objective The aim of this study was to investigate macular perfusion changes and ganglion cell complex(GCC)loss in patients with unexplained visual loss following vitrectomy and silicone oil(SO)tamponade,and to evalua... Objective The aim of this study was to investigate macular perfusion changes and ganglion cell complex(GCC)loss in patients with unexplained visual loss following vitrectomy and silicone oil(SO)tamponade,and to evaluate the correlation between retinal blood flow and GCC loss using optical coherence tomography angiography(OCTA)and optical coherence tomography(OCT).Methods This retrospective study included seven eyes(seven patients)with unexpected visual loss after vitrectomy and SO tamponade.OCTA was used to evaluate the alterations in retinal vessel density(VD)in the superficial capillary plexus(SCP),deep capillary plexus(DCP),and radial peripapillary capillary plexus(RPCP).OCT was used to measure the thickness of GCC and retinal nerve fiber layer(RNFL).Medical records of patients were reviewed.Results Quantitative analysis of OCTA images revealed a significant reduction in SCP VD in the affected eyes compared with the controls(all sections P<0.05).No difference was found in GCC thickness,but FLV(focal loss volume)and GLV(global loss volume)were significantly higher in the affected eyes(both P<0.001).SCP VD was inversely correlated with FLV and GLV.Conclusions Silicone oil-related severe visual loss was associated with superficial retinal microvasculature damage and ganglion cell apoptosis. 展开更多
关键词 SILICONE oil Visual loss Optical coherence tomography ANGIOGRAPHY GANGLION cell complex
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Numerical Simulation of Turbulent Flow of Hydraulic Oil through 90° Circular-sectional Bend 被引量:3
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作者 WANG Liwei GAO Dianrong ZHANG Yigong 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2012年第5期905-910,共6页
Oil flow through pipe bends is found in many engineering applications. However, up to now, the studies of oil flow field in the pipe bend appear to be relatively sparse, although the oil flow field and the associated ... Oil flow through pipe bends is found in many engineering applications. However, up to now, the studies of oil flow field in the pipe bend appear to be relatively sparse, although the oil flow field and the associated losses of pipe bend are very important in practice. In this paper, the relationships between the turbulent flow of hydraulic oil in a bend and the Reynolds number Re and the curvature ratio δare studied by using computational fluid dynamics (CFD). A particular emphasis is put on hydraulic oil, which differs from air or water, flowing through 90° circular-sectional bend, with the purpose of determining the turbulent flow characteristics as well as losses. Three turbulence models, namely, RNG κ-ε model, realizable k-ε model, and Reynolds stress model (RSM), are used respectively. The simulation results in the form of contour and vector plots for all the three turbulence models for pipe bends having curvature ratio of δ=0.5, and the detailed pressure fields and total pressure losses for different Re and δ for RSM are presented. The RSM can predict the stronger secondary flow in the bend better than other models. As Re increases, the pressure gradient changes rapidly, and the pressure magnitude increases at inner and outer wall of the bend. When δ decreases, two transition points or transition zones of pressure gradient arise at inner wall, meanwhile, the transition point moves towards the inlet at outer wall of the bend. Owing to secondary flow, the total pressure loss factor k increases as the bend tightens, on the contrary, as Re increases, factor k decreases due to higher velocity heads, and the rapid change of pressure gradient on the surface of the bend leads to increasing of friction and separation effects, and magnified swirl intensity of secondary flow. A new mathematical model is proposed for predicting pressure loss in terms of Re and δ in order to provide support to the one-dimensional simulation software. The proposed research provides reference for the analysis of oil flow with higher Re in the large bends. 展开更多
关键词 hydraulic oil 90° bend turbulent flow pressure loss computational fluid dynamics (CFD)
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Detection of oil spill based on CBF-CNN using HY-1C CZI multispectral images 被引量:3
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作者 Kai Du Yi Ma +2 位作者 Zongchen Jiang Xiaoqing Lu Junfang Yang 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2022年第7期166-179,共14页
Accurate detection of an oil spill is of great significance for rapid response to oil spill accidents.Multispectral images have the advantages of high spatial resolution,short revisit period,and wide imaging width,whi... Accurate detection of an oil spill is of great significance for rapid response to oil spill accidents.Multispectral images have the advantages of high spatial resolution,short revisit period,and wide imaging width,which is suitable for large-scale oil spill monitoring.However,in wide remote sensing images,the number of oil spill samples is generally far less than that of seawater samples.Moreover,the sea surface state tends to be heterogeneous over a large area,which makes the identification of oil spills more difficult because of various sea conditions and sunglint.To address this problem,we used the F-Score as a measure of the distance between forecast value and true value,proposed the Class-Balanced F loss function(CBF loss function)that comprehensively considers the precision and recall,and rebalances the loss according to the actual sample numbers of various classes.Using the CBF loss function,we constructed convolution neural networks(CBF-CNN)for oil spill detection.Based on the image acquired by the Coastal Zone Imager(CZI)of the Haiyang-1C(HY-1C)satellite in the Andaman Sea(study area 1),we carried out parameter adjustment experiments.In contrast to experiments of different loss functions,the F1-Score of the detection result of oil emulsions is 0.87,which is 0.03–0.07 higher than cross-entropy,hinge,and focal loss functions,and the F1-Score of the detection result of oil slicks is 0.94,which is 0.01–0.09 higher than those three loss functions.In comparison with the experiment of different methods,the F1-Score of CBF-CNN for the detection result of oil emulsions is 0.05–0.12 higher than that of the deep neural networks,supports vector machine and random forests models,and the F1-Score of the detection result of oil slicks is 0.15–0.22 higher than that of the three methods.To verify the applicability of the CBF-CNN model in different observation scenes,we used the image obtained by HY-1C CZI in the Karimata Strait to carry out experiments,which include two studies areas(study area 2 and study area 3).The experimental results show that the F1-Score of CBF-CNN for the detection result of oil emulsions is 0.88,which is 0.16–0.24 higher than that of other methods,and the F1-Score of the detection result of oil slicks is 0.96–0.97,which is 0.06–0.23 higher than that of other methods.Based on all the above experiments,we come to the conclusions that the CBF loss function can restrain the influence of oil spill and seawater sample imbalance on oil spill detection of CNN model thus improving the detection accuracy of oil spills,and our CBF-CNN model is suitable for the detection of oil spills in an area with weak sunglint and can be applied to different scenarios of CZI images. 展开更多
关键词 oil spills CNN CLASSIFICATION loss function sunglint DETECTION
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Oil source and migration process in oblique transfer zone of Fushan Sag,northern South China Sea 被引量:1
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作者 王观宏 王华 +3 位作者 甘华军 时阳 赵迎冬 陈善斌 《Journal of Central South University》 SCIE EI CAS CSCD 2016年第3期654-668,共15页
The oblique transfer zone in the Fushan Sag, a syndepositional dome sandwiched between the Bailian and Huangtong sub-sags, has been the most important exploration target. The major oil observation occurs in the E_2l_1... The oblique transfer zone in the Fushan Sag, a syndepositional dome sandwiched between the Bailian and Huangtong sub-sags, has been the most important exploration target. The major oil observation occurs in the E_2l_1^(L+M) and the E_2l_3~U. 46 oil and rock samples reveal that the oil in the transfer zone is mostly contributed by the Bailian sub-sag, though the source rock conditions, hydrocarbon generation and expulsion histories of the Bailian and Huangtong sub-sags are similar. The E_2l_3~U oil, characterized by high maturity, Pr/Ph ratio and oleanane/C_(30)-hopane ratio, shows a close genetic affinity with the E_2l_3~b source rocks, while the E_2l_1^(L+M) oil, characterized by lower maturity, Pr/Ph ratio and oleanane/C_(30)-hopane ratio, is suggested to be derived from the E_2l_(1+2)~b source rocks. The homogenization temperatures of aqueous fluid inclusions, taking the burial history of the reservoirs into account, reflect that the oil charge mainly occurred from mid-Miocene to Pliocene in the oblique transfer zone. The oil transporting passages include connected sand bodies, unconformities and faults in the Fushan Sag. Of these, the faults are the most complicated and significant. The faults differ sharply in the west area, the east area and the oblique transfer zone, resulting in different influence on the oil migration and accumulation. During the main hydrocarbon charge stage, the faults in the west area are characterized by bad vertical sealing and spatially dense distribution. As a result, the oil generated by the Huangtong source rocks is mostly lost along the faults during the vertical migration in the west area. This can be the mechanism proposed to explain the little contribution of the Huangtong source rocks to the oil in the oblique transfer zone. Eventually, an oil migration and accumulation model is built in the oblique transfer zone, which may provide theoretical and practical guides for the oil exploration. 展开更多
关键词 oblique transfer zone oil-source correlation oil loss oil migration and accumulation model Fushan Sag
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Development of key additives for organoclay-free oil-based drilling mud and system performance evaluation 被引量:1
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作者 SUN Jinsheng HUANG Xianbin +3 位作者 JIANG Guancheng LYU Kaihe LIU Jingping DAI Zhiwen 《Petroleum Exploration and Development》 2018年第4期764-769,共6页
Traditional oil-based drilling muds(OBMs) have a relatively high solid content, which is detrimental to penetration rate increase and reservoir protection. Aimed at solving this problem, an organoclay-free OBM system ... Traditional oil-based drilling muds(OBMs) have a relatively high solid content, which is detrimental to penetration rate increase and reservoir protection. Aimed at solving this problem, an organoclay-free OBM system was studied, the synthesis methods and functioning mechanism of key additives were introduced, and performance evaluation of the system was performed. The rheology modifier was prepared by reacting a dimer fatty acid with diethanolamine, the primary emulsifier was made by oxidation and addition reaction of fatty acids, the secondary emulsifier was made by amidation of a fatty acid, and finally the fluid loss additive of water-soluble acrylic resin was synthesized by introducing acrylic acid into styrene/butyl acrylate polymerization. The rheology modifier could enhance the attraction between droplets, particles in the emulsion via intermolecular hydrogen bonding and improve the shear stress by forming a three-dimensional network structure in the emulsion. Lab experimental results show that the organoclay-free OBM could tolerate temperatures up to 220 ?C and HTHP filtration is less than 5 m L. Compared with the traditional OBMs, the organoclay-free OBM has low plastic viscosity, high shear stress, high ratio of dynamic shear force to plastic viscosity and high permeability recovery, which are beneficial to penetration rate increase, hole cleaning and reservoir protection. 展开更多
关键词 organoclay-free oil-BASED drilling MUD rheology MODIFIER EMULSIFIER fluid loss REDUCER weak gel reservoir protection
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Space Charge Characteristics of Oil-paper Insulation with New Paper and Aged Oil 被引量:1
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作者 MU Haibao WANG Da +4 位作者 WANG Shiqiang TIAN Jie LI Yuan WEI Yanhui ZHANG Guanjun 《高电压技术》 EI CAS CSCD 北大核心 2013年第8期1865-1872,共8页
Oil-paper compound insulation has been widely used in power transformers for quite a long time because of its good performances. The insulation gradually degrades under combined thermal, electrical and chemical stress... Oil-paper compound insulation has been widely used in power transformers for quite a long time because of its good performances. The insulation gradually degrades under combined thermal, electrical and chemical stresses during routine operations, mainly because of space charges inside. This work investigated the space charge characteristics in oil-paper insulation under oil aging circumstance. New trans- former oil samples are thermally aged to obtain different aging states, and their physical and chemical properties are analyzed. New Kraft papers are dried in vacuum and fully immersed in these different aged oil samples, and three kinds of oil-paper samples are obtained. We use the pulsed electro-acoustic (PEA) method to measure space charge under both DC voltage-on and voltage-off conditions at room temperature. The effect of oil aging state on characteristics of space charge injection, accumulation, and decay is analyzed and discussed. The results show that comparing with the DC voltage-off condition, more charges are injected into samples at the interface of electrode and dielectric when DC voltage is on. When the oil-aged state gets worse, more charges are induced at both cathode and anode, more space charges are accumulated in the bulk, the area of negative charges is larger, and local electric field is distorted more seriously. Moreover, for the voltage-off condition, aged oil is good for space charge decay, and trapped positive space charges decay faster than trapped negative charges. 展开更多
关键词 空间电荷 油纸绝缘 电荷特性 老年 老化状态 直流电压 衰减特性 电荷积累
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RESEARCHES ON RELATIONSHIP BETWEEN HEARING LOSS AND CONTENT OF Fe AND Zn IN PERILYMPH,CSF,SERUM,AND HAIRS
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作者 许珉 樊玉林 +2 位作者 高振宗 李建中 陈洁 《Journal of Pharmaceutical Analysis》 CAS 1995年第1期78-82,86,共6页
Fe and Zn levels in perilymph in guinea pigs injected with gentamicin(GM)were examined in this experlment,and those leves were compared with their correspondents in CSF,serum andhairs.Preventive and therapeutic action... Fe and Zn levels in perilymph in guinea pigs injected with gentamicin(GM)were examined in this experlment,and those leves were compared with their correspondents in CSF,serum andhairs.Preventive and therapeutic actions of seabuckthorn oil and injective gastrodini to hearing losswe observed.The results showed:①Fe content in perilymph and hair in GM ototxic guinea Pigswas increased,and was decreased after prevention and treating. There was no obvious change in CSFand serum.②Zn content in perilymph was increased in GM ototoxic guinea pigs,and was furtherincreased after prevention.Zn contents in serum and hairs were significantly decreased.The resultssuggest that GM ototoxic reaction is related to increasing Fe contents,and elevation ot Zn content isrelated to the compensative reaction of the body.The cjamges of chemical elements in perilymph aremore important than those in CSF,serum and hairs for pathologic changes in the cochlea,seabuckthorn oil can prevent GM ototoxic reaction. 展开更多
关键词 PERILYMPH Fe content Zn content GENTAMICIN hearing loss seabuckthorn oil
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Information system for emergence decision on the protection against earthquake and disaster reduction in Shanghai City──Application of GIS
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作者 宋俊高 朱元清 +2 位作者 火恩杰 严大华 杨挺 《Acta Seismologica Sinica(English Edition)》 CSCD 2000年第4期454-465,共12页
For meeting the need of rapid development of economy in Shanghai and the protection against earthquake and disaster reduction in the mega city, it is necessary to build a information system for emergence decision on t... For meeting the need of rapid development of economy in Shanghai and the protection against earthquake and disaster reduction in the mega city, it is necessary to build a information system for emergence decision on the protection against earthquake and disaster reduction in the city. In this paper, GIS is applied to 'the information system for emergence decision on the protection against earthquake and disaster reduction in Shanghai City (Baoshan experiment region)'. We introduce to the structure and effect of each functional module in this information system. This information system consists of 7 functional modules:background information of seismology and geology, subsystem for rapid evaluation of damage loss from earthquake, subsystem for the decisive information on earthquake emergence, information query, maintenance and management of system, help, quit. The key parts of this information system are the subsystem for rapid evaluation of damage loss from earthquake and the subsystem for the decisive information on earthquake emergence. Also, this paper introduces to the application of technology of color infra-red aerial photograph remote sensing to this information system. 展开更多
关键词 Geographical Information System (GIS) protection against earthquake and disaster reduction evaluation of earthquake damage loss emergence decision
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Numerical Simulation on Oil Spilling of Submarine Pipeline and Its Evolution on Sea Surface
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作者 Yi Wang Mohan Lin 《Computer Modeling in Engineering & Sciences》 SCIE EI 2020年第9期885-914,共30页
Due to the interaction and corrosion of the seawater,submarine pipelines are easy to be broken to spill oil.The special environment of subsea restricts the technical development of pipeline maintenance.Therefore,the s... Due to the interaction and corrosion of the seawater,submarine pipelines are easy to be broken to spill oil.The special environment of subsea restricts the technical development of pipeline maintenance.Therefore,the study on the oil spilling model of submarine pipeline is very important for predicting the movement and diffusion of spilled oil,so that oil spilling traces and relating strategies can be determined.This paper aims to establish an oil spilling model of a submarine pipeline,study the movement characteristics of spilled oil in seawater by numerical simulation,and determine the traces,diffusion range,time to sea surface,etc.Then,the maximum horizontal migration distance(MHMD)with corresponding time are analyzed under different oil densities,spilling speeds and seawater velocities.Results show that the MHMD decreases first and then increases while the time to achieve the MHMD increases along with increasing oil density.The MHMD increases while the time to achieve the MHMD decreases,along with increasing spilling speed.Both the MHMD and corresponding time increase along with increasing seawater velocity.Based on numerical results,a correlation of spilling distance and spilling time is proposed to give fast and accurate predictions.After the oil reaches sea surface,oil expansion and transport are simulated.Euler-Lagrange method is used in the simulation.Dynamic and non-dynamic factors are considered.Results show that wind velocity and water velocity are dominant in dynamic factors.When they are large,spilled oil moves very fast with variable directions in complex flow field.Nondynamic factors such as evaporation,emulsion and solution mainly reduce the volume of oil film.They almost do not affect the direction and displacement of spilled oil.Quick response should be made for large wind and water velocities when the placement of oil boom is given.With the correlation and simulation,emergency responses can be guided effectively to reduce the impact of submarine oil pollution.The computational results benefit pollution control and environmental protection in marine petroleum engineering. 展开更多
关键词 Computational fluid dynamics submarine pipeline oil spilling pollution control environmental protection
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Assessing the Impact of Storage Temperature on the Stability and Biocidal Activity of Essential oils Formulated, Case Tribolium Castaneum (herbst). (insecta, tenebrionidae)
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作者 Ouchai Malika Moussaoui Kamel Djazoulli Zahredine 《Journal of Environmental Science and Engineering(A)》 2016年第8期406-415,共10页
In this paper, authors describe how to carry out a research assessing the impact of storage temperature on the stability and biocidal activity of formulated essential oils. Cereals, like other stored food, currently e... In this paper, authors describe how to carry out a research assessing the impact of storage temperature on the stability and biocidal activity of formulated essential oils. Cereals, like other stored food, currently experience serious health problems of storage. The offending agents are primary pests such as Sitophilusoryzae and secondary pests including Tribolium. This study focused on the evaluation of the biocidal effect on the essential oils of thyme and citrus, against red flour beetle adults (Triboliumcastaneum) under different temperature regimes. The results showed that different molecules produced a delayed effect (12 h-14 h-16 h-I 8 h) on the populations of Triboliumcastaneum at the storage temperature of 20 ~C. The same results showed an early striking effect of thymol and carvacrol on Triboliumcastaneum compared to limonene. The toxicity of thymol and carvacrol was much more active than limonene at 12 h, which was very remarkable as limonene expressed its toxicity from 14 h with a deadly effect. When temperatures are under 20 ℃ and 25℃, thymol showed a greater degree of efficiency followed by carvacrol and limonene which had lower efficiency. However, at 28℃, carvacrol expressed a very significant biocidal effect compared to the other two formulations, thymol and limonene. 展开更多
关键词 Thymusfontanesii bio-efficacy essential oils bioactive molecules Triboliumcastaneum plant protection.
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Measures of Environmental Protection of Petroleum Exploration and Development in Tarim Basin
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作者 Xia Jianjiang(Environment Protecting Section, Engineering Management Department,Tarim Petroleum Exploration and Development)Zhao Guihai(Xinjiang Institute of Biology, Pedology and Desert Research, Chinese Academy of Sciences) 《China Oil & Gas》 CAS 1996年第4期251-252,共2页
MeasuresofEnvironmentalProtectionofPetroleumExplorationandDevelopmentinTarimBasinXiaJianjiang(EnvironmentPro... MeasuresofEnvironmentalProtectionofPetroleumExplorationandDevelopmentinTarimBasinXiaJianjiang(EnvironmentProtectingSection,En... 展开更多
关键词 Enviromental protection oil and gas EXPLORATION DEVELOPMENT DESERT
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