Scale-up studies for intensified production of biodiesel from used cooking oil

In this paper the effect of channel size on the transesterification of used cooking oil (UCO) with methanol using KOH as catalyst to produce biodiesel was investigated for capillaries with internal diameter ranging from 1 to 3 mm. A T-junction was used as the mixing zone of the two liquid phases. The effects of different parameters such as, internal diameter, methanol-to-oil molar ratio, reaction time, temperature, and catalyst concentration were investigated. Results showed that the conversion efficiency to biodiesel is increased by decreasing the channel size, whilst the interactions of the other variables are also discussed

GAS CHROMATOGRAPHY-MASS SPECTROSCOPIC ANALYSIS OF BLACK PLUM SEED (SYZYGIUM CUMINI) EXTRACT IN HEXANE

Objective: Black plum seed has unique medicinal value and used as antidiabetics, antibacterial, and anti-inflammatory. Methods: Gas chromatography-mass spectrometry (GC-MS) analysis of the extracts of black plum seed obtained using solvent extraction with hexane as a solvent is used to attempt the identification of prominent components. Results: Black plum seed extract is obtained by solvent extraction technique using Soxhlet extractor. A total of 10 compounds are predicted in black plum seed extract by GC-MS analysis. Conclusion: The work presented relates to the study of GC-MS analysis of the extract of black plum seed obtained using solvent extraction with hexane as a solvent. Of ten compounds of black plum seed extract, five compounds are known to have antimicrobial properties

Performance assessment of drop tube reactor for biomass fast pyrolysis using process simulator

Biomass pyrolysis process from a drop tube reactor was modelled in a plug flow reactor using Aspen Plus process simulation software. A kinetic mechanism for pyrolysis was developed considering the recent improvements and updated kinetic schemes to account for different content of cellulose, hemicellulose, and lignin. In this regard, oak, beechwood, rice straw, and cassava stalk biomasses were analyzed. The main phenomena governing the pyrolysis process are identified in terms of the characteristic times. Pyrolysis process was found to be reaction rate controlled. Effects of pyrolysis temperature on bio-oil, gases, and char yields were evaluated. At optimum pyrolysis conditions (i.e., 500?), a bio-oil yield of 67.3, 64, 43, and 52 wt.% were obtained from oak, beechwood, rice straw, and cassava stalk, respectively. Oak and beechwood were found to give high yields of bio-oil, while rice straw produced high gas and char yields compared to other biomasses. Although temperature is the main factor that plays a key role in the distribution of pyrolysis products, the composition of cellulose, hemicellulose, and lignin in the feedstock also determines the yield behaviour and composition of products. With the rise in pyrolysis temperature, further decomposition of intermediate components was initiated favouring the formation of lighter fractions. Comparably, species belonging to the aldehyde chemical family had the highest share of bio-oil components in all the investigated feedstocks. Overall, the present study shows a good agreement with the experimental study reported in the literature, confirming its validity as a predictive tool for the biomass pyrolysis process

Elucidating the Performance Limitations of Alkaline Electrolyte Membrane Electrolysis: Dominance of Anion Concentration in Membrane Electrode Assembly

Anion exchange membrane water electrolyzers (AEMWEs) offer a cost-effective technology for producing green hydrogen. Here, an AEMWE with atmospheric plasma spray non-precious metal electrodes was tested in 0.1 to 1.0 M KOH solution, correlating performance with KOH concentration systematically. The highest cell performance was achieved at 1.0 M KOH (ca. 0.4 A cm−2 at 1.80 V), which was close to a traditional alkaline electrolysis cell with ≈6.0 M KOH. The cell exhibited 0.13 V improvement in the performance in 0.30 M KOH compared with 0.10 M KOH at 0.5 A cm−2. However, this improvement becomes more limited when further increasing the KOH concentration. Electrochemical impedance and numerical simulation results show that the ohmic resistance from the membrane was the most notable limiting factor to operate in low KOH concentration and the most sensitive to the changes in KOH concentration at 0.5 A cm−2. It is suggested that the effect of activation loss is more dominant at lower current densities; however, the ohmic loss is the most limiting factor at higher current densities, which is a current range of interest for industrial applications

Association between Hepatitis B-Related Knowledge and Health-Related Quality of Life

Purpose: To evaluate the association between patient’s knowledge of Hepatitis-B and Health Related Quality of Life (HRQoL).Methods: A cross sectional, descriptive study was undertaken with 390 hepatitis-B patients attending two public hospitals in Quetta City, Pakistan. Knowledge of hepatitis-B was assessed using a prevalidated questionnaire. European Quality of Life scale was used for the assessment of HRQoL. Descriptive analysis was used to elaborate patients’ demographic characteristics while inferential statistics were applied to report the association among study variables. Spearman’s rho correlation was used to identify the association between variables.Results: Out of 390, (230, 59.5 %) were males and the mean age of the subjects was 36.2 ± 9.2 years. One hundred and three (26 %) had primary level of education and 109 (27.9 %) were employees in the private sector. Eighty four (21 %) had a monthly income of between 10001-15000 Pakistan rupees (1 PKR = 0.0115527 USD) with 272 (69.7 %) respondents resident in urban areas. Mean HRQoL and Hepatitis-B related knowledge (HBRK) scores were categorized as poor (0.37± 0.3) and (8.52 ± 2.7) respectively. The correlation coefficient between HRQoL and HBRK was -0.102 (p < 0.001), indicating a week negative association between the study variables.Conclusion: The findings indicate a negative association between Hepatitis-B related knowledge and HRQoL. Therefore, providing disease-related knowledge to patients does not necessarily improve HRQoL. More attention should be given to identify individual factors that affect HRQoL among patients with Hepatitis-B.Keywords: Health related quality of life, HRQoL, Hepatitis-B, Disease-related knowledge, Associatio

A novel technique for fast multiplication

In this paper we present the design of a new high-speed multiplication unit. The design is based on non-overlapped scanning of 3-bit ® elds of the multiplier. In this technique the partial products of the multiplicand and three bits of the multiplier are pre-calculated using only hardwired shifts. These partial products are then added using a tree of carry-save-adders, and ® nally the sum and carry vectors are added using a carry-lookahead adder. In the case of 2 s complement multiplication the tree of carry-save-adders also receives a correction output produced in parallel with the partial products. The algorithm is modelled in a hardware description language and its VLSI chip implemented. The performance of the new design is comparedwith that of other recent ones proposed in literature

Multi National Survey of the Advice Given to Muslim Kidney Graft Recipients by Muslim Nephrologists about Lifestyle and Religious Rituals with Potential Medical Risk

Muslim renal transplant recipients often ask their physicians if performing certain lifestyles or religious obligations may be harmful to their health. Permissibility as advised by an expert Muslim physician is considered as being religiously accepted. A cross-sectional, survey-based study was conducted enquiring what nephrologists would advise their transplant recipients to do, about some lifestyles and religious duties. Fifty-eight nephrologists responded to the survey. Of these, 77% routinely follow-up post-transplant patients; 34% were from Saudi Arabia, 18% from the USA, and 20% from Pakistan. Fifty-four percent of the respondents would let patients with stable graft function fast during Ramadan, while 20% would not recommend fasting at any time following transplantation. This response did not change much if the patient was diabetic although in these patients, not recommending fasting at any time increased to 32%. For kidney donors, fasting would be allowed by 58% of the respondents once the kidney function stabilizes. About 50% would let their patients perform Omrah or obligatory Hajj any time after 12 months following transplantation, and only about 3% would not recommend that at any time after transplantation. For nonobligatory Hajj, 37% and 22%, respectively, would allow. Sixty-one percent would delay the pregnancy in nullipara with stable renal function, and none of the nephrologists would deny the opportunity to pregnancy at any time. In multiparous transplant recipients, the respective frequencies would be 45% and 20%. To our knowledge, this the first study exploring the consensus among Muslim nephrologists regarding the advice they would give on performance of potentially risky lifestyles and religious rituals by Muslim posttransplant patients

Exploring hypotheses of the actions of TGF-beta 1 in epidermal wound healing using a 3D computational multiscale model of the human epidermis

In vivo and in vitro studies give a paradoxical picture of the actions of the key regulatory factor TGF-beta 1 in epidermal wound healing with it stimulating migration of keratinocytes but also inhibiting their proliferation. To try to reconcile these into an easily visualized 3D model of wound healing amenable for experimentation by cell biologists, a multiscale model of the formation of a 3D skin epithelium was established with TGF-beta 1 literature-derived rule sets and equations embedded within it. At the cellular level, an agent-based bottom-up model that focuses on individual interacting units ( keratinocytes) was used. This was based on literature-derived rules governing keratinocyte behavior and keratinocyte/ECM interactions. The selection of these rule sets is described in detail in this paper. The agent-based model was then linked with a subcellular model of TGF-beta 1 production and its action on keratinocytes simulated with a complex pathway simulator. This multiscale model can be run at a cellular level only or at a combined cellular/subcellular level. It was then initially challenged ( by wounding) to investigate the behavior of keratinocytes in wound healing at the cellular level. To investigate the possible actions of TGF-beta 1, several hypotheses were then explored by deliberately manipulating some of these rule sets at subcellular levels. This exercise readily eliminated some hypotheses and identified a sequence of spatial-temporal actions of TGF-beta 1 for normal successful wound healing in an easy-to-follow 3D model. We suggest this multiscale model offers a valuable, easy-to-visualize aid to our understanding of the actions of this key regulator in wound healing, and provides a model that can now be used to explore pathologies of wound healing