polyethylene tube
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2022 ◽  
Vol 9 ◽  
Author(s):  
Zhengdian Xu ◽  
Hong Li ◽  
Yue Jiang ◽  
Qingjiang Xiang ◽  
Pan Tang

To solve the problems of higher energy consumption and lower intelligence of traditional hard hose travelers, a new hard hose traveler with the function of electric drive and self-propelled is developed in this paper. The operational energy consumption of a reel and a polyethylene tube is an important part of hard-hose traveler energy consumption. In this paper, based on the JP50-180 hard hose traveler, the required pulling force and energy consumption at the reel and tube operation are theoretically and experimentally obtained. The aforementioned provides support for reducing energy consumption in the future. The influencing factor that affects the energy consumption of the reel rotation is the tube length, and the influencing factors that affect the energy consumption of the tube sliding are the ground slope, soil moisture content, and tube length. A calculation model for the dynamic change of the pulling force and energy consumption of the reel and tube operation is proposed in this study. Through theoretical analysis, maximum pulling tension and cumulative energy consumption requirements for the for reel rotation are 278.6 N and 15120.83 J, respectively. Furthermore, the requirements for the tube sliding are 1372.86 N and 123,456.96 J. Through test analysis, the maximum pulling tension for the tube sliding is between 1258.3 N and 1773.3 N, while the maximum pulling tension for reel rotation is 285.05 N. Under the same influencing factors, the deviation rates between theoretical and testable energy consumption for the reel rotation and tube sliding are 2.3 and 8.3%, respectively. The pulling force and cumulative energy consumption required for the reel rotation and tube sliding both increase with an increase in their influencing factors. The operating costs of the tube one-time unrolled are approximately 0.0185 CNY. Combined with the mobile resistance of the electric tracked vehicle, the power configuration of this new hard hose traveler is provided by two servo motors with a power of 5500 W each.


2021 ◽  
Vol 11 (41) ◽  
pp. 216-223
Author(s):  
Nirmal Chandra Sukul ◽  
Indrani Chakraborty ◽  
Anirban Sukul ◽  
Rathin Chakravarty

Background: A common practice is to give homeopathic medication to nursing mothers to treat their children, assuming that the drug will be conveyed by the milk. In the case of conventional treatment, the drug molecules are indeed passed on from the mother to her breastfed infant. However, high dilutions (HD) above 12 cH, i.e., over Avogadro’s number, are traditionally held to lack any molecule from the starting material. If that is the case, then, does medication taken by the mother actually reach the child? To answer to that question, we developed plant models and demonstrated the transfer of HD effects between 2 groups of plants. Aims: To demonstrate the transfer of HD effects in an animal model in a much shorter time. Methods: Two batches of toads were respectively placed in two beakers, one containing Nux vomica 200 cH diluted with water 1:500 (direct treatment), and the other the same amount of distilled water were connected by cotton thread soaked in water and encased in a polyethylene tube (connected group); a third batch of toads (control) were placed in a beaker with 90% ethanol diluted with distilled water 1:500; all the animals were left 30 minutes, and then transferred to 3 independent beakers containing 209 mM ethanol. Every 10 minutes, the motionless toads were removed from the beakers, and placed on supine position, failure to recover the upright position after 60 sec was considered as loss of the righting reflex (RR). The experiment was replicated using large adult toads. Results: The percentage of toads losing the RR increased with the time of exposure to 209 mM ethanol in the 3 groups of toads. Significant difference in the percentage distribution was found between the control and the direct treatment and connected groups on χ2 test (p < 0.001, p < 0.01, respectively), whereby the latter required much longer time to lose the RR, and did not differed between them. In the experiment with large adult toads, the control group lost RR in 78 min, whereas the 2 treated groups did not lose RR even after 240 min. Conclusion: Nux-v 200 cH countered the hypnotic effect of alcohol in young toads, and this effect was transferred through capillary water in the cotton thread, supporting the transfer of the effect of homeopathic medication from mother to child.


2021 ◽  
Vol 48 (4) ◽  
pp. 367-375
Author(s):  
Haeni Kim ◽  
Howon Park ◽  
Juhyun Lee ◽  
Hyunwoo Seo

This study evaluated the fluoride release of alkasite restorative material (ARM) and giomer penetrating the dentin adhesive layer. Twenty specimens were prepared for each restorative material, and dentin adhesive with uniform thickness was applied to half of them. The prepared specimens were placed in a polyethylene tube containing 2.0 mL of deionized water and deposited in a 37.0°C water bath for the study duration. The amount of fluoride release was measured on the 1st, 3rd, 7th, 14th, 21st, and 28th days after deposition. The dentin adhesive applied to the ARM and giomer could not completely block the fluoride release; however, it significantly reduced its amount. The cumulative amount of fluoride release of the ARM after 28 days was higher than that of the giomer regardless of the application of dentin adhesive.


Author(s):  
Rory Verhagen ◽  
Benjamin J. Tscharke ◽  
Joseph Clokey ◽  
Cobus Gerber ◽  
Maulik Ghetia ◽  
...  

2020 ◽  
pp. 004051752097017
Author(s):  
Małgorzata Cieślak ◽  
Ewa Gromadzińska ◽  
Irena Kamińska ◽  
Ewa Witczak ◽  
Katarzyna Śledzińska

A long-term static position causes inter alia hypoxia, poor blood circulation, slowing down of the metabolism, and problems in air and heat transport, which in consequence lead to the occurrence of bedsores. In the design of seats and mattresses for people with impaired mobility, advanced textile and composite materials should be used to improve safety and comfort. This functionality can be obtained using spatial textile materials. The aim of the research was to assess the impact of two unmodified woven relief structures I.0 and II.0 made of different yarns and ones modified by inserting linear elements (1: braided round tape and 2: polyethylene tube) to their rib tunnel on the heat transport and on the pressure distribution under loading of 0.5, 1, and 2 N. Element 1 lowers the value of average pressure on the fabrics I.1 and II.1, respectively, by 6.9% and 3.5% at the lowest loading and by 9.8% and 4.6% at the highest loading. For fabric II.2 with element 2, the decrease is of 10.4% and 8.4%, respectively. The thermal conductivity values increase by 8.8%, 9.4%, and 40.1%, respectively for I.1, II.1, and II.2. The pressure distribution and thermal characteristic of the fabrics depend on the type of yarn, the structure of ribs, and the linear element and its fit to the rib tunnel.


2020 ◽  
pp. 030936462095851
Author(s):  
Natali Olaya Mira ◽  
Carolina Viloria Barragán ◽  
Jesus Alberto Plata

Background: Mechanical behavior is difficult to monitor in experimental environments, usually because of geometric or technology implementation limitations. Nevertheless, thermography has been shown to overcome these issues. Objectives: The aim of this study was to evaluate four types of assemblies between a Jaipur foot and a polyethylene tube using infrared thermography in order to find the best mechanical configuration in terms of thermal behavior. Study Design: Mechanical testing. Technique: An infrared camera captured short videos every 5 min over 10 h in six different positions (three in the back and three in front of the Jaipur foot) around a prosthesis subjected to repetitive stresses (axial force 980 N) simulating kinematic variables like joint angles. We established a region of interest around the foot–ankle assemblies and calculated maximum temperatures and thermographic indices. Results: In this study, the best foot–ankle assembly used epoxy adhesive because it presented the lowest temperature in the six positions and the lowest thermal index. Conclusions: Thermographic techniques can be used to study mechanical behaviors in complex experimental situations.


Doklady BGUIR ◽  
2020 ◽  
Vol 18 (6) ◽  
pp. 75-80
Author(s):  
N. A. Pevneva ◽  
A. A. Kopshai ◽  
A. L. Gurskii

To determine the dielectric permittivity of materials in a wide frequency range with the automation of measurements and the necessary accuracy, measuring cells have been created to ensure the simplicity of the design of the waveguide path. In order to obtain information about the suitability of measuring cells based on irregular SHF waveguides for estimation of dielectric parameters of materials, we simulated the structure of electromagnetic field in the system consisting of two irregular waveguides and waveguide chamber placed between them using a three-dimensional electrodynamic simulation in Ansoft HFSS package environment. The distribution of the electric field was simulated when an empty polyethylene tube, a rod of fluoroplastic and a rod of textolite are placed in the measuring cell. It was demonstrated that high order modes fade out in irregular waveguide and do not affect the precision of obtained results, and significant edge effects were not detected. It allows one to utilize measuring cells based on irregular waveguides together with a scalar or vector network analyzer and using the partial filling of the waveguide method or the modified Nicholson – Ross – Weir method for measurements of dielectric permittivity  of materials. The results of modeling the dependence of the amplitude and phase of the reflection coefficient of the textolite and fluoroplastic on the frequency in Ansoft HFSS environment are given. The simulation results are compared with the results obtained experimentally. The frequency dependencies of  were obtained experimentally for test materials – textolite and fluoroplastic – in the frequency range of 25,95–37,50 GHz. The experimental data are in satisfactory agreement with the results of theoretical calculations and do not go beyond the boundaries specified by the measurement uncertainty.


2020 ◽  
Vol 18 ◽  
Author(s):  
Alireza Partoazar ◽  
Fatemeh Rahmani Bideskan ◽  
Nasrin Takzaree ◽  
Mohammad Mehdi Soltan Dallal

Background: Infectious diseases, whether intracellular or extracellular infections, biofilm-mediated, or medical device- associated have always been a global problem in public health causing millions of deaths each year. The aim of this study was to evaluate the antibiofilm activity of ZnO/ZeoNC against K. pneumoniae along with biocompatibility of nanocomposite in vivo model. Objective: The formation of biofilm by K. pneumoniae in the catheter-associated urinary tract causes a nosocomial infection. In this regard, antimicrobial nanomaterials have emerged as potent effective agents against biofilm formation. Nevertheless, nanoparticles have already been a challenge with possible side effects such as inflammation. The ZnO/ZeoNC may exhibit anti-biofilm property with minimal adverse effects. Methods: The biofilm formation of K. pneumoniae strains was exposed to ZnO/ZeoNC and then SEM imaging was performed for morphological investigation of bacteria in biofilm state. The quantity of mice tissue response to ZnO/ZeoNC embedded polyethylene tube also analyzed on the tissue of mice during the 30-day experiment. Results: The results of this study showed that ZnO/ZeoNC has the significant antibiofilm activity against K. pneumoniae strains in its sublethal doses. The ZnO/ZeoNC also caused deformation on K. pneumoniae biofilm. In addition, ZnO/ZeoNC also reduced inflammatory response in cell tissue of rats subjected to polyethylene tube. Conclusion: ZnO/ZeoNC can be used potentially against the infections due to K. pneumonia biofilm without irritability on the biotic surface such as urinary tract.


2020 ◽  
Vol 3 (02) ◽  
pp. 21-33
Author(s):  
Daniel Soleymani ◽  
Sahar Zargari ◽  
Ali Faghihi-Zarandi

  In this work, a robust method was developed for the determination of mercury in nail and hair in petrochemical workers. By experimental procedure, 100 mg of hair and nail of workers was prepared as a powder which dried in the oven for 20 min at 95oC.  20 mg of hair or nail samples added to reagents (HNO3/H2O2; 5:1) in polyethylene tube (PET) of microwave digestion and the mercury in resulting solution was removed with silver nanoparticles pasted on multi-walled carbon nanotubes (Ag-MWCNTs) which were placed in head space of separator. The mercury vapor was removed by Ag-MWCNTs as the headspace sorbent trap (HSST) under hood conditions. Finally, the mercury was online determined by cold vapor atomic absorption spectrometry after the heat process at 250oC in the presence of Ar gas. The capacity adsorptions of Ag-MWCNTs and MWCNTs for mercury removal were obtained 205.4 mg g-1 and 63.7 mg g-1, respectively.


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