scholarly journals Preparation and Photochromic Performance of Homogeneous Phase Nitrocellulose Membrane Grafting Spirooxazine Moieties

Coatings ◽  
2020 ◽  
Vol 10 (6) ◽  
pp. 569
Author(s):  
Bin-Bin Sun ◽  
Bing-Hua Yao ◽  
Yang-Qing He ◽  
Bo Yang
Keyword(s):  
Ethyl Acetate ◽  
Acetate Solution ◽  
Ethyl Acetate Solution ◽  
Colored Form ◽  
Isobutyl Ketone ◽  
Photochromic Properties ◽  
Photochromic Behavior ◽  
Reaction Rate Constants ◽  
13C Nuclear Magnetic Resonance ◽  
Relative Absorption

The synthesis of 1,3,3-trimethyl-9′-acryloxyspiro[indoline-2,3′(3H)naphtho[2,1-b][l,4]-oxazine] (AISO) was carried out by catalytic esterification of 1,3,3-trimethyl-9′-hydroxyspiro-[indoline-2,3′(3H)naphtho[2,1-b][l,4]oxazine] (SO–OH) and acrylic acid in the presence of 1,3-dicyclohexylcarbodiimide (DCC) and N-dimethylaminopyridine (DMAP). Then, the synthesis of the target copolymer (NC-g-AISO) was was carried out by benzoyl peroxide (BPO)-induced graft copolymerization of the AISO monomer onto nitrocellulose (NC) in a homogeneous methyl isobutyl ketone medium. The structure of NC-g-AISO was characterized by Fourier transform infrared (IR) spectroscopy, 13C Nuclear Magnetic Resonance (NMR) spectra and thermogravimetric (TG) analysis. The photochromic properties of NC-g-AISO were investigated by examining UV–Vis spectra in ethyl acetate solution and solid membrane. Compared with the AISO monomer in ethyl acetate solution, the thermal color decay stability of the colored form of NC-g-AISO in ethyl acetate solution and in solid membrane improved significantly. The thermal color decay reaction rate constants in ethyl acetate solution and membrane at 25 °C were 1.77 × 10–2 and 1.36 × 10–3 s–1, respectively, fitted using the first-order reaction equation. After ten photochromic cycles, the relative absorption intensity of the colored form of NC-g-AISO decreased by 0.85%, indicating that the NC-g-AISO membrane has good reversible photochromic behavior.

Spectrophotometric Determination of Capsaicin

1977 ◽  
Vol 60 (4) ◽  
pp. 970-972 ◽  
Author(s):  
José Jorge Ramos Palacio
Keyword(s):  
Ethyl Acetate ◽  
Rapid Method ◽  
Spectrophotometric Determination ◽  
Acetate Solution ◽  
Ethyl Acetate Solution

Abstract A rapid method has been developed for determining the pungency of hot paprika. Paprika is extracted with ethyl acetate, and an ethyl acetate solution of vanadium oxytrichloride is added just before reading at 720 nm. The method is sensitive for small quantities, i.e., less than 0.05%, and it is not necessary to isolate and purify the capsaicin.

scholarly journals 4,5-Dichloro-3H-1,2-dithiol-3-one

IUCrData ◽  
2016 ◽  
Vol 1 (11) ◽  
Author(s):  
Khaled Boukebbous ◽  
El Adoui Laifa ◽  
Aimery De Mallmann ◽  
Mostafa Taoufik
Keyword(s):  
Ethyl Acetate ◽  
Carbonyl Group ◽  
Torsion Angle ◽  
Title Compound ◽  
Expected Value ◽  
Planar Geometry ◽  
Acetate Solution ◽  
Ethyl Acetate Solution ◽  
Monoclinic System ◽  
Bond Lengths

The crystallization from an ethyl acetate solution of the title compound, also known as dichloro-1,2-dithiacyclopentenone, C3Cl2OS2, leads to a monoclinic system withP21/nspace group. The molecule displays an almost planar geometry, with a torsion angle of −2.1 (1)° for the endocyclic C—C—S—S fragment. The S—S and C=O bond lengths are 2.0521 (8) and 1.212 (3) Å, respectively. The endocyclic S—C—C angle sustained by the carbonyl group, 110.94 (16)°, deviates from the expected value of 120° for ansp2-hybridized C atom. In the crystal, short S...S, S...Cl, S...O and Cl...Cl contacts are observed.

An Efficient Synthesis of Highly Substituted Spiro[Fluorene-9,3′-[1,2,4]Triazoles from the Reaction of N3-Substituted Amidrazones with (2,4,7-Trinitro-9H-Fluoren-9-Ylidene)Propanedinitrile

2018 ◽  
Vol 42 (3) ◽  
pp. 138-140 ◽  
Author(s):  
Mohsen A.-M. Gomaa ◽  
Huda A. Ali
Keyword(s):  
Ethyl Acetate ◽  
Ambient Temperature ◽  
Acetate Solution ◽  
Ethyl Acetate Solution ◽  
Efficient Synthesis

Novel spiro[fluorene-9,3′-[1,2,4]triazoles were obtained in excellent yields from the reaction of N3-substituted benzamidrazones and (2,4,7-trinitro-9 H-fluoren- 9-ylidene)propanedinitrile in ethyl acetate solution at ambient temperature. The react ion mechanism is discussed.

Synthesis and Application of New Carboxyl Modified Silicone Oil

2013 ◽  
Vol 631-632 ◽  
pp. 437-441
Author(s):  
Ning Lei ◽  
Qiu Feng An ◽  
Jiao Jiao Ning
Keyword(s):  
Maleic Anhydride ◽  
Ethyl Acetate ◽  
Silicone Oil ◽  
Raw Materials ◽  
Water Repellency ◽  
Acetate Solution ◽  
Ethyl Acetate Solution ◽  
Finishing Agent

A kind of new carboxyl and vinyl co-modified silicone oil (Vi-CAS-1) was synthesized with vinyl/amino co-modified silicone oil (Vi-ASO-1) and maleic anhydride (MA) as raw materials. Then 0.03 % Vi-CAS-1 in ethyl acetate solution was used as a finishing agent, the performance of Vi-CAS-1 on dacron fabrics was studied, and the effects of carboxyl equivalent, viscosity and the mole ratio of raw materials such as Vi-ASO-1 to MA on the Vi-CAS-1 performance were also investigated carefully. The results shows that, the elasticity and flexibility of fabrics treated by Vi-CAS-1 significantly increase. And when cooperate with the silicone which contains Si-H (PHMS-0.16 %) in application, the compounded Vi-CAS-1 can improve the fabric water-repellency to some extent, as compared with the fabric treated only with Vi-CAS-1.

scholarly journals PHYTOCHEMICAL STUDY AND THE ANTIPROLIFERATIVE ACTIVITY OF INULA VULGARIS SPECIES GROWN IN LEBANON

2017 ◽  
Vol 9 (8) ◽  
pp. 75
Author(s):  
Assi M. ◽  
Usta J. ◽  
Mounimne Y. ◽  
Aboul Ela M. ◽  
El Lakany A.
Keyword(s):  
Ethyl Acetate ◽  
Antiproliferative Activity ◽  
Trypan Blue ◽  
Heart Diseases ◽  
Trypan Blue Exclusion ◽  
Potent Effect ◽  
Phytochemical Study ◽  
Chemical Structures ◽  
13C Nuclear Magnetic Resonance ◽  
Mtt Assays

Objective: Cancer represents the second leading cause of death after stroke and heart diseases. Plant extracts have long been used in traditional medicine for the prevention and treatment of many illnesses, including some types of cancer. The aim of this study was to evaluate the antiproliferative effects of ethyl acetate fractions of two Lebanese herbs: Inula viscosa (I. vis) and Inula vulgaris (I. vul).Methods: Plants were extracted with ethanol followed by ethyl acetate, then dried and tested on three cell lines including CaCO2, HepG2, and MCF7, to check for their viability and antiproliferative activity, using trypan blue exclusion and 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assays. Proton (1H) and carbon (13C) nuclear magnetic resonance spectrometry (NMR) were used to identify the compounds that have been isolated from both Inula species.Results: The current findings were consistent for both trypan blue and MTT assays. The results showed that the most potent effect for I. vul was HepG2 (IC50 20 µg/ml, 27 µg/ml), and for I. vis on MCF7 (9 µg/ml, 15 µg/ml) and CaCO2 (12 µg/ml, 22 µg/ml) in the two mentioned assays respectively. However, insignificant differences were observed among the studied plants for each of the evaluated cells indicating comparable potencies. Quercetin, quercetin glycoside, and epicatechin derivatives were isolated by fractionation on column chromatography and identified using NMR spectroscopy.Conclusion: The antiproliferative activities of the two plants could be related to their content that is significant for high levels of secondary metabolites. The identification of those compounds is necessary to establish a relationship between their chemical structures and their activities.

scholarly journals Ekstraksi senyawa fenolik antioksidan dari daun dan tangkai gambir

2018 ◽  
Vol 12 (2) ◽  
pp. 250
Author(s):  
Margareth Gani ◽  
Yesisca Cuaca ◽  
Aning Ayucitra ◽  
Nani Indraswati
Keyword(s):  
Antioxidant Activity ◽  
Solvent Extraction ◽  
Ethyl Acetate ◽  
Modern Medicine ◽  
Ethanol Solution ◽  
Total Phenolic ◽  
Acetate Solution ◽  
Extraction Temperature ◽  
Extraction Condition ◽  
Solvent Extraction Method

Extraction of phenolic compounds from leaves and stems of uncaria gambirGambir (Uncaria gambir) contains catechin polyphenols (catechins) which is useful as natural antioxidant to counteract free radicals. Gambir may also be used in modern medicine, also as paint or dye clothing. The objective of this research was to study the effect of type of solvent, solvent concentration, and extraction temperature to the yield and Total Phenolic Content (TPC) of extracts. Gambir was firstly blended without the addition of water prior to extraction using a solvent extraction method. The filtrate was separated from solid residue and evaporated to obtain extract powder. The yield and TPC of the resulting extract powder were then analyzed. Antioxidant activity and catechins content of extracts were also studied. As result, the following extraction condition gave extracts with the highest yield and TPC: with 50% ethanol solution as solvent at 75 oC gave 11.12% and 52.352 g GAE/100 g gambir extract, respectively; whilst with 70% ethyl acetate solution as solvent at 65 oC gave 5.28% and 59.346 g GAE/100 g gambir extract, respectively. The antioxidant activity of extracts, calculated as IC50, for solvent ethanol and ethyl acetate were as follows: 8.9 mg extract/mL and 13.8 mg extract/mL, respectively; whilst the catechins content of extracts were 62,18% and 44,85%, respectively.Keywords: Uncaria gambir, solvent extraction, catechins, antioxidants AbstrakGambir (Uncaria gambir) mengandung polifenol katekin (catechin) yang bermanfaat sebagai bahan antioksidan alami yang dapat menangkal radikal bebas. Selain itu, gambir juga dimanfaatkan dalam pembuatan obat-obatan modern dan pewarna cat atau pakaian. Penelitian ini bertujuan untuk mempelajari pengaruh jenis pelarut, konsentrasi pelarut, dan suhu ekstraksi terhadap perolehan dan kandungan senyawa fenolik (TPC) ekstrak gambir. Daun dan tangkai gambir mula-mula diblender tanpa penambahan air. Proses ekstraksi gambir dilakukan pada berbagai jenis pelarut, konsentrasi pelarut, dan suhu ekstraksi denganmetode ekstraksi pelarut. Setelah padatan dipisahkan dengan pelarutnya, pelarut diuapkan untuk mendapatkan serbuk ekstrak gambir. Serbuk ekstrak gambir dianalisis perolehan dan kandungan senyawa fenoliknya. Aktivitas antioksidan dan kadar katekin ekstrak juga dianalisis. Ekstrak daun gambir dengan perolehan dan TPC tertinggi untuk pelarut etanol (11,12% dan 52,352 g GAE/100 g gambir ekstrak) diperoleh pada konsentrasi etanol 50% dan suhu ekstraksi 75oC. Untuk pelarut etil asetat, perolehan dan TPC tertinggi (5,28% dan 59,346 g GAE/100 g gambir ekstrak) diperoleh pada konsentrasi etil asetat 70% dan suhu ekstraksi 65 oC. Pada masing-masing kondisi terbaik tersebut, ekstrak yang didapat memiliki aktivitas antioksidan (dalam IC50) dan kadar katekin sebesar 8,9 mg ekstrak/mL dan 62,18% untuk ekstraksi dengan pelarut etanol serta 13,8 mg ekstrak/mL dan 44,85% untuk pelarut etil asetat.Kata kunci: Uncaria gambir, ekstraksi pelarut, katekin, antioksidan 

scholarly journals Nanoparticles (NPs) of WO3-x Compounds by Polyol Route with Enhanced Photochromic Properties

Nanomaterials ◽  
2019 ◽  
Vol 9 (11) ◽  
pp. 1555 ◽  
Author(s):  
Bourdin ◽  
Gaudon ◽  
Weill ◽  
Duttine ◽  
Gayot ◽  
...  
Keyword(s):  
Vacancy Concentration ◽  
Annealing Treatment ◽  
Polyol Synthesis ◽  
Crystallographic Structure ◽  
Oxygen Vacancy Concentration ◽  
Photochromic Properties ◽  
Photochromic Behavior ◽  
Monoclinic System ◽  
Electronic Band ◽  
Post Annealing

Tungsten trioxide (WO3) is well-known as one of the most promising chromogenic compounds. It has a drastic change of coloration induced from different external stimuli and so its applications are developed as gas sensors, electrochromic panels or photochromic sensors. This paper focuses on the photochromic properties of nanoWO3, with tunable composition (with tunable oxygen sub-stoichiometry). Three reference samples with yellow, blue and black colors were prepared from polyol synthesis followed by post annealing under air, none post-annealing treatment, or a post-annealing under argon atmosphere. These three samples differ in terms of crystallographic structure (cubic system versus monoclinic system), oxygen vacancy concentration, electronic band diagram with occurrence of free or trapped electrons and their photochromic behavior. Constituting one main finding, it is shown that the photochromic behavior is highly dependent on the compound’s composition/color. Rapid and important change of coloration under UV (ultraviolet) irradiation was evidenced especially on the blue compound, i.e., the photochromic coloring efficiency of this compound in terms of contrast between bleached and colored phase, as the kinetic aspect is high. The photochromism is reversible in a few hours. This hence opens a new window for the use of tungsten oxide as smart photochromic compounds.

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