A note on the availability of organic nitrogen compounds in pot experiments

1925 ◽  
Vol 15 (3) ◽  
pp. 300-302 ◽  
Author(s):  
Edward M. Crowther

In the course of an investigation on the nitrification process in soils a series of pot experiments was set up to compare the manurial actions of some typical organic nitrogen compounds. The laboratory work was interrupted at an early stage; the results of the pot experiments are briefly described in this note.

2015 ◽  
Vol 6 (2) ◽  
pp. 253-274
Author(s):  
Vered Noam

The rabbinic halakhic system, with its many facets and the literary works that comprise it, reflects a new Jewish culture, almost completely distinct in its halakhic content and scope from the biblical and postbiblical culture that preceded it. By examining Jewish legislation in the area of corpse impurity as a test case, the article studies the implications of Qumranic halakhah, as a way-station between the Bible and the Mishnah, for understanding how Tannaitic halakhah developed. The impression obtained from the material reviewed in the article is that the direction of the “Tannaitic revolution” was charted, its methods set up, and its principles established, at a surprisingly early stage, before the destruction of the Second Temple, and thus at the same time that the Qumran literature was created.


1968 ◽  
Vol 34 (1) ◽  
pp. 153-158 ◽  
Author(s):  
T. A. LaRue ◽  
J. F. T. Spencer

2018 ◽  
Vol 31 ◽  
pp. 04004
Author(s):  
Gitta Agnes Putri ◽  
Sunarsih

This paper presents about the dynamic modeling of the Water Lettuce ponds as a form of improvement from the Water Hyacinth ponds. The purpose of this paper is to predict nitrogen decrease and nitrogen transformation in Water Lettuce ponds integrated with Waste Stabilization Ponds. The model consists of 4 mass balances, namely Dissolved Organic Nitrogen (DON), Particulate Organic Nitrogen (PON), ammonium (NH4+), Nitrate and Nitrite (NOx). The process of nitrogen transformation which considered in a Water Lettuce ponds, namely hydrolysis, mineralization, nitrification, denitrification, plant and bacterial uptake processes. Numerical simulations are performed by giving the values of parameters and the initial values of nitrogen compounds based on a review of previous studies. Numerical results show that the rate of change in the concentration of nitrogen compounds in the integration ponds of waste stabilization and water lettuce decreases and reaches stable at different times.


2010 ◽  
Vol 10 (6) ◽  
pp. 13969-14011 ◽  
Author(s):  
R. Holzinger ◽  
A. Kasper-Giebl ◽  
M. Staudinger ◽  
G. Schauer ◽  
T. Röckmann

Abstract. For the first time a high mass resolution thermal desorption proton transfer reaction mass spectrometer (hr-TD-PTR-MS) was deployed in the field to analyze the composition of the organic fraction of aerosols. We report on measurements from the remote Mt. Sonnblick observatory in the Austrian alps (3108 m a.s.l.) during a 7 week period in summer 2009. A total of 638 mass peaks in the range 18–392 Da were detected and quantified in aerosols. An empirical formula was tentatively attributed to 464 of these compounds by custom-made data analysis routines which consider compounds containing C, H, O, N, and S atoms. Most of the other (unidentified) compounds must contain other elements – most likely halogenated compounds. The mean total concentration of all detected compounds was 1.1 μg m−3. Oxygenated hydrocarbons constitute the bulk of the aerosol mass (75%) followed by organic nitrogen compounds (9%), inorganic compounds (mostly NH3, 8%), unidentified/halogenated (3.8%), hydrocarbons (2.7%), and organic sulfur compounds (0.8%). The measured O/C ratios are lower than expected and suggest a significant effect from charring. A significant part of the organic nitrogen compounds is non volatile. Organic carbon concentrations measured with TD-PTR-MS were about 25% lower than measurements on high volume filter samples.


2013 ◽  
Vol 62 (4) ◽  
pp. 445-452
Author(s):  
IZABELLA PISAREK ◽  
KATARZYNA GRATA

Soil microorganisms play an important role in the organic matter transformation process. The soil microorganisms also are in symbiotic relationship with plants. At the same time, soil microorganisms are sensitive to both anthropogenic and natural habitat changes. Particular characteristics of organic matter (the C:N relation, pH, the content the content of assimilated nutrients, the xenobiotics etc.) modify the biotic conditions of the soils. This particularly concerns the microorganisms which carry out the changes in the mineral and organic nitrogen compounds and the transformation of the external organic matter. The first aim of this work was to assess the influence of the sewage sediments and the manure on the phytosanitary potential of the soil environment. The second aim of this article was to estimate the number and activity of microorganisms which carry out the transformation of carbon and nitrogen compounds. This work showed the stimulating effect of the external organic matter both on the number and on the activity of most of the physiological groups. The manure mainly stimulated ammonificators, amylolitic microorganisms and Azotobacter sp. The sewage sediments mainly stimulated ammonificators, nitrifiers of I phase and cellulolytic microorganisms. The statistically significant impact of the physio-chemical soil habitat on the biological activity of the analyzed groups of microbes was also noted.


1971 ◽  
Vol 178 (1050) ◽  
pp. 111-129 ◽  

When symbiotic coelenterates, especially hermatypic corals, were incubated in the light in sea water containing NaH 14 CO 3 , small quantities of fixed 14 C were released from the tissues at a steady rate over 4 h. The rate of release was greatly increased in the presence of glycerol, glucose and alanine; the additional 14 C released was in the same substance as that added to the medium. The following related compounds had little or no effect on 14 C release : ethylene glycol, sorbose, fructose, glucosamine, glycine, proline, serine and glutamic acid. Such results have been previously reported in other symbiotic systems, and the substances causing the specific release of fixed 14 C are believed to be those which move from the autotrophic to the heterotrophic symbiont. This belief is supported here by previous observations that glycerol, glucose and alanine are among the most important organic substances released by freshly isolated zooxanthellae. Ammonium chloride increased the amount of fixed 14 C released by corals into alanine media, possibly due to conversion of ammonia to amino acids by zooxanthellae. Appreciable release of 14 C fixed in the dark also occurred into alanine solutions. These results suggest possible roles of zooxanthellae in supplying organic nitrogen compounds to the host cell at night as well as during the day. The involvement of zooxanthellae in ‘recycling’ nitrogen compounds within the association may help to explain the success of corals in seas poor in nutrients. There was substantial utilization of external glycerol and glucose when supplied at either high or low concentrations. Corals may well be able to utilize some of the small amounts of organic matter dissolved in sea water in the natural environment.


1983 ◽  
Vol 78 (3) ◽  
pp. 335-341 ◽  
Author(s):  
Frederico Simões Barbosa ◽  
Dirceu P. Pereira da Costa ◽  
Francisco Arruda

For the development of laboratory experiments on the competitive interacitons between freshwater snail populations, special snail rooms were set up in the main building of the Research Center "Aggeu Magalhães". In the current paper, the first of a series on this subject, the general methodology of the laboratory work is described in detail. Using indoor cement channels in which a uniform seminatural environment was created, interactions of freshwater snail populations can be studied with minimal interference of the usual variables. Controlled indoor environmental techniques, as described in the current paper, may also be utilized in different types of experiments in malacology, and represent a substantial technical advance in malacological work.


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