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journal of Hydrodynamics 2022年第5期34卷 806-825页

作者： christopher j.keylock School of Architecture Building and Civil EngineeringLoughborough UniversityLeicestershireUK

The Schur decomposition of the velocity gradient tensor(VGT)is an alternative to the classical Cauchy-Stokes decomposition into rotation rate and strain rate ***,there have been several strands of work that have employed this decomposition to examine the physics of turbulence dynamics,including approaches that combine the Schur and Cauchy-Stokes *** are briefly reviewed before the latter approach is set *** partitions the rotation rate and strain rate tensors into normal/local and non-normal/non-local *** then study the relation between the VGT dynamics and ejection-sweep events in a channel flow *** show that the sweeps in particular exhibit novel behaviour compared with either the other quadrants,or the flow in general,with a much-reduced contribution to the dynamics from the non-normal terms above the viscous *** particular,the reduction in the production term that is the interaction between the non-normality and the normal straining reduces in the log-layer as a consequence of an absence of alignment between the non-normal vorticity and the strain rate *** have been early forays into using the Schur transform approach for subgrid-scale modelling in large-eddy simulation(LES)and this would appear to be an exciting way forward.

关键词： Turbulence channel flow velocity gradient tensor Schur decomposition

Apples to oranges:environmentally derived,dynamic regulation of serotonin neuron subpopulations in adulthood?

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Neural Regeneration Research 2025年第9期20卷 2596-2597页

作者： christopher j.O’Connell Matthew j.Robson Department of Genetics College of MedicineHarvard UniversityBostonMAUSA james L.Winkle College of Pharmacy Division of Pharmaceutical SciencesUniversity of CincinnatiCincinnatiOHUSA Neuroscience Graduate Program College of MedicineUniversity of CincinnatiCincinnatiOHUSA

Traumatic brain injury(TBI)is a public health problem with an undue economic burden that impacts nearly every age,ethnic,and gender group across the globe(Capizzi et al.,2020).TBIs are often sustained during a dynamic range of exposures to energetic environmental forces and as such outcomes are typically heterogeneous regarding severity and pathology(Capizzi et al.,2020).

关键词： sustained orange dynamic

Development process for a higher capacity Propsetter~ system

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International journal of Mining Science and Technology 2018年第1期28卷 121-126页

作者： christopher j.Brown Product Development-Strata Worldwide LLC

As longwall tailgate support technologies continue to be developed and improved, strata worldwide has worked to design and manufacture a revised Propsetter to provide additional support capacity and enable applications at greater mine *** support is targeted for tailgate applications, however, it can also be utilized for roof support in various types of mining *** paper describes the design changes for enhancing the support capacity of the Propsetter to more closely align its performance with other support technologies currently being employed in longwall *** changes to each design aspect of the Propsetter was key to successfully improving the roof support's load capacity while maintaining controlled *** the load capacity would allow a mine to improve support efficiency with a smaller, less intrusive support compared to support alternatives and reduce the cost per foot of supported *** target support capacity was 711–890 k N at 50 mm of deformation to more closely match the performance of competing tailgate supports such as the 610 mm-diameter CAN~.To achieve this goal, changes were made to all design aspects of the Propsetter: diameter, wedge cut depth and angle, pod size, and confinement *** results from the NIOSH Mine Roof Simulator verified that these design changes were successful in increasing the capacity of the Propsetter to the 711–890 k N range at fifty mms of deformation.

关键词： Propsetter Can Longwall mining Tailgate roof support Controlled deformation

Plasma-catalysis: Is it just a question of scale?

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Frontiers of Chemical Science and Engineering 2019年第2期13卷 264-273页

作者： j.christopher Whitehead School of Chemistry The University of ManchesterManchester M13 9PLUK

The issues of describing and understanding the changes in performance that result when a catalyst is placed into plasma are discussed. The different chemical and physical interactions that result and how their combination might produce beneficial results for the plasma-catalytic processing of different gas streams are outlined with particular emphasis being placed on the different range of spatial and temporal scales that must be considered both in experiment and modelling. The focus is on non-thermal plasma where the lack of thermal equilibrium creates a range of temperature scales that must be considered. This contributes in part to a wide range of inhomogeneity in different properties such as species concentrations and electric fields that must be determined experimentally by in situ methods and be incorporated into modelling. It is concluded that plasmacatalysis is best regarded as conventional catalysis perturbed by the presence of a discharge, which modifies its operating conditions, properties and outcomes often in a very localised way. The sometimes used description "plasma-activated catalysis" is an apt one.

关键词： plasma catalysis plasma-activated catalysis non-thermal plasma CO2 conversion

Endocasts-the direct evidence and recent advances in the study of human brain evolution

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Progress in Natural Science:Materials International 2007年第9期17卷 993-1002页

作者： christopher j.Norton 86011-4099 AZ Beijing 100044 China Flagstaff Institute of Vertebrate Paleontology and Paleoanthropology Chinese Academy of Sciences Laboratory of Quaternary Paleontology Northern Arizona University USA

Brain evolution is one of the most important aspects of human evolution,usually studied through *** of fossil hominid endocasts allows inferences on functional anatomy,physiology,and *** this paper,we describe the general features of endocast studies and review some of the major topics in *** are:absolute and relative brain size evolution;brain shape variation;brain asymmetry and lateralization;middle meningeal vessels and venous sinuses;application of computed tomography and virtual imaging;the history of Chinese brain endocast *** particular,this review emphasizes endocast studies on Chinese hominin fossils.

关键词： endocast human fossil brain evolution cranial capacity human evolution

Structural subgrid-scale modeling for large-eddy simulation: A review

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Acta Mechanica Sinica 2016年第4期32卷 567-578页

作者： Hao Lu christopher j.Rutland School of Energy and Power Engineering Huazhong University of Science and Technology Engine Research Center Mechanical EngineeringUniversity of Wisconsin-Madison

Accurately modeling nonlinear interactions in turbulence is one of the key challenges for large-eddy simulation（LES） of turbulence. In this article, we review recent studies on structural subgrid scale modeling, focusing on evaluating how well these models predict the effects of small scales. The article discusses a priori and a posteriori test results. Other nonlinear models are briefly discussed, and future prospects are noted.

关键词： turbulence turbulent viscosity priori dissipation posteriori scalar A review scales Reynolds

An In Vivo Experimental Validation of a Computational Model of Human Foot

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journal of Bionic Engineering 2009年第4期6卷 387-397页

作者： christopher j.Nester David Howard Centre for Health Sport and Rehabilitation Sciences ResearchUniversity of Salford Salford M5 4WTUK

Reliable computational foot models offer an alternative means to enhance knowledge on the biomechanics of human foot. Model validation is one of the most critical aspects of the entire foot modeling and analysis *** paper presents an in vivo experiment combining motion capture system and plantar pressure measure platform to validate a three-dimensional finite element model of human *** Magnetic Resonance Imaging(MRI)slices for the foot modeling and the experimental data for validation were both collected from the same volunteer *** validated components included the comparison of static model predictions of plantar force,plantar pressure and foot surface deformation during six loading conditions,to equivalent measured *** the whole experiment,foot surface deformation,plantar force and plantar pressure were recorded simultaneously during six different loaded standing *** predictions of the current FE model were in good agreement with these experimental results.

关键词： human foot computational model plantar pressure

Thermally-actuated microfluidic membrane valve for point-of-care applications

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Microsystems & Nanoengineering 2021年第3期7卷 197-208页

作者： Muhsincan Sesen christopher j.Rowlands Department of Bioengineering Imperial College LondonLondonSW72AZUK

Microfluidics has enabled low volume biochemistry reactions to be carried out at the point-of-care.A key component in microfluidics is the microfluidic *** valves are not only useful for directing flow at intersections but also allow mixtures/dilutions to be tuned real-time and even provide peristaltic pumping *** the transition from chip-in-a-lab to lab-on-a-chip,it is essential to ensure that microfluidic valves are designed to require less peripheral equipment and that they are *** this paper,a thermally-actuated microfluidic valve is *** valve itself is fabricated with off-the-shelf components without the need for sophisticated cleanroom *** is shown that multiple valves can be controlled and operated via a power supply and an Arduino microcontroller;an important step towards transportable microfluidic devices capable of carrying out analytical assays at the *** is been calculated that a single actuator costs less than$1,this highlights the potential of the presented valve for scaling *** valve operation is demonstrated by adjusting the ratio of a water/dye mixture in a continuous flow microfluidic chip with Y-junction channel *** power required to operate one microfluidic valve has been characterised both theoretically and *** operation of the valve has been demonstrated for 65 h with 585 *** presented valve is capable of actuating rectangular microfluidic channels of 500μm×50μm with an expected temperature increase of up to 5°*** fastest actuation times achieved were 2 s for valve closing(heating)and 9 s for valve opening(cooling).

关键词： fluid valve Arduino

Adventures and lessons of an American biochemist in China

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Protein & Cell 2011年第8期2卷 601-603页

作者： christopher j.Vavricka CAS Key Laboratory of Pathogenic Microbiology and Immunology Institute of MicrobiologyChinese Academy of SciencesBeijing 100101China

It’s very interesting how events often lead up to each other seemingly by chance,but appear almost perfectly planned out when looking *** the past two years,I have worked as an International Young Scientist Research Fellow at the Institute of Microbiology,Chinese Academy of Sciences in Beijing,*** people ask me,especially Chinese graduate students,why an American would choose to come to China as a postdoctoral researcher.

关键词： looking doctor perfectly

Strategies towards statistically robust interpretations of in situ U-Pb zircon geochronology

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Geoscience Frontiers 2016年第4期7卷 581-589页

作者： christopher j.Spencer christopher L.Kirkland Richard j.M.Taylor The Institute of Geoscience Research(TIGeR) Department of Applied GeologyWestern Australian School of MinesCurtin UniversityWA 6102Australia Centre for Exploration Targeting-Curtin Node Department of Applied GeologyWestern Australian School of MinesCurtin UniversityWA 6102Australia Australian Research Council Centre of Excellence for Core to Crust Fluid SystemsPerthWA 6102Australia

Zircon U-Pb geochronology has become a keystone tool across Earth science, arguably providing the gold standard in resolving deep geological time. The development of rapid in situ analysis of zircon （via laser ablation and secondary ionization mass spectrometry） has allowed for large amounts of data to be generated in a relatively short amount of time and such large volume datasets offer the ability to address a range of geological questions that would otherwise remain intractable （e.g. detrital zircons as a sedi- ment fingerprinting method）. The ease of acquisition, while bringing benefit to the Earth science com- munity, has also led to diverse interpretations of geochronological data. In this work we seek to refocus U -Pb zircon geochronology toward best practice by providing a robust statistically coherent workflow. We discuss a range of data filtering approaches and their inherent limitations （e.g. discordance and the reduced chi-squared; MSWD）. We evaluate appropriate mechanisms to calculate the most geologically appropriate age from both 238U/206pb and 207pb/206pb ratios and demonstrate the cross over position when chronometric power swaps between these ratios. As our in situ analytical techniques become progressively more precise, appropriate statistical handing of U-Pb datasets will become increasingly pertinent.

关键词： Zircon Geochronology U-Pb Geostatistics MSWD