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排序方式: 共有844条查询结果,搜索用时 269 毫秒
831.
832.
Shruthi Manjunath Shenava J. V. Shanmukha Kumar Rajkumar Ganugula Mohammed Rafi Shaik Rosa Busquets Mohammad Rizwan Khan 《Molecules (Basel, Switzerland)》2021,26(23)
Aqueous fluorescent dispersions containing dyed acrylic-based copolymer nanoparticles possess significant credentials concerning green technology as compared to those prepared with the conventional vinyl-based monomers in textile and garment sectors; however, their essential textile fastness properties are yet to achieve. In the present work, a series of acrylic nanodispersions were synthesized by varying the moles ratio of benzyl methacrylate (BZMA), methyl methacrylate (MMA), and 2-hydroxypropyl methacrylate (HPMA) monomers. This was done to study their effect on dye aggregation and dyed polymer particles agglomeration. FT-IR spectral analysis showed the formation of polymer structures, while Malvern Analyzer, Transmission Electron Microscopy, and Scanning Electron Microscopy analysis suggested that the particles are spherical in shape and their size is less than 200 nm. The obtained nanodispersions were later applied on cotton fabrics for the evaluation of wash fastness and colour migration. Premier color scan spectrophotometer and zeta potential measurement studies suggested that colour migration of printed cotton fabrics increased with an increasing agglomeration of particles and it was also observed to increase with the moles ratio of MMA and zeta potentials. 相似文献
833.
Suzana Kutnjak-Mravlin
i Ana Sutlovi Martinia Ira Glogar Sanja Ercegovi Rai Damir Godec 《Molecules (Basel, Switzerland)》2021,26(21)
According to the great impact of additive technology on the development of modern industry, a lot of research is being done to obtain 3D printed parts with better properties. This research is extremely important because there are no scientific papers in the field of post dyeing of acrylonitrile/butadiene/styrene (ABS) 3D printed parts. The experiment was carried out using disperse dyes on ABS specimens. The obtained coloration of the specimens was in the primary colors (yellow, red, and blue) in the specified dyestuff concentration range and was evaluated using an objective CIELab system. Based on the obtained color parameters, remission values and Kubelka-Munk coefficient, dye mixtures and an ombre effect were performed to obtain patterns in the desired hues. Abrasion resistance of disperse dyed specimens was tested using different abrasive materials over a wide range of fineness to simulate different indoor and outdoor soils and was compared to abrasion resistance of specimens produced from the industrially dyed wire with the master batch. The results show that 3D printed ABS products can be produced in one or more desired shades with satisfactory abrasion resistance. This undoubtedly represents the added value of 3D printed ABS parts and extends their application to the field of creative industries and design, specifically footwear design. 相似文献
834.
Shaik Inayath Basha Atta Ur Rehman Md. Abdul Aziz Jung-Hoon Kim 《Chemical record (New York, N.Y.)》2023,23(4):e202200293
3D concrete printing (3DCP) is an emerging additive manufacturing technology in the construction industry. Its challenges lie in the development of high-performance printable materials and printing processes. Recently developed carbon-based nanomaterials (CBNs) such as graphene, graphene oxide, graphene nanoplatelets, and carbon nanotubes, have various applications due to their exceptional mechanical, chemical, thermal, and electrical characteristics. CBNs also have found potential applications as a concrete ingredient as they enhance the microstructure and modify concrete properties at the molecular level. This paper focuses on state-of-the-art studies on CBNs, 3DCP technology, and CBNs in conventional and 3D printable cement-based composites including CBN dispersion techniques, concrete mixing methods, and fresh and hardened properties of concrete. Furthermore, the current limitations and future perspectives of 3DCP using CBNs to produce high-quality composite mixtures are discussed. 相似文献
835.
Alexander Kamyshny Matti Ben‐Moshe Shai Aviezer Shlomo Magdassi 《Macromolecular rapid communications》2005,26(4):281-288
Summary: Two types of ink‐jet inks are presented: ink containing an aqueous dispersion of silver nanoparticles and an oil‐in‐water microemulsion‐based ink. The metallic ink contains nanoparticles of silver, which are formed in the presence of an ionic polymeric stabilizer. Sintering of the printed image obtained with the use of such silver‐based inks at temperatures as low as 300 °C results in formation of patterns possessing noticeable conductivity. The microemulsion inks are based on a thermodynamically stable microemulsion, in which the dispersed oil phase is a volatile solvent containing a water‐insoluble colorant. After contact of the jetted ink droplets with a substrate, nanodroplets of the microemulsion are converted into nanoparticles of the solubilized colorant. In some cases, it was found that the evaporation of microemulsion ink droplets leads to formation of rings composed of ordered nanoparticles.
836.
Photocurable Nitric Oxide-Releasing Copolyester for the 3D Printing of Bioresorbable Vascular Stents
Matheus F. de Oliveira Laura C. E. da Silva Daniele M. Catori Marcos V. Lorevice Karen E. A. Galvão Ana L. G. Millás Marcelo G. de Oliveira 《Macromolecular bioscience》2023,23(3):2200448
The design of bioresorbable vascular stents (BVS) capable of releasing nitric oxide (NO) at the implant site may enable BVS to mimic the antiplatelet, antiproliferative, and pro-endothelial actions of NO, overcoming complications of BVS such as late thrombosis and restenosis. In this study, the fabrication of BVS composed of methacrylated poly(dodecanediol citrate-co-dodecanediol S-nitroso-mercaptosuccinate) (mP(DC-co-DMSNO)), a novel elastomeric, bioabsorbable, and photocurable copolyester, containing covalently bound S-nitrosothiol groups in the carbon backbone of the polymer, is reported. The mP(DC-co-DMSNO) stents are manufactured via photoinduced 3D printing and allow deployment via a self-expansion process from a balloon catheter. After deployment, hydration of the stents triggers the release of NO, which is maintained during the slow hydrolysis of the polymer. Real-time NO release measurements show that by varying the copolyester composition and the strut geometry of the mP(DC-co-DMSNO) stents, it is possible to modulate their NO release rate in the range of 30–52 pmol min−1 cm−2. Preliminary biological assays in cell culture show that endothelial cells adhere to the surface of the stents and that NO release favors their endothelization. Thus, mP(DC-co-DMSNO) may emerge as a new platform for the fabrication of advanced BVS. 相似文献
837.
Tomas Drevinskas Aaron C. Noell Florian Kehl Konstantin Zamuruyev Mauro S. Ferreira Santos Maria F. Mora Travis D. Boone Trinh Hoac Richard C. Quinn Antonio J. Ricco Peter A. Willis 《Electrophoresis》2023,44(13-14):1047-1056
Capillary electrophoresis (CE) holds great promise as an in situ analytical technique for a variety of applications. However, typical instrumentation operates with open reservoirs (e.g., vials) to accommodate reagents and samples, which is problematic for automated instruments designed for space or underwater applications that may be operated in various orientations. Microgravity conditions add an additional challenge due to the unpredictable position of the headspace (air layer above the liquid) in any two-phase reservoir. One potential solution for these applications is to use a headspace-free, flow-through reservoir design that is sealed and connected to the necessary reagents and samples. Here, we demonstrate a flow-through high-voltage (HV) reservoir for CE that is compatible with automated in situ exploration needs, and which can be electrically isolated from its source fluidics (in order to prevent unwanted leakage current). We also demonstrate how the overall system can be rationally designed based on the operational parameters for CE to prevent electrolysis products generated at the electrode from entering the capillary and interfering with the CE separation. A reservoir was demonstrated with a 19 mm long, 1.8 mm inner diameter channel connecting the separation capillary and the HV electrode. Tests of these reservoirs integrated into a CE system show reproducible CE system operation with a variety of background electrolytes at voltages up to 25 kV. Rotation of the reservoirs, and the system, showed that their performance was independent of the direction of the gravity vector. 相似文献
838.
Zoltán Meiszterics András Kiss Lívia Nagy Tamás Zsebe Gyula F. Vasvári Dávid C. Csonka Géza Nagy 《Electroanalysis》2023,35(6):e202200506
The kinetics of oxide layer formation on surface of Ti6Al4V alloy samples is a very important property especially if their application as medical implants is planned. Damaged protective surface layer usually heals in ambient condition however; during the self-healing process toxic species can get into the surrounding living tissue. In our experiment the kinetics of the healing process proceeding at 3D printed alloy surface has been studied using electrochemical methods, among them scanning electrochemical microscopy. More than 40 min. time period was found long enough for total healing. 相似文献
839.
840.
Polydimethylsiloxane (PDMS) based microfluidic devices have found increasing utility for electrophoretic and electrokinetic assays because of their ease of fabrication using replica molding. However, the fabrication of high-resolution molds for replica molding still requires the resource-intensive and time-consuming photolithography process, which precludes quick design iterations and device optimization. We here demonstrate a low-cost, rapid microfabrication process, based on electrohydrodynamic jet printing (EJP), for fabricating non-sacrificial master molds for replica molding of PDMS microfluidic devices. The method is based on the precise deposition of an electrically stretched polymeric solution of polycaprolactone in acetic acid on a silicon wafer placed on a computer-controlled motion stage. This process offers the high-resolution (order 10 m) capability of photolithography and rapid prototyping capability of inkjet printing to print high-resolution templates for elastomeric microfluidic devices within a few minutes. Through proper selection of the operating parameters such as solution flow rate, applied electric field, and stage speed, we demonstrate microfabrication of intricate master molds and corresponding PDMS microfluidic devices for electrokinetic applications. We demonstrate the utility of the fabricated PDMS microchips for nonlinear electrokinetic processes such as electrokinetic instability and controlled sample splitting in ITP. The ability to rapid prototype customized reusable master molds with order 10 m resolution within a few minutes can help in designing and optimizing microfluidic devices for various electrokinetic applications. 相似文献