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Journal of Hydrodynamics 2011年第2期23卷 224-233页

作者： WANG Zhong LU Xiao-ping College of Naval Architecture and Power Naval University of Engineering Wuhan 430033 China

Up to now, there are no satisfactory numerical methods for simulating wave resistance of trimarans, mainly due to the difficulty related with the strong nonlinear features of the piece hull wave making and their interference. This article proposes a numerical method for quick and effective calculation of wave resistance of trimarans to be used in engineering applications. Based on Wyatt＇s work, the nonlinear free surface boundary condition, the time domain concept, and the full nonlinear wave making theory, using the Rankine source Green function, the 3-D surface panel method is expanded to solve the trimaran wave making problems, with high order nonlinear factors being taken into account, such as the influence of the sinking and trim, transom, and ship wave immersed hull surface. And the software is successfully developed to implement the method, which is validated. Several trimaran models, including a practical trimaran with a sonar dome and the transom, are used as numerical calculation samples, their wave making resistance is calculated both by the present method and some other methods such as linear （Dawson） methods. Moreover, sample model resistance tests were carried out to provide data for comparison, validation and analysis. Through the validation by model experiments, it is concluded that present method can well predict the wave making resistance, sinking and trim, and the accuracy of wave making resistance calculation is significantly improved by taking the trim and sinking into account, especially at high speeds.

关键词： trimaran nonlinear wave making resistance surface panel method sinking trim ship model test

Organic geochemical studies of sinking particulate material in China sea area Ⅱ——Geochemical significance of compositional features of ketone, aldehyde and alcohol compounds

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Chinese Science Bulletin 1997年第22期42卷 1894-1898页

作者： DUAN Yi,CUl Mingzhong, MA Lanhua, SONG Jinming, ZHOU Shixin and LUO Binjie1. Lanzhou Institute of Geology, Chinese Academy of Sciences, Lanzhou 730000, China 2. Earthquake Research Institute of Lanzhou, SSB, Lanzhou 730000, China 3. Institute of Oceanology, Chinese Academy of Sciences, Qingdao 266071, China Lanzhou Institute of Geology Chinese Academy of Sciences Lanzhou China Earthquake Research Institute of Lanzhou SSB Lanzhou China Institute of Oceanology Chinese Academy of Sciences Qingdao China

sinking particulate organic matter of the sea plays an important role in marine environment. Itnot only provides food for marine organisms and takes part in chemical cycling, but also pro-vides sedimentary organic matter for marine sediments. Therefore, researchers always payclose attention to the source and processes of transport and transformation of marine sinkingparticulate organic matter. Its transport process can be understood by measuring the

关键词： marine sinking paniculate material composition of lipid compounds organic matter source and biochemical pro-cesses.

The Effect of the sinking of Isotope Grains in Water Injection Profile Logging

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Petroleum Science 2006年第1期3卷 45-49页

作者： Zhang Yusheng Jiang Quan Xia Yuanjian Tuha Business Division of China Petroleum Logging Co. Ltd. Shanshan Xinjiang 838202 China

In the process of oil field exploitation, radioactive isotope tracer water injection profile logging is a main method to determine the water-intake capacity of the target intervals. For those general water injection wells, whose perforated intervals are beyond the tubing shoe, the sinking speed of isotope grains is related to the density and salinity of the injection water and the tubing dimension. We studied the motion of the isotope grains in the water injection wells by both theoretical calculation and field experiment. The result shows that if the water injection quantity is over 20 m＆3/d, and the density of the isotope grains, whose diameter is 100-600 μm, is 1.06 g/cm^3, then the logging technique for this kind of water injection wells will be appropriate. Whether water injection profile logging is successful in the well, whose perforated intervals are beyond the tubing shoe, depends on the sinking speed of the tracer grains.

关键词： Isotope tracer logging injection water profile sinking calculation experiment

Organic geochemical studies of sinking particulate material in China sea area(I)──Organic matter fluxes and distributional features of hydrocarbon compounds and fatty acids

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Science China Earth Sciences 1998年第2期41卷 208-214页

作者：段毅宋金明崔明中罗斌杰

sinking particulate material collected from Nansha Yongshu reef lagoon and the continental shelf of the East China Sea by sediment traps has been analyzed and studied for the first time using organic geochemical method. The results show that about half of the sinking particulate organic matter in the two study areas are consumed before reaching the depth of 5 m to the sea floor and the degree of this consumption in Yongshu reef lagoon is larger than that in the continental shelf of the East China Sea. The distributions of hydrocarbons and fatty acids indicate that the minor difference of biological sources of sinking particulate organic matter exists between Yongshu reef lagoon and the continental shelf of the East China Sea, but they mainly come from marine plankton. Stronger biological and biochemical transformations of sinking particulate organic matter are also observed and the intensity of this transformation in Yongshu reef lagoon is greater than that in the continental shelf of the East China Sea. It is found that the occurrence of C 25 highly branched isoprenoid (HBI) diene may be related to the composition of diatom species.

关键词： marine sinking particulate organic matter lipid compounds organic matter flux biological source biological and biochemical process

Particle Association of Enterococcus and Total Bacteria in the Lower Hudson River Estuary, USA

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Journal of Water Resource and Protection 2011年第10期3卷 715-725页

作者： Elizabeth Suter Andrew R. Juhl Gregory D. O’Mullan 不详

Bacterial particle association has important consequences for water-quality monitoring and modeling. Particle association can change vertical and horizontal transport of bacterial cells, as well as patterns of persistence and production. In this study, the abundance and particle association of total bacteria and the fecal-indicator, Enterococcus, were quantified between June and October 2008 in the lower Hudson River Estuary (HRE). Twelve sites were sampled, including mid-channel, near shore, and tributary habitats, plus a sewage outfall. Total bacterial cell counts averaged 9.2 × 109 ± 6.4 × 109 cell l–1 (1 standard deviation), comparable to previous sampling in the HRE. Unlike earlier studies, bacterial abundance did not change consistently along the north/south estuarine salinity gradient. Enterococcus concentrations were highly variable, but mid-channel stations had significantly lower values than other habitat categories. Counts of total bacteria and Enterococcus were both correlated with turbidity, which was also significantly lower at mid-channel stations. A larger fraction of Enterococci were associated with particles (52.9 ± 20.9%, 1 standard deviation) than in the pool of total bacteria (23.8 ± 15.0%). This high frequency of particle association, relative to total bacteria, could cause Enterococcus to be preferentially retained near input sources because of enhanced deposition to bottom sediments, where they would be available for later resuspension. In turn, retention and resuspension in nearshore environments may explain the observed cross-channel variability of turbidity and Enterococcus. Assessments and predictive models of estuarine water quality may be improved by incorporating cross-channel variability and the effects of particle association on key indicators.

关键词： Attachment Fecal Indicator Bacteria Sedimentation sinking Rate Sewage

Possible Effect of Pressure Solution on the Movement of a Canister in the Buffer of Geological Disposal System

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International Journal of Geosciences 2017年第2期8卷 167-180页

作者： Koichi Shin Central Research Institute of Electric Power Industry Tokyo Japan

One of the major concepts of the geological disposal of high level radioactive waste is to enclose a metallic container with bentonite buffer which is considered to be impermeable and chemically stable. Since the average density of the container is around 6 to 7 and very heavy compared to bentonite, the scenario of container sinking has been evaluated because excess sinking makes short the pathway of nuclide migration in the bentonite and is detrimental to the safety of the disposal system. Previous considerations on container sinking have been made from the viewpoint of mechanical deformation of the bentonite. In this paper, a chemical deformation process is presented as another mechanism of container sinking, which has not been previously considered for the container sinking in the field of radioactive waste disposal. The chemical deformation mentioned in this paper is the deformation through the process of pressure solution of minerals constituting the buffer, transportation by diffusion and precipitation. That such chemical deformation is a ubiquitous phenomenon occurring in various scales in the crust of the earth will be shown through the review of previous works. Then, some future research topics will be suggested which would be required in order to evaluate the container sinking in the safety case for radioactive waste disposal.

关键词： Safety Case Buffer Deformation Pressure Solution Canister sinking Geological Disposal

Increasing Visitor Knowledge of Park History and Natural Resources via Non-Traditional Recreation: An Exploratory Study of Quicksand Enthusiasts

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Natural Resources 2019年第9期10卷 358-366页

作者： Charles K. Mullins Michael J. Bradley Lashé D. Mullins James N. Maples Division of Humanities and Social Sciences Alice Lloyd College Pippa Passes USA Department of Recreation and Park Administration Eastern Kentucky University Richmond USA Department of Anthropology Sociology and Social Work Eastern Kentucky University Richmond USA

Sinkers are quicksand enthusiasts that crave the sensation of being trapped in deep mud while being sucked downward. Although humans have been interested in quicksand over the years (particularly through film), there remains a void of research into the meaning and value in the lives of those who engage in a recreational pursuit of quicksand, most notably the community of individuals who self-describe as sinkers. The purpose of this exploratory study was to examine if sinking can contribute to a participant’s understanding of history and natural resources at state parks. In order to obtain a better understanding of the effects, a qualitative study was conducted in the summer of 2016 at Stephen C. Foster State Park, a state park adjacent to Okefenokee Swamp. The researchers exercised grounded theory techniques and inductive content analysis to analyze interview data and compile coded text into four main categories: learning, enjoyment, traveling, and economic impact. Findings suggest that participants believed their knowledge of park history and natural resources increased through a recreational pursuit of quicksand.

关键词： Quicksand Sinkers sinking Qualitative Research Park Management History Natural Resources

Properties of Ceramic Fiber and Ceramic Shot in Wet-laid Processes

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Journal of Donghua University(English Edition) 2002年第3期19卷 115-117页

作者：程隆棣 College of Textiles Dong Hua UniversityShanghai200051

The paper deals with the different sinking properties of ceramic fiber and the ceramic shot in wetlaid nonwoven processes. The difference between the sinking properties of the fiber and the shot is very great according to theory analysis and the test. From results of calculating and practical testing, the method of removing ceramic shots during manufacturing is put forward.

关键词： ceramic fiber, ceramic shot, sinking property,index of sinking.

Differentiation of Material Temperature through the Application of Increased Localized Dissolution via Heat Transfer

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Journal of Analytical Sciences, Methods and Instrumentation 2015年第3期5卷 44-46页

作者： Brian K. Chen Chemistry Creative Secondary School Hong Kong China

Increased temperature of a solution increases its solubility, allowing for a greater level of dissolution of the solute. A greater level of dissolution will result in a change in the density of the solution. When a localized area of the solution is of a different temperature, this will affect the localized density. Density is one of the factors affecting rate of sinking and the difference in temperature will lead to a change in the rate of sinking. Thus, when an object is at different temperatures, it will transfer heat to or from the solution in different manners and the rate of sinking will be different. This study tested whether sinking rate in a solution with excess solute could be used to judge the temperature of an object and the effect was confirmed with impure Graphite blocks in a Potassium Iodide solution.

关键词： Calorimetry Localized Heat Transfer Density sinking

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中国大陆教育社会学三十年停滞沉沦之反思