scholarly journals Properties of Polymer-Composite Used as Fills of Asian Lacquerware: Issues on Restoration Processes of Lacquered Objects from Cultural Heritage

2015 ◽  
Vol 2015 ◽  
pp. 1-8 ◽  
Author(s):  
Anne-Solenn Le Hô ◽  
Isabelle Fabre-Francke ◽  
Caroline Thiphavong
Keyword(s):  
Cultural Heritage ◽  
Mechanical Test ◽  
Chemical Properties ◽  
Composite Systems ◽  
Restoration Practice ◽  
The Common ◽  
Common Problems ◽  
The Stability ◽  
Material Composite ◽  
And Chemical Properties

One of the common problems encountered in lacquerware issued from cultural heritage is the appearance of lifting areas and some losses of material. Composite systems made of commercial polymer and different fills were tested as filling agents for the cracking, splitting, and losses compensation of Asian lacquer. For that purpose, the stability of traditional and modern commercially available materials usually used in the restoration practice of historical lacquerware was assessed. Their thermomechanical and chemical properties and surface state were evaluated by a set of techniques (TGA, DMA, mechanical test, contact angle value, and microtopography). There is a drastic change of the behavior of the interface between fill and Asian lacquer, dependent on the nature of the composite fillers. So the evaluation of materials and processes for the restoration of Asian lacquer were emphasized. The commercial Paraloid B72 used with glass microspheres as additives appeared to be the most stable of all of the investigated fillers.

Salting-out and salting-in experiments with lignosulfonates (LSs)

Holzforschung ◽  
2013 ◽  
Vol 67 (5) ◽  
pp. 549-557 ◽  
Author(s):  
Bernt O. Myrvold
Keyword(s):  
Chemical Properties ◽  
Physical And Chemical Properties ◽  
Salting Out ◽  
Practical Applications ◽  
Common Ion ◽  
The Common ◽  
Common Ion Effect ◽  
The Stability ◽  
Physical And Chemical ◽  
And Chemical Properties

Abstract The solubility of lignosulfonates (LSs) in water is strongly dependent on other ions present in the water phase. The differences in the solubility might strongly influence the measurements of the physical and chemical properties of the LS molecules. A reduced solubility of the LS might also affect its utility in many practical applications. The understanding of the interaction between LSs and various salts is important for both practical and theoretical reasons. Therefore, the effect of salt concentrations on the LS has been investigated for 41 different salts with 14 different cations and 16 different anions. The observations cannot be explained by the common ion effect or the screening effects. On the contrary, it was found that the stability of LS solutions follows the Hofmeister series, with the exception of those ions that will chemically interact with the LS molecule. Moreover, the positions of phosphate (HPO42-) and sulfate (SO42-) ions were reversed.

scholarly journals Performance Study of Grass-Derived Nano-Cellulose and Polycaprolactone Composites for 3D Printing

2021 ◽  
Vol 11 (3) ◽  
pp. 1273
Author(s):  
Chen Feng ◽  
Jiping Zhou ◽  
Xiaodong Xu ◽  
Yani Jiang ◽  
Hongcan Shi ◽  
...  
Keyword(s):  
3D Printing ◽  
Mechanical Test ◽  
Chemical Properties ◽  
Test Results ◽  
Performance Study ◽  
Compression Process ◽  
Ansys Fluent ◽  
Nano Cellulose ◽  
Physical And Chemical ◽  
And Chemical Properties

In recent years, 3D printing has received increasing attention from researchers. This technology overcomes the limitations of traditional technologies by printing precise and personalized scaffold with arbitrary shapes, pore structures, and porosities for the applications in various tissues. The cellulose nanocrystal (CNC) is extracted from Humulus Japonicus (HJS) and mixed with poly(ε-caprolactone) (PCL) to prepare a series of CNC/PCL composites for printing. Based on the analysis of the physical and chemical properties of the series of the CNC/PCL composites, an optimal mass ratio of CNC to PCL was obtained. The Solidworks was used to simulate the stretching and compression process of the scaffolds with three different patterns under an external force. The flow of nutrient solution in the scaffolds with different patterns was simulated by ANSYS FLUENT, and then a new optimization scaffold pattern with a concave hexagon shape was advised based on the simulation results. Collectively, the mechanical test results of the material and scaffold confirmed that the optimal filling amount of the CNC was 5%, and the scaffold pattern with concave hexagon shape exhibited better mechanical properties and suitable for the transport of cells and nutrients, which is expected to be more widely used in 3D printing.

Synthesis and Kinetic Investigations for the Isomerization Process of 2–Hydroxy Chalcone Derivatives

2019 ◽  
Vol 41 (6) ◽  
pp. 1046-1046
Author(s):  
Omar A Shareef Omar A Shareef ◽  
Said A Said and Ali Y Abdulrazaq Said A Said and Ali Y Abdulrazaq
Keyword(s):  
Biological Activities ◽  
Chemical Properties ◽  
Physical And Chemical Properties ◽  
Pseudo First Order Reaction ◽  
First Order ◽  
Steric Factors ◽  
Kinetic Investigations ◽  
The Stability ◽  
Physical And Chemical ◽  
And Chemical Properties

The wide biological activities of flavanones are mainly depends on their physical and chemical properties, thus a number of substituted 2-Hydroxy chalcones have been synthesized, and their isomerization to their corresponding flavanones was studied. In order to determine the rate constant, kinetic experiments were performed using HPLC technique in (9:1) (CH3CN:H2O) medium at different temperature (298-318) K. The obtained results were interpreted by four steps mechanism, which considered the existence of phenoxide ion as the key intermediate. This study performed with a pseudo first order ( reaction in which the rate for the studied compounds follow the sequence 5 andgt; 2 andgt; 1 andgt; 4 andgt; 3, the activation energy have the same sequence for these compounds .The effect of substituents on the rate showed that electronic and steric factors play reasonable role on the stability of the product .

The Establishment of the 3rd National Reference Standard for Tachypleus Tridentatus Lysate

2017 ◽  
Vol 6 (3) ◽  
pp. 50
Author(s):  
Tong Cai ◽  
Guolai Zhang ◽  
Yusheng Pei ◽  
Hua Gao
Keyword(s):  
Chemical Properties ◽  
Physical And Chemical Properties ◽  
Reference Standard ◽  
Tachypleus Tridentatus ◽  
National Reference ◽  
The Stability ◽  
Physical And Chemical ◽  
And Chemical Properties

<p><strong>Objective</strong>  To establish the 3rd national reference standard for Tachypleus Tridentatus Lysate Reagent. <strong>Method</strong> <strong>and Results</strong>  The candidates of reference standard were studied for the physical and chemical properties, and the stability. To determined its sensitivity by collaboration calibration. <strong>Conclusions</strong>  The sensitivity of the 3rd national reference standard for TAL is 0.06EU / ml, lot number is 150603-201003.</p>

Carbon-Bridged Phenylene-Vinylenes: On the Common Diradicaloid Origin of Their Photonic and Chemical Properties

2017 ◽  
Vol 121 (41) ◽  
pp. 23141-23148 ◽  
Author(s):  
Rafael C. González-Cano ◽  
Simone Di Motta ◽  
Xiaozhang Zhu ◽  
Juan. T. López Navarrete ◽  
Hayato Tsuji ◽  
...  
Keyword(s):  
Chemical Properties ◽  
The Common ◽  
And Chemical Properties

scholarly journals COMPLEXATION OF APPLE PECTIN, MODIFIED TO PHARMACOPHORE, WITH THE CATIONS MANGANESE (II) IN AQUEOUS SOLUTIONS

2020 ◽  
pp. 25-32
Author(s):  
Roza Khanifovna Mudarisova ◽  
Alina Failovna Sagitova ◽  
Ol'ga Sergeyevna Kukovinets
Keyword(s):  
Metal Complexes ◽  
Chemical Properties ◽  
Thermodynamic Characteristics ◽  
Standard Thermodynamic Characteristics ◽  
Anthranilic Acids ◽  
Drug Compound ◽  
The Stability ◽  
Physical And Chemical ◽  
And Chemical Properties ◽  
Polymer Ligand

Complex formation in systems containing manganese (II), natural pectin and/or pectin modified by organic pharmacophores (nicotine, salicylic, 5-aminosalicylic, anthranilic acids) was studied by spectral (UV-, IR-, NMR 13C spectroscopy), potentiometric and viscometric methods. Method isomolar series and the molar relationship defined by the molar composition and the range of stability of metal complexes: pectin + nicotinic acid > pectin + acid 5-aminosalicylic > pectin + anthranilic acid > pectin + salicylic acid > native pectin. It is shown that the stability constant of metal complexes is significantly influenced by the reaction temperature and the structure of the pharmacophore. The presence of an amino group in the structure of an aromatic molecule increases the stability of metal complexes by 1.5–2 orders of magnitude. The standard thermodynamic characteristics (∆Hº; ∆Gº; ∆Sº) are calculated, which indicate that the processes of complexation in all cases are enthalpy-entropy favorable (∆Hº<0, ∆Sº>0) and proceed spontaneously (∆Gº<0). The influence of the structure of the drug compound in the polymer ligand on a number of physical and chemical properties of metal complexes was revealed. The data of NMR 13C and IR-spectra allow us to conclude that not only carboxyl groups but also hydroxyl functions of polymer matrices participate in the coordination interaction of pectin and/or pharmacophore-containing pectin with manganese (II) cations.

scholarly journals Comparative Analysis of Structure and Properties of Stereoscopic Cocoon and Flat Cocoon

2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Bin Zhou ◽  
Huiling Wang ◽  
Hongtao Zhou ◽  
Ke Wang ◽  
Shudong Wang ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Chemical Properties ◽  
Morphological Characteristics ◽  
Morphological Structure ◽  
Variable Structure ◽  
Fiber Fineness ◽  
The Common ◽  
Physical And Chemical ◽  
Structure And Functions ◽  
And Chemical Properties

Abstract Cocoon is a kind of natural biopolymer material with reasonable structure and various functions. However, its structure and functions are often destroyed in practical application. In this study, we took common Bombyx Mori as the research object, and provided different cocooning sites for single or multiple silkworms to construct common stereoscopic cocoons (“normal cocoons” [NC]) and flat cocoons (“single-silkworm flat cocoons” [SFC] and “multi-silkworm flat cocoons” [MFC]), respectively, and compared the morphological structure and basic properties of these cocoons. The study found that the flat cocoons have similar multi-layered variable structure and characteristics compared to those of the common cocoons; also, morphological characteristics and physical and chemical properties of silk fiber from outer layer to inner layer, such as sericin content, fiber fineness, and change rule of basic mechanical properties, are completely consistent with those of the common cocoons. It can be considered that the flat cocoons are constructed by silkworms in the same “procedural” process as that of common cocoons. Due to the expansion of cocooning space, the mechanical properties of fibers are significantly improved. By controlling the size of the cocooning space or the quantity of silkworms cocooning simultaneously, and the time of spinning, a cocoon material with controllable thickness, weight per square meter, porosity, and number of cocoon layers can be obtained as a composite material for direct application.

scholarly journals Agrochemical properties of soils of land plots of the Park «Tikhiy Otdykh» of Saint Petersburg

2021 ◽  
pp. 102-117
Author(s):  
В.Ф. Ковязин ◽  
П.М. Демидова ◽  
Е.А. Иванова
Keyword(s):  
Geographical Information Systems ◽  
Current Problem ◽  
Chemical Properties ◽  
Geographical Information ◽  
Physical And Chemical Properties ◽  
Saint Petersburg ◽  
Agrochemical Properties ◽  
The Stability ◽  
Physical And Chemical ◽  
And Chemical Properties

Статья посвящена актуальной проблеме формирования устойчивости парковых насаждений, произрастающих на почвах с различными физико-химическими свойствами. Приведены характерные агрохимические свойства почв парка «Тихий отдых» Санкт-Петербурга. По каждому агрохимическому показателю почвы разработаны с использованием современных географических информационных систем (ГИС) тематические карты в масштабе 1:10000 с применением программного комплекса AutoCAD. С использованием данного комплекса рассчитаны площади земельных угодий, имеющих различные физико-химические свойства почвы. В настоящее время данная проблема городских садово-парковых объектов мало изучена и требует дальнейших исследований, именно этой тематике и посвящены изложенные в статье результаты исследований. The article is devoted to the current problem of forming the stability of Park stands growing on soils with different physical and chemical properties. The characteristic agrochemical properties of the soils of the Park «Tikhiy Otdykh» of St. Petersburg are given. For each agrochemical indicator of the soil, thematic maps were developed using modern geographical information systems (GIS) at a scale of 1:10000 using the AutoCAD software package. Using this complex, the areas of land with different physical and chemical properties of the soil are calculated. At present, this problem of urban garden and Park objects is poorly studied and requires further research. These results presented in the article are devoted to this topic.

Grafting of Hydroxy-Terminated Polybutadiene with 2-Mercaptoethanol

2002 ◽  
Vol 67 (12) ◽  
pp. 1899-1910 ◽  
Author(s):  
Alexander Pleska ◽  
Iva Klichová ◽  
Jindřich Pytela
Keyword(s):  
Chemical Properties ◽  
Radical Addition ◽  
Physical And Chemical Properties ◽  
Scanning Calorimetry ◽  
Polyurethane Elastomers ◽  
Volatile Solvents ◽  
Hydrolytic Resistance ◽  
The Stability ◽  
Physical And Chemical ◽  
And Chemical Properties

A method for functionalization of hydroxy-terminated polybutadiene with 2-sulfanylethan-1-ol (2-mercaptoethanol) leading to a controlled increase in the OH functionality of the polymer was developed. The polybutadiene used contained about 65% of unsaturation in the form of 1,2-vinyl groups. The reaction was carried out without using volatile solvents. The radical addition of 2-sulfanylethan-1-ol on the polymer proceeded quantitatively and the products were free of the mercaptan odour. A series of functionalized polybutadienes were synthesized and characterized by their physical and chemical properties. The differential scanning calorimetry and thermogravimetric analysis measurements revealed that the functionalization improves the stability of the polybutadiene to thermooxidation. The obtained polymers were used for the preparation of polyurethane elastomers. The effect of the increased functionality of the polybutadiene on mechanical properties, thermal behavior and hydrolytic resistance of the elastomers was assessed.

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