Fine Surface Structure of Large-Scale Tetraphenylporphine Aggregates

2004 ◽  
Vol 66 (4) ◽  
pp. 489-494 ◽  
Author(s):  
A. V. Udal'tsov ◽  
G. Kaupp ◽  
A. I. Taskaev
Keyword(s):  
Surface Structure ◽  
Large Scale ◽  
Fine Surface

scholarly journals The influence of cactus spine surface structure on puncture performance and anchoring ability is tuned for ecology

2018 ◽  
Vol 285 (1891) ◽  
pp. 20182280 ◽  
Author(s):  
S. B. Crofts ◽  
P. S. L. Anderson
Keyword(s):  
Surface Structure ◽  
Large Scale ◽  
Biological Materials ◽  
Morphological Features ◽  
Ecological Functions ◽  
Defensive Mechanisms ◽  
Evolutionary Convergence ◽  
Almost All

Spines are common morphological features found in almost all major biological groups offering an opportunity to explore large-scale evolutionary convergence across disparate clades. As an example, opuntioid cacti have spines with barbed ornamentation that is remarkably similar in form and scale to that found on porcupine quills, suggesting specific biomechanical convergence across the animal and plant kingdoms. While the mechanics of porcupine quills as defensive mechanisms has been previously tested, the mechanics of cactus spines (which have evolved to fill a number of functions including defence, climbing and dispersal) has not been characterized. Here we study the puncturing and anchoring ability of six species of cactus, including both barbed and non-barbed spines. We found that barbed spines require less work to puncture a variety of targets than non-barbed spines. Barbed spines also require more work than non-barbed spines to withdraw from biological materials, owing to their barbs engaging with tissue fibres. These results closely match those found previously for barbed versus non-barbed porcupine quills, implying biomechanical convergence. The variation in performance of barbed versus non-barbed spines, as well as between barbed spines from different species, is probably tied to the diversity of ecological functions of cactus spines.

Highly ordered surface structure of large-scale porphyrin aggregates assembled from protonated TPP and water

2014 ◽  
Vol 1065-1066 ◽  
pp. 170-178 ◽  
Author(s):  
Alexander V. Udal’tsov ◽  
Anastasia V. Bolshakova ◽  
Johannes G. Vos
Keyword(s):  
Surface Structure ◽  
Large Scale

scholarly journals Limitations of using a thermal imager for snow pit temperatures

2014 ◽  
Vol 8 (2) ◽  
pp. 387-394 ◽  
Author(s):  
M. Schirmer ◽  
B. Jamieson
Keyword(s):  
Surface Structure ◽  
Large Scale ◽  
Structural Changes ◽  
Thermal Structure ◽  
Large Temperature ◽  
Small Scale ◽  
Thermal Imager ◽  
Snow Layer ◽  
Ir Camera ◽  
Near Surface

Abstract. Driven by temperature gradients, kinetic snow metamorphism plays an import role in avalanche formation. When gradients based on temperatures measured 10 cm apart appear to be insufficient for kinetic metamorphism, faceting close to a crust can be observed. Recent studies that visualised small-scale (< 10 cm) thermal structures in a profile of snow layers with an infrared (IR) camera produced interesting results. The studies found melt-freeze crusts to be warmer or cooler than the surrounding snow depending on the large-scale gradient direction. However, an important assumption within these studies was that a thermal photo of a freshly exposed snow pit was similar enough to the internal temperature of the snow. In this study, we tested this assumption by recording thermal videos during the exposure of the snow pit wall. In the first minute, the results showed increasing gradients with time, both at melt-freeze crusts and artificial surface structures such as shovel scours. Cutting through a crust with a cutting blade or shovel produced small concavities (holes) even when the objective was to cut a planar surface. Our findings suggest there is a surface structure dependency of the thermal image, which was only observed at times during a strong cooling/warming of the exposed pit wall. We were able to reproduce the hot-crust/cold-crust phenomenon and relate it entirely to surface structure in a temperature-controlled cold laboratory. Concave areas cooled or warmed more slowly compared with convex areas (bumps) when applying temperature differences between snow and air. This can be explained by increased radiative and/or turbulent energy transfer at convex areas. Thermal videos suggest that such processes influence the snow temperature within seconds. Our findings show the limitations of using a thermal camera for measuring pit-wall temperatures, particularly during windy conditions, clear skies and large temperature differences between air and snow. At crusts or other heterogeneities, we were unable to create a sufficiently planar snow pit surface and non-internal gradients appeared at the exposed surface. The immediate adjustment of snow pit temperature as it reacts with the atmosphere complicates the capture of the internal thermal structure of a snowpack with thermal videos. Instead, the shown structural dependency of the IR signal may be used to detect structural changes of snow caused by kinetic metamorphism. The IR signal can also be used to measure near surface temperatures in a homogenous new snow layer.

An Analysis of Object Oriented Testing Techniques

2016 ◽  
Vol 11 (01) ◽  
Author(s):  
Rashmi Trivedi Sharma
Keyword(s):  
System Design ◽  
Surface Structure ◽  
Message Passing ◽  
Large Scale ◽  
Object Oriented ◽  
Structural Testing ◽  
Dynamic Binding ◽  
Fast Pace ◽  
New Methodologies ◽  
Testing Techniques

In today’s fast pace world, large scale system design is sought for, and to fulfill this need Object-oriented paradigm is the solution. It includes various distinguished features that are not involved in their conventional analogues. Example: Encapsulation, Polymorphism, Object instantiation, Persistence, Synchronization, Message Passing, Inheritance, and Dynamic Binding etc. Hence, Testing for such programs becomes even more tedious than that for stereotyped programs. In this paper we have discussed about the testing being carried out in the Object Oriented domain. In order to conform to this, several new methodologies have been proposed like Scenario based testing, Deep structural testing, Surface structure testing, and fault-based techniques.

Characterization of Fine Surface Structure with a New Electron Detection System in FE-SEM

2012 ◽  
Vol 18 (S2) ◽  
pp. 932-933
Author(s):  
N. Erdman ◽  
Y. Sakuda ◽  
S. Asahina ◽  
K. Tsutsumi ◽  
M. Shibata ◽  
...  
Keyword(s):  
Surface Structure ◽  
Detection System ◽  
Electron Detection ◽  
Fine Surface

Extended abstract of a paper presented at Microscopy and Microanalysis 2012 in Phoenix, Arizona, USA, July 29 – August 2, 2012.

scholarly journals Structural color for wood coloring: A review

BioResources ◽  
2020 ◽  
Vol 15 (4) ◽  
pp. 9917-9934
Author(s):  
Jing Hu ◽  
Yi Liu ◽  
Zhihui Wu
Keyword(s):  
Surface Structure ◽  
Wood Surface ◽  
Large Scale ◽  
Nanocrystalline Structure ◽  
Light Response ◽  
Structural Color ◽  
Mechanistic Study ◽  
Technology Study ◽  
Surface Color ◽  
Color Film

The color, texture, and natural defects of wood are important factors affecting its commercial value. Change of wood’s surface color is a primary way to improve its value. This study analyzes and summarizes the development status and existing problems of the traditional wood dyeing process and induced discoloration process. It is proposed that color improvement with photonic crystal structure color is a clean and pollution-free ecological biomimetic coloring technology. Its research status in the fields of fiber, fabric, wood, wood-based panel surface color improvement, new coatings for wood, and lignocellulose nanocrystalline structure color film are reviewed. The following aspects were studied: 1) construction and mechanistic study of the wood surface structure color film, 2) light response and interface mechanistic study of the wood surface structure color film, 3) large-scale application technology study of the wood surface biomimetic structure color film, and 4) preparation and functional development of structural color films of lignocellulose nanocrystal.

scholarly journals MAXIMIZING THE VALUE OF PHOTOGRAMMETRIC SURVEYS IN THE CONSERVATION OF WALL PAINTINGS

2021 ◽  
Vol XLVI-M-1-2021 ◽  
pp. 851-857
Author(s):  
L. Wong ◽  
W. Rose ◽  
A. Dhanda ◽  
A. Flavin ◽  
L. Barazzetti ◽  
...  
Keyword(s):  
Spatial Resolution ◽  
Large Scale ◽  
Three Dimensional ◽  
Wall Painting ◽  
Wall Paintings ◽  
Fine Surface ◽  
The Subject ◽  
Three Dimensional Models ◽  
Documentation Tool ◽  
Irregular Topography

Abstract. In the field of wall painting conservation, photogrammetric surveys are an increasingly common documentation tool. The outputs from these surveys, including captured images, orthophotos, and three-dimensional models, are used by conservators to monitor and record condition phenomena and conservation treatments. To serve these conservation needs, the outputs should have visual fidelity, meaning they are a close representation of the subject based on their spatial resolution, overall focus, even lighting and color accuracy. However, wall paintings present unique technical challenges for photogrammetry considering their often large scale, irregular topography, range of surface attributes, and access issues. As a documentation technique more commonly applied to capture the geometry of buildings and objects, using photogrammetry to record both the topography and fine surface details of a wall painting requires thorough planning. This paper examines specific challenges in documenting wall paintings and how collaboration between conservators and heritage-recording specialists has improved practice and maximized the value of photogrammetric surveys for conservation.

Fine surface structure of an intraspinal neurenteric cyst

Neurosurgery ◽  
1990 ◽  
pp. 829 ◽  
Author(s):  
Y Morita ◽  
K Kinoshita ◽  
S Wakisaka ◽  
S Makihara
Keyword(s):  
Surface Structure ◽  
Neurenteric Cyst ◽  
Fine Surface
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