Humans have traditionally sought provisioning services from rural areas, but society is becoming increasingly aware of other that areas provide to human beings, agroecosystem services. At the same time, however, certain dysservices can be identified. The analysis and a key point consider in decision-making processes provides tool for acting on sustainability. Notwithstanding, few approaches dai...

A series of Sillén–Aurivillius layered oxyhalides with a single- and double-perovskite layer, Bi4MO8X (M = Nb, Ta; X Cl, Br) AA?Bi3M2O11Cl (A, A? Sr, Ba, Pb, Bi; M Ti, Ta), have been recently demonstrated as promising photocatalysts for visible-light-induced water splitting due to relatively high energy valence bands arising from strong interactions between Bi-6s O-2p orbitals. Herein, we repor...

وراثت مقاومت سفیدبالک گلخانه، Trialeurodes vaporariorum Westwood (Hemiptera: Aleyrodidae)، به دو ترکیب ایمیداکلوپرید و کلرپایریفوس مورد مطالعه قرار گرفت. در این پژوهش، از جمعیت فیلستان ورامین (FL) عنوان والد مقاوم فردیس کرج (FR) حساس استفاده شد. مقدار ترتیب حدودا 62/13 91/14 برابر بود. عدم وجود اختلاف معنی‌دار LC50 روی تلاقی‌های F1 (R♂×S♀) Fʹ1 (R♀×S♂) نشان داد که T. نوع اتوزومی (غیرجنسی) است. ه...

A number of C-2 aminoalkenylthio-carbapenem derivatives possessing both the (5R,6R, 8S)- and the (5R,6S,8R)-stereochemistries have been prepared from the olivanic acids MM 22382 and MM 22383, respectively. Certain members of this new class of compounds displayed potent, broad spectrum antibacterial activity as well as improved stability to human kidney homogenate.

(1S,2S,5R,6S)-6-(3,4-Methylenedioxyphenyl)-3,7-dioxabicyclo[3.3.0]octan-1,2-diol ((+)-1-hydroxysamin 1) was synthesized, starting from olefin 8. Stereoselective alpha-hydroxylation was achieved after converting 8 to aldehyde 13. Resulting unstable alpha-hydroxy aldehyde 14 was then transformed to (+)-1-hydroxysamin (1). This is a new efficient synthetic route to 1,2-oxygenated 6-arylfurofuran l...

Some Europium(III) dibenzoylmethide and benzoylacetonate complexes have been subjected to Mössbauer studies at liquid nitrogen temperature. An attempt is made to discuss covalency in these complexes in terms of 6s, 4f and/or 5d orbital participation in the bond formation. Small linewidths are correlated to less symmetric structures. Resonance effects reflect the polymeric nature of these chelates.

The lithium enolate of (2S,3S,5S,6S)-dimethoxy-2,3-dimethyl-1,4-dioxane-5,6-dithiocarboxylate undergoes stereoselective mono- and/or dialkylations to afford two new stereogenic centers. The alkylation products obtained possessed a cis stereochemistry, which was confirmed by the synthesis of natural 4'-O-methylpiscidic acid dimethyl ester .

We give a construction for a new family of Group Divisible Designs (6s+ 2, 3, 4; 1, 2) using Mutually Orthogonal Latin Squares for all positive integers s. Consequently, we have proved that the necessary conditions are sufficient for the existence of GDD’s of block size four with three groups, λ1=2 and λ2=1.

The dominant one-loop vacuum-polarization correction to atomic wave functions are evaluated for the 6s–7s parity nonconserving (PNC) E1 transition amplitude in cesium. This correction increases the size of the PNC amplitude by 0.4% and thus increases the difference between the experimental value of the weak charge QW and the one predicted by the standard model.