Improving coloration time and moisture stability of photochromic viologen–carboxylate zwitterions

2018 ◽  
Vol 42 (18) ◽  
pp. 15466-15471 ◽  
Author(s):  
Pei-Yu Guo ◽  
Cai Sun ◽  
Ning-Ning Zhang ◽  
Li-Zhen Cai ◽  
Ming-Sheng Wang ◽  
...  
Keyword(s):  
Coordination Compound ◽  
Color Change ◽  
Moisture Stability

The coordination compound [Zn2LCl4]n (ZnLCl) showed greater moisture stability and faster color change than the viologen ligand L (N,N′-dipropionate-4,4′-bipyridinium).

Photochromic Coordination Compound: Oxygen-Assisted Photoinduced Color Change for Triplet Oxygen Detection

2021 ◽  
Author(s):  
Cao-Ming Yu ◽  
Xian Zhang ◽  
Yong-Qin Wei ◽  
Li-Zhen Cai ◽  
Ming-Sheng Wang ◽  
...  
Keyword(s):  
Coordination Compound ◽  
Color Change ◽  
Oxygen Detection

Color Change Can Be Earliest Sign of Melanoma

2005 ◽  
Vol 38 (22) ◽  
pp. 16
Author(s):  
TIMOTHY F. KIRN
Keyword(s):  
Color Change

Assessment of Color Stability of Treated Leathers with Silicone Oil and Polyethylene Glycol

2014 ◽  
Vol 1 (1) ◽  
pp. 24-34
Author(s):  
Alireza K. ◽  
Hossein Ahmadi ◽  
Mohsen Mohammadi
Keyword(s):  
Ascorbic Acid ◽  
Polyethylene Glycol ◽  
Treatment Process ◽  
Color Change ◽  
Silicone Oil ◽  
Accelerated Aging ◽  
Color Stability ◽  
Antioxidant Additive ◽  
Before And After ◽  
Aesthetic Values

Lubricants and leather dressings are the most common treatments of dry and water logged historical leathers. Color change has a great importance during the time and treatment process, due to visual and aesthetic values of historic leather relics. Polyethylene glycol (PEG) and silicone oil (SiO) are frequently used leather dressings in the conservation procedures. Therefore, color stability of treated leathers with PEG and SiO were investigated before and after heat accelerated aging. Moreover, application of ascorbic acid was evaluated as an antioxidant additive for PEG (PEG+AA).Color change after treatment and aging were studied by colorimetry technique in the CIE *L*a*b system. Results indicated to severe color alteration in PEG treated and aged leathers with or without ascorbic acid. Whereas, SiO treated samples showed better stability and minimum color shift after aging. Silicone oil was characterized as the best dressing for historical leathers with compared to PEG and PEG+AA, due to its high stability and aesthetical properties.

Laser Influence on Dental Sensitivity Compared to Other Light Sources Used During In-office Dental Bleaching: Systematic Review and Meta-analysis

2020 ◽  
Vol 45 (6) ◽  
pp. 589-597
Author(s):  
BGS Casado ◽  
EP Pellizzer ◽  
JR Souto Maior ◽  
CAA Lemos ◽  
BCE Vasconcelos ◽  
...  
Keyword(s):  
Randomized Clinical Trials ◽  
Color Change ◽  
Meta Analysis ◽  
Present Review ◽  
Cochrane Library ◽  
Light Sources ◽  
Eligibility Criteria ◽  
Tooth Color ◽  
Significant Difference ◽  
Meta Analyses

Clinical Relevance The use of laser light during bleaching will not reduce the incidence or severity of sensitivity and will not increase the degree of color change compared with nonlaser light sources. SUMMARY Objective: To evaluate whether the use of laser during in-office bleaching promotes a reduction in dental sensitivity after bleaching compared with other light sources. Methods: The present review was conducted following the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) and is registered with PROSPERO (CDR42018096591). Searches were conducted in the PubMed/Medline, Web of Science, and Cochrane Library databases for relevant articles published up to August 2018. Only randomized clinical trials among adults that compared the use of laser during in-office whitening and other light sources were considered eligible. Results: After analysis of the texts retrieved during the database search, six articles met the eligibility criteria and were selected for the present review. For the outcome dental sensitivity, no significant difference was found favoring any type of light either for intensity (mean difference [MD]: −1.60; confidence interval [CI]: −3.42 to 0.22; p=0.09) or incidence (MD: 1.00; CI: 0.755 to 1.33; p=1.00). Regarding change in tooth color, no significant differences were found between the use of the laser and other light sources (MD: −2.22; CI: −6.36 to 1.93; p=0.29). Conclusions: Within the limitations of the present study, laser exerts no influence on tooth sensitivity compared with other light sources when used during in-office bleaching. The included studies demonstrated that laser use during in-office bleaching may have no influence on tooth color change.

On the reliability of volume-based thermodynamics for inorganic-organic salts and coordination compounds with uncharged ligands

2017 ◽  
Author(s):  
Robson de Farias
Keyword(s):  
Coordination Compound ◽  
Coordination Compounds ◽  
Formation Enthalpy ◽  
Lattice Energy ◽  
Chemical Hardness ◽  
Acid Anion ◽  
Organic Salts ◽  
Density Values ◽  
Lattice Energies

In the present work, the reliability of the volume-based thermodynamics (VBT) methods in the calculation of lattice energies is investigated by applying the “traditional” Kapustinskii equation [8], as well as Glasser-Jenkins [3] and Kaya [5] equations to calculate the lattice energies for Na, K and Rb pyruvates [9-11] as well as for the coordination compound [Bi(C<sub>7</sub>H<sub>5</sub>O<sub>3</sub>)<sub>3</sub>C<sub>12</sub>H<sub>8</sub>N<sub>2</sub>] [17] (in which C<sub>12</sub>H<sub>8</sub>N<sub>2</sub> = 1,10 phenathroline and C<sub>7</sub>H<sub>5</sub>O<sub>3</sub><sup>-</sup>= <i>o</i>-hyddroxybenzoic acid anion). As comparison, the lattice energies are also calculated using formation enthalpy values for sodium pyrivate and [Bi(C<sub>7</sub>H<sub>5</sub>O<sub>3</sub>)<sub>3</sub>C<sub>12</sub>H<sub>8</sub>N<sub>2</sub>]. For the pyruvates, is verified that none of the considered approach, Kapustinskii, Glasser, Kaya or density, provides values that agrees in an acceptable % difference, with the lattice energy values calculated from the formation enthalpy values. However, it must be pointed out that Kaya approach, with deals with a chemical hardness approach is the better one for such kind of inorganic-organic salts. Based on data obtained for [Bi(C<sub>7</sub>H<sub>5</sub>O<sub>3</sub>)<sub>3</sub>C<sub>12</sub>H<sub>8</sub>N<sub>2</sub>] is concluded that the only one VBT method that provides reliable lattice energies for compounds with bulky uncharged ligands is that one based on density values (derived by Glasser-Jenkins).

COLOUR FILTERS APPLICATION FOR DIAGNOSTICS SOME PATHOLOGICAL PROCESS

1970 ◽  
pp. 44-49
Author(s):  
A. G. Belova ◽  
E. V. Zimina ◽  
N. P. Simbirtsev
Keyword(s):  
Visual Analysis ◽  
Color Change ◽  
Incident Light ◽  
Venous Blood ◽  
Subjective Assessment ◽  
Pathological Process ◽  
Dark Spot ◽  
High Reflectivity ◽  
Arterial Blood ◽  
Green Background

During a pathoanatomic autopsy, it is very important to correctly assess the color change of the organs. However, it is not always clear because the color depends on the spectrum of the incident light. There is also a subjective assessment of color. In addition, in animals with large amounts of circulating blood, for example, dogs, early imbibition occurs, which makes it difficult to assess the color of the organ and pathoanatomical diagnosis. We have proposed a simple and visual method of recognition of two pathological processes – inflammation and edema using colored filters. This technique also allows to accurately differentiate inflammation from postmortem imbibition, to recognize fibrin and hemorrhage well. Postmortem examination of different types of animals (predacious families of mustelids, canids, felids) was performed in accordance with Shore’s method in the prosectorium of the Pathonomy Department, K.I. Skryabin Moscow State Academy of Veterinary Medicine and Biotechnology visual analysis – under various artificial lights (fluorescent lamps with banded spectrum and halogen lamps). In the red filter are well identified the pathological processes associated with the venous blood presence in the tissues (venous hyperemia and pulmonary edema). The focus of venous hyperemia or edema in the red filter looks like a dark zone, and tissues, where arterial bloods predominated, aren’t detected in red filter. In the yellow – green filter the inflammation is clearly detected: the zone is brightly red and surrounding tissues become dark. Red colour filters have rather narrow band of transmittance from 600 to 700 nm. Yellow-green have a width zone – from 500 to 700 nm, including both red, and yellow-green part of spectrum. Oxidized hemoglobin in red part of spectrum absorbs ten time weaker, has more high reflectivity and looks red. Surrounding tissues reflect the red rays, which incident on them also red. Therefore, the zone of edema, venous hyperemia and hemorrhaging, containing venous blood, are detected the dark spot, and inflammation zone merges with the red background. Oxidized hemoglobin in the red spectrum part absorbs ten time weaker than reduced hemoglobin, has high reflectivity of the red spectrum part and looks brightly red, surrounding tissues reflect yellow-green spectrum part and look green. Therefore, the zones of inflammation, active hyperemia and hemorrhaging, containing arterial blood, sharp contrast with green background and are clearly visible. Diagnoses made with the help of color filters are confirmed by histological studies.

Reasons for Color Change in Roofing Granules Colored by Ceramic Method

2018 ◽  
Vol 756 (1-2) ◽  
pp. 106-110
Author(s):  
A.S. ALMATOV ◽  
◽  
E.O. KALISTRATOVA ◽  
Keyword(s):  
Color Change ◽  
Ceramic Method

TOKSISITAS AKUT INFUSA KULIT ARI KACANG TANAH (Arachis hypogea L.) PADA MENCIT BALB/ C

2018 ◽  
Vol 15 (2) ◽  
pp. 62
Author(s):  
Risha Fillah Fithria ◽  
Ririn Lispita Wulandari ◽  
Devi Nisa Hidayati ◽  
Lilis Rejeki
Keyword(s):  
Single Dose ◽  
Color Change ◽  
Negative Control ◽  
Control Group ◽  
Hair Color ◽  
Peanut Shell ◽  
Control Group Design ◽  
Safety Standards ◽  
Arachis Hypogea ◽  
Passive Behavior

ABSTRACTPeanut shell (PS) infusion has been shown to be antithrombocytopenia, but there has been no research on safety standards. This study aims to identify the symptoms of toxic effects, the potency of toxicity and histopathology of liver male Balb/C mice after a single dose of PS infusion. This research uses randomized matched posttest only control group design. Twenty five mice were divided into 5 orally dosage groups, ie, PS infusion with a dose of 0,026; 0.052; 0.104; 0.208 g/20gBW; and negative control of CMC Na 0.5%. The observation period is for 14 days. The results showed that single dose of PS infusion had a pseudo LD50 value ie > 0.208g/20gBW which was practically non toxic. Symptoms to watch out for the BW infusion were passive behavior, bradycnea, hair color change, hair loss, and weight loss at doses of 3 and 4. It is unclear whether liver damage ie inflammation, necrosis, and albuminous degeneration caused by PS infusion or other causes.keywords: acute toxicity, infusion, peanut shell

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