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51.
Jens Moons Dr. Francisco de Azambuja Jelena Mihailovic Karoly Kozma Dr. Katarina Smiljanic Mehran Amiri Prof. Tanja Cirkovic Velickovic Prof. May Nyman Prof. Tatjana N. Parac-Vogt 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(23):9179-9186
The selective hydrolysis of proteins by non-enzymatic catalysis is difficult to achieve, yet it is crucial for applications in biotechnology and proteomics. Herein, we report that discrete hafnium metal-oxo cluster [Hf18O10(OH)26(SO4)13⋅(H2O)33] ( Hf18 ), which is centred by the same hexamer motif found in many MOFs, acts as a heterogeneous catalyst for the efficient hydrolysis of horse heart myoglobin (HHM) in low buffer concentrations. Among 154 amino acids present in the sequence of HHM, strictly selective cleavage at only 6 solvent accessible aspartate residues was observed. Mechanistic experiments suggest that the hydrolytic activity is likely derived from the actuation of HfIV Lewis acidic sites and the Brønsted acidic surface of Hf18 . X-ray scattering and ESI-MS revealed that Hf18 is completely insoluble in these conditions, confirming the HHM hydrolysis is caused by a heterogeneous reaction of the solid Hf18 cluster, and not from smaller, soluble Hf species that could leach into solution. 相似文献
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Nosrati Sahar Molavipordanjani Sajjad Emami Saeed Abedi Seyed Mohammad Talebpour Amiri Fereshteh Hosseinimehr Seyed Jalal 《Journal of Radioanalytical and Nuclear Chemistry》2020,323(1):205-211
This study presents [99mTc]BPTG-1 and [99mTc]BPTG-2 for glioblastoma imaging. In vitro cellular uptakes of these radiotracers were examined in SKOV-3, MCF-7, U87-MG, HT-29, and A549 cell lines. U87-MG cell line displayed the highest radiotracers uptakes. Biodistribution study in U87-MG tumor bearing mice revealed higher uptake of radiotracers in tumor than muscle and brain. Liver, intestine, and kidneys displayed the highest radioactivity uptakes. The main route of radiotracers elimination was hepatobiliary. Due to the brain uptake of these radiotracers, they are promising radiotracers for future studies in the diagnosis of glioblastoma.
相似文献53.
Xiaoyang Shi Hang Xiao Habib Azarabadi Juzheng Song Xiaolong Wu Xi Chen Klaus S. Lackner 《Angewandte Chemie (International ed. in English)》2020,59(18):6984-7006
The urgency to address global climate change induced by greenhouse gas emissions is increasing. In particular, the rise in atmospheric CO2 levels is generating alarm. Technologies to remove CO2 from ambient air, or “direct air capture” (DAC), have recently demonstrated that they can contribute to “negative carbon emission.” Recent advances in surface chemistry and material synthesis have resulted in new generations of CO2 sorbents, which may drive the future of DAC and its large‐scale deployment. This Review describes major types of sorbents designed to capture CO2 from ambient air and they are categorized by the sorption mechanism: physisorption, chemisorption, and moisture‐swing sorption. 相似文献
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Gh.R. Amiri M.H. YousefiS. Manouchehri M.H. KeshavarzS. Fatahian 《Journal of magnetism and magnetic materials》2011,323(6):730-734
In this work, Mn0.7Zn0.3Fe2O4 and Ni0.7Zn0.3Fe2O4 nanoparticles with super-paramagnetic properties and size distribution from 10 to 52 nm were investigated. These particles were produced by a low-temperature solid-state reaction method without the ball-milling process. The size and morphology of the nanocrystallites were determined by X-ray diffraction, transmission electron microscopy and scanning tunneling microscopy methods. Magnetic measurements such as alternating gradient field magnetometers were used to justify the super-paramagnetic properties of these nanoparticles. Their microwave absorption in the range of 8-18 GHz was studied by a vector network analyzer. Responses of the device under tests were studied. Also, the percentage of the resin, the size and thickness of the mount were determined. The band width of 2.3 GHz was obtained with reflection-loss/written-loss of −16 dB around 10.4 GHz. 相似文献
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A new, mild, and novel method is described for the efficient deoxygenation of sulfoxides to their corresponding sulfides with 1,3-dithiane at room temperature in the presence of catalytic amounts of N-bromosuccinimide (NBS), 2,4,4,6-tetrabromo-2,5-cyclohexadienone (TABCO), or Br(2) as the source of electrophilic bromine. 相似文献
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In this paper, we present the parallelization of tabu search on a network of workstations using PVM. Two parallelization strategies are integrated: functional decomposition strategy and multi-search threads strategy. In addition, domain decomposition strategy is implemented probabilistically. The performance of each strategy is observed and analyzed. The goal of parallelization is to speedup the search in finding better quality solutions. Observations support that both parallelization strategies are beneficial, with functional decomposition producing slightly better results. Experiments were conducted for the VLSI cell placement, an NP-hard problem, and the objective was to achieve the best possible solution in terms of interconnection length, timing performance (circuit speed), and area. The multiobjective nature of this problem is addressed using a fuzzy goal-based cost computation. 相似文献
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