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Petroleum Science 2012年第3期9卷 389-399页

作者： Ahmed El-mekabaty osman m.o.habib Hussein m.Hassan Evelin B.moawad Department of Chemistry Faculty of ScienceMansoura University

oxazolone derivative 2 was utilized as a key intermediate for synthesis of some new oxazolone and imidazolone derivatives. Reaction of oxazolone derivative 2 with diamines under different conditions afforded the corresponding imidazolone derivatives 3-8, respectively. moreover, oxazolone 2 reacted with some heterocyclic amines in glacial acetic acid giving the corresponding imidazolone derivatives 9-14, respectively. Cyclocondensation of thiosemicarbazide with compound 2 in dry pyridine afforded compound 15. Addition of secondary amines to olefin double bond of compound 2 gave the corresponding addition products 16-19, respectively. michael addition of compound 2 with some active methylene compounds afforded oxazolone derivatives 20-23, respectively. These prepared products were evaluated as antioxidant and corrosion inhibitors for gasoline lubricating oil and compounds 6a-e, 10 and 15 exhibited the highest antioxidant and anticorrosive activities. The effect of concentration of additives was studied to recommend the optimum concentration to be used. The results showed, for additive 15, 0.1 g for 1 L oil was the more effective concentration. measurements for thermal analysis and of surface tension of oil after oxidation were also carried out.

关键词： oxazolone imidazolone benzoimidazole surface tension thermal stability antioxidant additives.

Synthesis and evaluation of some novel additives as antioxidants and corrosion inhibitors for petroleum fractions

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Petroleum Science 2014年第1期11卷 161-173页

作者： Ahmed El-mekabaty osman m. o. habib Department of Chemistry Faculty of Science Mansoura University

Benzoxazinone 2 was prepared and reacted with formamide,acetamide,some primary aromatic amines and heterocyclic amines giving the corresponding quinazolone derivatives 3-15 *** reaction of benzoxazinone 2 with hydrazine hydrate and phenyl hydrazine was also *** compounds of the synthesized products were evaluated as antioxidants and corrosion inhibitors for gasoline engine lubricating *** highest antioxidant activities were obtained with compounds *** optimum concentration recommended for these new additives was found to be *** for 1L ofoil for compounds *** addition,some of the highly effective antioxidant additives,namely 10-15,were thermally analyzed by using thermogravimetric analysis （TGA） and differential thermal gravimetric analysis （DTGA） techniques and the results indicated that compounds are thermally stable and could be used under thermal ***,a comparison of the oxidation stability between the tested oil containing the prepared products and lubricating oil containing commercial additives was also studied.

关键词： Benzoxazinone quinazolinone thermal stability antioxidant additives anticorrosive additives

Ru/NimnB spherical cluster pillar for highly proficient green hydrogen electrocatalyst at high current density

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Journal of Energy Chemistry 2025年第1期100卷 397-408页

作者： md Ahasan habib Shusen Lin mehedi Hasan Joni Sumiya Akter Dristy Rutuja mandavkar Jae-Hun Jeong Jihoon Lee Department of Electronic Engineering College of Electronics and Information Kwangwoon University

Advanced oER/HER electrocatalytic alternatives are crucial for the wide adaptation of green hydrogen ***,Ru/NimnB spherical cluster pillar （SCP）,denoted as Ru/NimnB,is synthesized using a combination of electro-deposition and hydrothermal *** investigation of Ru doping in the NimnB matrix revealed significant improvements in electrocatalytic *** Ru/NimnB SCPs demonstrate superior oER/HER activity with low overpotentials of 150 and 103 mV at 50mA/cm2in 1 m KoH,making them highly competitive with state-of-the-art ***,the Ru/NimnB SCPs exhibit a low 2-E cell voltage of 2.80 V at ultra-high current density of 2,000 m A/cm2in 1 m KoH,outperforming the standard benchmark electrodes of Ruo2||Pt/C,thereby positioning Ru/NimnB as one of the best bifunctional *** SCPs exhibit exceptional high-current characteristics,stability and corrosion resistance,as evidenced by continuous operation at 1,000 mA/cm2high-current density for over 150 h in 6 m KoH at elevated temperatures under harsh industrial *** a small amount of Ru incorporation significantly enhances the electrocatalytic performances of NimnB,attributed to increased active sites and improved intrinsic properties such as conductivity,adsorption/desorption capability and reaction ***,Ru/NimnB SCPs present a promising bi-functional electrode concept for efficient green H2production.

关键词： Advanced electrocatalyst High current Corrosion resistance Industrial requirement

Inhibition of Ehrlich ascites carcinoma by manilkara zapota *** bark in Swiss albino mice

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Asian Pacific Journal of Tropical Biomedicine 2011年第6期1卷 448-451页

作者： m Abu osman m mamunur Rasbid m Abdul Aziz m Rowshahul habib m Rezaul karim Department of Biochemistry and molecular Biology Faculty of ScienceRajshahi University

objective:To evaluate the antitumor activity of manilkara zapota(***) *** bark against Ehrlich ascites carcinoma(EAC) in Swiss albino ***:The in vivo antitumour activity of the ethyl acetate extract of stem bark of *** L.(EASm) was evaluated at 50,100 and 200 mg/kg bw against EAC using mean survival *** administration of the extract of ***,viable EAC cell count and body weight in the EAC tumour hosts were *** animal was also observed for improvement in the haematological parameters(e.g.,heamoglobin content,red and white blood cells count and differential cell count) after EASm treatment. Results:Intraperitoneal administration of EASm reduced viable EAC cells,increased the survival lime,and restored altered haematological *** efficacy was observed for EASm at 100 mg/kg dose(Ponclusions:It can be concluded that the elhyl acetate extract of stem bark of *** *** significant antitumour activity.

关键词： manilkara zapota Antitumour activity Stem bark Ehrlich ascites carcinoma Haematological parameter

Identification of pulse-like ground motions using artificial neural network

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Earthquake Engineering and Engineering Vibration 2022年第4期21卷 899-912页

作者： Ahed habib Iman Youssefi mehmet m.Kunt Department of Civil Engineering Eastern Mediterranean University99628 FamagustaNorth Cyprusvia Mersin 10Turkey

For more than 20 years,the concept of near-fault pulse-like ground motion has been a topic of great interest due to its distinct characteristics,particularly due to directivity or fling effects,which are hugely influenced by the rupture *** unexpected characteristics,along with their effective frequency,energy rate,and damage indices,create a near-fault,pulse-like ground motion capable of causing severe damage to *** of the most common approaches for identifying these ground motions is done by conducting wavelet decomposition of the ground motion time history to extract a pulse signal and eventually categorize an earthquake by comparing the original signal to the residual ***,to overcome the intensive calculations required in this approach,this study proposes using artificial neural networks to identify pulse-like ground motions through classification to predict their pulse period by means of regression ***,the study is intended to evaluate the reliability and accuracy of various artificial neural networks in identifying pulse-like ground motions and predicting their pulse *** general,the results of the study have shown that the artificial neural network can identify pulse-like earthquakes and reliably predict their pulse period.

关键词： pulse-like ground motions near-fault artificial neural network identification

Evaluation of antitumour activity of Calotropis gigantea *** bark against Ehrlich ascites carcinoma in Swiss albino mice

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Asian Pacific Journal of Tropical medicine 2011年第10期4卷 786-790页

作者： m Rowshahul habib m Rezaul karim Department of Biochemistry and molecular Biology Faculty of ScienceRajshahi UniversityRajshahi-6205Bangladesh

objective:To investigate experimentally the possible antitumor effect of methanol extract(mE) of Calotropis gigantea L.(***) root bark and its petroleum ether(PEF) and chloroform(CF) soluble fractions against Ehrlich ascites carcinoma(EAC) in Swiss albino ***:The effects of mE(10 and 20 mg/kg),PEF(40 and 80 mg/kg) and CF(20 and 40 mg/kg) on the growth of EAC and life span of EAC bearing mice were *** profile and biochemical parameters(SAI.P,SGPT and SCoT) were also ***:Results of in vivo study showed a significant decrease in viable tumor cell count and a significant increase of life span in the mE and CF treated group compared to untreated *** life span of mE and CF treated animals was significandy(Pmg mE/kg) and 57.07%(40 mg CF/kg).mE and CF brought back the hematological parameter more or less normal *** and CF also restored the altered levels of serum alkaline phosphatase(SALP) and serum glutamate oxaloacetate transaminase(SGoT).Conclusions:methanol extract(mE) of *** root bark and its chloroform soluble fraction(CF) possesses significant antitumor activity.

关键词： Calotropis gigantea Antitumor Ehrlich ascites carcinoma Root bark

Convective Transport in Rectangular Cavities Partially Heated at the Bottom and Cooled at one Side

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Journal of Thermal Science 2013年第1期22卷 55-63页

作者： C.Cianfrini m.Corcione E.habib A.Quintino DIAEE Sezione Fisica Tecnica Sapienza Università di Roma

Laminar natural convection heat transfer inside air-filled, rectangular enclosures partially heated from below and cooled at one side is studied numerically. A computational code based on the SImPLE-C algorithm is used for the solution of the system of the mass, momentum, and energy transfer governing equations. Simulations are performed for a complete range of heater size, for Rayleigh numbers based on the height of the cavity ranging from 10~3to 10~6, and for height-to-width aspect ratios of the cavity spanning from 0.25 to 4. It is found that the heat transfer rate increases with increasing the heater size and the Rayleigh number, while it decreases with increasing the aspect ratio of the cavity. Dimensionless heat transfer correlations are also proposed.

关键词： natural convection enclosure partial heating numerical analysis dimensionless correlations

Effects of the Aspect Ratio on the optimal Tilting Angle for maximum Convection Heat Transfer across Air-filled Rectangular Enclosures Differentially Heated at Sides

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Journal of Thermal Science 2017年第3期26卷 245-254页

作者： C.Cianfrini m.Corcione E.habib A.Quintino DIAEE-Sezione Fisica Tecnica Sapienza Universita di Roma via Eudossiana18-00184 RomeItaly

Natural convection in air-filled rectangular cavities inclined with respect to gravity, so that the heated wall is facing upwards, is studied numerically under the assumption of two-dimensional laminar flow. A computational code based on the SImPLE-C algorithm is used for the solution of the system of the mass, momentum and energy transfer governing equations. Simulations are performed for height-to-width aspect ratios of the enclosure from 0.25 to 8, Rayleigh numbers based on the length of the heated and cooled walls from 10~2 to 10~7, and tilting angles of the enclosure from 0° to 75°. The existence of an optimal tilting angle is confirmed for any investigated configuration, at a location that increases as the Rayleigh number is decreased, and the height-to-width aspect ratio of the cavity are increased, unless the value of the Rayleigh number is that corresponding to the onset of convection or just higher. Dimensionless correlating equations are developed to predict the optimal tilting angle and the heat transfer performance of the enclosure.

关键词： Natural convection in air Tilted cavity Differential heating Numerical analysis Dimensionless correlations

Two New Records of Snapper(Perciformes, Lutjanidae) from Saint martin's Island, Bangladesh

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Journal of ocean University of China 2021年第2期20卷 439-444页

作者： SARKAR Provakar ISLAm md Jayedul habib AHmShafiullah NEoGI Amit Kumer habib Kazi Ahsan Department of Zoology Jagannath UniversityDhaka 1100Bangladesh Aquatic Bioresource Research Laboratory Department of Fisheries Biology and GeneticsSher-e-Bangla Agricultural UniversityDhaka 1207Bangladesh Department of Fisheries Biology and Genetics Faculty of FisheriesAquaculture and Marine ScienceSher-e-Bangla Agricultural UniversityDhaka 1207Bangladesh

The present work documented two snapper species, Lutjanus fulvus Forster, 1801 and Lutjanus erythropterus Bloch, 1790, recently collected from the Saint martin's Island, Bay of Bengal, Bangladesh, during a survey on coral associated fishes of Bangladesh from July 2017 to September 2018. These two species were identified with morphological characteristics and by analyzing partial mitochondrial CoI sequences. The document also included an updated checklist of snappers available in Bangladesh.

关键词： Lutjanus fulvus Lutjanus erythropterus DNA barcoding Bay of Bengal

Body mass Index and Body Fat Percentage in Assessment of obesity Prevalence in Saudi Adults

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Biomedical and Environmental Sciences 2013年第2期26卷 94-99页

作者： Syed Shahid habib Department of Physiology College of Medicine&King Khalid University HospitalKing Saud University

objective To assess the obesity prevalence in body mass index （BmI） and body fat percentage Saudi adults according to the international standards of （BF%）. methods Five hundred and thirty healthy Saudi adults aged 18-72 years （mean 36.91＋15.22 years） were enrolled in this study. Their body composition was assessed by bioelectrical impendence analysis with a commercially available body composition analyzer. Standard BmI and BF% values were used to define obesity. Results The prevalence of underweight, normal underweight, overweight and obesity in Saudi adults according to the BmI criteria （〈18.5 kg/mz, 18.5-24.4 kg/m2, 25-29.9 kg/m2, 30 k＆/m2 and above, respectively） was 2.5%, 30.2%, 33.6%, and 33.8%, respectively, whereas the obesity prevalence was 60% （n=31g） in Saudi adults according to the BF% criteria （25% for males and 30% for females）, which was significantly higher than that according to BmI criteria. However, it was 50.6% （n=268） when the BmI cutoff point was 27.5 kg/m2, proposed by WHo for the Asian population. Kappa analysis showed that the obesity prevalence defined by BmI and BF% was higher in females than in males （k=0.530 vs k=0.418, P〈o.o001）. The sensitivity and specificity of BmI （30 kg/m2 and 27.5 kg/m2） were 54.1% and 96.7% and 76.4% and 88.2%, respectively, for obesity. A lower BmI cutoff point （26.60 kg/m2） was proposed in this study, which gave the maximum sensitivity （84.3%） and specificity （85.4%）, with a moderate kappa agreement （k=0.686）. moreover, the obesity prevalence at this cutoff point （56.4%） was significantly higher than that recommended by WHo. Conclusion The specificity of BmI for obesity is high and its sensitivity is low in both sexes. Its sensitivity can be increased by changing BmI cutoff to a lower value. The choice of BF% reference is of great influence for the assessment of obesity prevalence according to the BmI.

关键词： Body composition obesity Body mass index Body fat percentage Kappa analysis