Modified Anaerobic Serum Bottle Testing Procedures for Industrial Wastewaters L

1988 ◽  
Vol 23 (3) ◽  
pp. 450-459
Author(s):  
L. Cornacchio ◽  
E.R. Hall ◽  
J.T. Trevors

Abstract Serum bottle bioassay techniques are batch procedures which provide a cost efficient alternative to continuous flow studies for determining anaerobic treatability characteristics of an industrial wastewater. In addition, the toxic effect of the wastewater on the anaerobic microorganisms is easily assessed in a relatively short period of time. As part of a study to screen the anaerobic treatability characteristics of a large number of industrial wastewaters, additional research was carried out to modify the original serum bottle procedures for routine use. Several experiments were completed in which the relative proportions of inoculum, nutrient medium, and wastewater were varied. This permitted assay conditions to be optimized to prevent nutrient deficiencies and excessive lags in inoculum activity, while providing for the testing of a wide range of wastewater concentrations. The effect of changing the total assay volume on the requirement for monitoring biogas accumulation and composition was also investigated.

2020 ◽  
Vol 24 ◽  
Author(s):  
Bubun Banerjee ◽  
Gurpreet Kaur ◽  
Navdeep Kaur

: Metal-free organocatalysts are becoming an important tool for the sustainable developments of various bioactive heterocycles. On the other hand, during last two decades, calix[n]arenes have been gaining considerable attention due to their wide range of applicability in the field of supramolecular chemistry. Recently, sulfonic acid functionalized calix[n] arenes are being employed as an efficient alternative catalyst for the synthesis of various bioactive scaffolds. In this review we have summarized the catalytic efficiency of p-sulfonic acid calix[n]arenes for the synthesis of diverse biologically promising scaffolds under various reaction conditions. There is no such review available in the literature showing the catalytic applicability of p-sulfonic acid calix[n]arenes. Therefore, we strongly believe that this review will surely attract those researchers who are interested about this fascinating organocatalyst.


2021 ◽  
Vol 16 (1) ◽  
Author(s):  
Ewa Przeździecka ◽  
P. Strąk ◽  
A. Wierzbicka ◽  
A. Adhikari ◽  
A. Lysak ◽  
...  

AbstractTrends in the behavior of band gaps in short-period superlattices (SLs) composed of CdO and MgO layers were analyzed experimentally and theoretically for several thicknesses of CdO sublayers. The optical properties of the SLs were investigated by means of transmittance measurements at room temperature in the wavelength range 200–700 nm. The direct band gap of {CdO/MgO} SLs were tuned from 2.6 to 6 eV by varying the thickness of CdO from 1 to 12 monolayers while maintaining the same MgO layer thickness of 4 monolayers. Obtained values of direct and indirect band gaps are higher than those theoretically calculated by an ab initio method, but follow the same trend. X-ray measurements confirmed the presence of a rock salt structure in the SLs. Two oriented structures (111 and 100) grown on c- and r-oriented sapphire substrates were obtained. The measured lattice parameters increase with CdO layer thickness, and the experimental data are in agreement with the calculated results. This new kind of SL structure may be suitable for use in visible, UV and deep UV optoelectronics, especially because the energy gap can be precisely controlled over a wide range by modulating the sublayer thickness in the superlattices.


Author(s):  
Damian Clarke ◽  
Joseph P. Romano ◽  
Michael Wolf

When considering multiple-hypothesis tests simultaneously, standard statistical techniques will lead to overrejection of null hypotheses unless the multiplicity of the testing framework is explicitly considered. In this article, we discuss the Romano–Wolf multiple-hypothesis correction and document its implementation in Stata. The Romano–Wolf correction (asymptotically) controls the familywise error rate, that is, the probability of rejecting at least one true null hypothesis among a family of hypotheses under test. This correction is considerably more powerful than earlier multiple-testing procedures, such as the Bonferroni and Holm corrections, given that it takes into account the dependence structure of the test statistics by resampling from the original data. We describe a command, rwolf, that implements this correction and provide several examples based on a wide range of models. We document and discuss the performance gains from using rwolf over other multiple-testing procedures that control the familywise error rate.


Rusin ◽  
2021 ◽  
pp. 201-222
Author(s):  
A.I. Kudriachenko ◽  

The paper analyzes the course of events and the international context of Сarpatho- Ukrainian state’s rise and defeat in terms of role and impact of the leading European actors at the end of the 1930’s. Based on an in-depth study of the wide range of literature, documents and relevant archives, the author highlights the role of Carpatho-Ukraine, which for a short period happened to be at the epicenter of the geopolitical interests of the states whose actions or inaction fueled the warmongers. The revival and strengthening of a number of European countries at that historical period deteriorized international relations. The erosion of the Versailles-Washington bases intensified the contradictions in the foreign policy between the victorious and vanquished states. The defeated countries reinforced their positions, since the victors, who were expanding their military might at the expense of Czechoslovak Republic, including Transcarpathia, were becoming more submissive in accommodating territorial claims. This situation largely updated the approaches to the Ukrainian question. The variability of the ways to solve it largely depended on the situational decisions of the Third Reich political leadership.


1966 ◽  
Vol 23 (4) ◽  
pp. 527-538 ◽  
Author(s):  
J. R. Burt

Some properties of the enzymes amylase, phosphorylase, and phosphoglucomutase in homogenates of cod muscle have been investigated. Amylase is activated by a short period of autolysis and by chloride ions; hydrolyses cod muscle glycogen at about half the rate it hydrolyses mussel glycogen; has an optimum temperature of 52 C for up to 5 hr incubation; and has a wide range of activity with maxima around pH 5.1 and between pH. 7.0 and 7.5. Using phloridzin, an estimate of the relative importance of hydrolytic and phosphorolytic cleavage of polysaccharide in cod muscle homogenates has been made. Phosphorylase shows two activity maxima at pH 5.5 and 6.7. The properties of phosphoglucomutase, with the exception of its pH activity, in cod muscle are similar to those reported for this enzyme in other tissues. Cod muscle phosphoglucomutase has maximum activity between pH 8 and 9.


2017 ◽  
Vol 5 (5) ◽  
pp. e1320 ◽  
Author(s):  
Martin Aman ◽  
Matthias E. Sporer ◽  
Otto Riedl ◽  
Wei-Te Wang ◽  
Anne Kramer ◽  
...  

2021 ◽  
Author(s):  
Nima Safaei ◽  
Omar Smadi ◽  
Babak Safaei ◽  
Arezoo Masoud

<p>Cracks considerably reduce the life span of pavement surfaces. Currently, there is a need for the development of robust automated distress evaluation systems that comprise a low-cost crack detection method for performing fast and cost-effective roadway health monitoring practices. Most of the current methods are costly and have labor-intensive learning processes, so they are not suitable for small local-level projects with limited resources or are only usable for specific pavement types.</p> <p>This paper proposes a new method that uses an improved version of the weighted neighborhood pixels segmentation algorithm to detect cracks in 2-D pavement images. This method uses the Gaussian cumulative density function as the adaptive threshold to overcome the drawback of fixed thresholds in noisy environments. The proposed algorithm was tested on 300 images containing a wide range of noise representative of different noise conditions. This method proved to be time and cost-efficient as it took less than 3.15 seconds per 320 × 480 pixels image for a Xeon (R) 3.70 GHz CPU processor to determine the detection results. This makes the model a perfect choice for county-level pavement maintenance projects requiring cost-effective pavement crack detection systems. The validation results were promising for the detection of low to severe-level cracks (Accuracy = 97.3%, Precision = 79.21%, Recall= 89.18% and F<sub>1</sub> score = 83.9%).</p>


1996 ◽  
Vol 39 (2) ◽  
Author(s):  
G. Asch ◽  
K. Wylegalla ◽  
M. Hellweg ◽  
D. Seidl ◽  
H. Rademacher

During the Proyecto de Investigaciòn Sismològica de la Cordillera Occidental (PISCO '94) in the Atacama desert of Northern Chile, a continuously recording broadband seismic station was installed to the NW of the currently active volcano, Lascar. For the month of April, 1994, an additional network of three, short period, three-component stations was deployed around the volcano to help discriminate its seismic signals from other local seismicity. During the deployment, the volcanic activity at Lascar appeared to be limited mainly to the emission of steam and SO2. Tremor from Lascar is a random, «rapid-fire» series of events with a wide range of amplitudes and a quasi-fractal structure. The tremor is generated by an ensemble of independent elementary sources clustered in the volcanic edifice. In the short-term, the excitation of the sources fluctuates strongly, while the long-term power spectrum is very stationary.


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