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Observations of marine snow and fecal pellets in a sediment trap mooring in the northern South China Sea

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Acta Oceanologica Sinica 2020年第3期39卷 141-147页

作者： Meng Gao Baoqi Huang zhifei Liu Yulong zhao Yanwei Zhang School of Earth and Space Sciences Peking UniversityBeijing 100871China State Key Laboratory of Marine Geology Tongji UniversityShanghai 200092China

Sediment traps are an important tool for studying the source, composition and sedimentation processes of sinking particulate matter in the ocean. An in situ observational mooring(TJ-A-1) is located in the northern South China Sea(20.05°N, 117.42°E) at a water depth of 2 100 m and equipped with two sediment traps deployed at 500 m and 1 950 m. Samples were collected at 18-day intervals, and 20 samples were obtained at both depths from May 2014 to May 2015. Large amounts of fecal matter and marine snow were collected in the lower trap. The fluxes of marine snow and fecal pellets exhibited a fluctuating decrease between May 2014 and early August 2014 and then stabilized at a relatively low level. Scanning electron microscopy observations revealed that the main components of the marine snow and fecal pellets were diatoms, coccolithophores, radiolarians, and other debris, all of which are planktons mostly produced in photic zone. Used in conjunction with the particle collection range estimates from the lower trap and data on ocean surface chlorophyll, these marine snow and fecal pellets were related to the lateral transport of deep water and not vertical migrations from overlying water column. Moreover, the source area might be southwest of Taiwan.

关键词： northern South China Sea sediment trap marine snow fecal pellets

肺癌精确放疗国产和进口设备的临床剂量学比较研究撤稿

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中国医疗设备 2021年第4期36卷 169-172页

作者：冀天楠安仙赵志飞中国人民解放军总医院第一医学中心放射治疗科

目的比较国产和进口加速器治疗肺癌在剂量学、均匀性指数（Homogeneity Index,HI）、适形度指数（Conformity Index,CI）方面的差异。方法从我院（A组=进口加速器+计划系统）既往肺癌患者随机选取20例,传输至148医院（B组=国产加速器+... 详细信息

目的比较国产和进口加速器治疗肺癌在剂量学、均匀性指数（Homogeneity Index,HI）、适形度指数（Conformity Index,CI）方面的差异。方法从我院（A组=进口加速器+计划系统）既往肺癌患者随机选取20例,传输至148医院（B组=国产加速器+进口计划系统）、404医院（C组=国产加速器+计划系统）进行计划设计和验证并比较结果,三组处方剂量和限值一致。剂量验证使用Gamma方法分析,比较3组剂量验证危及器官、肿瘤靶区（Plangross Tumor Volume,pGTV）和计划靶区（Planning Target Volume,PTV）的受量及HI和CI。采用配对样本t检验分析。结果 Gamma分析3 mm/3%,4 mm/4%通过率均在90%以上。评价肺及心脏、脊髓的剂量均值,结果显示C组最低;比较PTV的各项数据,C组所得的值较大,A、B两组差异不大,B组在HI和CI方面表现最好;比较pGTV各项指标,均无统计学意义。结论国产与进口精确放疗设备在Gamma通过率及剂量学各项指标上差异不大,仅在验证危及器官受量及PTV剂量时部分结果存在差异。

关键词：肺癌放射治疗国产加速器靶区剂量

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无线充电运输平台节能技术研究

黑龙江工程学院学报 2021年第4期35卷 24-28页

作者：陈冠楠崔宏耀赵智飞杨磊光陶莉炜黑龙江工程学院汽车与交通工程学院哈尔滨150050

以自行设计车模结构、无线充电智能寻迹的节能智能车为对象,通过快速成型技术打印车模结构、设计无线充电接收电路以及电磁运算放大电路等硬件电路的方法,基于S9KEAZ128ZAMLK系统,设计以超级电容为电源的智能寻迹小车。该小车能够实现... 详细信息

以自行设计车模结构、无线充电智能寻迹的节能智能车为对象,通过快速成型技术打印车模结构、设计无线充电接收电路以及电磁运算放大电路等硬件电路的方法,基于S9KEAZ128ZAMLK系统,设计以超级电容为电源的智能寻迹小车。该小车能够实现无线充电自启动、自动寻迹、自动避障、自动停车的功能。

关键词：无线充电节能 S9KEAZ128ZAMLK系统智能寻迹超级电容

快速康复外科理念在单孔胸腔镜肺叶切除术患者围手术期护理中的应用效果

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中华肺部疾病杂志（电子版） 2017年第4期10卷 457-460页

作者：赵志菲高苗莉陶莎赵宝琴董红雪王振华中国人民解放军海军总医院胸外科北京100048

目的探讨单孔胸腔镜肺叶切除患者围术期应用快速康复外科理念对其临床效果的影响。方法将124例单孔胸腔镜肺叶切除术治疗的患者随机分为观察组(FTS)和对照组,各62例;对照组围术期采用常规护理,观察组(FTS)采取快速康复外科护理措施,记... 详细信息

目的探讨单孔胸腔镜肺叶切除患者围术期应用快速康复外科理念对其临床效果的影响。方法将124例单孔胸腔镜肺叶切除术治疗的患者随机分为观察组(FTS)和对照组,各62例;对照组围术期采用常规护理,观察组(FTS)采取快速康复外科护理措施,记录并比较两组胸腔闭式引流管带管时间、肠鸣音恢复时间及住院时间;术后4、12、24、48 h时间节点的疼痛(VAS)程度;比较术后第2天和第5天的静息SaO_2。结果观察组胸腔闭式引流管带管时间、肠鸣音恢复时间及住院时间少于对照组(P0.05)。结论快速康复外科理念用于单孔胸腔镜肺叶切除术具有良好的临床效果,可以加快患者术后恢复、减轻术后疼痛、缩短住院时间,值得临床推广应用。

关键词：快速康复外科单孔胸腔镜肺叶切术护理,围术期

Pitfalls of acid leaching method for determining organic and inorganic carbon contents in marine sediments

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Acta Oceanologica Sinica 2020年第8期39卷 96-102页

作者： Chen Ling zhifei Liu Jingwen Zhang Yulong zhao Yanwei Zhang Adrian RFernandez State Key Laboratory of Marine Geology Tongji UniversityShanghai 200092China

Organic and inorganic carbon contents of marine sediments are important to reconstruct marine productivity,global carbon cycle, and climate change. A proper method to separate and determine organic and inorganic carbons is thus of great necessity. Although the best method is still disputable, the acid leaching method is widely used in many laboratories because of its ease-of-use and high accuracy. The results of the elemental analysis of sediment trap samples reveal that organic and inorganic carbon contents cannot be obtained using the acid leaching method, causing an infinitely amplified error when the carbon content of the decarbonated sample is 12%±1% according to a mathematical derivation. Acid fumigation and gasometric methods are used for comparison, which indicates that other methods can avoid this problem in organic carbon analysis. For the first time, this study uncovers the pitfalls of the acid leaching method, which limits the implication in practical laboratory measurement, and recommends alternative solutions of organic/inorganic carbon determination in marine sediments.

关键词： marine sediments organic carbon inorganic carbon acid leaching method limitation

Chemical weathering in Malay Peninsula and North Borneo:Clay mineralogy and element geochemistry of river surface sediments

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Science China Earth Sciences 2011年第2期54卷 272-282页

作者： WANG Hao LIU zhifei Edlic SATHIAMURTHY Christophe COLIN LI JianRu zhao YuLong State Key Laboratory of Marine Geology Tongji University Shanghai 200092 China Institute of Oceanography University Malaysia Terengganu Kuala Terengganu 21030 Malaysia Laboratoire IDES Bat. 504 UMR 8148 CNRS Universite de Paris XI Orsay 91405 France

Weathering products of silicate rocks are particularly useful for evaluating the continental chemical weathering on the Earth's surface and its *** mineralogy and major-element geochemistry of surface sediment samples collected in major rivers of Malay Peninsula and North Borneo in the tropical Southeast Asian region are used to study the present chemical weathering process and its controlling factors of tropical *** results indicate that the clay mineral assemblage in Malay Peninsula consists dominantly of kaolinite(average 80%) and minor illite(average 17%),almost without chlorite and smectite,whereas in North Borneo it consists mainly of illite and chlorite,with minor amounts of kaolinite(average 14%) and no *** contents of illite and chlorite in both Northwest and Northeast Borneo are 84% and 87%,***-element geochemical results of both bulk and clay-fraction sediments show intensive chemical weathering degree for both ***,the chemical weathering degree is gradually strengthened from Northeast Borneo,Northwest Borneo,to Malay Peninsula,and it is extremely intensive in Malay *** results indicate that,in the tropical Southeast Asian region exampled by Malay Peninsula and Borneo,climatic condition of tropical warm temperature and East Asian monsoon rainfall is the first-order controlling factor on the chemical weathering,resulting in intensive chemical weathering throughout tropical areas,and tectonic activity and lithology of parent rocks are subordinate factors,which still have an important impact on the weathering products,forming completely different clay mineral assemblages between Malay Peninsula and Borneo.

关键词： clay minerals major elements fluvial sediments chemical weathering Malay Peninsula Borneo

Effect of Lightweight Aggregates Incorporation on the Mechanical Properties and Shrinkage Compensation of a Cement-Ground Granulated Blast Furnace Slag-Phosphogypsum Ternary System

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Fluid Dynamics & Materials Processing 2024年第8期20卷 1773-1784页

作者： Yu Wang Mengyang Ma Yong Long Qingxiang zhao zhifei Cheng State Key Laboratory of Bridge Intelligent and Green Construction China Railway Major Bridge Engineering Group Co.Ltd.Wuhan430034China China Railway Bridge Science Research Institute. Ltd.Wuhan430034China

Shrinkage-induced cracking is a common issue in concrete structures,where the formation of cracks not only affects the aesthetic appearance of concrete but also potentially reduces its durability and *** this study,the effect of ceramsite sand addition on the properties of a ternary system of cement-ground granulated blast furnace slag(GGBFS)-phosphogypsum(PG)is *** particular,the fluidity,rheology,hydration heat,compressive strength,autogenous shrinkage,and drying shrinkage of the considered mortar specimens are *** results indicate that an increase in PG content leads to a decrease in fluidity,higher viscosity,lower exothermic peak,and lower compressive ***,the shrinkage of the mortar specimens is effectively *** incorporation of internal curing water from ceramsite sand improves fluidity,decreases both yield stress and viscosity,enhances the degree of hydration,and induces mortar ***,the inferior mechanical properties of the ceramsite sand generally produce a decrease in the compressive strength.

关键词： Phosphogypsum ceramsite sand internal curing mechanical property shrinkage

Turbidite deposition in the southern South China Sea during the last glacial: Evidence from grain-size and major elements records

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Chinese Science Bulletin 2011年第33期56卷 3558-3565页

作者： zhao YuLong LIU zhifei COLIN Christophe XIE Xin WU Qiong State Key Laboratory of Marine Geology Tongji University Shanghai 200092 China Laboratoire des Interactions et Dynamique des Environnements de Surface （IDES） UMR 8148 CNRS-Universite Paris-Sud I 1 Orsay 91405 France

High-resolution grain size and major element geochemical measurements were performed on the marine sediments of Core MD05-2895 to help understand the formation of turbidite sequences. Grain-size results show that these turbidite sediments contain more coarse sediment grains than normal marls. The coarse sediment grains are mostly derived from relict sediments on the Sunda Shelf. Relict sediments are composed mainly of quartz, feldspar, tephra and a few titaniferous or ferruginous heavy minerals. Corresponding to the concentration of these minerals, increases in Si/Al, K/Al, Ti/Al and Fe/Al ratios are observed in the turbidite layers. As all the observed turbidite sequences were deposited during the last glacial, the occurrence of these turbidity events is implied to be closely related to instabilities in sea-level-induced sediment supply. We suggest that deposition of sediment particles from a single turbidity current is usually controlled by a counterbalance between gravity and buoyancy, with the interaction of individual grains being of minor importance.

关键词：浊流沉积末次冰期南海南部粒度海洋沉积物证据中国地球化学测量

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全谱直读等离子体发射光谱法测定土壤中的硼

资源环境与工程 2012年第6期26卷 638-640页

作者：赵志飞陈芝桂唐兴敏彭望黄刚方金东湖北省地质实验研究所湖北武汉430034

研究全谱直读等离子体发射光谱测定土壤样品中的硼,对比样品的前处理条件,确定方便、快捷有效的样品分解办法;考察分析谱线干扰,选择最佳分析谱线。用土壤国家一级标准物质对分析方法准确度进行检验,结果准确可靠,满足规范要求,分析方... 详细信息

研究全谱直读等离子体发射光谱测定土壤样品中的硼,对比样品的前处理条件,确定方便、快捷有效的样品分解办法;考察分析谱线干扰,选择最佳分析谱线。用土壤国家一级标准物质对分析方法准确度进行检验,结果准确可靠,满足规范要求,分析方法精密度(RSD)为3.1%,分析方法检出限达到0.8μg/g,可运用于多目标区域地球化学样品中硼的准确测定。

关键词：土壤硼 ICP-OES