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Paleoenvironmental implications of Holocene long-chain n-alkanes on the northern Bering Sea Slope

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Acta Oceanologica Sinica 2017年第8期36卷 137-145页

作者： ZHANG Haifeng wang Rujian XIAO wenshen Laboratory of Marine Ecosystem and Biogeochemistry State Oceanic Administration State Key Laboratory of Marine Geology Tongji University

The records of high-resolution terrestrial biological markers （biomarkers） from Core B2-9 from the northern Bering Sea Slope over the last 9.6 ka BP were presented in the study. Variations in input of terrestrial long-chain n-alkanes （referred to as n-alkanes） and vegetation structure in their source regions were investigated. The results show that the nCz7 is the main carbon peak and has the greatest contribution rate of the total n-alkane content; this might be related to the abundance of woody plants and their spatial distribution in the source region, nC23 is another n-alkane having a relatively high content; this was mainly derived from submerged plants widespread along the coastal areas in the northern hemisphere. Total n-alkane content dropped quickly at ca. 7.8 ka BP, ca. 6.7 ka BP and ca. 5.4 ka BP, and was followed by four relatively stable stages mostly controlled by sea-level rise, climate change and vegetation distribution in the source region. Variation in carbon preference index （CPI） indicates that the n-alkanes primarily originated from higher land plants, and the average chain length （ACL） and nCa1/nC27 ratio reveal the relatively stable presence of woody/herbaceous plants during the Holocene, and dominate woody plants in most of the time. Simultaneous variation in total n-alkane content, nC27 content and its contribution, CPI, ACL and nC31/nC27 ratio over several short periods suggest that the growth rate of the woody plant n-alkane contribution was lower than that of herbaceous plants and fossil n-alkanes under the particular climatic conditions of the source region.

关键词： Bering Sea terrestrial input long-chain n-alkanes vegetation structure Holocene

Genetic background effects on introgression,QTL expression and cryptic genomic variation due to subspecific differentiation in rice

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Genetic background effects on introgression,QTL expression a...

2010中国作物学会学术年会

作者： Yun wang~(1,2),Lirui Cheng~1,Yong Sun~1,wenshen wang~1,Rongshen Guan~1,Linghua Zhu~1, Zhikang Li~(1,3) (1 Institute of Crop Science,Chinese Academy of Agricultural Sciences,Beijing 100081,China 2Shenyang Agricultural University,Shenyang 110161,China 3International Rice Research Institute,DAPO Box7777,Manila,Philippines.

Two large sets of reciprocal introgression lines(ILs) derived a japonica variety ’Lemont’ and indica variety ’Teqing’,were analyzed using molecular markers to understand the transmission pattern of donor segments in reciprocal indica/japonica recipients of rice and the effects of genetic background on QTL expression of flag leaf width(LW) and spikelet number per panicle(SNP) under the two diverse environments (Beijing and Hainan).Comparison of the linkage maps from the two ILs and RIL populations from the same cross revealed a high frequency and genomewide distribution of inverted marker orders,suggesting the

关键词： genetic background effect intrasubspecific cryptic genomic variation subspecific differentiation genetic load Oryza sativa L.

来源： cnki会议评论

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重整催化剂活性评价的实验研究

炼油与化工 2009年第4期20卷 16-18页

作者：赵风知丁冉峰冉国朋王文生四川大学化学工程学院成都610065 北京金伟晖工程技术有限公司北京100083

利用北京金伟晖工程技术有限公司的重整催化剂评价装置,对自制的连续重整催化剂GGB—01进行了活性评价研究。考察了不同反应温度、反应压力及氢油比对重整转化率、液体收率、生成油辛烷值、氢产率的影响规律。结果表明:在反应温度430～... 详细信息

利用北京金伟晖工程技术有限公司的重整催化剂评价装置,对自制的连续重整催化剂GGB—01进行了活性评价研究。考察了不同反应温度、反应压力及氢油比对重整转化率、液体收率、生成油辛烷值、氢产率的影响规律。结果表明:在反应温度430～490℃内,生成油的辛烷值随温度的升高而逐渐提高。GGB—01重整规律明显,低压状态的反应效果优于高压状态。

关键词：重整催化剂活性评价转化率辛烷值

Late Quaternary ice-rafted detritus events in the Chukchi Basin, western Arctic Ocean

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Chinese Science Bulletin 2010年第4期55卷 432-440页

作者： wang RuJian XIAO wenshen LI WenBao SUN YeChen State Key Laboratory of Marine Geology Tong/i University Shanghai 200092 China Alfred Wegener Institute for Polar and Marine Research Bremerhaven 2 7517 Germany

The late Quaternary ice rafted detritus (IRD) events in the Chukchi Basin, western Arctic Ocean are indications of the provenance of the coarser detritus and ice export events, and also document the evolutionary histories of Beaufort Gyre and the North American Ice Sheet (NAIS). The sediment of core M03 from the Chukchi Basin was selected to study the regional response to the ice export events and the NAIS variability. The stratigraphic framework of M03 was established by a combination of lithological features and downcore color change cycles, AMS14C dating with foraminifera abundance and IRD events. The core was also compared with the adjacent core NWR 5 from the Northwind Ridge area. The core extends back to Marine Isotope Stage (MIS) 7. A sedimentary hiatus of 10―20 ka might occur between 16 to 20 cm core depth. Seven IRD events are distinguished from the studied core and are presented during the early MIS 1, MIS 3, MIS 5 and late MIS 7. These IRD are transported by sea ice and icebergs, which were exported to the Beaufort Sea from the M'Clure Strait Ice Stream, Canadian Arctic Archipelago, and brought to the Chukchi Basin by the Beaufort Gyre.

关键词：盆地沉积物晚第四纪北冰洋粗碎屑事件西部管理信息系统 MIS系统

Paleoceanographic records and sea ice extension history on the slope of the northern Bering Sea over the last 100 ka B.P.

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Acta Oceanologica Sinica 2005年第6期24卷 117-126页

作者： wang Rujian LI Xia XIAO wenshen XIA Peifen CHEN Ronghua State Key Laboratory of Marine Geology Tongji University Shanghai 200092China State Key Laboratory of Marine Geology Tongji University Shanghai 200092China State Key Laboratory of Marine Geology Tongji University Shanghai 200092China State Key Laboratory of Marine Geology Tongji University Shanghai 200092China Key Laboratory of Submarine Geoscience State Oceanic Administration Hangzhou 310012China

Quantitative analytic results of the biogenic components in Core B2-9 fromthe northern Bering Sea slope indicate that the coarse fraction and opal content, serving as proxiesof surface productivity, have increased stepwise since the marine isotope stageCMISJS.S, reflectingperiodic enhancement in surface *** surface productivity attained its highest levelduring the Holocene, followed by MIS 3.2 to 2 and then MIS 5.3 to 3.3 with a lowest level. Hightotal organic carbon(TOC) contents, together with high C/N ratios, which stand mostly between 7 and20, show that the TOC was deposited from mixing sources. Therefore,one has to be cautious to use TOCas a proxy of surface *** high TOC and C/N ratio during MIS 5.1, 3.3 to 3.2 and theHolocene reflect that the terrigenous organic matter input increased during *** in the fine- and silt-grained terrigenous components from MIS 5.3 to the middleHolocene imply that with the cooling climate, sea ice on the Bering Sea slope extended ***-rafted and charcoal detritus increased during glacial, interstadial and the last deglaciationperiods and decreased during interglacial periods, suggesting that sea ice on the slope increasedand melted, respectively, during glacial and interglacial periods. The extension of sea ice duringglacial *** was linked with the climate over the North American Continent, responded toglobal climate change during late Quaternary glacial and interglacial cycles.

关键词： surface productivity ice-rafted detritus sea ice extension history latequaternary bering sea

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基于模糊PID算法的MPD仿真控制研究

石油机械 2017年第6期45卷 36-39页

作者：王文深张淼淼卢怡李光耀刘伟河南省地质矿产勘查开发局第四地质矿产调查院巴音郭楞职业技术学院中国石油塔里木油田公司

为了解决反馈层抗干扰能力差和响应时间长的问题,建立了由反馈控制层、监测控制层和优化控制层构成的MPD 3级井底压力自动化控制架构,并且在反馈控制层首次引入模糊PID控制。利用MATLAB/Simulink对国外某井进行MPD多级控制仿真模拟,模... 详细信息

为了解决反馈层抗干扰能力差和响应时间长的问题,建立了由反馈控制层、监测控制层和优化控制层构成的MPD 3级井底压力自动化控制架构,并且在反馈控制层首次引入模糊PID控制。利用MATLAB/Simulink对国外某井进行MPD多级控制仿真模拟,模拟结果表明:模糊PID控制不仅使MPD缩短了控制时间,增强了抗干扰性,同时还引入人为经验的智能推理,使MPD控制更具人性化;在正常钻进过程中,系统对井底压力和钻井泵流量的变化反应迅速,通过调整节流阀开度可使井底压力始终处于安全压力窗口之内;在起下钻过程中,系统自动开启回压泵,钻井泵逐渐停止,通过调节节流压差可弥补摩阻压力。研究结果对于控压钻井技术的现场应用具有一定的参考作用。

关键词：控压钻井多级控制模糊PID控制模拟仿真

Paleoceanographic records in the Chukchi Basin, western Arctic Ocean during the late Quaternary

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Acta Oceanologica Sinica 2012年第1期31卷 83-94页

作者： wang Rujian XIAO wenshen SHAO Lei CHEN Jianfang GAO Aiguo State Key Laboratory of Marine Geology Tongji UniversityShanghai 200092China Second Institute of Oceanography State Oceanic AdministrationHangzhou 310012China Department of Oceanography Xiamen UniversityXiamen 361005China

The late Quaternary paleoceanographic changes in the western Arctic Ocean are revealed by quan- titative studies of foraminiferal abundance, ice-rafted detritus （IRD） and its mineralogical and petrological compositions, planktonic Neogloboquadrina pachyderma （sin.）（Nps）-δ18O and -δ13C, biogenic and non-biogenic components in Core M03 token from the Chukchi Basin during the Sec- ond Chinese National Arctic Expedition cruise. Seven IRD events appeared at MIS 7, 5, 3 and 1. These IRD were carried in massive icebergs, which were exported to the Beaufort Sea through the M＇Clure Strait Ice Stream, Canadian Arctic Archipelago, and then transported into the Chukchi Basin by the Beaufort Gyre. Low IRD deposition occurred during the glacial times when more extended ice cover and weakened Beaufort Gyre, while the open water condition and the intensified Beaufort Gyre during interglacial periods favored the IRD deposition. Therefore, the IRD events not only indicate the provenance of coarser detritus and ice export events, but also reflect the evolutionary histories of the Beaufort Gyre and North American ice sheet. Seven light Nps-δ18O and -δ13C excursions could respond to enhanced rates of sea ice formation resulting in the pro- duction and sinking of isotopically light brines, but was irrelevant to the warm Atlantic water and freshwater inputs. Whereas, the heavy Nps-δ18O and -δ13C values separately reflect the lessened Arctic freshwater and Pacific water, and well-ventilated surface water from the continental shelf and halocline water. Variations of CaCO3 content and planktonic foraminiferal abundance during the interglacial and glacial periods can demonstrate the incremental or diminishing input of the Atlantic water, while the total organic carbon （TOC） and opal contents increased and decreased during the glacial and interglacial periods, respectively, which could be related to the TOC degradation, opal dissolution and redox conditions of interface between the bottom wat

关键词： IRD events ice sheet light Nps-δ18O and -δ13C excursions surface productivity late Quaternary Arctic Ocean Chukchi Basin

Weighted spectral correlation angle target detection method for land‑based hyperspectral imaging

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Frontiers of Optoelectronics 2023年第4期16卷 121-134页

作者： Qianghui wang Bing Zhou wenshen Hua Jiaju Ying Xun Liu Yue Cheng Army Engineering University of PLA Shijiazhuang 050000China Army Engineering University of PLA Nanjing 210000China

In land-based spectral imaging,the spectra of ground objects are inevitably afected by the imaging conditions(weather conditions,atmospheric conditions,light conditions,zenith and azimuth angle conditions)and spatial distribution of targets,leading to uncertainties featured by“same object diferent spectrum”.That is,the spectrum of a ground object may change within a certain range under diferent imaging *** target detection(TD)methods are mainly based on similarity measurements and do not fully account for the spectral *** detection methods are prone to false detections or missed ***,reducing the impact of spectral uncertainties on TD is an important research topic in hyperspectral *** this paper,we frst review traditional TD methods and compare their principles and *** is found that the spectral correlation angle(SCA)method has good adaptability in land-based *** shortcoming of the SCA method that it cannot refect the local spectrum characteristics,is also *** the efect of spectral uncertainties cannot be completely overcome by the SCA method,a new similarity measurement method,the weighted spectral correlation angle(WSCA)method,is *** can reduce the infuence of spectral uncertainties on TD by increasing the weight of particular ***,we use two sets of experiments to analyze the efect of the WSCA method on *** performance in overcoming spectral uncertainties caused by variations in imaging conditions or uneven spatial distributions of targets is *** results show that the WSCA method can efectively reduce the infuence of spectral uncertainties and obtain a good detection result.

关键词： Hyperspectral image Spectral uncertain feature Target detection Land-based imaging condition Weighted spectral correlation angle(WSCA)

Removal of Nitrogen Compounds from Fuels by Deep Eutectic Solvent Based on 1-Butyl-3-Methylimidazolium Bromide and Dicarboxylic Acids

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China Petroleum Processing & Petrochemical Technology 2024年第3期26卷 93-101页

作者： Li wenshen Liu Jie School of Petrochemical Engineering Liaoning Petrochemical UniversityFushun 113001China

1-Butyl-3-methylimidazolium bromide-based ([Bmim]Br-based) deep eutectic solvents (DESs) can be used aseffective extractants for removing nitrogen compounds from fuel oil. Among the DESs studied, the combination of [Bmim]Brand malonic acid (MA) in a 1:1 molar ratio demonstrated good performance for the removal of both basic and non-basic Ncompounds. The DES [Bmim]Br-MA exhibited extraction efficiencies of 98.4% for quinoline and 92.9% for indole after 30min at 30 ℃ with a DES/oil mass ratio of 1/7. Moreover, the extraction efficiencies remained high at 86.4% for quinolineand 85.9% for indole after recycling the DES four times.. In addition, the DES [Bmim]Br-MA could effectively removeN compounds from Fushun shale diesel oil, with extraction efficiencies of 83.5% for total nitrogen and 89.9% for basicnitrogen at a DES/oil mass ratio of 1/1.

关键词： [Bmim]Br-based DES denitrogenation quinoline indole diesel oil