Improved computations of the voltage collapse point using the P-index

Online voltage stability assessment of power system is important to ensure reliability and security. Over the years, many voltage monitoring indices have been documented in the literature. These indices are designed to quantify proximity to voltage collapse. However, they all have inaccuracies when predicting the voltage collapse point. A recent research project resulted in a new robust voltage stability monitoring tool called the P-index. A method that utilizes linear approximation of Voltage-Load relationship was introduced alongside the P-index, providing enhanced precision compared to most recognized indices. However, this method generates a high level of inaccuracy because the actual Voltage-Load behavior in general is non-linear, but rather more complex. This study proposed two new models that take into account the nonlinearity of Voltage-Load relationship, providing an enhanced representation of its complexity. Moreover, these models have a higher accuracy in predicting voltage collapse points than the linear method

Physiochemical properties and biological activity of coffee seed fixed oil

هذا البحث اجرى لفحص الخواص الفيزيائية والكيميائية ومكونات الزيت المستخلص من حبوب البن الخضراء، تم الحصول عليها من السوق المحلي للمسعودية، بولاية الجزيرة، السودان. اوضحت النتائج ان نسبة الزيت في البن كانت (3.6617%)، والخواص الفيزيائية كانت: رطوبة الزيت (0.3863%)، معامل الانكسار (1.4643)، اللزوجة (215.47)، الكثافة (0.9081)، اللون: الازرق (4.7)، الاحمر (6.1)، والاصفر (17). الخواص الكيميائية لزيت بذرة البن الخضراء كان رقم الحمض (0.7854)، رقم التصبن (172.5075)، المواد غير المتصبنة (4.7)، رقم اليود (101.52 ملجم / جم)، رقم البيروكسيد (2.25 ملجم / جم). مكونات الزيت بإستخدام كروماتوغرافيا الغاز السائل مع الكتلة الطيفية أعطى 23 مركب. المركبات الرئيسية (اكبر من 10%) كانت حمض اللينوليك (35.30%)،يليه البالماتيك (29.35%)، ثم الاوليك (14.37)، والاستيريك (10.40%). المركبات الثانوية (1- 10%) منها حمض الاراشيديك (4.83%). والبقية كلها توجد في شكل آثار (أقل من 1%) اشهرها حمض البهنيك. النشاط البيولوجي لزيت بذرة البن الاخضر بتراكيز 50%، 25%، 12.5% اعطت أعلى فاعلية في مجال قدره 1.5 مم والاقل في تركيز 100% كان في مجال 0.5 مم بالنسبة لبكتريا (E. coli.). وبالنسبة ل (Peseudomonas) في تركيز 12.5% لم تعطي اي تأثير، وتركيز 25% أعطى مجال تأثير وقدره 1.5 مم ، في 50 % كان مجال تأثيره 1مم، وبتركيز 100% كان مجاله الاقل 0.5 مم. اما في باكتريا (Klebsiella) أعطت معدل تأثير (1.7) في تركيز 100% بينما بقية التراكيز لم تعطي اي تأثير. في حالة بكتريا (Staphylococcus) وفطر (Candida) لم يكن للزيت أي تأثير في جميع التراكيز. ونخلص الى ان الزيت يمكن إستخدامه مضاد ضد انواع البكتريا الثلاثة الاولى

Corona virus 2019 like illness and public adherence to preventive measures, Sudan 2020

Introduction: In December 2019, a novel corona virus disease was identified and was responsible for the new cases of respiratory tract infections in Wuhan, China. This virus was responsible for the pandemic with more than 84 million cases and 1.82 million deaths worldwide. In Sudan till now the reported cases exceed 23,000 with 1.400 deaths. This study aims to determine the prevalence of COVID_19 suspected cases, health seeking behavior and public adherence to protective measures. Methods: Descriptive community based cross sectional study, conducted in Khartoum state 2020. 3499 respondents with diverse socio-demographic backgrounds were finally enrolled in the study. Data was collected through Manitoba Corona Virus 2019 screening form which distributed through online anonymous Google forms. Data was entered and analyzed by Statistical Package of Social Sciences version 23. Results: The study revealed that 26.5% of the respondents were clinically suspected. with headache or fatigability being the most common symptom followed by pharyngitis and then dry cough.  Asthma and chronic respiratory disease as the commonest comorbidities. Wearing facial masks and regular hand washing were found to be the most used protective measures with only 39.4% implicates social distancing in their daily life. Health seeking behavior was significantly different among suspected respondents the majority tend to use antibiotics than to isolate themselves or undergo testing. Conclusion: COVID_19 suspected cases were prevalent among Sudanese population, screening capacity has to be increased with more strong policies for implications of personal protective measures in the daily life.   &nbsp

Geophysical and lithological characterization of the Ellerbek Valley aquifer system

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The capacity of resolution, interpretive efficiency and the quantitative capabilities of GC.MS instrument

In the present study a fast and efficient GC/MS-analysis of a number of volatile and semi-volatile, different classes of organic compounds ranging from simple to complex molecules have successfully been separated, identified qualified and quantified. These compounds are also obtained or extracted from different kinds of naturally occurring origin or industrially manufacture sources e.g. natural products, essential oils, fatty acids in seed oils, pharmaceuticals, drugs, environmental pollutants, pesticides residues, residual solvents in locally manufactured drugs, alkaloids and flavonoids.. In the present study the GC/MS efficiency in terms of resolution of the components of mixtures of these natural products extracts have been tested and the precision of the instrument was confirmed and validated via its ability to identify compounds at level of 1 ng. Moreover the wide range of analytical applications via its capacity to analyzed. In the current research work the following natural products have been analyzed such as caraway oil (Carum Cavi) and Cuminium for essential oils Sesamun seeds oil for fatty acids composition,,Lupin (Lupinus termis) (Cannabis) for alkaloids,Acacia Nilotica for flavonoids ,(Omega 3),(VitaminA) for food supplements, Petrol fraction for hydrocarbons,(Fade Cream),(Sivo Clear), (Max beauty) for cosmetics, (Valproic acid) for drugs, (fish and human serum sample) for pesticide residue. Performing these tests by applying different types of extraction procedures, samples preparation and temperature programs. The laboratory results have revealed the precision capacity, the high resolution capability and accurate structural elucidation power of this highly recommended analytical laboratory technique. The GC-chromatograms and mass spectra of these representative examples have been reported in thi

Effects of skipping one irrigation at different growth stages on yield and water productivity of some maize (Zea mays L.) cultivars under heavy clay soils of central Sudan

      Crop production in arid and semi-arid regions faces the challenge to ensure high yields with limited supply of water. This study was conducted at the experimental farm of the Faculty of Agricultural Sciences, University of Gezira, during seasons 2014/15 and 2015/16. The objectives of this study were to investigate the effects of skipping one irrigation on yield and yield components of maize (Zea mays L.). A split-plot design with four replicates was used. Main plots were assigned to the cultivars namely: Hudaiba1, Hudaiba2 and Mogtamaa -45, and sub-plots to irrigation treatments which consisted of (T1) irrigation every 10 days throughout the season (control), skipping one irrigation at: Vegetative (T2), flowering (T3) and grain filling (T4) stages. The results indicated that irrigation treatments and cultivars had highly significant effects on all parameters tested. Irrigation every 10 days resulted in the highest values of plant height, cob length, number of grains per cob, 100 seed weight, grain yield and water productivity. Hudaaiba2 outyielded the other two cultivars. Skipping one irrigation at flowering (T3) stage gave the lowest values of the tested parameters. The highest grain yield was obtained when frequent irrigation (control) and Hudaiba 2 was practiced and the lowest was obtained by skipping of irrigation at flowering, which reflected the sensitivity of this stage for water deficit. Hence, it is recommended to grow Hudaiba2 maize cultivar and irrigate every 10 days

Role of Amblyomma lepidum in the transmission of Mycobacterium farcinogenes, the causal agent of Bovine farcy

ABSTRACT The present study was conducted to investigate the role of Amblyomma lepidum in the transmission of Mycobacterium farcinogenes, the causal agent of bovine farcy in Sudan. A total of 22 samples comprising of prescapular, submaxillary, mediastinal, parotid, retropharengeal and pulmonary lymph nodes, and subcutaneous nodules were collected for this study. M. farcinogenes was successfully isolated from the specimens by following traditional bacteriological techniques, and the bacteria were identified using standard biochemical assays, lipid analysis using Thin Layer Chromatography, and duplex Polymerase Chain Reaction. Larvae and nymphs of A. lepidum acquired M. farcinogenes from experimentally infected rabbits, and subsequently transmitted the infection to fresh rabbits within a maximum period of ten weeks. In contrast, adult A. lepidum failed to contract the organism from the infected rabbits; so, trans-ovarian transmission could be ruled out. In conclusion, this study confirmed the trans-stadial transmission of M. farcinogenes through larvae and nymphs of A. lepidum