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Characteristics and Influencing Factors of Microplastics in Snow in the Inner Mongolia Plateau, China 被引量:1
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作者 Hongwei Yu Junrong Shao +3 位作者 Huawei Jia Diga Gang Baiwen Ma Chengzhi Hu 《Engineering》 SCIE EI CAS CSCD 2024年第6期69-77,共9页
Microplastics(MPs;<5 mm)have become one of the most prominent global environmental pollution problems.MPs can spread to high altitudes through atmospheric transport and can be deposited by rainfall or snowfall,pote... Microplastics(MPs;<5 mm)have become one of the most prominent global environmental pollution problems.MPs can spread to high altitudes through atmospheric transport and can be deposited by rainfall or snowfall,potentially threatening the structure and function of natural ecosystems.MPs in terrestrial and aquatic ecosystems alter the growth and functional characteristics of organisms.However,little attention has been given to the possible harm associated with MPs deposited in snow,particularly in the context of global climate warming.MPs collected from surface snow in the Inner Mongolia Plateau,China,were used for quantitative analysis and identification.The results showed that MPs were easily detected,and the related concentration was approximately(68±10)–(199±22)MPsL1 in snow samples.Fibers were the most common morphology,the polymer composition was largely varied,and the abundance and composition of MPs were linked to human activity to a great extent.High-throughput sequencing results showed that the composition and abundance of microorganisms also differed in snow samples from areas with different MP pollution characteristics,indicating a considerable difference in microbial functional diversity.MPs may have an interference effect on the individual growth and functional expression of microorganisms in snow.In addition,the results showed that functional living areas(e.g.,landfills and suburban areas)in cities play an important role in the properties of MPs.For instance,the highest abundance of MPs was found in thermal power plants,whereas the abundance of polymers per sample was significantly lower in the suburban area.The MP contaminants hidden in snow can alter microbial structure and function and are therefore a potential threat to ecosystem health. 展开更多
关键词 Human activities snow Microplastics Microbial community Urban function Environmental effect
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Observed and modelled snow and ice thickness in the Arctic Ocean with CHINARE buoy data 被引量:4
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作者 TIAN Zhongxiang CHENG Bin +4 位作者 ZHAO liechen VIHMA Timo ZHANG Wenliang LI Zhijun ZHANG Zhanhai 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2017年第8期66-75,共10页
Sea ice and the snow pack on top of it were investigated using Chinese National Arctic Research Expedition (CHINARE) buoy data. Two polar hydrometeorological drifters, known as Zeno ice stations, were deployed durin... Sea ice and the snow pack on top of it were investigated using Chinese National Arctic Research Expedition (CHINARE) buoy data. Two polar hydrometeorological drifters, known as Zeno ice stations, were deployed during CHINARE 2003. A new type of high-resolution Snow and Ice Mass Balance Arrays, known as SIMBA buoys, were deployed during CHINARE 2014. Data from those buoys were applied to investigate the thickness of sea ice and snow in the CHINARE domain. A simple approach was applied to estimate the average snow thickness on the basis of Zeno temperature data. Snow and ice thicknesses were also derived from vertical temperature profile data based on the SIMBA buoys. A one-dimensional snow and ice thermodynamic model (HIGHTSI) was applied to calculate the snow and ice thickness along the buoy drift trajectories. The model forcing was based on forecasts and analyses of the European Centre for Medium-Range Weather Forecasts (ECMWF). The Zeno buoys drifted in a confined area during 2003-2004. The snow thickness modelled applying HIGHTSI was consistent with results based on Zeno buoy data. The SIMBA buoys drifted from 81. 1°N, 157.4°W to 73.5°N, 134.9°W in 15 months during 2014-2015. The total ice thickness increased from an initial August 2014 value of 1.97 m to a maximum value of 2.45 in before the onset of snow melt in May 2015; the last observation was approximately 1 m in late November 2015. The ice thickness based on HIGHTSI agreed with SIMBA measurements, in particular when the seasonal variation of oceanic heat flux was taken into account, but the modelled snow thickness differed from the observed one. Sea ice thickness derived from SIMBA data was reasonably good in cold conditions, but challenges remain in both snow and ice thickness in summer. 展开更多
关键词 TEMPERATURE snow sea ice thickness ice mass balance buoy Arctic ocean
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Toxic Effects of Phthalates on Ocean Algae 被引量:1
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作者 邱海源 王宪 《Marine Science Bulletin》 CAS 2005年第2期91-96,共6页
This article discusses the interaction of phthalates and ocean algae based on the standard appraisal method of chemical medicine for algae toxicity. Through the experiments on the toxic effects of dimethyl (o-) phthal... This article discusses the interaction of phthalates and ocean algae based on the standard appraisal method of chemical medicine for algae toxicity. Through the experiments on the toxic effects of dimethyl (o-) phthalate (DMP), diethyl (o-) phthalate (DEP), dibutyl (o-) phthalate (DBP) on ocean algae, the 50 % lethal concentration of the three substances in 48 h and 96 h for plaeodectylum tricornutum, platymonas sp, isochrysis galbana, and skeletonema costatum is obtained. Tolerance limits of the above ocean algae of DMP, DEP, and DBP are discussed. 展开更多
关键词 邻苯二甲酸盐 海藻 毒性 有机物 环境保护 海洋污染
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THE FEATURES OF SEA-ICE COVER, SNOW DISTRIBUTION AND ITS DENSIFICATION IN THE CENTRAL ARCTIC OCEAN
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作者 效存德 秦大河 任贾文 《Chinese Geographical Science》 SCIE CSCD 1997年第4期317-327,共11页
Based on the observation of sea-ice cover and measurement of snow depths and stratigraphy during China’s First North Pole Sientific Expedition, three types of surface topography of sea ice and correspondingly three c... Based on the observation of sea-ice cover and measurement of snow depths and stratigraphy during China’s First North Pole Sientific Expedition, three types of surface topography of sea ice and correspondingly three categories of snow distribution in the central Arctic are classified. It is considered that the classification will help to determine the sites for snow depth measurement, stratigraphy Observation and snowpits sampling. The snow cover is slowly accumulated during the long Arctic winter, approximately from September to early May next year, while its ablation shows abrupt from south to north. By the end of August, the snow cover is alment totally removed. The spatial distribution of snow depth is characterized by a northwardly decreasing trend, which is proposed to result from the remote vapour sources, i. e., the major vapour over the Arctic regions is transported from mid-latitudes. The stratigraphy of the snompits are characterized by the extensively existed depth hoar at the deeper part of the pits, which is probably a signal of the beginning of the long Arctic winter.The present of infiltration-congelation ice adhering to sea ice surface at the end of the ablation indicates that the annual accumulation is approximately equals to the annual ablation near north pole. 展开更多
关键词 ARCTIC ocean SEA-ICE COVER snowPACK snow STRATIGRAPHY
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Effect of nonlinear advection on the Indian Ocean diploe asymmetry
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作者 WANG Yu LAN Jian CUI Fengjuan 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2014年第1期77-82,共6页
The asymmetry of sea surface temperature anomaly(SSTA) amplitudes between the positive and negative phases of the Indian Ocean dipole(IOD) are studied.The dynamic effects on it are analyzed using a hybrid coordina... The asymmetry of sea surface temperature anomaly(SSTA) amplitudes between the positive and negative phases of the Indian Ocean dipole(IOD) are studied.The dynamic effects on it are analyzed using a hybrid coordinate ocean model(HYCOM).It suggests that the IOD is still asymmetric even when forced by a symmetric wind stress,and the asymmetry of the SSTA in the eastern pole is strong while that in the western pole is almost insignificant during the mature phase(September–November(SON)).Thus,the IOD asymmetry is primarily caused by the asymmetry in the IODE.A heat budget analysis is also conducted for the mixedlayer temperature in the eastern Indian Ocean(IODE),which indicates that a nonlinear ocean advection cools both the positive and negative IOD events.Therefore,the nonlinear ocean advection is responsible for the asymmetry of the IOD. 展开更多
关键词 asymmetry of Indian ocean dipole dynamical effect heat budget nonlinear advection
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Effective Elastic Thickness of Southeast Part ofArctic Ocean-Eurasia Continent-PacificOcean Geoscience Transect
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作者 YuanBingqiang YvetteHPoudjomDjomani 《Journal of China University of Geosciences》 SCIE CSCD 2002年第1期20-25,共6页
The effective lithospheric elastic thickness of the continent is an important parameter for examination of the large-scale structure and analyses of the mechanism of isostatic compensation within the plate, and a para... The effective lithospheric elastic thickness of the continent is an important parameter for examination of the large-scale structure and analyses of the mechanism of isostatic compensation within the plate, and a parameter standing for the strength of the lithosphere. The Te values along Quanzhou-Heishui, the southeast section of the Arctic Ocean-Eurasian Continent-Pacific Ocean geoscience transect, are estimated by using the coherence technique developed by Forsyth. Studies of the feature of the coherence between gravity and topography suggest that at short wavelengths (6. 6-100 km) for each data box that is used to estimate Te, the plate is strong enough to support topographic loads and gravity and topography are uncorrelated. At long wavelengths where the plate is deflected by surface and subsurface loads are compensated by the flexure model. Sichuan land-stone with low heat-flow values has high Te values whereas in Ninghua, Datian, land-stone with high heat-flow values has low Te values, which reflects a correlation, low heat-flow values corresponding to high Te values and high heat-flow values corresponding to low Te values. Te values can be divided into two sections: northwest high section and southeast low section. There is roughly a positive correlation between crustal thickness and effective elastic thickness of the lithosphere. 展开更多
关键词 effective elastic thickness coherence technique Arctic ocean-Eurasia Continent-Pacific ocean geoscience transect.
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Regional Oceanic Impact on Circulation and Direct Radiative Effect of Aerosol over East Asia 被引量:1
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作者 XIONG Zhe HAN Zhi-Wei 《Atmospheric and Oceanic Science Letters》 2011年第6期324-329,共6页
The Regional Integrated Environmental Model System(RIEMS 2.0) coupled with a chemistry-aerosol model and the Princeton Ocean Model(POM) is employed to simulate regional oceanic impact on atmospheric circulation and th... The Regional Integrated Environmental Model System(RIEMS 2.0) coupled with a chemistry-aerosol model and the Princeton Ocean Model(POM) is employed to simulate regional oceanic impact on atmospheric circulation and the direct radiative effect(DRE) of aerosol over East Asia.The aerosols considered in this study include both major anthropogenic aerosols(e.g.,sulfate,black carbon,and organic carbon) and natural aerosols(e.g.,soil dust and sea salt) .The RIEMS 2.0 is driven by NCEP/NCAR reanalysis II,and the simulated period is from 1 January to 31 December 2006.The results show the following:(1) The simulated annual mean sea-level pressure by RIEMS 2.0 with POM is lower than without POM over the mainland and higher without POM over the ocean.(2) In summer,the subtropical high simulated by RIEMS 2.0 with POM is stronger and extends further westward,and the continental low is stronger than without POM in summer.(3) The aerosol optical depth(AOD) simulated by RIEMS 2.0 with POM is larger in the middle and lower reaches of the Yangtze River than without POM.(4) The direct radiative effect with POM is stronger than that without POM in the middle and lower reaches of the Yangtze River and parts of southern China. Therefore,the authors should take account of the impact of the regional ocean model on studying the direct climate effect of aerosols in long term simulation. 展开更多
关键词 气溶胶光学厚度 海洋模型 辐射效应 东亚地区 流通 区域海洋模式 模型系统 POM
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Effect of Ocean Thermal Diffusivity on Global Warming Induced by Increasing Atmospheric CO_2
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作者 包宁 张学洪 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 1991年第4期421-430,共10页
A global mean ocean model including atmospheric heating, heat capacity of the mixed layer ocean, and vertical thermal diffusivity in the lower ocean, proposed by Cess and Goldenberg (1981), is used in this paper to st... A global mean ocean model including atmospheric heating, heat capacity of the mixed layer ocean, and vertical thermal diffusivity in the lower ocean, proposed by Cess and Goldenberg (1981), is used in this paper to study the sensitivity of global warming to the vertical diffusivity. The results suggest that the behaviour of upper ocean temperature is mainly determined by the magnitude of upper layer diffusivity and an ocean with a larger diffusivity leads to a less increase of sea surface temperature and a longer time delay for the global warming induced by increasing CO2 than that with smaller one. The global warming relative to four scenarios of CO2 emission assumed by Intergovernmental Panel of Climate Change (IPCC) is also estimated by using the model with two kinds of thermal diffusivities. The result shows that for various combinations of the CO2 emission scenarios and the diffusivities, the oceanic time delay to the global warming varies from 15 years to 70 years. 展开更多
关键词 effect of ocean Thermal Diffusivity on Global Warming Induced by Increasing Atmospheric CO2 CO
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Effect of 30%Xiange Oceanic Bioactive Peptide Pesticide-Fertilizer on Sugarcane Pests,Sugarcane Yield and Sugar
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作者 Xie Jiangjiang Luo Qingwen +5 位作者 Wu Guan Yuan Dongliang Luo Yi Ma Lizhen Yang Ganling Yang Junxian 《Plant Diseases and Pests》 CAS 2020年第2期23-27,共5页
[Objective]The paper was to study the effect of 30%Xiange oceanic bioactive peptide pesticide-fertilizer on sugarcane pests,sugarcane yield and sugar.[Method]With conventional compound fertilizer mixed with 3%carbofur... [Objective]The paper was to study the effect of 30%Xiange oceanic bioactive peptide pesticide-fertilizer on sugarcane pests,sugarcane yield and sugar.[Method]With conventional compound fertilizer mixed with 3%carbofuran granulated insecticide as the control,the field effect of30%Xiange pesticide-fertilizer on sugarcane was compared.[Result]After the application of 30%Xiange pesticide-fertilizer for 90 d,the control effects on sugarcane borers in the two test points were 93.66%and 93.09%,respectively,which were significantly higher than those of conventional control(21.86%and 24.19%).Before harvest,the reduction effects of sugarcane internodes in the two test points treated by pesticide-fertilizer were6.21%and 5.10%,respectively,which were significantly lower than those of conventional control(36.25%and 34.55%).The control effects of Xiange pesticide-fertilizer on sugarcane chafer in the two test points were 91.34%and 100.00%respectively,which were significantly higher than those of conventional control(68.00%and 64.29%).The yields of sugarcane treated by Xiange pesticide-fertilizer in the two test points were107700 and 108000 kg/hm2,and the sugar contents were 15.62%and 15.55%,respectively.The yield and sugar content of sugarcane treated by Xiange pesticide-fertilizer were increased by 28.63%and 1.33%compared with those of conventional control.[Conclusion]30%Xiange oceanic bioactive peptide pesticide-fertilizer has good control effect on sugarcane pests,which could obviously increase yield and sugar of sugarcane.The product is worth being promoted and applied in sugarcane planting area. 展开更多
关键词 oceanic bioactive peptide pesticide-fertilizer Sugarcane pests Control effect YIELD Sugar content of sugarcane
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Effect of ocean environmental factors on sound absorption by boric acid relaxation in sea water
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作者 Qiu Xinfang( Received May 17, 1990 accepted August 20, 1990) 《Acta Oceanologica Sinica》 SCIE CAS CSCD 1991年第2期271-280,共10页
By using the expressions for the maximum absorption per wavelength (αλ),and the relaxation frequency fr of the boric acid relaxation derived previously by the author and employing the related oceanographic literatur... By using the expressions for the maximum absorption per wavelength (αλ),and the relaxation frequency fr of the boric acid relaxation derived previously by the author and employing the related oceanographic literatures, the effects of pressure, temperature, pH and salinity on (αλ)r and ∫r of the boric acid relaxation in sea water have been estimated. Results show that ( αλ), not only increases with pH but also increases approximately linearly with pressure and temperature, and is nearly proportional to the 1. 35 power of salinity. However, pressure, pH and salinity have negligible effect on ∫r; therefore, ∫r, can be approximately expressed as a function of temperature only. Comparisons of the predicted with the measured ( αλ)r and ∫r in different ocean areas are given. 展开更多
关键词 effect of ocean environmental factors on sound absorption by boric acid relaxation in sea water ACID
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Abnormality of thermal structure and current in the upper western tropical Pacific Ocean and its effect on subtropical high
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作者 Pu Shuzhen Yu Huiling First Institute of Oceanography, State Oceanic Administration, P. O. Box 98, Qingdao 266003, China 《Acta Oceanologica Sinica》 SCIE CAS CSCD 1992年第1期67-82,共16页
-Mainly on the basis of the data obtained during PRC/US bilateral TOGA cruises, abnormal variation occurred during the 1986/1987 El Nino is shown in this paper about the thermal structure and circulation of the upper ... -Mainly on the basis of the data obtained during PRC/US bilateral TOGA cruises, abnormal variation occurred during the 1986/1987 El Nino is shown in this paper about the thermal structure and circulation of the upper western tropical Pacific Ocean. The effects of the abmormal variation on the subtropical high over the Northwest Pacific Ocean are discussed. During the El Nino: (1) In the east part of the western tropical Pacific Ocean (the subsurface temperature data on the 165° E section are taken as an example), the water wanner than 29 C in the upper layer spread on the longitudinal section and positive temperature anormalies appeared in a large area of the sea surface. (2) In the west part of the western tropical Pacific Ocean (the subsurface temperature data on the 137°E section are representative ), the cross section occupied by the upper layer warmer water ( T >28 ℃ ) became shrunk, and the sea surface temperature showed negative amomalies. (3) The eastward flows in the upper layer of the 165°E section strengthened. (4)The northward flow volume of warm water from the origin area of Kuroshio, i. e. , the tropical oceanic area south of 18?0' N and from the west of 130?E to the Philippine coast, decreased. When those kinds of abnomal variation occurred, air divergence on the low level (1 000 hPa) over the Northwest Pacific Ocean was intensified, favourable to the strengthening of subtropical high over the Northwest Pacific Ocean. 展开更多
关键词 Abnormality of thermal structure and current in the upper western tropical Pacific ocean and its effect on subtropical high Nino
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Towards an Effective Communication in the Care of Patients with Long Term Disease in Kenya via Cybernetic—A Systematic Review
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作者 Christopher Oyuech Otieno Martha W. Kiarie Makara +1 位作者 Naomi N. James Grace Mbogo Liyai 《Open Journal of Applied Sciences》 2023年第11期2094-2126,共33页
In this paper, to effectively treat chronic disorders and improve the standard of care, effective communication between patients and healthcare professionals was essential. The aim of the study was to review the liter... In this paper, to effectively treat chronic disorders and improve the standard of care, effective communication between patients and healthcare professionals was essential. The aim of the study was to review the literature on how good communication might improve treatment outcomes for Kenyan patients with chronic and terminal illnesses and to determine whether Cybernetic electronic communication can improve those outcomes even more. We uncovered the history of treatment outcomes for chronic and terminal diseases in this research study, both with and without communication at the core of the patient’s care plan. We discussed the importance of good communication in the treatment of patients with chronic and terminal illnesses and why it is a momentous endeavor comparable to medical diagnosis and treatment for the long-term health of patients. To locate pertinent material for the background literature study, we carried out a comprehensive literature search. Although the preliminary literature review was a continuation of the introduction research, it also highlighted the paucity of local Kenyan literature and suggested that improved communication might help patients with chronic and terminal illnesses have better treatment outcome. Methodology maintained the literature search, as a systematic literature review focused on core of the study, making separate sections of the same body necessary. This ensured that a methodological literature search section is as comprehensive as possible. We used an integrated PRISM model to limit a comprehensive literature search and a systematic literature review design as part of the overall process. Non-probability sampling and snowball approaches on literary papers over the previous 17 years were used in this arrangement. Since this was a multidisciplinary study, the four experts who also serve as authors were chosen from within their respective fields of expertise to design the study. They created search strategies, generated key words, looked up keywords in database engines, assessed the results of the literature using the PRISMA logical model, looked over successful literature, and triangulated their findings. The conclusions of the experts individually revealed a convergence of thoughts, beliefs, and practices across. The study concluded that even though there isn’t much research done in Kenya on the same subject;what is available illustrates how crucial good communication is for patients with chronic illnesses. The study’s findings also highlighted the positive effects of effective communication between patients and healthcare professionals on treatment plan adherence, patient satisfaction, and overall health outcomes. The results also noted that in order to improve patient care and outcome, Kenyan healthcare workers should underscore developing their communication skills. The study also found that the incorporation of cybernetics is crucial if a truly  effective communication is required so as to enable centered care for patients with long-term diseases in Kenya. The goal of the Cybernetics is to activate genuinely effective communication in the care of Patients with long-term disease in Kenya. This study is organized to begin with an abstract, followed by keywords, an introduction, literature review, methodology, findings, discussion, and finally conclusions. 展开更多
关键词 A Preliminary Literature Review Meta-Analysis Indigenous Cancer Palliative Care Ontology EPISTEMOLOGY Phenomenological Approach effective Communication Chronic Illnesses Enhanced-Patient Care A Non-Probability Sampling A snow Ball Technique CYBERNETICS
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海洋中示踪物等值线的分形长度及其与混合效率的关系
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作者 钱钰坤 刘统亚 +1 位作者 张华 彭世球 《热带海洋学报》 CAS CSCD 北大核心 2024年第1期1-15,共15页
涡致混合扩散是物理海洋研究中的热点和难点问题。本文基于“有效扩散”理论,研究示踪物等值线在海表地转湍流的多尺度搅拌作用下,发生拉伸、扭曲、变形、折叠等改变其几何拓扑结构的现象,并探讨了等值线分形长度的变化与混合效率的关... 涡致混合扩散是物理海洋研究中的热点和难点问题。本文基于“有效扩散”理论,研究示踪物等值线在海表地转湍流的多尺度搅拌作用下,发生拉伸、扭曲、变形、折叠等改变其几何拓扑结构的现象,并探讨了等值线分形长度的变化与混合效率的关系。研究结果表明,在地转流场的搅拌下,示踪物的等值线会被迅速拉长,并产生丰富的精细结构。这种分形式的增长可达原长度的10~20倍,是混合效率提高的主要原因;而涡丝和锋面伴随的梯度增强虽然也有贡献,但为次要因素。另一方面,在示踪物模拟过程中,小尺度扩散会通过不可逆混合对示踪物进行均匀化,从而抹平等值线的精细结构,抑制等值线的增长,限制混合效率的提高。基于“数盒子”算法计算了等值线的分形维度,其数值在1.4到1.6之间,介于一维和二维之间。但由于地转湍流数据分辨率的限制,无法考虑更小尺度(次中尺度过程)的搅拌作用,可能低估了等值线的分形长度和混合效率。本研究将海洋混合与等值线几何特征联系了起来,初步得到了分形长度和混合效率两者的经验关系式,未来可以利用图像识别等成熟遥感技术将海洋示踪物等值线的几何特征直接转换为混合效率,为诊断分析海洋混合及其参数化提供了一种新的思路。 展开更多
关键词 海洋混合 地转湍流 分形几何 有效扩散 等值线
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相变沥青混合料融雪效果及评价指标研究
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作者 彭波 刘维 +2 位作者 苟国涛 吕雪颖 苏佑鹏 《中国科技论文》 CAS 2024年第4期407-413,442,共8页
为确定DTC相变材料(phase change material,PCM)在沥青路面中的融雪效果及评价指标,通过设计室内和室外融雪试验,以未掺加相变材料的沥青混合料试件作为对照组,研究并分析低温下相变沥青混合料的融雪效果。结果表明:相变材料在沥青混合... 为确定DTC相变材料(phase change material,PCM)在沥青路面中的融雪效果及评价指标,通过设计室内和室外融雪试验,以未掺加相变材料的沥青混合料试件作为对照组,研究并分析低温下相变沥青混合料的融雪效果。结果表明:相变材料在沥青混合料中具有明显的调温作用,掺量越大,融雪效果越明显;相变材料掺量为0.5%、积雪厚度分别为1.5 cm和3.0 cm时,与普通沥青混合料相比,相变沥青混合料融雪速率分别提高19.0%和16.0%。基于室内和室外融雪试验,提出以积雪厚度变化率(Δh)和余雪覆盖率(residual snow coverage,RSC)作为相变沥青混合料融雪效果的综合评价指标。 展开更多
关键词 相变沥青混合料 室内融雪试验 室外融雪试验 融雪效果 评价指标
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洋中脊动力学与俯冲带地震-岩浆-成矿事件远程效应
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作者 成秋明 《地学前缘》 EI CAS CSCD 北大核心 2024年第1期1-14,共14页
板块俯冲带和大陆岩浆弧的深部过程与极端地质事件之间存在密切的关系。板块俯冲与造山过程会导致地震、岩浆活动和成矿等事件的发生。这些极端事件的发生与俯冲过程中的壳幔相互作用、地幔楔形成、岩石圈部分熔融、构造-岩浆活动等因... 板块俯冲带和大陆岩浆弧的深部过程与极端地质事件之间存在密切的关系。板块俯冲与造山过程会导致地震、岩浆活动和成矿等事件的发生。这些极端事件的发生与俯冲过程中的壳幔相互作用、地幔楔形成、岩石圈部分熔融、构造-岩浆活动等因素密切相关。然而,人们对洋中脊新生地壳的不均匀性或先天“缺陷”对以上的极端事件的长远影响和远程效应了解甚少。在洋中脊新的地壳形成过程中,由于受到板块扩张、压力降低、软流圈物质上涌等因素的作用,导致新生地壳温度升高、孔隙度和裂缝发育、密度降低、结构复杂的正反馈过程。因此,新生地壳在密度、强度、温度、厚度等方面存在非均质性。这些地壳的差异性将影响和决定板块在扩张和俯冲过程中的行为,并对板块俯冲作用形成的地震、岩浆和成矿等事件产生远程影响。以太平洋俯冲和安第斯造山带为例研究发现,板块运动速度、板块俯冲角度、板片撕裂、岩石圈厚度、Moho面深度等的突变与地震、火山和斑岩矿床的时空分布存在远程关联效应,这些认知对预测板块俯冲-碰撞带发生的极端地质事件的时空分布具有重要意义。 展开更多
关键词 洋中脊 板块俯冲 地震 火山 成矿 远程关联
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典型水深与海底介质条件下的OBC/OBN多分量地震数据波型特征
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作者 王腾飞 刘学义 程玖兵 《石油物探》 CSCD 北大核心 2024年第1期45-60,共16页
海底电缆或海底节点(OBC/OBN)多分量地震是开展海上复杂油气藏勘探的重要手段之一。由于地震波与自由表面及海底界面的互相作用,海底多分量地震记录中波型成分十分复杂。调查其中各类信号与噪声的形成机制及其影响,可为后续数据处理与... 海底电缆或海底节点(OBC/OBN)多分量地震是开展海上复杂油气藏勘探的重要手段之一。由于地震波与自由表面及海底界面的互相作用,海底多分量地震记录中波型成分十分复杂。调查其中各类信号与噪声的形成机制及其影响,可为后续数据处理与解释提供关键依据。针对海底多分量地震观测条件下潜在的波场信号,按照不同水深与典型海底沉积物性质构建代表性的弹性参数模型,利用谱元法合成OBC/OBN多分量地震记录,分析各类波型成分的表现特征,揭示水深和海底介质特性对波场运动学及动力学特征的影响。通过与东海浅水区和南海深水区海底地震仪(OBS)采集的实际地震数据的对比分析,确认了水深与海底介质条件对表面多次波与海底界面波的调控机理,为海底多分量地震数据处理方法研究与技术应用提供有益的指导。 展开更多
关键词 海底多分量地震 海底界面效应 P-S模式耦合 自由表面多次波 海底地震仪 OBC/OBN
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特提斯洋与古亚洲洋协同演化控制下的塔里木台盆区油气富集效应
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作者 何治亮 杨鑫 +4 位作者 高键 云露 曹自成 李慧莉 杨佳奇 《石油与天然气地质》 EI CAS CSCD 北大核心 2024年第3期637-657,共21页
显生宙特提斯洋和古亚洲洋2大构造域演化历史对塔里木盆地产生了巨大的影响,其效应包括原型盆地的形成与沉积充填过程及油气成藏与调整改造等。原特提斯洋和古亚洲洋分别经历了扩张、俯冲-消减和关闭-碰撞造山过程。特提斯域经历了原特... 显生宙特提斯洋和古亚洲洋2大构造域演化历史对塔里木盆地产生了巨大的影响,其效应包括原型盆地的形成与沉积充填过程及油气成藏与调整改造等。原特提斯洋和古亚洲洋分别经历了扩张、俯冲-消减和关闭-碰撞造山过程。特提斯域经历了原特提斯、古特提斯和新特提斯3个阶段,具有此消彼长的关系。古亚洲洋在新元古代—古生代多陆-岛-洋的格架下经历了复杂的伸展—聚敛过程。受特提斯洋(昆仑-阿尔金分支洋)和古亚洲洋(南天山洋分支)协同演化控制,塔里木盆地经历了新元古代—早古生代和晚古生代—新生代2个从伸展—聚敛的巨型盆地旋回,与海平面升降和气候旋回匹配,形成了优质烃源岩、多类型规模性储层和盖层,构成了油气形成的优越物质基础。特提斯洋和古亚洲洋多圈层协同演化控制的油气富集效应体现在:①多类型盆地原型与后期构造改造决定了塔里木台盆区不同部位油气成藏与富集的差异性;②北部坳陷广泛分布的优质烃源岩,是塔北—顺托—塔中地区大型油气富集区形成的基础;③多期构造运动伴随的构造破裂与古岩溶作用造就了断控缝洞型和岩溶缝洞型2类各具特点且规模发育的储集体;④区内构造与地温场差异演化决定了油气聚集区内油气相态与次生改造的规律性变化。台盆区大型古隆起和不整合面、走滑断裂带、高能相带及其叠加区是油气有利目标区。 展开更多
关键词 富集效应 成藏要素 变形改造 盆地原型 构造演化 古亚洲洋 特提斯洋
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交互式VR-Ocean虚拟海洋环境与生命仿真平台的设计与实现 被引量:9
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作者 陈戈 李文庆 李小宁 《中国海洋大学学报(自然科学版)》 CAS CSCD 北大核心 2009年第5期1037-1041,共5页
从底层研究和构建一个虚拟海洋场景快速编辑平台。对平台的整体组成结构、工作流程和用户交互功能进行了设计,使用水面水下分开渲染、以方向确定路线的海洋生命路径规划以及水下刻蚀动态纹理叠加等关键技术和方法,基于VC++、OpenGL和GP... 从底层研究和构建一个虚拟海洋场景快速编辑平台。对平台的整体组成结构、工作流程和用户交互功能进行了设计,使用水面水下分开渲染、以方向确定路线的海洋生命路径规划以及水下刻蚀动态纹理叠加等关键技术和方法,基于VC++、OpenGL和GPU对海洋环境中海上、海面及海下各种可见要素进行3D虚拟,重点在海洋生命行为模拟、行为仿真和海洋特效动态展示。平台的运行满足实时性和交互性的各项要求。最后,还对VR-Ocean平台应用和技术拓展进行了论述和展望。 展开更多
关键词 虚拟现实 虚拟海洋环境 海洋生命仿真 海洋特效 VR-ocean平台
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海洋酸化对藻类生态学效应及作用机制的研究进展
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作者 刘雅静 席天乐 +1 位作者 梁成伟 叶乃好 《生态毒理学报》 CAS CSCD 北大核心 2024年第1期1-16,共16页
目前全球海洋酸化(ocean acidification,OA)问题正在以前所未有的速度快速恶化,使海洋生物以及海洋生态环境面临着巨大的威胁。藻类作为海洋中最主要的初级生产者,贡献了约95%的初级生产力,是物质循环和能量流动的重要环节。海洋酸化能... 目前全球海洋酸化(ocean acidification,OA)问题正在以前所未有的速度快速恶化,使海洋生物以及海洋生态环境面临着巨大的威胁。藻类作为海洋中最主要的初级生产者,贡献了约95%的初级生产力,是物质循环和能量流动的重要环节。海洋酸化能够改变藻类的初级生产力,从而影响海洋食物网中物质和能量从初级到次级生产者及更高营养级的传递,引发食物链效应,进而对整个海洋生态系统带来不可逆转的影响,因此评估海洋酸化对藻类的影响具有重要的生态学研究意义。本文总结了近年来海洋酸化对藻类的光合作用、碳固定、生长、钙化、繁殖等生理生化过程以及对代谢组分和显微结构的影响,归纳了海洋酸化对藻类的分子调控机制,同时围绕海洋酸化与环境因子以及海洋污染物对藻类的复合胁迫展开综述,并基于当前海洋酸化对藻类影响研究中存在的不足做出展望,以期为人们解决海洋酸化问题提供思路和方法。 展开更多
关键词 海洋酸化 藻类 生态学效应 作用机制
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远海环境低成本RTK接收机多路径效应与平滑伪距单点定位性能
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作者 彭凌智 燕兴元 +2 位作者 杨萌 冯伟 钟敏 《大地测量与地球动力学》 CSCD 北大核心 2024年第7期674-679,共6页
低成本RTK接收机抗多路径性能较弱,导致远海环境中的单点定位性能显著下降。综合分析远海环境中载波相位平滑抑径算法对低成本RTK接收机单点定位性能的影响。结果表明,远海环境中RTK接收机的多路径效应为陆地环境的2~3倍,E5频点的抗多... 低成本RTK接收机抗多路径性能较弱,导致远海环境中的单点定位性能显著下降。综合分析远海环境中载波相位平滑抑径算法对低成本RTK接收机单点定位性能的影响。结果表明,远海环境中RTK接收机的多路径效应为陆地环境的2~3倍,E5频点的抗多路径性能最强;平滑抑径效果与伪距多路径效应大小有关,采用平滑抑径算法后,RTK接收机SPP定位精度在远海环境提升62%,在陆地环境提升24%;平滑抑径后GPS/Galileo/BDS-3多系统SPP定位精度优于1 m,可满足海上较精细作业的需求。 展开更多
关键词 RTK接收机 伪距单点定位 远海环境 多路径效应 载波相位平滑伪距
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