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The absolute atomic mass of

The antiexplosion performance of an explosion-proof wall made of engineered cementitious composite was studied, using small-scale explosion-proof walls made of different materials and sizes that were subjected to on-site blasting. The dynamic responses of these walls were evaluated under blast loading using overpressure test system, digital image correlation (DIC) full-field strain testing, and high-speed photography recording of the crushing process. Analysis of the results of the overpressure and strain tests revealed the effect of the wall height on the overpressure behind the wall. Increasing the height of the explosion-proof wall can improve the protection ratio of the wall by more than 2%. The variation of full-field strain of different materials at the same burst ratio was obtained. The engineered cementitious composite explosion-proof wall was obviously superior to that of ordinary concrete in strain control on the back-explosion surface. These theoretical results provide references for the design of explosion-proof walls.

We introduce a framework for simulating a variety of nontrivial, socially motivated behaviors that underlie the orderly passage of pedestrians through doorways, especially the common courtesy of opening and holding doors open for others, an important etiquette that has been overlooked in the literature on autonomous multi-human animation. Emulating such social activity requires serious attention to the interplay of visual perception, navigation in constrained doorway environments, manipulation of a variety of door types, and high-level decision making based on social considerations. To tackle this complex human simulation problem, we take an artificial life approach to modeling autonomous pedestrians, proposing a layered architecture comprising mental, behavioral, and motor layers. The behavioral layer couples two stages: (1) a decentralized, agent-based strategy for dynamically determining the well-mannered ordering of pedestrians around doorways, and (2) a state-based model that directs and coordinates a pedestrian's interactions with the door. The mental layer is a Bayesian network decision model that dynamically selects appropriate door-holding behaviors by considering both internal and external social factors pertinent to pedestrians interacting with one another in and around doorways. Our framework addresses the various door types in common use and supports a variety of doorway etiquette scenarios with efficient, real-time performance.

Corrugated-board explosion-proof wall is the main means to prevent explosion shock wave damage, and it is important to study the effect of different corrugated plates on the shock wave. Using a high-speed schlieren experimental system and an air overpressure test system, the wave-blocking characteristics of different forms of corrugated plates are comprehensively studied. The schlieren images were used to analyze the influence that the corrugation shape of a corrugated plate has on the shock wave propagation characteristics. The results show that the reflection process of the triangular-, trapezoidal-, and half-cylindrical-shaped corrugated plates exhibit differences. The number of reflected waves from the triangular corrugated plate is much greater than that from the other corrugated plates, and it will consume more energy. The diffraction wave-front velocity has a trend of initially decreasing and then increasing and is also reduced by different degrees by the reflection. Comparative analysis of the schlieren images and the air shock wave overpressure test shows that plates corrugated with different corrugation shapes decrease the diffraction overpressure peak and exhibit a hysteresis.

The absolute atomic mass of $^{208}$Pb has been determined with a fractional uncertainty of $7\times 10^{-11}$ by measuring the cyclotron-frequency ratio $R$ of $^{208}$Pb$^{41+}$ to $^{132}$Xe$^{26+}$ with the high-precision Penning-trap mass spectrometer Pentatrap and computing the binding energies $E_{\text{Pb}}$ and $E_{\text{Xe}}$ of the missing 41 and 26 atomic electrons, respectively, with the ab initio fully relativistic multi-configuration Dirac-Hartree-Fock (MCDHF) method. $R$ has been measured with a relative precision of $9\times 10^{-12}$. $E_{\text{Pb}}$ and $E_{\text{Xe}}$ have been computed with an uncertainty of 9.1 eV and 2.1 eV, respectively, yielding $207.976\,650\,571(14)$ u (u$=9.314\,941\,024\,2(28)\times 10^{8}$ eV/c$^2$) for the $^{208}$Pb neutral atomic mass. This result agrees within $1.2\sigma$ with that from the Atomic-Mass Evaluation (AME) 2020, while improving the precision by almost two orders of magnitude. The new mass value directly improves the mass precision of 14 nuclides in the region of Z=81-84 and is the most precise mass value with A>200. Thus, the measurement establishes a new region of reference mass values which can be used e.g. for precision mass determination of transuranium nuclides, including the superheavies., Comment: 8 pages, 4 figures, to be published in EPJA

In augmented reality, interactive shadow casting between virtual and real objects is crucial for the consistency of the appearance of integrated scenes. Since real shadow-casting objects may not be fully visible in live videos, simulating the shadows that they cast onto virtual objects based on 3D reconstruction will fail. To address this issue, we propose a framework for simulating shadow interactions in live outdoor videos based on shadow edges. The simulation framework consists of two components: real-time casting shadow detection from live videos with moving viewpoints and generation of shadow volumes. First, we propose a novel split-based shadow detection framework that accounts for moving viewpoints. Then, a visual-perception-guided adaptive sampling strategy is developed to generate high-quality shadow volumes. The experimental results demonstrate that our algorithm achieves visually consistent shadow interactions for live outdoor videos, which significantly enhances the photorealism of the generated scenes for augmented reality (AR) applications.

A new material model of magnesium alloys, combining both Hill&rsquo, 48 yield function and Cazacu&rsquo, 06 yield function, was developed and programmed into LS-DYNA using user subroutine, in which both slip dominant and twinning/untwinning dominant hardening phenomena were included. First, a cyclic load test was performed, and its finite element analysis was carried out to verify the new material model. Then, the deformation behaviors of the magnesium crash box subjected to the compressive impact loading were investigated using the developed material model. Compared with the experimental results, the new material model accurately predicted the deformation characteristics of magnesium alloy parts. Additionally, the effect of the thickness distribution, initial deflection and contact friction coefficient in simulation models on deformation behaviors were investigated using this validated material model.

A pair of separation column packed with different hydrogen absorption materials (Pd/k and 4A molecular sieves) respectively, whose hydrogen isotopic effect is opposite, is used in Thermal Cycling Absorption Process (TCAP), and its result of hydrogen isotopes separation is better than the traditional TCAP. A dynamic simulation method for the pair of column TCAP system is developed. For a certain percentage of binary gas mixtures of hydrogen isotopes (H2 and D2) injected into the twin columns system, from simulation results, it can be obtained the binary gas concentration distribution in the two columns after a different number of cycles. Furthermore, the separation process can be optimized. Moreover, it can be seen that the hydrogen isotopes separation effect of twin columns TCAP is almost twice that of the traditional TCAP.

In the process of sodium chlorate electrolysis production, chemical precipitation is often used to remove the sulfate radical in the crystallization mother liquor which leads to the dichromate deposit to salt sludge together with sulfate, and finally causes chromium pollution. The nanofiltration membrane and freezing crystallization integrated technology was presented to treat crystallization mother liquor. The research conducted in this work shows that, Na2Cr2O7 concentration was lower than 0.05 g/L, Na2SO4 concentration was lower than 1 g/L in the nanofiltration permeate and it could be recycled for brine refining stage avoiding the chromium pollution caused by subsequent treatment. The content of Na2Cr2O7 in salt sludge was less than 8.5 ppm below the 10 ppm discharge standards. Then, the nanofiltration concentrate was frozen, Na2SO4 crystallized and precipitated. The supernatant mainly containing sodium dichromate could recycle to the electrolytic system. This method not only could recycle sodium dichromate, avoiding chrome sludge generated, but also could remove sulfate radicals. Key words: Sodium chlorate, chrome sludge, nanofiltration, freezing crystallization, sodium dichromate recycling, sodium sulfate.

Diacylglycerol acyltransferase (DGAT1; EC 2.3.1.20) is the key enzyme governing the terminal step of triacylglycerol synthesis in plant seeds. The aims here were to isolate and characterize a full-length cDNA encoding DGAT1 from the sesame (Sesamum indicum L.) cultivar ‘Wanzhi1’ (oil content 55 ± 2 %; SiDGAT1); and to over-express that gene in Arabidopsis (Arabidopsis thaliana L.) and soybean (Glycine max L. Merr.). The 1,629-bp open reading frame of the SiDGAT1 cDNA encoded a protein of 543 amino acids, which showed high similarity to other plant DGAT1s. The transcript of the SiDGAT1 gene was differentially abundant among organs in sesame. The highest transcript abundance was found in the developing seeds. The expression of the SiDGAT1 cDNA driven by the cauliflower mosaic virus 35S-promoter was able to restore to near normal oil content and the fatty acid composition phenotypes of the Arabidopsis mutant AS11 (an AtDGAT1). Over-expression of SiDGAT1 in several lines of Arabidopsis thaliana ‘Col 0’ resulted in increases in oil content; and in seed weight. The ratio of eicosenoic acid (C20:1) was increased, whereas that of oleic acid (C18:1) was decreased in transgenic Arabidopsis plants. The SiDGAT1 was also used to transform soybean. Compared to controls, the mean increase in oil content was 1.75 and 1.39 % respectively in T2 and T3 transgenic soybean lines. Further, SiDGAT1 transcript abundance was correlated with increased seed size and 100-seed weight, but did not alter the fatty acid composition of the seed oil.

With the premium bull plays a growing important role in cattle industry, semen detection technology based on individual identification and phylogenetic relationship is paid more and more attention. In order to lay the foundation for the establishment of the China Holstein bull identification method, this research takes 20 Chinese Holstein dairy bull’s blood and their corresponding semen, and then extracts the DNA both from the blood and semen, analysis the genetic polymorphisms of 10 microsatellite loci (TGLA227, INRA23, TGLA122, BM2113, SPS115, ETH3, ETH225, MCM158, MAF45 and UMN0108) by microsatellite marker, discuss the feasibility of this method used to individual identification. The results showed that Chinese Holstein dairy bull genetic diversity in the ten microsatellite loci were both high, and the average polymorphic information content of TGLA227, which highest, is 0.8162, ETH225 has the lowest, which is 0.6224. Use STR loci to identify the bull’s semen, the cumulative individual identification capacity is 99.99 %, which indication that 10 STR loci can be used to the frozen semen quality test and cows individual identification.

In this paper, we present a full-body motor control mechanism that generates coordinated and diverse motion during a reaching action. Our framework animates the full human body (stretching arms, flexing of the spine, as well as stepping forward) to facilitate the desired end effector behavior. We propose a hierarchical control system for controlling the arms, spine, and legs of the articulated character and present a controller-scheduling algorithm for coordinating the sub-controllers. High-level parameters can be used to produce variation in the movements for specific reaching tasks. We demonstrate a wide set of behaviors such as stepping and squatting to reach low distant targets, twisting and swinging up to reach high lateral targets, and we show variation in the synthesized motions.

The Atomic Mass Evaluation (AME), started in the 1960s, is the most reliable source for comprehensive information related to atomic masses. It provides the best values for the atomic masses and their associated uncertainties by evaluating experimental data from decay, reactions, and mass spectrometry. In this thesis, the philosophy and the most important features of the Ame will be discussed in detail. The most recent developments of the latest mass table (AME2016), such as molecular binding energy, energy correction of the implantation measurements, and the relativistic formula for the alpha-decay process, will be presented. Another part of this thesis concerns the data analysis from the Penning-trap spectrometer ISOLTRAP at ISOLDE/CERN. The new results are included in the global adjustment and their influences on the existing masses are discussed. The last part of this thesis is related to the systematic error studies of the ISOLTRAP multi-reflection time-of-flight mass spectrometer, using an off-line ion source and the on-line proton beam. From the analysis of the selected measurements, I found that the systematic error is much smaller than the statistical uncertainties obtained up to now.; L’évaluation des masses atomiques (Ame), commencée dans les années 1960, est la source la plus fiable d’informations complètes sur les masses atomiques. Elle fournit les meilleures valeurs pour les masses atomiques et les incertitudes associées en évaluant les données expérimentales de désintégration, de réactions et de la spectrométrie de masse. Dans cette thèse, la philosophie et les caractéristiques les plus importantes de l’Ame seront discutées en détail. Les développements les plus récents de l’évaluation, AME2016, tels que l’énergie de liaison moléculaire, la correction d’énergie des mesures par implantation, et la formule relativiste pour le processus de décroissance alpha, seront présentés. Une autre partie de cette thèse concerne l’analyse des données du spectromètre à piège de Penning ISOLTRAP au ISOLDE/CERN. Les nouveaux résultats sont inclus dans l’ajustement global et leurs influences sur les masses existantes sont discutées. La dernière partie de cette thèse porte sur les études des erreurs systématiques du spectromètre de masse à multi-réflexion à temps de vol d’ISOLTRAP, utilisant une source d’ions hors ligne et le faisceau de protons en ligne. A partir de l’analyse des mesures sélectionnées, j’ai trouvé que l’erreur systématique est beaucoup plus faible que les incertitudes statistiques obtenues jusqu’à présent.