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应用海洋学学报 2024年第1期43卷 192-200页

作者：李俊佳陈磊王君玥蔡月凤申欣姬南京江苏海洋大学、江苏省海洋生物资源与环境重点实验室、江苏省海洋生物技术重点实验室江苏连云港222005 江苏海洋大学、江苏省海洋生物产业技术协同创新中心江苏连云港222005 江苏省海洋资源开发研究院江苏连云港222005

近年来,有害藻华频繁发生给海洋生态系统甚至人类健康带来严重影响。伊姆裸甲藻(Gymnodinium impudicum)是一种典型有害藻华原因种,开展其溶藻菌筛选工作,将有利于该种藻华的防控研究。本研究从伊姆裸甲藻藻华发生海域,分离一株针对藻... 详细信息

近年来,有害藻华频繁发生给海洋生态系统甚至人类健康带来严重影响。伊姆裸甲藻(Gymnodinium impudicum)是一种典型有害藻华原因种,开展其溶藻菌筛选工作,将有利于该种藻华的防控研究。本研究从伊姆裸甲藻藻华发生海域,分离一株针对藻华原因种的溶藻菌LD-B3.16S rDNA序列分析表明,该菌株属于假交替单胞菌属(Pseudoalteromonas)。菌藻共培养结果显示,2.0%终浓度LD-B3.液添加72.h后,伊姆裸甲藻溶藻率达81.06%,且溶藻效应呈现浓度和时间依赖性。显微观察和生理参数测定结果表明,菌株LD-B3.导致伊姆裸甲藻细胞链断裂,最大光合效率(Fv/Fm)下降。溶藻方式研究发现,菌株LD-B3.要通过分泌胞外物质实现溶藻,且这类物质对温度较为敏感,初步推断其可能为蛋白类物质。本研究结果表明菌株LD-B3.伊姆裸甲藻溶藻剂开发方面有一定应用前景。

关键词：海洋生物学有害藻华伊姆裸甲藻溶藻菌假交替单胞菌

An Experiment to Explain Depth of Cut Notch Wear of Ceramic Tools in Ni- based Super-alloy Machining

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厦门大学学报（自然科学版） 2002年第S1期41卷 86-87页

作者： WANG Zhi-gang 1, HE Ning 2.(1. Dept. of Mechanical Engineering, National university of Singapore, Singapore 2. Dept. of Mechanical Engineering, nanjing university of Aero.& Astro , Nanj ing 2.0016, China)

Inconel 718, a high temperature alloy, is extensive ly used in aircraft, gas engines and nuclear-power plants. It is generally known that the life of ceramic cutting tools in machining Inconel 718 is often restric ted by depth-of-cut (DOC) notch wear. In view of the number of various factors involved and the variety of tool materi als and cutting conditions available, the analysis of the DOC notch wear is very difficult. According to previous work concerning the DOC notch wear of ceramics tools, some Al 2. 3.- and Si 3. 4 -based ceramics tools have show n that the degree of tool notching depends on the thermal shock resistance of a tool material and thermal gradients (interrupted cutting, use of flood coolants) . Other observations suggest that there are chemical interactions between the to ol material and the work-piece. At the same time, an analytical technique based on thermodynamic properties for estimating cutting tool wear was proposed. Howe ver, so far, there is no concrete and convincing explanation for the DOC notch w ear. In all previous studies on the DOC notch wear, it is often assumed that notch we ar happened in the contacting region of the cutting tool and the work-piece, wh ile the exact position of notch wear is always neglected. In his article, He Ning measured the distance l n between tool nose and the center of DOC notch wear, and calculated the theoretical working length l d ― the ideal distance between the DOC notch center and the intersection of th e theoretical depth of cut line and the cutting edge. He found that l n is always greater than l d. It means that the position of the DOC notch is not at the depth of cut line, but out of the theoretical cutting area. He supposed that the saw-tooth shaped burrs and fin-shaped chip edges cause the DOC no tch wear, because only the saw-tooth shaped burrs and fin-shaped chip edges ha ve effect on the tools at the region of notch wear. Although He described the reason of notch wear and did some theoreti

关键词： notch wear ceramic tool high speed machining

A virtual reference satellite differential method for relative correction of satellite ephemeris errors

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Science China(Physics,Mechanics & Astronomy) 2010年第12期53卷 2300-2306页

作者： CAI ChengLin 1,3., LI XiaoHui 2.3.& WU HaiTao 2.3.1 Gulin university of Electronic Technology, 541004, China 2.National Time Service center, Chinese Academy of Sciences, Lintong 710600, China 3.Key Laboratory of Precision Navigation and Timing Technology, National Time Service center, Chinese Academy of Sciences, Lintong 710600, China 1. Gulin university of Electronic Technology Gulin 541004 China3. Key Laboratory of Precision Navigation and Timing Technology National Time Service Center Chinese Academy of Sciences Lintong 710600 China2. National Time Service Center Chinese Academy of Sciences Lintong 710600 China

In order to solve the problems that the novel wide area differential method on the satellite clock and ephemeris relative correction (CERC) in the non-geostationary orbit satellite constellation, a virtual reference satellite (VRS) differential principle using relative correction of satellite ephemeris errors is proposed. It is referred to be as the VRS differential principle, and the elaboration is focused on the construction of pseudo-range errors of VRS. Through qualitative analysis, it can be found that the impact of the satellite’s clock and ephemeris errors on positioning can basically be removed and the users’ positioning errors are near zero. Through simulation analysis of the differential performance, it is verified that the differential method is universal in all kinds of satellite navigation systems with geostationary orbit (GEO) constellation, Medium orbit (MEO) constellation or hybrid orbit constellation, and it has insensitivity to abnormal aspects of a satellite ephemeris and clock. Moreover, the real time positioning accuracy of differential users can be maintained within several decimeters after the pseudo-range measurement noise is effectively weakened or eliminated.

关键词： wide area differential method virtual reference satellite (VRS) satellite ephemeris errors satellite clock errors constellation

The Mossbauer spectra and coordination structure of some dialkyltin (Ⅳ) derivatives

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Chinese Journal of Chemistry 1986年第1期4卷 29-34页

作者： WANG Xu-Kun LIU Xiang-Yang XIAO Lai WANG Yung-Tai YIAN Qi-Je XIA Yuan-Fu WANG Shu-Xin Institute of Elementoorganic Chemistry, Nankai university, Tianjin Department of Chemistry, Department of Physics, nanjing university, {2. The {3. of analysis and Test, Nankai university Computer {3. of {2. Institute of Posts and Telecommunications. Institute of Elementoorganic Chemistry Nankai University Tianjin Department of Chemistry Department of Physics Nanjing University Nanjing

Five new bis（β-carbomethoxyethyl）tin derivatives including R2.n（acac）2.R=CH3.COCH2.H2., R2.n（dbm）2. R2.nO, R'2.n（dbm）2.R'=CH3.COCH（CH3.CH2. and R'2.nOwere synthesized. The structures of these compounds were compared with R2.nCl2. R'2.nCl2.(C8H17)2.nCl2. and (C8H17)2.n(OCOC11H2.0}2.1H NMR, IR and Mossbauer spectroscopic datashowed that R'2.n（dbm）2.ontains a cis C-Sn-C unit, (C8H17)2.n(OCOC11H2.0}2.xists as a mixtureof two isomers, while the other compounds have a trans C-Sn-C unit.

关键词： OC derivatives The Mossbauer spectra and coordination structure of some dialkyltin

Screening for Y chromosome microdeletions in idiopathic and nonidiopathic infertile men with varicocele and cryptorchidism

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中华医学杂志(英文版) 2005年第17期000卷 56-61页

作者： SONG Ning-hong, WU Hong-fei, ZHANG Wei, ZHUO Zuo-min, QIAN Li-xing, HUA Li-xing, GUO Lin and FENG Ning-hanDepartment of Urology, First Affiliated Hospital, nanjing Medical university, nanjing 2.002., ChinaKey Laboratory of Reproductive Medicine of Jiangsu Province,nanjing Medical university, nanjing 2.002., ChinaModel Animal Research center, nanjing university, nanjing2.003., China Department of Urology First Affiliated Hospital Nanjing Medical University Nanjing 210029 China Key Laboratory of Reproductive Medicine of Jiangsu Province Nanjing Medical University Nanjing 210029 China Model Animal Research center Nanjing University Nanjing 210032 China

Background Cytogenetic and molecular studies of azoospermic and oligozoospermic males have suggested thepresence of azoospermia factors (AZF) in the Y *** in AZF regions has been reported todisrupt spermatogenesis and cause *** candidate genes responsible for spermatogenesis have beenidentified in this region and some of them are thought to be functional in human *** wereported clinical and molecular studies of Ychromosome microdeletions in *** study aimed atassessingthe frequency of microdeletions in Chinese men with idiopathic and nonidiopathic infertility problems anddicussing the clinical significance of the AZF *** In this study, we screened 143.infertile men (62.with idiopathic infertilitas and 81 withnonidiopathic infertilitas), in whom karyotype, sperm count, hormonal parameters and fine needle aspirationcytology were *** DNA was extracted from the peripheral *** analysis wasperformed by two multiplexpolymerase chain reactions (PCR) using a set of a sequence tagged sites (STS) from3.different regions of the Y chromosome: AZFa (sY84, sY86), AZFb (sY12., sY13.), AZFc (sY2.4,sY2.5).Results Nineteen point four percent of idiopathic males (12.62. 19.4%) had microdeletions of either theAZFa, AZFb, AZFc or AZFb +c ***, a high frequency of microdeletions (9/81, 11.1%) wasfound in nonidiopathic patients with varicocele and *** deletions were found in healthy *** were no significant differences in the localization and extent of deletions between idiopathic andnonidiopathic *** The knowledge of the presence of these deletions in idiopathic and nonidiopathic cases isimportant to understand the prognosis, better management and counsel these patients ***,a more extended screening for Y chromosome microdeletions in idiopathic and nonidiopathic men, particularlycandidates for intracytoplasmic sper

关键词： Y chromosome · microdeletions · multiplex polymerase chain reaction · male infertility

The application of geographic information technology to coastal geomorphology

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Acta Oceanologica Sinica 2009年第5期28卷 49-57页

作者： GUO Wei LI Shuheng ZHU Dakui School of Human Settlements and Civil Engineering Xi＇an Jiaotong University Xi＇an 710049 China Department of Computer Sciences Xi＇an Jiaotong University Xi＇an 710049 China Department of Urban and Resources Sciences Northwest University Xi＇an 710032 China Faculty of Environmental Sciences University of Waterloo Waterloo N2L3G1 Canada Key Laboratory of Coast ＆ Island Development of Ministry of Education Nanjing University Nanjing 210093 China

With the development of modern oceanic observation technologies, coastal survey data have been experiencing a substantial growth. The integration management of the data from different disciplines, different sources and different formats has become a major research field in coastal geomorphology by using Geographic Information System （GIS）. This paper puts forward a new methodology framework of GIS techniques in coastal ocean geomorphology, including data acquisition, process, analysis, and representation. It focuses on some major GIS techniques to study the land-ocean interaction mechanism, such as spatial analysis, submarine topography model and three-dimension （3.） visualization, and apply its result to coastal urban planning, harbor site selection and geomorphology environment about coral reef and islands on the continental shelf. The case studies cover the whole coastal ocean to serve the social community, economical development and diplomatic rights for decision-making all round in the coastal zone. The research shows clearly that the application of coastal multi-source geospatial platform has changed the traditional coastal geomorphology science dramatically from its research scope, fields and methods, however, as made clear in this paper, extracting accurate information from remote sensing data and GIS databases for coastal geomorphological applications is a nontrivial challenge that requires the combined knowledge and skills of information scientists and geomorphologists.

关键词： coastal geomorphology geographic information system (GIS) spatial analysis threedimensional visualization

Electric-stimulus rate encoding algorithm of Mandarin tonal information in cochlear implant

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Progress in Natural Science:Materials International 2006年第12期16卷 1315-1321页

作者： GUAN Tian~1, GONG Qin~1 and YE Datian~2.*(1. Department of Biomedical Engineering, Tsinghua university, Beijing 100084, China 2. Research center of Biomedical Engineering, Graduate School at Shenzhen, Tsinghua university, Shenzhen 518055, China) [a]Department of Biomedical Engineering Tsinghua University Beijing China [b]Research center of Biomedical Engineering Graduate School at Shenzhen Tsinghua University Shenzhen China

The modern multi-channel cochlear implants usually extract and encode the temporal envelope cues. This kind of algorithms can hardly satisfy the users who speak tonal languages, such as Mandarin. Many studies have tried to enhance the recognition ability of Mandarin through encoding tonal information and made suggestions to frequency-modulate the fixed pulse-rate carrier with the extracted tonal information based on the rate-pitch theory in electric hearing. However, how to encode and deliver the tonal information such as F_0by changing electric-stimulus rate has not got further study in clinical electric-stimulus mode. The present paper focuses on this matter by piecewise calculating the appreciable electric-stimulus rates. Then an electric-stimulus encoding algorithm of Mandarin tone is brought forward and testified through acoustic simulations. Such conclusion can be drawn that this algorithm of electric-stimulus rate could convey tonal information well and help to enhance the Mandarin speech recognition ability.

关键词： cochlear implant tone fundamental frequency electric-stimulus rate.

Teleconnection between the Indian summer monsoon onset and the Meiyu over the Yangtze River Valley

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Science China Earth Sciences 2008年第7期51卷 1021-1035页

作者： LIU YunYun1,2.3.& DING YiHui2.1 Chinese Academy of Meteorological Sciences, Beijing 100081, China 2.National Climate center, Beijing 100081, China 3.Graduate university of Chinese Academy of Sciences, Beijing 100049, China 1. Chinese Academy of Meteorological Sciences Beijing 100081 China 2. National Climate center Beijing 100081 China 3. Graduate university of Chinese Academy of Sciences Beijing 100049 China

Based on the Indian and Chinese precipitation data and the NCEP-NCAR reanalysis circulation data, the relationship between the Indian summer monsoon (ISM) onset and the Meiyu over the Yangtze River Valley has been discussed by the methods of correlation analysis and composite analysis. The results show that the date of ISM onset over Kerala in the southwestern coast of the Indian Peninsula is about two weeks earlier than the beginning of the Meiyu over the Yangtze River Valley. After the outbreak of ISM, the teleconnection mode sets up from the western coast of India via the Bay of Bengal (BOB) to the Yangtze River Valley and southern Japan. It is different both in time and space from the telecon- nection mode which is from the northwest of India via the Tibetan Plateau to northern China. The for- mer mode is defined as the "south" teleconnection of the Asian summer monsoon, forming in the pe- riod of ISM onset; while the latter mode is called the "north" teleconnection, mainly occurring in the Asian monsoon culminant period. During the process of the "south" teleconnection’s formation, the Asian monsoon circulation has experienced a series of important changes: ISM onset, the northward movement of the south Asia high (SAH), the onset vortex occurrence, the eastward extension of the stronger tropical westerly belt, and the northeastward jump of the western Pacific subtropical high (WPSH), etc. Consequently, since ISM sets up over Kerala, the whole Asian continent is covered by the upper SAH after about two weeks, while in the mid- and lower troposphere, a strong wind belt forms from the Arabian Sea via the southern India, BOB and the South China Sea (SCS), then along the western flank of WPSH, to the Yangtze River Valley and southern Japan. With the northward moving of the subtropical jet streams, the upper westerly jet stream and the low level jet have been coupled ver- tically over east Asia, while the Yangtze River Valley happens to locate in the ascending motion

关键词： Indian summer monsoon (ISM) the Meiyu over the Yangtze River Valley teleconnection mode

Hydrothermal Treatment of Sol-Gel TiO2.Film

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稀有金属材料与工程 2006年第S3期 570-571页

作者： Shaohua Zhang~1 Bing Xie~2.Fengyi Li~3.Tude Zou~2.(1.School of Materials,Nanchang university,Jiangxi 3.0047,China) (2.center of {2. and Test,Nanchang university,Jiangxi 3.0047,China) (3.School of Science,Nanchang university,Jiangxi 3.0047,China)

The preparation of TiO2.ilm has been an important research *** our work,we obtained the TiO2.ilm by hydrothermal treating the amorphous film prepared by sol-gel method or the hydrolysis of titanium *** influence of temperature and duration time on the film properties was *** photo degradation of methyl orange in aqueous solution of the film was *** films were characterized by XRD and Uv-Vis spectroscope.

关键词： titania film hydrothermal sol-gel