Damp Heat Aging Behavior of a Polyamide-Based Backsheet for Photovoltaic Modules

2016 ◽  
Vol 138 (4) ◽  
Author(s):  
Klaus J. Geretschläger ◽  
Gernot M. Wallner ◽  
Ingrid Hintersteiner ◽  
Wolfgang Buchberger
Keyword(s):  
High Performance ◽  
Near Infrared ◽  
Heat Exposure ◽  
Accelerated Aging ◽  
Nir Spectroscopy ◽  
Attenuated Total Reflection ◽  
Gravimetric Analysis ◽  
Scanning Calorimetry ◽  
Premature Failure ◽  
Mechanical Methods

This paper describes and evaluates accelerated aging of a titanium dioxide (TiO2) filled polyamide (PA) based backsheet film for photovoltaic (PV) modules. Damp heat exposure (85%RH, 85 °C) was carried out up to 2000 hrs. The backsheet was characterized using microscopic, spectroscopic, thermoanalytic, chromatographic, and mechanical methods. While Raman microscopy, infrared spectroscopy in attenuated total reflection mode (IR-ATR), scanning calorimetry (DSC), and thermal gravimetric analysis did not reveal aging-induced changes, significant yellowing was detected by ultraviolet visible near infrared (UV/VIS/NIR) spectroscopy. Depending on the stabilizer type (UV-absorbers, hindered amine light stabilizers (HALSs), and antioxidants), rather different consumption rates were ascertained by high-performance liquid chromatography (HPLC) and gas chromatography (GC). Although the ultimate mechanical properties decreased significantly, no full embrittlement was obtained after damp heat exposure of up to 2000 hrs. The observed physical and chemical aging mechanisms were classified as within the induction period without premature failure.

Synthesis of Amino-Functionalized Graphene Oxide/Azobenzene Polyimide and its Simulation of Optical Switches

2017 ◽  
Vol 231 (11-12) ◽  
Author(s):  
Tianlin Cao ◽  
Fanyu Zhao ◽  
Zulin Da ◽  
Fengxian Qiu ◽  
Dongya Yang ◽  
...  
Keyword(s):  
Graphene Oxide ◽  
Near Infrared ◽  
Optical Switches ◽  
Attenuated Total Reflection ◽  
Functionalized Graphene ◽  
Visible Spectroscopy ◽  
Scanning Calorimetry ◽  
Functionalized Graphene Oxide ◽  
Uv Visible ◽  
532 Nm

AbstractIn this work, an amino-functionalized graphene oxide (AFGO) was synthesized by graphene oxide (GO) and ethylene diamine. A novel amino-functionalized graphene oxide/azobenzene polyimide (AFGO/ACPI) was synthesized with AFGO, azobenzene chromophore and pyromellitic dianhydride (PMDA). The structure, mechanical and thermal property of AFGO/ACPI were characterized and measured by fourier transform infrared, UV-visible spectroscopy, near-infrared spectrum, thermogravimetric analysis and differential scanning calorimetry. To obtain the refractive index of AFGO/ACPI at different temperature and wavelength (532 nm, 650 nm and 850 nm), the attenuated total reflection (ATR) method was used to measure, and thermo optic coefficients (dn/dT) were −7.22×10

Focusing near Infrared Spectroscopy on the Business Objectives of Modern Pharmaceutical Production

1998 ◽  
Vol 6 (A) ◽  
pp. A13-A19 ◽  
Author(s):  
T.G. Axon ◽  
R. Brown ◽  
S.V. Hammond ◽  
S.J. Maris ◽  
F. Ting
Keyword(s):  
High Performance ◽  
Near Infrared ◽  
Real Life ◽  
Nir Spectroscopy ◽  
Raw Material ◽  
Develop Model ◽  
Data Sets ◽  
Total Quality ◽  
Model Free ◽  
Pharmaceutical Production

The early use of near infrared (NIR) spectroscopy in the pharmaceutical industry was for raw material identification, later moving on to some conventional “calibrations” for various ingredients in a variety of sample types. The approach throughout this development process has always been “conventional” with one measurement by NIR directly replacing some other slower method, be it Mid-IR identification, or determinations by Karl Fischer, high performance liquid chromatography (HPLC)etc. A significant change in approach was demonstrated by Plugge and Van der Vlies1 in 1993, where a qualitative system was used to provide “quantitative like” answers for potency of a drug substance. Following on from that key paper, there has been a realisation that the qualitative analysis ability of NIR, has the potential to be a powerful tool for process investigation, control and validation. The final step has been to develop “model free” approaches, that consider individual data sets as unique systems, and present the opportunity for NIR to escape the shackles of “calibration” in one form or another. The use of qualitative, or model free, approaches to NIR spectroscopy provides an effective tool for satisfying many of the demands of modern pharmaceutical production. “Straight through production,” “right first time,” “short cycle time” and “total quality management” philosophies can be realised. Eventually the prospect of parametric release may be materialised with a strong contribution from NIR spectroscopy. This paper will illustrate the above points with some real life examles.

scholarly journals Discrimination of Salvia miltiorrhiza Bunge from Different Geographical Locations Employing High-Performance Liquid Chromatography, Near-Infrared Fingerprinting Combined with Chemometrics

2020 ◽  
Vol 2020 ◽  
pp. 1-13
Author(s):  
Jiao Wang ◽  
Yichun Sun ◽  
Zhan Li ◽  
Wei Li ◽  
Yuanyuan Pang ◽  
...  
Keyword(s):  
High Performance Liquid Chromatography ◽  
Liquid Chromatography ◽  
Discriminant Analysis ◽  
High Performance ◽  
Near Infrared ◽  
Salvia Miltiorrhiza ◽  
Nir Spectroscopy ◽  
Gradient Elution ◽  
Array Detector ◽  
Geographical Locations

To evaluate the quality of Salvia miltiorrhiza Bunge, high-performance liquid chromatography-diode array detector (HPLC/UV-PAD), near infrared (NIR) spectroscopy, and chemometrics were used to discriminate nine components of samples from four different geographical locations. HPLC was performed with a C18 (5 μm, 4.6 mm × 250 mm) column and 0.1% formic acid aqueous solution-acetonitrile with a gradient elution system. Orthogonal partial least squares discriminant analysis was used to identify the amounts of salvianolic acid B. NIR was used to distinguish rapidly S. miltiorrhiza Bunge samples from different geographical locations. In this assay, discriminant analysis was performed, and the accuracy was found to be 100%. The combination of these two methods can be used to quickly and accurately identify S. miltiorrhiza Bunge from different geographical locations.

scholarly journals Characterization of herbal powder blends homogeneity using near-infrared spectroscopy

2014 ◽  
Vol 07 (06) ◽  
pp. 1450004 ◽  
Author(s):  
Wenlong Li ◽  
Haibin Qu
Keyword(s):  
High Performance ◽  
Near Infrared ◽  
Fiber Optic ◽  
Nir Spectroscopy ◽  
Fiber Optic Probe ◽  
Liquid Chromatograph ◽  
Noninvasive Technique ◽  
Correlation Spectrum ◽  
Blending Process ◽  
Optic Probe

Homogeneity of powder blend is essential to obtain uniform contents for the tablets and capsules. Near-infrared (NIR) spectroscopy with fiber-optic probe was used as an on-line technique for monitoring the homogeneity of pharmaceutical blend during the blending process instead of the traditional techniques, such as high performance liquid chromatograph (HPLC) method. In this paper NIRS with a SabIR diffuse reflectance fiber-optic probe was used to monitor the blending process of coptis powder and lactose (excipient) with different contents, and further qualitative methods, like similarity, moving block of standard deviation and mean square were used for calculation purposes with the collected spectra after the pretreatment of multiplicative signal correction (MSC) and second derivative. Correlation spectrum was used for the wavelength selection. Four different coptis were blended with lactose separately to validate the proposed method, and the blending process of "liu wei di huang" pill was also simulated in bottles to verify this method on multiple herbal blends. The overall results suggest that NIRS is a simple, effective and noninvasive technique can be successfully applied to the determination of homogeneity in the herbal blend.

Freshness Evaluation in Chub Mackerel (Scomber japonicus) Using Near-Infrared Spectroscopy Determination of the Cadaverine Content

2019 ◽  
Vol 82 (5) ◽  
pp. 768-774 ◽  
Author(s):  
KILBO SHIM ◽  
YEONGYEOM JEONG
Keyword(s):  
Nitrogen Content ◽  
Biogenic Amine ◽  
High Performance ◽  
Near Infrared ◽  
Nir Spectroscopy ◽  
Viable Cell ◽  
High Water Content ◽  
Scomber Japonicus ◽  
Chub Mackerel ◽  
Basic Nitrogen

ABSTRACT We analyzed the volatile basic nitrogen content, pH, total viable cell count, and biogenic amine contents in chub mackerel (Scomber japonicus) stored at 5 and 25°C to examine changes in freshness. Among the various parameters, we found the volatile basic nitrogen content had the highest correlation with cadaverine content (r2 = 0.72 to 0.88). We also tried to measure cadaverine contents at different times during storage by using near-infrared (NIR) spectroscopy. However, because of the high water content in the fish, we could not obtain meaningful results. Next, we prepared samples for NIR spectroscopy by dilution with 0.1 N HCl, ultrafiltration (3 or 10 kDa) with a glass filter, and dehydration. The samples prepared with the 3-kDa filter had peaks in the NIR spectra between 1,379.3 and 1,388.9 nm, and those prepared with the 10-kDa filter had peaks in the spectra between 1,897.3 and 1,898.6 nm. The correlation coefficient (r2) between the NIR spectroscopy and high-performance liquid chromatography with cadaverine results was 0.98 to 0.99. We concluded that the biogenic amine content could be used to evaluate freshness in fish products, and that NIR measurements could be used to rapidly and accurately determine freshness.

scholarly journals Effect of High Temperature Sodium Hydroxide Immersion on Fusion Bond Epoxy Coating

2015 ◽  
Vol 2015 ◽  
pp. 1-7 ◽  
Author(s):  
Amal Al-Borno ◽  
Xianyi Chen ◽  
Shailesh Kewaldas Dhoke
Keyword(s):  
Sodium Hydroxide ◽  
Electrochemical Impedance ◽  
Analytical Techniques ◽  
Attenuated Total Reflection ◽  
Low Molecular Weight ◽  
Scanning Calorimetry ◽  
Premature Failure ◽  
X Ray ◽  
Deposit Layer

Fusion Bond Epoxy (FBE) coating system was exposed to 5% sodium hydroxide at elevated temperature for 30 days. The result of exposure showed formation of adhere deposit layer, a discolored zone underneath and remaining un-affected bulk of the coating. The deterioration of the coating was characterized using analytical techniques like scanning electron microscopy (SEM), energy-dispersive X-ray (EDAX) spectroscopy, attenuated total reflection-Fourier transform infrared spectroscopy (ATR-FTIR), differential scanning calorimetry (DSC), pull-off adhesion, and electrochemical impedance spectroscopy (EIS). Results obtained indicated chemical deterioration of the coating in the discolored zone and leaching of low molecular weight coating component forming deposit layer. Although the adhesion strength and barrier property were not affected, the polymer matrix in the affected zone undergoes severe changes in its surface microstructure, primary chemical structure, and glass transition temperature. This may inflict serious impairment of the coating functional properties and premature failure of the coating in long term exposure.

Monitoring the Chemistry and Monosaccharide Ratio of Eucalyptus Dunnii Wood by near Infrared Spectroscopy

2016 ◽  
Vol 24 (6) ◽  
pp. 537-548 ◽  
Author(s):  
Chengfeng Zhou ◽  
Wei Jiang ◽  
Brian K. Via ◽  
P.M. Chetty ◽  
Tammy Swain
Keyword(s):  
High Performance ◽  
Near Infrared ◽  
Multivariate Calibration ◽  
Nir Spectroscopy ◽  
Forest Products ◽  
Chemical Components ◽  
Least Squares Regression ◽  
Near Infrared Reflectance ◽  
Wet Chemistry ◽  
Eucalyptus Dunnii

Determination of wood chemical components such as extrac tives, lignin and car bohydrate content by conventional wet chemistry is time consuming and sometimes hazardous. Near infrared reflectance (NIR) spectroscopy coupled with multivariate calibration was utilised to offer a fast alternative to wet chemistry methods. In this study, 70 Eucalyptus dunnii wood samples were collected to investigate the correlation and modelling potential of using NIR spectra to predict extractives, lignin, carbohydrate content and ash which were determined with classical methods (extractives, ash and lignin) and high-performance liquid chromatography (sugars). Partial least squares regression was used for multivariate calibration. An evaluation of the results found that ash, extractives and lignin could be predicted with the strongest prediction diagnostics while mannose and glucose-to-mannose ratio models exhibited the lowest performance. The robust ability to predict glucose-to-xylose ratio ( r2 = 0.87) provided a unique way to utilise NIR to monitor biomass quality and could be helpful for the improvement of ethanol and other forest products. The large range in glucose-to-xylose ratio (2.0 to 4.0), as determined through NIR, suggests that using xylose content to estimate total hemicellulose content may be unsuitable, though this type of ratio assumption and analysis is common for softwoods.

Effect of polyarylene ether nitrile on the curing behaviors and properties of bisphthalonitrile

2016 ◽  
Vol 23 (6) ◽  
pp. 579-588
Author(s):  
Zhiran Chen ◽  
Yajie Lei ◽  
Hailong Tang ◽  
Xiaobo Liu
Keyword(s):  
High Performance ◽  
Polymer Networks ◽  
Polymeric Materials ◽  
Interpenetrating Polymer Networks ◽  
Polymerization Reaction ◽  
Gravimetric Analysis ◽  
Scanning Calorimetry ◽  
Thermal Stabilities ◽  
Polyarylene Ether Nitrile ◽  
Heat Polymerization

AbstractThe 2,2-bis[4-(3,4)-dicyanophenoxy phenyl]propane (BAPh)/polyarylene ether nitrile (PEN-OH) prepolymers and polymers were prepared by heat polymerization. Firstly, BAPh/PEN-OH systems were characterized using differential scanning calorimetry, dynamic rheological analysis, and thermal gravimetric analysis. The results revealed that the polymerization reaction can be controlled by various concentrations of PEN-OH and postcuring temperatures, and BAPh/PEN-OH prepolymers had low curing temperatures (229.3–300.4°C), large processing windows (∼106.5°C) with low melt viscosities, and excellent thermal stabilities. Then, the polymerization reaction and surface structures of BAPh/PEN-OH systems were investigated using Fourier transform infrared and scanning electron microscopy, respectively. The interpenetrating polymer networks were found in BAPh/PEN-OH polymers, suggesting that the addition of PEN-OH can not only promote the curing behaviors of BAPh but also increase the toughness of the polymers. The flexure strength and modulus of BAPh/PEN-OH polymers increased with the introduction of PEN-OH. The dielectric properties of BAPh/PEN-OH polymers were investigated, which had little dependence on the frequency. BAPh/PEN-OH systems can be used as a good candidate for high-performance polymeric materials.

Organophilic Boehmite Nanoparticles by ATRP Methacrylates Polymerization: Synthesis, Characterization and Dispersion in Polypropylene

2008 ◽  
Vol 8 (4) ◽  
pp. 1803-1811 ◽  
Author(s):  
Serena Coiai ◽  
Elisa Passaglia ◽  
Sylvain Augier ◽  
Piero Narducci ◽  
Francesco Ciardelli
Keyword(s):  
Physical Adsorption ◽  
Thermo Gravimetric Analysis ◽  
Attenuated Total Reflection ◽  
Polymer Chains ◽  
Gravimetric Analysis ◽  
Scanning Calorimetry ◽  
Polymer Shell ◽  
Grafted Polymer ◽  
Boehmite Nanoparticles ◽  
Morphology Characterization

Boehmite nanoparticles covered with a polymer shell enhancing the organophilicity of the surface were prepared by physical adsorption of a polyelectrolyte atom transfer radical polymerization (ATRP) macroinitiator followed by graft-polymerization of methyl methacrylate or 2-hydroxyethyl methacrylate. The presence of polymer chains adsorbed/grafted on the Boehmite was confirmed by attenuated total reflection infrared (ATR-IR) spectroscopy and by thermo-gravimetric analysis (TGA), which showed a significant amount of polymer covering the particles. The methodology of polymerization and the kinetics suggested the possibility to modulate the amount, type and thickness of grafted polymer shell. These organic–inorganic hybrid materials were melt compounded in a Brabender mixer with isotactic polypropylene in the presence of functionalized polypropylene. The dispersion degree of Boehmite nanoparticles in the polypropylene matrixas well as their reinforcing effect were studied by morphology characterization [scanning electron microscopy (SEM) and X-ray diffraction (XRD)], whereas thermal and thermo-mechanical properties were assessed by differential scanning calorimetry (DSC) and dynamic mechanical thermal analysis (DMTA).

scholarly journals Application of near-infrared spectroscopy for the rapid analysis ofLonicerae Japonicae Flossolution extracted by water

2014 ◽  
Vol 07 (04) ◽  
pp. 1350063 ◽  
Author(s):  
Xue Xiao ◽  
Jinfang Ma ◽  
Fahuan Ge ◽  
Xiangdong Zhang ◽  
Huihua Yang ◽  
...  
Keyword(s):  
Chlorogenic Acid ◽  
Standard Error ◽  
Latent Variable ◽  
High Performance ◽  
Near Infrared ◽  
Process Analytical Technology ◽  
Reference Method ◽  
Nir Spectroscopy ◽  
Variable Number ◽  
Array Detection

A rapid quantitative analytical method for three components of Lonicerae Japonicae Flos solution (Lonicera Japonica Thumb.) extracted by water was developed using near-infrared (NIR) spectroscopy and the partial least-squares (PLS) method. The NIR spectra of 81 samples collected from a production line were obtained. The concentrations of secologanic acid, chlorogenic acid and galuteolin were determined by using high-performance liquid chromatography-diode array detection as the reference method. Several pretreatment methods for the NIR spectra were used during PLS calibration. The most appropriate latent variable number of the PLS factor was selected based on the standard error of cross-validation (SECV). The performance of the final PLS models was evaluated according to SECV, standard error of prediction (SEP) and determination coefficient (R2). The compounds secologanic acid, chlorogenic acid and galuteolin had SEP values of 0.030, 0.061 and 1.668 μg/mL, respectively and R2values over 0.85. This work shows that NIR spectroscopy is a rapid and convenient method for the analysis of Lonicerae Japonicae Flos solution extracted by water. The proposed method can help in the application of process analytical technology in the pharmaceutical industry, particularly in traditional Chinese medicine injections.

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