Morphological Transformations in the Process of Coagulation of Cellulose Solution in N-Methylmorpholine N-Oxide with Isobutanol

2021 ◽  
Vol 63 (2) ◽  
pp. 161-169
Author(s):  
I. S. Makarov ◽  
L. K. Golova ◽  
M. I. Vinogradov ◽  
M. V. Mironova ◽  
N. A. Arkharova ◽  
...  
Keyword(s):  
Cellulose Solution ◽  
Morphological Transformations

Morphological transformations in solution-cast Styrene-Butadiene-Styrene (SBS) triblock copolymer thin films

1995 ◽  
Vol 53 ◽  
pp. 184-185
Author(s):  
Ginam Kim ◽  
W. Marsillo ◽  
M. Libera
Keyword(s):  
Thin Films ◽  
Triblock Copolymer ◽  
Annealing Treatment ◽  
Minor Component ◽  
Solvent Evaporation ◽  
Single Crystal Substrate ◽  
Transparent Films ◽  
Crystal Substrate ◽  
Solution Cast ◽  
Morphological Transformations

The fact that block copolymers can assume a range of morphologies depending upon such variables as relative block length and molecular weight is now well known. In the case of poly(styrene)[PS]-poly(butadiene)[PB]-poly(styrene) (SBS) triblock copolymer, the morphologies range from spheres (roughly ~20% minor component), to cylinders (roughly 20%~35% minor component), to lamellae (roughly equal component fractions) Most recently, there has been increasing interest in transformations between morphologies by thermal annealing. This paper describes initial results studying the effect of solvent evaporation rate and post-casting annealing treatment on the morphology of SBS thin films.TEM specimens were prepared by solution casting electron transparent films. 50 μl of 0.1 wt% SBS (30% styrene, Mw=14,000, Scientific Polymer Products, Inc.) dissolved in toluene was deposited on a polished NaCl single crystal substrate placed in a small dish. After solvent evaporation the film was cut into small squares, floated from the salt in water, and each square was collected on a Cu grid.

Functional, clinical and morphological transformations of the pancreas and metabolic syndrome

2016 ◽  
Vol 18 (8) ◽  
pp. 51-58 ◽  
Author(s):  
L.A. Zvenigorodskaya ◽  
◽  
N.E. Khachaturyan ◽  
Keyword(s):  
Metabolic Syndrome ◽  
Morphological Transformations

Evaluation of the Antiulcer Activity of Ethanolic Leave Extracts of Saraca indica against Ethanol, Pylorus Ligature and Indomethacin Induced Ulcer in Albino Rats

2020 ◽  
Vol 16 (8) ◽  
pp. 1191-1196
Author(s):  
Pritt Verma ◽  
Shravan K. Paswan ◽  
Vishal K. Vishwakarma ◽  
Priyanshi Saxena ◽  
Chandana V. Rao ◽  
...  
Keyword(s):  
Mucosal Injury ◽  
Gastric Volume ◽  
Gastric Ulcers ◽  
Albino Rats ◽  
Antiulcer Activity ◽  
Cellulose Solution ◽  
Total Acidity ◽  
Ulcer Index ◽  
Standard Drug ◽  
High Doses

Background: To evaluate the antiulcer activity of ethanolic leaves extract of Saraca indica against ethanol, pylorus ligature and indomethacin in albino rats. Materials and Methods: Ulcer was produced by ethanol, pylorus ligature and indomethacin in albino rats. Five groups (n=6) of rats were orally pre-treated with carboxymethyl cellulose solution, and ranitidine (80 mg/kg) respectively. In ethanol induced ulcer, the animals were treated with 200 and 400 mg/kg b.w. ethanolic leave extracts of Saraca indica in 0.3% CMC solution, 60 minutes before oral administration of absolute ethanol to produce gastric mucosal injury. In indomethacin induced ulcer, the drug was administered orally at the dose of 30 mg/kg b.w. After 7-9 hours of administration of indomethacin (30 mg/kg); the animals were sacrificed with high doses of anesthesia. In the pylorus ligature method, volume of free acidity, gastric secretion, pH and total acidity were estimated. In all three models, the ulcer index and % protection were estimated. Results: The anti ulcer activity of ethanolic leave extracts of Saraca indica in ethanol, indomethacin and pylorus ligature models is evident from the significant (P<0.001) reduction in ulcer index. In pylorus ligature model, significant (P<0.001) reduction in total acidity gastric volume and increase in pH were observed when compared with the standard drug. Conclusion: Ethanolic leave extracts of Saraca indica were found to be significantly protective against ethanol, indomethacin and pylorus ligature induced gastric ulcers in the experimental albino rats. The result obtained suggest that ethanolic leave extracts of Saraca indica possesses significant anti-ulcer activity.

Design and Optimization of Chronotherapeutic Dosage Form for the Treatment of Angina Pectoris

2020 ◽  
Vol 10 ◽  
Author(s):  
Rupali Singh ◽  
Rishabha Malviya
Keyword(s):  
Drug Delivery ◽  
Angina Pectoris ◽  
Ethyl Cellulose ◽  
Dosage Form ◽  
Cellulose Solution ◽  
Specific Drug ◽  
Pharmaceutical Dosage Form ◽  
Weight Variation ◽  
Short Period ◽  
Time Specific

Background: The chronotherapy concept attains considerable focus towards itself due to its pulsatile fashion rather than continuous delivery. The delivery of the right amount of drug to the target organ at the most appropriate time is fulfilled by using the chronotherapeutic dosage form. Aim: The present study aims to develop and evaluate a chronotherapeutic drug delivery system by using natural polymer for time specific drug delivery at the target site. Material and Method: Tamarind seed polysaccharide was extracted and used in the preparation of core tablets. Nine formulations of core tablets were prepared with nifedipine at 5 tonnes of pressure on 6 mm punch. The core tablets were prepared by using the compression coating method. The three batches F1, F2 and F3 were prepared by using tamarind gum in different concentration i.e. 45%, 22.5% and 67.5% respectively and compressed at 8 tonnes of pressure on 12 mm of punch. The finally compressed tablet was coated with different concentrations of ethyl cellulose in which isopropyl alcohol used as a solvent. In a controlled medium, a stability study was performed to evaluate the physical appearance, drug content and release of the prepared core tablet. Result: All the nine formulations of tablets were prepared successfully and the evaluation studies (thickness, weight variation, hardness, friability etc.) revealed that all the formulations were within the official range. The release study of the drug revealed that the formulation F7 containing 67.5% of tamarind polymer, coated with 2%, 4% and 5% of ethyl cellulose solution released 59.68±1.03% (Q50%) drug within 5 h whereas, 87.09±2.08% (Q80%) within 6 h and within 12 h 97.74±2.19% of the drug was released. The formulation F7 was found to be more effective as it released the maximum amount of drug in a short period as compared with other formulations. Conclusion: The coating of core tablets allowed to prepare pharmaceutical dosage form for time specific drug delivery. These chronotherapeutic core tablets can be used for the treatment of angina pectoris and hypertension etc.

scholarly journals Molecular Correlation between Larval, Deutonymph and Adult Stages of the Water Mite Arrenurus (Micruracarus) Novus

Life ◽  
2020 ◽  
Vol 10 (7) ◽  
pp. 108
Author(s):  
Pedro María Alarcón-Elbal ◽  
Ricardo García-Jiménez ◽  
María Luisa Peláez ◽  
Jose Luis Horreo ◽  
Antonio G. Valdecasas
Keyword(s):  
Culex Pipiens ◽  
Adult Stage ◽  
Gravid Female ◽  
Morphological Characters ◽  
Species Level ◽  
Life Stages ◽  
Water Mite ◽  
Molecular Correlation ◽  
The Common ◽  
Morphological Transformations

The systematics of many groups of organisms has been based on the adult stage. Morphological transformations that occur during development from the embryonic to the adult stage make it difficult (or impossible) to identify a juvenile (larval) stage in some species. Hydrachnidia (Acari, Actinotrichida, which inhabit mainly continental waters) are characterized by three main active stages—larval, deutonymph and adult—with intermediate dormant stages. Deutonymphs and adults may be identified through diagnostic morphological characters. Larvae that have not been tracked directly from a gravid female are difficult to identify to the species level. In this work, we compared the morphology of five water mite larvae and obtained the molecular sequences of that found on a pupa of the common mosquito Culex (Culex) pipiens with the sequences of 51 adults diagnosed as Arrenurus species and identified the undescribed larvae as Arrenurus (Micruracarus) novus. Further corroborating this finding, adult A. novus was found thriving in the same mosquito habitat. We established the identity of adult and deutonymph A. novus by morphology and by correlating COI and cytB sequences of the water mites at the larval, deutonymph and adult (both male and female) life stages in a particular case of ‘reverse taxonomy’. In addition, we constructed the Arrenuridae phylogeny based on mitochondrial DNA, which supports the idea that three Arrenurus subgenera are ‘natural’: Arrenurus, Megaluracarus and Micruracarus, and the somewhat arbitrary distinction of the species assigned to the subgenus Truncaturus.

A Glass Dielectric Paste for Preparation Transparent Spacers of Vacuum Glass by Screen Printing

2012 ◽  
Vol 519 ◽  
pp. 252-255
Author(s):  
Jun Yan Zhao ◽  
Shi Yong Luo ◽  
Xin Lin Zhang ◽  
Wen Cai Xu ◽  
Man Zhao
Keyword(s):  
Network Structure ◽  
Vickers Hardness ◽  
Ethyl Cellulose ◽  
Screen Printing ◽  
Glass Powder ◽  
Flat Glass ◽  
Sound Insulation ◽  
Cellulose Solution ◽  
Glass Substrates ◽  
Melting Glass

Vacuum glass is a new building material with excellent energy conservation and sound insulation properties. Usually, the spacers between two pieces of flat glass substrates are mini-rings of metal. In the present research, the spacers were prepared with a glass dielectric paste by screen printing, and then sintered till them transparent. The glass dielectric paste for the preparation of transparent spacers of vacuum glass was prepared by using low melting glass powder and terpineol ethyl cellulose solution. The composition of the paste with preferable properties was evaluated as in mass percent: organic vehicle 20-25, and low melting glass powder 73-80. The rheological behaviors of the typical paste were characterized by using an ARES (RFS-III) rheometer. It is found that a weak flocculated network structure is formed in the paste for the high solid filler. The spacers were prepared by screen printing the paste on the glass substrate and then sintered. The transparent, Vickers hardness of the spacers as well as the binder forces between the spacers and the substrate is reported. The reliability of the prepared transparent spacers for the vacuum glass was discussed.

Effect of Cellulose Coating on Properties of Cotton Fabric

2016 ◽  
Vol 860 ◽  
pp. 81-84
Author(s):  
Bandu Madhukar Kale ◽  
Jakub Wiener ◽  
Jiri Militky ◽  
Hafiz Shahzad Maqsood
Keyword(s):  
Tensile Strength ◽  
Cotton Fabric ◽  
Solvent System ◽  
Dissolving Pulp ◽  
Cotton Fibers ◽  
Cellulose Solution ◽  
Dyeing Properties ◽  
Sem Micrographs ◽  
Coated Substrate ◽  
Water Solvent

Cellulose solution was used for coating and it was prepared by dissolving pulp cellulose in Urea-Thiourea-NaOH-Water solvent system. Reactive Red 240 dye was used for dyeing the coated as well as control cotton fabric. The effect of cellulose coating on the dyeing properties of cotton fabric was studied by measuring K/S values of the coated substrate at various concentrations of cellulose and dye. K/S value decreased after coating cellulose on the surface of cotton fabric. The lightness of cotton fabric increased after cellulose coating. SEM micrographs revealed that coated cellulose was attached to cotton fibers. Tensile strength increased after cellulose coating.

Dissolution of Cellulose in [Amim]Cl/Lithium Salts Solvents System

2012 ◽  
Vol 535-537 ◽  
pp. 1100-1103 ◽  
Author(s):  
Wei Xiao Liao ◽  
Jun Song ◽  
Bo Wen Cheng ◽  
Jie Mei
Keyword(s):  
Ionic Liquid ◽  
Temperature Increase ◽  
Mass Fraction ◽  
Lithium Salts ◽  
Dissolution Behavior ◽  
Cellulose Solution ◽  
High Concentration

Lithium salts were dissolved in ionic liquid [Amim]Cl, and their dissolution behavior were tested by turbidimeter. It is found that the solubility of LiCl in [Amim]Cl is up to 14g/100g [Amim]Cl at 70°C, and it keeps growing as the temperature increase. Turbidity of cellulose solution in [Amim]Cl at 70°C was obtained, but the solubility of high concentration cellulose solution could not be demonstrated accurately in this way. Cellulose solutions with [Amim]Cl or [Amim]Cl/lithium salts as solvents at different temperature were obtained, in which the lithium salts were 1wt%(mass fraction of [Amim]Cl), polarization microscope was used to observe the dissolution behavior of cellulose. The solubility of cellulose would increased as temperature rose, and the solubility of cellulose in [Amim]Cl/1wt%LiCl reached 11.9%(mass fraction of [Amim]Cl) at 80°C, which was higher than in [Amim]Cl 9.4% at 80°C. It is found that the addition of lithium salts into [Amim]Cl can really improve the solubility of cellulose than in [Amim]Cl.

Particle anisotropy and crystalline phase transition in one-pot synthesis of nano-zirconia: a causal relationship

CrystEngComm ◽  
2018 ◽  
Vol 20 (7) ◽  
pp. 879-888 ◽  
Author(s):  
Francesca Tana ◽  
Andrea Serafini ◽  
Luca Lutterotti ◽  
Alberto Cigada ◽  
Fabio Variola ◽  
...  
Keyword(s):  
Phase Transition ◽  
Phase Composition ◽  
Causal Relationship ◽  
Crystalline Phase ◽  
One Pot ◽  
One Pot Synthesis ◽  
Nanocrystal Growth ◽  
Particle Anisotropy ◽  
Morphological Transformations ◽  
Crystalline Phase Transition

The effects of experimental variables on zirconia nanocrystal growth are investigated, correlating the morphological transformations with phase composition in synthesized nanopowders.

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