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DarkSide-50 at Gran Sasso underground laboratory (LNGS), Italy, is a direct dark matter search experiment based on a liquid argon TPC. DS-50 has completed its first dark matter run using atmospheric argon as target. The detector performances and the results of the first physics run are presented in this proceeding.

High-speed on/off valve, an important part of turbocharging system, its quick response has a direct impact on the turbocharger pressure cycle. The methods of improving the response characteristic of high speed on/off valve include increasing the magnetic force of armature and the voltage, decreasing the mass and current of coil. The less coil number of turns, the solenoid force is smaller. The special armature structure and the magnetic material will raise cost. In this paper a new scheme of double voltage driving circuit is investigated, in which the original driving circuit of high-speed on/off valve is replaced by double voltage driving circuit. The detailed theoretical analysis and simulations were carried out on the double voltage driving circuit, it showed that the switching time and delay time of the valve respectively are 3.3ms, 5.3ms, 1.9ms and 1.8ms. When it is driven by the double voltage driving circuit, the switching time and delay time of this valve are reduced, optimizing its response characteristic. By the comparison related factors (such as duty cycle or working frequency) about influences on response characteristic, the superior of double voltage driving circuit has been further confirmed.

Tool wear/tool life is an important aspect commonly considered in evaluating the performance of a machining process. The advent of new grooved tools with complex chip-groove geometry has required a better understanding of their effects on tool wear/tool life. This paper presents an overview of research at the University of Kentucky on extensions to the conventional tool wear and tool life methodologies when machining with grooved tool inserts resulting from the more complex wear features observed and the more subtle failure criteria applied. The influence of cutting conditions including the cutting speed, feed and depth of cut on the tool life was studied experimentally using tools with chip-groove geometries and different tool coatings. It was shown that the slope and intercept of the log-log plot of tool life versus feed, for example, change considerably for different chip-groove geometries or different tool coatings. An empirical tool-life equation to consider the effects of these parameters was proposed. The approach described required that 11 tool wear/tool life tests be conducted for every tool insert. In a comparison between predicted and experimental tests involving 200 production trials, this approach predicted tool life within 24% of the results encountered, while tool-life estimations using conventional approaches yielded results that gave an error of more than 300%. Furthermore, an ‘equivalent toolface (ET)’ model was developed to correlate progressive tool wear to changes in chip formation with corresponding predictability of the dominant wear modes in turning with grooved cutting tools.

Based on the behavior of carbon steel outlet tube in REAC pipes of Zhenhai Refining & Chemical Company, the mathematical model of fluid-solid interaction was established according to the mechanism of erosion-corrosion damage. The interaction between corrosion products protecting film and multiphase liquid was analyzed by numerical simulation method. The distribution of shearing stress on the inwall of elbow bend, and the distribution of principal displacement, stress and strain of corrosion products protecting film were disclosed, while the erosion-corrosion failure processes was studied. The simulation result coincides with that of the positioned thickness gauging which validated the reliability and feasibility of the finite element analysis software simulation method. The obtained results can be used in the erosion-corrosion failure analysis, structural optimization, in-service testing positioning, life prediction, risk assessment, safety and other security projects for multiphase flow pipeline.

An in-line slit-die viscometer (SDV) was used to measure the viscosity of a melt extrudate independently of the extruder operating conditions. The melt produced by extrusion of the corn grits followed a power law rheological model. The viscosity of the melt and extrusion parameters such as specific mechanical energy (SME), torque, and die pressure decreased with increasing moisture content. The degree of starch gelatinization increased when barrel temperature increased from 90 to 130 degrees C. At temperatures higher than 130 degrees C, most of the starch had gelatinized. The increase in barrel temperature, however, resulted in small changes in the apparent viscosity of the melt, until a maximum of approximately equal to 130 degrees C. At a constant feed rate, SME increased and torque decreased when screw speed increased due to the shear thinning behavior of the melt. At a constant screw speed, the torque increased and SME decreased with increasing feed rate. This was due to a decrease in apparent viscosity of the melt at higher feed rates. SME is not an independent extrusion variable and should be used with caution either when predicting the effect of thermomechanical treatment of the product or as the key and only variable for controlling the food extrusion process.

Recent studies have found that the core–shell structured metal nanoparticles and porous carbon nanofibers (PCNF) are combined into a microwave absorbing material through electrospinning, which exhibits excellent microwave absorption performance. In this study, the core–shell structure Co nanoparticles prepared by the self-developed HEIBE process (production rate of > 50 g/h) were combined with porous carbon fibers, and their absorbing properties were greatly improved. The morphology of Co/PCNF demonstrated that CoNPs are randomly dispersed in the porous carbon nanofibers and carbon nanofiber form complex conductive network which enhances the dielectric loss of the materials. Meanwhile, the Co/PCNF has a low graphitization and shows a significant improvement in permittivity due to the combination of CoNPs and high conductivity of carbon material. The maximum reflection loss (RL) of Co/PCNF reaches − 63.69 dB at 5.28 GHz with a thickness of 5.21 mm and the absorption bandwidth (RL ≤  − 10.0 dB) is 12.92 GHz. In terms of 5.60 mm and 6.61 mm absorber, there are two absorption peaks of − 47.64 dB and − 48.30 dB appear around 12.50 GHz and 14.10 GHz, respectively. The results presented in this paper may pave a way for promising applications of lightweight and high-efficiency microwave absorbing materials (MAMs).

Circular electron positron colliders, such as the CEPC and FCC-ee, have been proposed to measure Higgs boson properties precisely, test the Standard Model, search for physics beyond the Standard Model, and so on. One of the important goals of these colliders is to measure the W boson mass with great precision by taking data around the W -pair production threshold. In this paper, the data-taking scheme is investigated to maximize the achievable precisions of the W boson mass and width with a threshold scan, when various systematic uncertainties are taken into account. The study shows that an optimal and realistic data-taking scheme is to collect data at three center-of-mass energies and that precisions of 1.0 MeV and 3.4 MeV can be achieved for the mass and width of the W boson, respectively, with a total integrated luminosity of L = 3.2  ab - 1 and several assumptions of the systematic uncertainty sources.

Salt stress in plants presents a major challenge to future agricultural production. Digestate has various effects on plant growth, but little information is available on its effects on the antioxidant system and physiological characteristics of lettuce under salt stress. In this study, the impacts of mineral fertilizer and digestate application on edible parts of lettuce were compared under three salinities. Experimental treatments comprised application of two types of fertilizer (mineral fertilizer and digestate) and three NaCl concentrations (0, 3, and 7.5 dS m − 1 ). High NaCl concentrations resulted in significantly lower photosynthesis, growth, and physiological indices compared with those under no NaCl addition. However, under the 7.5 dS m − 1 NaCl condition, digestate application (DA) increased the fresh weight (42%), dry weight (27%), photosynthetic pigment contents and photosynthesis (20%) of lettuce compared with that under mineral fertilizer application (MFA). Accumulation of reactive oxygen species was markedly lower, and the membrane stability index was therefore higher, under DA compared with under MFA within the same salinity level. Lipid peroxidation was lower under DA compared with under MFA in all salinity treatments. Salt stress up-regulated the antioxidant system and DA further increased the enzymatic and non-enzymatic antioxidant capability compared with that under MFA. In addition, the total water use was lower and water-related indices, such as water use efficiency of fresh weight, water use efficiency of dry weight and relative water content, were higher under DA compared with under MFA. The application of digestate instead of mineral fertilizer could be a promising practice to alleviate the negative impact of salt stress on the productivity and physiological characteristics of lettuce plants.

In the context of the economic globalization, there is an increased disruption risk in the supply chain network due to the outsourcing, complexity and uncertainty. At the same time, the disruption may propagate across the entire supply chain network because of the interdependence. With the resource constraints, appropriate recovery strategies which can minimize the impact of disruption propagation and effectively improve the supply chain network resilience have attracted a great deal of attention. In this paper, we first construct the disruption propagation model considering the recovery strategy based on the characteristics of the competitiveness, time delay and underload cascading failure in the supply chain network. This model uses the memetic algorithm to determine the set of recovery nodes among all disruption nodes, which can minimize the impact of disruption propagation. And then, the simulation analysis is conducted on the synthetic network and the real-world supply chain network. We compare the proposed recovery strategy with other strategies (according to the genetic algorithm, according to the descending order of the load of failure node, according to the ascending order of the load of failure node, according to the descending order of the node degree, according to the ascending order of the node degree) and provide decision-making reference against supply chain disruptions.

A 500-kg 27SiMn steel ingot has been produced via low-oxygen purifying technology and then fully dissected in the longitudinal center plane to investigate the typical features and formation mechanism of A-segregates. The macrostructure, microstructure, inclusions, cavity and solute segregation surrounding the A-segregates were characterized and analyzed in detail. It shows that the main solute components such as C, Si, and Mn, and even some large cavities accumulate obviously within the A-type channels. Owing to the low content of oxygen and other impurities, there is no apparent enrichment of the inclusions. Based on the classical theory of macrosegregation, driven by thermo-solutal buoyancy, A-segregates in the body of a 27SiMn steel ingot have been simulated successfully by using the multi-component continuum model. They disappear in a referred 1045 steel ingot. By comparing the evolution processes during solidification of both steels, it is demonstrated that the strong thermo-solutal convection originated from the high content of Si element in 27SiMn steel destabilizes the mushy zone and therefore induces the A-segregates. In terms of the occurrence zones of A-segregates and corresponding distributions of Rayleigh number, its critical value to predict the A-segregates in industrial steel ingots was proposed and then applied successfully.