227 research outputs found

    Producing Load Bearing Block Using LECA as Partial Replacement of Coarse Aggregate

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    The ability to produce load-bearing masonry units adopting ACI 211.1 mix design using (1:3.2:2.5) as (cement: fine aggregate: coarse aggregate) with slump range (25-50mm) which can conform (dimension, absorption, and compressive strength) within IQS 1077/1987 requirements type A was our main goal of the study. The ability to use low cement content (300 kg/m3) to handle our market price products since the most consumption in wall construction for low-cost buildings was encouraging. The use of (10 and 20%) of LECA as partial volume replacement of coarse aggregate to reduce the huge weight of masonry blocks can also be recommended. The types of production of the load-bearing masonry units were A and B for (10 and 20%), respectively. Finally, the use of the spray curing method was the more suitable simulation of reality and easier for factory producers, taking into consideration that the increasing curing time from 14 days (recommended in IQS 1077/1987) to 28 days may be led to conversation masonry type from B to A as in R20%-300.  

    Performance assessment of parabolic trough collector (ptc) by using three passes receiver for preheating the fuel oil under Iraq climate for different mass flow rates

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    An alternative design receiver of parabolic trough collector (PTC) has been discussed in the present study. The three passes design (3p) receiver made from copper and coated with selective black paint was studied and optimized experimentally. Mass flow rates were varied alongside number of days. The proposed design was compared with the PTC equipped with smooth receiver (SM). The aforementioned variations resulted in the experiments performed in September 2018. The 17th, 18th, 19th, and 20th, were chosen for the PTC with smooth receiver, while 25th , 26th, 27th, and 28th were for the receiver with three passes). The solar irradiances for these days were similar. The heat transfer fluid (HTF) was fuel oil. Mass flow rates of 2, 2.5, 3, 3.5 LPM were observed alongside change in number of days for the experiment. The results show that the PTC with three passes receiver achieved higher average thermal efficiency and average useful energy than the PTC with smooth receiver

    Can deficit irrigations be an optimum solution for increasing water productivity under arid conditions? A case study on wheat plants

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    Water scarcity is of growing concern in many countries around the world, especially within the arid and semi-arid zones. Accordingly, rationalizing irrigation water has become an obligation to achieve the sustainable developmental goals of these countries. This may take place via using deficit irrigation which is long thought to be an effective strategy to save and improve water productivity. The current study is a trial to evaluate the pros and cons of using 50 and 75 % of the irrigation requirements (IR) of wheat (deficit irrigations) versus 100 %IR, while precisely charting changes in wheat growth parameters, antioxidant enzymes in plant shoots and the overall nutritional status of plants (NPK contents). Accordingly, a field experiment was conducted for two successive seasons, followed a split-plot design in which deficit irrigations (two irrigations to achieve 50 % of the irrigations requirements (IR), three irrigations to attain 75 % IR, and four irrigations to fulfill 100 % IR) were placed in main plots while four different studied wheat cultivars were in subplots. Results obtained herein indicate that deficit irrigations led to significant reductions in growth parameters and productivity of all wheat cultivars, especially when using 50 % IR. It also decreased NPK contents within plant shoots while elevated their contents of proline, peroxidase, and catalase enzymes. On the other hand, this type of irrigation decreased virtual water content (VWC, the amount of water used in production on ton of wheat grains). Stress tolerance index (STI), and financial revenues per unit area were also assessed. The obtained values of grain productivity, STI, VWC and financial revenues were weighted via PCA analyses, and then introduced in a novel model to estimate the efficiency of deficit irrigations (ODEI) whose results specified that the overall efficiency decreased as follows: 50 %IR < 75 %IR < 100 %IR. In conclusion, deficit irrigation is not deemed appropriate for rationalizing irrigation water while growing wheat on arid soils

    Is spinopelvic sagittal alignment correlated with pain level, functional disability and frontal plane projection angle in women with patellofemoral pain syndrome? A cross-sectional study

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    There is a growing interest concerning the understanding of measurements of spinal and leg alignment in patients with patellofemoral pain syndrome (PFPS). However, evaluating spinopelvic alignment in the sagittal plane with pain level, functional disability and frontal plane projection angle (FPPA) in PFPS has not been adequately addressed. The aim of the study was to identify the correlation of spinopelvic parameters with pain level, functional disability and frontal plane projection angle in women with PFPS. This was a cross–sectional study involving sixty female patients diagnosed with PEPS, with a mean age of 32±6.47. The measurements used in the study included: radiographic parameters (X-Ray), the numeric pain rating scale (NPRS), the Arabic anterior knee pain scale (AAKP/Kujala) and the 2D-FPPA. Spearman correlation analysis was conducted to evaluate the relationship between these parameters. The results of our study demonstrated a strong positive correlation of lumbar lordosis (LL) with pain level and FPPA (r=0.825, r=0.812, p=0.0001). Also, a strong positive correlation of sacral slope (SS) with pain level (r = 0.0.820) and FPPA (r= 0.783). Pelvic tilt (PT) showed a moderate correlation with pain level (r = 0.0.614) and FPPA (r= 0.605), while a weak negative correlation was found between LL, SS and PT and functional disability score (r=-0.397, r=-0.385 and, r=-0.215 p=0.002). It was concluded that LL, SS and PT were significantly related to the pain level, functional disability and frontal plane projection angle in women with PFPS. These spinal alignments should be considered in clinical evaluation of knee-related disorders associated with PFPS

    Frontal-view Face Detection in The Presence of Skin-Tone Regions Using a New Symmetry Approach

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    In this paper, an efficient algorithm for detecting frontalview faces in color images is proposed. The proposed algorithm has a special task; it detects faces in the presence of skin-tone regions such as human body, clothes, and background. Firstly, a pixel based color classifier is applied to segment the skin pixels from background. Next, a hybrid cluster algorithm is applied to partition the skin region. It is well known that the frontal face is symmetrical; therefore we introduce a new symmetry approach, which is the main distinguishing feature of the proposed algorithm. It measures a symmetrical value, searches for the real center of the region, and then removes the extra unsymmetrical skin pixels. The cost functions are adopted to locate the real two eyes of the candidate face region. Finally, a template matching process is preformed between an aligning frontal face model and the candidate face region as a verification step. We have tested our algorithm on 200 images from different sets. Experimental results reveal that our algorithm can perform the detection of faces successfully under wide variations of captured images.Facultad de Informátic

    Extraction and Analysis of Carbamate and Pyrethroid Pesticides in Tomatoes and Rice by Gas Chromatography Mass Spectrometry

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    This work aimed to explore common methods for the extraction of pesticide and to perform qualitative and quantitative analysis by gas chromatography coupled with electron impact mass spectrometry (GC-EI-MS). Extraction was conducted using QuEChERS and Liquid-Liquid (L-L). Calibration curve and standard addition curve were both plotted for different concentration of mixtures. Additionally, the efficiency of the QuEChERS extraction methods was examined by spiking the organic rice and tomato with standard mixture of pyrethroid and carbamate and applying the extraction. Results showed that, in general, carbamate species (especially the aliphatic types) were eluted at earlier times compared to pyrethroids species. Carbamates were more susceptible to degradation during GC separation compared to pyrethroids. A chromatographic resolution of 3.24 was obtained for the two permethrin isomers. Good linearity of the three quantitative methods (R2 > 0.99) were obtained for most compounds. Based on using the standard addition curve, the recovery for the different pyrethroid and carbamate compounds were determined.qscienc

    Waste Animal Bones as Catalysts for Biodiesel Production; A Mini Review

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    Slaughterhouse waste is considered to be an emerging issue because of its disposal cost. As an alternative, it would be a great prospect for the bioeconomy society to explore new usages of these leftover materials. As per food safety rules mentioned by EU legislation, all bone waste generated by slaughterhouses ought to be disposed of by rendering. The huge quantity of worldwide bone waste generation (130 billion kilograms per annum) is an environmental burden if not properly managed. The waste animal bones can be efficiently employed as a heterogeneous catalyst to produce biodiesel. This mini review summarized the recent literature reported for biodiesel generation using waste animal bones derived heterogeneous catalyst. It discusses the sources of bone waste, catalyst preparation methods, particularly calcination and its effects, and important characteristics of bones derived catalyst. It suggests that catalysts extracted from waste animal bones have suitable catalytic activity in transesterification of different oil sources to generate a good quality biodiesel

    Cinnamon and ginger extracts attenuate diabetes-induced inflammatory testicular injury in rats and modulating SIRT1 expression

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    The current study aimed to evaluate the efficacy of simultaneous administration of Zingiber officinale (ginger) and Cinnamomum cassia (cinnamon) extracts in mitigating testicular changes associated with diabetes mellitus in rats and to investigate its molecular mode of action. After induction of diabetes using streptozotocin, 36 male rats were divided to six groups namely control, diabetic, metformin-treated, cinnamon-treated, ginger-treated and combined, each group having 6 rats. Fasting blood glucose, serum insulin, testosterone was measured. Expression of inflammatory mediators; tumor necrosis factor-alpha (TNF-α), Nuclear factor kappa B (NF-κB) and Sirtuin 1 (SIRT1) was assessed in the testicular tissue. Histopathological changes in the testis were observed and spermatogenesis and apoptosis were assessed immunohistochemically. The histological and biochemical studies of the untreated group confirmed structural changes in testes induced by diabetes. Oral administration of ginger and cinnamon increased insulin level significantly increased while the blood glucose level significantly decreased in diabetic rats, improving structural testicular changes considerably. Joint intake of ginger and cinnamon increased antihyperglycemic, antioxidant and anti-inflammatory effects markedly improving the testicular injury compared to the administration of either of them. SIRT1 expression in the testis significantly increased in ginger plus cinnamon-treated rats. These results indicate that when administrated together, ginger and cinnamon synergistically enhanced antioxidant, antiapoptotic and anti-inflammatory effects and induced antihyperglycemic effect comparable to metformin. The combination of ginger and cinnamon also upregulated SIRT1 in the testis

    Modulation Techniques for Biomedical Implanted Devices and Their Challenges

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    Implanted medical devices are very important electronic devices because of their usefulness in monitoring and diagnosis, safety and comfort for patients. Since 1950s, remarkable efforts have been undertaken for the development of bio-medical implanted and wireless telemetry bio-devices. Issues such as design of suitable modulation methods, use of power and monitoring devices, transfer energy from external to internal parts with high efficiency and high data rates and low power consumption all play an important role in the development of implantable devices. This paper provides a comprehensive survey on various modulation and demodulation techniques such as amplitude shift keying (ASK), frequency shift keying (FSK) and phase shift keying (PSK) of the existing wireless implanted devices. The details of specifications, including carrier frequency, CMOS size, data rate, power consumption and supply, chip area and application of the various modulation schemes of the implanted devices are investigated and summarized in the tables along with the corresponding key references. Current challenges and problems of the typical modulation applications of these technologies are illustrated with a brief suggestions and discussion for the progress of implanted device research in the future. It is observed that the prime requisites for the good quality of the implanted devices and their reliability are the energy transformation, data rate, CMOS size, power consumption and operation frequency. This review will hopefully lead to increasing efforts towards the development of low powered, high efficient, high data rate and reliable implanted devices
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