5 research outputs found
In-situ remediation of petroleumcontaminated soil by application of plantbased surfactants toward preventing environmental degradation
Remediation in this study employs the use of green plants and their extracts in
enhancing the remediation process of polluted soils. GC-MS & FTIR techniques were
employed in determining the constituents of the soil during the investigation. 60 ml of
the extracts were applied on 1 by 2 ft segments of hydrocarbon polluted site and
observed for two months. The results show that plant extract A significantly reduced the
TPHs and PAHs to 5,450 and 126.2 mg/kg, respectively, as compared to those of
extract B whose TPH and PAH values are 10,432 and 362.3 mg/kg, respectively. Both
plant extracts reduced the total petroleum hydrocarbon compounds significantly when
compared to the standard reference PAH and PAHs (4,500 mg/kg and 50 mg/kg
respectively). The microbial plate count for the three media shows that the plant based surfactant had a synergy with the identified bacteria in enhancing Phytoremediation of
the crude oil polluted site.
Novelty statement: This study examined the application of two plant-based surfactants
for remediation. These natural surfactants significantly reduced the petroleum
hydrocarbon compounds present in the soil within the in-situ observation window. These
Herbaceous plant family extracts have a great advantage as an eco-friendly alternative
to synthetic surfactants, and they also exhibited an anti-fungi characteristic. The two
biodegradable plant-based surfactants also significantly reduced the time that it could
have taken for a remediation process
Numerical Based Optimization for Natural Gas Dehydration and Glycol Regeneration
Exergy is a simultaneous measure of the quantity and quality of energy. This helps to
identify the inefficiency of the process and allows engineers to determine the cause and
magnitude of the loss for each operating unit. Natural gas dehydration via absorption
using glycol is the most economically attractive approach, and this advantage can only
stand if lower energy consuption relative to adsorption process can be obtained; thus,
timely prediction and identification of energy consumption is vital. In this study, an
energy utilization predictive model for natural gas dehydration unit energy consumption
was developed. This numeric approach will increase accuracy and reduce the high
simulation time often encountered in using other simulation software. To achieve this
novel idea, a multilayer perceptron approach which is a deep learning neural network
model built on python using Tensorflow was adopted. The model used for this study is
implemented to further increase the accuracy of the output set variables which are
matched with simulation result. Since we are dealing with a non-linear function, rectified
linear unit (ReLU) function was used to activate the neurons in hidden layers so as to
strengthen the model to be more flexible in finding relationships which are arbitrary in
the input parameter. These input parameters are fed into the steady state model and sent
to various branches of fully connected neural network models using a linear activation
function. Each branch produces a result for each output parameter thereby fitting the
model by reducing the mean squared error loss. The training data were not normalized
but left in their original form. Results showed that the adopted double hidden layer with 5
branches are uniquely branched in such a way that it predicts values for a single output
variable, which is an upgrade to the former work done with a single hidden layer in
literature. The accuracy analysis showed that the proposed double hidden layer
approach in this study out-performed the single hidden layer
Gastrointestinal Bleeding Secondary to Portal Hypertensive Duodenopathy in a Patient with Decompensated Liver Cirrhosis
With alcoholic cirrhosis and nonalcoholic fatty liver disease continuously on the rise in the United States, there is also a corresponding rise in portal hypertension. Portal hypertensive duodenopathy (PHD) is a complication of portal hypertension not commonly seen in cirrhotic patients. We present a case of a 46-year-old man who presented with decompensated liver cirrhosis secondary to gastrointestinal bleed. The patient underwent esophagogastroduodenoscopy (EGD) with findings indicative of PHD. Patient subsequently underwent transjugular intrahepatic portosystemic shunt (TIPS) with resolution of gastrointestinal bleed. We highlight TIPS as a management strategy in patients with PHD for whom less invasive measures are not effective
Liver Cholestasis Secondary to Syphilis in an Immunocompetent Patient
Liver involvement is a known feature of secondary syphilis. The prevalence of hepatitis in secondary syphilis ranges broadly from 1 to 50%. We report a case of a 37-year-old man with type 1 diabetes mellitus and sickle cell trait presenting with jaundice and acute liver cholestasis. Abdominal ultrasound revealed mild hepatic fatty infiltration. RPR and Treponema pallidum IgG results were positive with a reflex titer of 1:64. Liver biopsy revealed chronic hepatitis with normal hepatic architecture, Kupffer cell hyperplasia, hepatic cholestasis, and ductal proliferation suggestive of syphilitic hepatitis