Behavior of ECC/Concrete Layered Repair System Under Drying Shrinkage Conditions / Das Verhalten eines geschichteten Instandsetzungssystems aus ECC und Beton unter der Einwirkung von Trocknungsschwinden

2006 ◽  
Vol 12 (2) ◽  
pp. 143-160 ◽  
Author(s):  
M. Li ◽  
V. C. Li
Author(s):  
B. Thompson ◽  
N. Sculov ◽  
R.E. Crang

The use of co-polymerized glutaraldehyde-carbohydrazide (GACH) was proposed for specimen preparation in scanning electron microscopy (SEM) as a means of avoiding dehydration in organic solvents, and to provide dimensionally stable biological specimens through a process of air-drying. It has been assumed that shrinkage of specimens prepared by the GACH technique should be less than that of conventionally-prepared material by critical point drying (CPD). In a previous study, Bell has reported significant shrinkage of whole cells for SEM. This report compares cell shrinkage in GACH and CPD preparations.Fibroblasts from newborn rats were grown on collagen-coated glass cover-slips (with alpha numeric grids etched onto the surface of the coverslips) in Eagle's minimum essential medium + 10% fetal calf serum for 7 d. (3). Using an inverted microscope with phase-contrast optics, micrographs were taken of the cultures in their live state and 1 h. after fixation with 2.5% glutaraldehyde in Dulbecco's phosphate buffered saline (Figs. 1 and 3).


Author(s):  
Sudeep M. Rao ◽  
Joshua Samuel ◽  
Sai S. Prakash ◽  
C. Jeffrey Brinker

Ambient pressure silica aerogel thin films have recently been prepared by exploiting reversible drying shrinkage caused by derivatization of the internal gel surface. Aerogels have porosities of upto 99.9% and due to the small size of the pores (few nanometers), large capillary stresses are produced in gels that are partially saturated with a wetting liquid. As a result of these capillary stresses, the flexible silica network undergoes strain which has been observed using environmental microscopy. This technique allows variation of the equilibrium vapor pressure and temperature, and a simultaneous monitoring of the deformation of the unconstrained film thickness. We have observed >600% deformation during the pore-filling and pore-emptying cycles. In this presentation, we discuss the unique stress-strain behavior of these films.Ref.: Sai S. Prakash, C. Jeffrey Brinker, Alan J. Hurd & Sudeep M. Rao, "Silica aerogel films prepared at ambient pressure by using surface derivatization to induce reversible drying shrinkage", Nature. Vol. 374, 30 March, 1995, 439-443.


2019 ◽  
Vol 10 (3) ◽  
pp. 2132-2138
Author(s):  
Virsa Handayani ◽  
Rezki Amriati Syarif ◽  
Ahmad Najib ◽  
Aktsar Roskiana Ahmad ◽  
Abdullah Mahmud ◽  
...  

Mahogany (Swietenia mahagoni (L.) Jacq) is one of the plants that is often used by the community as traditional medicine. One of them is antifungal, antibacterial, antidiabetic, and eczema. This study aims to obtain standardized extracts from mahogany seeds and leaves. Standardization of purified extract of mahogany has been carried out according to the monographs of extract standardization guidelines, which include testing of specific and non-specific parameters. The results of the specific parameter testing showed that the purified extract of mahogany seeds is a thick extract, brown to reddish, smells distinctive and has a bitter taste. While the purified extract of mahogany leaves is a thick extract, greenish-brown in color, distinctive smell and has a bitter taste. The chemical content of purified extract of mahogany seeds and leaves showed the presence of flavonoids, alkaloids, terpenoids and saponins. Water-soluble essence levels in mahogany seeds and leaves was 14.84% and 10.28%. While the ethanol-soluble essence levels in mahogany seeds and leaves were 15.38% and 12.43%. Testing of non-specific parameters on mahogany seeds and leaves showed the results of drying shrinkage levels of 0.22% and 8.84%, moisture content of 2.60% and 4.04%, total ash content of 1.71% and 1.93%, levels acidic insoluble ash 0.38% and 0.32%, Total Plate Number (ALT) of mahogany seed bacteria 1x102 colonies/g, Number of mahogany mold seeds 4x10 colonies/g, heavy metal lead contamination and cadmium in mahogany seeds 0.0607µg/g and<0.003µg/g. The inhibitory diameter of each concentration of seeds against Escherichia coli, 3%, 5%, 7%, and 9%, is 12,67; 13,67; 17,67; and 19,67 mm, respectively. The inhibitory diameter of each concentration of leaves against Escherichia coli, 3%, 5%, 7%, and 9%, is 10,27; 10,90; 13,46; and 15,68 mm, respectively.


2018 ◽  
Vol 56 (4) ◽  
pp. 354-354
Author(s):  
T. Hasegawa
Keyword(s):  

Author(s):  
V. N. Babakov ◽  
N. Yu. Rogovskaya ◽  
I. D. Kurdyukov ◽  
P. P. Beltyukov ◽  
S. A. Dulov ◽  
...  

The effect of aryl hydrocarbon receptor agonists (FICZ and ITE), as well as lipopolysaccharide under the toxic action of benzo(a)pyrene in HepaRG human hepatoma cells was evaluated. Active forms of the key stress-activated kinase cascades and DNA repair system proteins were used as markers of the genotoxic action of benzo(a)pyrene. A mixture of lipopolysaccharide with benzo(a)pyrene increases benzo(a)pyrene cytotoxicity and reduces the activation of DNA repair system proteins below the control level. Aryl hydrocarbon receptor agonists (FICZ and ITE) exhibit a cytoprotective effect against benzo(a) pyrene, enhance Akt1 kinase activation, and downregulate activation of the p53 protein and Chk1 and Chk2 checkpoint kinases. Thus, FICZ and ITE reduce the genotoxicity of benzo(a)pyrene.


2020 ◽  
Vol 46 (6) ◽  
pp. 875-890
Author(s):  
M. V. Monakhova ◽  
M. A. Milakina ◽  
R. M. Trikin ◽  
T. S. Oretskaya ◽  
E. A. Kubareva

Sign in / Sign up

Export Citation Format

Share Document