scholarly journals Using light intensity to control reaction kinetics and reversibility in photomechanical crystals

2020 ◽  
Vol 11 (36) ◽  
pp. 9852-9862 ◽  
Author(s):  
Connor J. Easley ◽  
Fei Tong ◽  
Xinning Dong ◽  
Rabih O. Al-Kaysi ◽  
Christopher J. Bardeen
Keyword(s):  
Light Intensity ◽  
Reaction Kinetics ◽  
Recovery Rates ◽  
Control Reaction ◽  
Mechanical Recovery

The chemical and mechanical recovery rates of crystalline 4-fluoro-9-anthracenecarboxylic acid, a thermally reversible photomechanical material, can be controlled by both the intensity of the photodimerization pulse and the use of a weak hold beam.

scholarly journals Modulating Flow Topology in Microdroplets to Control Reaction Kinetics

2021 ◽  
Vol 5 (2) ◽  
pp. 2000309
Author(s):  
Shaohua Ma ◽  
Haoran Zhao ◽  
Edgar A. Galan ◽  
Stavroula Balabani
Keyword(s):  
Reaction Kinetics ◽  
Flow Topology ◽  
Control Reaction

scholarly journals Response Options for an Offshore Deepwater Blow-Out, A Generic Evaluation of Individual and Combined Response Strategies

2021 ◽  
Vol 2021 (1) ◽  
Author(s):  
Per Johan Brandvik ◽  
Jørgen Skancke ◽  
Ragnhild Daae ◽  
Kristin Sørheim ◽  
Per S. Daling ◽  
...  
Keyword(s):  
Oil Spill ◽  
Oil Recovery ◽  
Performance Testing ◽  
Similar Amount ◽  
Recovery Rates ◽  
Response Options ◽  
Modelling Studies ◽  
Oil Spill Response ◽  
Different Response ◽  
Mechanical Recovery

Abstract The low oil recovery rates reported during Macondo (3–5% of the released oil) have caused discussions regarding the efficiency of mechanical recovery compared to other oil spill response options. These low recovery rates have unfortunately been used as reference recovery rates in several later modelling studies and oil spill response analysis. Multiple factors could explain these low rates, such as operational priorities, where dispersants and/or in situ burning are given priority before mechanical recovery; extended safety zones; availability of adequate equipment and storage capacity of collected oil; the number of units available; the level of training and the available remote sensing support to guide operations. This study uses the OSCAR oil spill model to simulate a deep-water oil release to evaluate the effect of different response options both separately and in combination. The evaluated response options are subsea dispersant injection, mechanical recovery, and a combination of these. As expected, Subsea Dispersant Injection (SSDI) was highly effective and resulted in a significant reduction in residual surface oil (8% of released oil volume, versus 28% for the non-response option, NR). However, using large offshore oil recovery systems also reduced residual surface oil with a similar amount (9% of released oil volume). These results deviate significantly from the efficiency numbers reported after the Macondo incident and from later modelling studies scaled after the Macondo recovery rates. The increased efficiency of mechanical reported in this study is mainly due to inclusion of updated descriptions of response capabilities, reduced exclusion zone, a more realistic representation of surface oil distribution and modelling of response units' interactions with oil, (efficient oil recovery only on thick parts of the oil slick). The response capabilities and efficiency numbers for the different response options used in this study are based on equipment specifications from multiple response providers and authorities (Norwegian Clean Seas organisation (NOFO), Oil Spill Response (OSRL), Norwegian Coastal Administration (NCA), US Bureau of Safety and Environmental Enforcement (BSEE) and others). These capabilities are justified by well-established contingency plans, offshore exercises and annual equipment performance testing with oil.

scholarly journals Reaction Kinetics: Modulating Flow Topology in Microdroplets to Control Reaction Kinetics (Adv. Biology 2/2021)

2021 ◽  
Vol 5 (2) ◽  
pp. 2170023
Author(s):  
Shaohua Ma ◽  
Haoran Zhao ◽  
Edgar A. Galan ◽  
Stavroula Balabani
Keyword(s):  
Reaction Kinetics ◽  
Flow Topology ◽  
Control Reaction

Fine structure of the retina of the giant scallop, Placopecten magellanicus

1984 ◽  
Vol 42 ◽  
pp. 312-313
Author(s):  
C.V.L. Powell
Keyword(s):  
Fine Structure ◽  
Electron Microscope ◽  
Light Intensity ◽  
Scanning Electron Microscope ◽  
Eye Development ◽  
Preliminary Observation ◽  
Columnar Epithelium ◽  
Placopecten Magellanicus ◽  
Environmental Light ◽  
Scanning Electron

The overall fine structure of the eye in Placopecten is similar to that of other scallops. The optic tentacle consists of an outer columnar epithelium which is modified into a pigmented iris and a cornea (Fig. 1). This capsule encloses the cellular lens, retina, reflecting argentea and the pigmented tapetum. The retina is divided into two parts (Fig. 2). The distal retina functions in the detection of movement and the proximal retina monitors environmental light intensity. The purpose of the present study is to describe the ultrastructure of the retina as a preliminary observation on eye development. This is also the first known presentation of scanning electron microscope studies of the eye of the scallop.

Effect of light intensity on the ultrastructure of the filamentous cyanobacterium, Anabaena variabilis

1988 ◽  
Vol 46 ◽  
pp. 300-301
Author(s):  
C. S. Bricker ◽  
S. R. Barnum ◽  
B. Huang ◽  
J. G. Jaworskl
Keyword(s):  
Fatty Acid ◽  
Light Intensity ◽  
Acid Content ◽  
Fatty Acid Content ◽  
Anabaena Variabilis ◽  
Chloroplast Envelope ◽  
Major Constituent ◽  
Filamentous Cyanobacterium ◽  
Photosynthetic Membrane ◽  
Effect Of Light

Cyanobacteria are Gram negative prokaryotes that are capable of oxygenic photosynthesis. Although there are many similarities between eukaryotes and cyanobacteria in electron transfer and phosphorylation during photosynthesis, there are two features of the photosynthetic apparatus in cyanobacteria which distinguishes them from plants. Cyanobacteria contain phycobiliproteins organized in phycobilisomes on the surface of photosynthetic membrane. Another difference is in the organization of the photosynthetic membranes. Instead of stacked thylakolds within a chloroplast envelope membrane, as seen In eukaryotes, IntracytopIasmlc membranes generally are arranged in three to six concentric layers. Environmental factors such as temperature, nutrition and light fluency can significantly affect the physiology and morphology of cells. The effect of light Intensity shifts on the ultrastructure of Internal membrane in Anabaena variabilis grown under controlled environmental conditions was examined. Since a major constituent of cyanobacterial thylakolds are lipids, the fatty acid content also was measured and correlated with uItrastructural changes. The regulation of fatty acid synthesis in cyanobacteria ultimately can be studied if the fatty acid content can be manipulated.

Inter-Method Reliability of Pulse Volume Related Measures Derived Using Finger-Photoplethysmography

2018 ◽  
Vol 32 (4) ◽  
pp. 182-190 ◽  
Author(s):  
Kenta Matsumura ◽  
Koichi Shimizu ◽  
Peter Rolfe ◽  
Masanori Kakimoto ◽  
Takehiro Yamakoshi
Keyword(s):  
Light Intensity ◽  
Adverse Effects ◽  
Light Source ◽  
Direct Current ◽  
Resting State ◽  
Current Component ◽  
Psychophysiological Measures ◽  
Pulse Volume ◽  
Optical Paths ◽  
Sensor Positions

Abstract. Pulse volume (PV) and its related measures, such as modified normalized pulse volume (mNPV), direct-current component (DC), and pulse rate (PR), derived from the finger-photoplethysmogram (FPPG), are useful psychophysiological measures. Although considerable uncertainties exist in finger-photoplethysmography, little is known about the extent of the adverse effects on the measures. In this study, we therefore examined the inter-method reliability of each index across sensor positions and light intensities, which are major disturbance factors of FPPG. From the tips of the index fingers of 12 participants in a resting state, three simultaneous FPPGs having overlapping optical paths were recorded, with their light intensity being changed in three steps. The analysis revealed that the minimum values of three coefficients of Cronbach’s α for ln PV, ln mNPV, ln DC, and PR across positions were .948, .850, .922, and 1.000, respectively, and that those across intensities were .774, .985, .485, and .998, respectively. These findings suggest that ln mNPV and PR can be used for psychophysiological studies irrespective of minor differences in sensor attachment positions and light source intensity, whereas and ln DC can also be used for such studies but under the condition of light intensity being fixed.

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