Topic
Phenylurea Compounds
About: Phenylurea Compounds is a research topic. Over the lifetime, 53 publications have been published within this topic receiving 1370 citations.
Papers published on a yearly basis
Papers
TL;DR: This work devised a b a t c h process us ing cu l tu red algae exposed to f lowing sea water and used unicel lu lar green algae, selected, t e s t ed and cu l t iva t ed in l abora to ry exper imen t s.
Abstract: Mos t of t he m e t h o d s t r ied so far are based on ion exchange, adsorp t ion , prec ip i ta t ion , and so lven t ex t rac t ion , b u t none seems l ikely to s a t i s fy t he above r equ i r emen t s . We h a d t he idea t h a t mic roo rgan i sms possess m a n y of the requi red proper t ies : se lec t iv i ty for b ind ing u r an i um, easy and inexpens ive p roduc t ion of t he b iomass , o p t i m u m degree of d ispers ion for fas t b ind ing kinet ics , and no was te problems. F r o m theore t ica l cons idera t ions and technological calcula t ions we devised a b a t c h process us ing cu l tu red algae exposed to f lowing sea water . For our e x p e r i m e n t s we used unicel lu lar green algae, m u t a t e d , selected, t e s t ed and cu l t iva t ed in l abora to ry exper imen t s . I n some cu l tures the m e d i u m was enr iched b y add i ng u r a n i u m sa l t in order to d e m o n s t r a t e t h a t even h i gh concen t ra t ions of u r a n i u m are no t po isonous to t he m u t a n t s . I n some experim e n t s a low e n r i c h m e n t was used for ana ly t ica l convenience . Some resu l t s are p re sen t ed in Tab le 1. A New Insecticide Inhibits Chitin Synthesis
157 citations
TL;DR: Kinetics and mechanistic aspects of the transformation of phenylurea herbicides induced by well-defined excited triplet states are focused on and suggest that oxidation rates are mainly determined by the bimolecular rate constant for electron transfer, a rule that can possibly be extended to various organic contaminants.
Abstract: Excited triplet states of dissolved natural organic matter (DOM) are important players for the transformation of organic chemical contaminants in sunlit natural waters. The present study focuses on kinetics and mechanistic aspects of the transformation of phenylurea herbicides induced by well-defined excited triplet states, which have been chosen to model DOM triplet states having oxidative character. The aromatic ketones benzophenone, 3‘-methoxy- acetophenone, and 2-acetonaphthone were used to photogenerate their triplet states and oxidize a series of eleven substituted phenylureas. Quenching of the excited triplet states by the phenylureas was measured using laser flash photolysis in the microsecond time domain, while the oxidation kinetics of the phenylureas was followed under steady-state irradiation. Second-order rate constants for quenching and oxidation were largely identical for a given pair of ketone and phenylurea. They reached the diffusion-controlled limit (≈4 × 109 M-1 s-1) and decreased with...
157 citations
TL;DR: A simple bis-urea containing anion receptor, synthesised from ortho-phenylenediamine, has been shown to have excellent selectivity for carboxylates in solution, with a crystal structure elucidation of the benzoate complex showing four hydrogen bonds between the receptor and anion in the solid state.
120 citations
Journal Article•
TL;DR: Patients who are intermediate-stage—BCLC stage B—typically have a good performance status and often have preserved liver function, but they also have multifocal HCC within the liver, so these patients are usually not candidates for surgical resection.
116 citations
TL;DR: The location of the genes on a plasmid and a lack of selection would explain why the degradative phenotype of A. globiformis D47, as with many other pesticide-degrading bacteria, can be lost on subculture.
Abstract: Arthrobacter globiformis D47 was shown to degrade a range of substituted phenylurea herbicides in soil. This strain contained two plasmids of approximately 47 kb (pHRIM620) and 34 kb (pHRIM621). Plasmid-curing experiments produced plasmid-free strains as well as strains containing either the 47- or the 34-kb plasmid. The strains were tested for their ability to degrade diuron, which demonstrated that the degradative genes were located on the 47-kb plasmid. Studies on the growth of these strains indicated that the ability to degrade diuron did not offer a selective advantage to A. globiformis D47 on minimal medium designed to contain the herbicide as a sole carbon source. The location of the genes on a plasmid and a lack of selection would explain why the degradative phenotype, as with many other pesticide-degrading bacteria, can be lost on subculture. A 22-kb EcoRI fragment of plasmid pHRIM620 was expressed in Escherichia coli and enabled cells to degrade diuron. Transposon mutagenesis of this fragment identified one open reading frame that was essential for enzyme activity. A smaller subclone of this gene (2.5 kb) expressed in E. coli coded for the protein that degraded diuron. This gene and its predicted protein sequence showed only a low level of protein identity (25% over ca. 440 amino acids) to other database sequences and was named after the enzyme it encoded, phenylurea hydrolase (puhA gene).
113 citations
Related Topics (5)
Performance Metrics
| Year | Papers |
|---|---|
| 2020 | 1 |
| 2019 | 4 |
| 2018 | 2 |
| 2017 | 3 |
| 2015 | 3 |
| 2014 | 1 |