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Quantum Dot Cellular Automata (QCA) and reversible logic have emerged as promising alternatives to conventional CMOS technology, offering several advantages, such as ultra-dense structures and ultra-low-power consumption. Among the crucial components of processors, the Arithmetic Logic Unit (ALU) has witnessed significant advancements in reversible computing, leading to energy-efficient and high-speed computing systems, particularly beneficial for Digital Signal Processing (DSP) applications. Conventional ALUs, reliant on irreversible logic, encounter energy inefficiencies due to information loss during computations, resulting in increased power consumption. Moreover, they may face limitations in processing speed, impacting real-time processing capabilities, especially for complex DSP tasks involving intensive arithmetic and logic operations. In response to these challenges, a research paper presents a pioneering approach, proposing a novel reversible ALU design using QCA nanotechnology. The proposed design ingeniously incorporates Modified Fredkin (MF) gates, and a coplanar reversible full adder based on the HNG gate, skillfully leveraging the unique features of QCA nanotechnology to optimize the ALU's energy-efficient and high-speed performance for DSP applications. This revolutionary QCA reversible ALU comprises 330 QCA cells arranged in a compact 0.41 μm2 area, skillfully realized through the coplanar clock-zone-based crossover approach. Its core computational elements, the three MF gates, and the innovative coplanar reversible full adder empower the ALU to execute a remarkable array of 20 distinct arithmetic and logic operations, showcasing its versatility in handling diverse DSP tasks. The proposed structure undergoes extensive simulations utilizing QCADesigner version 2.0.3 to confirm its performance. The evaluation results manifest substantial improvements compared to previous designs, boasting a 30% reduction in area occupancy, a 20% decrement in cell count, a 10% reduction in latency, and a 10% decrease in quantum cost compared to the best-known previous structure. These compelling outcomes solidify the potential of the proposed reversible ALU as a transformative advancement in energy-efficient and high-speed computing for DSP applications. [ABSTRACT FROM AUTHOR]

China shale oil, which is preserved in lacustrine shale with strong heterogeneity and relatively low maturity, has been a research hotspot of unconventional resources. However, controlling factors of shale oil enrichment and resource potential evaluation restricted efficient exploration and development of lacustrine shale oil. On the basis of well logging data, TOC content, Rock-Eval pyrolysis values, thermal maturity, 100 oil saturation data, and pressure coefficient, the core observation, X-ray diffraction analysis, physical property analysis, scanning electron microscopy, CT scan, well logging interpretation, and volumetric genesis method depending on three-dimensional geological modeling were used to determine enrichment factors and evaluate the resource potential of Qingshankou Formation shale oil in the Southern Songliao Basin. Shale oil was mainly enriched in the semideep and deep lake shale of K2qn1, with the high capacity of hydrocarbon generation and favorable petrological and mineralogical characteristics, pore space characteristics, and physical properties in the low structural part of the Southern Songliao Basin. The three-dimensional geological resource model of Qingshankou Formation lacustrine shale oil was determined by the key parameters (Ro, TOC, and S 1 ) of shale oil in the favorable zone of the Southern Songliao Basin, northeast China. The geological resource of shale oil, which was calculated by two grid computing methods ( F 1 and F 2 ), was, respectively, 1.713 × 10 12 kg and 1.654 × 10 12 kg. The great shale oil resource indicates a promising future in the exploration and development of Qingshankou Formation shale oil of the Southern Songliao Basin. [ABSTRACT FROM AUTHOR]

China shale oil, which is preserved in lacustrine shale with strong heterogeneity and relatively low maturity, has been a research hotspot of unconventional resources. However, controlling factors of shale oil enrichment and resource potential evaluation restricted efficient exploration and development of lacustrine shale oil. On the basis of well logging data, TOC content, Rock-Eval pyrolysis values, thermal maturity, 100 oil saturation data, and pressure coefficient, the core observation, X-ray diffraction analysis, physical property analysis, scanning electron microscopy, CT scan, well logging interpretation, and volumetric genesis method depending on three-dimensional geological modeling were used to determine enrichment factors and evaluate the resource potential of Qingshankou Formation shale oil in the Southern Songliao Basin. Shale oil was mainly enriched in the semideep and deep lake shale of K2qn1, with the high capacity of hydrocarbon generation and favorable petrological and mineralogical characteristics, pore space characteristics, and physical properties in the low structural part of the Southern Songliao Basin. The three-dimensional geological resource model of Qingshankou Formation lacustrine shale oil was determined by the key parameters (Ro, TOC, and S 1 ) of shale oil in the favorable zone of the Southern Songliao Basin, northeast China. The geological resource of shale oil, which was calculated by two grid computing methods ( F 1 and F 2 ), was, respectively, 1.713 × 10 12 kg and 1.654 × 10 12 kg. The great shale oil resource indicates a promising future in the exploration and development of Qingshankou Formation shale oil of the Southern Songliao Basin. [ABSTRACT FROM AUTHOR]

Permeability heterogeneity of tight sandstone reservoir is mainly determined by the types and quantities of different cements and dissolution processes that occur during the burial. The thin section description, scanning electron microscopy (SEM), x-ray diffraction (XRD), cathodoluminescence imaging (CL), computed tomography (CT) scans, mercury intrusion tests, electron probe analysis, fluid inclusions and isotopic analysis were used to determine genetic mechanism and its impact on reservoir quality of differential cement combinations in Shaximiao Formation tight sandstone in the Central Sichuan Basin, China. Diagenetic minerals in the Shaximiao Formation (J 2 s) sandstone comprise calcite, laumontite, chlorite and dissolution. The pore space of J 2 s sandstone mainly comprises primary pores and secondary pores formed after mineral dissolution. The reservoir sandstones can be divided into six types according to different combinations of the laumontite, chlorite and calcite. Authigenic chlorite coating of J 2 s sandstones occurred via chloritization of smectite during eodiagenesis. Laumontite cements derived from transformation of volcanic rock fragments, were precipitated in a strong alkaline environment with high pH value (9.5–12) and abundant Ca2+, Si4+, Al3+ during eodiagenesis. The δ13C and δ18O isotopic values and petrological characteristics indicate that calcite cement was related to feldspar dissolution and decarboxylation of organic matter. The different cement combinations were determined mainly by the sedimentary facies and subsequent diagenetic environment evolution. Laumontite precipitation needs a stronger alkaline diagenetic environment than that for chlorite and calcite. The early chlorite coating provided sufficient remaining pore-space for pore-filling laumontite and calcite precipitation. The presence of pore-filling laumontite decreased space for calcite precipitation. However, laumontite is more readily soluble than calcite. The different cement combinations have distinct residual pore space combinations meaning that some intervals of rock have sufficient permeability to act as viable reservoir rock whilst other combinations do not. • Laumontite-chlorite -calcite system can be divided into six combination types. • Cements combinations were determined by sedimentary facies and diagenetic evolution. • Differential precipitation of cements produces strong sandstone heterogeneity. [ABSTRACT FROM AUTHOR]

The dolostone reservoir of the Middle Permian Maokou Formation in Eastern Sichuan has good prospects for oil and gas exploration. Study of dolomitizing genesis of the Maokou Formation is essential for predicting the distribution of the dolostone reservoir. Petrography, in situ geochemistry, Sr-Mg isotopes, and fluid inclusions were carried out on samples from the Maokou Formation in Eastern Sichuan in order to discuss the dolomitizing process. Based on mineral and textural characteristics, dolomites were divided into four components: partially clouded dolomite (PCD), mosaic-like dolomite (MLD), cloudy-centered and clear-rimmed dolomite (CACD), and saddle dolomite (SDD). Results indicate that the Maokou Formation in Eastern Sichuan mainly experienced two stages of dolomitization. PCD, MLD, and cloudy-centered dolomite (CCD) were formed during the early dolomitization. They all show turbid crystal planes and bright orange-red CL and have similar trace element contents, 87Sr/86Sr ratios, and rare-earth patterns, indicating that they might be formed in the same fluid. This is a period when dolomitizing fluids mainly migrated along pores or microcracks and replaced protogenetic calcites, which occurred in the shallow burial stage of the Maokou Formation before the Late Permian. Clear-rimmed dolomite (CRD) and SDD were formed in the late stage of dolomitization. They all have clean crystal planes and darkly red CL. CRD of the ERY profile has trace element contents, 87Sr/86Sr ratios, and rare-earth patterns similar to SDD of the HLCH profile and Well TL6, inferring that both may be formed in the same fluid. Combined with high SrO contents and homogenous temperatures of fluid inclusions of CRD and SDD and Mg-isotopic compositions, they were generated by hydrothermal dolomitization. The hydrothermal fluid stage is related to the movement of the Emeishan Large Igneous Province, which was made up of basaltic magmatic fluids mixing with the surface water. The hydrothermal fluid mainly migrated upwards along structural fractures or faults and filled in structural fractures, occurring in the Late Permian to Middle-Late Triassic. [ABSTRACT FROM AUTHOR]

• Fabrication and characterization of a novel MnTMPyP/TaMoO 6 nanocomposite were performed for the first time. • The simultaneous determination of DA and AA at MnTMPyP/TaMoO 6 was performed, and it has a low detection limit. • MnTMPyP/TaMoO 6 nanocomposite has satisfactory stability, good reproducibility and strong anti-interference property. • The performance of MnTMPyP/TaMoO 6 nanocomposite for AA and DA in actual samples was evaluated. [Display omitted] A novel highly selective nanocomposite MnTMPyP/TaMoO 6 was successfully synthesized and developed for simultaneous detection of Ascorbic acid (AA) and dopamine (DA). Firstly, the host material LiTaMoO 6 was synthesized by the high temperature solid phase method. After the exfoliation/restacking process of the host material, the nanocomposite was formed through electrostatic self-assembly. The structure and morphology were characterized using X-ray diffraction (XRD), scanning electron microscope (SEM), transmission electron microscope (TEM), energy dispersive spectrometer analysis (EDS), ultraviolet-visible (UV–vis) and Fourier transform infrared spectrometer (FTIR). And the electrochemical behaviors of the modified electrode were further explored by cyclic voltammetry (CV), electrochemical impedance analysis (EIS), and differential pulse voltammetry (DPV). Under the optimal conditions, the MnTMPyP/TaMoO 6 provides a high sensitivity and selectivity in detecting AA and DA with linear response ranges of 12–674 μM. The resulting detection limit is also calculated as 0.97 and 0.54 μM, respectively. In addition, the MnTMPyP/TaMoO 6 nanocomposite exhibits excellent stability, reproducibility, and good anti-interference. [ABSTRACT FROM AUTHOR]