检索结果-南通市图书馆

Thickness, Distribution and Quality Assessment of Gopalganj-Madaripur Peat Deposits: A Case Study of Potential Economic Opportunities in Mid-Eastern Low-Lying Bangladesh

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

International Journal of Geosciences 2014年第9期5卷 943-955页

作者： Mrinmoy Kumar Maitra md. Ashraful Islam md. al mamun Department of Geological Sciences University of Canterbury Christchurch New Zealand Department of Geology University of Dhaka Dhaka Bangladesh Padma Mining & Energy Corporation Limited Dhaka Bangladesh

The present research work illustrates the extent, distribution and a generalized quality assessment of southern low-lying peat deposits in Madaripur and part of Gopalganj district that covers approximately 17,000 hectare areas. Based on the survey of 800 boreholes, drilled in this region at different times by several government and non-government organizations for the purposes of peat exploration and hydrogeological investigation, reveals that the study area is composed of a considerable amount of peat deposits in various localities among which the deposits at Baghia-Chanda beel in Madaripur and Gopalganj districts are the most remarkable. The average peat thickness (in-situ condition), studied during field investigation, is 6.5 feet for the upper peat deposits, overlying with an average of 3.5 feet of alluvium cover, followed by the lower peat layer of about 3 feet thick that begins at an average depth of 8 feet and separated by a thin bluish grey silty clay sediments from the upper one. The lower part of the study area, locally known as beels, is the most prospective region for peat, whereas the western part is less potential either having no peat intersection or minimal peat thickness. The overburden covers, on the other hand are inversely correlated with the peat thicknesses, i.e., thick overburden tend to correlate with thin peat deposits and the thickest peat intersections have no or minimal overburden. Due to the variation in bulk density and peat depth, this Holocene peat has an average of 59.10% carbon stock. Nitrogen levels, more than 3%, indicate that the peat developed from the decomposition of reeds, sedges, bushes and trunks of trees (higher in nitrogen) rather than either moss or grass (lower in nitrogen). Higher sulphur content (about 2.7%) reflected the influence of brackish environments where the formation of FeS2 took place in the roots of existing vegetation. The calorific values, about 1308.8 k-cal/kg (after 20% moisture reduction), suggest that

关键词： Bengal Basin Depression Incipient Peat Proximate Analysis

A Survey on Matching of Shoeprint with Reference Footwear in Forensic Study

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Computer and Communications 2019年第9期7卷 19-26页

作者： md. al mamun Morium Akter Mohammad Shorif Uddin Department of Computer Science and Engineering Jahangirnagar University Savar Bangladesh

Footwear impression marks on the outside surface of shoes are distinctive patterns and an important forensic clue often found at offense scenes. However, in many cases, the footwear mark is treated with improper evidence due to difficulties in visibility and understanding. This paper presents a thorough review of matching algorithms along with enhancement techniques of shoeprint in the forensic study. Finally, it shows some research directions.

关键词： Forensic Study Footwear Shoeprint Feature Extraction Segmentation

Backward Support Computation Method for Positive and Negative Frequent Itemset Mining

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Data Analysis and Information Processing 2023年第1期11卷 37-48页

作者： Mrinmoy Biswas Akash Indrani Mandal md. Selim al mamun Department of Computer Science and Engineering Jatiya Kabi Kazi Nazrul Islam University Mymensingh Bangladesh

Association rules mining is a major data mining field that leads to discovery of associations and correlations among items in today’s big data environment. The conventional association rule mining focuses mainly on positive itemsets generated from frequently occurring itemsets (PFIS). However, there has been a significant study focused on infrequent itemsets with utilization of negative association rules to mine interesting frequent itemsets (NFIS) from transactions. In this work, we propose an efficient backward calculating negative frequent itemset algorithm namely EBC-NFIS for computing backward supports that can extract both positive and negative frequent itemsets synchronously from dataset. EBC-NFIS algorithm is based on popular e-NFIS algorithm that computes supports of negative itemsets from the supports of positive itemsets. The proposed algorithm makes use of previously computed supports from memory to minimize the computation time. In addition, association rules, i.e. positive and negative association rules (PNARs) are generated from discovered frequent itemsets using EBC-NFIS algorithm. The efficiency of the proposed algorithm is verified by several experiments and comparing results with e-NFIS algorithm. The experimental results confirm that the proposed algorithm successfully discovers NFIS and PNARs and runs significantly faster than conventional e-NFIS algorithm.

关键词： Data Mining Positive Frequent Itemset Negative Frequent Itemset Association Rule Backward Support

Effect of Seeding Density on Mat-Type Seedling Quality for Mechanical Transplanting in Dry Season Rice

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Agricultural Sciences 2021年第11期12卷 1231-1243页

作者： Nilufar Yasmin Shaikh md. Ashraful alam Mohammad Kamruzzaman md. Abdullah al mamun AKM Saiful Islam Biotechnology Division Bangladesh Rice Research Institute (BRRI) Gazipur Bangladesh Farm Machinery and Post-Harvest Technology Division Bangladesh Rice Research Institute (BRRI) Gazipur Bangladesh Agricultural Statistics Division Bangladesh Rice Research Institute (BRRI) Gazipur Bangladesh

Rice transplanting with a transplanter is a cost-effective process. Due to labor shortages during the peak time of rice transplanting, it is a promising technology in Bangladesh. However, the high-quality mat-type seedling is a prerequisite factor for mechanical transplanting. The experiments were conducted at three different locations (Gazipur, Tangail, and Rangpur) during the dry season (Boro)/2019-20 to determine the best seeding density for high-quality mat-type seedlings to be prepared for mechanical rice transplanters. The effects of seeding rate on seedling quality such as survival rate, seedling strength, stem thickness of newly released boro rice varieties BRRI dhan86, BRRI dhan89, and BRRI dhan92 were studied using four seeding rates (130, 140, 150, 160 g/tray). Results revealed that BRRI dhan92 showed quick seedling emergence compared to BRRI dhan89 and BRRI dhan86. Seedling mortality was found the lowest BRRI dhan92 while the highest in BRRI dhan86. 25 - 30 days old seedling was found suitable for mechanical transplanting in terms of seedling mortality. Seedling height increased with the increase in seed density. BRRI dhan92 showed the highest stem thickness followed by BRRI dhan89 and BRRI dhan86 with seed rate 150 - 160 g per tray. The suitable seeding rate (150 - 160 g/tray) for the studied varieties was found better for raising mat-type seedlings suitable for mechanical transplanting, which could coordinate the production of larger population growth and higher harvest index to achieve high grain yield.

关键词： Rice Seed Density Mortality Seedling Age Stem Thickness Seedling Strength

Effect of Planting Methods on the Yield and Yield Attributes of Short Duration AmanRice

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

American Journal of Plant Sciences 2014年第3期5卷 251-255页

作者： md. Masud Rana md. Abdullah al mamun Afruz Zahan md. Nayeem Ahmed md. Abdul Jalil Mridha Adaptive Research Division Bangladesh Rice Research Institute Gazipur Bangladesh Agronomy Division Bangladesh Rice Research Institute Gazipur Bangladesh Soil Science Division Bangladesh Rice Research Institute Gazipur Bangladesh

To find out the effect of planting methods on the yield and yield attributes of short duration Aman rice varieties, a field trial was conducted at the farm of Bangladesh Rice Research Institute, Gazipur, during July to November 2012. The treatments comprised of three BRRI released high yielding varieties viz., BRRI dhan39, BRRI dhan49 and BRRI dhan57 and three planting methods viz., direct seeding of dry seed, direct seeding of sprouted seed and transplanting. It was a factorial experiment conducted in a Randomized Complete Block Design with three replications. Planting methods had a significant effect on the growth duration of rice. The rice crop established with direct seeding of the dry and sprouted seed matured 7 days earlier than transplanting. The variety BRRI dhan39 gave the highest yield (4.964 t·ha-1) when grown with direct seeding of sprouted seed compared to other varieties. The highest net return (23362.00 BDT ha-1) and cost benefit ratio (1:1.49) were observed in direct seeding of the sprouted seed method. So, direct seeding of sprouted seed might be the best planting method because about 19.94% production cost is reduced due to the omission of seedling raising and transplanting operations as well as the reduction in the length of the crop cultivation period.

关键词： Direct Seeding of Dry and Sprouted Seed Growth Duration Short Duration Aman Rice

Dyeing of S/J Cotton Knit Fabric with Natural Dye Extracts from Green Walnut Shells: Assessment of Mordanting Effect on Fastness Properties

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Textile Science and Technology 2017年第2期3卷 17-30页

作者： Zakaria md. Eanamul Haque Nizam md. Hasan al mamun md. Abu Yousuf Ramjan ali Lutfor Rahman md. Raza Miah School of Chemistry and Chemical Engineering Wuhan Textile University Wuhan China School of Fashion Design and Engineering Wuhan Textile University Wuhan China School of Textile Science and Engineering Wuhan Textile University Wuhan China Department of Textile Engineering City University Dhaka Bangladesh

In this study, aqueous extraction method is used because of its high extraction ratio, light fastness and also functional properties. In 1st phase, for dyeing S/J cotton knit fabric with green walnut power ferrous sulfate is considered as a mordant. In this study, three different mordanting methods such as pre-, meta-, and post-mordanting are conveyed the dyeing process with the state of metallic mordant and without metallic salt mordants. In 2nd phase, in dyeing for fixation ferrous sulfate was considered as mordants. Furthermore, the analysis and evaluation of each colour dyed material was done through following two terms for instance CIELAB (L*, a*, and b*) and K/S values. According to AATCC test methods, colour fastness to washing, crocking, perspiration of the dyed samples is determined whereas according to the ISO standard, the colour fastness to light was estimated and tested. When dyeing was carried out on S/J cotton knit fabric through considering optimum parameter like at 80°C for 60 min and at pH 4 which showed optimum results. From the results we can see, very good wash fastness was obtained while there is no fading of the colour, whereas the outstanding and moderate level of colour fastness to light and crocking is achieved.

关键词： Green Walnut Shell Dye Extraction S/J Cotton Knit Fabric Colour Strength Fastness

Synthesis, Structural and Physical Properties of Cu1–xZnxFe2O4Ferrites

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Materials Sciences and Applications 2011年第11期2卷 1675-1681页

作者： Shahida Akhter Deba Prasad Paul md. Abdul Hakim Dilip Kumar Saha md. al-mamun alhamra Parveen 不详

Zn substituted Cu-Zn ferrites with a composition Cu1-xZnxFe2O4 have been synthesized by standard double sintering ceramic method and characterized by X-ray diffraction. The single-phase cubic spinel structure of all the samples has been confirmed from X-ray diffraction analyses. The lattice constant is found to increase linearly with the manganese content obeying Vegard’s law. This increase in lattice parameter is explained in terms of the sizes of component ions. It is well known that density plays a key role in controlling the properties of polycrystalline ferrites. The X-ray and bulk densities of the Cu-Zn ferrite is significantly decreased whereas porosity increased with increasing Zn concentration, thereby giving an impression that zinc might be helping in the densification of the materials. SEM micrographs exhibit a decrease in grain size with increasing Zn content. The real part of initial permeability, μ′ increase with increasing Zn contents upto x = 0.5 after that it decreases with higher Zn content.

关键词： Ferrites XRD Lattice Parameter Density Porosity Permeability

Effect of Field Treatment on Microfloral Respiration and Storability of Canola under Different Storage Conditions

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

American Journal of Plant Sciences 2019年第11期10卷 1989-2001页

作者： Fuji Jian Peian Tang md. Abdullah al mamun Digvir S. Jayas Department of Biosystems Engineering University of Manitoba Winnipeg Canada College of Food Science and Engineering Nanjing University of Finance and Economics Nanjing China

Whether different field treatments such as straight cut, swathing, or pre-harvest aid application can influence the canola storage is the critical information for growers. The effect of these different field treatments on the infection and development of microflora on canola seeds with 9%, 11%, and 14% moisture content at 20°C, 25°C, 30°C and 35°C was determined. To evaluate the microfloral infection and development, concentration of CO2 and O2 in 150 g canola bulks were measured every 3 d. At the beginning and end of the study (66 d), the seed moisture content, germination, visible mold, invisible fungal infection, and yellow seed count were measured. The swathed and nature ripened canola had a slightly higher respiration rate at ≥30°C and ≥ 2 wk than the seeds with other field treatments. The swathed canola had a marginally lower initial germination and higher germination at 66 d. The Glyphosate treated and nature ripened canola seeds had a slightly higher chance of visible model development. However, all these differences were not significant at α = 0.05 level and different field treatments and storage conditions did not influence the yellow seed count.

关键词： Canola Pre-Harvest Treatment Pre-Harvest Aid Respiration Safe Storage

The Effect of La on the Physical and Magnetic Properties of NiCuZn Ferrites

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

材料科学与工程（中英文B版） 2011年第7期1卷 891-894页

作者： Saiduzzaman md. Abul Hossain A.K.M. Hakim Saroaut Noor Robiul Islam md. al-mamun Department of Physics Jahangirnagar University Dhaka Bangladesh Materials Science Division Atomic Energy Centre Dhaka Bangladesh Department of Physics KUET Khulna Bangladesh

Lanthanum-substituted NiCuZn ferrites Ni0.26Cu0.16Zn0.58LaxFe2-xO4 were prepared by usual ceramic method. The samples were investigated for their structural properties such as lattice parameter and density as a function of La content. The lattice parameter of the samples increased with the increasing of La which might be attributed to the larger ionic radius of La3+. The density slightly increased with the increasing of La content. The Scanning Electron Microscope (SEM) micrographs of the samples were observed to investigate grain sizes. It was also observed that bulk density was less than X-ray density. The electrical and magnetic properties such as resistivity, initial permeability, Curie temperature as a function of temperature, frequency and La content were also studied. The initial permeability at 100 kilohertz was found to increase at a certain limit and then decrease with the increasing of La content. The magnetic hysteresis loops of the samples were measured at room temperature.

关键词： NiCuZn铁氧体磁学性质扫描电子显微镜物理射线密度镧晶格参数居里温度