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1.
Tarek Uddin MOHAMMED Aziz Hasan MAHMOOD Mohammad Zunaied-Bin-HARUN Jamil Ahmed JOY Md. Asif AHMED 《Frontiers of Structural and Civil Engineering》2021,15(6):1400-1414
Aggregates are the biggest contributor to concrete volume and are a crucial parameter in dictating its mechanical properties. As such, a detailed experimental investigation was carried out to evaluate the effect of sand-to-aggregate volume ratio (s/a) on the mechanical properties of concrete utilizing both destructive and non-destructive testing (employing UPV (ultrasonic pulse velocity) measurements). For investigation, standard cylindrical concrete samples were made with different s/a (0.36, 0.40, 0.44, 0.48, 0.52, and 0.56), cement content (340 and 450 kg/m3), water-to-cement ratio (0.45 and 0.50), and maximum aggregate size (12 and 19 mm). The effect of these design parameters on the 7, 14, and 28 d compressive strength, tensile strength, elastic modulus, and UPV of concrete were assessed. The careful analysis demonstrates that aggregate proportions and size need to be optimized for formulating mix designs; optimum ratios of s/a were found to be 0.40 and 0.44 for the maximum aggregate size of 12 and 19 mm, respectively, irrespective of the W/C (water-to-cement) and cement content. 相似文献
2.
MARK P. JOY VEDAT TAVSANOGLU 《International Journal of Circuit Theory and Applications》1996,24(1):7-13
In this paper we show that feedback matrices of ring CNNs are block circulants; as special cases, for example, feedback matrices of one-dimensional ring CNNs are circulant matrices. Circulants and their close relations the block circulants possess many pleasant properties which allow one to describe their spectrum completely. After deriving the spectrum of the feedback operator, we discuss conditions for a CNN to be contractive, ensuring global asymptotic stability. 相似文献
3.
INTROGRESSING PHEROMONE QTL BETWEEN SPECIES: TOWARDS AN EVOLUTIONARY UNDERSTANDING OF DIFFERENTIATION IN SEXUAL COMMUNICATION 总被引:2,自引:0,他引:2
Groot AT Ward C Wang J Pokrzywa A O'Brien J Bennett J Kelly J Santangelo RG Schal C Gould F 《Journal of chemical ecology》2004,30(12):2495-2514
As a first step toward understanding how noctuid moths evolve species-specific pheromone communication systems, we hybridized and backcrossed two closely related moth species, Heliothis virescens (Hv) and H. subflexa (Hs), which differ qualitatively and quantitatively in their multi-component sex pheromone blends. We used amplified fragment length polymorphism (AFLP) marker-based mapping of backcross families to determine which of the 30 autosomes in these moths contained quantitative trait loci (QTL) controlling the percentages of specific chemical components in the pheromone blends. In two previous backcrosses to Hs, we found a strong depressive effect of Hv-chromosome 22 on the percentage of three acetate components in the pheromone gland. These acetates are present in Hs and absent in Hv. Here, we describe how we introgressed Hv-chromosome 22 into the genomic background of Hs. Selection for Hv-chromosome 22 started from backcross 3 (BC3) females. All females that had Hv-chromosome 22 and a low percentage of acetates (< 3% of the total amount of pheromone components present) were backcrossed to Hs males. In BC5 to BC8, we determined whether Hv-chromosome 22 was present by a) running only the primer pairs that would yield the markers for that chromosome, and/or b) determining the relative percentages of acetates in the pheromone glands. Either or both genotype and phenotype were used as a criterion to continue to backcross these females to Hs males. In BC9, we confirmed the isolation of Hv-chromosome 22 in the Hs genomic background, and backcrossed the males to Hs females to eliminate the Hv-sex chromosome as well as mitochondrial DNA. The pheromone composition was determined in BC3, BC5, and BC11 females with and without Hv-chromosome 22. All backcross females with Hv-chromosome 22 contained significantly less acetates than females without this chromosome. In addition, BC3 females with Hv-chromosome 22 contained significantly more Z11-16:OH than BC3 females without Hv-chromosome 22. However, in BC5 and BC11 females, the correlation between Z11-16:OH and Hv-chromosome 22 was lost, suggesting that there are separate QTL for the acetates and for Z11-16:OH, and that the relative amount of the alcohol component is only affected in epistasis with other (minor) QTL. Now that we have succeeded in isolating the chromosome that has a major effect on acetate production, we can test in behavioral experiments whether the presence of acetates may have been a driving force for a shift in pheromone composition. Such tests are necessary to move towards an evolutionary understanding of the differentiation in sexual communication in Heliothis spp. moths. 相似文献
4.
SOLAR TUNNEL DRYING OF TURMERIC (CURCUMA LONGA LINN. SYN. C. DOMESTICA VAL.) FOR QUALITY IMPROVEMENT
Turmeric is one of the most ancient medicinal spices of the world. As its homeland, India acts as the largest producer, exporter and consumer of turmeric. The value of turmeric is due to its color and flavor, which is being given by curcumin, volatile oil and oleoresin. The end quality of turmeric is very much dependent on its post-harvest methods. Traditionally, open sun drying is the chief method adopted for processing. In the present investigation, freshly harvested turmeric rhizomes were collected from 30 stations and drying experiments were conducted by adopting three methods: (1) solar tunnel drying; (2) conventional drying; and (3) commercial drying. Various pre-drying and post-drying treatments were conducted. The results proved that conventional processing could maintain the intrinsic quality up to a certain level, but extrinsic quality could not be achieved. Solar tunnel drying method is an effective alternative to traditional open sun drying, where retention of curcumin, volatile oil and oleoresin was high, with less drying time. The study also disclosed the importance of pre-drying and post-drying treatments and hygienic practices to be adopted during processing.
Solar tunnel dryer can be used to process most of the spices, vegetables, fruits and other perishable crops with maximum retention of intrinsic quality and for better shelf life. Substantial reduction of drying time and physical quality improvement with regard to international quality standards are the other advantages. 相似文献
PRACTICAL APPLICATIONS
Solar tunnel dryer can be used to process most of the spices, vegetables, fruits and other perishable crops with maximum retention of intrinsic quality and for better shelf life. Substantial reduction of drying time and physical quality improvement with regard to international quality standards are the other advantages. 相似文献
5.
6.
R.I. SAN MIGUEL M.E. KUNKEL W.C. BRIDGES JR. R.L. DICK J.C. ACTON 《Journal of food science》1990,55(4):885-887
The exchange of 8.4% neutral detergent fiber (NDF) of wheat bran for 8.3% NDF of cellulose in diets containing either beef, chicken, fish or casein as protein sources did not (P>0.05) alter feed consumption, weight gain or energy intake in the protein efficiency ratio (PER) bioassay with weanling rats. Higher (P<0.05) fecal nitrogen (N) excretions and lower (P<0.05) N digestibilities occurred for each protein source when wheat bran was exchanged for cellulose. The exchange also had no effect (P>0.05) on PER or net protein ratio (NPR) of casein or fish protein or on NPR of chicken protein. However, PER and NPR of beef and PER for chicken were reduced (P<0.05) when the dietary fiber was exchanged. 相似文献
7.
The effect of encapsulation, iron and low (LT) or high (HT) temperature drying on thiamin, riboflavin and niacinamide concentrations and on cooked spaghetti parameters of enriched spaghetti were studied. Thiamin, riboflavin and niacinamide were greater in the encapsulated enriched spaghetti. Cooked spaghetti had lower cooked weight but greater firmness when enriched with encapsulated vitamins. Thiamin, niacinamide and cooked weight were greater in cooked spaghetti when iron was added, but spaghetti was less firm. High temperature drying resulted in lower riboflavin and niacinamide in dried spaghetti but did not affect vitamin concentrations in cooked spaghetti. High temperature drying caused less cooking loss and greater firmness in cooked spaghetti. 相似文献
8.
ACCURACY AND ORDER OF REPORT OF 6-DIGIT NUMBER SEQUENCES WERE INVESTIGATED IN 16 UNDERGRADUATES UNDER BOTH FREE-RECALL AND ORDERED-RECALL CONDITIONS. THESE DATA, WHEN COMPARED TO PREVIOUSLY PUBLISHED DATA FOR LETTERS AND FORMS, INDICATE THAT PROCESSING OF NUMBERS IN THE RECOGNITION TASK IS MORE FLEXIBLE THAN THAT OF LETTERS BUT LESS FLEXIBLE THAN THAT OF FORMS. IT IS CONCLUDED THAT WHILE FAMILIARITY PLAYS AN IMPORTANT ROLE, PART OF THE POLARIZATION IN THE PROCESSING OF LETTERS RESULTS FROM UNIQUE PROPERTIES OF LETTERS WHICH REFLECT SS READING EXPERIENCE. (FRENCH SUMMARY) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
9.
摘译电子书市场受众的逐渐增加,极大地促进了人们对低耗、日光下可读反射型显示器的关注。目前的反射显示器通常是黑白的,如亚马逊公司的Kindle电子书使用的是E-Ink Vizplex成像膜;或者仅仅能显示暗淡色域 相似文献
10.
Part orienting tracks used for feeding component parts to an automated assembly system are conventionally designed and fabricated manually by increasingly small numbers of skilled operators. It is time-consuming, labour-intensive and hence results in expensive tooling cost and long manufacture lead time. A new approach based on solid modelling has been developed to facilitate efficient track design and manufacture This paper presents the methodology adopted in the development and implementation of the CAD system. It describes the conceptual model of an orienting track, discusses the overall data structure of the system, and outlines the method used in modelling tracks. The paper concludes with an example demonstrating how an orienting track can be designed using the CAD system. 相似文献