نتایج جستجو برای: β diketones

تعداد نتایج: 177869  

پایان نامه :وزارت علوم، تحقیقات و فناوری - دانشگاه علامه طباطبایی 1388

عاملهای شناختی، شخصیتی و موقعیتی متعددی یافت شده است که می توانند با پرخاشگری ارتباط داشته باشند. فهم چگونگی ارتباط درونی این عاملها برای پیش بینی، سنجش، و درمان پرخاشگری زندانیانی که سابقه رفتارهای پرخاشگرانه را دارند، بسیار اساسی است. پژوهشهای قبلی نقش بالقوه ای را برای توانایی حل مساله اجتماعی بعنوان یک میانجیگر بین تکانشگری و پرخاشگری پیشنهاد کرده اند. ( موران و همکاران، 2002). علاوه بر این...

Journal: :J. Chem. Soc., Trans. 1893

Bahareh Sadeghi, Fereshteh Karimi

1,2-Diketones have been reacted in one-pot method with 1,2-diamines at room temperature with ZnO nanoparticles as a catalyst. ZnO nanoparticles as an available and reusable catalyst is used for the synthesis of Quinoxalinein improved yields.

2017
Michael J. McCoy Kimberly A. Hoppe Parr Kim E. Anderson Jim Cornish Matti Haapala John Greivell

Recently described scientific literature has identified the airborne presence of 2,3-butanedione (diacetyl) and 2,3-pentanedione at concentrations approaching or potentially exceeding the current American Conference of Industrial Hygienists' (ACGIH) Threshold Limit Values (TLVs) at commercial coffee roasting and production facilities. Newly established National Institutes of Occupational Safety...

Journal: :Beilstein Journal of Organic Chemistry 2008
Basudeb Basu Bablee Mandal Sajal Das Pralay Das Ashis K Nanda

A simple, chemoselective transfer hydrogenation of aryl aldehydes with the aid of Amberlite((R)) resin formate (ARF), a stable H-donor, in the presence of catalytic ruthenium trichloride is described. Aromatic aldehydes and 1,2-diketones are reduced efficiently and selectively, while aryl ketones remain unchanged. Several other potentially reducible groups attached to the aromatic moiety are un...

Abbas Ali Jafari Abdolhamid Bamoniri, BiBi Fatemeh Mirjalili, Fatemeh Abasaltian

Silica supported phosphorus pentoxide (P2O5·SiO2) is an efficient catalyst for synthesis of 1,3,5-substituted pyrazoles via the condensation of 1,3-diketones and hydrazines. Simplicity of procedure, mild condition, being solvent-free, high yields, and easy workup are some advantages of this protocol.

Afrooz Baharvand Cobra Rostami Farhad Rajabi Mehr Shahram Moradi,

In present paper a simple procedure for the synthesis of enaminones without catalyst from 1,3-diketones that reacted with primary or secondary amines in ethanol as solvent, as well as the reaction of enaminones with unsaturated esters such as dimethyl acetylene dicarboxylate are reported.

Journal: :iranian journal of chemistry and chemical engineering (ijcce) 2008
shahram moradi farhad rajabi mehr afrooz baharvand cobra rostami

in present paper a simple procedure for the synthesis of enaminones without catalyst from 1,3-diketones that reacted with primary or secondary amines in ethanol as solvent, as well as the reaction of enaminones with unsaturated esters such as dimethyl acetylene dicarboxylate are reported.

2015
Shannon H. Gaffney Anders Abelmann Jennifer S. Pierce Meghan E. Glynn John L. Henshaw Lauren A. McCarthy Jason T. Lotter Monty Liong Brent L. Finley

Over the last decade, concerns have been raised about potential respiratory health effects associated with occupational exposure to the flavoring additives diacetyl and 2,3-pentanedione. Both of these diketones are also natural components of many foods and beverages, including roasted coffee. To date, there are no published studies characterizing workplace exposures to these diketones during co...

نمودار تعداد نتایج جستجو در هر سال

با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید