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Nowadays it has become particularly valuable to control the Particulate Matter (PM) emissions from the road transport sector, especially in vehicle powertrains with an Internal Combustion Engine (ICE). However, almost no publication has focused on a comparison of the microscopic characteristics of gasoline and ethanol spray under injection pressure conditions of more than 30 MPa, except in the impingement process. By using a Phase Doppler Particles Analyser (PDPA) system, the microscopic characteristics of gasoline and ethanol spray from a Gasoline Direct Injection (GDI) injector under injection pressure ( P I ) up to 50 MPa was fully explored in this research. The experimental results demonstrate that under the same P I , the second peak of the probability ( p d ) curves of droplet normal velocity for gasoline is slightly higher than that of ethanol. Moreover, gasoline spray exceeds ethanol by about 5.4% regarding the average droplet tangential velocity at 50 mm of jet downstream. Compared to ethanol, the p d curve's peak of droplet diameter at (0, 50) for gasoline is 1.3 percentage points higher on average, and the overall Sauter mean diameter of gasoline spray is slightly smaller. By increasing P I from 10 MPa to 50 MPa, p d of the regions of "100 ≤ Weber number ( W e ) < 1000" and " W e ≥ 1000" increases by about 23%, and the p d of large droplets over 20 μm shows a significant reduction. This research would provide novel insights into the deeper understanding of the comparison between gasoline and ethanol spray in microscopic characteristics under ultra-high P I . Additionally, this research would help provide a theoretical framework and practical strategies to reduce PM emissions from passenger vehicles, which would significantly contribute to the protection and sustainability of the environment. [ABSTRACT FROM AUTHOR]

To improve the crushing efficiency and crushing pass rate of high-moisture corn ears (HMCEs), a multi-stage crushing scheme is proposed in this paper. A two-stage crushing device for HMCEs is designed, and the ear crushing process is analyzed. Firstly, a simulation model for HMCEs was established in EDEM software (2018), and the accuracy of the model was verified by the shear test. Subsequently, single-factor simulation experiments were conducted, with the crushing rate serving as the evaluation index. The optimal working parameter ranges for the HMCE device were identified as a primary crushing roller speed of 1200–1600 revolutions per minute (r/min), a secondary crushing roller clearance of 1.5–2.5 mm, and a secondary crushing roller speed of 2750–3750 r/min. A Box–Behnken experiment was conducted to establish a multiple regression equation. With the objective of maximizing the qualified crushing pass rate, the optimal combination of parameters was revealed: a primary crushing roller speed of 1500 r/min, a secondary crushing roller clearance of 2.5 mm, and a secondary crushing roller speed of 3280 r/min. The pass rate of corn cob crushing in the simulation test was 98.2%. The physical tests, using the optimized parameter combination, yielded a qualified crushing rate of 97.5%, which deviates by 0.7% from the simulation results, satisfying the requirement of a qualified crushing rate exceeding 95%. The experimental outcomes validate the rationality of the proposed crushing scheme and the accuracy of the model, providing a theoretical foundation for subsequent research endeavors. [ABSTRACT FROM AUTHOR]

The U.S. Food and Drug Administration (FDA) suggests the "Reference‐Scaled Average Bioequivalence" (RSABE) method in the average bioequivalence (ABE) study of highly variable drugs. The classic sample size estimation method for grouping sequential design (GSD) of the RSABE method is a single‐stage sample size multiplied by the inflation factor. This study proposed a new method for calculating the sample size for the GSD of the RSABE: using simulation experiments directly. In this work, our focal point is on a two‐stage GSD that adheres to the Pocock guideline, comprising a single interim analysis and a final analysis. We consider that the sample size of the two stages is equal; that is, the interim analysis is carried out at 50% of the information fraction. Extensive Monte Carlo simulations have shown that the new method is more accurate in estimating sample size than the inflation factor method, and the type I error rate is controlled below 5% in all conditions. In 90% power semireplicate studies, the average sample size required for the Pocock design is only 40% to 90% of the single‐stage design sample size. [ABSTRACT FROM AUTHOR]

Magnetic metals deposited on graphene hold the key to applications in spintronics. Here, we present the results of Fe islands grown on graphene/SiC(0001) by molecular beam epitaxy, which are investigated by scanning tunneling microscopy. The two types of islands distinguished by flat or round tops are revealed, indicating bimodal growth of Fe. The atomic structures on the top surfaces of flat islands are also clearly resolved. Our results may improve the understanding of the mechanisms of metals deposited on graphene and pave the way for future spintronic applications of Fe/graphene systems. [ABSTRACT FROM AUTHOR]

The reservoirs of ultra-deep and low-permeability sandstones typically exhibit characteristics of lithological tightness and poor physical properties. Fractures control the oil and gas content as well as the productivity of such reservoirs. However, the distribution of fractures is complex, exhibiting strong heterogeneity. Therefore, a systematic study on reservoir fracture modeling can provide geological foundations for the development of such reservoirs. Due to the considerable burial depth of these reservoirs, conventional methods relying solely on seismic information have limited reliability, and the established discrete network models of fractures are often less dependable. In this paper, taking the X gas reservoir in a basin in western China as an example, we discuss a fracture modeling method based on the integration of geological information to enhance the efficiency and accuracy of fracture modeling. The modeling method primarily involves the use of deterministic methods to obtain large-scale fractures, while random simulation is employed for small and medium-scale fractures. The fracture development control factors and seismic attribute information are integrated using permanence of ratios (PR) model to establish a fracture development probability field model. Subsequently, the geometric parameters of fractures and the fracture density model are used as input parameters to generate a discrete network model of small and medium-scale fractures using a object-based modeling method. Finally, based on the fracture equivalent property model and verified through geological understanding, analysis of production dynamics, and numerical simulation of the gas reservoir, it is demonstrated that the fracture model established using the proposed method aligns with geological understanding and exhibits high reliability. [ABSTRACT FROM AUTHOR]

The magnetically driven sample experiments which were carried out in an intense pulsed power device were simulated and analyzed by two-dimensional magnetically driven simulation code (MDSC2), and the structure coefficient of magnetically driven sample experiments was studied and analyzed. The numerical results show that MDSC2 can correctly simulate experiments of magnetically driven samples such as tin and magnesium-aluminum alloy. The simulated sample/window interface velocity (or flyer plate/window interface velocity) is basically consistent with the experimental measured one. The structure coefficients of magnetically driven samples are usually different when the magnetically driven sample experiments are different. The structure coefficient of magnetically driven sample experiment is related to the initial conditions such as the sample material and the width of the electrode plate but not to the initial thickness of the sample material. Under the same initial conditions, such as the thickness of the flyer plate, the material of the flyer plate, the material of the sample, the initial gap between the cathode and the anode, the wider the electrode plate, the larger the structure coefficient of the magnetic drive sample experiment. MDSC2 can correctly simulate the magnetically driven sample experiments, which makes MDSC2 an important tool for the study of magnetically driven sample experiments. [ABSTRACT FROM AUTHOR]

Keywords: electrochemical oxidation; benzylic C(sp 3)-H amidation; Ritter-type reaction; external mediator free; oxidant free; N -benzylamides EN electrochemical oxidation benzylic C(sp 3)-H amidation Ritter-type reaction external mediator free oxidant free N -benzylamides 2969 2978 10 08/31/23 20230915 NES 230915 Graph Amides are abundant in almost all living organisms, and the amide group is one of the most common and versatile functional groups in a number of peptides and proteins, [1] pharmaceuticals, [2] agrochemicals, [3] and fluorescent sensor, [6] etc. Electrochemical Benzylic C(sp3)-H Amidation via Ritter-Type Reaction in the Absence of External Mediator and Oxidant N -(1-(4'-Ethyl-[1,1'-biphenyl]-4-yl)ethyl)acetamide (3c) The product was purified by silica gel column chromatography with PE/EtOAc (1:1, v/v); white solid; yield: 61.5 mg (77%); mp 144-146 °C. N -(1-(4'-Methyl-[1,1'-biphenyl]-4-yl)ethyl)acetamide (3b) The product was purified by silica gel column chromatography with PE/EtOAc (1:1, v/v); white solid; yield: 59.1 mg (78%); mp 160-162 °C. [Extracted from the article]

Pulsed power technology, whereas the electrical energy stored in a relative long period is released in much shorter timescale, is an efficient method to create high energy density physics (HEDP) conditions in laboratory. Around the beginning of this century, China Academy of Engineering Physics (CAEP) began to build some experimental facilities for HEDP investigations, among which the Primary Test Stand (PTS), a multi-module pulsed power facility with a nominal current of 10 MA and a current rising time ∼90 ns, is an important achievement on the roadmap of the electro-magnetically driven inertial confinement fusion (ICF) researches. PTS is the first pulsed power facility beyond 10 TW in China. Therefore, all the technologies have to be demonstrated, and all the engineering issues have to be overcome. In this article, the research outline, key technologies and the preliminary HEDP experiments are reviewed. Prospects on HEDP research on PTS and pulsed power development for the next step are also discussed.

In the past decade, the rapid development of modern heterointerface growth and characterization techniques has stimulated great effort to research and design the extraordinary physical properties of transition metal heterostructure composite materials. Here, new physics originates from the rearrangement of orbital, charge, spin, and lattice and the resulting rebalancing of their mutual interactions. In this paper, recent experimental and theoretical progress in the design, preparation, characterization, and physical property measurement of LaNiO3‐based heterostructure composites and the infinite‐layer Ni1 + nickelate superconducting thin films on (001) SrTiO3 substrate is reviewed, mainly by the methods of various X‐ray spectroscopy measurements, scanning transmission electron microscopy, and magneto‐transport measurements. In these materials, the electronic structure and orbital occupation around the Fermi level are modified, enabling nickelate‐based composite materials to exhibit new states of matter and physical phenomena, which are absent in the bulk constituents. Their confined structures, superconductivity, orbital polarization, charge transfer, electronic structures, magnetic properties, and X‐ray spectroscopic analysis, are therefore highlighted, aiming at understanding unconventional superconducting mechanisms and designing new high‐Tc superconducting low‐dimensional materials for device applications. [ABSTRACT FROM AUTHOR]