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The high-precision magnetic survey system is crucial for ocean exploration. However, most existing systems face challenges such as high noise levels, low sensitivity, and inadequate magnetic compensation effects. To address these issues, we developed a high-precision magnetic survey system based on the manned submersible "Deep Sea Warrior" for deep-ocean magnetic exploration. This system incorporates a compact optically pumped cesium (Cs) magnetometer sensor to measure the total strength of the external magnetic field. Additionally, a magnetic compensation sensor is included at the front end to measure real-time attitude changes of the platform. The measured data are then transmitted to a magnetic signal processor, where an algorithm compensates for the platform's magnetic interference. We also designed a deep pressure chamber to allow for a maximum working depth of 4500 m. Experiments conducted in both indoor and field environments verified the performance of the proposed magnetic survey system. The results showed that the system's sensitivity is ≤0.5 nT, the noise level of the magnetometer sensor is ≤1 pT/√Hz at 1 Hz, and the sampling rate is 10 Hz. The proposed system has potential applications in ocean and geophysical exploration. [ABSTRACT FROM AUTHOR]

High-precision magnetometers play a crucial role in ocean exploration, geophysical prospecting, and military and security applications. Installing them on human-occupied vehicle (HOV) platforms can greatly enhance ocean exploration capabilities and efficiency. However, most existing magnetometers suffer from low sensitivity and excessively large size. This study presents a high-sensitivity, miniaturized magnetometer based on cesium optically pumped probes. The designed magnetometer utilizes a three-probe design to eliminate the detection dead zone of the cesium optically pumped probe and enable three-dimensional magnetic detection. The proposed magnetometer uses a flux gate probe to detect the three-axis magnetic field and ensure that the probe does not enter the dead zone. The three probes can automatically switch by measuring the geomagnetic elements and real-time attitude of the HOV platform. This article primarily introduces the cesium three-probe optically pump, flux gate sensor, and automatic switching scheme design of the above-mentioned magnetometer. Moreover, it is proven through testing that the core indicators, such as the accuracy and sensitivity of the cesium three-probe optically pumped and flux gate sensor, reach international standards. Finally, the effectiveness of the automatic switching scheme proposed in this study is demonstrated through drone-mounted experiments. [ABSTRACT FROM AUTHOR]

Deep coalbed methane (DCBM) reservoirs hold exceptional potential for diversifying energy sources. The Ordos Basin has attracted much attention due to its enormous resource reserves of DCBM. This work focuses on the Jiaxian area of the Ordos basin, and the multi-factor quantitative evaluation method on the sealing of cap rocks is established. The abundant geologic and reservoir information is synthesized to explore variable factors affecting the gas content. Results indicate that the sealing capacity of the coal seam roof in the Jiaxian area, with a mean sealing index of 3.12, surpasses the floor's sealing capacity by 13.87%, which averages 2.74. The sealing of the coal seam roof has a more positive impact on the enrichment of coalbed methane (CBM). In addition, the conditions for preserving gas would be boosted as coal seam thickness increased, leading to enhanced gas content in coal seams. The CH4 content increases by an average of ~2.38 m3/t as coal seam thickness increases with the interval of 1 m. The increasing burial depth represents the incremental maturity of organic matter and the gas generation ability in coal seams, which contributes to improving the gas content in coal seams. There is a positive correlation between the degree of coal fragmentation and the gas content of the coal seam to a certain extent. These findings provide valuable insights for targeted drilling strategies and enhancing natural gas production capacity in the Jiaxian area of the Ordos Basin. [ABSTRACT FROM AUTHOR]

Electromagnetic exploration, characterized by its low cost, wide applicability, and high operational efficiency, finds extensive applications in fields such as oil and gas exploration, mineral prospecting, and engineering geology. Traditional controlled-source electromagnetic detection methods are typically confined to operating frequencies below 250 kHz, resulting in insufficient detection accuracy for applications such as shallow and intermediate-depth exploration, thereby constraining their performance in high-resolution imaging. To address these challenges, we propose a controlled-source ultra-audio frequency electromagnetic receive system based on the Internet of Things (IoT). We investigate cascaded digital filtering and sampling techniques to extend the receiver's sampling rate range, thereby elevating the operating frequency of controlled-source electromagnetic acquisition from the conventional maximum of 250 kHz to 1 MHz. The receiver achieves a sampling rate of up to 2.5 MHz, comprising three magnetic field measurement channels and two electric field measurement channels. The instrument is compact, lightweight, capable of real-time data storage locally, and real-time data transmission to an upper computer. Additionally, IoT technology is introduced, leading to the design of a cloud-based real-time remote control and data acquisition scheme. Experimental results demonstrate the stability of the instrument, meeting the requirements of field exploration. [ABSTRACT FROM AUTHOR]

With the advancement of new food processing technology, triploid technology has emerged as a viable option to enhance plant yield and improve crop stress resistance. However, like many emerging technologies, food produced using triploid technology has sparked controversy regarding its safety since its inception. Particularly, consumers generally have a limited understanding of new technologies employed in food production, leading to concerns about potential risks and uncertainties associated with these technologies. Such concerns can significantly impact consumers' acceptance and purchasing intentions toward foods modified using new technologies. This study collected 375 questionnaires from both online and offline sources and conducted a detailed analysis of consumers' demographic variables, fear degree regarding triploid food, social trust, and concerns about food safety. SPSS and AMOS software were utilized for reliability and validity analysis, variance analysis, multiple comparisons, and confirmatory factor analysis. A structural equation model was developed to comprehensively examine consumers' risk perception of triploid food and its influencing factors. The results indicate that consumers' risk perception of triploid food is influenced by various factors. Notably, significant differences were found in consumers' risk perception of triploid food based on age, educational background, residency, and employment status. Additionally, this study identified a negative correlation between consumers' risk perception of triploid food and their levels of fear and social trust. Conversely, a positive correlation was observed between risk perception and the degree of attention given to food safety. [ABSTRACT FROM AUTHOR]

The research on the deep coalbed methane (CBM) in the Ordos Basin is mostly concentrated on the eastern margin of the basin. The geological resources of the Benxi Formation in the Yulin area, located in the central-eastern part, cover 15,000 × 108 m3, indicating enormous resource potential. However, the characteristics of the reservoir distribution and the favorable areas are not yet clear. This research comprehensively performed data logging, coal rock experiments, and core observations to identify the geological characteristics of the #8 coal seam, using a multi-level fuzzy mathematics method to evaluate the favorable area. The results indicate the following: (1) The thickness of the #8 coal in the Yulin Block ranges from 2.20 m to 11.37 m, with depths of between 2285.72 m and 3282.98 m, and it is mainly underlain by mudstone; the gas content ranges from 9.74 m3/t to 23.38 m3/t, showing a northwest–low and southeast–high trend. The overall area contains low-permeability reservoirs, with a prevalence of primary structural coal. (2) A multi-level evaluation system for deep CBM was established, dividing the Yulin Block into three types of favorable areas. This block features a wide range of Type I favorable areas, concentrated in the central-eastern, northern, and southwestern parts; Type II areas are closely distributed around the edges of Type I areas. The subsequent development process should prioritize the central-eastern part of the study area. The evaluation system established provides a reference for selecting favorable areas for deep CBM and offers theoretical guidance for targeted exploration and development in the Yulin area. [ABSTRACT FROM AUTHOR]

We designed a low-cost expandable current profiler (XCP) including software and hardware. An XCP is an observation instrument that rapidly measures currents based on the principle that currents cut the geomagnetic field to induce electric fields. The cost of an XCP must be reduced because it is a single-use device. The digitization of the previously developed XCP is carried out underwater, which requires the probe to contain not only analogue circuits for acquiring signals but also digital circuits and digital chips, which are relatively expensive. In this study, an XCP was developed that adopts signal modulation and demodulation to transmit analogue signals on an enamelled wire, and the signal digitization occurs above the surface of the water. The cost of the instrument was effectively reduced by half while maintaining its ability to measure parameters such as sea current and temperature in real time. After comparison with data processed from laboratory tests, the acquisition circuit showed an accuracy within 0.1 % and the XCP analogue circuit developed for the overall system was stable and reliable. The system exhibited an acquisition accuracy higher than 50 nV for 16 Hz, and the quality of the acquired signal satisfied the requirements for an XCP instrument. [ABSTRACT FROM AUTHOR]

We present here the influence of different surface terminations on the electronic, optical, and photocatalytic properties of trans and cis BaTaO2N using density functional theory calculations. For each surface, we consider two complementary terminations exposed with Ba and Ta atoms, respectively. The calculated surface energies suggest that (001) and (100) are more stable than other low-index surfaces. Work functions are distinct for various surface terminations, which can be attributed to the atomic displacements in different directions and degrees after relaxation. We propose that the transferring direction of the photogenerated carriers in BaTaO2N-based heterostructures could be controlled by obtaining the preferred surface termination. The simulated absorption spectra suggest that both trans and cis BaTaO2N exhibit optical anisotropy, which could result from the difference in relaxed crystal parameters along different directions. Dissociative water adsorption on both the (001) and (100) terminations is thermodynamically favorable. The hydrogen evolution reaction (HER) is easier to occur on the terminations exposed with Ta, O, and N simultaneously. The computed overpotentials of oxygen evolution reaction (OER) for trans-(001)-BaO, cis-(001)-TaON, cis-(001)-BaO, and cis-(100)-Ta2O3N are in good agreement with the experimental results. These findings provide important insights into the rational design of (001)- and (100)-oriented BaTaO2N samples for enhanced photocatalytic activity. [ABSTRACT FROM AUTHOR]

Electrical resistivity tomography (ERT) is an important method for exploring oil and gas formations, mineral deposits, and groundwater resources. However, most ERT instruments have limitations such as complicated human–computer interaction, few measurement parameters, difficulties in remote monitoring, and lack of four-dimensional (4D) exploration functions. To overcome these limitations, in this study we proposed and developed software for a remote control 4D ERT system based on a cloud platform and Internet of Things (IoT) technology. Specifically, acquisition device control, channel and control, acquisition control, and remote monitoring systems were designed, with various modules being debugged and optimized multiple times. The system is equipped with a 4G module, through which the collected data are transmitted to the cloud platform to realize real-time, stable, and long-distance data acquisition and transmission. Furthermore, the system realizes remote monitoring, real-time measurement, and other functions via the cloud and IoT technology, thereby providing strong technical support for achieving 4D exploration. The developed system was empirically evaluated by applying it to explore the Gequ Landslide area in Jainca County, Qinghai Province, China. The exploration results indicate that the system software has stable functions and high intelligence; thus it satisfies the requirements for field exploration. [ABSTRACT FROM AUTHOR]

ABSTRACT In this study, a polar seismic acquisition station based on the FPGA + ARM architecture was successfully developed. This system can achieve real‐time multifunctional acquisition and transmission of seismic signals and environmental information in the extreme low‐temperature environment of Antarctica at −40°C. The system adopts a modular design, with high‐precision data acquisition encoded by the main controller and uploaded to the host computer in real‐time. Integrated display controls enable real‐time data display and acquisition station location mapping for user interaction. We propose improving data transmission in traditional seismic acquisition stations by adopting a distributed computing model with data segment return. Integrating the first arrival picking algorithm as an IP core will reduce computational demands on the data processing center. This acquisition system features high precision (24‐bit), a wide dynamic range (> 130dB), low noise (0.5 μ$$ \upmu $$V rms@40dB), and high‐precision timing control (200 ns). It supports real‐time wireless data transmission over 120 channels up to 1 km. The system also implements a self‐storage plus wired and wireless networking solution, allowing flexible networking based on actual needs. Test results indicate that the ice sheet thickness at the acquisition site is approximately 526.49 m, validating the experimental design's effectiveness and providing technical support for subsequent drilling and seismic exploration. [ABSTRACT FROM AUTHOR]

Gas chromatography coupled with tandem mass spectrometry (GC-MS-MS) operated in MRM mode is a powerful technology for multi-residue analysis in complex food matrices. Good GC separation combined with MS-MS selectivity [...]