improving the processing and the recycled paper properties is one of permanent concern of papermaking. in this research, the effect of nanochitosan addition on the process and product quality made of writing and printing recycled fiber was investigated. being nano size and so its capability in access to the space between pulp suspension components and also its probable ability to make electrost...

organochlorine pesticides are as environmental pollutants which have a high half-life and transmit from food chain to human and cause side effects such as mutations in different genes and finally cancer. in this research, after sampling and quantitative and qualitative of organochlorine residue, biodegradation of alpha, beta and gamma hexachlorobenzene (linden), ddt, aldrin, dieldrin, endosulfa...

background and purpose     methods:     results     conclusion:

abstract this study was conducted to evaluate the resistance of 70 genotypes of barley to powdery mildew. after preparing the samples contaminated with powdery mildew, reproduction of the spores of the fungus was conducted on susceptible cultivar afzal. the experiment was conducted with randomized block design in pot in greenhouse. seedlings were inoculated with the spores fungus in two-leaf st...

in this study, precipitated calcium carbonate (pcc) was modified using cationic starch, and its effect on optical and physical properties of paper was examined in comparison with unmodified filler afterwards. to determine the filler retention in paper, both modified and unmodified fillers were added to pulp suspensions by 20, 30, and 40 percentages. for comparing the utilization effect of modif...

the present study was carried out to determine the effects of supplementing chromium-methionine(cr-met) on performance and carcass traits in mahabadi goat kids. thirty-two male kids (averageinitial bw of 22 ± 2 kg, 4-5mo) were used in a completely randomized design of four treatments vis.:1) control (with no cr suppl.), 2) 500ug cr suppl., 3) 1000ug cr suppl.and 4) 1500ug cr suppl.as cr-met/ani...

sizing of paperboard has a distinctive position in packaging grade paperboard material. optimization of sizing by alum-rosin at neutral ph in 4 layered paperboard (330 g/m2) wereevaluated in this study to find the optimum ratio of alum- rosin loading in the process. fixed amount of 1% cationic dispersed rosin together with alum as a fixing agent at 5 different levels of 1, 1.5, 2, 3, and 4% (ba...

abstractbackground and objectives: black mustard (brassica nigra (l.) koch) is an annual plant belongs brassicaceae. it has a variety of uses in traditional medicine for rheumatic and neurological pain. growth and development and production of medicinal plants, like other plants is influenced by genetic and environmental factors. select the most appropriate planting date and the most favorable ...

this research was conducted to study the effects of styrene and methyl methacrylate cell lumen monomers on the mechanical properties and decay resistance of beech wood. mechanical and decay resistance test samples were prepared according to astm d143-94 and din en113 standards and impregnated with five concentration monomer solution 0, 40, 60, 80 and 100 percent using bethell method. treated sa...

introduction earth has ever been exposed to environmental hazards. the hazards are continually occurring in the world in the recent years. among them, atmospheric elements have created many human and financial losses in different regions. one of the hazards is dust events and in its severe case is dust storm. it happens more frequently in arid and semiarid regions in deserts and their surroundi...