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Synthesis and Characterization of Polyesters Based on Diethylketone moiety

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Chinese Journal of Polymer Science 2014年第11期32卷 1450-1459页

作者： Ismail A.Alkskas Bashir A.El-gnidi Khadija m.Ghalieo Faizul azam Polymer Lab Department of ChemistryFaculty of ScienceMisurata University Faculty of Pharmacy Misurata University

A new class of unsaturated polyesters based on diethylketone have been prepared by interfacial polymerization of 2,4-bis（4-hydroxybenzylidene）-3-pentanone（I） and 2,4-bis（4-hydroxy-3-methoxybenzylidene）-3-pentanone（II） with 4,4’-azodibenzoyl chloride and 3,3’-azodibenzoyl chloride at ambient temperature. The model compounds were synthesized by reaction of（I） and（II） with benzoyl chloride. The new monomers, model compounds and polyesters have been characterized by different spectral analyses. The polyesters have inherent viscosity of 0.55-0.80 d L/g and moderate number average molecular weight（mn） in the range of 6150-7400 g/mol. most of the compounds exhibited their solubility in aprotic solvents while partial solubility in various halogenated organic solvents was observed. The temperatures of 10% weight loss were high（225-330 °C） in nitrogen, indicating that these polyesters have excellent thermal stability. Doping with iodine dramatically raised the conductivity and produced brown colored semiconductive polymers with a maximum conductivity of 2.7 × 10-6 --1cm-1. moreover, the morphological properties of selected example of polyesters were detected by SEm.

关键词： Diethylketone Azo Polyesters Conductivity.

Determination of consolidation behaviour of clay slurries

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International Journal of mining Science and Technology 2016年第2期26卷 277-283页

作者： Khan Faseel S. azam Shahid Environmental Systems Engineering University of Regina

The main objective of this study was to determine the consolidation behaviour of clay slurries.A finegrained clay with high consistency limits(W_L = 180%,w_P= 120%) was investigated using conventional oedometer and bench-top centrifuge *** indicated that the slurry had an apparent preconsolidation(due to initial conditions,electrochemical interactions,tortuous drainage,and thixotropic strength) from e = 5.7 to e = 5.5 followed by virgin ***,the low hydraulic conductivity(10^(-10)-10^(-12) m/s) was due to low porosity(small pore throats) and high tortuosity(long flow paths).Unlike consolidation of soils,the c_v and m_v decreased with increasing σ' but increased with increasing e and *** data from the two tests correlated well in the range of σ' = 10-65 kPa,e = 5.5-3.86,k= 1.7 × 10^(-10)-5×10^(-11) m/s,F_c = 1-40 *** equations were developed to correlate the consolidation parameters(e,σ',k) with F_*** deviation of k beyond 40 mN(e = 4.65) was due to deviation from the initial straight line portion of the settlement curve in the centrifuge test.

关键词： Clay slurry Consolidation Conventional oedometer test Bench-top centrifuge

Description and characterization of place properties using topic modeling on georeferenced tags

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Geo-Spatial Information Science 2018年第3期21卷 173-184页

作者： azam R.Bahrehdar Ross S.Purves Department of Geography University of ZurichZurichSwitzerland

User-Generated Content(UGC)provides a potential data source which can help us to better describe and understand how places are conceptualized,and in turn better represent the places in Geographic Information Science(GIScience).In this article,we aim at aggregating the shared meanings associated with places and linking these to a conceptual model of *** focus is on the metadata of Flickr images,in the form of locations and *** use topic modeling to identify regions associated with shared *** choose a grid approach and generate topics associated with one or more cells using Latent Dirichlet *** analyze the sensitivity of our results to both grid resolution and the chosen number of topics using a range of measures including corpus distance and the coherence *** a resolution of 500 m and with 40 topics,we are able to generate meaningful topics which characterize places in London based on 954 unique tags associated with around 300,000 images and more than 7000 individuals.

关键词： Place property topic modeling Volunteered Geographic Information(VGI) tagging

Linking basin-scale hydrology with climatic parameters in western Himalaya:Application of satellite data,temperature index modelling and in-situ observations

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Geoscience Frontiers 2024年第6期15卷 528-544页

作者： Smriti Srivastava mohdFarooq azam Praveen Kumar Thakur The Wilkes Centre for Climate Science and Policy University of UtahSalt Lake CityUSA School of Environment Society and SustainabilityUniversity of UtahSalt Lake CityUSA Department of Civil Engineering Indian Institute of Technology IndoreIndia Department of Water Resources Indian Institute of Remote Sensing(IIRS)ISRODehradunIndia

Due to limited spatial and temporal in-situ runoff data availability,Himalaya-Karakoram(HK)glaciohydrology has a significant knowledge gap between large-scale and small-scale runoff modelling *** study reconstructs longest basin-wide runoff series in Chandra-Bhaga Basin by applying a high-resolution glaciohydrological model SPHY(Spatial Processes in Hydrology)over 1950–***-tier model calibration is done using in-situ basin-wide runoff(1973–2006)and mODIS snow cover(2003–2018).model validation is done against in-situ Chhota Shigri Glacier catchment-wide runoff(2010–2015).The modelled mean annual basin-wide runoff is 60.21±6.17 m^(3)/s over 1950–2022,with maximum runoff in summer-monsoon months,peaking in July(182.69 m^(3)/s).Glacier runoff(ice melt+snowmelt over glacier)contributes maximum(39%)followed by equal contributions from snowmelt runoff from non-glacierized basin area and baseflow(25%),while rainfall-runoff contributes minimum(11%)to total *** is a significant volumetric increase by∼7%from pre-(59.17 m^(3)/s)to post-2000(63.47 m^(3)/s)mainly because of early onset of snowmelt post-2000 that resulted in a hydrograph shift by∼25 days earlier in *** glacier runoff is overestimated by 3%from RGI 7.0 inventory compared to different manually delineated inventories over 1950–2022,because of higher glacierized area from RGI *** precipitation shows a negative trend,but total runoff shows a positive trend due to positive trend of temperature that resulted in more glacier runoff and rainfall-runoff for basin over last 72 ***-wide runoff is mainly governed by summer temperature which directly controls the amount of glacier and snowmelt runoffs and is supported by summer *** study highlights importance of basin-scale model calibration with in-situ data in large scale studies and stresses the need for in-situ observations in high-altitude Himalayan ***-scale calibrated model parameters are transferable to glacie

关键词： Himalaya Glaciohydrological model Glacier runoff Baseflow Pre-and post-2000 Chandra-Bhaga Basin

Effects of salt and nitrogen on physiological indices and carbon isotope discrimination of wheat cultivars in the northeast of Iran

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Journal of Integrative Agriculture 2020年第3期19卷 656-667页

作者： azam BORZOUEI mirAhmad mOUSAVI SHALmANI Ali ESKANDARI Nuclear Agriculture Research School Nuclear Science and Technology Research Institute(NSTRI)

In order to study the effects of different levels of salt stress and nitrogen(N) on physiological mechanisms,carbon isotope discrimination(△13C),and yield of two wheat cultivars(cv.),a two-year field experiment was carried out during *** treatments included three levels of salt stress(1.3,5.2,and 10.5 dS m^-1),three levels of N(50,100,and 150 kg N ha-1),and two wheat cultivars,Bam and *** salt stress,N application(100 and 150 kg N ha^-1) produced a significant effect on both cultivars with respect to physiological traits,i.e.,net photosynthetic rate(Pn),stomatal conductance(gs),chlorophyll index(Cl),Na^+/K^+ ratio as well as the grain yield(GY).The salt-tolerant and-sensitive cultivars exhibited the maximum values of physio-biochemical and yield attributes at 100 and 150 kg N ha-1,*** results of △13C showed a significant difference(Pm seems to be more efficient in terms of higher GY,Pn,gs,Cl,and lower Na^+/K^+ ratio as well as higher △13C as compared with salt-sensitive cultivar Toos,under salt ***,a significant positive correlation that observed between △13C and GY,indicated that △13C may be an effective index for indirect selection of yield potential in wheat under irrigation regimes with saline water.

关键词： net photosynthetic rate stomatal conductance chlorophyll index carbon isotope discrimination

Intestinal protozoa and intestinal helminthic infections among schoolchildren in Central Sudan

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Asian Pacific Journal of Tropical medicine 2010年第4期3卷 292-293页

作者： Abdel-aziz m.Ahmed azam A.Afifi Elfatih m.malik Ishag Adam University of Khartoum Sudan Preventive medicine Federal Ministry of HealthSudan

Objective:To determine the prevalence of intestinal parasitic infections and soil-transmitted helminths(STHs) among primary schoolchildren in El dhayga,Central ***:In this cross-sectional study,three fresh faecal samples were collected from each child,which were examined by direct wet mount,brine flotation,formalin-ether and Kato-Katz *** intensity of each STH infection was expressed as the mean of eggs per gram counts of the three ***:In total,142(90.4%) of 157 children harboured at least one type of intestinal *** lumbricoides,Hymenolepis nana,Entamoeba histolytica and Giardia lamblia were the most common parasites found,with prevalence rates of 32.5%,30.6%,33.1%and 19.7%,*** of these 157 children,29(18.5%) harboured more than two intestinal parasitic *** cases of Schistosoma mansoni or Enterobius vermicularis were identified. Conclusions:The study demonstrates significant burden of intestinal protozoa and STH infections in this part of Sudan and highlights the need for preventive and intervention measures.

关键词： Schoolchildern Helminthes Intestinal Protozoa Sudan

Geotechnical behavior of uranium mill tailings from Saskatchewan,Canada

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International Journal of mining Science and Technology 2016年第3期26卷 369-375页

作者： Bhuiyan Imteaz azam Shahid Khaled Shifullah Landine Patrick Environmental Systems Engineering University of Regina Thurber Engineering Limited Cameco Corporation

This paper investigates the geotechnical behavior of uranium mill tailings from Saskatchewan, *** 4% tailings were well-graded with 29% fines whereas the 5% and 6% tailings were gap-graded with 49% fines. All samples exhibited a negligible strength(0.4 k Pa) up to 60% solids, followed by a rapid increase. The 4% tailings exhibited a lower rate and amount of settlement than 5% and 6% tailings. The kidecreased from 10^(-2)to 10^(-4)m/s with a decrease in eifrom 16 to 4 and a decrease in ef from 8 to 4 such that 4% tailings showed one order of magnitude lower values than the 5% and 6%tailings. The settling potential decreased ten times(50%–5%) for 4% tailings and four times(60%–15%)for 5% and 6% tailings. The effective stress increased from 80 to 260 Pa in the settling tests. The 4%tailings were less prone to segregation when compared with 5% and 6% tailings. The average solids content after settling was 35% for 4% tailings, 40% for 5% tailings and 39% for 6% tailings with a solids content deviation of ±3%, ±8%, ±6%, respectively. All materials were essentially non-segregating at 40%initial solids.

关键词： Uranium mill tailings Rheology Settling Segregation

myricetin protects hippocampal CA3 pyramidal neurons and improves learning and memory impairments in rats with Alzheimer's disease

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Neural Regeneration Research 2016年第12期11卷 1976-1980页

作者： matin Ramezani Niloufar Darbandi Fariba Khodagholi azam Hashemi Department of Biology Faculty of ScienceArak University Neuroscience Research Center School of MedicineShahid Beheshti University of Medical Sciences

There is currently no treatment for effectively slowing the progression of Alzheimer＇s disease, so early prevention is very important. Numerous studies have shown that flavonoids can improve memory impairment. The present study investigated the effects of myricetin, a member of the flavonoids, on intracerebroventricular streptozotocin induced neuronal loss and memory impairment in rat models of Alzheimer＇s disease. myricetin at 5 or 10 mg/kg was intraperitoneally injected into rats over 21 days. Control rats were treated with 10 m L/kg saline. Behavioral test（the shuttle box test） was performed on day 22 to examine learning and memory in rats. Immediately after that, hematoxylin-eosin staining was performed to observe the morphological change in hippocampal CA3 pyramidal neurons. myricetin greatly increased the number of hippocampal CA3 pyramidal neurons and improved learning and memory impairments in rats with Alzheimer＇s disease. These findings suggest that myricetin is beneficial for treatment of Alzheimer＇s disease.

关键词： nerve regeneration myricetin Alzheimer's disease streptozotocin hippocampus pyramidal neurons CA3 region behavioral test neural regeneration

Non-invasive diagnosis of H pylori infection: Evaluation of serological tests with and without current infection marker CIm

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World Journal of Gastroenterology 2008年第8期14卷 1231-1236页

作者： Sufi HZ Rahman m Golam azam m Anisur Rahman mS Arfin m mahbub Alam Tareq m Bhuiyan Nasim Ahmed motiur Rahman Shamsun Nahar mS Hassan Department of Immunology Bangladesh Institute of Research and Rehabilitation in Diabetes Endocrine and Metabolic Disorders Dhaka Bangladesh Department of Gastrointestinal Hepatobiliary and Pancreatic Diseases Bangladesh Institute of Research and Rehabilitation in Diabetes Endocrine and Metabolic Disorders Dhaka Bangladesh Department of Pathology Ibrahim MedicalCollege Dhaka Bangladesh Laboratory Sciences Division International Centre for Diarrhoeal Diseases Research Bangladesh Dhaka Bangladesh

AIm:To evaluate the performance of commercially available immunochromatographic (ICT) and immunoblot tests covering the current infection marker CIm and conventional ELISA for the diagnosis of H pylori infection in adult dyspeptic patients. mETHODS:Consecutive non-treated dyspeptic patients undergoing diagnostic endoscopy were tested for H pylori infection by culture, rapid urease test, and histology of gastric biopsy specimens. Serum from 61 H pylori infected and 21 non-infected patients were tested for anti-H pylori IgG antibodies by commercial ELISA (AccuBindTm ELISA, monobind, USA), ICT (Assure H pylori Rapid Test, Genelabs Diagnostics, Singapore), and immunoblot (Helico Blot 2.1, Genelabs Diagnostics, Singapore) assays. ICT and immunoblot kits cover CIm among other parameters and their performance with and without CIm was evaluated separately. RESULTS:Sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and accuracy of ELISA were 96.7%, 42.8%, 83.1%, 81.8%, and 82.9%, of ICT were 90.1%, 80.9%, 93.2%, 73.9%, and 87.8%, of ICT with CIm were 88.5%, 90.4%, 96.4%, 73.0%, and 89.0%, of immunoblot were 98.3%, 80.9%, 93.7%, 94.4%, and 93.9%, and of immunoblot with CIm were 98.3%, 90.4%, 96.7%, 95.0%, and 96.3%, respectively. CONCLUSION:Immunoblot with CIm had the best performance. ICT with CIm was found to be more specific and accurate than the conventional ELISA and may be useful for non-invasive diagnosis of H pylori infection.

关键词： H pylori ELISA Immunochromatographic test Immunoblot Current infection marker