The kinetics of oxidation of Ni (Ni + co)-Nbc superalloys represented by the alloy Ni-Nbc and (Ni + co)-Nbc was studied. The alloys were studied in the cast state. It was found that the alloys oxidize according to a p...
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The kinetics of oxidation of Ni (Ni + co)-Nbc superalloys represented by the alloy Ni-Nbc and (Ni + co)-Nbc was studied. The alloys were studied in the cast state. It was found that the alloys oxidize according to a parabolic law. The analysis of diffusion-oxidation processes at a temperature of 1100 degrees c in air indicates an increase in heat resistance as a result of intensification of scale sintering and the formation on the surface of superalloys of a diffusion barrier layer of chromium, aluminum, and niobium oxides. The research result determines the prospects of creating industrial alloys for power engineering based on Ni (Ni + co)-Nbc superalloys.
Microbial communities are fundamental components driving critical biogeochemical carbon (c), nitrogen (N) and sulfur (S) cycles in groundwater ecosystems. The reduction-oxidation (redox) potential is one important env...
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Microbial communities are fundamental components driving critical biogeochemical carbon (c), nitrogen (N) and sulfur (S) cycles in groundwater ecosystems. The reduction-oxidation (redox) potential is one important environmental factor influencing the microbial community composition. Here, we developed a bio-trap method using in-situ sediment as a matrix to collect aquifer sediment samples and evaluate the response of microbial composition and c/N/S cycling functions to redox variations created by providing sole O-2, joint O-2 and H-2, and sole H-2 to three wells. Illumina sequencing analyses showed that the microbial communities in the bio-trap sediment could respond quickly to redox changes in the wells, demonstrating that this bio-trap method is promising for detecting microbial variation in the aquifer sediment. The microbial metabolic functions related to c, N and S cyclings and organic pollutants degradation were predicted by the Kyoto Encyclopedia of Genes and Genomes (KEGG) approach. It was found that the joint O-2 and H-2 injection produced medium oxidation-reduction potential (ORP -346 and -614 mV) and enhanced more microbial functions than sole O-2 or H-2,H- which mainly include oxidative phosphorylation, most carbon source metabolism, various pollutants degradation, and nitrogen and sulfur metabolism. Moreover, the functional genes encoding phenol monooxygenase, dioxygenase, nitrogen fixation, nitrification, aerobic and anaerobic nitrate reductase, nitrite reductase, nitric oxide reductase, and sulfur oxidation increased. These findings tell us the contaminant bioremediation and N, S metabolism can be promoted by adjusting ORP realised by injecting joint O-2 and H-2.
In this study, SiO@graphite@c@Al2O3 (SiO@G@c@A) composites are synthesized by varying the content of Al2O3, and their morphology and structure and their electrochemical performance are investigated in detail. The resu...
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In this study, SiO@graphite@c@Al2O3 (SiO@G@c@A) composites are synthesized by varying the content of Al2O3, and their morphology and structure and their electrochemical performance are investigated in detail. The results indicate that the SiO/G@c@A-2 composite exhibits a specificcapacity of 977.1 mA h g(-1) at a current density of 0.1 A g(-1) with a coulombic efficiency of 71.15%. Even after 100 cycles at a current density of 0.5 A g(-1), it retains a delithiated specificcapacity of 640.7 mA h g(-1) and a capacity retention rate of 73.56%. Moreover, when the current density is raised to 2 A g(-1), it maintains a delithiated capacity of 568.4 mA h g(-1) and a capacity retention rate of 58.51%. The excellent electrochemical performance is ascribed to the synergistic effect of different components. The inclusion of graphite enhances overall conductivity while mitigating the volume expansion of the SiO. The application of asphalt pyrolyticcarbon as a coating effectively isolates the SiO from the electrolyte, further reducing volume expansion and enhancing conductivity. The introduction of Al2O3 can absorb trace amounts of hydrogen fluoride (HF) generated during charge and discharge processes. Additionally, it facilitates the formation of an AlF3 film on the particle surfaces, which hinders and decelerates electrolyte dissolution into the electrode. The prepared composites exhibit promising prospects as lithium-ion battery anode materials. [GRAPHIcS] .
Needled composites have stronger interlaminar properties compared to two-dimensional fiber composite structures due to the introduction of z-directional fibers in the fiber composite layup. An effective multi-scale fi...
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Needled composites have stronger interlaminar properties compared to two-dimensional fiber composite structures due to the introduction of z-directional fibers in the fiber composite layup. An effective multi-scale finite element model is developed in this paper for the complex structure of needle-punched composites. Three scales, namely fRVE, pRVE, and lRVE, are modeled from the fiber scale, the delamination scale, and the laminate scale. using ABAQUS, periodic boundary conditions are applied to the RVEs at different scales to obtain the effective mechanical properties of various RVEs. Meanwhile, the effect of needling density on the needled composites is predicted by applying the above multi-scale model. The increase of needling density can enhance the out-of-plane effective mechanical properties of the composites, but it also weakens the in-plane effective mechanical properties. The maximum error of the elastic modulus calculation is 17.68% with that of the reference, thus verifying the rationality of the multi-scale model.
The use of ozone in food processing has become an eco-friendly, cost-effective way to manage insect pests and improve grain quality. The present study examined the efficacy of different ozone concentrations (500-1000 ...
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The use of ozone in food processing has become an eco-friendly, cost-effective way to manage insect pests and improve grain quality. The present study examined the efficacy of different ozone concentrations (500-1000 ppm), exposure time (2-6 h), and grain moisture content (11-15%, wb) on mortality of different developing stages (egg, larvae, and pupae) and adult of callosobruchus maculatus. Treated Mung bean was also analyzed for in-vitro protein digestibility (IVPD), grain hardness, and germination rate. A comparison between untreated (control) and treated mung bean samples at optimized conditions was conducted to determine the influence of ozone on proximate and mineral analysis, thermal and pasting properties. c. maculatus pupae and adults were least susceptible to ozonation, with mortality rates of 11.11 and 13.04-100%, respectively. In the optimal condition of 11.17% grain moisture content, 1000 ppm ozone concentration, and 2 h exposure time, mortality of different life stages (egg, larvae, pupae, and adults) of c. maculatus was calculated as 104.07%, 90.15%, 86.82%, and 83.55%, respectively. The corresponding values of IVPD, hardness, and grain germination were 67.85%, 57.43 N, and 87.74%, respectively. There was a noticeable decrease in protein, fat, and mineral content in ozone-treated mung bean compared to the control. Furthermore, enhancement in thermal and pasting properties of ozonated mung beans suggest that ozone can be utilized to develop high quality grain products' while ensuring their safety.
One can write dependently typed functional programs in coq, and prove them correct in coq;one can write low-level programs in c, and prove them correct with a c verification tool. We demonstrate how to write programs ...
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One can write dependently typed functional programs in coq, and prove them correct in coq;one can write low-level programs in c, and prove them correct with a c verification tool. We demonstrate how to write programs partly in coq and partly in c, and interface the proofs together. The Verified Foreign Function Interface (VeriFFI) guarantees type safety and correctness of the combined program. It works by translating coq function types (and constructor types) along with coq functional models into VST function-specifications;if the user can prove in VST that the c functions satisfy those specs, then the c functions behave according to the user-specified functional models (even though the c implementation might be very different) and the proofs of coq functions that call the ccode can rely on that behavior. To achieve this translation, we employ a novel, hybrid deep/shallow description of coq dependent types.
cu-based catalysts are boosting electrocatalysts in cO2 reduction reactions to high-value multicarbon (c2+) products. Because of the unstable cu+ species and the unclear microscopic structure in reactions, cu-based ca...
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cu-based catalysts are boosting electrocatalysts in cO2 reduction reactions to high-value multicarbon (c2+) products. Because of the unstable cu+ species and the unclear microscopic structure in reactions, cu-based catalysts still face significant challenges of low selectivity and poor durability at high current density. Herein, we report a thermodynamically driven comproportionation strategy for forming a cu-0/cu+/cu-0 interface to stabilize cu+ species. When tested in a flow cell containing neutral electrolyte, the sample showed a high c2+ products Faradaic efficiency (FEc2+) of 92.3% at a partial current density of 276.9 mA cm(-2). In a membrane electrode assembly, the sample achieved a 90.1% FEc2+ and maintained continuous operation for over 50 h at industrial current density. Further investigation demonstrates outstanding FEc2+ of >80% at a large industrial current of 10 A. Mechanism studies reveal that the cu-0/cu+/cu-0 interface lowers the energy barrier for c-ccoupling in the reaction, thus facilitating the conversion of cO2 to c2+ products. {GRAPHIAcAL ABSTRAcT}
Separation logic has become an important tool for formally capturing and reasoning about the ownership patterns of imperative programs, originally for paper proof, and now the foundation for industrial static analyses...
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Separation logic has become an important tool for formally capturing and reasoning about the ownership patterns of imperative programs, originally for paper proof, and now the foundation for industrial static analyses and multiple proof tools. However, there has been very little work on program testing of separation- logic specifications in concrete execution. At first sight, separation-logic formulas are hard to evaluate in reasonable time, with their implicit quantification over heap splittings, and other explicit existentials. In this paper we observe that a restricted fragment of separation logic, adopted in the cN proof tool to enable predictable proof automation, also has a natural and readable computational interpretation, that makes it practically usable in runtime testing. We discuss various design issues and develop this as a c+cN source to c source translation, Fulminate. This adds checks - including ownership checks and ownership transfer - for ccode annotated with cN pre- and post-conditions;we demonstrate this on nontrivial examples, including the allocator from a production hypervisor. We formalise our runtime ownership testing scheme, showing (and proving) how its reified ghost state correctly captures ownership passing, in a semantics for a small c-like language.
In this work, the life prediction of c/Siccomposites subjected to stochastic load spectra with hold cycles is investigated using a damage-based micromechanical model. Relationships between the fiber's architectur...
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In this work, the life prediction of c/Siccomposites subjected to stochastic load spectra with hold cycles is investigated using a damage-based micromechanical model. Relationships between the fiber's architecture (i.e., 1D unidirectional, 2D crossply and plain-woven, 2.5D woven, and 3D braided), stochastic load spectra, hold cycles, fiber-fragmentation probability (FFP), and composite fatigue-life degradation rate (FFDR) are established. Experimental FFDR and FFP in different c/Siccomposites are predicted. Under the low fatigue peak stress, the FFDR is the highest during increasing stochastic stress for 1D and 3D c/Sic and is the highest during decreasing stochastic stress for 2D and 2.5D c/Sic. Under the high fatigue peak stress, the FFDR is the highest during decreasing stochastic stress for 1D, 2D, 2.5D and 3D c/Sic. The FFDR at the constant stochastic stress level is the lowest under the low or high fatigue peak stress.
Acacia mangium plantations in Sabah, Malaysia are seriously affected by a vascular wilt and canker disease caused by a species of ceratocystis. A similar and devastating disease occurs in Indonesia and is caused by th...
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Acacia mangium plantations in Sabah, Malaysia are seriously affected by a vascular wilt and canker disease caused by a species of ceratocystis. A similar and devastating disease occurs in Indonesia and is caused by the fungal pathogen ceratocystis manginecans. A closely related fungus, ceratocystis fimbriata sensu stricto, is a common soil-borne pathogen of sweet potato (Ipomoea batatas) in areas of Malaysia where A. mangium is grown. This study characterised the species causing wilting on A. mangium and compared it with the I. batatas pathogen using DNA sequence-based comparisons used artificial inoculations to assess the effect of the A. mangium pathogen on Acacia auriculiformis and Acacia crassicarpa and considered the ability of the sweet potato pathogen to cause disease on the three Acacia species. DNA sequence comparisons confirmed that isolates from diseased A. mangium were c. manginecans and those on sweet potato were c. fimbriata s.s. ceratocystis manginecans was pathogenic on all Acacia spp., with A. mangium being most susceptible followed by =A. auriculiformis and A. crassicarpa. Pathogenicity tests showed that c. fimbriata s.s. from sweet potato is not able to cause disease on any of the three Acacia spp. considered. This study also confirmed that c. manginecans is the primary cause of ceratocystis canker and wilt disease in Sabah and that the sweet potato fungus, c. fimbriata s.s., poses no threat to propagated Acacia spp.
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