317 research outputs found
Thermal Behaviour of Corn/Cotton Stalk Blends during Co-pyrolysis
AbstractThe pyrolysis behaviors and pyrolysis kinetics of corn straw (YM), cotton stalk(MG) and blends at different proportion were studied by TG-DSC technique. The results indicate that two kinds of biomass straw can be mixed fully. The pyrolysis process with its blend ratio is not a linear relationship and solid product reduced compared with single-stalk. In addition, the major pyrolysis process of mixture within the main range can be well described by a two-dimensional diffusion model with Malek method. Among the tested samples, the 40:60 MG/ YM blend shows the lowest activation energy of 51.7 KJ/mol. Besides corn straw plays a dominant role on the course of the thermal conversion. The experimental results may provide useful data to promote the application of biomass thermochemical conversion technology of biomass mixture
Simulation of Parallel Beam CT Reconstruction Algorithm Based on Grating Phase Contrast Imaging
X-ray phase contrast imaging has higher resolution in the imaging of light element materials than absorption imaging, and is increasingly used in many fields such as medicine, biology and materials science.Grating phase contrast imaging stands out among many phase contrast imaging methods due to its unique advantages.This paper briefly introduces the filtering back projection reconstruction algorithm of the traditional parallel beam CT, and then introduces the Hilbert filter back projection algorithm suitable for the parallel beam CT of the grating phase contrast. Finally, the simulation of the parallel beam CT reconstruction algorithm based on the grating phase contrast imaging is carried out.Through the detailed introduction of the realization principle of traditional CT imaging and phase contrast CT imaging, it can be seen that there is no essential difference between the two implementation principles.The reconstruction algorithm of traditional CT imaging is mature, and then only needs to be slightly improved to be suitable for CT reconstruction based on grating phase contrast imaging
Cloaking and imaging at the same time
In this letter, we propose a conceptual device to perform subwavelength
imaging with positive refraction. The key to this proposal is that a drain is
no longer a must for some cases. What's more, this device is an isotropic
omnidirectional cloak with a perfect electric conductor hiding region and shows
versatile illusion optical effects. Numerical simulations are performed to
verify the functionalities.Comment: 15 pages, 4 figure
Knowledge domain, research hotspots and frontiers in physiology teaching reforms from 2012 to 2021: A bibliometric and knowledge-map analysis
ObjectiveTo identify author collaborations and impact; participating countries, institutions, and journals; evaluate the knowledge base; and analyze research hotspots and frontiers in teaching reforms in physiology.MethodsArticles and reviews related to teaching reforms in physiology published between January 1, 2012, and December 31, 2021, were obtained from the Web of Science Core Collection. Two Scientometric software applications (CiteSpace 5.7 and VOSviewer 1.6.15) were used to perform bibliometric and knowledge-map analysis, generate network maps, and identify research trends and top keywords, authors, co-cited authors, institutions, countries, journals, and references.ResultsThe search identified a total of 2,882 papers in 466 academic journals by 13,895 authors from 4,072 organizations in 67 countries/regions. Physiology teaching reform-related publications increased rapidly over time. Arango-Lasprilla and Rivera published the most papers, while Moseley had the most co-citations. Active collaborations among physiology researchers were noted. Advances in Physiology Education published the most papers on physiology teaching reforms and was also the top co-cited journal in the Medicine/Medical/Clinical, Psychology/Education/Health, and Neurology/Sports/Ophthalmology fields. The United States and University of California published the most physiology teaching publications in the search criteria. Ten references (research articles and reviews) on mechanisms and diseases were identified as the knowledge base. The mainstream research directions were education, Alzheimer’s disease, performance, physiology, and risk factors. Mental health and emotion regulation are increasing in significance and may become new hotspots. The research trend to move from the field of pain pathogenesis to the field of neuropsychiatry has become increasingly clear. This tendency away from peripheral system-based disorders to central system-based orders is inextricably linked to further developments in physiological understanding of the brain.ConclusionThis study analyzed the research hot spots and frontiers of teaching reforms on in physiology using bibliometric and visual methods. Based on the results, rehabilitation, neurosciences, and infectious disease are hot topics in physiology. In particular, the pathogenesis of neurological diseases, treatment strategies, and technology updates have gradually become research hotspots. We predict that this trend is closely related to the implementation of brain research programs in various countries. These findings provide helpful references for scholars focusing on physiology education
An Efficient Virus-Induced Gene Silencing System for Functional Genomics Research in Walnut (Juglans regia L.) Fruits
The Persian walnut (Juglans regia L.) is a leading source of woody oil in warm temperate regions and has high nutritional and medicinal values. It also provides both tree nuts and woody products. Nevertheless, incomplete characterization of the walnut genetic system limits the walnut gene function analysis. This study used the tobacco rattle virus (TRV) vector to construct an infectious pTRV-JrPDS recombinant clone. A co-culture inoculation method utilizing Agrobacterium was screened out from four inoculation methods and optimized to set up an efficient virus-induced gene silencing (VIGS) system for J. regia fruit. The optimized VIGS-TRV system induced complete photobleaching phenotype on the walnut fruits of four cultivars, and the JrPDS transcript levels decreased by up to 88% at 8 days post-inoculation (dpi). While those of browning-related J. regia polyphenol oxidase (PPO) genes JrPPO1 and JrPPO2 decreased by 67 and 80% at 8 dpi, respectively, accompanied by a significant reduction in fruit browning phenotype. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis screening and Western Blot showed that the PPO protein levels were significantly reduced. Moreover, a model of TRV-mediated VIGS system for inoculating J. regia fruit with efficient silence efficiency via co-culture was developed. These results indicate that the VIGS-TRV system is an efficient tool for rapid gene function analysis in J. regia fruits
An invisibility cloak using silver nanowires
In this paper, we use the parameter retrieval method together with an
analytical effective medium approach to design a well-performed invisible
cloak, which is based on an empirical revised version of the reduced cloak. The
designed cloak can be implemented by silver nanowires with elliptical
cross-sections embedded in a polymethyl methacrylate host. This cloak is
numerically proved to be robust for both the inner hidden object as well as
incoming detecting waves, and is much simpler thus easier to manufacture when
compared with the earlier proposed one [Nat. Photon. 1, 224 (2007)].Comment: 7 pages, 4 figures, 2 table
Growth of millimeter-sized high-quality CuFeSe single crystals by the molten salt method and study of their semiconducting behavior
An eutectic AlCl/KCl molten salt method in a horizontal configuration was
employed to grow millimeter-sized and composition homogeneous CuFeSe single
crystals due to the continuous growth process in a temperature gradient induced
solution convection. The typical as-grown CuFeSe single crystals in cubic
forms are nearly 1.61.21.0 mm3 in size. The chemical
composition and homogeneity of the crystals was examined by both inductively
coupled plasma atomic emission spectroscopy and energy dispersive spectrometer
with Cu:Fe:Se = 0.96:1.00:1.99 consistent with the stoichiometric composition
of CuFeSe. The magnetic measurements suggest a ferrimagnetic or weak
ferromagnetic transition below T = 146 K and the resistivity reveals a
semiconducting behavior and an abrupt increase below T
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