scholarly journals Sustainable mechanochemical synthesis of β-cyclodextrin polymers by twin screw extrusion

2021 ◽  
Author(s):  
Alberto Rubin Pedrazzo ◽  
Francesco Trotta ◽  
Gjylije Hoti ◽  
Federico Cesano ◽  
Marco Zanetti
Keyword(s):  
Continuous Process ◽  
Three Dimensional ◽  
Chemical Reactor ◽  
Batch Process ◽  
Cyclodextrin Nanosponges ◽  
Twin Screw ◽  
Cyclodextrin Polymers ◽  
The Many ◽  
Drive And Control ◽  
And Control

AbstractCyclodextrin nanosponges (CD-NS) are cross-linked cyclodextrin polymers characterized by a nanostructured three-dimensional network. CD-NSs in the last years found many different applications in the pharmaceutical field for the controlled release of drugs and for the absorption of undesired substances from physiological media, food, and wastewater. Most of CD-NS syntheses involve the solubilization of the chosen CD in closed batch, using a suitable organic polar aprotic liquid, which may affect potential environmental or biomedical applications. Since the research is now moving towards more sustainable approaches, new and greener syntheses of CD-NS are now being developed. Here, it is reported a new eco-friendly and efficient synthesis of nanosponges through mechanochemistry. Mechanochemistry involves the application of mechanical forces to drive and control chemical reactions by transferring energy to chemical bonds. The mechanochemical approach involves the use of a twin-screw extruder (TSE) as a chemical reactor: TSE are capable of fine temperature control and, furthermore, TS Extrusion is a continuous process and not a batch process. Among the many available CD-NS syntheses, we tested our solvent-free approach on a β-CD/citric acid (CA) system. Moreover, using TSE, the same polymer was obtained in a considerably shorter time. The so obtained NSs were used for the adsorption and removal of probe molecules, in comparison with NSs prepared by cross-linking β-CD with CA in batch. Graphical Abstract

Moving Mode of Wireless Capsule Endoscopy Driven by External Magnetic Field

2014 ◽  
Vol 678 ◽  
pp. 318-321
Author(s):  
Gui Lian Shi ◽  
Fu Li Ye
Keyword(s):  
Magnetic Field ◽  
Dynamical Systems ◽  
External Magnetic Field ◽  
Human Body ◽  
Capsule Endoscopy ◽  
Three Dimensional ◽  
Wireless Capsule Endoscopy ◽  
Drive And Control ◽  
And Control ◽  
Wireless Capsule

The existing dynamical systems of wireless capsule endoscopy are studied and analyzed. Based on the shortcomings presented in paper, a novel driving method is proposed. That is driving the wireless capsule endoscopy with three-dimensional orthotropic magnetic field outside the human body, and the resultant magnetic field can be obtained and adjusted through the electric current flowing in three coils orthogonal to each other. This paper focuses on the analysis of complex moving mode of wireless capsule endoscopy, and the result is very important to the design of drive and control circuit.

Computers for data, control and simulation

1988 ◽  
Vol 46 ◽  
pp. 920-921
Author(s):  
David C. Joy
Keyword(s):  
Personal Computers ◽  
Monitoring And Control ◽  
Data Logging ◽  
Data Logger ◽  
Operational Conditions ◽  
Data Control ◽  
The Many ◽  
And Control

Personal computers (PCs) are a powerful resource in the EM Laboratory, both as a means of automating the monitoring and control of microscopes, and as a tool for quantifying the interpretation of data. Not only is a PC more versatile than a piece of dedicated data logging equipment, but it is also substantially cheaper. In this tutorial the practical principles of using a PC for these types of activities will be discussed.The PC can form the basis of a system to measure, display, record and store the many parameters which characterize the operational conditions of the EM. In this mode it is operating as a data logger. The necessary first step is to find a suitable source from which to measure each of the items of interest. It is usually possible to do this without having to make permanent corrections or modifications to the EM.

Еlectric Drive and Control System of Flying saw of electricweld item

2015 ◽  
Vol 19 (95) ◽  
pp. 50-53
Author(s):  
Aleksej A. Kravcov ◽  
◽  
Leonid G. Limonov ◽  
Valerij V. Sinelnikov ◽  
Stanislav V. Potapov
Keyword(s):  
Control System ◽  
Drive And Control ◽  
And Control

scholarly journals Three-Dimensional Thematic Map Imaging of the Yacht Port on the Example of the Polish National Sailing Centre Marina in Gdańsk

2021 ◽  
Vol 11 (15) ◽  
pp. 7016
Author(s):  
Pawel S. Dabrowski ◽  
Cezary Specht ◽  
Mariusz Specht ◽  
Artur Makar
Keyword(s):  
Spatial Data ◽  
Convex Surface ◽  
Dimensional Space ◽  
Three Dimensional ◽  
Future Research ◽  
Two Dimensional ◽  
Thematic Maps ◽  
Research Directions ◽  
Future Research Directions ◽  
The Many

The theory of cartographic projections is a tool which can present the convex surface of the Earth on the plane. Of the many types of maps, thematic maps perform an important function due to the wide possibilities of adapting their content to current needs. The limitation of classic maps is their two-dimensional nature. In the era of rapidly growing methods of mass acquisition of spatial data, the use of flat images is often not enough to reveal the level of complexity of certain objects. In this case, it is necessary to use visualization in three-dimensional space. The motivation to conduct the study was the use of cartographic projections methods, spatial transformations, and the possibilities offered by thematic maps to create thematic three-dimensional map imaging (T3DMI). The authors presented a practical verification of the adopted methodology to create a T3DMI visualization of the marina of the National Sailing Centre of the Gdańsk University of Physical Education and Sport (Poland). The profiled characteristics of the object were used to emphasize the key elements of its function. The results confirmed the increase in the interpretative capabilities of the T3DMI method, relative to classic two-dimensional maps. Additionally, the study suggested future research directions of the presented solution.

scholarly journals Biodegradation of Poly(Lactic Acid) Biocomposites under Controlled Composting Conditions and Freshwater Biotope

Polymers ◽  
2021 ◽  
Vol 13 (4) ◽  
pp. 594
Author(s):  
Pavel Brdlík ◽  
Martin Borůvka ◽  
Luboš Běhálek ◽  
Petr Lenfeld
Keyword(s):  
Degradation Rate ◽  
Poly Lactic Acid ◽  
Screw Extruder ◽  
Flat Film ◽  
Twin Screw ◽  
Acetyl Tributyl Citrate ◽  
And Control ◽  
Aerobic Biodegradability ◽  
Qualitative Analyses

The influence of additives such as natural-based plasticiser acetyl tributyl citrate (ATBC), CaCO3 and lignin-coated cellulose nanocrystals (L-CNC) on the biodegradation of polylactic acid (PLA) biocomposites was studied by monitoring microbial metabolic activity through respirometry. Ternary biocomposites and control samples were processed by a twin-screw extruder equipped with a flat film die. Commonly available compost was used for the determination of the ultimate aerobic biodegradability of PLA biocomposites under controlled composting conditions (ISO 14855-1). In addition, the hydro-degradability of prepared films in a freshwater biotope was analysed. To determine the efficiency of hydro-degradation, qualitative analyses (SEM, DSC, TGA and FTIR) were conducted. The results showed obvious differences in the degradation rate of PLA biocomposites. The application of ATBC at 10 wt.% loading increased the biodegradation rate of PLA. The addition of 10 wt.% of CaCO3 into the plasticised PLA matrix ensured an even higher degradation rate at aerobic thermophilic composting conditions. In such samples (PLA/ATBC/CaCO3), 94% biodegradation in 60 days was observed. In contrast, neat PLA exposed to the same conditions achieved only 16% biodegradation. Slightly inhibited microorganism activity was also observed for ternary PLA biocomposites containing L-CNC (1 wt.% loading). The results of qualitative analyses of degradation in a freshwater biotope confirmed increased biodegradation potential of ternary biocomposites containing both CaCO3 and ATBC. Significant differences in the chemical and structural compositions of PLA biocomposites were found in the evaluated period of three months.

scholarly journals Special Issue: Application of Extracellular Matrix in Regenerative Medicine

2021 ◽  
Vol 11 (7) ◽  
pp. 3262
Author(s):  
Neill J. Turner
Keyword(s):  
Extracellular Matrix ◽  
Regenerative Medicine ◽  
Wound Repair ◽  
Three Dimensional ◽  
Dynamic Structure ◽  
Scaffold Material ◽  
Special Issue ◽  
Organ Regeneration ◽  
Scaffold Materials ◽  
The Many

The present Special Issue comprises a collection of articles addressing the many ways in which extracellular matrix (ECM), or its components parts, can be used in regenerative medicine applications. ECM is a dynamic structure, composed of a three-dimensional architecture of fibrous proteins, proteoglycans, and glycosaminoglycans, synthesized by the resident cells. Consequently, ECM can be considered as nature’s ideal biologic scaffold material. The articles in this Special Issue cover a range of topics from the use of ECM components to manufacture scaffold materials, understanding how changes in ECM composition can lead to the development of disease, and how decellularization techniques can be used to develop tissue-derived ECM scaffolds for whole organ regeneration and wound repair. This editorial briefly summarizes the most interesting aspects of these articles.

Exploring ‘digital placemaking’

2021 ◽  
Vol 27 (3) ◽  
pp. 573-578
Author(s):  
Germaine Halegoua ◽  
Erika Polson
Keyword(s):  
Digital Media ◽  
Sense Of Place ◽  
Media Use ◽  
Special Issue ◽  
Social Actors ◽  
Broad Framework ◽  
The Many ◽  
And Control ◽  
Connected Spaces

This brief essay introduces the special issue on the topic of ‘digital placemaking’ – a concept describing the use of digital media to create a sense of place for oneself and/or others. As a broad framework that encompasses a variety of practices used to create emotional attachments to place through digital media use, digital placemaking can be examined across a variety of domains. The concept acknowledges that, at its core, a drive to create and control a sense of place is understood as primary to how social actors identify with each other and express their identities and how communities organize to build more meaningful and connected spaces. This idea runs through the articles in the issue, exploring the many ways people use digital media, under varied conditions, to negotiate differential mobilities and become placemakers – practices that may expose or amplify preexisting inequities, exclusions, or erasures in the ways that certain populations experience digital media in place and placemaking.

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