graft copolymerization of 4-vinylpyridine on to celluosics effects of stirring and inorganic salts

the graft copolymerization of 4-vinylpyridine (4-vp) on to unmodified cellulose and partially carboxymethylated cellulose (pcmc) initiated by ceric ammonium nitrate (can) in dilute nitric acid was carried out. the grafting parameters, graft yield (g), total conversion (c//t) and grafting efficiency (ge), were studied as functions of the r..

bidirectional reflectance factors of agricultural targets. a comparison of ground-, aircraft-, and satellite-based observations

the bidirectional reflectance factor (brf) of most natural surfaces exhibits substantial departure from lambertian behavior, yet the magnitude of its effect in off-nadir imagery from the spot satellite remains mostly undocumented. field investigations were conducted at the maricopa agricultural center in arizona to explore this phenomenon..

lidar determination of horizontal and vertical variability in water vapor over cotton

a solar-blind lidar system is being developed for remote noninvasive measurement of atmospheric water vapor concentrations in three dimensions and over time. based on a high-power krf laser operating at 248 nm, the truck-mounted system has 1.5-m resolution of water vapor concentrations along the beam path from 100 m to 500 m from the truc..

polyamide and aromatic polyamide fibers of the 1990s

the development of fiber reinforcement for conveyor belts has progressed from cotton to rayon to the melt spun fibers nylon and polyester and now includes steel and aramid cords. this paper focuses on polyamide fibers, commonly referred to as nylon, and aromatic polyamide fibers, commonly referred to as aramids. it discusses is how these ..

ranking of selected residues for biocoal production. case of thailand

a ranking of ten agricultural and forestry residues was carried out in terms of their suitability for biocoal production. the residues considered were paddy husk, paddy straw, sawdust, sugar cane bagasse, cotton stalk, corn cob, groundnut shell, cassava stalk, coconut husk and coconut shell. ranking was carried out on the basis of annual ..

energy substitution in cotton production in the usa

the paper investigates the nature and extent of the substitution of energy for other inputs in the production of cotton in the usa. the specific inputs considered, in addition to energy, are labour, nitrogen fertilizer, phosphate fertilizer, pesticides and water. the results show that input use is responsive to variations in own prices an..

quantities relevant to the handling safety of greasy wool

greasy wool has a very considerable propensity towards self-heating, and two quantities relevant to such self-heating - activation energy of oxidation and thermal diffusivity - have been measured for four samples of 'as-received' greasy wool. for comparison, the same quantities for two cellulosic fibre materials - raw cotton and kapok - a..

evapotranspiration in sudan gezira irrigation scheme

rapid irrigation development in the sudan has stretched to the limit its share in the nile waters. significant savings on irrigation water can be made by improved water management. accurate estimation of crops evapotranspiration, et, is a prerequisite, et was estimated by predicting first reference crop evapotranspiration. grass was selec..

management model for control of on-farm irrigation

a physically based model for the management and forecasting of irrigation water requirements at an on-farm level is developed. the model includes mechanisms for simulating root and soil-water movement, root growth, and crop yield. model inputs and soil and crop parameters are easily attainable so that the model is usable in field situatio..

economic policies for regulating agricultural drainage water

agricultural drainage water is a major source of environmental pollution in many areas. this paper reviews the literature on the economics of nonpoint-source pollution and applies it to the regulation of agricultural drainage water. four types of regulatory policies are considered. the empirical analysis is carried out for cotton producti..