Influence of the Processing Mode of Nonwoven Needle-Punched Materials on Air Filtration

The achieved accuracy in the electrochemical performance of understatement with a depth of 18 mcm with a tolerance of 4.5 mcm in a flow-through interelectrode channel is studied. The primary error of the size. The allowed absolute and relative errors of processing mode parameters are set. Keywords: UNDERSTATEMENT, ELECTROCHEMICAL MACHINING, ERROR, PRECISION SIZE, TOLERANCE, PROCESSING MODE. [email protected]

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Features of rolled billets milling and methods for its improvement

10.36652/0042-4633-2020-5-67-71 ◽

2020 ◽

pp. 67-71

Author(s):

M.Z. Pevzner ◽

S.A. Smertin

Keyword(s):

Surface Relief ◽

Regression Dependence ◽

Processing Mode ◽

Hot Rolled

A model of the formation of the surface relief hiring milling of rolled billets and a method for selecting the milling mode based determining the regression dependence of the resulting relief on the processing mode are proposed. It is shown that the regulation of the processing mode as the tool wears out allows to increase the milling resource and productivity. Keywords hot rolled strips, milling, rolling, relic resistance, mill. [email protected]

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Air filtration improvement of konjac glucomannan-based aerogel air filters through physical structure design

International Journal of Low-Carbon Technologies ◽

10.1093/ijlct/ctab011 ◽

2021 ◽

Author(s):

Hong Qian ◽

Ying Fang ◽

Kao Wu ◽

Hao Wang ◽

Bin Li ◽

...

Keyword(s):

Pore Size Distribution ◽

Pore Size ◽

Size Distribution ◽

Surface Area ◽

Physical Structure ◽

Structure Design ◽

Air Filtration ◽

Air Filters ◽

Air Filter ◽

Purification Time

Abstract This study presents two methods to improve the air filtration performance of konjac glucomannan (KGM)-based aerogel air filters through physical structure design by changing the pore-size distribution and the surface area, using an air purifier. Results indicated that KGM-based aerogels had a comparable filtration effect with the commercial air filter with a longer purification time. This purification time could be shortened by over 50%, by changing the pore-size distribution from large size to small size or increase the surface area with the fold structure. This should boost the development of polysaccharide-based aerogel used as the air filter.

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Awareness of aerosol-related transmission of COVID-19 among the dentists of Nepal

BDJ Open ◽

10.1038/s41405-021-00079-0 ◽

2021 ◽

Vol 7 (1) ◽

Author(s):

Nashib Pandey ◽

Buddha Bahadur Basnet ◽

Sushmit Koju ◽

Anju Khapung ◽

Alka Gupta

Keyword(s):

Social Sciences ◽

Particle Size ◽

High Efficiency ◽

Emergency Services ◽

Uv Light ◽

Ventilation System ◽

Age Groups ◽

Air Filtration ◽

Online Questionnaire ◽

Dental Practitioners

Abstract Objective To access the awareness of dental practitioners of Nepal towards COVID-19 transmission through aerosols. Materials and methods The study involved 384 dentists from all over Nepal and was conducted for a period of 3 months. A self-reported online questionnaire was developed using Google forms and the link was shared. It emphasized the awareness related to the aerosol and ventilation system in their daily practices was prepared. The data were analyzed in Statistical Package for Social Sciences version 20.0 software. Results The majority of participants were female 52.9% (n = 203) and within the age groups of <30 years 57% (n = 219). Participants from Bagmati Province were 60.4% (n = 232), with least from Sudurpaschim Province 0.5% (n = 2). 60% of participants provided only emergency services during the COVID-19 pandemic and few (7%) provided consultations via telephone. The current ventilation system used was a well-ventilated room with open windows 65.4% (n = 251). However, 52.8% (n = 203) preferred specialized operatory incorporating high-efficiency particulate air (HEPA) filters and ultraviolet (UV) light. More than 60% of respondents were unaware of the particle size of the aerosol. Conclusions The obtained results signify the need for the proper ventilation system with appropriate air filtration systems in dental clinical setups.

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