Academic literature on the topic 'Non-biodegradable pattern'
Create a spot-on reference in APA, MLA, Chicago, Harvard, and other styles
Consult the lists of relevant articles, books, theses, conference reports, and other scholarly sources on the topic 'Non-biodegradable pattern.'
Next to every source in the list of references, there is an 'Add to bibliography' button. Press on it, and we will generate automatically the bibliographic reference to the chosen work in the citation style you need: APA, MLA, Harvard, Chicago, Vancouver, etc.
You can also download the full text of the academic publication as pdf and read online its abstract whenever available in the metadata.
Journal articles on the topic "Non-biodegradable pattern"
1
Kalachyova, Yevgeniya, Olga Guselnikova, Vladimir Hnatowicz, Pavel Postnikov, Vaclav Švorčík, and Oleksiy Lyutakov. "Flexible Conductive Polymer Film Grafted with Azo-Moieties and Patterned by Light Illumination with Anisotropic Conductivity." Polymers 11, no. 11 (November 11, 2019): 1856. http://dx.doi.org/10.3390/polym11111856.
Full textAbstract:
In this work, we present the method for the creation of an anisotropic electric pattern on thin poly(3,4-ethylenedioxythiophene): polystyrene sulfonate (PEDOT:PSS) films through PSS grafting by azo-containing moieties followed by light-induced polymers redistribution. Thin PEDOT:PSS films were deposited on the flexible and biodegradable polylactic acid (PLLA) substrates. The light-sensitive azo-groups were grafted to PSS using the diazonium chemistry followed by annealing in methanol. Local illumination of azo-grafted PEDOT:PSS films through the lithographic mask led to the conversion of azo-moieties in Z-configuration and further creation of the lateral gradient of azo-isomers along the film surface. The concentration gradient led to the migration of PSS away from the illuminated area, increasing the PEDOT chains’ concentration and the corresponding increase of local electrical conductivity in the illuminated place. Utilization of mask with linear pattern results in the appearance of conductive PEDOT-rich and non-conductive PSS-rich lines on the film surface, and final, lateral anisotropy of electric properties. Our work gives an optical lithography-based alternative to common methods for the creation of anisotropic electric properties, based on the spatial confinement of conductive polymer structures or their mechanical strains.
2
Petkar, Kailash C., Suyash M. Patil, Sandip S. Chavhan, Kan Kaneko, Krutika K. Sawant, Nitesh K. Kunda, and Imran Y. Saleem. "An Overview of Nanocarrier-Based Adjuvants for Vaccine Delivery." Pharmaceutics 13, no. 4 (March 27, 2021): 455. http://dx.doi.org/10.3390/pharmaceutics13040455.
Full textAbstract:
The development of vaccines is one of the most significant medical accomplishments which has helped to eradicate a large number of diseases. It has undergone an evolutionary process from live attenuated pathogen vaccine to killed whole organisms or inactivated toxins (toxoids), each of them having its own advantages and disadvantages. The crucial parameters in vaccination are the generation of memory response and protection against infection, while an important aspect is the effective delivery of antigen in an intelligent manner to evoke a robust immune response. In this regard, nanotechnology is greatly contributing to developing efficient vaccine adjuvants and delivery systems. These can protect the encapsulated antigen from the host’s in-vivo environment and releasing it in a sustained manner to induce a long-lasting immunostimulatory effect. In view of this, the present review article summarizes nanoscale-based adjuvants and delivery vehicles such as viral vectors, virus-like particles and virosomes; non-viral vectors namely nanoemulsions, lipid nanocarriers, biodegradable and non-degradable nanoparticles, calcium phosphate nanoparticles, colloidally stable nanoparticles, proteosomes; and pattern recognition receptors covering c-type lectin receptors and toll-like receptors.
3
Shim, S., B. Kim, Y. Hosoi, and T. Masuda. "Dissolved organic matter from agricultural fields in the irrigation period." Water Science and Technology 52, no. 12 (December 1, 2005): 233–41. http://dx.doi.org/10.2166/wst.2005.0470.
Full textAbstract:
The aim of this study was to quantify and characterize the dissolved organic carbon (DOC) of paddy fields and crop fields in Tottori, Japan. Dissolved organic carbon (DOC) and ultraviolet (UV) absorbance was measured for the filtrated water of each samples. DOC concentration and SUVA (specific UV absorbance) of biodegradation analysis samples were determined around 50 days after the incubation. In the Fukui paddy fields, DOC concentration varied seasonally from 1.1 to 10.1mg.Cl−1, showing higher concentration in heavy runoff of non-agriculture period in April. However, DOC concentration variation did not always correspond to rainfall. The Obadake paddy fields also showed a similar pattern with Fukui paddy fields. The daily DOC discharge per area in Fukui (up), Fukui (down), Obadake (south), Obadake (north) paddy fields influent from paddy fields were 0.02, 0.0161, 0.0135 and 0.0027kg.a−1.day−1, respectively. These differences resulted from differences in agricultural types and customs of farmers according to paddy fields and fields. Also, SUVA (an indirect means to evaluate humic substances (hydrophobic fraction)) of the studied influent waters from paddy fields were generally lower than the influent waters from crop fields. The non-biodegradable DOC accounted for 50.2–98%, 46.8–85.5% of the total DOC in the paddy fields and crop fields.
4
Fatima, Maryam, and Seema Mahmood. "Differential toxicity of Pb & Hg on the development of modular traits, photosynthetic and biochemical attributes in two varieties of a forage crop species Trifolium alexandrinum L." International Journal of Biological Research 4, no. 2 (October 19, 2016): 249. http://dx.doi.org/10.14419/ijbr.v4i2.6755.
Full textAbstract:
Heavy metal stress as result of natural and anthropogenic activities is main environmental problem. Pb and Hg are among non-biodegradable metals thus remaining persistent in soil and water. The present study was carried out to assess growth and biochemical responses of two varieties (Desi and Misri) of Trifolium alexandrinum L. after application of varying levels (25mg/kg, 50mg/kg and 100mg/kg) of Pb and Hg in soil along with control. Seed germination, biomass of above and below ground tissues, number of flowers and leaves, leaf area and nodulation was observed. For biochemical attributes, green pigments, protein and amino acids, were determined. Both varieties (Desi and Misri) showed variable responses in relation to both Pb and Hg. Similarly, the pattern of character expression was independent for metal levels and types. Misri performed consistently better as it showed best threshold for most of the attributes studied. Hg was found to be more toxic as compared to the Pb as it induced more drastic decline in parameters studied. The study showed that biometric traits can be used as good predictors and the biochemical parameters cannot be used as useful biochemical markers as they showed no marked disparity.
5
Boregowda, Sateesha S., Sadanand R. Maggidi, Rajamma A. Jayaramu, Nethravathi Puttegowda, and Nikhat Parbin. "Development of an In situ Gel Polymer Composite for Local and Sustained Delivery of Drugs in Vaginal Cavity." Drug Delivery Letters 9, no. 3 (August 20, 2019): 211–21. http://dx.doi.org/10.2174/2210303109666190226152857.
Full textAbstract:
Objective: The present research work is aimed at the development of an in situ gel polymer composite to provide local and sustained delivery of therapeutic agents in the vaginal cavity. Administration of medicated gel into a vaginal cavity is very complicated, inconvenient and needs expert assistance. There is a chance of expulsion of liquid formulation from site of application, leads to poor therapeutic efficacy. The effective drug delivery system for the vaginal cavity should be of liquid for application and gel to reside in the cavity. Methods: In situ gel composed of chitosan (0.8%) cross-linked with β-glycerol phosphate (15%) and glutaraldehyde treated guar gum (0.2%) was developed. Gel was characterized for in situ gelling properties. In vitro drug release pattern of the gel was tested on a nutrient agar medium containing attenuated E. coli and B. Subtilis. In vitro diffusion pattern of gel was tested using KC-diffusion cell with Simulated Vaginal Fluid (SVF) (pH 4.2) as the diffusion medium. Results: In situ gel exhibited sharpest sol-gel transition at 35±2°C, at pH 5.4 in 62±1.31sec. The viscosity of polymer composite is 51.25±3.68 CPs at 20±2°C and 328.56±4.16 CPs at 35±2°C. The gelation time of gel was found to be decreasing as the concentration of cross-linking agent β-GP increased. Formulations exhibited a shear thinning property. Drug release from this polymeric composite was found to be highly linear and follows non-fickian diffusion mechanism. Conclusion: This advanced thermosensitive in situ gel is convenient to apply and reside in the vaginal cavity for a prolonged period of time. The gel is mucoadhesive, biodegradable and suitable for controlled drug delivery in the cavity.
6
Siriorn, Isarankura Na Ayutthaya, and Wootthikanokkhan Jatuphorn. "Investigation of Morphology and Photocatalytic Activities of Electrospun Chicken Feather Keratin/PLA/TiO2/Clay Nanofibers." E3S Web of Conferences 141 (2020): 01003. http://dx.doi.org/10.1051/e3sconf/202014101003.
Full textAbstract:
This research has focused on the fabrication of electro spun-keratin base composite nanofiber, in order to develop the organic dye removal filters. The filters were prepared from a keratin-base material, which was extracted from chicken feathers. A biodegradable polymer including Poly (lactic acid) was blended into keratin to improve fibre process-ability. Titanium dioxide (anatase) and clay (Na-montmorillonite) were mixed into the PLA/Keratin blended solution prior to fabrication into non-woven fibre using the electro-spinning process. The objective of this research was to study the effect of TiO2 and clay on the process-ability, the morphology, and the filter efficiency (methylene blue removal) of the fibres. SEM images showed the morphology of small PLA/Keratin/clay-base fibres. SEM-scan mapping EDX technique showed a good dispersion of keratin, clay and TiO2 along the fibres. XRD pattern also showed the existence of PLA, keratin and TiO2. But the peak of clay was not strong enough. However, the evidence of clay was clearly shown by SEM-EDX technique as reported above. The capability to remove organic dye (methylene blue) was investigated by using UV-Vis spectrophotometer technique. From all of our results, it can be concluded that PLA/Keratin/TiO2/clay is an effective filter for the removal of organic dye from wastewater.
7
Andjelkovic, Milena, Aleksandra Buha Djordjevic, Evica Antonijevic, Biljana Antonijevic, Momcilo Stanic, Jelena Kotur-Stevuljevic, Vesna Spasojevic-Kalimanovska, et al. "Toxic Effect of Acute Cadmium and Lead Exposure in Rat Blood, Liver, and Kidney." International Journal of Environmental Research and Public Health 16, no. 2 (January 18, 2019): 274. http://dx.doi.org/10.3390/ijerph16020274.
Full textAbstract:
Background: Cadmium and lead are widespread and non-biodegradable pollutants of great concern to human health. In real life scenarios, we are exposed to mixtures of chemicals rather than single chemicals, and it is therefore of paramount importance to assess their toxicity. In this study, we investigated the toxicity of Cd and Pb alone and as a mixture in an animal model of acute exposure. Methods: Experimental groups received a single treatment of aqueous solution of Cd-chloride (15 and 30 mg/kg body weight (b.w.) and Pb-acetate (150 mg/kg b.w.), while the mixture group received 15 mg Cd/kg b.w. and 150 mg Pb/kg b.w. Toxic effects of individual metals and their mixture were investigated on hematological and biochemical parameters, and the redox status in the plasma, liver, and kidneys of treated Wistar rats. Results: Tissue-specific changes were recorded in various parameters of oxidative damage, while the accumulation of metals in tissues accompanied the disturbances of both hematological and biochemical parameters. It was observed that the level of toxic metals in tissues had a different distribution pattern after mixture and single exposure. Conclusions: Comprehensive observations suggest that exposure to Cd and Pb mixtures produces more pronounced effects compared to the response observed after exposure to single metal solutions. However, further research is needed to confirm toxicokinetic or toxicodynamic interactions between these two toxic metals in the organisms.
8
Choi, Yoon Jeong, Mi Sook Kim, and In Sup Noh. "Tissue Regeneration of a Hybrid Vascular Graft Composed of Biodegradable Layers and Non-Biodegradable Layer by Static and Pulsatile Flows." Key Engineering Materials 342-343 (July 2007): 61–64. http://dx.doi.org/10.4028/www.scientific.net/kem.342-343.61.
Full textAbstract:
Clinical applications of expanded polytetrafluoroethylene (ePTFE) as a small diameter graft have been limited due to its limited patency rates, even though its demands are high. After fabricating the biodegradable PLGA layers on both the inside and outside of ePTFE, long-term in vitro smooth muscle cell culture was performed on the luminal scaffold surface. The fabricated hybrid ePTFE scaffolds were designed to have three distinctive layers and porous structures in the biodegradable layers generated by gas-foaming of the ammonium bicarbonate porogens, i.e. two layers of poly(lactide-co-glycolide) (PLGA) as biodegradable layers for tissue engineering and an ePTFE layer in the middle as a non-biodegradable layer. We evaluated the regenerated vascular tissues after applying either static or pulstile flow on a smooth muscle cells-seeded hybrid scaffold. Analysis of the engineered tissues was performed with SEM for morphological observation and H&E staining for observation of tissue development dependent upon a mode of culture system, flow patterns and scaffold species.
9
Kandala, Bala Subramanya Pavan Kumar, Guangqi Zhang, Tracy M. Hopkins, Xiaoxian An, Sarah K. Pixley, and Vesselin Shanov. "In Vitro and In Vivo Testing of Zinc as a Biodegradable Material for Stents Fabricated by Photo-Chemical Etching." Applied Sciences 9, no. 21 (October 24, 2019): 4503. http://dx.doi.org/10.3390/app9214503.
Full textAbstract:
There is an increasing interest in biodegradable metal implants made from magnesium (Mg), iron (Fe), zinc (Zn) and their alloys because they are well tolerated in vivo and have mechanical properties that approach those of non-degradable metals. In particular, Zn and its alloys show the potential to be the next generation of biodegradable materials for medical implants. However, Zn has not been as well-studied as Mg, especially for stent applications. Manufacturing stents by laser cutting has become an industry standard. Nevertheless, the use of this approach with Zn faces some challenges, such as generating thermal stress, dross sticking on the device, surface oxidation, and the need for expensive thin-walled Zn tubing and post-treatment. All of these challenges motivated us to employ photo-chemical etching for fabricating different designs of Zn (99.95% pure) stents. The stents were constructed with different strut patterns, made by photo-chemical etching, and mechanically tested to evaluate radial forces. Stents with rhombus design patterns showed a promising 0.167N/mm radial force, which was comparable to Mg-based stents. In vitro studies were conducted with uncoated Zn stents as control and Parylene C-coated Zn stents to determine corrosion rates. The Parylene C coating reduced the corrosion rate by 50% compared to uncoated stents. In vivo studies were carried out by implanting photo-chemically etched, uncoated Zn stent segments subcutaneously in a C57BL/6 mice model. Histological analyses provided favorable data about the surrounding tissue status, as well as nerve and blood vessel responses near the implant, providing insights into the in vivo degradation of the metal struts. All of these experiments confirmed that Zn has the potential for use in biodegradable stent applications.
10
Ren, Xiaolong, Peng Zhang, Xiaoli Liu, Shahzad Ali, Xiaoli Chen, and Zhikuan Jia. "Impacts of different mulching patterns in rainfall-harvesting planting on soil water and spring corn growth development in semihumid regions of China." Soil Research 55, no. 3 (2017): 285. http://dx.doi.org/10.1071/sr16127.
Full textAbstract:
Rain-harvesting planting can improve crop biomass and enhance precipitation use efficiency in rainfed semiarid areas. In this study, field trials were conducted during summer 2007–2010 to determine the impacts of different mulching patterns in rainfall harvesting planting on spring corn growth and development in a typical semihumid dryland farming area of the Loess Plateau in China, which is characterised by spring droughts. Rain-harvesting ridges and planting furrows were mulched with 8% biodegradable film (RCSB), liquid film (RCSL), or not mulched (RCSN), and bare land drilling without mulching served as the control (CF). We found that the rain-harvesting effects of ridges and the evaporation-inhibiting and moisture-conserving effects of mulching materials during the spring corn growing season significantly increased water storage in the 0–100cm soil layer (P<0.05) compared with CF, where mulching was more beneficial than the non-mulching treatments. In the 100–200cm soil layers, there were no significant effects (P>0.05) of the treatments on water storage. During 2007–2010, the average plant height increased by 26.6%, 15.4%, and 11.1% under RCSB, RCSL, and RCSN relative to CF respectively, whereas the per plant biomass increased by 26.6%, 15.4%, and 11.1% under these treatments, and the grain yield increased by 32.3%, 17.5%, and 15.0%. Therefore, in the semihumid dryland farming areas of the Loess Plateau, rain-harvesting planting greatly increased the growth, development, and dry matter accumulation by spring corn, thereby enhancing its biomass yield, whereas the plastic-covered ridges and furrows mulched with biodegradable films substantially increased the yield-enhancing effects.
Dissertations / Theses on the topic "Non-biodegradable pattern"
1
Rutto, Hilary Kiplimo. "Urea-based moulding compounds for investment casting." Thesis, 2007. http://hdl.handle.net/2263/24620.
Full textAbstract:
Conventional urea-based moulding compounds for investment casting patterns are manufactured using a slow “cooking” process. Nowadays in industrial processes the use of a faster process is highly recommended to increase throughput levels. At the same time, for quality control purposes, the requirements of an investment caster must be met. This study is therefore focused on: - Finding the appropriate conventional process and conditions to prepare urea-based investment casting moulding compounds.
- Optimising the composition variables to meet the mechanical, thermal, surface, flow and cost properties needed in investment casting.
- Characterising the moulding compounds to meet the requirements of an investment caster by comparing them with an industrial, “cooked” urea-based compound.
- Increasing polymer content produced weaker but tougher moulding compounds.
- Increasing wax content improved the strength and stiffness but gave compounds that were less tough.
- Two-way Analysis of Variance (ANOVA) indicated significant polymer-wax interactions.
Thesis (PhD)--University of Pretoria, 2011.
Chemical Engineering
unrestricted
Book chapters on the topic "Non-biodegradable pattern"
1
Alima, N., R. Snooks, and J. McCormack. "Bio Scaffolds." In Proceedings of the 2021 DigitalFUTURES, 316–29. Singapore: Springer Singapore, 2021. http://dx.doi.org/10.1007/978-981-16-5983-6_29.
Full textAbstract:
Abstract‘Bio Scaffolds’ explores a series of design tectonics that emerge from a co-creation between human, machine and natural intelligences. This research establishes an integral connection between form and materiality by enabling biological materials to become a co-creator within the design and fabrication process. In this research paper, we explore a hybrid between architectural aesthetics and biological agency by choreographing natural growth through form. ‘Bio Scaffolds’ explores a series of 3D printed biodegradable scaffolds that orchestrate both Mycelia growth and degradation through form. A robotic arm is introduced into the system that can respond to the organism’s natural behavior by injecting additional Mycelium culture into a series of sacrificial frameworks. Equipped with computer vision systems, feedback controls, scanning processes and a multi-functional end-effector, the machine tends to nature by reacting to its patterns of growth, moisture, and color variation. Using this cybernetic intelligence, developed between human, machine, and Mycelium, our intention is to generate unexpected structural and morphological forms that are represented via a series of 3D printed Mycelium enclosures. ‘Bio Scaffolds’ explores an interplay between biological and computational complexity through non anthropocentric micro habitats.
Conference papers on the topic "Non-biodegradable pattern"
1
Yayoglu, Yahya E., Nathan D. Gallant, Ryan Toomey, and Nathan B. Crane. "Effects of Laser Ablation Parameters to Pattern High Purity Magnesium Surfaces." In ASME 2019 International Mechanical Engineering Congress and Exposition. American Society of Mechanical Engineers, 2019. http://dx.doi.org/10.1115/imece2019-11810.
Full textAbstract:
Abstract Magnesium and magnesium-based alloys have relatively low weight and desirable mechanical properties for many applications in multiple industries including aerospace and automotive. In the past decade, due to its biocompatible nature, the medical field has expressed significant interest in magnesium for biodegradable implant applications. However, utilization of magnesium-based alloys in surgical implant applications is strictly limited by magnesium’s high vulnerability to corrosion causing premature disintegration inside the human body. Hydrophobic (non-wetting) behavior of metal surfaces has been proven to be beneficial for corrosion protection in academic literature. One way of achieving hydrophobic and super-hydrophobic surfaces on metal surfaces without using non-biocompatible coatings is creating uniform microstructures that would alter the wetting characteristics of the surface. This work focuses on creating uniform pillar shaped micro-patterns on smooth pure magnesium surfaces by utilizing a picosecond laser (λ = 355 nm). The study reports the effects of average laser power, partial laser beam overlap and number of laser scans on the height, steepness, roughness of the resultant micro-pillars. Information gathered from this study could be useful in creating more complex or finer micro-structures on magnesium and its alloys to alter their wetting or corrosion characteristics using laser ablation which is a fast, repeatable and an un-convoluted process.
2
Nawik, Adisak, Kyle Taylor, and Reza Barati Ghahfarokhi. "An Environmentally Friendly Alternative for the Conventional Acids Used in Acid Fracturing of Carbonate Reservoirs." In ASME 2016 35th International Conference on Ocean, Offshore and Arctic Engineering. American Society of Mechanical Engineers, 2016. http://dx.doi.org/10.1115/omae2016-54487.
Full textAbstract:
The acid fracturing techniques developed for well stimulation purposes have been applied to maximize oil production while bypassing the near wellbore damage. Commonly used acids such as hydrochloric acid (HCl) and hydrofluoric acid (HF) damage equipment, are not environmentally friendly and, most importantly, they are harmful to oil field workers. Moreover, transportation of such fluids to the well-head and neutralization of the flow-back products is costly. The Ultra Series FF-01 is an environmentally- and equipment-friendly alternative to the commercially available products. The Ultra Series FF-01 is very acidic, its pH is less than 1, and has a slower reaction rate compared to the HCl. It can work up to 72 times longer than hydrochloric acid. Most importantly, it is biodegradable and is non-corrosive to the field equipment. Acid conductivity measurement tests were designed to simulate acid fracturing for comparing the performance of acid fracturing fluids. The main objectives of this study is to compare the ability of Ultra Series FF-01 samples in etching the surface of carbonate rocks by measuring the conductivity of the simulated etched fracture. The two acid fracturing fluids that are used in these experiments are the Ultra series FF-01 and a conventional 15% hydrochloric acid with the iron control agent, non-emulsifier, and corrosion inhibitors. The injection rate is at 100 mL/min and the total time of injection is 1 hr. Experiments were performed on carbonate rocks at 40° C and 70° C and the leak-off pressure was set to be 100 psi lower than the overall pressure. Then the conductivity was measured at different closure stress after the injection time is complete. Conductivity after etching by the Ultra series FF-01 was significantly improved compared to that obtained with 15% hydrochloric acid with additives when the leak off was set at 100 psi lower than the system pressure for all values of closure stress. It was very evident from the difference in the etching patterns between the two fluids. The etching pattern that was created by the Ultra series FF-01 was in the shape of human veins, visible and connected. In contrast, the surface of the core samples that were etched by 15% hydrochloric acid with additive were bouncy but shallow, producing inferior conductivity. In addition, the performance of the Ultra series FF-01 was slightly better than 15% hydrochloric acid with additives when the leak off pressure was set at 50 psi lower than the system pressure for all closure stress pressure except for 1000 psi.
3
Mehta, Bhavin V., and Robert J. Setlock. "Improved Prosthetic Bone Implants." In ASME 2003 International Mechanical Engineering Congress and Exposition. ASMEDC, 2003. http://dx.doi.org/10.1115/imece2003-43048.
Full textAbstract:
An improved method for manufacturing prosthetic bones is examined. We are developing a new improved method for designing and manufacturing prosthetic bones that have a porous interior core covered by a solid outer shell, more closely matching the morphology of natural bone. The new method is compatible with a wide variety of materials, including polymers, metals, composites, and biodegradable scaffold materials. Use of biodegradable scaffold material holds the potential for eventual bone regeneration within and throughout the prosthesis. Regardless of the material selection, this improved type of prosthesis is expected to more closely mimic the overall material and structural properties of natural bone, including shape, strength, weight, and weight distribution. By fabricating prosthetic bones that duplicate the material and structural properties of natural bone, implants could be made to operate as precision replacements, feeling and functioning exactly like natural bone. In addition to improving patient comfort, these new prostheses are expected to reduce the occurrence of unnatural secondary wear patterns caused by current style prosthetic bones that function in unnatural fashions due to their non-matching material and structural properties.