Search results for "dab"
showing 10 items of 1280 documents
Effect of small amounts of poly(lactic acid) on the recycling of poly(ethylene terephthalate) bottles
2011
Abstract Poly(ethylene terephthalate) (PET) is one of the most used commodity polymers, especially for food and beverage applications, and its recycling is of great importance because of the possible use in the textile and construction industries. On the other hand, the interest in biodegradable polymers has led, in recent years, to the use of materials such as poly(lactic acid) (PLA) also in the food and beverage industry. The presence of small amounts of PLA in the PET waste can significantly affect the post-consumer recycling process. In this work, the effect of the presence of small amounts of PLA on the recycling of PET bottles is investigated by rheological, mechanical, morphological …
Synthesis of unsaturated β-amino acid derivatives from carbamates of the Baylis–Hillman products
2002
Abstract By treatment with a catalytic amount of DBU in DCM, N-p-toluenesulphonyl carbamates 6a–c , prepared starting from the corresponding Baylis–Hillman adducts, gave (E)-2-(p-toluenesulphonylaminomethyl)propenoates 3a–c , exclusively. On the contrary, changing DABCO for DBU, 2-methylene-3-p-toluenesulfonylamino esters 4a–f were obtained in good yield starting from N-p-toluenesulphonyl carbamates 6a–f . In analogy, N-acyl carbamates 9a–f were treated with DABCO in DCM to give the 2-methylene-3-acylamino esters 5a–f .
ChemInform Abstract: Synthesis of Unsaturated β-Amino Acid Derivatives from Carbamates of the Baylis-Hillman Products.
2010
Abstract By treatment with a catalytic amount of DBU in DCM, N-p-toluenesulphonyl carbamates 6a–c , prepared starting from the corresponding Baylis–Hillman adducts, gave (E)-2-(p-toluenesulphonylaminomethyl)propenoates 3a–c , exclusively. On the contrary, changing DABCO for DBU, 2-methylene-3-p-toluenesulfonylamino esters 4a–f were obtained in good yield starting from N-p-toluenesulphonyl carbamates 6a–f . In analogy, N-acyl carbamates 9a–f were treated with DABCO in DCM to give the 2-methylene-3-acylamino esters 5a–f .
Natural compounds as light stabilizer for a starch-based biodegradable polymer
2014
Abstract The photooxidation behavior of a commercial starch-based biodegradable polymer, i.e., new generation Mater-Bi, loaded with natural stabilizers was investigated in consideration for outdoor agricultural applications. The photooxidation behavior of the biodegradable films was monitored mainly by mechanical tests and spectroscopic analysis. In order to formulate biodegradable films without any synthetic compounds, suitable for outdoor applications and with good photooxidation stability, antioxidants such as α-tocopherol and quercetin (Q) were considered. The results obtained using natural compounds were compared with those obtained by using a synthetic antioxidant and a light stabiliz…
Synthesis of porphyrin-bis(polyazamacrocycle) triads via Suzuki coupling reaction
2014
Suzuki–Miyaura cross-coupling reaction has been used for the synthesis of tricyclic architectures based on trans-A2B2-porphyrins and bisaminal-protected polyazamacrocycles which are linked directly or by a p-phenylene spacer. This modular approach allowed the synthesis of ligands with various substituted porphyrin macrocycles and bisaminal-protected tetraazamacrocycles possessing different cavity sizes. These molecules can be assembled into dimers using a DABCO linker. Deprotection of these compounds afforded porphyrin-bis(polyazamacrocycle) triads.
Inserto di collagene biodegradabile vs mitomicina-C nella trabeculectomia: risultati a medio termine di uno studio prospettico di fase II.
2010
Alma Mater
2016
Upper limits on the isotropic gravitational-wave background from Advanced LIGO and Advanced Virgo's third observing run
2021
We report results of a search for an isotropic gravitational-wave background (GWB) using data from Advanced LIGO's and Advanced Virgo's third observing run (O3) combined with upper limits from the earlier O1 and O2 runs. Unlike in previous observing runs in the advanced detector era, we include Virgo in the search for the GWB. The results are consistent with uncorrelated noise, and therefore we place upper limits on the strength of the GWB. We find that the dimensionless energy density $\Omega_{\rm GW}\leq 5.8\times 10^{-9}$ at the 95% credible level for a flat (frequency-independent) GWB, using a prior which is uniform in the log of the strength of the GWB, with 99% of the sensitivity comi…
Vecākā pirmsskolas vecumposma bērnu izziņas intereses sekmēšanas iespējas brīvdabas pedagoģijā
2021
Darba nosaukums: Vecākā pirmsskolas vecumposma bērnu izziņas intereses sekmēšanas iespējas brīvdabas pedagoģijā. Darba autors: Oļesja Ščeglova Darba vadītājs: Tija Zīriņa Darba mērķis ir izzināt izziņas intereses sekmēšanas iespējas brīvdabas pedagoģijā vecākajā pirmsskolas vecumā. Darba mērķa sasniegšanai vecākā pirmsskolas vecmposma bērniem tika radīta atklājumiem atbilstoša brīvdabas vide, ar iespēju pašvadīti veikt praktisko darbu un eksperimentēt. Darba autore izvirzīja hipotēzi, ka vecākā pirmsskolas vecumposma bērnu izziņas intereses sekmēšana brīvdabas pedagoģijā būs sekmīga, ja skolotājs rada situāciju un pielāgo vidi, kurā bērnam rodas dabiska interese un vajadzība apgūt zināšanas…