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121.
G.?M.?Shafiur Rahman Hrithita?Aftab M.?Shariful IslamEmail author Muhammad?Zobayer?Bin?Mukhlish Farhad?Ali 《Fibers and Polymers》2016,17(1):59-65
Bio-based CaCO3 powder was synthesized via size reduction method from waste eggshells. The XRD analysis revealed that eggshell powder consists of CaCO3 in calcite form. The inclusion level of CaCO3 contents were varied of 5, 10, 15, 20 and 25 wt.% of prepared CaCO3-polyester film. Effects of different proportions of prepared chicken eggshell and commercial CaCO3 filler on the polyester resin composites films were compared by means of mechanical and physical test. It was found that the addition of CaCO3 filler to the polyester films leads to improve the mechanical properties. The findings revealed that the best and optimum CaCO3 filler content was 10 wt.% and among the prepared polyester films, eggshell CaCO3-polyester films showed the best performance. The mechanical properties of CaCO3-polyester films were measured in terms of tensile strength, elongation-at-break, tensile modulus, flexural strength and impact strength. For eggshell CaCO3- polyester films, the maximum values of the aforementioned mechanical properties were 52.70 MPa, 4.63 %, 1868.70 MPa, 101.20 MPa and 8.40 kJ/m2, respectively, whereas for commercial CaCO3-polyester films those values were 48.12 MPa, 4.50 %, 1790.30 MPa, 97.50 MPa and 8.21 kJ/m2, respectively. Further, water absorption of the composite films as a function of time had also been investigated at 10 wt.% filler content. 相似文献
122.
Atiqur Rahman Barbhuiya Ayyanadar Arunachalam Prabhat Chandra Nath Mohammed Latif Khan Kusum Arunachalam 《Journal of Forest Research》2008,13(1):25-34
Rates of weight loss and nutrient (N and P) release patterns were studied in the leaf litter of the dominant tree species
(Ailanthus grandis, Altingia excelsa, Castanopsis indica, Duabanga sonneriatioides, Dysoxylum binectariferum, Mesua ferrea,
Shorea assamica, Taluma hodgsonii, Terminalia myriocarpa and Vatica lancefolia) of a tropical wet evergreen forest of northeast India. Nitrogen and phosphorus mineralization rate and decay pattern varied
significantly from species to species. In general, the decay pattern, characterized by using a composite polynomial regression
equation, exhibited three distinct phases of decay during litter decomposition—an initial slow decay phase (0.063% weight
loss day−1), followed by a rapid decay phase (0.494% weight loss day−1) and a final slow decay phase (0.136% weight loss day−1). The initial chemical composition of the litter affected decomposition rates and patterns. Species like D. sonneriatoides, D. binectariferum, and T. hodgsonii with higher N and P content, lower carbon and lignin content, and lower C:N ratio and lignin:N ratio exhibited relatively
faster decomposition rates than the other species, for example M. ferrea, C. indica and A. grandis. A slow decay rate was recorded for species such as M. ferrea, C. indica, and A. grandis. The initial N and P content of litter showed significant positive correlations with decay rates. Carbon and lignin content,
lignin:N, and C:N showed significant negative correlations with decay rates. Soil total N and P, and rainfall, soil temperature,
and soil moisture had positive correlations with decay rates. The rapid decomposition rates observed in comparison with other
different forest litter decay rates confirm that tropical wet evergreen forest species are characterized by faster decomposition
rates, indicating a faster rate of organic matter turnover and rapid nutrient cycling. 相似文献
123.
The ethanol extract of leaves of Derris uliginosa given by oral route at dose of 250 and 500 mg/kg produced a significant inhibition on acetic acid-induced writhing in mice. 相似文献
124.
Inheritance of yield and yield contributing characters were investigated using generation mean analysis, utilising the means
of six basic populations viz., P1, P2, F1, F2, BC1P1 and BC1P2 in four crosses of Vigna sesquipedalis. The analysis reiterated that the importance of dominance (h) gene effects for pod yield/plant and pods/plant as compared
to additive (d) gene effects. However, significant and positive additive effects were noticed for pod yield/plant, pods/plant,
pod weight and seed weight in different crosses. The three types of gene interactions (additive, dominance and epistasis)
were significantly involved for pods/plant in cross KU 7 ×KU 8. Among the digenic epistatic interactions, both additive ×additive
(i) and dominance × dominance (l) contributed more for pod yield/plant and pods/plant, however, it varied among the crosses.
Populations having earliness can be developed as indicated by reducing dominance effects. Pedigree selection and heterosis
breeding is suggested to exploit the fixable and non fixable components of variation respectively in Vigna sesquipedalis.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
125.
The structural diversity of different tree-crop associations were studied at Gachabari Sal forest area of Madhupur Garh on Buffer and Peripheral Zone during 2006. The total density, basal area of trees in the Buffer and Peripheral Zone were 155.5 trees·hm^-2, 795.4 trees·hm^-2 and 3.9 m^2·hm^-2, 5.8 m^2·hm^-2, respectively. No regeneration and natural trees were found in Peripheral Zone and the Zone is totally occupied by exotic species where the Buffer Zone comprised of both natural and exotic trees. The Peripheral Zone belonged to younger and smaller trees whereas the Buffer Zone belonged to mixture of smaller, taller, younger and mature trees simultaneously. For the practicing of different agroforestry systems both Zones have lost their original characters of Sal forest. 相似文献
126.
对孟加拉国4个苗圃(IFES、IFESCU、BFRI和ANC)内水黄皮叶斑病症状和严重性进行了调查,结果表明:IFESCU苗圃内叶斑病侵染率及致病指标最高、BFRI次之、ANC最低.与叶斑病相关联的组织从发病植株分离出来,被分离的真菌形成致病性.结果证实胶孢炭疽菌即为致病菌.观察了杧果炭疽病菌丝体生长抑制性并对杀菌剂(Bavistin, Cupravite and Dithane M-45) 有效性和浓度(0.05, 0.10, 0.50, 1.00, 1.50 和 2.00%)进行了鉴定.0.05% Bavistin和Cupravite潜伏8天后,菌丝体生长分别处于最低和最高水平.结果表明:Bavistin杀菌效果最好、Diathane M-45次之,Cupravite对菌丝体生长的抑制作用最低.图1表4参27. 相似文献
127.
128.
M H Rahman 《Folia parasitologica》1984,31(1):63-67
Studies of the effects of host-immunity on the life cycle of Hyalomma rufipes were carried out by allowing the ticks to feed on New Zealand white rabbits under laboratory conditions. The immunity of the rabbit host significantly affected the life cycle of this tick, reducing the percentage recovery of engorged females, their engorged weights and the total number of eggs laid by these females. The viability of the eggs laid by them was also considerably reduced compared to the eggs laid by females fed on naive rabbit hosts. The effects of host immunity were also revealed in the tendency towards three-host development of this species, which otherwise behaved as a two-host tick when fed on non-immune rabbit hosts. 相似文献
129.
130.