Determination of the carbonyl index of polyethylene and polypropylene using specified area under band methodology with ATR-FTIR spectroscopy

AbstractThe current measurement techniques described in the literature for the determination of the carbonyl index (CI) for polyolefins such as polyethylene and polypropylene were compared and contrasted. These were all found to be inconsistent or inaccurate and were not capable of differentiating significant changes in carbonyl peak evolution throughout accelerated ageing. As a consequence of these findings, a methodology, specified area under band (SAUB) is presented here to more accurately represent the CI as a general means of reporting. The increased precision in the methodology is explained and compared to other methodologies for determining CI. The SAUB method is also shown to be capable of elucidating the differences in relative extent and rates of CI for different polyolefins, exposed to the same conditions over the same time period.

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ChemInform Abstract: Reaction of the NO3Radical with CO: Determination of an Upper Limit for the Rate Constant Using FTIR Spectroscopy.

Chemischer Informationsdienst ◽

10.1002/chin.198644022 ◽

1986 ◽

Vol 17 (44) ◽

Author(s):

J. HJORTH ◽

G. OTTOBRINI ◽

G. RESTELLI

Keyword(s):

Ftir Spectroscopy ◽

Rate Constant ◽

Upper Limit

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Modeling Population Spatial-Temporal Distribution Using Taxis Origin and Destination Data

Sustainability ◽

10.3390/su13073727 ◽

2021 ◽

Vol 13 (7) ◽

pp. 3727

Author(s):

Fatema Rahimi ◽

Abolghasem Sadeghi-Niaraki ◽

Mostafa Ghodousi ◽

Soo-Mi Choi

Keyword(s):

Regression Analysis ◽

Mean Squared Error ◽

Population Distribution ◽

Temporal Distribution ◽

Coefficient Of Determination ◽

Temporal Modeling ◽

Location Data ◽

Time Period ◽

Proposed Model

During dangerous circumstances, knowledge about population distribution is essential for urban infrastructure architecture, policy-making, and urban planning with the best Spatial-temporal resolution. The spatial-temporal modeling of the population distribution of the case study was investigated in the present study. In this regard, the number of generated trips and absorbed trips using the taxis pick-up and drop-off location data was calculated first, and the census population was then allocated to each neighborhood. Finally, the Spatial-temporal distribution of the population was calculated using the developed model. In order to evaluate the model, a regression analysis between the census population and the predicted population for the time period between 21:00 to 23:00 was used. Based on the calculation of the number of generated and the absorbed trips, it showed a different spatial distribution for different hours in one day. The spatial pattern of the population distribution during the day was different from the population distribution during the night. The coefficient of determination of the regression analysis for the model (R2) was 0.9998, and the mean squared error was 10.78. The regression analysis showed that the model works well for the nighttime population at the neighborhood level, so the proposed model will be suitable for the day time population.

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A novel approach for the discrimination of culture medium from Vascular Endothelial Growth Factor (VEGF) overexpressing colorectal cancer cells

Turkish Journal of Biochemistry ◽

10.1515/tjb-2020-0058 ◽

2020 ◽

Vol 0 (0) ◽

Cited By ~ 1

Author(s):

Sinem Tunçer ◽

Rafig Gurbanov

Keyword(s):

Colorectal Cancer ◽

Vascular Endothelial Growth Factor ◽

Growth Factor ◽

Ftir Spectroscopy ◽

Cancer Cells ◽

Lower Amount ◽

Vascular Endothelial ◽

Colorectal Cancer Cells ◽

Endothelial Growth Factor

AbstractObjectivesThe expression level of Vascular Endothelial Growth Factor (VEGF) is assumed as a prognostic marker for several tumor types, including colorectal cancer. Therefore, the determination of pre- and post-therapy levels of VEGF appears to have great value in the assessment of tumor prognosis. Enzyme-Linked Immunosorbent Assay (ELISA) is commonly used for the determination of serum or plasma VEGF levels, but the method is costly and time-consuming. In this study, we aimed to describe a rapid and cost-effective analysis method to discriminate VEGF overexpressing colorectal cancer-derived conditioned medium (CM).MethodsAttenuated Total Reflection (ATR)-Fourier Transform Infrared (FTIR) spectroscopy, combined with Principal Component Analysis (PCA) and Linear Discriminant Analysis (LDA), was used to differentiate VEGF overexpressing colorectal cancer cell line CM from CM obtained from the corresponding control cells which express and secrete relatively lower amount of VEGF.ResultsSamples belong to VEGF overexpressing colorectal cancer cells were clearly distinguished from the control group with very high PC scores as PC1 + PC2 = 96%. Besides, a 100% accurate distinction between these two groups was achieved by the LDA analysis.ConclusionsATR-FTIR spectroscopy combined with pattern recognition techniques was able to discriminate CM of VEGF overexpressing colorectal cancer cells with high efficiency and accuracy.

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Raman Sensor for the Determination of Gas Solubility

Physchem ◽

10.3390/physchem1020012 ◽

2021 ◽

Vol 1 (2) ◽

pp. 176-188

Author(s):

Gregor Lipinski ◽

Markus Richter

Keyword(s):

Carbon Dioxide ◽

Gas Separation ◽

Accurate Determination ◽

Measurement Techniques ◽

Screening Tools ◽

Measuring System ◽

Separation Processes ◽

Use Of Resources ◽

Gas Solubilities

Efficient and environmentally responsible use of resources requires the development and optimization of gas separation processes. A promising approach is the use of liquids that are designed for specific tasks, e.g., the capture of carbon dioxide or other greenhouse gases. This requires an accurate determination of gas solubilities for a broad range of temperatures and pressures. However, state of the art measurement techniques are often very time consuming or exhibit other pitfalls that prevent their use as efficient screening tools. Here, we show that the application of Raman spectroscopy through a compact measuring system can simplify data acquisition for the determination of gas solubilities in liquids. To demonstrate that this approach is expedient, we determined gas solubilities of carbon dioxide in water for three isotherms T = (288.15, 293.15, 298.15) K over a pressure range from p = (0.5–5) MPa and in three imidazolium-based ionic liquids for one isotherm T = 298.15 K at pressures from p = (0.1–5) MPa. When compared to data in the literature, all results are within the reported uncertainties of the measurement techniques involved. The developed analysis method eliminates the need for a lengthy volume or mass calibration of the sample prior to the measurements and, therefore, allows for fast screening of samples, which can help to advance gas separation processes in scientific and industrial applications.

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Precise determination of the power transmission coefficient of low-loss passive linear two-ports by RF noise power and RF attenuation measurement techniques

Proceedings of Conference on Precision Electromagnetic Measurements Digest ◽

10.1109/cpem.1994.333207 ◽

2002 ◽

Author(s):

F.-I. Buchholz ◽

D. Schubert ◽

D. Stumpe

Keyword(s):

Transmission Coefficient ◽

Power Transmission ◽

Measurement Techniques ◽

Precise Determination ◽

Noise Power ◽

Low Loss ◽

Attenuation Measurement ◽

Power Transmission Coefficient ◽

Rf Noise

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Highly stabilized flexible transparent capacitive photodetector based on silver nanowire/graphene hybrid electrodes

Scientific Reports ◽

10.1038/s41598-021-88730-6 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Yooji Hwang ◽

Young Hyun Hwang ◽

Kwang Wook Choi ◽

Seungwon Lee ◽

Soojin Kim ◽

...

Keyword(s):

Sheet Resistance ◽

Dielectric Layer ◽

Measurement Techniques ◽

Current Measurement ◽

Silver Nanowire ◽

Semiconductor Materials ◽

Graphene Electrode ◽

Mechanical Durability ◽

New Type ◽

Ag Nanowire

AbstractThe need for photodetectors in various fields has gradually emerged, and several studies in this area are therefore being conducted. For photodetectors to be used in various environments, their transparency, flexibility, and durability must be ensured. However, the development of flexible photodetectors based on the current measurement techniques of conventional photodetectors has been difficult owing to the limitations of semiconductor materials. In this study, a new type of flexible and transparent capacitive photodetector was fabricated to address the shortcomings of conventional photodetectors. In addition, by introducing graphene electrodes to a new type of manufactured photodetector, devices with excellent overall chemical, thermal, and mechanical durability have been developed. Compared to photodetectors based on pristine Ag nanowire (AgNW) electrodes, AgNW/graphene hybrid electrode-based photodetectors exhibit a 20% higher photosensitivity. Also, the hybrid AgNW/graphene electrode on the dielectric layer exhibited low sheet resistance (~ 8 Ω/sq) and relatively high transmittance (~ 45%).

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Determination of trans Fat in Selected Fast Food Products and Hydrogenated Fats of India Using Attenuated Total Reflection Fourier Transform Infrared (ATR-FTIR) Spectroscopy

Journal of Oleo Science ◽

10.5650/jos.ess16168 ◽

2017 ◽

Vol 66 (3) ◽

pp. 251-257 ◽

Cited By ~ 3

Author(s):

Mohd Umar Khan ◽

Mohammad Fahimul Hassan ◽

Abdul Rauf

Keyword(s):

Fourier Transform ◽

Ftir Spectroscopy ◽

Fast Food ◽

Fourier Transform Infrared ◽

Food Products ◽

Total Reflection ◽

Attenuated Total Reflection ◽

Hydrogenated Fats

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Determination of Total Polar Compounds in Frying Oils by PE-Film-Based FTIR and ATR-FTIR Spectroscopy

European Journal of Lipid Science and Technology ◽

10.1002/ejlt.201800250 ◽

2018 ◽

Vol 120 (12) ◽

pp. 1800250 ◽

Cited By ~ 5

Author(s):

Jia Chen ◽

Leshan Zhang ◽

Qiaona Geng ◽

Bingyu Jing ◽

Xiuzhu Yu

Keyword(s):

Ftir Spectroscopy ◽

Polar Compounds ◽

Total Polar Compounds ◽

Frying Oils

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Evaluation of an Alternative Staining Method Using SYTO 13 to Determine Reticulated Platelets

Thrombosis and Haemostasis ◽

10.1055/s-0039-1681101 ◽

2019 ◽

Vol 119 (05) ◽

pp. 779-785 ◽

Cited By ~ 6

Author(s):

Laura Hille ◽

Marco Cederqvist ◽

Julia Hromek ◽

Christian Stratz ◽

Dietmar Trenk ◽

...

Keyword(s):

Flow Cytometry ◽

Platelet Reactivity ◽

Dependent Manner ◽

Reticulated Platelets ◽

Automated Assay ◽

Rna Quantification ◽

Time Period ◽

Immature Platelet Fraction ◽

Syto 13

AbstractReticulated platelets reflect the rate of platelet turnover and represent the youngest circulating platelets in peripheral blood. Reticulated platelets contain residual ribonucleic acid (RNA) from megakaryocytes which is lost in a time-dependent manner and can be transcribed into proteins even in the absence of a nucleus. An increased proportion of reticulated platelets is associated with higher platelet reactivity, cardiovascular events and mortality. At present, a fully automated assay system (SYSMEX haematology analyser) is available for analysis. This method, however, is not suitable for extended laboratory investigations like subsequent cell sorting. Flow cytometry analysis after staining with thiazole orange (TO) is frequently used in such settings despite several limitations. Here, we describe a new assay for determination of reticulated platelets by flow cytometry using the nucleic acid staining dye SYTO 13 and compare it with SYSMEX and TO staining as current standards. A significant correlation between immature platelet fraction (IPF) determined by SYSMEX XE-2100 analyser and results obtained with the SYTO 13-based assay was observed (r = 0.668, p < 0.001) which was stable during a reasonable time period. In contrast, the correlation between TO staining and IPF was weaker (r = 0.478, p = 0.029) and lost after 90 minutes of staining. SYTO 13 staining of platelets enabled sorting of RNAlow and RNArich platelets which was confirmed by RNA quantification of sorted platelets. Except for fixation of platelets, sorting of these platelet sub-populations was stable under various experimental settings. In summary, determination of reticulated platelets with the new SYTO 13 assay offers distinct technical advantages enabling further laboratory processing.

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