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A Study on Pesticide Sprayer Powered by Solar Energy Appropriate for Small Farms
2021
AHMED El-Sayed | Abdel-Fadil Kabany | Waleed Elhelew
The study was conducted on a knapsacksprayer powered by a DC motor through a 12 V lead acid battery charged from a solar panel (photovoltaic) directed to sun rays. The system was installed and tested in the western desert on a small-scale farm at Frafra Oasis (New val-ley). This study aimed to evaluate and develop a knapsack sprayer powered by a solar energy for overcoming operator fatigue and shortage of traditional energy in Egypt’s western desert. The experiments were conducted during the period which starts in August 2019 till Febru-ary 2020. The main parts of the system consist of photovoltaic (PV) or solar cells, charger controller, rechargeable battery, and DC motor speed control with dimmer and pump which was attached with a tank 20 liters capacity for sucking and pressurizing the liquid to the boom of the sprayer through a flexible hose. The main results of experiments were as fol-lows: The time for recharging the battery com-pletely was found 330 minutes (5.5 hours) to charge completely from 10.55 V – 13.85 V, with current intensity 1.67 Ampere. The bat-tery discharge time was varied due to drop the battery voltage from 13.85 – 10.55 Volts. De-pending on the motor speed, which is the time for discharging the battery was found 4 – 9 hours, when motor pulled 0.85 - 1.85 Amps at 2000 - 3400 rpm and this time at deferent speed is enough to spray area 3 - 6.82 fed/day "day work = 6 hours" with application rate 67 - 104.7 l/fed. The number of droplets and the area coverage percentage ranges from 30 – 146.33 drops and 13.96 – 27.97% for one cm2 of simulator targets at a speed ranging from 2000 – 3400 rpm, respectively.
Mostrar más [+] Menos [-]Genotoxic Effects and Liver Toxicity in Swiss Albino Mice Males after Acute and Chronic Exposure of Diacetyl and Butter flavors
2021
Mohamed AboelMaaty | neima Elsenousy | Naglaa Ebeed | Khalid Fahmy
Since the mid-1950s, the volatile structure of butter oil and butter were researched, and an exhaustive list of elements has been collected. Diacetyl is an aromatic popular synthetic fragrance that gives food a buttery taste used in ice cream, snacks and potting with butter, strawberry, caramel, or cheese flavor. The chromosomal aberrations and micronuclei are commonly used biomarkers of chromosomal damage, genome stability, and cancer risk assessment.In vivo trials are still important to assess the genetic toxicology of chemical products such as industrial chemicals, pharmaceuticals, and food additives. This study aimed at assessing the potential genotoxic effect of diacetyl and butter flavors on swiss albino mice using alterations in liver function enzymes, micronucleus (MN), and chromosomal aberrations (CA) assays. The results showed that exposure of swiss albino mice malesto diacetyl and butter flavors induced (CA) and (MN) in a statistically highly significant manner compared to the control. Meanwhile, the biochemical analysis revealed that these substances caused an exceptional rise in liver function enzymes (AST, ALT, and ALP) activity in serum of treated experimental animals.In conclusion, both tested compounds have increased the chromosomal aberration, micronucleus test, and serum levels of liver function enzymes indicating their high potential of being cytotoxic and genotoxic materials.
Mostrar más [+] Menos [-]Effect of Different Dried Methods and Storage on Some Enzymes Activity and Quality of Cactus pear and Papaya
2021
Marwa Abdel-Hady | magdy El-shemy | samar Mahdy | Effat rizk
This study was to evaluate the activity of peroxidase, polyphenoloxidase, pectin methyl esterase and protease as well as the proximate chemical composition and quality parameters of cactus pear and papaya which were dried by different methods and stored for 6 months. Our findings revealed that the highest moisture content was recorded in osmo – freeze drying of papaya and cactus pear. On the other hand, the browning index of oven dried papaya and cactus pear was higher than those dried with osmotic dehydration and osmo – freeze drying. The less activity of peroxidase was recorded in osmo – freeze drying of papaya and cactus pear. Also, the highest reduction of polyphe-noloxidase activity was noticed in osmo–freeze drying methods. While oven dried pa-paya recorded the highest activity of pectin methyl esterase pectin (0.34 %), complete in-activation was shown in other dried methods after 6 months of storage at 4 ±1℃. Different dried methods of papaya caused to reduce the activity of protease, moreover, complete inac-tivation was observed after 3 months from storage. The quality parameters for sensory evaluation of dried cactus pear and papaya demonstrated that osmo–freeze drying was more favorable to preserve samples followed by osmotic dehydration and oven drying.
Mostrar más [+] Menos [-]Biomass Production of Microalgae using Agricultural and Industrial Wastewater
2021
Merihan Abdel-Raouf | Sohair Nasr | Elham Aref | Khadiga Aboutaleb
Growing wastewater microalgae contrib-utes to the elimination of nutrients present in wastewater because they need N and P for the synthesis of proteins, nucleic acid, and phos-pholipids. The most sustainable approach for achieving high biomass and high lipid build-up, along with environmental protection. In the current research, nine microalgae were culti-vated on two variations of wastewater (agricul-tural and industrial dyes) and compared to the synthetic medium. The results indicated that after three weeks of the incubation period, the ability of microalgae to grow in sterilized (syn-thetic medium and wastewater) and gave greater biomass and chlorophyll (a) than in non-sterilized ones. Out of the tested nine mi-croalgae, four microalgae (Anabaena oryzae, Spirulina platensis, Anabaena sp (2) and Nos-toc sp) were selected which gave the highest significant values of dry weight, biomass productivity and chlorophyll (a) content. The selected microalgae showed the highest signif-icant values of the chemical composition, i.e., total carbohydrate, protein and lipid when cul-tivated in agricultural wastewater more than those cultivated in both industrial dye’s wastewater and synthetic broth medium. Among four microalgae, two microalgae of A. oryzae HSSASE6 (KT277789), and S. platen-sis NIES-39 (A00800) were chosen where the chemical composition contents ranged from 1.17 to 1.21-fold and 1.03 to 1.06-fold of car-bohydrate, 1.06 to 1.09-fold and 1.88 to 1.93-fold of protein and 1.41 to 1.52-fold and 1.76 to 1.90-fold of lipid more than those of other microalgae, respectively. The agriculture wastewater was inoculated with a single cul-ture of A. oryzae HSSASE6 (KT277789) or S. platensis NIES-39 (A00800) individually with 10 % of inoculum size, which more preferred than was inoculated with consortia culture. Re-sults also showed that A. oryzae HSSASE6 (KT277789) was more efficient strain for giv-ing biomass and productivity in agricultural wastewater than S. platensis NIES-39 (A00800) (about 28% more).
Mostrar más [+] Menos [-]Effect of Electrolysis Technology on Saline Water under Utilize Nano-coated Electrodes
2021
Mohamed Hassan | Arafa Yasser | Khaled elbagoury
In this work, electromagnetic field technol-ogy and electrolysis technology with alumi-num electrodes coated with titanate nano-coat-ing were combined in different investigated parameters: power types (Electrolysis pass (EP) and Electromagnetic pass (EMP)), volt-age (12v, 24v and 36v) and nano-coating pa-rameters (coated and uncoated). The designed water treatment unit was evaluated by record-ing the EC-meter readings for 60min (each 5min) at a flow rate of 5l/min. Results show that the best salt rejection rate was 3.4% when EMP was used before EP where four elec-trodes were coated. In contrast, the other pa-rameters (EP, EMP+EP and EMP+EP (2 coated electrodes and 2 uncoated)) recorded the salt rejection rates 1.13%, 1.57% and 2.4%, respectively. This study is promising and opens the way for integrating both electrolysis and electromagnetic field technologies with on-farm irrigation systems and enhancing their efficiency using nanotechnology.
Mostrar más [+] Menos [-]Nitrogen Nutrition and Adaptation of Halophyte Chenopodium quinoa to Salt Stress
2021
Karema Tarek | Ibrahim Alshamy | Sayed Hussin | Sayed Eisa
There is little evidence that the nitrogen nu-trition supply at rates above or less than what is considered optimal in non-saline conditions improves growth and yield of halophyte crop cultivated under salt stress. Therefore, hypoth-esize of the present work was to find out the magnitude to which N could restore the harm-ful effects of salt stress on quinoa plants. A pot experiment was performed in greenhouse con-ditions to evaluate quinoa's response grown under water salinity treatments (0.0 & 200 mM NaCl) when nitrogen nutrition rates were limiting (50ppm), adequate (250 ppm), and ex-cess (450 ppm) to guide proper application rate of nitrogen fertilizer under salinity stress. The results indicated that, salinity caused a signifi-cant decrease in the vegetative growth of the plant. Consequently, all vegetative measure-ments were negatively affected. As a result, the seed yield decreased to more than 50%. The application of a moderate level of nitrogen (250 ppm) caused a significant ameliorative effect on seed yield by 126% under non saline conditions and 34.5 % under saline conditions compared to the low nitrogen level. The results did not improve any further with the applica-tion of a higher level of nitrogen. These results indicate that applying (N) in adequate may im-prove most traits and prove to be a physiolog-ical treatment to increase resistance against the negative effects of salt stress in quinoa.
Mostrar más [+] Menos [-]A Comparative Study Between Different Preservation Methods on The Viability of Some Yeast Cultures
2021
Reham Abdallah | Ibrahim Sayed Ahmed | amal hassan | hemmat Elshesheetawy
The influence of chilling, freezing, and dry-ing preservation methods on morphological properties and viability of four yeast cultures, isolated Saccharomyces boulardii (SB1 and SB2), Saccharomyces cerevisiae (SC), and Kluyveromyces lactis (KL), was studied. chilling preservation had no effect on yeast colony morphology parameters till the end of the preservation period in contrast with freez-ing and drying preservation methods. Drying preservation resulted in the highest viability decrement % of yeast cultures ranged between 59.38 to 40.21% as compared with other preservation methods. There is a noticeable re-duction in D values of preserved yeast cultures by drying, which varied from (33 to 26 day) in comparison to chilling and freezing preserva-tion that recorded (119 to 83 and 180 to 57 day), respectively. The obtained results re-vealed that chilling preservation under proper conditions, as well as freezing, is more prefer-able for the preservation of studied yeast cul-tures than that preserved yeast by the drying method.
Mostrar más [+] Menos [-]Greenhouse and Laboratory Evaluation of The Efficiency of Green Silicon Dioxide Nanoparticles Against Tetranychus urticae (Koch)
2021
Heba Emam | Manal Ibrahim | Mervat Ibrahim | Salwa El-Sayed
Nanotechnology takes a significant position in controlling pests. Silicon dioxide nanoparticles (SiO2-NPs) is considered one of the best alter-natives to chemical pesticides for plant crop protection from harmful arthro-pods such as phytophagous mites, Tetranychus urticae. Therefore, this study aims to evaluate the effect of (SiO2-NPs) to control T. urticae. Under green-house conditions, the results revealed, in the larval stage, a high mortality percentage (99.05±0.83%) followed by eggs (98.74±1.22%). Besides, the nymph stage recorded high mortality (94.66±1.81%) at a high concentration of 1500 ppm. While the adult females of T. urticae recorded mortality of 91.92±1.02% after 72h. Eventually, the immature stages of T. urticae were susceptible to (SiO2-NPs). Meanwhile, at laboratory evaluation on immature stages of T. urticae which resulted from live treated females during 96h showed a sharp decrease in average numbers of eggs through 96h, at 1000 and 1500 ppm. No numbers of the larval stage were recorded at 1500 ppm. No number of nymph stage were recorded at all concentrations and periods. Moreover, activity of AChE was significantly inhibited at 1500 ppm, while activity of glutathione-S-transferase was significantly increased after 72 h. Finally, (SiO2-NPs) are effective against immature stages of T. urticae under greenhouse and laboratory conditions.
Mostrar más [+] Menos [-]Management of Irrigation Water for Cucumber Crop by Using Drip Irrigation Systems under Greenhouse
2021
Esraa Masria | Abdelghany Elgandy | Khaled elbagoury | essam wasif
This study aimed to examine the consequences of three regimes for irrigation on cucumber crops and their growth indication, production, and water productivity under greenhouse cultivation. Cucumber seedlings were planted in May 2018 under a greenhouse condition. Three regimes of drip irrigation were examined, first 100%, 80%, and 50% of ETc namely T1, T2, and T3, respectively. The second regime was systems of drip irrigation (sur-face and sub-surface irrigation). Finally, the third was dripper discharge which used (2 l/h and 4 l/h). Results indicated clearly that the best production was under 80% ETc regime by 2 l/h dripper for surface and subsurface that was 10.1 and 11.2 ton/greenhouse respectively with IR 172 m3/season and the best regime by using 4 l/h was 50% ETc for surface and sub-surface respectively which was 11 and 11.5 ton/greenhouse with IR 216 m3/season which saved about half a quantity of irrigation water. On the other hand, the very best water productivity value (WP) was under 80% ETc was 58.7 and 65.4 kg/m3 under surface (S) and sub-surface (SS) drip irrigation respectively by 2 l/h dripper flow rate.
Mostrar más [+] Menos [-]Evaluation of Some Adjuvants in Improving Foliar Fertilizers Efficiency
2021
Dina Omran | Ahmed Ibrahim | Manal Mohamed | Mona Nossier
A series of lab and field experiments were carried out to evaluate the possibility of using some substances as adjuvants added to the foliar fertilizer tank to improve fertilizer application and enhance use efficiency. Each of the suggested substances was prepared in 10 concentrations treatments, ranging between 0.05 and 2g/L. The effect of each concentration on static surface tension and static contact angle in liquid/air/glass and solid plant leaves/air interface were used to evaluate and find out the optimum concentration of each substance to be used as an adjuvant. An Adjmix-D1 was pre-pared using 0.6g/L Triethanolamine and 0.6g/L liquid soap as surfactants, 0.6g/L glycerin as a humectant, 0.6 g/L Arabic gum as a sticker and 0.6g/L urea as a penetrator. The obtained results showed that fruit yield as well as N, K, Fe, Zn and Mn contents in white eggplants and cucumber leaves are positively increased by the applications of improved foliar fertilizers (IFF). This increase can be arranged in the following descending order: Adjmix-D1 > Adjmix-D2 > Liquid soap > Rixi film > Triethanolamine. It could be concluded that the Adjmix-D1 can be used as an effective adjuvant for improving foliar fertilizer application efficiency.
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