To prepare Pd catalysts for formate oxidation with superior anti-poisoning performance and Pd utilization, a facile strategy is employed by combining in-situ deposition and subsequent Pd growth. The ...high resolution transmission electron microscopy is used to observe the morphologies, confirming the existence of Pd/SnO2 interfaces and the uniform Pd layer on SnO2 through in-situ deposition. After subsequent growth, the Pd crystalline structure is better developed and the size of identifiable Pd moieties increased, as evidenced by X-ray diffraction (XRD) patterns and high resolution transmission electron microscopy (HRTEM) images. The electrochemical characterization indicates that Pd/SnO2 interfaces together with increased size of Pd moieties promotes the Pd anti-poisoning performance. Besides, with subsequent Pd growth, the Pd utilization is also improved, as evidenced by the increase in area of Pd oxide reduction peak. Considering the facile preparation, superior performance and flexibility of combining in-situ Pd deposition and subsequent metals growth, the strategy is believed to be of promising potential for wide range catalysts development and application.
Through in-situ deposition and subsequent growth, the anti-poisoning performance and utilization of Pd as catalyst for formate oxidation is greatly improved. Display omitted
•Pd layer of atomic thickness can be deposited on SnO2 with tunable coverage through in-situ redox reaction.•Pd/SnO2 interface is beneficial for improving the anti-poisoning performance of Pd catalyst during formate oxidation.•Through subsequent Pd growth, the anti-poisoning performance and utilization are simultaneously enhanced.•The electrochemical active surface area of Pd catalyst is 3704 cm2 mgPd−1, near to the maximum value of 4360 cm2 mgPd−1.•The mass activity reaches 3.1 A mgPd−1 after i-t test of 2500 s.
A scaleup route for a first-generation covalent KRASG12C inhibitor ARS-2102 was devised, featuring an “early cross-coupling” strategy to construct the tetra-substituted atropisomeric biaryl scaffold. ...An iterative diastereomeric recrystallization enabled an effective chiral resolution of key intermediate 24. A global deprotection followed by chemoselective functionalization afforded ARS-2102 in excellent yield and diastereomeric enrichment. This chromatography-free sequence was successfully executed on kilogram scale.
This paper focus on mechanism of a digital to analog converter induced by electrochemical decay. The electrical parameters and the I/V characteristics of the digital to analog converter are abnormal, ...and the 11-pin of the device are open because of the decay. By the scanning electron microscope inspection and the energy spectrum analysis to the decay, the carbon and the oxygen of the decay are relatively high, and there exists decaying elements chlorine. The mechanism of the electrochemical decay is analysed, the reason of the electrochemical decay contains three elements: moisture, decaying elements and electric field. Moreover, the 11-pin has the worst decay resulted from the strongest electric field, inducing the opening of 11-pin and the failure of the digital to analog converter.
We report a five-step synthesis of 2-cyano-5-formyl-4-methyl-1H-indole through sequential functionalization of readily available 4-methyl-1H-indole. Cyano and aldehyde functionalities are ...regioselectively installed at the 2 and 5 position, respectively. The sequence is concise and high-yielding, amenable for kilogram scale production.
Relevance. The scientific and technological development of society made modern people believe in the possibility of conquering nature by the power of reason. Modern society feels the unattainability ...of this goal: anthropocentrism cannot cope with climate change and natural disasters. The comprehension of the harmony between nature and man becomes topical.Purpose. The study aims to determine the specifics of philosophical comprehension of the harmony of nature and man in modern society.Methodology. To achieve the goal, the historical-philosophical method is used (with its help the development of the discourse on the harmony of nature from Antiquity to modernity is traced), the historical-comparative method (to find the differences between pantheism and environmentalism) and others.Results. The doctrine of philosophers devoted to the theme of harmony between man and nature is considered in the article, and their distinctive features are highlighted. It is determined that in modern societies the search for harmony between nature and man plays the role of basic ideology, which displaces anthropocentrism. Eco-philosophy emerges from pantheism but has unique features: political projectivity, preventiveness, ethical turn of ontology, and reactionism. Modern sustainable development societies feel the connection of three phenomena: human, nature, and security. It is existential challenges that motivate them to green reforms . Ancient societies, on the other hand, felt either indifference to nature (the Middle Ages) or non-committal admiration (Antiquity). Early modernity proceeded from an anthropocentric basic attitude, which predetermined the acuteness of environmental challenges of modernity.Conclusions. The study can be used for historical and philosophical research on the topic of eco-philosophy, as well as for comprehension of modern trends in Western philosophical thought. The results of the study can also be used as a philosophical basis for the implementation of environmental, enlightenment and educational projects.
Radiometric calibration of synthetic aperture radar (SAR) is an important work related to pixel values and the backscattering coefficient of ground targets. With a consideration of the difference ...between near space and spaceborne, airborne platforms, this paper proposes the radiometric calibration method which is applicable to near space platform. A radiometric calibration model of near space SAR is established, and it is analyzed and validated by experimental data.
This paper focus on failure analysis of a full wave phase sensitive demodulator induced by surface defect. A phase sensitive demodulator fails, inducing a big AC signal after the post-amplifier. ...According to the failure analysis, the failure reason of the phase sensitive demodulator is the surface defect in the interface of the Si and the SiO2. The surface defect decreases the current of the operational amplifier of the phase sensitive demodulator, making the signal suppression of the low frequency noise worse. The failure reappearance is performed by adding a parallel resistance between the power supply and the base of the triode of the operational amplifier. Moreover, three improvement measurements that include electrical test, cleaning and process are proposed, solving the failure phenomenon of the full wave phase sensitive demodulator.
This paper focus on failure analysis of a PROM at low temperature induced by process deviation. An abnormal pulse occurs from "0" to "1" of the reading data of the PROM at -10 °C. The failure ...mechanism of the PROM is analysed. By testing, the reference voltage of the comparator of the failure PROM is smaller than the normal PROM especially in the low temperature. The reference voltage gets smaller because of not only the NMOS but also the resistor, which result in the same reference voltage change trend with the decrease of the temperature. With the extremum of the process parameters, a simulation at different temperature is performed, which has the same waveform and the same failure temperature with the test. To avoid this failure, the maximum allowable deviation of the resistance of the resistor is 8% with the noise tolerance of 30 mV.
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