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The separation of aromatic hydrocarbons from straight-run naphtha is crucial for the optimal utilization of naphtha resources in the petrochemical industry. Bimetallic halides exhibit excellent performance in aromatic separation from straight-run naphtha. Therefore, it is highly significant to investigate the complexation mechanism and aromatic separation mechanism for bimetallic halide selection and further separation performance enhancement. In this study, CuAlCl4and Sn(AlCl4)2were used in the separation of aromatics from naphtha and exhibited excellent performance. The complexation mechanism of bimetallic halide-aromatic complexes was elucidated by XAFS, FT-IR, and density functional theory. The results unveiled that bimetallic halides could coordinate with only one aromatic ring. The geometric structures, bonding characteristics, and weak interaction between bimetallic halides and hydrocarbons were analyzed by a series of wavefunction analysis methods. The results indicated that there was π complexation between bimetallic halides and aromatics, in which s and d orbitals of Cu(I) ion and s and p orbitals of Sn(II) ion played an important role. Meanwhile, there was weak hydrogen bonding interaction between bimetallic halides and aliphatic hydrocarbons. The directional complexation between bimetallic halides and aromatics was the essential reason for aromatic separation.

Effective clinical practice of precise photodynamic therapy (PDT) is severely impeded by the inherent drawbacks and aggregation propensity of conventional photosensitizers. An all-in-one approach is highly desired to optimize structural features, photophysical properties, and pharmacokinetic behaviors of photosensitizers. Herein, we have fabricated mesoporous boron dipyrromethene-bridged coordination polymer nanophotosensitizers (BCP-NPs) for high-performance PDT via a unique solvent-assisted assembly strategy. Distinctive photophysical and structural characteristics of BCP-NPs confer enhanced photodynamic activities, together with high cellular uptake and ultrahigh stability. Moreover, BCP-NPs showed excellent tumor accumulation and prolonged tumor retention, achieving eradication of the triple-negative breast cancer (TNBC) model under low-power-density LED irradiation. This work has provided a valuable paradigm for the construction of mesoporous photoactive nanomaterials for biophotonic applications.

The CO2methanation reaction, which achieves the carbon cycle and gains value-added chemicals, has attracted much attention, but the design and exploitation of highly active catalysts remain a big challenge. Herein, zirconium dioxide-supported Ni catalysts toward low-temperature CO2methanation are obtained via structural topological transformation of NiZrAl-layered double hydroxide (LDH) precursors, which have the feature of an interfacial structure (Ni–O–Zr3+–Vö) between Ni nanoparticles and ZrO2–xsupport (0 < x< 1). The optimized catalyst (Ni/ZrO2–x-S2) exhibits exceptional CO2conversion (∼72%) at a temperature as low as 230 °C with a ∼100% selectivity to CH4, without obvious catalyst deactivation within a 110 h reaction at a high gas hourly space velocity of 30,000 mL·g–1·h–1. Markedly, the space–time yield of CH4reaches up to ∼0.17 molCH4·gcat–1·h–1, which is superior to previously reported Ni catalysts evaluated under similar reaction conditions. Both in situ/operando investigations (diffuse reflectance infrared Fourier transform spectroscopy and X-ray absorption fine structure) and catalytic evaluations substantiate the interfacial synergistic catalysis at the Ni/ZrO2–xinterface: the Zr3+–Vö facilitates the activation adsorption of CO2, while the H2molecule experiences dissociation at the metallic Ni sites. This work demonstrates that the metal–support interface effect plays a key role in improving the catalytic behavior toward CO2methanation, which can be extended to other high-performance heterogeneous catalysts toward structure-sensitive systems.

It is of great significance to reveal the influence on the output performance of pneumatic hammers under different drilling condition parameters to improve their impact efficiency used in drilling applications. In this study, Computational fluid dynamics (CFD) wisth dynamic mesh method was utilized to simulate dynamic airflow and piston movement within the hammer. User-Defined Functions (UDFs) are modified to introduce friction and varying well deviation angles. Meanwhile, a test bench of pneumatic hammer performance is designed and built to record real-time data on the piston displacement and chamber pressure within the hammer, validating the simulation results. The results show that the simulated and experimental data exhibit similar values and trends, with a maximum error of 10.92% for the impact velocity, 9.5% for the impact frequency, 8.36% for the maximum piston displacement, and 10.81% for the pressure drop, respectively. In addition, the piston motion mechanism was analyzed and the effects of well deviation angle, mass-flow rate, backpressure, restitution coefficient, and friction coefficient on the hammer's performance were investigated in detail. The results indicate that the mass-flow rate and restitution coefficient have a positive effect on increasing the piston's impact velocity and impact frequency, as well as pressure drop. In the context of directional drilling, the hammer's impact energy varies with the well deviation angle. At lower values of the friction coefficient, a clear positive correlation emerges between impact energy and deviation angle. Conversely, at larger values of the friction coefficient, a distinct biphasic behavior is observed, with the impact energy first decreasing before subsequently increasing. Furthermore, the backpressure, and friction coefficient adversely affect the hammer performance, with the backpressure being the dominant factor.

Bimetallic composite ionic liquids (ILs) show outstanding performance in catalysis and material fields. The unambiguous identifications of their structures are fundamental to understanding the unique catalysis mechanism. CuCl and ZrCl4were selected for their higher solubilities in [BMIM]Cl-xAlCl3ILs, which suggested a greater likelihood of abounding bimetallic complexes. The solubility of CuCl and ZrCl4in ILs both reached a maximum with the increase of the AlCl3/[BMIM]Cl molar ratio, with the maximum appearing at 1:1.60:0.40 and 1:1.40:0.43 (molar ratio), respectively. The X-ray absorption fine structure (XAFS) measurements recognized bimetallic complex anions [AlCuCl5]−and [Al2ZrCl11]−, which were connected by halogen bridges. Additionally, the changes in coordination affinity for composition-varied ILs reflected by XAFS accounted for the solubility trends. The three-dimensional structure information of the bimetallic composite species was revealed by density functional theory (DFT) calculation. Monodentate [AlCl4]−ligands appeared in [BMIM][AlCuCl5], whereas bidentate coordination was found in [BMIM][Al2ZrCl11] with seven coordinated zirconium. To elucidate the speciations and the formation mechanism, thermodynamic behaviors for aggregation processes of clusters [BMIM][AlxCuyClz] and [BMIM][AlxZrqClz] (x, y, q= 1–2, z= 5,8,9,11,15) were analyzed. The formation of [BMIM][AlCuCl5] and [BMIM][Al2ZrCl11] acted most exothermically in thermodynamics (−28.37 and −10.45 kcal/mol), indicating the most stable bimetallic composite species.

The deep ice cores preserved within the polar ice sheets hold a wealth of valuable information, and the demand for ice cores in related scientific research is on the rise. Thus, the replication of ice cores from the borehole wall holds significant importance. However, current methods face limitations such as difficulties in whipstock retrieval, extended auxiliary working hours, structural complexity, and the necessity of ice core depth calibration. To address this, this study proposes a novel method for replicating ice cores from the borehole wall utilizing a thermal coring drill bit. The design and dynamic analysis of the scissor deployable mechanism employed to drive the drill bit movement were thoroughly examined through theoretical and simulation studies. The motion characteristics of the drill bit during the replication coring process and the stress–strain behavior of the scissor rods were determined and validated through drill bit movement experiments, demonstrating a maximum error of 10%. The findings reveal that the mechanism can meet the strength requirements across three operating stages: horizontal drilling, vertical coring, and ice core recovery, with maximum loads of approximately 284 N, 749 N, and 970 N, respectively. Increasing the thickness of the scissor rods and reducing their length can augment the load-bearing capacity of the structure. Additionally, the speed transmission characteristics derived from the scissor mechanism can offer theoretical support for the drill's control system.

Utilizing the Geneva drive mechanism, an inventive retractable drill bit tailored for casing-while-drilling (CwD) applications was developed. This novel design allows the lower segment of the drill bit to be swung outward through rotation, facilitating to drill a larger hole and retrieved effortlessly by raising the drill tools. An exploration into the dynamic behavior of this retractable drill bit under varying drilling conditions was undertaken, focusing on parameters such as weight-on-bit, rotation speed, friction coefficient between the drill bit and rock, and lifting force. Findings from the investigation revealed that, under conditions of 20 kN weight-on-bit, a friction coefficient of 0.3, and a rotation speed of 30 rpm, the drill bit achieved full extension within 3.8 s. Notably, the movement speed of the lower drill bit was notably influenced by weight-on-bit, the friction coefficient, and lifting force, demonstrating accelerated movement with increased values of these factors. Rotation speed, however, exhibited negligible impact on the movement of the drill bit. An indoor experimental examination mirrored the outcomes obtained through simulations. Subsequent to numerical simulations and indoor testing, a large-diameter drill bit was produced and field tested, showcasing its capability to flexibly extend and retract during drilling, achieving an average drilling speed of 1.7 m/h.

Selective hydrogenolysis of biomass-derived glycerol to 1,2-propanediol (1,2-PDO) is a significant reaction for the production of high value-added chemicals, in which design and preparation of high-performance heterogeneous catalysts remain a big challenge. Herein, we report a PtIn alloy catalyst with a tunable electronic and geometric structure, confirmed by several elaborate characterizations including high-resolution transmission electron microscopy, in situCO-DRIFTS, quasi in situX-ray photoelectron spectroscopy, and in situX-ray absorption fine structure (XAFS) analysis. As expected, the PtIn-2 catalyst exhibits remarkably enhanced catalytic behavior for glycerol hydrogenolysis to 1,2-PDO (conversion: 99.8%; selectivity: 91.1%) with a turnover frequency value of 222 h–1, much larger than that of a pristine Pt catalyst and among the highest level of those of the reported Pt-based catalysts under mild reaction conditions (200 °C, 2.0 MPa). Furthermore, both in situstudies (in situglycerol-XAFS and in situglycerol-DRIFTS) and catalytic evaluations verify that the PtIn alloy structure contributes to the dramatically improved catalytic performance: the Ptδ−site at the Pt–In alloy interface serving as the intrinsic catalytic active center improves the activation and breakage of α-C–H and bonded hydroxyl groups in glycerol molecules, while the discrete Pt sites suppress the C–C bond cleavage. Consequently, the alloying effect changes the catalytic active center and promotes the rate-determining step (the formation of intermediate glyceraldehyde) in contrast to the traditional monometallic Pt catalyst. Our study demonstrates a successful paradigm in the design of highly efficient Pt-based catalysts by virtue of alloying, which would inspire more explorations on other noble metal systems.

A chromosome segment substitution line (CSSL) is a powerful tool for combining quantitative trait locus (QTL) mapping with the pyramiding of desirable alleles. The rice CSSL Z1364 with increased kernel number was identified in a BC3F8population derived from a cross of Nipponbare as the recipient with Xihui 18 as the donor parent. Z1364 carried three substitution segments distributed on chromosomes 1, 6, and 8. The mean substitution length was 1.19 Mb. Of 17 QTL identified on the substitution segments, qSP1for spikelets per panicle, qSSD1for seed-set density, and qNSB1for number of secondary branches explained respectively 57.34%, 87.7%, and 49.44% of the corresponding phenotypic variance and were all linked to RM6777. Chi-square analysis showed that the increased kernel number in Z1364 was inherited recessively by a single gene. By fine mapping, qSP1was delimited to a 50-kb region on the short arm of chromosome 1. Based on DNA sequence, a previously uncharacterized rice homolog of Arabidopsis thaliana AT4G32551was identified as a candidate gene for qSP1in which mutation increases the number of spikelets and kernels in Z1364. qSP1was expressed in all tissues, but particularly in 1-cm panicles. The expression levels of OsMADS22, GN1A, and DSTwere upregulated and those of LAX2, GNP1, and GHD7were downregulated in Nipponbare. These results provide a foundation for functional research on qSP1.

Ruthenium-based catalysts are one of the most promising candidates toward selective hydrogenation of benzene. In this work, we synthesized a novel core–shell catalyst by coating porous B-doped ZrO2on the surface of Ru/ZrO2particles (denoted as Ru/ZrO2@ZrO2-B(x%)), in which the hydrogen dissociation occurs on the inner surface of metal Ru and the acid site of the exterior ZrO2-B(x%) serves as the adsorption site for benzene. The Ru/ZrO2@ZrO2-B(5%) sample demonstrates the optimal synergistic catalysis between metal Ru and the weak/medium-strong Lewis acid site of the ZrO2-B(5%) layer, which promotes the activated adsorption of benzene and desorption of cyclohexene. Therefore, it exhibits the best catalytic performance (benzene conversion: 53.1%; cyclohexene selectivity: 58.8%) without using any additives.