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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.

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.

We present evidence that ethanol alters intracellular poly(adenosine diphosphoribose) metabolism and we further describe the mechanism by which ethanol exerts its effect on polymer synthesis. One percent ethanol stimulates polymer accumulation as much as 2.5-fold but does not alter polymer degradation in intact cells following DNA damage. Ethanol directly stimulates polymer synthesis following low doses of DNA damage induce by deoxyribonuclease I in a nucleotide-permeable cell system that does not possess a functional polymer turnover system. Ethanol has no measurable effect on polymer synthesis in undamaged nucleotide-permeable cells or in permeable cells treated with high doses of deoxyribonuclease I. Ethanol concentrations that stimulate poly(adenosine diphosphoribose) polymerase activity in vitro specifically lower KDNA without affecting KNAD or Vmax. The results clearly show that ethanol alters the binding of this enzyme to the DNA component of chromatin and that this altered binding is responsible for the activation of the enzyme. Altered affinity of poly(adenosine diphosphoribose) polymerase and perhaps other regulatory proteins for chromatin may play an important role in the pathology of alcohol.

Etude experimentale de la distribution du champ de disruption dielectrique d'environ 100 dispositifs Al−Si−SiO 2 −Al dont les couches d'oxyde, d'epaisseur 200-900 A, sont preparees par faisceau laser

Lower-cost alternatives to platinum electrocatalysts are being explored for the sustainable production of hydrogen, but often trial-and-error approaches are used for their development. Now, principles are elucidated that suggest pathways to rationally design efficient metal-free electrocatalysts based on doped graphene.

The performance of solid-state ballasts for operating fluorescent lamps measured in a controlled laboratory environment is described and compared with the performance of typical core-coil type ballasts. Parameters of interest include efficiency, conducted and radiated EMI and results of some accelerated lamp life tests. The experimental design of the demonstration to retrofit three floors of an office building with solid-state ballasts to evaluate their reliability and energy savings in a variety of applications is described.

Abstract Newly accessible shale deposits and other unconventional sources of natural gas have dramatically increased global gas reserves and are regarded as major future energy sources. Shale gas drilling began in Texas and is expanding throughout the U.S. and globally. In Texas and other regions, large population centers overlie these deposits. As a result, city residents increasingly come into contact with extraction activities. The proximity of drilling activities to residential areas raises a number of concerns, including noise, dust and emissions hazards, public safety, diminished quality of life, and effects on neighborhood aesthetics and property values. Cities in Texas address these concerns through setback ordinances that regulate the distance between gas wells and residences, schools, floodplains, etc. Although the state of Texas permits drilling 200 ft (61 m) from residences, many municipalities in the Dallas–Fort Worth Metroplex (DFW) have established longer setback distances. This paper analyzes the purpose and basis for setback distances among 26 municipalities in DFW. Findings show that there is no uniform setback distance, distances have increased over time, and, rather than technically-based, setbacks are political compromises. For policy makers confronted with urban shale gas drilling, deriving setback distances from advanced emissions monitoring could decrease setback distance ambiguity.

Abstract Data from many real-world applications can be high dimensional and features of such data are usually highly redundant. Identifying informative features has become an important step for data mining to not only circumvent the curse of dimensionality but to reduce the amount of data for processing. In this paper, we propose a novel feature selection method based on bee colony and gradient boosting decision tree aiming at addressing problems such as efficiency and informative quality of the selected features. Our method achieves global optimization of the inputs of the decision tree using the bee colony algorithm to identify the informative features. The method initializes the feature space spanned by the dataset. Less relevant features are suppressed according to the information they contribute to the decision making using an artificial bee colony algorithm. Experiments are conducted with two breast cancer datasets and six datasets from the public data repository. Experimental results demonstrate that the proposed method effectively reduces the dimensions of the dataset and achieves superior classification accuracy using the selected features.

Abstract not Available.