Efficient curing of high performance coatings using high peak irradiance uv light

1997 ◽  
Vol 80 (6) ◽  
pp. 274-278 ◽  
Author(s):  
D Skinner
Keyword(s):  
High Performance ◽  
Uv Light ◽  
High Peak

Patulin Surveillance in Apple Cider and Juice Marketed in Michigan

2009 ◽  
Vol 72 (6) ◽  
pp. 1255-1261 ◽  
Author(s):  
KERRI L. HARRIS ◽  
GERD BOBE ◽  
LESLIE D. BOURQUIN
Keyword(s):  
High Performance ◽  
Apple Juice ◽  
Solid Phase ◽  
Uv Light ◽  
Grocery Store ◽  
Grocery Stores ◽  
Apple Cider ◽  
Shelf Stable ◽  
Retail Grocery

Patulin is the most common mycotoxin found in apples and apple juices. The objective of this study was to determine the concentrations of patulin in (i) apple cider produced and marketed by Michigan apple cider mills during the fall seasons of 2002 to 2003 and 2003 to 2004 and (ii) apple juice and cider, including shelf-stable products, marketed in retail grocery stores in Michigan throughout 2005 and 2006. End product samples (n = 493) obtained from 104 Michigan apple cider mills were analyzed for patulin concentration by using solid-phase extraction followed by high-performance liquid chromatography. Patulin was detected (≥4 μg/liter) in 18.7% of all cider mill samples, with 11 samples (2.2%) having patulin concentrations of ≥50 μg/liter. A greater percentage of cider samples obtained from mills using thermal pasteurization contained detectable patulin (28.4%) than did those from mills using UV light radiation (13.5%) or no pathogen reduction treatment (17.0%). Among retail grocery store samples (n = 159), 23% of apple juice and cider samples contained detectable patulin, with 18 samples (11.3%) having patulin concentrations of ≥50 μg/liter. The U.S. Food and Drug Administration (FDA) action level for patulin is 50 μg/kg. Some apple juice samples obtained from retail grocery stores had exceptionally high patulin concentrations, ranging up to 2,700 μg/liter. Collectively, these results indicate that most apple cider and juice test samples from Michigan were below the FDA action level for patulin but that certain apple cider and juice processors have inadequate controls over patulin concentrations in final products. The industry, overall, should focus on improved quality of fruit used in juice production and improve culling procedures to reduce patulin concentrations.

scholarly journals SIMULTANEOUS DETERMINATION OF DIPHENHYDRAMINE, EPHEDRINE, NOSCAPINE, AND GLYCEROL GLYCOLATE USING STABILITY-INDICATING HIGH-PERFORMANCE LIQUID CHROMATOGRAPHY: APPLICATION TO NOSCOF TABLETS

2019 ◽  
pp. 505-511
Author(s):  
PULAGURTHA BHASKARARAO ◽  
GOWRI SANKAR DANNANA
Keyword(s):  
High Performance Liquid Chromatography ◽  
Liquid Chromatography ◽  
High Performance ◽  
Uv Light ◽  
Reversed Phase ◽  
Hplc Method ◽  
Stability Indicating ◽  
Rp Hplc ◽  
Relative Standard ◽  
Validation Parameters

Objective: Noscof tablet is a fixed dosage combination formulation having diphenhydramine (DH), ephedrine (ED), noscapine (NP), and glycerol glycolate (GG). A sensitive, selective, accurate, precise, and stability-indicating reversed-phase high-performance liquid chromatography (RP-HPLC) method with photodiode array detection has been developed and validated for simultaneous analysis of DH, ED, NP, and GG in bulk drug and Noscof tablets. Methods: Reversed-phase chromatographic separation and analysis of DH, ED, NP, and GG were done on an Altima C18 column with 0.01 M KH2PO4 buffer (pH 3.5) and acetonitrile (50:50%, v/v) as mobile phase at 0.8 ml/min flow rate in isocratic mode. Detection was performed at 260 nm. The method was validated in harmony with International Conference on Harmonization (ICH) guidelines. The tablet sample solution was subjected to diverse stress conditions using ICH strategy such as hydrolytic degradation (neutral - with distilled water, alkaline - with 2 N NaOH, and acidic - with 2 N HCl), oxidation (with 10% H2O2), photodegradation (exposing to UV light), and dry heat degradation (exposing to 105°C). Results: Using the above stated chromatographic conditions, sharp peaks were obtained for ED, NP, DH, and GG with retention time of 3.272 min, 4.098 min, 5.467 min, and 6.783 min, respectively. Good regression coefficient values were obtained in the range of 2–12 μg/ml for ED, 3.75–22.5 μg/ml for NP, 3.125–18.75 μg/ml for DH, and 25–150 μg/ml for GG. The quantification limits were 0.181 μg/ml, 0.187 μg/ml, 0.246 μg/ml, and 1.114 μg/ml for ED, NP, DH, and GG, respectively. The values of validation parameters are within the acceptance limits given by ICH. The ED, NP, DH, and GG showed more percent of degradation in acid condition and less percent of degradation in the neutral condition. The peaks of degradants did not interfere with the peaks of analytes. ED, NP, DH, and GG were assessed with a good percentage of the assay (near to 100%) and low percent relative standard deviation (<2%) in Noscof tablets using the proposed method. Conclusion: The stability indicating RP-HPLC method developed was suitable for quantifying ED, NP, DH, and GG simultaneously in bulk as well as in tablet formulation.

scholarly journals Identification of phenolic compounds of dry extract of dandelion herb and large burdock leaf tea

2019 ◽  
Vol 18 (2) ◽  
pp. 73-77
Author(s):  
L. M. Fedoseeva ◽  
Yu. I. Chistova
Keyword(s):  
High Performance Liquid Chromatography ◽  
Liquid Chromatography ◽  
Phenolic Compounds ◽  
High Performance ◽  
Uv Light ◽  
Spectral Characteristics ◽  
Water System ◽  
Dry Extract ◽  
Caffeic Acid Derivatives ◽  
Layer Chromatography

The purpose of this work is to study of phenolic compounds in the dry extract of dandelion herb and large burdock leaf tea.Materials and methods . The separation and identification of phenolic compounds of dry extract of dandelion herb and large burdock leaf tea by thin-layer chromatography and high-performance liquid chromatography with UV-detectionhas been carried out.Results . As a result of research, it has been established that during TLC the optimal system for the separation of phenolic compounds is the ethyl acetate – formic acid – water system (10:2:3). On the chromatogram four spots were found corresponding to the value of Rf and fluorescence in UV-light to flavonoids of the flavone group and phenolic acids (chlorogenic and caffeic acids). For further identification of phenolic compounds using HPLC, eight peaks were found, which in terms of retention time and spectral characteristics correspond to phenologlycosides, chlorogenic acid, caffeic acid derivatives, ferulic acid, umbelliferone.Conclusions . Thus, the dry extract of dandelion herb and large burdock leaf tea contains hydroxycinnamic acids and their derivatives, compounds of coumarin nature, phenologlycosides.

scholarly journals TIPS-Naphthalene for Efficient Visible-to-UV Photon Upconversion under Sunlight and Room Light

2020 ◽  
Author(s):  
Naoyuki Harada ◽  
Yoichi Sasaki ◽  
Masanori Hosoyamada ◽  
Nobuo Kimizuka ◽  
Nobuhiro Yanai
Keyword(s):  
High Performance ◽  
Uv Light ◽  
Light Sources ◽  
Solar Simulator ◽  
Visible Absorption ◽  
Excitation Light ◽  
Uv Emission ◽  
Threshold Excitation ◽  
Weak Light ◽  
Optimized Conditions

Until now, the efficiency of triplet-triplet annihilation-based photon upconversion (TTA-UC) from visible to ultraviolet (UV) light has been limited to ca. 10% due to the absence of high-performance acceptors (emitters). Here, we present the first example of visible-to-UV TTA-UC internal efficiency <i>η</i><sub>UC</sub> beyond 20% by developing a novel UV emitter, 1,4-bis((triisopropylsilyl)ethynyl)naphthalene (TIPS-Nph), and sensitizing its triplet by a donor Ir(C6)<sub>2</sub>(acac) with strong visible absorption and weak UV absorption. Under optimized conditions, 97% of the excitation light is absorbed, the threshold excitation intensity (<i>I</i><sub>th</sub> = 1.1 mW cm<sup>−2</sup>) is lower than the solar irradiance (1.4 mW cm<sup>−2</sup> for 445 ± 5 nm), and significantly, the highest external UC efficiency <i>η</i><sub>UC,ext</sub> of 17.4% for vis-to-UV TTA-UC is achieved. Upconverted UV emission can also be obtained with weak light sources such as an AM 1.5 solar simulator and room LEDs, paving the way for a variety of solar and indoor applications.

Polarization-Insensitive Dielectric Metamaterials Absorber for Near-Unity UV-Light Trapping in Monolayer Graphene

2020 ◽  
Author(s):  
Yinong Xie ◽  
Xueying Liu ◽  
Yijun Cai ◽  
Jinfeng Zhu
Keyword(s):  
Magnetic Resonance ◽  
High Performance ◽  
Uv Light ◽  
Light Trapping ◽  
Normal Incidence ◽  
Resonant Absorption ◽  
Base Layer ◽  
Absorption Enhancement ◽  
Monolayer Graphene ◽  
Polarization Insensitive

Abstract With the aim of improving UV light trapping capability in monolayer graphene, a metamaterials absorber is proposed, which exhibits the polarization-insensitive feature due to the geometrical symmetry. Through the functional combination of magnetic resonance and UV mirror, the absorption of unpolarized UV light in monolayer graphene can reach 99.5% under normal incidence. The absorption enhancement is induced by the magnetic resonance mode between the dielectric silica nanomesh and the calcium fluoride base layer. The effects of geometric parameters on the absorption spectra are systematically investigated. By optimizing the metamaterials design, two distinct resonant absorption peaks can be excited simultaneously for monolayer graphene. Our work paves the way for applications on high-performance UV metamaterials devices by using two-dimensional materials.

scholarly journals Stability-Indicating High-Performance Liquid Chromatographic Assay of Atorvastatin with Fluorescence Detection

2007 ◽  
Vol 90 (6) ◽  
pp. 1547-1553 ◽  
Author(s):  
Alaa Khedr
Keyword(s):  
High Performance ◽  
Uv Light ◽  
Degradation Products ◽  
High Performance Liquid Chromatographic ◽  
Base Hydrolysis ◽  
Good Resolution ◽  
Stability Indicating ◽  
Limit Of Quantitation ◽  
Bulk Drug ◽  
Liquid Chromatographic

Abstract The purpose of this work was to develop a sensitive, selective, and validated stability-indicating high-performance liquid chromatographic (LC) assay of atorvastatin (ATV) in bulk drug and tablet form. ATV was subjected to different stress conditions, including UV light, oxidation, acid-base hydrolysis, and temperature. ATV and its degradation products were analyzed on an Agilent Zorbax XDB C18 column using isocratic elution with acetonitrile0.02 M sodium acetate, pH 4.2 (45 + 55, v/v) for 25 min. The samples were monitored with fluorescence (FL) detection at 282 nm (excitation)/400 nm (emission). The response ratio of FL to UV detection (at 247 nm) for ATV was 1.66. The method showed good resolution of ATV from its decomposition products. The photodegradation products were separated by silica gel thin-layer chromatography using double development with ethyl acetaten-hexaneglacial acetic acidmethanol (40 + 55 + 0.5 + 4.5, v/v/v/v) followed by (39 + 55 + 0.5 + 5.5, v/v/v/v), and confirmed by LC-FL analysis. The FL response was linear over the investigated range for ATV. The linear range was 101200 ng/injection, and the limit of quantitation was 2.0 ng/injection.

Optical Filter for Fabricating Self-Aligned Amorphous Si TFTS

1999 ◽  
Vol 557 ◽  
Author(s):  
P. Mei ◽  
J. P Lu ◽  
C. Chua ◽  
J. Ho ◽  
Y. Wang ◽  
...  
Keyword(s):  
High Performance ◽  
Uv Light ◽  
Optical Filter ◽  
Device Performance ◽  
Gate Electrode ◽  
Large Area ◽  
New Process ◽  
Amorphous Si ◽  
Difficult Challenge ◽  
Channel Region

AbstractSelf-aligned structures for bottom-gate amorphous Si TFTs provide a number of advantages, including reduced parasitic capacitance, smaller device dimensions, and improved uniformity in device performance for large-area electronics. A difficult challenge in making self-aligned TFT structures is the necessity of making source/drain contacts that exhibit low contact resistances and that are precisely aligned relative to the gate electrode. In this article, we describe a novel process for fabricating self-aligned amorphous Si TFTs. This process utilizes a pulsed excimer laser (308 nm) to dope or to activate dopants in a-Si to form the source/drain contacts. An important feature of the device design is an optical filter to protect the a-Si channel region from radiation damage during the 308 nm laser process. However, the optical filter allows the transmission of the uv light for lithography exposure from the backside of the substrate to align the channel region with the gate electrode. This new process enables the fabrication of high performance self-aligned a-Si TFTs with poly-Si source and drain contacts.

High-performance mixed-dimensional perovskite solar cells with enhanced stability against humidity, heat and UV light

2018 ◽  
Vol 6 (41) ◽  
pp. 20233-20241 ◽  
Author(s):  
Haiying Zheng ◽  
Guozhen Liu ◽  
Xiaojing Chen ◽  
Bing Zhang ◽  
Ahmed Alsaedi ◽  
...  
Keyword(s):  
Solar Cells ◽  
High Performance ◽  
Uv Light ◽  
Perovskite Solar Cells ◽  
Light Stability ◽  
Enhanced Stability

By introducing HOCH2CH2NH3I, new MD perovskite solar cells with a high PCE of 18.79% and improved humidity, heat and UV light stability are obtained.

Spreading of SARS-CoV-2 via Heating, Ventilation, and Air Conditioning Systems—An Overview of Energy Perspective and Potential Solutions

2020 ◽  
Vol 143 (8) ◽  
Author(s):  
Ahmad K. Sleiti ◽  
Samer F. Ahmed ◽  
Saud A. Ghani
Keyword(s):  
Air Conditioning ◽  
High Performance ◽  
Public Perception ◽  
High Efficiency ◽  
Uv Light ◽  
Experimental Studies ◽  
High Energy ◽  
Penalty Cost ◽  
Energy Penalty ◽  
Air Conditioning Systems

Abstract The role of heating, ventilation, and air conditioning systems (HVAC) in spreading SARS-CoV-2 is a complex topic and has not been studied thoroughly. There are some existing strategies and technologies for health and high performance buildings; however, applications to other types of buildings come at large energy penalty: cost; design, regulations and standards changes, and varied public perception. In the present work, different factors and strategies are reviewed and discussed and suggested mitigations and solutions are provided including the required air flowrates with the presence of infectors with and without mask and disinfection techniques including ultraviolet (UV) light. Experimental and numerical research in open literature suggests that the airborne transmission of SARS-CoV-2 is sufficiently likely. However, in situ detailed experimental studies are still needed to understand the different scenarios of the virus spread. Displacement ventilation, underfloor air distribution, chilled beams, radiant ceiling panels, and laminar flow systems have varied effectiveness. High-efficiency particulate arrestance (HEPA) filters and UV light can clean viruses but at high energy cost. Suggested solutions to reduce the infection probability include recommended levels of ventilation and a combination of virus sampling technologies including cyclones, liquid impinger, filters, electrostatic precipitators, and water-based condensation.

scholarly journals Cumulus Cell Expansion, Its Role in Oocyte Biology and Perspectives of Measurement: A Review

2015 ◽  
Vol 45 (4) ◽  
pp. 212-225 ◽  
Author(s):  
J. Nevoral ◽  
M. Orsák ◽  
P. Klein ◽  
J. Petr ◽  
M. Dvořáková ◽  
...  
Keyword(s):  
Extracellular Matrix ◽  
Hyaluronic Acid ◽  
High Performance ◽  
Uv Light ◽  
Cumulus Cell ◽  
Developmental Competence ◽  
Enzyme Linked Immunosorbent Assay ◽  
Cumulus Expansion

Abstract Cumulus expansion of the cumulus-oocyte complex is necessary for meiotic maturation and acquiring developmental competence. Cumulus expansion is based on extracellular matrix synthesis by cumulus cells. Hyaluronic acid is the most abundant component of this extracellular matrix. Cumulus expansion takes place during meiotic oocyte maturation under in vivo and in vitro conditions. Quantification and measurement of cumulus expansion intensity is one possible method of determining oocyte quality and optimizing conditions for in vitro cultivation. Currently, subjective methods of expanded area and more exact cumulus expansion measurement by hyaluronic acid assessment are available. Among the methods of hyaluronic acid measurement is the use of radioactively labelled synthesis precursors. Alternatively, immunological and analytical methods, including enzyme-linked immunosorbent assay (ELISA), spectrophotometry, and high-performance liquid chromatography (HPLC) in UV light, could be utilized. The high sensitivity of these methods could provide a precise analysis of cumulus expansion without the use of radioisotopes. Therefore, the aim of this review is to summarize and compare available approaches of cumulus expansion measurement, respecting special biological features of expanded cumuli, and to suggest possible solutions for exact cumulus expansion analysis.

Sign in / Sign up

Export Citation Format

Share Document