75. Limit Values for Substances with a Slow Effect (Conversion of Annual Mean Values into Shift Mean Values)

1999 ◽  
Author(s):  
F Bochmann ◽  
H. Blome
Keyword(s):  
Limit Values ◽  
Mean Values

scholarly journals Transfer of Risk elements in soil–bilberry system

2013 ◽  
Vol 32 (2) ◽  
Author(s):  
Margita Kuklová ◽  
Ján Kukla
Keyword(s):  
Forest Ecosystems ◽  
The Other ◽  
Transfer Coefficients ◽  
Limit Values ◽  
Mean Values ◽  
Risk Elements ◽  
Al Content ◽  
L System ◽  
Vaccinium Myrtillus L ◽  
Humus Horizons

AbstractKuklova M., Kukla J.: Transfer of risk elements in soil-bilberry system. Ekologia (Bratislava), Vol. 32, No. 2, p. 211-219, 2013.Transfer of Al, Cr and Ni in the soil-plant (Vaccinium myrtillus L.) system was examined in four forest ecosystems in the localities Muraň (skeli-humic podzols) and Hliniky (dystric cambisols) in the protected zone of the NP Slovensky raj. In case of Al, the transfer coefficients were low, exceeding 1 only in the litter horizon on the damaged plot in the locality Muraň. The Al content in soils was the highest at a depth of 60-70 cm (10 249 mg kg-1) on the undamaged plot in Hliniky. The amounts of Al accumulated in bilberries were higher than the background value in plants, and they made 11-22% of the maximum Al contents detected in Ooh horizons of the studied soils. Cr on the damaged plot in the locality Muraň displayed higher transfer coefficients (range 1.09-11.3) in comparison with the other plots (0.03-0.59). Considering the value representing the maximum Cr amount detected in Ooh horizon in the corresponding locality as 100%, the content of Cr in bilberries growing on the damaged plot in Muraň was 109%, in contrast to 2% on the damaged plot in Hliniky. The concentrations of Ni in soils exceeded limit values in the surface humus horizons on all studied plots. Ni displayed higher transfer coefficients, exceeding 1 only on the damaged plot in the locality Muraň. Bilberries had accumulated 6-28% Ni in the locality Muraň, and 2-6% in the locality Hliniky of the maximum amounts detected in Ooh horizons of soils. The differences in mean values of transfer coefficients for Al, Ni and Cr were statistically significant (p < 0.05).

Upgrading of the Treatment Plants in Stockholm to Meet More Stringent Requirements

1990 ◽  
Vol 22 (7-8) ◽  
pp. 77-84
Author(s):  
J. Hultgren ◽  
L.-G. Reinius ◽  
M. Tendaj
Keyword(s):  
Nitrogen Removal ◽  
Sewage Treatment ◽  
Sewage Treatment Plant ◽  
Treatment Plant ◽  
Design Flow ◽  
Limit Values ◽  
Mean Values ◽  
Reject Water ◽  
Low Phosphorus ◽  
Anoxic Zones

The purification requirements for the Stockholm sewage treatment plants will become more stringent in the future. The expected limit values for the effluent, expressed as annual mean values, are for BOD7, Tot-P, and Tot-N, 10, 0.3 and 15 mg/l respectively. If these contents are multiplied by the design flow values for the three plants, we obtain the maximum quantities which may be released. If the relevant authorities permit the municipality to distribute these total quantities as desired between the three plants, future necessary extensions can be optimized. The following main principles apply to an extension of the three plants: Loudden sewage treatment plant: This comparatively small treatment plant could, if the requirements are lower than in the other two plants, continue in operation with no other extensions than the inclusion of anoxic zones. It would, however, be necessary to refurbish the plant after a number of years of neglected maintenance. Bromma sewage treatment plant: The biological stage was extended during the 1982-84 period. For this reason, the municipality suggests that no further extensions of the aeration tanks be required, before 1995 at the earliest. A nitrogen removal with outgoing contents of Tot-N of 15-17 mg/l is expected to be achieved by measures taken to reduce the load on the biological stage instead. These measures consist of centrifuging the excess sludge and pumping it directly to the digesters instead of returning it to the inlet. Furthermore, separate treatment of the reject water from the sludge centrifuges is planned. A third measure could be changing over to a more efficient precipitation chemical to permit a further reduction of the load on the biological stage with regard to, inter alia, BOD7, Tot-N etc. To meet the requirements for phosphorus removal (0.3 mg/l), the plant will be extended with a filter stage after the existing biological stage. Henriksdal sewage treatment plant: At this plant, which is the largest of the three, the largest extensions are planned. To meet the requirements for nitrogen removal, the present volumes in the aeration tanks will be tripled and will be utilized as anoxic and aerated zones as required. Three new lines with aeration tanks and secondary sedimentation tanks will be constructed. The existing aeration tanks will also be deepened from 5 to 12 m. The requirements for low phosphorus contents in the effluent will be met by installing a filter stage, as in the Bromma plant.

scholarly journals Monte Carlo simulation of climate-weather change process at maritime ferry operating area

2017 ◽  
Vol 1 (21) ◽  
pp. 5-17
Author(s):  
Ewa Kuligowska
Keyword(s):  
Monte Carlo ◽  
Change Process ◽  
Fixed Time ◽  
Limit Values ◽  
Mean Values ◽  
Sojourn Times ◽  
Process Characteristics ◽  
The Monte Carlo Method ◽  
The Mean ◽  
Weather Change

The paper presents a computer simulation technique applied to generating the climate-weather change process at Baltic Sea restricted waters and its characteristics evaluation. The Monte Carlo method is used under the assumption of semi-Markov model of this process. A procedure and an algorithm of climate-weather change process’ realizations generating and its characteristics evaluation are proposed to be applied in C# program preparation. Using this program, the climate-weather change process’ characteristics are predicted for the maritime ferry operating area. Namely, the mean values and standard deviations of the unconditional sojourn times, the limit values of transient probabilities and the mean values of total sojourn times for the fixed time at the climate-weather states are determined.

Control of dangerous substances in discharges and microbiological abatement: European framework and a case study of an ozone disinfection system

2013 ◽  
Vol 67 (6) ◽  
pp. 1238-1246 ◽  
Author(s):  
M. Ostoich ◽  
F. Serena ◽  
L. Falletti ◽  
A. Fantoni
Keyword(s):  
Environmental Control ◽  
Limit Of Detection ◽  
Treatment Plant ◽  
Liquid Waste ◽  
Analytical Techniques ◽  
Medium Size ◽  
Limit Values ◽  
Mean Values ◽  
Dangerous Substances

Directive 2000/60/EC requires the achievement of a ‘good chemical status’ for surface water within pre-established dates. Disinfection is needed to achieve compulsory final microbial limit values (in Italy for wastewater discharges the parameter Escherichia coli – EC – is imposed by law with a maximum limit value of 5,000 cfu/100 mL). Liquid waste and disinfection by-products must be considered when designing appropriate monitoring of dangerous substances; the specific classes of substances must be investigated according to the typology of received wastewaters and liquid wastes (where applicable) and specific analytical techniques, with Limit of Detection (LOD) lower than the limit values, must be applied; the difficulties faced by national and regional environmental control Agencies is that these techniques have to be applied during ordinary activity and not only for research purposes. The study aims to present the control of dangerous substances, as a screening view, in wastewater treatment plant (WWTP) discharges in the province of Venice (Northern Italy) for the period 2007–2010 based on available data from institutional controls. In addition, the wastewater disinfection process with ozone applied to a medium size WWTP (45,000 Population Equivalents) is presented as a case study, with a view to assessing the microbiological abatement efficacy and the presence of dangerous substances. Discharge quality of the WWTPs in the province of Venice presented mean values that were higher than the LOD, but only for certain metals. For the Paese plant, zinc and chloroform were the only micro-pollutants detected with a higher level than the LOD. From microbiological data in the period 2006–2011 the disinfection abatement efficiency for Paese was, in most cases above 99% for EC, faecal coliform (FC), faecal streptococci (FS) while efficiency was slightly lower for total coliform (TC); however, the proposed criterion aimed at respecting 99.99% abatement was not completely satisfied. Therefore, despite the high organic and industrial load of the considered plant and the need to find an alternative system for chlorine, as chlorine disinfection has been banned in the Veneto region since December 2012, ozone efficiency is not completely satisfactory and other systems such as peracetic or performic acids and UV systems must be considered.

scholarly journals O1D.3 Fumigant and chemical residue 8-hour exposures in workers handling cargo from shipping containers and export logs in new zealand

2019 ◽  
Vol 76 (Suppl 1) ◽  
pp. A9.3-A10
Author(s):  
Ruth Hinz ◽  
Andrea’t Mannetje ◽  
Bill Glass ◽  
Dave McLean ◽  
Neil Pearce ◽  
...  
Keyword(s):  
Ethylene Oxide ◽  
Methyl Bromide ◽  
Geometric Mean ◽  
Exposure Limits ◽  
Limit Values ◽  
Mean Values ◽  
Personal Exposures ◽  
Shipping Containers ◽  
Standard Set ◽  
Working Day

BackgroundPrevious studies found elevated concentrations of fumigants and other chemicals in the air of unopened shipping containers, which led to the assumption that workers were likely to be highly exposed. This study assessed personal 8 hour exposures in workers handling cargo from shipping containers or export logs, which were fumigated prior to loading.Methods193 personal 8 hour air samples were collected and analysed for 1,2-dibromoethane, chloropicrin, ethylene oxide, hydrogen cyanide, hydrogen phosphide and methyl bromide, 1,2-dichloroethane, C2-alkylbenzenes, acetaldehyde, ammonia, benzene, formaldehyde, methanol, styrene and toluene. Additive Mixture Values were calculated using the Work Exposure (WES) standard set by Worksafe NZ and the Threshold Limit Values (TLV) set by the ACGIH. Linear regression was conducted to assess associations between time spent inside shipping containers and exposure (n=98).ResultsChemical exposures as indicated by median and geometric mean values were low (e.g. 2.5 and 4.4 ppb respectively for methyl bromide) and none exceeded the NZ WES, although formaldehyde exceeded the TLV in 48 (26.2%) samples. The AMV-TLV threshold of 1 was exceeded in 54 (29.5%) samples. Major differences between the occupational groups (container, log and retail workers and fumigators) were not found. Time spent inside the container was significantly and positively associated with ethylene oxide, C2-alkylbenzenes and acetaldehyde, but this was based on a small number of detectable observations (non-detects 52.0%–95.9%) and for one chemical (methyl bromide, n=94) we found inverse associations.ConclusionThis study has shown that personal exposures measured over an 8 hour working day were low, with the exception of formaldehyde, and do not confirm earlier suggestions (based on measurements inside closed containers) that they regularly exceed exposure limits. Association with time spent unloading containers was weak suggesting that exposures may result from short peak exposures rather than continuous low level exposure.

Articulatory Behavior Pre and Post Full-Mouth Tooth Extraction and Alveoloplasty

1980 ◽  
Vol 23 (3) ◽  
pp. 630-645 ◽  
Author(s):  
Gerald Zimmermann ◽  
J.A. Scott Kelso ◽  
Larry Lander
Keyword(s):  
Control Subject ◽  
High Speed ◽  
Tooth Extraction ◽  
Kinematic Parameters ◽  
Experimental Conditions ◽  
Mean Values ◽  
Articulatory Movements ◽  
The Mean ◽  
Experimental Subjects ◽  
Normal Speech

High speed cinefluorography was used to track articulatory movements preceding and following full-mouth tooth extraction and alveoloplasty in two subjects. Films also were made of a control subject on two separate days. The purpose of the study was to determine the effects of dramatically altering the structural dimensions of the oral cavity on the kinematic parameters of speech. The results showed that the experimental subjects performed differently pre and postoperatively though the changes were in different directions for the two subjects. Differences in both means and variabilities of kinematic parameters were larger between days for the experimental (operated) subjects than for the control subject. The results for the Control subject also showed significant differences in the mean values of kinematic variables between days though these day-to-day differences could not account for the effects found pre- and postoperatively. The results of the kinematic analysis, particularly the finding that transition time was most stable over the experimental conditions for the operated subjects, are used to speculate about the coordination of normal speech.

Measurement Invariance Analysis of the Parental Stress Index

2019 ◽  
Vol 35 (6) ◽  
pp. 771-778 ◽  
Author(s):  
Bernhard Piskernik ◽  
Barbara Supper ◽  
Lieselotte Ahnert
Keyword(s):  
Measurement Invariance ◽  
Parental Stress ◽  
Stress Index ◽  
Factor Analyses ◽  
Confirmatory Factor Analyses ◽  
Mean Values ◽  
Confirmatory Factor ◽  
Structural Invariance ◽  
Parent Domain ◽  
Structural Levels

Abstract. While parenting research continues to compare similarities and differences in mothers’ and fathers’ behaviors based on mean values on the respective dimensions, measurement invariance as a prerequisite for these comparisons has seldom been assured. The present study thus subjected the well-known Parenting Stress Index (PSI), widely used in models of family functioning, to a rigorous measurement invariance analysis based on ( N = 214) Austrian couples with children younger than 3 years of age. We evaluated configural, metric, scalar, and uniqueness invariance on item and subscale levels, and tested for structural invariance of means and variances of the PSI parent and child domain by second-order confirmatory factor analyses. As a result, only measurement differences on the scalar levels affected the factor scores, though negligibly. On the structural levels, no differences were found on the PSI child domain across parents, but on the PSI parent domain, mothers reported more stress.

Antiheparin Activity of Human Serum and Platelet Factor 4

1973 ◽  
Vol 30 (01) ◽  
pp. 093-105 ◽  
Author(s):  
C.H.J Sear ◽  
L Poller ◽  
F.R.C Path
Keyword(s):  
Molecular Weight ◽  
Ionic Strength ◽  
Blood Serum ◽  
Whole Blood ◽  
Platelet Rich Plasma ◽  
Gel Filtration ◽  
Normal Serum ◽  
Platelet Factor ◽  
Mean Values ◽  
Antiheparin Activity

SummaryThe antiheparin activity of normal serum has been studied by comparing the antiheparin activities of sera obtained from normal whole blood, platelet-rich plasma and platelet-’free’ plasma with a purified platelet extract during differential isoelectric precipitation and by gel filtration chromatography.The mean values for the activity of PRP-serum and PFP-serum were 106% (S.D. 11) and 10% (S.D. 3) of untreated whole blood respectively. The activity of whole blood serum, PRP serum and whole blood serum plus platelet extract precipitated under identical physical conditions, i.e. pH 7.0, I =0.008, indicating that the activities of the three samples are probably associated with PF4. PF4 precipitated from human platelet extract at pH 4.0, but this is probably due to the difference in the two biochemical environments investigated, i.e. serum and platelet extract.The gel filtration experiments revealed striking similarities between the major antiheparin activities of serum and platelet extract. At physiological pH and ionic strength both activities were associated with high molecular weight material, but at physiological pH and elevated ionic strength both activities behaved as much smaller entities of molecular weight between 25,000 and 30,000 daltons and it seems very likely that both activities are associated with the same molecule, i.e. PF4.

Comparative Study of Intranasal, Subcutaneous and Intravenous Administration of Desamino-D-Arginine Vasopressin (DDAVP)

1986 ◽  
Vol 55 (01) ◽  
pp. 108-111 ◽  
Author(s):  
M Köhler ◽  
P Hellstern ◽  
C Miyashita ◽  
G von Blohn ◽  
E Wenzel
Keyword(s):  
Factor Viii ◽  
Von Willebrand Factor ◽  
Factor Xii ◽  
Additional Advantage ◽  
Mean Values ◽  
Routes Of Administration ◽  
The Mean ◽  
Von Willebrand ◽  
Willebrand Factor ◽  
Factor Antigen

SummaryThis study was performed to evaluate the influence of different routes of administration on the efficacy of DDAVP treatment. Ten healthy volunteers received DDAVP intranasally (i.n.), subcutaneously (s.c.) and intravenously (i.v.) in a randomized cross-over trial. Factor XII and high molecular weight (HMW)-kininogen levels increased only slightly after DDAVP administration. The mean increase of factor VIII: C was 3.1 (i. v.), 2.3 (s. c.), and 1.3 (i.n.) - fold over baseline. Ristocetin cofactor (von Willebrand factor antigen) increased 3.1 (2.5), 2.0 (2.3) and 1.2 (1.2) - fold over baseline mean values after i.v., s.c. and i.n. DDAVP, respectively. The half-disappearance time of factor VIII and von Willebrand factor (vWF) after DDAVP ranged from five (factor VIII: C) to eight hours (vWF). The mean increase of fibrinolytic activity was more pronounced after i.v. DDAVP. The antidiuretic effect was moderate with no apparent differences between the routes of application. This study provides further evidence that both i.v. and s.c. DDAVP administration result in an appropriate and reliable stimulation of haemostasis. An additional advantage of s. c. administration is its suitability for home treatment.

Study of the process of forming a hole for a thread at manufacturing a high nut

2020 ◽  
Vol 76 (8) ◽  
pp. 841-846
Author(s):  
I. G. Shubin ◽  
A. A. Kurkin
Keyword(s):  
Metal Flow ◽  
Nonlinear Dependence ◽  
Geometrical Parameters ◽  
Relative Height ◽  
Forming Process ◽  
Normal Height ◽  
Accuracy Class ◽  
Limit Values ◽  
Program Complex ◽  
Class B

During manufacturing nuts of increased height, a problem of obtaining correct cylindrical form of the hole for thread and overall geometrical parameters arises. To solve the problem it is necessary to know regularity of the blank forming process. Results of the study of a technological process of high hexahedral nuts forming presented. The nuts were M18 of 22 mm height, M16 of 19 mm height and M12 of normal height 10 mm according to GOST 5915–70, accuracy class B, steel grade 10 according to GOST 10702–78. The volumetric stamping was accomplished at the five-position automatic presses of АА1822 type. It was determined, that unevenness of the metal flow in the process of plastic deformation of blanks of increased height nuts was caused by different stress conditions by their sections. To simulate the mode of deformation, the program complex QForm-3D was chosen. The complex ensured to forecast with necessary accuracy the metal flow in a blank, as well as to define the deformation force and arising stress in the working instrument. The simulation showed the presence of regularity between preliminary formed buffle and deviation of dimensions and form of a blank wall after its finishing piercing, which can be expressed by a nonlinear dependence. The limit values of the relative height of the buffle С/D = 0.56–0.588 defined, exceeding which will result in rejection of the finished product. Accounting the limit values of the relative height of the buffle will enable to correct a mode of technological operations and technological instruments at stamping of high hexahedral nuts.

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