Chalcones (1,3-diaryl-2-propen-1-ones) and their heterocyclic analogues, belong to the flavonoid family, which possess a number of interesting biological properties such as antioxidant, cytotoxic, ...anticancer, antimicrobial, antiprotozoal, antiulcer, antihistaminic and anti-inflammatory activities. Several pure chalcones have been approved for clinical use or tested in humans. Clinical trials have shown that these compounds reached reasonable plasma concentration and are well-tolerated. For this reason they are an object of continuously growing interest amongst the scientists. However, much of the pharmacological potential of chalcones is still not utilized. The purpose of this review is to provide an overview of the pharmacological activity of naturally occurring and synthetic chalcones. This review highlights more recent pharmacological screening of these compounds, their mechanisms of action and relevant structure-activity relationships.
The low-cost activated carbon was prepared from
Tamarind wood an agricultural waste material, by chemical activation with zinc chloride. Activated carbon adsorption is an effective means for reducing ...organic chemicals, chlorine, heavy metals and unpleasant tastes and odours in effluent or colored substances from gas or liquid streams. Central composite design (CCD) was applied to study the influence of activation temperature, chemical ratio of zinc chloride to
Tamarind wood and activation time on the chemical activation process of
Tamarind wood. Two quadratic models were developed for yield of activated carbon and adsorption of malachite green oxalate using Design-Expert software. The models were used to calculate the optimum operating conditions for production of activated carbon providing a compromise between yield and adsorption of the process. The yield (45.26
wt.%) and adsorption (99.9%) of the activated carbon produced at these operating conditions showed an excellent agreement with the amounts predicted by the models.
The present paper discusses response surface methodology (RSM) as an efficient approach for predictive model building and optimization of chromium adsorption on developed activated carbon. In this ...work the application of RSM is presented for optimizing the removal of Cr(VI) ions from aqua solutions using activated carbon as adsorbent. All experiments were performed according to statistical designs in order to develop the predictive regression models used for optimization. The optimization of adsorption of chromium on activated carbon was carried out to ensure a high adsorption efficiency at low adsorbent dose and high initial concentration of Cr(VI). While the goal of adsorption of chromium optimization was to improve adsorption conditions in batch process, i.e., to minimize the adsorbent dose and to increase the initial concentration of Cr(VI). In the adsorption experiments a laboratory developed Tamarind wood activated carbon made of chemical activation (zinc chloride) was used. A 2
4 full factorial central composite design experimental design was employed. Analysis of variance (ANOVA) showed a high coefficient of determination value (
R
2
=
0.928) and satisfactory prediction second-order regression model was derived. Maximum chromium removal efficiency was predicted and experimentally validated. The optimum adsorbent dose, temperature, initial concentration of Cr(VI) and initial pH of the Cr(VI) solution were found to be 4.3
g/l, 32
°C, 20.15
mg/l and 5.41 respectively. Under optimal value of process parameters, high removal (>89%) was obtained for Cr(VI).
Agriculture residues such as palm shell are one of the biomass categories that can be utilized for conversion to bio-oil by using pyrolysis process. Palm shells were pyrolyzed in a fluidized-bed ...reactor at 400, 500, 600, 700 and 800 °C with N
2 as carrier gas at flow rate 1, 2, 3, 4 and 5 L/min. The objective of the present work is to determine the effects of temperature, flow rate of N
2, particle size and reaction time on the optimization of production of renewable bio-oil from palm shell. According to this study the maximum yield of bio-oil (47.3 wt%) can be obtained, working at the medium level for the operation temperature (500 °C) and 2 L/min of N
2 flow rate at 60 min reaction time. Temperature is the most important factor, having a significant positive effect on yield product of bio-oil. The oil was characterized by Fourier Transform infra-red (FT-IR) spectroscopy and gas chromatography/mass spectrometry (GC–MS) techniques.
► This study reports the results of experimental investing of conversion palm shell into bio-oil by using pyrolysis and to find the optimum condition to produce the highest yield of bio-oil. ► Several parameters which have effect to the process such as temperature, N
2 flow rate, reaction time and particle size is will be investigated in this study. ► The outcome of this result will be important for abatement and control of increasingly waste palm shell storage problems any energy source to the world.
•About 14.72% of the total landmass in Malaysia was used for oil palm plantations.•Oil palm tree residues were pyrolyzed to produce bio-oil and bio-char.•The process was performed at a temperature of ...500°C and reaction time of 60min.•Characterization of the products was performed.
Oil palm tree residues are a rich biomass resource in Malaysia, and it is therefore very important that they be utilized for more beneficial purposes, particularly in the context of the development of biofuels. This paper described the possibility of utilizing oil palm tree residues as biofuels by producing bio-oil and bio-char via pyrolysis. The process was performed in a fixed-bed reactor at a temperature of 500°C, a nitrogen flow rate of 2L/min and a reaction time of 60min. The physical and chemical properties of the products, which are important for biofuel testing, were then characterized. The results showed that the yields of the bio-oil and bio-char obtained from different residues varied within the ranges of 16.58–43.50wt% and 28.63–36.75wt%, respectively. The variations in the yields resulted from differences in the relative amounts of cellulose, hemicellulose, lignin, volatiles, fixed carbon, and ash in the samples. The energy density of the bio-char was found to be higher than that of the bio-oil. The highest energy density of the bio-char was obtained from a palm leaf sample (23.32MJ/kg), while that of the bio-oil was obtained from a frond sample (15.41MJ/kg).
Enhanced Recovery After Surgery (ERAS) is a multimodal perioperative care bundle aimed at the early recovery of patients. Well accepted in gastric and pelvic surgeries, there is minimal evidence in ...neurosurgery and neurocritical care barring spinal surgeries. We wished to compare the length of intensive care unit (ICU) or high dependency unit (HDU) stay of patients undergoing elective craniotomy for supratentorial neurosurgery: ERAS protocol versus routine care. The secondary objective was to compare the postoperative pain scores, opioid use, glycemic control, and the duration of postoperative hospital stay between the two groups.
In this pragmatic non-randomized controlled trial (CTRI/2017/07/015451), consenting adult patients scheduled for elective supratentorial intracranial tumor excision were enrolled prospectively after institutional ethical clearance and consent. Elements-of-care in the ERAS group were- Preoperative -family education, complex-carbohydrate drink, flupiritine; Intraoperative - scalp blocks, limited opioids, rigorous fluid and temperature regulation; Postoperative- flupiritine, early mobilization, removal of catheters, and initiation of feeds. Apart from these, all perioperative protocols and management strategies were similar between groups. The two groups were compared with regards to the length of ICU stay, pain scores in ICU, opioid requirement, glycemic control, and hospital stay duration. The decision for discharge from ICU and hospital, data collection, and analysis was by independent assessors blind to the patient group.
Seventy patients were enrolled. Baseline demographics - age, sex, tumor volume, and comorbidities were comparable between the groups. The proportion of patients staying in the ICU for less than 48 h after surgery, the cumulative insulin requirement, and the episodes of VAS scores > 4 in the first 48 h after surgery was significantly less in the ERAS group - 40.6% vs. 65.7%, 0.6 (±2.5) units vs. 3.6 (±8.1) units, and one vs. ten episodes (p = 0.04, 0.001, 0.004 respectively). The total hospital stay was similar in both groups.
The study demonstrated a significant reduction in the proportion of patients requiring ICU/ HDU stay > 48 h. Better pain and glycemic control in the postoperative period may have contributed to a decreased stay. More extensive randomized studies may be designed to confirm these results.
Clinical Trial Registry of India ( CTRI/2018/04/013247 ), registered retrospectively on April 2018.
In this work, the adsorption of lead(II) was studied on activated carbon prepared from
Tamarind wood with zinc chloride activation. Adsorption studies were conducted in the range of 10–50
mg/l ...initial lead(II) concentration and at temperature in the range of 10–50
°C. The experimental data were analyzed by the Freundlich isotherm and the Langmuir isotherm. Equilibrium data fitted well with the Langmuir model and Freundlich model with maximum adsorption capacity of 43.85
mg/g. The rates of adsorption were found to confirm to pseudo-second-order kinetics with good correlation and the overall rate of lead(II) uptake was found to be controlled by pore diffusion, film diffusion and particle diffusion, throughout the entire adsorption period. Boyd plot confirmed that external mass transfer was the rate-limiting step in the sorption process. Different thermodynamic parameters, viz., Δ
H°, Δ
S° and Δ
G° have also been evaluated and it has been found that the sorption was feasible, spontaneous and endothermic in nature. The results indicate that the
Tamarind wood activated could be used to effectively adsorb lead(II) from aqueous solutions.
In this work palm shell waste was pyrolyzed to produces bio-oil. The effects of several parameters on the pyrolysis efficiency were tested to identify the optimal bio-oil production conditions. The ...tested parameters include temperature, N
2 flow rate, feed-stock particle size, and reaction time. The experiments were conducted using a fix-bed reactor. The efficient response surface methodology (RSM), with a central composite design (CCD), were used for modeling and optimization the process parameters. The results showed that the second-order polynomial equation explains adequately the non-linear nature of the modeled response. An
R
2 value of 0.9337 indicates a sufficient adjustment of the model with the experimental data. The optimal conditions found to be at the temperature of 500 °C, N
2 flow rate of 2 L/min, particle size of 2 mm and reaction time of 60 min and yield of bio-oil was approximately obtained 46.4 wt %. In addition, Fourier Transform infra-red (FT-IR) spectroscopy and gas chromatography/mass spectrometry (GC–MS) were used to characterize the gained bio-oil under the optimum condition.
► The RSM, with a CCD, was used for modeling and optimization for bio-oil synthesis. ► The obtained model explains adequately the non-linear nature. ► An
R
2 value of 0.9337 ensures a sufficient adjustment of the model. ► It explains the importance of the experimental factors, their interactions.
An adsorbent prepared from sugarcane bagasse with chemical activation by zinc chloride was used to study its sorption potential on removing chromium(VI). In this work the application of response ...surface methodology (RSM) is presented for optimization of removal of Cr(VI) ions from aqua solutions using activated carbon as adsorbent. While the goal of adsorption of chromium optimization was to improve adsorption conditions in batch process, i.e., to minimize the adsorbent dose and to increase the initial concentration of Cr(VI). A 24 full factorial central composite design experimental design was employed. Analysis of variance (ANOVA) showed a high coefficient of determination value (R2=0.99) and satisfactory prediction second-order regression model was derived. Maximum chromium removal efficiency was predicted and experimentally validated. The optimum adsorbent dose, temperature, initial concentration of Cr(VI) and initial pH of the Cr(VI) solution were found to be 6.85g/L, 40 degree C, 77.5mg/l, and 8.58 respectively. Under optimal value of process parameters, high removal (>87%) was obtained for Cr(VI).
► The pyrolysis of palm shell mixed with polystyrene was performed. ► The maximum of pyrolytic liquid obtained was 68.3wt% at an optimum process condition. ► The polynomial model fits well to predict ...the response with high determination coefficients of R2 (0.972) and Q2 (0.610). ► The HHV and composition of the pyrolytic liquid were very close to those of conventional fuel oil.
The mixtures of palm shell and polystyrene waste were pyrolyzed to obtain a high-grade of pyrolytic liquid that potentially could be used as a fuel. Three effective parameters were chosen: temperature, feed ratio, and reaction time. The first phase of the study was a screening test to select the range point of each parameter that resulted in high production of liquid. The selected points were then used as reference data for an optimization study using response surface methodology. The maximum liquid yield of approximately 68.3% was obtained under optimum conditions, which were shown to be a temperature of 600°C, a palm shell/polystyrene ratio of 40:60, and a reaction time of 45min. The characterization results showed that the high heating value of the liquid obtained was 40.34MJ/kg with a water content of 1.9wt% and an oxygen content 4.24wt%. The liquid mainly consisted of aliphatic and aromatic hydrocarbons.
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