Air pollution in Beijing-Tianjin-Hebei region has caused widespread concern. In winter, the combustion of fossil fuel produces a very high proportion fine particulate matter air. However, vegetation coverage is relatively low. The dust retention evergreen plants particularly important for improving air quality. this study, five species were selected, and effects leaf stomatal characteristics (s...

the aim of study was to evaluate qualitative and quantitative characteristics of old trees in pattom and namkhaneh districts in the nowshahr, northern iran. the trees quantitative characteristics of dbh, total height, slenderness coefficient, trunk height, crown length, buttress height, and canopy cover area and qualitative characteristics of crown and trunk, i.e., health, vitality, and concurr...

the purpose of this research was to assess the influence of several orchard systems involving trees trained to different leader numbers on growth, cropping, and fruit quality of two apple cultivars. the study was conducted during 1994-2007 at the fruit experimental station in samotwór, next to wrocław (south-western poland). one-year-old trees of ‘elstar’ and ‘jonagold’ cultivars on the m.9 roo...

in order to study the qualitative, quantitative characteristics of a pure common populus alba stand in polkalleh & a mixed stand of populus alba & populus nigra in karchegan, two 30-year-old stands were selected with a plantation interval ( spacing) of 2.5 × 1.5 m in each of which 30 pcs of 2 are samples were randomly selected. in each sample pc all the trees diameters were measured using a dia...

Buxus sempervirens L. (European Box, Buxaceae) has been used in ethnomedicine to treat malaria. In the course of our screening of plant extracts for antiprotozoal activity, a CH2Cl2 extract from leaves of B. sempervirens showed selective in vitro activity against Plasmodium falciparum (IC50 = 2.79 vs. 20.2 µg/mL for cytotoxicity against L6 rat cells). Separation of the extract by acid/base extr...

let  $r$ be a commutative noetherian ring and $i$ be an ideal of $r$. we say that $i$ satisfies the persistence property if  $mathrm{ass}_r(r/i^k)subseteq mathrm{ass}_r(r/i^{k+1})$ for all positive integers $kgeq 1$, which $mathrm{ass}_r(r/i)$ denotes the set of associated prime ideals of $i$. in this paper, we introduce a class of square-free monomial ideals in the polynomial ring  $r=k[x_1,ld...