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Fuzzy Synthetic Evaluation of Water Quality of Naoli River Using Parameter Correlation Analysis 被引量:14
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作者 WANG Jianhua LU Xianguo +1 位作者 TIAN Jinghan JIANG Ming 《Chinese Geographical Science》 SCIE CSCD 2008年第4期361-368,共8页
In order to improve the effectiveness of Fuzzy Synthetic Evaluation (FSE) models, a Parameter Correlation Analysis (PCA) was introduced into the FSE and a case study was carried out in the Naoli River in the Sanjiang ... In order to improve the effectiveness of Fuzzy Synthetic Evaluation (FSE) models, a Parameter Correlation Analysis (PCA) was introduced into the FSE and a case study was carried out in the Naoli River in the Sanjiang Plain, Northeast China. The basic principle of the PCA is that the pairs of parameters which are highly correlated and linear with each other would contribute the same information to an assessment and one of them should be eliminated. The method of the PCA is that a correlation relationship among candidate parameters is examined before the FSE. If there is an apparent nonlinear or curvilinear relationship between two parameters, then both will be retained; if the correlation is significant (p<0.01), and the scatter plot suggests a linear relationship, then one of them will be deleted. However, which one will be deleted? For solving this problem, a sensitivity test was conducted and the higher sensitivity parameters remained. The results indicate that the original data should be preprocessed through the PCA for redundancy and variability. The study shows that introducing the PCA into the FSE can simplify the FSE calculation process greatly, while the results have not been changed much. 展开更多
关键词 Parameter Correlation Analysis (PCA) Fuzzy synthetic Evaluation (FSE) surface water quality Naoli River Sanjiang Plain
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Synthesis of Hyperbranched Polymers and Its Effect on Water Vapor Permeability of Microfiber Synthetic Leather 被引量:7
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作者 强涛涛 王学川 任龙芳 《Journal of Donghua University(English Edition)》 EI CAS 2010年第4期463-468,共6页
A series of hyperbranched poly(amine-ester)polyols were synthesized by the polycondensation of N,N-diethylol-3-amine-methylpropionate(prepared by Michael addition reaction of methyl acrylate with diethanolamine)as an ... A series of hyperbranched poly(amine-ester)polyols were synthesized by the polycondensation of N,N-diethylol-3-amine-methylpropionate(prepared by Michael addition reaction of methyl acrylate with diethanolamine)as an AB2-type monomer with trimethylol propane as the core moiety,proceeding in one-step procedure in the melt with p-toluenesulfonic acid as catalyst.The obtained monomer and polymers were characterized by FTIR and 1H-NMR spectroscopy.The solubility and surface activity in aqueous solution of the polymers were also examined.The gas permeability,water vapor permeability,and moisture absorption of microfiber synthetic leather treated by hyperbranched polymer were studied.The optimum conditions were that the dosage of dye and hyperbranched polymer was 5% and 10%,respectively.The water vapor permeability and moisture absorption of microfiber synthetic leather reached to 0.525 4 mg/(10 cm2·24 h)and 0.046 7 mg/(10 cm2·24 h).Compared with blank samples,they increased by 15% and 35%,respectively.However,the dosage of hyperbranched polymer has little influence on gas permeability of microfiber synthetic leather.SEM results show that the fiber of microfiber synthetic leather treated by hyperbranched polymer is incompact. 展开更多
关键词 hyperbranched polymer SYNTHESIS water vapor permeability MICROFIBER synthetic leather
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Synthetic Reconstruction of Water Demand Time Series for Real Time Demand Forecasting 被引量:3
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作者 Bruno M.Brentan Lubienska C.L.J.Ribeiro +2 位作者 Edevar Luvizotto Jr. Danilo C.Mendonca Jose M.Guidi 《Journal of Water Resource and Protection》 2014年第15期1437-1443,共7页
The forecasting of the demand applied to water supply systems has been an important tool to realize time control. The use of the time series to do the forecasting of the demand is the main way that has been used by re... The forecasting of the demand applied to water supply systems has been an important tool to realize time control. The use of the time series to do the forecasting of the demand is the main way that has been used by researchers. By this way, the need of a complete time demand series increases. This work presents two ways to reconstruct the water demand time series synthetically, using the Average Reconstruction Method and Fourier Method. Both the methods were considered interesting to do the synthetic reconstruction and able to complete the time series, but the Fourier Method showed better results and a better fitness to approximation of the water consumption pattern. 展开更多
关键词 water Demand Forecasting synthetic Reconstruction water Supply Systems
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Plasma Treatment for Preparing Durable Water Repellent and Anti-Stain Synthetic Fabrics for Automotive Applications
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作者 Nicoletta De Vietro Luca Belforte +2 位作者 Vito Lambertini Bartolomeo Placenza Francesco Fracassi 《Journal of Surface Engineered Materials and Advanced Technology》 2015年第3期103-109,共7页
This paper describes the development of a plasma process to produce a durable water repellent and anti-stain thin film on synthetic textile, utilized for the upholstery in the automotive field. The coatings were depos... This paper describes the development of a plasma process to produce a durable water repellent and anti-stain thin film on synthetic textile, utilized for the upholstery in the automotive field. The coatings were deposited in non equilibrium low pressure plasmas fed with 1H, 1H, 2H-perfluo-ro- 1-decene employing, as substrates, polyethylene terephthalate and polyethylene terephthalate thermo-coupled to polyurethane foam. It was found that the XPS F/C ratio of the deposit was higher than 1.4 and that the treated textile was always very hydrophobic (WCA > 140?) and oil resistant (motor oil CA > 110?), even after wear. 展开更多
关键词 synthetic Textile Automotive Durable water REPELLENT and Anti-Stain Character Low Pressure Plasma FLUORINATED Coating
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Determination of Organochlorine and Synthetic Pyrethroid Pesticide Residues in Water Samples Collected from Different Locations of Bangladesh
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作者 Mohammad Dalower Hossain Prodhan Md. Sultan Ahmed +2 位作者 Nirmal Kumar Dutta Debasish Sarker Syed Nurul Alam 《Journal of Biophysical Chemistry》 2021年第2期11-21,共11页
The present study was aimed to validate an analytical method for the quantification of 19 organochlorine and 2 synthetic pyrethroid pesticide residues in water samples using modified quick, easy, cheap, effective, rug... The present study was aimed to validate an analytical method for the quantification of 19 organochlorine and 2 synthetic pyrethroid pesticide residues in water samples using modified quick, easy, cheap, effective, rugged and safe (QuEChERS) extraction and Gas Chromatography coupled with Electron Capture Detector (ECD). The selected pesticide residues were determined by in-house validated method. The analytical method was validated by evaluating the accuracy, precision, linearity, limit of detection (LOD) and limit of quantification (LOQ). The average recoveries of the selected pesticides ranged from 78% to 117% with RSDr ≤ 12% in two fortification levels of 0.02 and 0.1 mg/L. The linearity was ≥0.995 for all of the selected pesticides. The LOD ranged from 0.003 to 0.006 mg/L and the LOQ was 0.02 mg/L for all the selected analytes. This method was applied satisfactorily for the residue analysis of 108 water samples collected from nine districts of Bangladesh. Among the analyzed samples, only 4 had cypermethrin residues (0.026 mg/L, 0.034 mg/L, 0.045 mg/L and 0.05 mg/L). The level of detected cypermethrin residues were above the WHO recommended guide line values of water quality. 展开更多
关键词 Organochlorine Pesticides synthetic Pyrethroid Pesticides water Samples Residue Analysis Gas Chromatography
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Development and Performance Evaluation of a Deep Water Synthetic Based Drilling Fluid System
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作者 Zengwei Chen Yongxue Lin +7 位作者 Ninghui Dou Chao Xiao Hua’an Zhou Yu Deng Yuqiao Zhou Song Wang Dichen Tan Huaiyuan Long 《Open Journal of Yangtze Oil and Gas》 2020年第4期165-175,共11页
With the enhancement of environmental protection awareness, the requirements on drilling fluid are increasingly strict, and the use of ordinary oil-based drilling fluid has been strictly restricted. In order to solve ... With the enhancement of environmental protection awareness, the requirements on drilling fluid are increasingly strict, and the use of ordinary oil-based drilling fluid has been strictly restricted. In order to solve the environmental protection and oil-gas reservoir protection problems of offshore oil drilling, a new synthetic basic drilling fluid system is developed. The basic formula is as follows: a basic fluid (80% Linear a-olefin + 20% Simulated seawater) + 2.5% nano organobentonite + 3.5% emulsifier RHJ-5<sup>#</sup> + 2.5% fluid loss agent SDJ-1 + 1.5% CaO + the right amount of oil wetting barite to adjust the density, and a multifunctional oil and gas formation protective agent YRZ has been developed. The performance was evaluated using a high-low-high-temperature rheometer, a high-temperature and high-pressure demulsification voltage tester, and a high-temperature and high-pressure dynamic fluid loss meter. The results show that the developed synthetic based drilling fluid has good rheological property, demulsification voltage ≥ 500 V, temperature resistance up to 160°C, high temperature and high pressure filtration loss < 3.5 mL. After adding 2% - 5% YRZ into the basic formula of synthetic based drilling fluid, the permeability recovery value exceeds 90% and the reservoir protection effect is excellent. The new synthetic deepwater drilling fluid is expected to have a good application prospect in offshore deepwater drilling. 展开更多
关键词 Deep water Drilling synthetic Based Drilling Fluid Rheological Property Emulsion Stability FILTRATION Agent of Reservoir Protection
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How synthetic microfibers end up in food & drinking water
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《China Textile》 2019年第5期44-45,共2页
No one sets out to refresh themselves by drinking plastic. But microscopic pollution are in virtually every body of water on Earth. While the debris comes from a number of sources, including food and drink packaging a... No one sets out to refresh themselves by drinking plastic. But microscopic pollution are in virtually every body of water on Earth. While the debris comes from a number of sources, including food and drink packaging and cosmetics, research is pointing to synthetic textile microfibers as a major culprit. Studies show hundreds of thousands of microplastic particles can enter the wa-ter supply just by laundering that polo shirt, midi dress or yoga pants. 展开更多
关键词 synthetic MICROFIBERS FOOD DRINKING water
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Utilization of Extracorporeal Membrane Oxygenation for Pulmonary Toxicity Caused by Inhaled Synthetic Cannabinoid. A Harbinger of Future Complications Associated with Inhaled Cannabinoid Products
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作者 Robert March Paul Guentert +17 位作者 Elizabeth Kloska-Kearney David Kwak Cody Yerger Michael McBride J. R. Majewski Ross McCauley Jordan Hatch Jacob Speybroeck Allen Betts Mat Marsee Sufyan Zackariya Faisal Shariff Shivani Patel Ali Sualeh Anthony Thomas Edward Evans Donald Westerhausen Mark Walsh 《International Journal of Clinical Medicine》 2020年第2期53-61,共9页
There has been a dramatic increase in medical complications related to synthetic cannabinoid (SC) use either by water pipe or vaping. The legalization of marijuana in an increasing number of states has also resulted i... There has been a dramatic increase in medical complications related to synthetic cannabinoid (SC) use either by water pipe or vaping. The legalization of marijuana in an increasing number of states has also resulted in an increase in a number of complications related not just to marijuana, but in particular, to SC. As a result, there have been recent increased reports of acute pulmonary injury related to inhaled SC products. We describe that rarely endotracheal intubation with mechanical ventilation has been required to treat the acute respiratory distress syndrome (ARDS) and the diffuse alveolar hemorrhage (DAH) associated with the acute toxicity of SC inhalation. We describe the second reported case of successful utilization of mechanical ventilation and extracorporeal membrane oxygenation (ECMO) in order to treat acute pulmonary toxicity caused by SC inhalation by a water pipe. While the exact pathophysiology of these interesting and recent pulmonary complications is unknown, the recent increase in exposure to SC via water pipe systems and vaping suggests that there will be many more cases of patients that will require ECMO as a form of life-saving therapy. 展开更多
关键词 synthetic CANNABINOID EXTRACORPOREAL Membrane OXYGENATION Mechanical Ventilation water Pipe Vaping PULMONARY Toxicity
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Factors affecting flocculation performance of synthetic polymer for turbidity control 被引量:1
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作者 Minyoung Kim Seounghee Kim +2 位作者 Jinoh Kim Sukwon Kang Sangbong Lee 《Journal of Agricultural Chemistry and Environment》 2013年第1期16-21,共6页
A multilateral effort into managing nonpoint source pollution from agriculture has gotten much attention for many years. Particularly during the heavy rain season, run-off of turbid water from sloped farmlands, fallow... A multilateral effort into managing nonpoint source pollution from agriculture has gotten much attention for many years. Particularly during the heavy rain season, run-off of turbid water from sloped farmlands, fallow ground and/or unmanaged uplands is deteriorated. Flocculant polymer, commonly used in wastewater treatment facilities, but now exploited to improve control of sediment turbidity by promoting flocculation of particles in construction site. This study used the flocculant polymer to control the discharge of agricultural nonpoint source pollution and focused on the understanding of how soil-water and polymer properties affect flocculation performance. Therefore, a series of flocculation experiments under different conditions was evaluated for better polymer clarification efficiency. Various factors such as flocculant dose, end-over-end inversion of a cylinder, and soil-water properties (pH, NaCl, organic matter) were studied. The effective flocculant dose that fulfilled fast settling rate was 10mg·L-1. Additional findings included that 1) increasing pH decreased the settling rate of soil particle;2) a positive relationship between the percentage of turbidity reduction and a level of salinity in Kaolin suspension was observed, and 3) organic matter in soil solution inhibited PAM adsorption onto soil particles, which caused the reduction of flocculation performance. The findings of this study revealed that flocculant polymer possess good results as a turbidity reducetion measure and couldfurther provide valuable information to make better decision on establishment of Best Management Practice for handling agricultural nonpoint source pollution. 展开更多
关键词 AGRICULTURAL Nonpoint Source POLLUTION FLOCCULATION synthetic Polymer TURBIDITY CONTROL SOIL-water Properties
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Application of Synthetic Meteorological Time Series in BROOK90:A Case Study for the Tharandt Forest in Saxony,Germany
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作者 Kronenberg Rico Güttler Tino +1 位作者 Franke Johannes Bernhofer Christian 《Open Journal of Modern Hydrology》 2013年第4期214-225,共12页
This study presents an extended version of a single site daily weather generator after Richardson. The model is driven by daily precipitation series derived by a first-order two-state Markov chain and considers the an... This study presents an extended version of a single site daily weather generator after Richardson. The model is driven by daily precipitation series derived by a first-order two-state Markov chain and considers the annual cycle of each meteorological variable. The evaluation of its performance was done by deploying its synthetic time series into the physical based hydrological model BROOK90. The weather generator was applied and tested for data from the Anchor Station at the Tharandt Forest, Germany. Additionally its results were compared to the output of another weather generator with spell-length approach for the precipitation series (LARS-WG). The comparison was distinguished into a meteoro-logical and a hydrological part in terms of extremes, monthly and annual sums and averages. Extreme events could be preserved adequately by both models. Nevertheless a general underestimation of rare events was observed. Natural correlations between vapour pressure and minimum temperature could be conserved as well as annual cycles of the hydro-logical and meteorological regime. But the simulated spectrums of extremes, especially, of precipitation and temperature, are more limited than the observed spectrums. While LARS-WG already finds application in practice, the results show that the data derived from the presented weather generator is as useful and reliable as those from the established model for the simulation of the water balance. 展开更多
关键词 Richardson Model Weather Generator BROOK90 synthetic Time Series LARS-WG Forest water Balance Taylor Diagram Cumulative Periodogram
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A History of Fischer-Tropsch Wax Upgrading at BP-from Catalyst Screening Studies to Full Scale Demonstration in Alaska 被引量:5
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作者 John P. Collins Joep J. H. M. Font Freide Barry Nay 《Journal of Natural Gas Chemistry》 CAS CSCD 2006年第1期1-10,共10页
Conversion of Fischer-Tropsch wax into high quality synthetic crude or finished transportation fuels such as premium diesel has been studied over the past 15 years within BP. Catalyst screening and selection was carri... Conversion of Fischer-Tropsch wax into high quality synthetic crude or finished transportation fuels such as premium diesel has been studied over the past 15 years within BP. Catalyst screening and selection was carried out in dedicated micro-reactors and pilot plants, whose designs are critical to the performance selection. Variation in catalyst composition and defining the gas to oil feed ratios with the operating temperature are a few of the parameters studied. Product selection and maximizing diesel yield combined with stability (catalyst life) were the ultimate drivers. The selected catalyst was then tested under commercial conditions in a dedicated 300 barrel per day demonstration plant. The products were also tested in engines to assess their combustion characteristics. 展开更多
关键词 fischer-tropsch wax upgrading HYDROCRACKING synthetic crude diesel NAPHTHA engine emission
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Recent advances of transition-metal metaphosphates for efficient electrocatalytic water splitting 被引量:2
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作者 Yuanyuan Zhang Jie Wu +4 位作者 Bingrong Guo Haohao Huo Siqi Niu Siwei Li Ping Xu 《Carbon Energy》 SCIE EI CAS CSCD 2023年第12期153-174,共22页
Sustainable production of H2 through electrochemical water splitting is of great importance in the foreseeable future.Transition-metal metaphosphates(TMMPs)have a three-dimensional(3D)open-framework structure and a hi... Sustainable production of H2 through electrochemical water splitting is of great importance in the foreseeable future.Transition-metal metaphosphates(TMMPs)have a three-dimensional(3D)open-framework structure and a high content of P(which exists as PO3-),and therefore have been recognized as highly efficient catalysts for oxygen evolution reaction(OER)and the bottleneck of electrochemical water splitting.Furthermore,TMMPs can also contribute to hydrogen evolution reaction(HER)in alkaline and neutral media by facilitating water dissociation,and thus,overall water splitting can be achieved using this kind of material.In this timely review,we summarize the recent advances in the synthesis of TMMPs and their applications in OER and HER.We present a brief introduction of the structure and synthetic strategies of TMMPs in the first two parts.Then,we review the latest progress made in research on TMMPs as OER,HER,and overall water-splitting electrocatalysts.In this part,the intrinsic activity of TMMPs as well as the current strategy for improving the catalytic activity will be discussed systematically.Finally,we present the future opportunities and the remaining challenges for the application of TMMPs in the electrocatalysis field. 展开更多
关键词 ELECTROCATALYSIS synthetic strategies transition-metal metaphosphates water splitting
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Application of Fuzzy Mathematics to the Evaluation of Drinking Water Quality in Wuhan
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作者 袁晶 陈秀娜 汪蓉 《Journal of Huazhong University of Science and Technology(Medical Sciences)》 SCIE CAS 1996年第1期25-26,共2页
The quality of raw water from major water plants in Wuhan was evaluated by using Fuzzy synthetic evaluation model.It is suggested to select the alternative synthetic evaluation model when the first Fuzzy synthetic mod... The quality of raw water from major water plants in Wuhan was evaluated by using Fuzzy synthetic evaluation model.It is suggested to select the alternative synthetic evaluation model when the first Fuzzy synthetic model failed in order to increase accuracy. 展开更多
关键词 drinking water Fuzzy mathematics synthetic evaluation method
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运动器材用水性聚氨酯合成革胶膜制备及其性能研究
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作者 卢瑛 《中国皮革》 CAS 2024年第7期154-158,共5页
为改善运动器材用水性聚氨酯合成革综合性能,本文以聚丙二醇2000与二月桂酸二丁基锡为原料,以硅烷偶联剂为改性剂制备了水性聚氨酯合成革胶膜,并对其性能进行了测试表征。结果表明,随着硅烷偶联剂用量增加,合成革用水性聚氨酯乳液由透... 为改善运动器材用水性聚氨酯合成革综合性能,本文以聚丙二醇2000与二月桂酸二丁基锡为原料,以硅烷偶联剂为改性剂制备了水性聚氨酯合成革胶膜,并对其性能进行了测试表征。结果表明,随着硅烷偶联剂用量增加,合成革用水性聚氨酯乳液由透明变为白色,粒径逐渐增大,黏度逐步增大,离心稳定性较好;随着硅烷偶联剂用量增加,水性聚氨酯合成革胶膜拉伸强度与断裂伸长率均先增后减,杨氏模量先缓慢增大后迅速增大,剥离强度先增后减,当用量为6 g时胶膜力学性能整体表现最优;随着硅烷偶联剂用量增加,水性聚氨酯合成革胶膜吸水率先减后增,水接触角逐渐增大,当用量为6 g时胶膜耐水性能整体表现最佳。 展开更多
关键词 水性聚氨酯 合成革 胶膜 乳液 耐水性能
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超细纤维合成革透水汽性能的研究进展 被引量:7
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作者 闫子妍 赵立环 +3 位作者 王玉稳 杨玉洁 李艳艳 陈雨龙 《皮革科学与工程》 CAS 北大核心 2024年第1期61-68,100,共9页
超细纤维合成革(简称超纤革)是替代天然皮革的理想材料,但超纤革的透水汽性能与天然皮革相比仍存在差距,有待提升。文章概述了超纤革的制备过程,分析了超纤革的性能及其在透水汽性能方面的不足,并从超纤革的主要组分,即超纤革基布和聚... 超细纤维合成革(简称超纤革)是替代天然皮革的理想材料,但超纤革的透水汽性能与天然皮革相比仍存在差距,有待提升。文章概述了超纤革的制备过程,分析了超纤革的性能及其在透水汽性能方面的不足,并从超纤革的主要组分,即超纤革基布和聚氨酯树脂入手,探讨了超纤革透水汽性能研究的最新进展;总结了对超纤革基布的水解、增加活性基团和亲水剂等改性方法,阐述了对聚氨酯树脂的填料、接枝聚合和共混等改性措施,探讨了对超纤革的后整理改性选项,最后提出了超纤革透水汽性能研究的未来发展方向。 展开更多
关键词 超细纤维合成革 透水汽性能 革基布 聚氨酯树脂 改性
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碳化钼的结构、制备及应用研究进展 被引量:1
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作者 邓开鑫 刘澄虎 +3 位作者 于志庆 黄文斌 魏强 周亚松 《材料导报》 EI CAS CSCD 北大核心 2024年第5期120-137,共18页
将碳原子引入钼的晶格中形成碳化钼时,形成的间充结构具有独特的物理和化学性质,在加氢反应和制氢反应等领域具有优异的催化性能,可与贵金属铂、钯相媲美。碳化钼化学性质活泼,合成方法和实验条件都密切影响着最终产品的物化性质,任何... 将碳原子引入钼的晶格中形成碳化钼时,形成的间充结构具有独特的物理和化学性质,在加氢反应和制氢反应等领域具有优异的催化性能,可与贵金属铂、钯相媲美。碳化钼化学性质活泼,合成方法和实验条件都密切影响着最终产品的物化性质,任何一种反应原料和实验条件发生微小变化,都可能造成碳化钼的晶相结构、晶粒大小、比表面积等产生较大变化,从而改变材料的催化性质。本文对几种典型碳化钼的晶相类型及空间结构分别进行了介绍,分析了影响碳化钼结构的电子性质和几何因素,系统总结了碳化钼的合成策略并指出了不同制备方法的优劣势。以程序升温还原法为例,分析了碳化钼的生长机理,并从碳化终温、升温速率、碳源浓度三方面着重讨论了制备条件对材料的影响。然后总结了碳化钼在加氢反应、制氢反应、传感器及生物医学材料等领域的应用,详细阐述了碳化钼在电催化析氢和CO_(2)加氢转化反应中的催化机理及改进策略,最后基于目前存在的挑战进一步提出碳化钼材料未来的发展方向。 展开更多
关键词 碳化钼 晶体结构 程序升温还原法 合成策略 电解水析氢 三维材料
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基于梯度提升决策树模型的Sentinel-1图像浅海水深反演
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作者 黄茂苗 魏永亮 +3 位作者 唐泽艳 刘浩 袁文枭 袁新哲 《海洋科学》 CAS CSCD 北大核心 2024年第4期1-17,共17页
利用合成孔径雷达(Synthetic Aperture Radar,SAR)反演浅海水深在海洋遥感中极具挑战性。本文采用梯度提升决策树(Gradient Boosting Decision Tree,GBDT)为核心的机器学习算法,使用Sentinel-1、全球水深数据、风场和流场数据来反演杭... 利用合成孔径雷达(Synthetic Aperture Radar,SAR)反演浅海水深在海洋遥感中极具挑战性。本文采用梯度提升决策树(Gradient Boosting Decision Tree,GBDT)为核心的机器学习算法,使用Sentinel-1、全球水深数据、风场和流场数据来反演杭州湾和长江口南缘相连的浅海区域的水深。首先分析反演的最佳风速和迭代次数,再对0~10 m、10~20 m、20~30 m、30~40 m、40~50 m的分段水深和0~10 m、0~20 m、0~30 m、0~40 m、0~50 m的总体水深用相关系数、均方根误差和平均绝对误差进行精度评价,最后分析反演水深的空间分布特征。结果表明:反演的最佳风速约为3.78 m/s,并且GBDT模型达到最佳精度时的迭代次数远小于其他模型,最佳迭代次数为4。分段水深中,40 m以内的相关系数都高于0.8,其中以10~20 m的相关系数最高,为0.9;40~50 m则最低,为0.73。40~50 m的平均绝对误差和均方根误差均为最大,分别为1.89 m和2.24 m,20~30 m的平均绝对误差和均方根误差均为最小,分别为0.75 m和0.96 m。在总体水深中,虽然随水深区间的扩大,相关系数会逐渐增加,但是平均绝对误差和均方根误差的精度都随水深区间的扩大而下降,且在0~50 m区间内的平均绝对误差和均方根误差最大,分别为1.06 m和1.59 m,因此反演的最佳区间为0~40 m。该区域的水深从杭州湾海岸线开始由浅及深阶梯增加,反演结果能够较好的表现研究区内的实际水深分布情况,比较符合当前区域的水下地形特征。 展开更多
关键词 遥感 合成孔径雷达 水深 梯度提升决策树 迭代
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HPHT法合成人造金刚石用粉末触媒的发展与研究
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作者 田龙 谷年良 +6 位作者 毕涵 蒋鑫 马春生 高莹 王增辉 魏华阳 王玉宝 《超硬材料工程》 CAS 2024年第2期33-39,共7页
研究了HPHT法合成人造金刚石用粉末触媒的制备方法,主要有雾化法、化学共沉淀法和羰基法,其中雾化法又分为气雾化法和水雾化法。水雾化法粉末触媒的合金成分均匀,工艺简单,设备要求低,推广容易,出粉率和成品率高,生产成本低,因此水雾化... 研究了HPHT法合成人造金刚石用粉末触媒的制备方法,主要有雾化法、化学共沉淀法和羰基法,其中雾化法又分为气雾化法和水雾化法。水雾化法粉末触媒的合金成分均匀,工艺简单,设备要求低,推广容易,出粉率和成品率高,生产成本低,因此水雾化法是HPHT法合成人造金刚石用粉末触媒的普遍工艺。人工晶体研究院研发并推广了水雾化法粉末触媒,推动了中国人造金刚石行业和超硬材料行业的发展。在水雾化法制备粉末触媒的基础上,研究了收料工艺对水雾化法FeNi_(30)粉末触媒的影响。研究发现:采用沉淀放水工艺时粉末触媒氧含量、杂质含量和物料损失均远低于传统滤布收料工艺;从微观形貌分析,沉淀放水工艺粉末触媒球形度高,异形率和异形度低。沉淀放水工艺粉末触媒制备的人造金刚石TI (冲击韧性)、TTI (热冲击韧性)、晶型、透度和颜色均优于传统滤布收料工艺。 展开更多
关键词 HPHT 人造金刚石 粉末触媒 水雾化
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合成氨装置低温甲醇洗系统贫甲醇含水量升高的原因分析及对策
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作者 霍其雷 尤永平 李伟 《石化技术与应用》 CAS 2024年第3期216-220,共5页
针对中国石油吉林石化公司30万t/a合成氨装置在新增合成气净化系统的工艺改造后,低温甲醇洗系统贫甲醇含水量(质量分数,下同)异常升高(高达2.6%)并超过设计指标值(1.5%),不得不降负荷运行的情况,排查了相关影响因素,分析了导致甲醇/水... 针对中国石油吉林石化公司30万t/a合成氨装置在新增合成气净化系统的工艺改造后,低温甲醇洗系统贫甲醇含水量(质量分数,下同)异常升高(高达2.6%)并超过设计指标值(1.5%),不得不降负荷运行的情况,排查了相关影响因素,分析了导致甲醇/水分离塔塔板筛孔堵塞的原因,并实施了相应的工艺优化措施。结果表明:工艺优化措施实施后,大幅改善了甲醇/水分离塔的分离效果,不仅使该装置低温甲醇洗系统负荷率由82%提升至100%,还使贫甲醇含水量降低至0.4%。 展开更多
关键词 合成氨装置 低温甲醇洗系统 甲醇/水分离 贫甲醇含水质量分数 异常升高 塔板堵塞 优化措施
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基于云计算的引调水工程星载TD-InSAR地表形变监测
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作者 万鹏 韩贤权 +1 位作者 谭勇 秦朋 《长江科学院院报》 CSCD 北大核心 2024年第10期206-214,共9页
针对时间序列InSAR计算量大、时效性低、传统D-InSAR精度不高的问题,提出了TD-InSAR连续像对干涉测量方法,并利用HyP3云计算平台实现了长距离引调水工程沿线地表形变连续干涉像对快速分析。以珠江三角洲水资源配置工程为研究区,以传统PS... 针对时间序列InSAR计算量大、时效性低、传统D-InSAR精度不高的问题,提出了TD-InSAR连续像对干涉测量方法,并利用HyP3云计算平台实现了长距离引调水工程沿线地表形变连续干涉像对快速分析。以珠江三角洲水资源配置工程为研究区,以传统PS-InSAR监测结果为参照数据对TD-InSAR地表形变探测精度进行了验证。试验结果表明:TD-InSAR取得的地表形变速率与PS-InSAR趋势一致,决定系数R 2>0.7,精度相比传统D-InSAR方法提高了52.6%;基于云计算的TD-InSAR地表形变监测方法降低了时序分析的计算量,提高了时序分析的时效性,适用于大范围的地表形变快速普查分析。 展开更多
关键词 地表形变监测 合成孔径雷达干涉测量(InSAR) 引调水工程 HyP3云计算平台 地表形变快速普查
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