Optimum Temperature Research Articles

The effects of dynamic factors inside the bubble on sono-hydrogen yield: A numerical study

The formation of H2 by introducing ultrasonic waves to liquid has been widely recognized as a way to provide a clean, efficient, and reliable source of H2, known as Sono-Hydro-Gen. H2 comes from the chemical effects of ultrasonic waves (sonochemistry) caused by the growth and collapse of acoustic cavitation bubbles. In this work, the effects of dynamic parameters (i.e., bubble temperature, the amount of water vapor trapped inside the bubble, and collapse time) in the evolution of cavitation bubbles on H2 production are studied numerically. For an oxygen bubble, computational simulations are performed for the wide range of acoustic amplitudes (1.5–3 atm), ultrasonic frequencies (140–515 kHz), and ambient radii (0.25–20 μm), considering 22 reversible chemical reactions and 10 chemical species inside the bubble. The numerical results show that the amount of water vapor has a significant effect on the bubble collapse temperature. At low excitation amplitudes, the amount of water vapor is not enough to cause the bubble to form a strong collapse. Nevertheless, at high excitation amplitudes, the amount of water vapor is too much to reduce the bubble temperature. There exist optimal values of bubble temperature and amount of water vapor for H2 production. The optimal bubble temperatures are 5267, 4813, 4626, and 3856 K, corresponding to H2 productions of 4.21 × 10−18, 1.29 × 10−18, 2.61 × 10−19, and 8.48 × 10−20 mol, respectively, at ultrasonic frequencies of 140, 213, 355, and 515 kHz. No matter what the excitation parameters are, the optimal water vapor fraction is 0.78 ± 0.04 for H2 production. The obtained results of the present work can provide guidelines for H2 production in acoustic cavitation.

Innovative heat sink design for enhanced cooling efficiency in Dual Active Bridge (DAB) topology

Abstract After in-depth research and analysis, aiming at the heat generation mechanism and limitations of the current heat dissipation method, this paper proposes an innovative heat dissipation design scheme. By optimizing the structural design of the heat sink, the heat dissipation surface area is increased, thus achieving more efficient heat emission and maintaining the optimal operating temperature of the equipment. Experimental data show that this new heat dissipation design significantly improves the cooling efficiency, an increase of about 60%, and provides support for the performance improvement of high-power power products, which brings a reliable and efficient cooling solution for related industries.

What's the optimal temperature control strategy in patients receiving ECPR after cardiac arrest? A network meta-analysis

What's the optimal temperature control strategy in patients receiving ECPR after cardiac arrest? A network meta-analysis

Structural and magnetic properties of rapidly solidified and Bi-bonded hot compacted Mn[formula omitted]Al45C1.7Ti[formula omitted] magnets

This study examines the impact of Ti doping on the phase formation and magnetic properties of Mn-Al-C alloys. Using melt spinning, we synthesized Mn53.3−xAl45C1.7Tix alloys (x values ranging from 0 to 1.5) producing high purity ϵ-phase ribbons. The optimal annealing treatment for the formation of ferromagnetic τ-phase is 20 min at 550 °C for all compositions. However, Ti-doped samples showed the formation of β-phase due to partial phase decomposition, and TiC precipitates were present at high Ti concentrations. Upon doping, the Curie temperature was increased from 557K (Ti free sample) to 600K. To improve the coercivity, a combination of ball milling and hot compaction, introducing Bi as a metallic binder, have resulted in increased coercivity from 0.18 T to 0.33 T. Bi addition lead to formation of a grain boundary phase aiding densification. We demonstrate how modifying composition and processing can improve the magnetic properties of Mn-Al based magnets.

Assessing the potential accuracy of a small-sized goniometer with extended dynamic range based on nuclear magnetic resonance

This paper evaluates potential accuracy characteristics of a small-sized goniometer based on nuclear magnetic resonance with an extended dynamic range. This required constructing a model of goniometer errors, estimating its accuracy based on this model, and formulating practical recommendations for the design of such a device based on the accuracy assessment. To evaluate the accuracy of a nuclear goniometer, a theoretical model was built that makes it possible to determine the optimal operating parameters of the cell gas mixture, the ranges of their permissible changes, the sensitivity of the goniometer, and the dependence of its characteristics on external and internal factors. In particular, the dependence of output signal of the device on the parameters of gas mixture and optical pumping has been determined. For a goniometer with a cell volume of 8 cm3, the optimum temperature is 130 °C, and the optimum intensity of the pumping radiation is 5 mW. The dependence of output signal on the measured angle of rotation was also established, as well as the noise and error dependence of the device on the permissible values of its parameters. Based on the model built, parameters of a goniometer with a cell volume of 8 cm3 were determined; the maximum angular sensitivity of such a goniometer with complete suppression of technical noise is δφsen=1.0 arcsec. The greatest contribution to the angle measurement error is from the instability of pumping power Ip (ΔIp/Ip=0.05) – 85 %, magnetic field B0 (ΔB0/B0=10-8) – 13 %, temperature T (ΔT/T=0,1) – 2 %. The goniometer under consideration corresponds to the medium accuracy class, δφtot≥10 arcsec. It could be used in optical manufacturing for operational control, calibration, and certification of optical products. To improve the angular accuracy of the goniometer, it is necessary to increase the stability of the laser pumping intensity

Natural Inhibitors of the Polyphenol Oxidase Activity Isolated from Shredded Stored Iceberg Lettuce (Lactuca sativa L.)

Polyphenol oxidase (PPO) is the key enzyme responsible for enzymatic browning. To extend the shelf life of shredded lettuce, knowledge about biochemical PPO properties is required. The characterization of the enzyme from shredded, cold-stored lettuce was performed using pyrocatechol and the endogenous substrate (ES) (lettuce phenolics). The optimum pH and temperature for PPO activity were 5 and 50 °C, respectively. Natural infusions used as the PPO inhibitors (IC50) were ranked as follows: lovage (0.09%), marjoram (0.13%), orange peel (0.14%), oregano (0.15%), basil (0.22%), lemon peel (0.24%), parsley leaves (0.58%), and wheat bran (1.06%). Among well-recognized PPO inhibitors, kojic acid (0.00043%), ascorbic acid (0.00053%), and L-cysteine (0.00085%) were the most effective. Among the metal ions, MgCl2, FeCl2, and CaCl2 at 0.5 mM inhibited the PPO activity most effectively (by 28%, 27%, and 21%, respectively). The substrate used (pyrocatechol/ES) significantly influenced the enzyme inhibition. Using pyrocatechol, the lovage extract acted in a mixed mode (Kmi = 27.8 mM, Vmaxi = 2.03 mU), while the ES acted according to the non-competitive mode (Kmi= 0.57 mg GAE/mL, Vmax = 0.0046 U). The study confirms that natural extracts are more effective than L-cysteine when the ES is used. A pre-storage treatment with an infusion may be potentially used to improve the quality of shredded lettuce.

Suitable temperature indicator for adverse health impacts in sub-tropical cities: a case study in Hong Kong from 2010-2019.

Heat-health warning systems and services are important preventive actions for extreme heat, however, global evidence differs on which temperature indicator is more informative for heat-health outcomes. We comprehensively assessed temperature predictors on their summer associations with adverse health impacts in a high-density subtropical city. Maximum, mean, and minimum temperatures were examined on their associations with non-cancer mortality and hospital admissions in Hong Kong during summer seasons 2010-2019 using Generalized Additive Models and Distributed Lag Non-linear Models. In summary, mean and minimum temperatures were identified as strong indicators for mortality, with a relative risk(RR) and 95% confidence interval(CI) of 1.037 (1.006-1.069) and 1.055 (1.019-1.092), respectively, at 95th percentile vs. optimal temperature. Additionally, minimum temperatures captured the effects of hospital admissions, RR1.009 (95%CI: 1.000- 1.018). In stratified analyses, significant associations were found for older adults, female sex, and respiratory-related outcomes. For comparison, there was no association between maximum temperature and health outcomes. With climate change and projected increase of night-time warming, the findings from this comprehensive assessment method are useful to strengthen heat prevention strategies and enhance heat-health warning systems. Other locations could refer to this comprehensive method to evaluate their heat risk, especially in highly urbanized environments and subtropical cities.

Toward Continuous Electrochemical Synthesis of Ferrate

AbstractFerrate (Fe(VI)) is of great interest in energy storage solutions, organic synthesis, and wastewater treatment due to its decent oxidation potential and non‐toxic end‐product formation, making it a green oxidizer. The electrochemical generation of ferrate in NaOH at current densities of j ≥ 100 mA cm−2 is presented using low‐cost sacrificial iron anodes, mild steel, and spheroidal graphite cast iron (ductile iron). Under optimized reaction parameters with 40 wt.% (14 m) NaOH and a ZrO2‐based diaphragm, spheroidal graphite cast iron shows no signs of passivation in 5 h experiments even at j = 150 mA cm−2. The results are used in a novel electrolysis cell with a combined geometric anode surface area of 230 cm2, incorporated in a mini‐plant suitable for continuous synthesis. This setup produces a peak ferrate concentration of 10.1 g L−1 (84 mm) after 5 h in 1.6 L anolyte volume, resulting in a total ferrate mass of 16.2 g. Optimal electrolysis temperatures are between 35 and 50 °C. The highest current efficiency is 63.0%, and the lowest specific energy consumption is 9.2 kWh kg−1 ferrate. The presented work is an essential step toward the continuous electrochemical synthesis of ferrate using sacrificial anodes under basic conditions.

Hydrogel composition and mechanical stiffness of 3D bioprinted cell-loaded scaffolds promote cartilage regeneration

ObjectiveTo investigate the impact of different component ratios and mechanical stiffness of the gelatin-sodium alginate composite hydrogel scaffold, fabricated through 3D bioprinting, on the viability and functionality of chondrocytes.MethodsThree different concentrations of hydrogel, designated as low, medium, and high, were prepared. The rheological properties of the hydrogel were characterized to optimize printing parameters. Subsequently, the printability and shape fidelity of the cell-loaded hydrogel scaffolds were statistically evaluated, and the chondrocyte viability was observed. Dynamic mechanical analysis was conducted to measure the modulus, thereby assessing the scaffold’s stiffness. Following a 21-day culture period, RT-PCR, histological staining, and immunostaining were employed to assess chondrocyte activity, chondrosphere aggregates formation, and cartilage matrix production.ResultsBased on rheological analysis, optimal printing temperatures for each group were determined as 27.8°C, 28.5°C, and 30°C. The optimized printing parameters could ensure the molding effect of the scaffolds on the day of printing, with the actual grid area of the scaffolds was close to the theoretical grid area. And the scaffolds exhibited good cell viability (93.24% ± 0.99%, 92.04% ± 1.49%, and 88.46% ± 1.53%). After 7 days of culture, the medium and high concentration groups showed no significant change in grid area compared to the day of printing (p > 0.05), indicating good morphological fidelity. As the hydrogel’s bicomponent ratio increased, both the storage modulus and loss modulus increased, while the loss factor remained relatively constant. The highest number of chondrocytes-formed chondrosphere aggregates in the medium concentration group was observed by light microscopy. RT-PCR results indicated significantly higher expression levels of chondrogenic genes SOX9, Agg, and Col-II in the low and medium concentration groups compared to the high concentration group (p < 0.05). Histological staining results showed that the middle concentration group formed the highest number of typical cartilage lacunae.ConclusionThe aforementioned results indicate that in 3D bioprinted cell-loaded GA-SA composite hydrogel scaffolds, the scaffolds with the composition ratio (10:3) and mechanical stiffness (∼155 kPa) exhibit sustained morphological fidelity, effectively preserve the hyaline phenotype of chondrocytes, and are more conducive to cartilage regeneration.

Preparation and Formation Mechanism of β-SiC Coatings Using a SiCl4-CH4-H2-N2 System.

The mechanism of β-SiC preparation via chemical vapor deposition (CVD) of the SiCl4-CH4-H2-N2 system remains unclear. Consequently, the change of molar Gibbs free energy of the CVD β-SiC chemical reaction in the SiCl4-CH4-H2-N2 system has been studied by the Helsinki Software Corporation (HSC) Chemistry code for the first time. The role of nitrogen in the reaction was confirmed. Seven potential reaction pathways of CVD β-SiC were presented, and the thermodynamic equilibrium components of each reaction were calculated systematically. The most viable reaction pathway and corresponding optimal temperature range for CVD β-SiC were determined. In addition, a kinetic study of CVD β-SiC was conducted. The microscopic morphology and crystal structure of β-SiC coatings prepared on the graphite surface at different temperatures were charactered by scanning electron microscopy (SEM), X-ray diffraction (XRD), Raman, etc. Ultimately, through SEM, XRD, and Raman observation, uniform and dense β-SiC coatings with fine grains and high crystallinity were successfully obtained. Furthermore, large β-SiC-coated graphite trays with diameters of 230 and 465 mm were prepared by CVD using the SiCl4-CH4-H2-N2 system, and the average thickness of β-SiC was about 100.6 μm. This study provides a theoretical basis and technical recommendations for the fabrication of SiC-coated graphite trays used in metal-organic chemical vapor deposition (MOCVD) equipment.

Effects of Climate Change on Temperature Sensitivity of Vegetation Growth in Huang-Huai-Hai Plain: Spatial–Temporal Dynamics and Ecological Adaptability

This paper explores the optimal temperature change in normalized difference vegetation index (NDVI) growth in the Huang-Huai-Hai Plain under the background of climate change, aiming to better cope with the impact of global warming on vegetation growth. The temporal and spatial variation characteristics of the NDVI and temperature factors were analyzed by using the NDVI, average temperature (Tavg), maximum temperature (Tmax) and minimum temperature (Tmin) datasets from 1982 to 2020. Through the Buishand U test and sliding slope detection, 1998 was determined to be a year of abrupt climate change. Furthermore, SHAP important feature analysis, a generalized additive model, correlation analysis, and other methods were used to identify the trend in the optimum temperature of vegetation growth before and after climate change. The results showed that (1) from 1982 to 2020, Tavg, Tmax, Tmin, and the NDVI in Huang-Huai-Hai Plain showed a significant upward trend. At the same time, the spatial distribution of these indicators shows the distribution characteristics of high in the south and low in the north. (2) The NDVI was positively correlated with Tavg, Tmax, and Tmin, and the correlation with Tmin was most significant. (3) The most suitable Tavg, Tmax, and Tmin intervals for vegetation growth were 20~30 °C, 25~35 °C, and 16~25 °C, respectively. (4) The optimum temperature range of vegetation growth was expanded after climate change, and the change rates of the Tavg and Tmax lower limits reached 24% and 25%, respectively, under the best condition of vegetation growth. (5) After abrupt climate change, the temperature suitable for vegetation growth increased significantly in the northern part of the plain but decreased slightly in the southern part.

Results on the Use of an Original Burner for Reducing the Three-Way Catalyst Light-Off Time

Individual road mobility comes with two major challenges: greenhouse gas emissions related to global warming and chemical pollution. For the pollution reduction in the spark ignition engine vehicle, the standard and reliable aftertreatment technology is the three-way catalytic converter (TWC). However, the TWC starts to convert once an optimal temperature, usually known as the light-off temperature, is reached. There are many methods to reduce the warm-up period of the TWC, among which is using a burner. The initial question underlying this study was to see if the use of a relatively straightforward extra-combustion device mounted upstream the TWC, without complex elements, was able to serve the purpose of reducing the light-off time. Consequently, an original burner was designed and investigated numerically via the CFD method and experimentally via measurements of the temperature evolution within a TWC, along with the emissions specific to the burner’s operation. The main findings of this study are: (1) the CFD-based examination is a good way to decide on how to achieve the so-called fit-for-purpose internal aerodynamics of the burner (i.e., to obtain a homogeneous mixture) and (2) to reach the light-off temperature, conventionally taken as 500 K, the burner was operated for 5.2 s, i.e., 3.6 g of gasoline injected, 2.7 g of CO2 and 1.351 g of CO, respectively, emitted. Moreover, this study identified measures for improving the burner’s design as well as an enhanced procedure for the burner’s operating control both aiming to produce a cleaner combustion during the TWC pre-heating.

A novel alkali and thermotolerant protease from Aeromonas spp. retrieved from wastewater

Enzymes are integral to numerous industrial processes, with a growing global demand for various enzyme types. Protease enzymes, in particular, have proven to be cost-effective, stable, and compatible alternatives to traditional chemical processes in both industrial and environmental applications. In this study, an alkaline protease-producing strain of Aeromonas spp. was isolated from a wastewater treatment plant in Iran. The protease production was confirmed by culturing the strain on casein agar medium. The bacterium was identified through morphological, biochemical, and 16 S rRNA sequencing analyses. The optimal culture medium for bacterial growth and enzyme production was obtained using peptone, salt, yeast extract, galactose, and CaCl₂ at an initial pH of 8. Maximum protease production was achieved after 20 h of incubation at 40 °C. To partially purify the enzyme, the supernatant of the bacterial culture medium was first centrifuged, and the enzyme was precipitated using ammonium sulfate, followed by dialysis. Zymography revealed the production of one type of protease during bacterial growth. The partially purified protease exhibited optimal activity at pH 8.5 and maximum stability at pH 9. The optimum temperature for maximum enzyme activity was observed at 50 °C, with 100% residual activity retained for 1 h at 0 °C. The effect of metal ions on enzyme activity was assessed, revealing that KCl induced the most significant effects (p < 0.0001) on enzyme activity. Chemical amino acid modifiers and inhibitors, such as EDTA, DEPSI, and IAA, did not exhibit significant inhibition. In contrast, PMSF and HNBB significantly (p < 0.0001) reduced enzyme activity, suggesting that the enzyme could be classified as a serine protease. The protease also demonstrated high stability in the presence of 2% SDS, showing no signs inactivation. The alkaline pH optimum, thermal stability, and resistance to SDS exhibited by the protease produced by the Aeromonas strain are particularly promising characteristics that warrant further investigation. Based on preliminary tests and the enzyme’s characteristics, this protease can be recommended for various applications, pending further studies.

Knowledge Distillation and Student-Teacher Learning for Weed Detection in Turf

Abstract Machine vision-based herbicide applications relying on object detection or image classification deep convolutional neural network (DCNN) demand high memory and computational resources, resulting in lengthy inference times. To tackle these challenges, this study assessed the effectiveness of three teacher models, each trained on datasets of varying sizes, including D-20k (comprising 10,000 true positive and true negative images) and D-10k (comprising 5,000 true positive and true negative images). Additionally, knowledge distillation was performed on their corresponding student models across a range of temperature settings. After the process of student-teacher learning, the parameters of all student models were reduced. ResNet18 not only achieved higher accuracy (ACC≥0.989) but also maintained higher frames per second (FPS≥742.9) under its optimal temperature condition (T=1). Overall, the results suggest that employing knowledge distillation on the machine vision models enabled accurate and reliable weed detection in turf while reducing the need for extensive computational resources, thereby facilitating real-time weed detection and contributing to the development of smart, machine vision-based sprayers.

Mathematical Model for Optimum Temperature and Humidity Determination of Mashed Mushroom in Greenhouses by using Smart Farm Technology and Innovation

Background: At the present time, various technologies have been used in the development of modern agriculture. The technology used to help in the development of agricultural farms is called a smart farm. Mashed Mushroom is a food due to their usefulness and high nutritional and good income, as this result, the researcher was interested in the use of technology and innovation of smart farms in the mashed mushroom cultivation house and find a mathematical model of the optimum temperature and humidity for growing mashed mushrooms. Furthermore, find a mathematical model of the yield amount of mashed mushrooms against temperature and humidity. Methods: There are 5 methods in this research, to be composed of studying the problem, planning the operation process, using technology and innovation in smart farms, collecting data and finally finding a mathematical model of the optimum temperature and humidity for growing mashed mushrooms. In addition, a mathematical model of the yield of mashed mushrooms was obtained. Result: The results showed that the mathematical model of the optimum temperature for mashed mushroom was T= 0.3267t3-2.83t2+7.1433t+20, the most appropriate temperature was 24.95±5.557°C at the average andthe mathematical model of the optimum humidity for mashed mushroom was H= -0.8417t3+4.82-0t2.1883t+59.65, the most appropriate humidity was 74.58±15.451% at the average. In addition, the mathematical model of product yield of mashed mushrooms was = -1.479+0.055T+0.028H when temperature T and humidity H were determined.

A Study on the Physiological Diversity of Hand Bathing under Different Conditions

Achieving the best outcomes and ensuring patients are as comfortable as possible are crucial goals for healthcare professionals. Hospital stress has been linked to worsening patient outcomes and so it is important to implement methods for keeping patients calm. Targeting the autonomic nervous system through hand bathing could provide answers. Associate Professor Hajime Nakano and his collaborators at the Faculty of Nursing, Josai International University, Japan, used precise tools to measure the heart rates of patients bathing their hands in waterbaths maintained at carefully controlled temperatures. The researchers used a probe to non-invasively measure brain activation and found that hand bathing decreased sympathetic nervous system activity, increased parasympathetic nervous system activity and produced feelings of relaxation. Nakano and the team conducted another study in which they activated the sympathetic nervous system in volunteers with mental arithmetic and found that hand bathing significantly suppressed the activation. This led them to posit that thermal stimulation has the potential to impact the stress responses in patients and their motivation in a bidirectional manner, which indicated significant possibilities for clinical applications. The researchers are keen to explore how altering the temperature of the hand bath can positively impact patients and an optimum temperature be selected. The team wants to ensure that interventions are tailored to the unique needs of patients and, as such, observed responses under different conditions and collected vast data that has enabled them to consider a research design that accommodated individual differences.

Significant enhancement in the conductivity of highly transparent PEDOT:PSS thin film through Maleic Acid treatment

Abstract The conductivity of poly(3,4-ethylenedioxythiophene):poly(styrene sulfonate) (PEDOT:PSS, a conducting polymer) thin film is enhanced by simply maleic acid treatment. Here, we have investigated the conductivity enhancement with the variation of maleic acid concentration. The conductivity enhances up to 1.0 M maleic acid concentration and decreases afterward. The optimum conductivity is obtained as 9.35 S cm–1, which is nearly 263 times more compared to the pristine PEDOT:PSS film. The conductivity of the film also depends upon the treating temperature. Therefore, the effect of different treating temperatures on the conductivity enhancement is studied, and the optimum temperature is found to be 140°C. Maleic acid-treated PEDOT:PSS films also exhibit high transmittances, i.e., ≈ 90 – 84 % in the visible region. The mechanism related to the conductivity enhancement and other related information are collected through different spectroscopic and microscopic measurements. Besides, frequency-dependant impedance and electrochemical activity of maleic acid-treated PEDOT:PSS films are also performed. The interaction of maleic acid with PEDOT:PSS promotes the reduction of ionic interaction between PEDOT and PSS chains, resulting in the phase separation between PEDOT and PSS. As a result, the PSS– turn into neutral PSSH and is rinsed away by water, which supports the morphological change and the conductivity enhancement due to the conformational change of coil-like PEDOTs to elongated and better-connected PEDOT chains.&amp;#xD;

Endoxylanase Immobilized Nanoporous Silica for the Production of Xylooligosaccharides: Equilibrium Kinetics, Thermodynamic Studies, and Enzyme Characteristics

AbstractNanoporous structured silica materials, namely f‐SiO2, SBA‐15, IITM‐41, and MCM‐41 were employed as the matrices for immobilizing endoxylanase by adsorption method. The equilibrium kinetics, activation energy, and thermodynamic parameters associated with endoxylanase adsorption were investigated. Our findings revealed a two‐phase adsorption mechanism: an initial phase featuring rapid adsorption rates, succeeded by a slower phase wherein adsorption gradually progressed until equilibrium was attained. Analysis of the adsorption kinetic data indicated a better fit with the pseudo‐second‐order model, suggesting chemisorption and highlighting its temperature dependency. The calculated activation energy (Ea) values fell within the range of physisorption, indicating the involvement of both types of adsorption processes. Thermodynamic assessments confirmed that the adsorption reactions were spontaneous, feasible, and endothermic. Notably, the immobilization process did not change the optimum pH of the enzyme, while the optimum temperature shifted slightly. Furthermore, immobilized enzymes show a higher reaction rate (Vmax) than the soluble XynC. All immobilized xylanases produced xylobiose (X2) to xylohexose (X6) by hydrolyzing the xylan substrate. Recycling studies showed that up to 80 % of the yield was retained after seven cycles of reuse. Our study demonstrates the potential of nanostructured silica as an effective immobilization matrix for enzymes of industrial significance.

PURIFICATION OF BETA-GLUCOSIDASE FROM APRICOT SEEDS TO REDUCE THE TOTAL VICINE –CONVICINE CONTENT IN FABA BEANS (VICIA FABA L.)

This research was aimed to purified beta-glucosidase from apricot seeds using ammonium sulfate precipitation, followed by gel filtration chromatography, then ion exchange chromatography. Ion exchange chromatography resulted in the enzyme sample with a specific activity of 41.3 U/mg with a purification fold of 15 and a yield of 30.3%. The apricot beta-glucosidase had an optimum pH of 4 with good stability between pH 3 and 6. The optimum temperature was 60°C and there was good stability between 5 and 40°C. Faba beans treated at pH 5.5 containing beta-glucosidase showed higher total vicine removal than with only water at pH 5.5 after 4 h. Additionally, treatment at 40°C showed higher total vicine removal that treatments at 25°C. However, treating faba beans at pH 5.5 with and without beta-glucosidase resulted in a lower total vicine content for the enzyme treatment before cooking but the total vicine content after cooking was the same for the water treated compared to the enzyme treated. As an industrial by-product, apricot seeds are a rich source of beta-glucosidase that may be used to treat faba beans to increase their nutritional composition.

Production Physiology and Biochemical properties of Crude Thermophile Protease by Mild - Halophilic Bacillus thuringiensis aizawai HD 865

Objective: The current study aims to enrich the research library of Bacillus thuringensis, the most famous bacteria as a biopesticide, with a product that may enhance its ability as a biopesticide as well as its many other applications, namely the heat-tolerant alkaline protease. Methods: The strain Bacillus thuringiensis aizawai HD 865, obtained from HD Culture Collection was grown on a liquid growth medium of nutrient broth and yeast extract, and colonies were counted on agar plates. The zygote is then transferred to a skim milk environment to estimate the enzymatic activity under the different growth conditions of the growth environment (sodium chloride concentration, pH, aeration, fermentation duration), then testing the optimal conditions for enzymatic activity in the enzymatic reaction mixture (sodium chloride concentration, salinity resistance, optimum temperature, thermal stability, optimum pH and stability). Then analyze the data statistically. Results: Optimum alkaline protease medium production conditions were, 2 % NaCl, so Bacillus thuringiensis aizawai HD865 a mild - halophilic microorganism, aeration level 80%, pH 7 and 8 days of fermentation period. On the other hand, crude alkaline protease properties were found that, the optimum temperature for its activity was relatively high (70ºC), while heat-stabilities after 5 min of heating crude enzyme in boiling water bath then incubated for 15min on 30, 40, 50, 60, 70ºC, were 184.23, 178.07, 164.29, 165.51 and 121.46 Units, respectively; whereas the optimum pH was at pH 7.6 (151.76 Units) with tris buffer then at pH 9.6 with glycine - NaOH buffer; While pH stability was at pH 7.6 with tris buffer then at pH 8.4 with glycine - NaOH buffer. Thus, activities have decreased at different concentrations (0, 1, 2, 3, 4, 5 %) of sodium chloride in reaction mixture with enzyme activities (151.25, 137.35, 135.12, 135, 135.89, 114.38 Units) respectively, also decreased when rinse crude enzyme for 5 min in NaCl (0, 1, 2, 3, 4, 5 %), with (151.04, 175.57, 168.69, 154.61, 155.39 and 143.39 Units) respectively. Conclusion: Bacillus thuringiensis aizawai HD 865 strain is considered a low - salt tolerant strain, while the alkaline protease extracted from it is heat - resistant.