Improving the impact resistance of p-aramid fabrics by sequential impregnation with shear thickening fluid

A simple and effective method for impregnation of p-aramid (Kevlar^®) fabric with shear thickening fluid (STF) has been developed in this research. Kevlar fabric was impregnated with STF in two stages in a sequential manner. Three levels of pressure (0.5, 1 and 2 bar) were used in each stage of impregnation. It was observed that impact energy absorption by Kevlar fabrics, impregnated with STF in this newly developed method, increased significantly as compared to untreated Kevlar fabrics and Kevlar fabrics treated with STF in conventional way (single step impregnation). Better results were obtained when the first impregnation pressure was higher than that of the second, even with same combination of pressures. Such fabrics also showed a much higher STF add-on (~18 %) as compared to that of fabrics impregnated in single step (3-5 %). Low velocity ballistic tests also confirmed the advantages of the new method as sequentially impregnated fabric showed 124.8 % and 24.4 % increase in impact energy absorption compared to untreated and STF impregnated Kevlar fabrics in single step, respectively.     

Study on soils under shifting cultivation and other land use categories in Chittagong Hill Tracts, Bangladesh

Soil samples were collected and analyzed from 25 sites of three hilly regions (Rangamati, Banderban and Khagrachari) for an understanding of the impact of denudation and land use on soils in Chittagong Hill Tracts, Bangladesh. There were natural forests, bushy land, slashed sites, slashed and burnt sites, and the sites prepared for shifting cultivation, one year after shifting cultivation and two years after shifting cultivation. The soils were generally yellowish brown to reddish brown, sandy to sandy clay loam, strongly acid, and well to excessively drained on steep slopes with considerable variation among the sites and land use categories. Bulk density was the highest in sites of one year after shifting cultivation (1.52 g·cm-3) and the lowest in forested sites (1.38 g·cm-3). Water holding capacities were, however, statistically similar in all sites. Organic carbon varied from 0.54% (slashed and burnt sites) to 1.55% (forested sites) and total N ranged from 0.05% (shifting cultivation for one year) to 0.13% (forested sites). Available phosphorus (Bray & Kurtz-2 P) was the maximum in forested sites (12.32 mg·kg-1), and it did not differ significantly in other sites. Contents of available Ca, Mg and K were also higher in the bushy lands and forested sites than cleared and shifting cultivated sites.     

Co-Composting Urban Waste,Plant Residues,and Rock Phosphate: Biochemical Characterization and Evaluation of Compost Maturity

Co-composting of urban wastes (UWs) and plant residues with rock phosphate (RP) produces quality compost and reduces the use of chemical phosphorus fertilizer. Biochemical process of three compost piles (P): P₁- 50% UW + 30% rice straw (RS) + 10% sawdust (SD) + 8% RP + 2% sugarcane trash (ST), P₂- 50% UW + 23% RS + 10% SD + 15% mustard oil cake + 2% ST, and P₃- 95% UW + 5% RP was studied. Decomposition rate followed first-order kinetics and maximum (77%) was in P₃. The highest bacterial population was found in P₂ having higher cumulative CO₂ evolution (53.76 mg CO₂ g^?1 volume solid). Prevalence of phosphate-solubilizing bacteria was 2.0 to 6.3 Log₁₀ Cfu g^?1 dry weight and concentrated in RP-amended piles. Humic acid of compost was classified as rotteprudukte. Final pH (7.5 to 8.0) and germination index (>90) proved that the compost was mature. P₃ compost (1 t ha^?1, fresh weight) had potential to supply 25 kg phosphorus.     

Antidiarrhoeal activity of Strychnos potatorum seed extract in rats

The antidiarrhoeal activity of the methanol extract of the dried seeds of Strychnos potatorum (MESP) has been evaluated out in rats using different models (castor oil-induced diarrhoea, effects on gastrointestinal motility and on PGE(2)-induced gastric enteropooling. MESP (100, 200 and 400 mg/kg, p.o.) significantly (P<0.001) inhibited the frequency of defaecation and reduced the wetness of faecal droppings in castor oil-induced diarrhoea, decreased the propulsion of charcoal meal through the gastrointestinal tract, and also reduced the PGE(2)-induced enteropooling.     

Cercoseptoria needle blight of pines in nurseries: disease spread and control strategies

Studies on the epidemiology of Coroseptoria needle blight of Pinus roxburgbii are presented. Disease spread is related to high rainfall. An integrared approach for control of the disease is given.     

孟加拉国丘陵地带桔园和灌木林地土壤物理性质的比较评价(英文)

对孟加拉国丘陵地带Mro部落经营的桔园与灌木林35%和55%两种坡地土壤物理性质进行了比较与评价。每一块用地内挖掘3个土壤剖面采集不同深度(0-5cm,5-15cm and 15-30cm)的土壤样品,测定土壤水分、有机质含量和土壤密度。最大持水量、田间持水量、干或湿土壤容重和土壤孔隙度的测定仅限于表层土壤。两种坡地桔园3个深度的土壤水分含量均显著高于灌木林地相同深度的土壤水分。桔园在55%坡地内土壤有机质含量低于林地含量值,而在35%坡地内的含量值则高于林地值。两块样地内上述两项测定值均在表层土壤中最高,且随土层深度的增加而降低。与灌木林地比较,桔园地表层土壤最大持水量、孔隙度和3个不同深度的土壤密度均较低。两块用地内不同坡地的表层土田间持水量有所差异,且桔园地干或湿表层土壤容重高于林地内的数值。表5参23。     

Yield and water use efficiency of cauliflower under varying irrigation frequencies and water application methods in Lower Gangetic Plain of India

A field study (1999-2000 to 2001-2002) was carried out to optimize the irrigation frequency and suitable water application methods for cauliflower with a view to increase curd yield (CY) and water use efficiency (WUE). Check Basin (CB), Each Furrow (EF) and Alternate Furrow (AF) methods were tested with three irrigation frequencies depending on the attainment of soil matric potential (Ψ_m) value at 0.2 m depth as: −0.03 MPa (F₁), −0.05 MPa (F₂) and −0.07 MPa (F₃). Maximum CY was recorded under F₁ and decreased by 10.4 and 31.4%, respectively under F₂ and F₃ frequencies. In contrast, WUE decreased by 9.3% from F₃ to F₁. Highest CY and WUE obtained under CB followed by EF and AF methods. Furrow application methods saved 12-24% irrigation water over CB method. Maximum soil water stress coefficient (K_s) recorded at curd development stage in comparison to other stages. Both seasonal evapotranspiration (ET_a) and yield-moisture stress index (Kys) recorded positive linear relationships with CY. Present study shows a crop response factor of 0.822 for cauliflower. In this region, cauliflower should be irrigated with check basin method at an interval of 8-10 days.     

Sulfur accumulation in Vertisols due to continuous gypsum application for six years and its effect on yield and biochemical constituents of soybean (Glycine Max L. Merrill)

Application of S through inorganic sources is recommended to the crops in the cropping system in S deficient soils of India. However, transformations of S in the soil profile following continuous gypsum application are not known. The accumulation of S into different fractions due to application of a total of 180—540 kg S ha^—1 over a six‐year‐period in soybean — wheat cropping system and its effect on the yield and quality of soybean produce were investigated in a vertisol area. About 25—38% of the S added was retained in the 90 cm depth of profile. Significant changes in the total S content in soil layers were recorded wherein a total of 360 kg S ha^—1 or more S was applied. Maximum increase in total S content was recorded in upper layers. Soluble S accumulated more in the 30—75 cm depth; whereas, proportion of sorbed fraction of S increased with depth. Build up of S in the surface layer of the profile was mostly related to the increase in organic fraction. The S accumulation in lower layers of the profile was mostly due to increase in soluble and sorbed fractions of S. Such an increase of the S content in the soil caused an increase in seed yield, uptake of S as well as content of oil and S containing amino acids, cystine, and methionine in seed of soybean crop.     

Influence of farmyard manure, inorganic fertilizers and weed control practices on some soil physical properties in a long-term experiment

Abstract. In a long-term experiment, soil physical properties were studied after 20 annual cycles of maize-wheat-fodder cowpea cropping with annual application of inorganic fertilizers and farmyard manure (FYM). Weeds were controlled by hand or by the use of herbicides. The hand weeding treatment resulted in a lowering of the bulk density of the surface layer (0-15 cm) and a significant increase in the subsurface (15–30 cm) density. Application of FYM significantly increased the soil organic carbon (OC), infiltration rate, water retention, aggregation and aggregate stability in water. Application of inorganic fertilizers had small but statistically significant effect in increasing soil OC.     

Influence of cell volume changes on protein synthesis in isolated hepatocytes of air-breathing walking catfish (<Emphasis Type="Italic">Clarias batrachus</Emphasis>)

The present study aimed at determining the effect of cell volume changes on protein synthesis, measured as the incorporation of [³H]leucine into acid-precipitable protein, in isolated hepatocytes of air-breathing walking catfish (Clarias batrachus). The rate of protein synthesis, which was recorded to be 10.02 ± 0.10 (n = 25) nmoles mg⁻¹ cell protein h⁻¹ in isotonic incubation conditions, increased/decreased significantly by 18 and 48%, respectively, following hypo- (−80 mOsmol l⁻¹)/hypertonic (+80 mOsmol l⁻¹) incubation conditions (adjusted with NaCl), with an accompanying increase/decrease of hepatic cell volume by 12 and 20%, respectively. Similar cell volume-sensitive changes of protein synthesis were also observed when the anisotonicity of incubation medium was adjusted with mannitol. Increase of hepatic cell volume by 9%, due to addition of glutamine plus glycine (5 mM each) to the isotonic control incubation medium, led to a significant increase of protein synthesis by 14%. Decrease of hepatic cell volume by 15 and 18%, due to addition of dibutyl-cAMP and adenosine in isotonic control incubation medium, led to a significant decrease of protein synthesis by 30 and 34%, respectively. Thus, it appears that the increase/decrease of hepatic cell volume, caused either by changing the extracellular osmolarity or by the presence of amino acids or certain other metabolites, leads to increase/decrease of protein synthesis, respectively, and shows a direct correction (r = 0.99) between the hepatic cell volume and protein synthesis in walking catfish. These cell volume-sensitive changes of protein synthesis probably help this walking catfish in fine tuning the different metabolic pathways for better adaptation during cell volume changes and also to avoid the adverse affects of osmotic stress. This is the first report of cell volume-sensitive changes of protein synthesis in hepatic cells of any teleosts.