scholarly journals Identification of residual non-biodegradable organic compounds in wastewater effluent after two-stage biochemical treatment

2016 ◽  
Vol 11 (1) ◽  
pp. 396-401 ◽  
Author(s):  
Liu Xuqing ◽  
Li Yayun ◽  
Liu Chao ◽  
Zhang Li ◽  
Yuan Hao ◽  
...  
Keyword(s):  
Solid Phase ◽  
Uv Spectroscopy ◽  
Scientific Basis ◽  
Unsaturated Ketone ◽  
Biochemical Treatment ◽  
Two Stage ◽  
Microbial Product ◽  
River Region ◽  
Chishui River ◽  
Complex Polymers

AbstractThe main non-biodegradable compounds (soluble microbial product – SMP) of wastewater from the Maotai aromatic factories, located in the Chishui river region, were analyzed by UV spectroscopy, and by solid-phase extraction followed by gas chromatography coupled to mass spectrometry, after a two-stage biochemical treatment. The UV-Vis spectra revealed that the wastewater contained two double-bonds in conjugated systems (conjugated diene or α, β- unsaturated ketone, etc.) and simple non-conjugated chromophores containing n electrons from carbonyl groups or the like. The residual organic non-biodegradable substances were identified using SPE-GC/MS analysis as complex polymers containing hydroxyl, carbonyl, and carboxyl functional groups with multiple connections to either benzene rings or heterocyclic rings. As these compounds are difficult to remove by conventional biochemical treatments, our findings provide a scientific basis for the design of efficient new strategies to remove SMP from wastewater.

Detection of Hepatitis a Virus in Drinking Water by Enzyme -Immunoassay Using Ultracentrifugation for Virus Concentration

1985 ◽  
Vol 17 (10) ◽  
pp. 39-41 ◽  
Author(s):  
A. Schnattinger
Keyword(s):  
Membrane Filtration ◽  
Hepatitis A ◽  
Hepatitis A Virus ◽  
Solid Phase ◽  
Phosphate Buffer Solution ◽  
Enzyme Linked Immunosorbent Assay ◽  
Virus Concentration ◽  
Buffer Solution ◽  
Solution Ph ◽  
Two Stage

Ten litres of tapwater were seeded with 200 µl (8×108 HAV particles) of a commercial (Organon Teknika) suspension of hepatitis A virus. Following WALTER and RÜDIGER (1981), the contaminated tapwater was treated with a two-stage technique for concentration of viruses from solutions with low virus titers. The two-stage technique consists of aluminium hydroxideflocculation (200 mg/l Al2(SO4)3. 18 H2O, pH 5,4-5,6) as first stage, the second stage of a lysis of aluminium hydroxidegel with citric acid/sodium citrate-buffer (pH 4,7; 1 ml/l sample), separation of viruses from the lysate by ultracentrifugation and suspension in 1 ml phosphate buffer solution (pH 7,2). A commercial solid phase enzyme-linked immunosorbent assay (ELISA) was used for the detection of HAV. HAV was detecterl in the 10.000:1 concentrates, but not in the seeded 101 samples. Approximately 4×108 of the inoculated 8×108 HAV particles were found in the 1 ml concentrates. The efficiency of detection is about 50%, the virus concentration 5000-fold. Although the percentage loss of HAV in comparison with concentration by means of membrane filtration is similar, the ultracentrifugation method yields a larger sample/concentrate ratio, so that smaller amounts of HAV can be detected more efficiently because of the smaller end-volume.

scholarly journals Scientific approaches to problems of mixtures sintering

2005 ◽  
Vol 37 (1) ◽  
pp. 3-17 ◽  
Author(s):  
Arnold Savitskii
Keyword(s):  
Driving Forces ◽  
Solid Phase ◽  
Scientific Basis ◽  
Liquid Phase Sintering ◽  
Alloy Formation ◽  
Sintering Process ◽  
Volume Changes ◽  
Powder Body ◽  
Metal Materials ◽  
Skeleton Structure

Existing theories cannot convincingly explain relationships observed during sintering of mixtures and do not always help solve practical problems of sintering metal materials and ceramics. The main weakness of the known theories is insufficient attention to the phenomenon of alloy formation and its effect on volume changes of compacts, faulty ideas regarding driving forces for the sintering process, the mistaken mechanism of dissolution of solid phase in liquid, and the inaccurate mechanisms of growth and densification during the sintering of mixtures. Besides, obsolete theories are developed, as a rule, on the basis of a two-partial model that does not permit taking into account the skeleton structure of a powder body and the presence of interparticle pores in it. Essentially fresh concepts in the theory of mixture sintering are formulated and defined in this paper. The new approaches eliminate the drawbacks and discrepancies in the existing theories and provide the scientific basis for solid state and liquid phase sintering of mixtures.

scholarly journals Dynamics of Volatile Compounds in Triticale Bread with Sourdough: From Flour to Bread

Foods ◽  
2020 ◽  
Vol 9 (12) ◽  
pp. 1837
Author(s):  
Ruta Galoburda ◽  
Evita Straumite ◽  
Martins Sabovics ◽  
Zanda Kruma
Keyword(s):  
Acetic Acid ◽  
Volatile Compounds ◽  
Solid Phase ◽  
Nutritional Composition ◽  
Gas Chromatography Mass Spectrometry ◽  
Human Consumption ◽  
Bread Making ◽  
Two Stage ◽  
Peak Areas ◽  
Flour Blend

Triticale has been suggested for human consumption due to its valuable nutritional composition. The aim of this study was to evaluate volatile compound dynamics in the technological processes of triticale bread and triticale bread with sourdough prepared using Lactobacillus sanfranciscensis based cultures. Two types of sourdough ready-to-use sourdough and two-stage sourdough were used for bread making. Triticale bread without sourdough was used as a control. Volatile compounds from a headspace of flour blend, sourdough, as well as mixed dough, fermented dough, bread crumb and crust were extracted using solid-phase microextraction (SPME) in combination with gas chromatography/mass spectrometry. Alcohols, mainly 1-hexanol, were the main volatiles in the triticale flour blend, whereas in the headspace of sourdough samples ethyl-acetate, ethanol and acetic acid dominated. Two-stage sourdough after 30 min fermentation showed the highest sum of peak areas formed by 14 volatile compounds, resulting in substrates for further aroma development in bread. A total of 29 compounds were identified in the bread: in the crumb the dominant volatile compounds were alcohols, ketones, acids, but in the crust—alcohols, aldehydes, furans dominated. The use of two-stage sourdough provided a more diverse spectrum of volatile compounds. Such volatile compounds as ethanol, 3-methyl-1-butanol, 2-methyl-1-propanol, 2-hydroxy-2-butanone, 2-methylpropanoic acid, and acetic acid were identified in all the analysed samples in all stages of bread making.

Two-Stage Solid-Phase Transition of Cubic Ice to Hexagonal Ice: Structural Origin and Kinetics

2018 ◽  
Vol 122 (50) ◽  
pp. 29009-29016 ◽  
Author(s):  
Shu-hui Guan ◽  
Cheng Shang ◽  
Si-Da Huang ◽  
Zhi-Pan Liu
Keyword(s):  
Phase Transition ◽  
Solid Phase ◽  
Two Stage ◽  
Hexagonal Ice ◽  
Solid Phase Transition

DSC Investigations of the Phase Transitions of [M(H2O)6](NO3)2 , where M = Mn, Co, Ni, Cu and Zn

1999 ◽  
Vol 54 (10-11) ◽  
pp. 595-598
Author(s):  
E. Mikuli ◽  
A. Migdał-Mikuli ◽  
S. Wróbel ◽  
B. Grad
Keyword(s):  
Phase Transition ◽  
Phase Transitions ◽  
Solid Phase ◽  
Melting Process ◽  
Melting Points ◽  
Two Stage ◽  
Two Phase ◽  
Solid Phase Transition ◽  
Cu And Zn

The phase transitions of [M(H2O)6 ](NO3)2 , where M = Mn2+ , Co2+ , Ni2+ , Cu2+ or Zn2+ have been studied at 100 -400 K by DSC. Two phase transitions connected with a two-stage melting process have been found for these five compounds. For the compound with M = Co, besides the two melting points a solid-solid phase transition at 272 K has been found.

Solid Phase Epitaxial Regrowth of Microcrystalline Si Films on a (100) Si Substrate

1988 ◽  
Vol 100 ◽  
Author(s):  
S. Roorda ◽  
S. Saito ◽  
W. C. Sinke
Keyword(s):  
Grain Size ◽  
Solid Phase ◽  
Si Substrate ◽  
Two Stage ◽  
Annealing Behaviour ◽  
Explosive Crystallization ◽  
Epitaxial Regrowth ◽  
Amorphous Si ◽  
Si Films ◽  
Size And Structure

ABSTRACTMicrocrystalline Si, as produced by explosive crystallization of an amorphous Si layer on (100) Si, shows a two-stage annealing behaviour. Initially, solid phase epitaxial regrowth occurs very rapidly at temperatures at, or above 800°C. After a few seconds, the regrowth rate slows down to the value typical for alignment of poly-Si. Solid phase epitaxial regrowth of microcrystalline Si is suggested to be strongly dependent on grain size and structure.

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