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Experimental evaluation of reformate-assisted diesel NOx trap desulfation 重整燃料辅助柴油NOx捕集器脱硫试验评价
SAE transactions Pub Date : 2005-10-24 DOI: 10.4271/2005-01-3878
Wu Ming-Cheng, T. Han, G. Fisher
{"title":"Experimental evaluation of reformate-assisted diesel NOx trap desulfation","authors":"Wu Ming-Cheng, T. Han, G. Fisher","doi":"10.4271/2005-01-3878","DOIUrl":"https://doi.org/10.4271/2005-01-3878","url":null,"abstract":"NO, adsorber catalysts are leading candidates for improving NO, aftertreatment in diesel exhaust. The major challenge in the use of adsorbers that capture NO, in the form of nitrates is their susceptibility to sulfur poisoning. Sulfur, which is present in diesel fuel, adsorbs and accumulates as sulfate (SO -2 4 ) at the same adsorption sites as NO,, and, since it is more stable than nitrates, inhibits the ability of the catalyst to adsorb NO,. It is found that high temperature (> about 650 °C) in the presence of a reducing gas is required to release sulfur rapidly from the catalyst. Since the peak temperatures of diesel engine exhaust are below 400 °C, additional heat is required to remove the sulfur. This work describes a reformate-assisted \"sulfur purge\" method, which employs heat generated inside the NO, trap catalyst by exothermic chemical reactions between the oxygen in diesel exhaust and injected reformate (H 2 + CO). Our results with a laboratory gas bench system show that catalyst desulfation is successful following a desulfation schedule with an inlet gas temperature of about 300 °C. In addition, we have examined impact of temperature, duration of exposure, and reformate-based gas compositions employed for rich-gas desulfation on NO, adsorber efficiency.","PeriodicalId":21404,"journal":{"name":"SAE transactions","volume":"415 1","pages":"1766-1773"},"PeriodicalIF":0.0,"publicationDate":"2005-10-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87112819","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 8
A Piezoelectric Sensor Concept for Measuring Piston Wetting in DISI Engines 基于压电传感器的活塞湿润度测量
SAE transactions Pub Date : 2005-10-24 DOI: 10.4271/2005-01-3873
A. Camacho, M. Hall
{"title":"A Piezoelectric Sensor Concept for Measuring Piston Wetting in DISI Engines","authors":"A. Camacho, M. Hall","doi":"10.4271/2005-01-3873","DOIUrl":"https://doi.org/10.4271/2005-01-3873","url":null,"abstract":"A piezoelectric sensor to measure the mass of fuel that impacts the piston top during injection in a direct injection spark ignition (DISI) engine was developed. The sensor used a 3.18 cm (1.25-inch) long, 0.318 cm (0.125-inch) wide piezo bending motor. The principle of operation is based on the change in natural vibration frequency that occurs to the cantilever piezo beam due to a change in its mass caused by the presence of liquid fuel on its surface. An electrical impulse is used to set the piezo element in vibration after which the natural vibrational frequency is measured using a FFT analyzer. The concept was evaluated outside the engine and calibrated for the frequency shift as a function of the weight of liquid on the bending element. The change in the frequency was found to be approximately proportional to the liquid mass on the sensor. The piston top of the engine was modified to accommodate the sensor on its surface. Due to temperature limitations, all fuel film mass measurements were taken under motored conditions. A wide range of equivalence ratios and injection timings were considered in the experiments. The measurements showed that the fuel film mass deposited on the sensor surface was small, typically less than 2 mg, which corresponds to a film height of 32 μm. The fuel film mass followed a general trend increasing in value and reaching a maximum for injection timings when the piston surface approached TDC. The maximum measured mass for stoichiometric operation was 2.3 mg at TDC and corresponds to 6.3% of the fuel injected. The average evaporation rate of the fuel film mass was 3.3 kg/m 2 -s, and was nearly the same for all injection timings. The average measurement uncertainty was calculated as ±0.56 mg for stoichiometric operation.","PeriodicalId":21404,"journal":{"name":"SAE transactions","volume":"96 1","pages":"1756-1769"},"PeriodicalIF":0.0,"publicationDate":"2005-10-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"91141301","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 3
Impact of Vehicle Weight on Truck Behavior and Emissions, using On-Board Measurement 车辆重量对卡车行为和排放的影响,使用车载测量
SAE transactions Pub Date : 2005-10-24 DOI: 10.4271/2005-01-3788
Corey M. Strimer, N. Clark, D. Carder, M. Gautam, G. Thompson
{"title":"Impact of Vehicle Weight on Truck Behavior and Emissions, using On-Board Measurement","authors":"Corey M. Strimer, N. Clark, D. Carder, M. Gautam, G. Thompson","doi":"10.4271/2005-01-3788","DOIUrl":"https://doi.org/10.4271/2005-01-3788","url":null,"abstract":"On-board emissions measurement for heavy-duty vehicles has taken on greater significance because new standards now address in-use emissions levels in the USA. Emissions compliance must be shown in a \"Motto-exceed\" (NTE) zone that excludes engine operation at low power. An over-the-road 1996 Peterbilt tractor was instrumented with the West Virginia University Mobile Emissions Measurement System (MEMS). The researchers determined how often the truck entered the NTE, and the emissions from the vehicle, as it was driven over different routes and at different test weights (20,740 Ib, 34,640 Ib, 61,520 Ib, and 79,700 lb) The MEMS interfaced with the truck ECU, while also measuring exhaust flowrate, and concentrations of carbon dioxide (CO 2 ) and oxides of nitrogen (NOx) in the exhaust. The four test routes that were employed included varying terrain types in order to simulate a wide range of on-road driving conditions. One route (called the Bruceton route) included a sustained hill climb. Another route (known as the Saltwell route) traversed more rolling hills throughout the duration of the test. For 34,640 lb and 79,700 lb, the vehicle was tested on a route that was a reasonably flat road (PA 43 route), and a route through city traffic (Stop-n-go). As an example of results from the study, on the Bruceton route at 20,740 lb, the truck spent only 8.24% of the time within the NTE, but at 80,000lb on the same route it spent 35.67% of test duration in the NTE. Distance-specific NOx and fuel consumption were typically 50 to 80% higher in the NTE zone than over the whole route.","PeriodicalId":21404,"journal":{"name":"SAE transactions","volume":"1 1","pages":"1630-1641"},"PeriodicalIF":0.0,"publicationDate":"2005-10-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89671292","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 5
Enthalpy-based flamelet model for HCCI applied to a rapid compression machine 基于焓的HCCI火焰模型应用于快速压缩机
SAE transactions Pub Date : 2005-10-24 DOI: 10.4271/2005-01-3735
D. Cook, H. Pitsch
{"title":"Enthalpy-based flamelet model for HCCI applied to a rapid compression machine","authors":"D. Cook, H. Pitsch","doi":"10.4271/2005-01-3735","DOIUrl":"https://doi.org/10.4271/2005-01-3735","url":null,"abstract":"Homogeneous-Charge Compression Ignition (HCCI) engines have been shown to have higher thermal efficiencies and lower NO x and soot emissions than Spark Ignition engines. However, HCCI engines experience high levels of carbon monoxide (CO) and unburnt hydrocarbon (UHC) emissions. These pollutants are formed in regions of the cylinder where wall heat loss is significant. Improving CO and UHC emissions in HCCI engines requires a fundamental understanding of the heat loss, chemical kinetics, and transport between near wall regions and regions less affected by heat loss. In this study an enthalpy-based flamelet approach is introduced and applied in a simulation of a Rapid Compression Machine operated under HCCI conditions. This approach directly models transport between regions of higher and lower enthalpies. Results are compared to experimental data from Murase and Hanada [6]. The simulations correctly predict ignition timing trends as a function of initial mixture temperature. Additionally, the affect of modeled transport across enthalpies on ignition characteristics is quantified. It is demonstrated that this term is important and is of comparable magnitude to the chemical source term.","PeriodicalId":21404,"journal":{"name":"SAE transactions","volume":"61 1","pages":"1558-1565"},"PeriodicalIF":0.0,"publicationDate":"2005-10-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"83886230","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 10
Dynamometer testing of an ethanol-water fueled transit van 一辆以乙醇水为燃料的运输货车的测功机测试
SAE transactions Pub Date : 2005-10-24 DOI: 10.4271/2005-01-3706
Jeremy Olberding, Dan Cordon Steven Beyerlein, J. Steciak, Mark Cherry
{"title":"Dynamometer testing of an ethanol-water fueled transit van","authors":"Jeremy Olberding, Dan Cordon Steven Beyerlein, J. Steciak, Mark Cherry","doi":"10.4271/2005-01-3706","DOIUrl":"https://doi.org/10.4271/2005-01-3706","url":null,"abstract":"Previous research using catalytic igniters and ethanol water fueled mixtures has shown potential for lowering CO and NO x emissions while increasing engine efficiency over conventional -engine configurations. Catalytic ignition systems allow combustion initiation over a much wider range of stoichiometry and water composition than traditional spark ignition systems. The platform explored in this research is a transit van converted to operate on either gasoline or ethanol water fuel mixtures. Special attention was devoted to improve cold starting and installing additional on board sensors and equipment for future testing. System features include integration of a wide band oxygen sensor, state-of-the-art engine management system, exhaust gas temperature sampling using platinum thin film resistive temperature devices and variable voltage control of catalytic igniters using DC-DC boost converters. The platform explored in this research is a transit van converted to operate on either gasoline or ethanol water fuel mixtures. Special attention was devoted to improve cold starting and installing additional on board sensors and equipment for future testing. System features include integration of a wide band oxygen sensor, state-of-the-art engine management system, exhaust gas temperature sampling using platinum thin film resistive temperature devices, and variable voltage control of catalytic igniters using DC-DC boost converters. Extensive engine performance and emissions testing for 70% ethanol 30% water fuel mixtures operating at air to fuel ratios (AFR) of = 1 and = 1.15 have shown a substantial reduction in NOx and CO emissions without the use of exhaust after treatment compared to gasoline emissions. Lean mixtures also show reduced emissions and increased thermal efficiency compared to stoichiometric conditions. Chassis dynamometer tests comparing thermal efficiency, and brake specific emissions of NOx, CO 2 , CO, and hydrocarbons for the ethanol-water fuel mixtures over a wide range of operating conditions are shown.","PeriodicalId":21404,"journal":{"name":"SAE transactions","volume":"8 1","pages":"1253-1264"},"PeriodicalIF":0.0,"publicationDate":"2005-10-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88425971","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 30
A history of mack engine lubricant tests from 1985-2005 : Mack T-7 through mack T-12 1985-2005年mack发动机润滑油测试历史:mack T-7至mack T-12
SAE transactions Pub Date : 2005-10-24 DOI: 10.4271/2005-01-3713
G. Shank, Kent Goshorn, M. W. Cooper, W. V. Dam, S. Richards
{"title":"A history of mack engine lubricant tests from 1985-2005 : Mack T-7 through mack T-12","authors":"G. Shank, Kent Goshorn, M. W. Cooper, W. V. Dam, S. Richards","doi":"10.4271/2005-01-3713","DOIUrl":"https://doi.org/10.4271/2005-01-3713","url":null,"abstract":"As on-highway, heavy-duty diesel engine designs have evolved to meet tighter emissions specifications and greater customer requirements, the crankcase environment for heavy-duty engine lubricants has changed. Engine lubricant quality is very important to help ensure engine durability, engine performance, and reduce maintenance downtime. Beginning in the late 1980's, a new Mack genuine oil specification and a new American Petroleum Institute (API) heavy-duty engine lubricant category have been introduced with each new U.S. heavy-duty, on-highway emissions specification. This paper documents the history and development of the Mack T-7, T-8, T-8A, T-8E, T-9, T-10, T-11, and T-12 engine lubricant tests.","PeriodicalId":21404,"journal":{"name":"SAE transactions","volume":"56 1","pages":"1289-1307"},"PeriodicalIF":0.0,"publicationDate":"2005-10-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75971477","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 9
Oxidation and Antiwear Retention Capability of Low-Phosphorus Engine oils 低磷发动机油的氧化和抗磨保持能力
SAE transactions Pub Date : 2005-10-24 DOI: 10.4271/2005-01-3822
Hong-liang Gao, K. Bjornen, A. Gangopadhyay, R. Jensen
{"title":"Oxidation and Antiwear Retention Capability of Low-Phosphorus Engine oils","authors":"Hong-liang Gao, K. Bjornen, A. Gangopadhyay, R. Jensen","doi":"10.4271/2005-01-3822","DOIUrl":"https://doi.org/10.4271/2005-01-3822","url":null,"abstract":"Future vehicle emission regulations both in the US and Europe will require maintaining catalyst efficiency for longer mileage intervals. In order to achieve this requirement, chemical restrictions are being placed on elements in engine oil that can poison catalysts. Most of phosphorus and a significant amount of sulfur in current engine oils come from zinc dialkyldithiophosphates, ZDDPs, which are a class of cost-effective multifunctional additives providing wear, oxidation and corrosion protection. Reducing ZDDP concentrations raises oxidation and wear concerns. The overall purpose of this research is to look at the antioxidation and antiwear capability of low phosphorus engine oils containing 0.05 wt% phosphorus and the potential of engine oils formulated without phosphorus. In addition to fresh oils, used oils drained from fleet vehicles were also analyzed and evaluated. The results indicate that by appropriately selecting and balancing supplemental phosphorus-free antioxidation and antiwear additives the antioxidation capability can be improved for low phosphorus and even non-phosphorus oils, and the antiwear performance of low phosphorus oils could be maintained or even improved.","PeriodicalId":21404,"journal":{"name":"SAE transactions","volume":"85 3 1","pages":"1544-1550"},"PeriodicalIF":0.0,"publicationDate":"2005-10-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"76193748","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 12
A Hybrid 2-Zone/WAVE Engine Combustion Model for Simulating Combustion Instabilities During Dilute Operation 一种用于模拟稀工况燃烧不稳定性的混合型2区/波发动机燃烧模型
SAE transactions Pub Date : 2005-10-24 DOI: 10.4271/2005-01-3801
K. Edwards, R. M. Wagner, V. Chakravarthy, C. Daw, Johney B. Green
{"title":"A Hybrid 2-Zone/WAVE Engine Combustion Model for Simulating Combustion Instabilities During Dilute Operation","authors":"K. Edwards, R. M. Wagner, V. Chakravarthy, C. Daw, Johney B. Green","doi":"10.4271/2005-01-3801","DOIUrl":"https://doi.org/10.4271/2005-01-3801","url":null,"abstract":"Internal combustion engines are operated under conditions of high exhaust gas recirculation (EGR) to reduce NO x emissions and promote enhanced combustion modes such as HCCI. However, high EGR under certain conditions also promotes nonlinear feedback between cycles, leading to the development of combustion instabilities and cyclic variability. We employ a two-zone phenomenological combustion model to simulate the onset of combustion instabilities under highly dilute conditions and to illustrate the impact of these instabilities on emissions and fuel efficiency. The two-zone in-cylinder combustion model is coupled to a WAVE engine-simulation code through a Simulink interface, allowing rapid simulation of several hundred successive engine cycles with many external engine parametric effects included. We demonstrate how this hybrid model can be used to study strategies for adaptive feedback control to reduce cyclic combustion instabilities and, thus, preserve fuel efficiency and reduce emissions.","PeriodicalId":21404,"journal":{"name":"SAE transactions","volume":"36 1","pages":"1642-1649"},"PeriodicalIF":0.0,"publicationDate":"2005-10-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"74502432","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 8
On The Road to 2010 Emissions: Field Test Results and Analysis with DPF-SCR System and Ultra Low Sulfur Diesel Fuel 在通往2010年排放的道路上:DPF-SCR系统和超低硫柴油的现场测试结果和分析
SAE transactions Pub Date : 2005-10-24 DOI: 10.4271/2005-01-3716
J. Mcgeehan, S. Yeh, M. Couch, Andreas Hinz, B. Otterholm, A. P. Walker, P. Blakeman
{"title":"On The Road to 2010 Emissions: Field Test Results and Analysis with DPF-SCR System and Ultra Low Sulfur Diesel Fuel","authors":"J. Mcgeehan, S. Yeh, M. Couch, Andreas Hinz, B. Otterholm, A. P. Walker, P. Blakeman","doi":"10.4271/2005-01-3716","DOIUrl":"https://doi.org/10.4271/2005-01-3716","url":null,"abstract":"This paper reviews field test results in 23 Volvo D12C non-Exhaust Gas Recirculation (EGR) diesel engines using continuously regenerating Diesel Particulate Filter (DPF) with Selective Catalytic Reduction (SCR) and ultra low sulfur diesel fuel at 4-10 ppm. This 2-year field test provided an opportunity to measure on-road nitrogen oxide (NO x ) emissions, and to do in-depth analysis of the incombustible material remaining in the filters. In addition, two crankcase oils were used at 1.0% and 1.4% sulfated ash to provide enhanced information on the material collected in the filters, and on oil drain capability. The study demonstrates that the U.S. Environmental Protection Agency (EPA) 2007 emissions can be met. After 2 years in the field the 23 trucks using the DPF-SCR system are still providing a very high NO x conversion of 75% on fleet average. The filter material contained only 2 wt-% carbon, which demonstrates the effectiveness of the DPF-SCR system in combusting soot. The material in the filters is dominated by combustion products of lubricant additives. The particle size distribution is bimodal, with a large number of particles of 0.4 micron diameter and the remaining at 8 microns. Overwhelmingly, the majority of particles are submicron. There was no difference in the filter material from the two lubricants evaluated, but they did vary in their estimated oil drain capability. This paper also reviews maintenance practices in this successful 2-year \"clean diesel\" program.","PeriodicalId":21404,"journal":{"name":"SAE transactions","volume":"29 1","pages":"1308-1322"},"PeriodicalIF":0.0,"publicationDate":"2005-10-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82740378","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 52
Cam-Phasing Optimization Using Artificial Neural Networks as Surrogate Models-Maximizing Torque Output 利用人工神经网络作为替代模型的凸轮相位优化-最大扭矩输出
SAE transactions Pub Date : 2005-10-24 DOI: 10.4271/2005-01-3757
Bin Wu, R. Prucka, Z. Filipi, D. Kramer, G. Ohl
{"title":"Cam-Phasing Optimization Using Artificial Neural Networks as Surrogate Models-Maximizing Torque Output","authors":"Bin Wu, R. Prucka, Z. Filipi, D. Kramer, G. Ohl","doi":"10.4271/2005-01-3757","DOIUrl":"https://doi.org/10.4271/2005-01-3757","url":null,"abstract":"Variable Valve Actuation (WA) technology provides high potential in achieving high performance, low fuel consumption and pollutant reduction. However, more degrees of freedom impose a big challenge for engine characterization and calibration. In this study, a simulation based approach and optimization framework is proposed to optimize the setpoints of multiple independent control variables. Since solving an optimization problem typically requires hundreds of function evaluations, a direct use of the high-fidelity simulation tool leads to the unbearably long computational time. Hence, the Artificial Neural Networks (ANN) are trained with high-fidelity simulation results and used as surrogate models, representing engine's response to different control variable combinations with greatly reduced computational time. To demonstrate the proposed methodology, the cam-phasing strategy at Wide Open Throttle (WOT) is optimized for a dual-independent Variable Valve Timing (WT) engine. The optimality of the cam-phasing strategy is validated with engine dynamometer tests.","PeriodicalId":21404,"journal":{"name":"SAE transactions","volume":"36 1","pages":"1586-1599"},"PeriodicalIF":0.0,"publicationDate":"2005-10-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"77307615","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 40
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