Principal Component Global Analysis of Fluorescence and Absorption Spectra of 2-(2'-Hydroxyphenyl)Benzimidazole

2001 ◽  
Vol 55 (5) ◽  
pp. 630-636 ◽  
Author(s):  
W. Al-Soufi ◽  
M. Novo ◽  
M. Mosquera
Keyword(s):  
Absorption Spectra ◽  
Global Analysis ◽  
Principal Component

Benefits and limits of season-ahead forecasts for hydropower production: a global analysis

2020 ◽  
Author(s):  
Jia Yi Ng ◽  
Donghoon Lee ◽  
Stefano Galelli ◽  
Paul Block
Keyword(s):  
Predictive Accuracy ◽  
Global Analysis ◽  
Principal Component ◽  
Seasonal Forecasts ◽  
Design Specifications ◽  
Reservoir Design ◽  
Hydropower Production ◽  
Flooding Season ◽  
Turbine Capacity ◽  
Effective Use

<p>Season-ahead hydro-climatological forecasts are a useful source of information for hydropower operators: at the onset of a flooding season, for example, predictive information on the timing and magnitude of the inflow volume can help operators schedule the release trajectory, decide on the amount of volume to store, and therefore maximize hydropower production. Intuitively, the forecast value varies not only with predictive accuracy, or skill, but also with the reservoir design specifications. Characterizing and explaining the relationship between skill, design specifications, and value is thus a necessary step towards a more informed and effective use of seasonal forecasts. To investigate the nature of this relationship, we modeled 1,593 hydropower reservoirs, for which we developed 3-month ahead monthly inflow forecasts—based on a principal component linear regression model. Our results show that more than half of the dams could benefit from forecasts, averaging a 6.56% annual increase in hydropower production. We also found that forecast value is largely controlled by reservoir design specifications; specifically, we found that reservoirs with small storage capacity (relative to inflow) and large inflow volumes (relative to turbine capacity) have better chances of benefitting from accurate forecasts. With this information, we classify and map each dam on the basis of its potential to increase hydropower production.</p>

Identification of photofragmentation patterns in trihalide anions by global analysis of vibrational wavepacket dynamics in broadband transient absorption data

2016 ◽  
Vol 18 (48) ◽  
pp. 33287-33302 ◽  
Author(s):  
Sebastian Schott ◽  
Lea Ress ◽  
Jan Hrušák ◽  
Patrick Nuernberger ◽  
Tobias Brixner
Keyword(s):  
Absorption Spectra ◽  
Transient Absorption ◽  
Global Analysis ◽  
Absorption Data ◽  
Transient Absorption Spectra ◽  
Wavepacket Dynamics

Photodissociation pathways of a trihalide series are systematically investigated by globally fitting vibrational wavepacket signals in broadband transient absorption spectra.

Qualitative and Quantitative Analysis of V-Type Amylose-Alcohol Complexes

2011 ◽  
Vol 396-398 ◽  
pp. 1596-1600 ◽  
Author(s):  
Liu Zhi Yang ◽  
Xin Xin Xiao ◽  
Miao Miao Zheng ◽  
Yan Qi Liu
Keyword(s):  
Principal Component Analysis ◽  
Quantitative Analysis ◽  
Absorption Spectra ◽  
Infrared Absorption ◽  
Principal Component ◽  
Qualitative And Quantitative Analysis ◽  
Statistical Software ◽  
Qualitative And Quantitative ◽  
Analysis Calculation ◽  
Infrared Absorption Spectra

In this paper, B-type microcrystalline starch made a combination with ethanol, butanol, hexanol and octanol respectively under certain conditions, a series of V-type amylose-alcohol complexes were prepared. Infrared absorption spectra of obtained Vethanol, Vbutanol, Vhexanol, Voctanol were measured qualitatively to determine the certain alcohol in V-type complexes; Further application of principal component analysis (PCA) with SPSS13.0, DPS7.05 statistical software for analysis calculation of infrared absorption spectra. The result showed that the content of alcohol in Vethanol, Vbutanol, Vhexanol, Voctanol were 19.8%, 14.1%, 9.79% and 8.3%.

scholarly journals The Effects of Steaming on Color and Carotenoid Absorption Spectra of Orange-, Yellow- and Purple-Fleshed Sweet Potatoes (Ipomoea batatas (L.) Lamb.)

2019 ◽  
Vol 1 (2) ◽  
pp. 42
Author(s):  
Maria Ika Putri Soegiarto ◽  
Heriyanto Heriyanto ◽  
Marcelinus A.S. Adhiwibawa ◽  
Endrika Widyastuti ◽  
Widya Dwi Rukmi Putri ◽  
...  
Keyword(s):  
Absorption Spectra ◽  
Spectral Properties ◽  
Ipomoea Batatas ◽  
Bathochromic Shift ◽  
Principal Component ◽  
Carotenoid Content ◽  
Sweet Potatoes ◽  
Carotenoid Absorption ◽  
The Difference ◽  
28 Nm

Sweet potatoes, especially the orange and yellow-fleshed, are functional local food because they contain carotenoids which serve as a pro-vitamin A. The processing of sweet potatoes into noodles, fermented cassava or “tape” and artificial rice is usually prepared through steaming. However, carotenoid is susceptible to degrade when it is subjected to high temperature, such as steaming. The objective of this research is to determine the effects of steaming on the color and carotenoid absorption spectra of local and excellent sweet potatoes which are correlated to the carotenoid content and to evaluate the difference of carotenoid spectral properties among sweet potatoes by principal component analysis (PCA). The steaming treatment decreased color values, such as lightness, redness, and yellowness. In addition, this process also influenced the spectral properties of carotenoid extracts of sweet potatoes. Steaming decreased absorbance and resulted in hypsochromic and bathochromic shifts. Madu Mojokerto, Manohara, local purple fleshed, Beta 1, and Papua Solossa sweet potatoes experienced some decreases in absorbance and a hypsochromic shift of ± 77 % and ± 2 nm, ± 40 % and ± 21 nm, ± 63 % and ± 28 nm, ± 44 % and ± 2 nm, and ± 20 % and ± 23 nm, respectively; while Antin 3 sweet potatoes experienced some decrease in absorbance of ± 36 % and a bathochromic shift of ± 28 nm. The PCA results showed that there were four groups of sweet potatoes based on spectrum shape and absorbance value.

An integration of soil parameters characterizing a Danish agricultural soil

2020 ◽  
Author(s):  
Anne Christine Krull Pedersen ◽  
Vibeke Ernstsen ◽  
Henrik Breuning-Madsen ◽  
Per L. Ambus
Keyword(s):  
Absorption Spectra ◽  
Soil Depth ◽  
Great Influence ◽  
Principal Component ◽  
Soil Samples ◽  
Bulk Soil ◽  
C3 Plants ◽  
Soil Parameters ◽  
C And N ◽  
Insight Into

<p>The complexity and interplay of soil processes are still investigated extensively. Continuous focus on this field of research is important since soil properties such as nitrate reductive capacity has a great influence on groundwater quality. Here, we try to give insight into the dynamics of a vadose zone soil under agricultural management.</p><p>A field of study was selected in Darum in Southwestern Jutland, Denmark. The site is situated in an old periglacial terrain on meltwater-deposited sand. The field has been under maize (<em>Zea mays</em>) monoculture for the past 20 years. Prior to this period it had been kept with C3 plants only.  Soil sampling was accomplished in three replicates of 1.6 m.</p><p>The bulk soil samples were analyzed for total C and N, δ<sup>13</sup>C and δ<sup>15</sup>N. Dissolved organic matter (DOM) and NO<sub>3</sub><sup>-</sup> were recovered from cold-water extractions of the soil samples. Extractions were analyzed for their UV-Vis absorption spectra.</p><p>Incubation experiments were performed on bulk soil portions in order to assay the activity and isotopic imprint CO<sub>2</sub> respiration. The soil were also incubated under anoxic conditions with substrate amendments (KNO<sub>3</sub> and C additions). The resulting N<sub>2</sub>O releases were assigned to biologically driven nitrate reduction. Ultimately, principal component analyses (PCA) were carried out on the results.</p><p>The C and N concentrations were highest in the Ap horizon and decreased with soil depth. The respiratory and nitrate reductive capacity also declined with depth, but were evident in all of the analyzed soil depths. All individual depths responded statistically significant to substrate addition by increase in the N<sub>2</sub>O production.</p><p>The isotopic results showed that the main pool of maize-derived C were also found in the plough layer. However, the respiratory isotopic results evidenced the presence of C4 plant derived C throughout the soil profile, after 20 years of monoculture.</p><p>The UV-Vis absorption spectra gave insight into the quality of the DOM pools. The parameter E253/E203 is associated with functional groups on aromatic rings and increases with composting time. The soil had an overall increase in this parameter with depth. The integrated magnitude of distinct wavelengths (270-300 nm, 300-380 nm and 380-500 nm) is an index of protein-, fulvic-, and humic like substances. Surprisingly, no substantial discrepancies in the distribution between these pools was found with depth. However, the overall pattern was declining steeply with soil depth, emphasizing the importance of dilution when assessing DOM availability and quality.</p><p>The PCA could explain >55 % of the variance by the first principal component. The PCA showed that the C and N concentrations were positively correlated. Alongside were the ambient N<sub>2</sub>O activity to the indexes of protein-, fulvic and humic like substances. The inherent NO<sub>3</sub><sup>-</sup> concentration, the N<sub>2</sub>O activity (KNO<sub>3</sub> amended) and the respiratory CO<sub>2</sub> production were also positively correlated – however negatively correlated with the E253/E203 parameter. <br>Therefore, respiratory and nitrate reductive capacities of the Darum soil, depends notably on the presence of less degraded DOM, on the concentration of protein-, fulvic and humic like substances, and finally on the inherent soil NO<sub>3</sub><sup>-</sup> concentration.</p>

Wavelet based de-noising of breath air absorption spectra profiles for improved classification by principal component analysis

2015 ◽  
Author(s):  
Yu. V. Kistenev ◽  
A. V. Shapovalov ◽  
A. V. Borisov ◽  
D. A. Vrazhnov ◽  
V. V. Nikolaev ◽  
...  
Keyword(s):  
Principal Component Analysis ◽  
Absorption Spectra ◽  
Principal Component ◽  
Component Analysis

Applications of principal component analysis to breath air absorption spectra profiles classification

2015 ◽  
Author(s):  
Yu. V. Kistenev ◽  
A. V. Shapovalov ◽  
A. V. Borisov ◽  
D. A. Vrazhnov ◽  
V. V. Nikolaev ◽  
...  
Keyword(s):  
Principal Component Analysis ◽  
Absorption Spectra ◽  
Principal Component ◽  
Component Analysis
Sign in / Sign up

Export Citation Format

Share Document