Selective hydrogenation of acetylene alcohols over a Pd/TiO2 coating in a capillary microreactor

Understanding the structure-activity/selectivity relationships at the molecular scale is of significant importance in assisting the development of new catalytic processes in microstructured reactors. The selective hydrogenation of 2-methyl-3-butyne-2-ol on a series of well-characterized mesostructured titania supported bimetallic PdZn thin films has been studied to clarify key factors responsible for high selectivity to the semihydrogenated product. The highest selectivity towards the semihydrogenated product (2-methyl-3-butene-2-ol, MBE) over Pd/Ti02 was 83%. The bimetallic PdZn catalyst with a Zn/Pd molar ratio of 3 demonstrated the highest selectivity towards MBE of 90% which was achieved at 60 °C with a H2 partial pressure of 0.7. Addition of a base either on the surface of the catalyst or in the liquid phase further improved selectivity to MBE towards 98%

Selective hydrogenation of acetylene alcohols over a Pd/TiO2 coating in a capillary microreactor

Understanding the structure-activity/selectivity relationships at the molecular scale is of significant importance in assisting the development of new catalytic processes in microstructured reactors. The selective hydrogenation of 2-methyl-3-butyne-2-ol on a series of well-characterized mesostructured titania supported bimetallic PdZn thin films has been studied to clarify key factors responsible for high selectivity to the semihydrogenated product. The highest selectivity towards the semihydrogenated product (2-methyl-3-butene-2-ol, MBE) over Pd/Ti02 was 83%. The bimetallic PdZn catalyst with a Zn/Pd molar ratio of 3 demonstrated the highest selectivity towards MBE of 90% which was achieved at 60 °C with a H2 partial pressure of 0.7. Addition of a base either on the surface of the catalyst or in the liquid phase further improved selectivity to MBE towards 98%

Green catalysis by nanoparticulate catalysts developed for flow processing? case study of glucose hydrogenation

Heterogeneous catalysis, flow chemistry, continuous processing, green solvents, catalyst immobilization and recycling are some of the most relevant, emerging key technologies to achieve green synthesis. However, a quantification of potential effects on a case to case level is required to provide a profound answer, whether they can lead to a superior process compared to the industrial standard. To do so, holistic environmental assessment approaches are very useful tools providing insights and decision support during the process development phase. Herein, novel heterogeneous nanoparticulate ruthenium catalysts immobilized on hyperbranched polystyrene (HPS) and nitrogen-doped carbon nanotubes (NCNT) were investigated with respect to their potential environmental impacts and improvements if utilized in an industrially highly relevant process, namely glucose hydrogenation to sorbitol. The results of a comparative Life Cycle Assessment of the alternative catalytic systems under consideration of RANEY® nickel as benchmark catalyst revealed that in particular Ru nanoparticles on porous HPS beads processed under flow-chemistry conditions have the potential to improve the greenness of the overall synthesis, but the concentration of glucose in the reaction mixture is in fact the most influential parameter

Green catalysis by nanoparticulate catalysts developed for flow processing? case study of glucose hydrogenation

Heterogeneous catalysis, flow chemistry, continuous processing, green solvents, catalyst immobilization and recycling are some of the most relevant, emerging key technologies to achieve green synthesis. However, a quantification of potential effects on a case to case level is required to provide a profound answer, whether they can lead to a superior process compared to the industrial standard. To do so, holistic environmental assessment approaches are very useful tools providing insights and decision support during the process development phase. Herein, novel heterogeneous nanoparticulate ruthenium catalysts immobilized on hyperbranched polystyrene (HPS) and nitrogen-doped carbon nanotubes (NCNT) were investigated with respect to their potential environmental impacts and improvements if utilized in an industrially highly relevant process, namely glucose hydrogenation to sorbitol. The results of a comparative Life Cycle Assessment of the alternative catalytic systems under consideration of RANEY® nickel as benchmark catalyst revealed that in particular Ru nanoparticles on porous HPS beads processed under flow-chemistry conditions have the potential to improve the greenness of the overall synthesis, but the concentration of glucose in the reaction mixture is in fact the most influential parameter

The state of neuro-oncology during the COVID-19 pandemic: a worldwide assessment.

It remains unknown how the COVID-19 pandemic has changed neuro-oncology clinical practice, training, and research efforts. We performed an international survey of practitioners, scientists, and trainees from 21 neuro-oncology organizations across 6 continents, April 24-May 17, 2020. We assessed clinical practice and research environments, institutional preparedness and support, and perceived impact on patients. Of 582 respondents, 258 (45%) were US-based and 314 (55%) international. Ninety-four percent of participants reported changes in their clinical practice. Ninety-five percent of respondents converted at least some practice to telemedicine. Ten percent of practitioners felt the need to see patients in person, specifically because of billing concerns and pressure from their institutions. Sixty-seven percent of practitioners suspended enrollment for at least one clinical trial, including 62% suspending phase III trial enrollments. More than 50% believed neuro-oncology patients were at increased risk for COVID-19. Seventy-one percent of clinicians feared for their own personal safety or that of their families, specifically because of their clinical duties; 20% had inadequate personal protective equipment. While 69% reported increased stress, 44% received no psychosocial support from their institutions. Thirty-seven percent had salary reductions and 63% of researchers temporarily closed their laboratories. However, the pandemic created positive changes in perceived patient satisfaction, communication quality, and technology use to deliver care and mediate interactions with other practitioners. The pandemic has changed treatment schedules and limited investigational treatment options. Institutional lack of support created clinician and researcher anxiety. Communication with patients was satisfactory. We make recommendations to guide clinical and scientific infrastructure moving forward and address the personal challenges of providers and researchers