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181.
A Self‐Reporting Photocatalyst for Online Fluorescence Monitoring of High Throughput RAFT Polymerization 下载免费PDF全文
Dr. Jonathan Yeow Dr. Sanket Joshi Dr. Robert Chapman Prof. Cyrille Boyer 《Angewandte Chemie (International ed. in English)》2018,57(32):10102-10106
Translating controlled/living radical polymerization (CLRP) from batch to the high throughput production of polymer libraries presents several challenges in terms of both polymer synthesis and characterization. Although recently there have been significant advances in the field of low volume, high throughput CLRP, techniques able to simultaneously monitor multiple polymerizations in an “online” manner have not yet been developed. Here, we report our discovery that 5,10,15,20‐tetraphenyl‐21H,23H‐porphine zinc (ZnTPP) is a self‐reporting photocatalyst that can mediate PET‐RAFT polymerization as well as report on monomer conversion via changes in its fluorescence properties. This enables the use of a microplate reader to conduct high throughput “online” monitoring of PET‐RAFT polymerizations performed directly in 384‐well, low volume microtiter plates. 相似文献
182.
Bulten HJ Anthony PL Arnold RG Arrington J Beise EJ Belz E van Bibber K Bosted PE van den Brand JF Chapman MS Coulter KP Dietrich FS Ent R Epstein M Filippone BW Gao H Gearhart RA Geesaman DF Hansen J Holt RJ Jackson HE Jones CE Keppel CE Kinney E Kuhn SE Lee K Lorenzon W Lung A Makins NC Margaziotis DJ McKeown RD Milner RG Mueller B Napolitano J Nelson J O'Neill TG Papavassiliou V Petratos GG Potterveld DH Rock SE Spengos M Szalata ZM Tao LH White JL Zeidman B 《Physical review letters》1995,74(24):4775-4778
183.
Abe F Albrow MG Amidei D Antos J Anway-Wiese C Apollinari G Areti H Atac M Auchincloss P Azfar F Azzi P Bacchetta N Badgett W Bailey MW Bao J de Barbaro P Barbaro-Galtieri A Barnes VE Barnett BA Bartalini P Bauer G Baumann T Bedeschi F Behrends S Belforte S Bellettini G Bellinger J Benjamin D Benlloch J Bensinger J Benton D Beretvas A Berge JP Bertolucci S Bhatti A Biery K Binkley M Bird F Bisello D Blair RE Blocker C Bodek A Bokhari W Bolognesi V Bortoletto D Boswell C Boulos T Brandenburg G 《Physical review letters》1995,74(15):2900-2904
184.
Johnson CF Brown CS Wheeler RM Sager JC Chapman DK Deitzer GF 《Photochemistry and photobiology》1996,63(2):238-242
Oat (Avena sativa cv Seger) seedlings were irradiated with IR light-emitting diode (LED) radiation passed through a visible-light-blocking filter. Infrared LED irradiated seedlings exhibited differences in growth and gravitropic response when compared to seedlings grown in darkness at the same temperature. Thus, the oat seedlings in this study were able to detect IR LED radiation. These findings call into question the use of IR LED as a safe-light for some photosensitive plant response experiments. These findings also expand the defined range of wavelengths involved in radiation-gravity (light-gravity) interactions to include wavelengths in the IR region of the spectrum. 相似文献
185.
Swartz M Abrams GS Adolphsen CE Averill D Ballam J Barish BC Barklow T Barnett BA Bartelt J Bethke S Blockus D Bonvicini G Boyarski A Brabson B Breakstone A Bulos F Burchat PR Burke DL Cence RJ Chapman J Chmeissani M Cords D Coupal DP Dauncey P DeStaebler HC Dorfan DE Dorfan JM Drewer DC Elia R Feldman GJ Fernandes D Field RC Ford WT Fordham C Frey R Fujino D Gan KK Gatto C Gero E Gidal G Glanzman T Goldhaber G Gomez Cadenas JJ Gratta G Grindhammer G Grosse-Wiesmann P Hanson G Harr R Harral B 《Physical review letters》1990,64(24):2877-2880
186.
Kral JF Abrams GS Adolphsen CE Averill D Ballam J Barish BC Barklow T Barnett BA Bartelt J Bethke S Blockus D Bonvicini G Boyarski A Brabson B Breakstone A Bulos F Burchat PR Burke DL Cence RJ Chapman J Chmeissani M Cords D Coupal DP Dauncey P DeStaebler HC Dorfan DE Dorfan JM Drewer DC Elia R Feldman GJ Fernandes D Field RC Ford WT Fordham C Frey R Fujino D Gan KK Gatto C Gero E Gidal G Glanzman T Goldhaber G Gomez Cadenas JJ Gratta G Grindhammer G Grosse-Wiesmann P Hanson G Harr R Harral B 《Physical review letters》1990,64(11):1211-1214
187.
Burchat PR King M Abrams GS Adolphsen CE Averill D Ballam J Barish BC Barklow T Barnett BA Bartelt J Bethke S Blockus D Bonvicini G Boyarski A Brabson B Breakstone A Bulos F Burke DL Cence RJ Chapman J Chmeissani M Cords D Coupal DP Dauncey P DeStaebler HC Dorfan DE Dorfan JM Drewer DC Elia R Feldman GJ Fernandes D Field RC Ford WT Fordham C Frey R Fujino D Gan KK Gatto C Gero E Gidal G Glanzman T Goldhaber G Gomez Cadenas JJ Gratta G Grindhammer G Grosse-Wiesmann P Hanson G Harr R Harral B 《Physical review D: Particles and fields》1990,41(11):3542-3545
188.
Abachi S Derrick M Kooijman P Musgrave B Price L Repond J Sugano K Blockus D Brabson BB Brom J Jung C Ogren H Rust DR Snyder A Cork B Akerlof C Chapman J Errede D Ken MT Kesten P Meyer DI Neal H Nitz D Thun R Tschirhart R Baringer P Bylsma BG Debonte R Low EH McIlwain RL Miller DH Ng CR Rangan K Shibata E 《Physical review D: Particles and fields》1990,41(7):2045-2056
189.
Kathy E. Yokobata John M. Jordan Orvrlle Chapman Curt Krerl 《Photochemistry and photobiology》1986,43(4):391-401
Abstract— We have developed a procedure called a plaque reduction assay to assess the biological activity of duplex circular DNA modified by covalent adduct formation with psoralen derivatives. The replicating form (RF) of bacteriophage DNA modified by photochemical addition of a psoralen derivative was introduced into bacterial cells using the CaCI2 transfection method. The transfected cells. plated upon a confluent lawn of cells permissive for the bacteriophage in the inoculum, provided a measure of the reduction in infectivity of the RF DNA which resulted from its covalent modification. Use of this assay is illustrated in studies which screened and compared the activities of several recently synthesized psoralen derivatives. We describe two new compounds. β-(8-psoralenoxy)-ethanol and β-(8-psoralenoxy)ethylamine that are significantly more active than either 8-methoxypsoralen or trioxsalen in the biological assay 相似文献
190.
J. M. Lynch S. H. T. Harper S. J. Chapman D. A. Veal 《Applied biochemistry and biotechnology》1984,9(4):379-380
Production of composts on the farm from surplus straw might provide a low-cost biotechnological approach for increasing the
value of this lignocellulosic waste. Successful composting depends on the conversion of the polysaccharides (cellulose and
hemicelluloses) of straw by inoculated microorganisms to products that can promote plant growth when applied to the land.
None of the potentially useful products we have identified are produced by cellulolytic organisms. We have therefore studied
mixed populations in which noncellulolytic bacteria depend for growth on the products of fungal cellulolysis. The nature and
yield of bacterial products depends not only on conditions within the compost, but also on the microbial inoculants used.
Under defined laboratory conditions, using pure cellulose, N2 is fixed by the anaerobic bacteriumClostridium butyricum in association with a cellulolytic fungus such asTrichoderma sp. A similar association has been achieved on straw withPenicillium corylophilum as the cellulolytic fungus.
Cellulolytic fungi can also provide available substrates for the production of bacterial polysaccharides that can improve
the structure of unstable soils. The yield of polysaccharide and its efficacy in soil aggregate stabilization again varies
with the inoculants used.
Such composts can thus contribute to plant nutrition and to soil structure. The adoption ofTrichoderma spp. as the cellulolytic inoculants would further extend the potential value of the compost to include the biocontrol of
plant pathogens. 相似文献