Établissement d'une méthode de caractérisation minéralogique décrivant les sols contaminés par le plomb

2003 ◽  
Vol 40 (4) ◽  
pp. 731-741 ◽  
Author(s):  
Josée Duchesne ◽  
Guy Mercier
Keyword(s):  
Contaminated Soils ◽  
Metal Contamination ◽  
Trial And Error ◽  
Mineralogical Characterization ◽  
Industrial Sites ◽  
Average Proportion ◽  
Treatment Technologies ◽  
Few Data ◽  
Extraction Of Metals ◽  
Selection Of

Many metal-contaminated soils originate in old abandoned industrial sites. One of the problems encountered in the reclamation of soils lies in the selection of the decontamination techniques. Few data are available to predict the efficiency of the extraction of metals from the contaminated soils. Moreover, a signifiant part of the contamination is often found as particles. These can be extracted from the soils by means of mineralurgical separation techniques. A trial and error procedure is often used for selecting the technique and the procedure parameters. The purpose of this study is to develop a method of mineralogical characterization for the identification and localisation of the metal contamination so as to allow a more enlightened choice of the mineralurgical treatments. Besides the identification of the contaminant particles, the method takes into account the distribution of contaminants, which can be found on the surface of the particles or included within the volume of the particle, the average proportion and the size of the contaminants in the contaminated particles, and the association of the iron oxide contaminant. The frequency of appearance of the particles depending on the different categories of the method guides the choice of the treatment technologies to be used so as to optimize the extraction of contaminant particles.Key words: metals, contamination, soils, lead, mineralurgical techniques, mineralogy.[Journal translation]

The Sizer-Dissector for Aneurysm Clip Selection: Technical Note

Neurosurgery ◽  
2002 ◽  
Vol 50 (3) ◽  
pp. 669-671 ◽  
Author(s):  
Steven L. Giannotta
Keyword(s):  
Technical Note ◽  
Trial And Error ◽  
Aneurysm Clip ◽  
Blade Length ◽  
Permanent Occlusion ◽  
The Wire ◽  
Selection Of

Abstract OBJECTIVE: Appropriate clip selection frequently becomes a matter of trial and error because of inadequate dissection of the pathway for each clip blade. To facilitate selection of the proper clip size, a series of dissectors have been designed that mimic the exact caliber of each category of Sugita clips. METHODS: Three lines of sizer-dissectors reflecting the wire size of the most commonly used Sugita clips were developed by attaching a single aneurysm clip blade to a rounded microdissector handle. Each sizer-dissector is scaled in millimeters and is available in straight and angled configurations. Once dissection is presumed to be complete, the device is passed through the pathway of the intended aneurysm clip blades, and the clip with the appropriate caliber and length for permanent occlusion is selected. RESULTS: During dissection and clip ligation of 83 aneurysms, the sizer-dissector was used to select the blade length in 16 lesions and the blade caliber in 5 lesions. There were no complications associated with deployment of the device. CONCLUSION: By use of the sizer-dissector before attempting clip placement, clip selection is facilitated, safety is enhanced, and clip wastage is reduced.

data a; * significance level; a=0.05; * variance of difference of two observations on the log scale; * sigmaW = within-subjects standard deviation; sigmaW=0.355; s=sqrt(2)*sigmaW; * total number of subjects (needs to be a multiple of 2); n=58; * error degrees of freedom for AB/BA cross-over with n subjects in total; n2=n-2; * ratio = mu_T/mu_R; ratio=1.00; run; data b; set a; * calculate power; t1=tinv(1-a,n-2); t2=-t1; nc1=(sqrt(n))*((log(ratio)-log(0.8))/s); nc2=(sqrt(n))*((log(ratio)-log(1.25))/s); df=(sqrt(n-2))*((nc1-nc2)/(2*t1)); prob1=probt(t1,df,nc1); prob2=probt(t2,df,nc2); answer=prob2-prob1; power=answer*100; run; proc print data=b; run; As an example of using this SAS code, suppose µ = 1, σ = 0.355, α = 0.05 and n = 58. The power (as a percentage) is calculated as 90.4. The required number of subjects to achieve a given power can easily be obtained by trial and error using a selection of values of n. An alternative approach is to use trial and error directly on the sample size n for a given power. For more on this see Phillips (1990) and Diletti et al. (1991), for example. 7.4 Individual bioequivalence As noted in Section 7.1, individual bioequivalence (IBE) is a criterion for deciding if a patient who is currently being treated with R can be

2003 ◽  
pp. 362-362
Keyword(s):  
Standard Deviation ◽  
Sample Size ◽  
Degrees Of Freedom ◽  
Trial And Error ◽  
Significance Level ◽  
Individual Bioequivalence ◽  
Alternative Approach ◽  
Within Subjects ◽  
Log Ratio ◽  
Selection Of

scholarly journals Heavy Metals Concentration in Contaminated Soils from Southern Part of Romania

2011 ◽  
Vol 68 (2) ◽  
Author(s):  
Diana FLORESCU ◽  
Andreea IORDACHE ◽  
Claudia SANDRU ◽  
Elena HORJ ◽  
Roxana IONETE ◽  
...  
Keyword(s):  
Heavy Metals ◽  
Heavy Metal ◽  
Contaminated Soils ◽  
Metal Contamination ◽  
Industrial Waste ◽  
Heavy Metal Contamination ◽  
Land Application ◽  
Industrial Wastes ◽  
Treatment Processes ◽  
Contamination Of Soils

As a result of accidental spills or leaks, industrial wastes may enter in soil and in streams. Some of the contaminants may not be completely removed by treatment processes; therefore, they could become a problem for these sources. The use of synthetic products (e.g. pesticides, paints, batteries, industrial waste, and land application of industrial or domestic sludge) can result in heavy metal contamination of soils.

scholarly journals Potential risks of antibiotic resistant bacteria and genes in bioremediation of petroleum hydrocarbon contaminated soils

2020 ◽  
Vol 22 (5) ◽  
pp. 1110-1124 ◽  
Author(s):  
Colin J. Cunningham ◽  
Maria S. Kuyukina ◽  
Irena B. Ivshina ◽  
Alexandr I. Konev ◽  
Tatyana A. Peshkur ◽  
...  
Keyword(s):  
Antibiotic Resistance ◽  
Contaminated Soil ◽  
Contaminated Soils ◽  
Petroleum Hydrocarbon ◽  
Resistant Bacteria ◽  
Careful Selection ◽  
Bacterial Strains ◽  
Antibiotic Resistant ◽  
Potential Risks ◽  
Selection Of

The problems associated with potential risks of antibiotic resistance spreading during bioremediation of oil-contaminated soil are discussed. Careful selection of bacterial strains and pretreatment of organic wastes used as fertilizers are suggested.

scholarly journals Petrographic and Chemical–Mineralogical Characterization of Mortars from the Cistern at Amaiur Castle (Navarre, Spain)

Minerals ◽  
2020 ◽  
Vol 10 (4) ◽  
pp. 311 ◽  
Author(s):  
Graciela Ponce-Antón ◽  
Maria Cruz Zuluaga ◽  
Luis Angel Ortega ◽  
Juantxo Agirre Mauleon
Keyword(s):  
Organic Additive ◽  
X Ray Diffraction ◽  
Mineralogical Characterization ◽  
X Ray ◽  
Rock Fragments ◽  
Application Techniques ◽  
Aggregate Nature ◽  
Specific Construction ◽  
Selection Of

Mortars from the cistern in Amaiur Castle (Navarre, Spain) were analysed to assess the mortar manufacturing process and application techniques. To this end, optical microscopy, scanning electron microscopy (SEM), thermogravimetric analysis, X-ray fluorescence (XRF), X-ray diffraction (XRD), Raman microspectroscopy, and Fourier transform infrared spectroscopy (FTIR) were performed. The study of both structural and plaster mortars from Amaiur Castle cistern show patterns/rules in the mortar manufacture according to the specific construction requirements. A multilayer application technique was used for the construction of the cistern tank. Deliberate selection of the aggregate nature and grading contributed to mortar impermeability. Ceramic and silico-aluminous rock fragments were used as aggregates in the cistern tank to confer hydraulicity to the mortars, instead of carbonated aggregates as used in the vault. Aluminosilicated phases present in the aggregates led to the formation of amesite, which is a magnesium aluminosilicate hydrate (M-A-S-H) phase conferring hydraulicity to the mortar. Two types of additives were identified in the outer pigmented layer of plaster. Beeswax was the identified organic additive used to improve the impermeability of mortar, while hematite was the identified inorganic additive giving rise to the reddish colour of the layer.

scholarly journals Chemical Characterization of Capsule-Brewed Espresso Coffee Aroma from the Most Widespread Italian Brands by HS-SPME/GC-MS

Molecules ◽  
2020 ◽  
Vol 25 (5) ◽  
pp. 1166
Author(s):  
Veronica Lolli ◽  
Animesh Acharjee ◽  
Donato Angelino ◽  
Michele Tassotti ◽  
Daniele Del Rio ◽  
...  
Keyword(s):  
Solid Phase Microextraction ◽  
Solid Phase ◽  
Chemical Characterization ◽  
Gas Chromatography Mass Spectrometry ◽  
Multivariate Statistical ◽  
Espresso Coffee ◽  
Volatile Profiles ◽  
Few Data ◽  
Selection Of

Coffee capsules market is on the rise as it allows access to a wide selection of coffee, differing in taste and brand. However, few data about the chemical characterization of the capsule-brewed coffee aroma are available. In this work, an untargeted approach using headspace solid-phase microextraction (HS-SPME) coupled to gas chromatography–mass spectrometry (GC-MS) and combined to chemometrics was performed to study and compare aroma profile from 65 capsule-brewed espresso coffees (ECs) commercialized by five of the most representative brands in Italy. Volatile profiles obtained from ECs were subjected to multivariate statistical analysis, which generally did not show a significant variability among coffees belonging to the same brand, except for those modified after the addition of specific flavor additives or aromatic substances (such as caramel, chocolate, etc.). Similarities may be related to the starting coffee brew or the processing method, which is likely the same for each individual brand. Additionally, partial least squares discriminant analysis (PLS-DA) showed that capsules from a specific brand contain the highest concentration of pyrazines, thus characterized by an intense and characteristic aroma, and a stronger note than those from the other brands. This study supports that the chemical analysis in conjunction with chemometric tools is a useful approach for assessing flavor quality, even if the need remains to identify volatile markers of high-quality beverages.

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