Evaluation of microfiber release from jeans: the impact of different washing conditions

Microplastic particles are a burgeoning population crisis in the marine environment. This research examines the emission of microfibers from three different jeans (garments) during domestic washing. The jeans types, washing temperature, washing duration, spin speed, detergent types, and addition of conditioner are the main factors for this research work. The average length and diameter of the microfibers for the 100% PET jeans (jeans-P) has 7800 ± 4000 μm and 11.9±3.2 μm and for polyester/cotton jeans (jeans-PB) has 4900 ± 2200 μm 17.4±4.8 μm, respectively. The maximum microfiber released was observed in the rigorous washing treatment (90 min, 60°C, 1400 rpm, powder detergent with the presence of conditioner). The surmised number of microfibers discharged from the 1 kg wash load of jeans-P was calculated within the extent of 2300000–4900000 microfibers, and it is varied by the washing treatments.

Successful Removal of Clostridioides Difficile Spores and Pathogenic Bacteria From a Launderable Barrier Using a Commercial Laundry Process

Background: To properly clean and disinfect hospital mattresses, bed manufacturers recommend a 3- to 6-step process to remove all pathogenic bacteria. An alternative is to use a removable barrier on the mattress, which is laundered after each use. The current study was to determine efficacy of a commercial laundry process in eliminating Clostridioides difficile (C diff) spores, Mycobacterium terrae (M terrae), methicillin-resistant Staphylococcus aureus (MRSA), Pseudomonas aeruginosa (P aeruginosa), Klebsiella pneumoniae (K pneumoniae), and Escherichia coli (E coli) from a barrier. Methods: A test barrier received 3 unique microbial suspensions in separate locations, each suspension having a known quantity of specific microorganisms: C diff spores, M terrae, and a mixed suspension of MRSA, S aureus, P aeruginosa, K pneumoniae, and E coli. A wash load contained the test barrier and 11 additional ballast barriers. Various soils were spread onto the barriers to simulate heavy soiling that may occur in a wash load: Each barrier received a small amount of mixed soil, 50% received urine, 25% received blood, and 25% received a large amount of additional mixed soil. The load was laundered using 71°C (160°F) water, detergent, and chlorine bleach, with final drying at 71°C (160°F). After laundering, remaining colony-forming units (CFUs) of each microorganism were counted at the applied locations. Each test was replicated 3 times. Industry-accepted methods were used to produce suspensions, apply inoculum, and recover organisms after laundering. Results: Before laundering, test barriers contained at least 7.0 log10 cfu/mL of each microorganism distributed over 103 cm2. After laundering, in all cases, no residual CFUs were detected over the test area, resulting in greater than 6.0 log10 reductions for every organism. ( P < .05). Conclusions: Under extreme test conditions including the presence of soil, the laundry process removed all detectable pathogenic bacteria and spores from the barrier.

The mechanism of wrinkling of cotton fabric in a front-loading washer: The effect of mechanical action

In order to understand the impact of mechanical action on the wrinkling of cotton fabrics in a drum washer, fabric movement was observed and a movement index system was developed to characterize the textile motion. Results showed that spinning speed and wash load were the major factors influencing the smoothness of cotton fabrics, with p values of 0.000 and 0.032, respectively. The analysis of fabric movement illustrated that when the wash load increased, the free motion region decreased and the ratio of passive motion region increased, resulting in severe wrinkling of cotton fabric. A regression model was developed to characterize the relationship between fabric movement and smoothness. These findings help the understanding of the mechanism of wrinkling during a drum washer washing.

MIGRATING SAND WAVES OR SAND HUMPS, WITH SPECIAL REFERENCE TO INVESTIGATIONS CARRIED OUT ON THE DANISH NORTH SEA COAST

The transport of sediment by flowing water commands great interest in connection with the control of floods, land reclamation, and the construction of harbours and coast protection works. A distinction can be drawn between littoral drift in rivers and in the sea. The sediment transportation in rivers has been investigated by several authors, e.g. Shields, Meyer Peter, Kalinske, and Einstein, see (16) pp„ 769-83*+. Einstein's latest theories have given reliable results in practice (9). As pointed out by Einstein (7), there cannot be much difference, physically, between transportation of sediment in rivers and longshore drift at sea shores, apart from the littoral zone with its extremely complex conditions. In the attempt to understand the complex problem of sea shores the practice so far has been to split them up into several reaches and investigate them separately. This work has given a number of results of practical interest in connection with littoral drift and coastal protection technology, see (2), (3), (5)» (6), (11), (13), and (16). According to Einstein, Johnson and Chien (8) there exist two types of sediment load, one that bears a certain relationship with the discharge (bed-material load), and the other which does not (wash load). The result of flume study indicates that the transport rate of wash load, just as that of the bed-material load, can be calculated according to the Einstein bed-load function (9), if the instantaneous bed composition is known. On the other hand, the bedmaterial load is equally available'in the entire bed, but only the surface bed layer contains any significant amount of wash-load material. Any change of flow or of sediment supply may immediately change the composition of the wash-load material in the bed. The bed composition as determined from the instantaneous condition of the channel has no lasting significance so far as the wash load is concerned, and this makes the prediction of the wash-load rate from.the bed-load function impossible. The following deals with a mode of bed-load transportation which, as far as can be seen, takes place in large "waves" or humps. Introductorily are mentioned investigations made in the United States on migrating sand bars and sand waves in rivers, and investigations in Holland on migrating sand bars on the bottom of the sea. The major part of the paper deal with migrating sand humps along the North Sea coast of the peninsula of Jutland, Denmark, see Fig. 3.