Impact of elution impurities on DOTA and NOTA labeling with two commercial 68Ge/68Ga generators

Journal of Radioanalytical and Nuclear Chemistry - Different amounts of commercial p-SCN-Bn-DOTA and p-SCN-Bn-NOTA (Macrocyclics, USA) were labeled with 68Ga from IGG-100 purified and unpurified...     

Fabrication of a Novel Polymeric Scaffold for Amperometric Laccase Biosensor

Present work displays the preparation of an electrochemical biosensor using a conjugated polymer and laccase enzyme for catechol quantification in samples. The biosensing system is based on an enzyme immobilization on polymer modified graphite transducer surface. For that purpose, a random conjugated polymer, thienothiophene‐benzoxadiazole‐alt‐benzodithiophene (BOTT), was coated onto a graphite electrode surface via drop casting method followed by immobilization of a biomolecule (laccase) for sensing experiments. Herein, for the first time, we proposed a BOTT polymer as an inexpensive and effective way to fabricate highly sensitive and fast response biosensors. The proposed sensing system possessed superior properties with 0.38 μM limit of detection and 110.81 μA mM^?1 sensitivity. Furthermore, cyclic voltammetry and scanning electron microscopy techniques were used to examine the surface modifications. The proposed system could be useful for many future studies for catechol quantification in environmental samples.© 2019 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2019, 57, 2333–2339     

Method for obtaining the rate coefficient of a second-order gas evolving reaction

The method is based on the measurement of pressures produced by collection of the gas during equal time intervals. It was applied to HCOOH decomposition in H₂SO₄.     

Syntheses,electrochemical and spectroelectrochemical characterization of benzothiadiazole and benzoselenadiazole based random copolymers

Three novel donor-acceptor-donor type random copolymers based on benzothiadiazole (BTh) and benzoselenadiazole (BSe) were synthesized via Pd (0) catalyzed Suzuki polycondensation reaction. The two acceptor units were coupled with electron rich moieties which are carbazole (CZ), fluorene (FL) and silafluorene (SiFL). Monomers were characterized using ¹H and ¹³C-NMR spectroscopy. The number and weight average molecular weights of the polymers were calculated using gel permeation chromatography (GPC). All three polymers were electrochemically and spectroelectrochemically characterized. PBThBSeCZ, PBThBSeFL and PBThBSeSiFL showed only p-dopable character and their doping/dedoping potentials were determined as 1.4 V/1.2 V, 1.53 V/1.27 V and 1.8 V/1.3 V, respectively. Corresponding HOMO energy levels were calculated as ?5.85 eV, ?6.05 eV and ?6.15 eV whereas LUMO energy levels were found to be ?3.67 eV, ?3.84 eV and ?3.77 eV, respectively. PBThBSeCZ had lower HOMO level and band gap than PBThBSeFL and PBThBSeSiFL due to its increased electron donating capability of nitrogen atom in carbazole unit.     

Incorporation of different conjugated linkers into low band gap polymers based on 5,6‐Bis(octyloxy)‐2,1,3 benzooxadiazole for tuning optoelectronic properties

Four new 2,1,3‐benzooxadiazole‐based donor–acceptor conjugated polymers, namely poly{9‐(9‐heptadecanyl)‐9H‐carbazole‐alt‐5,6‐bis(octyloxy)‐4,7‐di(selenophen‐2‐yl)benzo[c][1,2,5]oxadiazole)}(PSBSC), poly{9‐(9‐heptadecanyl)‐9H‐carbazole‐alt‐5,6‐bis(octyloxy)‐4,7‐di(furan‐2‐yl)benzo[c][1,2,5]oxadiazole)}(PFBFC), poly{9,9‐dioctyl‐9H‐fluorene‐alt‐5,6‐bis(octyloxy)‐4,7‐di(selenophen‐2‐yl)benzo[c][1,2,5]oxadiazole)}(PSBSFL), and poly{9,9‐dioctyl‐9H‐fluorene‐alt‐5,6‐bis(octyloxy)‐4,7‐di(furan‐2‐yl)benzo[c][1,2,5]oxadiazole)}(PFBFFL), were synthesized via Stille polycondensation reaction. All polymers were found to be soluble in common organic solvents such as chloroform, tetrahydrofuran, and chlorobenzene. Their structures were verified by ¹H‐NMR and the molecular weights were determined by gel permeation chromatography (GPC). The polymer films exhibited broad absorption bands. Among all polymers, photovoltaic cells based on the device structure of ITO/PEDOT:PSS/PSBSC:PC₇₁BM(1:3, w/w)/LiF/Al revealed an open‐circuit voltage of 0.62 V, a short circuit current of 7.63 mA cm^?2 and a power conversion efficiency of 1.89%. This work demonstrates a good example for tuning absorption range, energy level, and photovoltaic properties of the polymers with different spacers and donor units can offer a simple and effective method to improve the efficiency of PSCs. © 2016 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2016 , 54, 2459–2467     

Dismantle or remanufacture?

In this paper we study a firm’s disposition decision for returned end-of-use products, which can either be remanufactured and sold, or dismantled into parts that can be reused. We formulate this problem as a multi-period stochastic dynamic program, and find the structure of the optimal policy, which consists of monotonic switching curves. Specifically, if it is optimal to remanufacture in a given period and for given inventory levels, then it is also optimal to remanufacture when the inventory of part(s) is higher or the inventory of remanufactured product is lower.     

Effects of cosolvents cetyltrimethylammonium bromide on the thresholds for nucleation of nitrogen in aqueous solutions

The decomposition of ammonium nitrite in water creates a supersaturated solution of nitrogen. The same process occurs in water-organic solvent mixtures. Acetone, dioxane, dimethylsulfoxide (DMSO) and dimethylformamide (DMF) are the cosolvents used in this study. The limits of supersaturation of nitrogen (C _SL /mol L^–1) were determined in all of these solvent mixtures by releasing the dissolved gas sonicationally and measuring the volume of released gas. C _SL was generally increased in the presence of cosolvents. The effectiveness sequence of organic solvents was found to be as DMF SL and all of the measured quantities of this study were generally affected by micelle formation.     

The impact of [1,2,5]chalcogenazolo[3,4-f]-benzo[1,2,3]triazole structure on the optoelectronic properties of conjugated polymers

Two novel conjugated near-infrared (NIR) absorbing donor–acceptor type copolymers comprising benzodithiophene as the donor and [1,2,5]chalcogenazolo[3,4-f]-benzo[1,2,3]triazole derivatives as the acceptors, spaced with thiophene as the π-bridge, were designed and synthesized via Stille polycondensation reaction. The effect of acceptor strength on optoelectronic properties was targeted and investigated. Branched alkyl chains (the extended 2-octyl-1-dodecyl alkyl chain;  C₈C₁₂) were introduced to 5H-[1,2,3]triazolo[4′,5′:4,5]benzo[1,2-c][1,2,5]thiadiazole and 5H-[1,2,3]triazolo[4′,5′:4,5]benzo[1,2-c][1,2,5]selenadiazole for enhanced solubility of polymers which ease the processability hence device constructions. The strongly electron-withdrawing units lead to a substantial change in the absorption properties via promotion of the intramolecular charge transfer band alongside the π–π* transition. The resultant soluble polymers were characterized via cyclic voltammetry to determine highest occupied molecular orbital and lowest unoccupied molecular orbital energy levels as −5.00 and −3.92 eV for PSBT and −4.86 and −4.04 eV for PSeBT, respectively. Electronic band gaps of the copolymers were calculated as 1.08 eV for PSBT and 0.82 eV for PSeBT, respectively. NIR absorbing copolymers were used to construct electrochromic devices.