Comparison of Lithium-Ion Anode Materials Using an Experimentally Verified Physics-Based Electrochemical Model

Researchers are in search of parameters inside Li-ion batteries that can be utilized to control their external behavior. Physics-based electrochemical model could bridge the gap between Li+ transportation and distribution inside battery and battery performance outside. In this paper, two commercially available Li-ion anode materials: graphite and Lithium titanate (Li4Ti5O12 or LTO) were selected and a physics-based electrochemical model was developed based on half-cell assembly and testing. It is found that LTO has a smaller diffusion coefficient (Ds) than graphite, which causes a larger overpotential, leading to a smaller capacity utilization and, correspondingly, a shorter duration of constant current charge or discharge. However, in large current applications, LTO performs better than graphite because its effective particle radius decreases with increasing current, leading to enhanced diffusion. In addition, LTO has a higher activation overpotential in its side reactions; its degradation rate is expected to be much smaller than graphite, indicating a longer life span

New Method for Determination of Residual Strength Parameters and Critical Damage Value

Residual strength and critical damage parameters are worthy to evaluate the stability of engineered rock masses. In this paper, new thinking, repeated load test on a single specimen was proposed to measure the residual strength of the rock. And author proposed to modify the critical damage value based on residual constitutive energy. The test results showed that: (1) the residual strength of rock is mainly controlled by the confining pressure, without a clear relationship with the confining pressure and stress path of the initial loading failure. (2) The residual strength parameters of the rock specimens under repeated loading test are consistent with the conventional triaxial test. Most importantly, the proposed method is relatively less dispersion, cheap, reliable, and time-saving. (3) The corrected critical damage value was reasonable. Relevant test methods can provide a useful reference for the determination of residual strength parameters and critical damage value

Pressure-Controlled Motion of Single Polymers through Solid-State Nanopores

Voltage-biased solid-state nanopores are well established in their ability to detect and characterize single polymers, such as DNA, in electrolytes. The addition of a pressure gradient across the nanopore yields a second molecular driving force that provides new freedom for studying molecules in nanopores. In this work, we show that opposing pressure and voltage bias enables nanopores to detect and resolve very short DNA molecules, as well as to detect near-neutral polymers.Engineering and Applied SciencesPhysic

Risk Prioritization and Management in Gas Stations by using Fuzzy AHP and IPA Analysis

1107-1116Gasoline industry is the main pillar of Pakistan’s economy and is of immense importance. This industry is confronted by diverse risks which significantly affect its performance resulting in decreased economic contribution. On the other side, published literature merely analyzes this industry and suggests directions to improve it. Thus, this study is a kickoff step in this regard, and its purpose is to study the relationship between risk factors, importance, and performance of gasoline industry, which is based on questionnaire data collected from three districts, viz., Gujranwala, Gujrat and Sialkot of Punjab, Pakistan. In total, 159 completed questionnaires were collected having consistency ratio (CR) less than 0.1. Acquired stats were investigated using the latest techniques of multi-criteria decision making routines, viz., fuzzy analytic hierarchy process (Fuzzy AHP) and importance performance analysis (IPA) software Expert Choice 2000. Among the five main risk types faced by gasoline industry, transportation / tanker unloading (importance, 0.467: rank, 1) was the most, whereas, the least significant factor was miscellaneous category (importance, 0.049: rank, 5). Moreover, the most significant factor which showed high importance with high performance was driving carelessness / accidents (importance, 0.278; performance, 3.32), high importance with low performance was uncontrolled vapor released (importance, 0.087; performance, 2.53), low importance with low performance was fire / explosion (importance, 0.021; performance, 2.66) and low importance with high performance was overfill / crossover (importance, 0.027; performance, 4.11). Thus, this work identifies, prioritizes and highlights the areas where improvement is needed to encounter risk and increase quality function development of gas stations

Methylation of H3-Lysine 79 Is Mediated by a New Family of HMTases without a SET Domain

AbstractThe N-terminal tails of core histones are subjected to multiple covalent modifications, including acetylation, methylation, and phosphorylation [1]. Similar to acetylation, histone methylation has emerged as an important player in regulating chromatin dynamics and gene activity [2–4]. Histone methylation occurs on arginine and lysine residues and is catalyzed by two families of proteins, the protein arginine methyltransferase family and the SET-domain-containing methyltransferase family [3]. Here, we report that lysine 79 (K79) of H3, located in the globular domain, can be methylated. K79 methylation occurs in a variety of organisms ranging from yeast to human. In budding yeast, K79 methylation is mediated by the silencing protein DOT1. Consistent with conservation of K79 methylation, DOT1 homologs can be found in a variety of eukaryotic organisms. We identified a human DOT1-like (DOT1L) protein and demonstrated that this protein possesses intrinsic H3-K79-specific histone methyltransferase (HMTase) activity in vitro and in vivo. Furthermore, we found that K79 methylation level is regulated throughout the cell cycle. Thus, our studies reveal a new methylation site and define a novel family of histone lysine methyltransferase

Purification and Functional Characterization of SET8, a Nucleosomal Histone H4-Lysine 20-Specific Methyltransferase

AbstractBackground: Covalent modifications of histone N-terminal tails play fundamental roles in regulating chromatin structure and function. Extensive studies have established that acetylation of specific lysine residues in the histone tails plays an important role in transcriptional regulation. Besides acetylation, recent studies have revealed that histone methylation also has significant effects on heterochromatin formation and transcriptional regulation. Histone methylation occurs on specific arginine and lysine residues of histones H3 and H4. Thus far, only 2 residues on histone H4 are known to be methylated. While H4-arginine 3 (H4-R3) methylation is mediated by PRMT1, the enzyme(s) responsible for H4-lysine 20 (H4-K20) methylation is not known.Results: To gain insight into the function of H4-K20 methylation, we set out to identify the enzyme responsible for this modification. We purified and cloned a novel human SET domain-containing protein, named SET8, which specifically methylates H4 at K20. SET8 is a single subunit enzyme and prefers nucleosomal substrates. We find that H4-K20 methylation occurs in a wide range of higher eukaryotic organisms and that SET8 homologs exist in C. elegans and Drosophila. We demonstrate that the Drosophila SET8 homolog has the same substrate specificity as its human counterpart. Importantly, disruption of SET8 in Drosophila reduces levels of H4-K20 methylation in vivo and results in lethality. Although H4-K20 methylation does not correlate with gene activity, it appears to be regulated during the cell cycle.Conclusions: We identified and characterized an evolutionarily conserved nucleosomal H4-K20-specific methyltransferase and demonstrated its essential role in Drosophila development

A method for estimating yield of maize inbred lines by assimilating WOFOST model with Sentinel-2 satellite data

Maize is the most widely planted food crop in China, and maize inbred lines, as the basis of maize genetic breeding and seed breeding, have a significant impact on China’s seed security and food safety. Satellite remote sensing technology has been widely used for growth monitoring and yield estimation of various crops, but it is still doubtful whether the existing remote sensing monitoring means can distinguish the growth difference between maize inbred lines and hybrids and accurately estimate the yield of maize inbred lines. This paper explores a method for estimating the yield of maize inbred lines based on the assimilation of crop models and remote sensing data, initially solves the problem. At first, this paper analyzed the WOFOST(World Food Studies)model parameter sensitivity and used the MCMC(Markov Chain Monte Carlo) method to calibrate the sensitive parameters to obtain the parameter set of maize inbred lines differing from common hybrid maize; then the vegetation indices were selected to establish an empirical model with the measured LAI(Leaf Area Index) at three key development stages to obtain the remotely sensed estimated LAI; finally, the yield of maize inbred lines in the study area was estimated and mapped pixel by pixel using the EnKF(Ensemble Kalman Filter) data assimilation algorithm. Also, this paper compares a method of assimilation by setting a single parameter. Instead of the WOFOST parameter optimization process, a parameter representing the growth weakness of the inbred lines was set in WOFOST to distinguish the inbred lines from the hybrids. The results showed that the yield estimated by the two methods compared with the field measured yield data had R2: 0.56 and 0.18, and RMSE: 684.90 Kg/Ha and 949.95 Kg/Ha, respectively, which proved that the crop growth model of maize inbred lines established in this study combined with the data assimilation method could initially achieve the growth monitoring and yield estimation of maize inbred lines