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Abstract Lignin is considered as a renewable and sustainable resource for producing value-added aromatic chemicals and functional carbon materials. Herein, we develop a one-step catalyst-free depolymerization strategy to convert lignin into aryl monomers and carbon nanospheres simultaneously. Importantly, microwave-assisted depolymerization (MAD) in conjunction with dichloromethane (CH2Cl2) vapors is developed. The total mass yield of guaiacols reached the highest amount of 225.1 mg/g at 600 °C, and the highest yields of phenols (49.0 mg/g) and aromatic hydrocarbons (155.1 mg/g) were obtained at 700 °C. Hydrogen radicals and hydrogen chloride (HCl) are in-situ formed from CH2Cl2, significantly decreasing the activation barrier and reforming pyrolysis vapors to promote the formation of aryl monomers. Interestingly, uniform carbon nanospheres with an average size of 140 nm were produced as co-products at 700 °C. The microwave “hot-spots”, allied with the continuous surface erosion and the decrease in surface energy of lignin-derived carbon precursors by CH2Cl2 vapor, can be considered the driving force for the ultimate formation of carbon nanospheres. The CH2Cl2/MAD system produces aryl monomers (26.8 wt% yield) and carbon nanospheres (36.6 wt% yield) at 700 °C. We provide a facile, intriguing and scalable approach to convert lignin to valuable aryl monomers and sustainable carbon materials that can be applied in the chemistry, energy and environmental fields.

The 17th International Conference on Knowledge Management was held in the historic city of Potsdam, Germany. Since the conference was among the first post-pandemic face to face conferences, the overall theme of the 17th edition of the ICKM conference rightly focused on “Knowledge, Uncertainty and Risks: From individual to global scale†at different levels of analysis and agency. This document highlighted one of the local keynote speeches by Prof. Ortwin Renn, scientific director at the International Institute for Advanced Sustainability Studies (IASS) in Potsdam (Germany) and professor for environmental sociology and technology assessment at the University of Stuttgart.

The processing of graphene coated NiO–Ni anode using one CVD system delivered high Li-ion battery performance.

Fact sheet describing state-specific impacts that global warming will have on the people, ecosystems, and wildlife in Colorado.

Data management plan for the grant "IRES Track II - Cape Horn ASIs: Climate change and disease ecology at the southern end of the Americas." Research giving students the opportunity to be trained in quantitative experimental design and work as part of a multinational research collaboration to study infectious disease emergence in one of the few remaining pristine places on Earth. The Cape Horn Biosphere Reserve (CHBR) off the southern tip of South America protects pristine ecosystem is perfect for this type of graduate student training. The CHBR is part of the sub-Antarctic Magellanic ecoregion, which is globally significant because it houses the worlds southernmost forest biome, contains numerous endemic species, is remote, and is relatively free of anthropogenic impacts. The research questions themselves will be flexible, but organized thematically. Specifically, this IRES Track-II will focus on the merging molecular genetic analysis using a mobile next generation sequencing lab with mist netting and arthropod trapping to investigate the impacts of wildlife disease on local biodiversity and community structure. Secondarily, eDNA and traditional wildlife disease monitoring approaches will be applied to understand the potential for zoonosis and understanding ecological factors that contribute to, or inhibit, zoonosis. Resultantly, participation in this program will help train the next generation of scientists with the skills needed to make meaningful contributions to the study of ecology, conservation, and wildlife disease ecology.

Fact sheet describing state-specific impacts that global warming will have on the people, ecosystems, and wildlife in South Dakota.

The customer-sited PV market in the United States depends on state policies emerging from electric utility industry restructuring. These policies, most of which have appeared since 1996, reduce both the first cost and improve operating benefits. This analysis determines the breakeven turnkey cost of a PV system, from the customer ownership perspective, on a state by state basis. The results of this work are used by industry to target high-value markets and by policy makers to identify options which will result in the greatest economic and market development. Still intangible external PV benefits, such as environmental value, are also analyzed and gauged against existing/potential policy actions.

Fact sheet describing state-specific impacts that global warming will have on the people, ecosystems, and wildlife in Oregon.

Abstract Commercially available lightweight-flexible CIGS solar cells are investigated under the Low-Intensity-Low-Temperature (LILT) conditions that exist at Mars, Jupiter, and Saturn. Current density-voltage measurements, concentrated solar, and external quantum efficiency measurements are performed under varying temperatures and illumination intensities to determine the applicability and performance of flexible CIGS in outer planetary conditions. The well-known metastability of the CIGS absorber is observed as a result of a barrier to minority carrier extraction at the CIGS/CdS interface under higher intensity illumination. However, despite the low temperatures and low intensities experienced in deeper space, the presence of this barrier does not significantly affect the performance of the solar cells under LILT conditions. This is attributed to the lower photogeneration rate of carriers particularly at conditions relative to Saturn and Jupiter, which appears to be less than the thermionic emission rate across the barrier and therefore the carrier extraction is relatively unaffected under these illumination conditions. At elevated temperatures and/or intensities such as at AM0 and conditions relative to Mars, however, the higher carrier generation rate results in the appearance of large series resistance and a significant loss of fill factor at irradiation levels greater than 1-sun AM0. Proton irradiation of the solar cells systematically reduces the performance, predominately through the formation of defect states in the absorber layer, the presence of which is increasingly more prohibitive in LILT conditions due to the low thermal energy of the minority carriers and the subsequent increased effect of SRH recombination.

The piezoelectric energy harvester has become a new powering option for some low-power electronic devices such as MEMS (Micro Electrical Mechanical System) sensors. Piezoelectric materials can collect the ambient vibrations energy and convert it to electrical energy. This thesis is intended to demonstrate the behavior of a piezoelectric energy harvester system at elevated temperature from room temperature up to 82°C, and compares the system’s performance using different piezoelectric materials. The systems are structured with a Lead Magnesium Niobate-Lead Titanate (PMN-PT) single crystal patch bonded to an aluminum cantilever beam, Lead Indium Niobate-Lead Magnesium Niobate-Lead Titanate (PIN-PMN-PT) single crystal patch bonded to an aluminum cantilever beam and a bimorph cantilever beam which is made of Lead Zirconate Titanate (PZT). The results of this experimental study show the effects of the temperature on the operation frequency and output power of the piezoelectric energy harvesting system. The harvested electrical energy has been stored in storage circuits including a battery. Then, the stored energy has been used to power up the other part of the system, a wireless resonator force sensor, which uses frequency conversion techniques to convert the sensor’s ultrasonic signal to a microwave signal in order to transmit the signal wirelessly.