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Processes ◽  
2022 ◽  
Vol 10 (1) ◽  
pp. 161
Author(s):  
Wilasinee Sangsom ◽  
Chouw Inprasit

Jet impingement has been effective in reducing the process time and improvement of product quality in various industrial applications, such as textile and paper drying, electronic cooling, glass quenching and food processing. The current work applied innovative steam injection to liquid food continuous sterilization. The multiple impingement jets of steam and product came together in the impingement tank. The effects were investigated on the Reynolds number, steam temperature and jet-to-target spacing (H/d), sterilization temperature and heat transfer efficiency in water and pineapple juice tests. The Reynolds number was based on the nozzle configuration and liquid flow rate. The study investigated product injection plates formed using two, three or four circular holes (diameter 2 mm), steam injection plates with six, nine or twenty circular holes (diameter 1 mm), steam temperatures of 120, 125 or 130 °C and H/d values of 1, 3, 5 or 7. The different options were tested with water to determine the optimal conditions, and then tested with pineapple juice. The results showed that the optimal conditions from water testing that provided the highest heat transfer efficiency occurred with two jet nozzles, six steam injection plates, a steam temperature of 120 °C and an H/d value of 1.


2022 ◽  
Author(s):  
M.I Ejimofor ◽  
I.G Ezemagu ◽  
M.C Menkiti ◽  
V.I Ugonabo ◽  
B.U Ejimofor

Abstract The potential of gastropod shell conchiolin (GSC) (a waste product of the deprotenization stage of chitosan production) as one of the alternatives to chemical coagulants has been explored for treatment of paint industrial wastewater (PW). The accuracy of response surface design (RSD) and the precision of artificial intelligence (AI) in predicting and optimizing the process conditions were harnessed in raising experimental design matrix and response optimization, respectively for the bench scale jar test coagulation experiment. PW was characterized using American public health association (APHA) standard methods. Extraction of conchiolin was done via alkaline extraction method. PW contains 2098mg/l total suspended solid (TSS) above discharge limit (1905mg/l). Fourier transform infrared (FTIR) spectrum of GSC revealed a broad N–H wagging band at 750 – 650 cm−1 indicating the presence of secondary amine linked to the presence of protein. Turbidity removal from PW via one factor at a time (OFAT) was found to be a function of pH, GSC dosage, temperature and time. Artificial neural network (ANN) response prediction shows 92% correlation with the response surface design (RSD) experimental result. The optimal conditions obtained via genetic algorithm (GA) for the response optimization at the best pH of 4 indicate optimal turbidity removal of 98% at GSC dosage, time and temperature of 4 g, 20 min and 45oC, respectively.


Author(s):  
Emmanuel Ikechukwu Ugwu ◽  
Jonah Chukwuemeka Agunwamba

Corn Cob ash was used in competitive adsorption of copper, zinc, and chromium from wastewater. The central composite design; a sub-set of response surface methodology was used to optimize the adsorption of the heavy metals. The result of the statistical parameters showed the coefficient of determination (R2) of 1.000, 0.999, and 1.000 for copper, zinc, and chromium respectively. The optimal conditions obtained for adsorbent dosage, initial concentration, temperature, contact time, and particle size were 13.20 mg, 79.72 mg/l, 34.95 °C, 40.38 min, and 1400 µm, respectively with the desirability of 1.000. The predicted and the actual values of metal removal obtained were 69.41%, 76.37%, as well as 70.44%, 72.50%, 77.90 % and 71.00% for copper, zinc, and chromium respectively. The ressult indicated a good conformity between the model predicted values and the actual values, thus having small errors of 3.09%, 1.53 % and 0.56 % for copper, zinc, and chromium respectively.


2022 ◽  
Vol 12 ◽  
Author(s):  
Min Lyu ◽  
Mengke Sun ◽  
Josep Peñuelas ◽  
Jordi Sardans ◽  
Jun Sun ◽  
...  

Climate change could negatively alter plant ecosystems if rising temperatures exceed optimal conditions for obtaining carbon. The acclimation of plants to higher temperatures could mitigate this effect, but the potential of subtropical forests to acclimate still requires elucidation. We used space-for-time substitution to determine the photosynthetic and respiratory-temperature response curves, optimal temperature of photosynthesis (Topt), photosynthetic rate at Topt, temperature sensitivity (Q10), and the rate of respiration at a standard temperature of 25°C (R25) for Pinus taiwanensis at five elevations (1200, 1400, 1600, 1800, and 2000 m) in two seasons (summer and winter) in the Wuyi Mountains in China. The response of photosynthesis in P. taiwanensis leaves to temperature at the five elevations followed parabolic curves, and the response of respiration to temperature increased with temperature. Topt was higher in summer than winter at each elevation and decreased significantly with increasing elevation. Q10 decreased significantly with increasing elevation in summer but not winter. These results showed a strong thermal acclimation of foliar photosynthesis and respiration to current temperatures across elevations and seasons, and that R25 increased significantly with elevation and were higher in winter than summer at each elevation indicating that the global warming can decrease R25. These results strongly suggest that this thermal acclimation will likely occur in the coming decades under climate change, so the increase in respiration rates of P. taiwanensis in response to climatic warming may be smaller than predicted and thus may not increase atmospheric CO2 concentrations.


Molecules ◽  
2022 ◽  
Vol 27 (2) ◽  
pp. 431
Author(s):  
Roghayeh Jalili ◽  
Salimeh Chenaghlou ◽  
Alireza Khataee ◽  
Balal Khalilzadeh ◽  
Mohammad-Reza Rashidi

Human Tau protein is the most reliable biomarker for the prediction of Alzheimer’s disease (AD). However, the assay to detect low concentrations of tau protein in serum is a great challenge for the early diagnosis of AD. This paper reports an electrochemiluminescence (ECL) immunosensor for Tau protein in serum samples. Gold nanostars (AuNSs) decorated on carbon nitride nanosheets (AuNS@g-CN nanostructure) show highly strong and stable ECL activity compared to pristine CN nanosheets due to the electrocatalytic and surface plasmon effects of AuNSs. As a result of the strong electromagnetic field at branches, AuNSs showed a better ECL enhancement effect than their spherical counterpart. For the fabrication of a specific immunosensor, immobilized AuNSs were functionalized with a monoclonal antibody specific for Tau protein. In the presence of Tau protein, the ECL intensity of the immunosensor decreased considerably. Under the optimal conditions, this ECL based immunosensor exhibits a dynamic linear range from 0.1 to 100 ng mL−1 with a low limit of detection of 0.034 ng mL−1. The LOD is less than the Tau level in human serum; thus, this study provides a useful method for the determination of Tau. The fabricated ECL immunosensor was successfully applied to the detection of Tau, the biomarker in serum samples. Therefore, the present approach is very promising for application in diagnosing AD within the early stages of the disease.


2022 ◽  
Vol 6 (1) ◽  
pp. 4
Author(s):  
Nataliia Hes ◽  
Artur Mylin ◽  
Svitlana Prudius

Catalytic conversion of fructose to levulinic and formic acids over tin-containing superacid (H0 = −14.52) mixed oxide was studied. Mesoporous ZrO2–SiO2–SnO2 (Zr:Si:Sn = 1:2:0.4) was synthesized by the sol–gel method. The fructose transformation was carried out in a rotated autoclave at 160–190 °C for 1–5 h using a 20 wt.% aqueous solution. The results showed that doping ZrO2–SiO2 samples with Sn4+ ions improved both fructose conversion and selectivity toward levulinic and formic acids. Under optimal conditions of 180 °C, 3.5 h and fructose to catalyst weight ratio 20:1, levulinic and formic acids yields were 80% and 90%, respectively, at complete fructose conversion. At this, humic substances formed in the quantity of 10 wt.% based on the target products.


2022 ◽  
Vol 2022 ◽  
pp. 1-10
Author(s):  
José Pérez ◽  
Karina Gómez ◽  
Lorena Vega

Watermelon rind was used for the pectin extraction with citric acid as the extractant solvent. The effects of pH (2.0-3.0), extraction time (45-75 min), and liquid-solid ratio (10 : 1 to 40 : 1 mL/g) on the pectin yield, degree of esterification, methoxyl content, and anhydrouronic acid content were investigated using Box-Behnken surface response experimental design. The pH was the most significant variable for the pectin yield and properties. The responses optimized separately showed different optimal conditions for each one of the variables studied in this work. Therefore, the desirability function was used to determine the sole theoretical optimum for the highest pectin yield and highest anhydrouronic acid content, which was found to be pH of 2.0, extraction time of 62.31 min, and liquid-solid ratio of 35.07 mL/g. Under this optimal condition, the pectin yield, degree of esterification, methoxyl content, and anhydrouronic acid content were 24.30%, 73.30%, 10.45%, and 81.33%, respectively. At optimal conditions, watermelon rind pectin can be classified as high methoxyl and rapid-set pectin with high quality and high purity. Practical Applications. This study evaluated the pectin extraction from watermelon rind and carried out an optimization of multiple responses as a function of pH, time, and liquid-solid ratio to obtain the best preliminary quality parameters (pectin yield and anhydrouronic acid content). The results revealed that watermelon rind waste can be an inexpensive source to obtain good pectin quality and high purity. According to the chemical characterization and physicochemical properties studied, the extracted pectin from watermelon rind would have a high potential to be used in food industry.


Author(s):  
M. Nikoueifar ◽  
A. Vaheb ◽  
M. Honarpisheh

Incremental sheet forming (ISF) is an innovative forming technology which is widely used in various sectors of mechanical production. This is particularly useful for rapid prototyping and limited batch without a specific die. A new class of this method is single-point incremental forming (SPIF). This paper presents a comprehensive experimental investigation on the SPIF of Aluminum sheets, and, in particular, the influence of the forming tool is taken into account. A new rolling ball tool is designed to follow this, and the formability of the Aluminum sheets under the SPIF procedure is investigated for both new and conventional tools. Moreover, a number of important process parameters such as the feed rate, forming force, and surface roughness are considered in the experiments’ design. Finally, the optimal conditions in achieving a developed SPIF procedure in terms of the mentioned factors are reported and discussed. The findings of this work suggest that the surface quality after the forming process can be enhanced by 55% when using the new designed tool, while the forming force is reduced by 38% at the same time.


2022 ◽  
Vol 19 (2) ◽  
pp. 025202
Author(s):  
E A Vashukevich ◽  
E N Bashmakova ◽  
T Yu Golubeva ◽  
Yu M Golubev

Abstract The application of high-dimensional quantum systems (qudits) in quantum computing and communications seems to be a promising avenue due to the possibility of increasing the amount of information encoded in one physical carrier. In this work, we propose a method for implementing single-qudit gates for qudits based on light modes with orbital angular momentum (OAM). Method for logical qudits encoding, which ensures the quasi-cyclicity of operations, is introduced. Based on the protocol for converting the OAM of light in the Raman quantum memory scheme (Vashukevich et al 2020 Phys. Rev. A 101 033830), we show that the considered gates provide an extremely high level of fidelity of single-qudit transformations. We also compare quantum gates’ properties for systems of different dimensions and find the optimal conditions for carrying out transformations in the protocol under consideration.


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