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Natural gas is the fastest-growing fossil fuel and LNG is playing a growing role in the world’s gas supply. The liquefaction process is also by far the most energy-consuming part of the LNG chain. It is thus a priority today for the gas industry to decrease the cost and improve the efficiency of the liquefaction process of a plant. In this way, a novel techno-economic evolution of an existing NGL plant with adding an appropriate LNG production part is presented. Concerning the availability of propane, use of existing equipments and conditions of no structural changes in the existing installation, C3MR is used as the refrigeration system. For full recognition of the process, a high-accuracy surrogate model based on D-optimal approach is developed. MR composition (nitrogen, methane, ethane, and propane), inlet gas pressure of the LNG production part, demethanizer pressure, and high and low pressure of MR as the eight manipulated variables of the surrogate model predict the earned profit of the integrated plant. To increase profit, a hybrid GA-SQP optimization method is used. The results show that the earned profit of the optimized proposed plant with the LNG production capacity of 3.33 MTPA is 60.2% more than the existing NGL plant. In addition to increased earned profit, the thermodynamic efficiency is improved in the liquefaction section, too. Furthermore, the SPC value of 0.347 kWh kg−1 LNG shows that the optimized plant has acceptable liquefaction efficiency. According to the optimization results, mixture variables are more effective than process variables on the earned profit. It is noticeable that increasing the ethane recovery not always increases profit in such integrated units.

The experimental study of geopolymeric stabilized samples based on ceramic waste powder (CWP) and sodium hydroxide solution acting as an alkali activator was investigated in the present research to evaluate the possibility of geopolymeric stabilization of silty sand soil as a sustainable method for improving the mechanical properties of inshore sand soils. X-ray fluorescence spectroscopy (XRF) was employed to analyze and determine the chemical components of the CWP and natural soil. The effect of four factors on the unconfined compression strength (UCS) and failure strain (Ɛf) of silty sand soil, including CWP content (0–24%), NaOH solution concentration (0–15 M), the curing time (7, 28, and 91 days), and the initial curing temperature (25°C and 70°C), were investigated. The results demonstrated a substantial increase in both UCS and Ɛf for geopolymeric stabilized samples in comparison to natural soil and the soil that was stabilized with 5% ordinary Portland cement (OPC). The UCS and Ɛf values of the 28-day-cured optimal sample (CWP = 15% and NaOH solution concentration = 6 M) in comparison with natural soil increased from 0.080 to 2.22 MPa and from 2.31% to 5.45%, respectively. Moreover, the UCS value in this sample was 1.75, 1.81, and 1.29 times higher than the stabilized soil with 5% OPC for each curing time. Without an alkali activator, CWP addition to the soil had no effect on UCS at all curing times. However, when a 2 M NaOH solution was added to the soil without CWP, the UCS of this sample rose to 0.36 MPa after 7 days of curing. The UCS of geopolymeric stabilized samples experienced growth from 1.27 to 2.04 times by shifting the initial curing temperature from 25°C to 70°C. Through the use of energy-dispersive X-ray (EDX) spectra and scanning electron microscope (SEM) photomicrograph, the microstructure of stabilized samples was inspected. SEM photomicrographs corroborated the UCS test findings, and EDX analysis confirmed the high quality of the aluminosilicate gels' growth and production. To sum up, soil stabilization using CWP geopolymer is a cost-effective, environmentally friendly method that reduces the consumption of natural resources and energy.

Background and purpose: Recent advances in the improvement of mechanical, physical, and esthetic properties of dental composites have greatly contributed to their increasing use. However, mouthwashes with an alcohol base may adversely affect some properties of composite resins, and cause problems such as discoloration, and composite wear. Considering the increasing use of composite resins, growing demand for esthetics, and increased consumption of mouthwashes, it is imperative to assess the effect of mouthwashes on the physical properties of composite resins, such as their surface roughness. This study aimed to examine the effect of an alcohol-containing mouthwash on the surface roughness of microhybrid and nanohybrid composite resins. Materials and methods: This experimental study was conducted with the code of ethics IR.IAU.DENTAL.REC.1399.049 on 3/24/2019 at the Faculty of Dentistry, Islamic Azad University of Medical Sciences, Tehran. Sixty IPS Empress Direct (Ivoclar) nanohybrid and Vit-l-essence (Ultradent) microhybrid composite resin specimens were fabricated were fabricated with 5 mm diameter and 2 mm thickness. The specimens were immersed in distilled water at 37°C for 24 hours and were then polished with aluminum oxide abrasive discs. The specimens were then immersed in 20 mL of distilled water for 24 hours. After 24 hours, the baseline surface roughness of specimens was measured by atomic force microscopy (AFM). IPS Empress Direct and Vit-l-essence composite specimens were randomly divided into two subgroups (n=15) for immersion in 20 mL of Listerine alcohol-containing mouthwash and Listerine non-alcoholic mouthwash and incubated at 37°C for 24 hours. This protocol simulated the daily use of mouthwash for 2 minutes for a one-year duration. Their secondary surface roughness was measured by AFM. The change in surface roughness of specimens was analyzed and compared by two-way ANOVA and t-test. Results: The measurement of the initial surface roughness showed higher values in the microhybrid composite than in the nanohybrid composite. The greatest change in surface roughness occurred in the Vit-I-essence micro-hybrid composite following immersion in alcoholic mouthwash; while the smallest change occurred in the IPS Empress nanohybrid composite immersed in non-alcoholic mouthwash. Two-way ANOVA showed that the roughness difference was significant for groups immersed in alcoholic mouthwash, indicating different behavior of the two composite types following immersion in alcoholic mouthwash. The results showed that immersion of composite specimens in mouthwashes increased their surface roughness. However, the change in surface roughness of IPS Empress and Vit-I-essence composite specimens was significantly different following immersion in alcoholic mouthwash, and Vit-I-essence experienced a significantly greater change in surface roughness than IPS Empress. Conclusion: The surface roughness of both composite types increased following immersion in mouthwashes irrespective of the presence/absence of alcohol. The surface roughness of both composite types after immersion was

The theory of primordial nature (Fiṭrah) has been developed in the Islamic tradition based on Quranic, narrative, mystical, and philosophical foundations. Morteza Motahari, besides these foundations, exploits the potentials of modern sciences and philosophies and tries to propose a more comprehensive account of this theory than other Muslem thinkers. This paper, using text-oriented analytical interpretation, provides a new account of the theory of Fiṭrah based on Motahari’s perspectives, taking into accont the most imporatan objection directed to this theory and depending on Mulla Sadra’s psychology. The ontological, anthropological, epistemological, and methodological principles of this novel accont are as follows: 1. Innate (Fiṭrī) ontology is based on accepting truth, reality, the concrete world, the Origin and the Return. 2.Human beings face these realities and truths and access the with their cognitive and tendency-based dimension. 3.Human being is a unitary identity that is not separated from nature, instinct, and Fiṭrah. 4.Human being using his/her free will can move in the direction of instincts or Fiṭrī and creates an instinctive or Fiṭrī construct for him/herself. 5.According to Fiṭrah theory, both intellectual cognition and emotional tendencies represent reality. 6.According to innate epistemology, cognitive Fiṭrah and tendency-based Fiṭrah are two intertwined aspects of knowledge and have a kind of unity.7. In theory of Fiṭrah, the methods of syllogism, intuition, narration, and induction have been considered valid. 8. This theory is based on different methods that can gurantee objectivity concreteness. 9. This multifaceted method can more easily relate philosophy to sciences, so that the scientists can use philosophical theories.

Objectives: This study assessed the effect of chlorhexidine (CHX) and isopropyl alcohol (IA) on immediate and late pushout bond strength (PBS) of fiber posts to dentin. Materials and Methods: In this in vitro study, 54 single-canal premolars were endodontically treated, and randomly assigned to 3 groups (N=18) for root dentin conditioning with distilled water (control), 2% CHX, and 70% IA after post space preparation. Fiber posts were cemented with TheraCem self-adhesive cement, and each group was subdivided into two subgroups (N=9) for PBS measurement immediately after bonding, and after 5000 thermal cycles (5-55°C). The roots were then sectioned, and their PBS was measured. The mode of failure was evaluated under a stereomicroscope at ×40 magnification. Data were analyzed by repeated measures ANOVA and Tukey’s test (alpha=0.05). Results: The highest PBS was noted in the IA group (21.12 MPa) after 24 hours and the lowest PBS belonged to the control group after thermocycling (7.48 MPa). The immediate and post-thermocycling PBS were significantly lower in the control group than the CHX group (P

Abstract.--Cressa truxillensis, commonly known as alkali weed, is native to western North America and is used in revegetation projects in saline or alkaline soils at locations such as the Ballona [...]

An elderly woman with a history of myelodysplastic syndrome complicated by cavitary pneumonia treated with antibiotics and antifungal therapy was admitted with severe sepsis and pulmonary opacities on imaging. Pulmonary infection with Scedosporium prolificans, was diagnosed on bronchopulmonary lavage (BAL). This common environmental fungus is known to cause rare but severe infection in immunocompromised hosts. The patient was diagnosed with progression to acute myeloid leukemia during the hospitalization for which chemotherapy was initiated. Despite broadening antifungal therapy, the patient developed multi-organ system failure and died.