The objective of the present paper was to review the consumption status of meat and dairy products among Chinese residents. The research topics included production, consumption and health ...implications of dairy and meat, and the data sources included reports of national surveys, research papers and data from the National Bureau of Statistics of China. The average intake of meat, especially pork, has continued to increase in China. Pork intake increased from 37·1 g/d in 1992 to 64·3 g/d in 2012. There was a much higher margin in rural regions; pork intake of rural residents increased from 25·0 g/d in 1992 to 59·9 g/d in 2012, which resulted in a narrowed gap between urban and rural areas. Although the average intake of dairy products increased from 14·9 g/d in 1992 to 24·7 g/d in 2012, the overall level was still lower. There was a significant difference of dairy consumption between urban and rural residents. The gap of per capita consumption of milk between urban and rural households was 3·5 kg/year in 1990, reached the maximum of 16·9 kg/year in 2003, then decreased to 8·7 kg/year in 2012. In conclusion, the finding of this review sheds light on some problems with food consumption patterns in China. Effective strategies need to be adopted in order to change the consumption patterns. The consumption of milk and replacing pork with poultry or fish or other health foods should be encouraged.
Dynamic compression is a common scenario of mechanical abuse of lithium-ion batteries for electric vehicles. The safety characteristics under dynamic compression is highly different from that under ...quasi-static compression, whereas research in this field is still scarce. Here, the lateral quasi-static compression and dynamic compression of two kinds of cylindrical lithium-ion batteries are carried out. According to the first order derivative of the force to the displacement, there are six main stages of the battery behavior under lateral compression. The behavior of STAGE IV under the dynamic compression is obviously different from that under quasi-static compression. Both experimental and modeling results reveal that the dynamic load has a certain strengthening effect on the battery. For both types of batteries, the equivalent strength under high strain rate tends to be consistent. Combined with the Crushable-Foam material model and Johnson-Cook material model, the dynamic and quasi-static mechanical simulation are performed at the cell level, and the simulation results well explain the experimental phenomenon. The simulation and experimental results show that the safety warning of the cylindrical lithium-ion battery based on mechanical penetration has a certain safety margin, which can provide valuable reference for the battery safety under mechanical abuse in the future.
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•Six main deformation stages are founded under lateral mechanical abuse.•Dynamic load has a certain strengthening effect on the battery.•The mechanical penetration based failure warning method has a certain safety margin.
The failure of lithium-ion batteries under mechanical abuse is a multi-physical process involving mechanical failure, electrochemical degradation, internal electric short circuit, thermal runaway and ...structure damage. To gain a fundamental understanding of the failure mechanisms, in this work we propose a mechanical-electrochemical-thermal coupling model based on structure damage to study the failure behavior of lithium-ion battery under mechanical abuse in hard short-circuit stage from the real 3D structure and the whole battery level. The failure elements in the mechanical model are transferred into failure geometry and combined with the deformed cylindrical lithium-ion battery body. Then the short-circuit thermal power is calculated by the short-circuit model and sent to the thermal model. The electrochemical model outputs the terminal voltage and the electrochemical heat generation rate to the short-circuit model and the thermal model, respectively. The thermal model calculates cell temperature and feeds it back to the electrochemical model. The coupling model points out the fact that the internal short circuit heat is the main heat source during the short time of hard short-circuit stage under mechanical abuse. Furthermore, the coupling multi-physics model provides fundamental insights into the mechanisms of battery failure under mechanical abuse condition and can accelerate the analysis process which helps to understand the failure phenomenon in the future researches.
•This paper proposes a coupling failure model for battery under mechanical abuse.•The mechanical-electrochemical-thermal model is based on the structure damage.•The multi-physics model can simulate the battery failure under mechanical abuse well.
Abstract
Our knowledge about the evolution of guarantee network in downturn period is limited due to the lack of comprehensive data of the whole credit system. Here we analyze the dynamic Chinese ...guarantee network constructed from a comprehensive bank loan dataset that accounts for nearly 80% total loans in China, during 01/2007-03/2012. The results show that, first, during the 2007-2008 global financial crisis, the guarantee network became smaller, less connected and more stable because of many bankruptcies; second, the stimulus program encouraged mutual guarantee behaviors, resulting in highly reciprocal and fragile network structure; third, the following monetary policy adjustment enhanced the resilience of the guarantee network by reducing mutual guarantees. Interestingly, our work reveals that the financial crisis made the network more resilient, and conversely, the government bailout degenerated network resilience. These counterintuitive findings can provide new insight into the resilience of real-world credit system under external shocks or rescues.
Northeast China (NEC) is not only one of the major agricultural production areas in China, but it is also the most susceptible to climate variability. This led us to investigate the impact of climate ...change on maize potential yield and yield gaps in this region, where maize accounts for about 30% of the nation's production. The APSIM‐Maize model was calibrated and validated for maize phenology and yields. The validated model was then used to estimate potential yields, rain‐fed potential yields, and yield gaps for assessing the climate impacts on maize productivity in NEC. During maize growing seasons from 1981 to 2010, the analysis indicates a warming trend all across NEC, whereas the trends in solar radiation and total precipitation tended to decrease. When the same hybrid was specified in APSIM for all years, a simulated increase of maximum temperature resulted in a negative impact on both potential yield and rain‐fed potential yield. A simulated increase in minimum temperature produced no significant changes in potential or rain‐fed potential yield. However, the increase of minimum temperature was shown to result in a positive impact on the on‐farm yield, consistent with our finding that farmers adopted longer season hybrids for which the increase in minimum temperature provided better conditions for germination, emergence, and grain filling during night time. The gap between potential and rain‐fed potential yields was shown to be larger at locations with lower seasonal precipitation (<500 mm). Our results indicate that regions with the largest yield gaps between rain‐fed potential and on‐farm yields were located in the southeast of NEC. Within NEC, on‐farm maize yields were, on average, only 51% of the potential yields, indicating a large exploitable yield gap, which provides an opportunity to significantly increase production by effective irrigation, fertilization, herbicide, and planting density in NEC.
Fatigue experiments were performed on a polycrystalline P/M processed nickel-based superalloy, FGH96 at 600°C to investigate competing fatigue failure behaviors of the alloy. The experiments were ...performed at four levels of stress (from high cycle fatigue to low cycle fatigue) at stress ratio of 0.05. There was large variability in fatigue life at both high and low stresses. Scanning electron microscopy (SEM) was used to analyze the failure surfaces. Three types of competing failure modes were observed (surface, sub-surface and internal initiated failures). Crack initiation sites were gradually changed from the surface to the interior with the decreasing of stress level. Roles of microstructures in competing failure mechanism were analyzed. There were six kinds of fatigue crack initiation modes: (1) surface inclusion initiated; (2) surface facet initiated; (3) sub-surface inclusion initiated; (4) sub-surface facet initiated; (5) internal inclusion initiated; (6) internal facet initiated. Inclusions at surface were the life-limiting microstructures at higher stress levels. The probability of occurrence of inclusions initiated is gradually reduced with decreasing of stress level, simultaneously the probability of occurrence of facets initiated is increasing. The existence of the inclusions resulted in large life variability at higher stress levels, while heterogeneity of material caused by random combinations of grains was the main cause of fatigue variability at lower stress levels.
Using treadmill training, this study replicated human exercise conditions and triggered exercise-induced fatigue in mice to examine the potential of Pediococcus pentosaceus YF01 in delaying this ...fatigue by regulating oxidative stress and its impact on the exercise capacity and gut microbiota of mice. The exercise capacity of mice was tested by conducting exhaustion tests, determining histopathological changes in mouse tissues, detecting the levels of serum biochemical markers, and evaluating the mRNA expression levels of relevant genes. YF01 prolonged the exhaustion time of mice, increased the serum levels of oxidative stress-related markers T-AOC, CAT, and GSH, as well as GLU and LA levels in the mice. YF01 decreased the levels of hepatic-related markers AST and ALT, as well as exercise-related markers LDH, BUN, UA, and CRE in the mice. YF01 upregulated the mRNA expression of MyHc I, SIRT1, and PGC in muscle tissues, as well as SOD1, SOD2, and CAT in both liver and muscle tissues. YF01 also downregulated the mRNA expression of MyHc IIa, MyHc IIb, and MyHc IIx in muscle tissues. Furthermore, YF01 increased the abundance of beneficial bacteria such as Lactobacillus and Lachnospiraceae in the gut microbiota of mice. In conclusion, P. pentosaceus YF01 may affect the exercise capacity of mice by modulating oxidative stress levels, thereby offering novel ideas for developing of sports science and human health.
The early Cambrian Carinachitidae, a family in the subclass Conulata, are intriguing and important small shelly fossils. Their gently tapering, tube-shaped skeletons consist of convex faces separated ...from each other by broad, deep corner sulci, and they exhibit triradial, pentaradial, or predominantly tetraradial symmetry. However, the morphology of the aperture and the modes of growth of carinachitid skeletons as well as the anatomy of their soft parts are unknown. Examination of a single new, exceptionally well-preserved specimen of tetramerous Carinachites spinatus Qian, 1977, collected from the lower Cambrian Kuanchuanpu Formation in South China, reveals: (1) that its aperture is connected to a small mass of relic soft tissue and (2) that the apertural end of each of the four faces is developed into a subtriangular lappet or oral lobe that is smoothly folded toward the long axis of the tube, partially closing the tube aperture. Similarities between thorn-like spines on the faces and the oral lobes indicate that the transverse ribs were periodically displaced from the perradial portion of the aperture during formation of new ribs. In addition, the tube walls may have undergone secondary thickening during growth. The growth pattern of the tube and the spatial relationships between the tube aperture and soft parts are analogous to those of co-occurring olivooids. These findings further strengthen the previously proposed hypothesis that coeval carinachitids, olivooids, hexangulaconulariids, and Paleozoic conulariids are closely related taxa within the subphylum Medusozoa. Finally, carinachitids most likely represent an evolutionary intermediate between olivooids and hexangulaconulariids.
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•Specimens containing different artificial defects sizes were tests at RT and ET.•Fatigue life decreases significantly due to the existence of artificial defects.•The life scatter of ...specimen with similar defect under same condition is small.•A fracture-mechanic based model was proposed to evaluate the existence of a defect.
To study the influence of defects, a crack-like artificial defect was introduced at the surface of smooth specimens of a powder metallurgy nickel-based superalloy FGH96. Two kinds of size were set and fatigue tests were conducted at both room temperature (RT) and elevated temperature (ET) with several different stress levels. Results first show that the existence of surface defects significantly reduces fatigue life and the negative effect of temperature is also evident. Meanwhile, specimens with identical conditions exhibit little scatter in life which provides the possibility to evaluate fatigue lives with a relatively deterministic method. To further reveal the failure process, both macro and micro fractography were carefully examined and specimens at RT and ET show evident differences in crack initiation and propagation. Finally, a life prediction method based on the fracture mechanic was proposed. Five stress intensity calculation methods with different strategies for the surface crack in round specimens were applied and their influence on life prediction was further discussed. Given the relative high loading condition, the plasticity modification for different method is also included. Besides, this calculation method was checked for application on other loading conditions. Finally, the final stress intensity value and the parameter sensitivity analysis were also discussed.
Northeast China (NEC) is one of the major agricultural production areas in China and also an obvious region of climate warming. We were motivated to investigate the impacts of climate warming on the ...northern limits of maize planting. Additionally, we wanted to assess how spatial shifts in the cropping system impact the maize yields in NEC. To understand these impacts, we used the daily average air temperature data in 72 weather stations and regional experiment yield data from Jilin Province. Averaged across NEC, the annual air temperature increased by 0.38 °C per decade. The annual accumulated temperature above 10 °C (AAT10) followed a similar trend, increased 66 °C d per decade from 1961 to 2007, which caused a northward expansion of the northern limits of maize. The warming enabled early-maturing maize hybrids to be sown in the northern areas of Heilongjiang Province where it was not suitable for growing maize before the warming. In the southern areas of Heilongjiang Province and the eastern areas of Jilin Province, the early-maturing maize hybrids could be replaced by the middle-maturing hybrids with a longer growing season. The maize in the northern areas of Liaoning Province was expected to change from middle-maturing to late-maturing hybrids. Changing the hybrids led to increase the maize yield. When the early-maturing hybrids were replaced by middle-maturing hybrids in Jilin Province, the maize yields would increase by 9.8 %. Similarly, maize yields would increase by 7.1 % when the middle-maturing hybrids were replaced by late-maturing hybrids.
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