preparation of silica gel plates

... of variation (CV) Calculations of precision are largely independent of the number of replicates, except that more replicates may give a better estimate of the population variance Validation of ... 155 A Determination of Methanol and Higher Alcohols In Wine by Gas Chromatography 157 B Preparation of Fatty Acid Methyl Esters (FAMEs), and Determination of Fatty Acid Profile of Oils by Gas Chromatography ... % moisture = wt of H O in sample 100 wt of wet sample % moisture ổ wt of wet sampleử ổ wt of dried sampleử ỗ + pan ữ - ỗ + pan ữ ố ứ ố ứ = 100 (wt of wet sample + pan ) - (wt of pan ) % ash,...

Ngày tải lên: 15/05/2015, 01:00

... Per capita consumption of cheese in the U.S.A accounted for 13.6 kg in 2003, out of which 4.2 kg consisted of Cheddar cheese (USDA 2004) Consumers have a wide variety of cheese products to choose ... quality of the milk, and the aging and maturation conditions At 6–8 months of age, Cheddar cheese develops most of its flavor, and a full Cheddar cheese flavor is generally developed after year of ripening ... for sensory evaluation of Cheddar cheese (Murray and Delahunty 2000; Drake et al 2001), and the majority of them had greater than 100 h of training regarding the evaluation of dairy products Food...

Ngày tải lên: 03/04/2013, 21:06

... the first days of incubation period and became persistent This degradation of binding sites was also in line with the increment of labile Zn concentration during the first days of incubation Consequently, ... weeks of pre-incubation period, indicating the availability and activities of microorganism in river water However, as shown in Fig 3, there was no considerable change of DOC in the mixture of DOM ... of DOM of WWTP effluents and pre-incubated river water within the first week of incubation Slight DOC reduction (14%) was observed after one month of incubation In contrast to the results of the...

Ngày tải lên: 05/09/2013, 10:15

... reported that the addition of 2.5µM of phosphorus enhanced the growth of heterotrophic bacteria in the surface water of Lake Biwa, although the enhancement effect of phosphorus addition was inhibited ... Journal of Water and Environment Technology, Vol 9, No.2, 2011 Fig - Location of Lake Biwa Fig - Trend in water quality of the northern basin of Lake Biwa Data originated ... research, we evaluated the influence of phosphorus concentration on the biodegradation of DOM and discussed the possibility of pathway (4) to happen in the northern basin of Lake Biwa MATERIALS AND METHODS...

Ngày tải lên: 05/09/2013, 10:17

... father of child is absent; number of siblings and the quality of the house they live in captured by number of rooms, household usage of electricity, usage of tap water and availability of a toilet ... ownership of durable goods are highly related with current income such as number of motor vehicles, while number of television sets or number of fridges is generally low with the exception of number of ... house) Number of motor vehicles Number of TV sets Number of telephones Number of stoves Number of fridges Includes all other variables in second stage Robust LM test for joint significance of relevant...

Ngày tải lên: 14/03/2014, 11:20

... biodegradability of terrestrial DOM, i.e., the utilisation of organic compounds by soil microorganisms quantified by the disappearance of DOM or O2 or by the evolution of CO2 Methods for the determination of ... problems of these reactors are the release of DOM into the solution and the adsorption of DOM onto the biofilms Furthermore, it seems impossible to determine the pool sizes and the residence times of ... (1994) determined the effects of N additions on the mineralisation of DOM obtained from water extracts of soil samples taken at different depths of a pasture profile In the subsoil (80 – 224...

Ngày tải lên: 15/03/2014, 23:22

... functionalities Analyses of the effects of chlorination of raw water during adsorption and UF could also establish some correlation of NOM removal and membrane permeability with alteration of the physicochemical ... discussion 3.1 Comparison of sorption behavior of NOM onto IOP and PAC Fig shows UV removal efficiencies for treatment of prefiltered Nakdong River water at various dosages of IOP and PAC The UV removal ... sorption mech- Fig Comparison of UV removal efficiency between IOP and PAC adsorbents: adsorption time, 30 589 anisms of the adsorbents The majority of active sorption sites of nonporous IOP are located...

Ngày tải lên: 16/03/2014, 00:07

... at the Department of Information Engineering of the University of Pisa From 1998 to 2001, he held the position of Associate Professor of telecommunications at the University of Modena and Reggio ... with CE ST-OFDM BEM Figure 9: BER performance of the ST-OFDM BEM algorithm without outer coding NR = and K = Eb /N0 10 12 ST-OFDM BEM, iter ST-OFDM BEM, iter Figure 10: BER performance of the ST-DFDM ... Figure 11: BER performance of the ST-OFDM BEM receiver LDPC coding, NR = 1, and K = of the ST-OFDM BEM and that of the EM algorithm derived in [54] are comparable, the use of the former should be...

Ngày tải lên: 23/06/2014, 00:20

... analysed within weeks of collection (previous tests showed that this period of time did not affect the concentration of any of the gases analysed) 2.5 Statistical analysis Analysis of variance and ... layer of residues on the soil In the other plots the development of grasses and shrubs from May onwards may have avoided the development of high concentrations of mineral soil N The annual rate of ... plantation located 10 km east of Lugo (NW Spain) at an altitude of 500 m above sea-level The understorey vegetation consisted of Rubus spp., Adenocarpus complicatus and young trees of different deciduous...

Ngày tải lên: 08/08/2014, 14:21

... growth and allocation of dry matter by analysis of shoot/root ratio (mass of top/mass of root) but use of this ratio has frequently led to incorrect interpretations because of failure to recognise ... (Ledig et al., 1970) Comparison of shoot/root ratio of plants of different sizes is therefore open to serious criticism Comparison of regression coefficients of the allometric formula has been ... differences in mass of these organs would increase with constant ontogeny [N] had a strong influence on the ratio of 1!1/! to W which was stable across a wide range of plant sizes Slopes of allometric...

Ngày tải lên: 09/08/2014, 04:20

... ISSUE OF HUMIC MATTER 1.1 Concept of Humus 1.1.1 The Early Concept of Humus 1.1.2 Concept of Humus in the Third Millennium 1.2 Concept of Humic Matter 1.3 The Issue of Artifacts 1.4 The Issue of ... preservation of soil organic matter, mobilization and immobilization of elements, and biological detoxificationis presented by underscoring the issue of degradation of the soil ecosystem The use of humic ... given of the significance of statistical modeling of humification, including the use of stability coefficients, humification indexes, and models Chapter discusses the chemical composition of humic...

Ngày tải lên: 11/08/2014, 12:21

... million tons of poultry litter each year (Tan et al., 1975) In the state of Georgia alone, the official 1975 assessment amounts to a production of 720,000 metric tons of manure at the time of removal ... Distribution of Humic Matter 31 structure of humic substances The identification of the type of aromatic nucleus of the so-calledhumic acid monomers may shed light on the viability of the proposed ... plenty of space on earth for the amount of waste produced However, with population growth and the revolutions in industry and agriculture, huge amounts of waste and a variety of new types of pollutants...

Ngày tải lên: 11/08/2014, 12:21

... other books, authors often consider that the reader should know the basic of statistics, hence offer only sparse explanations of symbols and declarations of rules or assignments of limits, and the ... discovery of aquatic humic matter that has propelled the role of carbohydrates as major contributors in the formation of humic matter The concept of aquatic humic matter, and in particular of marine ... the K value relates the rate of solubility of humic acid in NaOH and the extent of mobilization in NaF of long chain humified components However, in the opinion of the present author, this is...

Ngày tải lên: 11/08/2014, 12:21

... decomposition ofplant residues results in some of the carbon and nitrogen being lost, processes considered part of the carbon and nitrogen cycles However, some of the C and a considerable amount of the ... 10016 Chemical Composition of Humic Matter 137 in which o = the difference between numbers of and H atoms per gram atom of C, and C = number of carbon atoms The value of o = negative with substances ... mmoVg of COOH or 30 mmollg in the form of phenolic-OH or other oxy-type acidic groups Unsaturation of COOH and phenolic groups is another possibility for variation in results of determination of...

Ngày tải lên: 11/08/2014, 12:21

... H,=resonance of sample, H, = resonance of reference (standard), g, = g-value of sample, and g, = g-value of reference (DPPH has a g, = 2.0036) The ESR spectra of humic substances consist of single ... of analyzing only the hydrogen atoms, or protons, of the humic molecules The usefulness of such analysis is questioned by several scientists, because of lack of success in obtaining spectra of ... sephadex gels w different exclusion limits, Tan and McCreery (1975) note that the degree of polymerization and the sizes of the molecules isolated affect molecular weights of humic matter A summary of...

Ngày tải lên: 11/08/2014, 12:21

... concentration of amino groups in humic substances is often believed to be relatively small This is perhaps one of the reasons why the positive charges of humic substances are considered to be only of TM ... negatively charged clay surfaces The use of a limit of soil pH = 3.0 is perhaps better, instead of 4.0, since this corresponds with the start of dissociation of COOH groups as explained before Therefore, ... substance, (2) types of metals, (3)dissociation of functional groups, and (4) saturation of binding sites Metal complexes of fulvic acids are in general more soluble than those of humic acids This...

Ngày tải lên: 11/08/2014, 12:21

... a substance capable of altering the speed of reaction without appearing as part of the final product The names of enzymes all end with use and are descriptive of the type of compounds broken ... rate of reaction (8.14)versus that of reaction (8.15) is considered by the authors of importance for the overall quantum yield of photoreduction They believe that this quantum yield, in moles of ... cycle As a result of decomposition of plant residues a variety of nitrogenous compounds are released, e.g., amino acids, amines and peptides, part of which are used in the synthesis of humic matter,...

Ngày tải lên: 11/08/2014, 12:21

... 19–7% of total C and 22–6% of soil N in loose LF and recovered 31–9% of C and 14–6% of N in occluded LF fractions In a study of arable soils, Wander and Bidart (2000) found that the proportion of ... part of the LF The amount of C and N recovered in the CF (g C or N in per gram fraction of soil), typically

Ngày tải lên: 12/08/2014, 05:21

... 2,4-diacetylphloroglucinol have been implicated in suppression of take-all of wheat, Fusarium wilt of pea, cyst nematode and soft rot of potato, and Thielaviopsis root rot of tobacco (Weller et al., 2002) Antibiotic ... suppression of Pythium DO was lost as cultivation intensified (Lourd and Bouhot, 1987) Eighty-two percent of undisturbed forested soils, 67% of forest nursery soils, 53% of managed forest soils, 31% of ... chlamydospores of Fusarium spp., require an external source of energy for germination in vitro; germination of these propagules appears to be restricted because of an insufficiency of energy-yielding...

Ngày tải lên: 12/08/2014, 05:21

... is often used as an indicator of the microbial contribution to soil organic matter, plant health, and understanding nutrient fluxes (i.e., the transport and storage of nutrients) Estimates of ... important not only to take a number of samples from a site but also to note the time of sampling, to sample a number of times a year, or to repeated sampling over a number of years at the same time Sampling ... first lines of defense Other defense mechanisms include (1) the hypersensitivity response (the death of host tissue around the point of infection to stop spread), (2) lignification of the cell...

Ngày tải lên: 12/08/2014, 05:21