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排序方式: 共有339条查询结果,搜索用时 31 毫秒
71.
Moreno Paalo Villamizar Nicole Perez Jefferson Bayona Angelica Roman Jesús Moreno Nicolás Cardozo Nilo Sergio Medeiros 《Clean Technologies and Environmental Policy》2021,23(5):1537-1546
Clean Technologies and Environmental Policy - Housing construction consumes more materials than any other economic activity, with a total of 40.6 Gt/year. Boards are placed between... 相似文献
72.
73.
The paper describes the investigation of how the make up of raw water influences the physical properties of flocculated suspensions. The work focuses on the properties of four characteristic organic fractions separated as a function of their hydrophobicity. Mesoscale data indicates that the hydrophobic fractions dominate the make up of the water and are the most easily removed. Microscale and nanoscale data reveals that the fulvic acid fraction (FAF) generates statistically smaller and more compact flocs than those formed by the other fractions and the hydrophilic fractions form the most internally open and dendritic structures. The FAF fraction was also seen to dominate the zeta potential response of the raw water. 相似文献
74.
JW Jefferson 《Canadian Metallurgical Quarterly》1998,316(7141):1330-1331
75.
Kang-Shi Wang Chien-Hou Wu Jefferson L. Creek Patrick J. Shuler Yongchun Tang 《Petroleum Science and Technology》2003,21(3):369-379
Deposition from decane solutions of model paraffins such as n-C24H50 (C24), and n-C36H74 (C36), as well as a mixture of n-alkanes (C21 to C44) was examined with and without chemical wax deposition inhibitors. The device used to produce the deposits investigated was a “Cold Disk” Wax Deposition Apparatus (CoDWaD) capable of producing field like deposits with relatively small volumes of oil in minutes. It was found that most of commercial wax inhibitors tested could decrease the deposition of low molecular weight paraffins (C34 and below), while having little effect on the wax deposition for high molecular weight paraffins (C35-C44). In many cases, although the total amount of wax formed on the cold plate was reduced, the absolute amount of deposition for high molecular wax was actually increased. Therefore, the net effect of many commercial inhibitors is to make even harder wax under the tests conditions studied here. One intriguing result was that the addition of an oleic imidazoline c rrosion inhibitor improved the performance of two wax inhibitors tested. It was also observed that there are subtle differences in inhibitor performance depending on whether the test solutions are binary mixtures, synthetic wax mixtures, or crude oil. 相似文献
76.
Bernal MP Burr GW Coufal H Grygier RK Hoffnagle JA Jefferson CM Oesterschulze E Shelby RM Sincerbox GT Quintanilla M 《Applied optics》1997,36(14):3107-3115
We study the interpixel cross talk introduced to digital holographic data storage by use of a multilevel phase mask at the data-input plane. We evaluate numerically the intensity distribution at the output detector for Fourier plane hologram storage in a limited-aperture storage medium. Only the effect at an output pixel of interpixel cross talk from the four horizontal and vertical neighboring pixels is considered, permitting systematic evaluation of all possibilities. For random two-level and pseudorandom six-level phase masks, the influence of the pixel fill factor, as well as the aperture size of the storage medium, is studied. Our simulations show that, for a given aperture size, a random two-level mask is more susceptible to interpixel cross talk than is a pseudorandom six-level mask. Decreasing the pixel fill factor below 94% with a pseudorandom six-level phase mask makes it theoretically possible to have a system with no errors from interpixel cross talk if one particular 5-pixel pattern is forbidden through modulation coding. Reducing the input fill factor below 85% means that no patterns need to be excluded. 相似文献
77.
BACKGROUND: Conditions once considered bad habits are now recognized as psychiatric disorders (trichotillomania, onychopagia). We hypothesized that nose picking is another such "habit," a common benign practice in most adults but a time-consuming, socially compromising, or physically harmful condition (rhinotillexomania) in some. METHODS: We developed the Rhinotillexomania Questionnaire, mailed it to 1000 randomly selected adult residents of Dane County, Wisconsin, and requested anonymous responses. The returned questionnaires were analyzed according to age, sex, marital status, living arrangement, and educational level. Nose picking was characterized according to time involved, level of distress, location, attitudes toward self and others regarding the practice, technique, methods of disposal, reasons, complications, and associated habits and psychiatric disorders. RESULTS: Two hundred fifty-four subjects responded. Ninety-one percent were current nose pickers although only 75% felt "almost everyone does it"; 1.2% picked at least every hour. For 2 subjects (0.8%), nose picking caused moderate to marked interferences with daily functioning. Two subjects spent between 15 and 30 minutes and 1 over 2 hours a day picking their nose. For 2 others, perforation of the nasal septum was a complication. Associated "habits" included picking cuticles (25%), picking at skin (20%), biting fingernails (18%), and pulling out hair (6%). CONCLUSION: This first population survey of nose picking suggests that it is an almost universal practice in adults but one that should not be considered pathologic for most. For some, however, the condition may meet criteria for a disorder-rhinotillexomania. 相似文献
78.
Bernal MP Coufal H Grygier RK Hoffnagle JA Jefferson CM Macfarlane RM Shelby RM Sincerbox GT Wimmer P Wittmann G 《Applied optics》1996,35(14):2360-2374
The design and the realization of an advanced precision optical test stand for evaluating materials and developing tools and techniques for holographic digital data storage are described. This apparatus allows studies of holographic recording materials and recording physics to be performed in the context of practical data storage. The system concept, its implementation, and its performance are described, and examples of holographic storage in photorefractive materials are discussed. 相似文献
79.
Will Usher Ingo Wald Jefferson Amstutz Johannes Günther Carson Brownlee Valerio Pascucci 《Computer Graphics Forum》2019,38(3):455-466
Image‐ and data‐parallel rendering across multiple nodes on high‐performance computing systems is widely used in visualization to provide higher frame rates, support large data sets, and render data in situ. Specifically for in situ visualization, reducing bottlenecks incurred by the visualization and compositing is of key concern to reduce the overall simulation runtime. Moreover, prior algorithms have been designed to support either image‐ or data‐parallel rendering and impose restrictions on the data distribution, requiring different implementations for each configuration. In this paper, we introduce the Distributed FrameBuffer, an asynchronous image‐processing framework for multi‐node rendering. We demonstrate that our approach achieves performance superior to the state of the art for common use cases, while providing the flexibility to support a wide range of parallel rendering algorithms and data distributions. By building on this framework, we extend the open‐source ray tracing library OSPRay with a data‐distributed API, enabling its use in data‐distributed and in situ visualization applications. 相似文献
80.
Araújo José Denes Lima Souza Johnatan Carvalho Neto Otilio Paulo Silva de Sousa Jefferson Alves de Almeida João Dallyson Sousa de Paiva Anselmo Cardoso Silva Aristófanes Corrêa Junior Geraldo Braz Gattass Marcelo 《Multimedia Tools and Applications》2019,78(10):12987-13004
Multimedia Tools and Applications - Glaucoma is the second major cause of vision loss worldwide. It is usually caused by the increase in the intraocular pressure, which damages the optic nerve... 相似文献